1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/sched.h>
7 #include <linux/sched/mm.h>
8 #include <linux/slab.h>
9 #include <linux/ratelimit.h>
10 #include <linux/kthread.h>
11 #include <linux/semaphore.h>
12 #include <linux/uuid.h>
13 #include <linux/list_sort.h>
14 #include <linux/namei.h>
15 #include "misc.h"
16 #include "disk-io.h"
17 #include "extent-tree.h"
18 #include "transaction.h"
19 #include "volumes.h"
20 #include "raid56.h"
21 #include "rcu-string.h"
22 #include "dev-replace.h"
23 #include "sysfs.h"
24 #include "tree-checker.h"
25 #include "space-info.h"
26 #include "block-group.h"
27 #include "discard.h"
28 #include "zoned.h"
29 #include "fs.h"
30 #include "accessors.h"
31 #include "uuid-tree.h"
32 #include "ioctl.h"
33 #include "relocation.h"
34 #include "scrub.h"
35 #include "super.h"
36 #include "raid-stripe-tree.h"
37
38 #define BTRFS_BLOCK_GROUP_STRIPE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \
39 BTRFS_BLOCK_GROUP_RAID10 | \
40 BTRFS_BLOCK_GROUP_RAID56_MASK)
41
42 struct btrfs_io_geometry {
43 u32 stripe_index;
44 u32 stripe_nr;
45 int mirror_num;
46 int num_stripes;
47 u64 stripe_offset;
48 u64 raid56_full_stripe_start;
49 int max_errors;
50 enum btrfs_map_op op;
51 bool use_rst;
52 };
53
54 const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
55 [BTRFS_RAID_RAID10] = {
56 .sub_stripes = 2,
57 .dev_stripes = 1,
58 .devs_max = 0, /* 0 == as many as possible */
59 .devs_min = 2,
60 .tolerated_failures = 1,
61 .devs_increment = 2,
62 .ncopies = 2,
63 .nparity = 0,
64 .raid_name = "raid10",
65 .bg_flag = BTRFS_BLOCK_GROUP_RAID10,
66 .mindev_error = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET,
67 },
68 [BTRFS_RAID_RAID1] = {
69 .sub_stripes = 1,
70 .dev_stripes = 1,
71 .devs_max = 2,
72 .devs_min = 2,
73 .tolerated_failures = 1,
74 .devs_increment = 2,
75 .ncopies = 2,
76 .nparity = 0,
77 .raid_name = "raid1",
78 .bg_flag = BTRFS_BLOCK_GROUP_RAID1,
79 .mindev_error = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET,
80 },
81 [BTRFS_RAID_RAID1C3] = {
82 .sub_stripes = 1,
83 .dev_stripes = 1,
84 .devs_max = 3,
85 .devs_min = 3,
86 .tolerated_failures = 2,
87 .devs_increment = 3,
88 .ncopies = 3,
89 .nparity = 0,
90 .raid_name = "raid1c3",
91 .bg_flag = BTRFS_BLOCK_GROUP_RAID1C3,
92 .mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET,
93 },
94 [BTRFS_RAID_RAID1C4] = {
95 .sub_stripes = 1,
96 .dev_stripes = 1,
97 .devs_max = 4,
98 .devs_min = 4,
99 .tolerated_failures = 3,
100 .devs_increment = 4,
101 .ncopies = 4,
102 .nparity = 0,
103 .raid_name = "raid1c4",
104 .bg_flag = BTRFS_BLOCK_GROUP_RAID1C4,
105 .mindev_error = BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET,
106 },
107 [BTRFS_RAID_DUP] = {
108 .sub_stripes = 1,
109 .dev_stripes = 2,
110 .devs_max = 1,
111 .devs_min = 1,
112 .tolerated_failures = 0,
113 .devs_increment = 1,
114 .ncopies = 2,
115 .nparity = 0,
116 .raid_name = "dup",
117 .bg_flag = BTRFS_BLOCK_GROUP_DUP,
118 .mindev_error = 0,
119 },
120 [BTRFS_RAID_RAID0] = {
121 .sub_stripes = 1,
122 .dev_stripes = 1,
123 .devs_max = 0,
124 .devs_min = 1,
125 .tolerated_failures = 0,
126 .devs_increment = 1,
127 .ncopies = 1,
128 .nparity = 0,
129 .raid_name = "raid0",
130 .bg_flag = BTRFS_BLOCK_GROUP_RAID0,
131 .mindev_error = 0,
132 },
133 [BTRFS_RAID_SINGLE] = {
134 .sub_stripes = 1,
135 .dev_stripes = 1,
136 .devs_max = 1,
137 .devs_min = 1,
138 .tolerated_failures = 0,
139 .devs_increment = 1,
140 .ncopies = 1,
141 .nparity = 0,
142 .raid_name = "single",
143 .bg_flag = 0,
144 .mindev_error = 0,
145 },
146 [BTRFS_RAID_RAID5] = {
147 .sub_stripes = 1,
148 .dev_stripes = 1,
149 .devs_max = 0,
150 .devs_min = 2,
151 .tolerated_failures = 1,
152 .devs_increment = 1,
153 .ncopies = 1,
154 .nparity = 1,
155 .raid_name = "raid5",
156 .bg_flag = BTRFS_BLOCK_GROUP_RAID5,
157 .mindev_error = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET,
158 },
159 [BTRFS_RAID_RAID6] = {
160 .sub_stripes = 1,
161 .dev_stripes = 1,
162 .devs_max = 0,
163 .devs_min = 3,
164 .tolerated_failures = 2,
165 .devs_increment = 1,
166 .ncopies = 1,
167 .nparity = 2,
168 .raid_name = "raid6",
169 .bg_flag = BTRFS_BLOCK_GROUP_RAID6,
170 .mindev_error = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET,
171 },
172 };
173
174 /*
175 * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
176 * can be used as index to access btrfs_raid_array[].
177 */
btrfs_bg_flags_to_raid_index(u64 flags)178 enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags)
179 {
180 const u64 profile = (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK);
181
182 if (!profile)
183 return BTRFS_RAID_SINGLE;
184
185 return BTRFS_BG_FLAG_TO_INDEX(profile);
186 }
187
btrfs_bg_type_to_raid_name(u64 flags)188 const char *btrfs_bg_type_to_raid_name(u64 flags)
189 {
190 const int index = btrfs_bg_flags_to_raid_index(flags);
191
192 if (index >= BTRFS_NR_RAID_TYPES)
193 return NULL;
194
195 return btrfs_raid_array[index].raid_name;
196 }
197
btrfs_nr_parity_stripes(u64 type)198 int btrfs_nr_parity_stripes(u64 type)
199 {
200 enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(type);
201
202 return btrfs_raid_array[index].nparity;
203 }
204
205 /*
206 * Fill @buf with textual description of @bg_flags, no more than @size_buf
207 * bytes including terminating null byte.
208 */
btrfs_describe_block_groups(u64 bg_flags,char * buf,u32 size_buf)209 void btrfs_describe_block_groups(u64 bg_flags, char *buf, u32 size_buf)
210 {
211 int i;
212 int ret;
213 char *bp = buf;
214 u64 flags = bg_flags;
215 u32 size_bp = size_buf;
216
217 if (!flags) {
218 strcpy(bp, "NONE");
219 return;
220 }
221
222 #define DESCRIBE_FLAG(flag, desc) \
223 do { \
224 if (flags & (flag)) { \
225 ret = snprintf(bp, size_bp, "%s|", (desc)); \
226 if (ret < 0 || ret >= size_bp) \
227 goto out_overflow; \
228 size_bp -= ret; \
229 bp += ret; \
230 flags &= ~(flag); \
231 } \
232 } while (0)
233
234 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_DATA, "data");
235 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_SYSTEM, "system");
236 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_METADATA, "metadata");
237
238 DESCRIBE_FLAG(BTRFS_AVAIL_ALLOC_BIT_SINGLE, "single");
239 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
240 DESCRIBE_FLAG(btrfs_raid_array[i].bg_flag,
241 btrfs_raid_array[i].raid_name);
242 #undef DESCRIBE_FLAG
243
244 if (flags) {
245 ret = snprintf(bp, size_bp, "0x%llx|", flags);
246 size_bp -= ret;
247 }
248
249 if (size_bp < size_buf)
250 buf[size_buf - size_bp - 1] = '\0'; /* remove last | */
251
252 /*
253 * The text is trimmed, it's up to the caller to provide sufficiently
254 * large buffer
255 */
256 out_overflow:;
257 }
258
259 static int init_first_rw_device(struct btrfs_trans_handle *trans);
260 static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info);
261 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
262
263 /*
264 * Device locking
265 * ==============
266 *
267 * There are several mutexes that protect manipulation of devices and low-level
268 * structures like chunks but not block groups, extents or files
269 *
270 * uuid_mutex (global lock)
271 * ------------------------
272 * protects the fs_uuids list that tracks all per-fs fs_devices, resulting from
273 * the SCAN_DEV ioctl registration or from mount either implicitly (the first
274 * device) or requested by the device= mount option
275 *
276 * the mutex can be very coarse and can cover long-running operations
277 *
278 * protects: updates to fs_devices counters like missing devices, rw devices,
279 * seeding, structure cloning, opening/closing devices at mount/umount time
280 *
281 * global::fs_devs - add, remove, updates to the global list
282 *
283 * does not protect: manipulation of the fs_devices::devices list in general
284 * but in mount context it could be used to exclude list modifications by eg.
285 * scan ioctl
286 *
287 * btrfs_device::name - renames (write side), read is RCU
288 *
289 * fs_devices::device_list_mutex (per-fs, with RCU)
290 * ------------------------------------------------
291 * protects updates to fs_devices::devices, ie. adding and deleting
292 *
293 * simple list traversal with read-only actions can be done with RCU protection
294 *
295 * may be used to exclude some operations from running concurrently without any
296 * modifications to the list (see write_all_supers)
297 *
298 * Is not required at mount and close times, because our device list is
299 * protected by the uuid_mutex at that point.
300 *
301 * balance_mutex
302 * -------------
303 * protects balance structures (status, state) and context accessed from
304 * several places (internally, ioctl)
305 *
306 * chunk_mutex
307 * -----------
308 * protects chunks, adding or removing during allocation, trim or when a new
309 * device is added/removed. Additionally it also protects post_commit_list of
310 * individual devices, since they can be added to the transaction's
311 * post_commit_list only with chunk_mutex held.
312 *
313 * cleaner_mutex
314 * -------------
315 * a big lock that is held by the cleaner thread and prevents running subvolume
316 * cleaning together with relocation or delayed iputs
317 *
318 *
319 * Lock nesting
320 * ============
321 *
322 * uuid_mutex
323 * device_list_mutex
324 * chunk_mutex
325 * balance_mutex
326 *
327 *
328 * Exclusive operations
329 * ====================
330 *
331 * Maintains the exclusivity of the following operations that apply to the
332 * whole filesystem and cannot run in parallel.
333 *
334 * - Balance (*)
335 * - Device add
336 * - Device remove
337 * - Device replace (*)
338 * - Resize
339 *
340 * The device operations (as above) can be in one of the following states:
341 *
342 * - Running state
343 * - Paused state
344 * - Completed state
345 *
346 * Only device operations marked with (*) can go into the Paused state for the
347 * following reasons:
348 *
349 * - ioctl (only Balance can be Paused through ioctl)
350 * - filesystem remounted as read-only
351 * - filesystem unmounted and mounted as read-only
352 * - system power-cycle and filesystem mounted as read-only
353 * - filesystem or device errors leading to forced read-only
354 *
355 * The status of exclusive operation is set and cleared atomically.
356 * During the course of Paused state, fs_info::exclusive_operation remains set.
357 * A device operation in Paused or Running state can be canceled or resumed
358 * either by ioctl (Balance only) or when remounted as read-write.
359 * The exclusive status is cleared when the device operation is canceled or
360 * completed.
361 */
362
363 DEFINE_MUTEX(uuid_mutex);
364 static LIST_HEAD(fs_uuids);
btrfs_get_fs_uuids(void)365 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void)
366 {
367 return &fs_uuids;
368 }
369
370 /*
371 * Allocate new btrfs_fs_devices structure identified by a fsid.
372 *
373 * @fsid: if not NULL, copy the UUID to fs_devices::fsid and to
374 * fs_devices::metadata_fsid
375 *
376 * Return a pointer to a new struct btrfs_fs_devices on success, or ERR_PTR().
377 * The returned struct is not linked onto any lists and can be destroyed with
378 * kfree() right away.
379 */
alloc_fs_devices(const u8 * fsid)380 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
381 {
382 struct btrfs_fs_devices *fs_devs;
383
384 fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL);
385 if (!fs_devs)
386 return ERR_PTR(-ENOMEM);
387
388 mutex_init(&fs_devs->device_list_mutex);
389
390 INIT_LIST_HEAD(&fs_devs->devices);
391 INIT_LIST_HEAD(&fs_devs->alloc_list);
392 INIT_LIST_HEAD(&fs_devs->fs_list);
393 INIT_LIST_HEAD(&fs_devs->seed_list);
394
395 if (fsid) {
396 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
397 memcpy(fs_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE);
398 }
399
400 return fs_devs;
401 }
402
btrfs_free_device(struct btrfs_device * device)403 static void btrfs_free_device(struct btrfs_device *device)
404 {
405 WARN_ON(!list_empty(&device->post_commit_list));
406 rcu_string_free(device->name);
407 extent_io_tree_release(&device->alloc_state);
408 btrfs_destroy_dev_zone_info(device);
409 kfree(device);
410 }
411
free_fs_devices(struct btrfs_fs_devices * fs_devices)412 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
413 {
414 struct btrfs_device *device;
415
416 WARN_ON(fs_devices->opened);
417 while (!list_empty(&fs_devices->devices)) {
418 device = list_entry(fs_devices->devices.next,
419 struct btrfs_device, dev_list);
420 list_del(&device->dev_list);
421 btrfs_free_device(device);
422 }
423 kfree(fs_devices);
424 }
425
btrfs_cleanup_fs_uuids(void)426 void __exit btrfs_cleanup_fs_uuids(void)
427 {
428 struct btrfs_fs_devices *fs_devices;
429
430 while (!list_empty(&fs_uuids)) {
431 fs_devices = list_entry(fs_uuids.next,
432 struct btrfs_fs_devices, fs_list);
433 list_del(&fs_devices->fs_list);
434 free_fs_devices(fs_devices);
435 }
436 }
437
match_fsid_fs_devices(const struct btrfs_fs_devices * fs_devices,const u8 * fsid,const u8 * metadata_fsid)438 static bool match_fsid_fs_devices(const struct btrfs_fs_devices *fs_devices,
439 const u8 *fsid, const u8 *metadata_fsid)
440 {
441 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) != 0)
442 return false;
443
444 if (!metadata_fsid)
445 return true;
446
447 if (memcmp(metadata_fsid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE) != 0)
448 return false;
449
450 return true;
451 }
452
find_fsid(const u8 * fsid,const u8 * metadata_fsid)453 static noinline struct btrfs_fs_devices *find_fsid(
454 const u8 *fsid, const u8 *metadata_fsid)
455 {
456 struct btrfs_fs_devices *fs_devices;
457
458 ASSERT(fsid);
459
460 /* Handle non-split brain cases */
461 list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
462 if (match_fsid_fs_devices(fs_devices, fsid, metadata_fsid))
463 return fs_devices;
464 }
465 return NULL;
466 }
467
468 static int
btrfs_get_bdev_and_sb(const char * device_path,blk_mode_t flags,void * holder,int flush,struct file ** bdev_file,struct btrfs_super_block ** disk_super)469 btrfs_get_bdev_and_sb(const char *device_path, blk_mode_t flags, void *holder,
470 int flush, struct file **bdev_file,
471 struct btrfs_super_block **disk_super)
472 {
473 struct block_device *bdev;
474 int ret;
475
476 *bdev_file = bdev_file_open_by_path(device_path, flags, holder, NULL);
477
478 if (IS_ERR(*bdev_file)) {
479 ret = PTR_ERR(*bdev_file);
480 btrfs_err(NULL, "failed to open device for path %s with flags 0x%x: %d",
481 device_path, flags, ret);
482 goto error;
483 }
484 bdev = file_bdev(*bdev_file);
485
486 if (flush)
487 sync_blockdev(bdev);
488 if (holder) {
489 ret = set_blocksize(*bdev_file, BTRFS_BDEV_BLOCKSIZE);
490 if (ret) {
491 fput(*bdev_file);
492 goto error;
493 }
494 }
495 invalidate_bdev(bdev);
496 *disk_super = btrfs_read_dev_super(bdev);
497 if (IS_ERR(*disk_super)) {
498 ret = PTR_ERR(*disk_super);
499 fput(*bdev_file);
500 goto error;
501 }
502
503 return 0;
504
505 error:
506 *disk_super = NULL;
507 *bdev_file = NULL;
508 return ret;
509 }
510
511 /*
512 * Search and remove all stale devices (which are not mounted). When both
513 * inputs are NULL, it will search and release all stale devices.
514 *
515 * @devt: Optional. When provided will it release all unmounted devices
516 * matching this devt only.
517 * @skip_device: Optional. Will skip this device when searching for the stale
518 * devices.
519 *
520 * Return: 0 for success or if @devt is 0.
521 * -EBUSY if @devt is a mounted device.
522 * -ENOENT if @devt does not match any device in the list.
523 */
btrfs_free_stale_devices(dev_t devt,struct btrfs_device * skip_device)524 static int btrfs_free_stale_devices(dev_t devt, struct btrfs_device *skip_device)
525 {
526 struct btrfs_fs_devices *fs_devices, *tmp_fs_devices;
527 struct btrfs_device *device, *tmp_device;
528 int ret;
529 bool freed = false;
530
531 lockdep_assert_held(&uuid_mutex);
532
533 /* Return good status if there is no instance of devt. */
534 ret = 0;
535 list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) {
536
537 mutex_lock(&fs_devices->device_list_mutex);
538 list_for_each_entry_safe(device, tmp_device,
539 &fs_devices->devices, dev_list) {
540 if (skip_device && skip_device == device)
541 continue;
542 if (devt && devt != device->devt)
543 continue;
544 if (fs_devices->opened) {
545 if (devt)
546 ret = -EBUSY;
547 break;
548 }
549
550 /* delete the stale device */
551 fs_devices->num_devices--;
552 list_del(&device->dev_list);
553 btrfs_free_device(device);
554
555 freed = true;
556 }
557 mutex_unlock(&fs_devices->device_list_mutex);
558
559 if (fs_devices->num_devices == 0) {
560 btrfs_sysfs_remove_fsid(fs_devices);
561 list_del(&fs_devices->fs_list);
562 free_fs_devices(fs_devices);
563 }
564 }
565
566 /* If there is at least one freed device return 0. */
567 if (freed)
568 return 0;
569
570 return ret;
571 }
572
find_fsid_by_device(struct btrfs_super_block * disk_super,dev_t devt,bool * same_fsid_diff_dev)573 static struct btrfs_fs_devices *find_fsid_by_device(
574 struct btrfs_super_block *disk_super,
575 dev_t devt, bool *same_fsid_diff_dev)
576 {
577 struct btrfs_fs_devices *fsid_fs_devices;
578 struct btrfs_fs_devices *devt_fs_devices;
579 const bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
580 BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
581 bool found_by_devt = false;
582
583 /* Find the fs_device by the usual method, if found use it. */
584 fsid_fs_devices = find_fsid(disk_super->fsid,
585 has_metadata_uuid ? disk_super->metadata_uuid : NULL);
586
587 /* The temp_fsid feature is supported only with single device filesystem. */
588 if (btrfs_super_num_devices(disk_super) != 1)
589 return fsid_fs_devices;
590
591 /*
592 * A seed device is an integral component of the sprout device, which
593 * functions as a multi-device filesystem. So, temp-fsid feature is
594 * not supported.
595 */
596 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING)
597 return fsid_fs_devices;
598
599 /* Try to find a fs_devices by matching devt. */
600 list_for_each_entry(devt_fs_devices, &fs_uuids, fs_list) {
601 struct btrfs_device *device;
602
603 list_for_each_entry(device, &devt_fs_devices->devices, dev_list) {
604 if (device->devt == devt) {
605 found_by_devt = true;
606 break;
607 }
608 }
609 if (found_by_devt)
610 break;
611 }
612
613 if (found_by_devt) {
614 /* Existing device. */
615 if (fsid_fs_devices == NULL) {
616 if (devt_fs_devices->opened == 0) {
617 /* Stale device. */
618 return NULL;
619 } else {
620 /* temp_fsid is mounting a subvol. */
621 return devt_fs_devices;
622 }
623 } else {
624 /* Regular or temp_fsid device mounting a subvol. */
625 return devt_fs_devices;
626 }
627 } else {
628 /* New device. */
629 if (fsid_fs_devices == NULL) {
630 return NULL;
631 } else {
632 /* sb::fsid is already used create a new temp_fsid. */
633 *same_fsid_diff_dev = true;
634 return NULL;
635 }
636 }
637
638 /* Not reached. */
639 }
640
641 /*
642 * This is only used on mount, and we are protected from competing things
643 * messing with our fs_devices by the uuid_mutex, thus we do not need the
644 * fs_devices->device_list_mutex here.
645 */
btrfs_open_one_device(struct btrfs_fs_devices * fs_devices,struct btrfs_device * device,blk_mode_t flags,void * holder)646 static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
647 struct btrfs_device *device, blk_mode_t flags,
648 void *holder)
649 {
650 struct file *bdev_file;
651 struct btrfs_super_block *disk_super;
652 u64 devid;
653 int ret;
654
655 if (device->bdev)
656 return -EINVAL;
657 if (!device->name)
658 return -EINVAL;
659
660 ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
661 &bdev_file, &disk_super);
662 if (ret)
663 return ret;
664
665 devid = btrfs_stack_device_id(&disk_super->dev_item);
666 if (devid != device->devid)
667 goto error_free_page;
668
669 if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE))
670 goto error_free_page;
671
672 device->generation = btrfs_super_generation(disk_super);
673
674 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
675 if (btrfs_super_incompat_flags(disk_super) &
676 BTRFS_FEATURE_INCOMPAT_METADATA_UUID) {
677 pr_err(
678 "BTRFS: Invalid seeding and uuid-changed device detected\n");
679 goto error_free_page;
680 }
681
682 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
683 fs_devices->seeding = true;
684 } else {
685 if (bdev_read_only(file_bdev(bdev_file)))
686 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
687 else
688 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
689 }
690
691 if (!bdev_nonrot(file_bdev(bdev_file)))
692 fs_devices->rotating = true;
693
694 if (bdev_max_discard_sectors(file_bdev(bdev_file)))
695 fs_devices->discardable = true;
696
697 device->bdev_file = bdev_file;
698 device->bdev = file_bdev(bdev_file);
699 clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
700
701 if (device->devt != device->bdev->bd_dev) {
702 btrfs_warn(NULL,
703 "device %s maj:min changed from %d:%d to %d:%d",
704 device->name->str, MAJOR(device->devt),
705 MINOR(device->devt), MAJOR(device->bdev->bd_dev),
706 MINOR(device->bdev->bd_dev));
707
708 device->devt = device->bdev->bd_dev;
709 }
710
711 fs_devices->open_devices++;
712 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
713 device->devid != BTRFS_DEV_REPLACE_DEVID) {
714 fs_devices->rw_devices++;
715 list_add_tail(&device->dev_alloc_list, &fs_devices->alloc_list);
716 }
717 btrfs_release_disk_super(disk_super);
718
719 return 0;
720
721 error_free_page:
722 btrfs_release_disk_super(disk_super);
723 fput(bdev_file);
724
725 return -EINVAL;
726 }
727
btrfs_sb_fsid_ptr(const struct btrfs_super_block * sb)728 const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb)
729 {
730 bool has_metadata_uuid = (btrfs_super_incompat_flags(sb) &
731 BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
732
733 return has_metadata_uuid ? sb->metadata_uuid : sb->fsid;
734 }
735
736 /*
737 * We can have very weird soft links passed in.
738 * One example is "/proc/self/fd/<fd>", which can be a soft link to
739 * a block device.
740 *
741 * But it's never a good idea to use those weird names.
742 * Here we check if the path (not following symlinks) is a good one inside
743 * "/dev/".
744 */
is_good_dev_path(const char * dev_path)745 static bool is_good_dev_path(const char *dev_path)
746 {
747 struct path path = { .mnt = NULL, .dentry = NULL };
748 char *path_buf = NULL;
749 char *resolved_path;
750 bool is_good = false;
751 int ret;
752
753 if (!dev_path)
754 goto out;
755
756 path_buf = kmalloc(PATH_MAX, GFP_KERNEL);
757 if (!path_buf)
758 goto out;
759
760 /*
761 * Do not follow soft link, just check if the original path is inside
762 * "/dev/".
763 */
764 ret = kern_path(dev_path, 0, &path);
765 if (ret)
766 goto out;
767 resolved_path = d_path(&path, path_buf, PATH_MAX);
768 if (IS_ERR(resolved_path))
769 goto out;
770 if (strncmp(resolved_path, "/dev/", strlen("/dev/")))
771 goto out;
772 is_good = true;
773 out:
774 kfree(path_buf);
775 path_put(&path);
776 return is_good;
777 }
778
get_canonical_dev_path(const char * dev_path,char * canonical)779 static int get_canonical_dev_path(const char *dev_path, char *canonical)
780 {
781 struct path path = { .mnt = NULL, .dentry = NULL };
782 char *path_buf = NULL;
783 char *resolved_path;
784 int ret;
785
786 if (!dev_path) {
787 ret = -EINVAL;
788 goto out;
789 }
790
791 path_buf = kmalloc(PATH_MAX, GFP_KERNEL);
792 if (!path_buf) {
793 ret = -ENOMEM;
794 goto out;
795 }
796
797 ret = kern_path(dev_path, LOOKUP_FOLLOW, &path);
798 if (ret)
799 goto out;
800 resolved_path = d_path(&path, path_buf, PATH_MAX);
801 if (IS_ERR(resolved_path)) {
802 ret = PTR_ERR(resolved_path);
803 goto out;
804 }
805 ret = strscpy(canonical, resolved_path, PATH_MAX);
806 out:
807 kfree(path_buf);
808 path_put(&path);
809 return ret;
810 }
811
is_same_device(struct btrfs_device * device,const char * new_path)812 static bool is_same_device(struct btrfs_device *device, const char *new_path)
813 {
814 struct path old = { .mnt = NULL, .dentry = NULL };
815 struct path new = { .mnt = NULL, .dentry = NULL };
816 char *old_path = NULL;
817 bool is_same = false;
818 int ret;
819
820 if (!device->name)
821 goto out;
822
823 old_path = kzalloc(PATH_MAX, GFP_NOFS);
824 if (!old_path)
825 goto out;
826
827 rcu_read_lock();
828 ret = strscpy(old_path, rcu_str_deref(device->name), PATH_MAX);
829 rcu_read_unlock();
830 if (ret < 0)
831 goto out;
832
833 ret = kern_path(old_path, LOOKUP_FOLLOW, &old);
834 if (ret)
835 goto out;
836 ret = kern_path(new_path, LOOKUP_FOLLOW, &new);
837 if (ret)
838 goto out;
839 if (path_equal(&old, &new))
840 is_same = true;
841 out:
842 kfree(old_path);
843 path_put(&old);
844 path_put(&new);
845 return is_same;
846 }
847
848 /*
849 * Add new device to list of registered devices
850 *
851 * Returns:
852 * device pointer which was just added or updated when successful
853 * error pointer when failed
854 */
device_list_add(const char * path,struct btrfs_super_block * disk_super,bool * new_device_added)855 static noinline struct btrfs_device *device_list_add(const char *path,
856 struct btrfs_super_block *disk_super,
857 bool *new_device_added)
858 {
859 struct btrfs_device *device;
860 struct btrfs_fs_devices *fs_devices = NULL;
861 struct rcu_string *name;
862 u64 found_transid = btrfs_super_generation(disk_super);
863 u64 devid = btrfs_stack_device_id(&disk_super->dev_item);
864 dev_t path_devt;
865 int error;
866 bool same_fsid_diff_dev = false;
867 bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
868 BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
869
870 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
871 btrfs_err(NULL,
872 "device %s has incomplete metadata_uuid change, please use btrfstune to complete",
873 path);
874 return ERR_PTR(-EAGAIN);
875 }
876
877 error = lookup_bdev(path, &path_devt);
878 if (error) {
879 btrfs_err(NULL, "failed to lookup block device for path %s: %d",
880 path, error);
881 return ERR_PTR(error);
882 }
883
884 fs_devices = find_fsid_by_device(disk_super, path_devt, &same_fsid_diff_dev);
885
886 if (!fs_devices) {
887 fs_devices = alloc_fs_devices(disk_super->fsid);
888 if (IS_ERR(fs_devices))
889 return ERR_CAST(fs_devices);
890
891 if (has_metadata_uuid)
892 memcpy(fs_devices->metadata_uuid,
893 disk_super->metadata_uuid, BTRFS_FSID_SIZE);
894
895 if (same_fsid_diff_dev) {
896 generate_random_uuid(fs_devices->fsid);
897 fs_devices->temp_fsid = true;
898 pr_info("BTRFS: device %s (%d:%d) using temp-fsid %pU\n",
899 path, MAJOR(path_devt), MINOR(path_devt),
900 fs_devices->fsid);
901 }
902
903 mutex_lock(&fs_devices->device_list_mutex);
904 list_add(&fs_devices->fs_list, &fs_uuids);
905
906 device = NULL;
907 } else {
908 struct btrfs_dev_lookup_args args = {
909 .devid = devid,
910 .uuid = disk_super->dev_item.uuid,
911 };
912
913 mutex_lock(&fs_devices->device_list_mutex);
914 device = btrfs_find_device(fs_devices, &args);
915
916 if (found_transid > fs_devices->latest_generation) {
917 memcpy(fs_devices->fsid, disk_super->fsid,
918 BTRFS_FSID_SIZE);
919 memcpy(fs_devices->metadata_uuid,
920 btrfs_sb_fsid_ptr(disk_super), BTRFS_FSID_SIZE);
921 }
922 }
923
924 if (!device) {
925 unsigned int nofs_flag;
926
927 if (fs_devices->opened) {
928 btrfs_err(NULL,
929 "device %s (%d:%d) belongs to fsid %pU, and the fs is already mounted, scanned by %s (%d)",
930 path, MAJOR(path_devt), MINOR(path_devt),
931 fs_devices->fsid, current->comm,
932 task_pid_nr(current));
933 mutex_unlock(&fs_devices->device_list_mutex);
934 return ERR_PTR(-EBUSY);
935 }
936
937 nofs_flag = memalloc_nofs_save();
938 device = btrfs_alloc_device(NULL, &devid,
939 disk_super->dev_item.uuid, path);
940 memalloc_nofs_restore(nofs_flag);
941 if (IS_ERR(device)) {
942 mutex_unlock(&fs_devices->device_list_mutex);
943 /* we can safely leave the fs_devices entry around */
944 return device;
945 }
946
947 device->devt = path_devt;
948
949 list_add_rcu(&device->dev_list, &fs_devices->devices);
950 fs_devices->num_devices++;
951
952 device->fs_devices = fs_devices;
953 *new_device_added = true;
954
955 if (disk_super->label[0])
956 pr_info(
957 "BTRFS: device label %s devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n",
958 disk_super->label, devid, found_transid, path,
959 MAJOR(path_devt), MINOR(path_devt),
960 current->comm, task_pid_nr(current));
961 else
962 pr_info(
963 "BTRFS: device fsid %pU devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n",
964 disk_super->fsid, devid, found_transid, path,
965 MAJOR(path_devt), MINOR(path_devt),
966 current->comm, task_pid_nr(current));
967
968 } else if (!device->name || !is_same_device(device, path)) {
969 /*
970 * When FS is already mounted.
971 * 1. If you are here and if the device->name is NULL that
972 * means this device was missing at time of FS mount.
973 * 2. If you are here and if the device->name is different
974 * from 'path' that means either
975 * a. The same device disappeared and reappeared with
976 * different name. or
977 * b. The missing-disk-which-was-replaced, has
978 * reappeared now.
979 *
980 * We must allow 1 and 2a above. But 2b would be a spurious
981 * and unintentional.
982 *
983 * Further in case of 1 and 2a above, the disk at 'path'
984 * would have missed some transaction when it was away and
985 * in case of 2a the stale bdev has to be updated as well.
986 * 2b must not be allowed at all time.
987 */
988
989 /*
990 * For now, we do allow update to btrfs_fs_device through the
991 * btrfs dev scan cli after FS has been mounted. We're still
992 * tracking a problem where systems fail mount by subvolume id
993 * when we reject replacement on a mounted FS.
994 */
995 if (!fs_devices->opened && found_transid < device->generation) {
996 /*
997 * That is if the FS is _not_ mounted and if you
998 * are here, that means there is more than one
999 * disk with same uuid and devid.We keep the one
1000 * with larger generation number or the last-in if
1001 * generation are equal.
1002 */
1003 mutex_unlock(&fs_devices->device_list_mutex);
1004 btrfs_err(NULL,
1005 "device %s already registered with a higher generation, found %llu expect %llu",
1006 path, found_transid, device->generation);
1007 return ERR_PTR(-EEXIST);
1008 }
1009
1010 /*
1011 * We are going to replace the device path for a given devid,
1012 * make sure it's the same device if the device is mounted
1013 *
1014 * NOTE: the device->fs_info may not be reliable here so pass
1015 * in a NULL to message helpers instead. This avoids a possible
1016 * use-after-free when the fs_info and fs_info->sb are already
1017 * torn down.
1018 */
1019 if (device->bdev) {
1020 if (device->devt != path_devt) {
1021 mutex_unlock(&fs_devices->device_list_mutex);
1022 btrfs_warn_in_rcu(NULL,
1023 "duplicate device %s devid %llu generation %llu scanned by %s (%d)",
1024 path, devid, found_transid,
1025 current->comm,
1026 task_pid_nr(current));
1027 return ERR_PTR(-EEXIST);
1028 }
1029 btrfs_info_in_rcu(NULL,
1030 "devid %llu device path %s changed to %s scanned by %s (%d)",
1031 devid, btrfs_dev_name(device),
1032 path, current->comm,
1033 task_pid_nr(current));
1034 }
1035
1036 name = rcu_string_strdup(path, GFP_NOFS);
1037 if (!name) {
1038 mutex_unlock(&fs_devices->device_list_mutex);
1039 return ERR_PTR(-ENOMEM);
1040 }
1041 rcu_string_free(device->name);
1042 rcu_assign_pointer(device->name, name);
1043 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
1044 fs_devices->missing_devices--;
1045 clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1046 }
1047 device->devt = path_devt;
1048 }
1049
1050 /*
1051 * Unmount does not free the btrfs_device struct but would zero
1052 * generation along with most of the other members. So just update
1053 * it back. We need it to pick the disk with largest generation
1054 * (as above).
1055 */
1056 if (!fs_devices->opened) {
1057 device->generation = found_transid;
1058 fs_devices->latest_generation = max_t(u64, found_transid,
1059 fs_devices->latest_generation);
1060 }
1061
1062 fs_devices->total_devices = btrfs_super_num_devices(disk_super);
1063
1064 mutex_unlock(&fs_devices->device_list_mutex);
1065 return device;
1066 }
1067
clone_fs_devices(struct btrfs_fs_devices * orig)1068 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
1069 {
1070 struct btrfs_fs_devices *fs_devices;
1071 struct btrfs_device *device;
1072 struct btrfs_device *orig_dev;
1073 int ret = 0;
1074
1075 lockdep_assert_held(&uuid_mutex);
1076
1077 fs_devices = alloc_fs_devices(orig->fsid);
1078 if (IS_ERR(fs_devices))
1079 return fs_devices;
1080
1081 fs_devices->total_devices = orig->total_devices;
1082
1083 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
1084 const char *dev_path = NULL;
1085
1086 /*
1087 * This is ok to do without RCU read locked because we hold the
1088 * uuid mutex so nothing we touch in here is going to disappear.
1089 */
1090 if (orig_dev->name)
1091 dev_path = orig_dev->name->str;
1092
1093 device = btrfs_alloc_device(NULL, &orig_dev->devid,
1094 orig_dev->uuid, dev_path);
1095 if (IS_ERR(device)) {
1096 ret = PTR_ERR(device);
1097 goto error;
1098 }
1099
1100 if (orig_dev->zone_info) {
1101 struct btrfs_zoned_device_info *zone_info;
1102
1103 zone_info = btrfs_clone_dev_zone_info(orig_dev);
1104 if (!zone_info) {
1105 btrfs_free_device(device);
1106 ret = -ENOMEM;
1107 goto error;
1108 }
1109 device->zone_info = zone_info;
1110 }
1111
1112 list_add(&device->dev_list, &fs_devices->devices);
1113 device->fs_devices = fs_devices;
1114 fs_devices->num_devices++;
1115 }
1116 return fs_devices;
1117 error:
1118 free_fs_devices(fs_devices);
1119 return ERR_PTR(ret);
1120 }
1121
__btrfs_free_extra_devids(struct btrfs_fs_devices * fs_devices,struct btrfs_device ** latest_dev)1122 static void __btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices,
1123 struct btrfs_device **latest_dev)
1124 {
1125 struct btrfs_device *device, *next;
1126
1127 /* This is the initialized path, it is safe to release the devices. */
1128 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
1129 if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state)) {
1130 if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT,
1131 &device->dev_state) &&
1132 !test_bit(BTRFS_DEV_STATE_MISSING,
1133 &device->dev_state) &&
1134 (!*latest_dev ||
1135 device->generation > (*latest_dev)->generation)) {
1136 *latest_dev = device;
1137 }
1138 continue;
1139 }
1140
1141 /*
1142 * We have already validated the presence of BTRFS_DEV_REPLACE_DEVID,
1143 * in btrfs_init_dev_replace() so just continue.
1144 */
1145 if (device->devid == BTRFS_DEV_REPLACE_DEVID)
1146 continue;
1147
1148 if (device->bdev_file) {
1149 fput(device->bdev_file);
1150 device->bdev = NULL;
1151 device->bdev_file = NULL;
1152 fs_devices->open_devices--;
1153 }
1154 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1155 list_del_init(&device->dev_alloc_list);
1156 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1157 fs_devices->rw_devices--;
1158 }
1159 list_del_init(&device->dev_list);
1160 fs_devices->num_devices--;
1161 btrfs_free_device(device);
1162 }
1163
1164 }
1165
1166 /*
1167 * After we have read the system tree and know devids belonging to this
1168 * filesystem, remove the device which does not belong there.
1169 */
btrfs_free_extra_devids(struct btrfs_fs_devices * fs_devices)1170 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices)
1171 {
1172 struct btrfs_device *latest_dev = NULL;
1173 struct btrfs_fs_devices *seed_dev;
1174
1175 mutex_lock(&uuid_mutex);
1176 __btrfs_free_extra_devids(fs_devices, &latest_dev);
1177
1178 list_for_each_entry(seed_dev, &fs_devices->seed_list, seed_list)
1179 __btrfs_free_extra_devids(seed_dev, &latest_dev);
1180
1181 fs_devices->latest_dev = latest_dev;
1182
1183 mutex_unlock(&uuid_mutex);
1184 }
1185
btrfs_close_bdev(struct btrfs_device * device)1186 static void btrfs_close_bdev(struct btrfs_device *device)
1187 {
1188 if (!device->bdev)
1189 return;
1190
1191 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1192 sync_blockdev(device->bdev);
1193 invalidate_bdev(device->bdev);
1194 }
1195
1196 fput(device->bdev_file);
1197 }
1198
btrfs_close_one_device(struct btrfs_device * device)1199 static void btrfs_close_one_device(struct btrfs_device *device)
1200 {
1201 struct btrfs_fs_devices *fs_devices = device->fs_devices;
1202
1203 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
1204 device->devid != BTRFS_DEV_REPLACE_DEVID) {
1205 list_del_init(&device->dev_alloc_list);
1206 fs_devices->rw_devices--;
1207 }
1208
1209 if (device->devid == BTRFS_DEV_REPLACE_DEVID)
1210 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1211
1212 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
1213 clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1214 fs_devices->missing_devices--;
1215 }
1216
1217 btrfs_close_bdev(device);
1218 if (device->bdev) {
1219 fs_devices->open_devices--;
1220 device->bdev = NULL;
1221 device->bdev_file = NULL;
1222 }
1223 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1224 btrfs_destroy_dev_zone_info(device);
1225
1226 device->fs_info = NULL;
1227 atomic_set(&device->dev_stats_ccnt, 0);
1228 extent_io_tree_release(&device->alloc_state);
1229
1230 /*
1231 * Reset the flush error record. We might have a transient flush error
1232 * in this mount, and if so we aborted the current transaction and set
1233 * the fs to an error state, guaranteeing no super blocks can be further
1234 * committed. However that error might be transient and if we unmount the
1235 * filesystem and mount it again, we should allow the mount to succeed
1236 * (btrfs_check_rw_degradable() should not fail) - if after mounting the
1237 * filesystem again we still get flush errors, then we will again abort
1238 * any transaction and set the error state, guaranteeing no commits of
1239 * unsafe super blocks.
1240 */
1241 device->last_flush_error = 0;
1242
1243 /* Verify the device is back in a pristine state */
1244 WARN_ON(test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state));
1245 WARN_ON(test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state));
1246 WARN_ON(!list_empty(&device->dev_alloc_list));
1247 WARN_ON(!list_empty(&device->post_commit_list));
1248 }
1249
close_fs_devices(struct btrfs_fs_devices * fs_devices)1250 static void close_fs_devices(struct btrfs_fs_devices *fs_devices)
1251 {
1252 struct btrfs_device *device, *tmp;
1253
1254 lockdep_assert_held(&uuid_mutex);
1255
1256 if (--fs_devices->opened > 0)
1257 return;
1258
1259 list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list)
1260 btrfs_close_one_device(device);
1261
1262 WARN_ON(fs_devices->open_devices);
1263 WARN_ON(fs_devices->rw_devices);
1264 fs_devices->opened = 0;
1265 fs_devices->seeding = false;
1266 fs_devices->fs_info = NULL;
1267 }
1268
btrfs_close_devices(struct btrfs_fs_devices * fs_devices)1269 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
1270 {
1271 LIST_HEAD(list);
1272 struct btrfs_fs_devices *tmp;
1273
1274 mutex_lock(&uuid_mutex);
1275 close_fs_devices(fs_devices);
1276 if (!fs_devices->opened) {
1277 list_splice_init(&fs_devices->seed_list, &list);
1278
1279 /*
1280 * If the struct btrfs_fs_devices is not assembled with any
1281 * other device, it can be re-initialized during the next mount
1282 * without the needing device-scan step. Therefore, it can be
1283 * fully freed.
1284 */
1285 if (fs_devices->num_devices == 1) {
1286 list_del(&fs_devices->fs_list);
1287 free_fs_devices(fs_devices);
1288 }
1289 }
1290
1291
1292 list_for_each_entry_safe(fs_devices, tmp, &list, seed_list) {
1293 close_fs_devices(fs_devices);
1294 list_del(&fs_devices->seed_list);
1295 free_fs_devices(fs_devices);
1296 }
1297 mutex_unlock(&uuid_mutex);
1298 }
1299
open_fs_devices(struct btrfs_fs_devices * fs_devices,blk_mode_t flags,void * holder)1300 static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
1301 blk_mode_t flags, void *holder)
1302 {
1303 struct btrfs_device *device;
1304 struct btrfs_device *latest_dev = NULL;
1305 struct btrfs_device *tmp_device;
1306 s64 __maybe_unused value = 0;
1307 int ret = 0;
1308
1309 list_for_each_entry_safe(device, tmp_device, &fs_devices->devices,
1310 dev_list) {
1311 int ret2;
1312
1313 ret2 = btrfs_open_one_device(fs_devices, device, flags, holder);
1314 if (ret2 == 0 &&
1315 (!latest_dev || device->generation > latest_dev->generation)) {
1316 latest_dev = device;
1317 } else if (ret2 == -ENODATA) {
1318 fs_devices->num_devices--;
1319 list_del(&device->dev_list);
1320 btrfs_free_device(device);
1321 }
1322 if (ret == 0 && ret2 != 0)
1323 ret = ret2;
1324 }
1325
1326 if (fs_devices->open_devices == 0) {
1327 if (ret)
1328 return ret;
1329 return -EINVAL;
1330 }
1331
1332 fs_devices->opened = 1;
1333 fs_devices->latest_dev = latest_dev;
1334 fs_devices->total_rw_bytes = 0;
1335 fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_REGULAR;
1336 #ifdef CONFIG_BTRFS_EXPERIMENTAL
1337 fs_devices->rr_min_contig_read = BTRFS_DEFAULT_RR_MIN_CONTIG_READ;
1338 fs_devices->read_devid = latest_dev->devid;
1339 fs_devices->read_policy = btrfs_read_policy_to_enum(btrfs_get_mod_read_policy(),
1340 &value);
1341 if (fs_devices->read_policy == BTRFS_READ_POLICY_RR)
1342 fs_devices->collect_fs_stats = true;
1343
1344 if (value) {
1345 if (fs_devices->read_policy == BTRFS_READ_POLICY_RR)
1346 fs_devices->rr_min_contig_read = value;
1347 if (fs_devices->read_policy == BTRFS_READ_POLICY_DEVID)
1348 fs_devices->read_devid = value;
1349 }
1350 #else
1351 fs_devices->read_policy = BTRFS_READ_POLICY_PID;
1352 #endif
1353
1354 return 0;
1355 }
1356
devid_cmp(void * priv,const struct list_head * a,const struct list_head * b)1357 static int devid_cmp(void *priv, const struct list_head *a,
1358 const struct list_head *b)
1359 {
1360 const struct btrfs_device *dev1, *dev2;
1361
1362 dev1 = list_entry(a, struct btrfs_device, dev_list);
1363 dev2 = list_entry(b, struct btrfs_device, dev_list);
1364
1365 if (dev1->devid < dev2->devid)
1366 return -1;
1367 else if (dev1->devid > dev2->devid)
1368 return 1;
1369 return 0;
1370 }
1371
btrfs_open_devices(struct btrfs_fs_devices * fs_devices,blk_mode_t flags,void * holder)1372 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
1373 blk_mode_t flags, void *holder)
1374 {
1375 int ret;
1376
1377 lockdep_assert_held(&uuid_mutex);
1378 /*
1379 * The device_list_mutex cannot be taken here in case opening the
1380 * underlying device takes further locks like open_mutex.
1381 *
1382 * We also don't need the lock here as this is called during mount and
1383 * exclusion is provided by uuid_mutex
1384 */
1385
1386 if (fs_devices->opened) {
1387 fs_devices->opened++;
1388 ret = 0;
1389 } else {
1390 list_sort(NULL, &fs_devices->devices, devid_cmp);
1391 ret = open_fs_devices(fs_devices, flags, holder);
1392 }
1393
1394 return ret;
1395 }
1396
btrfs_release_disk_super(struct btrfs_super_block * super)1397 void btrfs_release_disk_super(struct btrfs_super_block *super)
1398 {
1399 struct page *page = virt_to_page(super);
1400
1401 put_page(page);
1402 }
1403
btrfs_read_disk_super(struct block_device * bdev,u64 bytenr,u64 bytenr_orig)1404 static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev,
1405 u64 bytenr, u64 bytenr_orig)
1406 {
1407 struct btrfs_super_block *disk_super;
1408 struct page *page;
1409 void *p;
1410 pgoff_t index;
1411
1412 /* make sure our super fits in the device */
1413 if (bytenr + PAGE_SIZE >= bdev_nr_bytes(bdev))
1414 return ERR_PTR(-EINVAL);
1415
1416 /* make sure our super fits in the page */
1417 if (sizeof(*disk_super) > PAGE_SIZE)
1418 return ERR_PTR(-EINVAL);
1419
1420 /* make sure our super doesn't straddle pages on disk */
1421 index = bytenr >> PAGE_SHIFT;
1422 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index)
1423 return ERR_PTR(-EINVAL);
1424
1425 /* pull in the page with our super */
1426 page = read_cache_page_gfp(bdev->bd_mapping, index, GFP_KERNEL);
1427
1428 if (IS_ERR(page))
1429 return ERR_CAST(page);
1430
1431 p = page_address(page);
1432
1433 /* align our pointer to the offset of the super block */
1434 disk_super = p + offset_in_page(bytenr);
1435
1436 if (btrfs_super_bytenr(disk_super) != bytenr_orig ||
1437 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1438 btrfs_release_disk_super(p);
1439 return ERR_PTR(-EINVAL);
1440 }
1441
1442 if (disk_super->label[0] && disk_super->label[BTRFS_LABEL_SIZE - 1])
1443 disk_super->label[BTRFS_LABEL_SIZE - 1] = 0;
1444
1445 return disk_super;
1446 }
1447
btrfs_forget_devices(dev_t devt)1448 int btrfs_forget_devices(dev_t devt)
1449 {
1450 int ret;
1451
1452 mutex_lock(&uuid_mutex);
1453 ret = btrfs_free_stale_devices(devt, NULL);
1454 mutex_unlock(&uuid_mutex);
1455
1456 return ret;
1457 }
1458
btrfs_skip_registration(struct btrfs_super_block * disk_super,const char * path,dev_t devt,bool mount_arg_dev)1459 static bool btrfs_skip_registration(struct btrfs_super_block *disk_super,
1460 const char *path, dev_t devt,
1461 bool mount_arg_dev)
1462 {
1463 struct btrfs_fs_devices *fs_devices;
1464
1465 /*
1466 * Do not skip device registration for mounted devices with matching
1467 * maj:min but different paths. Booting without initrd relies on
1468 * /dev/root initially, later replaced with the actual root device.
1469 * A successful scan ensures grub2-probe selects the correct device.
1470 */
1471 list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
1472 struct btrfs_device *device;
1473
1474 mutex_lock(&fs_devices->device_list_mutex);
1475
1476 if (!fs_devices->opened) {
1477 mutex_unlock(&fs_devices->device_list_mutex);
1478 continue;
1479 }
1480
1481 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1482 if (device->bdev && (device->bdev->bd_dev == devt) &&
1483 strcmp(device->name->str, path) != 0) {
1484 mutex_unlock(&fs_devices->device_list_mutex);
1485
1486 /* Do not skip registration. */
1487 return false;
1488 }
1489 }
1490 mutex_unlock(&fs_devices->device_list_mutex);
1491 }
1492
1493 if (!mount_arg_dev && btrfs_super_num_devices(disk_super) == 1 &&
1494 !(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING))
1495 return true;
1496
1497 return false;
1498 }
1499
1500 /*
1501 * Look for a btrfs signature on a device. This may be called out of the mount path
1502 * and we are not allowed to call set_blocksize during the scan. The superblock
1503 * is read via pagecache.
1504 *
1505 * With @mount_arg_dev it's a scan during mount time that will always register
1506 * the device or return an error. Multi-device and seeding devices are registered
1507 * in both cases.
1508 */
btrfs_scan_one_device(const char * path,blk_mode_t flags,bool mount_arg_dev)1509 struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
1510 bool mount_arg_dev)
1511 {
1512 struct btrfs_super_block *disk_super;
1513 bool new_device_added = false;
1514 struct btrfs_device *device = NULL;
1515 struct file *bdev_file;
1516 char *canonical_path = NULL;
1517 u64 bytenr;
1518 dev_t devt;
1519 int ret;
1520
1521 lockdep_assert_held(&uuid_mutex);
1522
1523 if (!is_good_dev_path(path)) {
1524 canonical_path = kmalloc(PATH_MAX, GFP_KERNEL);
1525 if (canonical_path) {
1526 ret = get_canonical_dev_path(path, canonical_path);
1527 if (ret < 0) {
1528 kfree(canonical_path);
1529 canonical_path = NULL;
1530 }
1531 }
1532 }
1533 /*
1534 * Avoid an exclusive open here, as the systemd-udev may initiate the
1535 * device scan which may race with the user's mount or mkfs command,
1536 * resulting in failure.
1537 * Since the device scan is solely for reading purposes, there is no
1538 * need for an exclusive open. Additionally, the devices are read again
1539 * during the mount process. It is ok to get some inconsistent
1540 * values temporarily, as the device paths of the fsid are the only
1541 * required information for assembling the volume.
1542 */
1543 bdev_file = bdev_file_open_by_path(path, flags, NULL, NULL);
1544 if (IS_ERR(bdev_file))
1545 return ERR_CAST(bdev_file);
1546
1547 /*
1548 * We would like to check all the super blocks, but doing so would
1549 * allow a mount to succeed after a mkfs from a different filesystem.
1550 * Currently, recovery from a bad primary btrfs superblock is done
1551 * using the userspace command 'btrfs check --super'.
1552 */
1553 ret = btrfs_sb_log_location_bdev(file_bdev(bdev_file), 0, READ, &bytenr);
1554 if (ret) {
1555 device = ERR_PTR(ret);
1556 goto error_bdev_put;
1557 }
1558
1559 disk_super = btrfs_read_disk_super(file_bdev(bdev_file), bytenr,
1560 btrfs_sb_offset(0));
1561 if (IS_ERR(disk_super)) {
1562 device = ERR_CAST(disk_super);
1563 goto error_bdev_put;
1564 }
1565
1566 devt = file_bdev(bdev_file)->bd_dev;
1567 if (btrfs_skip_registration(disk_super, path, devt, mount_arg_dev)) {
1568 pr_debug("BTRFS: skip registering single non-seed device %s (%d:%d)\n",
1569 path, MAJOR(devt), MINOR(devt));
1570
1571 btrfs_free_stale_devices(devt, NULL);
1572
1573 device = NULL;
1574 goto free_disk_super;
1575 }
1576
1577 device = device_list_add(canonical_path ? : path, disk_super,
1578 &new_device_added);
1579 if (!IS_ERR(device) && new_device_added)
1580 btrfs_free_stale_devices(device->devt, device);
1581
1582 free_disk_super:
1583 btrfs_release_disk_super(disk_super);
1584
1585 error_bdev_put:
1586 fput(bdev_file);
1587 kfree(canonical_path);
1588
1589 return device;
1590 }
1591
1592 /*
1593 * Try to find a chunk that intersects [start, start + len] range and when one
1594 * such is found, record the end of it in *start
1595 */
contains_pending_extent(struct btrfs_device * device,u64 * start,u64 len)1596 static bool contains_pending_extent(struct btrfs_device *device, u64 *start,
1597 u64 len)
1598 {
1599 u64 physical_start, physical_end;
1600
1601 lockdep_assert_held(&device->fs_info->chunk_mutex);
1602
1603 if (find_first_extent_bit(&device->alloc_state, *start,
1604 &physical_start, &physical_end,
1605 CHUNK_ALLOCATED, NULL)) {
1606
1607 if (in_range(physical_start, *start, len) ||
1608 in_range(*start, physical_start,
1609 physical_end + 1 - physical_start)) {
1610 *start = physical_end + 1;
1611 return true;
1612 }
1613 }
1614 return false;
1615 }
1616
dev_extent_search_start(struct btrfs_device * device)1617 static u64 dev_extent_search_start(struct btrfs_device *device)
1618 {
1619 switch (device->fs_devices->chunk_alloc_policy) {
1620 case BTRFS_CHUNK_ALLOC_REGULAR:
1621 return BTRFS_DEVICE_RANGE_RESERVED;
1622 case BTRFS_CHUNK_ALLOC_ZONED:
1623 /*
1624 * We don't care about the starting region like regular
1625 * allocator, because we anyway use/reserve the first two zones
1626 * for superblock logging.
1627 */
1628 return 0;
1629 default:
1630 BUG();
1631 }
1632 }
1633
dev_extent_hole_check_zoned(struct btrfs_device * device,u64 * hole_start,u64 * hole_size,u64 num_bytes)1634 static bool dev_extent_hole_check_zoned(struct btrfs_device *device,
1635 u64 *hole_start, u64 *hole_size,
1636 u64 num_bytes)
1637 {
1638 u64 zone_size = device->zone_info->zone_size;
1639 u64 pos;
1640 int ret;
1641 bool changed = false;
1642
1643 ASSERT(IS_ALIGNED(*hole_start, zone_size));
1644
1645 while (*hole_size > 0) {
1646 pos = btrfs_find_allocatable_zones(device, *hole_start,
1647 *hole_start + *hole_size,
1648 num_bytes);
1649 if (pos != *hole_start) {
1650 *hole_size = *hole_start + *hole_size - pos;
1651 *hole_start = pos;
1652 changed = true;
1653 if (*hole_size < num_bytes)
1654 break;
1655 }
1656
1657 ret = btrfs_ensure_empty_zones(device, pos, num_bytes);
1658
1659 /* Range is ensured to be empty */
1660 if (!ret)
1661 return changed;
1662
1663 /* Given hole range was invalid (outside of device) */
1664 if (ret == -ERANGE) {
1665 *hole_start += *hole_size;
1666 *hole_size = 0;
1667 return true;
1668 }
1669
1670 *hole_start += zone_size;
1671 *hole_size -= zone_size;
1672 changed = true;
1673 }
1674
1675 return changed;
1676 }
1677
1678 /*
1679 * Check if specified hole is suitable for allocation.
1680 *
1681 * @device: the device which we have the hole
1682 * @hole_start: starting position of the hole
1683 * @hole_size: the size of the hole
1684 * @num_bytes: the size of the free space that we need
1685 *
1686 * This function may modify @hole_start and @hole_size to reflect the suitable
1687 * position for allocation. Returns 1 if hole position is updated, 0 otherwise.
1688 */
dev_extent_hole_check(struct btrfs_device * device,u64 * hole_start,u64 * hole_size,u64 num_bytes)1689 static bool dev_extent_hole_check(struct btrfs_device *device, u64 *hole_start,
1690 u64 *hole_size, u64 num_bytes)
1691 {
1692 bool changed = false;
1693 u64 hole_end = *hole_start + *hole_size;
1694
1695 for (;;) {
1696 /*
1697 * Check before we set max_hole_start, otherwise we could end up
1698 * sending back this offset anyway.
1699 */
1700 if (contains_pending_extent(device, hole_start, *hole_size)) {
1701 if (hole_end >= *hole_start)
1702 *hole_size = hole_end - *hole_start;
1703 else
1704 *hole_size = 0;
1705 changed = true;
1706 }
1707
1708 switch (device->fs_devices->chunk_alloc_policy) {
1709 case BTRFS_CHUNK_ALLOC_REGULAR:
1710 /* No extra check */
1711 break;
1712 case BTRFS_CHUNK_ALLOC_ZONED:
1713 if (dev_extent_hole_check_zoned(device, hole_start,
1714 hole_size, num_bytes)) {
1715 changed = true;
1716 /*
1717 * The changed hole can contain pending extent.
1718 * Loop again to check that.
1719 */
1720 continue;
1721 }
1722 break;
1723 default:
1724 BUG();
1725 }
1726
1727 break;
1728 }
1729
1730 return changed;
1731 }
1732
1733 /*
1734 * Find free space in the specified device.
1735 *
1736 * @device: the device which we search the free space in
1737 * @num_bytes: the size of the free space that we need
1738 * @search_start: the position from which to begin the search
1739 * @start: store the start of the free space.
1740 * @len: the size of the free space. that we find, or the size
1741 * of the max free space if we don't find suitable free space
1742 *
1743 * This does a pretty simple search, the expectation is that it is called very
1744 * infrequently and that a given device has a small number of extents.
1745 *
1746 * @start is used to store the start of the free space if we find. But if we
1747 * don't find suitable free space, it will be used to store the start position
1748 * of the max free space.
1749 *
1750 * @len is used to store the size of the free space that we find.
1751 * But if we don't find suitable free space, it is used to store the size of
1752 * the max free space.
1753 *
1754 * NOTE: This function will search *commit* root of device tree, and does extra
1755 * check to ensure dev extents are not double allocated.
1756 * This makes the function safe to allocate dev extents but may not report
1757 * correct usable device space, as device extent freed in current transaction
1758 * is not reported as available.
1759 */
find_free_dev_extent(struct btrfs_device * device,u64 num_bytes,u64 * start,u64 * len)1760 static int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
1761 u64 *start, u64 *len)
1762 {
1763 struct btrfs_fs_info *fs_info = device->fs_info;
1764 struct btrfs_root *root = fs_info->dev_root;
1765 struct btrfs_key key;
1766 struct btrfs_dev_extent *dev_extent;
1767 struct btrfs_path *path;
1768 u64 search_start;
1769 u64 hole_size;
1770 u64 max_hole_start;
1771 u64 max_hole_size = 0;
1772 u64 extent_end;
1773 u64 search_end = device->total_bytes;
1774 int ret;
1775 int slot;
1776 struct extent_buffer *l;
1777
1778 search_start = dev_extent_search_start(device);
1779 max_hole_start = search_start;
1780
1781 WARN_ON(device->zone_info &&
1782 !IS_ALIGNED(num_bytes, device->zone_info->zone_size));
1783
1784 path = btrfs_alloc_path();
1785 if (!path) {
1786 ret = -ENOMEM;
1787 goto out;
1788 }
1789 again:
1790 if (search_start >= search_end ||
1791 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1792 ret = -ENOSPC;
1793 goto out;
1794 }
1795
1796 path->reada = READA_FORWARD;
1797 path->search_commit_root = 1;
1798 path->skip_locking = 1;
1799
1800 key.objectid = device->devid;
1801 key.offset = search_start;
1802 key.type = BTRFS_DEV_EXTENT_KEY;
1803
1804 ret = btrfs_search_backwards(root, &key, path);
1805 if (ret < 0)
1806 goto out;
1807
1808 while (search_start < search_end) {
1809 l = path->nodes[0];
1810 slot = path->slots[0];
1811 if (slot >= btrfs_header_nritems(l)) {
1812 ret = btrfs_next_leaf(root, path);
1813 if (ret == 0)
1814 continue;
1815 if (ret < 0)
1816 goto out;
1817
1818 break;
1819 }
1820 btrfs_item_key_to_cpu(l, &key, slot);
1821
1822 if (key.objectid < device->devid)
1823 goto next;
1824
1825 if (key.objectid > device->devid)
1826 break;
1827
1828 if (key.type != BTRFS_DEV_EXTENT_KEY)
1829 goto next;
1830
1831 if (key.offset > search_end)
1832 break;
1833
1834 if (key.offset > search_start) {
1835 hole_size = key.offset - search_start;
1836 dev_extent_hole_check(device, &search_start, &hole_size,
1837 num_bytes);
1838
1839 if (hole_size > max_hole_size) {
1840 max_hole_start = search_start;
1841 max_hole_size = hole_size;
1842 }
1843
1844 /*
1845 * If this free space is greater than which we need,
1846 * it must be the max free space that we have found
1847 * until now, so max_hole_start must point to the start
1848 * of this free space and the length of this free space
1849 * is stored in max_hole_size. Thus, we return
1850 * max_hole_start and max_hole_size and go back to the
1851 * caller.
1852 */
1853 if (hole_size >= num_bytes) {
1854 ret = 0;
1855 goto out;
1856 }
1857 }
1858
1859 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1860 extent_end = key.offset + btrfs_dev_extent_length(l,
1861 dev_extent);
1862 if (extent_end > search_start)
1863 search_start = extent_end;
1864 next:
1865 path->slots[0]++;
1866 cond_resched();
1867 }
1868
1869 /*
1870 * At this point, search_start should be the end of
1871 * allocated dev extents, and when shrinking the device,
1872 * search_end may be smaller than search_start.
1873 */
1874 if (search_end > search_start) {
1875 hole_size = search_end - search_start;
1876 if (dev_extent_hole_check(device, &search_start, &hole_size,
1877 num_bytes)) {
1878 btrfs_release_path(path);
1879 goto again;
1880 }
1881
1882 if (hole_size > max_hole_size) {
1883 max_hole_start = search_start;
1884 max_hole_size = hole_size;
1885 }
1886 }
1887
1888 /* See above. */
1889 if (max_hole_size < num_bytes)
1890 ret = -ENOSPC;
1891 else
1892 ret = 0;
1893
1894 ASSERT(max_hole_start + max_hole_size <= search_end);
1895 out:
1896 btrfs_free_path(path);
1897 *start = max_hole_start;
1898 if (len)
1899 *len = max_hole_size;
1900 return ret;
1901 }
1902
btrfs_free_dev_extent(struct btrfs_trans_handle * trans,struct btrfs_device * device,u64 start,u64 * dev_extent_len)1903 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1904 struct btrfs_device *device,
1905 u64 start, u64 *dev_extent_len)
1906 {
1907 struct btrfs_fs_info *fs_info = device->fs_info;
1908 struct btrfs_root *root = fs_info->dev_root;
1909 int ret;
1910 struct btrfs_path *path;
1911 struct btrfs_key key;
1912 struct btrfs_key found_key;
1913 struct extent_buffer *leaf = NULL;
1914 struct btrfs_dev_extent *extent = NULL;
1915
1916 path = btrfs_alloc_path();
1917 if (!path)
1918 return -ENOMEM;
1919
1920 key.objectid = device->devid;
1921 key.offset = start;
1922 key.type = BTRFS_DEV_EXTENT_KEY;
1923 again:
1924 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1925 if (ret > 0) {
1926 ret = btrfs_previous_item(root, path, key.objectid,
1927 BTRFS_DEV_EXTENT_KEY);
1928 if (ret)
1929 goto out;
1930 leaf = path->nodes[0];
1931 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1932 extent = btrfs_item_ptr(leaf, path->slots[0],
1933 struct btrfs_dev_extent);
1934 BUG_ON(found_key.offset > start || found_key.offset +
1935 btrfs_dev_extent_length(leaf, extent) < start);
1936 key = found_key;
1937 btrfs_release_path(path);
1938 goto again;
1939 } else if (ret == 0) {
1940 leaf = path->nodes[0];
1941 extent = btrfs_item_ptr(leaf, path->slots[0],
1942 struct btrfs_dev_extent);
1943 } else {
1944 goto out;
1945 }
1946
1947 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1948
1949 ret = btrfs_del_item(trans, root, path);
1950 if (ret == 0)
1951 set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
1952 out:
1953 btrfs_free_path(path);
1954 return ret;
1955 }
1956
find_next_chunk(struct btrfs_fs_info * fs_info)1957 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1958 {
1959 struct rb_node *n;
1960 u64 ret = 0;
1961
1962 read_lock(&fs_info->mapping_tree_lock);
1963 n = rb_last(&fs_info->mapping_tree.rb_root);
1964 if (n) {
1965 struct btrfs_chunk_map *map;
1966
1967 map = rb_entry(n, struct btrfs_chunk_map, rb_node);
1968 ret = map->start + map->chunk_len;
1969 }
1970 read_unlock(&fs_info->mapping_tree_lock);
1971
1972 return ret;
1973 }
1974
find_next_devid(struct btrfs_fs_info * fs_info,u64 * devid_ret)1975 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1976 u64 *devid_ret)
1977 {
1978 int ret;
1979 struct btrfs_key key;
1980 struct btrfs_key found_key;
1981 struct btrfs_path *path;
1982
1983 path = btrfs_alloc_path();
1984 if (!path)
1985 return -ENOMEM;
1986
1987 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1988 key.type = BTRFS_DEV_ITEM_KEY;
1989 key.offset = (u64)-1;
1990
1991 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1992 if (ret < 0)
1993 goto error;
1994
1995 if (ret == 0) {
1996 /* Corruption */
1997 btrfs_err(fs_info, "corrupted chunk tree devid -1 matched");
1998 ret = -EUCLEAN;
1999 goto error;
2000 }
2001
2002 ret = btrfs_previous_item(fs_info->chunk_root, path,
2003 BTRFS_DEV_ITEMS_OBJECTID,
2004 BTRFS_DEV_ITEM_KEY);
2005 if (ret) {
2006 *devid_ret = 1;
2007 } else {
2008 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2009 path->slots[0]);
2010 *devid_ret = found_key.offset + 1;
2011 }
2012 ret = 0;
2013 error:
2014 btrfs_free_path(path);
2015 return ret;
2016 }
2017
2018 /*
2019 * the device information is stored in the chunk root
2020 * the btrfs_device struct should be fully filled in
2021 */
btrfs_add_dev_item(struct btrfs_trans_handle * trans,struct btrfs_device * device)2022 static int btrfs_add_dev_item(struct btrfs_trans_handle *trans,
2023 struct btrfs_device *device)
2024 {
2025 int ret;
2026 struct btrfs_path *path;
2027 struct btrfs_dev_item *dev_item;
2028 struct extent_buffer *leaf;
2029 struct btrfs_key key;
2030 unsigned long ptr;
2031
2032 path = btrfs_alloc_path();
2033 if (!path)
2034 return -ENOMEM;
2035
2036 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2037 key.type = BTRFS_DEV_ITEM_KEY;
2038 key.offset = device->devid;
2039
2040 btrfs_reserve_chunk_metadata(trans, true);
2041 ret = btrfs_insert_empty_item(trans, trans->fs_info->chunk_root, path,
2042 &key, sizeof(*dev_item));
2043 btrfs_trans_release_chunk_metadata(trans);
2044 if (ret)
2045 goto out;
2046
2047 leaf = path->nodes[0];
2048 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2049
2050 btrfs_set_device_id(leaf, dev_item, device->devid);
2051 btrfs_set_device_generation(leaf, dev_item, 0);
2052 btrfs_set_device_type(leaf, dev_item, device->type);
2053 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2054 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2055 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2056 btrfs_set_device_total_bytes(leaf, dev_item,
2057 btrfs_device_get_disk_total_bytes(device));
2058 btrfs_set_device_bytes_used(leaf, dev_item,
2059 btrfs_device_get_bytes_used(device));
2060 btrfs_set_device_group(leaf, dev_item, 0);
2061 btrfs_set_device_seek_speed(leaf, dev_item, 0);
2062 btrfs_set_device_bandwidth(leaf, dev_item, 0);
2063 btrfs_set_device_start_offset(leaf, dev_item, 0);
2064
2065 ptr = btrfs_device_uuid(dev_item);
2066 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
2067 ptr = btrfs_device_fsid(dev_item);
2068 write_extent_buffer(leaf, trans->fs_info->fs_devices->metadata_uuid,
2069 ptr, BTRFS_FSID_SIZE);
2070
2071 ret = 0;
2072 out:
2073 btrfs_free_path(path);
2074 return ret;
2075 }
2076
2077 /*
2078 * Function to update ctime/mtime for a given device path.
2079 * Mainly used for ctime/mtime based probe like libblkid.
2080 *
2081 * We don't care about errors here, this is just to be kind to userspace.
2082 */
update_dev_time(const char * device_path)2083 static void update_dev_time(const char *device_path)
2084 {
2085 struct path path;
2086 int ret;
2087
2088 ret = kern_path(device_path, LOOKUP_FOLLOW, &path);
2089 if (ret)
2090 return;
2091
2092 inode_update_time(d_inode(path.dentry), S_MTIME | S_CTIME | S_VERSION);
2093 path_put(&path);
2094 }
2095
btrfs_rm_dev_item(struct btrfs_trans_handle * trans,struct btrfs_device * device)2096 static int btrfs_rm_dev_item(struct btrfs_trans_handle *trans,
2097 struct btrfs_device *device)
2098 {
2099 struct btrfs_root *root = device->fs_info->chunk_root;
2100 int ret;
2101 struct btrfs_path *path;
2102 struct btrfs_key key;
2103
2104 path = btrfs_alloc_path();
2105 if (!path)
2106 return -ENOMEM;
2107
2108 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2109 key.type = BTRFS_DEV_ITEM_KEY;
2110 key.offset = device->devid;
2111
2112 btrfs_reserve_chunk_metadata(trans, false);
2113 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2114 btrfs_trans_release_chunk_metadata(trans);
2115 if (ret) {
2116 if (ret > 0)
2117 ret = -ENOENT;
2118 goto out;
2119 }
2120
2121 ret = btrfs_del_item(trans, root, path);
2122 out:
2123 btrfs_free_path(path);
2124 return ret;
2125 }
2126
2127 /*
2128 * Verify that @num_devices satisfies the RAID profile constraints in the whole
2129 * filesystem. It's up to the caller to adjust that number regarding eg. device
2130 * replace.
2131 */
btrfs_check_raid_min_devices(struct btrfs_fs_info * fs_info,u64 num_devices)2132 static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
2133 u64 num_devices)
2134 {
2135 u64 all_avail;
2136 unsigned seq;
2137 int i;
2138
2139 do {
2140 seq = read_seqbegin(&fs_info->profiles_lock);
2141
2142 all_avail = fs_info->avail_data_alloc_bits |
2143 fs_info->avail_system_alloc_bits |
2144 fs_info->avail_metadata_alloc_bits;
2145 } while (read_seqretry(&fs_info->profiles_lock, seq));
2146
2147 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
2148 if (!(all_avail & btrfs_raid_array[i].bg_flag))
2149 continue;
2150
2151 if (num_devices < btrfs_raid_array[i].devs_min)
2152 return btrfs_raid_array[i].mindev_error;
2153 }
2154
2155 return 0;
2156 }
2157
btrfs_find_next_active_device(struct btrfs_fs_devices * fs_devs,struct btrfs_device * device)2158 static struct btrfs_device * btrfs_find_next_active_device(
2159 struct btrfs_fs_devices *fs_devs, struct btrfs_device *device)
2160 {
2161 struct btrfs_device *next_device;
2162
2163 list_for_each_entry(next_device, &fs_devs->devices, dev_list) {
2164 if (next_device != device &&
2165 !test_bit(BTRFS_DEV_STATE_MISSING, &next_device->dev_state)
2166 && next_device->bdev)
2167 return next_device;
2168 }
2169
2170 return NULL;
2171 }
2172
2173 /*
2174 * Helper function to check if the given device is part of s_bdev / latest_dev
2175 * and replace it with the provided or the next active device, in the context
2176 * where this function called, there should be always be another device (or
2177 * this_dev) which is active.
2178 */
btrfs_assign_next_active_device(struct btrfs_device * device,struct btrfs_device * next_device)2179 void __cold btrfs_assign_next_active_device(struct btrfs_device *device,
2180 struct btrfs_device *next_device)
2181 {
2182 struct btrfs_fs_info *fs_info = device->fs_info;
2183
2184 if (!next_device)
2185 next_device = btrfs_find_next_active_device(fs_info->fs_devices,
2186 device);
2187 ASSERT(next_device);
2188
2189 if (fs_info->sb->s_bdev &&
2190 (fs_info->sb->s_bdev == device->bdev))
2191 fs_info->sb->s_bdev = next_device->bdev;
2192
2193 if (fs_info->fs_devices->latest_dev->bdev == device->bdev)
2194 fs_info->fs_devices->latest_dev = next_device;
2195 }
2196
2197 /*
2198 * Return btrfs_fs_devices::num_devices excluding the device that's being
2199 * currently replaced.
2200 */
btrfs_num_devices(struct btrfs_fs_info * fs_info)2201 static u64 btrfs_num_devices(struct btrfs_fs_info *fs_info)
2202 {
2203 u64 num_devices = fs_info->fs_devices->num_devices;
2204
2205 down_read(&fs_info->dev_replace.rwsem);
2206 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
2207 ASSERT(num_devices > 1);
2208 num_devices--;
2209 }
2210 up_read(&fs_info->dev_replace.rwsem);
2211
2212 return num_devices;
2213 }
2214
btrfs_scratch_superblock(struct btrfs_fs_info * fs_info,struct block_device * bdev,int copy_num)2215 static void btrfs_scratch_superblock(struct btrfs_fs_info *fs_info,
2216 struct block_device *bdev, int copy_num)
2217 {
2218 struct btrfs_super_block *disk_super;
2219 const size_t len = sizeof(disk_super->magic);
2220 const u64 bytenr = btrfs_sb_offset(copy_num);
2221 int ret;
2222
2223 disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr);
2224 if (IS_ERR(disk_super))
2225 return;
2226
2227 memset(&disk_super->magic, 0, len);
2228 folio_mark_dirty(virt_to_folio(disk_super));
2229 btrfs_release_disk_super(disk_super);
2230
2231 ret = sync_blockdev_range(bdev, bytenr, bytenr + len - 1);
2232 if (ret)
2233 btrfs_warn(fs_info, "error clearing superblock number %d (%d)",
2234 copy_num, ret);
2235 }
2236
btrfs_scratch_superblocks(struct btrfs_fs_info * fs_info,struct btrfs_device * device)2237 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, struct btrfs_device *device)
2238 {
2239 int copy_num;
2240 struct block_device *bdev = device->bdev;
2241
2242 if (!bdev)
2243 return;
2244
2245 for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX; copy_num++) {
2246 if (bdev_is_zoned(bdev))
2247 btrfs_reset_sb_log_zones(bdev, copy_num);
2248 else
2249 btrfs_scratch_superblock(fs_info, bdev, copy_num);
2250 }
2251
2252 /* Notify udev that device has changed */
2253 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
2254
2255 /* Update ctime/mtime for device path for libblkid */
2256 update_dev_time(device->name->str);
2257 }
2258
btrfs_rm_device(struct btrfs_fs_info * fs_info,struct btrfs_dev_lookup_args * args,struct file ** bdev_file)2259 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
2260 struct btrfs_dev_lookup_args *args,
2261 struct file **bdev_file)
2262 {
2263 struct btrfs_trans_handle *trans;
2264 struct btrfs_device *device;
2265 struct btrfs_fs_devices *cur_devices;
2266 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2267 u64 num_devices;
2268 int ret = 0;
2269
2270 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
2271 btrfs_err(fs_info, "device remove not supported on extent tree v2 yet");
2272 return -EINVAL;
2273 }
2274
2275 /*
2276 * The device list in fs_devices is accessed without locks (neither
2277 * uuid_mutex nor device_list_mutex) as it won't change on a mounted
2278 * filesystem and another device rm cannot run.
2279 */
2280 num_devices = btrfs_num_devices(fs_info);
2281
2282 ret = btrfs_check_raid_min_devices(fs_info, num_devices - 1);
2283 if (ret)
2284 return ret;
2285
2286 device = btrfs_find_device(fs_info->fs_devices, args);
2287 if (!device) {
2288 if (args->missing)
2289 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
2290 else
2291 ret = -ENOENT;
2292 return ret;
2293 }
2294
2295 if (btrfs_pinned_by_swapfile(fs_info, device)) {
2296 btrfs_warn_in_rcu(fs_info,
2297 "cannot remove device %s (devid %llu) due to active swapfile",
2298 btrfs_dev_name(device), device->devid);
2299 return -ETXTBSY;
2300 }
2301
2302 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
2303 return BTRFS_ERROR_DEV_TGT_REPLACE;
2304
2305 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
2306 fs_info->fs_devices->rw_devices == 1)
2307 return BTRFS_ERROR_DEV_ONLY_WRITABLE;
2308
2309 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
2310 mutex_lock(&fs_info->chunk_mutex);
2311 list_del_init(&device->dev_alloc_list);
2312 device->fs_devices->rw_devices--;
2313 mutex_unlock(&fs_info->chunk_mutex);
2314 }
2315
2316 ret = btrfs_shrink_device(device, 0);
2317 if (ret)
2318 goto error_undo;
2319
2320 trans = btrfs_start_transaction(fs_info->chunk_root, 0);
2321 if (IS_ERR(trans)) {
2322 ret = PTR_ERR(trans);
2323 goto error_undo;
2324 }
2325
2326 ret = btrfs_rm_dev_item(trans, device);
2327 if (ret) {
2328 /* Any error in dev item removal is critical */
2329 btrfs_crit(fs_info,
2330 "failed to remove device item for devid %llu: %d",
2331 device->devid, ret);
2332 btrfs_abort_transaction(trans, ret);
2333 btrfs_end_transaction(trans);
2334 return ret;
2335 }
2336
2337 clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
2338 btrfs_scrub_cancel_dev(device);
2339
2340 /*
2341 * the device list mutex makes sure that we don't change
2342 * the device list while someone else is writing out all
2343 * the device supers. Whoever is writing all supers, should
2344 * lock the device list mutex before getting the number of
2345 * devices in the super block (super_copy). Conversely,
2346 * whoever updates the number of devices in the super block
2347 * (super_copy) should hold the device list mutex.
2348 */
2349
2350 /*
2351 * In normal cases the cur_devices == fs_devices. But in case
2352 * of deleting a seed device, the cur_devices should point to
2353 * its own fs_devices listed under the fs_devices->seed_list.
2354 */
2355 cur_devices = device->fs_devices;
2356 mutex_lock(&fs_devices->device_list_mutex);
2357 list_del_rcu(&device->dev_list);
2358
2359 cur_devices->num_devices--;
2360 cur_devices->total_devices--;
2361 /* Update total_devices of the parent fs_devices if it's seed */
2362 if (cur_devices != fs_devices)
2363 fs_devices->total_devices--;
2364
2365 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
2366 cur_devices->missing_devices--;
2367
2368 btrfs_assign_next_active_device(device, NULL);
2369
2370 if (device->bdev_file) {
2371 cur_devices->open_devices--;
2372 /* remove sysfs entry */
2373 btrfs_sysfs_remove_device(device);
2374 }
2375
2376 num_devices = btrfs_super_num_devices(fs_info->super_copy) - 1;
2377 btrfs_set_super_num_devices(fs_info->super_copy, num_devices);
2378 mutex_unlock(&fs_devices->device_list_mutex);
2379
2380 /*
2381 * At this point, the device is zero sized and detached from the
2382 * devices list. All that's left is to zero out the old supers and
2383 * free the device.
2384 *
2385 * We cannot call btrfs_close_bdev() here because we're holding the sb
2386 * write lock, and fput() on the block device will pull in the
2387 * ->open_mutex on the block device and it's dependencies. Instead
2388 * just flush the device and let the caller do the final bdev_release.
2389 */
2390 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
2391 btrfs_scratch_superblocks(fs_info, device);
2392 if (device->bdev) {
2393 sync_blockdev(device->bdev);
2394 invalidate_bdev(device->bdev);
2395 }
2396 }
2397
2398 *bdev_file = device->bdev_file;
2399 synchronize_rcu();
2400 btrfs_free_device(device);
2401
2402 /*
2403 * This can happen if cur_devices is the private seed devices list. We
2404 * cannot call close_fs_devices() here because it expects the uuid_mutex
2405 * to be held, but in fact we don't need that for the private
2406 * seed_devices, we can simply decrement cur_devices->opened and then
2407 * remove it from our list and free the fs_devices.
2408 */
2409 if (cur_devices->num_devices == 0) {
2410 list_del_init(&cur_devices->seed_list);
2411 ASSERT(cur_devices->opened == 1);
2412 cur_devices->opened--;
2413 free_fs_devices(cur_devices);
2414 }
2415
2416 ret = btrfs_commit_transaction(trans);
2417
2418 return ret;
2419
2420 error_undo:
2421 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
2422 mutex_lock(&fs_info->chunk_mutex);
2423 list_add(&device->dev_alloc_list,
2424 &fs_devices->alloc_list);
2425 device->fs_devices->rw_devices++;
2426 mutex_unlock(&fs_info->chunk_mutex);
2427 }
2428 return ret;
2429 }
2430
btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device * srcdev)2431 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev)
2432 {
2433 struct btrfs_fs_devices *fs_devices;
2434
2435 lockdep_assert_held(&srcdev->fs_info->fs_devices->device_list_mutex);
2436
2437 /*
2438 * in case of fs with no seed, srcdev->fs_devices will point
2439 * to fs_devices of fs_info. However when the dev being replaced is
2440 * a seed dev it will point to the seed's local fs_devices. In short
2441 * srcdev will have its correct fs_devices in both the cases.
2442 */
2443 fs_devices = srcdev->fs_devices;
2444
2445 list_del_rcu(&srcdev->dev_list);
2446 list_del(&srcdev->dev_alloc_list);
2447 fs_devices->num_devices--;
2448 if (test_bit(BTRFS_DEV_STATE_MISSING, &srcdev->dev_state))
2449 fs_devices->missing_devices--;
2450
2451 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state))
2452 fs_devices->rw_devices--;
2453
2454 if (srcdev->bdev)
2455 fs_devices->open_devices--;
2456 }
2457
btrfs_rm_dev_replace_free_srcdev(struct btrfs_device * srcdev)2458 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev)
2459 {
2460 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
2461
2462 mutex_lock(&uuid_mutex);
2463
2464 btrfs_close_bdev(srcdev);
2465 synchronize_rcu();
2466 btrfs_free_device(srcdev);
2467
2468 /* if this is no devs we rather delete the fs_devices */
2469 if (!fs_devices->num_devices) {
2470 /*
2471 * On a mounted FS, num_devices can't be zero unless it's a
2472 * seed. In case of a seed device being replaced, the replace
2473 * target added to the sprout FS, so there will be no more
2474 * device left under the seed FS.
2475 */
2476 ASSERT(fs_devices->seeding);
2477
2478 list_del_init(&fs_devices->seed_list);
2479 close_fs_devices(fs_devices);
2480 free_fs_devices(fs_devices);
2481 }
2482 mutex_unlock(&uuid_mutex);
2483 }
2484
btrfs_destroy_dev_replace_tgtdev(struct btrfs_device * tgtdev)2485 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev)
2486 {
2487 struct btrfs_fs_devices *fs_devices = tgtdev->fs_info->fs_devices;
2488
2489 mutex_lock(&fs_devices->device_list_mutex);
2490
2491 btrfs_sysfs_remove_device(tgtdev);
2492
2493 if (tgtdev->bdev)
2494 fs_devices->open_devices--;
2495
2496 fs_devices->num_devices--;
2497
2498 btrfs_assign_next_active_device(tgtdev, NULL);
2499
2500 list_del_rcu(&tgtdev->dev_list);
2501
2502 mutex_unlock(&fs_devices->device_list_mutex);
2503
2504 btrfs_scratch_superblocks(tgtdev->fs_info, tgtdev);
2505
2506 btrfs_close_bdev(tgtdev);
2507 synchronize_rcu();
2508 btrfs_free_device(tgtdev);
2509 }
2510
2511 /*
2512 * Populate args from device at path.
2513 *
2514 * @fs_info: the filesystem
2515 * @args: the args to populate
2516 * @path: the path to the device
2517 *
2518 * This will read the super block of the device at @path and populate @args with
2519 * the devid, fsid, and uuid. This is meant to be used for ioctls that need to
2520 * lookup a device to operate on, but need to do it before we take any locks.
2521 * This properly handles the special case of "missing" that a user may pass in,
2522 * and does some basic sanity checks. The caller must make sure that @path is
2523 * properly NUL terminated before calling in, and must call
2524 * btrfs_put_dev_args_from_path() in order to free up the temporary fsid and
2525 * uuid buffers.
2526 *
2527 * Return: 0 for success, -errno for failure
2528 */
btrfs_get_dev_args_from_path(struct btrfs_fs_info * fs_info,struct btrfs_dev_lookup_args * args,const char * path)2529 int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
2530 struct btrfs_dev_lookup_args *args,
2531 const char *path)
2532 {
2533 struct btrfs_super_block *disk_super;
2534 struct file *bdev_file;
2535 int ret;
2536
2537 if (!path || !path[0])
2538 return -EINVAL;
2539 if (!strcmp(path, "missing")) {
2540 args->missing = true;
2541 return 0;
2542 }
2543
2544 args->uuid = kzalloc(BTRFS_UUID_SIZE, GFP_KERNEL);
2545 args->fsid = kzalloc(BTRFS_FSID_SIZE, GFP_KERNEL);
2546 if (!args->uuid || !args->fsid) {
2547 btrfs_put_dev_args_from_path(args);
2548 return -ENOMEM;
2549 }
2550
2551 ret = btrfs_get_bdev_and_sb(path, BLK_OPEN_READ, NULL, 0,
2552 &bdev_file, &disk_super);
2553 if (ret) {
2554 btrfs_put_dev_args_from_path(args);
2555 return ret;
2556 }
2557
2558 args->devid = btrfs_stack_device_id(&disk_super->dev_item);
2559 memcpy(args->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE);
2560 if (btrfs_fs_incompat(fs_info, METADATA_UUID))
2561 memcpy(args->fsid, disk_super->metadata_uuid, BTRFS_FSID_SIZE);
2562 else
2563 memcpy(args->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
2564 btrfs_release_disk_super(disk_super);
2565 fput(bdev_file);
2566 return 0;
2567 }
2568
2569 /*
2570 * Only use this jointly with btrfs_get_dev_args_from_path() because we will
2571 * allocate our ->uuid and ->fsid pointers, everybody else uses local variables
2572 * that don't need to be freed.
2573 */
btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args * args)2574 void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args)
2575 {
2576 kfree(args->uuid);
2577 kfree(args->fsid);
2578 args->uuid = NULL;
2579 args->fsid = NULL;
2580 }
2581
btrfs_find_device_by_devspec(struct btrfs_fs_info * fs_info,u64 devid,const char * device_path)2582 struct btrfs_device *btrfs_find_device_by_devspec(
2583 struct btrfs_fs_info *fs_info, u64 devid,
2584 const char *device_path)
2585 {
2586 BTRFS_DEV_LOOKUP_ARGS(args);
2587 struct btrfs_device *device;
2588 int ret;
2589
2590 if (devid) {
2591 args.devid = devid;
2592 device = btrfs_find_device(fs_info->fs_devices, &args);
2593 if (!device)
2594 return ERR_PTR(-ENOENT);
2595 return device;
2596 }
2597
2598 ret = btrfs_get_dev_args_from_path(fs_info, &args, device_path);
2599 if (ret)
2600 return ERR_PTR(ret);
2601 device = btrfs_find_device(fs_info->fs_devices, &args);
2602 btrfs_put_dev_args_from_path(&args);
2603 if (!device)
2604 return ERR_PTR(-ENOENT);
2605 return device;
2606 }
2607
btrfs_init_sprout(struct btrfs_fs_info * fs_info)2608 static struct btrfs_fs_devices *btrfs_init_sprout(struct btrfs_fs_info *fs_info)
2609 {
2610 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2611 struct btrfs_fs_devices *old_devices;
2612 struct btrfs_fs_devices *seed_devices;
2613
2614 lockdep_assert_held(&uuid_mutex);
2615 if (!fs_devices->seeding)
2616 return ERR_PTR(-EINVAL);
2617
2618 /*
2619 * Private copy of the seed devices, anchored at
2620 * fs_info->fs_devices->seed_list
2621 */
2622 seed_devices = alloc_fs_devices(NULL);
2623 if (IS_ERR(seed_devices))
2624 return seed_devices;
2625
2626 /*
2627 * It's necessary to retain a copy of the original seed fs_devices in
2628 * fs_uuids so that filesystems which have been seeded can successfully
2629 * reference the seed device from open_seed_devices. This also supports
2630 * multiple fs seed.
2631 */
2632 old_devices = clone_fs_devices(fs_devices);
2633 if (IS_ERR(old_devices)) {
2634 kfree(seed_devices);
2635 return old_devices;
2636 }
2637
2638 list_add(&old_devices->fs_list, &fs_uuids);
2639
2640 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
2641 seed_devices->opened = 1;
2642 INIT_LIST_HEAD(&seed_devices->devices);
2643 INIT_LIST_HEAD(&seed_devices->alloc_list);
2644 mutex_init(&seed_devices->device_list_mutex);
2645
2646 return seed_devices;
2647 }
2648
2649 /*
2650 * Splice seed devices into the sprout fs_devices.
2651 * Generate a new fsid for the sprouted read-write filesystem.
2652 */
btrfs_setup_sprout(struct btrfs_fs_info * fs_info,struct btrfs_fs_devices * seed_devices)2653 static void btrfs_setup_sprout(struct btrfs_fs_info *fs_info,
2654 struct btrfs_fs_devices *seed_devices)
2655 {
2656 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2657 struct btrfs_super_block *disk_super = fs_info->super_copy;
2658 struct btrfs_device *device;
2659 u64 super_flags;
2660
2661 /*
2662 * We are updating the fsid, the thread leading to device_list_add()
2663 * could race, so uuid_mutex is needed.
2664 */
2665 lockdep_assert_held(&uuid_mutex);
2666
2667 /*
2668 * The threads listed below may traverse dev_list but can do that without
2669 * device_list_mutex:
2670 * - All device ops and balance - as we are in btrfs_exclop_start.
2671 * - Various dev_list readers - are using RCU.
2672 * - btrfs_ioctl_fitrim() - is using RCU.
2673 *
2674 * For-read threads as below are using device_list_mutex:
2675 * - Readonly scrub btrfs_scrub_dev()
2676 * - Readonly scrub btrfs_scrub_progress()
2677 * - btrfs_get_dev_stats()
2678 */
2679 lockdep_assert_held(&fs_devices->device_list_mutex);
2680
2681 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
2682 synchronize_rcu);
2683 list_for_each_entry(device, &seed_devices->devices, dev_list)
2684 device->fs_devices = seed_devices;
2685
2686 fs_devices->seeding = false;
2687 fs_devices->num_devices = 0;
2688 fs_devices->open_devices = 0;
2689 fs_devices->missing_devices = 0;
2690 fs_devices->rotating = false;
2691 list_add(&seed_devices->seed_list, &fs_devices->seed_list);
2692
2693 generate_random_uuid(fs_devices->fsid);
2694 memcpy(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE);
2695 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2696
2697 super_flags = btrfs_super_flags(disk_super) &
2698 ~BTRFS_SUPER_FLAG_SEEDING;
2699 btrfs_set_super_flags(disk_super, super_flags);
2700 }
2701
2702 /*
2703 * Store the expected generation for seed devices in device items.
2704 */
btrfs_finish_sprout(struct btrfs_trans_handle * trans)2705 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
2706 {
2707 BTRFS_DEV_LOOKUP_ARGS(args);
2708 struct btrfs_fs_info *fs_info = trans->fs_info;
2709 struct btrfs_root *root = fs_info->chunk_root;
2710 struct btrfs_path *path;
2711 struct extent_buffer *leaf;
2712 struct btrfs_dev_item *dev_item;
2713 struct btrfs_device *device;
2714 struct btrfs_key key;
2715 u8 fs_uuid[BTRFS_FSID_SIZE];
2716 u8 dev_uuid[BTRFS_UUID_SIZE];
2717 int ret;
2718
2719 path = btrfs_alloc_path();
2720 if (!path)
2721 return -ENOMEM;
2722
2723 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2724 key.offset = 0;
2725 key.type = BTRFS_DEV_ITEM_KEY;
2726
2727 while (1) {
2728 btrfs_reserve_chunk_metadata(trans, false);
2729 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2730 btrfs_trans_release_chunk_metadata(trans);
2731 if (ret < 0)
2732 goto error;
2733
2734 leaf = path->nodes[0];
2735 next_slot:
2736 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2737 ret = btrfs_next_leaf(root, path);
2738 if (ret > 0)
2739 break;
2740 if (ret < 0)
2741 goto error;
2742 leaf = path->nodes[0];
2743 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2744 btrfs_release_path(path);
2745 continue;
2746 }
2747
2748 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2749 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2750 key.type != BTRFS_DEV_ITEM_KEY)
2751 break;
2752
2753 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2754 struct btrfs_dev_item);
2755 args.devid = btrfs_device_id(leaf, dev_item);
2756 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2757 BTRFS_UUID_SIZE);
2758 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2759 BTRFS_FSID_SIZE);
2760 args.uuid = dev_uuid;
2761 args.fsid = fs_uuid;
2762 device = btrfs_find_device(fs_info->fs_devices, &args);
2763 BUG_ON(!device); /* Logic error */
2764
2765 if (device->fs_devices->seeding)
2766 btrfs_set_device_generation(leaf, dev_item,
2767 device->generation);
2768
2769 path->slots[0]++;
2770 goto next_slot;
2771 }
2772 ret = 0;
2773 error:
2774 btrfs_free_path(path);
2775 return ret;
2776 }
2777
btrfs_init_new_device(struct btrfs_fs_info * fs_info,const char * device_path)2778 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path)
2779 {
2780 struct btrfs_root *root = fs_info->dev_root;
2781 struct btrfs_trans_handle *trans;
2782 struct btrfs_device *device;
2783 struct file *bdev_file;
2784 struct super_block *sb = fs_info->sb;
2785 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2786 struct btrfs_fs_devices *seed_devices = NULL;
2787 u64 orig_super_total_bytes;
2788 u64 orig_super_num_devices;
2789 int ret = 0;
2790 bool seeding_dev = false;
2791 bool locked = false;
2792
2793 if (sb_rdonly(sb) && !fs_devices->seeding)
2794 return -EROFS;
2795
2796 bdev_file = bdev_file_open_by_path(device_path, BLK_OPEN_WRITE,
2797 fs_info->bdev_holder, NULL);
2798 if (IS_ERR(bdev_file))
2799 return PTR_ERR(bdev_file);
2800
2801 if (!btrfs_check_device_zone_type(fs_info, file_bdev(bdev_file))) {
2802 ret = -EINVAL;
2803 goto error;
2804 }
2805
2806 if (fs_devices->seeding) {
2807 seeding_dev = true;
2808 down_write(&sb->s_umount);
2809 mutex_lock(&uuid_mutex);
2810 locked = true;
2811 }
2812
2813 sync_blockdev(file_bdev(bdev_file));
2814
2815 rcu_read_lock();
2816 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
2817 if (device->bdev == file_bdev(bdev_file)) {
2818 ret = -EEXIST;
2819 rcu_read_unlock();
2820 goto error;
2821 }
2822 }
2823 rcu_read_unlock();
2824
2825 device = btrfs_alloc_device(fs_info, NULL, NULL, device_path);
2826 if (IS_ERR(device)) {
2827 /* we can safely leave the fs_devices entry around */
2828 ret = PTR_ERR(device);
2829 goto error;
2830 }
2831
2832 device->fs_info = fs_info;
2833 device->bdev_file = bdev_file;
2834 device->bdev = file_bdev(bdev_file);
2835 ret = lookup_bdev(device_path, &device->devt);
2836 if (ret)
2837 goto error_free_device;
2838
2839 ret = btrfs_get_dev_zone_info(device, false);
2840 if (ret)
2841 goto error_free_device;
2842
2843 trans = btrfs_start_transaction(root, 0);
2844 if (IS_ERR(trans)) {
2845 ret = PTR_ERR(trans);
2846 goto error_free_zone;
2847 }
2848
2849 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
2850 device->generation = trans->transid;
2851 device->io_width = fs_info->sectorsize;
2852 device->io_align = fs_info->sectorsize;
2853 device->sector_size = fs_info->sectorsize;
2854 device->total_bytes =
2855 round_down(bdev_nr_bytes(device->bdev), fs_info->sectorsize);
2856 device->disk_total_bytes = device->total_bytes;
2857 device->commit_total_bytes = device->total_bytes;
2858 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
2859 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
2860 device->dev_stats_valid = 1;
2861 set_blocksize(device->bdev_file, BTRFS_BDEV_BLOCKSIZE);
2862
2863 if (seeding_dev) {
2864 /* GFP_KERNEL allocation must not be under device_list_mutex */
2865 seed_devices = btrfs_init_sprout(fs_info);
2866 if (IS_ERR(seed_devices)) {
2867 ret = PTR_ERR(seed_devices);
2868 btrfs_abort_transaction(trans, ret);
2869 goto error_trans;
2870 }
2871 }
2872
2873 mutex_lock(&fs_devices->device_list_mutex);
2874 if (seeding_dev) {
2875 btrfs_setup_sprout(fs_info, seed_devices);
2876 btrfs_assign_next_active_device(fs_info->fs_devices->latest_dev,
2877 device);
2878 }
2879
2880 device->fs_devices = fs_devices;
2881
2882 mutex_lock(&fs_info->chunk_mutex);
2883 list_add_rcu(&device->dev_list, &fs_devices->devices);
2884 list_add(&device->dev_alloc_list, &fs_devices->alloc_list);
2885 fs_devices->num_devices++;
2886 fs_devices->open_devices++;
2887 fs_devices->rw_devices++;
2888 fs_devices->total_devices++;
2889 fs_devices->total_rw_bytes += device->total_bytes;
2890
2891 atomic64_add(device->total_bytes, &fs_info->free_chunk_space);
2892
2893 if (!bdev_nonrot(device->bdev))
2894 fs_devices->rotating = true;
2895
2896 orig_super_total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
2897 btrfs_set_super_total_bytes(fs_info->super_copy,
2898 round_down(orig_super_total_bytes + device->total_bytes,
2899 fs_info->sectorsize));
2900
2901 orig_super_num_devices = btrfs_super_num_devices(fs_info->super_copy);
2902 btrfs_set_super_num_devices(fs_info->super_copy,
2903 orig_super_num_devices + 1);
2904
2905 /*
2906 * we've got more storage, clear any full flags on the space
2907 * infos
2908 */
2909 btrfs_clear_space_info_full(fs_info);
2910
2911 mutex_unlock(&fs_info->chunk_mutex);
2912
2913 /* Add sysfs device entry */
2914 btrfs_sysfs_add_device(device);
2915
2916 mutex_unlock(&fs_devices->device_list_mutex);
2917
2918 if (seeding_dev) {
2919 mutex_lock(&fs_info->chunk_mutex);
2920 ret = init_first_rw_device(trans);
2921 mutex_unlock(&fs_info->chunk_mutex);
2922 if (ret) {
2923 btrfs_abort_transaction(trans, ret);
2924 goto error_sysfs;
2925 }
2926 }
2927
2928 ret = btrfs_add_dev_item(trans, device);
2929 if (ret) {
2930 btrfs_abort_transaction(trans, ret);
2931 goto error_sysfs;
2932 }
2933
2934 if (seeding_dev) {
2935 ret = btrfs_finish_sprout(trans);
2936 if (ret) {
2937 btrfs_abort_transaction(trans, ret);
2938 goto error_sysfs;
2939 }
2940
2941 /*
2942 * fs_devices now represents the newly sprouted filesystem and
2943 * its fsid has been changed by btrfs_sprout_splice().
2944 */
2945 btrfs_sysfs_update_sprout_fsid(fs_devices);
2946 }
2947
2948 ret = btrfs_commit_transaction(trans);
2949
2950 if (seeding_dev) {
2951 mutex_unlock(&uuid_mutex);
2952 up_write(&sb->s_umount);
2953 locked = false;
2954
2955 if (ret) /* transaction commit */
2956 return ret;
2957
2958 ret = btrfs_relocate_sys_chunks(fs_info);
2959 if (ret < 0)
2960 btrfs_handle_fs_error(fs_info, ret,
2961 "Failed to relocate sys chunks after device initialization. This can be fixed using the \"btrfs balance\" command.");
2962 trans = btrfs_attach_transaction(root);
2963 if (IS_ERR(trans)) {
2964 if (PTR_ERR(trans) == -ENOENT)
2965 return 0;
2966 ret = PTR_ERR(trans);
2967 trans = NULL;
2968 goto error_sysfs;
2969 }
2970 ret = btrfs_commit_transaction(trans);
2971 }
2972
2973 /*
2974 * Now that we have written a new super block to this device, check all
2975 * other fs_devices list if device_path alienates any other scanned
2976 * device.
2977 * We can ignore the return value as it typically returns -EINVAL and
2978 * only succeeds if the device was an alien.
2979 */
2980 btrfs_forget_devices(device->devt);
2981
2982 /* Update ctime/mtime for blkid or udev */
2983 update_dev_time(device_path);
2984
2985 return ret;
2986
2987 error_sysfs:
2988 btrfs_sysfs_remove_device(device);
2989 mutex_lock(&fs_info->fs_devices->device_list_mutex);
2990 mutex_lock(&fs_info->chunk_mutex);
2991 list_del_rcu(&device->dev_list);
2992 list_del(&device->dev_alloc_list);
2993 fs_info->fs_devices->num_devices--;
2994 fs_info->fs_devices->open_devices--;
2995 fs_info->fs_devices->rw_devices--;
2996 fs_info->fs_devices->total_devices--;
2997 fs_info->fs_devices->total_rw_bytes -= device->total_bytes;
2998 atomic64_sub(device->total_bytes, &fs_info->free_chunk_space);
2999 btrfs_set_super_total_bytes(fs_info->super_copy,
3000 orig_super_total_bytes);
3001 btrfs_set_super_num_devices(fs_info->super_copy,
3002 orig_super_num_devices);
3003 mutex_unlock(&fs_info->chunk_mutex);
3004 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3005 error_trans:
3006 if (trans)
3007 btrfs_end_transaction(trans);
3008 error_free_zone:
3009 btrfs_destroy_dev_zone_info(device);
3010 error_free_device:
3011 btrfs_free_device(device);
3012 error:
3013 fput(bdev_file);
3014 if (locked) {
3015 mutex_unlock(&uuid_mutex);
3016 up_write(&sb->s_umount);
3017 }
3018 return ret;
3019 }
3020
btrfs_update_device(struct btrfs_trans_handle * trans,struct btrfs_device * device)3021 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
3022 struct btrfs_device *device)
3023 {
3024 int ret;
3025 struct btrfs_path *path;
3026 struct btrfs_root *root = device->fs_info->chunk_root;
3027 struct btrfs_dev_item *dev_item;
3028 struct extent_buffer *leaf;
3029 struct btrfs_key key;
3030
3031 path = btrfs_alloc_path();
3032 if (!path)
3033 return -ENOMEM;
3034
3035 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
3036 key.type = BTRFS_DEV_ITEM_KEY;
3037 key.offset = device->devid;
3038
3039 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
3040 if (ret < 0)
3041 goto out;
3042
3043 if (ret > 0) {
3044 ret = -ENOENT;
3045 goto out;
3046 }
3047
3048 leaf = path->nodes[0];
3049 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
3050
3051 btrfs_set_device_id(leaf, dev_item, device->devid);
3052 btrfs_set_device_type(leaf, dev_item, device->type);
3053 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
3054 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
3055 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
3056 btrfs_set_device_total_bytes(leaf, dev_item,
3057 btrfs_device_get_disk_total_bytes(device));
3058 btrfs_set_device_bytes_used(leaf, dev_item,
3059 btrfs_device_get_bytes_used(device));
3060 out:
3061 btrfs_free_path(path);
3062 return ret;
3063 }
3064
btrfs_grow_device(struct btrfs_trans_handle * trans,struct btrfs_device * device,u64 new_size)3065 int btrfs_grow_device(struct btrfs_trans_handle *trans,
3066 struct btrfs_device *device, u64 new_size)
3067 {
3068 struct btrfs_fs_info *fs_info = device->fs_info;
3069 struct btrfs_super_block *super_copy = fs_info->super_copy;
3070 u64 old_total;
3071 u64 diff;
3072 int ret;
3073
3074 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
3075 return -EACCES;
3076
3077 new_size = round_down(new_size, fs_info->sectorsize);
3078
3079 mutex_lock(&fs_info->chunk_mutex);
3080 old_total = btrfs_super_total_bytes(super_copy);
3081 diff = round_down(new_size - device->total_bytes, fs_info->sectorsize);
3082
3083 if (new_size <= device->total_bytes ||
3084 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
3085 mutex_unlock(&fs_info->chunk_mutex);
3086 return -EINVAL;
3087 }
3088
3089 btrfs_set_super_total_bytes(super_copy,
3090 round_down(old_total + diff, fs_info->sectorsize));
3091 device->fs_devices->total_rw_bytes += diff;
3092 atomic64_add(diff, &fs_info->free_chunk_space);
3093
3094 btrfs_device_set_total_bytes(device, new_size);
3095 btrfs_device_set_disk_total_bytes(device, new_size);
3096 btrfs_clear_space_info_full(device->fs_info);
3097 if (list_empty(&device->post_commit_list))
3098 list_add_tail(&device->post_commit_list,
3099 &trans->transaction->dev_update_list);
3100 mutex_unlock(&fs_info->chunk_mutex);
3101
3102 btrfs_reserve_chunk_metadata(trans, false);
3103 ret = btrfs_update_device(trans, device);
3104 btrfs_trans_release_chunk_metadata(trans);
3105
3106 return ret;
3107 }
3108
btrfs_free_chunk(struct btrfs_trans_handle * trans,u64 chunk_offset)3109 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
3110 {
3111 struct btrfs_fs_info *fs_info = trans->fs_info;
3112 struct btrfs_root *root = fs_info->chunk_root;
3113 int ret;
3114 struct btrfs_path *path;
3115 struct btrfs_key key;
3116
3117 path = btrfs_alloc_path();
3118 if (!path)
3119 return -ENOMEM;
3120
3121 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3122 key.offset = chunk_offset;
3123 key.type = BTRFS_CHUNK_ITEM_KEY;
3124
3125 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3126 if (ret < 0)
3127 goto out;
3128 else if (ret > 0) { /* Logic error or corruption */
3129 btrfs_err(fs_info, "failed to lookup chunk %llu when freeing",
3130 chunk_offset);
3131 btrfs_abort_transaction(trans, -ENOENT);
3132 ret = -EUCLEAN;
3133 goto out;
3134 }
3135
3136 ret = btrfs_del_item(trans, root, path);
3137 if (ret < 0) {
3138 btrfs_err(fs_info, "failed to delete chunk %llu item", chunk_offset);
3139 btrfs_abort_transaction(trans, ret);
3140 goto out;
3141 }
3142 out:
3143 btrfs_free_path(path);
3144 return ret;
3145 }
3146
btrfs_del_sys_chunk(struct btrfs_fs_info * fs_info,u64 chunk_offset)3147 static int btrfs_del_sys_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
3148 {
3149 struct btrfs_super_block *super_copy = fs_info->super_copy;
3150 struct btrfs_disk_key *disk_key;
3151 struct btrfs_chunk *chunk;
3152 u8 *ptr;
3153 int ret = 0;
3154 u32 num_stripes;
3155 u32 array_size;
3156 u32 len = 0;
3157 u32 cur;
3158 struct btrfs_key key;
3159
3160 lockdep_assert_held(&fs_info->chunk_mutex);
3161 array_size = btrfs_super_sys_array_size(super_copy);
3162
3163 ptr = super_copy->sys_chunk_array;
3164 cur = 0;
3165
3166 while (cur < array_size) {
3167 disk_key = (struct btrfs_disk_key *)ptr;
3168 btrfs_disk_key_to_cpu(&key, disk_key);
3169
3170 len = sizeof(*disk_key);
3171
3172 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
3173 chunk = (struct btrfs_chunk *)(ptr + len);
3174 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
3175 len += btrfs_chunk_item_size(num_stripes);
3176 } else {
3177 ret = -EIO;
3178 break;
3179 }
3180 if (key.objectid == BTRFS_FIRST_CHUNK_TREE_OBJECTID &&
3181 key.offset == chunk_offset) {
3182 memmove(ptr, ptr + len, array_size - (cur + len));
3183 array_size -= len;
3184 btrfs_set_super_sys_array_size(super_copy, array_size);
3185 } else {
3186 ptr += len;
3187 cur += len;
3188 }
3189 }
3190 return ret;
3191 }
3192
btrfs_find_chunk_map_nolock(struct btrfs_fs_info * fs_info,u64 logical,u64 length)3193 struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info,
3194 u64 logical, u64 length)
3195 {
3196 struct rb_node *node = fs_info->mapping_tree.rb_root.rb_node;
3197 struct rb_node *prev = NULL;
3198 struct rb_node *orig_prev;
3199 struct btrfs_chunk_map *map;
3200 struct btrfs_chunk_map *prev_map = NULL;
3201
3202 while (node) {
3203 map = rb_entry(node, struct btrfs_chunk_map, rb_node);
3204 prev = node;
3205 prev_map = map;
3206
3207 if (logical < map->start) {
3208 node = node->rb_left;
3209 } else if (logical >= map->start + map->chunk_len) {
3210 node = node->rb_right;
3211 } else {
3212 refcount_inc(&map->refs);
3213 return map;
3214 }
3215 }
3216
3217 if (!prev)
3218 return NULL;
3219
3220 orig_prev = prev;
3221 while (prev && logical >= prev_map->start + prev_map->chunk_len) {
3222 prev = rb_next(prev);
3223 prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
3224 }
3225
3226 if (!prev) {
3227 prev = orig_prev;
3228 prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
3229 while (prev && logical < prev_map->start) {
3230 prev = rb_prev(prev);
3231 prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
3232 }
3233 }
3234
3235 if (prev) {
3236 u64 end = logical + length;
3237
3238 /*
3239 * Caller can pass a U64_MAX length when it wants to get any
3240 * chunk starting at an offset of 'logical' or higher, so deal
3241 * with underflow by resetting the end offset to U64_MAX.
3242 */
3243 if (end < logical)
3244 end = U64_MAX;
3245
3246 if (end > prev_map->start &&
3247 logical < prev_map->start + prev_map->chunk_len) {
3248 refcount_inc(&prev_map->refs);
3249 return prev_map;
3250 }
3251 }
3252
3253 return NULL;
3254 }
3255
btrfs_find_chunk_map(struct btrfs_fs_info * fs_info,u64 logical,u64 length)3256 struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info,
3257 u64 logical, u64 length)
3258 {
3259 struct btrfs_chunk_map *map;
3260
3261 read_lock(&fs_info->mapping_tree_lock);
3262 map = btrfs_find_chunk_map_nolock(fs_info, logical, length);
3263 read_unlock(&fs_info->mapping_tree_lock);
3264
3265 return map;
3266 }
3267
3268 /*
3269 * Find the mapping containing the given logical extent.
3270 *
3271 * @logical: Logical block offset in bytes.
3272 * @length: Length of extent in bytes.
3273 *
3274 * Return: Chunk mapping or ERR_PTR.
3275 */
btrfs_get_chunk_map(struct btrfs_fs_info * fs_info,u64 logical,u64 length)3276 struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
3277 u64 logical, u64 length)
3278 {
3279 struct btrfs_chunk_map *map;
3280
3281 map = btrfs_find_chunk_map(fs_info, logical, length);
3282
3283 if (unlikely(!map)) {
3284 btrfs_crit(fs_info,
3285 "unable to find chunk map for logical %llu length %llu",
3286 logical, length);
3287 return ERR_PTR(-EINVAL);
3288 }
3289
3290 if (unlikely(map->start > logical || map->start + map->chunk_len <= logical)) {
3291 btrfs_crit(fs_info,
3292 "found a bad chunk map, wanted %llu-%llu, found %llu-%llu",
3293 logical, logical + length, map->start,
3294 map->start + map->chunk_len);
3295 btrfs_free_chunk_map(map);
3296 return ERR_PTR(-EINVAL);
3297 }
3298
3299 /* Callers are responsible for dropping the reference. */
3300 return map;
3301 }
3302
remove_chunk_item(struct btrfs_trans_handle * trans,struct btrfs_chunk_map * map,u64 chunk_offset)3303 static int remove_chunk_item(struct btrfs_trans_handle *trans,
3304 struct btrfs_chunk_map *map, u64 chunk_offset)
3305 {
3306 int i;
3307
3308 /*
3309 * Removing chunk items and updating the device items in the chunks btree
3310 * requires holding the chunk_mutex.
3311 * See the comment at btrfs_chunk_alloc() for the details.
3312 */
3313 lockdep_assert_held(&trans->fs_info->chunk_mutex);
3314
3315 for (i = 0; i < map->num_stripes; i++) {
3316 int ret;
3317
3318 ret = btrfs_update_device(trans, map->stripes[i].dev);
3319 if (ret)
3320 return ret;
3321 }
3322
3323 return btrfs_free_chunk(trans, chunk_offset);
3324 }
3325
btrfs_remove_chunk(struct btrfs_trans_handle * trans,u64 chunk_offset)3326 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
3327 {
3328 struct btrfs_fs_info *fs_info = trans->fs_info;
3329 struct btrfs_chunk_map *map;
3330 u64 dev_extent_len = 0;
3331 int i, ret = 0;
3332 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3333
3334 map = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
3335 if (IS_ERR(map)) {
3336 /*
3337 * This is a logic error, but we don't want to just rely on the
3338 * user having built with ASSERT enabled, so if ASSERT doesn't
3339 * do anything we still error out.
3340 */
3341 ASSERT(0);
3342 return PTR_ERR(map);
3343 }
3344
3345 /*
3346 * First delete the device extent items from the devices btree.
3347 * We take the device_list_mutex to avoid racing with the finishing phase
3348 * of a device replace operation. See the comment below before acquiring
3349 * fs_info->chunk_mutex. Note that here we do not acquire the chunk_mutex
3350 * because that can result in a deadlock when deleting the device extent
3351 * items from the devices btree - COWing an extent buffer from the btree
3352 * may result in allocating a new metadata chunk, which would attempt to
3353 * lock again fs_info->chunk_mutex.
3354 */
3355 mutex_lock(&fs_devices->device_list_mutex);
3356 for (i = 0; i < map->num_stripes; i++) {
3357 struct btrfs_device *device = map->stripes[i].dev;
3358 ret = btrfs_free_dev_extent(trans, device,
3359 map->stripes[i].physical,
3360 &dev_extent_len);
3361 if (ret) {
3362 mutex_unlock(&fs_devices->device_list_mutex);
3363 btrfs_abort_transaction(trans, ret);
3364 goto out;
3365 }
3366
3367 if (device->bytes_used > 0) {
3368 mutex_lock(&fs_info->chunk_mutex);
3369 btrfs_device_set_bytes_used(device,
3370 device->bytes_used - dev_extent_len);
3371 atomic64_add(dev_extent_len, &fs_info->free_chunk_space);
3372 btrfs_clear_space_info_full(fs_info);
3373 mutex_unlock(&fs_info->chunk_mutex);
3374 }
3375 }
3376 mutex_unlock(&fs_devices->device_list_mutex);
3377
3378 /*
3379 * We acquire fs_info->chunk_mutex for 2 reasons:
3380 *
3381 * 1) Just like with the first phase of the chunk allocation, we must
3382 * reserve system space, do all chunk btree updates and deletions, and
3383 * update the system chunk array in the superblock while holding this
3384 * mutex. This is for similar reasons as explained on the comment at
3385 * the top of btrfs_chunk_alloc();
3386 *
3387 * 2) Prevent races with the final phase of a device replace operation
3388 * that replaces the device object associated with the map's stripes,
3389 * because the device object's id can change at any time during that
3390 * final phase of the device replace operation
3391 * (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the
3392 * replaced device and then see it with an ID of
3393 * BTRFS_DEV_REPLACE_DEVID, which would cause a failure when updating
3394 * the device item, which does not exists on the chunk btree.
3395 * The finishing phase of device replace acquires both the
3396 * device_list_mutex and the chunk_mutex, in that order, so we are
3397 * safe by just acquiring the chunk_mutex.
3398 */
3399 trans->removing_chunk = true;
3400 mutex_lock(&fs_info->chunk_mutex);
3401
3402 check_system_chunk(trans, map->type);
3403
3404 ret = remove_chunk_item(trans, map, chunk_offset);
3405 /*
3406 * Normally we should not get -ENOSPC since we reserved space before
3407 * through the call to check_system_chunk().
3408 *
3409 * Despite our system space_info having enough free space, we may not
3410 * be able to allocate extents from its block groups, because all have
3411 * an incompatible profile, which will force us to allocate a new system
3412 * block group with the right profile, or right after we called
3413 * check_system_space() above, a scrub turned the only system block group
3414 * with enough free space into RO mode.
3415 * This is explained with more detail at do_chunk_alloc().
3416 *
3417 * So if we get -ENOSPC, allocate a new system chunk and retry once.
3418 */
3419 if (ret == -ENOSPC) {
3420 const u64 sys_flags = btrfs_system_alloc_profile(fs_info);
3421 struct btrfs_block_group *sys_bg;
3422
3423 sys_bg = btrfs_create_chunk(trans, sys_flags);
3424 if (IS_ERR(sys_bg)) {
3425 ret = PTR_ERR(sys_bg);
3426 btrfs_abort_transaction(trans, ret);
3427 goto out;
3428 }
3429
3430 ret = btrfs_chunk_alloc_add_chunk_item(trans, sys_bg);
3431 if (ret) {
3432 btrfs_abort_transaction(trans, ret);
3433 goto out;
3434 }
3435
3436 ret = remove_chunk_item(trans, map, chunk_offset);
3437 if (ret) {
3438 btrfs_abort_transaction(trans, ret);
3439 goto out;
3440 }
3441 } else if (ret) {
3442 btrfs_abort_transaction(trans, ret);
3443 goto out;
3444 }
3445
3446 trace_btrfs_chunk_free(fs_info, map, chunk_offset, map->chunk_len);
3447
3448 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
3449 ret = btrfs_del_sys_chunk(fs_info, chunk_offset);
3450 if (ret) {
3451 btrfs_abort_transaction(trans, ret);
3452 goto out;
3453 }
3454 }
3455
3456 mutex_unlock(&fs_info->chunk_mutex);
3457 trans->removing_chunk = false;
3458
3459 /*
3460 * We are done with chunk btree updates and deletions, so release the
3461 * system space we previously reserved (with check_system_chunk()).
3462 */
3463 btrfs_trans_release_chunk_metadata(trans);
3464
3465 ret = btrfs_remove_block_group(trans, map);
3466 if (ret) {
3467 btrfs_abort_transaction(trans, ret);
3468 goto out;
3469 }
3470
3471 out:
3472 if (trans->removing_chunk) {
3473 mutex_unlock(&fs_info->chunk_mutex);
3474 trans->removing_chunk = false;
3475 }
3476 /* once for us */
3477 btrfs_free_chunk_map(map);
3478 return ret;
3479 }
3480
btrfs_relocate_chunk(struct btrfs_fs_info * fs_info,u64 chunk_offset)3481 int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
3482 {
3483 struct btrfs_root *root = fs_info->chunk_root;
3484 struct btrfs_trans_handle *trans;
3485 struct btrfs_block_group *block_group;
3486 u64 length;
3487 int ret;
3488
3489 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
3490 btrfs_err(fs_info,
3491 "relocate: not supported on extent tree v2 yet");
3492 return -EINVAL;
3493 }
3494
3495 /*
3496 * Prevent races with automatic removal of unused block groups.
3497 * After we relocate and before we remove the chunk with offset
3498 * chunk_offset, automatic removal of the block group can kick in,
3499 * resulting in a failure when calling btrfs_remove_chunk() below.
3500 *
3501 * Make sure to acquire this mutex before doing a tree search (dev
3502 * or chunk trees) to find chunks. Otherwise the cleaner kthread might
3503 * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after
3504 * we release the path used to search the chunk/dev tree and before
3505 * the current task acquires this mutex and calls us.
3506 */
3507 lockdep_assert_held(&fs_info->reclaim_bgs_lock);
3508
3509 /* step one, relocate all the extents inside this chunk */
3510 btrfs_scrub_pause(fs_info);
3511 ret = btrfs_relocate_block_group(fs_info, chunk_offset);
3512 btrfs_scrub_continue(fs_info);
3513 if (ret) {
3514 /*
3515 * If we had a transaction abort, stop all running scrubs.
3516 * See transaction.c:cleanup_transaction() why we do it here.
3517 */
3518 if (BTRFS_FS_ERROR(fs_info))
3519 btrfs_scrub_cancel(fs_info);
3520 return ret;
3521 }
3522
3523 block_group = btrfs_lookup_block_group(fs_info, chunk_offset);
3524 if (!block_group)
3525 return -ENOENT;
3526 btrfs_discard_cancel_work(&fs_info->discard_ctl, block_group);
3527 length = block_group->length;
3528 btrfs_put_block_group(block_group);
3529
3530 /*
3531 * On a zoned file system, discard the whole block group, this will
3532 * trigger a REQ_OP_ZONE_RESET operation on the device zone. If
3533 * resetting the zone fails, don't treat it as a fatal problem from the
3534 * filesystem's point of view.
3535 */
3536 if (btrfs_is_zoned(fs_info)) {
3537 ret = btrfs_discard_extent(fs_info, chunk_offset, length, NULL);
3538 if (ret)
3539 btrfs_info(fs_info,
3540 "failed to reset zone %llu after relocation",
3541 chunk_offset);
3542 }
3543
3544 trans = btrfs_start_trans_remove_block_group(root->fs_info,
3545 chunk_offset);
3546 if (IS_ERR(trans)) {
3547 ret = PTR_ERR(trans);
3548 btrfs_handle_fs_error(root->fs_info, ret, NULL);
3549 return ret;
3550 }
3551
3552 /*
3553 * step two, delete the device extents and the
3554 * chunk tree entries
3555 */
3556 ret = btrfs_remove_chunk(trans, chunk_offset);
3557 btrfs_end_transaction(trans);
3558 return ret;
3559 }
3560
btrfs_relocate_sys_chunks(struct btrfs_fs_info * fs_info)3561 static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info)
3562 {
3563 struct btrfs_root *chunk_root = fs_info->chunk_root;
3564 struct btrfs_path *path;
3565 struct extent_buffer *leaf;
3566 struct btrfs_chunk *chunk;
3567 struct btrfs_key key;
3568 struct btrfs_key found_key;
3569 u64 chunk_type;
3570 bool retried = false;
3571 int failed = 0;
3572 int ret;
3573
3574 path = btrfs_alloc_path();
3575 if (!path)
3576 return -ENOMEM;
3577
3578 again:
3579 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3580 key.offset = (u64)-1;
3581 key.type = BTRFS_CHUNK_ITEM_KEY;
3582
3583 while (1) {
3584 mutex_lock(&fs_info->reclaim_bgs_lock);
3585 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3586 if (ret < 0) {
3587 mutex_unlock(&fs_info->reclaim_bgs_lock);
3588 goto error;
3589 }
3590 if (ret == 0) {
3591 /*
3592 * On the first search we would find chunk tree with
3593 * offset -1, which is not possible. On subsequent
3594 * loops this would find an existing item on an invalid
3595 * offset (one less than the previous one, wrong
3596 * alignment and size).
3597 */
3598 ret = -EUCLEAN;
3599 mutex_unlock(&fs_info->reclaim_bgs_lock);
3600 goto error;
3601 }
3602
3603 ret = btrfs_previous_item(chunk_root, path, key.objectid,
3604 key.type);
3605 if (ret)
3606 mutex_unlock(&fs_info->reclaim_bgs_lock);
3607 if (ret < 0)
3608 goto error;
3609 if (ret > 0)
3610 break;
3611
3612 leaf = path->nodes[0];
3613 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3614
3615 chunk = btrfs_item_ptr(leaf, path->slots[0],
3616 struct btrfs_chunk);
3617 chunk_type = btrfs_chunk_type(leaf, chunk);
3618 btrfs_release_path(path);
3619
3620 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
3621 ret = btrfs_relocate_chunk(fs_info, found_key.offset);
3622 if (ret == -ENOSPC)
3623 failed++;
3624 else
3625 BUG_ON(ret);
3626 }
3627 mutex_unlock(&fs_info->reclaim_bgs_lock);
3628
3629 if (found_key.offset == 0)
3630 break;
3631 key.offset = found_key.offset - 1;
3632 }
3633 ret = 0;
3634 if (failed && !retried) {
3635 failed = 0;
3636 retried = true;
3637 goto again;
3638 } else if (WARN_ON(failed && retried)) {
3639 ret = -ENOSPC;
3640 }
3641 error:
3642 btrfs_free_path(path);
3643 return ret;
3644 }
3645
3646 /*
3647 * return 1 : allocate a data chunk successfully,
3648 * return <0: errors during allocating a data chunk,
3649 * return 0 : no need to allocate a data chunk.
3650 */
btrfs_may_alloc_data_chunk(struct btrfs_fs_info * fs_info,u64 chunk_offset)3651 static int btrfs_may_alloc_data_chunk(struct btrfs_fs_info *fs_info,
3652 u64 chunk_offset)
3653 {
3654 struct btrfs_block_group *cache;
3655 u64 bytes_used;
3656 u64 chunk_type;
3657
3658 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3659 ASSERT(cache);
3660 chunk_type = cache->flags;
3661 btrfs_put_block_group(cache);
3662
3663 if (!(chunk_type & BTRFS_BLOCK_GROUP_DATA))
3664 return 0;
3665
3666 spin_lock(&fs_info->data_sinfo->lock);
3667 bytes_used = fs_info->data_sinfo->bytes_used;
3668 spin_unlock(&fs_info->data_sinfo->lock);
3669
3670 if (!bytes_used) {
3671 struct btrfs_trans_handle *trans;
3672 int ret;
3673
3674 trans = btrfs_join_transaction(fs_info->tree_root);
3675 if (IS_ERR(trans))
3676 return PTR_ERR(trans);
3677
3678 ret = btrfs_force_chunk_alloc(trans, BTRFS_BLOCK_GROUP_DATA);
3679 btrfs_end_transaction(trans);
3680 if (ret < 0)
3681 return ret;
3682 return 1;
3683 }
3684
3685 return 0;
3686 }
3687
btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args * cpu,const struct btrfs_disk_balance_args * disk)3688 static void btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args *cpu,
3689 const struct btrfs_disk_balance_args *disk)
3690 {
3691 memset(cpu, 0, sizeof(*cpu));
3692
3693 cpu->profiles = le64_to_cpu(disk->profiles);
3694 cpu->usage = le64_to_cpu(disk->usage);
3695 cpu->devid = le64_to_cpu(disk->devid);
3696 cpu->pstart = le64_to_cpu(disk->pstart);
3697 cpu->pend = le64_to_cpu(disk->pend);
3698 cpu->vstart = le64_to_cpu(disk->vstart);
3699 cpu->vend = le64_to_cpu(disk->vend);
3700 cpu->target = le64_to_cpu(disk->target);
3701 cpu->flags = le64_to_cpu(disk->flags);
3702 cpu->limit = le64_to_cpu(disk->limit);
3703 cpu->stripes_min = le32_to_cpu(disk->stripes_min);
3704 cpu->stripes_max = le32_to_cpu(disk->stripes_max);
3705 }
3706
btrfs_cpu_balance_args_to_disk(struct btrfs_disk_balance_args * disk,const struct btrfs_balance_args * cpu)3707 static void btrfs_cpu_balance_args_to_disk(struct btrfs_disk_balance_args *disk,
3708 const struct btrfs_balance_args *cpu)
3709 {
3710 memset(disk, 0, sizeof(*disk));
3711
3712 disk->profiles = cpu_to_le64(cpu->profiles);
3713 disk->usage = cpu_to_le64(cpu->usage);
3714 disk->devid = cpu_to_le64(cpu->devid);
3715 disk->pstart = cpu_to_le64(cpu->pstart);
3716 disk->pend = cpu_to_le64(cpu->pend);
3717 disk->vstart = cpu_to_le64(cpu->vstart);
3718 disk->vend = cpu_to_le64(cpu->vend);
3719 disk->target = cpu_to_le64(cpu->target);
3720 disk->flags = cpu_to_le64(cpu->flags);
3721 disk->limit = cpu_to_le64(cpu->limit);
3722 disk->stripes_min = cpu_to_le32(cpu->stripes_min);
3723 disk->stripes_max = cpu_to_le32(cpu->stripes_max);
3724 }
3725
insert_balance_item(struct btrfs_fs_info * fs_info,struct btrfs_balance_control * bctl)3726 static int insert_balance_item(struct btrfs_fs_info *fs_info,
3727 struct btrfs_balance_control *bctl)
3728 {
3729 struct btrfs_root *root = fs_info->tree_root;
3730 struct btrfs_trans_handle *trans;
3731 struct btrfs_balance_item *item;
3732 struct btrfs_disk_balance_args disk_bargs;
3733 struct btrfs_path *path;
3734 struct extent_buffer *leaf;
3735 struct btrfs_key key;
3736 int ret, err;
3737
3738 path = btrfs_alloc_path();
3739 if (!path)
3740 return -ENOMEM;
3741
3742 trans = btrfs_start_transaction(root, 0);
3743 if (IS_ERR(trans)) {
3744 btrfs_free_path(path);
3745 return PTR_ERR(trans);
3746 }
3747
3748 key.objectid = BTRFS_BALANCE_OBJECTID;
3749 key.type = BTRFS_TEMPORARY_ITEM_KEY;
3750 key.offset = 0;
3751
3752 ret = btrfs_insert_empty_item(trans, root, path, &key,
3753 sizeof(*item));
3754 if (ret)
3755 goto out;
3756
3757 leaf = path->nodes[0];
3758 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3759
3760 memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item));
3761
3762 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
3763 btrfs_set_balance_data(leaf, item, &disk_bargs);
3764 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
3765 btrfs_set_balance_meta(leaf, item, &disk_bargs);
3766 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
3767 btrfs_set_balance_sys(leaf, item, &disk_bargs);
3768 btrfs_set_balance_flags(leaf, item, bctl->flags);
3769 out:
3770 btrfs_free_path(path);
3771 err = btrfs_commit_transaction(trans);
3772 if (err && !ret)
3773 ret = err;
3774 return ret;
3775 }
3776
del_balance_item(struct btrfs_fs_info * fs_info)3777 static int del_balance_item(struct btrfs_fs_info *fs_info)
3778 {
3779 struct btrfs_root *root = fs_info->tree_root;
3780 struct btrfs_trans_handle *trans;
3781 struct btrfs_path *path;
3782 struct btrfs_key key;
3783 int ret, err;
3784
3785 path = btrfs_alloc_path();
3786 if (!path)
3787 return -ENOMEM;
3788
3789 trans = btrfs_start_transaction_fallback_global_rsv(root, 0);
3790 if (IS_ERR(trans)) {
3791 btrfs_free_path(path);
3792 return PTR_ERR(trans);
3793 }
3794
3795 key.objectid = BTRFS_BALANCE_OBJECTID;
3796 key.type = BTRFS_TEMPORARY_ITEM_KEY;
3797 key.offset = 0;
3798
3799 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3800 if (ret < 0)
3801 goto out;
3802 if (ret > 0) {
3803 ret = -ENOENT;
3804 goto out;
3805 }
3806
3807 ret = btrfs_del_item(trans, root, path);
3808 out:
3809 btrfs_free_path(path);
3810 err = btrfs_commit_transaction(trans);
3811 if (err && !ret)
3812 ret = err;
3813 return ret;
3814 }
3815
3816 /*
3817 * This is a heuristic used to reduce the number of chunks balanced on
3818 * resume after balance was interrupted.
3819 */
update_balance_args(struct btrfs_balance_control * bctl)3820 static void update_balance_args(struct btrfs_balance_control *bctl)
3821 {
3822 /*
3823 * Turn on soft mode for chunk types that were being converted.
3824 */
3825 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
3826 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
3827 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
3828 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
3829 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
3830 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
3831
3832 /*
3833 * Turn on usage filter if is not already used. The idea is
3834 * that chunks that we have already balanced should be
3835 * reasonably full. Don't do it for chunks that are being
3836 * converted - that will keep us from relocating unconverted
3837 * (albeit full) chunks.
3838 */
3839 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3840 !(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3841 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3842 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
3843 bctl->data.usage = 90;
3844 }
3845 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3846 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3847 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3848 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
3849 bctl->sys.usage = 90;
3850 }
3851 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3852 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3853 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3854 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
3855 bctl->meta.usage = 90;
3856 }
3857 }
3858
3859 /*
3860 * Clear the balance status in fs_info and delete the balance item from disk.
3861 */
reset_balance_state(struct btrfs_fs_info * fs_info)3862 static void reset_balance_state(struct btrfs_fs_info *fs_info)
3863 {
3864 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3865 int ret;
3866
3867 ASSERT(fs_info->balance_ctl);
3868
3869 spin_lock(&fs_info->balance_lock);
3870 fs_info->balance_ctl = NULL;
3871 spin_unlock(&fs_info->balance_lock);
3872
3873 kfree(bctl);
3874 ret = del_balance_item(fs_info);
3875 if (ret)
3876 btrfs_handle_fs_error(fs_info, ret, NULL);
3877 }
3878
3879 /*
3880 * Balance filters. Return 1 if chunk should be filtered out
3881 * (should not be balanced).
3882 */
chunk_profiles_filter(u64 chunk_type,struct btrfs_balance_args * bargs)3883 static int chunk_profiles_filter(u64 chunk_type,
3884 struct btrfs_balance_args *bargs)
3885 {
3886 chunk_type = chunk_to_extended(chunk_type) &
3887 BTRFS_EXTENDED_PROFILE_MASK;
3888
3889 if (bargs->profiles & chunk_type)
3890 return 0;
3891
3892 return 1;
3893 }
3894
chunk_usage_range_filter(struct btrfs_fs_info * fs_info,u64 chunk_offset,struct btrfs_balance_args * bargs)3895 static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
3896 struct btrfs_balance_args *bargs)
3897 {
3898 struct btrfs_block_group *cache;
3899 u64 chunk_used;
3900 u64 user_thresh_min;
3901 u64 user_thresh_max;
3902 int ret = 1;
3903
3904 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3905 chunk_used = cache->used;
3906
3907 if (bargs->usage_min == 0)
3908 user_thresh_min = 0;
3909 else
3910 user_thresh_min = mult_perc(cache->length, bargs->usage_min);
3911
3912 if (bargs->usage_max == 0)
3913 user_thresh_max = 1;
3914 else if (bargs->usage_max > 100)
3915 user_thresh_max = cache->length;
3916 else
3917 user_thresh_max = mult_perc(cache->length, bargs->usage_max);
3918
3919 if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max)
3920 ret = 0;
3921
3922 btrfs_put_block_group(cache);
3923 return ret;
3924 }
3925
chunk_usage_filter(struct btrfs_fs_info * fs_info,u64 chunk_offset,struct btrfs_balance_args * bargs)3926 static int chunk_usage_filter(struct btrfs_fs_info *fs_info,
3927 u64 chunk_offset, struct btrfs_balance_args *bargs)
3928 {
3929 struct btrfs_block_group *cache;
3930 u64 chunk_used, user_thresh;
3931 int ret = 1;
3932
3933 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3934 chunk_used = cache->used;
3935
3936 if (bargs->usage_min == 0)
3937 user_thresh = 1;
3938 else if (bargs->usage > 100)
3939 user_thresh = cache->length;
3940 else
3941 user_thresh = mult_perc(cache->length, bargs->usage);
3942
3943 if (chunk_used < user_thresh)
3944 ret = 0;
3945
3946 btrfs_put_block_group(cache);
3947 return ret;
3948 }
3949
chunk_devid_filter(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_balance_args * bargs)3950 static int chunk_devid_filter(struct extent_buffer *leaf,
3951 struct btrfs_chunk *chunk,
3952 struct btrfs_balance_args *bargs)
3953 {
3954 struct btrfs_stripe *stripe;
3955 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3956 int i;
3957
3958 for (i = 0; i < num_stripes; i++) {
3959 stripe = btrfs_stripe_nr(chunk, i);
3960 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
3961 return 0;
3962 }
3963
3964 return 1;
3965 }
3966
calc_data_stripes(u64 type,int num_stripes)3967 static u64 calc_data_stripes(u64 type, int num_stripes)
3968 {
3969 const int index = btrfs_bg_flags_to_raid_index(type);
3970 const int ncopies = btrfs_raid_array[index].ncopies;
3971 const int nparity = btrfs_raid_array[index].nparity;
3972
3973 return (num_stripes - nparity) / ncopies;
3974 }
3975
3976 /* [pstart, pend) */
chunk_drange_filter(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_balance_args * bargs)3977 static int chunk_drange_filter(struct extent_buffer *leaf,
3978 struct btrfs_chunk *chunk,
3979 struct btrfs_balance_args *bargs)
3980 {
3981 struct btrfs_stripe *stripe;
3982 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3983 u64 stripe_offset;
3984 u64 stripe_length;
3985 u64 type;
3986 int factor;
3987 int i;
3988
3989 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3990 return 0;
3991
3992 type = btrfs_chunk_type(leaf, chunk);
3993 factor = calc_data_stripes(type, num_stripes);
3994
3995 for (i = 0; i < num_stripes; i++) {
3996 stripe = btrfs_stripe_nr(chunk, i);
3997 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3998 continue;
3999
4000 stripe_offset = btrfs_stripe_offset(leaf, stripe);
4001 stripe_length = btrfs_chunk_length(leaf, chunk);
4002 stripe_length = div_u64(stripe_length, factor);
4003
4004 if (stripe_offset < bargs->pend &&
4005 stripe_offset + stripe_length > bargs->pstart)
4006 return 0;
4007 }
4008
4009 return 1;
4010 }
4011
4012 /* [vstart, vend) */
chunk_vrange_filter(struct extent_buffer * leaf,struct btrfs_chunk * chunk,u64 chunk_offset,struct btrfs_balance_args * bargs)4013 static int chunk_vrange_filter(struct extent_buffer *leaf,
4014 struct btrfs_chunk *chunk,
4015 u64 chunk_offset,
4016 struct btrfs_balance_args *bargs)
4017 {
4018 if (chunk_offset < bargs->vend &&
4019 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
4020 /* at least part of the chunk is inside this vrange */
4021 return 0;
4022
4023 return 1;
4024 }
4025
chunk_stripes_range_filter(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_balance_args * bargs)4026 static int chunk_stripes_range_filter(struct extent_buffer *leaf,
4027 struct btrfs_chunk *chunk,
4028 struct btrfs_balance_args *bargs)
4029 {
4030 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
4031
4032 if (bargs->stripes_min <= num_stripes
4033 && num_stripes <= bargs->stripes_max)
4034 return 0;
4035
4036 return 1;
4037 }
4038
chunk_soft_convert_filter(u64 chunk_type,struct btrfs_balance_args * bargs)4039 static int chunk_soft_convert_filter(u64 chunk_type,
4040 struct btrfs_balance_args *bargs)
4041 {
4042 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
4043 return 0;
4044
4045 chunk_type = chunk_to_extended(chunk_type) &
4046 BTRFS_EXTENDED_PROFILE_MASK;
4047
4048 if (bargs->target == chunk_type)
4049 return 1;
4050
4051 return 0;
4052 }
4053
should_balance_chunk(struct extent_buffer * leaf,struct btrfs_chunk * chunk,u64 chunk_offset)4054 static int should_balance_chunk(struct extent_buffer *leaf,
4055 struct btrfs_chunk *chunk, u64 chunk_offset)
4056 {
4057 struct btrfs_fs_info *fs_info = leaf->fs_info;
4058 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4059 struct btrfs_balance_args *bargs = NULL;
4060 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
4061
4062 /* type filter */
4063 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
4064 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
4065 return 0;
4066 }
4067
4068 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
4069 bargs = &bctl->data;
4070 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
4071 bargs = &bctl->sys;
4072 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
4073 bargs = &bctl->meta;
4074
4075 /* profiles filter */
4076 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
4077 chunk_profiles_filter(chunk_type, bargs)) {
4078 return 0;
4079 }
4080
4081 /* usage filter */
4082 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
4083 chunk_usage_filter(fs_info, chunk_offset, bargs)) {
4084 return 0;
4085 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
4086 chunk_usage_range_filter(fs_info, chunk_offset, bargs)) {
4087 return 0;
4088 }
4089
4090 /* devid filter */
4091 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
4092 chunk_devid_filter(leaf, chunk, bargs)) {
4093 return 0;
4094 }
4095
4096 /* drange filter, makes sense only with devid filter */
4097 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
4098 chunk_drange_filter(leaf, chunk, bargs)) {
4099 return 0;
4100 }
4101
4102 /* vrange filter */
4103 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
4104 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
4105 return 0;
4106 }
4107
4108 /* stripes filter */
4109 if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) &&
4110 chunk_stripes_range_filter(leaf, chunk, bargs)) {
4111 return 0;
4112 }
4113
4114 /* soft profile changing mode */
4115 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
4116 chunk_soft_convert_filter(chunk_type, bargs)) {
4117 return 0;
4118 }
4119
4120 /*
4121 * limited by count, must be the last filter
4122 */
4123 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
4124 if (bargs->limit == 0)
4125 return 0;
4126 else
4127 bargs->limit--;
4128 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) {
4129 /*
4130 * Same logic as the 'limit' filter; the minimum cannot be
4131 * determined here because we do not have the global information
4132 * about the count of all chunks that satisfy the filters.
4133 */
4134 if (bargs->limit_max == 0)
4135 return 0;
4136 else
4137 bargs->limit_max--;
4138 }
4139
4140 return 1;
4141 }
4142
__btrfs_balance(struct btrfs_fs_info * fs_info)4143 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
4144 {
4145 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4146 struct btrfs_root *chunk_root = fs_info->chunk_root;
4147 u64 chunk_type;
4148 struct btrfs_chunk *chunk;
4149 struct btrfs_path *path = NULL;
4150 struct btrfs_key key;
4151 struct btrfs_key found_key;
4152 struct extent_buffer *leaf;
4153 int slot;
4154 int ret;
4155 int enospc_errors = 0;
4156 bool counting = true;
4157 /* The single value limit and min/max limits use the same bytes in the */
4158 u64 limit_data = bctl->data.limit;
4159 u64 limit_meta = bctl->meta.limit;
4160 u64 limit_sys = bctl->sys.limit;
4161 u32 count_data = 0;
4162 u32 count_meta = 0;
4163 u32 count_sys = 0;
4164 int chunk_reserved = 0;
4165
4166 path = btrfs_alloc_path();
4167 if (!path) {
4168 ret = -ENOMEM;
4169 goto error;
4170 }
4171
4172 /* zero out stat counters */
4173 spin_lock(&fs_info->balance_lock);
4174 memset(&bctl->stat, 0, sizeof(bctl->stat));
4175 spin_unlock(&fs_info->balance_lock);
4176 again:
4177 if (!counting) {
4178 /*
4179 * The single value limit and min/max limits use the same bytes
4180 * in the
4181 */
4182 bctl->data.limit = limit_data;
4183 bctl->meta.limit = limit_meta;
4184 bctl->sys.limit = limit_sys;
4185 }
4186 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4187 key.offset = (u64)-1;
4188 key.type = BTRFS_CHUNK_ITEM_KEY;
4189
4190 while (1) {
4191 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
4192 atomic_read(&fs_info->balance_cancel_req)) {
4193 ret = -ECANCELED;
4194 goto error;
4195 }
4196
4197 mutex_lock(&fs_info->reclaim_bgs_lock);
4198 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
4199 if (ret < 0) {
4200 mutex_unlock(&fs_info->reclaim_bgs_lock);
4201 goto error;
4202 }
4203
4204 /*
4205 * this shouldn't happen, it means the last relocate
4206 * failed
4207 */
4208 if (ret == 0)
4209 BUG(); /* FIXME break ? */
4210
4211 ret = btrfs_previous_item(chunk_root, path, 0,
4212 BTRFS_CHUNK_ITEM_KEY);
4213 if (ret) {
4214 mutex_unlock(&fs_info->reclaim_bgs_lock);
4215 ret = 0;
4216 break;
4217 }
4218
4219 leaf = path->nodes[0];
4220 slot = path->slots[0];
4221 btrfs_item_key_to_cpu(leaf, &found_key, slot);
4222
4223 if (found_key.objectid != key.objectid) {
4224 mutex_unlock(&fs_info->reclaim_bgs_lock);
4225 break;
4226 }
4227
4228 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
4229 chunk_type = btrfs_chunk_type(leaf, chunk);
4230
4231 if (!counting) {
4232 spin_lock(&fs_info->balance_lock);
4233 bctl->stat.considered++;
4234 spin_unlock(&fs_info->balance_lock);
4235 }
4236
4237 ret = should_balance_chunk(leaf, chunk, found_key.offset);
4238
4239 btrfs_release_path(path);
4240 if (!ret) {
4241 mutex_unlock(&fs_info->reclaim_bgs_lock);
4242 goto loop;
4243 }
4244
4245 if (counting) {
4246 mutex_unlock(&fs_info->reclaim_bgs_lock);
4247 spin_lock(&fs_info->balance_lock);
4248 bctl->stat.expected++;
4249 spin_unlock(&fs_info->balance_lock);
4250
4251 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
4252 count_data++;
4253 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
4254 count_sys++;
4255 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
4256 count_meta++;
4257
4258 goto loop;
4259 }
4260
4261 /*
4262 * Apply limit_min filter, no need to check if the LIMITS
4263 * filter is used, limit_min is 0 by default
4264 */
4265 if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
4266 count_data < bctl->data.limit_min)
4267 || ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) &&
4268 count_meta < bctl->meta.limit_min)
4269 || ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) &&
4270 count_sys < bctl->sys.limit_min)) {
4271 mutex_unlock(&fs_info->reclaim_bgs_lock);
4272 goto loop;
4273 }
4274
4275 if (!chunk_reserved) {
4276 /*
4277 * We may be relocating the only data chunk we have,
4278 * which could potentially end up with losing data's
4279 * raid profile, so lets allocate an empty one in
4280 * advance.
4281 */
4282 ret = btrfs_may_alloc_data_chunk(fs_info,
4283 found_key.offset);
4284 if (ret < 0) {
4285 mutex_unlock(&fs_info->reclaim_bgs_lock);
4286 goto error;
4287 } else if (ret == 1) {
4288 chunk_reserved = 1;
4289 }
4290 }
4291
4292 ret = btrfs_relocate_chunk(fs_info, found_key.offset);
4293 mutex_unlock(&fs_info->reclaim_bgs_lock);
4294 if (ret == -ENOSPC) {
4295 enospc_errors++;
4296 } else if (ret == -ETXTBSY) {
4297 btrfs_info(fs_info,
4298 "skipping relocation of block group %llu due to active swapfile",
4299 found_key.offset);
4300 ret = 0;
4301 } else if (ret) {
4302 goto error;
4303 } else {
4304 spin_lock(&fs_info->balance_lock);
4305 bctl->stat.completed++;
4306 spin_unlock(&fs_info->balance_lock);
4307 }
4308 loop:
4309 if (found_key.offset == 0)
4310 break;
4311 key.offset = found_key.offset - 1;
4312 }
4313
4314 if (counting) {
4315 btrfs_release_path(path);
4316 counting = false;
4317 goto again;
4318 }
4319 error:
4320 btrfs_free_path(path);
4321 if (enospc_errors) {
4322 btrfs_info(fs_info, "%d enospc errors during balance",
4323 enospc_errors);
4324 if (!ret)
4325 ret = -ENOSPC;
4326 }
4327
4328 return ret;
4329 }
4330
4331 /*
4332 * See if a given profile is valid and reduced.
4333 *
4334 * @flags: profile to validate
4335 * @extended: if true @flags is treated as an extended profile
4336 */
alloc_profile_is_valid(u64 flags,int extended)4337 static int alloc_profile_is_valid(u64 flags, int extended)
4338 {
4339 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
4340 BTRFS_BLOCK_GROUP_PROFILE_MASK);
4341
4342 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
4343
4344 /* 1) check that all other bits are zeroed */
4345 if (flags & ~mask)
4346 return 0;
4347
4348 /* 2) see if profile is reduced */
4349 if (flags == 0)
4350 return !extended; /* "0" is valid for usual profiles */
4351
4352 return has_single_bit_set(flags);
4353 }
4354
4355 /*
4356 * Validate target profile against allowed profiles and return true if it's OK.
4357 * Otherwise print the error message and return false.
4358 */
validate_convert_profile(struct btrfs_fs_info * fs_info,const struct btrfs_balance_args * bargs,u64 allowed,const char * type)4359 static inline int validate_convert_profile(struct btrfs_fs_info *fs_info,
4360 const struct btrfs_balance_args *bargs,
4361 u64 allowed, const char *type)
4362 {
4363 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
4364 return true;
4365
4366 /* Profile is valid and does not have bits outside of the allowed set */
4367 if (alloc_profile_is_valid(bargs->target, 1) &&
4368 (bargs->target & ~allowed) == 0)
4369 return true;
4370
4371 btrfs_err(fs_info, "balance: invalid convert %s profile %s",
4372 type, btrfs_bg_type_to_raid_name(bargs->target));
4373 return false;
4374 }
4375
4376 /*
4377 * Fill @buf with textual description of balance filter flags @bargs, up to
4378 * @size_buf including the terminating null. The output may be trimmed if it
4379 * does not fit into the provided buffer.
4380 */
describe_balance_args(struct btrfs_balance_args * bargs,char * buf,u32 size_buf)4381 static void describe_balance_args(struct btrfs_balance_args *bargs, char *buf,
4382 u32 size_buf)
4383 {
4384 int ret;
4385 u32 size_bp = size_buf;
4386 char *bp = buf;
4387 u64 flags = bargs->flags;
4388 char tmp_buf[128] = {'\0'};
4389
4390 if (!flags)
4391 return;
4392
4393 #define CHECK_APPEND_NOARG(a) \
4394 do { \
4395 ret = snprintf(bp, size_bp, (a)); \
4396 if (ret < 0 || ret >= size_bp) \
4397 goto out_overflow; \
4398 size_bp -= ret; \
4399 bp += ret; \
4400 } while (0)
4401
4402 #define CHECK_APPEND_1ARG(a, v1) \
4403 do { \
4404 ret = snprintf(bp, size_bp, (a), (v1)); \
4405 if (ret < 0 || ret >= size_bp) \
4406 goto out_overflow; \
4407 size_bp -= ret; \
4408 bp += ret; \
4409 } while (0)
4410
4411 #define CHECK_APPEND_2ARG(a, v1, v2) \
4412 do { \
4413 ret = snprintf(bp, size_bp, (a), (v1), (v2)); \
4414 if (ret < 0 || ret >= size_bp) \
4415 goto out_overflow; \
4416 size_bp -= ret; \
4417 bp += ret; \
4418 } while (0)
4419
4420 if (flags & BTRFS_BALANCE_ARGS_CONVERT)
4421 CHECK_APPEND_1ARG("convert=%s,",
4422 btrfs_bg_type_to_raid_name(bargs->target));
4423
4424 if (flags & BTRFS_BALANCE_ARGS_SOFT)
4425 CHECK_APPEND_NOARG("soft,");
4426
4427 if (flags & BTRFS_BALANCE_ARGS_PROFILES) {
4428 btrfs_describe_block_groups(bargs->profiles, tmp_buf,
4429 sizeof(tmp_buf));
4430 CHECK_APPEND_1ARG("profiles=%s,", tmp_buf);
4431 }
4432
4433 if (flags & BTRFS_BALANCE_ARGS_USAGE)
4434 CHECK_APPEND_1ARG("usage=%llu,", bargs->usage);
4435
4436 if (flags & BTRFS_BALANCE_ARGS_USAGE_RANGE)
4437 CHECK_APPEND_2ARG("usage=%u..%u,",
4438 bargs->usage_min, bargs->usage_max);
4439
4440 if (flags & BTRFS_BALANCE_ARGS_DEVID)
4441 CHECK_APPEND_1ARG("devid=%llu,", bargs->devid);
4442
4443 if (flags & BTRFS_BALANCE_ARGS_DRANGE)
4444 CHECK_APPEND_2ARG("drange=%llu..%llu,",
4445 bargs->pstart, bargs->pend);
4446
4447 if (flags & BTRFS_BALANCE_ARGS_VRANGE)
4448 CHECK_APPEND_2ARG("vrange=%llu..%llu,",
4449 bargs->vstart, bargs->vend);
4450
4451 if (flags & BTRFS_BALANCE_ARGS_LIMIT)
4452 CHECK_APPEND_1ARG("limit=%llu,", bargs->limit);
4453
4454 if (flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)
4455 CHECK_APPEND_2ARG("limit=%u..%u,",
4456 bargs->limit_min, bargs->limit_max);
4457
4458 if (flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE)
4459 CHECK_APPEND_2ARG("stripes=%u..%u,",
4460 bargs->stripes_min, bargs->stripes_max);
4461
4462 #undef CHECK_APPEND_2ARG
4463 #undef CHECK_APPEND_1ARG
4464 #undef CHECK_APPEND_NOARG
4465
4466 out_overflow:
4467
4468 if (size_bp < size_buf)
4469 buf[size_buf - size_bp - 1] = '\0'; /* remove last , */
4470 else
4471 buf[0] = '\0';
4472 }
4473
describe_balance_start_or_resume(struct btrfs_fs_info * fs_info)4474 static void describe_balance_start_or_resume(struct btrfs_fs_info *fs_info)
4475 {
4476 u32 size_buf = 1024;
4477 char tmp_buf[192] = {'\0'};
4478 char *buf;
4479 char *bp;
4480 u32 size_bp = size_buf;
4481 int ret;
4482 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4483
4484 buf = kzalloc(size_buf, GFP_KERNEL);
4485 if (!buf)
4486 return;
4487
4488 bp = buf;
4489
4490 #define CHECK_APPEND_1ARG(a, v1) \
4491 do { \
4492 ret = snprintf(bp, size_bp, (a), (v1)); \
4493 if (ret < 0 || ret >= size_bp) \
4494 goto out_overflow; \
4495 size_bp -= ret; \
4496 bp += ret; \
4497 } while (0)
4498
4499 if (bctl->flags & BTRFS_BALANCE_FORCE)
4500 CHECK_APPEND_1ARG("%s", "-f ");
4501
4502 if (bctl->flags & BTRFS_BALANCE_DATA) {
4503 describe_balance_args(&bctl->data, tmp_buf, sizeof(tmp_buf));
4504 CHECK_APPEND_1ARG("-d%s ", tmp_buf);
4505 }
4506
4507 if (bctl->flags & BTRFS_BALANCE_METADATA) {
4508 describe_balance_args(&bctl->meta, tmp_buf, sizeof(tmp_buf));
4509 CHECK_APPEND_1ARG("-m%s ", tmp_buf);
4510 }
4511
4512 if (bctl->flags & BTRFS_BALANCE_SYSTEM) {
4513 describe_balance_args(&bctl->sys, tmp_buf, sizeof(tmp_buf));
4514 CHECK_APPEND_1ARG("-s%s ", tmp_buf);
4515 }
4516
4517 #undef CHECK_APPEND_1ARG
4518
4519 out_overflow:
4520
4521 if (size_bp < size_buf)
4522 buf[size_buf - size_bp - 1] = '\0'; /* remove last " " */
4523 btrfs_info(fs_info, "balance: %s %s",
4524 (bctl->flags & BTRFS_BALANCE_RESUME) ?
4525 "resume" : "start", buf);
4526
4527 kfree(buf);
4528 }
4529
4530 /*
4531 * Should be called with balance mutexe held
4532 */
btrfs_balance(struct btrfs_fs_info * fs_info,struct btrfs_balance_control * bctl,struct btrfs_ioctl_balance_args * bargs)4533 int btrfs_balance(struct btrfs_fs_info *fs_info,
4534 struct btrfs_balance_control *bctl,
4535 struct btrfs_ioctl_balance_args *bargs)
4536 {
4537 u64 meta_target, data_target;
4538 u64 allowed;
4539 int mixed = 0;
4540 int ret;
4541 u64 num_devices;
4542 unsigned seq;
4543 bool reducing_redundancy;
4544 bool paused = false;
4545 int i;
4546
4547 if (btrfs_fs_closing(fs_info) ||
4548 atomic_read(&fs_info->balance_pause_req) ||
4549 btrfs_should_cancel_balance(fs_info)) {
4550 ret = -EINVAL;
4551 goto out;
4552 }
4553
4554 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
4555 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
4556 mixed = 1;
4557
4558 /*
4559 * In case of mixed groups both data and meta should be picked,
4560 * and identical options should be given for both of them.
4561 */
4562 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
4563 if (mixed && (bctl->flags & allowed)) {
4564 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
4565 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
4566 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
4567 btrfs_err(fs_info,
4568 "balance: mixed groups data and metadata options must be the same");
4569 ret = -EINVAL;
4570 goto out;
4571 }
4572 }
4573
4574 /*
4575 * rw_devices will not change at the moment, device add/delete/replace
4576 * are exclusive
4577 */
4578 num_devices = fs_info->fs_devices->rw_devices;
4579
4580 /*
4581 * SINGLE profile on-disk has no profile bit, but in-memory we have a
4582 * special bit for it, to make it easier to distinguish. Thus we need
4583 * to set it manually, or balance would refuse the profile.
4584 */
4585 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
4586 for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++)
4587 if (num_devices >= btrfs_raid_array[i].devs_min)
4588 allowed |= btrfs_raid_array[i].bg_flag;
4589
4590 if (!validate_convert_profile(fs_info, &bctl->data, allowed, "data") ||
4591 !validate_convert_profile(fs_info, &bctl->meta, allowed, "metadata") ||
4592 !validate_convert_profile(fs_info, &bctl->sys, allowed, "system")) {
4593 ret = -EINVAL;
4594 goto out;
4595 }
4596
4597 /*
4598 * Allow to reduce metadata or system integrity only if force set for
4599 * profiles with redundancy (copies, parity)
4600 */
4601 allowed = 0;
4602 for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) {
4603 if (btrfs_raid_array[i].ncopies >= 2 ||
4604 btrfs_raid_array[i].tolerated_failures >= 1)
4605 allowed |= btrfs_raid_array[i].bg_flag;
4606 }
4607 do {
4608 seq = read_seqbegin(&fs_info->profiles_lock);
4609
4610 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
4611 (fs_info->avail_system_alloc_bits & allowed) &&
4612 !(bctl->sys.target & allowed)) ||
4613 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
4614 (fs_info->avail_metadata_alloc_bits & allowed) &&
4615 !(bctl->meta.target & allowed)))
4616 reducing_redundancy = true;
4617 else
4618 reducing_redundancy = false;
4619
4620 /* if we're not converting, the target field is uninitialized */
4621 meta_target = (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) ?
4622 bctl->meta.target : fs_info->avail_metadata_alloc_bits;
4623 data_target = (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) ?
4624 bctl->data.target : fs_info->avail_data_alloc_bits;
4625 } while (read_seqretry(&fs_info->profiles_lock, seq));
4626
4627 if (reducing_redundancy) {
4628 if (bctl->flags & BTRFS_BALANCE_FORCE) {
4629 btrfs_info(fs_info,
4630 "balance: force reducing metadata redundancy");
4631 } else {
4632 btrfs_err(fs_info,
4633 "balance: reduces metadata redundancy, use --force if you want this");
4634 ret = -EINVAL;
4635 goto out;
4636 }
4637 }
4638
4639 if (btrfs_get_num_tolerated_disk_barrier_failures(meta_target) <
4640 btrfs_get_num_tolerated_disk_barrier_failures(data_target)) {
4641 btrfs_warn(fs_info,
4642 "balance: metadata profile %s has lower redundancy than data profile %s",
4643 btrfs_bg_type_to_raid_name(meta_target),
4644 btrfs_bg_type_to_raid_name(data_target));
4645 }
4646
4647 ret = insert_balance_item(fs_info, bctl);
4648 if (ret && ret != -EEXIST)
4649 goto out;
4650
4651 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
4652 BUG_ON(ret == -EEXIST);
4653 BUG_ON(fs_info->balance_ctl);
4654 spin_lock(&fs_info->balance_lock);
4655 fs_info->balance_ctl = bctl;
4656 spin_unlock(&fs_info->balance_lock);
4657 } else {
4658 BUG_ON(ret != -EEXIST);
4659 spin_lock(&fs_info->balance_lock);
4660 update_balance_args(bctl);
4661 spin_unlock(&fs_info->balance_lock);
4662 }
4663
4664 ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4665 set_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
4666 describe_balance_start_or_resume(fs_info);
4667 mutex_unlock(&fs_info->balance_mutex);
4668
4669 ret = __btrfs_balance(fs_info);
4670
4671 mutex_lock(&fs_info->balance_mutex);
4672 if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
4673 btrfs_info(fs_info, "balance: paused");
4674 btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
4675 paused = true;
4676 }
4677 /*
4678 * Balance can be canceled by:
4679 *
4680 * - Regular cancel request
4681 * Then ret == -ECANCELED and balance_cancel_req > 0
4682 *
4683 * - Fatal signal to "btrfs" process
4684 * Either the signal caught by wait_reserve_ticket() and callers
4685 * got -EINTR, or caught by btrfs_should_cancel_balance() and
4686 * got -ECANCELED.
4687 * Either way, in this case balance_cancel_req = 0, and
4688 * ret == -EINTR or ret == -ECANCELED.
4689 *
4690 * So here we only check the return value to catch canceled balance.
4691 */
4692 else if (ret == -ECANCELED || ret == -EINTR)
4693 btrfs_info(fs_info, "balance: canceled");
4694 else
4695 btrfs_info(fs_info, "balance: ended with status: %d", ret);
4696
4697 clear_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
4698
4699 if (bargs) {
4700 memset(bargs, 0, sizeof(*bargs));
4701 btrfs_update_ioctl_balance_args(fs_info, bargs);
4702 }
4703
4704 /* We didn't pause, we can clean everything up. */
4705 if (!paused) {
4706 reset_balance_state(fs_info);
4707 btrfs_exclop_finish(fs_info);
4708 }
4709
4710 wake_up(&fs_info->balance_wait_q);
4711
4712 return ret;
4713 out:
4714 if (bctl->flags & BTRFS_BALANCE_RESUME)
4715 reset_balance_state(fs_info);
4716 else
4717 kfree(bctl);
4718 btrfs_exclop_finish(fs_info);
4719
4720 return ret;
4721 }
4722
balance_kthread(void * data)4723 static int balance_kthread(void *data)
4724 {
4725 struct btrfs_fs_info *fs_info = data;
4726 int ret = 0;
4727
4728 sb_start_write(fs_info->sb);
4729 mutex_lock(&fs_info->balance_mutex);
4730 if (fs_info->balance_ctl)
4731 ret = btrfs_balance(fs_info, fs_info->balance_ctl, NULL);
4732 mutex_unlock(&fs_info->balance_mutex);
4733 sb_end_write(fs_info->sb);
4734
4735 return ret;
4736 }
4737
btrfs_resume_balance_async(struct btrfs_fs_info * fs_info)4738 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
4739 {
4740 struct task_struct *tsk;
4741
4742 mutex_lock(&fs_info->balance_mutex);
4743 if (!fs_info->balance_ctl) {
4744 mutex_unlock(&fs_info->balance_mutex);
4745 return 0;
4746 }
4747 mutex_unlock(&fs_info->balance_mutex);
4748
4749 if (btrfs_test_opt(fs_info, SKIP_BALANCE)) {
4750 btrfs_info(fs_info, "balance: resume skipped");
4751 return 0;
4752 }
4753
4754 spin_lock(&fs_info->super_lock);
4755 ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
4756 fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;
4757 spin_unlock(&fs_info->super_lock);
4758 /*
4759 * A ro->rw remount sequence should continue with the paused balance
4760 * regardless of who pauses it, system or the user as of now, so set
4761 * the resume flag.
4762 */
4763 spin_lock(&fs_info->balance_lock);
4764 fs_info->balance_ctl->flags |= BTRFS_BALANCE_RESUME;
4765 spin_unlock(&fs_info->balance_lock);
4766
4767 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
4768 return PTR_ERR_OR_ZERO(tsk);
4769 }
4770
btrfs_recover_balance(struct btrfs_fs_info * fs_info)4771 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
4772 {
4773 struct btrfs_balance_control *bctl;
4774 struct btrfs_balance_item *item;
4775 struct btrfs_disk_balance_args disk_bargs;
4776 struct btrfs_path *path;
4777 struct extent_buffer *leaf;
4778 struct btrfs_key key;
4779 int ret;
4780
4781 path = btrfs_alloc_path();
4782 if (!path)
4783 return -ENOMEM;
4784
4785 key.objectid = BTRFS_BALANCE_OBJECTID;
4786 key.type = BTRFS_TEMPORARY_ITEM_KEY;
4787 key.offset = 0;
4788
4789 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
4790 if (ret < 0)
4791 goto out;
4792 if (ret > 0) { /* ret = -ENOENT; */
4793 ret = 0;
4794 goto out;
4795 }
4796
4797 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4798 if (!bctl) {
4799 ret = -ENOMEM;
4800 goto out;
4801 }
4802
4803 leaf = path->nodes[0];
4804 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
4805
4806 bctl->flags = btrfs_balance_flags(leaf, item);
4807 bctl->flags |= BTRFS_BALANCE_RESUME;
4808
4809 btrfs_balance_data(leaf, item, &disk_bargs);
4810 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
4811 btrfs_balance_meta(leaf, item, &disk_bargs);
4812 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
4813 btrfs_balance_sys(leaf, item, &disk_bargs);
4814 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
4815
4816 /*
4817 * This should never happen, as the paused balance state is recovered
4818 * during mount without any chance of other exclusive ops to collide.
4819 *
4820 * This gives the exclusive op status to balance and keeps in paused
4821 * state until user intervention (cancel or umount). If the ownership
4822 * cannot be assigned, show a message but do not fail. The balance
4823 * is in a paused state and must have fs_info::balance_ctl properly
4824 * set up.
4825 */
4826 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED))
4827 btrfs_warn(fs_info,
4828 "balance: cannot set exclusive op status, resume manually");
4829
4830 btrfs_release_path(path);
4831
4832 mutex_lock(&fs_info->balance_mutex);
4833 BUG_ON(fs_info->balance_ctl);
4834 spin_lock(&fs_info->balance_lock);
4835 fs_info->balance_ctl = bctl;
4836 spin_unlock(&fs_info->balance_lock);
4837 mutex_unlock(&fs_info->balance_mutex);
4838 out:
4839 btrfs_free_path(path);
4840 return ret;
4841 }
4842
btrfs_pause_balance(struct btrfs_fs_info * fs_info)4843 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
4844 {
4845 int ret = 0;
4846
4847 mutex_lock(&fs_info->balance_mutex);
4848 if (!fs_info->balance_ctl) {
4849 mutex_unlock(&fs_info->balance_mutex);
4850 return -ENOTCONN;
4851 }
4852
4853 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4854 atomic_inc(&fs_info->balance_pause_req);
4855 mutex_unlock(&fs_info->balance_mutex);
4856
4857 wait_event(fs_info->balance_wait_q,
4858 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4859
4860 mutex_lock(&fs_info->balance_mutex);
4861 /* we are good with balance_ctl ripped off from under us */
4862 BUG_ON(test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4863 atomic_dec(&fs_info->balance_pause_req);
4864 } else {
4865 ret = -ENOTCONN;
4866 }
4867
4868 mutex_unlock(&fs_info->balance_mutex);
4869 return ret;
4870 }
4871
btrfs_cancel_balance(struct btrfs_fs_info * fs_info)4872 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
4873 {
4874 mutex_lock(&fs_info->balance_mutex);
4875 if (!fs_info->balance_ctl) {
4876 mutex_unlock(&fs_info->balance_mutex);
4877 return -ENOTCONN;
4878 }
4879
4880 /*
4881 * A paused balance with the item stored on disk can be resumed at
4882 * mount time if the mount is read-write. Otherwise it's still paused
4883 * and we must not allow cancelling as it deletes the item.
4884 */
4885 if (sb_rdonly(fs_info->sb)) {
4886 mutex_unlock(&fs_info->balance_mutex);
4887 return -EROFS;
4888 }
4889
4890 atomic_inc(&fs_info->balance_cancel_req);
4891 /*
4892 * if we are running just wait and return, balance item is
4893 * deleted in btrfs_balance in this case
4894 */
4895 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4896 mutex_unlock(&fs_info->balance_mutex);
4897 wait_event(fs_info->balance_wait_q,
4898 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4899 mutex_lock(&fs_info->balance_mutex);
4900 } else {
4901 mutex_unlock(&fs_info->balance_mutex);
4902 /*
4903 * Lock released to allow other waiters to continue, we'll
4904 * reexamine the status again.
4905 */
4906 mutex_lock(&fs_info->balance_mutex);
4907
4908 if (fs_info->balance_ctl) {
4909 reset_balance_state(fs_info);
4910 btrfs_exclop_finish(fs_info);
4911 btrfs_info(fs_info, "balance: canceled");
4912 }
4913 }
4914
4915 ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4916 atomic_dec(&fs_info->balance_cancel_req);
4917 mutex_unlock(&fs_info->balance_mutex);
4918 return 0;
4919 }
4920
4921 /*
4922 * shrinking a device means finding all of the device extents past
4923 * the new size, and then following the back refs to the chunks.
4924 * The chunk relocation code actually frees the device extent
4925 */
btrfs_shrink_device(struct btrfs_device * device,u64 new_size)4926 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
4927 {
4928 struct btrfs_fs_info *fs_info = device->fs_info;
4929 struct btrfs_root *root = fs_info->dev_root;
4930 struct btrfs_trans_handle *trans;
4931 struct btrfs_dev_extent *dev_extent = NULL;
4932 struct btrfs_path *path;
4933 u64 length;
4934 u64 chunk_offset;
4935 int ret;
4936 int slot;
4937 int failed = 0;
4938 bool retried = false;
4939 struct extent_buffer *l;
4940 struct btrfs_key key;
4941 struct btrfs_super_block *super_copy = fs_info->super_copy;
4942 u64 old_total = btrfs_super_total_bytes(super_copy);
4943 u64 old_size = btrfs_device_get_total_bytes(device);
4944 u64 diff;
4945 u64 start;
4946 u64 free_diff = 0;
4947
4948 new_size = round_down(new_size, fs_info->sectorsize);
4949 start = new_size;
4950 diff = round_down(old_size - new_size, fs_info->sectorsize);
4951
4952 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
4953 return -EINVAL;
4954
4955 path = btrfs_alloc_path();
4956 if (!path)
4957 return -ENOMEM;
4958
4959 path->reada = READA_BACK;
4960
4961 trans = btrfs_start_transaction(root, 0);
4962 if (IS_ERR(trans)) {
4963 btrfs_free_path(path);
4964 return PTR_ERR(trans);
4965 }
4966
4967 mutex_lock(&fs_info->chunk_mutex);
4968
4969 btrfs_device_set_total_bytes(device, new_size);
4970 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
4971 device->fs_devices->total_rw_bytes -= diff;
4972
4973 /*
4974 * The new free_chunk_space is new_size - used, so we have to
4975 * subtract the delta of the old free_chunk_space which included
4976 * old_size - used. If used > new_size then just subtract this
4977 * entire device's free space.
4978 */
4979 if (device->bytes_used < new_size)
4980 free_diff = (old_size - device->bytes_used) -
4981 (new_size - device->bytes_used);
4982 else
4983 free_diff = old_size - device->bytes_used;
4984 atomic64_sub(free_diff, &fs_info->free_chunk_space);
4985 }
4986
4987 /*
4988 * Once the device's size has been set to the new size, ensure all
4989 * in-memory chunks are synced to disk so that the loop below sees them
4990 * and relocates them accordingly.
4991 */
4992 if (contains_pending_extent(device, &start, diff)) {
4993 mutex_unlock(&fs_info->chunk_mutex);
4994 ret = btrfs_commit_transaction(trans);
4995 if (ret)
4996 goto done;
4997 } else {
4998 mutex_unlock(&fs_info->chunk_mutex);
4999 btrfs_end_transaction(trans);
5000 }
5001
5002 again:
5003 key.objectid = device->devid;
5004 key.offset = (u64)-1;
5005 key.type = BTRFS_DEV_EXTENT_KEY;
5006
5007 do {
5008 mutex_lock(&fs_info->reclaim_bgs_lock);
5009 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5010 if (ret < 0) {
5011 mutex_unlock(&fs_info->reclaim_bgs_lock);
5012 goto done;
5013 }
5014
5015 ret = btrfs_previous_item(root, path, 0, key.type);
5016 if (ret) {
5017 mutex_unlock(&fs_info->reclaim_bgs_lock);
5018 if (ret < 0)
5019 goto done;
5020 ret = 0;
5021 btrfs_release_path(path);
5022 break;
5023 }
5024
5025 l = path->nodes[0];
5026 slot = path->slots[0];
5027 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
5028
5029 if (key.objectid != device->devid) {
5030 mutex_unlock(&fs_info->reclaim_bgs_lock);
5031 btrfs_release_path(path);
5032 break;
5033 }
5034
5035 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
5036 length = btrfs_dev_extent_length(l, dev_extent);
5037
5038 if (key.offset + length <= new_size) {
5039 mutex_unlock(&fs_info->reclaim_bgs_lock);
5040 btrfs_release_path(path);
5041 break;
5042 }
5043
5044 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
5045 btrfs_release_path(path);
5046
5047 /*
5048 * We may be relocating the only data chunk we have,
5049 * which could potentially end up with losing data's
5050 * raid profile, so lets allocate an empty one in
5051 * advance.
5052 */
5053 ret = btrfs_may_alloc_data_chunk(fs_info, chunk_offset);
5054 if (ret < 0) {
5055 mutex_unlock(&fs_info->reclaim_bgs_lock);
5056 goto done;
5057 }
5058
5059 ret = btrfs_relocate_chunk(fs_info, chunk_offset);
5060 mutex_unlock(&fs_info->reclaim_bgs_lock);
5061 if (ret == -ENOSPC) {
5062 failed++;
5063 } else if (ret) {
5064 if (ret == -ETXTBSY) {
5065 btrfs_warn(fs_info,
5066 "could not shrink block group %llu due to active swapfile",
5067 chunk_offset);
5068 }
5069 goto done;
5070 }
5071 } while (key.offset-- > 0);
5072
5073 if (failed && !retried) {
5074 failed = 0;
5075 retried = true;
5076 goto again;
5077 } else if (failed && retried) {
5078 ret = -ENOSPC;
5079 goto done;
5080 }
5081
5082 /* Shrinking succeeded, else we would be at "done". */
5083 trans = btrfs_start_transaction(root, 0);
5084 if (IS_ERR(trans)) {
5085 ret = PTR_ERR(trans);
5086 goto done;
5087 }
5088
5089 mutex_lock(&fs_info->chunk_mutex);
5090 /* Clear all state bits beyond the shrunk device size */
5091 clear_extent_bits(&device->alloc_state, new_size, (u64)-1,
5092 CHUNK_STATE_MASK);
5093
5094 btrfs_device_set_disk_total_bytes(device, new_size);
5095 if (list_empty(&device->post_commit_list))
5096 list_add_tail(&device->post_commit_list,
5097 &trans->transaction->dev_update_list);
5098
5099 WARN_ON(diff > old_total);
5100 btrfs_set_super_total_bytes(super_copy,
5101 round_down(old_total - diff, fs_info->sectorsize));
5102 mutex_unlock(&fs_info->chunk_mutex);
5103
5104 btrfs_reserve_chunk_metadata(trans, false);
5105 /* Now btrfs_update_device() will change the on-disk size. */
5106 ret = btrfs_update_device(trans, device);
5107 btrfs_trans_release_chunk_metadata(trans);
5108 if (ret < 0) {
5109 btrfs_abort_transaction(trans, ret);
5110 btrfs_end_transaction(trans);
5111 } else {
5112 ret = btrfs_commit_transaction(trans);
5113 }
5114 done:
5115 btrfs_free_path(path);
5116 if (ret) {
5117 mutex_lock(&fs_info->chunk_mutex);
5118 btrfs_device_set_total_bytes(device, old_size);
5119 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
5120 device->fs_devices->total_rw_bytes += diff;
5121 atomic64_add(free_diff, &fs_info->free_chunk_space);
5122 }
5123 mutex_unlock(&fs_info->chunk_mutex);
5124 }
5125 return ret;
5126 }
5127
btrfs_add_system_chunk(struct btrfs_fs_info * fs_info,struct btrfs_key * key,struct btrfs_chunk * chunk,int item_size)5128 static int btrfs_add_system_chunk(struct btrfs_fs_info *fs_info,
5129 struct btrfs_key *key,
5130 struct btrfs_chunk *chunk, int item_size)
5131 {
5132 struct btrfs_super_block *super_copy = fs_info->super_copy;
5133 struct btrfs_disk_key disk_key;
5134 u32 array_size;
5135 u8 *ptr;
5136
5137 lockdep_assert_held(&fs_info->chunk_mutex);
5138
5139 array_size = btrfs_super_sys_array_size(super_copy);
5140 if (array_size + item_size + sizeof(disk_key)
5141 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
5142 return -EFBIG;
5143
5144 ptr = super_copy->sys_chunk_array + array_size;
5145 btrfs_cpu_key_to_disk(&disk_key, key);
5146 memcpy(ptr, &disk_key, sizeof(disk_key));
5147 ptr += sizeof(disk_key);
5148 memcpy(ptr, chunk, item_size);
5149 item_size += sizeof(disk_key);
5150 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
5151
5152 return 0;
5153 }
5154
5155 /*
5156 * sort the devices in descending order by max_avail, total_avail
5157 */
btrfs_cmp_device_info(const void * a,const void * b)5158 static int btrfs_cmp_device_info(const void *a, const void *b)
5159 {
5160 const struct btrfs_device_info *di_a = a;
5161 const struct btrfs_device_info *di_b = b;
5162
5163 if (di_a->max_avail > di_b->max_avail)
5164 return -1;
5165 if (di_a->max_avail < di_b->max_avail)
5166 return 1;
5167 if (di_a->total_avail > di_b->total_avail)
5168 return -1;
5169 if (di_a->total_avail < di_b->total_avail)
5170 return 1;
5171 return 0;
5172 }
5173
check_raid56_incompat_flag(struct btrfs_fs_info * info,u64 type)5174 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
5175 {
5176 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
5177 return;
5178
5179 btrfs_set_fs_incompat(info, RAID56);
5180 }
5181
check_raid1c34_incompat_flag(struct btrfs_fs_info * info,u64 type)5182 static void check_raid1c34_incompat_flag(struct btrfs_fs_info *info, u64 type)
5183 {
5184 if (!(type & (BTRFS_BLOCK_GROUP_RAID1C3 | BTRFS_BLOCK_GROUP_RAID1C4)))
5185 return;
5186
5187 btrfs_set_fs_incompat(info, RAID1C34);
5188 }
5189
5190 /*
5191 * Structure used internally for btrfs_create_chunk() function.
5192 * Wraps needed parameters.
5193 */
5194 struct alloc_chunk_ctl {
5195 u64 start;
5196 u64 type;
5197 /* Total number of stripes to allocate */
5198 int num_stripes;
5199 /* sub_stripes info for map */
5200 int sub_stripes;
5201 /* Stripes per device */
5202 int dev_stripes;
5203 /* Maximum number of devices to use */
5204 int devs_max;
5205 /* Minimum number of devices to use */
5206 int devs_min;
5207 /* ndevs has to be a multiple of this */
5208 int devs_increment;
5209 /* Number of copies */
5210 int ncopies;
5211 /* Number of stripes worth of bytes to store parity information */
5212 int nparity;
5213 u64 max_stripe_size;
5214 u64 max_chunk_size;
5215 u64 dev_extent_min;
5216 u64 stripe_size;
5217 u64 chunk_size;
5218 int ndevs;
5219 };
5220
init_alloc_chunk_ctl_policy_regular(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl)5221 static void init_alloc_chunk_ctl_policy_regular(
5222 struct btrfs_fs_devices *fs_devices,
5223 struct alloc_chunk_ctl *ctl)
5224 {
5225 struct btrfs_space_info *space_info;
5226
5227 space_info = btrfs_find_space_info(fs_devices->fs_info, ctl->type);
5228 ASSERT(space_info);
5229
5230 ctl->max_chunk_size = READ_ONCE(space_info->chunk_size);
5231 ctl->max_stripe_size = min_t(u64, ctl->max_chunk_size, SZ_1G);
5232
5233 if (ctl->type & BTRFS_BLOCK_GROUP_SYSTEM)
5234 ctl->devs_max = min_t(int, ctl->devs_max, BTRFS_MAX_DEVS_SYS_CHUNK);
5235
5236 /* We don't want a chunk larger than 10% of writable space */
5237 ctl->max_chunk_size = min(mult_perc(fs_devices->total_rw_bytes, 10),
5238 ctl->max_chunk_size);
5239 ctl->dev_extent_min = btrfs_stripe_nr_to_offset(ctl->dev_stripes);
5240 }
5241
init_alloc_chunk_ctl_policy_zoned(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl)5242 static void init_alloc_chunk_ctl_policy_zoned(
5243 struct btrfs_fs_devices *fs_devices,
5244 struct alloc_chunk_ctl *ctl)
5245 {
5246 u64 zone_size = fs_devices->fs_info->zone_size;
5247 u64 limit;
5248 int min_num_stripes = ctl->devs_min * ctl->dev_stripes;
5249 int min_data_stripes = (min_num_stripes - ctl->nparity) / ctl->ncopies;
5250 u64 min_chunk_size = min_data_stripes * zone_size;
5251 u64 type = ctl->type;
5252
5253 ctl->max_stripe_size = zone_size;
5254 if (type & BTRFS_BLOCK_GROUP_DATA) {
5255 ctl->max_chunk_size = round_down(BTRFS_MAX_DATA_CHUNK_SIZE,
5256 zone_size);
5257 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
5258 ctl->max_chunk_size = ctl->max_stripe_size;
5259 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
5260 ctl->max_chunk_size = 2 * ctl->max_stripe_size;
5261 ctl->devs_max = min_t(int, ctl->devs_max,
5262 BTRFS_MAX_DEVS_SYS_CHUNK);
5263 } else {
5264 BUG();
5265 }
5266
5267 /* We don't want a chunk larger than 10% of writable space */
5268 limit = max(round_down(mult_perc(fs_devices->total_rw_bytes, 10),
5269 zone_size),
5270 min_chunk_size);
5271 ctl->max_chunk_size = min(limit, ctl->max_chunk_size);
5272 ctl->dev_extent_min = zone_size * ctl->dev_stripes;
5273 }
5274
init_alloc_chunk_ctl(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl)5275 static void init_alloc_chunk_ctl(struct btrfs_fs_devices *fs_devices,
5276 struct alloc_chunk_ctl *ctl)
5277 {
5278 int index = btrfs_bg_flags_to_raid_index(ctl->type);
5279
5280 ctl->sub_stripes = btrfs_raid_array[index].sub_stripes;
5281 ctl->dev_stripes = btrfs_raid_array[index].dev_stripes;
5282 ctl->devs_max = btrfs_raid_array[index].devs_max;
5283 if (!ctl->devs_max)
5284 ctl->devs_max = BTRFS_MAX_DEVS(fs_devices->fs_info);
5285 ctl->devs_min = btrfs_raid_array[index].devs_min;
5286 ctl->devs_increment = btrfs_raid_array[index].devs_increment;
5287 ctl->ncopies = btrfs_raid_array[index].ncopies;
5288 ctl->nparity = btrfs_raid_array[index].nparity;
5289 ctl->ndevs = 0;
5290
5291 switch (fs_devices->chunk_alloc_policy) {
5292 case BTRFS_CHUNK_ALLOC_REGULAR:
5293 init_alloc_chunk_ctl_policy_regular(fs_devices, ctl);
5294 break;
5295 case BTRFS_CHUNK_ALLOC_ZONED:
5296 init_alloc_chunk_ctl_policy_zoned(fs_devices, ctl);
5297 break;
5298 default:
5299 BUG();
5300 }
5301 }
5302
gather_device_info(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5303 static int gather_device_info(struct btrfs_fs_devices *fs_devices,
5304 struct alloc_chunk_ctl *ctl,
5305 struct btrfs_device_info *devices_info)
5306 {
5307 struct btrfs_fs_info *info = fs_devices->fs_info;
5308 struct btrfs_device *device;
5309 u64 total_avail;
5310 u64 dev_extent_want = ctl->max_stripe_size * ctl->dev_stripes;
5311 int ret;
5312 int ndevs = 0;
5313 u64 max_avail;
5314 u64 dev_offset;
5315
5316 /*
5317 * in the first pass through the devices list, we gather information
5318 * about the available holes on each device.
5319 */
5320 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
5321 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
5322 WARN(1, KERN_ERR
5323 "BTRFS: read-only device in alloc_list\n");
5324 continue;
5325 }
5326
5327 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
5328 &device->dev_state) ||
5329 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
5330 continue;
5331
5332 if (device->total_bytes > device->bytes_used)
5333 total_avail = device->total_bytes - device->bytes_used;
5334 else
5335 total_avail = 0;
5336
5337 /* If there is no space on this device, skip it. */
5338 if (total_avail < ctl->dev_extent_min)
5339 continue;
5340
5341 ret = find_free_dev_extent(device, dev_extent_want, &dev_offset,
5342 &max_avail);
5343 if (ret && ret != -ENOSPC)
5344 return ret;
5345
5346 if (ret == 0)
5347 max_avail = dev_extent_want;
5348
5349 if (max_avail < ctl->dev_extent_min) {
5350 if (btrfs_test_opt(info, ENOSPC_DEBUG))
5351 btrfs_debug(info,
5352 "%s: devid %llu has no free space, have=%llu want=%llu",
5353 __func__, device->devid, max_avail,
5354 ctl->dev_extent_min);
5355 continue;
5356 }
5357
5358 if (ndevs == fs_devices->rw_devices) {
5359 WARN(1, "%s: found more than %llu devices\n",
5360 __func__, fs_devices->rw_devices);
5361 break;
5362 }
5363 devices_info[ndevs].dev_offset = dev_offset;
5364 devices_info[ndevs].max_avail = max_avail;
5365 devices_info[ndevs].total_avail = total_avail;
5366 devices_info[ndevs].dev = device;
5367 ++ndevs;
5368 }
5369 ctl->ndevs = ndevs;
5370
5371 /*
5372 * now sort the devices by hole size / available space
5373 */
5374 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
5375 btrfs_cmp_device_info, NULL);
5376
5377 return 0;
5378 }
5379
decide_stripe_size_regular(struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5380 static int decide_stripe_size_regular(struct alloc_chunk_ctl *ctl,
5381 struct btrfs_device_info *devices_info)
5382 {
5383 /* Number of stripes that count for block group size */
5384 int data_stripes;
5385
5386 /*
5387 * The primary goal is to maximize the number of stripes, so use as
5388 * many devices as possible, even if the stripes are not maximum sized.
5389 *
5390 * The DUP profile stores more than one stripe per device, the
5391 * max_avail is the total size so we have to adjust.
5392 */
5393 ctl->stripe_size = div_u64(devices_info[ctl->ndevs - 1].max_avail,
5394 ctl->dev_stripes);
5395 ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
5396
5397 /* This will have to be fixed for RAID1 and RAID10 over more drives */
5398 data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
5399
5400 /*
5401 * Use the number of data stripes to figure out how big this chunk is
5402 * really going to be in terms of logical address space, and compare
5403 * that answer with the max chunk size. If it's higher, we try to
5404 * reduce stripe_size.
5405 */
5406 if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
5407 /*
5408 * Reduce stripe_size, round it up to a 16MB boundary again and
5409 * then use it, unless it ends up being even bigger than the
5410 * previous value we had already.
5411 */
5412 ctl->stripe_size = min(round_up(div_u64(ctl->max_chunk_size,
5413 data_stripes), SZ_16M),
5414 ctl->stripe_size);
5415 }
5416
5417 /* Stripe size should not go beyond 1G. */
5418 ctl->stripe_size = min_t(u64, ctl->stripe_size, SZ_1G);
5419
5420 /* Align to BTRFS_STRIPE_LEN */
5421 ctl->stripe_size = round_down(ctl->stripe_size, BTRFS_STRIPE_LEN);
5422 ctl->chunk_size = ctl->stripe_size * data_stripes;
5423
5424 return 0;
5425 }
5426
decide_stripe_size_zoned(struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5427 static int decide_stripe_size_zoned(struct alloc_chunk_ctl *ctl,
5428 struct btrfs_device_info *devices_info)
5429 {
5430 u64 zone_size = devices_info[0].dev->zone_info->zone_size;
5431 /* Number of stripes that count for block group size */
5432 int data_stripes;
5433
5434 /*
5435 * It should hold because:
5436 * dev_extent_min == dev_extent_want == zone_size * dev_stripes
5437 */
5438 ASSERT(devices_info[ctl->ndevs - 1].max_avail == ctl->dev_extent_min);
5439
5440 ctl->stripe_size = zone_size;
5441 ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
5442 data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
5443
5444 /* stripe_size is fixed in zoned filesystem. Reduce ndevs instead. */
5445 if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
5446 ctl->ndevs = div_u64(div_u64(ctl->max_chunk_size * ctl->ncopies,
5447 ctl->stripe_size) + ctl->nparity,
5448 ctl->dev_stripes);
5449 ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
5450 data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
5451 ASSERT(ctl->stripe_size * data_stripes <= ctl->max_chunk_size);
5452 }
5453
5454 ctl->chunk_size = ctl->stripe_size * data_stripes;
5455
5456 return 0;
5457 }
5458
decide_stripe_size(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5459 static int decide_stripe_size(struct btrfs_fs_devices *fs_devices,
5460 struct alloc_chunk_ctl *ctl,
5461 struct btrfs_device_info *devices_info)
5462 {
5463 struct btrfs_fs_info *info = fs_devices->fs_info;
5464
5465 /*
5466 * Round down to number of usable stripes, devs_increment can be any
5467 * number so we can't use round_down() that requires power of 2, while
5468 * rounddown is safe.
5469 */
5470 ctl->ndevs = rounddown(ctl->ndevs, ctl->devs_increment);
5471
5472 if (ctl->ndevs < ctl->devs_min) {
5473 if (btrfs_test_opt(info, ENOSPC_DEBUG)) {
5474 btrfs_debug(info,
5475 "%s: not enough devices with free space: have=%d minimum required=%d",
5476 __func__, ctl->ndevs, ctl->devs_min);
5477 }
5478 return -ENOSPC;
5479 }
5480
5481 ctl->ndevs = min(ctl->ndevs, ctl->devs_max);
5482
5483 switch (fs_devices->chunk_alloc_policy) {
5484 case BTRFS_CHUNK_ALLOC_REGULAR:
5485 return decide_stripe_size_regular(ctl, devices_info);
5486 case BTRFS_CHUNK_ALLOC_ZONED:
5487 return decide_stripe_size_zoned(ctl, devices_info);
5488 default:
5489 BUG();
5490 }
5491 }
5492
chunk_map_device_set_bits(struct btrfs_chunk_map * map,unsigned int bits)5493 static void chunk_map_device_set_bits(struct btrfs_chunk_map *map, unsigned int bits)
5494 {
5495 for (int i = 0; i < map->num_stripes; i++) {
5496 struct btrfs_io_stripe *stripe = &map->stripes[i];
5497 struct btrfs_device *device = stripe->dev;
5498
5499 set_extent_bit(&device->alloc_state, stripe->physical,
5500 stripe->physical + map->stripe_size - 1,
5501 bits | EXTENT_NOWAIT, NULL);
5502 }
5503 }
5504
chunk_map_device_clear_bits(struct btrfs_chunk_map * map,unsigned int bits)5505 static void chunk_map_device_clear_bits(struct btrfs_chunk_map *map, unsigned int bits)
5506 {
5507 for (int i = 0; i < map->num_stripes; i++) {
5508 struct btrfs_io_stripe *stripe = &map->stripes[i];
5509 struct btrfs_device *device = stripe->dev;
5510
5511 __clear_extent_bit(&device->alloc_state, stripe->physical,
5512 stripe->physical + map->stripe_size - 1,
5513 bits | EXTENT_NOWAIT,
5514 NULL, NULL);
5515 }
5516 }
5517
btrfs_remove_chunk_map(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map)5518 void btrfs_remove_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map)
5519 {
5520 write_lock(&fs_info->mapping_tree_lock);
5521 rb_erase_cached(&map->rb_node, &fs_info->mapping_tree);
5522 RB_CLEAR_NODE(&map->rb_node);
5523 chunk_map_device_clear_bits(map, CHUNK_ALLOCATED);
5524 write_unlock(&fs_info->mapping_tree_lock);
5525
5526 /* Once for the tree reference. */
5527 btrfs_free_chunk_map(map);
5528 }
5529
btrfs_chunk_map_cmp(const struct rb_node * new,const struct rb_node * exist)5530 static int btrfs_chunk_map_cmp(const struct rb_node *new,
5531 const struct rb_node *exist)
5532 {
5533 const struct btrfs_chunk_map *new_map =
5534 rb_entry(new, struct btrfs_chunk_map, rb_node);
5535 const struct btrfs_chunk_map *exist_map =
5536 rb_entry(exist, struct btrfs_chunk_map, rb_node);
5537
5538 if (new_map->start == exist_map->start)
5539 return 0;
5540 if (new_map->start < exist_map->start)
5541 return -1;
5542 return 1;
5543 }
5544
5545 EXPORT_FOR_TESTS
btrfs_add_chunk_map(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map)5546 int btrfs_add_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map)
5547 {
5548 struct rb_node *exist;
5549
5550 write_lock(&fs_info->mapping_tree_lock);
5551 exist = rb_find_add_cached(&map->rb_node, &fs_info->mapping_tree,
5552 btrfs_chunk_map_cmp);
5553
5554 if (exist) {
5555 write_unlock(&fs_info->mapping_tree_lock);
5556 return -EEXIST;
5557 }
5558 chunk_map_device_set_bits(map, CHUNK_ALLOCATED);
5559 chunk_map_device_clear_bits(map, CHUNK_TRIMMED);
5560 write_unlock(&fs_info->mapping_tree_lock);
5561
5562 return 0;
5563 }
5564
5565 EXPORT_FOR_TESTS
btrfs_alloc_chunk_map(int num_stripes,gfp_t gfp)5566 struct btrfs_chunk_map *btrfs_alloc_chunk_map(int num_stripes, gfp_t gfp)
5567 {
5568 struct btrfs_chunk_map *map;
5569
5570 map = kmalloc(btrfs_chunk_map_size(num_stripes), gfp);
5571 if (!map)
5572 return NULL;
5573
5574 refcount_set(&map->refs, 1);
5575 RB_CLEAR_NODE(&map->rb_node);
5576
5577 return map;
5578 }
5579
create_chunk(struct btrfs_trans_handle * trans,struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5580 static struct btrfs_block_group *create_chunk(struct btrfs_trans_handle *trans,
5581 struct alloc_chunk_ctl *ctl,
5582 struct btrfs_device_info *devices_info)
5583 {
5584 struct btrfs_fs_info *info = trans->fs_info;
5585 struct btrfs_chunk_map *map;
5586 struct btrfs_block_group *block_group;
5587 u64 start = ctl->start;
5588 u64 type = ctl->type;
5589 int ret;
5590
5591 map = btrfs_alloc_chunk_map(ctl->num_stripes, GFP_NOFS);
5592 if (!map)
5593 return ERR_PTR(-ENOMEM);
5594
5595 map->start = start;
5596 map->chunk_len = ctl->chunk_size;
5597 map->stripe_size = ctl->stripe_size;
5598 map->type = type;
5599 map->io_align = BTRFS_STRIPE_LEN;
5600 map->io_width = BTRFS_STRIPE_LEN;
5601 map->sub_stripes = ctl->sub_stripes;
5602 map->num_stripes = ctl->num_stripes;
5603
5604 for (int i = 0; i < ctl->ndevs; i++) {
5605 for (int j = 0; j < ctl->dev_stripes; j++) {
5606 int s = i * ctl->dev_stripes + j;
5607 map->stripes[s].dev = devices_info[i].dev;
5608 map->stripes[s].physical = devices_info[i].dev_offset +
5609 j * ctl->stripe_size;
5610 }
5611 }
5612
5613 trace_btrfs_chunk_alloc(info, map, start, ctl->chunk_size);
5614
5615 ret = btrfs_add_chunk_map(info, map);
5616 if (ret) {
5617 btrfs_free_chunk_map(map);
5618 return ERR_PTR(ret);
5619 }
5620
5621 block_group = btrfs_make_block_group(trans, type, start, ctl->chunk_size);
5622 if (IS_ERR(block_group)) {
5623 btrfs_remove_chunk_map(info, map);
5624 return block_group;
5625 }
5626
5627 for (int i = 0; i < map->num_stripes; i++) {
5628 struct btrfs_device *dev = map->stripes[i].dev;
5629
5630 btrfs_device_set_bytes_used(dev,
5631 dev->bytes_used + ctl->stripe_size);
5632 if (list_empty(&dev->post_commit_list))
5633 list_add_tail(&dev->post_commit_list,
5634 &trans->transaction->dev_update_list);
5635 }
5636
5637 atomic64_sub(ctl->stripe_size * map->num_stripes,
5638 &info->free_chunk_space);
5639
5640 check_raid56_incompat_flag(info, type);
5641 check_raid1c34_incompat_flag(info, type);
5642
5643 return block_group;
5644 }
5645
btrfs_create_chunk(struct btrfs_trans_handle * trans,u64 type)5646 struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
5647 u64 type)
5648 {
5649 struct btrfs_fs_info *info = trans->fs_info;
5650 struct btrfs_fs_devices *fs_devices = info->fs_devices;
5651 struct btrfs_device_info *devices_info = NULL;
5652 struct alloc_chunk_ctl ctl;
5653 struct btrfs_block_group *block_group;
5654 int ret;
5655
5656 lockdep_assert_held(&info->chunk_mutex);
5657
5658 if (!alloc_profile_is_valid(type, 0)) {
5659 ASSERT(0);
5660 return ERR_PTR(-EINVAL);
5661 }
5662
5663 if (list_empty(&fs_devices->alloc_list)) {
5664 if (btrfs_test_opt(info, ENOSPC_DEBUG))
5665 btrfs_debug(info, "%s: no writable device", __func__);
5666 return ERR_PTR(-ENOSPC);
5667 }
5668
5669 if (!(type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
5670 btrfs_err(info, "invalid chunk type 0x%llx requested", type);
5671 ASSERT(0);
5672 return ERR_PTR(-EINVAL);
5673 }
5674
5675 ctl.start = find_next_chunk(info);
5676 ctl.type = type;
5677 init_alloc_chunk_ctl(fs_devices, &ctl);
5678
5679 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
5680 GFP_NOFS);
5681 if (!devices_info)
5682 return ERR_PTR(-ENOMEM);
5683
5684 ret = gather_device_info(fs_devices, &ctl, devices_info);
5685 if (ret < 0) {
5686 block_group = ERR_PTR(ret);
5687 goto out;
5688 }
5689
5690 ret = decide_stripe_size(fs_devices, &ctl, devices_info);
5691 if (ret < 0) {
5692 block_group = ERR_PTR(ret);
5693 goto out;
5694 }
5695
5696 block_group = create_chunk(trans, &ctl, devices_info);
5697
5698 out:
5699 kfree(devices_info);
5700 return block_group;
5701 }
5702
5703 /*
5704 * This function, btrfs_chunk_alloc_add_chunk_item(), typically belongs to the
5705 * phase 1 of chunk allocation. It belongs to phase 2 only when allocating system
5706 * chunks.
5707 *
5708 * See the comment at btrfs_chunk_alloc() for details about the chunk allocation
5709 * phases.
5710 */
btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle * trans,struct btrfs_block_group * bg)5711 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
5712 struct btrfs_block_group *bg)
5713 {
5714 struct btrfs_fs_info *fs_info = trans->fs_info;
5715 struct btrfs_root *chunk_root = fs_info->chunk_root;
5716 struct btrfs_key key;
5717 struct btrfs_chunk *chunk;
5718 struct btrfs_stripe *stripe;
5719 struct btrfs_chunk_map *map;
5720 size_t item_size;
5721 int i;
5722 int ret;
5723
5724 /*
5725 * We take the chunk_mutex for 2 reasons:
5726 *
5727 * 1) Updates and insertions in the chunk btree must be done while holding
5728 * the chunk_mutex, as well as updating the system chunk array in the
5729 * superblock. See the comment on top of btrfs_chunk_alloc() for the
5730 * details;
5731 *
5732 * 2) To prevent races with the final phase of a device replace operation
5733 * that replaces the device object associated with the map's stripes,
5734 * because the device object's id can change at any time during that
5735 * final phase of the device replace operation
5736 * (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the
5737 * replaced device and then see it with an ID of BTRFS_DEV_REPLACE_DEVID,
5738 * which would cause a failure when updating the device item, which does
5739 * not exists, or persisting a stripe of the chunk item with such ID.
5740 * Here we can't use the device_list_mutex because our caller already
5741 * has locked the chunk_mutex, and the final phase of device replace
5742 * acquires both mutexes - first the device_list_mutex and then the
5743 * chunk_mutex. Using any of those two mutexes protects us from a
5744 * concurrent device replace.
5745 */
5746 lockdep_assert_held(&fs_info->chunk_mutex);
5747
5748 map = btrfs_get_chunk_map(fs_info, bg->start, bg->length);
5749 if (IS_ERR(map)) {
5750 ret = PTR_ERR(map);
5751 btrfs_abort_transaction(trans, ret);
5752 return ret;
5753 }
5754
5755 item_size = btrfs_chunk_item_size(map->num_stripes);
5756
5757 chunk = kzalloc(item_size, GFP_NOFS);
5758 if (!chunk) {
5759 ret = -ENOMEM;
5760 btrfs_abort_transaction(trans, ret);
5761 goto out;
5762 }
5763
5764 for (i = 0; i < map->num_stripes; i++) {
5765 struct btrfs_device *device = map->stripes[i].dev;
5766
5767 ret = btrfs_update_device(trans, device);
5768 if (ret)
5769 goto out;
5770 }
5771
5772 stripe = &chunk->stripe;
5773 for (i = 0; i < map->num_stripes; i++) {
5774 struct btrfs_device *device = map->stripes[i].dev;
5775 const u64 dev_offset = map->stripes[i].physical;
5776
5777 btrfs_set_stack_stripe_devid(stripe, device->devid);
5778 btrfs_set_stack_stripe_offset(stripe, dev_offset);
5779 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
5780 stripe++;
5781 }
5782
5783 btrfs_set_stack_chunk_length(chunk, bg->length);
5784 btrfs_set_stack_chunk_owner(chunk, BTRFS_EXTENT_TREE_OBJECTID);
5785 btrfs_set_stack_chunk_stripe_len(chunk, BTRFS_STRIPE_LEN);
5786 btrfs_set_stack_chunk_type(chunk, map->type);
5787 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
5788 btrfs_set_stack_chunk_io_align(chunk, BTRFS_STRIPE_LEN);
5789 btrfs_set_stack_chunk_io_width(chunk, BTRFS_STRIPE_LEN);
5790 btrfs_set_stack_chunk_sector_size(chunk, fs_info->sectorsize);
5791 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
5792
5793 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
5794 key.type = BTRFS_CHUNK_ITEM_KEY;
5795 key.offset = bg->start;
5796
5797 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
5798 if (ret)
5799 goto out;
5800
5801 set_bit(BLOCK_GROUP_FLAG_CHUNK_ITEM_INSERTED, &bg->runtime_flags);
5802
5803 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
5804 ret = btrfs_add_system_chunk(fs_info, &key, chunk, item_size);
5805 if (ret)
5806 goto out;
5807 }
5808
5809 out:
5810 kfree(chunk);
5811 btrfs_free_chunk_map(map);
5812 return ret;
5813 }
5814
init_first_rw_device(struct btrfs_trans_handle * trans)5815 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans)
5816 {
5817 struct btrfs_fs_info *fs_info = trans->fs_info;
5818 u64 alloc_profile;
5819 struct btrfs_block_group *meta_bg;
5820 struct btrfs_block_group *sys_bg;
5821
5822 /*
5823 * When adding a new device for sprouting, the seed device is read-only
5824 * so we must first allocate a metadata and a system chunk. But before
5825 * adding the block group items to the extent, device and chunk btrees,
5826 * we must first:
5827 *
5828 * 1) Create both chunks without doing any changes to the btrees, as
5829 * otherwise we would get -ENOSPC since the block groups from the
5830 * seed device are read-only;
5831 *
5832 * 2) Add the device item for the new sprout device - finishing the setup
5833 * of a new block group requires updating the device item in the chunk
5834 * btree, so it must exist when we attempt to do it. The previous step
5835 * ensures this does not fail with -ENOSPC.
5836 *
5837 * After that we can add the block group items to their btrees:
5838 * update existing device item in the chunk btree, add a new block group
5839 * item to the extent btree, add a new chunk item to the chunk btree and
5840 * finally add the new device extent items to the devices btree.
5841 */
5842
5843 alloc_profile = btrfs_metadata_alloc_profile(fs_info);
5844 meta_bg = btrfs_create_chunk(trans, alloc_profile);
5845 if (IS_ERR(meta_bg))
5846 return PTR_ERR(meta_bg);
5847
5848 alloc_profile = btrfs_system_alloc_profile(fs_info);
5849 sys_bg = btrfs_create_chunk(trans, alloc_profile);
5850 if (IS_ERR(sys_bg))
5851 return PTR_ERR(sys_bg);
5852
5853 return 0;
5854 }
5855
btrfs_chunk_max_errors(struct btrfs_chunk_map * map)5856 static inline int btrfs_chunk_max_errors(struct btrfs_chunk_map *map)
5857 {
5858 const int index = btrfs_bg_flags_to_raid_index(map->type);
5859
5860 return btrfs_raid_array[index].tolerated_failures;
5861 }
5862
btrfs_chunk_writeable(struct btrfs_fs_info * fs_info,u64 chunk_offset)5863 bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset)
5864 {
5865 struct btrfs_chunk_map *map;
5866 int miss_ndevs = 0;
5867 int i;
5868 bool ret = true;
5869
5870 map = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
5871 if (IS_ERR(map))
5872 return false;
5873
5874 for (i = 0; i < map->num_stripes; i++) {
5875 if (test_bit(BTRFS_DEV_STATE_MISSING,
5876 &map->stripes[i].dev->dev_state)) {
5877 miss_ndevs++;
5878 continue;
5879 }
5880 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE,
5881 &map->stripes[i].dev->dev_state)) {
5882 ret = false;
5883 goto end;
5884 }
5885 }
5886
5887 /*
5888 * If the number of missing devices is larger than max errors, we can
5889 * not write the data into that chunk successfully.
5890 */
5891 if (miss_ndevs > btrfs_chunk_max_errors(map))
5892 ret = false;
5893 end:
5894 btrfs_free_chunk_map(map);
5895 return ret;
5896 }
5897
btrfs_mapping_tree_free(struct btrfs_fs_info * fs_info)5898 void btrfs_mapping_tree_free(struct btrfs_fs_info *fs_info)
5899 {
5900 write_lock(&fs_info->mapping_tree_lock);
5901 while (!RB_EMPTY_ROOT(&fs_info->mapping_tree.rb_root)) {
5902 struct btrfs_chunk_map *map;
5903 struct rb_node *node;
5904
5905 node = rb_first_cached(&fs_info->mapping_tree);
5906 map = rb_entry(node, struct btrfs_chunk_map, rb_node);
5907 rb_erase_cached(&map->rb_node, &fs_info->mapping_tree);
5908 RB_CLEAR_NODE(&map->rb_node);
5909 chunk_map_device_clear_bits(map, CHUNK_ALLOCATED);
5910 /* Once for the tree ref. */
5911 btrfs_free_chunk_map(map);
5912 cond_resched_rwlock_write(&fs_info->mapping_tree_lock);
5913 }
5914 write_unlock(&fs_info->mapping_tree_lock);
5915 }
5916
btrfs_chunk_map_num_copies(const struct btrfs_chunk_map * map)5917 static int btrfs_chunk_map_num_copies(const struct btrfs_chunk_map *map)
5918 {
5919 enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(map->type);
5920
5921 if (map->type & BTRFS_BLOCK_GROUP_RAID5)
5922 return 2;
5923
5924 /*
5925 * There could be two corrupted data stripes, we need to loop retry in
5926 * order to rebuild the correct data.
5927 *
5928 * Fail a stripe at a time on every retry except the stripe under
5929 * reconstruction.
5930 */
5931 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5932 return map->num_stripes;
5933
5934 /* Non-RAID56, use their ncopies from btrfs_raid_array. */
5935 return btrfs_raid_array[index].ncopies;
5936 }
5937
btrfs_num_copies(struct btrfs_fs_info * fs_info,u64 logical,u64 len)5938 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
5939 {
5940 struct btrfs_chunk_map *map;
5941 int ret;
5942
5943 map = btrfs_get_chunk_map(fs_info, logical, len);
5944 if (IS_ERR(map))
5945 /*
5946 * We could return errors for these cases, but that could get
5947 * ugly and we'd probably do the same thing which is just not do
5948 * anything else and exit, so return 1 so the callers don't try
5949 * to use other copies.
5950 */
5951 return 1;
5952
5953 ret = btrfs_chunk_map_num_copies(map);
5954 btrfs_free_chunk_map(map);
5955 return ret;
5956 }
5957
btrfs_full_stripe_len(struct btrfs_fs_info * fs_info,u64 logical)5958 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
5959 u64 logical)
5960 {
5961 struct btrfs_chunk_map *map;
5962 unsigned long len = fs_info->sectorsize;
5963
5964 if (!btrfs_fs_incompat(fs_info, RAID56))
5965 return len;
5966
5967 map = btrfs_get_chunk_map(fs_info, logical, len);
5968
5969 if (!WARN_ON(IS_ERR(map))) {
5970 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
5971 len = btrfs_stripe_nr_to_offset(nr_data_stripes(map));
5972 btrfs_free_chunk_map(map);
5973 }
5974 return len;
5975 }
5976
5977 #ifdef CONFIG_BTRFS_EXPERIMENTAL
btrfs_read_preferred(struct btrfs_chunk_map * map,int first,int num_stripes)5978 static int btrfs_read_preferred(struct btrfs_chunk_map *map, int first, int num_stripes)
5979 {
5980 for (int index = first; index < first + num_stripes; index++) {
5981 const struct btrfs_device *device = map->stripes[index].dev;
5982
5983 if (device->devid == READ_ONCE(device->fs_devices->read_devid))
5984 return index;
5985 }
5986
5987 /* If no read-preferred device is set use the first stripe. */
5988 return first;
5989 }
5990
5991 struct stripe_mirror {
5992 u64 devid;
5993 int num;
5994 };
5995
btrfs_cmp_devid(const void * a,const void * b)5996 static int btrfs_cmp_devid(const void *a, const void *b)
5997 {
5998 const struct stripe_mirror *s1 = (const struct stripe_mirror *)a;
5999 const struct stripe_mirror *s2 = (const struct stripe_mirror *)b;
6000
6001 if (s1->devid < s2->devid)
6002 return -1;
6003 if (s1->devid > s2->devid)
6004 return 1;
6005 return 0;
6006 }
6007
6008 /*
6009 * Select a stripe for reading using the round-robin algorithm.
6010 *
6011 * 1. Compute the read cycle as the total sectors read divided by the minimum
6012 * sectors per device.
6013 * 2. Determine the stripe number for the current read by taking the modulus
6014 * of the read cycle with the total number of stripes:
6015 *
6016 * stripe index = (total sectors / min sectors per dev) % num stripes
6017 *
6018 * The calculated stripe index is then used to select the corresponding device
6019 * from the list of devices, which is ordered by devid.
6020 */
btrfs_read_rr(const struct btrfs_chunk_map * map,int first,int num_stripes)6021 static int btrfs_read_rr(const struct btrfs_chunk_map *map, int first, int num_stripes)
6022 {
6023 struct stripe_mirror stripes[BTRFS_RAID1_MAX_MIRRORS] = { 0 };
6024 struct btrfs_device *device = map->stripes[first].dev;
6025 struct btrfs_fs_info *fs_info = device->fs_devices->fs_info;
6026 unsigned int read_cycle;
6027 unsigned int total_reads;
6028 unsigned int min_reads_per_dev;
6029
6030 total_reads = percpu_counter_sum(&fs_info->stats_read_blocks);
6031 min_reads_per_dev = READ_ONCE(fs_info->fs_devices->rr_min_contig_read) >>
6032 fs_info->sectorsize_bits;
6033
6034 for (int index = 0, i = first; i < first + num_stripes; i++) {
6035 stripes[index].devid = map->stripes[i].dev->devid;
6036 stripes[index].num = i;
6037 index++;
6038 }
6039 sort(stripes, num_stripes, sizeof(struct stripe_mirror),
6040 btrfs_cmp_devid, NULL);
6041
6042 read_cycle = total_reads / min_reads_per_dev;
6043 return stripes[read_cycle % num_stripes].num;
6044 }
6045 #endif
6046
find_live_mirror(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map,int first,int dev_replace_is_ongoing)6047 static int find_live_mirror(struct btrfs_fs_info *fs_info,
6048 struct btrfs_chunk_map *map, int first,
6049 int dev_replace_is_ongoing)
6050 {
6051 const enum btrfs_read_policy policy = READ_ONCE(fs_info->fs_devices->read_policy);
6052 int i;
6053 int num_stripes;
6054 int preferred_mirror;
6055 int tolerance;
6056 struct btrfs_device *srcdev;
6057
6058 ASSERT((map->type &
6059 (BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10)));
6060
6061 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
6062 num_stripes = map->sub_stripes;
6063 else
6064 num_stripes = map->num_stripes;
6065
6066 switch (policy) {
6067 default:
6068 /* Shouldn't happen, just warn and use pid instead of failing */
6069 btrfs_warn_rl(fs_info, "unknown read_policy type %u, reset to pid",
6070 policy);
6071 WRITE_ONCE(fs_info->fs_devices->read_policy, BTRFS_READ_POLICY_PID);
6072 fallthrough;
6073 case BTRFS_READ_POLICY_PID:
6074 preferred_mirror = first + (current->pid % num_stripes);
6075 break;
6076 #ifdef CONFIG_BTRFS_EXPERIMENTAL
6077 case BTRFS_READ_POLICY_RR:
6078 preferred_mirror = btrfs_read_rr(map, first, num_stripes);
6079 break;
6080 case BTRFS_READ_POLICY_DEVID:
6081 preferred_mirror = btrfs_read_preferred(map, first, num_stripes);
6082 break;
6083 #endif
6084 }
6085
6086 if (dev_replace_is_ongoing &&
6087 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
6088 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
6089 srcdev = fs_info->dev_replace.srcdev;
6090 else
6091 srcdev = NULL;
6092
6093 /*
6094 * try to avoid the drive that is the source drive for a
6095 * dev-replace procedure, only choose it if no other non-missing
6096 * mirror is available
6097 */
6098 for (tolerance = 0; tolerance < 2; tolerance++) {
6099 if (map->stripes[preferred_mirror].dev->bdev &&
6100 (tolerance || map->stripes[preferred_mirror].dev != srcdev))
6101 return preferred_mirror;
6102 for (i = first; i < first + num_stripes; i++) {
6103 if (map->stripes[i].dev->bdev &&
6104 (tolerance || map->stripes[i].dev != srcdev))
6105 return i;
6106 }
6107 }
6108
6109 /* we couldn't find one that doesn't fail. Just return something
6110 * and the io error handling code will clean up eventually
6111 */
6112 return preferred_mirror;
6113 }
6114
6115 EXPORT_FOR_TESTS
alloc_btrfs_io_context(struct btrfs_fs_info * fs_info,u64 logical,u16 total_stripes)6116 struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
6117 u64 logical, u16 total_stripes)
6118 {
6119 struct btrfs_io_context *bioc;
6120
6121 bioc = kzalloc(
6122 /* The size of btrfs_io_context */
6123 sizeof(struct btrfs_io_context) +
6124 /* Plus the variable array for the stripes */
6125 sizeof(struct btrfs_io_stripe) * (total_stripes),
6126 GFP_NOFS);
6127
6128 if (!bioc)
6129 return NULL;
6130
6131 refcount_set(&bioc->refs, 1);
6132
6133 bioc->fs_info = fs_info;
6134 bioc->replace_stripe_src = -1;
6135 bioc->full_stripe_logical = (u64)-1;
6136 bioc->logical = logical;
6137
6138 return bioc;
6139 }
6140
btrfs_get_bioc(struct btrfs_io_context * bioc)6141 void btrfs_get_bioc(struct btrfs_io_context *bioc)
6142 {
6143 WARN_ON(!refcount_read(&bioc->refs));
6144 refcount_inc(&bioc->refs);
6145 }
6146
btrfs_put_bioc(struct btrfs_io_context * bioc)6147 void btrfs_put_bioc(struct btrfs_io_context *bioc)
6148 {
6149 if (!bioc)
6150 return;
6151 if (refcount_dec_and_test(&bioc->refs))
6152 kfree(bioc);
6153 }
6154
6155 /*
6156 * Please note that, discard won't be sent to target device of device
6157 * replace.
6158 */
btrfs_map_discard(struct btrfs_fs_info * fs_info,u64 logical,u64 * length_ret,u32 * num_stripes)6159 struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
6160 u64 logical, u64 *length_ret,
6161 u32 *num_stripes)
6162 {
6163 struct btrfs_chunk_map *map;
6164 struct btrfs_discard_stripe *stripes;
6165 u64 length = *length_ret;
6166 u64 offset;
6167 u32 stripe_nr;
6168 u32 stripe_nr_end;
6169 u32 stripe_cnt;
6170 u64 stripe_end_offset;
6171 u64 stripe_offset;
6172 u32 stripe_index;
6173 u32 factor = 0;
6174 u32 sub_stripes = 0;
6175 u32 stripes_per_dev = 0;
6176 u32 remaining_stripes = 0;
6177 u32 last_stripe = 0;
6178 int ret;
6179 int i;
6180
6181 map = btrfs_get_chunk_map(fs_info, logical, length);
6182 if (IS_ERR(map))
6183 return ERR_CAST(map);
6184
6185 /* we don't discard raid56 yet */
6186 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
6187 ret = -EOPNOTSUPP;
6188 goto out_free_map;
6189 }
6190
6191 offset = logical - map->start;
6192 length = min_t(u64, map->start + map->chunk_len - logical, length);
6193 *length_ret = length;
6194
6195 /*
6196 * stripe_nr counts the total number of stripes we have to stride
6197 * to get to this block
6198 */
6199 stripe_nr = offset >> BTRFS_STRIPE_LEN_SHIFT;
6200
6201 /* stripe_offset is the offset of this block in its stripe */
6202 stripe_offset = offset - btrfs_stripe_nr_to_offset(stripe_nr);
6203
6204 stripe_nr_end = round_up(offset + length, BTRFS_STRIPE_LEN) >>
6205 BTRFS_STRIPE_LEN_SHIFT;
6206 stripe_cnt = stripe_nr_end - stripe_nr;
6207 stripe_end_offset = btrfs_stripe_nr_to_offset(stripe_nr_end) -
6208 (offset + length);
6209 /*
6210 * after this, stripe_nr is the number of stripes on this
6211 * device we have to walk to find the data, and stripe_index is
6212 * the number of our device in the stripe array
6213 */
6214 *num_stripes = 1;
6215 stripe_index = 0;
6216 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
6217 BTRFS_BLOCK_GROUP_RAID10)) {
6218 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
6219 sub_stripes = 1;
6220 else
6221 sub_stripes = map->sub_stripes;
6222
6223 factor = map->num_stripes / sub_stripes;
6224 *num_stripes = min_t(u64, map->num_stripes,
6225 sub_stripes * stripe_cnt);
6226 stripe_index = stripe_nr % factor;
6227 stripe_nr /= factor;
6228 stripe_index *= sub_stripes;
6229
6230 remaining_stripes = stripe_cnt % factor;
6231 stripes_per_dev = stripe_cnt / factor;
6232 last_stripe = ((stripe_nr_end - 1) % factor) * sub_stripes;
6233 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID1_MASK |
6234 BTRFS_BLOCK_GROUP_DUP)) {
6235 *num_stripes = map->num_stripes;
6236 } else {
6237 stripe_index = stripe_nr % map->num_stripes;
6238 stripe_nr /= map->num_stripes;
6239 }
6240
6241 stripes = kcalloc(*num_stripes, sizeof(*stripes), GFP_NOFS);
6242 if (!stripes) {
6243 ret = -ENOMEM;
6244 goto out_free_map;
6245 }
6246
6247 for (i = 0; i < *num_stripes; i++) {
6248 stripes[i].physical =
6249 map->stripes[stripe_index].physical +
6250 stripe_offset + btrfs_stripe_nr_to_offset(stripe_nr);
6251 stripes[i].dev = map->stripes[stripe_index].dev;
6252
6253 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
6254 BTRFS_BLOCK_GROUP_RAID10)) {
6255 stripes[i].length = btrfs_stripe_nr_to_offset(stripes_per_dev);
6256
6257 if (i / sub_stripes < remaining_stripes)
6258 stripes[i].length += BTRFS_STRIPE_LEN;
6259
6260 /*
6261 * Special for the first stripe and
6262 * the last stripe:
6263 *
6264 * |-------|...|-------|
6265 * |----------|
6266 * off end_off
6267 */
6268 if (i < sub_stripes)
6269 stripes[i].length -= stripe_offset;
6270
6271 if (stripe_index >= last_stripe &&
6272 stripe_index <= (last_stripe +
6273 sub_stripes - 1))
6274 stripes[i].length -= stripe_end_offset;
6275
6276 if (i == sub_stripes - 1)
6277 stripe_offset = 0;
6278 } else {
6279 stripes[i].length = length;
6280 }
6281
6282 stripe_index++;
6283 if (stripe_index == map->num_stripes) {
6284 stripe_index = 0;
6285 stripe_nr++;
6286 }
6287 }
6288
6289 btrfs_free_chunk_map(map);
6290 return stripes;
6291 out_free_map:
6292 btrfs_free_chunk_map(map);
6293 return ERR_PTR(ret);
6294 }
6295
is_block_group_to_copy(struct btrfs_fs_info * fs_info,u64 logical)6296 static bool is_block_group_to_copy(struct btrfs_fs_info *fs_info, u64 logical)
6297 {
6298 struct btrfs_block_group *cache;
6299 bool ret;
6300
6301 /* Non zoned filesystem does not use "to_copy" flag */
6302 if (!btrfs_is_zoned(fs_info))
6303 return false;
6304
6305 cache = btrfs_lookup_block_group(fs_info, logical);
6306
6307 ret = test_bit(BLOCK_GROUP_FLAG_TO_COPY, &cache->runtime_flags);
6308
6309 btrfs_put_block_group(cache);
6310 return ret;
6311 }
6312
handle_ops_on_dev_replace(struct btrfs_io_context * bioc,struct btrfs_dev_replace * dev_replace,u64 logical,struct btrfs_io_geometry * io_geom)6313 static void handle_ops_on_dev_replace(struct btrfs_io_context *bioc,
6314 struct btrfs_dev_replace *dev_replace,
6315 u64 logical,
6316 struct btrfs_io_geometry *io_geom)
6317 {
6318 u64 srcdev_devid = dev_replace->srcdev->devid;
6319 /*
6320 * At this stage, num_stripes is still the real number of stripes,
6321 * excluding the duplicated stripes.
6322 */
6323 int num_stripes = io_geom->num_stripes;
6324 int max_errors = io_geom->max_errors;
6325 int nr_extra_stripes = 0;
6326 int i;
6327
6328 /*
6329 * A block group which has "to_copy" set will eventually be copied by
6330 * the dev-replace process. We can avoid cloning IO here.
6331 */
6332 if (is_block_group_to_copy(dev_replace->srcdev->fs_info, logical))
6333 return;
6334
6335 /*
6336 * Duplicate the write operations while the dev-replace procedure is
6337 * running. Since the copying of the old disk to the new disk takes
6338 * place at run time while the filesystem is mounted writable, the
6339 * regular write operations to the old disk have to be duplicated to go
6340 * to the new disk as well.
6341 *
6342 * Note that device->missing is handled by the caller, and that the
6343 * write to the old disk is already set up in the stripes array.
6344 */
6345 for (i = 0; i < num_stripes; i++) {
6346 struct btrfs_io_stripe *old = &bioc->stripes[i];
6347 struct btrfs_io_stripe *new = &bioc->stripes[num_stripes + nr_extra_stripes];
6348
6349 if (old->dev->devid != srcdev_devid)
6350 continue;
6351
6352 new->physical = old->physical;
6353 new->dev = dev_replace->tgtdev;
6354 if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK)
6355 bioc->replace_stripe_src = i;
6356 nr_extra_stripes++;
6357 }
6358
6359 /* We can only have at most 2 extra nr_stripes (for DUP). */
6360 ASSERT(nr_extra_stripes <= 2);
6361 /*
6362 * For GET_READ_MIRRORS, we can only return at most 1 extra stripe for
6363 * replace.
6364 * If we have 2 extra stripes, only choose the one with smaller physical.
6365 */
6366 if (io_geom->op == BTRFS_MAP_GET_READ_MIRRORS && nr_extra_stripes == 2) {
6367 struct btrfs_io_stripe *first = &bioc->stripes[num_stripes];
6368 struct btrfs_io_stripe *second = &bioc->stripes[num_stripes + 1];
6369
6370 /* Only DUP can have two extra stripes. */
6371 ASSERT(bioc->map_type & BTRFS_BLOCK_GROUP_DUP);
6372
6373 /*
6374 * Swap the last stripe stripes and reduce @nr_extra_stripes.
6375 * The extra stripe would still be there, but won't be accessed.
6376 */
6377 if (first->physical > second->physical) {
6378 swap(second->physical, first->physical);
6379 swap(second->dev, first->dev);
6380 nr_extra_stripes--;
6381 }
6382 }
6383
6384 io_geom->num_stripes = num_stripes + nr_extra_stripes;
6385 io_geom->max_errors = max_errors + nr_extra_stripes;
6386 bioc->replace_nr_stripes = nr_extra_stripes;
6387 }
6388
btrfs_max_io_len(struct btrfs_chunk_map * map,u64 offset,struct btrfs_io_geometry * io_geom)6389 static u64 btrfs_max_io_len(struct btrfs_chunk_map *map, u64 offset,
6390 struct btrfs_io_geometry *io_geom)
6391 {
6392 /*
6393 * Stripe_nr is the stripe where this block falls. stripe_offset is
6394 * the offset of this block in its stripe.
6395 */
6396 io_geom->stripe_offset = offset & BTRFS_STRIPE_LEN_MASK;
6397 io_geom->stripe_nr = offset >> BTRFS_STRIPE_LEN_SHIFT;
6398 ASSERT(io_geom->stripe_offset < U32_MAX);
6399
6400 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
6401 unsigned long full_stripe_len =
6402 btrfs_stripe_nr_to_offset(nr_data_stripes(map));
6403
6404 /*
6405 * For full stripe start, we use previously calculated
6406 * @stripe_nr. Align it to nr_data_stripes, then multiply with
6407 * STRIPE_LEN.
6408 *
6409 * By this we can avoid u64 division completely. And we have
6410 * to go rounddown(), not round_down(), as nr_data_stripes is
6411 * not ensured to be power of 2.
6412 */
6413 io_geom->raid56_full_stripe_start = btrfs_stripe_nr_to_offset(
6414 rounddown(io_geom->stripe_nr, nr_data_stripes(map)));
6415
6416 ASSERT(io_geom->raid56_full_stripe_start + full_stripe_len > offset);
6417 ASSERT(io_geom->raid56_full_stripe_start <= offset);
6418 /*
6419 * For writes to RAID56, allow to write a full stripe set, but
6420 * no straddling of stripe sets.
6421 */
6422 if (io_geom->op == BTRFS_MAP_WRITE)
6423 return full_stripe_len - (offset - io_geom->raid56_full_stripe_start);
6424 }
6425
6426 /*
6427 * For other RAID types and for RAID56 reads, allow a single stripe (on
6428 * a single disk).
6429 */
6430 if (map->type & BTRFS_BLOCK_GROUP_STRIPE_MASK)
6431 return BTRFS_STRIPE_LEN - io_geom->stripe_offset;
6432 return U64_MAX;
6433 }
6434
set_io_stripe(struct btrfs_fs_info * fs_info,u64 logical,u64 * length,struct btrfs_io_stripe * dst,struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6435 static int set_io_stripe(struct btrfs_fs_info *fs_info, u64 logical,
6436 u64 *length, struct btrfs_io_stripe *dst,
6437 struct btrfs_chunk_map *map,
6438 struct btrfs_io_geometry *io_geom)
6439 {
6440 dst->dev = map->stripes[io_geom->stripe_index].dev;
6441
6442 if (io_geom->op == BTRFS_MAP_READ && io_geom->use_rst)
6443 return btrfs_get_raid_extent_offset(fs_info, logical, length,
6444 map->type,
6445 io_geom->stripe_index, dst);
6446
6447 dst->physical = map->stripes[io_geom->stripe_index].physical +
6448 io_geom->stripe_offset +
6449 btrfs_stripe_nr_to_offset(io_geom->stripe_nr);
6450 return 0;
6451 }
6452
is_single_device_io(struct btrfs_fs_info * fs_info,const struct btrfs_io_stripe * smap,const struct btrfs_chunk_map * map,int num_alloc_stripes,struct btrfs_io_geometry * io_geom)6453 static bool is_single_device_io(struct btrfs_fs_info *fs_info,
6454 const struct btrfs_io_stripe *smap,
6455 const struct btrfs_chunk_map *map,
6456 int num_alloc_stripes,
6457 struct btrfs_io_geometry *io_geom)
6458 {
6459 if (!smap)
6460 return false;
6461
6462 if (num_alloc_stripes != 1)
6463 return false;
6464
6465 if (io_geom->use_rst && io_geom->op != BTRFS_MAP_READ)
6466 return false;
6467
6468 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) && io_geom->mirror_num > 1)
6469 return false;
6470
6471 return true;
6472 }
6473
map_blocks_raid0(const struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6474 static void map_blocks_raid0(const struct btrfs_chunk_map *map,
6475 struct btrfs_io_geometry *io_geom)
6476 {
6477 io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes;
6478 io_geom->stripe_nr /= map->num_stripes;
6479 if (io_geom->op == BTRFS_MAP_READ)
6480 io_geom->mirror_num = 1;
6481 }
6482
map_blocks_raid1(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom,bool dev_replace_is_ongoing)6483 static void map_blocks_raid1(struct btrfs_fs_info *fs_info,
6484 struct btrfs_chunk_map *map,
6485 struct btrfs_io_geometry *io_geom,
6486 bool dev_replace_is_ongoing)
6487 {
6488 if (io_geom->op != BTRFS_MAP_READ) {
6489 io_geom->num_stripes = map->num_stripes;
6490 return;
6491 }
6492
6493 if (io_geom->mirror_num) {
6494 io_geom->stripe_index = io_geom->mirror_num - 1;
6495 return;
6496 }
6497
6498 io_geom->stripe_index = find_live_mirror(fs_info, map, 0,
6499 dev_replace_is_ongoing);
6500 io_geom->mirror_num = io_geom->stripe_index + 1;
6501 }
6502
map_blocks_dup(const struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6503 static void map_blocks_dup(const struct btrfs_chunk_map *map,
6504 struct btrfs_io_geometry *io_geom)
6505 {
6506 if (io_geom->op != BTRFS_MAP_READ) {
6507 io_geom->num_stripes = map->num_stripes;
6508 return;
6509 }
6510
6511 if (io_geom->mirror_num) {
6512 io_geom->stripe_index = io_geom->mirror_num - 1;
6513 return;
6514 }
6515
6516 io_geom->mirror_num = 1;
6517 }
6518
map_blocks_raid10(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom,bool dev_replace_is_ongoing)6519 static void map_blocks_raid10(struct btrfs_fs_info *fs_info,
6520 struct btrfs_chunk_map *map,
6521 struct btrfs_io_geometry *io_geom,
6522 bool dev_replace_is_ongoing)
6523 {
6524 u32 factor = map->num_stripes / map->sub_stripes;
6525 int old_stripe_index;
6526
6527 io_geom->stripe_index = (io_geom->stripe_nr % factor) * map->sub_stripes;
6528 io_geom->stripe_nr /= factor;
6529
6530 if (io_geom->op != BTRFS_MAP_READ) {
6531 io_geom->num_stripes = map->sub_stripes;
6532 return;
6533 }
6534
6535 if (io_geom->mirror_num) {
6536 io_geom->stripe_index += io_geom->mirror_num - 1;
6537 return;
6538 }
6539
6540 old_stripe_index = io_geom->stripe_index;
6541 io_geom->stripe_index = find_live_mirror(fs_info, map,
6542 io_geom->stripe_index,
6543 dev_replace_is_ongoing);
6544 io_geom->mirror_num = io_geom->stripe_index - old_stripe_index + 1;
6545 }
6546
map_blocks_raid56_write(struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom,u64 logical,u64 * length)6547 static void map_blocks_raid56_write(struct btrfs_chunk_map *map,
6548 struct btrfs_io_geometry *io_geom,
6549 u64 logical, u64 *length)
6550 {
6551 int data_stripes = nr_data_stripes(map);
6552
6553 /*
6554 * Needs full stripe mapping.
6555 *
6556 * Push stripe_nr back to the start of the full stripe For those cases
6557 * needing a full stripe, @stripe_nr is the full stripe number.
6558 *
6559 * Originally we go raid56_full_stripe_start / full_stripe_len, but
6560 * that can be expensive. Here we just divide @stripe_nr with
6561 * @data_stripes.
6562 */
6563 io_geom->stripe_nr /= data_stripes;
6564
6565 /* RAID[56] write or recovery. Return all stripes */
6566 io_geom->num_stripes = map->num_stripes;
6567 io_geom->max_errors = btrfs_chunk_max_errors(map);
6568
6569 /* Return the length to the full stripe end. */
6570 *length = min(logical + *length,
6571 io_geom->raid56_full_stripe_start + map->start +
6572 btrfs_stripe_nr_to_offset(data_stripes)) -
6573 logical;
6574 io_geom->stripe_index = 0;
6575 io_geom->stripe_offset = 0;
6576 }
6577
map_blocks_raid56_read(struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6578 static void map_blocks_raid56_read(struct btrfs_chunk_map *map,
6579 struct btrfs_io_geometry *io_geom)
6580 {
6581 int data_stripes = nr_data_stripes(map);
6582
6583 ASSERT(io_geom->mirror_num <= 1);
6584 /* Just grab the data stripe directly. */
6585 io_geom->stripe_index = io_geom->stripe_nr % data_stripes;
6586 io_geom->stripe_nr /= data_stripes;
6587
6588 /* We distribute the parity blocks across stripes. */
6589 io_geom->stripe_index =
6590 (io_geom->stripe_nr + io_geom->stripe_index) % map->num_stripes;
6591
6592 if (io_geom->op == BTRFS_MAP_READ && io_geom->mirror_num < 1)
6593 io_geom->mirror_num = 1;
6594 }
6595
map_blocks_single(const struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6596 static void map_blocks_single(const struct btrfs_chunk_map *map,
6597 struct btrfs_io_geometry *io_geom)
6598 {
6599 io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes;
6600 io_geom->stripe_nr /= map->num_stripes;
6601 io_geom->mirror_num = io_geom->stripe_index + 1;
6602 }
6603
6604 /*
6605 * Map one logical range to one or more physical ranges.
6606 *
6607 * @length: (Mandatory) mapped length of this run.
6608 * One logical range can be split into different segments
6609 * due to factors like zones and RAID0/5/6/10 stripe
6610 * boundaries.
6611 *
6612 * @bioc_ret: (Mandatory) returned btrfs_io_context structure.
6613 * which has one or more physical ranges (btrfs_io_stripe)
6614 * recorded inside.
6615 * Caller should call btrfs_put_bioc() to free it after use.
6616 *
6617 * @smap: (Optional) single physical range optimization.
6618 * If the map request can be fulfilled by one single
6619 * physical range, and this is parameter is not NULL,
6620 * then @bioc_ret would be NULL, and @smap would be
6621 * updated.
6622 *
6623 * @mirror_num_ret: (Mandatory) returned mirror number if the original
6624 * value is 0.
6625 *
6626 * Mirror number 0 means to choose any live mirrors.
6627 *
6628 * For non-RAID56 profiles, non-zero mirror_num means
6629 * the Nth mirror. (e.g. mirror_num 1 means the first
6630 * copy).
6631 *
6632 * For RAID56 profile, mirror 1 means rebuild from P and
6633 * the remaining data stripes.
6634 *
6635 * For RAID6 profile, mirror > 2 means mark another
6636 * data/P stripe error and rebuild from the remaining
6637 * stripes..
6638 */
btrfs_map_block(struct btrfs_fs_info * fs_info,enum btrfs_map_op op,u64 logical,u64 * length,struct btrfs_io_context ** bioc_ret,struct btrfs_io_stripe * smap,int * mirror_num_ret)6639 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
6640 u64 logical, u64 *length,
6641 struct btrfs_io_context **bioc_ret,
6642 struct btrfs_io_stripe *smap, int *mirror_num_ret)
6643 {
6644 struct btrfs_chunk_map *map;
6645 struct btrfs_io_geometry io_geom = { 0 };
6646 u64 map_offset;
6647 int ret = 0;
6648 int num_copies;
6649 struct btrfs_io_context *bioc = NULL;
6650 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
6651 int dev_replace_is_ongoing = 0;
6652 u16 num_alloc_stripes;
6653 u64 max_len;
6654
6655 ASSERT(bioc_ret);
6656
6657 io_geom.mirror_num = (mirror_num_ret ? *mirror_num_ret : 0);
6658 io_geom.num_stripes = 1;
6659 io_geom.stripe_index = 0;
6660 io_geom.op = op;
6661
6662 map = btrfs_get_chunk_map(fs_info, logical, *length);
6663 if (IS_ERR(map))
6664 return PTR_ERR(map);
6665
6666 num_copies = btrfs_chunk_map_num_copies(map);
6667 if (io_geom.mirror_num > num_copies)
6668 return -EINVAL;
6669
6670 map_offset = logical - map->start;
6671 io_geom.raid56_full_stripe_start = (u64)-1;
6672 max_len = btrfs_max_io_len(map, map_offset, &io_geom);
6673 *length = min_t(u64, map->chunk_len - map_offset, max_len);
6674 io_geom.use_rst = btrfs_need_stripe_tree_update(fs_info, map->type);
6675
6676 if (dev_replace->replace_task != current)
6677 down_read(&dev_replace->rwsem);
6678
6679 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
6680 /*
6681 * Hold the semaphore for read during the whole operation, write is
6682 * requested at commit time but must wait.
6683 */
6684 if (!dev_replace_is_ongoing && dev_replace->replace_task != current)
6685 up_read(&dev_replace->rwsem);
6686
6687 switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
6688 case BTRFS_BLOCK_GROUP_RAID0:
6689 map_blocks_raid0(map, &io_geom);
6690 break;
6691 case BTRFS_BLOCK_GROUP_RAID1:
6692 case BTRFS_BLOCK_GROUP_RAID1C3:
6693 case BTRFS_BLOCK_GROUP_RAID1C4:
6694 map_blocks_raid1(fs_info, map, &io_geom, dev_replace_is_ongoing);
6695 break;
6696 case BTRFS_BLOCK_GROUP_DUP:
6697 map_blocks_dup(map, &io_geom);
6698 break;
6699 case BTRFS_BLOCK_GROUP_RAID10:
6700 map_blocks_raid10(fs_info, map, &io_geom, dev_replace_is_ongoing);
6701 break;
6702 case BTRFS_BLOCK_GROUP_RAID5:
6703 case BTRFS_BLOCK_GROUP_RAID6:
6704 if (op != BTRFS_MAP_READ || io_geom.mirror_num > 1)
6705 map_blocks_raid56_write(map, &io_geom, logical, length);
6706 else
6707 map_blocks_raid56_read(map, &io_geom);
6708 break;
6709 default:
6710 /*
6711 * After this, stripe_nr is the number of stripes on this
6712 * device we have to walk to find the data, and stripe_index is
6713 * the number of our device in the stripe array
6714 */
6715 map_blocks_single(map, &io_geom);
6716 break;
6717 }
6718 if (io_geom.stripe_index >= map->num_stripes) {
6719 btrfs_crit(fs_info,
6720 "stripe index math went horribly wrong, got stripe_index=%u, num_stripes=%u",
6721 io_geom.stripe_index, map->num_stripes);
6722 ret = -EINVAL;
6723 goto out;
6724 }
6725
6726 num_alloc_stripes = io_geom.num_stripes;
6727 if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL &&
6728 op != BTRFS_MAP_READ)
6729 /*
6730 * For replace case, we need to add extra stripes for extra
6731 * duplicated stripes.
6732 *
6733 * For both WRITE and GET_READ_MIRRORS, we may have at most
6734 * 2 more stripes (DUP types, otherwise 1).
6735 */
6736 num_alloc_stripes += 2;
6737
6738 /*
6739 * If this I/O maps to a single device, try to return the device and
6740 * physical block information on the stack instead of allocating an
6741 * I/O context structure.
6742 */
6743 if (is_single_device_io(fs_info, smap, map, num_alloc_stripes, &io_geom)) {
6744 ret = set_io_stripe(fs_info, logical, length, smap, map, &io_geom);
6745 if (mirror_num_ret)
6746 *mirror_num_ret = io_geom.mirror_num;
6747 *bioc_ret = NULL;
6748 goto out;
6749 }
6750
6751 bioc = alloc_btrfs_io_context(fs_info, logical, num_alloc_stripes);
6752 if (!bioc) {
6753 ret = -ENOMEM;
6754 goto out;
6755 }
6756 bioc->map_type = map->type;
6757 bioc->use_rst = io_geom.use_rst;
6758
6759 /*
6760 * For RAID56 full map, we need to make sure the stripes[] follows the
6761 * rule that data stripes are all ordered, then followed with P and Q
6762 * (if we have).
6763 *
6764 * It's still mostly the same as other profiles, just with extra rotation.
6765 */
6766 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
6767 (op != BTRFS_MAP_READ || io_geom.mirror_num > 1)) {
6768 /*
6769 * For RAID56 @stripe_nr is already the number of full stripes
6770 * before us, which is also the rotation value (needs to modulo
6771 * with num_stripes).
6772 *
6773 * In this case, we just add @stripe_nr with @i, then do the
6774 * modulo, to reduce one modulo call.
6775 */
6776 bioc->full_stripe_logical = map->start +
6777 btrfs_stripe_nr_to_offset(io_geom.stripe_nr *
6778 nr_data_stripes(map));
6779 for (int i = 0; i < io_geom.num_stripes; i++) {
6780 struct btrfs_io_stripe *dst = &bioc->stripes[i];
6781 u32 stripe_index;
6782
6783 stripe_index = (i + io_geom.stripe_nr) % io_geom.num_stripes;
6784 dst->dev = map->stripes[stripe_index].dev;
6785 dst->physical =
6786 map->stripes[stripe_index].physical +
6787 io_geom.stripe_offset +
6788 btrfs_stripe_nr_to_offset(io_geom.stripe_nr);
6789 }
6790 } else {
6791 /*
6792 * For all other non-RAID56 profiles, just copy the target
6793 * stripe into the bioc.
6794 */
6795 for (int i = 0; i < io_geom.num_stripes; i++) {
6796 ret = set_io_stripe(fs_info, logical, length,
6797 &bioc->stripes[i], map, &io_geom);
6798 if (ret < 0)
6799 break;
6800 io_geom.stripe_index++;
6801 }
6802 }
6803
6804 if (ret) {
6805 *bioc_ret = NULL;
6806 btrfs_put_bioc(bioc);
6807 goto out;
6808 }
6809
6810 if (op != BTRFS_MAP_READ)
6811 io_geom.max_errors = btrfs_chunk_max_errors(map);
6812
6813 if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL &&
6814 op != BTRFS_MAP_READ) {
6815 handle_ops_on_dev_replace(bioc, dev_replace, logical, &io_geom);
6816 }
6817
6818 *bioc_ret = bioc;
6819 bioc->num_stripes = io_geom.num_stripes;
6820 bioc->max_errors = io_geom.max_errors;
6821 bioc->mirror_num = io_geom.mirror_num;
6822
6823 out:
6824 if (dev_replace_is_ongoing && dev_replace->replace_task != current) {
6825 lockdep_assert_held(&dev_replace->rwsem);
6826 /* Unlock and let waiting writers proceed */
6827 up_read(&dev_replace->rwsem);
6828 }
6829 btrfs_free_chunk_map(map);
6830 return ret;
6831 }
6832
dev_args_match_fs_devices(const struct btrfs_dev_lookup_args * args,const struct btrfs_fs_devices * fs_devices)6833 static bool dev_args_match_fs_devices(const struct btrfs_dev_lookup_args *args,
6834 const struct btrfs_fs_devices *fs_devices)
6835 {
6836 if (args->fsid == NULL)
6837 return true;
6838 if (memcmp(fs_devices->metadata_uuid, args->fsid, BTRFS_FSID_SIZE) == 0)
6839 return true;
6840 return false;
6841 }
6842
dev_args_match_device(const struct btrfs_dev_lookup_args * args,const struct btrfs_device * device)6843 static bool dev_args_match_device(const struct btrfs_dev_lookup_args *args,
6844 const struct btrfs_device *device)
6845 {
6846 if (args->missing) {
6847 if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state) &&
6848 !device->bdev)
6849 return true;
6850 return false;
6851 }
6852
6853 if (device->devid != args->devid)
6854 return false;
6855 if (args->uuid && memcmp(device->uuid, args->uuid, BTRFS_UUID_SIZE) != 0)
6856 return false;
6857 return true;
6858 }
6859
6860 /*
6861 * Find a device specified by @devid or @uuid in the list of @fs_devices, or
6862 * return NULL.
6863 *
6864 * If devid and uuid are both specified, the match must be exact, otherwise
6865 * only devid is used.
6866 */
btrfs_find_device(const struct btrfs_fs_devices * fs_devices,const struct btrfs_dev_lookup_args * args)6867 struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
6868 const struct btrfs_dev_lookup_args *args)
6869 {
6870 struct btrfs_device *device;
6871 struct btrfs_fs_devices *seed_devs;
6872
6873 if (dev_args_match_fs_devices(args, fs_devices)) {
6874 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6875 if (dev_args_match_device(args, device))
6876 return device;
6877 }
6878 }
6879
6880 list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
6881 if (!dev_args_match_fs_devices(args, seed_devs))
6882 continue;
6883 list_for_each_entry(device, &seed_devs->devices, dev_list) {
6884 if (dev_args_match_device(args, device))
6885 return device;
6886 }
6887 }
6888
6889 return NULL;
6890 }
6891
add_missing_dev(struct btrfs_fs_devices * fs_devices,u64 devid,u8 * dev_uuid)6892 static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices,
6893 u64 devid, u8 *dev_uuid)
6894 {
6895 struct btrfs_device *device;
6896 unsigned int nofs_flag;
6897
6898 /*
6899 * We call this under the chunk_mutex, so we want to use NOFS for this
6900 * allocation, however we don't want to change btrfs_alloc_device() to
6901 * always do NOFS because we use it in a lot of other GFP_KERNEL safe
6902 * places.
6903 */
6904
6905 nofs_flag = memalloc_nofs_save();
6906 device = btrfs_alloc_device(NULL, &devid, dev_uuid, NULL);
6907 memalloc_nofs_restore(nofs_flag);
6908 if (IS_ERR(device))
6909 return device;
6910
6911 list_add(&device->dev_list, &fs_devices->devices);
6912 device->fs_devices = fs_devices;
6913 fs_devices->num_devices++;
6914
6915 set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
6916 fs_devices->missing_devices++;
6917
6918 return device;
6919 }
6920
6921 /*
6922 * Allocate new device struct, set up devid and UUID.
6923 *
6924 * @fs_info: used only for generating a new devid, can be NULL if
6925 * devid is provided (i.e. @devid != NULL).
6926 * @devid: a pointer to devid for this device. If NULL a new devid
6927 * is generated.
6928 * @uuid: a pointer to UUID for this device. If NULL a new UUID
6929 * is generated.
6930 * @path: a pointer to device path if available, NULL otherwise.
6931 *
6932 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
6933 * on error. Returned struct is not linked onto any lists and must be
6934 * destroyed with btrfs_free_device.
6935 */
btrfs_alloc_device(struct btrfs_fs_info * fs_info,const u64 * devid,const u8 * uuid,const char * path)6936 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
6937 const u64 *devid, const u8 *uuid,
6938 const char *path)
6939 {
6940 struct btrfs_device *dev;
6941 u64 tmp;
6942
6943 if (WARN_ON(!devid && !fs_info))
6944 return ERR_PTR(-EINVAL);
6945
6946 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
6947 if (!dev)
6948 return ERR_PTR(-ENOMEM);
6949
6950 INIT_LIST_HEAD(&dev->dev_list);
6951 INIT_LIST_HEAD(&dev->dev_alloc_list);
6952 INIT_LIST_HEAD(&dev->post_commit_list);
6953
6954 atomic_set(&dev->dev_stats_ccnt, 0);
6955 btrfs_device_data_ordered_init(dev);
6956 extent_io_tree_init(fs_info, &dev->alloc_state, IO_TREE_DEVICE_ALLOC_STATE);
6957
6958 if (devid)
6959 tmp = *devid;
6960 else {
6961 int ret;
6962
6963 ret = find_next_devid(fs_info, &tmp);
6964 if (ret) {
6965 btrfs_free_device(dev);
6966 return ERR_PTR(ret);
6967 }
6968 }
6969 dev->devid = tmp;
6970
6971 if (uuid)
6972 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
6973 else
6974 generate_random_uuid(dev->uuid);
6975
6976 if (path) {
6977 struct rcu_string *name;
6978
6979 name = rcu_string_strdup(path, GFP_KERNEL);
6980 if (!name) {
6981 btrfs_free_device(dev);
6982 return ERR_PTR(-ENOMEM);
6983 }
6984 rcu_assign_pointer(dev->name, name);
6985 }
6986
6987 return dev;
6988 }
6989
btrfs_report_missing_device(struct btrfs_fs_info * fs_info,u64 devid,u8 * uuid,bool error)6990 static void btrfs_report_missing_device(struct btrfs_fs_info *fs_info,
6991 u64 devid, u8 *uuid, bool error)
6992 {
6993 if (error)
6994 btrfs_err_rl(fs_info, "devid %llu uuid %pU is missing",
6995 devid, uuid);
6996 else
6997 btrfs_warn_rl(fs_info, "devid %llu uuid %pU is missing",
6998 devid, uuid);
6999 }
7000
btrfs_calc_stripe_length(const struct btrfs_chunk_map * map)7001 u64 btrfs_calc_stripe_length(const struct btrfs_chunk_map *map)
7002 {
7003 const int data_stripes = calc_data_stripes(map->type, map->num_stripes);
7004
7005 return div_u64(map->chunk_len, data_stripes);
7006 }
7007
7008 #if BITS_PER_LONG == 32
7009 /*
7010 * Due to page cache limit, metadata beyond BTRFS_32BIT_MAX_FILE_SIZE
7011 * can't be accessed on 32bit systems.
7012 *
7013 * This function do mount time check to reject the fs if it already has
7014 * metadata chunk beyond that limit.
7015 */
check_32bit_meta_chunk(struct btrfs_fs_info * fs_info,u64 logical,u64 length,u64 type)7016 static int check_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
7017 u64 logical, u64 length, u64 type)
7018 {
7019 if (!(type & BTRFS_BLOCK_GROUP_METADATA))
7020 return 0;
7021
7022 if (logical + length < MAX_LFS_FILESIZE)
7023 return 0;
7024
7025 btrfs_err_32bit_limit(fs_info);
7026 return -EOVERFLOW;
7027 }
7028
7029 /*
7030 * This is to give early warning for any metadata chunk reaching
7031 * BTRFS_32BIT_EARLY_WARN_THRESHOLD.
7032 * Although we can still access the metadata, it's not going to be possible
7033 * once the limit is reached.
7034 */
warn_32bit_meta_chunk(struct btrfs_fs_info * fs_info,u64 logical,u64 length,u64 type)7035 static void warn_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
7036 u64 logical, u64 length, u64 type)
7037 {
7038 if (!(type & BTRFS_BLOCK_GROUP_METADATA))
7039 return;
7040
7041 if (logical + length < BTRFS_32BIT_EARLY_WARN_THRESHOLD)
7042 return;
7043
7044 btrfs_warn_32bit_limit(fs_info);
7045 }
7046 #endif
7047
handle_missing_device(struct btrfs_fs_info * fs_info,u64 devid,u8 * uuid)7048 static struct btrfs_device *handle_missing_device(struct btrfs_fs_info *fs_info,
7049 u64 devid, u8 *uuid)
7050 {
7051 struct btrfs_device *dev;
7052
7053 if (!btrfs_test_opt(fs_info, DEGRADED)) {
7054 btrfs_report_missing_device(fs_info, devid, uuid, true);
7055 return ERR_PTR(-ENOENT);
7056 }
7057
7058 dev = add_missing_dev(fs_info->fs_devices, devid, uuid);
7059 if (IS_ERR(dev)) {
7060 btrfs_err(fs_info, "failed to init missing device %llu: %ld",
7061 devid, PTR_ERR(dev));
7062 return dev;
7063 }
7064 btrfs_report_missing_device(fs_info, devid, uuid, false);
7065
7066 return dev;
7067 }
7068
read_one_chunk(struct btrfs_key * key,struct extent_buffer * leaf,struct btrfs_chunk * chunk)7069 static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
7070 struct btrfs_chunk *chunk)
7071 {
7072 BTRFS_DEV_LOOKUP_ARGS(args);
7073 struct btrfs_fs_info *fs_info = leaf->fs_info;
7074 struct btrfs_chunk_map *map;
7075 u64 logical;
7076 u64 length;
7077 u64 devid;
7078 u64 type;
7079 u8 uuid[BTRFS_UUID_SIZE];
7080 int index;
7081 int num_stripes;
7082 int ret;
7083 int i;
7084
7085 logical = key->offset;
7086 length = btrfs_chunk_length(leaf, chunk);
7087 type = btrfs_chunk_type(leaf, chunk);
7088 index = btrfs_bg_flags_to_raid_index(type);
7089 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
7090
7091 #if BITS_PER_LONG == 32
7092 ret = check_32bit_meta_chunk(fs_info, logical, length, type);
7093 if (ret < 0)
7094 return ret;
7095 warn_32bit_meta_chunk(fs_info, logical, length, type);
7096 #endif
7097
7098 map = btrfs_find_chunk_map(fs_info, logical, 1);
7099
7100 /* already mapped? */
7101 if (map && map->start <= logical && map->start + map->chunk_len > logical) {
7102 btrfs_free_chunk_map(map);
7103 return 0;
7104 } else if (map) {
7105 btrfs_free_chunk_map(map);
7106 }
7107
7108 map = btrfs_alloc_chunk_map(num_stripes, GFP_NOFS);
7109 if (!map)
7110 return -ENOMEM;
7111
7112 map->start = logical;
7113 map->chunk_len = length;
7114 map->num_stripes = num_stripes;
7115 map->io_width = btrfs_chunk_io_width(leaf, chunk);
7116 map->io_align = btrfs_chunk_io_align(leaf, chunk);
7117 map->type = type;
7118 /*
7119 * We can't use the sub_stripes value, as for profiles other than
7120 * RAID10, they may have 0 as sub_stripes for filesystems created by
7121 * older mkfs (<v5.4).
7122 * In that case, it can cause divide-by-zero errors later.
7123 * Since currently sub_stripes is fixed for each profile, let's
7124 * use the trusted value instead.
7125 */
7126 map->sub_stripes = btrfs_raid_array[index].sub_stripes;
7127 map->verified_stripes = 0;
7128 map->stripe_size = btrfs_calc_stripe_length(map);
7129 for (i = 0; i < num_stripes; i++) {
7130 map->stripes[i].physical =
7131 btrfs_stripe_offset_nr(leaf, chunk, i);
7132 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
7133 args.devid = devid;
7134 read_extent_buffer(leaf, uuid, (unsigned long)
7135 btrfs_stripe_dev_uuid_nr(chunk, i),
7136 BTRFS_UUID_SIZE);
7137 args.uuid = uuid;
7138 map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices, &args);
7139 if (!map->stripes[i].dev) {
7140 map->stripes[i].dev = handle_missing_device(fs_info,
7141 devid, uuid);
7142 if (IS_ERR(map->stripes[i].dev)) {
7143 ret = PTR_ERR(map->stripes[i].dev);
7144 btrfs_free_chunk_map(map);
7145 return ret;
7146 }
7147 }
7148
7149 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
7150 &(map->stripes[i].dev->dev_state));
7151 }
7152
7153 ret = btrfs_add_chunk_map(fs_info, map);
7154 if (ret < 0) {
7155 btrfs_err(fs_info,
7156 "failed to add chunk map, start=%llu len=%llu: %d",
7157 map->start, map->chunk_len, ret);
7158 btrfs_free_chunk_map(map);
7159 }
7160
7161 return ret;
7162 }
7163
fill_device_from_item(struct extent_buffer * leaf,struct btrfs_dev_item * dev_item,struct btrfs_device * device)7164 static void fill_device_from_item(struct extent_buffer *leaf,
7165 struct btrfs_dev_item *dev_item,
7166 struct btrfs_device *device)
7167 {
7168 unsigned long ptr;
7169
7170 device->devid = btrfs_device_id(leaf, dev_item);
7171 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
7172 device->total_bytes = device->disk_total_bytes;
7173 device->commit_total_bytes = device->disk_total_bytes;
7174 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
7175 device->commit_bytes_used = device->bytes_used;
7176 device->type = btrfs_device_type(leaf, dev_item);
7177 device->io_align = btrfs_device_io_align(leaf, dev_item);
7178 device->io_width = btrfs_device_io_width(leaf, dev_item);
7179 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
7180 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
7181 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
7182
7183 ptr = btrfs_device_uuid(dev_item);
7184 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
7185 }
7186
open_seed_devices(struct btrfs_fs_info * fs_info,u8 * fsid)7187 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info,
7188 u8 *fsid)
7189 {
7190 struct btrfs_fs_devices *fs_devices;
7191 int ret;
7192
7193 lockdep_assert_held(&uuid_mutex);
7194 ASSERT(fsid);
7195
7196 /* This will match only for multi-device seed fs */
7197 list_for_each_entry(fs_devices, &fs_info->fs_devices->seed_list, seed_list)
7198 if (!memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE))
7199 return fs_devices;
7200
7201
7202 fs_devices = find_fsid(fsid, NULL);
7203 if (!fs_devices) {
7204 if (!btrfs_test_opt(fs_info, DEGRADED)) {
7205 btrfs_err(fs_info,
7206 "failed to find fsid %pU when attempting to open seed devices",
7207 fsid);
7208 return ERR_PTR(-ENOENT);
7209 }
7210
7211 fs_devices = alloc_fs_devices(fsid);
7212 if (IS_ERR(fs_devices))
7213 return fs_devices;
7214
7215 fs_devices->seeding = true;
7216 fs_devices->opened = 1;
7217 return fs_devices;
7218 }
7219
7220 /*
7221 * Upon first call for a seed fs fsid, just create a private copy of the
7222 * respective fs_devices and anchor it at fs_info->fs_devices->seed_list
7223 */
7224 fs_devices = clone_fs_devices(fs_devices);
7225 if (IS_ERR(fs_devices))
7226 return fs_devices;
7227
7228 ret = open_fs_devices(fs_devices, BLK_OPEN_READ, fs_info->bdev_holder);
7229 if (ret) {
7230 free_fs_devices(fs_devices);
7231 return ERR_PTR(ret);
7232 }
7233
7234 if (!fs_devices->seeding) {
7235 close_fs_devices(fs_devices);
7236 free_fs_devices(fs_devices);
7237 return ERR_PTR(-EINVAL);
7238 }
7239
7240 list_add(&fs_devices->seed_list, &fs_info->fs_devices->seed_list);
7241
7242 return fs_devices;
7243 }
7244
read_one_dev(struct extent_buffer * leaf,struct btrfs_dev_item * dev_item)7245 static int read_one_dev(struct extent_buffer *leaf,
7246 struct btrfs_dev_item *dev_item)
7247 {
7248 BTRFS_DEV_LOOKUP_ARGS(args);
7249 struct btrfs_fs_info *fs_info = leaf->fs_info;
7250 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7251 struct btrfs_device *device;
7252 u64 devid;
7253 int ret;
7254 u8 fs_uuid[BTRFS_FSID_SIZE];
7255 u8 dev_uuid[BTRFS_UUID_SIZE];
7256
7257 devid = btrfs_device_id(leaf, dev_item);
7258 args.devid = devid;
7259 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
7260 BTRFS_UUID_SIZE);
7261 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
7262 BTRFS_FSID_SIZE);
7263 args.uuid = dev_uuid;
7264 args.fsid = fs_uuid;
7265
7266 if (memcmp(fs_uuid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE)) {
7267 fs_devices = open_seed_devices(fs_info, fs_uuid);
7268 if (IS_ERR(fs_devices))
7269 return PTR_ERR(fs_devices);
7270 }
7271
7272 device = btrfs_find_device(fs_info->fs_devices, &args);
7273 if (!device) {
7274 if (!btrfs_test_opt(fs_info, DEGRADED)) {
7275 btrfs_report_missing_device(fs_info, devid,
7276 dev_uuid, true);
7277 return -ENOENT;
7278 }
7279
7280 device = add_missing_dev(fs_devices, devid, dev_uuid);
7281 if (IS_ERR(device)) {
7282 btrfs_err(fs_info,
7283 "failed to add missing dev %llu: %ld",
7284 devid, PTR_ERR(device));
7285 return PTR_ERR(device);
7286 }
7287 btrfs_report_missing_device(fs_info, devid, dev_uuid, false);
7288 } else {
7289 if (!device->bdev) {
7290 if (!btrfs_test_opt(fs_info, DEGRADED)) {
7291 btrfs_report_missing_device(fs_info,
7292 devid, dev_uuid, true);
7293 return -ENOENT;
7294 }
7295 btrfs_report_missing_device(fs_info, devid,
7296 dev_uuid, false);
7297 }
7298
7299 if (!device->bdev &&
7300 !test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
7301 /*
7302 * this happens when a device that was properly setup
7303 * in the device info lists suddenly goes bad.
7304 * device->bdev is NULL, and so we have to set
7305 * device->missing to one here
7306 */
7307 device->fs_devices->missing_devices++;
7308 set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
7309 }
7310
7311 /* Move the device to its own fs_devices */
7312 if (device->fs_devices != fs_devices) {
7313 ASSERT(test_bit(BTRFS_DEV_STATE_MISSING,
7314 &device->dev_state));
7315
7316 list_move(&device->dev_list, &fs_devices->devices);
7317 device->fs_devices->num_devices--;
7318 fs_devices->num_devices++;
7319
7320 device->fs_devices->missing_devices--;
7321 fs_devices->missing_devices++;
7322
7323 device->fs_devices = fs_devices;
7324 }
7325 }
7326
7327 if (device->fs_devices != fs_info->fs_devices) {
7328 BUG_ON(test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state));
7329 if (device->generation !=
7330 btrfs_device_generation(leaf, dev_item))
7331 return -EINVAL;
7332 }
7333
7334 fill_device_from_item(leaf, dev_item, device);
7335 if (device->bdev) {
7336 u64 max_total_bytes = bdev_nr_bytes(device->bdev);
7337
7338 if (device->total_bytes > max_total_bytes) {
7339 btrfs_err(fs_info,
7340 "device total_bytes should be at most %llu but found %llu",
7341 max_total_bytes, device->total_bytes);
7342 return -EINVAL;
7343 }
7344 }
7345 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
7346 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
7347 !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
7348 device->fs_devices->total_rw_bytes += device->total_bytes;
7349 atomic64_add(device->total_bytes - device->bytes_used,
7350 &fs_info->free_chunk_space);
7351 }
7352 ret = 0;
7353 return ret;
7354 }
7355
btrfs_read_sys_array(struct btrfs_fs_info * fs_info)7356 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info)
7357 {
7358 struct btrfs_super_block *super_copy = fs_info->super_copy;
7359 struct extent_buffer *sb;
7360 u8 *array_ptr;
7361 unsigned long sb_array_offset;
7362 int ret = 0;
7363 u32 array_size;
7364 u32 cur_offset;
7365 struct btrfs_key key;
7366
7367 ASSERT(BTRFS_SUPER_INFO_SIZE <= fs_info->nodesize);
7368
7369 /*
7370 * We allocated a dummy extent, just to use extent buffer accessors.
7371 * There will be unused space after BTRFS_SUPER_INFO_SIZE, but
7372 * that's fine, we will not go beyond system chunk array anyway.
7373 */
7374 sb = alloc_dummy_extent_buffer(fs_info, BTRFS_SUPER_INFO_OFFSET);
7375 if (!sb)
7376 return -ENOMEM;
7377 set_extent_buffer_uptodate(sb);
7378
7379 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
7380 array_size = btrfs_super_sys_array_size(super_copy);
7381
7382 array_ptr = super_copy->sys_chunk_array;
7383 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
7384 cur_offset = 0;
7385
7386 while (cur_offset < array_size) {
7387 struct btrfs_chunk *chunk;
7388 struct btrfs_disk_key *disk_key = (struct btrfs_disk_key *)array_ptr;
7389 u32 len = sizeof(*disk_key);
7390
7391 /*
7392 * The sys_chunk_array has been already verified at super block
7393 * read time. Only do ASSERT()s for basic checks.
7394 */
7395 ASSERT(cur_offset + len <= array_size);
7396
7397 btrfs_disk_key_to_cpu(&key, disk_key);
7398
7399 array_ptr += len;
7400 sb_array_offset += len;
7401 cur_offset += len;
7402
7403 ASSERT(key.type == BTRFS_CHUNK_ITEM_KEY);
7404
7405 chunk = (struct btrfs_chunk *)sb_array_offset;
7406 ASSERT(btrfs_chunk_type(sb, chunk) & BTRFS_BLOCK_GROUP_SYSTEM);
7407
7408 len = btrfs_chunk_item_size(btrfs_chunk_num_stripes(sb, chunk));
7409
7410 ASSERT(cur_offset + len <= array_size);
7411
7412 ret = read_one_chunk(&key, sb, chunk);
7413 if (ret)
7414 break;
7415
7416 array_ptr += len;
7417 sb_array_offset += len;
7418 cur_offset += len;
7419 }
7420 clear_extent_buffer_uptodate(sb);
7421 free_extent_buffer_stale(sb);
7422 return ret;
7423 }
7424
7425 /*
7426 * Check if all chunks in the fs are OK for read-write degraded mount
7427 *
7428 * If the @failing_dev is specified, it's accounted as missing.
7429 *
7430 * Return true if all chunks meet the minimal RW mount requirements.
7431 * Return false if any chunk doesn't meet the minimal RW mount requirements.
7432 */
btrfs_check_rw_degradable(struct btrfs_fs_info * fs_info,struct btrfs_device * failing_dev)7433 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
7434 struct btrfs_device *failing_dev)
7435 {
7436 struct btrfs_chunk_map *map;
7437 u64 next_start;
7438 bool ret = true;
7439
7440 map = btrfs_find_chunk_map(fs_info, 0, U64_MAX);
7441 /* No chunk at all? Return false anyway */
7442 if (!map) {
7443 ret = false;
7444 goto out;
7445 }
7446 while (map) {
7447 int missing = 0;
7448 int max_tolerated;
7449 int i;
7450
7451 max_tolerated =
7452 btrfs_get_num_tolerated_disk_barrier_failures(
7453 map->type);
7454 for (i = 0; i < map->num_stripes; i++) {
7455 struct btrfs_device *dev = map->stripes[i].dev;
7456
7457 if (!dev || !dev->bdev ||
7458 test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) ||
7459 dev->last_flush_error)
7460 missing++;
7461 else if (failing_dev && failing_dev == dev)
7462 missing++;
7463 }
7464 if (missing > max_tolerated) {
7465 if (!failing_dev)
7466 btrfs_warn(fs_info,
7467 "chunk %llu missing %d devices, max tolerance is %d for writable mount",
7468 map->start, missing, max_tolerated);
7469 btrfs_free_chunk_map(map);
7470 ret = false;
7471 goto out;
7472 }
7473 next_start = map->start + map->chunk_len;
7474 btrfs_free_chunk_map(map);
7475
7476 map = btrfs_find_chunk_map(fs_info, next_start, U64_MAX - next_start);
7477 }
7478 out:
7479 return ret;
7480 }
7481
readahead_tree_node_children(struct extent_buffer * node)7482 static void readahead_tree_node_children(struct extent_buffer *node)
7483 {
7484 int i;
7485 const int nr_items = btrfs_header_nritems(node);
7486
7487 for (i = 0; i < nr_items; i++)
7488 btrfs_readahead_node_child(node, i);
7489 }
7490
btrfs_read_chunk_tree(struct btrfs_fs_info * fs_info)7491 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info)
7492 {
7493 struct btrfs_root *root = fs_info->chunk_root;
7494 struct btrfs_path *path;
7495 struct extent_buffer *leaf;
7496 struct btrfs_key key;
7497 struct btrfs_key found_key;
7498 int ret;
7499 int slot;
7500 int iter_ret = 0;
7501 u64 total_dev = 0;
7502 u64 last_ra_node = 0;
7503
7504 path = btrfs_alloc_path();
7505 if (!path)
7506 return -ENOMEM;
7507
7508 /*
7509 * uuid_mutex is needed only if we are mounting a sprout FS
7510 * otherwise we don't need it.
7511 */
7512 mutex_lock(&uuid_mutex);
7513
7514 /*
7515 * It is possible for mount and umount to race in such a way that
7516 * we execute this code path, but open_fs_devices failed to clear
7517 * total_rw_bytes. We certainly want it cleared before reading the
7518 * device items, so clear it here.
7519 */
7520 fs_info->fs_devices->total_rw_bytes = 0;
7521
7522 /*
7523 * Lockdep complains about possible circular locking dependency between
7524 * a disk's open_mutex (struct gendisk.open_mutex), the rw semaphores
7525 * used for freeze procection of a fs (struct super_block.s_writers),
7526 * which we take when starting a transaction, and extent buffers of the
7527 * chunk tree if we call read_one_dev() while holding a lock on an
7528 * extent buffer of the chunk tree. Since we are mounting the filesystem
7529 * and at this point there can't be any concurrent task modifying the
7530 * chunk tree, to keep it simple, just skip locking on the chunk tree.
7531 */
7532 ASSERT(!test_bit(BTRFS_FS_OPEN, &fs_info->flags));
7533 path->skip_locking = 1;
7534
7535 /*
7536 * Read all device items, and then all the chunk items. All
7537 * device items are found before any chunk item (their object id
7538 * is smaller than the lowest possible object id for a chunk
7539 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
7540 */
7541 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
7542 key.offset = 0;
7543 key.type = 0;
7544 btrfs_for_each_slot(root, &key, &found_key, path, iter_ret) {
7545 struct extent_buffer *node = path->nodes[1];
7546
7547 leaf = path->nodes[0];
7548 slot = path->slots[0];
7549
7550 if (node) {
7551 if (last_ra_node != node->start) {
7552 readahead_tree_node_children(node);
7553 last_ra_node = node->start;
7554 }
7555 }
7556 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
7557 struct btrfs_dev_item *dev_item;
7558 dev_item = btrfs_item_ptr(leaf, slot,
7559 struct btrfs_dev_item);
7560 ret = read_one_dev(leaf, dev_item);
7561 if (ret)
7562 goto error;
7563 total_dev++;
7564 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
7565 struct btrfs_chunk *chunk;
7566
7567 /*
7568 * We are only called at mount time, so no need to take
7569 * fs_info->chunk_mutex. Plus, to avoid lockdep warnings,
7570 * we always lock first fs_info->chunk_mutex before
7571 * acquiring any locks on the chunk tree. This is a
7572 * requirement for chunk allocation, see the comment on
7573 * top of btrfs_chunk_alloc() for details.
7574 */
7575 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
7576 ret = read_one_chunk(&found_key, leaf, chunk);
7577 if (ret)
7578 goto error;
7579 }
7580 }
7581 /* Catch error found during iteration */
7582 if (iter_ret < 0) {
7583 ret = iter_ret;
7584 goto error;
7585 }
7586
7587 /*
7588 * After loading chunk tree, we've got all device information,
7589 * do another round of validation checks.
7590 */
7591 if (total_dev != fs_info->fs_devices->total_devices) {
7592 btrfs_warn(fs_info,
7593 "super block num_devices %llu mismatch with DEV_ITEM count %llu, will be repaired on next transaction commit",
7594 btrfs_super_num_devices(fs_info->super_copy),
7595 total_dev);
7596 fs_info->fs_devices->total_devices = total_dev;
7597 btrfs_set_super_num_devices(fs_info->super_copy, total_dev);
7598 }
7599 if (btrfs_super_total_bytes(fs_info->super_copy) <
7600 fs_info->fs_devices->total_rw_bytes) {
7601 btrfs_err(fs_info,
7602 "super_total_bytes %llu mismatch with fs_devices total_rw_bytes %llu",
7603 btrfs_super_total_bytes(fs_info->super_copy),
7604 fs_info->fs_devices->total_rw_bytes);
7605 ret = -EINVAL;
7606 goto error;
7607 }
7608 ret = 0;
7609 error:
7610 mutex_unlock(&uuid_mutex);
7611
7612 btrfs_free_path(path);
7613 return ret;
7614 }
7615
btrfs_init_devices_late(struct btrfs_fs_info * fs_info)7616 int btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
7617 {
7618 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
7619 struct btrfs_device *device;
7620 int ret = 0;
7621
7622 mutex_lock(&fs_devices->device_list_mutex);
7623 list_for_each_entry(device, &fs_devices->devices, dev_list)
7624 device->fs_info = fs_info;
7625
7626 list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
7627 list_for_each_entry(device, &seed_devs->devices, dev_list) {
7628 device->fs_info = fs_info;
7629 ret = btrfs_get_dev_zone_info(device, false);
7630 if (ret)
7631 break;
7632 }
7633
7634 seed_devs->fs_info = fs_info;
7635 }
7636 mutex_unlock(&fs_devices->device_list_mutex);
7637
7638 return ret;
7639 }
7640
btrfs_dev_stats_value(const struct extent_buffer * eb,const struct btrfs_dev_stats_item * ptr,int index)7641 static u64 btrfs_dev_stats_value(const struct extent_buffer *eb,
7642 const struct btrfs_dev_stats_item *ptr,
7643 int index)
7644 {
7645 u64 val;
7646
7647 read_extent_buffer(eb, &val,
7648 offsetof(struct btrfs_dev_stats_item, values) +
7649 ((unsigned long)ptr) + (index * sizeof(u64)),
7650 sizeof(val));
7651 return val;
7652 }
7653
btrfs_set_dev_stats_value(struct extent_buffer * eb,struct btrfs_dev_stats_item * ptr,int index,u64 val)7654 static void btrfs_set_dev_stats_value(struct extent_buffer *eb,
7655 struct btrfs_dev_stats_item *ptr,
7656 int index, u64 val)
7657 {
7658 write_extent_buffer(eb, &val,
7659 offsetof(struct btrfs_dev_stats_item, values) +
7660 ((unsigned long)ptr) + (index * sizeof(u64)),
7661 sizeof(val));
7662 }
7663
btrfs_device_init_dev_stats(struct btrfs_device * device,struct btrfs_path * path)7664 static int btrfs_device_init_dev_stats(struct btrfs_device *device,
7665 struct btrfs_path *path)
7666 {
7667 struct btrfs_dev_stats_item *ptr;
7668 struct extent_buffer *eb;
7669 struct btrfs_key key;
7670 int item_size;
7671 int i, ret, slot;
7672
7673 if (!device->fs_info->dev_root)
7674 return 0;
7675
7676 key.objectid = BTRFS_DEV_STATS_OBJECTID;
7677 key.type = BTRFS_PERSISTENT_ITEM_KEY;
7678 key.offset = device->devid;
7679 ret = btrfs_search_slot(NULL, device->fs_info->dev_root, &key, path, 0, 0);
7680 if (ret) {
7681 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7682 btrfs_dev_stat_set(device, i, 0);
7683 device->dev_stats_valid = 1;
7684 btrfs_release_path(path);
7685 return ret < 0 ? ret : 0;
7686 }
7687 slot = path->slots[0];
7688 eb = path->nodes[0];
7689 item_size = btrfs_item_size(eb, slot);
7690
7691 ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_stats_item);
7692
7693 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
7694 if (item_size >= (1 + i) * sizeof(__le64))
7695 btrfs_dev_stat_set(device, i,
7696 btrfs_dev_stats_value(eb, ptr, i));
7697 else
7698 btrfs_dev_stat_set(device, i, 0);
7699 }
7700
7701 device->dev_stats_valid = 1;
7702 btrfs_dev_stat_print_on_load(device);
7703 btrfs_release_path(path);
7704
7705 return 0;
7706 }
7707
btrfs_init_dev_stats(struct btrfs_fs_info * fs_info)7708 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
7709 {
7710 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
7711 struct btrfs_device *device;
7712 struct btrfs_path *path = NULL;
7713 int ret = 0;
7714
7715 path = btrfs_alloc_path();
7716 if (!path)
7717 return -ENOMEM;
7718
7719 mutex_lock(&fs_devices->device_list_mutex);
7720 list_for_each_entry(device, &fs_devices->devices, dev_list) {
7721 ret = btrfs_device_init_dev_stats(device, path);
7722 if (ret)
7723 goto out;
7724 }
7725 list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
7726 list_for_each_entry(device, &seed_devs->devices, dev_list) {
7727 ret = btrfs_device_init_dev_stats(device, path);
7728 if (ret)
7729 goto out;
7730 }
7731 }
7732 out:
7733 mutex_unlock(&fs_devices->device_list_mutex);
7734
7735 btrfs_free_path(path);
7736 return ret;
7737 }
7738
update_dev_stat_item(struct btrfs_trans_handle * trans,struct btrfs_device * device)7739 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
7740 struct btrfs_device *device)
7741 {
7742 struct btrfs_fs_info *fs_info = trans->fs_info;
7743 struct btrfs_root *dev_root = fs_info->dev_root;
7744 struct btrfs_path *path;
7745 struct btrfs_key key;
7746 struct extent_buffer *eb;
7747 struct btrfs_dev_stats_item *ptr;
7748 int ret;
7749 int i;
7750
7751 key.objectid = BTRFS_DEV_STATS_OBJECTID;
7752 key.type = BTRFS_PERSISTENT_ITEM_KEY;
7753 key.offset = device->devid;
7754
7755 path = btrfs_alloc_path();
7756 if (!path)
7757 return -ENOMEM;
7758 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
7759 if (ret < 0) {
7760 btrfs_warn_in_rcu(fs_info,
7761 "error %d while searching for dev_stats item for device %s",
7762 ret, btrfs_dev_name(device));
7763 goto out;
7764 }
7765
7766 if (ret == 0 &&
7767 btrfs_item_size(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
7768 /* need to delete old one and insert a new one */
7769 ret = btrfs_del_item(trans, dev_root, path);
7770 if (ret != 0) {
7771 btrfs_warn_in_rcu(fs_info,
7772 "delete too small dev_stats item for device %s failed %d",
7773 btrfs_dev_name(device), ret);
7774 goto out;
7775 }
7776 ret = 1;
7777 }
7778
7779 if (ret == 1) {
7780 /* need to insert a new item */
7781 btrfs_release_path(path);
7782 ret = btrfs_insert_empty_item(trans, dev_root, path,
7783 &key, sizeof(*ptr));
7784 if (ret < 0) {
7785 btrfs_warn_in_rcu(fs_info,
7786 "insert dev_stats item for device %s failed %d",
7787 btrfs_dev_name(device), ret);
7788 goto out;
7789 }
7790 }
7791
7792 eb = path->nodes[0];
7793 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
7794 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7795 btrfs_set_dev_stats_value(eb, ptr, i,
7796 btrfs_dev_stat_read(device, i));
7797 out:
7798 btrfs_free_path(path);
7799 return ret;
7800 }
7801
7802 /*
7803 * called from commit_transaction. Writes all changed device stats to disk.
7804 */
btrfs_run_dev_stats(struct btrfs_trans_handle * trans)7805 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans)
7806 {
7807 struct btrfs_fs_info *fs_info = trans->fs_info;
7808 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7809 struct btrfs_device *device;
7810 int stats_cnt;
7811 int ret = 0;
7812
7813 mutex_lock(&fs_devices->device_list_mutex);
7814 list_for_each_entry(device, &fs_devices->devices, dev_list) {
7815 stats_cnt = atomic_read(&device->dev_stats_ccnt);
7816 if (!device->dev_stats_valid || stats_cnt == 0)
7817 continue;
7818
7819
7820 /*
7821 * There is a LOAD-LOAD control dependency between the value of
7822 * dev_stats_ccnt and updating the on-disk values which requires
7823 * reading the in-memory counters. Such control dependencies
7824 * require explicit read memory barriers.
7825 *
7826 * This memory barriers pairs with smp_mb__before_atomic in
7827 * btrfs_dev_stat_inc/btrfs_dev_stat_set and with the full
7828 * barrier implied by atomic_xchg in
7829 * btrfs_dev_stats_read_and_reset
7830 */
7831 smp_rmb();
7832
7833 ret = update_dev_stat_item(trans, device);
7834 if (!ret)
7835 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
7836 }
7837 mutex_unlock(&fs_devices->device_list_mutex);
7838
7839 return ret;
7840 }
7841
btrfs_dev_stat_inc_and_print(struct btrfs_device * dev,int index)7842 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
7843 {
7844 btrfs_dev_stat_inc(dev, index);
7845
7846 if (!dev->dev_stats_valid)
7847 return;
7848 btrfs_err_rl_in_rcu(dev->fs_info,
7849 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
7850 btrfs_dev_name(dev),
7851 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
7852 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
7853 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
7854 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
7855 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
7856 }
7857
btrfs_dev_stat_print_on_load(struct btrfs_device * dev)7858 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
7859 {
7860 int i;
7861
7862 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7863 if (btrfs_dev_stat_read(dev, i) != 0)
7864 break;
7865 if (i == BTRFS_DEV_STAT_VALUES_MAX)
7866 return; /* all values == 0, suppress message */
7867
7868 btrfs_info_in_rcu(dev->fs_info,
7869 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
7870 btrfs_dev_name(dev),
7871 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
7872 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
7873 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
7874 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
7875 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
7876 }
7877
btrfs_get_dev_stats(struct btrfs_fs_info * fs_info,struct btrfs_ioctl_get_dev_stats * stats)7878 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
7879 struct btrfs_ioctl_get_dev_stats *stats)
7880 {
7881 BTRFS_DEV_LOOKUP_ARGS(args);
7882 struct btrfs_device *dev;
7883 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7884 int i;
7885
7886 mutex_lock(&fs_devices->device_list_mutex);
7887 args.devid = stats->devid;
7888 dev = btrfs_find_device(fs_info->fs_devices, &args);
7889 mutex_unlock(&fs_devices->device_list_mutex);
7890
7891 if (!dev) {
7892 btrfs_warn(fs_info, "get dev_stats failed, device not found");
7893 return -ENODEV;
7894 } else if (!dev->dev_stats_valid) {
7895 btrfs_warn(fs_info, "get dev_stats failed, not yet valid");
7896 return -ENODEV;
7897 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
7898 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
7899 if (stats->nr_items > i)
7900 stats->values[i] =
7901 btrfs_dev_stat_read_and_reset(dev, i);
7902 else
7903 btrfs_dev_stat_set(dev, i, 0);
7904 }
7905 btrfs_info(fs_info, "device stats zeroed by %s (%d)",
7906 current->comm, task_pid_nr(current));
7907 } else {
7908 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7909 if (stats->nr_items > i)
7910 stats->values[i] = btrfs_dev_stat_read(dev, i);
7911 }
7912 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
7913 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
7914 return 0;
7915 }
7916
7917 /*
7918 * Update the size and bytes used for each device where it changed. This is
7919 * delayed since we would otherwise get errors while writing out the
7920 * superblocks.
7921 *
7922 * Must be invoked during transaction commit.
7923 */
btrfs_commit_device_sizes(struct btrfs_transaction * trans)7924 void btrfs_commit_device_sizes(struct btrfs_transaction *trans)
7925 {
7926 struct btrfs_device *curr, *next;
7927
7928 ASSERT(trans->state == TRANS_STATE_COMMIT_DOING);
7929
7930 if (list_empty(&trans->dev_update_list))
7931 return;
7932
7933 /*
7934 * We don't need the device_list_mutex here. This list is owned by the
7935 * transaction and the transaction must complete before the device is
7936 * released.
7937 */
7938 mutex_lock(&trans->fs_info->chunk_mutex);
7939 list_for_each_entry_safe(curr, next, &trans->dev_update_list,
7940 post_commit_list) {
7941 list_del_init(&curr->post_commit_list);
7942 curr->commit_total_bytes = curr->disk_total_bytes;
7943 curr->commit_bytes_used = curr->bytes_used;
7944 }
7945 mutex_unlock(&trans->fs_info->chunk_mutex);
7946 }
7947
7948 /*
7949 * Multiplicity factor for simple profiles: DUP, RAID1-like and RAID10.
7950 */
btrfs_bg_type_to_factor(u64 flags)7951 int btrfs_bg_type_to_factor(u64 flags)
7952 {
7953 const int index = btrfs_bg_flags_to_raid_index(flags);
7954
7955 return btrfs_raid_array[index].ncopies;
7956 }
7957
7958
7959
verify_one_dev_extent(struct btrfs_fs_info * fs_info,u64 chunk_offset,u64 devid,u64 physical_offset,u64 physical_len)7960 static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
7961 u64 chunk_offset, u64 devid,
7962 u64 physical_offset, u64 physical_len)
7963 {
7964 struct btrfs_dev_lookup_args args = { .devid = devid };
7965 struct btrfs_chunk_map *map;
7966 struct btrfs_device *dev;
7967 u64 stripe_len;
7968 bool found = false;
7969 int ret = 0;
7970 int i;
7971
7972 map = btrfs_find_chunk_map(fs_info, chunk_offset, 1);
7973 if (!map) {
7974 btrfs_err(fs_info,
7975 "dev extent physical offset %llu on devid %llu doesn't have corresponding chunk",
7976 physical_offset, devid);
7977 ret = -EUCLEAN;
7978 goto out;
7979 }
7980
7981 stripe_len = btrfs_calc_stripe_length(map);
7982 if (physical_len != stripe_len) {
7983 btrfs_err(fs_info,
7984 "dev extent physical offset %llu on devid %llu length doesn't match chunk %llu, have %llu expect %llu",
7985 physical_offset, devid, map->start, physical_len,
7986 stripe_len);
7987 ret = -EUCLEAN;
7988 goto out;
7989 }
7990
7991 /*
7992 * Very old mkfs.btrfs (before v4.1) will not respect the reserved
7993 * space. Although kernel can handle it without problem, better to warn
7994 * the users.
7995 */
7996 if (physical_offset < BTRFS_DEVICE_RANGE_RESERVED)
7997 btrfs_warn(fs_info,
7998 "devid %llu physical %llu len %llu inside the reserved space",
7999 devid, physical_offset, physical_len);
8000
8001 for (i = 0; i < map->num_stripes; i++) {
8002 if (map->stripes[i].dev->devid == devid &&
8003 map->stripes[i].physical == physical_offset) {
8004 found = true;
8005 if (map->verified_stripes >= map->num_stripes) {
8006 btrfs_err(fs_info,
8007 "too many dev extents for chunk %llu found",
8008 map->start);
8009 ret = -EUCLEAN;
8010 goto out;
8011 }
8012 map->verified_stripes++;
8013 break;
8014 }
8015 }
8016 if (!found) {
8017 btrfs_err(fs_info,
8018 "dev extent physical offset %llu devid %llu has no corresponding chunk",
8019 physical_offset, devid);
8020 ret = -EUCLEAN;
8021 }
8022
8023 /* Make sure no dev extent is beyond device boundary */
8024 dev = btrfs_find_device(fs_info->fs_devices, &args);
8025 if (!dev) {
8026 btrfs_err(fs_info, "failed to find devid %llu", devid);
8027 ret = -EUCLEAN;
8028 goto out;
8029 }
8030
8031 if (physical_offset + physical_len > dev->disk_total_bytes) {
8032 btrfs_err(fs_info,
8033 "dev extent devid %llu physical offset %llu len %llu is beyond device boundary %llu",
8034 devid, physical_offset, physical_len,
8035 dev->disk_total_bytes);
8036 ret = -EUCLEAN;
8037 goto out;
8038 }
8039
8040 if (dev->zone_info) {
8041 u64 zone_size = dev->zone_info->zone_size;
8042
8043 if (!IS_ALIGNED(physical_offset, zone_size) ||
8044 !IS_ALIGNED(physical_len, zone_size)) {
8045 btrfs_err(fs_info,
8046 "zoned: dev extent devid %llu physical offset %llu len %llu is not aligned to device zone",
8047 devid, physical_offset, physical_len);
8048 ret = -EUCLEAN;
8049 goto out;
8050 }
8051 }
8052
8053 out:
8054 btrfs_free_chunk_map(map);
8055 return ret;
8056 }
8057
verify_chunk_dev_extent_mapping(struct btrfs_fs_info * fs_info)8058 static int verify_chunk_dev_extent_mapping(struct btrfs_fs_info *fs_info)
8059 {
8060 struct rb_node *node;
8061 int ret = 0;
8062
8063 read_lock(&fs_info->mapping_tree_lock);
8064 for (node = rb_first_cached(&fs_info->mapping_tree); node; node = rb_next(node)) {
8065 struct btrfs_chunk_map *map;
8066
8067 map = rb_entry(node, struct btrfs_chunk_map, rb_node);
8068 if (map->num_stripes != map->verified_stripes) {
8069 btrfs_err(fs_info,
8070 "chunk %llu has missing dev extent, have %d expect %d",
8071 map->start, map->verified_stripes, map->num_stripes);
8072 ret = -EUCLEAN;
8073 goto out;
8074 }
8075 }
8076 out:
8077 read_unlock(&fs_info->mapping_tree_lock);
8078 return ret;
8079 }
8080
8081 /*
8082 * Ensure that all dev extents are mapped to correct chunk, otherwise
8083 * later chunk allocation/free would cause unexpected behavior.
8084 *
8085 * NOTE: This will iterate through the whole device tree, which should be of
8086 * the same size level as the chunk tree. This slightly increases mount time.
8087 */
btrfs_verify_dev_extents(struct btrfs_fs_info * fs_info)8088 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info)
8089 {
8090 struct btrfs_path *path;
8091 struct btrfs_root *root = fs_info->dev_root;
8092 struct btrfs_key key;
8093 u64 prev_devid = 0;
8094 u64 prev_dev_ext_end = 0;
8095 int ret = 0;
8096
8097 /*
8098 * We don't have a dev_root because we mounted with ignorebadroots and
8099 * failed to load the root, so we want to skip the verification in this
8100 * case for sure.
8101 *
8102 * However if the dev root is fine, but the tree itself is corrupted
8103 * we'd still fail to mount. This verification is only to make sure
8104 * writes can happen safely, so instead just bypass this check
8105 * completely in the case of IGNOREBADROOTS.
8106 */
8107 if (btrfs_test_opt(fs_info, IGNOREBADROOTS))
8108 return 0;
8109
8110 key.objectid = 1;
8111 key.type = BTRFS_DEV_EXTENT_KEY;
8112 key.offset = 0;
8113
8114 path = btrfs_alloc_path();
8115 if (!path)
8116 return -ENOMEM;
8117
8118 path->reada = READA_FORWARD;
8119 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
8120 if (ret < 0)
8121 goto out;
8122
8123 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
8124 ret = btrfs_next_leaf(root, path);
8125 if (ret < 0)
8126 goto out;
8127 /* No dev extents at all? Not good */
8128 if (ret > 0) {
8129 ret = -EUCLEAN;
8130 goto out;
8131 }
8132 }
8133 while (1) {
8134 struct extent_buffer *leaf = path->nodes[0];
8135 struct btrfs_dev_extent *dext;
8136 int slot = path->slots[0];
8137 u64 chunk_offset;
8138 u64 physical_offset;
8139 u64 physical_len;
8140 u64 devid;
8141
8142 btrfs_item_key_to_cpu(leaf, &key, slot);
8143 if (key.type != BTRFS_DEV_EXTENT_KEY)
8144 break;
8145 devid = key.objectid;
8146 physical_offset = key.offset;
8147
8148 dext = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent);
8149 chunk_offset = btrfs_dev_extent_chunk_offset(leaf, dext);
8150 physical_len = btrfs_dev_extent_length(leaf, dext);
8151
8152 /* Check if this dev extent overlaps with the previous one */
8153 if (devid == prev_devid && physical_offset < prev_dev_ext_end) {
8154 btrfs_err(fs_info,
8155 "dev extent devid %llu physical offset %llu overlap with previous dev extent end %llu",
8156 devid, physical_offset, prev_dev_ext_end);
8157 ret = -EUCLEAN;
8158 goto out;
8159 }
8160
8161 ret = verify_one_dev_extent(fs_info, chunk_offset, devid,
8162 physical_offset, physical_len);
8163 if (ret < 0)
8164 goto out;
8165 prev_devid = devid;
8166 prev_dev_ext_end = physical_offset + physical_len;
8167
8168 ret = btrfs_next_item(root, path);
8169 if (ret < 0)
8170 goto out;
8171 if (ret > 0) {
8172 ret = 0;
8173 break;
8174 }
8175 }
8176
8177 /* Ensure all chunks have corresponding dev extents */
8178 ret = verify_chunk_dev_extent_mapping(fs_info);
8179 out:
8180 btrfs_free_path(path);
8181 return ret;
8182 }
8183
8184 /*
8185 * Check whether the given block group or device is pinned by any inode being
8186 * used as a swapfile.
8187 */
btrfs_pinned_by_swapfile(struct btrfs_fs_info * fs_info,void * ptr)8188 bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr)
8189 {
8190 struct btrfs_swapfile_pin *sp;
8191 struct rb_node *node;
8192
8193 spin_lock(&fs_info->swapfile_pins_lock);
8194 node = fs_info->swapfile_pins.rb_node;
8195 while (node) {
8196 sp = rb_entry(node, struct btrfs_swapfile_pin, node);
8197 if (ptr < sp->ptr)
8198 node = node->rb_left;
8199 else if (ptr > sp->ptr)
8200 node = node->rb_right;
8201 else
8202 break;
8203 }
8204 spin_unlock(&fs_info->swapfile_pins_lock);
8205 return node != NULL;
8206 }
8207
relocating_repair_kthread(void * data)8208 static int relocating_repair_kthread(void *data)
8209 {
8210 struct btrfs_block_group *cache = data;
8211 struct btrfs_fs_info *fs_info = cache->fs_info;
8212 u64 target;
8213 int ret = 0;
8214
8215 target = cache->start;
8216 btrfs_put_block_group(cache);
8217
8218 sb_start_write(fs_info->sb);
8219 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
8220 btrfs_info(fs_info,
8221 "zoned: skip relocating block group %llu to repair: EBUSY",
8222 target);
8223 sb_end_write(fs_info->sb);
8224 return -EBUSY;
8225 }
8226
8227 mutex_lock(&fs_info->reclaim_bgs_lock);
8228
8229 /* Ensure block group still exists */
8230 cache = btrfs_lookup_block_group(fs_info, target);
8231 if (!cache)
8232 goto out;
8233
8234 if (!test_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags))
8235 goto out;
8236
8237 ret = btrfs_may_alloc_data_chunk(fs_info, target);
8238 if (ret < 0)
8239 goto out;
8240
8241 btrfs_info(fs_info,
8242 "zoned: relocating block group %llu to repair IO failure",
8243 target);
8244 ret = btrfs_relocate_chunk(fs_info, target);
8245
8246 out:
8247 if (cache)
8248 btrfs_put_block_group(cache);
8249 mutex_unlock(&fs_info->reclaim_bgs_lock);
8250 btrfs_exclop_finish(fs_info);
8251 sb_end_write(fs_info->sb);
8252
8253 return ret;
8254 }
8255
btrfs_repair_one_zone(struct btrfs_fs_info * fs_info,u64 logical)8256 bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical)
8257 {
8258 struct btrfs_block_group *cache;
8259
8260 if (!btrfs_is_zoned(fs_info))
8261 return false;
8262
8263 /* Do not attempt to repair in degraded state */
8264 if (btrfs_test_opt(fs_info, DEGRADED))
8265 return true;
8266
8267 cache = btrfs_lookup_block_group(fs_info, logical);
8268 if (!cache)
8269 return true;
8270
8271 if (test_and_set_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags)) {
8272 btrfs_put_block_group(cache);
8273 return true;
8274 }
8275
8276 kthread_run(relocating_repair_kthread, cache,
8277 "btrfs-relocating-repair");
8278
8279 return true;
8280 }
8281
map_raid56_repair_block(struct btrfs_io_context * bioc,struct btrfs_io_stripe * smap,u64 logical)8282 static void map_raid56_repair_block(struct btrfs_io_context *bioc,
8283 struct btrfs_io_stripe *smap,
8284 u64 logical)
8285 {
8286 int data_stripes = nr_bioc_data_stripes(bioc);
8287 int i;
8288
8289 for (i = 0; i < data_stripes; i++) {
8290 u64 stripe_start = bioc->full_stripe_logical +
8291 btrfs_stripe_nr_to_offset(i);
8292
8293 if (logical >= stripe_start &&
8294 logical < stripe_start + BTRFS_STRIPE_LEN)
8295 break;
8296 }
8297 ASSERT(i < data_stripes);
8298 smap->dev = bioc->stripes[i].dev;
8299 smap->physical = bioc->stripes[i].physical +
8300 ((logical - bioc->full_stripe_logical) &
8301 BTRFS_STRIPE_LEN_MASK);
8302 }
8303
8304 /*
8305 * Map a repair write into a single device.
8306 *
8307 * A repair write is triggered by read time repair or scrub, which would only
8308 * update the contents of a single device.
8309 * Not update any other mirrors nor go through RMW path.
8310 *
8311 * Callers should ensure:
8312 *
8313 * - Call btrfs_bio_counter_inc_blocked() first
8314 * - The range does not cross stripe boundary
8315 * - Has a valid @mirror_num passed in.
8316 */
btrfs_map_repair_block(struct btrfs_fs_info * fs_info,struct btrfs_io_stripe * smap,u64 logical,u32 length,int mirror_num)8317 int btrfs_map_repair_block(struct btrfs_fs_info *fs_info,
8318 struct btrfs_io_stripe *smap, u64 logical,
8319 u32 length, int mirror_num)
8320 {
8321 struct btrfs_io_context *bioc = NULL;
8322 u64 map_length = length;
8323 int mirror_ret = mirror_num;
8324 int ret;
8325
8326 ASSERT(mirror_num > 0);
8327
8328 ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical, &map_length,
8329 &bioc, smap, &mirror_ret);
8330 if (ret < 0)
8331 return ret;
8332
8333 /* The map range should not cross stripe boundary. */
8334 ASSERT(map_length >= length);
8335
8336 /* Already mapped to single stripe. */
8337 if (!bioc)
8338 goto out;
8339
8340 /* Map the RAID56 multi-stripe writes to a single one. */
8341 if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
8342 map_raid56_repair_block(bioc, smap, logical);
8343 goto out;
8344 }
8345
8346 ASSERT(mirror_num <= bioc->num_stripes);
8347 smap->dev = bioc->stripes[mirror_num - 1].dev;
8348 smap->physical = bioc->stripes[mirror_num - 1].physical;
8349 out:
8350 btrfs_put_bioc(bioc);
8351 ASSERT(smap->dev);
8352 return 0;
8353 }
8354