xref: /linux/fs/bcachefs/bcachefs_ioctl.h (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _BCACHEFS_IOCTL_H
3 #define _BCACHEFS_IOCTL_H
4 
5 #include <linux/uuid.h>
6 #include <asm/ioctl.h>
7 #include "bcachefs_format.h"
8 
9 /*
10  * Flags common to multiple ioctls:
11  */
12 #define BCH_FORCE_IF_DATA_LOST		(1 << 0)
13 #define BCH_FORCE_IF_METADATA_LOST	(1 << 1)
14 #define BCH_FORCE_IF_DATA_DEGRADED	(1 << 2)
15 #define BCH_FORCE_IF_METADATA_DEGRADED	(1 << 3)
16 
17 #define BCH_FORCE_IF_LOST			\
18 	(BCH_FORCE_IF_DATA_LOST|		\
19 	 BCH_FORCE_IF_METADATA_LOST)
20 #define BCH_FORCE_IF_DEGRADED			\
21 	(BCH_FORCE_IF_DATA_DEGRADED|		\
22 	 BCH_FORCE_IF_METADATA_DEGRADED)
23 
24 /*
25  * If cleared, ioctl that refer to a device pass it as a pointer to a pathname
26  * (e.g. /dev/sda1); if set, the dev field is the device's index within the
27  * filesystem:
28  */
29 #define BCH_BY_INDEX			(1 << 4)
30 
31 /*
32  * For BCH_IOCTL_READ_SUPER: get superblock of a specific device, not filesystem
33  * wide superblock:
34  */
35 #define BCH_READ_DEV			(1 << 5)
36 
37 /* global control dev: */
38 
39 /* These are currently broken, and probably unnecessary: */
40 #if 0
41 #define BCH_IOCTL_ASSEMBLE	_IOW(0xbc, 1, struct bch_ioctl_assemble)
42 #define BCH_IOCTL_INCREMENTAL	_IOW(0xbc, 2, struct bch_ioctl_incremental)
43 
44 struct bch_ioctl_assemble {
45 	__u32			flags;
46 	__u32			nr_devs;
47 	__u64			pad;
48 	__u64			devs[];
49 };
50 
51 struct bch_ioctl_incremental {
52 	__u32			flags;
53 	__u64			pad;
54 	__u64			dev;
55 };
56 #endif
57 
58 /* filesystem ioctls: */
59 
60 #define BCH_IOCTL_QUERY_UUID	_IOR(0xbc,	1,  struct bch_ioctl_query_uuid)
61 
62 /* These only make sense when we also have incremental assembly */
63 #if 0
64 #define BCH_IOCTL_START		_IOW(0xbc,	2,  struct bch_ioctl_start)
65 #define BCH_IOCTL_STOP		_IO(0xbc,	3)
66 #endif
67 
68 #define BCH_IOCTL_DISK_ADD	_IOW(0xbc,	4,  struct bch_ioctl_disk)
69 #define BCH_IOCTL_DISK_REMOVE	_IOW(0xbc,	5,  struct bch_ioctl_disk)
70 #define BCH_IOCTL_DISK_ONLINE	_IOW(0xbc,	6,  struct bch_ioctl_disk)
71 #define BCH_IOCTL_DISK_OFFLINE	_IOW(0xbc,	7,  struct bch_ioctl_disk)
72 #define BCH_IOCTL_DISK_SET_STATE _IOW(0xbc,	8,  struct bch_ioctl_disk_set_state)
73 #define BCH_IOCTL_DATA		_IOW(0xbc,	10, struct bch_ioctl_data)
74 #define BCH_IOCTL_FS_USAGE	_IOWR(0xbc,	11, struct bch_ioctl_fs_usage)
75 #define BCH_IOCTL_DEV_USAGE	_IOWR(0xbc,	11, struct bch_ioctl_dev_usage)
76 #define BCH_IOCTL_READ_SUPER	_IOW(0xbc,	12, struct bch_ioctl_read_super)
77 #define BCH_IOCTL_DISK_GET_IDX	_IOW(0xbc,	13,  struct bch_ioctl_disk_get_idx)
78 #define BCH_IOCTL_DISK_RESIZE	_IOW(0xbc,	14,  struct bch_ioctl_disk_resize)
79 #define BCH_IOCTL_DISK_RESIZE_JOURNAL _IOW(0xbc,15,  struct bch_ioctl_disk_resize_journal)
80 
81 #define BCH_IOCTL_SUBVOLUME_CREATE _IOW(0xbc,	16,  struct bch_ioctl_subvolume)
82 #define BCH_IOCTL_SUBVOLUME_DESTROY _IOW(0xbc,	17,  struct bch_ioctl_subvolume)
83 
84 #define BCH_IOCTL_DEV_USAGE_V2	_IOWR(0xbc,	18, struct bch_ioctl_dev_usage_v2)
85 
86 #define BCH_IOCTL_FSCK_OFFLINE	_IOW(0xbc,	19,  struct bch_ioctl_fsck_offline)
87 #define BCH_IOCTL_FSCK_ONLINE	_IOW(0xbc,	20,  struct bch_ioctl_fsck_online)
88 
89 /* ioctl below act on a particular file, not the filesystem as a whole: */
90 
91 #define BCHFS_IOC_REINHERIT_ATTRS	_IOR(0xbc, 64, const char __user *)
92 
93 /*
94  * BCH_IOCTL_QUERY_UUID: get filesystem UUID
95  *
96  * Returns user visible UUID, not internal UUID (which may not ever be changed);
97  * the filesystem's sysfs directory may be found under /sys/fs/bcachefs with
98  * this UUID.
99  */
100 struct bch_ioctl_query_uuid {
101 	__uuid_t		uuid;
102 };
103 
104 #if 0
105 struct bch_ioctl_start {
106 	__u32			flags;
107 	__u32			pad;
108 };
109 #endif
110 
111 /*
112  * BCH_IOCTL_DISK_ADD: add a new device to an existing filesystem
113  *
114  * The specified device must not be open or in use. On success, the new device
115  * will be an online member of the filesystem just like any other member.
116  *
117  * The device must first be prepared by userspace by formatting with a bcachefs
118  * superblock, which is only used for passing in superblock options/parameters
119  * for that device (in struct bch_member). The new device's superblock should
120  * not claim to be a member of any existing filesystem - UUIDs on it will be
121  * ignored.
122  */
123 
124 /*
125  * BCH_IOCTL_DISK_REMOVE: permanently remove a member device from a filesystem
126  *
127  * Any data present on @dev will be permanently deleted, and @dev will be
128  * removed from its slot in the filesystem's list of member devices. The device
129  * may be either offline or offline.
130  *
131  * Will fail removing @dev would leave us with insufficient read write devices
132  * or degraded/unavailable data, unless the approprate BCH_FORCE_IF_* flags are
133  * set.
134  */
135 
136 /*
137  * BCH_IOCTL_DISK_ONLINE: given a disk that is already a member of a filesystem
138  * but is not open (e.g. because we started in degraded mode), bring it online
139  *
140  * all existing data on @dev will be available once the device is online,
141  * exactly as if @dev was present when the filesystem was first mounted
142  */
143 
144 /*
145  * BCH_IOCTL_DISK_OFFLINE: offline a disk, causing the kernel to close that
146  * block device, without removing it from the filesystem (so it can be brought
147  * back online later)
148  *
149  * Data present on @dev will be unavailable while @dev is offline (unless
150  * replicated), but will still be intact and untouched if @dev is brought back
151  * online
152  *
153  * Will fail (similarly to BCH_IOCTL_DISK_SET_STATE) if offlining @dev would
154  * leave us with insufficient read write devices or degraded/unavailable data,
155  * unless the approprate BCH_FORCE_IF_* flags are set.
156  */
157 
158 struct bch_ioctl_disk {
159 	__u32			flags;
160 	__u32			pad;
161 	__u64			dev;
162 };
163 
164 /*
165  * BCH_IOCTL_DISK_SET_STATE: modify state of a member device of a filesystem
166  *
167  * @new_state		- one of the bch_member_state states (rw, ro, failed,
168  *			  spare)
169  *
170  * Will refuse to change member state if we would then have insufficient devices
171  * to write to, or if it would result in degraded data (when @new_state is
172  * failed or spare) unless the appropriate BCH_FORCE_IF_* flags are set.
173  */
174 struct bch_ioctl_disk_set_state {
175 	__u32			flags;
176 	__u8			new_state;
177 	__u8			pad[3];
178 	__u64			dev;
179 };
180 
181 #define BCH_DATA_OPS()			\
182 	x(scrub,		0)	\
183 	x(rereplicate,		1)	\
184 	x(migrate,		2)	\
185 	x(rewrite_old_nodes,	3)	\
186 	x(drop_extra_replicas,	4)
187 
188 enum bch_data_ops {
189 #define x(t, n) BCH_DATA_OP_##t = n,
190 	BCH_DATA_OPS()
191 #undef x
192 	BCH_DATA_OP_NR
193 };
194 
195 /*
196  * BCH_IOCTL_DATA: operations that walk and manipulate filesystem data (e.g.
197  * scrub, rereplicate, migrate).
198  *
199  * This ioctl kicks off a job in the background, and returns a file descriptor.
200  * Reading from the file descriptor returns a struct bch_ioctl_data_event,
201  * indicating current progress, and closing the file descriptor will stop the
202  * job. The file descriptor is O_CLOEXEC.
203  */
204 struct bch_ioctl_data {
205 	__u16			op;
206 	__u8			start_btree;
207 	__u8			end_btree;
208 	__u32			flags;
209 
210 	struct bpos		start_pos;
211 	struct bpos		end_pos;
212 
213 	union {
214 	struct {
215 		__u32		dev;
216 		__u32		pad;
217 	}			migrate;
218 	struct {
219 		__u64		pad[8];
220 	};
221 	};
222 } __packed __aligned(8);
223 
224 enum bch_data_event {
225 	BCH_DATA_EVENT_PROGRESS	= 0,
226 	/* XXX: add an event for reporting errors */
227 	BCH_DATA_EVENT_NR	= 1,
228 };
229 
230 struct bch_ioctl_data_progress {
231 	__u8			data_type;
232 	__u8			btree_id;
233 	__u8			pad[2];
234 	struct bpos		pos;
235 
236 	__u64			sectors_done;
237 	__u64			sectors_total;
238 } __packed __aligned(8);
239 
240 struct bch_ioctl_data_event {
241 	__u8			type;
242 	__u8			pad[7];
243 	union {
244 	struct bch_ioctl_data_progress p;
245 	__u64			pad2[15];
246 	};
247 } __packed __aligned(8);
248 
249 struct bch_replicas_usage {
250 	__u64			sectors;
251 	struct bch_replicas_entry_v1 r;
252 } __packed;
253 
254 static inline struct bch_replicas_usage *
255 replicas_usage_next(struct bch_replicas_usage *u)
256 {
257 	return (void *) u + replicas_entry_bytes(&u->r) + 8;
258 }
259 
260 /*
261  * BCH_IOCTL_FS_USAGE: query filesystem disk space usage
262  *
263  * Returns disk space usage broken out by data type, number of replicas, and
264  * by component device
265  *
266  * @replica_entries_bytes - size, in bytes, allocated for replica usage entries
267  *
268  * On success, @replica_entries_bytes will be changed to indicate the number of
269  * bytes actually used.
270  *
271  * Returns -ERANGE if @replica_entries_bytes was too small
272  */
273 struct bch_ioctl_fs_usage {
274 	__u64			capacity;
275 	__u64			used;
276 	__u64			online_reserved;
277 	__u64			persistent_reserved[BCH_REPLICAS_MAX];
278 
279 	__u32			replica_entries_bytes;
280 	__u32			pad;
281 
282 	struct bch_replicas_usage replicas[];
283 };
284 
285 /*
286  * BCH_IOCTL_DEV_USAGE: query device disk space usage
287  *
288  * Returns disk space usage broken out by data type - both by buckets and
289  * sectors.
290  */
291 struct bch_ioctl_dev_usage {
292 	__u64			dev;
293 	__u32			flags;
294 	__u8			state;
295 	__u8			pad[7];
296 
297 	__u32			bucket_size;
298 	__u64			nr_buckets;
299 
300 	__u64			buckets_ec;
301 
302 	struct bch_ioctl_dev_usage_type {
303 		__u64		buckets;
304 		__u64		sectors;
305 		__u64		fragmented;
306 	}			d[10];
307 };
308 
309 struct bch_ioctl_dev_usage_v2 {
310 	__u64			dev;
311 	__u32			flags;
312 	__u8			state;
313 	__u8			nr_data_types;
314 	__u8			pad[6];
315 
316 	__u32			bucket_size;
317 	__u64			nr_buckets;
318 
319 	struct bch_ioctl_dev_usage_type d[];
320 };
321 
322 /*
323  * BCH_IOCTL_READ_SUPER: read filesystem superblock
324  *
325  * Equivalent to reading the superblock directly from the block device, except
326  * avoids racing with the kernel writing the superblock or having to figure out
327  * which block device to read
328  *
329  * @sb		- buffer to read into
330  * @size	- size of userspace allocated buffer
331  * @dev		- device to read superblock for, if BCH_READ_DEV flag is
332  *		  specified
333  *
334  * Returns -ERANGE if buffer provided is too small
335  */
336 struct bch_ioctl_read_super {
337 	__u32			flags;
338 	__u32			pad;
339 	__u64			dev;
340 	__u64			size;
341 	__u64			sb;
342 };
343 
344 /*
345  * BCH_IOCTL_DISK_GET_IDX: give a path to a block device, query filesystem to
346  * determine if disk is a (online) member - if so, returns device's index
347  *
348  * Returns -ENOENT if not found
349  */
350 struct bch_ioctl_disk_get_idx {
351 	__u64			dev;
352 };
353 
354 /*
355  * BCH_IOCTL_DISK_RESIZE: resize filesystem on a device
356  *
357  * @dev		- member to resize
358  * @nbuckets	- new number of buckets
359  */
360 struct bch_ioctl_disk_resize {
361 	__u32			flags;
362 	__u32			pad;
363 	__u64			dev;
364 	__u64			nbuckets;
365 };
366 
367 /*
368  * BCH_IOCTL_DISK_RESIZE_JOURNAL: resize journal on a device
369  *
370  * @dev		- member to resize
371  * @nbuckets	- new number of buckets
372  */
373 struct bch_ioctl_disk_resize_journal {
374 	__u32			flags;
375 	__u32			pad;
376 	__u64			dev;
377 	__u64			nbuckets;
378 };
379 
380 struct bch_ioctl_subvolume {
381 	__u32			flags;
382 	__u32			dirfd;
383 	__u16			mode;
384 	__u16			pad[3];
385 	__u64			dst_ptr;
386 	__u64			src_ptr;
387 };
388 
389 #define BCH_SUBVOL_SNAPSHOT_CREATE	(1U << 0)
390 #define BCH_SUBVOL_SNAPSHOT_RO		(1U << 1)
391 
392 /*
393  * BCH_IOCTL_FSCK_OFFLINE: run fsck from the 'bcachefs fsck' userspace command,
394  * but with the kernel's implementation of fsck:
395  */
396 struct bch_ioctl_fsck_offline {
397 	__u64			flags;
398 	__u64			opts;		/* string */
399 	__u64			nr_devs;
400 	__u64			devs[] __counted_by(nr_devs);
401 };
402 
403 /*
404  * BCH_IOCTL_FSCK_ONLINE: run fsck from the 'bcachefs fsck' userspace command,
405  * but with the kernel's implementation of fsck:
406  */
407 struct bch_ioctl_fsck_online {
408 	__u64			flags;
409 	__u64			opts;		/* string */
410 };
411 
412 #endif /* _BCACHEFS_IOCTL_H */
413