1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3 * Filename: target_core_iblock.c
4 *
5 * This file contains the Storage Engine <-> Linux BlockIO transport
6 * specific functions.
7 *
8 * (c) Copyright 2003-2013 Datera, Inc.
9 *
10 * Nicholas A. Bellinger <nab@kernel.org>
11 *
12 ******************************************************************************/
13
14 #include <linux/string.h>
15 #include <linux/parser.h>
16 #include <linux/timer.h>
17 #include <linux/fs.h>
18 #include <linux/blkdev.h>
19 #include <linux/blk-integrity.h>
20 #include <linux/slab.h>
21 #include <linux/spinlock.h>
22 #include <linux/bio.h>
23 #include <linux/file.h>
24 #include <linux/module.h>
25 #include <linux/scatterlist.h>
26 #include <linux/pr.h>
27 #include <scsi/scsi_proto.h>
28 #include <scsi/scsi_common.h>
29 #include <linux/unaligned.h>
30
31 #include <target/target_core_base.h>
32 #include <target/target_core_backend.h>
33
34 #include "target_core_iblock.h"
35 #include "target_core_pr.h"
36
37 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */
38 #define IBLOCK_BIO_POOL_SIZE 128
39
IBLOCK_DEV(struct se_device * dev)40 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev)
41 {
42 return container_of(dev, struct iblock_dev, dev);
43 }
44
45
iblock_attach_hba(struct se_hba * hba,u32 host_id)46 static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
47 {
48 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
49 " Generic Target Core Stack %s\n", hba->hba_id,
50 IBLOCK_VERSION, TARGET_CORE_VERSION);
51 return 0;
52 }
53
iblock_detach_hba(struct se_hba * hba)54 static void iblock_detach_hba(struct se_hba *hba)
55 {
56 }
57
iblock_alloc_device(struct se_hba * hba,const char * name)58 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name)
59 {
60 struct iblock_dev *ib_dev = NULL;
61
62 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
63 if (!ib_dev) {
64 pr_err("Unable to allocate struct iblock_dev\n");
65 return NULL;
66 }
67 ib_dev->ibd_exclusive = true;
68
69 ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug),
70 GFP_KERNEL);
71 if (!ib_dev->ibd_plug)
72 goto free_dev;
73
74 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
75
76 return &ib_dev->dev;
77
78 free_dev:
79 kfree(ib_dev);
80 return NULL;
81 }
82
iblock_configure_unmap(struct se_device * dev)83 static bool iblock_configure_unmap(struct se_device *dev)
84 {
85 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
86
87 return target_configure_unmap_from_bdev(&dev->dev_attrib,
88 ib_dev->ibd_bd);
89 }
90
iblock_configure_device(struct se_device * dev)91 static int iblock_configure_device(struct se_device *dev)
92 {
93 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
94 struct request_queue *q;
95 struct file *bdev_file;
96 struct block_device *bd;
97 struct blk_integrity *bi;
98 blk_mode_t mode = BLK_OPEN_READ;
99 void *holder = ib_dev;
100 unsigned int max_write_zeroes_sectors;
101 int ret;
102
103 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) {
104 pr_err("Missing udev_path= parameters for IBLOCK\n");
105 return -EINVAL;
106 }
107
108 ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
109 if (ret) {
110 pr_err("IBLOCK: Unable to create bioset\n");
111 goto out;
112 }
113
114 pr_debug("IBLOCK: Claiming struct block_device: %s: %d\n",
115 ib_dev->ibd_udev_path, ib_dev->ibd_exclusive);
116
117 if (!ib_dev->ibd_readonly)
118 mode |= BLK_OPEN_WRITE;
119 else
120 dev->dev_flags |= DF_READ_ONLY;
121
122 if (!ib_dev->ibd_exclusive)
123 holder = NULL;
124
125 bdev_file = bdev_file_open_by_path(ib_dev->ibd_udev_path, mode, holder,
126 NULL);
127 if (IS_ERR(bdev_file)) {
128 ret = PTR_ERR(bdev_file);
129 goto out_free_bioset;
130 }
131 ib_dev->ibd_bdev_file = bdev_file;
132 ib_dev->ibd_bd = bd = file_bdev(bdev_file);
133
134 q = bdev_get_queue(bd);
135
136 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
137 dev->dev_attrib.hw_max_sectors = mult_frac(queue_max_hw_sectors(q),
138 SECTOR_SIZE,
139 dev->dev_attrib.hw_block_size);
140 dev->dev_attrib.hw_queue_depth = q->nr_requests;
141
142 /*
143 * Enable write same emulation for IBLOCK and use 0xFFFF as
144 * the smaller WRITE_SAME(10) only has a two-byte block count.
145 */
146 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd);
147 if (max_write_zeroes_sectors)
148 dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors;
149 else
150 dev->dev_attrib.max_write_same_len = 0xFFFF;
151
152 if (bdev_nonrot(bd))
153 dev->dev_attrib.is_nonrot = 1;
154
155 target_configure_write_atomic_from_bdev(&dev->dev_attrib, bd);
156
157 bi = bdev_get_integrity(bd);
158 if (!bi)
159 return 0;
160
161 switch (bi->csum_type) {
162 case BLK_INTEGRITY_CSUM_IP:
163 pr_err("IBLOCK export of blk_integrity: %s not supported\n",
164 blk_integrity_profile_name(bi));
165 ret = -ENOSYS;
166 goto out_blkdev_put;
167 case BLK_INTEGRITY_CSUM_CRC:
168 if (bi->flags & BLK_INTEGRITY_REF_TAG)
169 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT;
170 else
171 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT;
172 break;
173 default:
174 break;
175 }
176
177 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type;
178 return 0;
179
180 out_blkdev_put:
181 fput(ib_dev->ibd_bdev_file);
182 out_free_bioset:
183 bioset_exit(&ib_dev->ibd_bio_set);
184 out:
185 return ret;
186 }
187
iblock_dev_call_rcu(struct rcu_head * p)188 static void iblock_dev_call_rcu(struct rcu_head *p)
189 {
190 struct se_device *dev = container_of(p, struct se_device, rcu_head);
191 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
192
193 kfree(ib_dev->ibd_plug);
194 kfree(ib_dev);
195 }
196
iblock_free_device(struct se_device * dev)197 static void iblock_free_device(struct se_device *dev)
198 {
199 call_rcu(&dev->rcu_head, iblock_dev_call_rcu);
200 }
201
iblock_destroy_device(struct se_device * dev)202 static void iblock_destroy_device(struct se_device *dev)
203 {
204 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
205
206 if (ib_dev->ibd_bdev_file)
207 fput(ib_dev->ibd_bdev_file);
208 bioset_exit(&ib_dev->ibd_bio_set);
209 }
210
iblock_plug_device(struct se_device * se_dev)211 static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev)
212 {
213 struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev);
214 struct iblock_dev_plug *ib_dev_plug;
215
216 /*
217 * Each se_device has a per cpu work this can be run from. We
218 * shouldn't have multiple threads on the same cpu calling this
219 * at the same time.
220 */
221 ib_dev_plug = &ib_dev->ibd_plug[raw_smp_processor_id()];
222 if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags))
223 return NULL;
224
225 blk_start_plug(&ib_dev_plug->blk_plug);
226 return &ib_dev_plug->se_plug;
227 }
228
iblock_unplug_device(struct se_dev_plug * se_plug)229 static void iblock_unplug_device(struct se_dev_plug *se_plug)
230 {
231 struct iblock_dev_plug *ib_dev_plug = container_of(se_plug,
232 struct iblock_dev_plug, se_plug);
233
234 blk_finish_plug(&ib_dev_plug->blk_plug);
235 clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags);
236 }
237
iblock_get_blocks(struct se_device * dev)238 static sector_t iblock_get_blocks(struct se_device *dev)
239 {
240 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
241 u32 block_size = bdev_logical_block_size(ib_dev->ibd_bd);
242 unsigned long long blocks_long =
243 div_u64(bdev_nr_bytes(ib_dev->ibd_bd), block_size) - 1;
244
245 if (block_size == dev->dev_attrib.block_size)
246 return blocks_long;
247
248 switch (block_size) {
249 case 4096:
250 switch (dev->dev_attrib.block_size) {
251 case 2048:
252 blocks_long <<= 1;
253 break;
254 case 1024:
255 blocks_long <<= 2;
256 break;
257 case 512:
258 blocks_long <<= 3;
259 break;
260 default:
261 break;
262 }
263 break;
264 case 2048:
265 switch (dev->dev_attrib.block_size) {
266 case 4096:
267 blocks_long >>= 1;
268 break;
269 case 1024:
270 blocks_long <<= 1;
271 break;
272 case 512:
273 blocks_long <<= 2;
274 break;
275 default:
276 break;
277 }
278 break;
279 case 1024:
280 switch (dev->dev_attrib.block_size) {
281 case 4096:
282 blocks_long >>= 2;
283 break;
284 case 2048:
285 blocks_long >>= 1;
286 break;
287 case 512:
288 blocks_long <<= 1;
289 break;
290 default:
291 break;
292 }
293 break;
294 case 512:
295 switch (dev->dev_attrib.block_size) {
296 case 4096:
297 blocks_long >>= 3;
298 break;
299 case 2048:
300 blocks_long >>= 2;
301 break;
302 case 1024:
303 blocks_long >>= 1;
304 break;
305 default:
306 break;
307 }
308 break;
309 default:
310 break;
311 }
312
313 return blocks_long;
314 }
315
iblock_complete_cmd(struct se_cmd * cmd,blk_status_t blk_status)316 static void iblock_complete_cmd(struct se_cmd *cmd, blk_status_t blk_status)
317 {
318 struct iblock_req *ibr = cmd->priv;
319 u8 status;
320
321 if (!refcount_dec_and_test(&ibr->pending))
322 return;
323
324 if (blk_status == BLK_STS_RESV_CONFLICT)
325 status = SAM_STAT_RESERVATION_CONFLICT;
326 else if (atomic_read(&ibr->ib_bio_err_cnt))
327 status = SAM_STAT_CHECK_CONDITION;
328 else
329 status = SAM_STAT_GOOD;
330
331 target_complete_cmd(cmd, status);
332 kfree(ibr);
333 }
334
iblock_bio_done(struct bio * bio)335 static void iblock_bio_done(struct bio *bio)
336 {
337 struct se_cmd *cmd = bio->bi_private;
338 struct iblock_req *ibr = cmd->priv;
339 blk_status_t blk_status = bio->bi_status;
340
341 if (bio->bi_status) {
342 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status);
343 /*
344 * Bump the ib_bio_err_cnt and release bio.
345 */
346 atomic_inc(&ibr->ib_bio_err_cnt);
347 smp_mb__after_atomic();
348 }
349
350 bio_put(bio);
351
352 iblock_complete_cmd(cmd, blk_status);
353 }
354
iblock_get_bio(struct se_cmd * cmd,sector_t lba,u32 sg_num,blk_opf_t opf)355 static struct bio *iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num,
356 blk_opf_t opf)
357 {
358 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
359 struct bio *bio;
360
361 /*
362 * Only allocate as many vector entries as the bio code allows us to,
363 * we'll loop later on until we have handled the whole request.
364 */
365 bio = bio_alloc_bioset(ib_dev->ibd_bd, bio_max_segs(sg_num), opf,
366 GFP_NOIO, &ib_dev->ibd_bio_set);
367 if (!bio) {
368 pr_err("Unable to allocate memory for bio\n");
369 return NULL;
370 }
371
372 bio->bi_private = cmd;
373 bio->bi_end_io = &iblock_bio_done;
374 bio->bi_iter.bi_sector = lba;
375
376 return bio;
377 }
378
iblock_submit_bios(struct bio_list * list)379 static void iblock_submit_bios(struct bio_list *list)
380 {
381 struct blk_plug plug;
382 struct bio *bio;
383 /*
384 * The block layer handles nested plugs, so just plug/unplug to handle
385 * fabric drivers that didn't support batching and multi bio cmds.
386 */
387 blk_start_plug(&plug);
388 while ((bio = bio_list_pop(list)))
389 submit_bio(bio);
390 blk_finish_plug(&plug);
391 }
392
iblock_end_io_flush(struct bio * bio)393 static void iblock_end_io_flush(struct bio *bio)
394 {
395 struct se_cmd *cmd = bio->bi_private;
396
397 if (bio->bi_status)
398 pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status);
399
400 if (cmd) {
401 if (bio->bi_status)
402 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
403 else
404 target_complete_cmd(cmd, SAM_STAT_GOOD);
405 }
406
407 bio_put(bio);
408 }
409
410 /*
411 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
412 * always flush the whole cache.
413 */
414 static sense_reason_t
iblock_execute_sync_cache(struct se_cmd * cmd)415 iblock_execute_sync_cache(struct se_cmd *cmd)
416 {
417 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
418 int immed = (cmd->t_task_cdb[1] & 0x2);
419 struct bio *bio;
420
421 /*
422 * If the Immediate bit is set, queue up the GOOD response
423 * for this SYNCHRONIZE_CACHE op.
424 */
425 if (immed)
426 target_complete_cmd(cmd, SAM_STAT_GOOD);
427
428 bio = bio_alloc(ib_dev->ibd_bd, 0, REQ_OP_WRITE | REQ_PREFLUSH,
429 GFP_KERNEL);
430 bio->bi_end_io = iblock_end_io_flush;
431 if (!immed)
432 bio->bi_private = cmd;
433 submit_bio(bio);
434 return 0;
435 }
436
437 static sense_reason_t
iblock_execute_unmap(struct se_cmd * cmd,sector_t lba,sector_t nolb)438 iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
439 {
440 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
441 struct se_device *dev = cmd->se_dev;
442 int ret;
443
444 ret = blkdev_issue_discard(bdev,
445 target_to_linux_sector(dev, lba),
446 target_to_linux_sector(dev, nolb),
447 GFP_KERNEL);
448 if (ret < 0) {
449 pr_err("blkdev_issue_discard() failed: %d\n", ret);
450 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
451 }
452
453 return 0;
454 }
455
456 static sense_reason_t
iblock_execute_zero_out(struct block_device * bdev,struct se_cmd * cmd)457 iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd)
458 {
459 struct se_device *dev = cmd->se_dev;
460 struct scatterlist *sg = &cmd->t_data_sg[0];
461 unsigned char *buf, *not_zero;
462 int ret;
463
464 buf = kmap(sg_page(sg)) + sg->offset;
465 if (!buf)
466 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
467 /*
468 * Fall back to block_execute_write_same() slow-path if
469 * incoming WRITE_SAME payload does not contain zeros.
470 */
471 not_zero = memchr_inv(buf, 0x00, cmd->data_length);
472 kunmap(sg_page(sg));
473
474 if (not_zero)
475 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
476
477 ret = blkdev_issue_zeroout(bdev,
478 target_to_linux_sector(dev, cmd->t_task_lba),
479 target_to_linux_sector(dev,
480 sbc_get_write_same_sectors(cmd)),
481 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
482 if (ret)
483 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
484
485 target_complete_cmd(cmd, SAM_STAT_GOOD);
486 return 0;
487 }
488
489 static sense_reason_t
iblock_execute_write_same(struct se_cmd * cmd)490 iblock_execute_write_same(struct se_cmd *cmd)
491 {
492 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
493 struct iblock_req *ibr;
494 struct scatterlist *sg;
495 struct bio *bio;
496 struct bio_list list;
497 struct se_device *dev = cmd->se_dev;
498 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba);
499 sector_t sectors = target_to_linux_sector(dev,
500 sbc_get_write_same_sectors(cmd));
501
502 if (cmd->prot_op) {
503 pr_err("WRITE_SAME: Protection information with IBLOCK"
504 " backends not supported\n");
505 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
506 }
507
508 if (!cmd->t_data_nents)
509 return TCM_INVALID_CDB_FIELD;
510
511 sg = &cmd->t_data_sg[0];
512
513 if (cmd->t_data_nents > 1 ||
514 sg->length != cmd->se_dev->dev_attrib.block_size) {
515 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
516 " block_size: %u\n", cmd->t_data_nents, sg->length,
517 cmd->se_dev->dev_attrib.block_size);
518 return TCM_INVALID_CDB_FIELD;
519 }
520
521 if (bdev_write_zeroes_sectors(bdev)) {
522 if (!iblock_execute_zero_out(bdev, cmd))
523 return 0;
524 }
525
526 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
527 if (!ibr)
528 goto fail;
529 cmd->priv = ibr;
530
531 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE);
532 if (!bio)
533 goto fail_free_ibr;
534
535 bio_list_init(&list);
536 bio_list_add(&list, bio);
537
538 refcount_set(&ibr->pending, 1);
539
540 while (sectors) {
541 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
542 != sg->length) {
543
544 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE);
545 if (!bio)
546 goto fail_put_bios;
547
548 refcount_inc(&ibr->pending);
549 bio_list_add(&list, bio);
550 }
551
552 /* Always in 512 byte units for Linux/Block */
553 block_lba += sg->length >> SECTOR_SHIFT;
554 sectors -= sg->length >> SECTOR_SHIFT;
555 }
556
557 iblock_submit_bios(&list);
558 return 0;
559
560 fail_put_bios:
561 while ((bio = bio_list_pop(&list)))
562 bio_put(bio);
563 fail_free_ibr:
564 kfree(ibr);
565 fail:
566 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
567 }
568
569 enum {
570 Opt_udev_path, Opt_readonly, Opt_force, Opt_exclusive, Opt_err,
571 };
572
573 static match_table_t tokens = {
574 {Opt_udev_path, "udev_path=%s"},
575 {Opt_readonly, "readonly=%d"},
576 {Opt_force, "force=%d"},
577 {Opt_exclusive, "exclusive=%d"},
578 {Opt_err, NULL}
579 };
580
iblock_set_configfs_dev_params(struct se_device * dev,const char * page,ssize_t count)581 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
582 const char *page, ssize_t count)
583 {
584 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
585 char *orig, *ptr, *arg_p, *opts;
586 substring_t args[MAX_OPT_ARGS];
587 int ret = 0, token, tmp_exclusive;
588 unsigned long tmp_readonly;
589
590 opts = kstrdup(page, GFP_KERNEL);
591 if (!opts)
592 return -ENOMEM;
593
594 orig = opts;
595
596 while ((ptr = strsep(&opts, ",\n")) != NULL) {
597 if (!*ptr)
598 continue;
599
600 token = match_token(ptr, tokens, args);
601 switch (token) {
602 case Opt_udev_path:
603 if (ib_dev->ibd_bd) {
604 pr_err("Unable to set udev_path= while"
605 " ib_dev->ibd_bd exists\n");
606 ret = -EEXIST;
607 goto out;
608 }
609 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0],
610 SE_UDEV_PATH_LEN) == 0) {
611 ret = -EINVAL;
612 break;
613 }
614 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
615 ib_dev->ibd_udev_path);
616 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
617 break;
618 case Opt_readonly:
619 arg_p = match_strdup(&args[0]);
620 if (!arg_p) {
621 ret = -ENOMEM;
622 break;
623 }
624 ret = kstrtoul(arg_p, 0, &tmp_readonly);
625 kfree(arg_p);
626 if (ret < 0) {
627 pr_err("kstrtoul() failed for"
628 " readonly=\n");
629 goto out;
630 }
631 ib_dev->ibd_readonly = tmp_readonly;
632 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
633 break;
634 case Opt_exclusive:
635 arg_p = match_strdup(&args[0]);
636 if (!arg_p) {
637 ret = -ENOMEM;
638 break;
639 }
640 ret = kstrtoint(arg_p, 0, &tmp_exclusive);
641 kfree(arg_p);
642 if (ret < 0) {
643 pr_err("kstrtoul() failed for exclusive=\n");
644 goto out;
645 }
646 ib_dev->ibd_exclusive = tmp_exclusive;
647 pr_debug("IBLOCK: exclusive: %d\n",
648 ib_dev->ibd_exclusive);
649 break;
650 case Opt_force:
651 break;
652 default:
653 break;
654 }
655 }
656
657 out:
658 kfree(orig);
659 return (!ret) ? count : ret;
660 }
661
iblock_show_configfs_dev_params(struct se_device * dev,char * b)662 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
663 {
664 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
665 struct block_device *bd = ib_dev->ibd_bd;
666 ssize_t bl = 0;
667
668 if (bd)
669 bl += sprintf(b + bl, "iBlock device: %pg", bd);
670 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
671 bl += sprintf(b + bl, " UDEV PATH: %s",
672 ib_dev->ibd_udev_path);
673 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly);
674 bl += sprintf(b + bl, " exclusive: %d\n", ib_dev->ibd_exclusive);
675
676 bl += sprintf(b + bl, " ");
677 if (bd) {
678 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
679 MAJOR(bd->bd_dev), MINOR(bd->bd_dev),
680 "CLAIMED: IBLOCK");
681 } else {
682 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
683 }
684
685 return bl;
686 }
687
688 static int
iblock_alloc_bip(struct se_cmd * cmd,struct bio * bio,struct sg_mapping_iter * miter)689 iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio,
690 struct sg_mapping_iter *miter)
691 {
692 struct se_device *dev = cmd->se_dev;
693 struct blk_integrity *bi;
694 struct bio_integrity_payload *bip;
695 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
696 int rc;
697 size_t resid, len;
698
699 bi = bdev_get_integrity(ib_dev->ibd_bd);
700 if (!bi) {
701 pr_err("Unable to locate bio_integrity\n");
702 return -ENODEV;
703 }
704
705 bip = bio_integrity_alloc(bio, GFP_NOIO, bio_max_segs(cmd->t_prot_nents));
706 if (IS_ERR(bip)) {
707 pr_err("Unable to allocate bio_integrity_payload\n");
708 return PTR_ERR(bip);
709 }
710
711 /* virtual start sector must be in integrity interval units */
712 bip_set_seed(bip, bio->bi_iter.bi_sector >>
713 (bi->interval_exp - SECTOR_SHIFT));
714
715 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size,
716 (unsigned long long)bip->bip_iter.bi_sector);
717
718 resid = bio_integrity_bytes(bi, bio_sectors(bio));
719 while (resid > 0 && sg_miter_next(miter)) {
720
721 len = min_t(size_t, miter->length, resid);
722 rc = bio_integrity_add_page(bio, miter->page, len,
723 offset_in_page(miter->addr));
724 if (rc != len) {
725 pr_err("bio_integrity_add_page() failed; %d\n", rc);
726 sg_miter_stop(miter);
727 return -ENOMEM;
728 }
729
730 pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n",
731 miter->page, len, offset_in_page(miter->addr));
732
733 resid -= len;
734 if (len < miter->length)
735 miter->consumed -= miter->length - len;
736 }
737 sg_miter_stop(miter);
738
739 return 0;
740 }
741
742 static sense_reason_t
iblock_execute_rw(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)743 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
744 enum dma_data_direction data_direction)
745 {
746 struct se_device *dev = cmd->se_dev;
747 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba);
748 struct iblock_req *ibr;
749 struct bio *bio;
750 struct bio_list list;
751 struct scatterlist *sg;
752 u32 sg_num = sgl_nents;
753 blk_opf_t opf;
754 unsigned bio_cnt;
755 int i, rc;
756 struct sg_mapping_iter prot_miter;
757 unsigned int miter_dir;
758
759 if (data_direction == DMA_TO_DEVICE) {
760 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
761
762 /*
763 * Set bits to indicate WRITE_ODIRECT so we are not throttled
764 * by WBT.
765 */
766 opf = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
767 /*
768 * Force writethrough using REQ_FUA if a volatile write cache
769 * is not enabled, or if initiator set the Force Unit Access bit.
770 */
771 miter_dir = SG_MITER_TO_SG;
772 if (bdev_fua(ib_dev->ibd_bd)) {
773 if (cmd->se_cmd_flags & SCF_FUA)
774 opf |= REQ_FUA;
775 else if (!bdev_write_cache(ib_dev->ibd_bd))
776 opf |= REQ_FUA;
777 }
778
779 if (cmd->se_cmd_flags & SCF_ATOMIC)
780 opf |= REQ_ATOMIC;
781 } else {
782 opf = REQ_OP_READ;
783 miter_dir = SG_MITER_FROM_SG;
784 }
785
786 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
787 if (!ibr)
788 goto fail;
789 cmd->priv = ibr;
790
791 if (!sgl_nents) {
792 refcount_set(&ibr->pending, 1);
793 iblock_complete_cmd(cmd, BLK_STS_OK);
794 return 0;
795 }
796
797 bio = iblock_get_bio(cmd, block_lba, sgl_nents, opf);
798 if (!bio)
799 goto fail_free_ibr;
800
801 bio_list_init(&list);
802 bio_list_add(&list, bio);
803
804 refcount_set(&ibr->pending, 2);
805 bio_cnt = 1;
806
807 if (cmd->prot_type && dev->dev_attrib.pi_prot_type)
808 sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents,
809 miter_dir);
810
811 for_each_sg(sgl, sg, sgl_nents, i) {
812 /*
813 * XXX: if the length the device accepts is shorter than the
814 * length of the S/G list entry this will cause and
815 * endless loop. Better hope no driver uses huge pages.
816 */
817 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
818 != sg->length) {
819 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
820 rc = iblock_alloc_bip(cmd, bio, &prot_miter);
821 if (rc)
822 goto fail_put_bios;
823 }
824
825 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
826 iblock_submit_bios(&list);
827 bio_cnt = 0;
828 }
829
830 bio = iblock_get_bio(cmd, block_lba, sg_num, opf);
831 if (!bio)
832 goto fail_put_bios;
833
834 refcount_inc(&ibr->pending);
835 bio_list_add(&list, bio);
836 bio_cnt++;
837 }
838
839 /* Always in 512 byte units for Linux/Block */
840 block_lba += sg->length >> SECTOR_SHIFT;
841 sg_num--;
842 }
843
844 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
845 rc = iblock_alloc_bip(cmd, bio, &prot_miter);
846 if (rc)
847 goto fail_put_bios;
848 }
849
850 iblock_submit_bios(&list);
851 iblock_complete_cmd(cmd, BLK_STS_OK);
852 return 0;
853
854 fail_put_bios:
855 while ((bio = bio_list_pop(&list)))
856 bio_put(bio);
857 fail_free_ibr:
858 kfree(ibr);
859 fail:
860 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
861 }
862
iblock_execute_pr_out(struct se_cmd * cmd,u8 sa,u64 key,u64 sa_key,u8 type,bool aptpl)863 static sense_reason_t iblock_execute_pr_out(struct se_cmd *cmd, u8 sa, u64 key,
864 u64 sa_key, u8 type, bool aptpl)
865 {
866 struct se_device *dev = cmd->se_dev;
867 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
868 struct block_device *bdev = ib_dev->ibd_bd;
869 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
870 int ret;
871
872 if (!ops) {
873 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
874 return TCM_UNSUPPORTED_SCSI_OPCODE;
875 }
876
877 switch (sa) {
878 case PRO_REGISTER:
879 case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
880 if (!ops->pr_register) {
881 pr_err("block device does not support pr_register.\n");
882 return TCM_UNSUPPORTED_SCSI_OPCODE;
883 }
884
885 /* The block layer pr ops always enables aptpl */
886 if (!aptpl)
887 pr_info("APTPL not set by initiator, but will be used.\n");
888
889 ret = ops->pr_register(bdev, key, sa_key,
890 sa == PRO_REGISTER ? 0 : PR_FL_IGNORE_KEY);
891 break;
892 case PRO_RESERVE:
893 if (!ops->pr_reserve) {
894 pr_err("block_device does not support pr_reserve.\n");
895 return TCM_UNSUPPORTED_SCSI_OPCODE;
896 }
897
898 ret = ops->pr_reserve(bdev, key, scsi_pr_type_to_block(type), 0);
899 break;
900 case PRO_CLEAR:
901 if (!ops->pr_clear) {
902 pr_err("block_device does not support pr_clear.\n");
903 return TCM_UNSUPPORTED_SCSI_OPCODE;
904 }
905
906 ret = ops->pr_clear(bdev, key);
907 break;
908 case PRO_PREEMPT:
909 case PRO_PREEMPT_AND_ABORT:
910 if (!ops->pr_clear) {
911 pr_err("block_device does not support pr_preempt.\n");
912 return TCM_UNSUPPORTED_SCSI_OPCODE;
913 }
914
915 ret = ops->pr_preempt(bdev, key, sa_key,
916 scsi_pr_type_to_block(type),
917 sa == PRO_PREEMPT_AND_ABORT);
918 break;
919 case PRO_RELEASE:
920 if (!ops->pr_clear) {
921 pr_err("block_device does not support pr_pclear.\n");
922 return TCM_UNSUPPORTED_SCSI_OPCODE;
923 }
924
925 ret = ops->pr_release(bdev, key, scsi_pr_type_to_block(type));
926 break;
927 default:
928 pr_err("Unknown PERSISTENT_RESERVE_OUT SA: 0x%02x\n", sa);
929 return TCM_UNSUPPORTED_SCSI_OPCODE;
930 }
931
932 if (!ret)
933 return TCM_NO_SENSE;
934 else if (ret == PR_STS_RESERVATION_CONFLICT)
935 return TCM_RESERVATION_CONFLICT;
936 else
937 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
938 }
939
iblock_pr_report_caps(unsigned char * param_data)940 static void iblock_pr_report_caps(unsigned char *param_data)
941 {
942 u16 len = 8;
943
944 put_unaligned_be16(len, ¶m_data[0]);
945 /*
946 * When using the pr_ops passthrough method we only support exporting
947 * the device through one target port because from the backend module
948 * level we can't see the target port config. As a result we only
949 * support registration directly from the I_T nexus the cmd is sent
950 * through and do not set ATP_C here.
951 *
952 * The block layer pr_ops do not support passing in initiators so
953 * we don't set SIP_C here.
954 */
955 /* PTPL_C: Persistence across Target Power Loss bit */
956 param_data[2] |= 0x01;
957 /*
958 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
959 * set the TMV: Task Mask Valid bit.
960 */
961 param_data[3] |= 0x80;
962 /*
963 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
964 */
965 param_data[3] |= 0x10; /* ALLOW COMMANDs field 001b */
966 /*
967 * PTPL_A: Persistence across Target Power Loss Active bit. The block
968 * layer pr ops always enables this so report it active.
969 */
970 param_data[3] |= 0x01;
971 /*
972 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 212 spc4r37.
973 */
974 param_data[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
975 param_data[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
976 param_data[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
977 param_data[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
978 param_data[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
979 param_data[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
980 }
981
iblock_pr_read_keys(struct se_cmd * cmd,unsigned char * param_data)982 static sense_reason_t iblock_pr_read_keys(struct se_cmd *cmd,
983 unsigned char *param_data)
984 {
985 struct se_device *dev = cmd->se_dev;
986 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
987 struct block_device *bdev = ib_dev->ibd_bd;
988 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
989 int i, len, paths, data_offset;
990 struct pr_keys *keys;
991 sense_reason_t ret;
992
993 if (!ops) {
994 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
995 return TCM_UNSUPPORTED_SCSI_OPCODE;
996 }
997
998 if (!ops->pr_read_keys) {
999 pr_err("Block device does not support read_keys.\n");
1000 return TCM_UNSUPPORTED_SCSI_OPCODE;
1001 }
1002
1003 /*
1004 * We don't know what's under us, but dm-multipath will register every
1005 * path with the same key, so start off with enough space for 16 paths.
1006 * which is not a lot of memory and should normally be enough.
1007 */
1008 paths = 16;
1009 retry:
1010 len = 8 * paths;
1011 keys = kzalloc(sizeof(*keys) + len, GFP_KERNEL);
1012 if (!keys)
1013 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1014
1015 keys->num_keys = paths;
1016 if (!ops->pr_read_keys(bdev, keys)) {
1017 if (keys->num_keys > paths) {
1018 kfree(keys);
1019 paths *= 2;
1020 goto retry;
1021 }
1022 } else {
1023 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1024 goto free_keys;
1025 }
1026
1027 ret = TCM_NO_SENSE;
1028
1029 put_unaligned_be32(keys->generation, ¶m_data[0]);
1030 if (!keys->num_keys) {
1031 put_unaligned_be32(0, ¶m_data[4]);
1032 goto free_keys;
1033 }
1034
1035 put_unaligned_be32(8 * keys->num_keys, ¶m_data[4]);
1036
1037 data_offset = 8;
1038 for (i = 0; i < keys->num_keys; i++) {
1039 if (data_offset + 8 > cmd->data_length)
1040 break;
1041
1042 put_unaligned_be64(keys->keys[i], ¶m_data[data_offset]);
1043 data_offset += 8;
1044 }
1045
1046 free_keys:
1047 kfree(keys);
1048 return ret;
1049 }
1050
iblock_pr_read_reservation(struct se_cmd * cmd,unsigned char * param_data)1051 static sense_reason_t iblock_pr_read_reservation(struct se_cmd *cmd,
1052 unsigned char *param_data)
1053 {
1054 struct se_device *dev = cmd->se_dev;
1055 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1056 struct block_device *bdev = ib_dev->ibd_bd;
1057 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
1058 struct pr_held_reservation rsv = { };
1059
1060 if (!ops) {
1061 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
1062 return TCM_UNSUPPORTED_SCSI_OPCODE;
1063 }
1064
1065 if (!ops->pr_read_reservation) {
1066 pr_err("Block device does not support read_keys.\n");
1067 return TCM_UNSUPPORTED_SCSI_OPCODE;
1068 }
1069
1070 if (ops->pr_read_reservation(bdev, &rsv))
1071 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1072
1073 put_unaligned_be32(rsv.generation, ¶m_data[0]);
1074 if (!block_pr_type_to_scsi(rsv.type)) {
1075 put_unaligned_be32(0, ¶m_data[4]);
1076 return TCM_NO_SENSE;
1077 }
1078
1079 put_unaligned_be32(16, ¶m_data[4]);
1080
1081 if (cmd->data_length < 16)
1082 return TCM_NO_SENSE;
1083 put_unaligned_be64(rsv.key, ¶m_data[8]);
1084
1085 if (cmd->data_length < 22)
1086 return TCM_NO_SENSE;
1087 param_data[21] = block_pr_type_to_scsi(rsv.type);
1088
1089 return TCM_NO_SENSE;
1090 }
1091
iblock_execute_pr_in(struct se_cmd * cmd,u8 sa,unsigned char * param_data)1092 static sense_reason_t iblock_execute_pr_in(struct se_cmd *cmd, u8 sa,
1093 unsigned char *param_data)
1094 {
1095 sense_reason_t ret = TCM_NO_SENSE;
1096
1097 switch (sa) {
1098 case PRI_REPORT_CAPABILITIES:
1099 iblock_pr_report_caps(param_data);
1100 break;
1101 case PRI_READ_KEYS:
1102 ret = iblock_pr_read_keys(cmd, param_data);
1103 break;
1104 case PRI_READ_RESERVATION:
1105 ret = iblock_pr_read_reservation(cmd, param_data);
1106 break;
1107 default:
1108 pr_err("Unknown PERSISTENT_RESERVE_IN SA: 0x%02x\n", sa);
1109 return TCM_UNSUPPORTED_SCSI_OPCODE;
1110 }
1111
1112 return ret;
1113 }
1114
iblock_get_alignment_offset_lbas(struct se_device * dev)1115 static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev)
1116 {
1117 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1118 struct block_device *bd = ib_dev->ibd_bd;
1119 int ret;
1120
1121 ret = bdev_alignment_offset(bd);
1122 if (ret == -1)
1123 return 0;
1124
1125 /* convert offset-bytes to offset-lbas */
1126 return ret / bdev_logical_block_size(bd);
1127 }
1128
iblock_get_lbppbe(struct se_device * dev)1129 static unsigned int iblock_get_lbppbe(struct se_device *dev)
1130 {
1131 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1132 struct block_device *bd = ib_dev->ibd_bd;
1133 unsigned int logs_per_phys =
1134 bdev_physical_block_size(bd) / bdev_logical_block_size(bd);
1135
1136 return ilog2(logs_per_phys);
1137 }
1138
iblock_get_io_min(struct se_device * dev)1139 static unsigned int iblock_get_io_min(struct se_device *dev)
1140 {
1141 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1142 struct block_device *bd = ib_dev->ibd_bd;
1143
1144 return bdev_io_min(bd);
1145 }
1146
iblock_get_io_opt(struct se_device * dev)1147 static unsigned int iblock_get_io_opt(struct se_device *dev)
1148 {
1149 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1150 struct block_device *bd = ib_dev->ibd_bd;
1151
1152 return bdev_io_opt(bd);
1153 }
1154
1155 static struct exec_cmd_ops iblock_exec_cmd_ops = {
1156 .execute_rw = iblock_execute_rw,
1157 .execute_sync_cache = iblock_execute_sync_cache,
1158 .execute_write_same = iblock_execute_write_same,
1159 .execute_unmap = iblock_execute_unmap,
1160 .execute_pr_out = iblock_execute_pr_out,
1161 .execute_pr_in = iblock_execute_pr_in,
1162 };
1163
1164 static sense_reason_t
iblock_parse_cdb(struct se_cmd * cmd)1165 iblock_parse_cdb(struct se_cmd *cmd)
1166 {
1167 return sbc_parse_cdb(cmd, &iblock_exec_cmd_ops);
1168 }
1169
iblock_get_write_cache(struct se_device * dev)1170 static bool iblock_get_write_cache(struct se_device *dev)
1171 {
1172 return bdev_write_cache(IBLOCK_DEV(dev)->ibd_bd);
1173 }
1174
1175 static const struct target_backend_ops iblock_ops = {
1176 .name = "iblock",
1177 .inquiry_prod = "IBLOCK",
1178 .transport_flags_changeable = TRANSPORT_FLAG_PASSTHROUGH_PGR,
1179 .inquiry_rev = IBLOCK_VERSION,
1180 .owner = THIS_MODULE,
1181 .attach_hba = iblock_attach_hba,
1182 .detach_hba = iblock_detach_hba,
1183 .alloc_device = iblock_alloc_device,
1184 .configure_device = iblock_configure_device,
1185 .destroy_device = iblock_destroy_device,
1186 .free_device = iblock_free_device,
1187 .configure_unmap = iblock_configure_unmap,
1188 .plug_device = iblock_plug_device,
1189 .unplug_device = iblock_unplug_device,
1190 .parse_cdb = iblock_parse_cdb,
1191 .set_configfs_dev_params = iblock_set_configfs_dev_params,
1192 .show_configfs_dev_params = iblock_show_configfs_dev_params,
1193 .get_device_type = sbc_get_device_type,
1194 .get_blocks = iblock_get_blocks,
1195 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas,
1196 .get_lbppbe = iblock_get_lbppbe,
1197 .get_io_min = iblock_get_io_min,
1198 .get_io_opt = iblock_get_io_opt,
1199 .get_write_cache = iblock_get_write_cache,
1200 .tb_dev_attrib_attrs = sbc_attrib_attrs,
1201 };
1202
iblock_module_init(void)1203 static int __init iblock_module_init(void)
1204 {
1205 return transport_backend_register(&iblock_ops);
1206 }
1207
iblock_module_exit(void)1208 static void __exit iblock_module_exit(void)
1209 {
1210 target_backend_unregister(&iblock_ops);
1211 }
1212
1213 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
1214 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1215 MODULE_LICENSE("GPL");
1216
1217 module_init(iblock_module_init);
1218 module_exit(iblock_module_exit);
1219