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Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[deliverable/linux.git] / drivers / target / target_core_iblock.c
1 /*******************************************************************************
2 * Filename: target_core_iblock.c
3 *
4 * This file contains the Storage Engine <-> Linux BlockIO transport
5 * specific functions.
6 *
7 * Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
8 * Copyright (c) 2005, 2006, 2007 SBE, Inc.
9 * Copyright (c) 2007-2010 Rising Tide Systems
10 * Copyright (c) 2008-2010 Linux-iSCSI.org
11 *
12 * Nicholas A. Bellinger <nab@kernel.org>
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software
26 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 *
28 ******************************************************************************/
29
30 #include <linux/string.h>
31 #include <linux/parser.h>
32 #include <linux/timer.h>
33 #include <linux/fs.h>
34 #include <linux/blkdev.h>
35 #include <linux/slab.h>
36 #include <linux/spinlock.h>
37 #include <linux/bio.h>
38 #include <linux/genhd.h>
39 #include <linux/file.h>
40 #include <linux/module.h>
41 #include <scsi/scsi.h>
42 #include <scsi/scsi_host.h>
43 #include <asm/unaligned.h>
44
45 #include <target/target_core_base.h>
46 #include <target/target_core_backend.h>
47
48 #include "target_core_iblock.h"
49
50 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */
51 #define IBLOCK_BIO_POOL_SIZE 128
52
53 static struct se_subsystem_api iblock_template;
54
55 static void iblock_bio_done(struct bio *, int);
56
57 /* iblock_attach_hba(): (Part of se_subsystem_api_t template)
58 *
59 *
60 */
61 static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
62 {
63 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
64 " Generic Target Core Stack %s\n", hba->hba_id,
65 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
66 return 0;
67 }
68
69 static void iblock_detach_hba(struct se_hba *hba)
70 {
71 }
72
73 static void *iblock_allocate_virtdevice(struct se_hba *hba, const char *name)
74 {
75 struct iblock_dev *ib_dev = NULL;
76
77 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
78 if (!ib_dev) {
79 pr_err("Unable to allocate struct iblock_dev\n");
80 return NULL;
81 }
82
83 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
84
85 return ib_dev;
86 }
87
88 static struct se_device *iblock_create_virtdevice(
89 struct se_hba *hba,
90 struct se_subsystem_dev *se_dev,
91 void *p)
92 {
93 struct iblock_dev *ib_dev = p;
94 struct se_device *dev;
95 struct se_dev_limits dev_limits;
96 struct block_device *bd = NULL;
97 struct request_queue *q;
98 struct queue_limits *limits;
99 u32 dev_flags = 0;
100 fmode_t mode;
101 int ret = -EINVAL;
102
103 if (!ib_dev) {
104 pr_err("Unable to locate struct iblock_dev parameter\n");
105 return ERR_PTR(ret);
106 }
107 memset(&dev_limits, 0, sizeof(struct se_dev_limits));
108
109 ib_dev->ibd_bio_set = bioset_create(IBLOCK_BIO_POOL_SIZE, 0);
110 if (!ib_dev->ibd_bio_set) {
111 pr_err("IBLOCK: Unable to create bioset()\n");
112 return ERR_PTR(-ENOMEM);
113 }
114 pr_debug("IBLOCK: Created bio_set()\n");
115 /*
116 * iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path
117 * must already have been set in order for echo 1 > $HBA/$DEV/enable to run.
118 */
119 pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
120 ib_dev->ibd_udev_path);
121
122 mode = FMODE_READ|FMODE_EXCL;
123 if (!ib_dev->ibd_readonly)
124 mode |= FMODE_WRITE;
125
126 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev);
127 if (IS_ERR(bd)) {
128 ret = PTR_ERR(bd);
129 goto failed;
130 }
131 /*
132 * Setup the local scope queue_limits from struct request_queue->limits
133 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
134 */
135 q = bdev_get_queue(bd);
136 limits = &dev_limits.limits;
137 limits->logical_block_size = bdev_logical_block_size(bd);
138 limits->max_hw_sectors = UINT_MAX;
139 limits->max_sectors = UINT_MAX;
140 dev_limits.hw_queue_depth = q->nr_requests;
141 dev_limits.queue_depth = q->nr_requests;
142
143 ib_dev->ibd_bd = bd;
144
145 dev = transport_add_device_to_core_hba(hba,
146 &iblock_template, se_dev, dev_flags, ib_dev,
147 &dev_limits, "IBLOCK", IBLOCK_VERSION);
148 if (!dev)
149 goto failed;
150
151 /*
152 * Check if the underlying struct block_device request_queue supports
153 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
154 * in ATA and we need to set TPE=1
155 */
156 if (blk_queue_discard(q)) {
157 dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count =
158 q->limits.max_discard_sectors;
159 /*
160 * Currently hardcoded to 1 in Linux/SCSI code..
161 */
162 dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count = 1;
163 dev->se_sub_dev->se_dev_attrib.unmap_granularity =
164 q->limits.discard_granularity >> 9;
165 dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment =
166 q->limits.discard_alignment;
167
168 pr_debug("IBLOCK: BLOCK Discard support available,"
169 " disabled by default\n");
170 }
171
172 if (blk_queue_nonrot(q))
173 dev->se_sub_dev->se_dev_attrib.is_nonrot = 1;
174
175 return dev;
176
177 failed:
178 if (ib_dev->ibd_bio_set) {
179 bioset_free(ib_dev->ibd_bio_set);
180 ib_dev->ibd_bio_set = NULL;
181 }
182 ib_dev->ibd_bd = NULL;
183 return ERR_PTR(ret);
184 }
185
186 static void iblock_free_device(void *p)
187 {
188 struct iblock_dev *ib_dev = p;
189
190 if (ib_dev->ibd_bd != NULL)
191 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
192 if (ib_dev->ibd_bio_set != NULL)
193 bioset_free(ib_dev->ibd_bio_set);
194 kfree(ib_dev);
195 }
196
197 static unsigned long long iblock_emulate_read_cap_with_block_size(
198 struct se_device *dev,
199 struct block_device *bd,
200 struct request_queue *q)
201 {
202 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
203 bdev_logical_block_size(bd)) - 1);
204 u32 block_size = bdev_logical_block_size(bd);
205
206 if (block_size == dev->se_sub_dev->se_dev_attrib.block_size)
207 return blocks_long;
208
209 switch (block_size) {
210 case 4096:
211 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
212 case 2048:
213 blocks_long <<= 1;
214 break;
215 case 1024:
216 blocks_long <<= 2;
217 break;
218 case 512:
219 blocks_long <<= 3;
220 default:
221 break;
222 }
223 break;
224 case 2048:
225 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
226 case 4096:
227 blocks_long >>= 1;
228 break;
229 case 1024:
230 blocks_long <<= 1;
231 break;
232 case 512:
233 blocks_long <<= 2;
234 break;
235 default:
236 break;
237 }
238 break;
239 case 1024:
240 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
241 case 4096:
242 blocks_long >>= 2;
243 break;
244 case 2048:
245 blocks_long >>= 1;
246 break;
247 case 512:
248 blocks_long <<= 1;
249 break;
250 default:
251 break;
252 }
253 break;
254 case 512:
255 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
256 case 4096:
257 blocks_long >>= 3;
258 break;
259 case 2048:
260 blocks_long >>= 2;
261 break;
262 case 1024:
263 blocks_long >>= 1;
264 break;
265 default:
266 break;
267 }
268 break;
269 default:
270 break;
271 }
272
273 return blocks_long;
274 }
275
276 static void iblock_end_io_flush(struct bio *bio, int err)
277 {
278 struct se_cmd *cmd = bio->bi_private;
279
280 if (err)
281 pr_err("IBLOCK: cache flush failed: %d\n", err);
282
283 if (cmd) {
284 if (err) {
285 cmd->scsi_sense_reason =
286 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
287 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
288 } else {
289 target_complete_cmd(cmd, SAM_STAT_GOOD);
290 }
291 }
292
293 bio_put(bio);
294 }
295
296 /*
297 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
298 * always flush the whole cache.
299 */
300 static int iblock_execute_sync_cache(struct se_cmd *cmd)
301 {
302 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
303 int immed = (cmd->t_task_cdb[1] & 0x2);
304 struct bio *bio;
305
306 /*
307 * If the Immediate bit is set, queue up the GOOD response
308 * for this SYNCHRONIZE_CACHE op.
309 */
310 if (immed)
311 target_complete_cmd(cmd, SAM_STAT_GOOD);
312
313 bio = bio_alloc(GFP_KERNEL, 0);
314 bio->bi_end_io = iblock_end_io_flush;
315 bio->bi_bdev = ib_dev->ibd_bd;
316 if (!immed)
317 bio->bi_private = cmd;
318 submit_bio(WRITE_FLUSH, bio);
319 return 0;
320 }
321
322 static int iblock_execute_unmap(struct se_cmd *cmd)
323 {
324 struct se_device *dev = cmd->se_dev;
325 struct iblock_dev *ibd = dev->dev_ptr;
326 unsigned char *buf, *ptr = NULL;
327 sector_t lba;
328 int size = cmd->data_length;
329 u32 range;
330 int ret = 0;
331 int dl, bd_dl;
332
333 buf = transport_kmap_data_sg(cmd);
334
335 dl = get_unaligned_be16(&buf[0]);
336 bd_dl = get_unaligned_be16(&buf[2]);
337
338 size = min(size - 8, bd_dl);
339 if (size / 16 > dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count) {
340 cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
341 ret = -EINVAL;
342 goto err;
343 }
344
345 /* First UNMAP block descriptor starts at 8 byte offset */
346 ptr = &buf[8];
347 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
348 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
349
350 while (size >= 16) {
351 lba = get_unaligned_be64(&ptr[0]);
352 range = get_unaligned_be32(&ptr[8]);
353 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
354 (unsigned long long)lba, range);
355
356 if (range > dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count) {
357 cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
358 ret = -EINVAL;
359 goto err;
360 }
361
362 if (lba + range > dev->transport->get_blocks(dev) + 1) {
363 cmd->scsi_sense_reason = TCM_ADDRESS_OUT_OF_RANGE;
364 ret = -EINVAL;
365 goto err;
366 }
367
368 ret = blkdev_issue_discard(ibd->ibd_bd, lba, range,
369 GFP_KERNEL, 0);
370 if (ret < 0) {
371 pr_err("blkdev_issue_discard() failed: %d\n",
372 ret);
373 goto err;
374 }
375
376 ptr += 16;
377 size -= 16;
378 }
379
380 err:
381 transport_kunmap_data_sg(cmd);
382 if (!ret)
383 target_complete_cmd(cmd, GOOD);
384 return ret;
385 }
386
387 static int iblock_execute_write_same(struct se_cmd *cmd)
388 {
389 struct iblock_dev *ibd = cmd->se_dev->dev_ptr;
390 int ret;
391
392 ret = blkdev_issue_discard(ibd->ibd_bd, cmd->t_task_lba,
393 spc_get_write_same_sectors(cmd), GFP_KERNEL,
394 0);
395 if (ret < 0) {
396 pr_debug("blkdev_issue_discard() failed for WRITE_SAME\n");
397 return ret;
398 }
399
400 target_complete_cmd(cmd, GOOD);
401 return 0;
402 }
403
404 enum {
405 Opt_udev_path, Opt_readonly, Opt_force, Opt_err
406 };
407
408 static match_table_t tokens = {
409 {Opt_udev_path, "udev_path=%s"},
410 {Opt_readonly, "readonly=%d"},
411 {Opt_force, "force=%d"},
412 {Opt_err, NULL}
413 };
414
415 static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
416 struct se_subsystem_dev *se_dev,
417 const char *page, ssize_t count)
418 {
419 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr;
420 char *orig, *ptr, *arg_p, *opts;
421 substring_t args[MAX_OPT_ARGS];
422 int ret = 0, token;
423 unsigned long tmp_readonly;
424
425 opts = kstrdup(page, GFP_KERNEL);
426 if (!opts)
427 return -ENOMEM;
428
429 orig = opts;
430
431 while ((ptr = strsep(&opts, ",\n")) != NULL) {
432 if (!*ptr)
433 continue;
434
435 token = match_token(ptr, tokens, args);
436 switch (token) {
437 case Opt_udev_path:
438 if (ib_dev->ibd_bd) {
439 pr_err("Unable to set udev_path= while"
440 " ib_dev->ibd_bd exists\n");
441 ret = -EEXIST;
442 goto out;
443 }
444 arg_p = match_strdup(&args[0]);
445 if (!arg_p) {
446 ret = -ENOMEM;
447 break;
448 }
449 snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
450 "%s", arg_p);
451 kfree(arg_p);
452 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
453 ib_dev->ibd_udev_path);
454 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
455 break;
456 case Opt_readonly:
457 arg_p = match_strdup(&args[0]);
458 if (!arg_p) {
459 ret = -ENOMEM;
460 break;
461 }
462 ret = strict_strtoul(arg_p, 0, &tmp_readonly);
463 kfree(arg_p);
464 if (ret < 0) {
465 pr_err("strict_strtoul() failed for"
466 " readonly=\n");
467 goto out;
468 }
469 ib_dev->ibd_readonly = tmp_readonly;
470 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
471 break;
472 case Opt_force:
473 break;
474 default:
475 break;
476 }
477 }
478
479 out:
480 kfree(orig);
481 return (!ret) ? count : ret;
482 }
483
484 static ssize_t iblock_check_configfs_dev_params(
485 struct se_hba *hba,
486 struct se_subsystem_dev *se_dev)
487 {
488 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
489
490 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) {
491 pr_err("Missing udev_path= parameters for IBLOCK\n");
492 return -EINVAL;
493 }
494
495 return 0;
496 }
497
498 static ssize_t iblock_show_configfs_dev_params(
499 struct se_hba *hba,
500 struct se_subsystem_dev *se_dev,
501 char *b)
502 {
503 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
504 struct block_device *bd = ibd->ibd_bd;
505 char buf[BDEVNAME_SIZE];
506 ssize_t bl = 0;
507
508 if (bd)
509 bl += sprintf(b + bl, "iBlock device: %s",
510 bdevname(bd, buf));
511 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH)
512 bl += sprintf(b + bl, " UDEV PATH: %s",
513 ibd->ibd_udev_path);
514 bl += sprintf(b + bl, " readonly: %d\n", ibd->ibd_readonly);
515
516 bl += sprintf(b + bl, " ");
517 if (bd) {
518 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
519 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
520 "" : (bd->bd_holder == ibd) ?
521 "CLAIMED: IBLOCK" : "CLAIMED: OS");
522 } else {
523 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
524 }
525
526 return bl;
527 }
528
529 static void iblock_complete_cmd(struct se_cmd *cmd)
530 {
531 struct iblock_req *ibr = cmd->priv;
532 u8 status;
533
534 if (!atomic_dec_and_test(&ibr->pending))
535 return;
536
537 if (atomic_read(&ibr->ib_bio_err_cnt))
538 status = SAM_STAT_CHECK_CONDITION;
539 else
540 status = SAM_STAT_GOOD;
541
542 target_complete_cmd(cmd, status);
543 kfree(ibr);
544 }
545
546 static void iblock_bio_destructor(struct bio *bio)
547 {
548 struct se_cmd *cmd = bio->bi_private;
549 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
550
551 bio_free(bio, ib_dev->ibd_bio_set);
552 }
553
554 static struct bio *
555 iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num)
556 {
557 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
558 struct bio *bio;
559
560 /*
561 * Only allocate as many vector entries as the bio code allows us to,
562 * we'll loop later on until we have handled the whole request.
563 */
564 if (sg_num > BIO_MAX_PAGES)
565 sg_num = BIO_MAX_PAGES;
566
567 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
568 if (!bio) {
569 pr_err("Unable to allocate memory for bio\n");
570 return NULL;
571 }
572
573 bio->bi_bdev = ib_dev->ibd_bd;
574 bio->bi_private = cmd;
575 bio->bi_destructor = iblock_bio_destructor;
576 bio->bi_end_io = &iblock_bio_done;
577 bio->bi_sector = lba;
578 return bio;
579 }
580
581 static void iblock_submit_bios(struct bio_list *list, int rw)
582 {
583 struct blk_plug plug;
584 struct bio *bio;
585
586 blk_start_plug(&plug);
587 while ((bio = bio_list_pop(list)))
588 submit_bio(rw, bio);
589 blk_finish_plug(&plug);
590 }
591
592 static int iblock_execute_rw(struct se_cmd *cmd)
593 {
594 struct scatterlist *sgl = cmd->t_data_sg;
595 u32 sgl_nents = cmd->t_data_nents;
596 enum dma_data_direction data_direction = cmd->data_direction;
597 struct se_device *dev = cmd->se_dev;
598 struct iblock_req *ibr;
599 struct bio *bio;
600 struct bio_list list;
601 struct scatterlist *sg;
602 u32 sg_num = sgl_nents;
603 sector_t block_lba;
604 unsigned bio_cnt;
605 int rw;
606 int i;
607
608 if (data_direction == DMA_TO_DEVICE) {
609 /*
610 * Force data to disk if we pretend to not have a volatile
611 * write cache, or the initiator set the Force Unit Access bit.
612 */
613 if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache == 0 ||
614 (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
615 (cmd->se_cmd_flags & SCF_FUA)))
616 rw = WRITE_FUA;
617 else
618 rw = WRITE;
619 } else {
620 rw = READ;
621 }
622
623 /*
624 * Convert the blocksize advertised to the initiator to the 512 byte
625 * units unconditionally used by the Linux block layer.
626 */
627 if (dev->se_sub_dev->se_dev_attrib.block_size == 4096)
628 block_lba = (cmd->t_task_lba << 3);
629 else if (dev->se_sub_dev->se_dev_attrib.block_size == 2048)
630 block_lba = (cmd->t_task_lba << 2);
631 else if (dev->se_sub_dev->se_dev_attrib.block_size == 1024)
632 block_lba = (cmd->t_task_lba << 1);
633 else if (dev->se_sub_dev->se_dev_attrib.block_size == 512)
634 block_lba = cmd->t_task_lba;
635 else {
636 pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
637 " %u\n", dev->se_sub_dev->se_dev_attrib.block_size);
638 cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
639 return -ENOSYS;
640 }
641
642 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
643 if (!ibr)
644 goto fail;
645 cmd->priv = ibr;
646
647 bio = iblock_get_bio(cmd, block_lba, sgl_nents);
648 if (!bio)
649 goto fail_free_ibr;
650
651 bio_list_init(&list);
652 bio_list_add(&list, bio);
653
654 atomic_set(&ibr->pending, 2);
655 bio_cnt = 1;
656
657 for_each_sg(sgl, sg, sgl_nents, i) {
658 /*
659 * XXX: if the length the device accepts is shorter than the
660 * length of the S/G list entry this will cause and
661 * endless loop. Better hope no driver uses huge pages.
662 */
663 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
664 != sg->length) {
665 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
666 iblock_submit_bios(&list, rw);
667 bio_cnt = 0;
668 }
669
670 bio = iblock_get_bio(cmd, block_lba, sg_num);
671 if (!bio)
672 goto fail_put_bios;
673
674 atomic_inc(&ibr->pending);
675 bio_list_add(&list, bio);
676 bio_cnt++;
677 }
678
679 /* Always in 512 byte units for Linux/Block */
680 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
681 sg_num--;
682 }
683
684 iblock_submit_bios(&list, rw);
685 iblock_complete_cmd(cmd);
686 return 0;
687
688 fail_put_bios:
689 while ((bio = bio_list_pop(&list)))
690 bio_put(bio);
691 fail_free_ibr:
692 kfree(ibr);
693 cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
694 fail:
695 return -ENOMEM;
696 }
697
698 static u32 iblock_get_device_rev(struct se_device *dev)
699 {
700 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
701 }
702
703 static u32 iblock_get_device_type(struct se_device *dev)
704 {
705 return TYPE_DISK;
706 }
707
708 static sector_t iblock_get_blocks(struct se_device *dev)
709 {
710 struct iblock_dev *ibd = dev->dev_ptr;
711 struct block_device *bd = ibd->ibd_bd;
712 struct request_queue *q = bdev_get_queue(bd);
713
714 return iblock_emulate_read_cap_with_block_size(dev, bd, q);
715 }
716
717 static void iblock_bio_done(struct bio *bio, int err)
718 {
719 struct se_cmd *cmd = bio->bi_private;
720 struct iblock_req *ibr = cmd->priv;
721
722 /*
723 * Set -EIO if !BIO_UPTODATE and the passed is still err=0
724 */
725 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
726 err = -EIO;
727
728 if (err != 0) {
729 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
730 " err: %d\n", bio, err);
731 /*
732 * Bump the ib_bio_err_cnt and release bio.
733 */
734 atomic_inc(&ibr->ib_bio_err_cnt);
735 smp_mb__after_atomic_inc();
736 }
737
738 bio_put(bio);
739
740 iblock_complete_cmd(cmd);
741 }
742
743 static struct spc_ops iblock_spc_ops = {
744 .execute_rw = iblock_execute_rw,
745 .execute_sync_cache = iblock_execute_sync_cache,
746 .execute_write_same = iblock_execute_write_same,
747 .execute_unmap = iblock_execute_unmap,
748 };
749
750 static int iblock_parse_cdb(struct se_cmd *cmd)
751 {
752 return sbc_parse_cdb(cmd, &iblock_spc_ops);
753 }
754
755 static struct se_subsystem_api iblock_template = {
756 .name = "iblock",
757 .owner = THIS_MODULE,
758 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
759 .write_cache_emulated = 1,
760 .fua_write_emulated = 1,
761 .attach_hba = iblock_attach_hba,
762 .detach_hba = iblock_detach_hba,
763 .allocate_virtdevice = iblock_allocate_virtdevice,
764 .create_virtdevice = iblock_create_virtdevice,
765 .free_device = iblock_free_device,
766 .parse_cdb = iblock_parse_cdb,
767 .check_configfs_dev_params = iblock_check_configfs_dev_params,
768 .set_configfs_dev_params = iblock_set_configfs_dev_params,
769 .show_configfs_dev_params = iblock_show_configfs_dev_params,
770 .get_device_rev = iblock_get_device_rev,
771 .get_device_type = iblock_get_device_type,
772 .get_blocks = iblock_get_blocks,
773 };
774
775 static int __init iblock_module_init(void)
776 {
777 return transport_subsystem_register(&iblock_template);
778 }
779
780 static void iblock_module_exit(void)
781 {
782 transport_subsystem_release(&iblock_template);
783 }
784
785 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
786 MODULE_AUTHOR("nab@Linux-iSCSI.org");
787 MODULE_LICENSE("GPL");
788
789 module_init(iblock_module_init);
790 module_exit(iblock_module_exit);
Linux kernel - Deliverables
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