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mfd, TWL4030: TWL4030 need select REGMAP_I2C
[linux-2.6/libata-dev.git] / drivers / target / target_core_iblock.c
blobb526d23dcd4f178be3fd06b4fdcc273a0ba78a4f
1 /*******************************************************************************
2 * Filename: target_core_iblock.c
3 *
4 * This file contains the Storage Engine <-> Linux BlockIO transport
5 * specific functions.
6 *
7 * (c) Copyright 2003-2012 RisingTide Systems LLC.
8 *
9 * Nicholas A. Bellinger <nab@kernel.org>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 *
25 ******************************************************************************/
26
27 #include <linux/string.h>
28 #include <linux/parser.h>
29 #include <linux/timer.h>
30 #include <linux/fs.h>
31 #include <linux/blkdev.h>
32 #include <linux/slab.h>
33 #include <linux/spinlock.h>
34 #include <linux/bio.h>
35 #include <linux/genhd.h>
36 #include <linux/file.h>
37 #include <linux/module.h>
38 #include <scsi/scsi.h>
39 #include <scsi/scsi_host.h>
40 #include <asm/unaligned.h>
41
42 #include <target/target_core_base.h>
43 #include <target/target_core_backend.h>
44
45 #include "target_core_iblock.h"
46
47 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */
48 #define IBLOCK_BIO_POOL_SIZE 128
49
50 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev)
51 {
52 return container_of(dev, struct iblock_dev, dev);
53 }
54
55
56 static struct se_subsystem_api iblock_template;
57
58 /* iblock_attach_hba(): (Part of se_subsystem_api_t template)
59 *
60 *
61 */
62 static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
63 {
64 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
65 " Generic Target Core Stack %s\n", hba->hba_id,
66 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
67 return 0;
68 }
69
70 static void iblock_detach_hba(struct se_hba *hba)
71 {
72 }
73
74 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name)
75 {
76 struct iblock_dev *ib_dev = NULL;
77
78 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
79 if (!ib_dev) {
80 pr_err("Unable to allocate struct iblock_dev\n");
81 return NULL;
82 }
83
84 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
85
86 return &ib_dev->dev;
87 }
88
89 static int iblock_configure_device(struct se_device *dev)
90 {
91 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
92 struct request_queue *q;
93 struct block_device *bd = NULL;
94 fmode_t mode;
95 int ret = -ENOMEM;
96
97 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) {
98 pr_err("Missing udev_path= parameters for IBLOCK\n");
99 return -EINVAL;
100 }
101
102 ib_dev->ibd_bio_set = bioset_create(IBLOCK_BIO_POOL_SIZE, 0);
103 if (!ib_dev->ibd_bio_set) {
104 pr_err("IBLOCK: Unable to create bioset\n");
105 goto out;
106 }
107
108 pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
109 ib_dev->ibd_udev_path);
110
111 mode = FMODE_READ|FMODE_EXCL;
112 if (!ib_dev->ibd_readonly)
113 mode |= FMODE_WRITE;
114
115 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev);
116 if (IS_ERR(bd)) {
117 ret = PTR_ERR(bd);
118 goto out_free_bioset;
119 }
120 ib_dev->ibd_bd = bd;
121
122 q = bdev_get_queue(bd);
123
124 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
125 dev->dev_attrib.hw_max_sectors = UINT_MAX;
126 dev->dev_attrib.hw_queue_depth = q->nr_requests;
127
128 /*
129 * Check if the underlying struct block_device request_queue supports
130 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
131 * in ATA and we need to set TPE=1
132 */
133 if (blk_queue_discard(q)) {
134 dev->dev_attrib.max_unmap_lba_count =
135 q->limits.max_discard_sectors;
136
137 /*
138 * Currently hardcoded to 1 in Linux/SCSI code..
139 */
140 dev->dev_attrib.max_unmap_block_desc_count = 1;
141 dev->dev_attrib.unmap_granularity =
142 q->limits.discard_granularity >> 9;
143 dev->dev_attrib.unmap_granularity_alignment =
144 q->limits.discard_alignment;
145
146 pr_debug("IBLOCK: BLOCK Discard support available,"
147 " disabled by default\n");
148 }
149 /*
150 * Enable write same emulation for IBLOCK and use 0xFFFF as
151 * the smaller WRITE_SAME(10) only has a two-byte block count.
152 */
153 dev->dev_attrib.max_write_same_len = 0xFFFF;
154
155 if (blk_queue_nonrot(q))
156 dev->dev_attrib.is_nonrot = 1;
157 return 0;
158
159 out_free_bioset:
160 bioset_free(ib_dev->ibd_bio_set);
161 ib_dev->ibd_bio_set = NULL;
162 out:
163 return ret;
164 }
165
166 static void iblock_free_device(struct se_device *dev)
167 {
168 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
169
170 if (ib_dev->ibd_bd != NULL)
171 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
172 if (ib_dev->ibd_bio_set != NULL)
173 bioset_free(ib_dev->ibd_bio_set);
174 kfree(ib_dev);
175 }
176
177 static unsigned long long iblock_emulate_read_cap_with_block_size(
178 struct se_device *dev,
179 struct block_device *bd,
180 struct request_queue *q)
181 {
182 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
183 bdev_logical_block_size(bd)) - 1);
184 u32 block_size = bdev_logical_block_size(bd);
185
186 if (block_size == dev->dev_attrib.block_size)
187 return blocks_long;
188
189 switch (block_size) {
190 case 4096:
191 switch (dev->dev_attrib.block_size) {
192 case 2048:
193 blocks_long <<= 1;
194 break;
195 case 1024:
196 blocks_long <<= 2;
197 break;
198 case 512:
199 blocks_long <<= 3;
200 default:
201 break;
202 }
203 break;
204 case 2048:
205 switch (dev->dev_attrib.block_size) {
206 case 4096:
207 blocks_long >>= 1;
208 break;
209 case 1024:
210 blocks_long <<= 1;
211 break;
212 case 512:
213 blocks_long <<= 2;
214 break;
215 default:
216 break;
217 }
218 break;
219 case 1024:
220 switch (dev->dev_attrib.block_size) {
221 case 4096:
222 blocks_long >>= 2;
223 break;
224 case 2048:
225 blocks_long >>= 1;
226 break;
227 case 512:
228 blocks_long <<= 1;
229 break;
230 default:
231 break;
232 }
233 break;
234 case 512:
235 switch (dev->dev_attrib.block_size) {
236 case 4096:
237 blocks_long >>= 3;
238 break;
239 case 2048:
240 blocks_long >>= 2;
241 break;
242 case 1024:
243 blocks_long >>= 1;
244 break;
245 default:
246 break;
247 }
248 break;
249 default:
250 break;
251 }
252
253 return blocks_long;
254 }
255
256 static void iblock_complete_cmd(struct se_cmd *cmd)
257 {
258 struct iblock_req *ibr = cmd->priv;
259 u8 status;
260
261 if (!atomic_dec_and_test(&ibr->pending))
262 return;
263
264 if (atomic_read(&ibr->ib_bio_err_cnt))
265 status = SAM_STAT_CHECK_CONDITION;
266 else
267 status = SAM_STAT_GOOD;
268
269 target_complete_cmd(cmd, status);
270 kfree(ibr);
271 }
272
273 static void iblock_bio_done(struct bio *bio, int err)
274 {
275 struct se_cmd *cmd = bio->bi_private;
276 struct iblock_req *ibr = cmd->priv;
277
278 /*
279 * Set -EIO if !BIO_UPTODATE and the passed is still err=0
280 */
281 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
282 err = -EIO;
283
284 if (err != 0) {
285 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
286 " err: %d\n", bio, err);
287 /*
288 * Bump the ib_bio_err_cnt and release bio.
289 */
290 atomic_inc(&ibr->ib_bio_err_cnt);
291 smp_mb__after_atomic_inc();
292 }
293
294 bio_put(bio);
295
296 iblock_complete_cmd(cmd);
297 }
298
299 static struct bio *
300 iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num)
301 {
302 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
303 struct bio *bio;
304
305 /*
306 * Only allocate as many vector entries as the bio code allows us to,
307 * we'll loop later on until we have handled the whole request.
308 */
309 if (sg_num > BIO_MAX_PAGES)
310 sg_num = BIO_MAX_PAGES;
311
312 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
313 if (!bio) {
314 pr_err("Unable to allocate memory for bio\n");
315 return NULL;
316 }
317
318 bio->bi_bdev = ib_dev->ibd_bd;
319 bio->bi_private = cmd;
320 bio->bi_end_io = &iblock_bio_done;
321 bio->bi_sector = lba;
322
323 return bio;
324 }
325
326 static void iblock_submit_bios(struct bio_list *list, int rw)
327 {
328 struct blk_plug plug;
329 struct bio *bio;
330
331 blk_start_plug(&plug);
332 while ((bio = bio_list_pop(list)))
333 submit_bio(rw, bio);
334 blk_finish_plug(&plug);
335 }
336
337 static void iblock_end_io_flush(struct bio *bio, int err)
338 {
339 struct se_cmd *cmd = bio->bi_private;
340
341 if (err)
342 pr_err("IBLOCK: cache flush failed: %d\n", err);
343
344 if (cmd) {
345 if (err)
346 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
347 else
348 target_complete_cmd(cmd, SAM_STAT_GOOD);
349 }
350
351 bio_put(bio);
352 }
353
354 /*
355 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
356 * always flush the whole cache.
357 */
358 static sense_reason_t
359 iblock_execute_sync_cache(struct se_cmd *cmd)
360 {
361 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
362 int immed = (cmd->t_task_cdb[1] & 0x2);
363 struct bio *bio;
364
365 /*
366 * If the Immediate bit is set, queue up the GOOD response
367 * for this SYNCHRONIZE_CACHE op.
368 */
369 if (immed)
370 target_complete_cmd(cmd, SAM_STAT_GOOD);
371
372 bio = bio_alloc(GFP_KERNEL, 0);
373 bio->bi_end_io = iblock_end_io_flush;
374 bio->bi_bdev = ib_dev->ibd_bd;
375 if (!immed)
376 bio->bi_private = cmd;
377 submit_bio(WRITE_FLUSH, bio);
378 return 0;
379 }
380
381 static sense_reason_t
382 iblock_execute_unmap(struct se_cmd *cmd)
383 {
384 struct se_device *dev = cmd->se_dev;
385 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
386 unsigned char *buf, *ptr = NULL;
387 sector_t lba;
388 int size;
389 u32 range;
390 sense_reason_t ret = 0;
391 int dl, bd_dl, err;
392
393 if (cmd->data_length < 8) {
394 pr_warn("UNMAP parameter list length %u too small\n",
395 cmd->data_length);
396 return TCM_INVALID_PARAMETER_LIST;
397 }
398
399 buf = transport_kmap_data_sg(cmd);
400 if (!buf)
401 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
402
403 dl = get_unaligned_be16(&buf[0]);
404 bd_dl = get_unaligned_be16(&buf[2]);
405
406 size = cmd->data_length - 8;
407 if (bd_dl > size)
408 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
409 cmd->data_length, bd_dl);
410 else
411 size = bd_dl;
412
413 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
414 ret = TCM_INVALID_PARAMETER_LIST;
415 goto err;
416 }
417
418 /* First UNMAP block descriptor starts at 8 byte offset */
419 ptr = &buf[8];
420 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
421 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
422
423 while (size >= 16) {
424 lba = get_unaligned_be64(&ptr[0]);
425 range = get_unaligned_be32(&ptr[8]);
426 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
427 (unsigned long long)lba, range);
428
429 if (range > dev->dev_attrib.max_unmap_lba_count) {
430 ret = TCM_INVALID_PARAMETER_LIST;
431 goto err;
432 }
433
434 if (lba + range > dev->transport->get_blocks(dev) + 1) {
435 ret = TCM_ADDRESS_OUT_OF_RANGE;
436 goto err;
437 }
438
439 err = blkdev_issue_discard(ib_dev->ibd_bd, lba, range,
440 GFP_KERNEL, 0);
441 if (err < 0) {
442 pr_err("blkdev_issue_discard() failed: %d\n",
443 err);
444 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
445 goto err;
446 }
447
448 ptr += 16;
449 size -= 16;
450 }
451
452 err:
453 transport_kunmap_data_sg(cmd);
454 if (!ret)
455 target_complete_cmd(cmd, GOOD);
456 return ret;
457 }
458
459 static sense_reason_t
460 iblock_execute_write_same_unmap(struct se_cmd *cmd)
461 {
462 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
463 int rc;
464
465 rc = blkdev_issue_discard(ib_dev->ibd_bd, cmd->t_task_lba,
466 spc_get_write_same_sectors(cmd), GFP_KERNEL, 0);
467 if (rc < 0) {
468 pr_warn("blkdev_issue_discard() failed: %d\n", rc);
469 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
470 }
471
472 target_complete_cmd(cmd, GOOD);
473 return 0;
474 }
475
476 static sense_reason_t
477 iblock_execute_write_same(struct se_cmd *cmd)
478 {
479 struct iblock_req *ibr;
480 struct scatterlist *sg;
481 struct bio *bio;
482 struct bio_list list;
483 sector_t block_lba = cmd->t_task_lba;
484 sector_t sectors = spc_get_write_same_sectors(cmd);
485
486 sg = &cmd->t_data_sg[0];
487
488 if (cmd->t_data_nents > 1 ||
489 sg->length != cmd->se_dev->dev_attrib.block_size) {
490 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
491 " block_size: %u\n", cmd->t_data_nents, sg->length,
492 cmd->se_dev->dev_attrib.block_size);
493 return TCM_INVALID_CDB_FIELD;
494 }
495
496 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
497 if (!ibr)
498 goto fail;
499 cmd->priv = ibr;
500
501 bio = iblock_get_bio(cmd, block_lba, 1);
502 if (!bio)
503 goto fail_free_ibr;
504
505 bio_list_init(&list);
506 bio_list_add(&list, bio);
507
508 atomic_set(&ibr->pending, 1);
509
510 while (sectors) {
511 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
512 != sg->length) {
513
514 bio = iblock_get_bio(cmd, block_lba, 1);
515 if (!bio)
516 goto fail_put_bios;
517
518 atomic_inc(&ibr->pending);
519 bio_list_add(&list, bio);
520 }
521
522 /* Always in 512 byte units for Linux/Block */
523 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
524 sectors -= 1;
525 }
526
527 iblock_submit_bios(&list, WRITE);
528 return 0;
529
530 fail_put_bios:
531 while ((bio = bio_list_pop(&list)))
532 bio_put(bio);
533 fail_free_ibr:
534 kfree(ibr);
535 fail:
536 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
537 }
538
539 enum {
540 Opt_udev_path, Opt_readonly, Opt_force, Opt_err
541 };
542
543 static match_table_t tokens = {
544 {Opt_udev_path, "udev_path=%s"},
545 {Opt_readonly, "readonly=%d"},
546 {Opt_force, "force=%d"},
547 {Opt_err, NULL}
548 };
549
550 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
551 const char *page, ssize_t count)
552 {
553 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
554 char *orig, *ptr, *arg_p, *opts;
555 substring_t args[MAX_OPT_ARGS];
556 int ret = 0, token;
557 unsigned long tmp_readonly;
558
559 opts = kstrdup(page, GFP_KERNEL);
560 if (!opts)
561 return -ENOMEM;
562
563 orig = opts;
564
565 while ((ptr = strsep(&opts, ",\n")) != NULL) {
566 if (!*ptr)
567 continue;
568
569 token = match_token(ptr, tokens, args);
570 switch (token) {
571 case Opt_udev_path:
572 if (ib_dev->ibd_bd) {
573 pr_err("Unable to set udev_path= while"
574 " ib_dev->ibd_bd exists\n");
575 ret = -EEXIST;
576 goto out;
577 }
578 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0],
579 SE_UDEV_PATH_LEN) == 0) {
580 ret = -EINVAL;
581 break;
582 }
583 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
584 ib_dev->ibd_udev_path);
585 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
586 break;
587 case Opt_readonly:
588 arg_p = match_strdup(&args[0]);
589 if (!arg_p) {
590 ret = -ENOMEM;
591 break;
592 }
593 ret = strict_strtoul(arg_p, 0, &tmp_readonly);
594 kfree(arg_p);
595 if (ret < 0) {
596 pr_err("strict_strtoul() failed for"
597 " readonly=\n");
598 goto out;
599 }
600 ib_dev->ibd_readonly = tmp_readonly;
601 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
602 break;
603 case Opt_force:
604 break;
605 default:
606 break;
607 }
608 }
609
610 out:
611 kfree(orig);
612 return (!ret) ? count : ret;
613 }
614
615 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
616 {
617 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
618 struct block_device *bd = ib_dev->ibd_bd;
619 char buf[BDEVNAME_SIZE];
620 ssize_t bl = 0;
621
622 if (bd)
623 bl += sprintf(b + bl, "iBlock device: %s",
624 bdevname(bd, buf));
625 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
626 bl += sprintf(b + bl, " UDEV PATH: %s",
627 ib_dev->ibd_udev_path);
628 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly);
629
630 bl += sprintf(b + bl, " ");
631 if (bd) {
632 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
633 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
634 "" : (bd->bd_holder == ib_dev) ?
635 "CLAIMED: IBLOCK" : "CLAIMED: OS");
636 } else {
637 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
638 }
639
640 return bl;
641 }
642
643 static sense_reason_t
644 iblock_execute_rw(struct se_cmd *cmd)
645 {
646 struct scatterlist *sgl = cmd->t_data_sg;
647 u32 sgl_nents = cmd->t_data_nents;
648 enum dma_data_direction data_direction = cmd->data_direction;
649 struct se_device *dev = cmd->se_dev;
650 struct iblock_req *ibr;
651 struct bio *bio;
652 struct bio_list list;
653 struct scatterlist *sg;
654 u32 sg_num = sgl_nents;
655 sector_t block_lba;
656 unsigned bio_cnt;
657 int rw;
658 int i;
659
660 if (data_direction == DMA_TO_DEVICE) {
661 /*
662 * Force data to disk if we pretend to not have a volatile
663 * write cache, or the initiator set the Force Unit Access bit.
664 */
665 if (dev->dev_attrib.emulate_write_cache == 0 ||
666 (dev->dev_attrib.emulate_fua_write > 0 &&
667 (cmd->se_cmd_flags & SCF_FUA)))
668 rw = WRITE_FUA;
669 else
670 rw = WRITE;
671 } else {
672 rw = READ;
673 }
674
675 /*
676 * Convert the blocksize advertised to the initiator to the 512 byte
677 * units unconditionally used by the Linux block layer.
678 */
679 if (dev->dev_attrib.block_size == 4096)
680 block_lba = (cmd->t_task_lba << 3);
681 else if (dev->dev_attrib.block_size == 2048)
682 block_lba = (cmd->t_task_lba << 2);
683 else if (dev->dev_attrib.block_size == 1024)
684 block_lba = (cmd->t_task_lba << 1);
685 else if (dev->dev_attrib.block_size == 512)
686 block_lba = cmd->t_task_lba;
687 else {
688 pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
689 " %u\n", dev->dev_attrib.block_size);
690 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
691 }
692
693 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
694 if (!ibr)
695 goto fail;
696 cmd->priv = ibr;
697
698 if (!sgl_nents) {
699 atomic_set(&ibr->pending, 1);
700 iblock_complete_cmd(cmd);
701 return 0;
702 }
703
704 bio = iblock_get_bio(cmd, block_lba, sgl_nents);
705 if (!bio)
706 goto fail_free_ibr;
707
708 bio_list_init(&list);
709 bio_list_add(&list, bio);
710
711 atomic_set(&ibr->pending, 2);
712 bio_cnt = 1;
713
714 for_each_sg(sgl, sg, sgl_nents, i) {
715 /*
716 * XXX: if the length the device accepts is shorter than the
717 * length of the S/G list entry this will cause and
718 * endless loop. Better hope no driver uses huge pages.
719 */
720 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
721 != sg->length) {
722 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
723 iblock_submit_bios(&list, rw);
724 bio_cnt = 0;
725 }
726
727 bio = iblock_get_bio(cmd, block_lba, sg_num);
728 if (!bio)
729 goto fail_put_bios;
730
731 atomic_inc(&ibr->pending);
732 bio_list_add(&list, bio);
733 bio_cnt++;
734 }
735
736 /* Always in 512 byte units for Linux/Block */
737 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
738 sg_num--;
739 }
740
741 iblock_submit_bios(&list, rw);
742 iblock_complete_cmd(cmd);
743 return 0;
744
745 fail_put_bios:
746 while ((bio = bio_list_pop(&list)))
747 bio_put(bio);
748 fail_free_ibr:
749 kfree(ibr);
750 fail:
751 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
752 }
753
754 static sector_t iblock_get_blocks(struct se_device *dev)
755 {
756 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
757 struct block_device *bd = ib_dev->ibd_bd;
758 struct request_queue *q = bdev_get_queue(bd);
759
760 return iblock_emulate_read_cap_with_block_size(dev, bd, q);
761 }
762
763 static struct sbc_ops iblock_sbc_ops = {
764 .execute_rw = iblock_execute_rw,
765 .execute_sync_cache = iblock_execute_sync_cache,
766 .execute_write_same = iblock_execute_write_same,
767 .execute_write_same_unmap = iblock_execute_write_same_unmap,
768 .execute_unmap = iblock_execute_unmap,
769 };
770
771 static sense_reason_t
772 iblock_parse_cdb(struct se_cmd *cmd)
773 {
774 return sbc_parse_cdb(cmd, &iblock_sbc_ops);
775 }
776
777 static struct se_subsystem_api iblock_template = {
778 .name = "iblock",
779 .inquiry_prod = "IBLOCK",
780 .inquiry_rev = IBLOCK_VERSION,
781 .owner = THIS_MODULE,
782 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
783 .attach_hba = iblock_attach_hba,
784 .detach_hba = iblock_detach_hba,
785 .alloc_device = iblock_alloc_device,
786 .configure_device = iblock_configure_device,
787 .free_device = iblock_free_device,
788 .parse_cdb = iblock_parse_cdb,
789 .set_configfs_dev_params = iblock_set_configfs_dev_params,
790 .show_configfs_dev_params = iblock_show_configfs_dev_params,
791 .get_device_type = sbc_get_device_type,
792 .get_blocks = iblock_get_blocks,
793 };
794
795 static int __init iblock_module_init(void)
796 {
797 return transport_subsystem_register(&iblock_template);
798 }
799
800 static void iblock_module_exit(void)
801 {
802 transport_subsystem_release(&iblock_template);
803 }
804
805 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
806 MODULE_AUTHOR("nab@Linux-iSCSI.org");
807 MODULE_LICENSE("GPL");
808
809 module_init(iblock_module_init);
810 module_exit(iblock_module_exit);
Linux 2.6 libata-dev (mirror)