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target: Core cleanups from AGrover (round 1)
[GitHub/mt8127/android_kernel_alcatel_ttab.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/version.h>
31 #include <linux/string.h>
32 #include <linux/parser.h>
33 #include <linux/timer.h>
34 #include <linux/fs.h>
35 #include <linux/blkdev.h>
36 #include <linux/slab.h>
37 #include <linux/spinlock.h>
38 #include <linux/bio.h>
39 #include <linux/genhd.h>
40 #include <linux/file.h>
41 #include <scsi/scsi.h>
42 #include <scsi/scsi_host.h>
43
44 #include <target/target_core_base.h>
45 #include <target/target_core_device.h>
46 #include <target/target_core_transport.h>
47
48 #include "target_core_iblock.h"
49
50 #if 0
51 #define DEBUG_IBLOCK(x...) printk(x)
52 #else
53 #define DEBUG_IBLOCK(x...)
54 #endif
55
56 static struct se_subsystem_api iblock_template;
57
58 static void iblock_bio_done(struct bio *, int);
59
60 /* iblock_attach_hba(): (Part of se_subsystem_api_t template)
61 *
62 *
63 */
64 static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
65 {
66 struct iblock_hba *ib_host;
67
68 ib_host = kzalloc(sizeof(struct iblock_hba), GFP_KERNEL);
69 if (!(ib_host)) {
70 printk(KERN_ERR "Unable to allocate memory for"
71 " struct iblock_hba\n");
72 return -ENOMEM;
73 }
74
75 ib_host->iblock_host_id = host_id;
76
77 hba->hba_ptr = (void *) ib_host;
78
79 printk(KERN_INFO "CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
80 " Generic Target Core Stack %s\n", hba->hba_id,
81 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
82
83 printk(KERN_INFO "CORE_HBA[%d] - Attached iBlock HBA: %u to Generic\n",
84 hba->hba_id, ib_host->iblock_host_id);
85
86 return 0;
87 }
88
89 static void iblock_detach_hba(struct se_hba *hba)
90 {
91 struct iblock_hba *ib_host = hba->hba_ptr;
92
93 printk(KERN_INFO "CORE_HBA[%d] - Detached iBlock HBA: %u from Generic"
94 " Target Core\n", hba->hba_id, ib_host->iblock_host_id);
95
96 kfree(ib_host);
97 hba->hba_ptr = NULL;
98 }
99
100 static void *iblock_allocate_virtdevice(struct se_hba *hba, const char *name)
101 {
102 struct iblock_dev *ib_dev = NULL;
103 struct iblock_hba *ib_host = hba->hba_ptr;
104
105 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
106 if (!(ib_dev)) {
107 printk(KERN_ERR "Unable to allocate struct iblock_dev\n");
108 return NULL;
109 }
110 ib_dev->ibd_host = ib_host;
111
112 printk(KERN_INFO "IBLOCK: Allocated ib_dev for %s\n", name);
113
114 return ib_dev;
115 }
116
117 static struct se_device *iblock_create_virtdevice(
118 struct se_hba *hba,
119 struct se_subsystem_dev *se_dev,
120 void *p)
121 {
122 struct iblock_dev *ib_dev = p;
123 struct se_device *dev;
124 struct se_dev_limits dev_limits;
125 struct block_device *bd = NULL;
126 struct request_queue *q;
127 struct queue_limits *limits;
128 u32 dev_flags = 0;
129 int ret = -EINVAL;
130
131 if (!(ib_dev)) {
132 printk(KERN_ERR "Unable to locate struct iblock_dev parameter\n");
133 return ERR_PTR(ret);
134 }
135 memset(&dev_limits, 0, sizeof(struct se_dev_limits));
136 /*
137 * These settings need to be made tunable..
138 */
139 ib_dev->ibd_bio_set = bioset_create(32, 64);
140 if (!(ib_dev->ibd_bio_set)) {
141 printk(KERN_ERR "IBLOCK: Unable to create bioset()\n");
142 return ERR_PTR(-ENOMEM);
143 }
144 printk(KERN_INFO "IBLOCK: Created bio_set()\n");
145 /*
146 * iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path
147 * must already have been set in order for echo 1 > $HBA/$DEV/enable to run.
148 */
149 printk(KERN_INFO "IBLOCK: Claiming struct block_device: %s\n",
150 ib_dev->ibd_udev_path);
151
152 bd = blkdev_get_by_path(ib_dev->ibd_udev_path,
153 FMODE_WRITE|FMODE_READ|FMODE_EXCL, ib_dev);
154 if (IS_ERR(bd)) {
155 ret = PTR_ERR(bd);
156 goto failed;
157 }
158 /*
159 * Setup the local scope queue_limits from struct request_queue->limits
160 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
161 */
162 q = bdev_get_queue(bd);
163 limits = &dev_limits.limits;
164 limits->logical_block_size = bdev_logical_block_size(bd);
165 limits->max_hw_sectors = queue_max_hw_sectors(q);
166 limits->max_sectors = queue_max_sectors(q);
167 dev_limits.hw_queue_depth = IBLOCK_MAX_DEVICE_QUEUE_DEPTH;
168 dev_limits.queue_depth = IBLOCK_DEVICE_QUEUE_DEPTH;
169
170 ib_dev->ibd_major = MAJOR(bd->bd_dev);
171 ib_dev->ibd_minor = MINOR(bd->bd_dev);
172 ib_dev->ibd_bd = bd;
173
174 dev = transport_add_device_to_core_hba(hba,
175 &iblock_template, se_dev, dev_flags, (void *)ib_dev,
176 &dev_limits, "IBLOCK", IBLOCK_VERSION);
177 if (!(dev))
178 goto failed;
179
180 ib_dev->ibd_depth = dev->queue_depth;
181
182 /*
183 * Check if the underlying struct block_device request_queue supports
184 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
185 * in ATA and we need to set TPE=1
186 */
187 if (blk_queue_discard(q)) {
188 dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count =
189 q->limits.max_discard_sectors;
190 /*
191 * Currently hardcoded to 1 in Linux/SCSI code..
192 */
193 dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count = 1;
194 dev->se_sub_dev->se_dev_attrib.unmap_granularity =
195 q->limits.discard_granularity;
196 dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment =
197 q->limits.discard_alignment;
198
199 printk(KERN_INFO "IBLOCK: BLOCK Discard support available,"
200 " disabled by default\n");
201 }
202
203 return dev;
204
205 failed:
206 if (ib_dev->ibd_bio_set) {
207 bioset_free(ib_dev->ibd_bio_set);
208 ib_dev->ibd_bio_set = NULL;
209 }
210 ib_dev->ibd_bd = NULL;
211 ib_dev->ibd_major = 0;
212 ib_dev->ibd_minor = 0;
213 return ERR_PTR(ret);
214 }
215
216 static void iblock_free_device(void *p)
217 {
218 struct iblock_dev *ib_dev = p;
219
220 if (ib_dev->ibd_bd != NULL)
221 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
222 if (ib_dev->ibd_bio_set != NULL)
223 bioset_free(ib_dev->ibd_bio_set);
224 kfree(ib_dev);
225 }
226
227 static inline struct iblock_req *IBLOCK_REQ(struct se_task *task)
228 {
229 return container_of(task, struct iblock_req, ib_task);
230 }
231
232 static struct se_task *
233 iblock_alloc_task(struct se_cmd *cmd)
234 {
235 struct iblock_req *ib_req;
236
237 ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
238 if (!(ib_req)) {
239 printk(KERN_ERR "Unable to allocate memory for struct iblock_req\n");
240 return NULL;
241 }
242
243 ib_req->ib_dev = cmd->se_lun->lun_se_dev->dev_ptr;
244 atomic_set(&ib_req->ib_bio_cnt, 0);
245 return &ib_req->ib_task;
246 }
247
248 static unsigned long long iblock_emulate_read_cap_with_block_size(
249 struct se_device *dev,
250 struct block_device *bd,
251 struct request_queue *q)
252 {
253 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
254 bdev_logical_block_size(bd)) - 1);
255 u32 block_size = bdev_logical_block_size(bd);
256
257 if (block_size == dev->se_sub_dev->se_dev_attrib.block_size)
258 return blocks_long;
259
260 switch (block_size) {
261 case 4096:
262 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
263 case 2048:
264 blocks_long <<= 1;
265 break;
266 case 1024:
267 blocks_long <<= 2;
268 break;
269 case 512:
270 blocks_long <<= 3;
271 default:
272 break;
273 }
274 break;
275 case 2048:
276 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
277 case 4096:
278 blocks_long >>= 1;
279 break;
280 case 1024:
281 blocks_long <<= 1;
282 break;
283 case 512:
284 blocks_long <<= 2;
285 break;
286 default:
287 break;
288 }
289 break;
290 case 1024:
291 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
292 case 4096:
293 blocks_long >>= 2;
294 break;
295 case 2048:
296 blocks_long >>= 1;
297 break;
298 case 512:
299 blocks_long <<= 1;
300 break;
301 default:
302 break;
303 }
304 break;
305 case 512:
306 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
307 case 4096:
308 blocks_long >>= 3;
309 break;
310 case 2048:
311 blocks_long >>= 2;
312 break;
313 case 1024:
314 blocks_long >>= 1;
315 break;
316 default:
317 break;
318 }
319 break;
320 default:
321 break;
322 }
323
324 return blocks_long;
325 }
326
327 /*
328 * Emulate SYCHRONIZE_CACHE_*
329 */
330 static void iblock_emulate_sync_cache(struct se_task *task)
331 {
332 struct se_cmd *cmd = task->task_se_cmd;
333 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
334 int immed = (cmd->t_task->t_task_cdb[1] & 0x2);
335 sector_t error_sector;
336 int ret;
337
338 /*
339 * If the Immediate bit is set, queue up the GOOD response
340 * for this SYNCHRONIZE_CACHE op
341 */
342 if (immed)
343 transport_complete_sync_cache(cmd, 1);
344
345 /*
346 * blkdev_issue_flush() does not support a specifying a range, so
347 * we have to flush the entire cache.
348 */
349 ret = blkdev_issue_flush(ib_dev->ibd_bd, GFP_KERNEL, &error_sector);
350 if (ret != 0) {
351 printk(KERN_ERR "IBLOCK: block_issue_flush() failed: %d "
352 " error_sector: %llu\n", ret,
353 (unsigned long long)error_sector);
354 }
355
356 if (!immed)
357 transport_complete_sync_cache(cmd, ret == 0);
358 }
359
360 /*
361 * Tell TCM Core that we are capable of WriteCache emulation for
362 * an underlying struct se_device.
363 */
364 static int iblock_emulated_write_cache(struct se_device *dev)
365 {
366 return 1;
367 }
368
369 static int iblock_emulated_dpo(struct se_device *dev)
370 {
371 return 0;
372 }
373
374 /*
375 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs
376 * for TYPE_DISK.
377 */
378 static int iblock_emulated_fua_write(struct se_device *dev)
379 {
380 return 1;
381 }
382
383 static int iblock_emulated_fua_read(struct se_device *dev)
384 {
385 return 0;
386 }
387
388 static int iblock_do_task(struct se_task *task)
389 {
390 struct se_device *dev = task->task_se_cmd->se_dev;
391 struct iblock_req *req = IBLOCK_REQ(task);
392 struct bio *bio = req->ib_bio, *nbio = NULL;
393 struct blk_plug plug;
394 int rw;
395
396 if (task->task_data_direction == DMA_TO_DEVICE) {
397 /*
398 * Force data to disk if we pretend to not have a volatile
399 * write cache, or the initiator set the Force Unit Access bit.
400 */
401 if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache == 0 ||
402 (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
403 task->task_se_cmd->t_task->t_tasks_fua))
404 rw = WRITE_FUA;
405 else
406 rw = WRITE;
407 } else {
408 rw = READ;
409 }
410
411 blk_start_plug(&plug);
412 while (bio) {
413 nbio = bio->bi_next;
414 bio->bi_next = NULL;
415 DEBUG_IBLOCK("Calling submit_bio() task: %p bio: %p"
416 " bio->bi_sector: %llu\n", task, bio, bio->bi_sector);
417
418 submit_bio(rw, bio);
419 bio = nbio;
420 }
421 blk_finish_plug(&plug);
422
423 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
424 }
425
426 static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range)
427 {
428 struct iblock_dev *ibd = dev->dev_ptr;
429 struct block_device *bd = ibd->ibd_bd;
430 int barrier = 0;
431
432 return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier);
433 }
434
435 static void iblock_free_task(struct se_task *task)
436 {
437 struct iblock_req *req = IBLOCK_REQ(task);
438 struct bio *bio, *hbio = req->ib_bio;
439 /*
440 * We only release the bio(s) here if iblock_bio_done() has not called
441 * bio_put() -> iblock_bio_destructor().
442 */
443 while (hbio != NULL) {
444 bio = hbio;
445 hbio = hbio->bi_next;
446 bio->bi_next = NULL;
447 bio_put(bio);
448 }
449
450 kfree(req);
451 }
452
453 enum {
454 Opt_udev_path, Opt_force, Opt_err
455 };
456
457 static match_table_t tokens = {
458 {Opt_udev_path, "udev_path=%s"},
459 {Opt_force, "force=%d"},
460 {Opt_err, NULL}
461 };
462
463 static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
464 struct se_subsystem_dev *se_dev,
465 const char *page, ssize_t count)
466 {
467 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr;
468 char *orig, *ptr, *arg_p, *opts;
469 substring_t args[MAX_OPT_ARGS];
470 int ret = 0, arg, token;
471
472 opts = kstrdup(page, GFP_KERNEL);
473 if (!opts)
474 return -ENOMEM;
475
476 orig = opts;
477
478 while ((ptr = strsep(&opts, ",")) != NULL) {
479 if (!*ptr)
480 continue;
481
482 token = match_token(ptr, tokens, args);
483 switch (token) {
484 case Opt_udev_path:
485 if (ib_dev->ibd_bd) {
486 printk(KERN_ERR "Unable to set udev_path= while"
487 " ib_dev->ibd_bd exists\n");
488 ret = -EEXIST;
489 goto out;
490 }
491 arg_p = match_strdup(&args[0]);
492 if (!arg_p) {
493 ret = -ENOMEM;
494 break;
495 }
496 snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
497 "%s", arg_p);
498 kfree(arg_p);
499 printk(KERN_INFO "IBLOCK: Referencing UDEV path: %s\n",
500 ib_dev->ibd_udev_path);
501 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
502 break;
503 case Opt_force:
504 match_int(args, &arg);
505 ib_dev->ibd_force = arg;
506 printk(KERN_INFO "IBLOCK: Set force=%d\n",
507 ib_dev->ibd_force);
508 break;
509 default:
510 break;
511 }
512 }
513
514 out:
515 kfree(orig);
516 return (!ret) ? count : ret;
517 }
518
519 static ssize_t iblock_check_configfs_dev_params(
520 struct se_hba *hba,
521 struct se_subsystem_dev *se_dev)
522 {
523 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
524
525 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) {
526 printk(KERN_ERR "Missing udev_path= parameters for IBLOCK\n");
527 return -EINVAL;
528 }
529
530 return 0;
531 }
532
533 static ssize_t iblock_show_configfs_dev_params(
534 struct se_hba *hba,
535 struct se_subsystem_dev *se_dev,
536 char *b)
537 {
538 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
539 struct block_device *bd = ibd->ibd_bd;
540 char buf[BDEVNAME_SIZE];
541 ssize_t bl = 0;
542
543 if (bd)
544 bl += sprintf(b + bl, "iBlock device: %s",
545 bdevname(bd, buf));
546 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) {
547 bl += sprintf(b + bl, " UDEV PATH: %s\n",
548 ibd->ibd_udev_path);
549 } else
550 bl += sprintf(b + bl, "\n");
551
552 bl += sprintf(b + bl, " ");
553 if (bd) {
554 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
555 ibd->ibd_major, ibd->ibd_minor, (!bd->bd_contains) ?
556 "" : (bd->bd_holder == (struct iblock_dev *)ibd) ?
557 "CLAIMED: IBLOCK" : "CLAIMED: OS");
558 } else {
559 bl += sprintf(b + bl, "Major: %d Minor: %d\n",
560 ibd->ibd_major, ibd->ibd_minor);
561 }
562
563 return bl;
564 }
565
566 static void iblock_bio_destructor(struct bio *bio)
567 {
568 struct se_task *task = bio->bi_private;
569 struct iblock_dev *ib_dev = task->se_dev->dev_ptr;
570
571 bio_free(bio, ib_dev->ibd_bio_set);
572 }
573
574 static struct bio *iblock_get_bio(
575 struct se_task *task,
576 struct iblock_req *ib_req,
577 struct iblock_dev *ib_dev,
578 int *ret,
579 sector_t lba,
580 u32 sg_num)
581 {
582 struct bio *bio;
583
584 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
585 if (!(bio)) {
586 printk(KERN_ERR "Unable to allocate memory for bio\n");
587 *ret = PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
588 return NULL;
589 }
590
591 DEBUG_IBLOCK("Allocated bio: %p task_sg_num: %u using ibd_bio_set:"
592 " %p\n", bio, task->task_sg_num, ib_dev->ibd_bio_set);
593 DEBUG_IBLOCK("Allocated bio: %p task_size: %u\n", bio, task->task_size);
594
595 bio->bi_bdev = ib_dev->ibd_bd;
596 bio->bi_private = (void *) task;
597 bio->bi_destructor = iblock_bio_destructor;
598 bio->bi_end_io = &iblock_bio_done;
599 bio->bi_sector = lba;
600 atomic_inc(&ib_req->ib_bio_cnt);
601
602 DEBUG_IBLOCK("Set bio->bi_sector: %llu\n", bio->bi_sector);
603 DEBUG_IBLOCK("Set ib_req->ib_bio_cnt: %d\n",
604 atomic_read(&ib_req->ib_bio_cnt));
605 return bio;
606 }
607
608 static int iblock_map_task_SG(struct se_task *task)
609 {
610 struct se_cmd *cmd = task->task_se_cmd;
611 struct se_device *dev = cmd->se_lun->lun_se_dev;
612 struct iblock_dev *ib_dev = task->se_dev->dev_ptr;
613 struct iblock_req *ib_req = IBLOCK_REQ(task);
614 struct bio *bio = NULL, *hbio = NULL, *tbio = NULL;
615 struct scatterlist *sg;
616 int ret = 0;
617 u32 i, sg_num = task->task_sg_num;
618 sector_t block_lba;
619 /*
620 * Do starting conversion up from non 512-byte blocksize with
621 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO.
622 */
623 if (dev->se_sub_dev->se_dev_attrib.block_size == 4096)
624 block_lba = (task->task_lba << 3);
625 else if (dev->se_sub_dev->se_dev_attrib.block_size == 2048)
626 block_lba = (task->task_lba << 2);
627 else if (dev->se_sub_dev->se_dev_attrib.block_size == 1024)
628 block_lba = (task->task_lba << 1);
629 else if (dev->se_sub_dev->se_dev_attrib.block_size == 512)
630 block_lba = task->task_lba;
631 else {
632 printk(KERN_ERR "Unsupported SCSI -> BLOCK LBA conversion:"
633 " %u\n", dev->se_sub_dev->se_dev_attrib.block_size);
634 return PYX_TRANSPORT_LU_COMM_FAILURE;
635 }
636
637 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, block_lba, sg_num);
638 if (!(bio))
639 return ret;
640
641 ib_req->ib_bio = bio;
642 hbio = tbio = bio;
643 /*
644 * Use fs/bio.c:bio_add_pages() to setup the bio_vec maplist
645 * from TCM struct se_mem -> task->task_sg -> struct scatterlist memory.
646 */
647 for_each_sg(task->task_sg, sg, task->task_sg_num, i) {
648 DEBUG_IBLOCK("task: %p bio: %p Calling bio_add_page(): page:"
649 " %p len: %u offset: %u\n", task, bio, sg_page(sg),
650 sg->length, sg->offset);
651 again:
652 ret = bio_add_page(bio, sg_page(sg), sg->length, sg->offset);
653 if (ret != sg->length) {
654
655 DEBUG_IBLOCK("*** Set bio->bi_sector: %llu\n",
656 bio->bi_sector);
657 DEBUG_IBLOCK("** task->task_size: %u\n",
658 task->task_size);
659 DEBUG_IBLOCK("*** bio->bi_max_vecs: %u\n",
660 bio->bi_max_vecs);
661 DEBUG_IBLOCK("*** bio->bi_vcnt: %u\n",
662 bio->bi_vcnt);
663
664 bio = iblock_get_bio(task, ib_req, ib_dev, &ret,
665 block_lba, sg_num);
666 if (!(bio))
667 goto fail;
668
669 tbio = tbio->bi_next = bio;
670 DEBUG_IBLOCK("-----------------> Added +1 bio: %p to"
671 " list, Going to again\n", bio);
672 goto again;
673 }
674 /* Always in 512 byte units for Linux/Block */
675 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
676 sg_num--;
677 DEBUG_IBLOCK("task: %p bio-add_page() passed!, decremented"
678 " sg_num to %u\n", task, sg_num);
679 DEBUG_IBLOCK("task: %p bio_add_page() passed!, increased lba"
680 " to %llu\n", task, block_lba);
681 DEBUG_IBLOCK("task: %p bio_add_page() passed!, bio->bi_vcnt:"
682 " %u\n", task, bio->bi_vcnt);
683 }
684
685 return 0;
686 fail:
687 while (hbio) {
688 bio = hbio;
689 hbio = hbio->bi_next;
690 bio->bi_next = NULL;
691 bio_put(bio);
692 }
693 return ret;
694 }
695
696 static unsigned char *iblock_get_cdb(struct se_task *task)
697 {
698 return IBLOCK_REQ(task)->ib_scsi_cdb;
699 }
700
701 static u32 iblock_get_device_rev(struct se_device *dev)
702 {
703 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
704 }
705
706 static u32 iblock_get_device_type(struct se_device *dev)
707 {
708 return TYPE_DISK;
709 }
710
711 static sector_t iblock_get_blocks(struct se_device *dev)
712 {
713 struct iblock_dev *ibd = dev->dev_ptr;
714 struct block_device *bd = ibd->ibd_bd;
715 struct request_queue *q = bdev_get_queue(bd);
716
717 return iblock_emulate_read_cap_with_block_size(dev, bd, q);
718 }
719
720 static void iblock_bio_done(struct bio *bio, int err)
721 {
722 struct se_task *task = bio->bi_private;
723 struct iblock_req *ibr = IBLOCK_REQ(task);
724 /*
725 * Set -EIO if !BIO_UPTODATE and the passed is still err=0
726 */
727 if (!(test_bit(BIO_UPTODATE, &bio->bi_flags)) && !(err))
728 err = -EIO;
729
730 if (err != 0) {
731 printk(KERN_ERR "test_bit(BIO_UPTODATE) failed for bio: %p,"
732 " err: %d\n", bio, err);
733 /*
734 * Bump the ib_bio_err_cnt and release bio.
735 */
736 atomic_inc(&ibr->ib_bio_err_cnt);
737 smp_mb__after_atomic_inc();
738 bio_put(bio);
739 /*
740 * Wait to complete the task until the last bio as completed.
741 */
742 if (!(atomic_dec_and_test(&ibr->ib_bio_cnt)))
743 return;
744
745 ibr->ib_bio = NULL;
746 transport_complete_task(task, 0);
747 return;
748 }
749 DEBUG_IBLOCK("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n",
750 task, bio, task->task_lba, bio->bi_sector, err);
751 /*
752 * bio_put() will call iblock_bio_destructor() to release the bio back
753 * to ibr->ib_bio_set.
754 */
755 bio_put(bio);
756 /*
757 * Wait to complete the task until the last bio as completed.
758 */
759 if (!(atomic_dec_and_test(&ibr->ib_bio_cnt)))
760 return;
761 /*
762 * Return GOOD status for task if zero ib_bio_err_cnt exists.
763 */
764 ibr->ib_bio = NULL;
765 transport_complete_task(task, (!atomic_read(&ibr->ib_bio_err_cnt)));
766 }
767
768 static struct se_subsystem_api iblock_template = {
769 .name = "iblock",
770 .owner = THIS_MODULE,
771 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
772 .map_task_SG = iblock_map_task_SG,
773 .attach_hba = iblock_attach_hba,
774 .detach_hba = iblock_detach_hba,
775 .allocate_virtdevice = iblock_allocate_virtdevice,
776 .create_virtdevice = iblock_create_virtdevice,
777 .free_device = iblock_free_device,
778 .dpo_emulated = iblock_emulated_dpo,
779 .fua_write_emulated = iblock_emulated_fua_write,
780 .fua_read_emulated = iblock_emulated_fua_read,
781 .write_cache_emulated = iblock_emulated_write_cache,
782 .alloc_task = iblock_alloc_task,
783 .do_task = iblock_do_task,
784 .do_discard = iblock_do_discard,
785 .do_sync_cache = iblock_emulate_sync_cache,
786 .free_task = iblock_free_task,
787 .check_configfs_dev_params = iblock_check_configfs_dev_params,
788 .set_configfs_dev_params = iblock_set_configfs_dev_params,
789 .show_configfs_dev_params = iblock_show_configfs_dev_params,
790 .get_cdb = iblock_get_cdb,
791 .get_device_rev = iblock_get_device_rev,
792 .get_device_type = iblock_get_device_type,
793 .get_blocks = iblock_get_blocks,
794 };
795
796 static int __init iblock_module_init(void)
797 {
798 return transport_subsystem_register(&iblock_template);
799 }
800
801 static void iblock_module_exit(void)
802 {
803 transport_subsystem_release(&iblock_template);
804 }
805
806 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
807 MODULE_AUTHOR("nab@Linux-iSCSI.org");
808 MODULE_LICENSE("GPL");
809
810 module_init(iblock_module_init);
811 module_exit(iblock_module_exit);
kernel source for telekom puls (alcatel/mediatek)