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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*******************************************************************************
3 * Filename: target_core_file.c
4 *
5 * This file contains the Storage Engine <-> FILEIO transport specific functions
6 *
7 * (c) Copyright 2005-2013 Datera, Inc.
8 *
9 * Nicholas A. Bellinger <nab@kernel.org>
10 *
11 ******************************************************************************/
12
13#include <linux/string.h>
14#include <linux/parser.h>
15#include <linux/timer.h>
16#include <linux/blkdev.h>
17#include <linux/slab.h>
18#include <linux/spinlock.h>
19#include <linux/module.h>
20#include <linux/vmalloc.h>
21#include <linux/falloc.h>
22#include <linux/uio.h>
23#include <linux/scatterlist.h>
24#include <scsi/scsi_proto.h>
25#include <asm/unaligned.h>
26
27#include <target/target_core_base.h>
28#include <target/target_core_backend.h>
29
30#include "target_core_file.h"
31
32static inline struct fd_dev *FD_DEV(struct se_device *dev)
33{
34 return container_of(dev, struct fd_dev, dev);
35}
36
37static int fd_attach_hba(struct se_hba *hba, u32 host_id)
38{
39 struct fd_host *fd_host;
40
41 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
42 if (!fd_host) {
43 pr_err("Unable to allocate memory for struct fd_host\n");
44 return -ENOMEM;
45 }
46
47 fd_host->fd_host_id = host_id;
48
49 hba->hba_ptr = fd_host;
50
51 pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
52 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
53 TARGET_CORE_VERSION);
54 pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n",
55 hba->hba_id, fd_host->fd_host_id);
56
57 return 0;
58}
59
60static void fd_detach_hba(struct se_hba *hba)
61{
62 struct fd_host *fd_host = hba->hba_ptr;
63
64 pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
65 " Target Core\n", hba->hba_id, fd_host->fd_host_id);
66
67 kfree(fd_host);
68 hba->hba_ptr = NULL;
69}
70
71static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name)
72{
73 struct fd_dev *fd_dev;
74 struct fd_host *fd_host = hba->hba_ptr;
75
76 fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
77 if (!fd_dev) {
78 pr_err("Unable to allocate memory for struct fd_dev\n");
79 return NULL;
80 }
81
82 fd_dev->fd_host = fd_host;
83
84 pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
85
86 return &fd_dev->dev;
87}
88
89static bool fd_configure_unmap(struct se_device *dev)
90{
91 struct file *file = FD_DEV(dev)->fd_file;
92 struct inode *inode = file->f_mapping->host;
93
94 if (S_ISBLK(inode->i_mode))
95 return target_configure_unmap_from_queue(&dev->dev_attrib,
96 I_BDEV(inode));
97
98 /* Limit UNMAP emulation to 8k Number of LBAs (NoLB) */
99 dev->dev_attrib.max_unmap_lba_count = 0x2000;
100 /* Currently hardcoded to 1 in Linux/SCSI code. */
101 dev->dev_attrib.max_unmap_block_desc_count = 1;
102 dev->dev_attrib.unmap_granularity = 1;
103 dev->dev_attrib.unmap_granularity_alignment = 0;
104 return true;
105}
106
107static int fd_configure_device(struct se_device *dev)
108{
109 struct fd_dev *fd_dev = FD_DEV(dev);
110 struct fd_host *fd_host = dev->se_hba->hba_ptr;
111 struct file *file;
112 struct inode *inode = NULL;
113 int flags, ret = -EINVAL;
114
115 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
116 pr_err("Missing fd_dev_name=\n");
117 return -EINVAL;
118 }
119
120 /*
121 * Use O_DSYNC by default instead of O_SYNC to forgo syncing
122 * of pure timestamp updates.
123 */
124 flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
125
126 /*
127 * Optionally allow fd_buffered_io=1 to be enabled for people
128 * who want use the fs buffer cache as an WriteCache mechanism.
129 *
130 * This means that in event of a hard failure, there is a risk
131 * of silent data-loss if the SCSI client has *not* performed a
132 * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
133 * to write-out the entire device cache.
134 */
135 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
136 pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
137 flags &= ~O_DSYNC;
138 }
139
140 file = filp_open(fd_dev->fd_dev_name, flags, 0600);
141 if (IS_ERR(file)) {
142 pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
143 ret = PTR_ERR(file);
144 goto fail;
145 }
146 fd_dev->fd_file = file;
147 /*
148 * If using a block backend with this struct file, we extract
149 * fd_dev->fd_[block,dev]_size from struct block_device.
150 *
151 * Otherwise, we use the passed fd_size= from configfs
152 */
153 inode = file->f_mapping->host;
154 if (S_ISBLK(inode->i_mode)) {
155 struct block_device *bdev = I_BDEV(inode);
156 unsigned long long dev_size;
157
158 fd_dev->fd_block_size = bdev_logical_block_size(bdev);
159 /*
160 * Determine the number of bytes from i_size_read() minus
161 * one (1) logical sector from underlying struct block_device
162 */
163 dev_size = (i_size_read(file->f_mapping->host) -
164 fd_dev->fd_block_size);
165
166 pr_debug("FILEIO: Using size: %llu bytes from struct"
167 " block_device blocks: %llu logical_block_size: %d\n",
168 dev_size, div_u64(dev_size, fd_dev->fd_block_size),
169 fd_dev->fd_block_size);
170 /*
171 * Enable write same emulation for IBLOCK and use 0xFFFF as
172 * the smaller WRITE_SAME(10) only has a two-byte block count.
173 */
174 dev->dev_attrib.max_write_same_len = 0xFFFF;
175
176 if (bdev_nonrot(bdev))
177 dev->dev_attrib.is_nonrot = 1;
178 } else {
179 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
180 pr_err("FILEIO: Missing fd_dev_size="
181 " parameter, and no backing struct"
182 " block_device\n");
183 goto fail;
184 }
185
186 fd_dev->fd_block_size = FD_BLOCKSIZE;
187
188 /*
189 * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
190 * based upon struct iovec limit for vfs_writev()
191 */
192 dev->dev_attrib.max_write_same_len = 0x1000;
193 }
194
195 dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
196 dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
197 dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
198
199 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
200 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
201 " with FDBD_HAS_BUFFERED_IO_WCE\n");
202 dev->dev_attrib.emulate_write_cache = 1;
203 }
204
205 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
206 fd_dev->fd_queue_depth = dev->queue_depth;
207
208 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
209 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
210 fd_dev->fd_dev_name, fd_dev->fd_dev_size);
211
212 return 0;
213fail:
214 if (fd_dev->fd_file) {
215 filp_close(fd_dev->fd_file, NULL);
216 fd_dev->fd_file = NULL;
217 }
218 return ret;
219}
220
221static void fd_dev_call_rcu(struct rcu_head *p)
222{
223 struct se_device *dev = container_of(p, struct se_device, rcu_head);
224 struct fd_dev *fd_dev = FD_DEV(dev);
225
226 kfree(fd_dev);
227}
228
229static void fd_free_device(struct se_device *dev)
230{
231 call_rcu(&dev->rcu_head, fd_dev_call_rcu);
232}
233
234static void fd_destroy_device(struct se_device *dev)
235{
236 struct fd_dev *fd_dev = FD_DEV(dev);
237
238 if (fd_dev->fd_file) {
239 filp_close(fd_dev->fd_file, NULL);
240 fd_dev->fd_file = NULL;
241 }
242}
243
244struct target_core_file_cmd {
245 unsigned long len;
246 struct se_cmd *cmd;
247 struct kiocb iocb;
248 struct bio_vec bvecs[];
249};
250
251static void cmd_rw_aio_complete(struct kiocb *iocb, long ret)
252{
253 struct target_core_file_cmd *cmd;
254
255 cmd = container_of(iocb, struct target_core_file_cmd, iocb);
256
257 if (ret != cmd->len)
258 target_complete_cmd(cmd->cmd, SAM_STAT_CHECK_CONDITION);
259 else
260 target_complete_cmd(cmd->cmd, SAM_STAT_GOOD);
261
262 kfree(cmd);
263}
264
265static sense_reason_t
266fd_execute_rw_aio(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
267 enum dma_data_direction data_direction)
268{
269 int is_write = !(data_direction == DMA_FROM_DEVICE);
270 struct se_device *dev = cmd->se_dev;
271 struct fd_dev *fd_dev = FD_DEV(dev);
272 struct file *file = fd_dev->fd_file;
273 struct target_core_file_cmd *aio_cmd;
274 struct iov_iter iter;
275 struct scatterlist *sg;
276 ssize_t len = 0;
277 int ret = 0, i;
278
279 aio_cmd = kmalloc(struct_size(aio_cmd, bvecs, sgl_nents), GFP_KERNEL);
280 if (!aio_cmd)
281 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
282
283 for_each_sg(sgl, sg, sgl_nents, i) {
284 bvec_set_page(&aio_cmd->bvecs[i], sg_page(sg), sg->length,
285 sg->offset);
286 len += sg->length;
287 }
288
289 iov_iter_bvec(&iter, is_write, aio_cmd->bvecs, sgl_nents, len);
290
291 aio_cmd->cmd = cmd;
292 aio_cmd->len = len;
293 aio_cmd->iocb.ki_pos = cmd->t_task_lba * dev->dev_attrib.block_size;
294 aio_cmd->iocb.ki_filp = file;
295 aio_cmd->iocb.ki_complete = cmd_rw_aio_complete;
296 aio_cmd->iocb.ki_flags = IOCB_DIRECT;
297
298 if (is_write && (cmd->se_cmd_flags & SCF_FUA))
299 aio_cmd->iocb.ki_flags |= IOCB_DSYNC;
300
301 if (is_write)
302 ret = call_write_iter(file, &aio_cmd->iocb, &iter);
303 else
304 ret = call_read_iter(file, &aio_cmd->iocb, &iter);
305
306 if (ret != -EIOCBQUEUED)
307 cmd_rw_aio_complete(&aio_cmd->iocb, ret);
308
309 return 0;
310}
311
312static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
313 u32 block_size, struct scatterlist *sgl,
314 u32 sgl_nents, u32 data_length, int is_write)
315{
316 struct scatterlist *sg;
317 struct iov_iter iter;
318 struct bio_vec *bvec;
319 ssize_t len = 0;
320 loff_t pos = (cmd->t_task_lba * block_size);
321 int ret = 0, i;
322
323 bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
324 if (!bvec) {
325 pr_err("Unable to allocate fd_do_readv iov[]\n");
326 return -ENOMEM;
327 }
328
329 for_each_sg(sgl, sg, sgl_nents, i) {
330 bvec_set_page(&bvec[i], sg_page(sg), sg->length, sg->offset);
331 len += sg->length;
332 }
333
334 iov_iter_bvec(&iter, is_write, bvec, sgl_nents, len);
335 if (is_write)
336 ret = vfs_iter_write(fd, &iter, &pos, 0);
337 else
338 ret = vfs_iter_read(fd, &iter, &pos, 0);
339
340 if (is_write) {
341 if (ret < 0 || ret != data_length) {
342 pr_err("%s() write returned %d\n", __func__, ret);
343 if (ret >= 0)
344 ret = -EINVAL;
345 }
346 } else {
347 /*
348 * Return zeros and GOOD status even if the READ did not return
349 * the expected virt_size for struct file w/o a backing struct
350 * block_device.
351 */
352 if (S_ISBLK(file_inode(fd)->i_mode)) {
353 if (ret < 0 || ret != data_length) {
354 pr_err("%s() returned %d, expecting %u for "
355 "S_ISBLK\n", __func__, ret,
356 data_length);
357 if (ret >= 0)
358 ret = -EINVAL;
359 }
360 } else {
361 if (ret < 0) {
362 pr_err("%s() returned %d for non S_ISBLK\n",
363 __func__, ret);
364 } else if (ret != data_length) {
365 /*
366 * Short read case:
367 * Probably some one truncate file under us.
368 * We must explicitly zero sg-pages to prevent
369 * expose uninizialized pages to userspace.
370 */
371 if (ret < data_length)
372 ret += iov_iter_zero(data_length - ret, &iter);
373 else
374 ret = -EINVAL;
375 }
376 }
377 }
378 kfree(bvec);
379 return ret;
380}
381
382static sense_reason_t
383fd_execute_sync_cache(struct se_cmd *cmd)
384{
385 struct se_device *dev = cmd->se_dev;
386 struct fd_dev *fd_dev = FD_DEV(dev);
387 int immed = (cmd->t_task_cdb[1] & 0x2);
388 loff_t start, end;
389 int ret;
390
391 /*
392 * If the Immediate bit is set, queue up the GOOD response
393 * for this SYNCHRONIZE_CACHE op
394 */
395 if (immed)
396 target_complete_cmd(cmd, SAM_STAT_GOOD);
397
398 /*
399 * Determine if we will be flushing the entire device.
400 */
401 if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
402 start = 0;
403 end = LLONG_MAX;
404 } else {
405 start = cmd->t_task_lba * dev->dev_attrib.block_size;
406 if (cmd->data_length)
407 end = start + cmd->data_length - 1;
408 else
409 end = LLONG_MAX;
410 }
411
412 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
413 if (ret != 0)
414 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
415
416 if (immed)
417 return 0;
418
419 if (ret)
420 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
421 else
422 target_complete_cmd(cmd, SAM_STAT_GOOD);
423
424 return 0;
425}
426
427static sense_reason_t
428fd_execute_write_same(struct se_cmd *cmd)
429{
430 struct se_device *se_dev = cmd->se_dev;
431 struct fd_dev *fd_dev = FD_DEV(se_dev);
432 loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
433 sector_t nolb = sbc_get_write_same_sectors(cmd);
434 struct iov_iter iter;
435 struct bio_vec *bvec;
436 unsigned int len = 0, i;
437 ssize_t ret;
438
439 if (cmd->prot_op) {
440 pr_err("WRITE_SAME: Protection information with FILEIO"
441 " backends not supported\n");
442 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
443 }
444
445 if (!cmd->t_data_nents)
446 return TCM_INVALID_CDB_FIELD;
447
448 if (cmd->t_data_nents > 1 ||
449 cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
450 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
451 " block_size: %u\n",
452 cmd->t_data_nents,
453 cmd->t_data_sg[0].length,
454 cmd->se_dev->dev_attrib.block_size);
455 return TCM_INVALID_CDB_FIELD;
456 }
457
458 bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
459 if (!bvec)
460 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
461
462 for (i = 0; i < nolb; i++) {
463 bvec_set_page(&bvec[i], sg_page(&cmd->t_data_sg[0]),
464 cmd->t_data_sg[0].length,
465 cmd->t_data_sg[0].offset);
466 len += se_dev->dev_attrib.block_size;
467 }
468
469 iov_iter_bvec(&iter, ITER_SOURCE, bvec, nolb, len);
470 ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0);
471
472 kfree(bvec);
473 if (ret < 0 || ret != len) {
474 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
475 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
476 }
477
478 target_complete_cmd(cmd, SAM_STAT_GOOD);
479 return 0;
480}
481
482static int
483fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
484 void *buf, size_t bufsize)
485{
486 struct fd_dev *fd_dev = FD_DEV(se_dev);
487 struct file *prot_fd = fd_dev->fd_prot_file;
488 sector_t prot_length, prot;
489 loff_t pos = lba * se_dev->prot_length;
490
491 if (!prot_fd) {
492 pr_err("Unable to locate fd_dev->fd_prot_file\n");
493 return -ENODEV;
494 }
495
496 prot_length = nolb * se_dev->prot_length;
497
498 memset(buf, 0xff, bufsize);
499 for (prot = 0; prot < prot_length;) {
500 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
501 ssize_t ret = kernel_write(prot_fd, buf, len, &pos);
502
503 if (ret != len) {
504 pr_err("vfs_write to prot file failed: %zd\n", ret);
505 return ret < 0 ? ret : -ENODEV;
506 }
507 prot += ret;
508 }
509
510 return 0;
511}
512
513static int
514fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
515{
516 void *buf;
517 int rc;
518
519 buf = (void *)__get_free_page(GFP_KERNEL);
520 if (!buf) {
521 pr_err("Unable to allocate FILEIO prot buf\n");
522 return -ENOMEM;
523 }
524
525 rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
526
527 free_page((unsigned long)buf);
528
529 return rc;
530}
531
532static sense_reason_t
533fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
534{
535 struct file *file = FD_DEV(cmd->se_dev)->fd_file;
536 struct inode *inode = file->f_mapping->host;
537 int ret;
538
539 if (!nolb) {
540 return 0;
541 }
542
543 if (cmd->se_dev->dev_attrib.pi_prot_type) {
544 ret = fd_do_prot_unmap(cmd, lba, nolb);
545 if (ret)
546 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
547 }
548
549 if (S_ISBLK(inode->i_mode)) {
550 /* The backend is block device, use discard */
551 struct block_device *bdev = I_BDEV(inode);
552 struct se_device *dev = cmd->se_dev;
553
554 ret = blkdev_issue_discard(bdev,
555 target_to_linux_sector(dev, lba),
556 target_to_linux_sector(dev, nolb),
557 GFP_KERNEL);
558 if (ret < 0) {
559 pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
560 ret);
561 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
562 }
563 } else {
564 /* The backend is normal file, use fallocate */
565 struct se_device *se_dev = cmd->se_dev;
566 loff_t pos = lba * se_dev->dev_attrib.block_size;
567 unsigned int len = nolb * se_dev->dev_attrib.block_size;
568 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
569
570 if (!file->f_op->fallocate)
571 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
572
573 ret = file->f_op->fallocate(file, mode, pos, len);
574 if (ret < 0) {
575 pr_warn("FILEIO: fallocate() failed: %d\n", ret);
576 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
577 }
578 }
579
580 return 0;
581}
582
583static sense_reason_t
584fd_execute_rw_buffered(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
585 enum dma_data_direction data_direction)
586{
587 struct se_device *dev = cmd->se_dev;
588 struct fd_dev *fd_dev = FD_DEV(dev);
589 struct file *file = fd_dev->fd_file;
590 struct file *pfile = fd_dev->fd_prot_file;
591 sense_reason_t rc;
592 int ret = 0;
593 /*
594 * Call vectorized fileio functions to map struct scatterlist
595 * physical memory addresses to struct iovec virtual memory.
596 */
597 if (data_direction == DMA_FROM_DEVICE) {
598 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
599 ret = fd_do_rw(cmd, pfile, dev->prot_length,
600 cmd->t_prot_sg, cmd->t_prot_nents,
601 cmd->prot_length, 0);
602 if (ret < 0)
603 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
604 }
605
606 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
607 sgl, sgl_nents, cmd->data_length, 0);
608
609 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type &&
610 dev->dev_attrib.pi_prot_verify) {
611 u32 sectors = cmd->data_length >>
612 ilog2(dev->dev_attrib.block_size);
613
614 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
615 0, cmd->t_prot_sg, 0);
616 if (rc)
617 return rc;
618 }
619 } else {
620 if (cmd->prot_type && dev->dev_attrib.pi_prot_type &&
621 dev->dev_attrib.pi_prot_verify) {
622 u32 sectors = cmd->data_length >>
623 ilog2(dev->dev_attrib.block_size);
624
625 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
626 0, cmd->t_prot_sg, 0);
627 if (rc)
628 return rc;
629 }
630
631 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
632 sgl, sgl_nents, cmd->data_length, 1);
633 /*
634 * Perform implicit vfs_fsync_range() for fd_do_writev() ops
635 * for SCSI WRITEs with Forced Unit Access (FUA) set.
636 * Allow this to happen independent of WCE=0 setting.
637 */
638 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
639 loff_t start = cmd->t_task_lba *
640 dev->dev_attrib.block_size;
641 loff_t end;
642
643 if (cmd->data_length)
644 end = start + cmd->data_length - 1;
645 else
646 end = LLONG_MAX;
647
648 vfs_fsync_range(fd_dev->fd_file, start, end, 1);
649 }
650
651 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
652 ret = fd_do_rw(cmd, pfile, dev->prot_length,
653 cmd->t_prot_sg, cmd->t_prot_nents,
654 cmd->prot_length, 1);
655 if (ret < 0)
656 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
657 }
658 }
659
660 if (ret < 0)
661 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
662
663 target_complete_cmd(cmd, SAM_STAT_GOOD);
664 return 0;
665}
666
667static sense_reason_t
668fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
669 enum dma_data_direction data_direction)
670{
671 struct se_device *dev = cmd->se_dev;
672 struct fd_dev *fd_dev = FD_DEV(dev);
673
674 /*
675 * We are currently limited by the number of iovecs (2048) per
676 * single vfs_[writev,readv] call.
677 */
678 if (cmd->data_length > FD_MAX_BYTES) {
679 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
680 "FD_MAX_BYTES: %u iovec count limitation\n",
681 cmd->data_length, FD_MAX_BYTES);
682 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
683 }
684
685 if (fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO)
686 return fd_execute_rw_aio(cmd, sgl, sgl_nents, data_direction);
687 return fd_execute_rw_buffered(cmd, sgl, sgl_nents, data_direction);
688}
689
690enum {
691 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io,
692 Opt_fd_async_io, Opt_err
693};
694
695static match_table_t tokens = {
696 {Opt_fd_dev_name, "fd_dev_name=%s"},
697 {Opt_fd_dev_size, "fd_dev_size=%s"},
698 {Opt_fd_buffered_io, "fd_buffered_io=%d"},
699 {Opt_fd_async_io, "fd_async_io=%d"},
700 {Opt_err, NULL}
701};
702
703static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
704 const char *page, ssize_t count)
705{
706 struct fd_dev *fd_dev = FD_DEV(dev);
707 char *orig, *ptr, *arg_p, *opts;
708 substring_t args[MAX_OPT_ARGS];
709 int ret = 0, arg, token;
710
711 opts = kstrdup(page, GFP_KERNEL);
712 if (!opts)
713 return -ENOMEM;
714
715 orig = opts;
716
717 while ((ptr = strsep(&opts, ",\n")) != NULL) {
718 if (!*ptr)
719 continue;
720
721 token = match_token(ptr, tokens, args);
722 switch (token) {
723 case Opt_fd_dev_name:
724 if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
725 FD_MAX_DEV_NAME) == 0) {
726 ret = -EINVAL;
727 break;
728 }
729 pr_debug("FILEIO: Referencing Path: %s\n",
730 fd_dev->fd_dev_name);
731 fd_dev->fbd_flags |= FBDF_HAS_PATH;
732 break;
733 case Opt_fd_dev_size:
734 arg_p = match_strdup(&args[0]);
735 if (!arg_p) {
736 ret = -ENOMEM;
737 break;
738 }
739 ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
740 kfree(arg_p);
741 if (ret < 0) {
742 pr_err("kstrtoull() failed for"
743 " fd_dev_size=\n");
744 goto out;
745 }
746 pr_debug("FILEIO: Referencing Size: %llu"
747 " bytes\n", fd_dev->fd_dev_size);
748 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
749 break;
750 case Opt_fd_buffered_io:
751 ret = match_int(args, &arg);
752 if (ret)
753 goto out;
754 if (arg != 1) {
755 pr_err("bogus fd_buffered_io=%d value\n", arg);
756 ret = -EINVAL;
757 goto out;
758 }
759
760 pr_debug("FILEIO: Using buffered I/O"
761 " operations for struct fd_dev\n");
762
763 fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
764 break;
765 case Opt_fd_async_io:
766 ret = match_int(args, &arg);
767 if (ret)
768 goto out;
769 if (arg != 1) {
770 pr_err("bogus fd_async_io=%d value\n", arg);
771 ret = -EINVAL;
772 goto out;
773 }
774
775 pr_debug("FILEIO: Using async I/O"
776 " operations for struct fd_dev\n");
777
778 fd_dev->fbd_flags |= FDBD_HAS_ASYNC_IO;
779 break;
780 default:
781 break;
782 }
783 }
784
785out:
786 kfree(orig);
787 return (!ret) ? count : ret;
788}
789
790static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
791{
792 struct fd_dev *fd_dev = FD_DEV(dev);
793 ssize_t bl = 0;
794
795 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
796 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s Async: %d\n",
797 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
798 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
799 "Buffered-WCE" : "O_DSYNC",
800 !!(fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO));
801 return bl;
802}
803
804static sector_t fd_get_blocks(struct se_device *dev)
805{
806 struct fd_dev *fd_dev = FD_DEV(dev);
807 struct file *f = fd_dev->fd_file;
808 struct inode *i = f->f_mapping->host;
809 unsigned long long dev_size;
810 /*
811 * When using a file that references an underlying struct block_device,
812 * ensure dev_size is always based on the current inode size in order
813 * to handle underlying block_device resize operations.
814 */
815 if (S_ISBLK(i->i_mode))
816 dev_size = i_size_read(i);
817 else
818 dev_size = fd_dev->fd_dev_size;
819
820 return div_u64(dev_size - dev->dev_attrib.block_size,
821 dev->dev_attrib.block_size);
822}
823
824static int fd_init_prot(struct se_device *dev)
825{
826 struct fd_dev *fd_dev = FD_DEV(dev);
827 struct file *prot_file, *file = fd_dev->fd_file;
828 struct inode *inode;
829 int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
830 char buf[FD_MAX_DEV_PROT_NAME];
831
832 if (!file) {
833 pr_err("Unable to locate fd_dev->fd_file\n");
834 return -ENODEV;
835 }
836
837 inode = file->f_mapping->host;
838 if (S_ISBLK(inode->i_mode)) {
839 pr_err("FILEIO Protection emulation only supported on"
840 " !S_ISBLK\n");
841 return -ENOSYS;
842 }
843
844 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
845 flags &= ~O_DSYNC;
846
847 snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
848 fd_dev->fd_dev_name);
849
850 prot_file = filp_open(buf, flags, 0600);
851 if (IS_ERR(prot_file)) {
852 pr_err("filp_open(%s) failed\n", buf);
853 ret = PTR_ERR(prot_file);
854 return ret;
855 }
856 fd_dev->fd_prot_file = prot_file;
857
858 return 0;
859}
860
861static int fd_format_prot(struct se_device *dev)
862{
863 unsigned char *buf;
864 int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
865 int ret;
866
867 if (!dev->dev_attrib.pi_prot_type) {
868 pr_err("Unable to format_prot while pi_prot_type == 0\n");
869 return -ENODEV;
870 }
871
872 buf = vzalloc(unit_size);
873 if (!buf) {
874 pr_err("Unable to allocate FILEIO prot buf\n");
875 return -ENOMEM;
876 }
877
878 pr_debug("Using FILEIO prot_length: %llu\n",
879 (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
880 dev->prot_length);
881
882 ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
883 buf, unit_size);
884 vfree(buf);
885 return ret;
886}
887
888static void fd_free_prot(struct se_device *dev)
889{
890 struct fd_dev *fd_dev = FD_DEV(dev);
891
892 if (!fd_dev->fd_prot_file)
893 return;
894
895 filp_close(fd_dev->fd_prot_file, NULL);
896 fd_dev->fd_prot_file = NULL;
897}
898
899static struct exec_cmd_ops fd_exec_cmd_ops = {
900 .execute_rw = fd_execute_rw,
901 .execute_sync_cache = fd_execute_sync_cache,
902 .execute_write_same = fd_execute_write_same,
903 .execute_unmap = fd_execute_unmap,
904};
905
906static sense_reason_t
907fd_parse_cdb(struct se_cmd *cmd)
908{
909 return sbc_parse_cdb(cmd, &fd_exec_cmd_ops);
910}
911
912static const struct target_backend_ops fileio_ops = {
913 .name = "fileio",
914 .inquiry_prod = "FILEIO",
915 .inquiry_rev = FD_VERSION,
916 .owner = THIS_MODULE,
917 .attach_hba = fd_attach_hba,
918 .detach_hba = fd_detach_hba,
919 .alloc_device = fd_alloc_device,
920 .configure_device = fd_configure_device,
921 .destroy_device = fd_destroy_device,
922 .free_device = fd_free_device,
923 .configure_unmap = fd_configure_unmap,
924 .parse_cdb = fd_parse_cdb,
925 .set_configfs_dev_params = fd_set_configfs_dev_params,
926 .show_configfs_dev_params = fd_show_configfs_dev_params,
927 .get_device_type = sbc_get_device_type,
928 .get_blocks = fd_get_blocks,
929 .init_prot = fd_init_prot,
930 .format_prot = fd_format_prot,
931 .free_prot = fd_free_prot,
932 .tb_dev_attrib_attrs = sbc_attrib_attrs,
933};
934
935static int __init fileio_module_init(void)
936{
937 return transport_backend_register(&fileio_ops);
938}
939
940static void __exit fileio_module_exit(void)
941{
942 target_backend_unregister(&fileio_ops);
943}
944
945MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
946MODULE_AUTHOR("nab@Linux-iSCSI.org");
947MODULE_LICENSE("GPL");
948
949module_init(fileio_module_init);
950module_exit(fileio_module_exit);
1/*******************************************************************************
2 * Filename: target_core_file.c
3 *
4 * This file contains the Storage Engine <-> FILEIO transport specific functions
5 *
6 * Copyright (c) 2005 PyX Technologies, Inc.
7 * Copyright (c) 2005-2006 SBE, Inc. All Rights Reserved.
8 * Copyright (c) 2007-2010 Rising Tide Systems
9 * Copyright (c) 2008-2010 Linux-iSCSI.org
10 *
11 * Nicholas A. Bellinger <nab@kernel.org>
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
17 *
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26 *
27 ******************************************************************************/
28
29#include <linux/string.h>
30#include <linux/parser.h>
31#include <linux/timer.h>
32#include <linux/blkdev.h>
33#include <linux/slab.h>
34#include <linux/spinlock.h>
35#include <linux/module.h>
36#include <scsi/scsi.h>
37#include <scsi/scsi_host.h>
38
39#include <target/target_core_base.h>
40#include <target/target_core_backend.h>
41
42#include "target_core_file.h"
43
44static struct se_subsystem_api fileio_template;
45
46/* fd_attach_hba(): (Part of se_subsystem_api_t template)
47 *
48 *
49 */
50static int fd_attach_hba(struct se_hba *hba, u32 host_id)
51{
52 struct fd_host *fd_host;
53
54 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
55 if (!fd_host) {
56 pr_err("Unable to allocate memory for struct fd_host\n");
57 return -ENOMEM;
58 }
59
60 fd_host->fd_host_id = host_id;
61
62 hba->hba_ptr = fd_host;
63
64 pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
65 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
66 TARGET_CORE_MOD_VERSION);
67 pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic"
68 " MaxSectors: %u\n",
69 hba->hba_id, fd_host->fd_host_id, FD_MAX_SECTORS);
70
71 return 0;
72}
73
74static void fd_detach_hba(struct se_hba *hba)
75{
76 struct fd_host *fd_host = hba->hba_ptr;
77
78 pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
79 " Target Core\n", hba->hba_id, fd_host->fd_host_id);
80
81 kfree(fd_host);
82 hba->hba_ptr = NULL;
83}
84
85static void *fd_allocate_virtdevice(struct se_hba *hba, const char *name)
86{
87 struct fd_dev *fd_dev;
88 struct fd_host *fd_host = hba->hba_ptr;
89
90 fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
91 if (!fd_dev) {
92 pr_err("Unable to allocate memory for struct fd_dev\n");
93 return NULL;
94 }
95
96 fd_dev->fd_host = fd_host;
97
98 pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
99
100 return fd_dev;
101}
102
103/* fd_create_virtdevice(): (Part of se_subsystem_api_t template)
104 *
105 *
106 */
107static struct se_device *fd_create_virtdevice(
108 struct se_hba *hba,
109 struct se_subsystem_dev *se_dev,
110 void *p)
111{
112 char *dev_p = NULL;
113 struct se_device *dev;
114 struct se_dev_limits dev_limits;
115 struct queue_limits *limits;
116 struct fd_dev *fd_dev = p;
117 struct fd_host *fd_host = hba->hba_ptr;
118 mm_segment_t old_fs;
119 struct file *file;
120 struct inode *inode = NULL;
121 int dev_flags = 0, flags, ret = -EINVAL;
122
123 memset(&dev_limits, 0, sizeof(struct se_dev_limits));
124
125 old_fs = get_fs();
126 set_fs(get_ds());
127 dev_p = getname(fd_dev->fd_dev_name);
128 set_fs(old_fs);
129
130 if (IS_ERR(dev_p)) {
131 pr_err("getname(%s) failed: %lu\n",
132 fd_dev->fd_dev_name, IS_ERR(dev_p));
133 ret = PTR_ERR(dev_p);
134 goto fail;
135 }
136 /*
137 * Use O_DSYNC by default instead of O_SYNC to forgo syncing
138 * of pure timestamp updates.
139 */
140 flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
141
142 file = filp_open(dev_p, flags, 0600);
143 if (IS_ERR(file)) {
144 pr_err("filp_open(%s) failed\n", dev_p);
145 ret = PTR_ERR(file);
146 goto fail;
147 }
148 if (!file || !file->f_dentry) {
149 pr_err("filp_open(%s) failed\n", dev_p);
150 goto fail;
151 }
152 fd_dev->fd_file = file;
153 /*
154 * If using a block backend with this struct file, we extract
155 * fd_dev->fd_[block,dev]_size from struct block_device.
156 *
157 * Otherwise, we use the passed fd_size= from configfs
158 */
159 inode = file->f_mapping->host;
160 if (S_ISBLK(inode->i_mode)) {
161 struct request_queue *q;
162 unsigned long long dev_size;
163 /*
164 * Setup the local scope queue_limits from struct request_queue->limits
165 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
166 */
167 q = bdev_get_queue(inode->i_bdev);
168 limits = &dev_limits.limits;
169 limits->logical_block_size = bdev_logical_block_size(inode->i_bdev);
170 limits->max_hw_sectors = queue_max_hw_sectors(q);
171 limits->max_sectors = queue_max_sectors(q);
172 /*
173 * Determine the number of bytes from i_size_read() minus
174 * one (1) logical sector from underlying struct block_device
175 */
176 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
177 dev_size = (i_size_read(file->f_mapping->host) -
178 fd_dev->fd_block_size);
179
180 pr_debug("FILEIO: Using size: %llu bytes from struct"
181 " block_device blocks: %llu logical_block_size: %d\n",
182 dev_size, div_u64(dev_size, fd_dev->fd_block_size),
183 fd_dev->fd_block_size);
184 } else {
185 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
186 pr_err("FILEIO: Missing fd_dev_size="
187 " parameter, and no backing struct"
188 " block_device\n");
189 goto fail;
190 }
191
192 limits = &dev_limits.limits;
193 limits->logical_block_size = FD_BLOCKSIZE;
194 limits->max_hw_sectors = FD_MAX_SECTORS;
195 limits->max_sectors = FD_MAX_SECTORS;
196 fd_dev->fd_block_size = FD_BLOCKSIZE;
197 }
198
199 dev_limits.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
200 dev_limits.queue_depth = FD_DEVICE_QUEUE_DEPTH;
201
202 dev = transport_add_device_to_core_hba(hba, &fileio_template,
203 se_dev, dev_flags, fd_dev,
204 &dev_limits, "FILEIO", FD_VERSION);
205 if (!dev)
206 goto fail;
207
208 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
209 fd_dev->fd_queue_depth = dev->queue_depth;
210
211 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
212 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
213 fd_dev->fd_dev_name, fd_dev->fd_dev_size);
214
215 putname(dev_p);
216 return dev;
217fail:
218 if (fd_dev->fd_file) {
219 filp_close(fd_dev->fd_file, NULL);
220 fd_dev->fd_file = NULL;
221 }
222 putname(dev_p);
223 return ERR_PTR(ret);
224}
225
226/* fd_free_device(): (Part of se_subsystem_api_t template)
227 *
228 *
229 */
230static void fd_free_device(void *p)
231{
232 struct fd_dev *fd_dev = p;
233
234 if (fd_dev->fd_file) {
235 filp_close(fd_dev->fd_file, NULL);
236 fd_dev->fd_file = NULL;
237 }
238
239 kfree(fd_dev);
240}
241
242static int fd_do_readv(struct se_cmd *cmd, struct scatterlist *sgl,
243 u32 sgl_nents)
244{
245 struct se_device *se_dev = cmd->se_dev;
246 struct fd_dev *dev = se_dev->dev_ptr;
247 struct file *fd = dev->fd_file;
248 struct scatterlist *sg;
249 struct iovec *iov;
250 mm_segment_t old_fs;
251 loff_t pos = (cmd->t_task_lba *
252 se_dev->se_sub_dev->se_dev_attrib.block_size);
253 int ret = 0, i;
254
255 iov = kzalloc(sizeof(struct iovec) * sgl_nents, GFP_KERNEL);
256 if (!iov) {
257 pr_err("Unable to allocate fd_do_readv iov[]\n");
258 return -ENOMEM;
259 }
260
261 for_each_sg(sgl, sg, sgl_nents, i) {
262 iov[i].iov_len = sg->length;
263 iov[i].iov_base = sg_virt(sg);
264 }
265
266 old_fs = get_fs();
267 set_fs(get_ds());
268 ret = vfs_readv(fd, &iov[0], sgl_nents, &pos);
269 set_fs(old_fs);
270
271 kfree(iov);
272 /*
273 * Return zeros and GOOD status even if the READ did not return
274 * the expected virt_size for struct file w/o a backing struct
275 * block_device.
276 */
277 if (S_ISBLK(fd->f_dentry->d_inode->i_mode)) {
278 if (ret < 0 || ret != cmd->data_length) {
279 pr_err("vfs_readv() returned %d,"
280 " expecting %d for S_ISBLK\n", ret,
281 (int)cmd->data_length);
282 return (ret < 0 ? ret : -EINVAL);
283 }
284 } else {
285 if (ret < 0) {
286 pr_err("vfs_readv() returned %d for non"
287 " S_ISBLK\n", ret);
288 return ret;
289 }
290 }
291
292 return 1;
293}
294
295static int fd_do_writev(struct se_cmd *cmd, struct scatterlist *sgl,
296 u32 sgl_nents)
297{
298 struct se_device *se_dev = cmd->se_dev;
299 struct fd_dev *dev = se_dev->dev_ptr;
300 struct file *fd = dev->fd_file;
301 struct scatterlist *sg;
302 struct iovec *iov;
303 mm_segment_t old_fs;
304 loff_t pos = (cmd->t_task_lba *
305 se_dev->se_sub_dev->se_dev_attrib.block_size);
306 int ret, i = 0;
307
308 iov = kzalloc(sizeof(struct iovec) * sgl_nents, GFP_KERNEL);
309 if (!iov) {
310 pr_err("Unable to allocate fd_do_writev iov[]\n");
311 return -ENOMEM;
312 }
313
314 for_each_sg(sgl, sg, sgl_nents, i) {
315 iov[i].iov_len = sg->length;
316 iov[i].iov_base = sg_virt(sg);
317 }
318
319 old_fs = get_fs();
320 set_fs(get_ds());
321 ret = vfs_writev(fd, &iov[0], sgl_nents, &pos);
322 set_fs(old_fs);
323
324 kfree(iov);
325
326 if (ret < 0 || ret != cmd->data_length) {
327 pr_err("vfs_writev() returned %d\n", ret);
328 return (ret < 0 ? ret : -EINVAL);
329 }
330
331 return 1;
332}
333
334static void fd_emulate_sync_cache(struct se_cmd *cmd)
335{
336 struct se_device *dev = cmd->se_dev;
337 struct fd_dev *fd_dev = dev->dev_ptr;
338 int immed = (cmd->t_task_cdb[1] & 0x2);
339 loff_t start, end;
340 int ret;
341
342 /*
343 * If the Immediate bit is set, queue up the GOOD response
344 * for this SYNCHRONIZE_CACHE op
345 */
346 if (immed)
347 target_complete_cmd(cmd, SAM_STAT_GOOD);
348
349 /*
350 * Determine if we will be flushing the entire device.
351 */
352 if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
353 start = 0;
354 end = LLONG_MAX;
355 } else {
356 start = cmd->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
357 if (cmd->data_length)
358 end = start + cmd->data_length;
359 else
360 end = LLONG_MAX;
361 }
362
363 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
364 if (ret != 0)
365 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
366
367 if (immed)
368 return;
369
370 if (ret) {
371 cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
372 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
373 } else {
374 target_complete_cmd(cmd, SAM_STAT_GOOD);
375 }
376}
377
378static int fd_execute_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
379 u32 sgl_nents, enum dma_data_direction data_direction)
380{
381 struct se_device *dev = cmd->se_dev;
382 int ret = 0;
383
384 /*
385 * Call vectorized fileio functions to map struct scatterlist
386 * physical memory addresses to struct iovec virtual memory.
387 */
388 if (data_direction == DMA_FROM_DEVICE) {
389 ret = fd_do_readv(cmd, sgl, sgl_nents);
390 } else {
391 ret = fd_do_writev(cmd, sgl, sgl_nents);
392 /*
393 * Perform implict vfs_fsync_range() for fd_do_writev() ops
394 * for SCSI WRITEs with Forced Unit Access (FUA) set.
395 * Allow this to happen independent of WCE=0 setting.
396 */
397 if (ret > 0 &&
398 dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
399 (cmd->se_cmd_flags & SCF_FUA)) {
400 struct fd_dev *fd_dev = dev->dev_ptr;
401 loff_t start = cmd->t_task_lba *
402 dev->se_sub_dev->se_dev_attrib.block_size;
403 loff_t end = start + cmd->data_length;
404
405 vfs_fsync_range(fd_dev->fd_file, start, end, 1);
406 }
407 }
408
409 if (ret < 0) {
410 cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
411 return ret;
412 }
413 if (ret)
414 target_complete_cmd(cmd, SAM_STAT_GOOD);
415 return 0;
416}
417
418enum {
419 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
420};
421
422static match_table_t tokens = {
423 {Opt_fd_dev_name, "fd_dev_name=%s"},
424 {Opt_fd_dev_size, "fd_dev_size=%s"},
425 {Opt_err, NULL}
426};
427
428static ssize_t fd_set_configfs_dev_params(
429 struct se_hba *hba,
430 struct se_subsystem_dev *se_dev,
431 const char *page, ssize_t count)
432{
433 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
434 char *orig, *ptr, *arg_p, *opts;
435 substring_t args[MAX_OPT_ARGS];
436 int ret = 0, token;
437
438 opts = kstrdup(page, GFP_KERNEL);
439 if (!opts)
440 return -ENOMEM;
441
442 orig = opts;
443
444 while ((ptr = strsep(&opts, ",\n")) != NULL) {
445 if (!*ptr)
446 continue;
447
448 token = match_token(ptr, tokens, args);
449 switch (token) {
450 case Opt_fd_dev_name:
451 arg_p = match_strdup(&args[0]);
452 if (!arg_p) {
453 ret = -ENOMEM;
454 break;
455 }
456 snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME,
457 "%s", arg_p);
458 kfree(arg_p);
459 pr_debug("FILEIO: Referencing Path: %s\n",
460 fd_dev->fd_dev_name);
461 fd_dev->fbd_flags |= FBDF_HAS_PATH;
462 break;
463 case Opt_fd_dev_size:
464 arg_p = match_strdup(&args[0]);
465 if (!arg_p) {
466 ret = -ENOMEM;
467 break;
468 }
469 ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size);
470 kfree(arg_p);
471 if (ret < 0) {
472 pr_err("strict_strtoull() failed for"
473 " fd_dev_size=\n");
474 goto out;
475 }
476 pr_debug("FILEIO: Referencing Size: %llu"
477 " bytes\n", fd_dev->fd_dev_size);
478 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
479 break;
480 default:
481 break;
482 }
483 }
484
485out:
486 kfree(orig);
487 return (!ret) ? count : ret;
488}
489
490static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev)
491{
492 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
493
494 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
495 pr_err("Missing fd_dev_name=\n");
496 return -EINVAL;
497 }
498
499 return 0;
500}
501
502static ssize_t fd_show_configfs_dev_params(
503 struct se_hba *hba,
504 struct se_subsystem_dev *se_dev,
505 char *b)
506{
507 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
508 ssize_t bl = 0;
509
510 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
511 bl += sprintf(b + bl, " File: %s Size: %llu Mode: O_DSYNC\n",
512 fd_dev->fd_dev_name, fd_dev->fd_dev_size);
513 return bl;
514}
515
516/* fd_get_device_rev(): (Part of se_subsystem_api_t template)
517 *
518 *
519 */
520static u32 fd_get_device_rev(struct se_device *dev)
521{
522 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
523}
524
525/* fd_get_device_type(): (Part of se_subsystem_api_t template)
526 *
527 *
528 */
529static u32 fd_get_device_type(struct se_device *dev)
530{
531 return TYPE_DISK;
532}
533
534static sector_t fd_get_blocks(struct se_device *dev)
535{
536 struct fd_dev *fd_dev = dev->dev_ptr;
537 struct file *f = fd_dev->fd_file;
538 struct inode *i = f->f_mapping->host;
539 unsigned long long dev_size;
540 /*
541 * When using a file that references an underlying struct block_device,
542 * ensure dev_size is always based on the current inode size in order
543 * to handle underlying block_device resize operations.
544 */
545 if (S_ISBLK(i->i_mode))
546 dev_size = (i_size_read(i) - fd_dev->fd_block_size);
547 else
548 dev_size = fd_dev->fd_dev_size;
549
550 return div_u64(dev_size, dev->se_sub_dev->se_dev_attrib.block_size);
551}
552
553static struct se_subsystem_api fileio_template = {
554 .name = "fileio",
555 .owner = THIS_MODULE,
556 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
557 .write_cache_emulated = 1,
558 .fua_write_emulated = 1,
559 .attach_hba = fd_attach_hba,
560 .detach_hba = fd_detach_hba,
561 .allocate_virtdevice = fd_allocate_virtdevice,
562 .create_virtdevice = fd_create_virtdevice,
563 .free_device = fd_free_device,
564 .execute_cmd = fd_execute_cmd,
565 .do_sync_cache = fd_emulate_sync_cache,
566 .check_configfs_dev_params = fd_check_configfs_dev_params,
567 .set_configfs_dev_params = fd_set_configfs_dev_params,
568 .show_configfs_dev_params = fd_show_configfs_dev_params,
569 .get_device_rev = fd_get_device_rev,
570 .get_device_type = fd_get_device_type,
571 .get_blocks = fd_get_blocks,
572};
573
574static int __init fileio_module_init(void)
575{
576 return transport_subsystem_register(&fileio_template);
577}
578
579static void fileio_module_exit(void)
580{
581 transport_subsystem_release(&fileio_template);
582}
583
584MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
585MODULE_AUTHOR("nab@Linux-iSCSI.org");
586MODULE_LICENSE("GPL");
587
588module_init(fileio_module_init);
589module_exit(fileio_module_exit);