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
FD_DEV(struct se_device * dev)32 static inline struct fd_dev *FD_DEV(struct se_device *dev)
33 {
34 return container_of(dev, struct fd_dev, dev);
35 }
36
fd_attach_hba(struct se_hba * hba,u32 host_id)37 static 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
fd_detach_hba(struct se_hba * hba)60 static 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
fd_alloc_device(struct se_hba * hba,const char * name)71 static 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
fd_configure_unmap(struct se_device * dev)89 static 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
fd_configure_device(struct se_device * dev)107 static 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;
213 fail:
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
fd_dev_call_rcu(struct rcu_head * p)221 static 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
fd_free_device(struct se_device * dev)229 static void fd_free_device(struct se_device *dev)
230 {
231 call_rcu(&dev->rcu_head, fd_dev_call_rcu);
232 }
233
fd_destroy_device(struct se_device * dev)234 static 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
244 struct target_core_file_cmd {
245 unsigned long len;
246 struct se_cmd *cmd;
247 struct kiocb iocb;
248 struct bio_vec bvecs[];
249 };
250
cmd_rw_aio_complete(struct kiocb * iocb,long ret)251 static 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
265 static sense_reason_t
fd_execute_rw_aio(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)266 fd_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
fd_do_rw(struct se_cmd * cmd,struct file * fd,u32 block_size,struct scatterlist * sgl,u32 sgl_nents,u32 data_length,int is_write)312 static 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 file_start_write(fd);
337 ret = vfs_iter_write(fd, &iter, &pos, 0);
338 file_end_write(fd);
339 } else {
340 ret = vfs_iter_read(fd, &iter, &pos, 0);
341 }
342 if (is_write) {
343 if (ret < 0 || ret != data_length) {
344 pr_err("%s() write returned %d\n", __func__, ret);
345 if (ret >= 0)
346 ret = -EINVAL;
347 }
348 } else {
349 /*
350 * Return zeros and GOOD status even if the READ did not return
351 * the expected virt_size for struct file w/o a backing struct
352 * block_device.
353 */
354 if (S_ISBLK(file_inode(fd)->i_mode)) {
355 if (ret < 0 || ret != data_length) {
356 pr_err("%s() returned %d, expecting %u for "
357 "S_ISBLK\n", __func__, ret,
358 data_length);
359 if (ret >= 0)
360 ret = -EINVAL;
361 }
362 } else {
363 if (ret < 0) {
364 pr_err("%s() returned %d for non S_ISBLK\n",
365 __func__, ret);
366 } else if (ret != data_length) {
367 /*
368 * Short read case:
369 * Probably some one truncate file under us.
370 * We must explicitly zero sg-pages to prevent
371 * expose uninizialized pages to userspace.
372 */
373 if (ret < data_length)
374 ret += iov_iter_zero(data_length - ret, &iter);
375 else
376 ret = -EINVAL;
377 }
378 }
379 }
380 kfree(bvec);
381 return ret;
382 }
383
384 static sense_reason_t
fd_execute_sync_cache(struct se_cmd * cmd)385 fd_execute_sync_cache(struct se_cmd *cmd)
386 {
387 struct se_device *dev = cmd->se_dev;
388 struct fd_dev *fd_dev = FD_DEV(dev);
389 int immed = (cmd->t_task_cdb[1] & 0x2);
390 loff_t start, end;
391 int ret;
392
393 /*
394 * If the Immediate bit is set, queue up the GOOD response
395 * for this SYNCHRONIZE_CACHE op
396 */
397 if (immed)
398 target_complete_cmd(cmd, SAM_STAT_GOOD);
399
400 /*
401 * Determine if we will be flushing the entire device.
402 */
403 if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
404 start = 0;
405 end = LLONG_MAX;
406 } else {
407 start = cmd->t_task_lba * dev->dev_attrib.block_size;
408 if (cmd->data_length)
409 end = start + cmd->data_length - 1;
410 else
411 end = LLONG_MAX;
412 }
413
414 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
415 if (ret != 0)
416 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
417
418 if (immed)
419 return 0;
420
421 if (ret)
422 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
423 else
424 target_complete_cmd(cmd, SAM_STAT_GOOD);
425
426 return 0;
427 }
428
429 static sense_reason_t
fd_execute_write_same(struct se_cmd * cmd)430 fd_execute_write_same(struct se_cmd *cmd)
431 {
432 struct se_device *se_dev = cmd->se_dev;
433 struct fd_dev *fd_dev = FD_DEV(se_dev);
434 loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
435 sector_t nolb = sbc_get_write_same_sectors(cmd);
436 struct iov_iter iter;
437 struct bio_vec *bvec;
438 unsigned int len = 0, i;
439 ssize_t ret;
440
441 if (cmd->prot_op) {
442 pr_err("WRITE_SAME: Protection information with FILEIO"
443 " backends not supported\n");
444 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
445 }
446
447 if (!cmd->t_data_nents)
448 return TCM_INVALID_CDB_FIELD;
449
450 if (cmd->t_data_nents > 1 ||
451 cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
452 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
453 " block_size: %u\n",
454 cmd->t_data_nents,
455 cmd->t_data_sg[0].length,
456 cmd->se_dev->dev_attrib.block_size);
457 return TCM_INVALID_CDB_FIELD;
458 }
459
460 bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
461 if (!bvec)
462 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
463
464 for (i = 0; i < nolb; i++) {
465 bvec_set_page(&bvec[i], sg_page(&cmd->t_data_sg[0]),
466 cmd->t_data_sg[0].length,
467 cmd->t_data_sg[0].offset);
468 len += se_dev->dev_attrib.block_size;
469 }
470
471 iov_iter_bvec(&iter, ITER_SOURCE, bvec, nolb, len);
472 file_start_write(fd_dev->fd_file);
473 ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0);
474 file_end_write(fd_dev->fd_file);
475
476 kfree(bvec);
477 if (ret < 0 || ret != len) {
478 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
479 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
480 }
481
482 target_complete_cmd(cmd, SAM_STAT_GOOD);
483 return 0;
484 }
485
486 static int
fd_do_prot_fill(struct se_device * se_dev,sector_t lba,sector_t nolb,void * buf,size_t bufsize)487 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
488 void *buf, size_t bufsize)
489 {
490 struct fd_dev *fd_dev = FD_DEV(se_dev);
491 struct file *prot_fd = fd_dev->fd_prot_file;
492 sector_t prot_length, prot;
493 loff_t pos = lba * se_dev->prot_length;
494
495 if (!prot_fd) {
496 pr_err("Unable to locate fd_dev->fd_prot_file\n");
497 return -ENODEV;
498 }
499
500 prot_length = nolb * se_dev->prot_length;
501
502 memset(buf, 0xff, bufsize);
503 for (prot = 0; prot < prot_length;) {
504 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
505 ssize_t ret = kernel_write(prot_fd, buf, len, &pos);
506
507 if (ret != len) {
508 pr_err("vfs_write to prot file failed: %zd\n", ret);
509 return ret < 0 ? ret : -ENODEV;
510 }
511 prot += ret;
512 }
513
514 return 0;
515 }
516
517 static int
fd_do_prot_unmap(struct se_cmd * cmd,sector_t lba,sector_t nolb)518 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
519 {
520 void *buf;
521 int rc;
522
523 buf = (void *)__get_free_page(GFP_KERNEL);
524 if (!buf) {
525 pr_err("Unable to allocate FILEIO prot buf\n");
526 return -ENOMEM;
527 }
528
529 rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
530
531 free_page((unsigned long)buf);
532
533 return rc;
534 }
535
536 static sense_reason_t
fd_execute_unmap(struct se_cmd * cmd,sector_t lba,sector_t nolb)537 fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
538 {
539 struct file *file = FD_DEV(cmd->se_dev)->fd_file;
540 struct inode *inode = file->f_mapping->host;
541 int ret;
542
543 if (!nolb) {
544 return 0;
545 }
546
547 if (cmd->se_dev->dev_attrib.pi_prot_type) {
548 ret = fd_do_prot_unmap(cmd, lba, nolb);
549 if (ret)
550 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
551 }
552
553 if (S_ISBLK(inode->i_mode)) {
554 /* The backend is block device, use discard */
555 struct block_device *bdev = I_BDEV(inode);
556 struct se_device *dev = cmd->se_dev;
557
558 ret = blkdev_issue_discard(bdev,
559 target_to_linux_sector(dev, lba),
560 target_to_linux_sector(dev, nolb),
561 GFP_KERNEL);
562 if (ret < 0) {
563 pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
564 ret);
565 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
566 }
567 } else {
568 /* The backend is normal file, use fallocate */
569 struct se_device *se_dev = cmd->se_dev;
570 loff_t pos = lba * se_dev->dev_attrib.block_size;
571 unsigned int len = nolb * se_dev->dev_attrib.block_size;
572 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
573
574 if (!file->f_op->fallocate)
575 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
576
577 ret = file->f_op->fallocate(file, mode, pos, len);
578 if (ret < 0) {
579 pr_warn("FILEIO: fallocate() failed: %d\n", ret);
580 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
581 }
582 }
583
584 return 0;
585 }
586
587 static sense_reason_t
fd_execute_rw_buffered(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)588 fd_execute_rw_buffered(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
589 enum dma_data_direction data_direction)
590 {
591 struct se_device *dev = cmd->se_dev;
592 struct fd_dev *fd_dev = FD_DEV(dev);
593 struct file *file = fd_dev->fd_file;
594 struct file *pfile = fd_dev->fd_prot_file;
595 sense_reason_t rc;
596 int ret = 0;
597 /*
598 * Call vectorized fileio functions to map struct scatterlist
599 * physical memory addresses to struct iovec virtual memory.
600 */
601 if (data_direction == DMA_FROM_DEVICE) {
602 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
603 ret = fd_do_rw(cmd, pfile, dev->prot_length,
604 cmd->t_prot_sg, cmd->t_prot_nents,
605 cmd->prot_length, 0);
606 if (ret < 0)
607 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
608 }
609
610 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
611 sgl, sgl_nents, cmd->data_length, 0);
612
613 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type &&
614 dev->dev_attrib.pi_prot_verify) {
615 u32 sectors = cmd->data_length >>
616 ilog2(dev->dev_attrib.block_size);
617
618 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
619 0, cmd->t_prot_sg, 0);
620 if (rc)
621 return rc;
622 }
623 } else {
624 if (cmd->prot_type && dev->dev_attrib.pi_prot_type &&
625 dev->dev_attrib.pi_prot_verify) {
626 u32 sectors = cmd->data_length >>
627 ilog2(dev->dev_attrib.block_size);
628
629 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
630 0, cmd->t_prot_sg, 0);
631 if (rc)
632 return rc;
633 }
634
635 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
636 sgl, sgl_nents, cmd->data_length, 1);
637 /*
638 * Perform implicit vfs_fsync_range() for fd_do_writev() ops
639 * for SCSI WRITEs with Forced Unit Access (FUA) set.
640 * Allow this to happen independent of WCE=0 setting.
641 */
642 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
643 loff_t start = cmd->t_task_lba *
644 dev->dev_attrib.block_size;
645 loff_t end;
646
647 if (cmd->data_length)
648 end = start + cmd->data_length - 1;
649 else
650 end = LLONG_MAX;
651
652 vfs_fsync_range(fd_dev->fd_file, start, end, 1);
653 }
654
655 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
656 ret = fd_do_rw(cmd, pfile, dev->prot_length,
657 cmd->t_prot_sg, cmd->t_prot_nents,
658 cmd->prot_length, 1);
659 if (ret < 0)
660 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
661 }
662 }
663
664 if (ret < 0)
665 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
666
667 target_complete_cmd(cmd, SAM_STAT_GOOD);
668 return 0;
669 }
670
671 static sense_reason_t
fd_execute_rw(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)672 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
673 enum dma_data_direction data_direction)
674 {
675 struct se_device *dev = cmd->se_dev;
676 struct fd_dev *fd_dev = FD_DEV(dev);
677
678 /*
679 * We are currently limited by the number of iovecs (2048) per
680 * single vfs_[writev,readv] call.
681 */
682 if (cmd->data_length > FD_MAX_BYTES) {
683 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
684 "FD_MAX_BYTES: %u iovec count limitation\n",
685 cmd->data_length, FD_MAX_BYTES);
686 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
687 }
688
689 if (fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO)
690 return fd_execute_rw_aio(cmd, sgl, sgl_nents, data_direction);
691 return fd_execute_rw_buffered(cmd, sgl, sgl_nents, data_direction);
692 }
693
694 enum {
695 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io,
696 Opt_fd_async_io, Opt_err
697 };
698
699 static match_table_t tokens = {
700 {Opt_fd_dev_name, "fd_dev_name=%s"},
701 {Opt_fd_dev_size, "fd_dev_size=%s"},
702 {Opt_fd_buffered_io, "fd_buffered_io=%d"},
703 {Opt_fd_async_io, "fd_async_io=%d"},
704 {Opt_err, NULL}
705 };
706
fd_set_configfs_dev_params(struct se_device * dev,const char * page,ssize_t count)707 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
708 const char *page, ssize_t count)
709 {
710 struct fd_dev *fd_dev = FD_DEV(dev);
711 char *orig, *ptr, *arg_p, *opts;
712 substring_t args[MAX_OPT_ARGS];
713 int ret = 0, arg, token;
714
715 opts = kstrdup(page, GFP_KERNEL);
716 if (!opts)
717 return -ENOMEM;
718
719 orig = opts;
720
721 while ((ptr = strsep(&opts, ",\n")) != NULL) {
722 if (!*ptr)
723 continue;
724
725 token = match_token(ptr, tokens, args);
726 switch (token) {
727 case Opt_fd_dev_name:
728 if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
729 FD_MAX_DEV_NAME) == 0) {
730 ret = -EINVAL;
731 break;
732 }
733 pr_debug("FILEIO: Referencing Path: %s\n",
734 fd_dev->fd_dev_name);
735 fd_dev->fbd_flags |= FBDF_HAS_PATH;
736 break;
737 case Opt_fd_dev_size:
738 arg_p = match_strdup(&args[0]);
739 if (!arg_p) {
740 ret = -ENOMEM;
741 break;
742 }
743 ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
744 kfree(arg_p);
745 if (ret < 0) {
746 pr_err("kstrtoull() failed for"
747 " fd_dev_size=\n");
748 goto out;
749 }
750 pr_debug("FILEIO: Referencing Size: %llu"
751 " bytes\n", fd_dev->fd_dev_size);
752 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
753 break;
754 case Opt_fd_buffered_io:
755 ret = match_int(args, &arg);
756 if (ret)
757 goto out;
758 if (arg != 1) {
759 pr_err("bogus fd_buffered_io=%d value\n", arg);
760 ret = -EINVAL;
761 goto out;
762 }
763
764 pr_debug("FILEIO: Using buffered I/O"
765 " operations for struct fd_dev\n");
766
767 fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
768 break;
769 case Opt_fd_async_io:
770 ret = match_int(args, &arg);
771 if (ret)
772 goto out;
773 if (arg != 1) {
774 pr_err("bogus fd_async_io=%d value\n", arg);
775 ret = -EINVAL;
776 goto out;
777 }
778
779 pr_debug("FILEIO: Using async I/O"
780 " operations for struct fd_dev\n");
781
782 fd_dev->fbd_flags |= FDBD_HAS_ASYNC_IO;
783 break;
784 default:
785 break;
786 }
787 }
788
789 out:
790 kfree(orig);
791 return (!ret) ? count : ret;
792 }
793
fd_show_configfs_dev_params(struct se_device * dev,char * b)794 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
795 {
796 struct fd_dev *fd_dev = FD_DEV(dev);
797 ssize_t bl = 0;
798
799 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
800 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s Async: %d\n",
801 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
802 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
803 "Buffered-WCE" : "O_DSYNC",
804 !!(fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO));
805 return bl;
806 }
807
fd_get_blocks(struct se_device * dev)808 static sector_t fd_get_blocks(struct se_device *dev)
809 {
810 struct fd_dev *fd_dev = FD_DEV(dev);
811 struct file *f = fd_dev->fd_file;
812 struct inode *i = f->f_mapping->host;
813 unsigned long long dev_size;
814 /*
815 * When using a file that references an underlying struct block_device,
816 * ensure dev_size is always based on the current inode size in order
817 * to handle underlying block_device resize operations.
818 */
819 if (S_ISBLK(i->i_mode))
820 dev_size = i_size_read(i);
821 else
822 dev_size = fd_dev->fd_dev_size;
823
824 return div_u64(dev_size - dev->dev_attrib.block_size,
825 dev->dev_attrib.block_size);
826 }
827
fd_init_prot(struct se_device * dev)828 static int fd_init_prot(struct se_device *dev)
829 {
830 struct fd_dev *fd_dev = FD_DEV(dev);
831 struct file *prot_file, *file = fd_dev->fd_file;
832 struct inode *inode;
833 int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
834 char buf[FD_MAX_DEV_PROT_NAME];
835
836 if (!file) {
837 pr_err("Unable to locate fd_dev->fd_file\n");
838 return -ENODEV;
839 }
840
841 inode = file->f_mapping->host;
842 if (S_ISBLK(inode->i_mode)) {
843 pr_err("FILEIO Protection emulation only supported on"
844 " !S_ISBLK\n");
845 return -ENOSYS;
846 }
847
848 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
849 flags &= ~O_DSYNC;
850
851 snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
852 fd_dev->fd_dev_name);
853
854 prot_file = filp_open(buf, flags, 0600);
855 if (IS_ERR(prot_file)) {
856 pr_err("filp_open(%s) failed\n", buf);
857 ret = PTR_ERR(prot_file);
858 return ret;
859 }
860 fd_dev->fd_prot_file = prot_file;
861
862 return 0;
863 }
864
fd_format_prot(struct se_device * dev)865 static int fd_format_prot(struct se_device *dev)
866 {
867 unsigned char *buf;
868 int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
869 int ret;
870
871 if (!dev->dev_attrib.pi_prot_type) {
872 pr_err("Unable to format_prot while pi_prot_type == 0\n");
873 return -ENODEV;
874 }
875
876 buf = vzalloc(unit_size);
877 if (!buf) {
878 pr_err("Unable to allocate FILEIO prot buf\n");
879 return -ENOMEM;
880 }
881
882 pr_debug("Using FILEIO prot_length: %llu\n",
883 (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
884 dev->prot_length);
885
886 ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
887 buf, unit_size);
888 vfree(buf);
889 return ret;
890 }
891
fd_free_prot(struct se_device * dev)892 static void fd_free_prot(struct se_device *dev)
893 {
894 struct fd_dev *fd_dev = FD_DEV(dev);
895
896 if (!fd_dev->fd_prot_file)
897 return;
898
899 filp_close(fd_dev->fd_prot_file, NULL);
900 fd_dev->fd_prot_file = NULL;
901 }
902
903 static struct exec_cmd_ops fd_exec_cmd_ops = {
904 .execute_rw = fd_execute_rw,
905 .execute_sync_cache = fd_execute_sync_cache,
906 .execute_write_same = fd_execute_write_same,
907 .execute_unmap = fd_execute_unmap,
908 };
909
910 static sense_reason_t
fd_parse_cdb(struct se_cmd * cmd)911 fd_parse_cdb(struct se_cmd *cmd)
912 {
913 return sbc_parse_cdb(cmd, &fd_exec_cmd_ops);
914 }
915
916 static const struct target_backend_ops fileio_ops = {
917 .name = "fileio",
918 .inquiry_prod = "FILEIO",
919 .inquiry_rev = FD_VERSION,
920 .owner = THIS_MODULE,
921 .attach_hba = fd_attach_hba,
922 .detach_hba = fd_detach_hba,
923 .alloc_device = fd_alloc_device,
924 .configure_device = fd_configure_device,
925 .destroy_device = fd_destroy_device,
926 .free_device = fd_free_device,
927 .configure_unmap = fd_configure_unmap,
928 .parse_cdb = fd_parse_cdb,
929 .set_configfs_dev_params = fd_set_configfs_dev_params,
930 .show_configfs_dev_params = fd_show_configfs_dev_params,
931 .get_device_type = sbc_get_device_type,
932 .get_blocks = fd_get_blocks,
933 .init_prot = fd_init_prot,
934 .format_prot = fd_format_prot,
935 .free_prot = fd_free_prot,
936 .tb_dev_attrib_attrs = sbc_attrib_attrs,
937 };
938
fileio_module_init(void)939 static int __init fileio_module_init(void)
940 {
941 return transport_backend_register(&fileio_ops);
942 }
943
fileio_module_exit(void)944 static void __exit fileio_module_exit(void)
945 {
946 target_backend_unregister(&fileio_ops);
947 }
948
949 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
950 MODULE_AUTHOR("nab@Linux-iSCSI.org");
951 MODULE_LICENSE("GPL");
952
953 module_init(fileio_module_init);
954 module_exit(fileio_module_exit);
955