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 <scsi/scsi_proto.h>
24 #include <asm/unaligned.h>
25
26 #include <target/target_core_base.h>
27 #include <target/target_core_backend.h>
28
29 #include "target_core_file.h"
30
FD_DEV(struct se_device * dev)31 static inline struct fd_dev *FD_DEV(struct se_device *dev)
32 {
33 return container_of(dev, struct fd_dev, dev);
34 }
35
fd_attach_hba(struct se_hba * hba,u32 host_id)36 static int fd_attach_hba(struct se_hba *hba, u32 host_id)
37 {
38 struct fd_host *fd_host;
39
40 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
41 if (!fd_host) {
42 pr_err("Unable to allocate memory for struct fd_host\n");
43 return -ENOMEM;
44 }
45
46 fd_host->fd_host_id = host_id;
47
48 hba->hba_ptr = fd_host;
49
50 pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
51 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
52 TARGET_CORE_VERSION);
53 pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n",
54 hba->hba_id, fd_host->fd_host_id);
55
56 return 0;
57 }
58
fd_detach_hba(struct se_hba * hba)59 static void fd_detach_hba(struct se_hba *hba)
60 {
61 struct fd_host *fd_host = hba->hba_ptr;
62
63 pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
64 " Target Core\n", hba->hba_id, fd_host->fd_host_id);
65
66 kfree(fd_host);
67 hba->hba_ptr = NULL;
68 }
69
fd_alloc_device(struct se_hba * hba,const char * name)70 static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name)
71 {
72 struct fd_dev *fd_dev;
73 struct fd_host *fd_host = hba->hba_ptr;
74
75 fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
76 if (!fd_dev) {
77 pr_err("Unable to allocate memory for struct fd_dev\n");
78 return NULL;
79 }
80
81 fd_dev->fd_host = fd_host;
82
83 pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
84
85 return &fd_dev->dev;
86 }
87
fd_configure_device(struct se_device * dev)88 static int fd_configure_device(struct se_device *dev)
89 {
90 struct fd_dev *fd_dev = FD_DEV(dev);
91 struct fd_host *fd_host = dev->se_hba->hba_ptr;
92 struct file *file;
93 struct inode *inode = NULL;
94 int flags, ret = -EINVAL;
95
96 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
97 pr_err("Missing fd_dev_name=\n");
98 return -EINVAL;
99 }
100
101 /*
102 * Use O_DSYNC by default instead of O_SYNC to forgo syncing
103 * of pure timestamp updates.
104 */
105 flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
106
107 /*
108 * Optionally allow fd_buffered_io=1 to be enabled for people
109 * who want use the fs buffer cache as an WriteCache mechanism.
110 *
111 * This means that in event of a hard failure, there is a risk
112 * of silent data-loss if the SCSI client has *not* performed a
113 * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
114 * to write-out the entire device cache.
115 */
116 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
117 pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
118 flags &= ~O_DSYNC;
119 }
120
121 file = filp_open(fd_dev->fd_dev_name, flags, 0600);
122 if (IS_ERR(file)) {
123 pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
124 ret = PTR_ERR(file);
125 goto fail;
126 }
127 fd_dev->fd_file = file;
128 /*
129 * If using a block backend with this struct file, we extract
130 * fd_dev->fd_[block,dev]_size from struct block_device.
131 *
132 * Otherwise, we use the passed fd_size= from configfs
133 */
134 inode = file->f_mapping->host;
135 if (S_ISBLK(inode->i_mode)) {
136 struct request_queue *q = bdev_get_queue(I_BDEV(inode));
137 unsigned long long dev_size;
138
139 fd_dev->fd_block_size = bdev_logical_block_size(I_BDEV(inode));
140 /*
141 * Determine the number of bytes from i_size_read() minus
142 * one (1) logical sector from underlying struct block_device
143 */
144 dev_size = (i_size_read(file->f_mapping->host) -
145 fd_dev->fd_block_size);
146
147 pr_debug("FILEIO: Using size: %llu bytes from struct"
148 " block_device blocks: %llu logical_block_size: %d\n",
149 dev_size, div_u64(dev_size, fd_dev->fd_block_size),
150 fd_dev->fd_block_size);
151
152 if (target_configure_unmap_from_queue(&dev->dev_attrib, q))
153 pr_debug("IFILE: BLOCK Discard support available,"
154 " disabled by default\n");
155 /*
156 * Enable write same emulation for IBLOCK and use 0xFFFF as
157 * the smaller WRITE_SAME(10) only has a two-byte block count.
158 */
159 dev->dev_attrib.max_write_same_len = 0xFFFF;
160
161 if (blk_queue_nonrot(q))
162 dev->dev_attrib.is_nonrot = 1;
163 } else {
164 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
165 pr_err("FILEIO: Missing fd_dev_size="
166 " parameter, and no backing struct"
167 " block_device\n");
168 goto fail;
169 }
170
171 fd_dev->fd_block_size = FD_BLOCKSIZE;
172 /*
173 * Limit UNMAP emulation to 8k Number of LBAs (NoLB)
174 */
175 dev->dev_attrib.max_unmap_lba_count = 0x2000;
176 /*
177 * Currently hardcoded to 1 in Linux/SCSI code..
178 */
179 dev->dev_attrib.max_unmap_block_desc_count = 1;
180 dev->dev_attrib.unmap_granularity = 1;
181 dev->dev_attrib.unmap_granularity_alignment = 0;
182
183 /*
184 * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
185 * based upon struct iovec limit for vfs_writev()
186 */
187 dev->dev_attrib.max_write_same_len = 0x1000;
188 }
189
190 dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
191 dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES;
192 dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
193 dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
194
195 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
196 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
197 " with FDBD_HAS_BUFFERED_IO_WCE\n");
198 dev->dev_attrib.emulate_write_cache = 1;
199 }
200
201 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
202 fd_dev->fd_queue_depth = dev->queue_depth;
203
204 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
205 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
206 fd_dev->fd_dev_name, fd_dev->fd_dev_size);
207
208 return 0;
209 fail:
210 if (fd_dev->fd_file) {
211 filp_close(fd_dev->fd_file, NULL);
212 fd_dev->fd_file = NULL;
213 }
214 return ret;
215 }
216
fd_dev_call_rcu(struct rcu_head * p)217 static void fd_dev_call_rcu(struct rcu_head *p)
218 {
219 struct se_device *dev = container_of(p, struct se_device, rcu_head);
220 struct fd_dev *fd_dev = FD_DEV(dev);
221
222 kfree(fd_dev);
223 }
224
fd_free_device(struct se_device * dev)225 static void fd_free_device(struct se_device *dev)
226 {
227 call_rcu(&dev->rcu_head, fd_dev_call_rcu);
228 }
229
fd_destroy_device(struct se_device * dev)230 static void fd_destroy_device(struct se_device *dev)
231 {
232 struct fd_dev *fd_dev = FD_DEV(dev);
233
234 if (fd_dev->fd_file) {
235 filp_close(fd_dev->fd_file, NULL);
236 fd_dev->fd_file = NULL;
237 }
238 }
239
240 struct target_core_file_cmd {
241 unsigned long len;
242 struct se_cmd *cmd;
243 struct kiocb iocb;
244 struct bio_vec bvecs[];
245 };
246
cmd_rw_aio_complete(struct kiocb * iocb,long ret,long ret2)247 static void cmd_rw_aio_complete(struct kiocb *iocb, long ret, long ret2)
248 {
249 struct target_core_file_cmd *cmd;
250
251 cmd = container_of(iocb, struct target_core_file_cmd, iocb);
252
253 if (ret != cmd->len)
254 target_complete_cmd(cmd->cmd, SAM_STAT_CHECK_CONDITION);
255 else
256 target_complete_cmd(cmd->cmd, SAM_STAT_GOOD);
257
258 kfree(cmd);
259 }
260
261 static sense_reason_t
fd_execute_rw_aio(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)262 fd_execute_rw_aio(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
263 enum dma_data_direction data_direction)
264 {
265 int is_write = !(data_direction == DMA_FROM_DEVICE);
266 struct se_device *dev = cmd->se_dev;
267 struct fd_dev *fd_dev = FD_DEV(dev);
268 struct file *file = fd_dev->fd_file;
269 struct target_core_file_cmd *aio_cmd;
270 struct iov_iter iter;
271 struct scatterlist *sg;
272 ssize_t len = 0;
273 int ret = 0, i;
274
275 aio_cmd = kmalloc(struct_size(aio_cmd, bvecs, sgl_nents), GFP_KERNEL);
276 if (!aio_cmd)
277 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
278
279 for_each_sg(sgl, sg, sgl_nents, i) {
280 aio_cmd->bvecs[i].bv_page = sg_page(sg);
281 aio_cmd->bvecs[i].bv_len = sg->length;
282 aio_cmd->bvecs[i].bv_offset = sg->offset;
283
284 len += sg->length;
285 }
286
287 iov_iter_bvec(&iter, is_write, aio_cmd->bvecs, sgl_nents, len);
288
289 aio_cmd->cmd = cmd;
290 aio_cmd->len = len;
291 aio_cmd->iocb.ki_pos = cmd->t_task_lba * dev->dev_attrib.block_size;
292 aio_cmd->iocb.ki_filp = file;
293 aio_cmd->iocb.ki_complete = cmd_rw_aio_complete;
294 aio_cmd->iocb.ki_flags = IOCB_DIRECT;
295
296 if (is_write && (cmd->se_cmd_flags & SCF_FUA))
297 aio_cmd->iocb.ki_flags |= IOCB_DSYNC;
298
299 if (is_write)
300 ret = call_write_iter(file, &aio_cmd->iocb, &iter);
301 else
302 ret = call_read_iter(file, &aio_cmd->iocb, &iter);
303
304 if (ret != -EIOCBQUEUED)
305 cmd_rw_aio_complete(&aio_cmd->iocb, ret, 0);
306
307 return 0;
308 }
309
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)310 static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
311 u32 block_size, struct scatterlist *sgl,
312 u32 sgl_nents, u32 data_length, int is_write)
313 {
314 struct scatterlist *sg;
315 struct iov_iter iter;
316 struct bio_vec *bvec;
317 ssize_t len = 0;
318 loff_t pos = (cmd->t_task_lba * block_size);
319 int ret = 0, i;
320
321 bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
322 if (!bvec) {
323 pr_err("Unable to allocate fd_do_readv iov[]\n");
324 return -ENOMEM;
325 }
326
327 for_each_sg(sgl, sg, sgl_nents, i) {
328 bvec[i].bv_page = sg_page(sg);
329 bvec[i].bv_len = sg->length;
330 bvec[i].bv_offset = sg->offset;
331
332 len += sg->length;
333 }
334
335 iov_iter_bvec(&iter, READ, bvec, sgl_nents, len);
336 if (is_write)
337 ret = vfs_iter_write(fd, &iter, &pos, 0);
338 else
339 ret = vfs_iter_read(fd, &iter, &pos, 0);
340
341 if (is_write) {
342 if (ret < 0 || ret != data_length) {
343 pr_err("%s() write returned %d\n", __func__, ret);
344 if (ret >= 0)
345 ret = -EINVAL;
346 }
347 } else {
348 /*
349 * Return zeros and GOOD status even if the READ did not return
350 * the expected virt_size for struct file w/o a backing struct
351 * block_device.
352 */
353 if (S_ISBLK(file_inode(fd)->i_mode)) {
354 if (ret < 0 || ret != data_length) {
355 pr_err("%s() returned %d, expecting %u for "
356 "S_ISBLK\n", __func__, ret,
357 data_length);
358 if (ret >= 0)
359 ret = -EINVAL;
360 }
361 } else {
362 if (ret < 0) {
363 pr_err("%s() returned %d for non S_ISBLK\n",
364 __func__, ret);
365 } else if (ret != data_length) {
366 /*
367 * Short read case:
368 * Probably some one truncate file under us.
369 * We must explicitly zero sg-pages to prevent
370 * expose uninizialized pages to userspace.
371 */
372 if (ret < data_length)
373 ret += iov_iter_zero(data_length - ret, &iter);
374 else
375 ret = -EINVAL;
376 }
377 }
378 }
379 kfree(bvec);
380 return ret;
381 }
382
383 static sense_reason_t
fd_execute_sync_cache(struct se_cmd * cmd)384 fd_execute_sync_cache(struct se_cmd *cmd)
385 {
386 struct se_device *dev = cmd->se_dev;
387 struct fd_dev *fd_dev = FD_DEV(dev);
388 int immed = (cmd->t_task_cdb[1] & 0x2);
389 loff_t start, end;
390 int ret;
391
392 /*
393 * If the Immediate bit is set, queue up the GOOD response
394 * for this SYNCHRONIZE_CACHE op
395 */
396 if (immed)
397 target_complete_cmd(cmd, SAM_STAT_GOOD);
398
399 /*
400 * Determine if we will be flushing the entire device.
401 */
402 if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
403 start = 0;
404 end = LLONG_MAX;
405 } else {
406 start = cmd->t_task_lba * dev->dev_attrib.block_size;
407 if (cmd->data_length)
408 end = start + cmd->data_length - 1;
409 else
410 end = LLONG_MAX;
411 }
412
413 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
414 if (ret != 0)
415 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
416
417 if (immed)
418 return 0;
419
420 if (ret)
421 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
422 else
423 target_complete_cmd(cmd, SAM_STAT_GOOD);
424
425 return 0;
426 }
427
428 static sense_reason_t
fd_execute_write_same(struct se_cmd * cmd)429 fd_execute_write_same(struct se_cmd *cmd)
430 {
431 struct se_device *se_dev = cmd->se_dev;
432 struct fd_dev *fd_dev = FD_DEV(se_dev);
433 loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
434 sector_t nolb = sbc_get_write_same_sectors(cmd);
435 struct iov_iter iter;
436 struct bio_vec *bvec;
437 unsigned int len = 0, i;
438 ssize_t ret;
439
440 if (!nolb) {
441 target_complete_cmd(cmd, SAM_STAT_GOOD);
442 return 0;
443 }
444 if (cmd->prot_op) {
445 pr_err("WRITE_SAME: Protection information with FILEIO"
446 " backends not supported\n");
447 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
448 }
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[i].bv_page = sg_page(&cmd->t_data_sg[0]);
466 bvec[i].bv_len = cmd->t_data_sg[0].length;
467 bvec[i].bv_offset = cmd->t_data_sg[0].offset;
468
469 len += se_dev->dev_attrib.block_size;
470 }
471
472 iov_iter_bvec(&iter, READ, bvec, nolb, len);
473 ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0);
474
475 kfree(bvec);
476 if (ret < 0 || ret != len) {
477 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
478 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
479 }
480
481 target_complete_cmd(cmd, SAM_STAT_GOOD);
482 return 0;
483 }
484
485 static int
fd_do_prot_fill(struct se_device * se_dev,sector_t lba,sector_t nolb,void * buf,size_t bufsize)486 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
487 void *buf, size_t bufsize)
488 {
489 struct fd_dev *fd_dev = FD_DEV(se_dev);
490 struct file *prot_fd = fd_dev->fd_prot_file;
491 sector_t prot_length, prot;
492 loff_t pos = lba * se_dev->prot_length;
493
494 if (!prot_fd) {
495 pr_err("Unable to locate fd_dev->fd_prot_file\n");
496 return -ENODEV;
497 }
498
499 prot_length = nolb * se_dev->prot_length;
500
501 memset(buf, 0xff, bufsize);
502 for (prot = 0; prot < prot_length;) {
503 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
504 ssize_t ret = kernel_write(prot_fd, buf, len, &pos);
505
506 if (ret != len) {
507 pr_err("vfs_write to prot file failed: %zd\n", ret);
508 return ret < 0 ? ret : -ENODEV;
509 }
510 prot += ret;
511 }
512
513 return 0;
514 }
515
516 static int
fd_do_prot_unmap(struct se_cmd * cmd,sector_t lba,sector_t nolb)517 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
518 {
519 void *buf;
520 int rc;
521
522 buf = (void *)__get_free_page(GFP_KERNEL);
523 if (!buf) {
524 pr_err("Unable to allocate FILEIO prot buf\n");
525 return -ENOMEM;
526 }
527
528 rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
529
530 free_page((unsigned long)buf);
531
532 return rc;
533 }
534
535 static sense_reason_t
fd_execute_unmap(struct se_cmd * cmd,sector_t lba,sector_t nolb)536 fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
537 {
538 struct file *file = FD_DEV(cmd->se_dev)->fd_file;
539 struct inode *inode = file->f_mapping->host;
540 int ret;
541
542 if (!nolb) {
543 return 0;
544 }
545
546 if (cmd->se_dev->dev_attrib.pi_prot_type) {
547 ret = fd_do_prot_unmap(cmd, lba, nolb);
548 if (ret)
549 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
550 }
551
552 if (S_ISBLK(inode->i_mode)) {
553 /* The backend is block device, use discard */
554 struct block_device *bdev = I_BDEV(inode);
555 struct se_device *dev = cmd->se_dev;
556
557 ret = blkdev_issue_discard(bdev,
558 target_to_linux_sector(dev, lba),
559 target_to_linux_sector(dev, nolb),
560 GFP_KERNEL, 0);
561 if (ret < 0) {
562 pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
563 ret);
564 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
565 }
566 } else {
567 /* The backend is normal file, use fallocate */
568 struct se_device *se_dev = cmd->se_dev;
569 loff_t pos = lba * se_dev->dev_attrib.block_size;
570 unsigned int len = nolb * se_dev->dev_attrib.block_size;
571 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
572
573 if (!file->f_op->fallocate)
574 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
575
576 ret = file->f_op->fallocate(file, mode, pos, len);
577 if (ret < 0) {
578 pr_warn("FILEIO: fallocate() failed: %d\n", ret);
579 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
580 }
581 }
582
583 return 0;
584 }
585
586 static sense_reason_t
fd_execute_rw_buffered(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)587 fd_execute_rw_buffered(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
588 enum dma_data_direction data_direction)
589 {
590 struct se_device *dev = cmd->se_dev;
591 struct fd_dev *fd_dev = FD_DEV(dev);
592 struct file *file = fd_dev->fd_file;
593 struct file *pfile = fd_dev->fd_prot_file;
594 sense_reason_t rc;
595 int ret = 0;
596 /*
597 * Call vectorized fileio functions to map struct scatterlist
598 * physical memory addresses to struct iovec virtual memory.
599 */
600 if (data_direction == DMA_FROM_DEVICE) {
601 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
602 ret = fd_do_rw(cmd, pfile, dev->prot_length,
603 cmd->t_prot_sg, cmd->t_prot_nents,
604 cmd->prot_length, 0);
605 if (ret < 0)
606 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
607 }
608
609 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
610 sgl, sgl_nents, cmd->data_length, 0);
611
612 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type &&
613 dev->dev_attrib.pi_prot_verify) {
614 u32 sectors = cmd->data_length >>
615 ilog2(dev->dev_attrib.block_size);
616
617 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
618 0, cmd->t_prot_sg, 0);
619 if (rc)
620 return rc;
621 }
622 } else {
623 if (cmd->prot_type && dev->dev_attrib.pi_prot_type &&
624 dev->dev_attrib.pi_prot_verify) {
625 u32 sectors = cmd->data_length >>
626 ilog2(dev->dev_attrib.block_size);
627
628 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
629 0, cmd->t_prot_sg, 0);
630 if (rc)
631 return rc;
632 }
633
634 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
635 sgl, sgl_nents, cmd->data_length, 1);
636 /*
637 * Perform implicit vfs_fsync_range() for fd_do_writev() ops
638 * for SCSI WRITEs with Forced Unit Access (FUA) set.
639 * Allow this to happen independent of WCE=0 setting.
640 */
641 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
642 loff_t start = cmd->t_task_lba *
643 dev->dev_attrib.block_size;
644 loff_t end;
645
646 if (cmd->data_length)
647 end = start + cmd->data_length - 1;
648 else
649 end = LLONG_MAX;
650
651 vfs_fsync_range(fd_dev->fd_file, start, end, 1);
652 }
653
654 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
655 ret = fd_do_rw(cmd, pfile, dev->prot_length,
656 cmd->t_prot_sg, cmd->t_prot_nents,
657 cmd->prot_length, 1);
658 if (ret < 0)
659 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
660 }
661 }
662
663 if (ret < 0)
664 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
665
666 target_complete_cmd(cmd, SAM_STAT_GOOD);
667 return 0;
668 }
669
670 static sense_reason_t
fd_execute_rw(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)671 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
672 enum dma_data_direction data_direction)
673 {
674 struct se_device *dev = cmd->se_dev;
675 struct fd_dev *fd_dev = FD_DEV(dev);
676
677 /*
678 * We are currently limited by the number of iovecs (2048) per
679 * single vfs_[writev,readv] call.
680 */
681 if (cmd->data_length > FD_MAX_BYTES) {
682 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
683 "FD_MAX_BYTES: %u iovec count limitation\n",
684 cmd->data_length, FD_MAX_BYTES);
685 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
686 }
687
688 if (fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO)
689 return fd_execute_rw_aio(cmd, sgl, sgl_nents, data_direction);
690 return fd_execute_rw_buffered(cmd, sgl, sgl_nents, data_direction);
691 }
692
693 enum {
694 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io,
695 Opt_fd_async_io, Opt_err
696 };
697
698 static match_table_t tokens = {
699 {Opt_fd_dev_name, "fd_dev_name=%s"},
700 {Opt_fd_dev_size, "fd_dev_size=%s"},
701 {Opt_fd_buffered_io, "fd_buffered_io=%d"},
702 {Opt_fd_async_io, "fd_async_io=%d"},
703 {Opt_err, NULL}
704 };
705
fd_set_configfs_dev_params(struct se_device * dev,const char * page,ssize_t count)706 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
707 const char *page, ssize_t count)
708 {
709 struct fd_dev *fd_dev = FD_DEV(dev);
710 char *orig, *ptr, *arg_p, *opts;
711 substring_t args[MAX_OPT_ARGS];
712 int ret = 0, arg, token;
713
714 opts = kstrdup(page, GFP_KERNEL);
715 if (!opts)
716 return -ENOMEM;
717
718 orig = opts;
719
720 while ((ptr = strsep(&opts, ",\n")) != NULL) {
721 if (!*ptr)
722 continue;
723
724 token = match_token(ptr, tokens, args);
725 switch (token) {
726 case Opt_fd_dev_name:
727 if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
728 FD_MAX_DEV_NAME) == 0) {
729 ret = -EINVAL;
730 break;
731 }
732 pr_debug("FILEIO: Referencing Path: %s\n",
733 fd_dev->fd_dev_name);
734 fd_dev->fbd_flags |= FBDF_HAS_PATH;
735 break;
736 case Opt_fd_dev_size:
737 arg_p = match_strdup(&args[0]);
738 if (!arg_p) {
739 ret = -ENOMEM;
740 break;
741 }
742 ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
743 kfree(arg_p);
744 if (ret < 0) {
745 pr_err("kstrtoull() failed for"
746 " fd_dev_size=\n");
747 goto out;
748 }
749 pr_debug("FILEIO: Referencing Size: %llu"
750 " bytes\n", fd_dev->fd_dev_size);
751 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
752 break;
753 case Opt_fd_buffered_io:
754 ret = match_int(args, &arg);
755 if (ret)
756 goto out;
757 if (arg != 1) {
758 pr_err("bogus fd_buffered_io=%d value\n", arg);
759 ret = -EINVAL;
760 goto out;
761 }
762
763 pr_debug("FILEIO: Using buffered I/O"
764 " operations for struct fd_dev\n");
765
766 fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
767 break;
768 case Opt_fd_async_io:
769 ret = match_int(args, &arg);
770 if (ret)
771 goto out;
772 if (arg != 1) {
773 pr_err("bogus fd_async_io=%d value\n", arg);
774 ret = -EINVAL;
775 goto out;
776 }
777
778 pr_debug("FILEIO: Using async I/O"
779 " operations for struct fd_dev\n");
780
781 fd_dev->fbd_flags |= FDBD_HAS_ASYNC_IO;
782 break;
783 default:
784 break;
785 }
786 }
787
788 out:
789 kfree(orig);
790 return (!ret) ? count : ret;
791 }
792
fd_show_configfs_dev_params(struct se_device * dev,char * b)793 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
794 {
795 struct fd_dev *fd_dev = FD_DEV(dev);
796 ssize_t bl = 0;
797
798 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
799 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s Async: %d\n",
800 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
801 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
802 "Buffered-WCE" : "O_DSYNC",
803 !!(fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO));
804 return bl;
805 }
806
fd_get_blocks(struct se_device * dev)807 static sector_t fd_get_blocks(struct se_device *dev)
808 {
809 struct fd_dev *fd_dev = FD_DEV(dev);
810 struct file *f = fd_dev->fd_file;
811 struct inode *i = f->f_mapping->host;
812 unsigned long long dev_size;
813 /*
814 * When using a file that references an underlying struct block_device,
815 * ensure dev_size is always based on the current inode size in order
816 * to handle underlying block_device resize operations.
817 */
818 if (S_ISBLK(i->i_mode))
819 dev_size = i_size_read(i);
820 else
821 dev_size = fd_dev->fd_dev_size;
822
823 return div_u64(dev_size - dev->dev_attrib.block_size,
824 dev->dev_attrib.block_size);
825 }
826
fd_init_prot(struct se_device * dev)827 static int fd_init_prot(struct se_device *dev)
828 {
829 struct fd_dev *fd_dev = FD_DEV(dev);
830 struct file *prot_file, *file = fd_dev->fd_file;
831 struct inode *inode;
832 int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
833 char buf[FD_MAX_DEV_PROT_NAME];
834
835 if (!file) {
836 pr_err("Unable to locate fd_dev->fd_file\n");
837 return -ENODEV;
838 }
839
840 inode = file->f_mapping->host;
841 if (S_ISBLK(inode->i_mode)) {
842 pr_err("FILEIO Protection emulation only supported on"
843 " !S_ISBLK\n");
844 return -ENOSYS;
845 }
846
847 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
848 flags &= ~O_DSYNC;
849
850 snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
851 fd_dev->fd_dev_name);
852
853 prot_file = filp_open(buf, flags, 0600);
854 if (IS_ERR(prot_file)) {
855 pr_err("filp_open(%s) failed\n", buf);
856 ret = PTR_ERR(prot_file);
857 return ret;
858 }
859 fd_dev->fd_prot_file = prot_file;
860
861 return 0;
862 }
863
fd_format_prot(struct se_device * dev)864 static int fd_format_prot(struct se_device *dev)
865 {
866 unsigned char *buf;
867 int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
868 int ret;
869
870 if (!dev->dev_attrib.pi_prot_type) {
871 pr_err("Unable to format_prot while pi_prot_type == 0\n");
872 return -ENODEV;
873 }
874
875 buf = vzalloc(unit_size);
876 if (!buf) {
877 pr_err("Unable to allocate FILEIO prot buf\n");
878 return -ENOMEM;
879 }
880
881 pr_debug("Using FILEIO prot_length: %llu\n",
882 (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
883 dev->prot_length);
884
885 ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
886 buf, unit_size);
887 vfree(buf);
888 return ret;
889 }
890
fd_free_prot(struct se_device * dev)891 static void fd_free_prot(struct se_device *dev)
892 {
893 struct fd_dev *fd_dev = FD_DEV(dev);
894
895 if (!fd_dev->fd_prot_file)
896 return;
897
898 filp_close(fd_dev->fd_prot_file, NULL);
899 fd_dev->fd_prot_file = NULL;
900 }
901
902 static struct sbc_ops fd_sbc_ops = {
903 .execute_rw = fd_execute_rw,
904 .execute_sync_cache = fd_execute_sync_cache,
905 .execute_write_same = fd_execute_write_same,
906 .execute_unmap = fd_execute_unmap,
907 };
908
909 static sense_reason_t
fd_parse_cdb(struct se_cmd * cmd)910 fd_parse_cdb(struct se_cmd *cmd)
911 {
912 return sbc_parse_cdb(cmd, &fd_sbc_ops);
913 }
914
915 static const struct target_backend_ops fileio_ops = {
916 .name = "fileio",
917 .inquiry_prod = "FILEIO",
918 .inquiry_rev = FD_VERSION,
919 .owner = THIS_MODULE,
920 .attach_hba = fd_attach_hba,
921 .detach_hba = fd_detach_hba,
922 .alloc_device = fd_alloc_device,
923 .configure_device = fd_configure_device,
924 .destroy_device = fd_destroy_device,
925 .free_device = fd_free_device,
926 .parse_cdb = fd_parse_cdb,
927 .set_configfs_dev_params = fd_set_configfs_dev_params,
928 .show_configfs_dev_params = fd_show_configfs_dev_params,
929 .get_device_type = sbc_get_device_type,
930 .get_blocks = fd_get_blocks,
931 .init_prot = fd_init_prot,
932 .format_prot = fd_format_prot,
933 .free_prot = fd_free_prot,
934 .tb_dev_attrib_attrs = sbc_attrib_attrs,
935 };
936
fileio_module_init(void)937 static int __init fileio_module_init(void)
938 {
939 return transport_backend_register(&fileio_ops);
940 }
941
fileio_module_exit(void)942 static void __exit fileio_module_exit(void)
943 {
944 target_backend_unregister(&fileio_ops);
945 }
946
947 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
948 MODULE_AUTHOR("nab@Linux-iSCSI.org");
949 MODULE_LICENSE("GPL");
950
951 module_init(fileio_module_init);
952 module_exit(fileio_module_exit);
953
