1 /*******************************************************************************
2 * Filename: target_core_file.c
3 *
4 * This file contains the Storage Engine <-> FILEIO transport specific functions
5 *
6 * (c) Copyright 2005-2013 Datera, Inc.
7 *
8 * Nicholas A. Bellinger <nab@kernel.org>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 *
24 ******************************************************************************/
25
26 #include <linux/string.h>
27 #include <linux/parser.h>
28 #include <linux/timer.h>
29 #include <linux/blkdev.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 #include <linux/module.h>
33 #include <linux/falloc.h>
34 #include <scsi/scsi.h>
35 #include <scsi/scsi_host.h>
36 #include <asm/unaligned.h>
37
38 #include <target/target_core_base.h>
39 #include <target/target_core_backend.h>
40
41 #include "target_core_file.h"
42
FD_DEV(struct se_device * dev)43 static inline struct fd_dev *FD_DEV(struct se_device *dev)
44 {
45 return container_of(dev, struct fd_dev, dev);
46 }
47
48 /* fd_attach_hba(): (Part of se_subsystem_api_t template)
49 *
50 *
51 */
fd_attach_hba(struct se_hba * hba,u32 host_id)52 static int fd_attach_hba(struct se_hba *hba, u32 host_id)
53 {
54 struct fd_host *fd_host;
55
56 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
57 if (!fd_host) {
58 pr_err("Unable to allocate memory for struct fd_host\n");
59 return -ENOMEM;
60 }
61
62 fd_host->fd_host_id = host_id;
63
64 hba->hba_ptr = fd_host;
65
66 pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
67 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
68 TARGET_CORE_MOD_VERSION);
69 pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n",
70 hba->hba_id, fd_host->fd_host_id);
71
72 return 0;
73 }
74
fd_detach_hba(struct se_hba * hba)75 static void fd_detach_hba(struct se_hba *hba)
76 {
77 struct fd_host *fd_host = hba->hba_ptr;
78
79 pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
80 " Target Core\n", hba->hba_id, fd_host->fd_host_id);
81
82 kfree(fd_host);
83 hba->hba_ptr = NULL;
84 }
85
fd_alloc_device(struct se_hba * hba,const char * name)86 static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name)
87 {
88 struct fd_dev *fd_dev;
89 struct fd_host *fd_host = hba->hba_ptr;
90
91 fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
92 if (!fd_dev) {
93 pr_err("Unable to allocate memory for struct fd_dev\n");
94 return NULL;
95 }
96
97 fd_dev->fd_host = fd_host;
98
99 pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
100
101 return &fd_dev->dev;
102 }
103
fd_configure_device(struct se_device * dev)104 static int fd_configure_device(struct se_device *dev)
105 {
106 struct fd_dev *fd_dev = FD_DEV(dev);
107 struct fd_host *fd_host = dev->se_hba->hba_ptr;
108 struct file *file;
109 struct inode *inode = NULL;
110 int flags, ret = -EINVAL;
111
112 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
113 pr_err("Missing fd_dev_name=\n");
114 return -EINVAL;
115 }
116
117 /*
118 * Use O_DSYNC by default instead of O_SYNC to forgo syncing
119 * of pure timestamp updates.
120 */
121 flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
122
123 /*
124 * Optionally allow fd_buffered_io=1 to be enabled for people
125 * who want use the fs buffer cache as an WriteCache mechanism.
126 *
127 * This means that in event of a hard failure, there is a risk
128 * of silent data-loss if the SCSI client has *not* performed a
129 * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
130 * to write-out the entire device cache.
131 */
132 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
133 pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
134 flags &= ~O_DSYNC;
135 }
136
137 file = filp_open(fd_dev->fd_dev_name, flags, 0600);
138 if (IS_ERR(file)) {
139 pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
140 ret = PTR_ERR(file);
141 goto fail;
142 }
143 fd_dev->fd_file = file;
144 /*
145 * If using a block backend with this struct file, we extract
146 * fd_dev->fd_[block,dev]_size from struct block_device.
147 *
148 * Otherwise, we use the passed fd_size= from configfs
149 */
150 inode = file->f_mapping->host;
151 if (S_ISBLK(inode->i_mode)) {
152 struct request_queue *q = bdev_get_queue(inode->i_bdev);
153 unsigned long long dev_size;
154
155 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
156 /*
157 * Determine the number of bytes from i_size_read() minus
158 * one (1) logical sector from underlying struct block_device
159 */
160 dev_size = (i_size_read(file->f_mapping->host) -
161 fd_dev->fd_block_size);
162
163 pr_debug("FILEIO: Using size: %llu bytes from struct"
164 " block_device blocks: %llu logical_block_size: %d\n",
165 dev_size, div_u64(dev_size, fd_dev->fd_block_size),
166 fd_dev->fd_block_size);
167 /*
168 * Check if the underlying struct block_device request_queue supports
169 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
170 * in ATA and we need to set TPE=1
171 */
172 if (blk_queue_discard(q)) {
173 dev->dev_attrib.max_unmap_lba_count =
174 q->limits.max_discard_sectors;
175 /*
176 * Currently hardcoded to 1 in Linux/SCSI code..
177 */
178 dev->dev_attrib.max_unmap_block_desc_count = 1;
179 dev->dev_attrib.unmap_granularity =
180 q->limits.discard_granularity >> 9;
181 dev->dev_attrib.unmap_granularity_alignment =
182 q->limits.discard_alignment;
183 pr_debug("IFILE: BLOCK Discard support available,"
184 " disabled by default\n");
185 }
186 /*
187 * Enable write same emulation for IBLOCK and use 0xFFFF as
188 * the smaller WRITE_SAME(10) only has a two-byte block count.
189 */
190 dev->dev_attrib.max_write_same_len = 0xFFFF;
191
192 if (blk_queue_nonrot(q))
193 dev->dev_attrib.is_nonrot = 1;
194 } else {
195 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
196 pr_err("FILEIO: Missing fd_dev_size="
197 " parameter, and no backing struct"
198 " block_device\n");
199 goto fail;
200 }
201
202 fd_dev->fd_block_size = FD_BLOCKSIZE;
203 /*
204 * Limit UNMAP emulation to 8k Number of LBAs (NoLB)
205 */
206 dev->dev_attrib.max_unmap_lba_count = 0x2000;
207 /*
208 * Currently hardcoded to 1 in Linux/SCSI code..
209 */
210 dev->dev_attrib.max_unmap_block_desc_count = 1;
211 dev->dev_attrib.unmap_granularity = 1;
212 dev->dev_attrib.unmap_granularity_alignment = 0;
213
214 /*
215 * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
216 * based upon struct iovec limit for vfs_writev()
217 */
218 dev->dev_attrib.max_write_same_len = 0x1000;
219 }
220
221 dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
222 dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES;
223 dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
224 dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
225
226 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
227 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
228 " with FDBD_HAS_BUFFERED_IO_WCE\n");
229 dev->dev_attrib.emulate_write_cache = 1;
230 }
231
232 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
233 fd_dev->fd_queue_depth = dev->queue_depth;
234
235 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
236 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
237 fd_dev->fd_dev_name, fd_dev->fd_dev_size);
238
239 return 0;
240 fail:
241 if (fd_dev->fd_file) {
242 filp_close(fd_dev->fd_file, NULL);
243 fd_dev->fd_file = NULL;
244 }
245 return ret;
246 }
247
fd_free_device(struct se_device * dev)248 static void fd_free_device(struct se_device *dev)
249 {
250 struct fd_dev *fd_dev = FD_DEV(dev);
251
252 if (fd_dev->fd_file) {
253 filp_close(fd_dev->fd_file, NULL);
254 fd_dev->fd_file = NULL;
255 }
256
257 kfree(fd_dev);
258 }
259
fd_do_prot_rw(struct se_cmd * cmd,struct fd_prot * fd_prot,int is_write)260 static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot,
261 int is_write)
262 {
263 struct se_device *se_dev = cmd->se_dev;
264 struct fd_dev *dev = FD_DEV(se_dev);
265 struct file *prot_fd = dev->fd_prot_file;
266 loff_t pos = (cmd->t_task_lba * se_dev->prot_length);
267 unsigned char *buf;
268 u32 prot_size;
269 int rc, ret = 1;
270
271 prot_size = (cmd->data_length / se_dev->dev_attrib.block_size) *
272 se_dev->prot_length;
273
274 if (!is_write) {
275 fd_prot->prot_buf = kzalloc(prot_size, GFP_KERNEL);
276 if (!fd_prot->prot_buf) {
277 pr_err("Unable to allocate fd_prot->prot_buf\n");
278 return -ENOMEM;
279 }
280 buf = fd_prot->prot_buf;
281
282 fd_prot->prot_sg_nents = 1;
283 fd_prot->prot_sg = kzalloc(sizeof(struct scatterlist),
284 GFP_KERNEL);
285 if (!fd_prot->prot_sg) {
286 pr_err("Unable to allocate fd_prot->prot_sg\n");
287 kfree(fd_prot->prot_buf);
288 return -ENOMEM;
289 }
290 sg_init_table(fd_prot->prot_sg, fd_prot->prot_sg_nents);
291 sg_set_buf(fd_prot->prot_sg, buf, prot_size);
292 }
293
294 if (is_write) {
295 rc = kernel_write(prot_fd, fd_prot->prot_buf, prot_size, pos);
296 if (rc < 0 || prot_size != rc) {
297 pr_err("kernel_write() for fd_do_prot_rw failed:"
298 " %d\n", rc);
299 ret = -EINVAL;
300 }
301 } else {
302 rc = kernel_read(prot_fd, pos, fd_prot->prot_buf, prot_size);
303 if (rc < 0) {
304 pr_err("kernel_read() for fd_do_prot_rw failed:"
305 " %d\n", rc);
306 ret = -EINVAL;
307 }
308 }
309
310 if (is_write || ret < 0) {
311 kfree(fd_prot->prot_sg);
312 kfree(fd_prot->prot_buf);
313 }
314
315 return ret;
316 }
317
fd_do_rw(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,int is_write)318 static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
319 u32 sgl_nents, int is_write)
320 {
321 struct se_device *se_dev = cmd->se_dev;
322 struct fd_dev *dev = FD_DEV(se_dev);
323 struct file *fd = dev->fd_file;
324 struct scatterlist *sg;
325 struct iovec *iov;
326 mm_segment_t old_fs;
327 loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size);
328 int ret = 0, i;
329
330 iov = kzalloc(sizeof(struct iovec) * sgl_nents, GFP_KERNEL);
331 if (!iov) {
332 pr_err("Unable to allocate fd_do_readv iov[]\n");
333 return -ENOMEM;
334 }
335
336 for_each_sg(sgl, sg, sgl_nents, i) {
337 iov[i].iov_len = sg->length;
338 iov[i].iov_base = kmap(sg_page(sg)) + sg->offset;
339 }
340
341 old_fs = get_fs();
342 set_fs(get_ds());
343
344 if (is_write)
345 ret = vfs_writev(fd, &iov[0], sgl_nents, &pos);
346 else
347 ret = vfs_readv(fd, &iov[0], sgl_nents, &pos);
348
349 set_fs(old_fs);
350
351 for_each_sg(sgl, sg, sgl_nents, i)
352 kunmap(sg_page(sg));
353
354 kfree(iov);
355
356 if (is_write) {
357 if (ret < 0 || ret != cmd->data_length) {
358 pr_err("%s() write returned %d\n", __func__, ret);
359 return (ret < 0 ? ret : -EINVAL);
360 }
361 } else {
362 /*
363 * Return zeros and GOOD status even if the READ did not return
364 * the expected virt_size for struct file w/o a backing struct
365 * block_device.
366 */
367 if (S_ISBLK(file_inode(fd)->i_mode)) {
368 if (ret < 0 || ret != cmd->data_length) {
369 pr_err("%s() returned %d, expecting %u for "
370 "S_ISBLK\n", __func__, ret,
371 cmd->data_length);
372 return (ret < 0 ? ret : -EINVAL);
373 }
374 } else {
375 if (ret < 0) {
376 pr_err("%s() returned %d for non S_ISBLK\n",
377 __func__, ret);
378 return ret;
379 }
380 }
381 }
382 return 1;
383 }
384
385 static sense_reason_t
fd_execute_sync_cache(struct se_cmd * cmd)386 fd_execute_sync_cache(struct se_cmd *cmd)
387 {
388 struct se_device *dev = cmd->se_dev;
389 struct fd_dev *fd_dev = FD_DEV(dev);
390 int immed = (cmd->t_task_cdb[1] & 0x2);
391 loff_t start, end;
392 int ret;
393
394 /*
395 * If the Immediate bit is set, queue up the GOOD response
396 * for this SYNCHRONIZE_CACHE op
397 */
398 if (immed)
399 target_complete_cmd(cmd, SAM_STAT_GOOD);
400
401 /*
402 * Determine if we will be flushing the entire device.
403 */
404 if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
405 start = 0;
406 end = LLONG_MAX;
407 } else {
408 start = cmd->t_task_lba * dev->dev_attrib.block_size;
409 if (cmd->data_length)
410 end = start + cmd->data_length - 1;
411 else
412 end = LLONG_MAX;
413 }
414
415 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
416 if (ret != 0)
417 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
418
419 if (immed)
420 return 0;
421
422 if (ret)
423 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
424 else
425 target_complete_cmd(cmd, SAM_STAT_GOOD);
426
427 return 0;
428 }
429
430 static unsigned char *
fd_setup_write_same_buf(struct se_cmd * cmd,struct scatterlist * sg,unsigned int len)431 fd_setup_write_same_buf(struct se_cmd *cmd, struct scatterlist *sg,
432 unsigned int len)
433 {
434 struct se_device *se_dev = cmd->se_dev;
435 unsigned int block_size = se_dev->dev_attrib.block_size;
436 unsigned int i = 0, end;
437 unsigned char *buf, *p, *kmap_buf;
438
439 buf = kzalloc(min_t(unsigned int, len, PAGE_SIZE), GFP_KERNEL);
440 if (!buf) {
441 pr_err("Unable to allocate fd_execute_write_same buf\n");
442 return NULL;
443 }
444
445 kmap_buf = kmap(sg_page(sg)) + sg->offset;
446 if (!kmap_buf) {
447 pr_err("kmap() failed in fd_setup_write_same\n");
448 kfree(buf);
449 return NULL;
450 }
451 /*
452 * Fill local *buf to contain multiple WRITE_SAME blocks up to
453 * min(len, PAGE_SIZE)
454 */
455 p = buf;
456 end = min_t(unsigned int, len, PAGE_SIZE);
457
458 while (i < end) {
459 memcpy(p, kmap_buf, block_size);
460
461 i += block_size;
462 p += block_size;
463 }
464 kunmap(sg_page(sg));
465
466 return buf;
467 }
468
469 static sense_reason_t
fd_execute_write_same(struct se_cmd * cmd)470 fd_execute_write_same(struct se_cmd *cmd)
471 {
472 struct se_device *se_dev = cmd->se_dev;
473 struct fd_dev *fd_dev = FD_DEV(se_dev);
474 struct file *f = fd_dev->fd_file;
475 struct scatterlist *sg;
476 struct iovec *iov;
477 mm_segment_t old_fs;
478 sector_t nolb = sbc_get_write_same_sectors(cmd);
479 loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
480 unsigned int len, len_tmp, iov_num;
481 int i, rc;
482 unsigned char *buf;
483
484 if (!nolb) {
485 target_complete_cmd(cmd, SAM_STAT_GOOD);
486 return 0;
487 }
488 sg = &cmd->t_data_sg[0];
489
490 if (cmd->t_data_nents > 1 ||
491 sg->length != cmd->se_dev->dev_attrib.block_size) {
492 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
493 " block_size: %u\n", cmd->t_data_nents, sg->length,
494 cmd->se_dev->dev_attrib.block_size);
495 return TCM_INVALID_CDB_FIELD;
496 }
497
498 len = len_tmp = nolb * se_dev->dev_attrib.block_size;
499 iov_num = DIV_ROUND_UP(len, PAGE_SIZE);
500
501 buf = fd_setup_write_same_buf(cmd, sg, len);
502 if (!buf)
503 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
504
505 iov = vzalloc(sizeof(struct iovec) * iov_num);
506 if (!iov) {
507 pr_err("Unable to allocate fd_execute_write_same iovecs\n");
508 kfree(buf);
509 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
510 }
511 /*
512 * Map the single fabric received scatterlist block now populated
513 * in *buf into each iovec for I/O submission.
514 */
515 for (i = 0; i < iov_num; i++) {
516 iov[i].iov_base = buf;
517 iov[i].iov_len = min_t(unsigned int, len_tmp, PAGE_SIZE);
518 len_tmp -= iov[i].iov_len;
519 }
520
521 old_fs = get_fs();
522 set_fs(get_ds());
523 rc = vfs_writev(f, &iov[0], iov_num, &pos);
524 set_fs(old_fs);
525
526 vfree(iov);
527 kfree(buf);
528
529 if (rc < 0 || rc != len) {
530 pr_err("vfs_writev() returned %d for write same\n", rc);
531 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
532 }
533
534 target_complete_cmd(cmd, SAM_STAT_GOOD);
535 return 0;
536 }
537
538 static int
fd_do_prot_fill(struct se_device * se_dev,sector_t lba,sector_t nolb,void * buf,size_t bufsize)539 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
540 void *buf, size_t bufsize)
541 {
542 struct fd_dev *fd_dev = FD_DEV(se_dev);
543 struct file *prot_fd = fd_dev->fd_prot_file;
544 sector_t prot_length, prot;
545 loff_t pos = lba * se_dev->prot_length;
546
547 if (!prot_fd) {
548 pr_err("Unable to locate fd_dev->fd_prot_file\n");
549 return -ENODEV;
550 }
551
552 prot_length = nolb * se_dev->prot_length;
553
554 for (prot = 0; prot < prot_length;) {
555 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
556 ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
557
558 if (ret != len) {
559 pr_err("vfs_write to prot file failed: %zd\n", ret);
560 return ret < 0 ? ret : -ENODEV;
561 }
562 prot += ret;
563 }
564
565 return 0;
566 }
567
568 static int
fd_do_prot_unmap(struct se_cmd * cmd,sector_t lba,sector_t nolb)569 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
570 {
571 void *buf;
572 int rc;
573
574 buf = (void *)__get_free_page(GFP_KERNEL);
575 if (!buf) {
576 pr_err("Unable to allocate FILEIO prot buf\n");
577 return -ENOMEM;
578 }
579 memset(buf, 0xff, PAGE_SIZE);
580
581 rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
582
583 free_page((unsigned long)buf);
584
585 return rc;
586 }
587
588 static sense_reason_t
fd_do_unmap(struct se_cmd * cmd,void * priv,sector_t lba,sector_t nolb)589 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
590 {
591 struct file *file = priv;
592 struct inode *inode = file->f_mapping->host;
593 int ret;
594
595 if (!nolb) {
596 return 0;
597 }
598
599 if (cmd->se_dev->dev_attrib.pi_prot_type) {
600 ret = fd_do_prot_unmap(cmd, lba, nolb);
601 if (ret)
602 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
603 }
604
605 if (S_ISBLK(inode->i_mode)) {
606 /* The backend is block device, use discard */
607 struct block_device *bdev = inode->i_bdev;
608
609 ret = blkdev_issue_discard(bdev, lba,
610 nolb, GFP_KERNEL, 0);
611 if (ret < 0) {
612 pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
613 ret);
614 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
615 }
616 } else {
617 /* The backend is normal file, use fallocate */
618 struct se_device *se_dev = cmd->se_dev;
619 loff_t pos = lba * se_dev->dev_attrib.block_size;
620 unsigned int len = nolb * se_dev->dev_attrib.block_size;
621 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
622
623 if (!file->f_op->fallocate)
624 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
625
626 ret = file->f_op->fallocate(file, mode, pos, len);
627 if (ret < 0) {
628 pr_warn("FILEIO: fallocate() failed: %d\n", ret);
629 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
630 }
631 }
632
633 return 0;
634 }
635
636 static sense_reason_t
fd_execute_write_same_unmap(struct se_cmd * cmd)637 fd_execute_write_same_unmap(struct se_cmd *cmd)
638 {
639 struct se_device *se_dev = cmd->se_dev;
640 struct fd_dev *fd_dev = FD_DEV(se_dev);
641 struct file *file = fd_dev->fd_file;
642 sector_t lba = cmd->t_task_lba;
643 sector_t nolb = sbc_get_write_same_sectors(cmd);
644 int ret;
645
646 if (!nolb) {
647 target_complete_cmd(cmd, SAM_STAT_GOOD);
648 return 0;
649 }
650
651 ret = fd_do_unmap(cmd, file, lba, nolb);
652 if (ret)
653 return ret;
654
655 target_complete_cmd(cmd, GOOD);
656 return 0;
657 }
658
659 static sense_reason_t
fd_execute_unmap(struct se_cmd * cmd)660 fd_execute_unmap(struct se_cmd *cmd)
661 {
662 struct file *file = FD_DEV(cmd->se_dev)->fd_file;
663
664 return sbc_execute_unmap(cmd, fd_do_unmap, file);
665 }
666
667 static sense_reason_t
fd_execute_rw(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)668 fd_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_prot fd_prot;
673 sense_reason_t rc;
674 int ret = 0;
675 /*
676 * We are currently limited by the number of iovecs (2048) per
677 * single vfs_[writev,readv] call.
678 */
679 if (cmd->data_length > FD_MAX_BYTES) {
680 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
681 "FD_MAX_BYTES: %u iovec count limitiation\n",
682 cmd->data_length, FD_MAX_BYTES);
683 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
684 }
685 /*
686 * Call vectorized fileio functions to map struct scatterlist
687 * physical memory addresses to struct iovec virtual memory.
688 */
689 if (data_direction == DMA_FROM_DEVICE) {
690 memset(&fd_prot, 0, sizeof(struct fd_prot));
691
692 if (cmd->prot_type) {
693 ret = fd_do_prot_rw(cmd, &fd_prot, false);
694 if (ret < 0)
695 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
696 }
697
698 ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
699
700 if (ret > 0 && cmd->prot_type) {
701 u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
702
703 rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors,
704 0, fd_prot.prot_sg, 0);
705 if (rc) {
706 kfree(fd_prot.prot_sg);
707 kfree(fd_prot.prot_buf);
708 return rc;
709 }
710 kfree(fd_prot.prot_sg);
711 kfree(fd_prot.prot_buf);
712 }
713 } else {
714 memset(&fd_prot, 0, sizeof(struct fd_prot));
715
716 if (cmd->prot_type) {
717 u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
718
719 ret = fd_do_prot_rw(cmd, &fd_prot, false);
720 if (ret < 0)
721 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
722
723 rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors,
724 0, fd_prot.prot_sg, 0);
725 if (rc) {
726 kfree(fd_prot.prot_sg);
727 kfree(fd_prot.prot_buf);
728 return rc;
729 }
730 }
731
732 ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
733 /*
734 * Perform implicit vfs_fsync_range() for fd_do_writev() ops
735 * for SCSI WRITEs with Forced Unit Access (FUA) set.
736 * Allow this to happen independent of WCE=0 setting.
737 */
738 if (ret > 0 &&
739 dev->dev_attrib.emulate_fua_write > 0 &&
740 (cmd->se_cmd_flags & SCF_FUA)) {
741 struct fd_dev *fd_dev = FD_DEV(dev);
742 loff_t start = cmd->t_task_lba *
743 dev->dev_attrib.block_size;
744 loff_t end;
745
746 if (cmd->data_length)
747 end = start + cmd->data_length - 1;
748 else
749 end = LLONG_MAX;
750
751 vfs_fsync_range(fd_dev->fd_file, start, end, 1);
752 }
753
754 if (ret > 0 && cmd->prot_type) {
755 ret = fd_do_prot_rw(cmd, &fd_prot, true);
756 if (ret < 0)
757 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
758 }
759 }
760
761 if (ret < 0) {
762 kfree(fd_prot.prot_sg);
763 kfree(fd_prot.prot_buf);
764 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
765 }
766
767 target_complete_cmd(cmd, SAM_STAT_GOOD);
768 return 0;
769 }
770
771 enum {
772 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
773 };
774
775 static match_table_t tokens = {
776 {Opt_fd_dev_name, "fd_dev_name=%s"},
777 {Opt_fd_dev_size, "fd_dev_size=%s"},
778 {Opt_fd_buffered_io, "fd_buffered_io=%d"},
779 {Opt_err, NULL}
780 };
781
fd_set_configfs_dev_params(struct se_device * dev,const char * page,ssize_t count)782 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
783 const char *page, ssize_t count)
784 {
785 struct fd_dev *fd_dev = FD_DEV(dev);
786 char *orig, *ptr, *arg_p, *opts;
787 substring_t args[MAX_OPT_ARGS];
788 int ret = 0, arg, token;
789
790 opts = kstrdup(page, GFP_KERNEL);
791 if (!opts)
792 return -ENOMEM;
793
794 orig = opts;
795
796 while ((ptr = strsep(&opts, ",\n")) != NULL) {
797 if (!*ptr)
798 continue;
799
800 token = match_token(ptr, tokens, args);
801 switch (token) {
802 case Opt_fd_dev_name:
803 if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
804 FD_MAX_DEV_NAME) == 0) {
805 ret = -EINVAL;
806 break;
807 }
808 pr_debug("FILEIO: Referencing Path: %s\n",
809 fd_dev->fd_dev_name);
810 fd_dev->fbd_flags |= FBDF_HAS_PATH;
811 break;
812 case Opt_fd_dev_size:
813 arg_p = match_strdup(&args[0]);
814 if (!arg_p) {
815 ret = -ENOMEM;
816 break;
817 }
818 ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
819 kfree(arg_p);
820 if (ret < 0) {
821 pr_err("kstrtoull() failed for"
822 " fd_dev_size=\n");
823 goto out;
824 }
825 pr_debug("FILEIO: Referencing Size: %llu"
826 " bytes\n", fd_dev->fd_dev_size);
827 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
828 break;
829 case Opt_fd_buffered_io:
830 ret = match_int(args, &arg);
831 if (ret)
832 goto out;
833 if (arg != 1) {
834 pr_err("bogus fd_buffered_io=%d value\n", arg);
835 ret = -EINVAL;
836 goto out;
837 }
838
839 pr_debug("FILEIO: Using buffered I/O"
840 " operations for struct fd_dev\n");
841
842 fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
843 break;
844 default:
845 break;
846 }
847 }
848
849 out:
850 kfree(orig);
851 return (!ret) ? count : ret;
852 }
853
fd_show_configfs_dev_params(struct se_device * dev,char * b)854 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
855 {
856 struct fd_dev *fd_dev = FD_DEV(dev);
857 ssize_t bl = 0;
858
859 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
860 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s\n",
861 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
862 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
863 "Buffered-WCE" : "O_DSYNC");
864 return bl;
865 }
866
fd_get_blocks(struct se_device * dev)867 static sector_t fd_get_blocks(struct se_device *dev)
868 {
869 struct fd_dev *fd_dev = FD_DEV(dev);
870 struct file *f = fd_dev->fd_file;
871 struct inode *i = f->f_mapping->host;
872 unsigned long long dev_size;
873 /*
874 * When using a file that references an underlying struct block_device,
875 * ensure dev_size is always based on the current inode size in order
876 * to handle underlying block_device resize operations.
877 */
878 if (S_ISBLK(i->i_mode))
879 dev_size = i_size_read(i);
880 else
881 dev_size = fd_dev->fd_dev_size;
882
883 return div_u64(dev_size - dev->dev_attrib.block_size,
884 dev->dev_attrib.block_size);
885 }
886
fd_init_prot(struct se_device * dev)887 static int fd_init_prot(struct se_device *dev)
888 {
889 struct fd_dev *fd_dev = FD_DEV(dev);
890 struct file *prot_file, *file = fd_dev->fd_file;
891 struct inode *inode;
892 int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
893 char buf[FD_MAX_DEV_PROT_NAME];
894
895 if (!file) {
896 pr_err("Unable to locate fd_dev->fd_file\n");
897 return -ENODEV;
898 }
899
900 inode = file->f_mapping->host;
901 if (S_ISBLK(inode->i_mode)) {
902 pr_err("FILEIO Protection emulation only supported on"
903 " !S_ISBLK\n");
904 return -ENOSYS;
905 }
906
907 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
908 flags &= ~O_DSYNC;
909
910 snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
911 fd_dev->fd_dev_name);
912
913 prot_file = filp_open(buf, flags, 0600);
914 if (IS_ERR(prot_file)) {
915 pr_err("filp_open(%s) failed\n", buf);
916 ret = PTR_ERR(prot_file);
917 return ret;
918 }
919 fd_dev->fd_prot_file = prot_file;
920
921 return 0;
922 }
923
fd_format_prot(struct se_device * dev)924 static int fd_format_prot(struct se_device *dev)
925 {
926 unsigned char *buf;
927 int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
928 int ret;
929
930 if (!dev->dev_attrib.pi_prot_type) {
931 pr_err("Unable to format_prot while pi_prot_type == 0\n");
932 return -ENODEV;
933 }
934
935 buf = vzalloc(unit_size);
936 if (!buf) {
937 pr_err("Unable to allocate FILEIO prot buf\n");
938 return -ENOMEM;
939 }
940
941 pr_debug("Using FILEIO prot_length: %llu\n",
942 (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
943 dev->prot_length);
944
945 memset(buf, 0xff, unit_size);
946 ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
947 buf, unit_size);
948 vfree(buf);
949 return ret;
950 }
951
fd_free_prot(struct se_device * dev)952 static void fd_free_prot(struct se_device *dev)
953 {
954 struct fd_dev *fd_dev = FD_DEV(dev);
955
956 if (!fd_dev->fd_prot_file)
957 return;
958
959 filp_close(fd_dev->fd_prot_file, NULL);
960 fd_dev->fd_prot_file = NULL;
961 }
962
963 static struct sbc_ops fd_sbc_ops = {
964 .execute_rw = fd_execute_rw,
965 .execute_sync_cache = fd_execute_sync_cache,
966 .execute_write_same = fd_execute_write_same,
967 .execute_write_same_unmap = fd_execute_write_same_unmap,
968 .execute_unmap = fd_execute_unmap,
969 };
970
971 static sense_reason_t
fd_parse_cdb(struct se_cmd * cmd)972 fd_parse_cdb(struct se_cmd *cmd)
973 {
974 return sbc_parse_cdb(cmd, &fd_sbc_ops);
975 }
976
977 static struct se_subsystem_api fileio_template = {
978 .name = "fileio",
979 .inquiry_prod = "FILEIO",
980 .inquiry_rev = FD_VERSION,
981 .owner = THIS_MODULE,
982 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
983 .attach_hba = fd_attach_hba,
984 .detach_hba = fd_detach_hba,
985 .alloc_device = fd_alloc_device,
986 .configure_device = fd_configure_device,
987 .free_device = fd_free_device,
988 .parse_cdb = fd_parse_cdb,
989 .set_configfs_dev_params = fd_set_configfs_dev_params,
990 .show_configfs_dev_params = fd_show_configfs_dev_params,
991 .get_device_type = sbc_get_device_type,
992 .get_blocks = fd_get_blocks,
993 .init_prot = fd_init_prot,
994 .format_prot = fd_format_prot,
995 .free_prot = fd_free_prot,
996 };
997
fileio_module_init(void)998 static int __init fileio_module_init(void)
999 {
1000 return transport_subsystem_register(&fileio_template);
1001 }
1002
fileio_module_exit(void)1003 static void __exit fileio_module_exit(void)
1004 {
1005 transport_subsystem_release(&fileio_template);
1006 }
1007
1008 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
1009 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1010 MODULE_LICENSE("GPL");
1011
1012 module_init(fileio_module_init);
1013 module_exit(fileio_module_exit);
1014