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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/version.h>
30#include <linux/string.h>
31#include <linux/parser.h>
32#include <linux/timer.h>
33#include <linux/blkdev.h>
34#include <linux/slab.h>
35#include <linux/spinlock.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_device.h>
41#include <target/target_core_transport.h>
42
43#include "target_core_file.h"
44
45static struct se_subsystem_api fileio_template;
46
47/* fd_attach_hba(): (Part of se_subsystem_api_t template)
48 *
49 *
50 */
51static int fd_attach_hba(struct se_hba *hba, u32 host_id)
52{
53 struct fd_host *fd_host;
54
55 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
56 if (!fd_host) {
57 pr_err("Unable to allocate memory for struct fd_host\n");
58 return -ENOMEM;
59 }
60
61 fd_host->fd_host_id = host_id;
62
63 hba->hba_ptr = fd_host;
64
65 pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
66 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
67 TARGET_CORE_MOD_VERSION);
68 pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic"
69 " MaxSectors: %u\n",
70 hba->hba_id, fd_host->fd_host_id, FD_MAX_SECTORS);
71
72 return 0;
73}
74
75static 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
86static void *fd_allocate_virtdevice(struct se_hba *hba, const char *name)
87{
88 struct fd_dev *fd_dev;
89 struct fd_host *fd_host = (struct 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;
102}
103
104/* fd_create_virtdevice(): (Part of se_subsystem_api_t template)
105 *
106 *
107 */
108static struct se_device *fd_create_virtdevice(
109 struct se_hba *hba,
110 struct se_subsystem_dev *se_dev,
111 void *p)
112{
113 char *dev_p = NULL;
114 struct se_device *dev;
115 struct se_dev_limits dev_limits;
116 struct queue_limits *limits;
117 struct fd_dev *fd_dev = (struct fd_dev *) p;
118 struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr;
119 mm_segment_t old_fs;
120 struct file *file;
121 struct inode *inode = NULL;
122 int dev_flags = 0, flags, ret = -EINVAL;
123
124 memset(&dev_limits, 0, sizeof(struct se_dev_limits));
125
126 old_fs = get_fs();
127 set_fs(get_ds());
128 dev_p = getname(fd_dev->fd_dev_name);
129 set_fs(old_fs);
130
131 if (IS_ERR(dev_p)) {
132 pr_err("getname(%s) failed: %lu\n",
133 fd_dev->fd_dev_name, IS_ERR(dev_p));
134 ret = PTR_ERR(dev_p);
135 goto fail;
136 }
137#if 0
138 if (di->no_create_file)
139 flags = O_RDWR | O_LARGEFILE;
140 else
141 flags = O_RDWR | O_CREAT | O_LARGEFILE;
142#else
143 flags = O_RDWR | O_CREAT | O_LARGEFILE;
144#endif
145/* flags |= O_DIRECT; */
146 /*
147 * If fd_buffered_io=1 has not been set explicitly (the default),
148 * use O_SYNC to force FILEIO writes to disk.
149 */
150 if (!(fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO))
151 flags |= O_SYNC;
152
153 file = filp_open(dev_p, flags, 0600);
154 if (IS_ERR(file)) {
155 pr_err("filp_open(%s) failed\n", dev_p);
156 ret = PTR_ERR(file);
157 goto fail;
158 }
159 if (!file || !file->f_dentry) {
160 pr_err("filp_open(%s) failed\n", dev_p);
161 goto fail;
162 }
163 fd_dev->fd_file = file;
164 /*
165 * If using a block backend with this struct file, we extract
166 * fd_dev->fd_[block,dev]_size from struct block_device.
167 *
168 * Otherwise, we use the passed fd_size= from configfs
169 */
170 inode = file->f_mapping->host;
171 if (S_ISBLK(inode->i_mode)) {
172 struct request_queue *q;
173 /*
174 * Setup the local scope queue_limits from struct request_queue->limits
175 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
176 */
177 q = bdev_get_queue(inode->i_bdev);
178 limits = &dev_limits.limits;
179 limits->logical_block_size = bdev_logical_block_size(inode->i_bdev);
180 limits->max_hw_sectors = queue_max_hw_sectors(q);
181 limits->max_sectors = queue_max_sectors(q);
182 /*
183 * Determine the number of bytes from i_size_read() minus
184 * one (1) logical sector from underlying struct block_device
185 */
186 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
187 fd_dev->fd_dev_size = (i_size_read(file->f_mapping->host) -
188 fd_dev->fd_block_size);
189
190 pr_debug("FILEIO: Using size: %llu bytes from struct"
191 " block_device blocks: %llu logical_block_size: %d\n",
192 fd_dev->fd_dev_size,
193 div_u64(fd_dev->fd_dev_size, fd_dev->fd_block_size),
194 fd_dev->fd_block_size);
195 } else {
196 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
197 pr_err("FILEIO: Missing fd_dev_size="
198 " parameter, and no backing struct"
199 " block_device\n");
200 goto fail;
201 }
202
203 limits = &dev_limits.limits;
204 limits->logical_block_size = FD_BLOCKSIZE;
205 limits->max_hw_sectors = FD_MAX_SECTORS;
206 limits->max_sectors = FD_MAX_SECTORS;
207 fd_dev->fd_block_size = FD_BLOCKSIZE;
208 }
209
210 dev_limits.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
211 dev_limits.queue_depth = FD_DEVICE_QUEUE_DEPTH;
212
213 dev = transport_add_device_to_core_hba(hba, &fileio_template,
214 se_dev, dev_flags, fd_dev,
215 &dev_limits, "FILEIO", FD_VERSION);
216 if (!dev)
217 goto fail;
218
219 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
220 fd_dev->fd_queue_depth = dev->queue_depth;
221
222 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
223 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
224 fd_dev->fd_dev_name, fd_dev->fd_dev_size);
225
226 putname(dev_p);
227 return dev;
228fail:
229 if (fd_dev->fd_file) {
230 filp_close(fd_dev->fd_file, NULL);
231 fd_dev->fd_file = NULL;
232 }
233 putname(dev_p);
234 return ERR_PTR(ret);
235}
236
237/* fd_free_device(): (Part of se_subsystem_api_t template)
238 *
239 *
240 */
241static void fd_free_device(void *p)
242{
243 struct fd_dev *fd_dev = (struct fd_dev *) p;
244
245 if (fd_dev->fd_file) {
246 filp_close(fd_dev->fd_file, NULL);
247 fd_dev->fd_file = NULL;
248 }
249
250 kfree(fd_dev);
251}
252
253static inline struct fd_request *FILE_REQ(struct se_task *task)
254{
255 return container_of(task, struct fd_request, fd_task);
256}
257
258
259static struct se_task *
260fd_alloc_task(unsigned char *cdb)
261{
262 struct fd_request *fd_req;
263
264 fd_req = kzalloc(sizeof(struct fd_request), GFP_KERNEL);
265 if (!fd_req) {
266 pr_err("Unable to allocate struct fd_request\n");
267 return NULL;
268 }
269
270 return &fd_req->fd_task;
271}
272
273static int fd_do_readv(struct se_task *task)
274{
275 struct fd_request *req = FILE_REQ(task);
276 struct fd_dev *dev = req->fd_task.se_dev->dev_ptr;
277 struct file *fd = dev->fd_file;
278 struct scatterlist *sg = task->task_sg;
279 struct iovec *iov;
280 mm_segment_t old_fs;
281 loff_t pos = (task->task_lba *
282 task->se_dev->se_sub_dev->se_dev_attrib.block_size);
283 int ret = 0, i;
284
285 iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL);
286 if (!iov) {
287 pr_err("Unable to allocate fd_do_readv iov[]\n");
288 return -ENOMEM;
289 }
290
291 for (i = 0; i < task->task_sg_nents; i++) {
292 iov[i].iov_len = sg[i].length;
293 iov[i].iov_base = sg_virt(&sg[i]);
294 }
295
296 old_fs = get_fs();
297 set_fs(get_ds());
298 ret = vfs_readv(fd, &iov[0], task->task_sg_nents, &pos);
299 set_fs(old_fs);
300
301 kfree(iov);
302 /*
303 * Return zeros and GOOD status even if the READ did not return
304 * the expected virt_size for struct file w/o a backing struct
305 * block_device.
306 */
307 if (S_ISBLK(fd->f_dentry->d_inode->i_mode)) {
308 if (ret < 0 || ret != task->task_size) {
309 pr_err("vfs_readv() returned %d,"
310 " expecting %d for S_ISBLK\n", ret,
311 (int)task->task_size);
312 return (ret < 0 ? ret : -EINVAL);
313 }
314 } else {
315 if (ret < 0) {
316 pr_err("vfs_readv() returned %d for non"
317 " S_ISBLK\n", ret);
318 return ret;
319 }
320 }
321
322 return 1;
323}
324
325static int fd_do_writev(struct se_task *task)
326{
327 struct fd_request *req = FILE_REQ(task);
328 struct fd_dev *dev = req->fd_task.se_dev->dev_ptr;
329 struct file *fd = dev->fd_file;
330 struct scatterlist *sg = task->task_sg;
331 struct iovec *iov;
332 mm_segment_t old_fs;
333 loff_t pos = (task->task_lba *
334 task->se_dev->se_sub_dev->se_dev_attrib.block_size);
335 int ret, i = 0;
336
337 iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL);
338 if (!iov) {
339 pr_err("Unable to allocate fd_do_writev iov[]\n");
340 return -ENOMEM;
341 }
342
343 for (i = 0; i < task->task_sg_nents; i++) {
344 iov[i].iov_len = sg[i].length;
345 iov[i].iov_base = sg_virt(&sg[i]);
346 }
347
348 old_fs = get_fs();
349 set_fs(get_ds());
350 ret = vfs_writev(fd, &iov[0], task->task_sg_nents, &pos);
351 set_fs(old_fs);
352
353 kfree(iov);
354
355 if (ret < 0 || ret != task->task_size) {
356 pr_err("vfs_writev() returned %d\n", ret);
357 return (ret < 0 ? ret : -EINVAL);
358 }
359
360 return 1;
361}
362
363static void fd_emulate_sync_cache(struct se_task *task)
364{
365 struct se_cmd *cmd = task->task_se_cmd;
366 struct se_device *dev = cmd->se_dev;
367 struct fd_dev *fd_dev = dev->dev_ptr;
368 int immed = (cmd->t_task_cdb[1] & 0x2);
369 loff_t start, end;
370 int ret;
371
372 /*
373 * If the Immediate bit is set, queue up the GOOD response
374 * for this SYNCHRONIZE_CACHE op
375 */
376 if (immed)
377 transport_complete_sync_cache(cmd, 1);
378
379 /*
380 * Determine if we will be flushing the entire device.
381 */
382 if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
383 start = 0;
384 end = LLONG_MAX;
385 } else {
386 start = cmd->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
387 if (cmd->data_length)
388 end = start + cmd->data_length;
389 else
390 end = LLONG_MAX;
391 }
392
393 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
394 if (ret != 0)
395 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
396
397 if (!immed)
398 transport_complete_sync_cache(cmd, ret == 0);
399}
400
401/*
402 * Tell TCM Core that we are capable of WriteCache emulation for
403 * an underlying struct se_device.
404 */
405static int fd_emulated_write_cache(struct se_device *dev)
406{
407 return 1;
408}
409
410static int fd_emulated_dpo(struct se_device *dev)
411{
412 return 0;
413}
414/*
415 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs
416 * for TYPE_DISK.
417 */
418static int fd_emulated_fua_write(struct se_device *dev)
419{
420 return 1;
421}
422
423static int fd_emulated_fua_read(struct se_device *dev)
424{
425 return 0;
426}
427
428/*
429 * WRITE Force Unit Access (FUA) emulation on a per struct se_task
430 * LBA range basis..
431 */
432static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task)
433{
434 struct se_device *dev = cmd->se_dev;
435 struct fd_dev *fd_dev = dev->dev_ptr;
436 loff_t start = task->task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
437 loff_t end = start + task->task_size;
438 int ret;
439
440 pr_debug("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n",
441 task->task_lba, task->task_size);
442
443 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
444 if (ret != 0)
445 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
446}
447
448static int fd_do_task(struct se_task *task)
449{
450 struct se_cmd *cmd = task->task_se_cmd;
451 struct se_device *dev = cmd->se_dev;
452 int ret = 0;
453
454 /*
455 * Call vectorized fileio functions to map struct scatterlist
456 * physical memory addresses to struct iovec virtual memory.
457 */
458 if (task->task_data_direction == DMA_FROM_DEVICE) {
459 ret = fd_do_readv(task);
460 } else {
461 ret = fd_do_writev(task);
462
463 if (ret > 0 &&
464 dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0 &&
465 dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
466 cmd->t_tasks_fua) {
467 /*
468 * We might need to be a bit smarter here
469 * and return some sense data to let the initiator
470 * know the FUA WRITE cache sync failed..?
471 */
472 fd_emulate_write_fua(cmd, task);
473 }
474
475 }
476
477 if (ret < 0)
478 return ret;
479 if (ret) {
480 task->task_scsi_status = GOOD;
481 transport_complete_task(task, 1);
482 }
483 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
484}
485
486/* fd_free_task(): (Part of se_subsystem_api_t template)
487 *
488 *
489 */
490static void fd_free_task(struct se_task *task)
491{
492 struct fd_request *req = FILE_REQ(task);
493
494 kfree(req);
495}
496
497enum {
498 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
499};
500
501static match_table_t tokens = {
502 {Opt_fd_dev_name, "fd_dev_name=%s"},
503 {Opt_fd_dev_size, "fd_dev_size=%s"},
504 {Opt_fd_buffered_io, "fd_buffered_io=%d"},
505 {Opt_err, NULL}
506};
507
508static ssize_t fd_set_configfs_dev_params(
509 struct se_hba *hba,
510 struct se_subsystem_dev *se_dev,
511 const char *page, ssize_t count)
512{
513 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
514 char *orig, *ptr, *arg_p, *opts;
515 substring_t args[MAX_OPT_ARGS];
516 int ret = 0, arg, token;
517
518 opts = kstrdup(page, GFP_KERNEL);
519 if (!opts)
520 return -ENOMEM;
521
522 orig = opts;
523
524 while ((ptr = strsep(&opts, ",")) != NULL) {
525 if (!*ptr)
526 continue;
527
528 token = match_token(ptr, tokens, args);
529 switch (token) {
530 case Opt_fd_dev_name:
531 arg_p = match_strdup(&args[0]);
532 if (!arg_p) {
533 ret = -ENOMEM;
534 break;
535 }
536 snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME,
537 "%s", arg_p);
538 kfree(arg_p);
539 pr_debug("FILEIO: Referencing Path: %s\n",
540 fd_dev->fd_dev_name);
541 fd_dev->fbd_flags |= FBDF_HAS_PATH;
542 break;
543 case Opt_fd_dev_size:
544 arg_p = match_strdup(&args[0]);
545 if (!arg_p) {
546 ret = -ENOMEM;
547 break;
548 }
549 ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size);
550 kfree(arg_p);
551 if (ret < 0) {
552 pr_err("strict_strtoull() failed for"
553 " fd_dev_size=\n");
554 goto out;
555 }
556 pr_debug("FILEIO: Referencing Size: %llu"
557 " bytes\n", fd_dev->fd_dev_size);
558 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
559 break;
560 case Opt_fd_buffered_io:
561 match_int(args, &arg);
562 if (arg != 1) {
563 pr_err("bogus fd_buffered_io=%d value\n", arg);
564 ret = -EINVAL;
565 goto out;
566 }
567
568 pr_debug("FILEIO: Using buffered I/O"
569 " operations for struct fd_dev\n");
570
571 fd_dev->fbd_flags |= FDBD_USE_BUFFERED_IO;
572 break;
573 default:
574 break;
575 }
576 }
577
578out:
579 kfree(orig);
580 return (!ret) ? count : ret;
581}
582
583static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev)
584{
585 struct fd_dev *fd_dev = (struct fd_dev *) se_dev->se_dev_su_ptr;
586
587 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
588 pr_err("Missing fd_dev_name=\n");
589 return -EINVAL;
590 }
591
592 return 0;
593}
594
595static ssize_t fd_show_configfs_dev_params(
596 struct se_hba *hba,
597 struct se_subsystem_dev *se_dev,
598 char *b)
599{
600 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
601 ssize_t bl = 0;
602
603 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
604 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s\n",
605 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
606 (fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO) ?
607 "Buffered" : "Synchronous");
608 return bl;
609}
610
611/* fd_get_cdb(): (Part of se_subsystem_api_t template)
612 *
613 *
614 */
615static unsigned char *fd_get_cdb(struct se_task *task)
616{
617 struct fd_request *req = FILE_REQ(task);
618
619 return req->fd_scsi_cdb;
620}
621
622/* fd_get_device_rev(): (Part of se_subsystem_api_t template)
623 *
624 *
625 */
626static u32 fd_get_device_rev(struct se_device *dev)
627{
628 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
629}
630
631/* fd_get_device_type(): (Part of se_subsystem_api_t template)
632 *
633 *
634 */
635static u32 fd_get_device_type(struct se_device *dev)
636{
637 return TYPE_DISK;
638}
639
640static sector_t fd_get_blocks(struct se_device *dev)
641{
642 struct fd_dev *fd_dev = dev->dev_ptr;
643 unsigned long long blocks_long = div_u64(fd_dev->fd_dev_size,
644 dev->se_sub_dev->se_dev_attrib.block_size);
645
646 return blocks_long;
647}
648
649static struct se_subsystem_api fileio_template = {
650 .name = "fileio",
651 .owner = THIS_MODULE,
652 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
653 .attach_hba = fd_attach_hba,
654 .detach_hba = fd_detach_hba,
655 .allocate_virtdevice = fd_allocate_virtdevice,
656 .create_virtdevice = fd_create_virtdevice,
657 .free_device = fd_free_device,
658 .dpo_emulated = fd_emulated_dpo,
659 .fua_write_emulated = fd_emulated_fua_write,
660 .fua_read_emulated = fd_emulated_fua_read,
661 .write_cache_emulated = fd_emulated_write_cache,
662 .alloc_task = fd_alloc_task,
663 .do_task = fd_do_task,
664 .do_sync_cache = fd_emulate_sync_cache,
665 .free_task = fd_free_task,
666 .check_configfs_dev_params = fd_check_configfs_dev_params,
667 .set_configfs_dev_params = fd_set_configfs_dev_params,
668 .show_configfs_dev_params = fd_show_configfs_dev_params,
669 .get_cdb = fd_get_cdb,
670 .get_device_rev = fd_get_device_rev,
671 .get_device_type = fd_get_device_type,
672 .get_blocks = fd_get_blocks,
673};
674
675static int __init fileio_module_init(void)
676{
677 return transport_subsystem_register(&fileio_template);
678}
679
680static void fileio_module_exit(void)
681{
682 transport_subsystem_release(&fileio_template);
683}
684
685MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
686MODULE_AUTHOR("nab@Linux-iSCSI.org");
687MODULE_LICENSE("GPL");
688
689module_init(fileio_module_init);
690module_exit(fileio_module_exit);
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 aio_cmd->bvecs[i].bv_page = sg_page(sg);
285 aio_cmd->bvecs[i].bv_len = sg->length;
286 aio_cmd->bvecs[i].bv_offset = sg->offset;
287
288 len += sg->length;
289 }
290
291 iov_iter_bvec(&iter, is_write, aio_cmd->bvecs, sgl_nents, len);
292
293 aio_cmd->cmd = cmd;
294 aio_cmd->len = len;
295 aio_cmd->iocb.ki_pos = cmd->t_task_lba * dev->dev_attrib.block_size;
296 aio_cmd->iocb.ki_filp = file;
297 aio_cmd->iocb.ki_complete = cmd_rw_aio_complete;
298 aio_cmd->iocb.ki_flags = IOCB_DIRECT;
299
300 if (is_write && (cmd->se_cmd_flags & SCF_FUA))
301 aio_cmd->iocb.ki_flags |= IOCB_DSYNC;
302
303 if (is_write)
304 ret = call_write_iter(file, &aio_cmd->iocb, &iter);
305 else
306 ret = call_read_iter(file, &aio_cmd->iocb, &iter);
307
308 if (ret != -EIOCBQUEUED)
309 cmd_rw_aio_complete(&aio_cmd->iocb, ret);
310
311 return 0;
312}
313
314static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
315 u32 block_size, struct scatterlist *sgl,
316 u32 sgl_nents, u32 data_length, int is_write)
317{
318 struct scatterlist *sg;
319 struct iov_iter iter;
320 struct bio_vec *bvec;
321 ssize_t len = 0;
322 loff_t pos = (cmd->t_task_lba * block_size);
323 int ret = 0, i;
324
325 bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
326 if (!bvec) {
327 pr_err("Unable to allocate fd_do_readv iov[]\n");
328 return -ENOMEM;
329 }
330
331 for_each_sg(sgl, sg, sgl_nents, i) {
332 bvec[i].bv_page = sg_page(sg);
333 bvec[i].bv_len = sg->length;
334 bvec[i].bv_offset = sg->offset;
335
336 len += sg->length;
337 }
338
339 iov_iter_bvec(&iter, is_write, bvec, sgl_nents, len);
340 if (is_write)
341 ret = vfs_iter_write(fd, &iter, &pos, 0);
342 else
343 ret = vfs_iter_read(fd, &iter, &pos, 0);
344
345 if (is_write) {
346 if (ret < 0 || ret != data_length) {
347 pr_err("%s() write returned %d\n", __func__, ret);
348 if (ret >= 0)
349 ret = -EINVAL;
350 }
351 } else {
352 /*
353 * Return zeros and GOOD status even if the READ did not return
354 * the expected virt_size for struct file w/o a backing struct
355 * block_device.
356 */
357 if (S_ISBLK(file_inode(fd)->i_mode)) {
358 if (ret < 0 || ret != data_length) {
359 pr_err("%s() returned %d, expecting %u for "
360 "S_ISBLK\n", __func__, ret,
361 data_length);
362 if (ret >= 0)
363 ret = -EINVAL;
364 }
365 } else {
366 if (ret < 0) {
367 pr_err("%s() returned %d for non S_ISBLK\n",
368 __func__, ret);
369 } else if (ret != data_length) {
370 /*
371 * Short read case:
372 * Probably some one truncate file under us.
373 * We must explicitly zero sg-pages to prevent
374 * expose uninizialized pages to userspace.
375 */
376 if (ret < data_length)
377 ret += iov_iter_zero(data_length - ret, &iter);
378 else
379 ret = -EINVAL;
380 }
381 }
382 }
383 kfree(bvec);
384 return ret;
385}
386
387static sense_reason_t
388fd_execute_sync_cache(struct se_cmd *cmd)
389{
390 struct se_device *dev = cmd->se_dev;
391 struct fd_dev *fd_dev = FD_DEV(dev);
392 int immed = (cmd->t_task_cdb[1] & 0x2);
393 loff_t start, end;
394 int ret;
395
396 /*
397 * If the Immediate bit is set, queue up the GOOD response
398 * for this SYNCHRONIZE_CACHE op
399 */
400 if (immed)
401 target_complete_cmd(cmd, SAM_STAT_GOOD);
402
403 /*
404 * Determine if we will be flushing the entire device.
405 */
406 if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
407 start = 0;
408 end = LLONG_MAX;
409 } else {
410 start = cmd->t_task_lba * dev->dev_attrib.block_size;
411 if (cmd->data_length)
412 end = start + cmd->data_length - 1;
413 else
414 end = LLONG_MAX;
415 }
416
417 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
418 if (ret != 0)
419 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
420
421 if (immed)
422 return 0;
423
424 if (ret)
425 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
426 else
427 target_complete_cmd(cmd, SAM_STAT_GOOD);
428
429 return 0;
430}
431
432static sense_reason_t
433fd_execute_write_same(struct se_cmd *cmd)
434{
435 struct se_device *se_dev = cmd->se_dev;
436 struct fd_dev *fd_dev = FD_DEV(se_dev);
437 loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
438 sector_t nolb = sbc_get_write_same_sectors(cmd);
439 struct iov_iter iter;
440 struct bio_vec *bvec;
441 unsigned int len = 0, i;
442 ssize_t ret;
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)
451 return TCM_INVALID_CDB_FIELD;
452
453 if (cmd->t_data_nents > 1 ||
454 cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
455 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
456 " block_size: %u\n",
457 cmd->t_data_nents,
458 cmd->t_data_sg[0].length,
459 cmd->se_dev->dev_attrib.block_size);
460 return TCM_INVALID_CDB_FIELD;
461 }
462
463 bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
464 if (!bvec)
465 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
466
467 for (i = 0; i < nolb; i++) {
468 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
469 bvec[i].bv_len = cmd->t_data_sg[0].length;
470 bvec[i].bv_offset = cmd->t_data_sg[0].offset;
471
472 len += se_dev->dev_attrib.block_size;
473 }
474
475 iov_iter_bvec(&iter, ITER_SOURCE, bvec, nolb, len);
476 ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0);
477
478 kfree(bvec);
479 if (ret < 0 || ret != len) {
480 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
481 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
482 }
483
484 target_complete_cmd(cmd, SAM_STAT_GOOD);
485 return 0;
486}
487
488static int
489fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
490 void *buf, size_t bufsize)
491{
492 struct fd_dev *fd_dev = FD_DEV(se_dev);
493 struct file *prot_fd = fd_dev->fd_prot_file;
494 sector_t prot_length, prot;
495 loff_t pos = lba * se_dev->prot_length;
496
497 if (!prot_fd) {
498 pr_err("Unable to locate fd_dev->fd_prot_file\n");
499 return -ENODEV;
500 }
501
502 prot_length = nolb * se_dev->prot_length;
503
504 memset(buf, 0xff, bufsize);
505 for (prot = 0; prot < prot_length;) {
506 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
507 ssize_t ret = kernel_write(prot_fd, buf, len, &pos);
508
509 if (ret != len) {
510 pr_err("vfs_write to prot file failed: %zd\n", ret);
511 return ret < 0 ? ret : -ENODEV;
512 }
513 prot += ret;
514 }
515
516 return 0;
517}
518
519static int
520fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
521{
522 void *buf;
523 int rc;
524
525 buf = (void *)__get_free_page(GFP_KERNEL);
526 if (!buf) {
527 pr_err("Unable to allocate FILEIO prot buf\n");
528 return -ENOMEM;
529 }
530
531 rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
532
533 free_page((unsigned long)buf);
534
535 return rc;
536}
537
538static sense_reason_t
539fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
540{
541 struct file *file = FD_DEV(cmd->se_dev)->fd_file;
542 struct inode *inode = file->f_mapping->host;
543 int ret;
544
545 if (!nolb) {
546 return 0;
547 }
548
549 if (cmd->se_dev->dev_attrib.pi_prot_type) {
550 ret = fd_do_prot_unmap(cmd, lba, nolb);
551 if (ret)
552 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
553 }
554
555 if (S_ISBLK(inode->i_mode)) {
556 /* The backend is block device, use discard */
557 struct block_device *bdev = I_BDEV(inode);
558 struct se_device *dev = cmd->se_dev;
559
560 ret = blkdev_issue_discard(bdev,
561 target_to_linux_sector(dev, lba),
562 target_to_linux_sector(dev, nolb),
563 GFP_KERNEL);
564 if (ret < 0) {
565 pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
566 ret);
567 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
568 }
569 } else {
570 /* The backend is normal file, use fallocate */
571 struct se_device *se_dev = cmd->se_dev;
572 loff_t pos = lba * se_dev->dev_attrib.block_size;
573 unsigned int len = nolb * se_dev->dev_attrib.block_size;
574 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
575
576 if (!file->f_op->fallocate)
577 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
578
579 ret = file->f_op->fallocate(file, mode, pos, len);
580 if (ret < 0) {
581 pr_warn("FILEIO: fallocate() failed: %d\n", ret);
582 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
583 }
584 }
585
586 return 0;
587}
588
589static sense_reason_t
590fd_execute_rw_buffered(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
591 enum dma_data_direction data_direction)
592{
593 struct se_device *dev = cmd->se_dev;
594 struct fd_dev *fd_dev = FD_DEV(dev);
595 struct file *file = fd_dev->fd_file;
596 struct file *pfile = fd_dev->fd_prot_file;
597 sense_reason_t rc;
598 int ret = 0;
599 /*
600 * Call vectorized fileio functions to map struct scatterlist
601 * physical memory addresses to struct iovec virtual memory.
602 */
603 if (data_direction == DMA_FROM_DEVICE) {
604 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
605 ret = fd_do_rw(cmd, pfile, dev->prot_length,
606 cmd->t_prot_sg, cmd->t_prot_nents,
607 cmd->prot_length, 0);
608 if (ret < 0)
609 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
610 }
611
612 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
613 sgl, sgl_nents, cmd->data_length, 0);
614
615 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type &&
616 dev->dev_attrib.pi_prot_verify) {
617 u32 sectors = cmd->data_length >>
618 ilog2(dev->dev_attrib.block_size);
619
620 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
621 0, cmd->t_prot_sg, 0);
622 if (rc)
623 return rc;
624 }
625 } else {
626 if (cmd->prot_type && dev->dev_attrib.pi_prot_type &&
627 dev->dev_attrib.pi_prot_verify) {
628 u32 sectors = cmd->data_length >>
629 ilog2(dev->dev_attrib.block_size);
630
631 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
632 0, cmd->t_prot_sg, 0);
633 if (rc)
634 return rc;
635 }
636
637 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
638 sgl, sgl_nents, cmd->data_length, 1);
639 /*
640 * Perform implicit vfs_fsync_range() for fd_do_writev() ops
641 * for SCSI WRITEs with Forced Unit Access (FUA) set.
642 * Allow this to happen independent of WCE=0 setting.
643 */
644 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
645 loff_t start = cmd->t_task_lba *
646 dev->dev_attrib.block_size;
647 loff_t end;
648
649 if (cmd->data_length)
650 end = start + cmd->data_length - 1;
651 else
652 end = LLONG_MAX;
653
654 vfs_fsync_range(fd_dev->fd_file, start, end, 1);
655 }
656
657 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
658 ret = fd_do_rw(cmd, pfile, dev->prot_length,
659 cmd->t_prot_sg, cmd->t_prot_nents,
660 cmd->prot_length, 1);
661 if (ret < 0)
662 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
663 }
664 }
665
666 if (ret < 0)
667 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
668
669 target_complete_cmd(cmd, SAM_STAT_GOOD);
670 return 0;
671}
672
673static sense_reason_t
674fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
675 enum dma_data_direction data_direction)
676{
677 struct se_device *dev = cmd->se_dev;
678 struct fd_dev *fd_dev = FD_DEV(dev);
679
680 /*
681 * We are currently limited by the number of iovecs (2048) per
682 * single vfs_[writev,readv] call.
683 */
684 if (cmd->data_length > FD_MAX_BYTES) {
685 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
686 "FD_MAX_BYTES: %u iovec count limitation\n",
687 cmd->data_length, FD_MAX_BYTES);
688 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
689 }
690
691 if (fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO)
692 return fd_execute_rw_aio(cmd, sgl, sgl_nents, data_direction);
693 return fd_execute_rw_buffered(cmd, sgl, sgl_nents, data_direction);
694}
695
696enum {
697 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io,
698 Opt_fd_async_io, Opt_err
699};
700
701static match_table_t tokens = {
702 {Opt_fd_dev_name, "fd_dev_name=%s"},
703 {Opt_fd_dev_size, "fd_dev_size=%s"},
704 {Opt_fd_buffered_io, "fd_buffered_io=%d"},
705 {Opt_fd_async_io, "fd_async_io=%d"},
706 {Opt_err, NULL}
707};
708
709static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
710 const char *page, ssize_t count)
711{
712 struct fd_dev *fd_dev = FD_DEV(dev);
713 char *orig, *ptr, *arg_p, *opts;
714 substring_t args[MAX_OPT_ARGS];
715 int ret = 0, arg, token;
716
717 opts = kstrdup(page, GFP_KERNEL);
718 if (!opts)
719 return -ENOMEM;
720
721 orig = opts;
722
723 while ((ptr = strsep(&opts, ",\n")) != NULL) {
724 if (!*ptr)
725 continue;
726
727 token = match_token(ptr, tokens, args);
728 switch (token) {
729 case Opt_fd_dev_name:
730 if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
731 FD_MAX_DEV_NAME) == 0) {
732 ret = -EINVAL;
733 break;
734 }
735 pr_debug("FILEIO: Referencing Path: %s\n",
736 fd_dev->fd_dev_name);
737 fd_dev->fbd_flags |= FBDF_HAS_PATH;
738 break;
739 case Opt_fd_dev_size:
740 arg_p = match_strdup(&args[0]);
741 if (!arg_p) {
742 ret = -ENOMEM;
743 break;
744 }
745 ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
746 kfree(arg_p);
747 if (ret < 0) {
748 pr_err("kstrtoull() failed for"
749 " fd_dev_size=\n");
750 goto out;
751 }
752 pr_debug("FILEIO: Referencing Size: %llu"
753 " bytes\n", fd_dev->fd_dev_size);
754 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
755 break;
756 case Opt_fd_buffered_io:
757 ret = match_int(args, &arg);
758 if (ret)
759 goto out;
760 if (arg != 1) {
761 pr_err("bogus fd_buffered_io=%d value\n", arg);
762 ret = -EINVAL;
763 goto out;
764 }
765
766 pr_debug("FILEIO: Using buffered I/O"
767 " operations for struct fd_dev\n");
768
769 fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
770 break;
771 case Opt_fd_async_io:
772 ret = match_int(args, &arg);
773 if (ret)
774 goto out;
775 if (arg != 1) {
776 pr_err("bogus fd_async_io=%d value\n", arg);
777 ret = -EINVAL;
778 goto out;
779 }
780
781 pr_debug("FILEIO: Using async I/O"
782 " operations for struct fd_dev\n");
783
784 fd_dev->fbd_flags |= FDBD_HAS_ASYNC_IO;
785 break;
786 default:
787 break;
788 }
789 }
790
791out:
792 kfree(orig);
793 return (!ret) ? count : ret;
794}
795
796static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
797{
798 struct fd_dev *fd_dev = FD_DEV(dev);
799 ssize_t bl = 0;
800
801 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
802 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s Async: %d\n",
803 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
804 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
805 "Buffered-WCE" : "O_DSYNC",
806 !!(fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO));
807 return bl;
808}
809
810static sector_t fd_get_blocks(struct se_device *dev)
811{
812 struct fd_dev *fd_dev = FD_DEV(dev);
813 struct file *f = fd_dev->fd_file;
814 struct inode *i = f->f_mapping->host;
815 unsigned long long dev_size;
816 /*
817 * When using a file that references an underlying struct block_device,
818 * ensure dev_size is always based on the current inode size in order
819 * to handle underlying block_device resize operations.
820 */
821 if (S_ISBLK(i->i_mode))
822 dev_size = i_size_read(i);
823 else
824 dev_size = fd_dev->fd_dev_size;
825
826 return div_u64(dev_size - dev->dev_attrib.block_size,
827 dev->dev_attrib.block_size);
828}
829
830static int fd_init_prot(struct se_device *dev)
831{
832 struct fd_dev *fd_dev = FD_DEV(dev);
833 struct file *prot_file, *file = fd_dev->fd_file;
834 struct inode *inode;
835 int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
836 char buf[FD_MAX_DEV_PROT_NAME];
837
838 if (!file) {
839 pr_err("Unable to locate fd_dev->fd_file\n");
840 return -ENODEV;
841 }
842
843 inode = file->f_mapping->host;
844 if (S_ISBLK(inode->i_mode)) {
845 pr_err("FILEIO Protection emulation only supported on"
846 " !S_ISBLK\n");
847 return -ENOSYS;
848 }
849
850 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
851 flags &= ~O_DSYNC;
852
853 snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
854 fd_dev->fd_dev_name);
855
856 prot_file = filp_open(buf, flags, 0600);
857 if (IS_ERR(prot_file)) {
858 pr_err("filp_open(%s) failed\n", buf);
859 ret = PTR_ERR(prot_file);
860 return ret;
861 }
862 fd_dev->fd_prot_file = prot_file;
863
864 return 0;
865}
866
867static int fd_format_prot(struct se_device *dev)
868{
869 unsigned char *buf;
870 int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
871 int ret;
872
873 if (!dev->dev_attrib.pi_prot_type) {
874 pr_err("Unable to format_prot while pi_prot_type == 0\n");
875 return -ENODEV;
876 }
877
878 buf = vzalloc(unit_size);
879 if (!buf) {
880 pr_err("Unable to allocate FILEIO prot buf\n");
881 return -ENOMEM;
882 }
883
884 pr_debug("Using FILEIO prot_length: %llu\n",
885 (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
886 dev->prot_length);
887
888 ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
889 buf, unit_size);
890 vfree(buf);
891 return ret;
892}
893
894static void fd_free_prot(struct se_device *dev)
895{
896 struct fd_dev *fd_dev = FD_DEV(dev);
897
898 if (!fd_dev->fd_prot_file)
899 return;
900
901 filp_close(fd_dev->fd_prot_file, NULL);
902 fd_dev->fd_prot_file = NULL;
903}
904
905static struct sbc_ops fd_sbc_ops = {
906 .execute_rw = fd_execute_rw,
907 .execute_sync_cache = fd_execute_sync_cache,
908 .execute_write_same = fd_execute_write_same,
909 .execute_unmap = fd_execute_unmap,
910};
911
912static sense_reason_t
913fd_parse_cdb(struct se_cmd *cmd)
914{
915 return sbc_parse_cdb(cmd, &fd_sbc_ops);
916}
917
918static const struct target_backend_ops fileio_ops = {
919 .name = "fileio",
920 .inquiry_prod = "FILEIO",
921 .inquiry_rev = FD_VERSION,
922 .owner = THIS_MODULE,
923 .attach_hba = fd_attach_hba,
924 .detach_hba = fd_detach_hba,
925 .alloc_device = fd_alloc_device,
926 .configure_device = fd_configure_device,
927 .destroy_device = fd_destroy_device,
928 .free_device = fd_free_device,
929 .configure_unmap = fd_configure_unmap,
930 .parse_cdb = fd_parse_cdb,
931 .set_configfs_dev_params = fd_set_configfs_dev_params,
932 .show_configfs_dev_params = fd_show_configfs_dev_params,
933 .get_device_type = sbc_get_device_type,
934 .get_blocks = fd_get_blocks,
935 .init_prot = fd_init_prot,
936 .format_prot = fd_format_prot,
937 .free_prot = fd_free_prot,
938 .tb_dev_attrib_attrs = sbc_attrib_attrs,
939};
940
941static int __init fileio_module_init(void)
942{
943 return transport_backend_register(&fileio_ops);
944}
945
946static void __exit fileio_module_exit(void)
947{
948 target_backend_unregister(&fileio_ops);
949}
950
951MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
952MODULE_AUTHOR("nab@Linux-iSCSI.org");
953MODULE_LICENSE("GPL");
954
955module_init(fileio_module_init);
956module_exit(fileio_module_exit);