target: make the ->get_cdb method optional
[pandora-kernel.git] / drivers / target / target_core_file.c
1 /*******************************************************************************
2  * Filename:  target_core_file.c
3  *
4  * This file contains the Storage Engine <-> FILEIO transport specific functions
5  *
6  * Copyright (c) 2005 PyX Technologies, Inc.
7  * Copyright (c) 2005-2006 SBE, Inc.  All Rights Reserved.
8  * Copyright (c) 2007-2010 Rising Tide Systems
9  * Copyright (c) 2008-2010 Linux-iSCSI.org
10  *
11  * Nicholas A. Bellinger <nab@kernel.org>
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26  *
27  ******************************************************************************/
28
29 #include <linux/string.h>
30 #include <linux/parser.h>
31 #include <linux/timer.h>
32 #include <linux/blkdev.h>
33 #include <linux/slab.h>
34 #include <linux/spinlock.h>
35 #include <scsi/scsi.h>
36 #include <scsi/scsi_host.h>
37
38 #include <target/target_core_base.h>
39 #include <target/target_core_device.h>
40 #include <target/target_core_transport.h>
41
42 #include "target_core_file.h"
43
44 static struct se_subsystem_api fileio_template;
45
46 /*      fd_attach_hba(): (Part of se_subsystem_api_t template)
47  *
48  *
49  */
50 static int fd_attach_hba(struct se_hba *hba, u32 host_id)
51 {
52         struct fd_host *fd_host;
53
54         fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
55         if (!fd_host) {
56                 pr_err("Unable to allocate memory for struct fd_host\n");
57                 return -ENOMEM;
58         }
59
60         fd_host->fd_host_id = host_id;
61
62         hba->hba_ptr = fd_host;
63
64         pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
65                 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
66                 TARGET_CORE_MOD_VERSION);
67         pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic"
68                 " MaxSectors: %u\n",
69                 hba->hba_id, fd_host->fd_host_id, FD_MAX_SECTORS);
70
71         return 0;
72 }
73
74 static void fd_detach_hba(struct se_hba *hba)
75 {
76         struct fd_host *fd_host = hba->hba_ptr;
77
78         pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
79                 " Target Core\n", hba->hba_id, fd_host->fd_host_id);
80
81         kfree(fd_host);
82         hba->hba_ptr = NULL;
83 }
84
85 static void *fd_allocate_virtdevice(struct se_hba *hba, const char *name)
86 {
87         struct fd_dev *fd_dev;
88         struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr;
89
90         fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
91         if (!fd_dev) {
92                 pr_err("Unable to allocate memory for struct fd_dev\n");
93                 return NULL;
94         }
95
96         fd_dev->fd_host = fd_host;
97
98         pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
99
100         return fd_dev;
101 }
102
103 /*      fd_create_virtdevice(): (Part of se_subsystem_api_t template)
104  *
105  *
106  */
107 static struct se_device *fd_create_virtdevice(
108         struct se_hba *hba,
109         struct se_subsystem_dev *se_dev,
110         void *p)
111 {
112         char *dev_p = NULL;
113         struct se_device *dev;
114         struct se_dev_limits dev_limits;
115         struct queue_limits *limits;
116         struct fd_dev *fd_dev = (struct fd_dev *) p;
117         struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr;
118         mm_segment_t old_fs;
119         struct file *file;
120         struct inode *inode = NULL;
121         int dev_flags = 0, flags, ret = -EINVAL;
122
123         memset(&dev_limits, 0, sizeof(struct se_dev_limits));
124
125         old_fs = get_fs();
126         set_fs(get_ds());
127         dev_p = getname(fd_dev->fd_dev_name);
128         set_fs(old_fs);
129
130         if (IS_ERR(dev_p)) {
131                 pr_err("getname(%s) failed: %lu\n",
132                         fd_dev->fd_dev_name, IS_ERR(dev_p));
133                 ret = PTR_ERR(dev_p);
134                 goto fail;
135         }
136 #if 0
137         if (di->no_create_file)
138                 flags = O_RDWR | O_LARGEFILE;
139         else
140                 flags = O_RDWR | O_CREAT | O_LARGEFILE;
141 #else
142         flags = O_RDWR | O_CREAT | O_LARGEFILE;
143 #endif
144 /*      flags |= O_DIRECT; */
145         /*
146          * If fd_buffered_io=1 has not been set explicitly (the default),
147          * use O_SYNC to force FILEIO writes to disk.
148          */
149         if (!(fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO))
150                 flags |= O_SYNC;
151
152         file = filp_open(dev_p, flags, 0600);
153         if (IS_ERR(file)) {
154                 pr_err("filp_open(%s) failed\n", dev_p);
155                 ret = PTR_ERR(file);
156                 goto fail;
157         }
158         if (!file || !file->f_dentry) {
159                 pr_err("filp_open(%s) failed\n", dev_p);
160                 goto fail;
161         }
162         fd_dev->fd_file = file;
163         /*
164          * If using a block backend with this struct file, we extract
165          * fd_dev->fd_[block,dev]_size from struct block_device.
166          *
167          * Otherwise, we use the passed fd_size= from configfs
168          */
169         inode = file->f_mapping->host;
170         if (S_ISBLK(inode->i_mode)) {
171                 struct request_queue *q;
172                 /*
173                  * Setup the local scope queue_limits from struct request_queue->limits
174                  * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
175                  */
176                 q = bdev_get_queue(inode->i_bdev);
177                 limits = &dev_limits.limits;
178                 limits->logical_block_size = bdev_logical_block_size(inode->i_bdev);
179                 limits->max_hw_sectors = queue_max_hw_sectors(q);
180                 limits->max_sectors = queue_max_sectors(q);
181                 /*
182                  * Determine the number of bytes from i_size_read() minus
183                  * one (1) logical sector from underlying struct block_device
184                  */
185                 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
186                 fd_dev->fd_dev_size = (i_size_read(file->f_mapping->host) -
187                                        fd_dev->fd_block_size);
188
189                 pr_debug("FILEIO: Using size: %llu bytes from struct"
190                         " block_device blocks: %llu logical_block_size: %d\n",
191                         fd_dev->fd_dev_size,
192                         div_u64(fd_dev->fd_dev_size, fd_dev->fd_block_size),
193                         fd_dev->fd_block_size);
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                 limits = &dev_limits.limits;
203                 limits->logical_block_size = FD_BLOCKSIZE;
204                 limits->max_hw_sectors = FD_MAX_SECTORS;
205                 limits->max_sectors = FD_MAX_SECTORS;
206                 fd_dev->fd_block_size = FD_BLOCKSIZE;
207         }
208
209         dev_limits.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
210         dev_limits.queue_depth = FD_DEVICE_QUEUE_DEPTH;
211
212         dev = transport_add_device_to_core_hba(hba, &fileio_template,
213                                 se_dev, dev_flags, fd_dev,
214                                 &dev_limits, "FILEIO", FD_VERSION);
215         if (!dev)
216                 goto fail;
217
218         fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
219         fd_dev->fd_queue_depth = dev->queue_depth;
220
221         pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
222                 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
223                         fd_dev->fd_dev_name, fd_dev->fd_dev_size);
224
225         putname(dev_p);
226         return dev;
227 fail:
228         if (fd_dev->fd_file) {
229                 filp_close(fd_dev->fd_file, NULL);
230                 fd_dev->fd_file = NULL;
231         }
232         putname(dev_p);
233         return ERR_PTR(ret);
234 }
235
236 /*      fd_free_device(): (Part of se_subsystem_api_t template)
237  *
238  *
239  */
240 static void fd_free_device(void *p)
241 {
242         struct fd_dev *fd_dev = (struct fd_dev *) p;
243
244         if (fd_dev->fd_file) {
245                 filp_close(fd_dev->fd_file, NULL);
246                 fd_dev->fd_file = NULL;
247         }
248
249         kfree(fd_dev);
250 }
251
252 static inline struct fd_request *FILE_REQ(struct se_task *task)
253 {
254         return container_of(task, struct fd_request, fd_task);
255 }
256
257
258 static struct se_task *
259 fd_alloc_task(unsigned char *cdb)
260 {
261         struct fd_request *fd_req;
262
263         fd_req = kzalloc(sizeof(struct fd_request), GFP_KERNEL);
264         if (!fd_req) {
265                 pr_err("Unable to allocate struct fd_request\n");
266                 return NULL;
267         }
268
269         return &fd_req->fd_task;
270 }
271
272 static int fd_do_readv(struct se_task *task)
273 {
274         struct fd_request *req = FILE_REQ(task);
275         struct se_device *se_dev = req->fd_task.task_se_cmd->se_dev;
276         struct fd_dev *dev = 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                       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
325 static int fd_do_writev(struct se_task *task)
326 {
327         struct fd_request *req = FILE_REQ(task);
328         struct se_device *se_dev = req->fd_task.task_se_cmd->se_dev;
329         struct fd_dev *dev = se_dev->dev_ptr;
330         struct file *fd = dev->fd_file;
331         struct scatterlist *sg = task->task_sg;
332         struct iovec *iov;
333         mm_segment_t old_fs;
334         loff_t pos = (task->task_lba *
335                       se_dev->se_sub_dev->se_dev_attrib.block_size);
336         int ret, i = 0;
337
338         iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL);
339         if (!iov) {
340                 pr_err("Unable to allocate fd_do_writev iov[]\n");
341                 return -ENOMEM;
342         }
343
344         for (i = 0; i < task->task_sg_nents; i++) {
345                 iov[i].iov_len = sg[i].length;
346                 iov[i].iov_base = sg_virt(&sg[i]);
347         }
348
349         old_fs = get_fs();
350         set_fs(get_ds());
351         ret = vfs_writev(fd, &iov[0], task->task_sg_nents, &pos);
352         set_fs(old_fs);
353
354         kfree(iov);
355
356         if (ret < 0 || ret != task->task_size) {
357                 pr_err("vfs_writev() returned %d\n", ret);
358                 return (ret < 0 ? ret : -EINVAL);
359         }
360
361         return 1;
362 }
363
364 static void fd_emulate_sync_cache(struct se_task *task)
365 {
366         struct se_cmd *cmd = task->task_se_cmd;
367         struct se_device *dev = cmd->se_dev;
368         struct fd_dev *fd_dev = dev->dev_ptr;
369         int immed = (cmd->t_task_cdb[1] & 0x2);
370         loff_t start, end;
371         int ret;
372
373         /*
374          * If the Immediate bit is set, queue up the GOOD response
375          * for this SYNCHRONIZE_CACHE op
376          */
377         if (immed)
378                 transport_complete_sync_cache(cmd, 1);
379
380         /*
381          * Determine if we will be flushing the entire device.
382          */
383         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
384                 start = 0;
385                 end = LLONG_MAX;
386         } else {
387                 start = cmd->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
388                 if (cmd->data_length)
389                         end = start + cmd->data_length;
390                 else
391                         end = LLONG_MAX;
392         }
393
394         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
395         if (ret != 0)
396                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
397
398         if (!immed)
399                 transport_complete_sync_cache(cmd, ret == 0);
400 }
401
402 /*
403  * Tell TCM Core that we are capable of WriteCache emulation for
404  * an underlying struct se_device.
405  */
406 static int fd_emulated_write_cache(struct se_device *dev)
407 {
408         return 1;
409 }
410
411 static int fd_emulated_dpo(struct se_device *dev)
412 {
413         return 0;
414 }
415 /*
416  * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs
417  * for TYPE_DISK.
418  */
419 static int fd_emulated_fua_write(struct se_device *dev)
420 {
421         return 1;
422 }
423
424 static int fd_emulated_fua_read(struct se_device *dev)
425 {
426         return 0;
427 }
428
429 /*
430  * WRITE Force Unit Access (FUA) emulation on a per struct se_task
431  * LBA range basis..
432  */
433 static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task)
434 {
435         struct se_device *dev = cmd->se_dev;
436         struct fd_dev *fd_dev = dev->dev_ptr;
437         loff_t start = task->task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
438         loff_t end = start + task->task_size;
439         int ret;
440
441         pr_debug("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n",
442                         task->task_lba, task->task_size);
443
444         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
445         if (ret != 0)
446                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
447 }
448
449 static int fd_do_task(struct se_task *task)
450 {
451         struct se_cmd *cmd = task->task_se_cmd;
452         struct se_device *dev = cmd->se_dev;
453         int ret = 0;
454
455         /*
456          * Call vectorized fileio functions to map struct scatterlist
457          * physical memory addresses to struct iovec virtual memory.
458          */
459         if (task->task_data_direction == DMA_FROM_DEVICE) {
460                 ret = fd_do_readv(task);
461         } else {
462                 ret = fd_do_writev(task);
463
464                 if (ret > 0 &&
465                     dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0 &&
466                     dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
467                     cmd->t_tasks_fua) {
468                         /*
469                          * We might need to be a bit smarter here
470                          * and return some sense data to let the initiator
471                          * know the FUA WRITE cache sync failed..?
472                          */
473                         fd_emulate_write_fua(cmd, task);
474                 }
475
476         }
477
478         if (ret < 0)
479                 return ret;
480         if (ret) {
481                 task->task_scsi_status = GOOD;
482                 transport_complete_task(task, 1);
483         }
484         return PYX_TRANSPORT_SENT_TO_TRANSPORT;
485 }
486
487 /*      fd_free_task(): (Part of se_subsystem_api_t template)
488  *
489  *
490  */
491 static void fd_free_task(struct se_task *task)
492 {
493         struct fd_request *req = FILE_REQ(task);
494
495         kfree(req);
496 }
497
498 enum {
499         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
500 };
501
502 static match_table_t tokens = {
503         {Opt_fd_dev_name, "fd_dev_name=%s"},
504         {Opt_fd_dev_size, "fd_dev_size=%s"},
505         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
506         {Opt_err, NULL}
507 };
508
509 static ssize_t fd_set_configfs_dev_params(
510         struct se_hba *hba,
511         struct se_subsystem_dev *se_dev,
512         const char *page, ssize_t count)
513 {
514         struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
515         char *orig, *ptr, *arg_p, *opts;
516         substring_t args[MAX_OPT_ARGS];
517         int ret = 0, arg, token;
518
519         opts = kstrdup(page, GFP_KERNEL);
520         if (!opts)
521                 return -ENOMEM;
522
523         orig = opts;
524
525         while ((ptr = strsep(&opts, ",")) != NULL) {
526                 if (!*ptr)
527                         continue;
528
529                 token = match_token(ptr, tokens, args);
530                 switch (token) {
531                 case Opt_fd_dev_name:
532                         arg_p = match_strdup(&args[0]);
533                         if (!arg_p) {
534                                 ret = -ENOMEM;
535                                 break;
536                         }
537                         snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME,
538                                         "%s", arg_p);
539                         kfree(arg_p);
540                         pr_debug("FILEIO: Referencing Path: %s\n",
541                                         fd_dev->fd_dev_name);
542                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
543                         break;
544                 case Opt_fd_dev_size:
545                         arg_p = match_strdup(&args[0]);
546                         if (!arg_p) {
547                                 ret = -ENOMEM;
548                                 break;
549                         }
550                         ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size);
551                         kfree(arg_p);
552                         if (ret < 0) {
553                                 pr_err("strict_strtoull() failed for"
554                                                 " fd_dev_size=\n");
555                                 goto out;
556                         }
557                         pr_debug("FILEIO: Referencing Size: %llu"
558                                         " bytes\n", fd_dev->fd_dev_size);
559                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
560                         break;
561                 case Opt_fd_buffered_io:
562                         match_int(args, &arg);
563                         if (arg != 1) {
564                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
565                                 ret = -EINVAL;
566                                 goto out;
567                         }
568
569                         pr_debug("FILEIO: Using buffered I/O"
570                                 " operations for struct fd_dev\n");
571
572                         fd_dev->fbd_flags |= FDBD_USE_BUFFERED_IO;
573                         break;
574                 default:
575                         break;
576                 }
577         }
578
579 out:
580         kfree(orig);
581         return (!ret) ? count : ret;
582 }
583
584 static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev)
585 {
586         struct fd_dev *fd_dev = (struct fd_dev *) se_dev->se_dev_su_ptr;
587
588         if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
589                 pr_err("Missing fd_dev_name=\n");
590                 return -EINVAL;
591         }
592
593         return 0;
594 }
595
596 static ssize_t fd_show_configfs_dev_params(
597         struct se_hba *hba,
598         struct se_subsystem_dev *se_dev,
599         char *b)
600 {
601         struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
602         ssize_t bl = 0;
603
604         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
605         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
606                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
607                 (fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO) ?
608                 "Buffered" : "Synchronous");
609         return bl;
610 }
611
612 /*      fd_get_device_rev(): (Part of se_subsystem_api_t template)
613  *
614  *
615  */
616 static u32 fd_get_device_rev(struct se_device *dev)
617 {
618         return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
619 }
620
621 /*      fd_get_device_type(): (Part of se_subsystem_api_t template)
622  *
623  *
624  */
625 static u32 fd_get_device_type(struct se_device *dev)
626 {
627         return TYPE_DISK;
628 }
629
630 static sector_t fd_get_blocks(struct se_device *dev)
631 {
632         struct fd_dev *fd_dev = dev->dev_ptr;
633         unsigned long long blocks_long = div_u64(fd_dev->fd_dev_size,
634                         dev->se_sub_dev->se_dev_attrib.block_size);
635
636         return blocks_long;
637 }
638
639 static struct se_subsystem_api fileio_template = {
640         .name                   = "fileio",
641         .owner                  = THIS_MODULE,
642         .transport_type         = TRANSPORT_PLUGIN_VHBA_PDEV,
643         .attach_hba             = fd_attach_hba,
644         .detach_hba             = fd_detach_hba,
645         .allocate_virtdevice    = fd_allocate_virtdevice,
646         .create_virtdevice      = fd_create_virtdevice,
647         .free_device            = fd_free_device,
648         .dpo_emulated           = fd_emulated_dpo,
649         .fua_write_emulated     = fd_emulated_fua_write,
650         .fua_read_emulated      = fd_emulated_fua_read,
651         .write_cache_emulated   = fd_emulated_write_cache,
652         .alloc_task             = fd_alloc_task,
653         .do_task                = fd_do_task,
654         .do_sync_cache          = fd_emulate_sync_cache,
655         .free_task              = fd_free_task,
656         .check_configfs_dev_params = fd_check_configfs_dev_params,
657         .set_configfs_dev_params = fd_set_configfs_dev_params,
658         .show_configfs_dev_params = fd_show_configfs_dev_params,
659         .get_device_rev         = fd_get_device_rev,
660         .get_device_type        = fd_get_device_type,
661         .get_blocks             = fd_get_blocks,
662 };
663
664 static int __init fileio_module_init(void)
665 {
666         return transport_subsystem_register(&fileio_template);
667 }
668
669 static void fileio_module_exit(void)
670 {
671         transport_subsystem_release(&fileio_template);
672 }
673
674 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
675 MODULE_AUTHOR("nab@Linux-iSCSI.org");
676 MODULE_LICENSE("GPL");
677
678 module_init(fileio_module_init);
679 module_exit(fileio_module_exit);