1 /*******************************************************************************
2 * Filename: target_core_file.c
4 * This file contains the Storage Engine <-> FILEIO transport specific functions
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
11 * Nicholas A. Bellinger <nab@kernel.org>
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.
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.
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.
27 ******************************************************************************/
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 <linux/module.h>
36 #include <scsi/scsi.h>
37 #include <scsi/scsi_host.h>
39 #include <target/target_core_base.h>
40 #include <target/target_core_backend.h>
42 #include "target_core_file.h"
44 static struct se_subsystem_api fileio_template
;
46 /* fd_attach_hba(): (Part of se_subsystem_api_t template)
50 static int fd_attach_hba(struct se_hba
*hba
, u32 host_id
)
52 struct fd_host
*fd_host
;
54 fd_host
= kzalloc(sizeof(struct fd_host
), GFP_KERNEL
);
56 pr_err("Unable to allocate memory for struct fd_host\n");
60 fd_host
->fd_host_id
= host_id
;
62 hba
->hba_ptr
= fd_host
;
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"
69 hba
->hba_id
, fd_host
->fd_host_id
, FD_MAX_SECTORS
);
74 static void fd_detach_hba(struct se_hba
*hba
)
76 struct fd_host
*fd_host
= hba
->hba_ptr
;
78 pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
79 " Target Core\n", hba
->hba_id
, fd_host
->fd_host_id
);
85 static void *fd_allocate_virtdevice(struct se_hba
*hba
, const char *name
)
87 struct fd_dev
*fd_dev
;
88 struct fd_host
*fd_host
= hba
->hba_ptr
;
90 fd_dev
= kzalloc(sizeof(struct fd_dev
), GFP_KERNEL
);
92 pr_err("Unable to allocate memory for struct fd_dev\n");
96 fd_dev
->fd_host
= fd_host
;
98 pr_debug("FILEIO: Allocated fd_dev for %p\n", name
);
103 /* fd_create_virtdevice(): (Part of se_subsystem_api_t template)
107 static struct se_device
*fd_create_virtdevice(
109 struct se_subsystem_dev
*se_dev
,
112 struct se_device
*dev
;
113 struct se_dev_limits dev_limits
;
114 struct queue_limits
*limits
;
115 struct fd_dev
*fd_dev
= p
;
116 struct fd_host
*fd_host
= hba
->hba_ptr
;
118 struct inode
*inode
= NULL
;
119 int dev_flags
= 0, flags
, ret
= -EINVAL
;
121 memset(&dev_limits
, 0, sizeof(struct se_dev_limits
));
124 * Use O_DSYNC by default instead of O_SYNC to forgo syncing
125 * of pure timestamp updates.
127 flags
= O_RDWR
| O_CREAT
| O_LARGEFILE
| O_DSYNC
;
129 file
= filp_open(fd_dev
->fd_dev_name
, flags
, 0600);
131 pr_err("filp_open(%s) failed\n", fd_dev
->fd_dev_name
);
135 fd_dev
->fd_file
= file
;
137 * If using a block backend with this struct file, we extract
138 * fd_dev->fd_[block,dev]_size from struct block_device.
140 * Otherwise, we use the passed fd_size= from configfs
142 inode
= file
->f_mapping
->host
;
143 if (S_ISBLK(inode
->i_mode
)) {
144 struct request_queue
*q
;
145 unsigned long long dev_size
;
147 * Setup the local scope queue_limits from struct request_queue->limits
148 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
150 q
= bdev_get_queue(inode
->i_bdev
);
151 limits
= &dev_limits
.limits
;
152 limits
->logical_block_size
= bdev_logical_block_size(inode
->i_bdev
);
153 limits
->max_hw_sectors
= queue_max_hw_sectors(q
);
154 limits
->max_sectors
= queue_max_sectors(q
);
156 * Determine the number of bytes from i_size_read() minus
157 * one (1) logical sector from underlying struct block_device
159 fd_dev
->fd_block_size
= bdev_logical_block_size(inode
->i_bdev
);
160 dev_size
= (i_size_read(file
->f_mapping
->host
) -
161 fd_dev
->fd_block_size
);
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
);
168 if (!(fd_dev
->fbd_flags
& FBDF_HAS_SIZE
)) {
169 pr_err("FILEIO: Missing fd_dev_size="
170 " parameter, and no backing struct"
175 limits
= &dev_limits
.limits
;
176 limits
->logical_block_size
= FD_BLOCKSIZE
;
177 limits
->max_hw_sectors
= FD_MAX_SECTORS
;
178 limits
->max_sectors
= FD_MAX_SECTORS
;
179 fd_dev
->fd_block_size
= FD_BLOCKSIZE
;
182 dev_limits
.hw_queue_depth
= FD_MAX_DEVICE_QUEUE_DEPTH
;
183 dev_limits
.queue_depth
= FD_DEVICE_QUEUE_DEPTH
;
185 dev
= transport_add_device_to_core_hba(hba
, &fileio_template
,
186 se_dev
, dev_flags
, fd_dev
,
187 &dev_limits
, "FILEIO", FD_VERSION
);
191 fd_dev
->fd_dev_id
= fd_host
->fd_host_dev_id_count
++;
192 fd_dev
->fd_queue_depth
= dev
->queue_depth
;
194 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
195 " %llu total bytes\n", fd_host
->fd_host_id
, fd_dev
->fd_dev_id
,
196 fd_dev
->fd_dev_name
, fd_dev
->fd_dev_size
);
200 if (fd_dev
->fd_file
) {
201 filp_close(fd_dev
->fd_file
, NULL
);
202 fd_dev
->fd_file
= NULL
;
207 /* fd_free_device(): (Part of se_subsystem_api_t template)
211 static void fd_free_device(void *p
)
213 struct fd_dev
*fd_dev
= p
;
215 if (fd_dev
->fd_file
) {
216 filp_close(fd_dev
->fd_file
, NULL
);
217 fd_dev
->fd_file
= NULL
;
223 static int fd_do_readv(struct se_cmd
*cmd
, struct scatterlist
*sgl
,
226 struct se_device
*se_dev
= cmd
->se_dev
;
227 struct fd_dev
*dev
= se_dev
->dev_ptr
;
228 struct file
*fd
= dev
->fd_file
;
229 struct scatterlist
*sg
;
232 loff_t pos
= (cmd
->t_task_lba
*
233 se_dev
->se_sub_dev
->se_dev_attrib
.block_size
);
236 iov
= kzalloc(sizeof(struct iovec
) * sgl_nents
, GFP_KERNEL
);
238 pr_err("Unable to allocate fd_do_readv iov[]\n");
242 for_each_sg(sgl
, sg
, sgl_nents
, i
) {
243 iov
[i
].iov_len
= sg
->length
;
244 iov
[i
].iov_base
= sg_virt(sg
);
249 ret
= vfs_readv(fd
, &iov
[0], sgl_nents
, &pos
);
254 * Return zeros and GOOD status even if the READ did not return
255 * the expected virt_size for struct file w/o a backing struct
258 if (S_ISBLK(fd
->f_dentry
->d_inode
->i_mode
)) {
259 if (ret
< 0 || ret
!= cmd
->data_length
) {
260 pr_err("vfs_readv() returned %d,"
261 " expecting %d for S_ISBLK\n", ret
,
262 (int)cmd
->data_length
);
263 return (ret
< 0 ? ret
: -EINVAL
);
267 pr_err("vfs_readv() returned %d for non"
276 static int fd_do_writev(struct se_cmd
*cmd
, struct scatterlist
*sgl
,
279 struct se_device
*se_dev
= cmd
->se_dev
;
280 struct fd_dev
*dev
= se_dev
->dev_ptr
;
281 struct file
*fd
= dev
->fd_file
;
282 struct scatterlist
*sg
;
285 loff_t pos
= (cmd
->t_task_lba
*
286 se_dev
->se_sub_dev
->se_dev_attrib
.block_size
);
289 iov
= kzalloc(sizeof(struct iovec
) * sgl_nents
, GFP_KERNEL
);
291 pr_err("Unable to allocate fd_do_writev iov[]\n");
295 for_each_sg(sgl
, sg
, sgl_nents
, i
) {
296 iov
[i
].iov_len
= sg
->length
;
297 iov
[i
].iov_base
= sg_virt(sg
);
302 ret
= vfs_writev(fd
, &iov
[0], sgl_nents
, &pos
);
307 if (ret
< 0 || ret
!= cmd
->data_length
) {
308 pr_err("vfs_writev() returned %d\n", ret
);
309 return (ret
< 0 ? ret
: -EINVAL
);
315 static int fd_execute_sync_cache(struct se_cmd
*cmd
)
317 struct se_device
*dev
= cmd
->se_dev
;
318 struct fd_dev
*fd_dev
= dev
->dev_ptr
;
319 int immed
= (cmd
->t_task_cdb
[1] & 0x2);
324 * If the Immediate bit is set, queue up the GOOD response
325 * for this SYNCHRONIZE_CACHE op
328 target_complete_cmd(cmd
, SAM_STAT_GOOD
);
331 * Determine if we will be flushing the entire device.
333 if (cmd
->t_task_lba
== 0 && cmd
->data_length
== 0) {
337 start
= cmd
->t_task_lba
* dev
->se_sub_dev
->se_dev_attrib
.block_size
;
338 if (cmd
->data_length
)
339 end
= start
+ cmd
->data_length
;
344 ret
= vfs_fsync_range(fd_dev
->fd_file
, start
, end
, 1);
346 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret
);
352 cmd
->scsi_sense_reason
= TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE
;
353 target_complete_cmd(cmd
, SAM_STAT_CHECK_CONDITION
);
355 target_complete_cmd(cmd
, SAM_STAT_GOOD
);
361 static int fd_execute_rw(struct se_cmd
*cmd
)
363 struct scatterlist
*sgl
= cmd
->t_data_sg
;
364 u32 sgl_nents
= cmd
->t_data_nents
;
365 enum dma_data_direction data_direction
= cmd
->data_direction
;
366 struct se_device
*dev
= cmd
->se_dev
;
370 * Call vectorized fileio functions to map struct scatterlist
371 * physical memory addresses to struct iovec virtual memory.
373 if (data_direction
== DMA_FROM_DEVICE
) {
374 ret
= fd_do_readv(cmd
, sgl
, sgl_nents
);
376 ret
= fd_do_writev(cmd
, sgl
, sgl_nents
);
378 * Perform implict vfs_fsync_range() for fd_do_writev() ops
379 * for SCSI WRITEs with Forced Unit Access (FUA) set.
380 * Allow this to happen independent of WCE=0 setting.
383 dev
->se_sub_dev
->se_dev_attrib
.emulate_fua_write
> 0 &&
384 (cmd
->se_cmd_flags
& SCF_FUA
)) {
385 struct fd_dev
*fd_dev
= dev
->dev_ptr
;
386 loff_t start
= cmd
->t_task_lba
*
387 dev
->se_sub_dev
->se_dev_attrib
.block_size
;
388 loff_t end
= start
+ cmd
->data_length
;
390 vfs_fsync_range(fd_dev
->fd_file
, start
, end
, 1);
395 cmd
->scsi_sense_reason
= TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE
;
399 target_complete_cmd(cmd
, SAM_STAT_GOOD
);
404 Opt_fd_dev_name
, Opt_fd_dev_size
, Opt_fd_buffered_io
, Opt_err
407 static match_table_t tokens
= {
408 {Opt_fd_dev_name
, "fd_dev_name=%s"},
409 {Opt_fd_dev_size
, "fd_dev_size=%s"},
413 static ssize_t
fd_set_configfs_dev_params(
415 struct se_subsystem_dev
*se_dev
,
416 const char *page
, ssize_t count
)
418 struct fd_dev
*fd_dev
= se_dev
->se_dev_su_ptr
;
419 char *orig
, *ptr
, *arg_p
, *opts
;
420 substring_t args
[MAX_OPT_ARGS
];
423 opts
= kstrdup(page
, GFP_KERNEL
);
429 while ((ptr
= strsep(&opts
, ",\n")) != NULL
) {
433 token
= match_token(ptr
, tokens
, args
);
435 case Opt_fd_dev_name
:
436 if (match_strlcpy(fd_dev
->fd_dev_name
, &args
[0],
437 FD_MAX_DEV_NAME
) == 0) {
441 pr_debug("FILEIO: Referencing Path: %s\n",
442 fd_dev
->fd_dev_name
);
443 fd_dev
->fbd_flags
|= FBDF_HAS_PATH
;
445 case Opt_fd_dev_size
:
446 arg_p
= match_strdup(&args
[0]);
451 ret
= strict_strtoull(arg_p
, 0, &fd_dev
->fd_dev_size
);
454 pr_err("strict_strtoull() failed for"
458 pr_debug("FILEIO: Referencing Size: %llu"
459 " bytes\n", fd_dev
->fd_dev_size
);
460 fd_dev
->fbd_flags
|= FBDF_HAS_SIZE
;
469 return (!ret
) ? count
: ret
;
472 static ssize_t
fd_check_configfs_dev_params(struct se_hba
*hba
, struct se_subsystem_dev
*se_dev
)
474 struct fd_dev
*fd_dev
= se_dev
->se_dev_su_ptr
;
476 if (!(fd_dev
->fbd_flags
& FBDF_HAS_PATH
)) {
477 pr_err("Missing fd_dev_name=\n");
484 static ssize_t
fd_show_configfs_dev_params(
486 struct se_subsystem_dev
*se_dev
,
489 struct fd_dev
*fd_dev
= se_dev
->se_dev_su_ptr
;
492 bl
= sprintf(b
+ bl
, "TCM FILEIO ID: %u", fd_dev
->fd_dev_id
);
493 bl
+= sprintf(b
+ bl
, " File: %s Size: %llu Mode: O_DSYNC\n",
494 fd_dev
->fd_dev_name
, fd_dev
->fd_dev_size
);
498 /* fd_get_device_rev(): (Part of se_subsystem_api_t template)
502 static u32
fd_get_device_rev(struct se_device
*dev
)
504 return SCSI_SPC_2
; /* Returns SPC-3 in Initiator Data */
507 /* fd_get_device_type(): (Part of se_subsystem_api_t template)
511 static u32
fd_get_device_type(struct se_device
*dev
)
516 static sector_t
fd_get_blocks(struct se_device
*dev
)
518 struct fd_dev
*fd_dev
= dev
->dev_ptr
;
519 struct file
*f
= fd_dev
->fd_file
;
520 struct inode
*i
= f
->f_mapping
->host
;
521 unsigned long long dev_size
;
523 * When using a file that references an underlying struct block_device,
524 * ensure dev_size is always based on the current inode size in order
525 * to handle underlying block_device resize operations.
527 if (S_ISBLK(i
->i_mode
))
528 dev_size
= (i_size_read(i
) - fd_dev
->fd_block_size
);
530 dev_size
= fd_dev
->fd_dev_size
;
532 return div_u64(dev_size
, dev
->se_sub_dev
->se_dev_attrib
.block_size
);
535 static struct spc_ops fd_spc_ops
= {
536 .execute_rw
= fd_execute_rw
,
537 .execute_sync_cache
= fd_execute_sync_cache
,
540 static int fd_parse_cdb(struct se_cmd
*cmd
)
542 return sbc_parse_cdb(cmd
, &fd_spc_ops
);
545 static struct se_subsystem_api fileio_template
= {
547 .owner
= THIS_MODULE
,
548 .transport_type
= TRANSPORT_PLUGIN_VHBA_PDEV
,
549 .write_cache_emulated
= 1,
550 .fua_write_emulated
= 1,
551 .attach_hba
= fd_attach_hba
,
552 .detach_hba
= fd_detach_hba
,
553 .allocate_virtdevice
= fd_allocate_virtdevice
,
554 .create_virtdevice
= fd_create_virtdevice
,
555 .free_device
= fd_free_device
,
556 .parse_cdb
= fd_parse_cdb
,
557 .check_configfs_dev_params
= fd_check_configfs_dev_params
,
558 .set_configfs_dev_params
= fd_set_configfs_dev_params
,
559 .show_configfs_dev_params
= fd_show_configfs_dev_params
,
560 .get_device_rev
= fd_get_device_rev
,
561 .get_device_type
= fd_get_device_type
,
562 .get_blocks
= fd_get_blocks
,
565 static int __init
fileio_module_init(void)
567 return transport_subsystem_register(&fileio_template
);
570 static void fileio_module_exit(void)
572 transport_subsystem_release(&fileio_template
);
575 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
576 MODULE_AUTHOR("nab@Linux-iSCSI.org");
577 MODULE_LICENSE("GPL");
579 module_init(fileio_module_init
);
580 module_exit(fileio_module_exit
);