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);