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 <scsi/scsi.h>
36 #include <scsi/scsi_host.h>
38 #include <target/target_core_base.h>
39 #include <target/target_core_device.h>
40 #include <target/target_core_transport.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 = (struct 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,
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;
120 struct inode *inode = NULL;
121 int dev_flags = 0, flags, ret = -EINVAL;
123 memset(&dev_limits, 0, sizeof(struct se_dev_limits));
127 dev_p = getname(fd_dev->fd_dev_name);
131 pr_err("getname(%s) failed: %lu\n",
132 fd_dev->fd_dev_name, IS_ERR(dev_p));
133 ret = PTR_ERR(dev_p);
137 if (di->no_create_file)
138 flags = O_RDWR | O_LARGEFILE;
140 flags = O_RDWR | O_CREAT | O_LARGEFILE;
142 flags = O_RDWR | O_CREAT | O_LARGEFILE;
144 /* flags |= O_DIRECT; */
146 * If fd_buffered_io=1 has not been set explicitly (the default),
147 * use O_SYNC to force FILEIO writes to disk.
149 if (!(fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO))
152 file = filp_open(dev_p, flags, 0600);
154 pr_err("filp_open(%s) failed\n", dev_p);
158 if (!file || !file->f_dentry) {
159 pr_err("filp_open(%s) failed\n", dev_p);
162 fd_dev->fd_file = file;
164 * If using a block backend with this struct file, we extract
165 * fd_dev->fd_[block,dev]_size from struct block_device.
167 * Otherwise, we use the passed fd_size= from configfs
169 inode = file->f_mapping->host;
170 if (S_ISBLK(inode->i_mode)) {
171 struct request_queue *q;
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.
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);
182 * Determine the number of bytes from i_size_read() minus
183 * one (1) logical sector from underlying struct block_device
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);
189 pr_debug("FILEIO: Using size: %llu bytes from struct"
190 " block_device blocks: %llu logical_block_size: %d\n",
192 div_u64(fd_dev->fd_dev_size, fd_dev->fd_block_size),
193 fd_dev->fd_block_size);
195 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
196 pr_err("FILEIO: Missing fd_dev_size="
197 " parameter, and no backing struct"
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;
209 dev_limits.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
210 dev_limits.queue_depth = FD_DEVICE_QUEUE_DEPTH;
212 dev = transport_add_device_to_core_hba(hba, &fileio_template,
213 se_dev, dev_flags, fd_dev,
214 &dev_limits, "FILEIO", FD_VERSION);
218 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
219 fd_dev->fd_queue_depth = dev->queue_depth;
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);
228 if (fd_dev->fd_file) {
229 filp_close(fd_dev->fd_file, NULL);
230 fd_dev->fd_file = NULL;
236 /* fd_free_device(): (Part of se_subsystem_api_t template)
240 static void fd_free_device(void *p)
242 struct fd_dev *fd_dev = (struct fd_dev *) p;
244 if (fd_dev->fd_file) {
245 filp_close(fd_dev->fd_file, NULL);
246 fd_dev->fd_file = NULL;
252 static inline struct fd_request *FILE_REQ(struct se_task *task)
254 return container_of(task, struct fd_request, fd_task);
258 static struct se_task *
259 fd_alloc_task(unsigned char *cdb)
261 struct fd_request *fd_req;
263 fd_req = kzalloc(sizeof(struct fd_request), GFP_KERNEL);
265 pr_err("Unable to allocate struct fd_request\n");
269 return &fd_req->fd_task;
272 static int fd_do_readv(struct se_task *task)
274 struct fd_request *req = FILE_REQ(task);
275 struct fd_dev *dev = req->fd_task.se_dev->dev_ptr;
276 struct file *fd = dev->fd_file;
277 struct scatterlist *sg = task->task_sg;
280 loff_t pos = (task->task_lba *
281 task->se_dev->se_sub_dev->se_dev_attrib.block_size);
284 iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL);
286 pr_err("Unable to allocate fd_do_readv iov[]\n");
290 for (i = 0; i < task->task_sg_nents; i++) {
291 iov[i].iov_len = sg[i].length;
292 iov[i].iov_base = sg_virt(&sg[i]);
297 ret = vfs_readv(fd, &iov[0], task->task_sg_nents, &pos);
302 * Return zeros and GOOD status even if the READ did not return
303 * the expected virt_size for struct file w/o a backing struct
306 if (S_ISBLK(fd->f_dentry->d_inode->i_mode)) {
307 if (ret < 0 || ret != task->task_size) {
308 pr_err("vfs_readv() returned %d,"
309 " expecting %d for S_ISBLK\n", ret,
310 (int)task->task_size);
311 return (ret < 0 ? ret : -EINVAL);
315 pr_err("vfs_readv() returned %d for non"
324 static int fd_do_writev(struct se_task *task)
326 struct fd_request *req = FILE_REQ(task);
327 struct fd_dev *dev = req->fd_task.se_dev->dev_ptr;
328 struct file *fd = dev->fd_file;
329 struct scatterlist *sg = task->task_sg;
332 loff_t pos = (task->task_lba *
333 task->se_dev->se_sub_dev->se_dev_attrib.block_size);
336 iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL);
338 pr_err("Unable to allocate fd_do_writev iov[]\n");
342 for (i = 0; i < task->task_sg_nents; i++) {
343 iov[i].iov_len = sg[i].length;
344 iov[i].iov_base = sg_virt(&sg[i]);
349 ret = vfs_writev(fd, &iov[0], task->task_sg_nents, &pos);
354 if (ret < 0 || ret != task->task_size) {
355 pr_err("vfs_writev() returned %d\n", ret);
356 return (ret < 0 ? ret : -EINVAL);
362 static void fd_emulate_sync_cache(struct se_task *task)
364 struct se_cmd *cmd = task->task_se_cmd;
365 struct se_device *dev = cmd->se_dev;
366 struct fd_dev *fd_dev = dev->dev_ptr;
367 int immed = (cmd->t_task_cdb[1] & 0x2);
372 * If the Immediate bit is set, queue up the GOOD response
373 * for this SYNCHRONIZE_CACHE op
376 transport_complete_sync_cache(cmd, 1);
379 * Determine if we will be flushing the entire device.
381 if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
385 start = cmd->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
386 if (cmd->data_length)
387 end = start + cmd->data_length;
392 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
394 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
397 transport_complete_sync_cache(cmd, ret == 0);
401 * Tell TCM Core that we are capable of WriteCache emulation for
402 * an underlying struct se_device.
404 static int fd_emulated_write_cache(struct se_device *dev)
409 static int fd_emulated_dpo(struct se_device *dev)
414 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs
417 static int fd_emulated_fua_write(struct se_device *dev)
422 static int fd_emulated_fua_read(struct se_device *dev)
428 * WRITE Force Unit Access (FUA) emulation on a per struct se_task
431 static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task)
433 struct se_device *dev = cmd->se_dev;
434 struct fd_dev *fd_dev = dev->dev_ptr;
435 loff_t start = task->task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
436 loff_t end = start + task->task_size;
439 pr_debug("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n",
440 task->task_lba, task->task_size);
442 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
444 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
447 static int fd_do_task(struct se_task *task)
449 struct se_cmd *cmd = task->task_se_cmd;
450 struct se_device *dev = cmd->se_dev;
454 * Call vectorized fileio functions to map struct scatterlist
455 * physical memory addresses to struct iovec virtual memory.
457 if (task->task_data_direction == DMA_FROM_DEVICE) {
458 ret = fd_do_readv(task);
460 ret = fd_do_writev(task);
463 dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0 &&
464 dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
467 * We might need to be a bit smarter here
468 * and return some sense data to let the initiator
469 * know the FUA WRITE cache sync failed..?
471 fd_emulate_write_fua(cmd, task);
479 task->task_scsi_status = GOOD;
480 transport_complete_task(task, 1);
482 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
485 /* fd_free_task(): (Part of se_subsystem_api_t template)
489 static void fd_free_task(struct se_task *task)
491 struct fd_request *req = FILE_REQ(task);
497 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
500 static match_table_t tokens = {
501 {Opt_fd_dev_name, "fd_dev_name=%s"},
502 {Opt_fd_dev_size, "fd_dev_size=%s"},
503 {Opt_fd_buffered_io, "fd_buffered_io=%d"},
507 static ssize_t fd_set_configfs_dev_params(
509 struct se_subsystem_dev *se_dev,
510 const char *page, ssize_t count)
512 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
513 char *orig, *ptr, *arg_p, *opts;
514 substring_t args[MAX_OPT_ARGS];
515 int ret = 0, arg, token;
517 opts = kstrdup(page, GFP_KERNEL);
523 while ((ptr = strsep(&opts, ",")) != NULL) {
527 token = match_token(ptr, tokens, args);
529 case Opt_fd_dev_name:
530 arg_p = match_strdup(&args[0]);
535 snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME,
538 pr_debug("FILEIO: Referencing Path: %s\n",
539 fd_dev->fd_dev_name);
540 fd_dev->fbd_flags |= FBDF_HAS_PATH;
542 case Opt_fd_dev_size:
543 arg_p = match_strdup(&args[0]);
548 ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size);
551 pr_err("strict_strtoull() failed for"
555 pr_debug("FILEIO: Referencing Size: %llu"
556 " bytes\n", fd_dev->fd_dev_size);
557 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
559 case Opt_fd_buffered_io:
560 match_int(args, &arg);
562 pr_err("bogus fd_buffered_io=%d value\n", arg);
567 pr_debug("FILEIO: Using buffered I/O"
568 " operations for struct fd_dev\n");
570 fd_dev->fbd_flags |= FDBD_USE_BUFFERED_IO;
579 return (!ret) ? count : ret;
582 static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev)
584 struct fd_dev *fd_dev = (struct fd_dev *) se_dev->se_dev_su_ptr;
586 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
587 pr_err("Missing fd_dev_name=\n");
594 static ssize_t fd_show_configfs_dev_params(
596 struct se_subsystem_dev *se_dev,
599 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
602 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
603 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s\n",
604 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
605 (fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO) ?
606 "Buffered" : "Synchronous");
610 /* fd_get_cdb(): (Part of se_subsystem_api_t template)
614 static unsigned char *fd_get_cdb(struct se_task *task)
616 struct fd_request *req = FILE_REQ(task);
618 return req->fd_scsi_cdb;
621 /* fd_get_device_rev(): (Part of se_subsystem_api_t template)
625 static u32 fd_get_device_rev(struct se_device *dev)
627 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
630 /* fd_get_device_type(): (Part of se_subsystem_api_t template)
634 static u32 fd_get_device_type(struct se_device *dev)
639 static sector_t fd_get_blocks(struct se_device *dev)
641 struct fd_dev *fd_dev = dev->dev_ptr;
642 unsigned long long blocks_long = div_u64(fd_dev->fd_dev_size,
643 dev->se_sub_dev->se_dev_attrib.block_size);
648 static struct se_subsystem_api fileio_template = {
650 .owner = THIS_MODULE,
651 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
652 .attach_hba = fd_attach_hba,
653 .detach_hba = fd_detach_hba,
654 .allocate_virtdevice = fd_allocate_virtdevice,
655 .create_virtdevice = fd_create_virtdevice,
656 .free_device = fd_free_device,
657 .dpo_emulated = fd_emulated_dpo,
658 .fua_write_emulated = fd_emulated_fua_write,
659 .fua_read_emulated = fd_emulated_fua_read,
660 .write_cache_emulated = fd_emulated_write_cache,
661 .alloc_task = fd_alloc_task,
662 .do_task = fd_do_task,
663 .do_sync_cache = fd_emulate_sync_cache,
664 .free_task = fd_free_task,
665 .check_configfs_dev_params = fd_check_configfs_dev_params,
666 .set_configfs_dev_params = fd_set_configfs_dev_params,
667 .show_configfs_dev_params = fd_show_configfs_dev_params,
668 .get_cdb = fd_get_cdb,
669 .get_device_rev = fd_get_device_rev,
670 .get_device_type = fd_get_device_type,
671 .get_blocks = fd_get_blocks,
674 static int __init fileio_module_init(void)
676 return transport_subsystem_register(&fileio_template);
679 static void fileio_module_exit(void)
681 transport_subsystem_release(&fileio_template);
684 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
685 MODULE_AUTHOR("nab@Linux-iSCSI.org");
686 MODULE_LICENSE("GPL");
688 module_init(fileio_module_init);
689 module_exit(fileio_module_exit);