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/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>
39 #include <target/target_core_base.h>
40 #include <target/target_core_device.h>
41 #include <target/target_core_transport.h>
43 #include "target_core_file.h"
46 #define DEBUG_FD_CACHE(x...) printk(x)
48 #define DEBUG_FD_CACHE(x...)
52 #define DEBUG_FD_FUA(x...) printk(x)
54 #define DEBUG_FD_FUA(x...)
57 static struct se_subsystem_api fileio_template;
59 /* fd_attach_hba(): (Part of se_subsystem_api_t template)
63 static int fd_attach_hba(struct se_hba *hba, u32 host_id)
65 struct fd_host *fd_host;
67 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
69 printk(KERN_ERR "Unable to allocate memory for struct fd_host\n");
73 fd_host->fd_host_id = host_id;
75 hba->hba_ptr = fd_host;
77 printk(KERN_INFO "CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
78 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
79 TARGET_CORE_MOD_VERSION);
80 printk(KERN_INFO "CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic"
82 hba->hba_id, fd_host->fd_host_id, FD_MAX_SECTORS);
87 static void fd_detach_hba(struct se_hba *hba)
89 struct fd_host *fd_host = hba->hba_ptr;
91 printk(KERN_INFO "CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
92 " Target Core\n", hba->hba_id, fd_host->fd_host_id);
98 static void *fd_allocate_virtdevice(struct se_hba *hba, const char *name)
100 struct fd_dev *fd_dev;
101 struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr;
103 fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
105 printk(KERN_ERR "Unable to allocate memory for struct fd_dev\n");
109 fd_dev->fd_host = fd_host;
111 printk(KERN_INFO "FILEIO: Allocated fd_dev for %p\n", name);
116 /* fd_create_virtdevice(): (Part of se_subsystem_api_t template)
120 static struct se_device *fd_create_virtdevice(
122 struct se_subsystem_dev *se_dev,
126 struct se_device *dev;
127 struct se_dev_limits dev_limits;
128 struct queue_limits *limits;
129 struct fd_dev *fd_dev = (struct fd_dev *) p;
130 struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr;
133 struct inode *inode = NULL;
134 int dev_flags = 0, flags, ret = -EINVAL;
136 memset(&dev_limits, 0, sizeof(struct se_dev_limits));
140 dev_p = getname(fd_dev->fd_dev_name);
144 printk(KERN_ERR "getname(%s) failed: %lu\n",
145 fd_dev->fd_dev_name, IS_ERR(dev_p));
146 ret = PTR_ERR(dev_p);
150 if (di->no_create_file)
151 flags = O_RDWR | O_LARGEFILE;
153 flags = O_RDWR | O_CREAT | O_LARGEFILE;
155 flags = O_RDWR | O_CREAT | O_LARGEFILE;
157 /* flags |= O_DIRECT; */
159 * If fd_buffered_io=1 has not been set explicitly (the default),
160 * use O_SYNC to force FILEIO writes to disk.
162 if (!(fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO))
165 file = filp_open(dev_p, flags, 0600);
167 printk(KERN_ERR "filp_open(%s) failed\n", dev_p);
171 if (!file || !file->f_dentry) {
172 printk(KERN_ERR "filp_open(%s) failed\n", dev_p);
175 fd_dev->fd_file = file;
177 * If using a block backend with this struct file, we extract
178 * fd_dev->fd_[block,dev]_size from struct block_device.
180 * Otherwise, we use the passed fd_size= from configfs
182 inode = file->f_mapping->host;
183 if (S_ISBLK(inode->i_mode)) {
184 struct request_queue *q;
186 * Setup the local scope queue_limits from struct request_queue->limits
187 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
189 q = bdev_get_queue(inode->i_bdev);
190 limits = &dev_limits.limits;
191 limits->logical_block_size = bdev_logical_block_size(inode->i_bdev);
192 limits->max_hw_sectors = queue_max_hw_sectors(q);
193 limits->max_sectors = queue_max_sectors(q);
195 * Determine the number of bytes from i_size_read() minus
196 * one (1) logical sector from underlying struct block_device
198 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
199 fd_dev->fd_dev_size = (i_size_read(file->f_mapping->host) -
200 fd_dev->fd_block_size);
202 printk(KERN_INFO "FILEIO: Using size: %llu bytes from struct"
203 " block_device blocks: %llu logical_block_size: %d\n",
205 div_u64(fd_dev->fd_dev_size, fd_dev->fd_block_size),
206 fd_dev->fd_block_size);
208 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
209 printk(KERN_ERR "FILEIO: Missing fd_dev_size="
210 " parameter, and no backing struct"
215 limits = &dev_limits.limits;
216 limits->logical_block_size = FD_BLOCKSIZE;
217 limits->max_hw_sectors = FD_MAX_SECTORS;
218 limits->max_sectors = FD_MAX_SECTORS;
219 fd_dev->fd_block_size = FD_BLOCKSIZE;
222 dev_limits.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
223 dev_limits.queue_depth = FD_DEVICE_QUEUE_DEPTH;
225 dev = transport_add_device_to_core_hba(hba, &fileio_template,
226 se_dev, dev_flags, (void *)fd_dev,
227 &dev_limits, "FILEIO", FD_VERSION);
231 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
232 fd_dev->fd_queue_depth = dev->queue_depth;
234 printk(KERN_INFO "CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
235 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
236 fd_dev->fd_dev_name, fd_dev->fd_dev_size);
241 if (fd_dev->fd_file) {
242 filp_close(fd_dev->fd_file, NULL);
243 fd_dev->fd_file = NULL;
249 /* fd_free_device(): (Part of se_subsystem_api_t template)
253 static void fd_free_device(void *p)
255 struct fd_dev *fd_dev = (struct fd_dev *) p;
257 if (fd_dev->fd_file) {
258 filp_close(fd_dev->fd_file, NULL);
259 fd_dev->fd_file = NULL;
265 static inline struct fd_request *FILE_REQ(struct se_task *task)
267 return container_of(task, struct fd_request, fd_task);
271 static struct se_task *
272 fd_alloc_task(struct se_cmd *cmd)
274 struct fd_request *fd_req;
276 fd_req = kzalloc(sizeof(struct fd_request), GFP_KERNEL);
278 printk(KERN_ERR "Unable to allocate struct fd_request\n");
282 fd_req->fd_dev = cmd->se_lun->lun_se_dev->dev_ptr;
284 return &fd_req->fd_task;
287 static int fd_do_readv(struct se_task *task)
289 struct fd_request *req = FILE_REQ(task);
290 struct file *fd = req->fd_dev->fd_file;
291 struct scatterlist *sg = task->task_sg;
294 loff_t pos = (task->task_lba *
295 task->se_dev->se_sub_dev->se_dev_attrib.block_size);
298 iov = kzalloc(sizeof(struct iovec) * task->task_sg_num, GFP_KERNEL);
300 printk(KERN_ERR "Unable to allocate fd_do_readv iov[]\n");
304 for (i = 0; i < task->task_sg_num; i++) {
305 iov[i].iov_len = sg[i].length;
306 iov[i].iov_base = sg_virt(&sg[i]);
311 ret = vfs_readv(fd, &iov[0], task->task_sg_num, &pos);
316 * Return zeros and GOOD status even if the READ did not return
317 * the expected virt_size for struct file w/o a backing struct
320 if (S_ISBLK(fd->f_dentry->d_inode->i_mode)) {
321 if (ret < 0 || ret != task->task_size) {
322 printk(KERN_ERR "vfs_readv() returned %d,"
323 " expecting %d for S_ISBLK\n", ret,
324 (int)task->task_size);
325 return (ret < 0 ? ret : -EINVAL);
329 printk(KERN_ERR "vfs_readv() returned %d for non"
338 static int fd_do_writev(struct se_task *task)
340 struct fd_request *req = FILE_REQ(task);
341 struct file *fd = req->fd_dev->fd_file;
342 struct scatterlist *sg = task->task_sg;
345 loff_t pos = (task->task_lba *
346 task->se_dev->se_sub_dev->se_dev_attrib.block_size);
349 iov = kzalloc(sizeof(struct iovec) * task->task_sg_num, GFP_KERNEL);
351 printk(KERN_ERR "Unable to allocate fd_do_writev iov[]\n");
355 for (i = 0; i < task->task_sg_num; i++) {
356 iov[i].iov_len = sg[i].length;
357 iov[i].iov_base = sg_virt(&sg[i]);
362 ret = vfs_writev(fd, &iov[0], task->task_sg_num, &pos);
367 if (ret < 0 || ret != task->task_size) {
368 printk(KERN_ERR "vfs_writev() returned %d\n", ret);
369 return (ret < 0 ? ret : -EINVAL);
375 static void fd_emulate_sync_cache(struct se_task *task)
377 struct se_cmd *cmd = task->task_se_cmd;
378 struct se_device *dev = cmd->se_dev;
379 struct fd_dev *fd_dev = dev->dev_ptr;
380 int immed = (cmd->t_task->t_task_cdb[1] & 0x2);
385 * If the Immediate bit is set, queue up the GOOD response
386 * for this SYNCHRONIZE_CACHE op
389 transport_complete_sync_cache(cmd, 1);
392 * Determine if we will be flushing the entire device.
394 if (cmd->t_task->t_task_lba == 0 && cmd->data_length == 0) {
398 start = cmd->t_task->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
399 if (cmd->data_length)
400 end = start + cmd->data_length;
405 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
407 printk(KERN_ERR "FILEIO: vfs_fsync_range() failed: %d\n", ret);
410 transport_complete_sync_cache(cmd, ret == 0);
414 * Tell TCM Core that we are capable of WriteCache emulation for
415 * an underlying struct se_device.
417 static int fd_emulated_write_cache(struct se_device *dev)
422 static int fd_emulated_dpo(struct se_device *dev)
427 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs
430 static int fd_emulated_fua_write(struct se_device *dev)
435 static int fd_emulated_fua_read(struct se_device *dev)
441 * WRITE Force Unit Access (FUA) emulation on a per struct se_task
444 static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task)
446 struct se_device *dev = cmd->se_dev;
447 struct fd_dev *fd_dev = dev->dev_ptr;
448 loff_t start = task->task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
449 loff_t end = start + task->task_size;
452 DEBUG_FD_CACHE("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n",
453 task->task_lba, task->task_size);
455 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
457 printk(KERN_ERR "FILEIO: vfs_fsync_range() failed: %d\n", ret);
460 static int fd_do_task(struct se_task *task)
462 struct se_cmd *cmd = task->task_se_cmd;
463 struct se_device *dev = cmd->se_dev;
467 * Call vectorized fileio functions to map struct scatterlist
468 * physical memory addresses to struct iovec virtual memory.
470 if (task->task_data_direction == DMA_FROM_DEVICE) {
471 ret = fd_do_readv(task);
473 ret = fd_do_writev(task);
476 dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0 &&
477 dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
478 cmd->t_task->t_tasks_fua) {
480 * We might need to be a bit smarter here
481 * and return some sense data to let the initiator
482 * know the FUA WRITE cache sync failed..?
484 fd_emulate_write_fua(cmd, task);
492 task->task_scsi_status = GOOD;
493 transport_complete_task(task, 1);
495 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
498 /* fd_free_task(): (Part of se_subsystem_api_t template)
502 static void fd_free_task(struct se_task *task)
504 struct fd_request *req = FILE_REQ(task);
510 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
513 static match_table_t tokens = {
514 {Opt_fd_dev_name, "fd_dev_name=%s"},
515 {Opt_fd_dev_size, "fd_dev_size=%s"},
516 {Opt_fd_buffered_io, "fd_buffered_io=%d"},
520 static ssize_t fd_set_configfs_dev_params(
522 struct se_subsystem_dev *se_dev,
523 const char *page, ssize_t count)
525 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
526 char *orig, *ptr, *arg_p, *opts;
527 substring_t args[MAX_OPT_ARGS];
528 int ret = 0, arg, token;
530 opts = kstrdup(page, GFP_KERNEL);
536 while ((ptr = strsep(&opts, ",")) != NULL) {
540 token = match_token(ptr, tokens, args);
542 case Opt_fd_dev_name:
543 arg_p = match_strdup(&args[0]);
548 snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME,
551 printk(KERN_INFO "FILEIO: Referencing Path: %s\n",
552 fd_dev->fd_dev_name);
553 fd_dev->fbd_flags |= FBDF_HAS_PATH;
555 case Opt_fd_dev_size:
556 arg_p = match_strdup(&args[0]);
561 ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size);
564 printk(KERN_ERR "strict_strtoull() failed for"
568 printk(KERN_INFO "FILEIO: Referencing Size: %llu"
569 " bytes\n", fd_dev->fd_dev_size);
570 fd_dev->fbd_flags |= FBDF_HAS_SIZE;
572 case Opt_fd_buffered_io:
573 match_int(args, &arg);
575 printk(KERN_ERR "bogus fd_buffered_io=%d value\n", arg);
580 printk(KERN_INFO "FILEIO: Using buffered I/O"
581 " operations for struct fd_dev\n");
583 fd_dev->fbd_flags |= FDBD_USE_BUFFERED_IO;
592 return (!ret) ? count : ret;
595 static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev)
597 struct fd_dev *fd_dev = (struct fd_dev *) se_dev->se_dev_su_ptr;
599 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
600 printk(KERN_ERR "Missing fd_dev_name=\n");
607 static ssize_t fd_show_configfs_dev_params(
609 struct se_subsystem_dev *se_dev,
612 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr;
615 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
616 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s\n",
617 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
618 (fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO) ?
619 "Buffered" : "Synchronous");
623 /* fd_get_cdb(): (Part of se_subsystem_api_t template)
627 static unsigned char *fd_get_cdb(struct se_task *task)
629 struct fd_request *req = FILE_REQ(task);
631 return req->fd_scsi_cdb;
634 /* fd_get_device_rev(): (Part of se_subsystem_api_t template)
638 static u32 fd_get_device_rev(struct se_device *dev)
640 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
643 /* fd_get_device_type(): (Part of se_subsystem_api_t template)
647 static u32 fd_get_device_type(struct se_device *dev)
652 static sector_t fd_get_blocks(struct se_device *dev)
654 struct fd_dev *fd_dev = dev->dev_ptr;
655 unsigned long long blocks_long = div_u64(fd_dev->fd_dev_size,
656 dev->se_sub_dev->se_dev_attrib.block_size);
661 static struct se_subsystem_api fileio_template = {
663 .owner = THIS_MODULE,
664 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
665 .attach_hba = fd_attach_hba,
666 .detach_hba = fd_detach_hba,
667 .allocate_virtdevice = fd_allocate_virtdevice,
668 .create_virtdevice = fd_create_virtdevice,
669 .free_device = fd_free_device,
670 .dpo_emulated = fd_emulated_dpo,
671 .fua_write_emulated = fd_emulated_fua_write,
672 .fua_read_emulated = fd_emulated_fua_read,
673 .write_cache_emulated = fd_emulated_write_cache,
674 .alloc_task = fd_alloc_task,
675 .do_task = fd_do_task,
676 .do_sync_cache = fd_emulate_sync_cache,
677 .free_task = fd_free_task,
678 .check_configfs_dev_params = fd_check_configfs_dev_params,
679 .set_configfs_dev_params = fd_set_configfs_dev_params,
680 .show_configfs_dev_params = fd_show_configfs_dev_params,
681 .get_cdb = fd_get_cdb,
682 .get_device_rev = fd_get_device_rev,
683 .get_device_type = fd_get_device_type,
684 .get_blocks = fd_get_blocks,
687 static int __init fileio_module_init(void)
689 return transport_subsystem_register(&fileio_template);
692 static void fileio_module_exit(void)
694 transport_subsystem_release(&fileio_template);
697 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
698 MODULE_AUTHOR("nab@Linux-iSCSI.org");
699 MODULE_LICENSE("GPL");
701 module_init(fileio_module_init);
702 module_exit(fileio_module_exit);