linux/drivers/target/target_core_file.c
Linus Torvalds 5c755fe142 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
 "It's been a busy development cycle for target-core in a number of
  different areas.

  The fabric API usage for se_node_acl allocation is now within
  target-core code, dropping the external API callers for all fabric
  drivers tree-wide.

  There is a new conversion to RCU hlists for se_node_acl and
  se_portal_group LUN mappings, that turns fast-past LUN lookup into a
  completely lockless code-path.  It also removes the original
  hard-coded limitation of 256 LUNs per fabric endpoint.

  The configfs attributes for backends can now be shared between core
  and driver code, allowing existing drivers to use common code while
  still allowing flexibility for new backend provided attributes.

  The highlights include:

   - Merge sbc_verify_dif_* into common code (sagi)
   - Remove iscsi-target support for obsolete IFMarker/OFMarker
     (Christophe Vu-Brugier)
   - Add bidi support in target/user backend (ilias + vangelis + agover)
   - Move se_node_acl allocation into target-core code (hch)
   - Add crc_t10dif_update common helper (akinobu + mkp)
   - Handle target-core odd SGL mapping for data transfer memory
     (akinobu)
   - Move transport ID handling into target-core (hch)
   - Move task tag into struct se_cmd + support 64-bit tags (bart)
   - Convert se_node_acl->device_list[] to RCU hlist (nab + hch +
     paulmck)
   - Convert se_portal_group->tpg_lun_list[] to RCU hlist (nab + hch +
     paulmck)
   - Simplify target backend driver registration (hch)
   - Consolidate + simplify target backend attribute implementations
     (hch + nab)
   - Subsume se_port + t10_alua_tg_pt_gp_member into se_lun (hch)
   - Drop lun_sep_lock for se_lun->lun_se_dev RCU usage (hch + nab)
   - Drop unnecessary core_tpg_register TFO parameter (nab)
   - Use 64-bit LUNs tree-wide (hannes)
   - Drop left-over TARGET_MAX_LUNS_PER_TRANSPORT limit (hannes)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (76 commits)
  target: Bump core version to v5.0
  target: remove target_core_configfs.h
  target: remove unused TARGET_CORE_CONFIG_ROOT define
  target: consolidate version defines
  target: implement WRITE_SAME with UNMAP bit using ->execute_unmap
  target: simplify UNMAP handling
  target: replace se_cmd->execute_rw with a protocol_data field
  target/user: Fix inconsistent kmap_atomic/kunmap_atomic
  target: Send UA when changing LUN inventory
  target: Send UA upon LUN RESET tmr completion
  target: Send UA on ALUA target port group change
  target: Convert se_lun->lun_deve_lock to normal spinlock
  target: use 'se_dev_entry' when allocating UAs
  target: Remove 'ua_nacl' pointer from se_ua structure
  target_core_alua: Correct UA handling when switching states
  xen-scsiback: Fix compile warning for 64-bit LUN
  target: Remove TARGET_MAX_LUNS_PER_TRANSPORT
  target: use 64-bit LUNs
  target: Drop duplicate + unused se_dev_check_wce
  target: Drop unnecessary core_tpg_register TFO parameter
  ...
2015-07-04 14:13:43 -07:00

856 lines
22 KiB
C

/*******************************************************************************
* Filename: target_core_file.c
*
* This file contains the Storage Engine <-> FILEIO transport specific functions
*
* (c) Copyright 2005-2013 Datera, Inc.
*
* Nicholas A. Bellinger <nab@kernel.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
******************************************************************************/
#include <linux/string.h>
#include <linux/parser.h>
#include <linux/timer.h>
#include <linux/blkdev.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/falloc.h>
#include <scsi/scsi_proto.h>
#include <asm/unaligned.h>
#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include "target_core_file.h"
static inline struct fd_dev *FD_DEV(struct se_device *dev)
{
return container_of(dev, struct fd_dev, dev);
}
static int fd_attach_hba(struct se_hba *hba, u32 host_id)
{
struct fd_host *fd_host;
fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
if (!fd_host) {
pr_err("Unable to allocate memory for struct fd_host\n");
return -ENOMEM;
}
fd_host->fd_host_id = host_id;
hba->hba_ptr = fd_host;
pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
" Target Core Stack %s\n", hba->hba_id, FD_VERSION,
TARGET_CORE_VERSION);
pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n",
hba->hba_id, fd_host->fd_host_id);
return 0;
}
static void fd_detach_hba(struct se_hba *hba)
{
struct fd_host *fd_host = hba->hba_ptr;
pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
" Target Core\n", hba->hba_id, fd_host->fd_host_id);
kfree(fd_host);
hba->hba_ptr = NULL;
}
static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name)
{
struct fd_dev *fd_dev;
struct fd_host *fd_host = hba->hba_ptr;
fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
if (!fd_dev) {
pr_err("Unable to allocate memory for struct fd_dev\n");
return NULL;
}
fd_dev->fd_host = fd_host;
pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
return &fd_dev->dev;
}
static int fd_configure_device(struct se_device *dev)
{
struct fd_dev *fd_dev = FD_DEV(dev);
struct fd_host *fd_host = dev->se_hba->hba_ptr;
struct file *file;
struct inode *inode = NULL;
int flags, ret = -EINVAL;
if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
pr_err("Missing fd_dev_name=\n");
return -EINVAL;
}
/*
* Use O_DSYNC by default instead of O_SYNC to forgo syncing
* of pure timestamp updates.
*/
flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
/*
* Optionally allow fd_buffered_io=1 to be enabled for people
* who want use the fs buffer cache as an WriteCache mechanism.
*
* This means that in event of a hard failure, there is a risk
* of silent data-loss if the SCSI client has *not* performed a
* forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
* to write-out the entire device cache.
*/
if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
flags &= ~O_DSYNC;
}
file = filp_open(fd_dev->fd_dev_name, flags, 0600);
if (IS_ERR(file)) {
pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
ret = PTR_ERR(file);
goto fail;
}
fd_dev->fd_file = file;
/*
* If using a block backend with this struct file, we extract
* fd_dev->fd_[block,dev]_size from struct block_device.
*
* Otherwise, we use the passed fd_size= from configfs
*/
inode = file->f_mapping->host;
if (S_ISBLK(inode->i_mode)) {
struct request_queue *q = bdev_get_queue(inode->i_bdev);
unsigned long long dev_size;
fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
/*
* Determine the number of bytes from i_size_read() minus
* one (1) logical sector from underlying struct block_device
*/
dev_size = (i_size_read(file->f_mapping->host) -
fd_dev->fd_block_size);
pr_debug("FILEIO: Using size: %llu bytes from struct"
" block_device blocks: %llu logical_block_size: %d\n",
dev_size, div_u64(dev_size, fd_dev->fd_block_size),
fd_dev->fd_block_size);
/*
* Check if the underlying struct block_device request_queue supports
* the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
* in ATA and we need to set TPE=1
*/
if (blk_queue_discard(q)) {
dev->dev_attrib.max_unmap_lba_count =
q->limits.max_discard_sectors;
/*
* Currently hardcoded to 1 in Linux/SCSI code..
*/
dev->dev_attrib.max_unmap_block_desc_count = 1;
dev->dev_attrib.unmap_granularity =
q->limits.discard_granularity >> 9;
dev->dev_attrib.unmap_granularity_alignment =
q->limits.discard_alignment;
pr_debug("IFILE: BLOCK Discard support available,"
" disabled by default\n");
}
/*
* Enable write same emulation for IBLOCK and use 0xFFFF as
* the smaller WRITE_SAME(10) only has a two-byte block count.
*/
dev->dev_attrib.max_write_same_len = 0xFFFF;
if (blk_queue_nonrot(q))
dev->dev_attrib.is_nonrot = 1;
} else {
if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
pr_err("FILEIO: Missing fd_dev_size="
" parameter, and no backing struct"
" block_device\n");
goto fail;
}
fd_dev->fd_block_size = FD_BLOCKSIZE;
/*
* Limit UNMAP emulation to 8k Number of LBAs (NoLB)
*/
dev->dev_attrib.max_unmap_lba_count = 0x2000;
/*
* Currently hardcoded to 1 in Linux/SCSI code..
*/
dev->dev_attrib.max_unmap_block_desc_count = 1;
dev->dev_attrib.unmap_granularity = 1;
dev->dev_attrib.unmap_granularity_alignment = 0;
/*
* Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
* based upon struct iovec limit for vfs_writev()
*/
dev->dev_attrib.max_write_same_len = 0x1000;
}
dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES;
dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
" with FDBD_HAS_BUFFERED_IO_WCE\n");
dev->dev_attrib.emulate_write_cache = 1;
}
fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
fd_dev->fd_queue_depth = dev->queue_depth;
pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
" %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
fd_dev->fd_dev_name, fd_dev->fd_dev_size);
return 0;
fail:
if (fd_dev->fd_file) {
filp_close(fd_dev->fd_file, NULL);
fd_dev->fd_file = NULL;
}
return ret;
}
static void fd_dev_call_rcu(struct rcu_head *p)
{
struct se_device *dev = container_of(p, struct se_device, rcu_head);
struct fd_dev *fd_dev = FD_DEV(dev);
kfree(fd_dev);
}
static void fd_free_device(struct se_device *dev)
{
struct fd_dev *fd_dev = FD_DEV(dev);
if (fd_dev->fd_file) {
filp_close(fd_dev->fd_file, NULL);
fd_dev->fd_file = NULL;
}
call_rcu(&dev->rcu_head, fd_dev_call_rcu);
}
static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
u32 block_size, struct scatterlist *sgl,
u32 sgl_nents, u32 data_length, int is_write)
{
struct scatterlist *sg;
struct iov_iter iter;
struct bio_vec *bvec;
ssize_t len = 0;
loff_t pos = (cmd->t_task_lba * block_size);
int ret = 0, i;
bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
if (!bvec) {
pr_err("Unable to allocate fd_do_readv iov[]\n");
return -ENOMEM;
}
for_each_sg(sgl, sg, sgl_nents, i) {
bvec[i].bv_page = sg_page(sg);
bvec[i].bv_len = sg->length;
bvec[i].bv_offset = sg->offset;
len += sg->length;
}
iov_iter_bvec(&iter, ITER_BVEC, bvec, sgl_nents, len);
if (is_write)
ret = vfs_iter_write(fd, &iter, &pos);
else
ret = vfs_iter_read(fd, &iter, &pos);
kfree(bvec);
if (is_write) {
if (ret < 0 || ret != data_length) {
pr_err("%s() write returned %d\n", __func__, ret);
return (ret < 0 ? ret : -EINVAL);
}
} else {
/*
* Return zeros and GOOD status even if the READ did not return
* the expected virt_size for struct file w/o a backing struct
* block_device.
*/
if (S_ISBLK(file_inode(fd)->i_mode)) {
if (ret < 0 || ret != data_length) {
pr_err("%s() returned %d, expecting %u for "
"S_ISBLK\n", __func__, ret,
data_length);
return (ret < 0 ? ret : -EINVAL);
}
} else {
if (ret < 0) {
pr_err("%s() returned %d for non S_ISBLK\n",
__func__, ret);
return ret;
}
}
}
return 1;
}
static sense_reason_t
fd_execute_sync_cache(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
struct fd_dev *fd_dev = FD_DEV(dev);
int immed = (cmd->t_task_cdb[1] & 0x2);
loff_t start, end;
int ret;
/*
* If the Immediate bit is set, queue up the GOOD response
* for this SYNCHRONIZE_CACHE op
*/
if (immed)
target_complete_cmd(cmd, SAM_STAT_GOOD);
/*
* Determine if we will be flushing the entire device.
*/
if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
start = 0;
end = LLONG_MAX;
} else {
start = cmd->t_task_lba * dev->dev_attrib.block_size;
if (cmd->data_length)
end = start + cmd->data_length - 1;
else
end = LLONG_MAX;
}
ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
if (ret != 0)
pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
if (immed)
return 0;
if (ret)
target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
else
target_complete_cmd(cmd, SAM_STAT_GOOD);
return 0;
}
static sense_reason_t
fd_execute_write_same(struct se_cmd *cmd)
{
struct se_device *se_dev = cmd->se_dev;
struct fd_dev *fd_dev = FD_DEV(se_dev);
loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
sector_t nolb = sbc_get_write_same_sectors(cmd);
struct iov_iter iter;
struct bio_vec *bvec;
unsigned int len = 0, i;
ssize_t ret;
if (!nolb) {
target_complete_cmd(cmd, SAM_STAT_GOOD);
return 0;
}
if (cmd->prot_op) {
pr_err("WRITE_SAME: Protection information with FILEIO"
" backends not supported\n");
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
if (cmd->t_data_nents > 1 ||
cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
" block_size: %u\n",
cmd->t_data_nents,
cmd->t_data_sg[0].length,
cmd->se_dev->dev_attrib.block_size);
return TCM_INVALID_CDB_FIELD;
}
bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
if (!bvec)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
for (i = 0; i < nolb; i++) {
bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
bvec[i].bv_len = cmd->t_data_sg[0].length;
bvec[i].bv_offset = cmd->t_data_sg[0].offset;
len += se_dev->dev_attrib.block_size;
}
iov_iter_bvec(&iter, ITER_BVEC, bvec, nolb, len);
ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos);
kfree(bvec);
if (ret < 0 || ret != len) {
pr_err("vfs_iter_write() returned %zd for write same\n", ret);
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
target_complete_cmd(cmd, SAM_STAT_GOOD);
return 0;
}
static int
fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
void *buf, size_t bufsize)
{
struct fd_dev *fd_dev = FD_DEV(se_dev);
struct file *prot_fd = fd_dev->fd_prot_file;
sector_t prot_length, prot;
loff_t pos = lba * se_dev->prot_length;
if (!prot_fd) {
pr_err("Unable to locate fd_dev->fd_prot_file\n");
return -ENODEV;
}
prot_length = nolb * se_dev->prot_length;
for (prot = 0; prot < prot_length;) {
sector_t len = min_t(sector_t, bufsize, prot_length - prot);
ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
if (ret != len) {
pr_err("vfs_write to prot file failed: %zd\n", ret);
return ret < 0 ? ret : -ENODEV;
}
prot += ret;
}
return 0;
}
static int
fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
{
void *buf;
int rc;
buf = (void *)__get_free_page(GFP_KERNEL);
if (!buf) {
pr_err("Unable to allocate FILEIO prot buf\n");
return -ENOMEM;
}
memset(buf, 0xff, PAGE_SIZE);
rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
free_page((unsigned long)buf);
return rc;
}
static sense_reason_t
fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
{
struct file *file = FD_DEV(cmd->se_dev)->fd_file;
struct inode *inode = file->f_mapping->host;
int ret;
if (cmd->se_dev->dev_attrib.pi_prot_type) {
ret = fd_do_prot_unmap(cmd, lba, nolb);
if (ret)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
if (S_ISBLK(inode->i_mode)) {
/* The backend is block device, use discard */
struct block_device *bdev = inode->i_bdev;
ret = blkdev_issue_discard(bdev, lba,
nolb, GFP_KERNEL, 0);
if (ret < 0) {
pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
ret);
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
} else {
/* The backend is normal file, use fallocate */
struct se_device *se_dev = cmd->se_dev;
loff_t pos = lba * se_dev->dev_attrib.block_size;
unsigned int len = nolb * se_dev->dev_attrib.block_size;
int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
if (!file->f_op->fallocate)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
ret = file->f_op->fallocate(file, mode, pos, len);
if (ret < 0) {
pr_warn("FILEIO: fallocate() failed: %d\n", ret);
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
}
return 0;
}
static sense_reason_t
fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
enum dma_data_direction data_direction)
{
struct se_device *dev = cmd->se_dev;
struct fd_dev *fd_dev = FD_DEV(dev);
struct file *file = fd_dev->fd_file;
struct file *pfile = fd_dev->fd_prot_file;
sense_reason_t rc;
int ret = 0;
/*
* We are currently limited by the number of iovecs (2048) per
* single vfs_[writev,readv] call.
*/
if (cmd->data_length > FD_MAX_BYTES) {
pr_err("FILEIO: Not able to process I/O of %u bytes due to"
"FD_MAX_BYTES: %u iovec count limitiation\n",
cmd->data_length, FD_MAX_BYTES);
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
/*
* Call vectorized fileio functions to map struct scatterlist
* physical memory addresses to struct iovec virtual memory.
*/
if (data_direction == DMA_FROM_DEVICE) {
if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
ret = fd_do_rw(cmd, pfile, dev->prot_length,
cmd->t_prot_sg, cmd->t_prot_nents,
cmd->prot_length, 0);
if (ret < 0)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
sgl, sgl_nents, cmd->data_length, 0);
if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
u32 sectors = cmd->data_length >>
ilog2(dev->dev_attrib.block_size);
rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
0, cmd->t_prot_sg, 0);
if (rc)
return rc;
}
} else {
if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
u32 sectors = cmd->data_length >>
ilog2(dev->dev_attrib.block_size);
rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
0, cmd->t_prot_sg, 0);
if (rc)
return rc;
}
ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
sgl, sgl_nents, cmd->data_length, 1);
/*
* Perform implicit vfs_fsync_range() for fd_do_writev() ops
* for SCSI WRITEs with Forced Unit Access (FUA) set.
* Allow this to happen independent of WCE=0 setting.
*/
if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
loff_t start = cmd->t_task_lba *
dev->dev_attrib.block_size;
loff_t end;
if (cmd->data_length)
end = start + cmd->data_length - 1;
else
end = LLONG_MAX;
vfs_fsync_range(fd_dev->fd_file, start, end, 1);
}
if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
ret = fd_do_rw(cmd, pfile, dev->prot_length,
cmd->t_prot_sg, cmd->t_prot_nents,
cmd->prot_length, 1);
if (ret < 0)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
}
if (ret < 0)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
if (ret)
target_complete_cmd(cmd, SAM_STAT_GOOD);
return 0;
}
enum {
Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
};
static match_table_t tokens = {
{Opt_fd_dev_name, "fd_dev_name=%s"},
{Opt_fd_dev_size, "fd_dev_size=%s"},
{Opt_fd_buffered_io, "fd_buffered_io=%d"},
{Opt_err, NULL}
};
static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
const char *page, ssize_t count)
{
struct fd_dev *fd_dev = FD_DEV(dev);
char *orig, *ptr, *arg_p, *opts;
substring_t args[MAX_OPT_ARGS];
int ret = 0, arg, token;
opts = kstrdup(page, GFP_KERNEL);
if (!opts)
return -ENOMEM;
orig = opts;
while ((ptr = strsep(&opts, ",\n")) != NULL) {
if (!*ptr)
continue;
token = match_token(ptr, tokens, args);
switch (token) {
case Opt_fd_dev_name:
if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
FD_MAX_DEV_NAME) == 0) {
ret = -EINVAL;
break;
}
pr_debug("FILEIO: Referencing Path: %s\n",
fd_dev->fd_dev_name);
fd_dev->fbd_flags |= FBDF_HAS_PATH;
break;
case Opt_fd_dev_size:
arg_p = match_strdup(&args[0]);
if (!arg_p) {
ret = -ENOMEM;
break;
}
ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
kfree(arg_p);
if (ret < 0) {
pr_err("kstrtoull() failed for"
" fd_dev_size=\n");
goto out;
}
pr_debug("FILEIO: Referencing Size: %llu"
" bytes\n", fd_dev->fd_dev_size);
fd_dev->fbd_flags |= FBDF_HAS_SIZE;
break;
case Opt_fd_buffered_io:
ret = match_int(args, &arg);
if (ret)
goto out;
if (arg != 1) {
pr_err("bogus fd_buffered_io=%d value\n", arg);
ret = -EINVAL;
goto out;
}
pr_debug("FILEIO: Using buffered I/O"
" operations for struct fd_dev\n");
fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
break;
default:
break;
}
}
out:
kfree(orig);
return (!ret) ? count : ret;
}
static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
{
struct fd_dev *fd_dev = FD_DEV(dev);
ssize_t bl = 0;
bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s\n",
fd_dev->fd_dev_name, fd_dev->fd_dev_size,
(fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
"Buffered-WCE" : "O_DSYNC");
return bl;
}
static sector_t fd_get_blocks(struct se_device *dev)
{
struct fd_dev *fd_dev = FD_DEV(dev);
struct file *f = fd_dev->fd_file;
struct inode *i = f->f_mapping->host;
unsigned long long dev_size;
/*
* When using a file that references an underlying struct block_device,
* ensure dev_size is always based on the current inode size in order
* to handle underlying block_device resize operations.
*/
if (S_ISBLK(i->i_mode))
dev_size = i_size_read(i);
else
dev_size = fd_dev->fd_dev_size;
return div_u64(dev_size - dev->dev_attrib.block_size,
dev->dev_attrib.block_size);
}
static int fd_init_prot(struct se_device *dev)
{
struct fd_dev *fd_dev = FD_DEV(dev);
struct file *prot_file, *file = fd_dev->fd_file;
struct inode *inode;
int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
char buf[FD_MAX_DEV_PROT_NAME];
if (!file) {
pr_err("Unable to locate fd_dev->fd_file\n");
return -ENODEV;
}
inode = file->f_mapping->host;
if (S_ISBLK(inode->i_mode)) {
pr_err("FILEIO Protection emulation only supported on"
" !S_ISBLK\n");
return -ENOSYS;
}
if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
flags &= ~O_DSYNC;
snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
fd_dev->fd_dev_name);
prot_file = filp_open(buf, flags, 0600);
if (IS_ERR(prot_file)) {
pr_err("filp_open(%s) failed\n", buf);
ret = PTR_ERR(prot_file);
return ret;
}
fd_dev->fd_prot_file = prot_file;
return 0;
}
static int fd_format_prot(struct se_device *dev)
{
unsigned char *buf;
int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
int ret;
if (!dev->dev_attrib.pi_prot_type) {
pr_err("Unable to format_prot while pi_prot_type == 0\n");
return -ENODEV;
}
buf = vzalloc(unit_size);
if (!buf) {
pr_err("Unable to allocate FILEIO prot buf\n");
return -ENOMEM;
}
pr_debug("Using FILEIO prot_length: %llu\n",
(unsigned long long)(dev->transport->get_blocks(dev) + 1) *
dev->prot_length);
memset(buf, 0xff, unit_size);
ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
buf, unit_size);
vfree(buf);
return ret;
}
static void fd_free_prot(struct se_device *dev)
{
struct fd_dev *fd_dev = FD_DEV(dev);
if (!fd_dev->fd_prot_file)
return;
filp_close(fd_dev->fd_prot_file, NULL);
fd_dev->fd_prot_file = NULL;
}
static struct sbc_ops fd_sbc_ops = {
.execute_rw = fd_execute_rw,
.execute_sync_cache = fd_execute_sync_cache,
.execute_write_same = fd_execute_write_same,
.execute_unmap = fd_execute_unmap,
};
static sense_reason_t
fd_parse_cdb(struct se_cmd *cmd)
{
return sbc_parse_cdb(cmd, &fd_sbc_ops);
}
static const struct target_backend_ops fileio_ops = {
.name = "fileio",
.inquiry_prod = "FILEIO",
.inquiry_rev = FD_VERSION,
.owner = THIS_MODULE,
.attach_hba = fd_attach_hba,
.detach_hba = fd_detach_hba,
.alloc_device = fd_alloc_device,
.configure_device = fd_configure_device,
.free_device = fd_free_device,
.parse_cdb = fd_parse_cdb,
.set_configfs_dev_params = fd_set_configfs_dev_params,
.show_configfs_dev_params = fd_show_configfs_dev_params,
.get_device_type = sbc_get_device_type,
.get_blocks = fd_get_blocks,
.init_prot = fd_init_prot,
.format_prot = fd_format_prot,
.free_prot = fd_free_prot,
.tb_dev_attrib_attrs = sbc_attrib_attrs,
};
static int __init fileio_module_init(void)
{
return transport_backend_register(&fileio_ops);
}
static void __exit fileio_module_exit(void)
{
target_backend_unregister(&fileio_ops);
}
MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
MODULE_AUTHOR("nab@Linux-iSCSI.org");
MODULE_LICENSE("GPL");
module_init(fileio_module_init);
module_exit(fileio_module_exit);