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linux/drivers/target/target_core_file.c

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/*******************************************************************************
* 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 <linux/uio.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);
if (target_configure_unmap_from_queue(&dev->dev_attrib, q))
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)
{
call_rcu(&dev->rcu_head, fd_dev_call_rcu);
}
static void fd_destroy_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;
}
}
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, 0);
else
ret = vfs_iter_read(fd, &iter, &pos, 0);
if (is_write) {
if (ret < 0 || ret != data_length) {
pr_err("%s() write returned %d\n", __func__, ret);
if (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);
if (ret >= 0)
ret = -EINVAL;
}
} else {
if (ret < 0) {
pr_err("%s() returned %d for non S_ISBLK\n",
__func__, ret);
} else if (ret != data_length) {
/*
* Short read case:
* Probably some one truncate file under us.
* We must explicitly zero sg-pages to prevent
* expose uninizialized pages to userspace.
*/
if (ret < data_length)
ret += iov_iter_zero(data_length - ret, &iter);
else
ret = -EINVAL;
}
}
}
kfree(bvec);
return ret;
}
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, 0);
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);
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;
struct se_device *dev = cmd->se_dev;
ret = blkdev_issue_discard(bdev,
target_to_linux_sector(dev, lba),
target_to_linux_sector(dev, 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 limitation\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 &&
dev->dev_attrib.pi_prot_verify) {
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 &&
dev->dev_attrib.pi_prot_verify) {
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;
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,
.destroy_device = fd_destroy_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);
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