target/file: Add DIF protection init/format support

This patch adds support for DIF protection init/format support into
the FILEIO backend.

It involves using a seperate $FILE.protection for storing PI that is
opened via fd_init_prot() using the common pi_prot_type attribute.
The actual formatting of the protection is done via fd_format_prot()
using the common pi_prot_format attribute, that will populate the
initial PI data based upon the currently configured pi_prot_type.

Based on original FILEIO code from Sagi.

v1 changes:
  - Fix sparse warnings in fd_init_format_buf (Fengguang)

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Nicholas Bellinger 2014-01-18 09:32:56 +00:00
parent ecebbf6ccb
commit 0f5e2ec46d
2 changed files with 141 additions and 0 deletions

View file

@ -700,6 +700,140 @@ static sector_t fd_get_blocks(struct se_device *dev)
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 void fd_init_format_buf(struct se_device *dev, unsigned char *buf,
u32 unit_size, u32 *ref_tag, u16 app_tag,
bool inc_reftag)
{
unsigned char *p = buf;
int i;
for (i = 0; i < unit_size; i += dev->prot_length) {
*((u16 *)&p[0]) = 0xffff;
*((__be16 *)&p[2]) = cpu_to_be16(app_tag);
*((__be32 *)&p[4]) = cpu_to_be32(*ref_tag);
if (inc_reftag)
(*ref_tag)++;
p += dev->prot_length;
}
}
static int fd_format_prot(struct se_device *dev)
{
struct fd_dev *fd_dev = FD_DEV(dev);
struct file *prot_fd = fd_dev->fd_prot_file;
sector_t prot_length, prot;
unsigned char *buf;
loff_t pos = 0;
u32 ref_tag = 0;
int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
int rc, ret = 0, size, len;
bool inc_reftag = false;
if (!dev->dev_attrib.pi_prot_type) {
pr_err("Unable to format_prot while pi_prot_type == 0\n");
return -ENODEV;
}
if (!prot_fd) {
pr_err("Unable to locate fd_dev->fd_prot_file\n");
return -ENODEV;
}
switch (dev->dev_attrib.pi_prot_type) {
case TARGET_DIF_TYPE3_PROT:
ref_tag = 0xffffffff;
break;
case TARGET_DIF_TYPE2_PROT:
case TARGET_DIF_TYPE1_PROT:
inc_reftag = true;
break;
default:
break;
}
buf = vzalloc(unit_size);
if (!buf) {
pr_err("Unable to allocate FILEIO prot buf\n");
return -ENOMEM;
}
prot_length = (dev->transport->get_blocks(dev) + 1) * dev->prot_length;
size = prot_length;
pr_debug("Using FILEIO prot_length: %llu\n",
(unsigned long long)prot_length);
for (prot = 0; prot < prot_length; prot += unit_size) {
fd_init_format_buf(dev, buf, unit_size, &ref_tag, 0xffff,
inc_reftag);
len = min(unit_size, size);
rc = kernel_write(prot_fd, buf, len, pos);
if (rc != len) {
pr_err("vfs_write to prot file failed: %d\n", rc);
ret = -ENODEV;
goto out;
}
pos += len;
size -= len;
}
out:
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,
@ -730,6 +864,9 @@ static struct se_subsystem_api fileio_template = {
.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,
};
static int __init fileio_module_init(void)

View file

@ -4,6 +4,7 @@
#define FD_VERSION "4.0"
#define FD_MAX_DEV_NAME 256
#define FD_MAX_DEV_PROT_NAME FD_MAX_DEV_NAME + 16
#define FD_DEVICE_QUEUE_DEPTH 32
#define FD_MAX_DEVICE_QUEUE_DEPTH 128
#define FD_BLOCKSIZE 512
@ -15,6 +16,8 @@
#define FBDF_HAS_PATH 0x01
#define FBDF_HAS_SIZE 0x02
#define FDBD_HAS_BUFFERED_IO_WCE 0x04
#define FDBD_FORMAT_UNIT_SIZE 2048
struct fd_dev {
struct se_device dev;
@ -29,6 +32,7 @@ struct fd_dev {
u32 fd_block_size;
unsigned long long fd_dev_size;
struct file *fd_file;
struct file *fd_prot_file;
/* FILEIO HBA device is connected to */
struct fd_host *fd_host;
} ____cacheline_aligned;