target/iblock: Add parameter to specify read-only devices

see https://bugzilla.redhat.com/show_bug.cgi?id=818855

Adds a parameter so read-only block devices may be registered as
LIO backstores.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Andy Grover 2012-06-07 10:38:51 -07:00 committed by Nicholas Bellinger
parent 7acd570706
commit 44bfd01850
2 changed files with 29 additions and 7 deletions

View File

@ -96,6 +96,7 @@ static struct se_device *iblock_create_virtdevice(
struct request_queue *q;
struct queue_limits *limits;
u32 dev_flags = 0;
fmode_t mode;
int ret = -EINVAL;
if (!ib_dev) {
@ -117,8 +118,11 @@ static struct se_device *iblock_create_virtdevice(
pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
ib_dev->ibd_udev_path);
bd = blkdev_get_by_path(ib_dev->ibd_udev_path,
FMODE_WRITE|FMODE_READ|FMODE_EXCL, ib_dev);
mode = FMODE_READ|FMODE_EXCL;
if (!ib_dev->ibd_readonly)
mode |= FMODE_WRITE;
bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev);
if (IS_ERR(bd)) {
ret = PTR_ERR(bd);
goto failed;
@ -323,11 +327,12 @@ static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range)
}
enum {
Opt_udev_path, Opt_force, Opt_err
Opt_udev_path, Opt_readonly, Opt_force, Opt_err
};
static match_table_t tokens = {
{Opt_udev_path, "udev_path=%s"},
{Opt_readonly, "readonly=%d"},
{Opt_force, "force=%d"},
{Opt_err, NULL}
};
@ -340,6 +345,7 @@ static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
char *orig, *ptr, *arg_p, *opts;
substring_t args[MAX_OPT_ARGS];
int ret = 0, token;
unsigned long tmp_readonly;
opts = kstrdup(page, GFP_KERNEL);
if (!opts)
@ -372,6 +378,22 @@ static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
ib_dev->ibd_udev_path);
ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
break;
case Opt_readonly:
arg_p = match_strdup(&args[0]);
if (!arg_p) {
ret = -ENOMEM;
break;
}
ret = strict_strtoul(arg_p, 0, &tmp_readonly);
kfree(arg_p);
if (ret < 0) {
pr_err("strict_strtoul() failed for"
" readonly=\n");
goto out;
}
ib_dev->ibd_readonly = tmp_readonly;
pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
break;
case Opt_force:
break;
default:
@ -411,11 +433,10 @@ static ssize_t iblock_show_configfs_dev_params(
if (bd)
bl += sprintf(b + bl, "iBlock device: %s",
bdevname(bd, buf));
if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) {
bl += sprintf(b + bl, " UDEV PATH: %s\n",
if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH)
bl += sprintf(b + bl, " UDEV PATH: %s",
ibd->ibd_udev_path);
} else
bl += sprintf(b + bl, "\n");
bl += sprintf(b + bl, " readonly: %d\n", ibd->ibd_readonly);
bl += sprintf(b + bl, " ");
if (bd) {

View File

@ -18,6 +18,7 @@ struct iblock_dev {
u32 ibd_flags;
struct bio_set *ibd_bio_set;
struct block_device *ibd_bd;
bool ibd_readonly;
} ____cacheline_aligned;
#endif /* TARGET_CORE_IBLOCK_H */