diff options
author | Alex Elder <elder@inktank.com> | 2012-07-03 16:01:19 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-01-17 08:46:49 -0800 |
commit | fefc034ae0af85c0b18fe209a1b6803d51880556 (patch) | |
tree | 34c6c986f149c8993dac84debc476d2a078fcc08 | |
parent | d741dc0695e62bcd1b7cfc7a8baa1f9e95fd07c7 (diff) |
rbd: increase maximum snapshot name length
(cherry picked from commit d4b125e9eb43babd14538ba61718e3db71a98d29)
Change RBD_MAX_SNAP_NAME_LEN to be based on NAME_MAX. That is a
practical limit for the length of a snapshot name (based on the
presence of a directory using the name under /sys/bus/rbd to
represent the snapshot).
The /sys entry is created by prefixing it with "snap_"; define that
prefix symbolically, and take its length into account in defining
the snapshot name length limit.
Enforce the limit in rbd_add_parse_args(). Also delete a dout()
call in that function that was not meant to be committed.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/block/rbd.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index b5e5ffec9c05..cd75b4d38e27 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -61,7 +61,10 @@ #define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */ -#define RBD_MAX_SNAP_NAME_LEN 32 +#define RBD_SNAP_DEV_NAME_PREFIX "snap_" +#define RBD_MAX_SNAP_NAME_LEN \ + (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1)) + #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */ #define RBD_MAX_OPT_LEN 1024 @@ -2073,7 +2076,7 @@ static int rbd_register_snap_dev(struct rbd_snap *snap, dev->type = &rbd_snap_device_type; dev->parent = parent; dev->release = rbd_snap_dev_release; - dev_set_name(dev, "snap_%s", snap->name); + dev_set_name(dev, "%s%s", RBD_SNAP_DEV_NAME_PREFIX, snap->name); dout("%s: registering device for snapshot %s\n", __func__, snap->name); ret = device_register(dev); @@ -2766,8 +2769,13 @@ static char *rbd_add_parse_args(struct rbd_device *rbd_dev, if (!rbd_dev->image_name) goto out_err; - /* Snapshot name is optional */ + /* Snapshot name is optional; default is to use "head" */ + len = next_token(&buf); + if (len > RBD_MAX_SNAP_NAME_LEN) { + err_ptr = ERR_PTR(-ENAMETOOLONG); + goto out_err; + } if (!len) { buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */ len = sizeof (RBD_SNAP_HEAD_NAME) - 1; @@ -2778,8 +2786,6 @@ static char *rbd_add_parse_args(struct rbd_device *rbd_dev, memcpy(snap_name, buf, len); *(snap_name + len) = '\0'; -dout(" SNAP_NAME is <%s>, len is %zd\n", snap_name, len); - return snap_name; out_err: |