dm thin: don't allow messages to be sent to a pool target in READ_ONLY or FAIL mode

commit 2a7eaea02b upstream.

You can't modify the metadata in these modes.  It's better to fail these
messages immediately than let the block-manager deny write locks on
metadata blocks.  Otherwise these failed metadata changes will trigger
'needs_check' to get set in the metadata superblock -- requiring repair
using the thin_check utility.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Joe Thornber 2015-01-26 11:38:21 +00:00 committed by Greg Kroah-Hartman
parent 2811d3a0cf
commit b2c38d8fcf

View File

@ -2457,6 +2457,12 @@ static int pool_message(struct dm_target *ti, unsigned argc, char **argv)
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
if (get_pool_mode(pool) >= PM_READ_ONLY) {
DMERR("%s: unable to service pool target messages in READ_ONLY or FAIL mode",
dm_device_name(pool->pool_md));
return -EINVAL;
}
if (!strcasecmp(argv[0], "create_thin"))
r = process_create_thin_mesg(argc, argv, pool);