dm: return early from dm_pr_call() if DM device is suspended

[ Upstream commit e120a5f1e78fab6223544e425015f393d90d6f0d ]

Otherwise PR ops may be issued while the broader DM device is being
reconfigured, etc.

Fixes: 9c72bad1f31a ("dm: call PR reserve/unreserve on each underlying device")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 3644942..41d2e12 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2911,6 +2911,11 @@ static int dm_call_pr(struct block_device *bdev, iterate_devices_callout_fn fn,
                goto out;
        ti = dm_table_get_target(table, 0);
 
+       if (dm_suspended_md(md)) {
+               ret = -EAGAIN;
+               goto out;
+       }
+
        ret = -EINVAL;
        if (!ti->type->iterate_devices)
                goto out;