nvme: fix srcu locking on error return in nvme_get_ns_from_disk

[ Upstream commit 100c815cbd56480b3e31518475b04719c363614a ]

If we can't get a namespace don't leak the SRCU lock.  nvme_ioctl was
working around this, but nvme_pr_command wasn't handling this properly.
Just do what callers would usually expect.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Christoph Hellwig
2019-05-17 02:47:33 -07:00
committed by Greg Kroah-Hartman
parent c4e97af6bf
commit a6515af9b8

View File

@@ -1277,9 +1277,14 @@ static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk,
{
#ifdef CONFIG_NVME_MULTIPATH
if (disk->fops == &nvme_ns_head_ops) {
struct nvme_ns *ns;
*head = disk->private_data;
*srcu_idx = srcu_read_lock(&(*head)->srcu);
return nvme_find_path(*head);
ns = nvme_find_path(*head);
if (!ns)
srcu_read_unlock(&(*head)->srcu, *srcu_idx);
return ns;
}
#endif
*head = NULL;
@@ -1326,9 +1331,9 @@ static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx);
if (unlikely(!ns))
ret = -EWOULDBLOCK;
else
ret = nvme_ns_ioctl(ns, cmd, arg);
return -EWOULDBLOCK;
ret = nvme_ns_ioctl(ns, cmd, arg);
nvme_put_ns_from_disk(head, srcu_idx);
return ret;
}