nvme: fix srcu locking on error return in nvme_get_ns_from_disk

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>
This commit is contained in:
Christoph Hellwig 2019-05-17 02:47:33 -07:00 committed by Keith Busch
parent 6fa0321a96
commit 100c815cbd

View File

@ -1361,9 +1361,14 @@ static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk,
{ {
#ifdef CONFIG_NVME_MULTIPATH #ifdef CONFIG_NVME_MULTIPATH
if (disk->fops == &nvme_ns_head_ops) { if (disk->fops == &nvme_ns_head_ops) {
struct nvme_ns *ns;
*head = disk->private_data; *head = disk->private_data;
*srcu_idx = srcu_read_lock(&(*head)->srcu); *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 #endif
*head = NULL; *head = NULL;
@ -1410,9 +1415,9 @@ static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx); ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx);
if (unlikely(!ns)) if (unlikely(!ns))
ret = -EWOULDBLOCK; return -EWOULDBLOCK;
else
ret = nvme_ns_ioctl(ns, cmd, arg); ret = nvme_ns_ioctl(ns, cmd, arg);
nvme_put_ns_from_disk(head, srcu_idx); nvme_put_ns_from_disk(head, srcu_idx);
return ret; return ret;
} }