From: Christoph Hellwig hch@lst.de
stable inclusion from linux-4.19.191 commit 587241f748424a7532b1cd9536b2128a47ee54a1
--------------------------------
commit 8b57251f9a91f5e5a599de7549915d2d226cc3af upstream.
Factor out a self-contained helper to just lookup a mddev by the dev_t "unit".
Cc: stable@vger.kernel.org Reviewed-by: Heming Zhao heming.zhao@suse.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Song Liu song@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/md/md.c | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c index 9cf8ed292befe..60682ba9ae556 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -584,6 +584,17 @@ void mddev_init(struct mddev *mddev) } EXPORT_SYMBOL_GPL(mddev_init);
+static struct mddev *mddev_find_locked(dev_t unit) +{ + struct mddev *mddev; + + list_for_each_entry(mddev, &all_mddevs, all_mddevs) + if (mddev->unit == unit) + return mddev; + + return NULL; +} + static struct mddev *mddev_find(dev_t unit) { struct mddev *mddev; @@ -611,13 +622,13 @@ static struct mddev *mddev_find_or_alloc(dev_t unit) spin_lock(&all_mddevs_lock);
if (unit) { - list_for_each_entry(mddev, &all_mddevs, all_mddevs) - if (mddev->unit == unit) { - mddev_get(mddev); - spin_unlock(&all_mddevs_lock); - kfree(new); - return mddev; - } + mddev = mddev_find_locked(unit); + if (mddev) { + mddev_get(mddev); + spin_unlock(&all_mddevs_lock); + kfree(new); + return mddev; + }
if (new) { list_add(&new->all_mddevs, &all_mddevs); @@ -643,12 +654,7 @@ static struct mddev *mddev_find_or_alloc(dev_t unit) return NULL; }
- is_free = 1; - list_for_each_entry(mddev, &all_mddevs, all_mddevs) - if (mddev->unit == dev) { - is_free = 0; - break; - } + is_free = !mddev_find_locked(dev); } new->unit = dev; new->md_minor = MINOR(dev);