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); -- 2.25.1