From: Christoph Hellwig <hch@lst.de>
To: Jens Axboe <axboe@kernel.dk>
Cc: Tejun Heo <tj@kernel.org>, linux-block@vger.kernel.org
Subject: [PATCH 1/4] block: simplify the restart case in __blkdev_get
Date: Thu, 16 Jul 2020 16:33:07 +0200 [thread overview]
Message-ID: <20200716143310.473136-2-hch@lst.de> (raw)
In-Reply-To: <20200716143310.473136-1-hch@lst.de>
Insted of duplicating all the cleanup logic jump to the code that cleans
up anyway, and restart after that.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/block_dev.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)
diff --git a/fs/block_dev.c b/fs/block_dev.c
index a36d5b6907ea4e..376832250c8e91 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1517,7 +1517,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
int ret;
int partno;
int perm = 0;
- bool first_open = false;
+ bool first_open = false, need_restart;
if (mode & FMODE_READ)
perm |= MAY_READ;
@@ -1533,7 +1533,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
}
restart:
-
+ need_restart = false;
ret = -ENXIO;
disk = bdev_get_gendisk(bdev, &partno);
if (!disk)
@@ -1556,19 +1556,12 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
ret = 0;
if (disk->fops->open) {
ret = disk->fops->open(bdev, mode);
- if (ret == -ERESTARTSYS) {
- /* Lost a race with 'disk' being
- * deleted, try again.
- * See md.c
- */
- disk_put_part(bdev->bd_part);
- bdev->bd_part = NULL;
- bdev->bd_disk = NULL;
- mutex_unlock(&bdev->bd_mutex);
- disk_unblock_events(disk);
- put_disk_and_module(disk);
- goto restart;
- }
+ /*
+ * If we lost a race with 'disk' being deleted,
+ * try again. See md.c
+ */
+ if (ret == -ERESTARTSYS)
+ need_restart = true;
}
if (!ret) {
@@ -1647,6 +1640,8 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
mutex_unlock(&bdev->bd_mutex);
disk_unblock_events(disk);
put_disk_and_module(disk);
+ if (need_restart)
+ goto restart;
out:
return ret;
--
2.27.0
next prev parent reply other threads:[~2020-07-16 14:33 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-16 14:33 simplify block device claiming (resend) Christoph Hellwig
2020-07-16 14:33 ` Christoph Hellwig [this message]
2020-07-16 14:40 ` [PATCH 1/4] block: simplify the restart case in __blkdev_get Tejun Heo
2020-07-16 17:40 ` Hannes Reinecke
2020-07-16 14:33 ` [PATCH 2/4] block: refactor bd_start_claiming Christoph Hellwig
2020-07-16 14:41 ` Tejun Heo
2020-07-16 17:41 ` Hannes Reinecke
2020-07-16 14:33 ` [PATCH 3/4] block: use bd_prepare_to_claim directly in the loop driver Christoph Hellwig
2020-07-16 17:43 ` Hannes Reinecke
2020-07-16 14:33 ` [PATCH 4/4] block: integrate bd_start_claiming into __blkdev_get Christoph Hellwig
2020-07-16 15:02 ` Tejun Heo
2020-07-16 17:47 ` Hannes Reinecke
2020-07-16 15:37 ` simplify block device claiming (resend) Jens Axboe
-- strict thread matches above, loose matches on Subject: below --
2020-07-02 8:49 simplify block device claiming Christoph Hellwig
2020-07-02 8:49 ` [PATCH 1/4] block: simplify the restart case in __blkdev_get Christoph Hellwig
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