[PATCH 5/8] block: split __blkdev_put

Christoph Hellwig
2021-05-12T06:19:19Z

Split __blkdev_put into one helper for the whole device, and one for
partitions as well as another shared helper for flushing the block
device inode mapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/block_dev.c | 58 ++++++++++++++++++++++++++++----------------------
1 file changed, 32 insertions(+), 26 deletions(-)

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 59cdcdb97e3d..4bcab845ac05 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1234,7 +1234,13 @@ void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk)
EXPORT_SYMBOL_GPL(bd_unlink_disk_holder);
#endif

-static void __blkdev_put(struct block_device *bdev, fmode_t mode);
+static void blkdev_flush_mapping(struct block_device *bdev)
+{
+ WARN_ON_ONCE(bdev->bd_holders);
+ sync_blockdev(bdev);
+ kill_bdev(bdev);
+ bdev_write_inode(bdev);
+}

int bdev_disk_changed(struct block_device *bdev, bool invalidate)
{
@@ -1313,6 +1319,14 @@ static int blkdev_get_whole(struct block_device *bdev, fmode_t mode)
return 0;;
}

+static void blkdev_put_whole(struct block_device *bdev, fmode_t mode)
+{
+ if (!--bdev->bd_openers)
+ blkdev_flush_mapping(bdev);
+ if (bdev->bd_disk->fops->release)
+ bdev->bd_disk->fops->release(bdev->bd_disk, mode);
+}
+
static int blkdev_get_part(struct block_device *part, fmode_t mode)
{
struct gendisk *disk = part->bd_disk;
@@ -1340,12 +1354,24 @@ static int blkdev_get_part(struct block_device *part, fmode_t mode)
return 0;

out_blkdev_put:
- __blkdev_put(whole, mode);
+ blkdev_put_whole(whole, mode);
out_put_whole:
bdput(whole);
return ret;
}

+static void blkdev_put_part(struct block_device *part, fmode_t mode)
+{
+ struct block_device *whole = bdev_whole(part);
+
+ if (--part->bd_openers)
+ return;
+ blkdev_flush_mapping(part);
+ whole->bd_part_count--;
+ blkdev_put_whole(whole, mode);
+ bdput(whole);
+}
+
struct block_device *blkdev_get_no_open(dev_t dev)
{
struct block_device *bdev;
@@ -1543,29 +1569,6 @@ static int blkdev_open(struct inode * inode, struct file * filp)
return 0;
}

-static void __blkdev_put(struct block_device *bdev, fmode_t mode)
-{
- struct gendisk *disk = bdev->bd_disk;
- struct block_device *victim = NULL;
-
- if (!--bdev->bd_openers) {
- WARN_ON_ONCE(bdev->bd_holders);
- sync_blockdev(bdev);
- kill_bdev(bdev);
- bdev_write_inode(bdev);
- if (bdev_is_partition(bdev))
- victim = bdev_whole(bdev);
- }
-
- if (!bdev_is_partition(bdev) && disk->fops->release)
- disk->fops->release(disk, mode);
- if (victim) {
- victim->bd_part_count--;
- __blkdev_put(victim, mode);
- bdput(victim);
- }
-}
-
void blkdev_put(struct block_device *bdev, fmode_t mode)
{
struct gendisk *disk = bdev->bd_disk;
@@ -1619,7 +1622,10 @@ void blkdev_put(struct block_device *bdev, fmode_t mode)
*/
disk_flush_events(disk, DISK_EVENT_MEDIA_CHANGE);

- __blkdev_put(bdev, mode);
+ if (bdev_is_partition(bdev))
+ blkdev_put_part(bdev, mode);
+ else
+ blkdev_put_whole(bdev, mode);
mutex_unlock(&disk->open_mutex);

blkdev_put_no_open(bdev);
--
2.30.2