block: remove bdev_handle completely

We just need to use the holder to indicate whether a block device open
was exclusive or not. We did use to do that before but had to give that
up once we switched to struct bdev_handle. Before struct bdev_handle we
only stashed stuff in file->private_data if this was an exclusive open
but after struct bdev_handle we always set file->private_data to a
struct bdev_handle and so we had to use bdev_handle->mode or
bdev_handle->holder. Now that we don't use struct bdev_handle anymore we
can revert back to the old behavior.

Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-32-adbd023e19cc@kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

1 files changed, 10 insertions, 11 deletions

diff --git a/block/fops.c b/block/fops.c
index aab9b89e4c77..029e787f0119 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -569,18 +569,17 @@ static int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
 blk_mode_t file_to_blk_mode(struct file *file)
 {
 	blk_mode_t mode = 0;
-	struct bdev_handle *handle = file->private_data;
 
 	if (file->f_mode & FMODE_READ)
 		mode |= BLK_OPEN_READ;
 	if (file->f_mode & FMODE_WRITE)
 		mode |= BLK_OPEN_WRITE;
 	/*
-	 * do_dentry_open() clears O_EXCL from f_flags, use handle->mode to
-	 * determine whether the open was exclusive for already open files.
+	 * do_dentry_open() clears O_EXCL from f_flags, use file->private_data
+	 * to determine whether the open was exclusive for already open files.
 	 */
-	if (handle)
-		mode |= handle->mode & BLK_OPEN_EXCL;
+	if (file->private_data)
+		mode |= BLK_OPEN_EXCL;
 	else if (file->f_flags & O_EXCL)
 		mode |= BLK_OPEN_EXCL;
 	if (file->f_flags & O_NDELAY)
@@ -601,12 +600,13 @@ static int blkdev_open(struct inode *inode, struct file *filp)
 {
 	struct block_device *bdev;
 	blk_mode_t mode;
-	void *holder;
 	int ret;
 
 	mode = file_to_blk_mode(filp);
-	holder = mode & BLK_OPEN_EXCL ? filp : NULL;
-	ret = bdev_permission(inode->i_rdev, mode, holder);
+	/* Use the file as the holder. */
+	if (mode & BLK_OPEN_EXCL)
+		filp->private_data = filp;
+	ret = bdev_permission(inode->i_rdev, mode, filp->private_data);
 	if (ret)
 		return ret;
 
@@ -614,7 +614,7 @@ static int blkdev_open(struct inode *inode, struct file *filp)
 	if (!bdev)
 		return -ENXIO;
 
-	ret = bdev_open(bdev, mode, holder, NULL, filp);
+	ret = bdev_open(bdev, mode, filp->private_data, NULL, filp);
 	if (ret)
 		blkdev_put_no_open(bdev);
 	return ret;
@@ -622,8 +622,7 @@ static int blkdev_open(struct inode *inode, struct file *filp)
 
 static int blkdev_release(struct inode *inode, struct file *filp)
 {
-	if (filp->private_data)
-		bdev_release(filp);
+	bdev_release(filp);
 	return 0;
 }