[PATCH 9/9] btrfs: unlock extents in ->iomap_end() for DIO reads

[Goldwyn Rodrigues <rgoldwyn@suse.de>]

From: Goldwyn Rodrigues <rgoldwyn@suse.com>

Simplify the locking and unlocking of extents and unlock the extents in
->iomap_end() instead of endio routine.

This makes sure we do not have locked extents in case of device error.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
---
 fs/btrfs/inode.c | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 4ccd2a23b1b4..3e8e91d202d2 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7241,18 +7241,13 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
 		unlock_extents = true;
 		/* Recalc len in case the new em is smaller than requested */
 		len = min(len, em->len - (start - em->start));
-	} else if (em->block_start == EXTENT_MAP_HOLE ||
-			test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
-		/* Unlock in case of direct reading from a hole */
-		unlock_extents = true;
-	} else {
+	} else if (start + len < lockend) {
 		/*
 		 * We need to unlock only the end area that we aren't using.
 		 * The rest is going to be unlocked by the endio routine.
 		 */
 		lockstart = start + len;
-		if (lockstart < lockend)
-			unlock_extents = true;
+		unlock_extents = true;
 	}
 
 	if (unlock_extents)
@@ -7299,8 +7294,10 @@ static int btrfs_dio_iomap_end(struct inode *inode, loff_t pos, loff_t length,
 	struct btrfs_iomap *btrfs_iomap = iomap->private;
 	int ret = 0;
 
-	if (!(flags & IOMAP_WRITE))
+	if (!(flags & IOMAP_WRITE)) {
+		unlock_extent(&BTRFS_I(inode)->io_tree, pos, pos + length - 1);
 		return 0;
+	}
 
 	if (btrfs_iomap->submitted_bytes < length) {
 		__endio_write_update_ordered(inode,
@@ -7661,10 +7658,7 @@ static void btrfs_endio_direct_read(struct bio *bio)
 	if (dip->flags & BTRFS_DIO_ORIG_BIO_SUBMITTED)
 		err = btrfs_subio_endio_read(inode, io_bio, err);
 
-	unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
-		      dip->logical_offset + dip->bytes - 1);
 	dio_bio = dip->dio_bio;
-
 	kfree(dip);
 
 	btrfs_io_bio_free_csum(io_bio);
-- 
2.25.0