diff options
| -rw-r--r-- | fs/btrfs/direct-io.c | 44 |
1 files changed, 32 insertions, 12 deletions
diff --git a/fs/btrfs/direct-io.c b/fs/btrfs/direct-io.c index ea7f918b1c45..4a5f9b2632f2 100644 --- a/fs/btrfs/direct-io.c +++ b/fs/btrfs/direct-io.c @@ -40,11 +40,21 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend, struct btrfs_ordered_extent *ordered; int ret = 0; + /* Direct lock must be taken before the extent lock. */ + if (nowait) { + if (!try_lock_dio_extent(io_tree, lockstart, lockend, cached_state)) + return -EAGAIN; + } else { + lock_dio_extent(io_tree, lockstart, lockend, cached_state); + } + while (1) { if (nowait) { if (!try_lock_extent(io_tree, lockstart, lockend, - cached_state)) - return -EAGAIN; + cached_state)) { + ret = -EAGAIN; + break; + } } else { lock_extent(io_tree, lockstart, lockend, cached_state); } @@ -120,6 +130,8 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend, cond_resched(); } + if (ret) + unlock_dio_extent(io_tree, lockstart, lockend, cached_state); return ret; } @@ -546,8 +558,9 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start, } if (unlock_extents) - unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend, - &cached_state); + clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, + EXTENT_LOCKED | EXTENT_DIO_LOCKED, + &cached_state); else free_extent_state(cached_state); @@ -572,8 +585,13 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start, return 0; unlock_err: - unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend, - &cached_state); + /* + * Don't use EXTENT_LOCK_BITS here in case we extend it later and forget + * to update this, be explicit that we expect EXTENT_LOCKED and + * EXTENT_DIO_LOCKED to be set here, and so that's what we're clearing. + */ + clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, + EXTENT_LOCKED | EXTENT_DIO_LOCKED, &cached_state); err: if (dio_data->data_space_reserved) { btrfs_free_reserved_data_space(BTRFS_I(inode), @@ -596,8 +614,8 @@ static int btrfs_dio_iomap_end(struct inode *inode, loff_t pos, loff_t length, if (!write && (iomap->type == IOMAP_HOLE)) { /* If reading from a hole, unlock and return */ - unlock_extent(&BTRFS_I(inode)->io_tree, pos, pos + length - 1, - NULL); + clear_extent_bit(&BTRFS_I(inode)->io_tree, pos, pos + length - 1, + EXTENT_LOCKED | EXTENT_DIO_LOCKED, NULL); return 0; } @@ -608,8 +626,9 @@ static int btrfs_dio_iomap_end(struct inode *inode, loff_t pos, loff_t length, btrfs_finish_ordered_extent(dio_data->ordered, NULL, pos, length, false); else - unlock_extent(&BTRFS_I(inode)->io_tree, pos, - pos + length - 1, NULL); + clear_extent_bit(&BTRFS_I(inode)->io_tree, pos, + pos + length - 1, + EXTENT_LOCKED | EXTENT_DIO_LOCKED, NULL); ret = -ENOTBLK; } if (write) { @@ -641,8 +660,9 @@ static void btrfs_dio_end_io(struct btrfs_bio *bbio) dip->file_offset, dip->bytes, !bio->bi_status); } else { - unlock_extent(&inode->io_tree, dip->file_offset, - dip->file_offset + dip->bytes - 1, NULL); + clear_extent_bit(&inode->io_tree, dip->file_offset, + dip->file_offset + dip->bytes - 1, + EXTENT_LOCKED | EXTENT_DIO_LOCKED, NULL); } bbio->bio.bi_private = bbio->private; |