From 63c34cb4c6dddd7899a14ed0a11b208a41e9c85c Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Tue, 15 Mar 2022 15:22:41 +0000 Subject: btrfs: add and use helper to assert an inode range is clean We have four different scenarios where we don't expect to find ordered extents after locking a file range: 1) During plain fallocate; 2) During hole punching; 3) During zero range; 4) During reflinks (both cloning and deduplication). This is because in all these cases we follow the pattern: 1) Lock the inode's VFS lock in exclusive mode; 2) Lock the inode's i_mmap_lock in exclusive node, to serialize with mmap writes; 3) Flush delalloc in a file range and wait for all ordered extents to complete - both done through btrfs_wait_ordered_range(); 4) Lock the file range in the inode's io_tree. So add a helper that asserts that we don't have ordered extents for a given range. Make the four scenarios listed above use this helper after locking the respective file range. Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/inode.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 31ccb82157c2..c4b68be7edd7 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -11261,6 +11261,41 @@ void btrfs_update_inode_bytes(struct btrfs_inode *inode, spin_unlock(&inode->lock); } +/** + * Verify that there are no ordered extents for a given file range. + * + * @inode: The target inode. + * @start: Start offset of the file range, should be sector size aligned. + * @end: End offset (inclusive) of the file range, its value +1 should be + * sector size aligned. + * + * This should typically be used for cases where we locked an inode's VFS lock in + * exclusive mode, we have also locked the inode's i_mmap_lock in exclusive mode, + * we have flushed all delalloc in the range, we have waited for all ordered + * extents in the range to complete and finally we have locked the file range in + * the inode's io_tree. + */ +void btrfs_assert_inode_range_clean(struct btrfs_inode *inode, u64 start, u64 end) +{ + struct btrfs_root *root = inode->root; + struct btrfs_ordered_extent *ordered; + + if (!IS_ENABLED(CONFIG_BTRFS_ASSERT)) + return; + + ordered = btrfs_lookup_first_ordered_range(inode, start, end + 1 - start); + if (ordered) { + btrfs_err(root->fs_info, +"found unexpected ordered extent in file range [%llu, %llu] for inode %llu root %llu (ordered range [%llu, %llu])", + start, end, btrfs_ino(inode), root->root_key.objectid, + ordered->file_offset, + ordered->file_offset + ordered->num_bytes - 1); + btrfs_put_ordered_extent(ordered); + } + + ASSERT(ordered == NULL); +} + static const struct inode_operations btrfs_dir_inode_operations = { .getattr = btrfs_getattr, .lookup = btrfs_lookup, -- cgit v1.2.3