On Fri, May 15, 2020 at 02:01:41PM +0800, Qu Wenruo wrote:
> There are a lot of root owner check in btrfs_truncate_inode_items()
> like:
>
> if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state) ||
> root == fs_info->tree_root)
>
> But considering that, there are only those trees can have INODE_ITEMs:
> - tree root (For v1 space cache)
> - subvolume trees
> - tree reloc trees
> - data reloc tree
> - log trees
>
> And since subvolume/tree reloc/data reloc trees all have SHAREABLE bit,
> and we're checking tree root manually, so above check is just excluding
> log trees.
>
> This patch will replace two of such checks to a much simpler one:
>
> if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
>
> This would merge btrfs_drop_extent_cache() and lock_extent_bits() call
> into the same if branch.
>
> Finally replace ALIGN() with round_up(), as I'm always bad at determing
> the alignement direction.
Alert
>
> Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
> ---
> fs/btrfs/inode.c | 21 +++++++++------------
> 1 file changed, 9 insertions(+), 12 deletions(-)
>
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index a6c26c10ffc5..ae6b47edabc5 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -4121,20 +4121,18 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
> return -ENOMEM;
> path->reada = READA_BACK;
>
> - if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
> + if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
> + /*
> + * We want to drop from the next block forward in case this
> + * new size is not block aligned since we will be keeping the
> + * last block of the extent just the way it is.
> + */
The comment is misplaced, it belongs to the 'drop extent cache' part
> lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, (u64)-1,
> &cached_state);
> -
> - /*
> - * We want to drop from the next block forward in case this new size is
> - * not block aligned since we will be keeping the last block of the
> - * extent just the way it is.
> - */
> - if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state) ||
> - root == fs_info->tree_root)
> - btrfs_drop_extent_cache(BTRFS_I(inode), ALIGN(new_size,
here.
Regarding ALIGN -> round_up, please don't put such unrelated changes to
one patch.
