[PATCH v4 16/18] btrfs: stop special-casing free space inodes in the delalloc accounting

[Tal Zussman]

Free space inodes never have delalloc or outstanding extents any more,
so they don't need to be kept off the root's delalloc inode list, out of
the outstanding extents tracepoint, or exempt from the delalloc metadata
release, which skipped the tree root since free space inodes are its
only inodes with data.

Assisted-by: LLM
Signed-off-by: Tal Zussman <tz2294@xxxxxxxxxxxx>
---
 fs/btrfs/btrfs_inode.h |  2 --
 fs/btrfs/inode.c       | 13 +++----------
 2 files changed, 3 insertions(+), 12 deletions(-)

diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index d1c014da52a3..f7aa0d145185 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -409,8 +409,6 @@ static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode,
 {
 	lockdep_assert_held(&inode->lock);
 	inode->outstanding_extents += mod;
-	if (btrfs_is_free_space_inode(inode))
-		return;
 	trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode),
 						  mod, inode->outstanding_extents);
 }
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 5a8f028b2a7d..e715b52fc60d 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2632,7 +2632,7 @@ void btrfs_set_delalloc_extent(struct btrfs_inode *inode, struct extent_state *s
 		 * and are therefore protected against concurrent calls of this
 		 * function and btrfs_clear_delalloc_extent().
 		 */
-		if (!btrfs_is_free_space_inode(inode) && prev_delalloc_bytes == 0)
+		if (prev_delalloc_bytes == 0)
 			btrfs_add_delalloc_inode(inode);
 	}
 
@@ -2676,13 +2676,7 @@ void btrfs_clear_delalloc_extent(struct btrfs_inode *inode,
 		btrfs_mod_outstanding_extents(inode, -num_extents);
 		spin_unlock(&inode->lock);
 
-		/*
-		 * We don't reserve metadata space for space cache inodes so we
-		 * don't need to call delalloc_release_metadata if there is an
-		 * error.
-		 */
-		if (bits & EXTENT_CLEAR_META_RESV &&
-		    root != fs_info->tree_root)
+		if (bits & EXTENT_CLEAR_META_RESV)
 			btrfs_delalloc_release_metadata(inode, len, true);
 
 		/* For sanity tests. */
@@ -2690,7 +2684,6 @@ void btrfs_clear_delalloc_extent(struct btrfs_inode *inode,
 			return;
 
 		if (!btrfs_is_data_reloc_root(root) &&
-		    !btrfs_is_free_space_inode(inode) &&
 		    !(state->state & EXTENT_NORESERVE) &&
 		    (bits & EXTENT_CLEAR_DATA_RESV))
 			btrfs_free_reserved_data_space_noquota(inode, len);
@@ -2708,7 +2701,7 @@ void btrfs_clear_delalloc_extent(struct btrfs_inode *inode,
 		 * and are therefore protected against concurrent calls of this
 		 * function and btrfs_set_delalloc_extent().
 		 */
-		if (!btrfs_is_free_space_inode(inode) && new_delalloc_bytes == 0) {
+		if (new_delalloc_bytes == 0) {
 			spin_lock(&root->delalloc_lock);
 			btrfs_del_delalloc_inode(inode);
 			spin_unlock(&root->delalloc_lock);

-- 
2.39.5