[PATCH v3 12/17] btrfs: remove BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE

[Tal Zussman]

Free space inodes no longer reserve data or delalloc space, as nothing
writes to them. Remove the flush mode and the special cases that
selected it.

Assisted-by: Claude:claude-fable-5-1
Signed-off-by: Tal Zussman <tz2294@xxxxxxxxxxxx>
---
 fs/btrfs/delalloc-space.c | 13 ++-----------
 fs/btrfs/space-info.c     |  2 --
 fs/btrfs/space-info.h     |  4 ----
 3 files changed, 2 insertions(+), 17 deletions(-)

diff --git a/fs/btrfs/delalloc-space.c b/fs/btrfs/delalloc-space.c
index d357ed7efd99..77781852e417 100644
--- a/fs/btrfs/delalloc-space.c
+++ b/fs/btrfs/delalloc-space.c
@@ -132,9 +132,7 @@ int btrfs_alloc_data_chunk_ondemand(const struct btrfs_inode *inode, u64 bytes)
 	/* Make sure bytes are sectorsize aligned */
 	bytes = ALIGN(bytes, fs_info->sectorsize);
 
-	if (btrfs_is_free_space_inode(inode))
-		flush = BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE;
-	else if (btrfs_is_zoned(fs_info) && btrfs_is_data_reloc_root(root))
+	if (btrfs_is_zoned(fs_info) && btrfs_is_data_reloc_root(root))
 		flush = BTRFS_RESERVE_FLUSH_ZONED_RELOCATION;
 
 	return btrfs_reserve_data_bytes(data_sinfo_for_inode(inode), bytes, flush);
@@ -155,8 +153,6 @@ int btrfs_check_data_free_space(struct btrfs_inode *inode,
 
 	if (noflush)
 		flush = BTRFS_RESERVE_NO_FLUSH;
-	else if (btrfs_is_free_space_inode(inode))
-		flush = BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE;
 
 	ret = btrfs_reserve_data_bytes(data_sinfo_for_inode(inode), len, flush);
 	if (ret < 0)
@@ -326,15 +322,10 @@ int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes,
 	int ret = 0;
 
 	/*
-	 * If we are a free space inode we need to not flush since we will be in
-	 * the middle of a transaction commit.  We also don't need the delalloc
-	 * mutex since we won't race with anybody.  We need this mostly to make
-	 * lockdep shut its filthy mouth.
-	 *
 	 * If we have a transaction open (can happen if we call truncate_block
 	 * from truncate), then we need FLUSH_LIMIT so we don't deadlock.
 	 */
-	if (noflush || btrfs_is_free_space_inode(inode)) {
+	if (noflush) {
 		flush = BTRFS_RESERVE_NO_FLUSH;
 	} else {
 		if (current->journal_info)
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 39a28e1bec8a..01018152c054 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -1704,7 +1704,6 @@ static int handle_reserve_ticket(struct btrfs_space_info *space_info,
 						evict_flush_states,
 						ARRAY_SIZE(evict_flush_states));
 		break;
-	case BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE:
 	case BTRFS_RESERVE_FLUSH_ZONED_RELOCATION:
 		priority_reclaim_data_space(space_info, ticket);
 		break;
@@ -1968,7 +1967,6 @@ int btrfs_reserve_data_bytes(struct btrfs_space_info *space_info, u64 bytes,
 	int ret;
 
 	ASSERT(flush == BTRFS_RESERVE_FLUSH_DATA ||
-	       flush == BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE ||
 	       flush == BTRFS_RESERVE_FLUSH_ZONED_RELOCATION ||
 	       flush == BTRFS_RESERVE_NO_FLUSH, "flush=%d", flush);
 	ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_DATA,
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index aa836e8a9d4a..d0130c8ba3dd 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -66,7 +66,6 @@ enum btrfs_reserve_flush_enum {
 	 * Can be interrupted by a fatal signal.
 	 */
 	BTRFS_RESERVE_FLUSH_DATA,
-	BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE,
 	BTRFS_RESERVE_FLUSH_ALL,
 
 	/*
@@ -82,9 +81,6 @@ enum btrfs_reserve_flush_enum {
 	 * priority flushing for this, because otherwise we can deadlock on
 	 * waiting for a ticket, that cannot be granted, because we cannot do
 	 * any allocations.
-	 *
-	 * Apart from being specific to zoned relocation, it is equal to
-	 * BTRFS_FLUSH_FREE_SPACE_INODE.
 	 */
 	BTRFS_RESERVE_FLUSH_ZONED_RELOCATION,
 

-- 
2.39.5