Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (25 commits)
  btrfs: fix uninitialized variable warning
  btrfs: add helper for fs_info->closing
  Btrfs: add mount -o inode_cache
  btrfs: scrub: add explicit plugging
  btrfs: use btrfs_ino to access inode number
  Btrfs: don't save the inode cache if we are deleting this root
  btrfs: false BUG_ON when degraded
  Btrfs: don't save the inode cache in non-FS roots
  Btrfs: make sure we don't overflow the free space cache crc page
  Btrfs: fix uninit variable in the delayed inode code
  btrfs: scrub: don't reuse bios and pages
  Btrfs: leave spinning on lookup and map the leaf
  Btrfs: check for duplicate entries in the free space cache
  Btrfs: don't try to allocate from a block group that doesn't have enough space
  Btrfs: don't always do readahead
  Btrfs: try not to sleep as much when doing slow caching
  Btrfs: kill BTRFS_I(inode)->block_group
  Btrfs: don't look at the extent buffer level 3 times in a row
  Btrfs: map the node block when looking for readahead targets
  Btrfs: set range_start to the right start in count_range_bits
  ...

1 files changed, 32 insertions, 2 deletions

diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index 3262cd17a12..b4087e0fa87 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -38,6 +38,9 @@ static int caching_kthread(void *data)
 	int slot;
 	int ret;
 
+	if (!btrfs_test_opt(root, INODE_MAP_CACHE))
+		return 0;
+
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
@@ -59,8 +62,7 @@ again:
 		goto out;
 
 	while (1) {
-		smp_mb();
-		if (fs_info->closing)
+		if (btrfs_fs_closing(fs_info))
 			goto out;
 
 		leaf = path->nodes[0];
@@ -141,6 +143,9 @@ static void start_caching(struct btrfs_root *root)
 	int ret;
 	u64 objectid;
 
+	if (!btrfs_test_opt(root, INODE_MAP_CACHE))
+		return;
+
 	spin_lock(&root->cache_lock);
 	if (root->cached != BTRFS_CACHE_NO) {
 		spin_unlock(&root->cache_lock);
@@ -178,6 +183,9 @@ static void start_caching(struct btrfs_root *root)
 
 int btrfs_find_free_ino(struct btrfs_root *root, u64 *objectid)
 {
+	if (!btrfs_test_opt(root, INODE_MAP_CACHE))
+		return btrfs_find_free_objectid(root, objectid);
+
 again:
 	*objectid = btrfs_find_ino_for_alloc(root);
 
@@ -201,6 +209,10 @@ void btrfs_return_ino(struct btrfs_root *root, u64 objectid)
 {
 	struct btrfs_free_space_ctl *ctl = root->free_ino_ctl;
 	struct btrfs_free_space_ctl *pinned = root->free_ino_pinned;
+
+	if (!btrfs_test_opt(root, INODE_MAP_CACHE))
+		return;
+
 again:
 	if (root->cached == BTRFS_CACHE_FINISHED) {
 		__btrfs_add_free_space(ctl, objectid, 1);
@@ -250,6 +262,9 @@ void btrfs_unpin_free_ino(struct btrfs_root *root)
 	struct rb_node *n;
 	u64 count;
 
+	if (!btrfs_test_opt(root, INODE_MAP_CACHE))
+		return;
+
 	while (1) {
 		n = rb_first(rbroot);
 		if (!n)
@@ -388,9 +403,24 @@ int btrfs_save_ino_cache(struct btrfs_root *root,
 	int prealloc;
 	bool retry = false;
 
+	/* only fs tree and subvol/snap needs ino cache */
+	if (root->root_key.objectid != BTRFS_FS_TREE_OBJECTID &&
+	    (root->root_key.objectid < BTRFS_FIRST_FREE_OBJECTID ||
+	     root->root_key.objectid > BTRFS_LAST_FREE_OBJECTID))
+		return 0;
+
+	/* Don't save inode cache if we are deleting this root */
+	if (btrfs_root_refs(&root->root_item) == 0 &&
+	    root != root->fs_info->tree_root)
+		return 0;
+
+	if (!btrfs_test_opt(root, INODE_MAP_CACHE))
+		return 0;
+
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
+
 again:
 	inode = lookup_free_ino_inode(root, path);
 	if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {