From: Josef Bacik <josef@toxicpanda.com>
Date: Fri, 14 Feb 2020 16:11:41 -0500
Git-commit: 0e996e7fcf2e3a7a5d13b0ed5f9cebc551bd94ba
Patch-mainline: 5.7-rc1
References: bsc#1176019
Subject: [PATCH] btrfs: move ino_cache_inode dropping out of
 btrfs_free_fs_root

We are going to make root life be controlled soley by refcounting, and
inodes will be one of the things that hold a ref on the root.  This
means we need to handle dropping the ino_cache_inode outside of the root
freeing logic, so move it into btrfs_drop_and_free_fs_root() so it is
cleaned up properly on unmount.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/disk-io.c     | 5 ++++-
 fs/btrfs/transaction.c | 4 ++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 56cad6a51a7d..37418d1d0820 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3912,12 +3912,15 @@ void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
 		__btrfs_remove_free_space_cache(root->free_ino_pinned);
 	if (root->free_ino_ctl)
 		__btrfs_remove_free_space_cache(root->free_ino_ctl);
+	if (root->ino_cache_inode) {
+		iput(root->ino_cache_inode);
+		root->ino_cache_inode = NULL;
+	}
 	btrfs_free_fs_root(root);
 }
 
 void btrfs_free_fs_root(struct btrfs_root *root)
 {
-	iput(root->ino_cache_inode);
 	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
 	if (root->anon_dev)
 		free_anon_bdev(root->anon_dev);
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 5939bca9d5eb..d2c667465fd4 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -2424,6 +2424,10 @@ int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root)
 	btrfs_debug(fs_info, "cleaner removing %llu", root->root_key.objectid);
 
 	btrfs_kill_all_delayed_nodes(root);
+	if (root->ino_cache_inode) {
+		iput(root->ino_cache_inode);
+		root->ino_cache_inode = NULL;
+	}
 
 	if (btrfs_header_backref_rev(root->node) <
 			BTRFS_MIXED_BACKREF_REV)
-- 
2.26.2