[PATCH 1/4] btrfs: declare free_ipath() via DEFINE_FREE() instead

["Miquel Sabaté Solà" <mssola@mssola.com>]

This transforms the signature to __free_ipath() instead of the original
free_ipath(), but this function was only being used as a cleanup
function anyways. Hence, define it as a helper and use it via the
__free() attribute on all uses. This change also means that
__free_ipath() will be inlined whereas that wasn't the case for the
original one, but this shouldn't be a problem.

A follow up macro like we do with BTRFS_PATH_AUTO_FREE() has been
discarded as the usage of this struct is not as widespread as that.

Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>
---
 fs/btrfs/backref.c | 10 +---------
 fs/btrfs/backref.h |  7 ++++++-
 fs/btrfs/inode.c   |  4 +---
 fs/btrfs/ioctl.c   |  3 +--
 fs/btrfs/scrub.c   |  4 +---
 5 files changed, 10 insertions(+), 18 deletions(-)

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index e050d0938dc4..a1456402752a 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -2785,7 +2785,7 @@ struct btrfs_data_container *init_data_container(u32 total_bytes)
  * allocates space to return multiple file system paths for an inode.
  * total_bytes to allocate are passed, note that space usable for actual path
  * information will be total_bytes - sizeof(struct inode_fs_paths).
- * the returned pointer must be freed with free_ipath() in the end.
+ * the returned pointer must be freed with __free_ipath() in the end.
  */
 struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root,
 					struct btrfs_path *path)
@@ -2810,14 +2810,6 @@ struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root,
 	return ifp;
 }
 
-void free_ipath(struct inode_fs_paths *ipath)
-{
-	if (!ipath)
-		return;
-	kvfree(ipath->fspath);
-	kfree(ipath);
-}
-
 struct btrfs_backref_iter *btrfs_backref_iter_alloc(struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_backref_iter *ret;
diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h
index 25d51c246070..d3b1ad281793 100644
--- a/fs/btrfs/backref.h
+++ b/fs/btrfs/backref.h
@@ -241,7 +241,12 @@ char *btrfs_ref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
 struct btrfs_data_container *init_data_container(u32 total_bytes);
 struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root,
 					struct btrfs_path *path);
-void free_ipath(struct inode_fs_paths *ipath);
+
+DEFINE_FREE(ipath, struct inode_fs_paths *,
+	if (_T) {
+		kvfree(_T->fspath);
+		kfree(_T);
+	})
 
 int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
 			  u64 start_off, struct btrfs_path *path,
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 79732756b87f..4d154209d70b 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -130,7 +130,7 @@ static int data_reloc_print_warning_inode(u64 inum, u64 offset, u64 num_bytes,
 	struct btrfs_fs_info *fs_info = warn->fs_info;
 	struct extent_buffer *eb;
 	struct btrfs_inode_item *inode_item;
-	struct inode_fs_paths *ipath = NULL;
+	struct inode_fs_paths *ipath __free(ipath) = NULL;
 	struct btrfs_root *local_root;
 	struct btrfs_key key;
 	unsigned int nofs_flag;
@@ -193,7 +193,6 @@ static int data_reloc_print_warning_inode(u64 inum, u64 offset, u64 num_bytes,
 	}
 
 	btrfs_put_root(local_root);
-	free_ipath(ipath);
 	return 0;
 
 err:
@@ -201,7 +200,6 @@ static int data_reloc_print_warning_inode(u64 inum, u64 offset, u64 num_bytes,
 "checksum error at logical %llu mirror %u root %llu inode %llu offset %llu, path resolving failed with ret=%d",
 		   warn->logical, warn->mirror_num, root, inum, offset, ret);
 
-	free_ipath(ipath);
 	return ret;
 }
 
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 692016b2b600..453832ded917 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3298,7 +3298,7 @@ static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
 	u64 rel_ptr;
 	int size;
 	struct btrfs_ioctl_ino_path_args *ipa = NULL;
-	struct inode_fs_paths *ipath = NULL;
+	struct inode_fs_paths *ipath __free(ipath) = NULL;
 	struct btrfs_path *path;
 
 	if (!capable(CAP_DAC_READ_SEARCH))
@@ -3346,7 +3346,6 @@ static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
 
 out:
 	btrfs_free_path(path);
-	free_ipath(ipath);
 	kfree(ipa);
 
 	return ret;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index fe266785804e..74d8af1ff02d 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -505,7 +505,7 @@ static int scrub_print_warning_inode(u64 inum, u64 offset, u64 num_bytes,
 	struct btrfs_inode_item *inode_item;
 	struct scrub_warning *swarn = warn_ctx;
 	struct btrfs_fs_info *fs_info = swarn->dev->fs_info;
-	struct inode_fs_paths *ipath = NULL;
+	struct inode_fs_paths *ipath __free(ipath) = NULL;
 	struct btrfs_root *local_root;
 	struct btrfs_key key;
 
@@ -569,7 +569,6 @@ static int scrub_print_warning_inode(u64 inum, u64 offset, u64 num_bytes,
 				  (char *)(unsigned long)ipath->fspath->val[i]);
 
 	btrfs_put_root(local_root);
-	free_ipath(ipath);
 	return 0;
 
 err:
@@ -580,7 +579,6 @@ static int scrub_print_warning_inode(u64 inum, u64 offset, u64 num_bytes,
 			  swarn->physical,
 			  root, inum, offset, ret);
 
-	free_ipath(ipath);
 	return 0;
 }
 
-- 
2.51.1