[6/9] btrfs: qgroup: Return actually freed bytes for qgroup release or free data

Commit Message

Qu Wenruo Feb. 27, 2017, 7:10 a.m. UTC

btrfs_qgroup_release/free_data() only returns 0 or minus error
number(ENOMEM is the only possible error).

This is normally good enough, but sometimes we need the accurate byte
number it freed/released.

Change it to return actually released/freed bytenr number instead of 0
for success.
And slightly modify related extent_changeset structure, since in btrfs
one none-hole data extent won't be larger than 128M, so "unsigned int"
is large enough for the use case.

Signed-off-by: Qu Wenruo <[e-mail]>
---
 fs/btrfs/extent-tree.c | 2 +-
 fs/btrfs/extent_io.h   | 2 +-
 fs/btrfs/qgroup.c      | 1 +
 3 files changed, 3 insertions(+), 2 deletions(-)

Patch

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c35b96633554..16b0d82dcd03 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4287,7 +4287,7 @@  int btrfs_check_data_free_space(struct inode *inode, u64 start, u64 len)
 
 	/* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
 	ret = btrfs_qgroup_reserve_data(inode, start, len);
-	if (ret)
+	if (ret < 0)
 		btrfs_free_reserved_data_space_noquota(inode, start, len);
 	return ret;
 }
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 270d03be290e..b6c3c2a588d4 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -190,7 +190,7 @@  struct extent_buffer {
  */
 struct extent_changeset {
 	/* How many bytes are set/cleared in this operation */
-	u64 bytes_changed;
+	unsigned int bytes_changed;
 
 	/* Changed ranges */
 	struct ulist range_changed;
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 4aabeb77d83c..4b0f4d2bd63c 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -2923,6 +2923,7 @@  static int __btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len,
 		btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
 				BTRFS_I(inode)->root->objectid,
 				changeset.bytes_changed);
+	ret = changeset.bytes_changed;
 out:
 	ulist_release(&changeset.range_changed);
 	return ret;