[Ocfs2-devel] [PATCH 2/3] Ocfs2: Change ocfs2_prepare_refcount_change_for_del() a bit to defer blocks reservation.

[Tristan Ye]

As ocfs2_prepare_refcount_change_for_del() only called from ocfs2_commit_truncate for
now(punching holes are going to use that soon I guess), we're safe to defer metadata
blocks reservation unitl ocfs2_remove_btree_range(), who is also reserving blocks for
extent btree adjusting, so it will be nice to do these in one go.

Instead, it will return the blocks calculated to caller, to let him know how many extra
blocks for refcount tree should be reserved next.

Signed-off-by: Tristan Ye <tristan.ye at oracle.com>
---
 fs/ocfs2/refcounttree.c |   21 +++++++--------------
 fs/ocfs2/refcounttree.h |    2 +-
 2 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 60287fc..42a8446 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -2432,8 +2432,8 @@ out:
  *
  * Normally the refcount blocks store these refcount should be
  * continguous also, so that we can get the number easily.
- * As for meta_ac, we will at most add split 2 refcount record and
- * 2 more refcount block, so just check it in a rough way.
+ * We will at most add split 2 refcount records and 2 more
+ * refcount block, so just check it in a rough way.
  *
  * Caller must hold refcount tree lock.
  */
@@ -2442,9 +2442,9 @@ int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
 					  u64 phys_blkno,
 					  u32 clusters,
 					  int *credits,
-					  struct ocfs2_alloc_context **meta_ac)
+					  int *ref_blocks)
 {
-	int ret, ref_blocks = 0;
+	int ret;
 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
 	struct buffer_head *ref_root_bh = NULL;
@@ -2480,21 +2480,14 @@ int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
 					       &tree->rf_ci,
 					       ref_root_bh,
 					       start_cpos, clusters,
-					       &ref_blocks, credits);
+					       ref_blocks, credits);
 	if (ret) {
 		mlog_errno(ret);
 		goto out;
 	}
 
-	mlog(0, "reserve new metadata %d, credits = %d\n",
-	     ref_blocks, *credits);
-
-	if (ref_blocks) {
-		ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(inode->i_sb),
-							ref_blocks, meta_ac);
-		if (ret)
-			mlog_errno(ret);
-	}
+	mlog(0, "reserve new metadata %d blocks, credits = %d\n",
+	     *ref_blocks, *credits);
 
 out:
 	brelse(ref_root_bh);
diff --git a/fs/ocfs2/refcounttree.h b/fs/ocfs2/refcounttree.h
index c1d19b1..f4bf110 100644
--- a/fs/ocfs2/refcounttree.h
+++ b/fs/ocfs2/refcounttree.h
@@ -51,7 +51,7 @@ int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
 					  u64 phys_blkno,
 					  u32 clusters,
 					  int *credits,
-					  struct ocfs2_alloc_context **meta_ac);
+					  int *ref_blocks);
 int ocfs2_refcount_cow(struct inode *inode, struct buffer_head *di_bh,
 		       u32 cpos, u32 write_len, u32 max_cpos);
 
-- 
1.5.5