ocfs2: Modify ocfs2_num_free_extents for future xattr usage.

ocfs2_num_free_extents() is used to find the number of free extent records
in an inode btree. Hence, it takes an "ocfs2_dinode" parameter. We want to
use this for extended attribute trees in the future, so genericize the
interface the take a buffer head. A future patch will allow that buffer_head
to contain any structure rooting an ocfs2 btree.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

fs/ocfs2/alloc.c

@@ -368,12 +368,13 @@ struct ocfs2_merge_ctxt {
  */
 int ocfs2_num_free_extents(struct ocfs2_super *osb,
 			   struct inode *inode,
-			   struct ocfs2_dinode *fe)
+			   struct buffer_head *bh)
 {
 	int retval;
 	struct ocfs2_extent_list *el;
 	struct ocfs2_extent_block *eb;
 	struct buffer_head *eb_bh = NULL;
+	struct ocfs2_dinode *fe = (struct ocfs2_dinode *)bh->b_data;
 
 	mlog_entry_void();
 

fs/ocfs2/alloc.h

@@ -47,7 +47,7 @@ int ocfs2_remove_extent(struct inode *inode, struct buffer_head *di_bh,
 			struct ocfs2_cached_dealloc_ctxt *dealloc);
 int ocfs2_num_free_extents(struct ocfs2_super *osb,
 			   struct inode *inode,
-			   struct ocfs2_dinode *fe);
+			   struct buffer_head *bh);
 /* how many new metadata chunks would an allocation need at maximum? */
 static inline int ocfs2_extend_meta_needed(struct ocfs2_dinode *fe)
 {

fs/ocfs2/aops.c

@@ -1712,8 +1712,9 @@ int ocfs2_write_begin_nolock(struct address_space *mapping,
 		 * ocfs2_lock_allocators(). It greatly over-estimates
 		 * the work to be done.
 		 */
-		ret = ocfs2_lock_allocators(inode, di, clusters_to_alloc,
-					    extents_to_split, &data_ac, &meta_ac);
+		ret = ocfs2_lock_allocators(inode, wc->w_di_bh,
+					    clusters_to_alloc, extents_to_split,
+					    &data_ac, &meta_ac);
 		if (ret) {
 			mlog_errno(ret);
 			goto out;

fs/ocfs2/dir.c

@@ -1479,7 +1479,8 @@ static int ocfs2_extend_dir(struct ocfs2_super *osb,
 	spin_lock(&OCFS2_I(dir)->ip_lock);
 	if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) {
 		spin_unlock(&OCFS2_I(dir)->ip_lock);
-		num_free_extents = ocfs2_num_free_extents(osb, dir, fe);
+		num_free_extents = ocfs2_num_free_extents(osb, dir,
+							  parent_fe_bh);
 		if (num_free_extents < 0) {
 			status = num_free_extents;
 			mlog_errno(status);

fs/ocfs2/file.c

@@ -521,7 +521,7 @@ int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
 	if (mark_unwritten)
 		flags = OCFS2_EXT_UNWRITTEN;
 
-	free_extents = ocfs2_num_free_extents(osb, inode, fe);
+	free_extents = ocfs2_num_free_extents(osb, inode, fe_bh);
 	if (free_extents < 0) {
 		status = free_extents;
 		mlog_errno(status);
@@ -609,14 +609,15 @@ int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
  * File systems which don't support holes call this from
  * ocfs2_extend_allocation().
  */
-int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di,
+int ocfs2_lock_allocators(struct inode *inode, struct buffer_head *di_bh,
 			  u32 clusters_to_add, u32 extents_to_split,
 			  struct ocfs2_alloc_context **data_ac,
 			  struct ocfs2_alloc_context **meta_ac)
 {
 	int ret = 0, num_free_extents;
 	unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 
 	*meta_ac = NULL;
 	if (data_ac)
@@ -629,7 +630,7 @@ int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di,
 	     (unsigned long long)OCFS2_I(inode)->ip_blkno, (long long)i_size_read(inode),
 	     le32_to_cpu(di->i_clusters), clusters_to_add, extents_to_split);
 
-	num_free_extents = ocfs2_num_free_extents(osb, inode, di);
+	num_free_extents = ocfs2_num_free_extents(osb, inode, di_bh);
 	if (num_free_extents < 0) {
 		ret = num_free_extents;
 		mlog_errno(ret);
@@ -724,7 +725,7 @@ static int __ocfs2_extend_allocation(struct inode *inode, u32 logical_start,
 restart_all:
 	BUG_ON(le32_to_cpu(fe->i_clusters) != OCFS2_I(inode)->ip_clusters);
 
-	status = ocfs2_lock_allocators(inode, fe, clusters_to_add, 0, &data_ac,
+	status = ocfs2_lock_allocators(inode, bh, clusters_to_add, 0, &data_ac,
 				       &meta_ac);
 	if (status) {
 		mlog_errno(status);
@@ -1395,7 +1396,7 @@ static int __ocfs2_remove_inode_range(struct inode *inode,
 	struct ocfs2_alloc_context *meta_ac = NULL;
 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 
-	ret = ocfs2_lock_allocators(inode, di, 0, 1, NULL, &meta_ac);
+	ret = ocfs2_lock_allocators(inode, di_bh, 0, 1, NULL, &meta_ac);
 	if (ret) {
 		mlog_errno(ret);
 		return ret;

fs/ocfs2/file.h

@@ -57,7 +57,7 @@ int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
 			       enum ocfs2_alloc_restarted *reason_ret);
 int ocfs2_extend_no_holes(struct inode *inode, u64 new_i_size,
 			  u64 zero_to);
-int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di,
+int ocfs2_lock_allocators(struct inode *inode, struct buffer_head *fe,
 			  u32 clusters_to_add, u32 extents_to_split,
 			  struct ocfs2_alloc_context **data_ac,
 			  struct ocfs2_alloc_context **meta_ac);