Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2: (32 commits)
  [PATCH] ocfs2: zero_user_page conversion
  ocfs2: Support xfs style space reservation ioctls
  ocfs2: support for removing file regions
  ocfs2: update truncate handling of partial clusters
  ocfs2: btree support for removal of arbirtrary extents
  ocfs2: Support creation of unwritten extents
  ocfs2: support writing of unwritten extents
  ocfs2: small cleanup of ocfs2_write_begin_nolock()
  ocfs2: btree changes for unwritten extents
  ocfs2: abstract btree growing calls
  ocfs2: use all extent block suballocators
  ocfs2: plug truncate into cached dealloc routines
  ocfs2: simplify deallocation locking
  ocfs2: harden buffer check during mapping of page blocks
  ocfs2: shared writeable mmap
  ocfs2: factor out write aops into nolock variants
  ocfs2: rework ocfs2_buffered_write_cluster()
  ocfs2: take ip_alloc_sem during entire truncate
  ocfs2: Add "preferred slot" mount option
  [KJ PATCH] Replacing memset(<addr>,0,PAGE_SIZE) with clear_page() in fs/ocfs2/dlm/dlmrecovery.c
  ...

31 files changed, 4231 insertions, 980 deletions

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 19712a7d145..f5e11f4fa95 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -50,6 +50,8 @@
 #include "buffer_head_io.h"
 
 static void ocfs2_free_truncate_context(struct ocfs2_truncate_context *tc);
+static int ocfs2_cache_extent_block_free(struct ocfs2_cached_dealloc_ctxt *ctxt,
+					 struct ocfs2_extent_block *eb);
 
 /*
  * Structures which describe a path through a btree, and functions to
@@ -117,6 +119,31 @@ static void ocfs2_free_path(struct ocfs2_path *path)
 }
 
 /*
+ * All the elements of src into dest. After this call, src could be freed
+ * without affecting dest.
+ *
+ * Both paths should have the same root. Any non-root elements of dest
+ * will be freed.
+ */
+static void ocfs2_cp_path(struct ocfs2_path *dest, struct ocfs2_path *src)
+{
+	int i;
+
+	BUG_ON(path_root_bh(dest) != path_root_bh(src));
+	BUG_ON(path_root_el(dest) != path_root_el(src));
+
+	ocfs2_reinit_path(dest, 1);
+
+	for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
+		dest->p_node[i].bh = src->p_node[i].bh;
+		dest->p_node[i].el = src->p_node[i].el;
+
+		if (dest->p_node[i].bh)
+			get_bh(dest->p_node[i].bh);
+	}
+}
+
+/*
  * Make the *dest path the same as src and re-initialize src path to
  * have a root only.
  */
@@ -212,10 +239,41 @@ out:
 	return ret;
 }
 
+/*
+ * Return the index of the extent record which contains cluster #v_cluster.
+ * -1 is returned if it was not found.
+ *
+ * Should work fine on interior and exterior nodes.
+ */
+int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster)
+{
+	int ret = -1;
+	int i;
+	struct ocfs2_extent_rec *rec;
+	u32 rec_end, rec_start, clusters;
+
+	for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
+		rec = &el->l_recs[i];
+
+		rec_start = le32_to_cpu(rec->e_cpos);
+		clusters = ocfs2_rec_clusters(el, rec);
+
+		rec_end = rec_start + clusters;
+
+		if (v_cluster >= rec_start && v_cluster < rec_end) {
+			ret = i;
+			break;
+		}
+	}
+
+	return ret;
+}
+
 enum ocfs2_contig_type {
 	CONTIG_NONE = 0,
 	CONTIG_LEFT,
-	CONTIG_RIGHT
+	CONTIG_RIGHT,
+	CONTIG_LEFTRIGHT,
 };
 
 
@@ -253,6 +311,14 @@ static enum ocfs2_contig_type
 {
 	u64 blkno = le64_to_cpu(insert_rec->e_blkno);
 
+	/*
+	 * Refuse to coalesce extent records with different flag
+	 * fields - we don't want to mix unwritten extents with user
+	 * data.
+	 */
+	if (ext->e_flags != insert_rec->e_flags)
+		return CONTIG_NONE;
+
 	if (ocfs2_extents_adjacent(ext, insert_rec) &&
 	    ocfs2_block_extent_contig(inode->i_sb, ext, blkno))
 			return CONTIG_RIGHT;
@@ -277,7 +343,14 @@ enum ocfs2_append_type {
 	APPEND_TAIL,
 };
 
+enum ocfs2_split_type {
+	SPLIT_NONE = 0,
+	SPLIT_LEFT,
+	SPLIT_RIGHT,
+};
+
 struct ocfs2_insert_type {
+	enum ocfs2_split_type	ins_split;
 	enum ocfs2_append_type	ins_appending;
 	enum ocfs2_contig_type	ins_contig;
 	int			ins_contig_index;
@@ -285,6 +358,13 @@ struct ocfs2_insert_type {
 	int			ins_tree_depth;
 };
 
+struct ocfs2_merge_ctxt {
+	enum ocfs2_contig_type	c_contig_type;
+	int			c_has_empty_extent;
+	int			c_split_covers_rec;
+	int			c_used_tail_recs;
+};
+
 /*
  * How many free extents have we got before we need more meta data?
  */
@@ -384,13 +464,7 @@ static int ocfs2_create_new_meta_bhs(struct ocfs2_super *osb,
 			strcpy(eb->h_signature, OCFS2_EXTENT_BLOCK_SIGNATURE);
 			eb->h_blkno = cpu_to_le64(first_blkno);
 			eb->h_fs_generation = cpu_to_le32(osb->fs_generation);
-
-#ifndef OCFS2_USE_ALL_METADATA_SUBALLOCATORS
-			/* we always use slot zero's suballocator */
-			eb->h_suballoc_slot = 0;
-#else
 			eb->h_suballoc_slot = cpu_to_le16(osb->slot_num);
-#endif
 			eb->h_suballoc_bit = cpu_to_le16(suballoc_bit_start);
 			eb->h_list.l_count =
 				cpu_to_le16(ocfs2_extent_recs_per_eb(osb->sb));
@@ -461,7 +535,7 @@ static int ocfs2_add_branch(struct ocfs2_super *osb,
 			    struct inode *inode,
 			    struct buffer_head *fe_bh,
 			    struct buffer_head *eb_bh,
-			    struct buffer_head *last_eb_bh,
+			    struct buffer_head **last_eb_bh,
 			    struct ocfs2_alloc_context *meta_ac)
 {
 	int status, new_blocks, i;
@@ -476,7 +550,7 @@ static int ocfs2_add_branch(struct ocfs2_super *osb,
 
 	mlog_entry_void();
 
-	BUG_ON(!last_eb_bh);
+	BUG_ON(!last_eb_bh || !*last_eb_bh);
 
 	fe = (struct ocfs2_dinode *) fe_bh->b_data;
 
@@ -507,7 +581,7 @@ static int ocfs2_add_branch(struct ocfs2_super *osb,
 		goto bail;
 	}
 
-	eb = (struct ocfs2_extent_block *)last_eb_bh->b_data;
+	eb = (struct ocfs2_extent_block *)(*last_eb_bh)->b_data;
 	new_cpos = ocfs2_sum_rightmost_rec(&eb->h_list);
 
 	/* Note: new_eb_bhs[new_blocks - 1] is the guy which will be
@@ -568,7 +642,7 @@ static int ocfs2_add_branch(struct ocfs2_super *osb,
 	 * journal_dirty erroring as it won't unless we've aborted the
 	 * handle (in which case we would never be here) so reserving
 	 * the write with journal_access is all we need to do. */
-	status = ocfs2_journal_access(handle, inode, last_eb_bh,
+	status = ocfs2_journal_access(handle, inode, *last_eb_bh,
 				      OCFS2_JOURNAL_ACCESS_WRITE);
 	if (status < 0) {
 		mlog_errno(status);
@@ -601,10 +675,10 @@ static int ocfs2_add_branch(struct ocfs2_super *osb,
 	 * next_leaf on the previously last-extent-block. */
 	fe->i_last_eb_blk = cpu_to_le64(new_last_eb_blk);
 
-	eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
+	eb = (struct ocfs2_extent_block *) (*last_eb_bh)->b_data;
 	eb->h_next_leaf_blk = cpu_to_le64(new_last_eb_blk);
 
-	status = ocfs2_journal_dirty(handle, last_eb_bh);
+	status = ocfs2_journal_dirty(handle, *last_eb_bh);
 	if (status < 0)
 		mlog_errno(status);
 	status = ocfs2_journal_dirty(handle, fe_bh);
@@ -616,6 +690,14 @@ static int ocfs2_add_branch(struct ocfs2_super *osb,
 			mlog_errno(status);
 	}
 
+	/*
+	 * Some callers want to track the rightmost leaf so pass it
+	 * back here.
+	 */
+	brelse(*last_eb_bh);
+	get_bh(new_eb_bhs[0]);
+	*last_eb_bh = new_eb_bhs[0];
+
 	status = 0;
 bail:
 	if (new_eb_bhs) {
@@ -829,6 +911,87 @@ bail:
 }
 
 /*
+ * Grow a b-tree so that it has more records.
+ *
+ * We might shift the tree depth in which case existing paths should
+ * be considered invalid.
+ *
+ * Tree depth after the grow is returned via *final_depth.
+ *
+ * *last_eb_bh will be updated by ocfs2_add_branch().
+ */
+static int ocfs2_grow_tree(struct inode *inode, handle_t *handle,
+			   struct buffer_head *di_bh, int *final_depth,
+			   struct buffer_head **last_eb_bh,
+			   struct ocfs2_alloc_context *meta_ac)
+{
+	int ret, shift;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	int depth = le16_to_cpu(di->id2.i_list.l_tree_depth);
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct buffer_head *bh = NULL;
+
+	BUG_ON(meta_ac == NULL);
+
+	shift = ocfs2_find_branch_target(osb, inode, di_bh, &bh);
+	if (shift < 0) {
+		ret = shift;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	/* We traveled all the way to the bottom of the allocation tree
+	 * and didn't find room for any more extents - we need to add
+	 * another tree level */
+	if (shift) {
+		BUG_ON(bh);
+		mlog(0, "need to shift tree depth (current = %d)\n", depth);
+
+		/* ocfs2_shift_tree_depth will return us a buffer with
+		 * the new extent block (so we can pass that to
+		 * ocfs2_add_branch). */
+		ret = ocfs2_shift_tree_depth(osb, handle, inode, di_bh,
+					     meta_ac, &bh);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
+		}
+		depth++;
+		if (depth == 1) {
+			/*
+			 * Special case: we have room now if we shifted from
+			 * tree_depth 0, so no more work needs to be done.
+			 *
+			 * We won't be calling add_branch, so pass
+			 * back *last_eb_bh as the new leaf. At depth
+			 * zero, it should always be null so there's
+			 * no reason to brelse.
+			 */
+			BUG_ON(*last_eb_bh);
+			get_bh(bh);
+			*last_eb_bh = bh;
+			goto out;
+		}
+	}
+
+	/* call ocfs2_add_branch to add the final part of the tree with
+	 * the new data. */
+	mlog(0, "add branch. bh = %p\n", bh);
+	ret = ocfs2_add_branch(osb, handle, inode, di_bh, bh, last_eb_bh,
+			       meta_ac);
+	if (ret < 0) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+out:
+	if (final_depth)
+		*final_depth = depth;
+	brelse(bh);
+	return ret;
+}
+
+/*
  * This is only valid for leaf nodes, which are the only ones that can
  * have empty extents anyway.
  */
@@ -934,6 +1097,22 @@ static void ocfs2_rotate_leaf(struct ocfs2_extent_list *el,
 
 }
 
+static void ocfs2_remove_empty_extent(struct ocfs2_extent_list *el)
+{
+	int size, num_recs = le16_to_cpu(el->l_next_free_rec);
+
+	BUG_ON(num_recs == 0);
+
+	if (ocfs2_is_empty_extent(&el->l_recs[0])) {
+		num_recs--;
+		size = num_recs * sizeof(struct ocfs2_extent_rec);
+		memmove(&el->l_recs[0], &el->l_recs[1], size);
+		memset(&el->l_recs[num_recs], 0,
+		       sizeof(struct ocfs2_extent_rec));
+		el->l_next_free_rec = cpu_to_le16(num_recs);
+	}
+}
+
 /*
  * Create an empty extent record .
  *
@@ -1211,6 +1390,10 @@ static void ocfs2_adjust_adjacent_records(struct ocfs2_extent_rec *left_rec,
 	 * immediately to their right.
 	 */
 	left_clusters = le32_to_cpu(right_child_el->l_recs[0].e_cpos);
+	if (ocfs2_is_empty_extent(&right_child_el->l_recs[0])) {
+		BUG_ON(le16_to_cpu(right_child_el->l_next_free_rec) <= 1);
+		left_clusters = le32_to_cpu(right_child_el->l_recs[1].e_cpos);
+	}
 	left_clusters -= le32_to_cpu(left_rec->e_cpos);
 	left_rec->e_int_clusters = cpu_to_le32(left_clusters);
 
@@ -1531,10 +1714,16 @@ out:
 	return ret;
 }
 
+/*
+ * Extend the transaction by enough credits to complete the rotation,
+ * and still leave at least the original number of credits allocated
+ * to this transaction.
+ */
 static int ocfs2_extend_rotate_transaction(handle_t *handle, int subtree_depth,
+					   int op_credits,
 					   struct ocfs2_path *path)
 {
-	int credits = (path->p_tree_depth - subtree_depth) * 2 + 1;
+	int credits = (path->p_tree_depth - subtree_depth) * 2 + 1 + op_credits;
 
 	if (handle->h_buffer_credits < credits)
 		return ocfs2_extend_trans(handle, credits);
@@ -1568,6 +1757,29 @@ static int ocfs2_rotate_requires_path_adjustment(struct ocfs2_path *left_path,
 	return 0;
 }
 
+static int ocfs2_leftmost_rec_contains(struct ocfs2_extent_list *el, u32 cpos)
+{
+	int next_free = le16_to_cpu(el->l_next_free_rec);
+	unsigned int range;
+	struct ocfs2_extent_rec *rec;
+
+	if (next_free == 0)
+		return 0;
+
+	rec = &el->l_recs[0];
+	if (ocfs2_is_empty_extent(rec)) {
+		/* Empty list. */
+		if (next_free == 1)
+			return 0;
+		rec = &el->l_recs[1];
+	}
+
+	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
+	if (cpos >= le32_to_cpu(rec->e_cpos) && cpos < range)
+		return 1;
+	return 0;
+}
+
 /*
  * Rotate all the records in a btree right one record, starting at insert_cpos.
  *
@@ -1586,11 +1798,12 @@ static int ocfs2_rotate_requires_path_adjustment(struct ocfs2_path *left_path,
  */
 static int ocfs2_rotate_tree_right(struct inode *inode,
 				   handle_t *handle,
+				   enum ocfs2_split_type split,
 				   u32 insert_cpos,
 				   struct ocfs2_path *right_path,
 				   struct ocfs2_path **ret_left_path)
 {
-	int ret, start;
+	int ret, start, orig_credits = handle->h_buffer_credits;
 	u32 cpos;
 	struct ocfs2_path *left_path = NULL;
 
@@ -1657,9 +1870,9 @@ static int ocfs2_rotate_tree_right(struct inode *inode,
 				(unsigned long long)
 				path_leaf_bh(left_path)->b_blocknr);
 
-		if (ocfs2_rotate_requires_path_adjustment(left_path,
+		if (split == SPLIT_NONE &&
+		    ocfs2_rotate_requires_path_adjustment(left_path,
 							  insert_cpos)) {
-			mlog(0, "Path adjustment required\n");
 
 			/*
 			 * We've rotated the tree as much as we
@@ -1687,7 +1900,7 @@ static int ocfs2_rotate_tree_right(struct inode *inode,
 		     right_path->p_tree_depth);
 
 		ret = ocfs2_extend_rotate_transaction(handle, start,
-						      right_path);
+						      orig_credits, right_path);
 		if (ret) {
 			mlog_errno(ret);
 			goto out;
@@ -1700,6 +1913,24 @@ static int ocfs2_rotate_tree_right(struct inode *inode,
 			goto out;
 		}
 
+		if (split != SPLIT_NONE &&
+		    ocfs2_leftmost_rec_contains(path_leaf_el(right_path),
+						insert_cpos)) {
+			/*
+			 * A rotate moves the rightmost left leaf
+			 * record over to the leftmost right leaf
+			 * slot. If we're doing an extent split
+			 * instead of a real insert, then we have to
+			 * check that the extent to be split wasn't
+			 * just moved over. If it was, then we can
+			 * exit here, passing left_path back -
+			 * ocfs2_split_extent() is smart enough to
+			 * search both leaves.
+			 */
+			*ret_left_path = left_path;
+			goto out_ret_path;
+		}
+
 		/*
 		 * There is no need to re-read the next right path
 		 * as we know that it'll be our current left
@@ -1722,6 +1953,1031 @@ out_ret_path:
 	return ret;
 }
 
+static void ocfs2_update_edge_lengths(struct inode *inode, handle_t *handle,
+				      struct ocfs2_path *path)
+{
+	int i, idx;
+	struct ocfs2_extent_rec *rec;
+	struct ocfs2_extent_list *el;
+	struct ocfs2_extent_block *eb;
+	u32 range;
+
+	/* Path should always be rightmost. */
+	eb = (struct ocfs2_extent_block *)path_leaf_bh(path)->b_data;
+	BUG_ON(eb->h_next_leaf_blk != 0ULL);
+
+	el = &eb->h_list;
+	BUG_ON(le16_to_cpu(el->l_next_free_rec) == 0);
+	idx = le16_to_cpu(el->l_next_free_rec) - 1;
+	rec = &el->l_recs[idx];
+	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
+
+	for (i = 0; i < path->p_tree_depth; i++) {
+		el = path->p_node[i].el;
+		idx = le16_to_cpu(el->l_next_free_rec) - 1;
+		rec = &el->l_recs[idx];
+
+		rec->e_int_clusters = cpu_to_le32(range);
+		le32_add_cpu(&rec->e_int_clusters, -le32_to_cpu(rec->e_cpos));
+
+		ocfs2_journal_dirty(handle, path->p_node[i].bh);
+	}
+}
+
+static void ocfs2_unlink_path(struct inode *inode, handle_t *handle,
+			      struct ocfs2_cached_dealloc_ctxt *dealloc,
+			      struct ocfs2_path *path, int unlink_start)
+{
+	int ret, i;
+	struct ocfs2_extent_block *eb;
+	struct ocfs2_extent_list *el;
+	struct buffer_head *bh;
+
+	for(i = unlink_start; i < path_num_items(path); i++) {
+		bh = path->p_node[i].bh;
+
+		eb = (struct ocfs2_extent_block *)bh->b_data;
+		/*
+		 * Not all nodes might have had their final count
+		 * decremented by the caller - handle this here.
+		 */
+		el = &eb->h_list;
+		if (le16_to_cpu(el->l_next_free_rec) > 1) {
+			mlog(ML_ERROR,
+			     "Inode %llu, attempted to remove extent block "
+			     "%llu with %u records\n",
+			     (unsigned long long)OCFS2_I(inode)->ip_blkno,
+			     (unsigned long long)le64_to_cpu(eb->h_blkno),
+			     le16_to_cpu(el->l_next_free_rec));
+
+			ocfs2_journal_dirty(handle, bh);
+			ocfs2_remove_from_cache(inode, bh);
+			continue;
+		}
+
+		el->l_next_free_rec = 0;
+		memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
+
+		ocfs2_journal_dirty(handle, bh);
+
+		ret = ocfs2_cache_extent_block_free(dealloc, eb);
+		if (ret)
+			mlog_errno(ret);
+
+		ocfs2_remove_from_cache(inode, bh);
+	}
+}
+
+static void ocfs2_unlink_subtree(struct inode *inode, handle_t *handle,
+				 struct ocfs2_path *left_path,
+				 struct ocfs2_path *right_path,
+				 int subtree_index,
+				 struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+	int i;
+	struct buffer_head *root_bh = left_path->p_node[subtree_index].bh;
+	struct ocfs2_extent_list *root_el = left_path->p_node[subtree_index].el;
+	struct ocfs2_extent_list *el;
+	struct ocfs2_extent_block *eb;
+
+	el = path_leaf_el(left_path);
+
+	eb = (struct ocfs2_extent_block *)right_path->p_node[subtree_index + 1].bh->b_data;
+
+	for(i = 1; i < le16_to_cpu(root_el->l_next_free_rec); i++)
+		if (root_el->l_recs[i].e_blkno == eb->h_blkno)
+			break;
+
+	BUG_ON(i >= le16_to_cpu(root_el->l_next_free_rec));
+
+	memset(&root_el->l_recs[i], 0, sizeof(struct ocfs2_extent_rec));
+	le16_add_cpu(&root_el->l_next_free_rec, -1);
+
+	eb = (struct ocfs2_extent_block *)path_leaf_bh(left_path)->b_data;
+	eb->h_next_leaf_blk = 0;
+
+	ocfs2_journal_dirty(handle, root_bh);
+	ocfs2_journal_dirty(handle, path_leaf_bh(left_path));
+
+	ocfs2_unlink_path(inode, handle, dealloc, right_path,
+			  subtree_index + 1);
+}
+
+static int ocfs2_rotate_subtree_left(struct inode *inode, handle_t *handle,
+				     struct ocfs2_path *left_path,
+				     struct ocfs2_path *right_path,
+				     int subtree_index,
+				     struct ocfs2_cached_dealloc_ctxt *dealloc,
+				     int *deleted)
+{
+	int ret, i, del_right_subtree = 0, right_has_empty = 0;
+	struct buffer_head *root_bh, *di_bh = path_root_bh(right_path);
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	struct ocfs2_extent_list *right_leaf_el, *left_leaf_el;
+	struct ocfs2_extent_block *eb;
+
+	*deleted = 0;
+
+	right_leaf_el = path_leaf_el(right_path);
+	left_leaf_el = path_leaf_el(left_path);
+	root_bh = left_path->p_node[subtree_index].bh;
+	BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
+
+	if (!ocfs2_is_empty_extent(&left_leaf_el->l_recs[0]))
+		return 0;
+
+	eb = (struct ocfs2_extent_block *)path_leaf_bh(right_path)->b_data;
+	if (ocfs2_is_empty_extent(&right_leaf_el->l_recs[0])) {
+		/*
+		 * It's legal for us to proceed if the right leaf is
+		 * the rightmost one and it has an empty extent. There
+		 * are two cases to handle - whether the leaf will be
+		 * empty after removal or not. If the leaf isn't empty
+		 * then just remove the empty extent up front. The
+		 * next block will handle empty leaves by flagging
+		 * them for unlink.
+		 *
+		 * Non rightmost leaves will throw -EAGAIN and the
+		 * caller can manually move the subtree and retry.
+		 */
+
+		if (eb->h_next_leaf_blk != 0ULL)
+			return -EAGAIN;
+
+		if (le16_to_cpu(right_leaf_el->l_next_free_rec) > 1) {
+			ret = ocfs2_journal_access(handle, inode,
+						   path_leaf_bh(right_path),
+						   OCFS2_JOURNAL_ACCESS_WRITE);
+			if (ret) {
+				mlog_errno(ret);
+				goto out;
+			}
+
+			ocfs2_remove_empty_extent(right_leaf_el);
+		} else
+			right_has_empty = 1;
+	}
+
+	if (eb->h_next_leaf_blk == 0ULL &&
+	    le16_to_cpu(right_leaf_el->l_next_free_rec) == 1) {
+		/*
+		 * We have to update i_last_eb_blk during the meta
+		 * data delete.
+		 */
+		ret = ocfs2_journal_access(handle, inode, di_bh,
+					   OCFS2_JOURNAL_ACCESS_WRITE);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		del_right_subtree = 1;
+	}
+
+	/*
+	 * Getting here with an empty extent in the right path implies
+	 * that it's the rightmost path and will be deleted.
+	 */
+	BUG_ON(right_has_empty && !del_right_subtree);
+
+	ret = ocfs2_journal_access(handle, inode, root_bh,
+				   OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	for(i = subtree_index + 1; i < path_num_items(right_path); i++) {
+		ret = ocfs2_journal_access(handle, inode,
+					   right_path->p_node[i].bh,
+					   OCFS2_JOURNAL_ACCESS_WRITE);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		ret = ocfs2_journal_access(handle, inode,
+					   left_path->p_node[i].bh,
+					   OCFS2_JOURNAL_ACCESS_WRITE);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+	}
+
+	if (!right_has_empty) {
+		/*
+		 * Only do this if we're moving a real
+		 * record. Otherwise, the action is delayed until
+		 * after removal of the right path in which case we
+		 * can do a simple shift to remove the empty extent.
+		 */
+		ocfs2_rotate_leaf(left_leaf_el, &right_leaf_el->l_recs[0]);
+		memset(&right_leaf_el->l_recs[0], 0,
+		       sizeof(struct ocfs2_extent_rec));
+	}
+	if (eb->h_next_leaf_blk == 0ULL) {
+		/*
+		 * Move recs over to get rid of empty extent, decrease
+		 * next_free. This is allowed to remove the last
+		 * extent in our leaf (setting l_next_free_rec to
+		 * zero) - the delete code below won't care.
+		 */
+		ocfs2_remove_empty_extent(right_leaf_el);
+	}
+
+	ret = ocfs2_journal_dirty(handle, path_leaf_bh(left_path));
+	if (ret)
+		mlog_errno(ret);
+	ret = ocfs2_journal_dirty(handle, path_leaf_bh(right_path));
+	if (ret)
+		mlog_errno(ret);
+
+	if (del_right_subtree) {
+		ocfs2_unlink_subtree(inode, handle, left_path, right_path,
+				     subtree_index, dealloc);
+		ocfs2_update_edge_lengths(inode, handle, left_path);
+
+		eb = (struct ocfs2_extent_block *)path_leaf_bh(left_path)->b_data;
+		di->i_last_eb_blk = eb->h_blkno;
+
+		/*
+		 * Removal of the extent in the left leaf was skipped
+		 * above so we could delete the right path
+		 * 1st.
+		 */
+		if (right_has_empty)
+			ocfs2_remove_empty_extent(left_leaf_el);
+
+		ret = ocfs2_journal_dirty(handle, di_bh);
+		if (ret)
+			mlog_errno(ret);
+
+		*deleted = 1;
+	} else
+		ocfs2_complete_edge_insert(inode, handle, left_path, right_path,
+					   subtree_index);
+
+out:
+	return ret;
+}
+
+/*
+ * Given a full path, determine what cpos value would return us a path
+ * containing the leaf immediately to the right of the current one.
+ *
+ * Will return zero if the path passed in is already the rightmost path.
+ *
+ * This looks similar, but is subtly different to
+ * ocfs2_find_cpos_for_left_leaf().
+ */
+static int ocfs2_find_cpos_for_right_leaf(struct super_block *sb,
+					  struct ocfs2_path *path, u32 *cpos)
+{
+	int i, j, ret = 0;
+	u64 blkno;
+	struct ocfs2_extent_list *el;
+
+	*cpos = 0;
+
+	if (path->p_tree_depth == 0)
+		return 0;
+
+	blkno = path_leaf_bh(path)->b_blocknr;
+
+	/* Start at the tree node just above the leaf and work our way up. */
+	i = path->p_tree_depth - 1;
+	while (i >= 0) {
+		int next_free;
+
+		el = path->p_node[i].el;
+
+		/*
+		 * Find the extent record just after the one in our
+		 * path.
+		 */
+		next_free = le16_to_cpu(el->l_next_free_rec);
+		for(j = 0; j < le16_to_cpu(el->l_next_free_rec); j++) {
+			if (le64_to_cpu(el->l_recs[j].e_blkno) == blkno) {
+				if (j == (next_free - 1)) {
+					if (i == 0) {
+						/*
+						 * We've determined that the
+						 * path specified is already
+						 * the rightmost one - return a
+						 * cpos of zero.
+						 */
+						goto out;
+					}
+					/*
+					 * The rightmost record points to our
+					 * leaf - we need to travel up the
+					 * tree one level.
+					 */
+					goto next_node;
+				}
+
+				*cpos = le32_to_cpu(el->l_recs[j + 1].e_cpos);
+				goto out;
+			}
+		}
+
+		/*
+		 * If we got here, we never found a valid node where
+		 * the tree indicated one should be.
+		 */
+		ocfs2_error(sb,
+			    "Invalid extent tree at extent block %llu\n",
+			    (unsigned long long)blkno);
+		ret = -EROFS;
+		goto out;
+
+next_node:
+		blkno = path->p_node[i].bh->b_blocknr;
+		i--;
+	}
+
+out:
+	return ret;
+}
+
+static int ocfs2_rotate_rightmost_leaf_left(struct inode *inode,
+					    handle_t *handle,
+					    struct buffer_head *bh,
+					    struct ocfs2_extent_list *el)
+{
+	int ret;
+
+	if (!ocfs2_is_empty_extent(&el->l_recs[0]))
+		return 0;
+
+	ret = ocfs2_journal_access(handle, inode, bh,
+				   OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ocfs2_remove_empty_extent(el);
+
+	ret = ocfs2_journal_dirty(handle, bh);
+	if (ret)
+		mlog_errno(ret);
+
+out:
+	return ret;
+}
+
+static int __ocfs2_rotate_tree_left(struct inode *inode,
+				    handle_t *handle, int orig_credits,
+				    struct ocfs2_path *path,
+				    struct ocfs2_cached_dealloc_ctxt *dealloc,
+				    struct ocfs2_path **empty_extent_path)
+{
+	int ret, subtree_root, deleted;
+	u32 right_cpos;
+	struct ocfs2_path *left_path = NULL;
+	struct ocfs2_path *right_path = NULL;
+
+	BUG_ON(!ocfs2_is_empty_extent(&(path_leaf_el(path)->l_recs[0])));
+
+	*empty_extent_path = NULL;
+
+	ret = ocfs2_find_cpos_for_right_leaf(inode->i_sb, path,
+					     &right_cpos);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	left_path = ocfs2_new_path(path_root_bh(path),
+				   path_root_el(path));
+	if (!left_path) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ocfs2_cp_path(left_path, path);
+
+	right_path = ocfs2_new_path(path_root_bh(path),
+				    path_root_el(path));
+	if (!right_path) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	while (right_cpos) {
+		ret = ocfs2_find_path(inode, right_path, right_cpos);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		subtree_root = ocfs2_find_subtree_root(inode, left_path,
+						       right_path);
+
+		mlog(0, "Subtree root at index %d (blk %llu, depth %d)\n",
+		     subtree_root,
+		     (unsigned long long)
+		     right_path->p_node[subtree_root].bh->b_blocknr,
+		     right_path->p_tree_depth);
+
+		ret = ocfs2_extend_rotate_transaction(handle, subtree_root,
+						      orig_credits, left_path);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		ret = ocfs2_rotate_subtree_left(inode, handle, left_path,
+						right_path, subtree_root,
+						dealloc, &deleted);
+		if (ret == -EAGAIN) {
+			/*
+			 * The rotation has to temporarily stop due to
+			 * the right subtree having an empty
+			 * extent. Pass it back to the caller for a
+			 * fixup.
+			 */
+			*empty_extent_path = right_path;
+			right_path = NULL;
+			goto out;
+		}
+		if (ret