ext4: optimize block allocation on grow indepth

It is reasonable to prepend newly created index to older one.

[ Dropped no longer used function parameter newext. -tytso ]

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 14 insertions, 6 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 8170b3254767..c3ed9af20d20 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -1263,16 +1263,24 @@ cleanup:
  *   just created block
  */
 static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
-                                 unsigned int flags,
-                                 struct ext4_extent *newext)
+                                 unsigned int flags)
 {
         struct ext4_extent_header *neh;
         struct buffer_head *bh;
-        ext4_fsblk_t newblock;
+        ext4_fsblk_t newblock, goal = 0;
+        struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
         int err = 0;
 
-        newblock = ext4_ext_new_meta_block(handle, inode, NULL,
-                newext, &err, flags);
+        /* Try to prepend new index to old one */
+        if (ext_depth(inode))
+                goal = ext4_idx_pblock(EXT_FIRST_INDEX(ext_inode_hdr(inode)));
+        if (goal > le32_to_cpu(es->s_first_data_block)) {
+                flags |= EXT4_MB_HINT_TRY_GOAL;
+                goal--;
+        } else
+                goal = ext4_inode_to_goal_block(inode);
+        newblock = ext4_new_meta_blocks(handle, inode, goal, flags,
+                                        NULL, &err);
         if (newblock == 0)
                 return err;
 
@@ -1373,7 +1381,7 @@ repeat:
                         err = PTR_ERR(path);
         } else {
                 /* tree is full, time to grow in depth */
-                err = ext4_ext_grow_indepth(handle, inode, mb_flags, newext);
+                err = ext4_ext_grow_indepth(handle, inode, mb_flags);
                 if (err)
                         goto out;