ext4: remove unreachable code after ext4_can_extents_be_merged()

Commit ec22ba8e ("ext4: disable merging of uninitialized extents")
ensured that if either extent under consideration is uninit, we
decline to merge, and ext4_can_extents_be_merged() returns false.

So there is no need for the caller to then test whether the
extent under consideration is unitialized; if it were, we
wouldn't have gotten that far.

The comments were also inaccurate; ext4_can_extents_be_merged()
no longer XORs the states, it fails if *either* is uninit.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>

1 files changed, 0 insertions, 26 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index de6d4674ba6e..35f65cf4f318 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -1715,7 +1715,6 @@ static int ext4_ext_try_to_merge_right(struct inode *inode,
         struct ext4_extent_header *eh;
         unsigned int depth, len;
         int merge_done = 0;
-        int uninitialized = 0;
 
         depth = ext_depth(inode);
         BUG_ON(path[depth].p_hdr == NULL);
@@ -1725,12 +1724,8 @@ static int ext4_ext_try_to_merge_right(struct inode *inode,
                 if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
                         break;
                 /* merge with next extent! */
-                if (ext4_ext_is_uninitialized(ex))
-                        uninitialized = 1;
                 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
                                 + ext4_ext_get_actual_len(ex + 1));
-                if (uninitialized)
-                        ext4_ext_mark_uninitialized(ex);
 
                 if (ex + 1 < EXT_LAST_EXTENT(eh)) {
                         len = (EXT_LAST_EXTENT(eh) - ex - 1)
@@ -1885,7 +1880,6 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
         struct ext4_ext_path *npath = NULL;
         int depth, len, err;
         ext4_lblk_t next;
-        unsigned uninitialized = 0;
         int mb_flags = 0;
 
         if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
@@ -1937,18 +1931,8 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
                         if (err)
                                 return err;
 
-                        /*
-                         * ext4_can_extents_be_merged should have checked
-                         * that either both extents are uninitialized, or
-                         * both aren't. Thus we need to check only one of
-                         * them here.
-                         */
-                        if (ext4_ext_is_uninitialized(ex))
-                                uninitialized = 1;
                         ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
                                         + ext4_ext_get_actual_len(newext));
-                        if (uninitialized)
-                                ext4_ext_mark_uninitialized(ex);
                         eh = path[depth].p_hdr;
                         nearex = ex;
                         goto merge;
@@ -1971,20 +1955,10 @@ prepend:
                         if (err)
                                 return err;
 
-                        /*
-                         * ext4_can_extents_be_merged should have checked
-                         * that either both extents are uninitialized, or
-                         * both aren't. Thus we need to check only one of
-                         * them here.
-                         */
-                        if (ext4_ext_is_uninitialized(ex))
-                                uninitialized = 1;
                         ex->ee_block = newext->ee_block;
                         ext4_ext_store_pblock(ex, ext4_ext_pblock(newext));
                         ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
                                         + ext4_ext_get_actual_len(newext));
-                        if (uninitialized)
-                                ext4_ext_mark_uninitialized(ex);
                         eh = path[depth].p_hdr;
                         nearex = ex;
                         goto merge;