ext4: remove unreachable code in 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 immediately return.

But right after that test, we test again for an uninit
extent; we can never hit this.  So just remove the impossible
test and associated variable.

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>

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 54d52afcdb198d6b55d28a479cfa9e353ab96100..de6d4674ba6ead8846903e752fa1ea6855204c42 100644 (file)
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -1666,7 +1666,7 @@ int
 ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
                                struct ext4_extent *ex2)
 {
-       unsigned short ext1_ee_len, ext2_ee_len, max_len;
+       unsigned short ext1_ee_len, ext2_ee_len;
 
        /*
         * Make sure that both extents are initialized. We don't merge
@@ -1677,11 +1677,6 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
        if (ext4_ext_is_uninitialized(ex1) || ext4_ext_is_uninitialized(ex2))
                return 0;
 
-       if (ext4_ext_is_uninitialized(ex1))
-               max_len = EXT_UNINIT_MAX_LEN;
-       else
-               max_len = EXT_INIT_MAX_LEN;
-
        ext1_ee_len = ext4_ext_get_actual_len(ex1);
        ext2_ee_len = ext4_ext_get_actual_len(ex2);
 
@@ -1694,7 +1689,7 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
         * as an RO_COMPAT feature, refuse to merge to extents if
         * this can result in the top bit of ee_len being set.
         */
-       if (ext1_ee_len + ext2_ee_len > max_len)
+       if (ext1_ee_len + ext2_ee_len > EXT_INIT_MAX_LEN)
                return 0;
 #ifdef AGGRESSIVE_TEST
        if (ext1_ee_len >= 4)