ext4: only zero partial blocks in ext4_zero_partial_blocks()

[platform/adaptation/renesas_rcar/renesas_kernel.git] / fs / ext4 / inode.c

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 0994234..502a9e1 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3424,33 +3424,36 @@ int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
 {
        struct super_block *sb = inode->i_sb;
        struct address_space *mapping = inode->i_mapping;
-       unsigned partial = lstart & (sb->s_blocksize - 1);
+       unsigned partial_start, partial_end;
        ext4_fsblk_t start, end;
        loff_t byte_end = (lstart + length - 1);
        int err = 0;
 
+       partial_start = lstart & (sb->s_blocksize - 1);
+       partial_end = byte_end & (sb->s_blocksize - 1);
+
        start = lstart >> sb->s_blocksize_bits;
        end = byte_end >> sb->s_blocksize_bits;
 
        /* Handle partial zero within the single block */
-       if (start == end) {
+       if (start == end &&
+           (partial_start || (partial_end != sb->s_blocksize - 1))) {
                err = ext4_block_zero_page_range(handle, mapping,
                                                 lstart, length);
                return err;
        }
        /* Handle partial zero out on the start of the range */
-       if (partial) {
+       if (partial_start) {
                err = ext4_block_zero_page_range(handle, mapping,
                                                 lstart, sb->s_blocksize);
                if (err)
                        return err;
        }
        /* Handle partial zero out on the end of the range */
-       partial = byte_end & (sb->s_blocksize - 1);
-       if (partial != sb->s_blocksize - 1)
+       if (partial_end != sb->s_blocksize - 1)
                err = ext4_block_zero_page_range(handle, mapping,
-                                                byte_end - partial,
-                                                partial + 1);
+                                                byte_end - partial_end,
+                                                partial_end + 1);
        return err;
 }