ext4: replace cut'n'pasted llseek code with generic_file_llseek_size

This gives ext4 the benefits of unlocked llseek.

Cc: tytso@mit.edu
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 1 insertions, 46 deletions

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index e4095e988eba..b9548f477bb8 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -224,53 +224,8 @@ loff_t ext4_llseek(struct file *file, loff_t offset, int origin)
                 maxbytes = EXT4_SB(inode->i_sb)->s_bitmap_maxbytes;
         else
                 maxbytes = inode->i_sb->s_maxbytes;
-        mutex_lock(&inode->i_mutex);
-        switch (origin) {
-        case SEEK_END:
-                offset += inode->i_size;
-                break;
-        case SEEK_CUR:
-                if (offset == 0) {
-                        mutex_unlock(&inode->i_mutex);
-                        return file->f_pos;
-                }
-                offset += file->f_pos;
-                break;
-        case SEEK_DATA:
-                /*
-                 * In the generic case the entire file is data, so as long as
-                 * offset isn't at the end of the file then the offset is data.
-                 */
-                if (offset >= inode->i_size) {
-                        mutex_unlock(&inode->i_mutex);
-                        return -ENXIO;
-                }
-                break;
-        case SEEK_HOLE:
-                /*
-                 * There is a virtual hole at the end of the file, so as long as
-                 * offset isn't i_size or larger, return i_size.
-                 */
-                if (offset >= inode->i_size) {
-                        mutex_unlock(&inode->i_mutex);
-                        return -ENXIO;
-                }
-                offset = inode->i_size;
-                break;
-        }
-
-        if (offset < 0 || offset > maxbytes) {
-                mutex_unlock(&inode->i_mutex);
-                return -EINVAL;
-        }
-
-        if (offset != file->f_pos) {
-                file->f_pos = offset;
-                file->f_version = 0;
-        }
-        mutex_unlock(&inode->i_mutex);
 
-        return offset;
+        return generic_file_llseek_size(file, offset, origin, maxbytes);
 }
 
 const struct file_operations ext4_file_operations = {