ext4: factor out common code in ext4_file_write()

This shouldn't change any logic flow; just delete duplicated code.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 20f1c03b6077e4ac39987a51dce0b95bcf7a8d2f..3736d9dfe3258a2303e310ae837290627e8b887b 100644 (file)
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -97,8 +97,9 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
 {
        struct file *file = iocb->ki_filp;
        struct inode *inode = file_inode(iocb->ki_filp);
+       struct mutex *aio_mutex = NULL;
        struct blk_plug plug;
-       int unaligned_aio = 0;
+       int o_direct = file->f_flags & O_DIRECT;
        int overwrite = 0;
        size_t length = iov_length(iov, nr_segs);
        ssize_t ret;
@@ -123,15 +124,13 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
                }
        }
 
-       if (unlikely(iocb->ki_filp->f_flags & O_DIRECT)) {
-               if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
-                   !is_sync_kiocb(iocb))
-                       unaligned_aio = ext4_unaligned_aio(inode, iov,
-                                                          nr_segs, pos);
-
+       if (o_direct) {
                /* Unaligned direct AIO must be serialized; see comment above */
-               if (unaligned_aio) {
-                       mutex_lock(ext4_aio_mutex(inode));
+               if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
+                   !is_sync_kiocb(iocb) &&
+                   ext4_unaligned_aio(inode, iov, nr_segs, pos)) {
+                       aio_mutex = ext4_aio_mutex(inode);
+                       mutex_lock(aio_mutex);
                        ext4_unwritten_wait(inode);
                }
 
@@ -141,7 +140,7 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
                iocb->private = &overwrite;
 
                /* check whether we do a DIO overwrite or not */
-               if (ext4_should_dioread_nolock(inode) && !unaligned_aio &&
+               if (ext4_should_dioread_nolock(inode) && !aio_mutex &&
                    !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
                        struct ext4_map_blocks map;
                        unsigned int blkbits = inode->i_blkbits;
@@ -168,35 +167,24 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
                        if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
                                overwrite = 1;
                }
-
-               ret = __generic_file_aio_write(iocb, iov, nr_segs);
-               mutex_unlock(&inode->i_mutex);
-
-               if (ret > 0) {
-                       ssize_t err;
-
-                       err = generic_write_sync(file, iocb->ki_pos - ret, ret);
-                       if (err < 0)
-                               ret = err;
-               }
-               blk_finish_plug(&plug);
-
-               if (unaligned_aio)
-                       mutex_unlock(ext4_aio_mutex(inode));
-       } else {
+       } else
                mutex_lock(&inode->i_mutex);
-               ret = __generic_file_aio_write(iocb, iov, nr_segs);
-               mutex_unlock(&inode->i_mutex);
 
-               if (ret > 0) {
-                       ssize_t err;
+       ret = __generic_file_aio_write(iocb, iov, nr_segs);
+       mutex_unlock(&inode->i_mutex);
 
-                       err = generic_write_sync(file, iocb->ki_pos - ret, ret);
-                       if (err < 0)
-                               ret = err;
-               }
+       if (ret > 0) {
+               ssize_t err;
+
+               err = generic_write_sync(file, iocb->ki_pos - ret, ret);
+               if (err < 0)
+                       ret = err;
        }
+       if (o_direct)
+               blk_finish_plug(&plug);
 
+       if (aio_mutex)
+               mutex_unlock(aio_mutex);
        return ret;
 }