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>

1 files changed, 22 insertions, 34 deletions

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 20f1c03b6077..3736d9dfe325 100644
--- 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;
 }