1 files changed, 18 insertions, 16 deletions

diff --git a/fs/direct-io.c b/fs/direct-io.c
index 472037732daf..3bf3f20f8ecc 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -224,9 +224,9 @@ static inline struct page *dio_get_page(struct dio *dio,
  * filesystems can use it to hold additional state between get_block calls and
  * dio_complete.
  */
-static ssize_t dio_complete(struct dio *dio, loff_t offset, ssize_t ret,
-                bool is_async)
+static ssize_t dio_complete(struct dio *dio, ssize_t ret, bool is_async)
 {
+        loff_t offset = dio->iocb->ki_pos;
         ssize_t transferred = 0;
 
         /*
@@ -256,6 +256,7 @@ static ssize_t dio_complete(struct dio *dio, loff_t offset, ssize_t ret,
         if (dio->end_io) {
                 int err;
 
+                // XXX: ki_pos??
                 err = dio->end_io(dio->iocb, offset, ret, dio->private);
                 if (err)
                         ret = err;
@@ -265,15 +266,15 @@ static ssize_t dio_complete(struct dio *dio, loff_t offset, ssize_t ret,
                 inode_dio_end(dio->inode);
 
         if (is_async) {
-                if (dio->rw & WRITE) {
-                        int err;
-
-                        err = generic_write_sync(dio->iocb->ki_filp, offset,
-                                                 transferred);
-                        if (err < 0 && ret > 0)
-                                ret = err;
-                }
+                /*
+                 * generic_write_sync expects ki_pos to have been updated
+                 * already, but the submission path only does this for
+                 * synchronous I/O.
+                 */
+                dio->iocb->ki_pos += transferred;
 
+                if (dio->rw & WRITE)
+                        ret = generic_write_sync(dio->iocb,  transferred);
                 dio->iocb->ki_complete(dio->iocb, ret, 0);
         }
 
@@ -285,7 +286,7 @@ static void dio_aio_complete_work(struct work_struct *work)
 {
         struct dio *dio = container_of(work, struct dio, complete_work);
 
-        dio_complete(dio, dio->iocb->ki_pos, 0, true);
+        dio_complete(dio, 0, true);
 }
 
 static int dio_bio_complete(struct dio *dio, struct bio *bio);
@@ -314,7 +315,7 @@ static void dio_bio_end_aio(struct bio *bio)
                         queue_work(dio->inode->i_sb->s_dio_done_wq,
                                    &dio->complete_work);
                 } else {
-                        dio_complete(dio, dio->iocb->ki_pos, 0, true);
+                        dio_complete(dio, 0, true);
                 }
         }
 }
@@ -1113,7 +1114,7 @@ static inline int drop_refcount(struct dio *dio)
 static inline ssize_t
 do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
                       struct block_device *bdev, struct iov_iter *iter,
-                      loff_t offset, get_block_t get_block, dio_iodone_t end_io,
+                      get_block_t get_block, dio_iodone_t end_io,
                       dio_submit_t submit_io, int flags)
 {
         unsigned i_blkbits = ACCESS_ONCE(inode->i_blkbits);
@@ -1121,6 +1122,7 @@ do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
         unsigned blocksize_mask = (1 << blkbits) - 1;
         ssize_t retval = -EINVAL;
         size_t count = iov_iter_count(iter);
+        loff_t offset = iocb->ki_pos;
         loff_t end = offset + count;
         struct dio *dio;
         struct dio_submit sdio = { 0, };
@@ -1318,7 +1320,7 @@ do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
                 dio_await_completion(dio);
 
         if (drop_refcount(dio) == 0) {
-                retval = dio_complete(dio, offset, retval, false);
+                retval = dio_complete(dio, retval, false);
         } else
                 BUG_ON(retval != -EIOCBQUEUED);
 
@@ -1328,7 +1330,7 @@ out:
 
 ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
                              struct block_device *bdev, struct iov_iter *iter,
-                             loff_t offset, get_block_t get_block,
+                             get_block_t get_block,
                              dio_iodone_t end_io, dio_submit_t submit_io,
                              int flags)
 {
@@ -1344,7 +1346,7 @@ ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
         prefetch(bdev->bd_queue);
         prefetch((char *)bdev->bd_queue + SMP_CACHE_BYTES);
 
-        return do_blockdev_direct_IO(iocb, inode, bdev, iter, offset, get_block,
+        return do_blockdev_direct_IO(iocb, inode, bdev, iter, get_block,
                                      end_io, submit_io, flags);
 }