ocfs2: fix ip_unaligned_aio deadlock with dio work queue

[uclinux-h8/linux.git] / fs / ocfs2 / file.c

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 1ab1823..c18ab45 100644 (file)
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2178,7 +2178,7 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
        int full_coherency = !(osb->s_mount_opt &
                               OCFS2_MOUNT_COHERENCY_BUFFERED);
-       int unaligned_dio = 0;
+       void *saved_ki_complete = NULL;
        int append_write = ((iocb->ki_pos + count) >=
                        i_size_read(inode) ? 1 : 0);
 
@@ -2241,17 +2241,12 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
                goto out;
        }
 
-       if (direct_io && !is_sync_kiocb(iocb))
-               unaligned_dio = ocfs2_is_io_unaligned(inode, count, iocb->ki_pos);
-
-       if (unaligned_dio) {
+       if (direct_io && !is_sync_kiocb(iocb) &&
+           ocfs2_is_io_unaligned(inode, count, iocb->ki_pos)) {
                /*
-                * Wait on previous unaligned aio to complete before
-                * proceeding.
+                * Make it a sync io if it's an unaligned aio.
                 */
-               mutex_lock(&OCFS2_I(inode)->ip_unaligned_aio);
-               /* Mark the iocb as needing an unlock in ocfs2_dio_end_io */
-               ocfs2_iocb_set_unaligned_aio(iocb);
+               saved_ki_complete = xchg(&iocb->ki_complete, NULL);
        }
 
        /* communicate with ocfs2_dio_end_io */
@@ -2272,11 +2267,10 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
         */
        if ((written == -EIOCBQUEUED) || (!ocfs2_iocb_is_rw_locked(iocb))) {
                rw_level = -1;
-               unaligned_dio = 0;
        }
 
        if (unlikely(written <= 0))
-               goto no_sync;
+               goto out;
 
        if (((file->f_flags & O_DSYNC) && !direct_io) ||
            IS_SYNC(inode)) {
@@ -2298,13 +2292,10 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
                                                      iocb->ki_pos - 1);
        }
 
-no_sync:
-       if (unaligned_dio && ocfs2_iocb_is_unaligned_aio(iocb)) {
-               ocfs2_iocb_clear_unaligned_aio(iocb);
-               mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio);
-       }
-
 out:
+       if (saved_ki_complete)
+               xchg(&iocb->ki_complete, saved_ki_complete);
+
        if (rw_level != -1)
                ocfs2_rw_unlock(inode, rw_level);