diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 1f2e2845eb76..a7ceae90110e 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -529,18 +529,17 @@ xfs_file_dio_aio_write( count = iov_iter_count(from); /* - * If we are doing unaligned IO, wait for all other IO to drain, - * otherwise demote the lock if we had to take the exclusive lock - * for other reasons in xfs_file_aio_write_checks. + * If we are doing unaligned IO, we can't allow any other overlapping IO + * in-flight at the same time or we risk data corruption. Wait for all + * other IO to drain before we submit. If the IO is aligned, demote the + * iolock if we had to take the exclusive lock in + * xfs_file_aio_write_checks() for other reasons. */ if (unaligned_io) { - /* If we are going to wait for other DIO to finish, bail */ - if (iocb->ki_flags & IOCB_NOWAIT) { - if (atomic_read(&inode->i_dio_count)) - return -EAGAIN; - } else { - inode_dio_wait(inode); - } + /* unaligned dio always waits, bail */ + if (iocb->ki_flags & IOCB_NOWAIT) + return -EAGAIN; + inode_dio_wait(inode); } else if (iolock == XFS_IOLOCK_EXCL) { xfs_ilock_demote(ip, XFS_IOLOCK_EXCL); iolock = XFS_IOLOCK_SHARED; @@ -548,6 +547,14 @@ xfs_file_dio_aio_write( trace_xfs_file_direct_write(ip, count, iocb->ki_pos); ret = iomap_dio_rw(iocb, from, &xfs_iomap_ops, xfs_dio_write_end_io); + + /* + * If unaligned, this is the only IO in-flight. If it has not yet + * completed, wait on it before we release the iolock to prevent + * subsequent overlapping IO. + */ + if (ret == -EIOCBQUEUED && unaligned_io) + inode_dio_wait(inode); out: xfs_iunlock(ip, iolock);