From 91f9943e1c7b6638f27312d03fe71fcc67b23571 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 29 Aug 2017 16:13:20 +0200 Subject: fs: support RWF_NOWAIT for buffered reads This is based on the old idea and code from Milosz Tanski. With the aio nowait code it becomes mostly trivial now. Buffered writes continue to return -EOPNOTSUPP if RWF_NOWAIT is passed. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Al Viro --- fs/xfs/xfs_file.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'fs/xfs') diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index c4893e226fd8e..1a09104b3eb03 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -259,7 +259,11 @@ xfs_file_buffered_aio_read( trace_xfs_file_buffered_read(ip, iov_iter_count(to), iocb->ki_pos); - xfs_ilock(ip, XFS_IOLOCK_SHARED); + if (!xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED)) { + if (iocb->ki_flags & IOCB_NOWAIT) + return -EAGAIN; + xfs_ilock(ip, XFS_IOLOCK_SHARED); + } ret = generic_file_read_iter(iocb, to); xfs_iunlock(ip, XFS_IOLOCK_SHARED); @@ -636,6 +640,9 @@ xfs_file_buffered_aio_write( int enospc = 0; int iolock; + if (iocb->ki_flags & IOCB_NOWAIT) + return -EOPNOTSUPP; + write_retry: iolock = XFS_IOLOCK_EXCL; xfs_ilock(ip, iolock); @@ -912,7 +919,7 @@ xfs_file_open( return -EFBIG; if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb))) return -EIO; - file->f_mode |= FMODE_AIO_NOWAIT; + file->f_mode |= FMODE_NOWAIT; return 0; } -- cgit v1.2.3