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/aio.c | 6 ------ fs/btrfs/file.c | 6 +++++- fs/ext4/file.c | 6 +++--- fs/xfs/xfs_file.c | 11 +++++++++-- 4 files changed, 17 insertions(+), 12 deletions(-) (limited to 'fs') diff --git a/fs/aio.c b/fs/aio.c index dcad3a66748c..d93daa076726 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1593,12 +1593,6 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, goto out_put_req; } - if ((req->common.ki_flags & IOCB_NOWAIT) && - !(req->common.ki_flags & IOCB_DIRECT)) { - ret = -EOPNOTSUPP; - goto out_put_req; - } - ret = put_user(KIOCB_KEY, &user_iocb->aio_key); if (unlikely(ret)) { pr_debug("EFAULT: aio_key\n"); diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 9e75d8a39aac..e62dd55b4079 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1886,6 +1886,10 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, loff_t oldsize; int clean_page = 0; + if (!(iocb->ki_flags & IOCB_DIRECT) && + (iocb->ki_flags & IOCB_NOWAIT)) + return -EOPNOTSUPP; + if (!inode_trylock(inode)) { if (iocb->ki_flags & IOCB_NOWAIT) return -EAGAIN; @@ -3105,7 +3109,7 @@ out: static int btrfs_file_open(struct inode *inode, struct file *filp) { - filp->f_mode |= FMODE_AIO_NOWAIT; + filp->f_mode |= FMODE_NOWAIT; return generic_file_open(inode, filp); } diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 0d7cf0cc9b87..f83521337b8f 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -223,6 +223,8 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) if (IS_DAX(inode)) return ext4_dax_write_iter(iocb, from); #endif + if (!o_direct && (iocb->ki_flags & IOCB_NOWAIT)) + return -EOPNOTSUPP; if (!inode_trylock(inode)) { if (iocb->ki_flags & IOCB_NOWAIT) @@ -448,9 +450,7 @@ static int ext4_file_open(struct inode * inode, struct file * filp) return ret; } - /* Set the flags to support nowait AIO */ - filp->f_mode |= FMODE_AIO_NOWAIT; - + filp->f_mode |= FMODE_NOWAIT; return dquot_file_open(inode, filp); } diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index c4893e226fd8..1a09104b3eb0 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 From c35fc7a5abae9c154dd6f8c0b288462342facd45 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 29 Aug 2017 16:13:21 +0200 Subject: block_dev: support RFW_NOWAIT on block device nodes All support is already there in the generic code, we just need to wire it up. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Al Viro --- fs/block_dev.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs') diff --git a/fs/block_dev.c b/fs/block_dev.c index 9941dc8342df..ea21d18d8e79 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -1739,6 +1739,8 @@ static int blkdev_open(struct inode * inode, struct file * filp) */ filp->f_flags |= O_LARGEFILE; + filp->f_mode |= FMODE_NOWAIT; + if (filp->f_flags & O_NDELAY) filp->f_mode |= FMODE_NDELAY; if (filp->f_flags & O_EXCL) @@ -1891,6 +1893,9 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) if (iocb->ki_pos >= size) return -ENOSPC; + if ((iocb->ki_flags & (IOCB_NOWAIT | IOCB_DIRECT)) == IOCB_NOWAIT) + return -EOPNOTSUPP; + iov_iter_truncate(from, size - iocb->ki_pos); blk_start_plug(&plug); -- cgit v1.2.3