Merge branch 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull nowait read support from Al Viro:
 "Support IOCB_NOWAIT for buffered reads and block devices"

* 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  block_dev: support RFW_NOWAIT on block device nodes
  fs: support RWF_NOWAIT for buffered reads
  fs: support IOCB_NOWAIT in generic_file_buffered_read
  fs: pass iocb to do_generic_file_read

5 files changed, 22 insertions, 12 deletions

diff --git a/fs/aio.c b/fs/aio.c
index b5d69f28d8b1..5a2487217072 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1606,12 +1606,6 @@ 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/block_dev.c b/fs/block_dev.c
index bb715b2fcfb8..93d088ffc05c 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1740,6 +1740,8 @@ 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)
@@ -1892,6 +1894,9 @@ 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);
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 74fd7756cff3..aafcc785f840 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;
@@ -3112,7 +3116,7 @@ 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 da9c6948ad25..b1da660ac3bc 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)
@@ -431,9 +433,7 @@ 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 ec3e44fcf771..ebdd0bd2b261 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;
 }