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 <hch@xxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
---
fs/aio.c | 6 ------
fs/btrfs/file.c | 6 +++++-
fs/ext4/file.c | 6 +++---
fs/xfs/xfs_file.c | 11 +++++++++--
include/linux/fs.h | 6 +++---
5 files changed, 20 insertions(+), 15 deletions(-)
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 @@ static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int whence)
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;
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 6e1fd5d21248..ded258edc425 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -146,8 +146,8 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
/* File was opened by fanotify and shouldn't generate fanotify events */
#define FMODE_NONOTIFY ((__force fmode_t)0x4000000)
-/* File is capable of returning -EAGAIN if AIO will block */
-#define FMODE_AIO_NOWAIT ((__force fmode_t)0x8000000)
+/* File is capable of returning -EAGAIN if I/O will block */
+#define FMODE_NOWAIT ((__force fmode_t)0x8000000)
/*
* Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
@@ -3149,7 +3149,7 @@ static inline int kiocb_set_rw_flags(struct kiocb *ki, int flags)
return -EOPNOTSUPP;
if (flags & RWF_NOWAIT) {
- if (!(ki->ki_filp->f_mode & FMODE_AIO_NOWAIT))
+ if (!(ki->ki_filp->f_mode & FMODE_NOWAIT))
return -EOPNOTSUPP;
ki->ki_flags |= IOCB_NOWAIT;
}
--
2.11.0
