explicitly tell iomap to do it, rather than messing with IOCB_DSYNC
[folded a fix for braino spotted by willy]
Suggested-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/btrfs/file.c | 17 -----------------
fs/btrfs/inode.c | 2 +-
fs/iomap/direct-io.c | 2 +-
include/linux/iomap.h | 2 ++
4 files changed, 4 insertions(+), 19 deletions(-)
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 1fd827b99c1b..98f81e304eb1 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1848,7 +1848,6 @@ static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info,
static ssize_t btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)
{
- const bool is_sync_write = (iocb->ki_flags & IOCB_DSYNC);
struct file *file = iocb->ki_filp;
struct inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
@@ -1901,15 +1900,6 @@ static ssize_t btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)
goto buffered;
}
- /*
- * We remove IOCB_DSYNC so that we don't deadlock when iomap_dio_rw()
- * calls generic_write_sync() (through iomap_dio_complete()), because
- * that results in calling fsync (btrfs_sync_file()) which will try to
- * lock the inode in exclusive/write mode.
- */
- if (is_sync_write)
- iocb->ki_flags &= ~IOCB_DSYNC;
-
/*
* The iov_iter can be mapped to the same file range we are writing to.
* If that's the case, then we will deadlock in the iomap code, because
@@ -1964,13 +1954,6 @@ static ssize_t btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)
btrfs_inode_unlock(inode, ilock_flags);
- /*
- * Add back IOCB_DSYNC. Our caller, btrfs_file_write_iter(), will do
- * the fsync (call generic_write_sync()).
- */
- if (is_sync_write)
- iocb->ki_flags |= IOCB_DSYNC;
-
/* If 'err' is -ENOTBLK then it means we must fallback to buffered IO. */
if ((err < 0 && err != -ENOTBLK) || !iov_iter_count(from))
goto out;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 81737eff92f3..c9c8f49568d1 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8152,7 +8152,7 @@ ssize_t btrfs_dio_rw(struct kiocb *iocb, struct iov_iter *iter, size_t done_befo
struct btrfs_dio_data data;
return iomap_dio_rw(iocb, iter, &btrfs_dio_iomap_ops, &btrfs_dio_ops,
- IOMAP_DIO_PARTIAL, &data, done_before);
+ IOMAP_DIO_PARTIAL | IOMAP_DIO_NOSYNC, &data, done_before);
}
static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 370c3241618a..0f16479b13d6 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -548,7 +548,7 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
}
/* for data sync or sync, we need sync completion processing */
- if (iocb->ki_flags & IOCB_DSYNC)
+ if (iocb->ki_flags & IOCB_DSYNC && !(dio_flags & IOMAP_DIO_NOSYNC))
dio->flags |= IOMAP_DIO_NEED_SYNC;
/*
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index e552097c67e0..95de0c771d37 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -353,6 +353,8 @@ struct iomap_dio_ops {
*/
#define IOMAP_DIO_PARTIAL (1 << 2)
+#define IOMAP_DIO_NOSYNC (1 << 3)
+
ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
const struct iomap_ops *ops, const struct iomap_dio_ops *dops,
unsigned int dio_flags, void *private, size_t done_before);
--
2.30.2
