[PATCH] fuse: Dont set_page_dirty_lock() for ITER_BVEC pages for async_dio

[Ashish Samant <ashish.samant@xxxxxxxxxx>]

'Commit 8fba54aebbdf ("fuse: direct-io: don't dirty ITER_BVEC pages")'
fixes the ITER_BVEC page deadlock for direct io in fuse but misses the
async_dio case.

Fix this by making should_dirty a fuse_io_priv parameter.

Reported-by: Tiger Yang <tiger.yang@xxxxxxxxxx>
Signed-off-by: Ashish Samant <ashish.samant@xxxxxxxxxx>
---
 fs/fuse/file.c   | 8 +++++---
 fs/fuse/fuse_i.h | 2 ++
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 3ee4fdc..e865ac7 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -608,8 +608,9 @@ static void fuse_aio_complete_req(struct fuse_conn *fc, struct fuse_req *req)
 {
 	struct fuse_io_priv *io = req->io;
 	ssize_t pos = -1;
+	bool should_dirty = io->should_dirty && !io->write;
 
-	fuse_release_user_pages(req, !io->write);
+	fuse_release_user_pages(req, should_dirty);
 
 	if (io->write) {
 		if (req->misc.write.in.size != req->misc.write.out.size)
@@ -1316,7 +1317,6 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
 		       loff_t *ppos, int flags)
 {
 	int write = flags & FUSE_DIO_WRITE;
-	bool should_dirty = !write && iter_is_iovec(iter);
 	int cuse = flags & FUSE_DIO_CUSE;
 	struct file *file = io->file;
 	struct inode *inode = file->f_mapping->host;
@@ -1346,6 +1346,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
 			inode_unlock(inode);
 	}
 
+	io->should_dirty = !write && iter_is_iovec(iter);
 	while (count) {
 		size_t nres;
 		fl_owner_t owner = current->files;
@@ -1360,7 +1361,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
 			nres = fuse_send_read(req, io, pos, nbytes, owner);
 
 		if (!io->async)
-			fuse_release_user_pages(req, should_dirty);
+			fuse_release_user_pages(req, io->should_dirty);
 		if (req->out.h.error) {
 			err = req->out.h.error;
 			break;
@@ -2872,6 +2873,7 @@ static inline loff_t fuse_round_up(loff_t off)
 	io->size = 0;
 	io->offset = offset;
 	io->write = (iov_iter_rw(iter) == WRITE);
+	io->should_dirty = true;
 	io->err = 0;
 	io->file = file;
 	/*
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 1bd7ffd..2ef205e 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -249,6 +249,7 @@ struct fuse_io_priv {
 	size_t size;
 	__u64 offset;
 	bool write;
+	bool should_dirty;
 	int err;
 	struct kiocb *iocb;
 	struct file *file;
@@ -261,6 +262,7 @@ struct fuse_io_priv {
 	.refcnt = KREF_INIT(1),		\
 	.async = 0,			\
 	.file = f,			\
+	.should_dirty = true,           \
 }
 
 /**
-- 
1.9.1