[PATCH RFC v6 08/16] fuse: Add fuse-io-uring handling into fuse_copy

[Bernd Schubert <bschubert@ddn.com>]

Add special fuse-io-uring into the fuse argument
copy handler.

Signed-off-by: Bernd Schubert <bschubert@ddn.com>
---
 fs/fuse/dev.c         | 12 +++++++++++-
 fs/fuse/dev_uring_i.h |  6 +++---
 fs/fuse/fuse_dev_i.h  |  5 +++++
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index aa654989d768df3dd82690ef071bbe0aa87817b0..ad65ede9c7723bb6f3589e64b8eef7429fa4b488 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -787,6 +787,9 @@ static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
 	*size -= ncpy;
 	cs->len -= ncpy;
 	cs->offset += ncpy;
+	if (cs->is_uring)
+		cs->ring.offset += ncpy;
+
 	return ncpy;
 }
 
@@ -1926,7 +1929,14 @@ static struct fuse_req *request_find(struct fuse_pqueue *fpq, u64 unique)
 int fuse_copy_out_args(struct fuse_copy_state *cs, struct fuse_args *args,
 		       unsigned nbytes)
 {
-	unsigned reqsize = sizeof(struct fuse_out_header);
+
+	unsigned int reqsize = 0;
+
+	/*
+	 * Uring has all headers separated from args - args is payload only
+	 */
+	if (!cs->is_uring)
+		reqsize = sizeof(struct fuse_out_header);
 
 	reqsize += fuse_len_args(args->out_numargs, args->out_args);
 
diff --git a/fs/fuse/dev_uring_i.h b/fs/fuse/dev_uring_i.h
index fab6f2a6c14b9de0aa8ec525ab17e59315c31e6a..17767e373d31969fe2987fed31c66b5077f209c6 100644
--- a/fs/fuse/dev_uring_i.h
+++ b/fs/fuse/dev_uring_i.h
@@ -14,13 +14,13 @@
 enum fuse_ring_req_state {
 	FRRS_INVALID = 0,
 
-	/* ring entry received from userspace and it being processed */
+	/* The ring entry received from userspace and it being processed */
 	FRRS_COMMIT,
 
-	/* The ring request waits for a new fuse request */
+	/* The ring entry is waiting for new fuse requests */
 	FRRS_WAIT,
 
-	/* request is in or on the way to user space */
+	/* The ring entry is in or on the way to user space */
 	FRRS_USERSPACE,
 };
 
diff --git a/fs/fuse/fuse_dev_i.h b/fs/fuse/fuse_dev_i.h
index f36e304cd62c8302aed95de89926fc894f602cfd..7ecb103af6f0feca99eb8940872c6a5ccf2e5186 100644
--- a/fs/fuse/fuse_dev_i.h
+++ b/fs/fuse/fuse_dev_i.h
@@ -28,6 +28,11 @@ struct fuse_copy_state {
 	unsigned int len;
 	unsigned int offset;
 	unsigned int move_pages:1;
+	unsigned int is_uring:1;
+	struct {
+		/* overall offset with the user buffer */
+		unsigned int offset;
+	} ring;
 };
 
 static inline struct fuse_dev *fuse_get_dev(struct file *file)

-- 
2.43.0