[PATCH RFC v3 06/17] fuse: Add the queue configuration ioctl

[Bernd Schubert <bschubert@ddn.com>]

Signed-off-by: Bernd Schubert <bschubert@ddn.com>
---
 fs/fuse/dev.c             | 30 ++++++++++++++++++++++++++++++
 fs/fuse/dev_uring.c       |  2 ++
 fs/fuse/dev_uring_i.h     | 13 +++++++++++++
 fs/fuse/fuse_i.h          |  4 ++++
 include/uapi/linux/fuse.h | 39 +++++++++++++++++++++++++++++++++++++++
 5 files changed, 88 insertions(+)

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 6489179e7260..06ea4dc5ffe1 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -2379,6 +2379,33 @@ static long fuse_dev_ioctl_backing_close(struct file *file, __u32 __user *argp)
 	return fuse_backing_close(fud->fc, backing_id);
 }
 
+#ifdef CONFIG_FUSE_IO_URING
+static long fuse_uring_queue_ioc(struct file *file, __u32 __user *argp)
+{
+	int res = 0;
+	struct fuse_dev *fud;
+	struct fuse_conn *fc;
+	struct fuse_ring_queue_config qcfg;
+
+	res = copy_from_user(&qcfg, (void *)argp, sizeof(qcfg));
+	if (res != 0)
+		return -EFAULT;
+
+	res = _fuse_dev_ioctl_clone(file, qcfg.control_fd);
+	if (res != 0)
+		return res;
+
+	fud = fuse_get_dev(file);
+	if (fud == NULL)
+		return -ENODEV;
+	fc = fud->fc;
+
+	fud->ring_q = fuse_uring_get_queue(fc->ring, qcfg.qid);
+
+	return 0;
+}
+#endif
+
 static long
 fuse_dev_ioctl(struct file *file, unsigned int cmd,
 	       unsigned long arg)
@@ -2398,6 +2425,9 @@ fuse_dev_ioctl(struct file *file, unsigned int cmd,
 #ifdef CONFIG_FUSE_IO_URING
 	case FUSE_DEV_IOC_URING_CFG:
 		return fuse_uring_conn_cfg(file, argp);
+
+	case FUSE_DEV_IOC_URING_QUEUE_CFG:
+		return fuse_uring_queue_ioc(file, argp);
 #endif
 	default:
 		return -ENOTTY;
diff --git a/fs/fuse/dev_uring.c b/fs/fuse/dev_uring.c
index 4e7518ef6527..4dcb4972242e 100644
--- a/fs/fuse/dev_uring.c
+++ b/fs/fuse/dev_uring.c
@@ -42,6 +42,8 @@ static void fuse_uring_queue_cfg(struct fuse_ring_queue *queue, int qid,
 
 		ent->queue = queue;
 		ent->tag = tag;
+
+		ent->state = FRRS_INIT;
 	}
 }
 
diff --git a/fs/fuse/dev_uring_i.h b/fs/fuse/dev_uring_i.h
index d4eff87bcd1f..301b37d16506 100644
--- a/fs/fuse/dev_uring_i.h
+++ b/fs/fuse/dev_uring_i.h
@@ -14,6 +14,13 @@
 /* IORING_MAX_ENTRIES */
 #define FUSE_URING_MAX_QUEUE_DEPTH 32768
 
+enum fuse_ring_req_state {
+
+	/* request is basially initialized */
+	FRRS_INIT = 1,
+
+};
+
 /* A fuse ring entry, part of the ring queue */
 struct fuse_ring_ent {
 	/* back pointer */
@@ -21,6 +28,12 @@ struct fuse_ring_ent {
 
 	/* array index in the ring-queue */
 	unsigned int tag;
+
+	/*
+	 * state the request is currently in
+	 * (enum fuse_ring_req_state)
+	 */
+	unsigned long state;
 };
 
 struct fuse_ring_queue {
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 33e81b895fee..5eb8552d9d7f 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -540,6 +540,10 @@ struct fuse_dev {
 
 	/** list entry on fc->devices */
 	struct list_head entry;
+
+#ifdef CONFIG_FUSE_IO_URING
+	struct fuse_ring_queue *ring_q;
+#endif
 };
 
 enum fuse_dax_mode {
diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h
index a1c35e0338f0..143ed3c1c7b3 100644
--- a/include/uapi/linux/fuse.h
+++ b/include/uapi/linux/fuse.h
@@ -1118,6 +1118,18 @@ struct fuse_ring_config {
 	uint8_t padding[64];
 };
 
+struct fuse_ring_queue_config {
+	/* qid the command is for */
+	uint32_t qid;
+
+	/* /dev/fuse fd that initiated the mount. */
+	uint32_t control_fd;
+
+	/* for future extensions */
+	uint8_t padding[64];
+};
+
+
 /* Device ioctls: */
 #define FUSE_DEV_IOC_MAGIC		229
 #define FUSE_DEV_IOC_CLONE		_IOR(FUSE_DEV_IOC_MAGIC, 0, uint32_t)
@@ -1126,6 +1138,8 @@ struct fuse_ring_config {
 #define FUSE_DEV_IOC_BACKING_CLOSE	_IOW(FUSE_DEV_IOC_MAGIC, 2, uint32_t)
 #define FUSE_DEV_IOC_URING_CFG		_IOR(FUSE_DEV_IOC_MAGIC, 3, \
 					     struct fuse_ring_config)
+#define FUSE_DEV_IOC_URING_QUEUE_CFG	_IOR(FUSE_DEV_IOC_MAGIC, 3, \
+					     struct fuse_ring_queue_config)
 
 struct fuse_lseek_in {
 	uint64_t	fh;
@@ -1233,4 +1247,29 @@ struct fuse_supp_groups {
 #define FUSE_RING_HEADER_BUF_SIZE 4096
 #define FUSE_RING_MIN_IN_OUT_ARG_SIZE 4096
 
+/**
+ * This structure mapped onto the
+ */
+struct fuse_ring_req {
+	union {
+		/* The first 4K are command data */
+		char ring_header[FUSE_RING_HEADER_BUF_SIZE];
+
+		struct {
+			uint64_t flags;
+
+			uint32_t in_out_arg_len;
+			uint32_t padding;
+
+			/* kernel fills in, reads out */
+			union {
+				struct fuse_in_header in;
+				struct fuse_out_header out;
+			};
+		};
+	};
+
+	char in_out_arg[];
+};
+
 #endif /* _LINUX_FUSE_H */

-- 
2.43.0