import RT-Thread@9217865c without bsp, libcpu and components/net

components/drivers/virtio/virtio_queue.h

@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2006-2023, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-11-11     GuEe-GUI     the first version
+ */
+
+#ifndef __VIRTIO_QUEUE_H__
+#define __VIRTIO_QUEUE_H__
+
+#include <rtdef.h>
+
+#define VIRTQ_DESC_F_NEXT           1 /* This marks a buffer as continuing via the next field. */
+#define VIRTQ_DESC_F_WRITE          2 /* This marks a buffer as write-only (otherwise read-only). */
+#define VIRTQ_DESC_F_INDIRECT       4 /* This means the buffer contains a list of buffer descriptors. */
+
+/*
+ * The device uses this in used->flags to advise the driver: don't kick me
+ * when you add a buffer.  It's unreliable, so it's simply an optimization.
+ */
+#define VIRTQ_USED_F_NO_NOTIFY      1
+
+/*
+ * The driver uses this in avail->flags to advise the device: don't
+ * interrupt me when you consume a buffer.  It's unreliable, so it's
+ * simply an optimization.
+ */
+#define VIRTQ_AVAIL_F_NO_INTERRUPT  1
+
+/* Virtqueue descriptors: 16 bytes. These can chain together via "next". */
+struct virtq_desc
+{
+    rt_uint64_t addr;   /* Address (guest-physical). */
+    rt_uint32_t len;    /* Length. */
+    rt_uint16_t flags;  /* The flags as indicated above. */
+    rt_uint16_t next;   /* We chain unused descriptors via this, too */
+};
+
+struct virtq_avail
+{
+    rt_uint16_t flags;  /* Notifications */
+    rt_uint16_t idx;    /* Where the driver would put the next descriptor entry in the ring (modulo the queue size) */
+    rt_uint16_t ring[];
+
+    /*
+     * Only if VIRTIO_F_RING_EVENT_IDX
+     * rt_uint16_t used_event;
+     */
+};
+
+struct virtq_used_elem
+{
+    rt_uint32_t id;     /* Index of start of used descriptor chain. */
+    rt_uint32_t len;    /* Total length of the descriptor chain which was written to. */
+};
+
+struct virtq_used
+{
+    rt_uint16_t flags;
+    rt_uint16_t idx;
+    struct virtq_used_elem ring[];
+
+    /*
+     * Only if VIRTIO_F_RING_EVENT_IDX
+     * rt_uint16_t avail_event;
+     */
+};
+
+struct virtq
+{
+    rt_uint32_t num;
+
+    struct virtq_desc *desc;
+    struct virtq_avail *avail;
+    struct virtq_used *used;
+
+    /* Helper of driver */
+    rt_uint16_t used_idx;
+    rt_bool_t *free;
+    rt_size_t free_count;
+};
+
+#define VIRTQ_DESC_TOTAL_SIZE(ring_size)    (sizeof(struct virtq_desc) * (ring_size))
+/* flags, idx, used_event + ring * ring_size */
+#define VIRTQ_AVAIL_TOTAL_SIZE(ring_size)   (sizeof(rt_uint16_t) * 3 + sizeof(rt_uint16_t) * (ring_size))
+/* flags, idx, avail_event + ring * ring_size */
+#define VIRTQ_USED_TOTAL_SIZE(ring_size)    (sizeof(rt_uint16_t) * 3 + sizeof(struct virtq_used_elem) * (ring_size))
+
+#define VIRTQ_AVAIL_RES_SIZE    (sizeof(rt_uint16_t))   /* used_event */
+#define VIRTQ_USED_RES_SIZE     (sizeof(rt_uint16_t))   /* avail_event */
+
+#define VIRTQ_INVALID_DESC_ID   RT_UINT16_MAX
+
+#endif /* __VIRTIO_QUEUE_H__ */