virtio: Store queue descriptors in virtio_device

At the moment desc/avail/used pointers are read from the device every
time we need them. This works for now unless iommu_platform=on is used,
desc/avail/used stored in the config space are bus addresses while
SLOF should keep using the guest physical addresses.

virtio-net stores queue descriptors already, virtio-serial does it in
global statics, move them into virtio_device.

The next patch will use this to allow IOMMU.

While at this, move repeating avail->flags/idx setup into
virtio_queue_init_vq() except virtio-serial which vq_rx->avail->idx is
setup differently.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
Changes:
v4:
* removed vqs::id as it is not really used
* replaced vq_size with vq->size in virtio-serial.c

1 files changed, 12 insertions, 13 deletions

diff --git a/lib/libvirtio/virtio.h b/lib/libvirtio/virtio.h
index b65c716..7efc1e5 100644
--- a/lib/libvirtio/virtio.h
+++ b/lib/libvirtio/virtio.h
@@ -14,7 +14,6 @@
 #define _LIBVIRTIO_H
 
 #include <stdint.h>
-#include <stdbool.h>
 
 /* Device status bits */
 #define VIRTIO_STAT_ACKNOWLEDGE		1
@@ -78,8 +77,16 @@ struct virtio_cap {
 	uint8_t cap_id;
 };
 
+struct vqs {
+	uint32_t size;
+	void *buf_mem;
+	struct vring_desc *desc;
+	struct vring_avail *avail;
+	struct vring_used *used;
+};
+
 struct virtio_device {
-	uint32_t is_modern;     /* Indicates whether to use virtio 1.0 */
+	uint64_t features;
 	struct virtio_cap legacy;
 	struct virtio_cap common;
 	struct virtio_cap notify;
@@ -87,15 +94,7 @@ struct virtio_device {
 	struct virtio_cap device;
 	struct virtio_cap pci;
 	uint32_t notify_off_mul;
-};
-
-struct vqs {
-	uint64_t id;	/* Queue ID */
-	uint32_t size;
-	void *buf_mem;
-	struct vring_desc *desc;
-	struct vring_avail *avail;
-	struct vring_used *used;
+	struct vqs vq[3];
 };
 
 /* Parts of the virtqueue are aligned on a 4096 byte page boundary */
@@ -106,10 +105,10 @@ extern unsigned int virtio_get_qsize(struct virtio_device *dev, int queue);
 extern struct vring_desc *virtio_get_vring_desc(struct virtio_device *dev, int queue);
 extern struct vring_avail *virtio_get_vring_avail(struct virtio_device *dev, int queue);
 extern struct vring_used *virtio_get_vring_used(struct virtio_device *dev, int queue);
-extern void virtio_fill_desc(struct vring_desc *desc, bool is_modern,
+extern void virtio_fill_desc(struct vqs *vq, int id, uint64_t features,
                              uint64_t addr, uint32_t len,
                              uint16_t flags, uint16_t next);
-extern int virtio_queue_init_vq(struct virtio_device *dev, struct vqs *vq, unsigned int id);
+extern struct vqs *virtio_queue_init_vq(struct virtio_device *dev, unsigned int id);
 extern void virtio_queue_term_vq(struct virtio_device *dev, struct vqs *vq, unsigned int id);
 
 extern struct virtio_device *virtio_setup_vd(void);