/*

 * Virtio Support

 *

 * Copyright IBM, Corp. 2007

 *

 * Authors:

 *  Anthony Liguori   <aliguori@us.ibm.com>

 *

 * This work is licensed under the terms of the GNU GPL, version 2.  See

 * the COPYING file in the top-level directory.

 *

 */

#ifndef _QEMU_VIRTIO_H

#define _QEMU_VIRTIO_H

#include "hw.h"

/* from Linux's linux/virtio_config.h */

/* Status byte for guest to report progress, and synchronize features. */

/* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */

#define VIRTIO_CONFIG_S_ACKNOWLEDGE     1

/* We have found a driver for the device. */

#define VIRTIO_CONFIG_S_DRIVER          2

/* Driver has used its parts of the config, and is happy */

#define VIRTIO_CONFIG_S_DRIVER_OK       4

/* We've given up on this device. */

#define VIRTIO_CONFIG_S_FAILED          0x80

/* We notify when the ring is completely used, even if the guest is supressing

 * callbacks */

#define VIRTIO_F_NOTIFY_ON_EMPTY        24

/* from Linux's linux/virtio_ring.h */

/* This marks a buffer as continuing via the next field. */

#define VRING_DESC_F_NEXT       1

/* This marks a buffer as write-only (otherwise read-only). */

#define VRING_DESC_F_WRITE      2

/* This means don't notify other side when buffer added. */

#define VRING_USED_F_NO_NOTIFY  1

/* This means don't interrupt guest when buffer consumed. */

#define VRING_AVAIL_F_NO_INTERRUPT      1

struct VirtQueue;

static inline target_phys_addr_t vring_align(target_phys_addr_t addr,

                                             unsigned long align)

{

    return (addr + align - 1) & ~(align - 1);

}

typedef struct VirtQueue VirtQueue;

typedef struct VirtIODevice VirtIODevice;

#define VIRTQUEUE_MAX_SIZE 1024

typedef struct VirtQueueElement

{

    unsigned int index;

    unsigned int out_num;

    unsigned int in_num;

    target_phys_addr_t in_addr[VIRTQUEUE_MAX_SIZE];

    struct iovec in_sg[VIRTQUEUE_MAX_SIZE];

    struct iovec out_sg[VIRTQUEUE_MAX_SIZE];

} VirtQueueElement;

#define VIRTIO_PCI_QUEUE_MAX 16

struct VirtIODevice

{

    const char *name;

    uint32_t addr;

    uint8_t status;

    uint8_t isr;

    uint16_t queue_sel;

    uint32_t features;

    size_t config_len;

    void *config;

    uint32_t (*get_features)(VirtIODevice *vdev);

    void (*set_features)(VirtIODevice *vdev, uint32_t val);

    void (*get_config)(VirtIODevice *vdev, uint8_t *config);

    void (*set_config)(VirtIODevice *vdev, const uint8_t *config);

    void (*reset)(VirtIODevice *vdev);

    VirtQueue *vq;

    /* Bus binding callbacks.  */

    void *binding_dev;

    void (*update_irq)(VirtIODevice *vdev);

    void (*save_binding)(VirtIODevice *vdev, QEMUFile *f);

    void (*load_binding)(VirtIODevice *vdev, QEMUFile *f);

};

typedef VirtIODevice *(*VirtIOBindFn)(void *args, const char *name,

                                      uint16_t vendor, uint16_t device,

                                      size_t config_size, size_t struct_size);

VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,

                            void (*handle_output)(VirtIODevice *,

                                                  VirtQueue *));

void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,

                    unsigned int len);

void virtqueue_flush(VirtQueue *vq, unsigned int count);

void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,

                    unsigned int len, unsigned int idx);

int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem);

int virtqueue_avail_bytes(VirtQueue *vq, int in_bytes, int out_bytes);

void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);

void virtio_save(VirtIODevice *vdev, QEMUFile *f);

void virtio_load(VirtIODevice *vdev, QEMUFile *f);

void virtio_notify_config(VirtIODevice *vdev);

void virtio_queue_set_notification(VirtQueue *vq, int enable);

int virtio_queue_ready(VirtQueue *vq);

int virtio_queue_empty(VirtQueue *vq);

/* Functions for use by VirtIO bus bindings.  */

VirtIODevice *virtio_init_common(const char *name, size_t config_size,

                                 size_t struct_size);

void virtio_set_vring_addr(VirtIODevice *vdev, int n, target_phys_addr_t pa);

target_phys_addr_t virtio_get_vring_pa(VirtIODevice *vdev, int n);

target_phys_addr_t virtio_get_vring_num(VirtIODevice *vdev, int n);

void virtio_kick(VirtIODevice *vdev, int n);

void virtio_reset(void *opaque);

uint32_t virtio_config_readb(void *opaque, uint32_t addr);

uint32_t virtio_config_readw(void *opaque, uint32_t addr);

uint32_t virtio_config_readl(void *opaque, uint32_t addr);

void virtio_config_writeb(void *opaque, uint32_t addr, uint32_t data);

void virtio_config_writew(void *opaque, uint32_t addr, uint32_t data);

void virtio_config_writel(void *opaque, uint32_t addr, uint32_t data);

static inline void virtio_update_irq(VirtIODevice *dev)

{

    dev->update_irq(dev);

}

#endif