text: /*
   * 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"
  #include "net.h"
  #include "qdev.h"
  #include "sysemu.h"
  #include "block_int.h"
  #include "event_notifier.h"
  #ifdef CONFIG_LINUX
  #include "9p.h"
  #endif
  
  /* 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
  
  /* Some virtio feature bits (currently bits 28 through 31) are reserved for the
   * transport being used (eg. virtio_ring), the rest are per-device feature bits. */
  #define VIRTIO_TRANSPORT_F_START        28
  #define VIRTIO_TRANSPORT_F_END          32
  
  /* We notify when the ring is completely used, even if the guest is suppressing
   * callbacks */
  #define VIRTIO_F_NOTIFY_ON_EMPTY        24
  /* We support indirect buffer descriptors */
  #define VIRTIO_RING_F_INDIRECT_DESC     28
  /* A guest should never accept this.  It implies negotiation is broken. */
  #define VIRTIO_F_BAD_FEATURE		30
  
  /* 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 the buffer contains a list of buffer descriptors. */
  #define VRING_DESC_F_INDIRECT  4
  
  /* 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;
  
  #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];
      target_phys_addr_t out_addr[VIRTQUEUE_MAX_SIZE];
      struct iovec in_sg[VIRTQUEUE_MAX_SIZE];
      struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
  } VirtQueueElement;
  
  typedef struct {
      void (*notify)(void * opaque, uint16_t vector);
      void (*save_config)(void * opaque, QEMUFile *f);
      void (*save_queue)(void * opaque, int n, QEMUFile *f);
      int (*load_config)(void * opaque, QEMUFile *f);
      int (*load_queue)(void * opaque, int n, QEMUFile *f);
      int (*load_done)(void * opaque, QEMUFile *f);
      unsigned (*get_features)(void * opaque);
      bool (*query_guest_notifiers)(void * opaque);
      int (*set_guest_notifiers)(void * opaque, bool assigned);
      int (*set_host_notifier)(void * opaque, int n, bool assigned);
      void (*vmstate_change)(void * opaque, bool running);
  } VirtIOBindings;
  
  #define VIRTIO_PCI_QUEUE_MAX 64
  
  #define VIRTIO_NO_VECTOR 0xffff
  
  struct VirtIODevice
  {
      const char *name;
      uint8_t status;
      uint8_t isr;
      uint16_t queue_sel;
      uint32_t guest_features;
      size_t config_len;
      void *config;
      uint16_t config_vector;
      int nvectors;
      uint32_t (*get_features)(VirtIODevice *vdev, uint32_t requested_features);
      uint32_t (*bad_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);
      void (*set_status)(VirtIODevice *vdev, uint8_t val);
      VirtQueue *vq;
      const VirtIOBindings *binding;
      void *binding_opaque;
      uint16_t device_id;
      bool vm_running;
      VMChangeStateEntry *vmstate;
  };
  
  static inline void virtio_set_status(VirtIODevice *vdev, uint8_t val)
  {
      if (vdev->set_status) {
          vdev->set_status(vdev, val);
      }
      vdev->status = val;
  }
  
  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);
  
  void virtqueue_map_sg(struct iovec *sg, target_phys_addr_t *addr,
      size_t num_sg, int is_write);
  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);
  
  int virtio_load(VirtIODevice *vdev, QEMUFile *f);
  
  void virtio_cleanup(VirtIODevice *vdev);
  
  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);
  
  /* Host binding interface.  */
  
  VirtIODevice *virtio_common_init(const char *name, uint16_t device_id,
                                   size_t config_size, size_t struct_size);
  uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
  uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
  uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
  void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
  void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
  void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
  void virtio_queue_set_addr(VirtIODevice *vdev, int n, target_phys_addr_t addr);
  target_phys_addr_t virtio_queue_get_addr(VirtIODevice *vdev, int n);
  int virtio_queue_get_num(VirtIODevice *vdev, int n);
  void virtio_queue_notify(VirtIODevice *vdev, int n);
  uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
  void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
  void virtio_reset(void *opaque);
  void virtio_update_irq(VirtIODevice *vdev);
  
  void virtio_bind_device(VirtIODevice *vdev, const VirtIOBindings *binding,
                          void *opaque);
  
  /* Base devices.  */
  VirtIODevice *virtio_blk_init(DeviceState *dev, BlockConf *conf);
  struct virtio_net_conf;
  VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
                                struct virtio_net_conf *net);
  VirtIODevice *virtio_serial_init(DeviceState *dev, uint32_t max_nr_ports);
  VirtIODevice *virtio_balloon_init(DeviceState *dev);
  #ifdef CONFIG_LINUX
  VirtIODevice *virtio_9p_init(DeviceState *dev, V9fsConf *conf);
  #endif
  
  
  void virtio_net_exit(VirtIODevice *vdev);
  void virtio_blk_exit(VirtIODevice *vdev);
  void virtio_serial_exit(VirtIODevice *vdev);
  
  #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
  	DEFINE_PROP_BIT("indirect_desc", _state, _field, \
  			VIRTIO_RING_F_INDIRECT_DESC, true)
  
  target_phys_addr_t virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
  target_phys_addr_t virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
  target_phys_addr_t virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
  target_phys_addr_t virtio_queue_get_ring_addr(VirtIODevice *vdev, int n);
  target_phys_addr_t virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
  target_phys_addr_t virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
  target_phys_addr_t virtio_queue_get_used_size(VirtIODevice *vdev, int n);
  target_phys_addr_t virtio_queue_get_ring_size(VirtIODevice *vdev, int n);
  uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
  void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx);
  VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
  EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
  EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
  void virtio_queue_notify_vq(VirtQueue *vq);
  void virtio_irq(VirtQueue *vq);
  #endif
  