text: /*
   * Virtio Support
   *
   * Copyright IBM, Corp. 2007-2008
   *
   * Authors:
   *  Anthony Liguori   <aliguori@us.ibm.com>
   *  Rusty Russell     <rusty@rustcorp.com.au>
   *
   * 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_BALLOON_H
  #define QEMU_VIRTIO_BALLOON_H
  
  #include "standard-headers/linux/virtio_balloon.h"
  #include "hw/virtio/virtio.h"
  #include "sysemu/iothread.h"
  
  #define TYPE_VIRTIO_BALLOON "virtio-balloon-device"
  #define VIRTIO_BALLOON(obj) \
          OBJECT_CHECK(VirtIOBalloon, (obj), TYPE_VIRTIO_BALLOON)
  
  #define VIRTIO_BALLOON_FREE_PAGE_REPORT_CMD_ID_MIN 0x80000000
  
  typedef struct virtio_balloon_stat VirtIOBalloonStat;
  
  typedef struct virtio_balloon_stat_modern {
         uint16_t tag;
         uint8_t reserved[6];
         uint64_t val;
  } VirtIOBalloonStatModern;
  
  enum virtio_balloon_free_page_report_status {
      FREE_PAGE_REPORT_S_STOP = 0,
      FREE_PAGE_REPORT_S_REQUESTED = 1,
      FREE_PAGE_REPORT_S_START = 2,
      FREE_PAGE_REPORT_S_DONE = 3,
  };
  
  typedef struct VirtIOBalloon {
      VirtIODevice parent_obj;
      VirtQueue *ivq, *dvq, *svq, *free_page_vq;
      uint32_t free_page_report_status;
      uint32_t num_pages;
      uint32_t actual;
      uint32_t free_page_report_cmd_id;
      uint64_t stats[VIRTIO_BALLOON_S_NR];
      VirtQueueElement *stats_vq_elem;
      size_t stats_vq_offset;
      QEMUTimer *stats_timer;
      IOThread *iothread;
      QEMUBH *free_page_bh;
      /*
       * Lock to synchronize threads to access the free page reporting related
       * fields (e.g. free_page_report_status).
       */
      QemuMutex free_page_lock;
      QemuCond  free_page_cond;
      /*
       * Set to block iothread to continue reading free page hints as the VM is
       * stopped.
       */
      bool block_iothread;
      NotifierWithReturn free_page_report_notify;
      int64_t stats_last_update;
      int64_t stats_poll_interval;
      uint32_t host_features;
  
      bool qemu_4_0_config_size;
  } VirtIOBalloon;
  
  #endif
  