include/xen/balloon.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /******************************************************************************
   3  * Xen balloon functionality
   4  */
   5
   6 #define RETRY_UNLIMITED 0
   7
   8 struct balloon_stats {
   9         /* We aim for 'current allocation' == 'target allocation'. */
  10         unsigned long current_pages;
  11         unsigned long target_pages;
  12         unsigned long target_unpopulated;
  13         /* Number of pages in high- and low-memory balloons. */
  14         unsigned long balloon_low;
  15         unsigned long balloon_high;
  16         unsigned long total_pages;
  17         unsigned long schedule_delay;
  18         unsigned long max_schedule_delay;
  19         unsigned long retry_count;
  20         unsigned long max_retry_count;
  21 };
  22
  23 extern struct balloon_stats balloon_stats;
  24
  25 void balloon_set_new_target(unsigned long target);
  26
  27 int alloc_xenballooned_pages(int nr_pages, struct page **pages);
  28 void free_xenballooned_pages(int nr_pages, struct page **pages);
  29
  30 struct device;
  31 #ifdef CONFIG_XEN_SELFBALLOONING
  32 extern int register_xen_selfballooning(struct device *dev);
  33 #else
  34 static inline int register_xen_selfballooning(struct device *dev)
  35 {
  36         return -ENOSYS;
  37 }
  38 #endif
  39
  40 #ifdef CONFIG_XEN_BALLOON
  41 void xen_balloon_init(void);
  42 #else
  43 static inline void xen_balloon_init(void)
  44 {
  45 }
  46 #endif
  47
  48 #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
  49 struct resource;
  50 void arch_xen_balloon_init(struct resource *hostmem_resource);
  51 #endif