1 #ifndef KVM_DIRTY_RING_H 2 #define KVM_DIRTY_RING_H 3 4 #include <linux/kvm.h> 5 6 /** 7 * kvm_dirty_ring: KVM internal dirty ring structure 8 * 9 * @dirty_index: free running counter that points to the next slot in 10 * dirty_ring->dirty_gfns, where a new dirty page should go 11 * @reset_index: free running counter that points to the next dirty page 12 * in dirty_ring->dirty_gfns for which dirty trap needs to 13 * be reenabled 14 * @size: size of the compact list, dirty_ring->dirty_gfns 15 * @soft_limit: when the number of dirty pages in the list reaches this 16 * limit, vcpu that owns this ring should exit to userspace 17 * to allow userspace to harvest all the dirty pages 18 * @dirty_gfns: the array to keep the dirty gfns 19 * @index: index of this dirty ring 20 */ 21 struct kvm_dirty_ring { 22 u32 dirty_index; 23 u32 reset_index; 24 u32 size; 25 u32 soft_limit; 26 struct kvm_dirty_gfn *dirty_gfns; 27 int index; 28 }; 29 30 #ifndef CONFIG_HAVE_KVM_DIRTY_RING 31 /* 32 * If CONFIG_HAVE_HVM_DIRTY_RING not defined, kvm_dirty_ring.o should 33 * not be included as well, so define these nop functions for the arch. 34 */ 35 static inline u32 kvm_dirty_ring_get_rsvd_entries(void) 36 { 37 return 0; 38 } 39 40 static inline int kvm_dirty_ring_alloc(struct kvm_dirty_ring *ring, 41 int index, u32 size) 42 { 43 return 0; 44 } 45 46 static inline int kvm_dirty_ring_reset(struct kvm *kvm, 47 struct kvm_dirty_ring *ring) 48 { 49 return 0; 50 } 51 52 static inline void kvm_dirty_ring_push(struct kvm_dirty_ring *ring, 53 u32 slot, u64 offset) 54 { 55 } 56 57 static inline struct page *kvm_dirty_ring_get_page(struct kvm_dirty_ring *ring, 58 u32 offset) 59 { 60 return NULL; 61 } 62 63 static inline void kvm_dirty_ring_free(struct kvm_dirty_ring *ring) 64 { 65 } 66 67 static inline bool kvm_dirty_ring_soft_full(struct kvm_dirty_ring *ring) 68 { 69 return true; 70 } 71 72 #else /* CONFIG_HAVE_KVM_DIRTY_RING */ 73 74 u32 kvm_dirty_ring_get_rsvd_entries(void); 75 int kvm_dirty_ring_alloc(struct kvm_dirty_ring *ring, int index, u32 size); 76 77 /* 78 * called with kvm->slots_lock held, returns the number of 79 * processed pages. 80 */ 81 int kvm_dirty_ring_reset(struct kvm *kvm, struct kvm_dirty_ring *ring); 82 83 /* 84 * returns =0: successfully pushed 85 * <0: unable to push, need to wait 86 */ 87 void kvm_dirty_ring_push(struct kvm_dirty_ring *ring, u32 slot, u64 offset); 88 89 /* for use in vm_operations_struct */ 90 struct page *kvm_dirty_ring_get_page(struct kvm_dirty_ring *ring, u32 offset); 91 92 void kvm_dirty_ring_free(struct kvm_dirty_ring *ring); 93 bool kvm_dirty_ring_soft_full(struct kvm_dirty_ring *ring); 94 95 #endif /* CONFIG_HAVE_KVM_DIRTY_RING */ 96 97 #endif /* KVM_DIRTY_RING_H */ 98