Staging
v0.5.2
v0.5.2
https://github.com/torvalds/linux
Tip revision: 8a749fd1a8720d4619c91c8b6e7528c0a355c0aa authored by Linus Torvalds on 01 October 2023, 21:15:13 UTC
Linux 6.6-rc4
Linux 6.6-rc4
Tip revision: 8a749fd
kvm_dirty_ring.h
#ifndef KVM_DIRTY_RING_H
#define KVM_DIRTY_RING_H
#include <linux/kvm.h>
/**
* kvm_dirty_ring: KVM internal dirty ring structure
*
* @dirty_index: free running counter that points to the next slot in
* dirty_ring->dirty_gfns, where a new dirty page should go
* @reset_index: free running counter that points to the next dirty page
* in dirty_ring->dirty_gfns for which dirty trap needs to
* be reenabled
* @size: size of the compact list, dirty_ring->dirty_gfns
* @soft_limit: when the number of dirty pages in the list reaches this
* limit, vcpu that owns this ring should exit to userspace
* to allow userspace to harvest all the dirty pages
* @dirty_gfns: the array to keep the dirty gfns
* @index: index of this dirty ring
*/
struct kvm_dirty_ring {
u32 dirty_index;
u32 reset_index;
u32 size;
u32 soft_limit;
struct kvm_dirty_gfn *dirty_gfns;
int index;
};
#ifndef CONFIG_HAVE_KVM_DIRTY_RING
/*
* If CONFIG_HAVE_HVM_DIRTY_RING not defined, kvm_dirty_ring.o should
* not be included as well, so define these nop functions for the arch.
*/
static inline u32 kvm_dirty_ring_get_rsvd_entries(void)
{
return 0;
}
static inline bool kvm_use_dirty_bitmap(struct kvm *kvm)
{
return true;
}
static inline int kvm_dirty_ring_alloc(struct kvm_dirty_ring *ring,
int index, u32 size)
{
return 0;
}
static inline int kvm_dirty_ring_reset(struct kvm *kvm,
struct kvm_dirty_ring *ring)
{
return 0;
}
static inline void kvm_dirty_ring_push(struct kvm_vcpu *vcpu,
u32 slot, u64 offset)
{
}
static inline struct page *kvm_dirty_ring_get_page(struct kvm_dirty_ring *ring,
u32 offset)
{
return NULL;
}
static inline void kvm_dirty_ring_free(struct kvm_dirty_ring *ring)
{
}
#else /* CONFIG_HAVE_KVM_DIRTY_RING */
int kvm_cpu_dirty_log_size(void);
bool kvm_use_dirty_bitmap(struct kvm *kvm);
bool kvm_arch_allow_write_without_running_vcpu(struct kvm *kvm);
u32 kvm_dirty_ring_get_rsvd_entries(void);
int kvm_dirty_ring_alloc(struct kvm_dirty_ring *ring, int index, u32 size);
/*
* called with kvm->slots_lock held, returns the number of
* processed pages.
*/
int kvm_dirty_ring_reset(struct kvm *kvm, struct kvm_dirty_ring *ring);
/*
* returns =0: successfully pushed
* <0: unable to push, need to wait
*/
void kvm_dirty_ring_push(struct kvm_vcpu *vcpu, u32 slot, u64 offset);
bool kvm_dirty_ring_check_request(struct kvm_vcpu *vcpu);
/* for use in vm_operations_struct */
struct page *kvm_dirty_ring_get_page(struct kvm_dirty_ring *ring, u32 offset);
void kvm_dirty_ring_free(struct kvm_dirty_ring *ring);
#endif /* CONFIG_HAVE_KVM_DIRTY_RING */
#endif /* KVM_DIRTY_RING_H */