Commit 7850ac54 authored by Takuya Yoshikawa's avatar Takuya Yoshikawa Committed by Avi Kivity
Browse files

KVM: Count the number of dirty pages for dirty logging 



Needed for the next patch which uses this number to decide how to write
protect a slot.

Signed-off-by: default avatarTakuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 9b9b1492

arch/x86/kvm/x86.c

+3 −6
Original line number Diff line number Diff line
@@ -3466,10 +3466,9 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, 
int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,

				      struct kvm_dirty_log *log)

{

	int r, i;

	int r;

	struct kvm_memory_slot *memslot;

	unsigned long n;

	unsigned long is_dirty = 0;



	mutex_lock(&kvm->slots_lock);
@@ -3484,11 +3483,8 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, 


	n = kvm_dirty_bitmap_bytes(memslot);



	for (i = 0; !is_dirty && i < n/sizeof(long); i++)

		is_dirty = memslot->dirty_bitmap[i];



	/* If nothing is dirty, don't bother messing with page tables. */

	if (is_dirty) {

	if (memslot->nr_dirty_pages) {

		struct kvm_memslots *slots, *old_slots;

		unsigned long *dirty_bitmap;
@@ -3503,6 +3499,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, 
			goto out;

		memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));

		slots->memslots[log->slot].dirty_bitmap = dirty_bitmap;

		slots->memslots[log->slot].nr_dirty_pages = 0;

		slots->generation++;



		old_slots = kvm->memslots;

include/linux/kvm_host.h

+1 −0
Original line number Diff line number Diff line
@@ -181,6 +181,7 @@ struct kvm_memory_slot { 
	unsigned long *rmap;

	unsigned long *dirty_bitmap;

	unsigned long *dirty_bitmap_head;

	unsigned long nr_dirty_pages;

	struct kvm_lpage_info *lpage_info[KVM_NR_PAGE_SIZES - 1];

	unsigned long userspace_addr;

	int user_alloc;

virt/kvm/kvm_main.c

+3 −1
Original line number Diff line number Diff line
@@ -625,6 +625,7 @@ static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot) 
		return -ENOMEM;



	memslot->dirty_bitmap_head = memslot->dirty_bitmap;

	memslot->nr_dirty_pages = 0;

	return 0;

}

#endif /* !CONFIG_S390 */
@@ -1491,7 +1492,8 @@ void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot, 
	if (memslot && memslot->dirty_bitmap) {

		unsigned long rel_gfn = gfn - memslot->base_gfn;



		__set_bit_le(rel_gfn, memslot->dirty_bitmap);

		if (!__test_and_set_bit_le(rel_gfn, memslot->dirty_bitmap))

			memslot->nr_dirty_pages++;

	}

}