return 0;
}
-static int cmp_memslot(const void *slot1, const void *slot2)
-{
- struct kvm_memory_slot *s1, *s2;
-
- s1 = (struct kvm_memory_slot *)slot1;
- s2 = (struct kvm_memory_slot *)slot2;
-
- if (s1->npages < s2->npages)
- return 1;
- if (s1->npages > s2->npages)
- return -1;
-
- return 0;
-}
-
/*
- * Sort the memslots base on its size, so the larger slots
- * will get better fit.
+ * Insert memslot and re-sort memslots based on their size,
+ * so the larger slots will get better fit. Sorting algorithm
+ * takes advantage of having initially sorted array and
+ * known changed memslot position.
*/
-static void sort_memslots(struct kvm_memslots *slots)
-{
- int i;
-
- sort(slots->memslots, KVM_MEM_SLOTS_NUM,
- sizeof(struct kvm_memory_slot), cmp_memslot, NULL);
-
- for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
- slots->id_to_index[slots->memslots[i].id] = i;
-}
-
static void update_memslots(struct kvm_memslots *slots,
struct kvm_memory_slot *new)
{
- if (new) {
- int id = new->id;
- struct kvm_memory_slot *old = id_to_memslot(slots, id);
- unsigned long npages = old->npages;
-
- *old = *new;
- if (new->npages != npages)
- sort_memslots(slots);
+ int id = new->id;
+ int i = slots->id_to_index[id];
+ struct kvm_memory_slot *mslots = slots->memslots;
+
+ WARN_ON(mslots[i].id != id);
+ if (new->npages != mslots[i].npages) {
+ if (new->npages < mslots[i].npages) {
+ while (i < KVM_MEM_SLOTS_NUM - 1 &&
+ new->npages < mslots[i + 1].npages) {
+ mslots[i] = mslots[i + 1];
+ slots->id_to_index[mslots[i].id] = i;
+ i++;
+ }
+ } else {
+ while (i > 0 &&
+ new->npages > mslots[i - 1].npages) {
+ mslots[i] = mslots[i - 1];
+ slots->id_to_index[mslots[i].id] = i;
+ i--;
+ }
+ }
}
+
+ mslots[i] = *new;
+ slots->id_to_index[mslots[i].id] = i;
}
static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
}
static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
- struct kvm_memslots *slots, struct kvm_memory_slot *new)
+ struct kvm_memslots *slots)
{
struct kvm_memslots *old_memslots = kvm->memslots;
WARN_ON(old_memslots->generation & 1);
slots->generation = old_memslots->generation + 1;
- update_memslots(slots, new);
rcu_assign_pointer(kvm->memslots, slots);
synchronize_srcu_expedited(&kvm->srcu);
*
* Discontiguous memory is allowed, mostly for framebuffers.
*
- * Must be called holding mmap_sem for write.
+ * Must be called holding kvm->slots_lock for write.
*/
int __kvm_set_memory_region(struct kvm *kvm,
struct kvm_userspace_memory_region *mem)
goto out_free;
}
+ slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
+ GFP_KERNEL);
+ if (!slots)
+ goto out_free;
+
if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
- slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
- GFP_KERNEL);
- if (!slots)
- goto out_free;
slot = id_to_memslot(slots, mem->slot);
slot->flags |= KVM_MEMSLOT_INVALID;
- old_memslots = install_new_memslots(kvm, slots, NULL);
+ old_memslots = install_new_memslots(kvm, slots);
/* slot was deleted or moved, clear iommu mapping */
kvm_iommu_unmap_pages(kvm, &old);
* - kvm_is_visible_gfn (mmu_check_roots)
*/
kvm_arch_flush_shadow_memslot(kvm, slot);
+
+ /*
+ * We can re-use the old_memslots from above, the only difference
+ * from the currently installed memslots is the invalid flag. This
+ * will get overwritten by update_memslots anyway.
+ */
slots = old_memslots;
}
if (r)
goto out_slots;
- r = -ENOMEM;
- /*
- * We can re-use the old_memslots from above, the only difference
- * from the currently installed memslots is the invalid flag. This
- * will get overwritten by update_memslots anyway.
- */
- if (!slots) {
- slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
- GFP_KERNEL);
- if (!slots)
- goto out_free;
- }
-
/* actual memory is freed via old in kvm_free_physmem_slot below */
if (change == KVM_MR_DELETE) {
new.dirty_bitmap = NULL;
memset(&new.arch, 0, sizeof(new.arch));
}
- old_memslots = install_new_memslots(kvm, slots, &new);
+ update_memslots(slots, &new);
+ old_memslots = install_new_memslots(kvm, slots);
kvm_arch_commit_memory_region(kvm, mem, &old, change);