KVM: Remove user_alloc from struct kvm_memory_slot
This field was needed to differentiate memory slots created by the new
API, KVM_SET_USER_MEMORY_REGION, from those by the old equivalent,
KVM_SET_MEMORY_REGION, whose support was dropped long before:
commit b74a07beed0e64bfba413dcb70dd6749c57f43dc
KVM: Remove kernel-allocated memory regions
Although we also have private memory slots to which KVM allocates
memory with vm_mmap(), !user_alloc slots in other words, the slot id
should be enough for differentiating them.
Note: corresponding function parameters will be removed later.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 373e17a..3c5bb6f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6897,33 +6897,28 @@
bool user_alloc)
{
int npages = memslot->npages;
- int map_flags = MAP_PRIVATE | MAP_ANONYMOUS;
- /* Prevent internal slot pages from being moved by fork()/COW. */
- if (memslot->id >= KVM_USER_MEM_SLOTS)
- map_flags = MAP_SHARED | MAP_ANONYMOUS;
-
- /*To keep backward compatibility with older userspace,
- *x86 needs to handle !user_alloc case.
+ /*
+ * Only private memory slots need to be mapped here since
+ * KVM_SET_MEMORY_REGION ioctl is no longer supported.
*/
- if (!user_alloc) {
- if (npages && !old.npages) {
- unsigned long userspace_addr;
+ if ((memslot->id >= KVM_USER_MEM_SLOTS) && npages && !old.npages) {
+ unsigned long userspace_addr;
- userspace_addr = vm_mmap(NULL, 0,
- npages * PAGE_SIZE,
- PROT_READ | PROT_WRITE,
- map_flags,
- 0);
+ /*
+ * MAP_SHARED to prevent internal slot pages from being moved
+ * by fork()/COW.
+ */
+ userspace_addr = vm_mmap(NULL, 0, npages * PAGE_SIZE,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_ANONYMOUS, 0);
- if (IS_ERR((void *)userspace_addr))
- return PTR_ERR((void *)userspace_addr);
+ if (IS_ERR((void *)userspace_addr))
+ return PTR_ERR((void *)userspace_addr);
- memslot->userspace_addr = userspace_addr;
- }
+ memslot->userspace_addr = userspace_addr;
}
-
return 0;
}
@@ -6935,7 +6930,7 @@
int nr_mmu_pages = 0, npages = mem->memory_size >> PAGE_SHIFT;
- if (!user_alloc && !old.user_alloc && old.npages && !npages) {
+ if ((mem->slot >= KVM_USER_MEM_SLOTS) && old.npages && !npages) {
int ret;
ret = vm_munmap(old.userspace_addr,