KVM: x86: map/unmap private slots in __x86_set_memory_region

[karo-tx-linux.git] / arch / x86 / kvm / x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7bf8096f013da2271c867f4af4bad7cd2bd3fc45..3ac33f86c8737c7f32c85885626a0b532ea6cfe6 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7477,23 +7477,53 @@ void kvm_arch_sync_events(struct kvm *kvm)
 int __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size)
 {
        int i, r;
+       u64 hva;
+       struct kvm_memslots *slots = kvm_memslots(kvm);
+       struct kvm_memory_slot *slot, old;
 
        /* Called with kvm->slots_lock held.  */
        if (WARN_ON(id >= KVM_MEM_SLOTS_NUM))
                return -EINVAL;
 
+       slot = id_to_memslot(slots, id);
+       if (size) {
+               if (WARN_ON(slot->npages))
+                       return -EEXIST;
+
+               /*
+                * MAP_SHARED to prevent internal slot pages from being moved
+                * by fork()/COW.
+                */
+               hva = vm_mmap(NULL, 0, size, PROT_READ | PROT_WRITE,
+                             MAP_SHARED | MAP_ANONYMOUS, 0);
+               if (IS_ERR((void *)hva))
+                       return PTR_ERR((void *)hva);
+       } else {
+               if (!slot->npages)
+                       return 0;
+
+               hva = 0;
+       }
+
+       old = *slot;
        for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
                struct kvm_userspace_memory_region m;
 
                m.slot = id | (i << 16);
                m.flags = 0;
                m.guest_phys_addr = gpa;
+               m.userspace_addr = hva;
                m.memory_size = size;
                r = __kvm_set_memory_region(kvm, &m);
                if (r < 0)
                        return r;
        }
 
+       if (!size) {
+               r = vm_munmap(old.userspace_addr, old.npages * PAGE_SIZE);
+               WARN_ON(r < 0);
+       }
+
        return 0;
 }
 EXPORT_SYMBOL_GPL(__x86_set_memory_region);
@@ -7623,27 +7653,6 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
                                const struct kvm_userspace_memory_region *mem,
                                enum kvm_mr_change change)
 {
-       /*
-        * Only private memory slots need to be mapped here since
-        * KVM_SET_MEMORY_REGION ioctl is no longer supported.
-        */
-       if ((memslot->id >= KVM_USER_MEM_SLOTS) && (change == KVM_MR_CREATE)) {
-               unsigned long userspace_addr;
-
-               /*
-                * MAP_SHARED to prevent internal slot pages from being moved
-                * by fork()/COW.
-                */
-               userspace_addr = vm_mmap(NULL, 0, memslot->npages * PAGE_SIZE,
-                                        PROT_READ | PROT_WRITE,
-                                        MAP_SHARED | MAP_ANONYMOUS, 0);
-
-               if (IS_ERR((void *)userspace_addr))
-                       return PTR_ERR((void *)userspace_addr);
-
-               memslot->userspace_addr = userspace_addr;
-       }
-
        return 0;
 }
 
@@ -7705,17 +7714,6 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
 {
        int nr_mmu_pages = 0;
 
-       if (change == KVM_MR_DELETE && old->id >= KVM_USER_MEM_SLOTS) {
-               int ret;
-
-               ret = vm_munmap(old->userspace_addr,
-                               old->npages * PAGE_SIZE);
-               if (ret < 0)
-                       printk(KERN_WARNING
-                              "kvm_vm_ioctl_set_memory_region: "
-                              "failed to munmap memory\n");
-       }
-
        if (!kvm->arch.n_requested_mmu_pages)
                nr_mmu_pages = kvm_mmu_calculate_mmu_pages(kvm);