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Diffstat (limited to 'virt/kvm/kvm_main.c')
-rw-r--r--virt/kvm/kvm_main.c101
1 files changed, 55 insertions, 46 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 76c92a7249c4..278232025129 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -95,8 +95,6 @@ static int hardware_enable_all(void);
static void hardware_disable_all(void);
static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
-static void update_memslots(struct kvm_memslots *slots,
- struct kvm_memory_slot *new, u64 last_generation);
static void kvm_release_pfn_dirty(pfn_t pfn);
static void mark_page_dirty_in_slot(struct kvm *kvm,
@@ -477,6 +475,13 @@ static struct kvm *kvm_create_vm(unsigned long type)
kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
if (!kvm->memslots)
goto out_err_no_srcu;
+
+ /*
+ * Init kvm generation close to the maximum to easily test the
+ * code of handling generation number wrap-around.
+ */
+ kvm->memslots->generation = -150;
+
kvm_init_memslots_id(kvm);
if (init_srcu_struct(&kvm->srcu))
goto out_err_no_srcu;
@@ -688,8 +693,7 @@ static void sort_memslots(struct kvm_memslots *slots)
}
static void update_memslots(struct kvm_memslots *slots,
- struct kvm_memory_slot *new,
- u64 last_generation)
+ struct kvm_memory_slot *new)
{
if (new) {
int id = new->id;
@@ -700,15 +704,13 @@ static void update_memslots(struct kvm_memslots *slots,
if (new->npages != npages)
sort_memslots(slots);
}
-
- slots->generation = last_generation + 1;
}
static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
{
u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
-#ifdef KVM_CAP_READONLY_MEM
+#ifdef __KVM_HAVE_READONLY_MEM
valid_flags |= KVM_MEM_READONLY;
#endif
@@ -723,10 +725,24 @@ static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
{
struct kvm_memslots *old_memslots = kvm->memslots;
- update_memslots(slots, new, kvm->memslots->generation);
+ /*
+ * Set the low bit in the generation, which disables SPTE caching
+ * until the end of synchronize_srcu_expedited.
+ */
+ 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);
+ /*
+ * Increment the new memslot generation a second time. This prevents
+ * vm exits that race with memslot updates from caching a memslot
+ * generation that will (potentially) be valid forever.
+ */
+ slots->generation++;
+
kvm_arch_memslots_updated(kvm);
return old_memslots;
@@ -777,7 +793,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
npages = mem->memory_size >> PAGE_SHIFT;
- r = -EINVAL;
if (npages > KVM_MEM_MAX_NR_PAGES)
goto out;
@@ -791,7 +806,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
new.npages = npages;
new.flags = mem->flags;
- r = -EINVAL;
if (npages) {
if (!old.npages)
change = KVM_MR_CREATE;
@@ -847,7 +861,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
}
if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
- r = -ENOMEM;
slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
GFP_KERNEL);
if (!slots)
@@ -1776,8 +1789,7 @@ static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
bool eligible;
eligible = !vcpu->spin_loop.in_spin_loop ||
- (vcpu->spin_loop.in_spin_loop &&
- vcpu->spin_loop.dy_eligible);
+ vcpu->spin_loop.dy_eligible;
if (vcpu->spin_loop.in_spin_loop)
kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
@@ -2267,6 +2279,29 @@ struct kvm_device *kvm_device_from_filp(struct file *filp)
return filp->private_data;
}
+static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
+#ifdef CONFIG_KVM_MPIC
+ [KVM_DEV_TYPE_FSL_MPIC_20] = &kvm_mpic_ops,
+ [KVM_DEV_TYPE_FSL_MPIC_42] = &kvm_mpic_ops,
+#endif
+
+#ifdef CONFIG_KVM_XICS
+ [KVM_DEV_TYPE_XICS] = &kvm_xics_ops,
+#endif
+};
+
+int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type)
+{
+ if (type >= ARRAY_SIZE(kvm_device_ops_table))
+ return -ENOSPC;
+
+ if (kvm_device_ops_table[type] != NULL)
+ return -EEXIST;
+
+ kvm_device_ops_table[type] = ops;
+ return 0;
+}
+
static int kvm_ioctl_create_device(struct kvm *kvm,
struct kvm_create_device *cd)
{
@@ -2275,36 +2310,12 @@ static int kvm_ioctl_create_device(struct kvm *kvm,
bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
int ret;
- switch (cd->type) {
-#ifdef CONFIG_KVM_MPIC
- case KVM_DEV_TYPE_FSL_MPIC_20:
- case KVM_DEV_TYPE_FSL_MPIC_42:
- ops = &kvm_mpic_ops;
- break;
-#endif
-#ifdef CONFIG_KVM_XICS
- case KVM_DEV_TYPE_XICS:
- ops = &kvm_xics_ops;
- break;
-#endif
-#ifdef CONFIG_KVM_VFIO
- case KVM_DEV_TYPE_VFIO:
- ops = &kvm_vfio_ops;
- break;
-#endif
-#ifdef CONFIG_KVM_ARM_VGIC
- case KVM_DEV_TYPE_ARM_VGIC_V2:
- ops = &kvm_arm_vgic_v2_ops;
- break;
-#endif
-#ifdef CONFIG_S390
- case KVM_DEV_TYPE_FLIC:
- ops = &kvm_flic_ops;
- break;
-#endif
- default:
+ if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
+ return -ENODEV;
+
+ ops = kvm_device_ops_table[cd->type];
+ if (ops == NULL)
return -ENODEV;
- }
if (test)
return 0;
@@ -2619,7 +2630,6 @@ static long kvm_dev_ioctl(struct file *filp,
switch (ioctl) {
case KVM_GET_API_VERSION:
- r = -EINVAL;
if (arg)
goto out;
r = KVM_API_VERSION;
@@ -2631,7 +2641,6 @@ static long kvm_dev_ioctl(struct file *filp,
r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
break;
case KVM_GET_VCPU_MMAP_SIZE:
- r = -EINVAL;
if (arg)
goto out;
r = PAGE_SIZE; /* struct kvm_run */
@@ -2676,7 +2685,7 @@ static void hardware_enable_nolock(void *junk)
cpumask_set_cpu(cpu, cpus_hardware_enabled);
- r = kvm_arch_hardware_enable(NULL);
+ r = kvm_arch_hardware_enable();
if (r) {
cpumask_clear_cpu(cpu, cpus_hardware_enabled);
@@ -2701,7 +2710,7 @@ static void hardware_disable_nolock(void *junk)
if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
return;
cpumask_clear_cpu(cpu, cpus_hardware_enabled);
- kvm_arch_hardware_disable(NULL);
+ kvm_arch_hardware_disable();
}
static void hardware_disable(void)