kvm: Consolidate must-have capability checks
Instead of splattering the code with #ifdefs and runtime checks for
capabilities we cannot work without anyway, provide central test
infrastructure for verifying their availability both at build and
runtime.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/kvm-all.c b/kvm-all.c
index 8053f92..3a1f63b 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -63,9 +63,7 @@
int fd;
int vmfd;
int coalesced_mmio;
-#ifdef KVM_CAP_COALESCED_MMIO
struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
-#endif
int broken_set_mem_region;
int migration_log;
int vcpu_events;
@@ -82,6 +80,12 @@
static KVMState *kvm_state;
+static const KVMCapabilityInfo kvm_required_capabilites[] = {
+ KVM_CAP_INFO(USER_MEMORY),
+ KVM_CAP_INFO(DESTROY_MEMORY_REGION_WORKS),
+ KVM_CAP_LAST_INFO
+};
+
static KVMSlot *kvm_alloc_slot(KVMState *s)
{
int i;
@@ -227,12 +231,10 @@
goto err;
}
-#ifdef KVM_CAP_COALESCED_MMIO
if (s->coalesced_mmio && !s->coalesced_mmio_ring) {
s->coalesced_mmio_ring =
(void *)env->kvm_run + s->coalesced_mmio * PAGE_SIZE;
}
-#endif
ret = kvm_arch_init_vcpu(env);
if (ret == 0) {
@@ -401,7 +403,6 @@
int kvm_coalesce_mmio_region(target_phys_addr_t start, ram_addr_t size)
{
int ret = -ENOSYS;
-#ifdef KVM_CAP_COALESCED_MMIO
KVMState *s = kvm_state;
if (s->coalesced_mmio) {
@@ -412,7 +413,6 @@
ret = kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
}
-#endif
return ret;
}
@@ -420,7 +420,6 @@
int kvm_uncoalesce_mmio_region(target_phys_addr_t start, ram_addr_t size)
{
int ret = -ENOSYS;
-#ifdef KVM_CAP_COALESCED_MMIO
KVMState *s = kvm_state;
if (s->coalesced_mmio) {
@@ -431,7 +430,6 @@
ret = kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
}
-#endif
return ret;
}
@@ -481,6 +479,18 @@
#endif
}
+static const KVMCapabilityInfo *
+kvm_check_extension_list(KVMState *s, const KVMCapabilityInfo *list)
+{
+ while (list->name) {
+ if (!kvm_check_extension(s, list->value)) {
+ return list;
+ }
+ list++;
+ }
+ return NULL;
+}
+
static void kvm_set_phys_mem(target_phys_addr_t start_addr, ram_addr_t size,
ram_addr_t phys_offset)
{
@@ -642,6 +652,7 @@
"Please upgrade to at least kernel 2.6.29 or recent kvm-kmod\n"
"(see http://sourceforge.net/projects/kvm).\n";
KVMState *s;
+ const KVMCapabilityInfo *missing_cap;
int ret;
int i;
@@ -685,35 +696,19 @@
goto err;
}
- /* initially, KVM allocated its own memory and we had to jump through
- * hooks to make phys_ram_base point to this. Modern versions of KVM
- * just use a user allocated buffer so we can use regular pages
- * unmodified. Make sure we have a sufficiently modern version of KVM.
- */
- if (!kvm_check_extension(s, KVM_CAP_USER_MEMORY)) {
+ missing_cap = kvm_check_extension_list(s, kvm_required_capabilites);
+ if (!missing_cap) {
+ missing_cap =
+ kvm_check_extension_list(s, kvm_arch_required_capabilities);
+ }
+ if (missing_cap) {
ret = -EINVAL;
- fprintf(stderr, "kvm does not support KVM_CAP_USER_MEMORY\n%s",
- upgrade_note);
+ fprintf(stderr, "kvm does not support %s\n%s",
+ missing_cap->name, upgrade_note);
goto err;
}
- /* There was a nasty bug in < kvm-80 that prevents memory slots from being
- * destroyed properly. Since we rely on this capability, refuse to work
- * with any kernel without this capability. */
- if (!kvm_check_extension(s, KVM_CAP_DESTROY_MEMORY_REGION_WORKS)) {
- ret = -EINVAL;
-
- fprintf(stderr,
- "KVM kernel module broken (DESTROY_MEMORY_REGION).\n%s",
- upgrade_note);
- goto err;
- }
-
- s->coalesced_mmio = 0;
-#ifdef KVM_CAP_COALESCED_MMIO
s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
- s->coalesced_mmio_ring = NULL;
-#endif
s->broken_set_mem_region = 1;
#ifdef KVM_CAP_JOIN_MEMORY_REGIONS_WORKS
@@ -845,7 +840,6 @@
void kvm_flush_coalesced_mmio_buffer(void)
{
-#ifdef KVM_CAP_COALESCED_MMIO
KVMState *s = kvm_state;
if (s->coalesced_mmio_ring) {
struct kvm_coalesced_mmio_ring *ring = s->coalesced_mmio_ring;
@@ -859,7 +853,6 @@
ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
}
}
-#endif
}
static void do_kvm_cpu_synchronize_state(void *_env)
@@ -1059,13 +1052,7 @@
int kvm_has_sync_mmu(void)
{
-#ifdef KVM_CAP_SYNC_MMU
- KVMState *s = kvm_state;
-
- return kvm_check_extension(s, KVM_CAP_SYNC_MMU);
-#else
- return 0;
-#endif
+ return kvm_check_extension(kvm_state, KVM_CAP_SYNC_MMU);
}
int kvm_has_vcpu_events(void)