diff --git a/kvm-all.c b/kvm-all.c index 36659a95e8..0ac4b1e1e0 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -320,6 +320,18 @@ int kvm_uncoalesce_mmio_region(target_phys_addr_t start, ram_addr_t size) return ret; } +int kvm_check_extension(KVMState *s, unsigned int extension) +{ + int ret; + + ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, extension); + if (ret < 0) { + ret = 0; + } + + return ret; +} + int kvm_init(int smp_cpus) { KVMState *s; @@ -368,10 +380,8 @@ int kvm_init(int smp_cpus) * just use a user allocated buffer so we can use regular pages * unmodified. Make sure we have a sufficiently modern version of KVM. */ - ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_USER_MEMORY); - if (ret <= 0) { - if (ret == 0) - ret = -EINVAL; + if (!kvm_check_extension(s, KVM_CAP_USER_MEMORY)) { + ret = -EINVAL; fprintf(stderr, "kvm does not support KVM_CAP_USER_MEMORY\n"); goto err; } @@ -379,11 +389,8 @@ int kvm_init(int smp_cpus) /* 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. */ - ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, - KVM_CAP_DESTROY_MEMORY_REGION_WORKS); - if (ret <= 0) { - if (ret == 0) - ret = -EINVAL; + if (!kvm_check_extension(s, KVM_CAP_DESTROY_MEMORY_REGION_WORKS)) { + ret = -EINVAL; fprintf(stderr, "KVM kernel module broken (DESTROY_MEMORY_REGION)\n" @@ -391,11 +398,10 @@ int kvm_init(int smp_cpus) goto err; } - s->coalesced_mmio = 0; #ifdef KVM_CAP_COALESCED_MMIO - ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_COALESCED_MMIO); - if (ret > 0) - s->coalesced_mmio = ret; + s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO); +#else + s->coalesced_mmio = 0; #endif ret = kvm_arch_init(s, smp_cpus); @@ -766,11 +772,10 @@ int kvm_has_sync_mmu(void) #ifdef KVM_CAP_SYNC_MMU KVMState *s = kvm_state; - if (kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_SYNC_MMU) > 0) - return 1; -#endif - + return kvm_check_extension(s, KVM_CAP_SYNC_MMU); +#else return 0; +#endif } void kvm_setup_guest_memory(void *start, size_t size) diff --git a/kvm.h b/kvm.h index 0ea24266be..25b120cba6 100644 --- a/kvm.h +++ b/kvm.h @@ -118,6 +118,8 @@ void kvm_arch_remove_all_hw_breakpoints(void); void kvm_arch_update_guest_debug(CPUState *env, struct kvm_guest_debug *dbg); +int kvm_check_extension(KVMState *s, unsigned int extension); + /* generic hooks - to be moved/refactored once there are more users */ static inline void cpu_synchronize_state(CPUState *env, int modified)