Commit 0f8a4de3 authored Aug 26, 2014 by Christoffer Dall Committed by Paolo Bonzini Aug 29, 2014

KVM: Unconditionally export KVM_CAP_READONLY_MEM



The idea between capabilities and the KVM_CHECK_EXTENSION ioctl is that
userspace can, at run-time, determine if a feature is supported or not.
This allows KVM to being supporting a new feature with a new kernel
version without any need to update user space.  Unfortunately, since the
definition of KVM_CAP_READONLY_MEM was guarded by #ifdef
__KVM_HAVE_READONLY_MEM, such discovery still required a user space
update.

Therefore, unconditionally export KVM_CAP_READONLY_MEM and change the
in-kernel conditional to rely on __KVM_HAVE_READONLY_MEM.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent dc77d344

include/uapi/linux/kvm.h

+0 −2

Original line number	Diff line number	Diff line
		@@ -738,9 +738,7 @@ struct kvm_ppc_smmu_info {
		#define KVM_CAP_PPC_GET_SMMU_INFO 78
		#define KVM_CAP_S390_COW 79
		#define KVM_CAP_PPC_ALLOC_HTAB 80
		#ifdef __KVM_HAVE_READONLY_MEM
		#define KVM_CAP_READONLY_MEM 81
		#endif
		#define KVM_CAP_IRQFD_RESAMPLE 82
		#define KVM_CAP_PPC_BOOKE_WATCHDOG 83
		#define KVM_CAP_PPC_HTAB_FD 84

virt/kvm/kvm_main.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -708,7 +708,7 @@ 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