Commit 59a88140 authored by Steffen Eiden's avatar Steffen Eiden Committed by Janosch Frank
Browse files

s390/uv: UV feature check utility 



Introduces a function to check the existence of an UV feature.
Refactor feature bit checks to use the new function.

Signed-off-by: default avatarSteffen Eiden <seiden@linux.ibm.com>
Reviewed-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Signed-off-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: default avatarMichael Mueller <mimu@linux.ibm.com>
Link: https://lore.kernel.org/r/20230815151415.379760-3-seiden@linux.ibm.com
Message-Id: <20230815151415.379760-3-seiden@linux.ibm.com>
parent b1e42861

arch/s390/include/asm/uv.h

+7 −0
Original line number Diff line number Diff line
@@ -397,6 +397,13 @@ struct uv_info { 


extern struct uv_info uv_info;



static inline bool uv_has_feature(u8 feature_bit)

{

	if (feature_bit >= sizeof(uv_info.uv_feature_indications) * 8)

		return false;

	return test_bit_inv(feature_bit, &uv_info.uv_feature_indications);

}



#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST

extern int prot_virt_guest;

arch/s390/kernel/uv.c

+1 −1
Original line number Diff line number Diff line
@@ -258,7 +258,7 @@ static bool should_export_before_import(struct uv_cb_header *uvcb, struct mm_str 
	 * shared page from a different protected VM will automatically also

	 * transfer its ownership.

	 */

	if (test_bit_inv(BIT_UV_FEAT_MISC, &uv_info.uv_feature_indications))

	if (uv_has_feature(BIT_UV_FEAT_MISC))

		return false;

	if (uvcb->cmd == UVC_CMD_UNPIN_PAGE_SHARED)

		return false;

arch/s390/kvm/kvm-s390.c

+1 −1
Original line number Diff line number Diff line
@@ -2406,7 +2406,7 @@ static int kvm_s390_cpus_to_pv(struct kvm *kvm, u16 *rc, u16 *rrc) 
	struct kvm_vcpu *vcpu;



	/* Disable the GISA if the ultravisor does not support AIV. */

	if (!test_bit_inv(BIT_UV_FEAT_AIV, &uv_info.uv_feature_indications))

	if (!uv_has_feature(BIT_UV_FEAT_AIV))

		kvm_s390_gisa_disable(kvm);



	kvm_for_each_vcpu(i, vcpu, kvm) {

arch/s390/mm/fault.c

+1 −1
Original line number Diff line number Diff line
@@ -825,7 +825,7 @@ void do_secure_storage_access(struct pt_regs *regs) 
	 * reliable without the misc UV feature so we need to check

	 * for that as well.

	 */

	if (test_bit_inv(BIT_UV_FEAT_MISC, &uv_info.uv_feature_indications) &&

	if (uv_has_feature(BIT_UV_FEAT_MISC) &&

	    !test_bit_inv(61, &regs->int_parm_long)) {

		/*

		 * When this happens, userspace did something that it