Commit 48547fe7 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: SVM: Add a helper to convert a SME-aware PA back to a struct page 

Add __sme_pa_to_page() to pair with __sme_page_pa() and use it to replace
open coded equivalents, including for "iopm_base", which previously
avoided having to do __sme_clr() by storing the raw PA in the global
variable.

Opportunistically convert __sme_page_pa() to a helper to provide type
safety.

No functional change intended.

Link: https://lore.kernel.org/r/20240802204511.352017-2-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent c501062b

arch/x86/kvm/svm/svm.c

+4 −5
Original line number Diff line number Diff line
@@ -1124,8 +1124,7 @@ static void svm_hardware_unsetup(void) 
	for_each_possible_cpu(cpu)

		svm_cpu_uninit(cpu);



	__free_pages(pfn_to_page(iopm_base >> PAGE_SHIFT),

	get_order(IOPM_SIZE));

	__free_pages(__sme_pa_to_page(iopm_base), get_order(IOPM_SIZE));

	iopm_base = 0;

}
@@ -1301,7 +1300,7 @@ static void init_vmcb(struct kvm_vcpu *vcpu) 
	if (!kvm_hlt_in_guest(vcpu->kvm))

		svm_set_intercept(svm, INTERCEPT_HLT);



	control->iopm_base_pa = __sme_set(iopm_base);

	control->iopm_base_pa = iopm_base;

	control->msrpm_base_pa = __sme_set(__pa(svm->msrpm));

	control->int_ctl = V_INTR_MASKING_MASK;
@@ -1503,7 +1502,7 @@ static void svm_vcpu_free(struct kvm_vcpu *vcpu) 


	sev_free_vcpu(vcpu);



	__free_page(pfn_to_page(__sme_clr(svm->vmcb01.pa) >> PAGE_SHIFT));

	__free_page(__sme_pa_to_page(svm->vmcb01.pa));

	__free_pages(virt_to_page(svm->msrpm), get_order(MSRPM_SIZE));

}
@@ -5251,7 +5250,7 @@ static __init int svm_hardware_setup(void) 


	iopm_va = page_address(iopm_pages);

	memset(iopm_va, 0xff, PAGE_SIZE * (1 << order));

	iopm_base = page_to_pfn(iopm_pages) << PAGE_SHIFT;

	iopm_base = __sme_page_pa(iopm_pages);



	init_msrpm_offsets();

arch/x86/kvm/svm/svm.h

+15 −1
Original line number Diff line number Diff line
@@ -25,7 +25,21 @@ 
#include "cpuid.h"

#include "kvm_cache_regs.h"



#define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT)

/*

 * Helpers to convert to/from physical addresses for pages whose address is

 * consumed directly by hardware.  Even though it's a physical address, SVM

 * often restricts the address to the natural width, hence 'unsigned long'

 * instead of 'hpa_t'.

 */

static inline unsigned long __sme_page_pa(struct page *page)

{

	return __sme_set(page_to_pfn(page) << PAGE_SHIFT);

}



static inline struct page *__sme_pa_to_page(unsigned long pa)

{

	return pfn_to_page(__sme_clr(pa) >> PAGE_SHIFT);

}



#define	IOPM_SIZE PAGE_SIZE * 3

#define	MSRPM_SIZE PAGE_SIZE * 2