Commit 70466381 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: selftests: Consolidate common code for populating ucall struct 



Make ucall() a common helper that populates struct ucall, and only calls
into arch code to make the actually call out to userspace.

Rename all arch-specific helpers to make it clear they're arch-specific,
and to avoid collisions with common helpers (one more on its way...)

Add WRITE_ONCE() to stores in ucall() code (as already done to aarch64
code in commit 9e2f6498 ("selftests: KVM: Handle compiler
optimizations in ucall")) to prevent clang optimizations breaking ucalls.

Cc: Colton Lewis <coltonlewis@google.com>
Reviewed-by: default avatarAndrew Jones <andrew.jones@linux.dev>
Tested-by: default avatarPeter Gonda <pgonda@google.com>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006003409.649993-2-seanjc@google.com
parent b3d93772

tools/testing/selftests/kvm/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -47,6 +47,7 @@ LIBKVM += lib/memstress.c 
LIBKVM += lib/rbtree.c

LIBKVM += lib/sparsebit.c

LIBKVM += lib/test_util.c

LIBKVM += lib/ucall_common.c



LIBKVM_STRING += lib/string_override.c

tools/testing/selftests/kvm/include/ucall_common.h

+20 −3
Original line number Diff line number Diff line
@@ -24,10 +24,27 @@ struct ucall { 
	uint64_t args[UCALL_MAX_ARGS];

};



void ucall_init(struct kvm_vm *vm, void *arg);

void ucall_uninit(struct kvm_vm *vm);

void ucall_arch_init(struct kvm_vm *vm, void *arg);

void ucall_arch_uninit(struct kvm_vm *vm);

void ucall_arch_do_ucall(vm_vaddr_t uc);

uint64_t ucall_arch_get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc);



void ucall(uint64_t cmd, int nargs, ...);

uint64_t get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc);



static inline void ucall_init(struct kvm_vm *vm, void *arg)

{

	ucall_arch_init(vm, arg);

}



static inline void ucall_uninit(struct kvm_vm *vm)

{

	ucall_arch_uninit(vm);

}



static inline uint64_t get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc)

{

	return ucall_arch_get_ucall(vcpu, uc);

}



#define GUEST_SYNC_ARGS(stage, arg1, arg2, arg3, arg4)	\

				ucall(UCALL_SYNC, 6, "hello", stage, arg1, arg2, arg3, arg4)

tools/testing/selftests/kvm/lib/aarch64/ucall.c

+5 −17
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ static bool ucall_mmio_init(struct kvm_vm *vm, vm_paddr_t gpa) 
	return true;

}



void ucall_init(struct kvm_vm *vm, void *arg)

void ucall_arch_init(struct kvm_vm *vm, void *arg)

{

	vm_paddr_t gpa, start, end, step, offset;

	unsigned int bits;
@@ -64,30 +64,18 @@ void ucall_init(struct kvm_vm *vm, void *arg) 
	TEST_FAIL("Can't find a ucall mmio address");

}



void ucall_uninit(struct kvm_vm *vm)

void ucall_arch_uninit(struct kvm_vm *vm)

{

	ucall_exit_mmio_addr = 0;

	sync_global_to_guest(vm, ucall_exit_mmio_addr);

}



void ucall(uint64_t cmd, int nargs, ...)

void ucall_arch_do_ucall(vm_vaddr_t uc)

{

	struct ucall uc = {};

	va_list va;

	int i;



	WRITE_ONCE(uc.cmd, cmd);

	nargs = min(nargs, UCALL_MAX_ARGS);



	va_start(va, nargs);

	for (i = 0; i < nargs; ++i)

		WRITE_ONCE(uc.args[i], va_arg(va, uint64_t));

	va_end(va);



	WRITE_ONCE(*ucall_exit_mmio_addr, (vm_vaddr_t)&uc);

	WRITE_ONCE(*ucall_exit_mmio_addr, uc);

}



uint64_t get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc)

uint64_t ucall_arch_get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc)

{

	struct kvm_run *run = vcpu->run;

	struct ucall ucall = {};

tools/testing/selftests/kvm/lib/riscv/ucall.c

+5 −18
Original line number Diff line number Diff line
@@ -10,11 +10,11 @@ 
#include "kvm_util.h"

#include "processor.h"



void ucall_init(struct kvm_vm *vm, void *arg)

void ucall_arch_init(struct kvm_vm *vm, void *arg)

{

}



void ucall_uninit(struct kvm_vm *vm)

void ucall_arch_uninit(struct kvm_vm *vm)

{

}
@@ -44,27 +44,14 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, 
	return ret;

}



void ucall(uint64_t cmd, int nargs, ...)

void ucall_arch_do_ucall(vm_vaddr_t uc)

{

	struct ucall uc = {

		.cmd = cmd,

	};

	va_list va;

	int i;



	nargs = min(nargs, UCALL_MAX_ARGS);



	va_start(va, nargs);

	for (i = 0; i < nargs; ++i)

		uc.args[i] = va_arg(va, uint64_t);

	va_end(va);



	sbi_ecall(KVM_RISCV_SELFTESTS_SBI_EXT,

		  KVM_RISCV_SELFTESTS_SBI_UCALL,

		  (vm_vaddr_t)&uc, 0, 0, 0, 0, 0);

		  uc, 0, 0, 0, 0, 0);

}



uint64_t get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc)

uint64_t ucall_arch_get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc)

{

	struct kvm_run *run = vcpu->run;

	struct ucall ucall = {};

tools/testing/selftests/kvm/lib/s390x/ucall.c

+5 −18
Original line number Diff line number Diff line
@@ -6,34 +6,21 @@ 
 */

#include "kvm_util.h"



void ucall_init(struct kvm_vm *vm, void *arg)

void ucall_arch_init(struct kvm_vm *vm, void *arg)

{

}



void ucall_uninit(struct kvm_vm *vm)

void ucall_arch_uninit(struct kvm_vm *vm)

{

}



void ucall(uint64_t cmd, int nargs, ...)

void ucall_arch_do_ucall(vm_vaddr_t uc)

{

	struct ucall uc = {

		.cmd = cmd,

	};

	va_list va;

	int i;



	nargs = min(nargs, UCALL_MAX_ARGS);



	va_start(va, nargs);

	for (i = 0; i < nargs; ++i)

		uc.args[i] = va_arg(va, uint64_t);

	va_end(va);



	/* Exit via DIAGNOSE 0x501 (normally used for breakpoints) */

	asm volatile ("diag 0,%0,0x501" : : "a"(&uc) : "memory");

	asm volatile ("diag 0,%0,0x501" : : "a"(uc) : "memory");

}



uint64_t get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc)

uint64_t ucall_arch_get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc)

{

	struct kvm_run *run = vcpu->run;

	struct ucall ucall = {};