Re: [PATCH 1/3] KVM: selftests: Consolidate common code for popuplating ucall struct

Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> · Mon, 20 Jun 2022 09:39:50 +0200

Am 18.06.22 um 02:16 schrieb Sean Christopherson:
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...)

No functional change intended.

Cc: Colton Lewis <coltonlewis@xxxxxxxxxx>
Cc: Andrew Jones <drjones@xxxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>

seems to work on s390.
Tested-by: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx>

---
  tools/testing/selftests/kvm/Makefile          |  1 +
  .../selftests/kvm/include/ucall_common.h      | 23 ++++++++++++++++---
  .../testing/selftests/kvm/lib/aarch64/ucall.c | 23 ++++---------------
  tools/testing/selftests/kvm/lib/riscv/ucall.c | 23 ++++---------------
  tools/testing/selftests/kvm/lib/s390x/ucall.c | 23 ++++---------------
  .../testing/selftests/kvm/lib/ucall_common.c  | 20 ++++++++++++++++
  .../testing/selftests/kvm/lib/x86_64/ucall.c  | 23 ++++---------------
  7 files changed, 61 insertions(+), 75 deletions(-)
  create mode 100644 tools/testing/selftests/kvm/lib/ucall_common.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index b52c130f7b2f..bc2aee2af66c 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -46,6 +46,7 @@ LIBKVM += lib/perf_test_util.c
  LIBKVM += lib/rbtree.c
  LIBKVM += lib/sparsebit.c
  LIBKVM += lib/test_util.c
+LIBKVM += lib/ucall_common.c
  
  LIBKVM_x86_64 += lib/x86_64/apic.c
  LIBKVM_x86_64 += lib/x86_64/handlers.S
diff --git a/tools/testing/selftests/kvm/include/ucall_common.h b/tools/testing/selftests/kvm/include/ucall_common.h
index 98562f685151..c6a4fd7fe443 100644
--- a/tools/testing/selftests/kvm/include/ucall_common.h
+++ b/tools/testing/selftests/kvm/include/ucall_common.h
@@ -23,10 +23,27 @@ 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)
diff --git a/tools/testing/selftests/kvm/lib/aarch64/ucall.c b/tools/testing/selftests/kvm/lib/aarch64/ucall.c
index 0b949ee06b5e..2de9fdd34159 100644
--- a/tools/testing/selftests/kvm/lib/aarch64/ucall.c
+++ b/tools/testing/selftests/kvm/lib/aarch64/ucall.c
@@ -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;
@@ -64,31 +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 = {
-		.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);
-
-	*ucall_exit_mmio_addr = (vm_vaddr_t)&uc;
+	*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 = {};
diff --git a/tools/testing/selftests/kvm/lib/riscv/ucall.c b/tools/testing/selftests/kvm/lib/riscv/ucall.c
index 087b9740bc8f..b1598f418c1f 100644
--- a/tools/testing/selftests/kvm/lib/riscv/ucall.c
+++ b/tools/testing/selftests/kvm/lib/riscv/ucall.c
@@ -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 = {};
diff --git a/tools/testing/selftests/kvm/lib/s390x/ucall.c b/tools/testing/selftests/kvm/lib/s390x/ucall.c
index 73dc4e21190f..114cb4af295f 100644
--- a/tools/testing/selftests/kvm/lib/s390x/ucall.c
+++ b/tools/testing/selftests/kvm/lib/s390x/ucall.c
@@ -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 = {};
diff --git a/tools/testing/selftests/kvm/lib/ucall_common.c b/tools/testing/selftests/kvm/lib/ucall_common.c
new file mode 100644
index 000000000000..749ffdf23855
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/ucall_common.c
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include "kvm_util.h"
+
+void ucall(uint64_t cmd, int nargs, ...)
+{
+	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);
+
+	ucall_arch_do_ucall((vm_vaddr_t)&uc);
+}
diff --git a/tools/testing/selftests/kvm/lib/x86_64/ucall.c b/tools/testing/selftests/kvm/lib/x86_64/ucall.c
index e5f0f9e0d3ee..9f532dba1003 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/ucall.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/ucall.c
@@ -8,34 +8,21 @@
  
  #define UCALL_PIO_PORT ((uint16_t)0x1000)
  
-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);
-
  	asm volatile("in %[port], %%al"
-		: : [port] "d" (UCALL_PIO_PORT), "D" (&uc) : "rax", "memory");
+		: : [port] "d" (UCALL_PIO_PORT), "D" (uc) : "rax", "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 = {};






