2020-01-30 00:11:52

by Sean Christopherson

Subject: [PATCH 1/5] KVM: Pass kvm_init()'s opaque param to additional arch funcs

Pass @opaque to kvm_arch_hardware_setup() and
kvm_arch_check_processor_compat() to allow architecture specific code to
reference @opaque without having to stash it away in a temporary global
variable. This will enable x86 to separate its vendor specific callback
ops, which are passed via @opaque, into "init" and "runtime" ops without
having to stash away the "init" ops.

No functional change intended.

Signed-off-by: Sean Christopherson <[email protected]>
---
arch/mips/kvm/mips.c | 4 ++--
arch/powerpc/kvm/powerpc.c | 4 ++--
arch/s390/kvm/kvm-s390.c | 4 ++--
arch/x86/kvm/x86.c | 4 ++--
include/linux/kvm_host.h | 4 ++--
virt/kvm/arm/arm.c | 4 ++--
virt/kvm/kvm_main.c | 18 ++++++++++++++----
7 files changed, 26 insertions(+), 16 deletions(-)

diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 2606f3f02b54..664a3fcab80a 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -118,12 +118,12 @@ void kvm_arch_hardware_disable(void)
kvm_mips_callbacks->hardware_disable();
}

-int kvm_arch_hardware_setup(void)
+int kvm_arch_hardware_setup(void *opaque)
{
return 0;
}

-int kvm_arch_check_processor_compat(void)
+int kvm_arch_check_processor_compat(void *opaque)
{
return 0;
}
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 1af96fb5dc6f..ffa9d0ac5390 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -416,12 +416,12 @@ int kvm_arch_hardware_enable(void)
return 0;
}

-int kvm_arch_hardware_setup(void)
+int kvm_arch_hardware_setup(void *opaque)
{
return 0;
}

-int kvm_arch_check_processor_compat(void)
+int kvm_arch_check_processor_compat(void *opaque)
{
return kvmppc_core_check_processor_compat();
}
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8646c99217f2..6de2183db936 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -228,7 +228,7 @@ int kvm_arch_hardware_enable(void)
return 0;
}

-int kvm_arch_check_processor_compat(void)
+int kvm_arch_check_processor_compat(void *opaque)
{
return 0;
}
@@ -293,7 +293,7 @@ static struct notifier_block kvm_clock_notifier = {
.notifier_call = kvm_clock_sync,
};

-int kvm_arch_hardware_setup(void)
+int kvm_arch_hardware_setup(void *opaque)
{
gmap_notifier.notifier_call = kvm_gmap_notifier;
gmap_register_pte_notifier(&gmap_notifier);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7e3f1d937224..720fd7136712 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9579,7 +9579,7 @@ void kvm_arch_hardware_disable(void)
drop_user_return_notifiers();
}

-int kvm_arch_hardware_setup(void)
+int kvm_arch_hardware_setup(void *opaque)
{
int r;

@@ -9615,7 +9615,7 @@ void kvm_arch_hardware_unsetup(void)
kvm_x86_ops->hardware_unsetup();
}

-int kvm_arch_check_processor_compat(void)
+int kvm_arch_check_processor_compat(void *opaque)
{
struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 6d5331b0d937..7ffef8e793f8 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -877,9 +877,9 @@ void kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu);

int kvm_arch_hardware_enable(void);
void kvm_arch_hardware_disable(void);
-int kvm_arch_hardware_setup(void);
+int kvm_arch_hardware_setup(void *opaque);
void kvm_arch_hardware_unsetup(void);
-int kvm_arch_check_processor_compat(void);
+int kvm_arch_check_processor_compat(void *opaque);
int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu);
bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu);
int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu);
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 3ff510599af6..18d316d549a9 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -66,12 +66,12 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
}

-int kvm_arch_hardware_setup(void)
+int kvm_arch_hardware_setup(void *opaque)
{
return 0;
}

-int kvm_arch_check_processor_compat(void)
+int kvm_arch_check_processor_compat(void *opaque)
{
return 0;
}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index eb3709d55139..5ad252defa54 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -4345,14 +4345,22 @@ struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
return &kvm_running_vcpu;
}

-static void check_processor_compat(void *rtn)
+struct kvm_cpu_compat_check {
+ void *opaque;
+ int *ret;
+};
+
+static void check_processor_compat(void *data)
{
- *(int *)rtn = kvm_arch_check_processor_compat();
+ struct kvm_cpu_compat_check *c = data;
+
+ *c->ret = kvm_arch_check_processor_compat(c->opaque);
}

int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
{
+ struct kvm_cpu_compat_check c;
int r;
int cpu;

@@ -4376,12 +4384,14 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
goto out_free_0;
}

- r = kvm_arch_hardware_setup();
+ r = kvm_arch_hardware_setup(opaque);
if (r < 0)
goto out_free_1;

+ c.ret = &r;
+ c.opaque = opaque;
for_each_online_cpu(cpu) {
- smp_call_function_single(cpu, check_processor_compat, &r, 1);
+ smp_call_function_single(cpu, check_processor_compat, &c, 1);
if (r < 0)
goto out_free_2;
}
--
2.24.1

2020-01-31 12:07:57

by Cornelia Huck

Subject: Re: [PATCH 1/5] KVM: Pass kvm_init()'s opaque param to additional arch funcs

On Wed, 29 Jan 2020 16:10:19 -0800
Sean Christopherson <[email protected]> wrote:

> Pass @opaque to kvm_arch_hardware_setup() and
> kvm_arch_check_processor_compat() to allow architecture specific code to
> reference @opaque without having to stash it away in a temporary global
> variable. This will enable x86 to separate its vendor specific callback
> ops, which are passed via @opaque, into "init" and "runtime" ops without
> having to stash away the "init" ops.
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <[email protected]>
> ---
> arch/mips/kvm/mips.c | 4 ++--
> arch/powerpc/kvm/powerpc.c | 4 ++--
> arch/s390/kvm/kvm-s390.c | 4 ++--
> arch/x86/kvm/x86.c | 4 ++--
> include/linux/kvm_host.h | 4 ++--
> virt/kvm/arm/arm.c | 4 ++--
> virt/kvm/kvm_main.c | 18 ++++++++++++++----
> 7 files changed, 26 insertions(+), 16 deletions(-)

> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index eb3709d55139..5ad252defa54 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -4345,14 +4345,22 @@ struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
> return &kvm_running_vcpu;
> }
>
> -static void check_processor_compat(void *rtn)
> +struct kvm_cpu_compat_check {
> + void *opaque;
> + int *ret;
> +};
> +
> +static void check_processor_compat(void *data)
> {
> - *(int *)rtn = kvm_arch_check_processor_compat();
> + struct kvm_cpu_compat_check *c = data;
> +
> + *c->ret = kvm_arch_check_processor_compat(c->opaque);
> }

This function also looks better now :)

Reviewed-by: Cornelia Huck <[email protected]>
Tested-by: Cornelia Huck <[email protected]> #s390