[PATCH v2 1/9] KVM: add kvm_{test,clear}_request to replace {test,clear}_bit

Radim Krčmář
2017-04-26T20:32:19Z

Users were expected to use kvm_check_request() for testing and clearing,
but request have expanded their use since then and some users want to
only test or do a faster clear.

Make sure that requests are not directly accessed with bit operations.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
---
arch/mips/kvm/emulate.c | 2 +-
arch/powerpc/kvm/book3s_pr.c | 2 +-
arch/powerpc/kvm/book3s_pr_papr.c | 2 +-
arch/powerpc/kvm/booke.c | 4 ++--
arch/powerpc/kvm/powerpc.c | 2 +-
arch/s390/kvm/kvm-s390.c | 2 +-
arch/x86/kvm/vmx.c | 2 +-
arch/x86/kvm/x86.c | 8 ++++----
include/linux/kvm_host.h | 14 ++++++++++++--
9 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c
index 34e78a3ee9d7..4144bfaef137 100644
--- a/arch/mips/kvm/emulate.c
+++ b/arch/mips/kvm/emulate.c
@@ -982,7 +982,7 @@ enum emulation_result kvm_mips_emul_wait(struct kvm_vcpu *vcpu)
* check if any I/O interrupts are pending.
*/
if (kvm_check_request(KVM_REQ_UNHALT, vcpu)) {
- clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_UNHALT, vcpu);
vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
}
}
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index f026b062c0ed..69a09444d46e 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -349,7 +349,7 @@ static void kvmppc_set_msr_pr(struct kvm_vcpu *vcpu, u64 msr)
if (msr & MSR_POW) {
if (!vcpu->arch.pending_exceptions) {
kvm_vcpu_block(vcpu);
- clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_UNHALT, vcpu);
vcpu->stat.halt_wakeup++;

/* Unset POW bit after we woke up */
diff --git a/arch/powerpc/kvm/book3s_pr_papr.c b/arch/powerpc/kvm/book3s_pr_papr.c
index f102616febc7..bcbeeb62dd13 100644
--- a/arch/powerpc/kvm/book3s_pr_papr.c
+++ b/arch/powerpc/kvm/book3s_pr_papr.c
@@ -344,7 +344,7 @@ int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd)
case H_CEDE:
kvmppc_set_msr_fast(vcpu, kvmppc_get_msr(vcpu) | MSR_EE);
kvm_vcpu_block(vcpu);
- clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_UNHALT, vcpu);
vcpu->stat.halt_wakeup++;
return EMULATE_DONE;
case H_LOGICAL_CI_LOAD:
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 3c296c2eacf8..3eaac3809977 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -584,7 +584,7 @@ static void arm_next_watchdog(struct kvm_vcpu *vcpu)
* userspace, so clear the KVM_REQ_WATCHDOG request.
*/
if ((vcpu->arch.tsr & (TSR_ENW | TSR_WIS)) != (TSR_ENW | TSR_WIS))
- clear_bit(KVM_REQ_WATCHDOG, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_WATCHDOG, vcpu);

spin_lock_irqsave(&vcpu->arch.wdt_lock, flags);
nr_jiffies = watchdog_next_timeout(vcpu);
@@ -695,7 +695,7 @@ int kvmppc_core_prepare_to_enter(struct kvm_vcpu *vcpu)
if (vcpu->arch.shared->msr & MSR_WE) {
local_irq_enable();
kvm_vcpu_block(vcpu);
- clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_UNHALT, vcpu);
hard_irq_disable();

kvmppc_set_exit_type(vcpu, EMULATED_MTMSRWE_EXITS);
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index cf725c580fc5..1ee22a910074 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -233,7 +233,7 @@ int kvmppc_kvm_pv(struct kvm_vcpu *vcpu)
case EV_HCALL_TOKEN(EV_IDLE):
r = EV_SUCCESS;
kvm_vcpu_block(vcpu);
- clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_UNHALT, vcpu);
break;
default:
r = EV_UNIMPLEMENTED;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8771fef112a1..71a5f4023f3f 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -2492,7 +2492,7 @@ static int kvm_s390_handle_requests(struct kvm_vcpu *vcpu)
}

/* nothing to do, just clear the request */
- clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_UNHALT, vcpu);

return 0;
}
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index a4ef63718101..b003b8dfb20c 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6299,7 +6299,7 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
if (intr_window_requested && vmx_interrupt_allowed(vcpu))
return handle_interrupt_window(&vmx->vcpu);

- if (test_bit(KVM_REQ_EVENT, &vcpu->requests))
+ if (kvm_test_request(KVM_REQ_EVENT, vcpu))
return 1;

err = emulate_instruction(vcpu, EMULTYPE_NO_REEXECUTE);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f68c5b2ba627..2de54c20fa9e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1753,7 +1753,7 @@ static void kvm_gen_update_masterclock(struct kvm *kvm)

/* guest entries allowed */
kvm_for_each_vcpu(i, vcpu, kvm)
- clear_bit(KVM_REQ_MCLOCK_INPROGRESS, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_MCLOCK_INPROGRESS, vcpu);

spin_unlock(&ka->pvclock_gtod_sync_lock);
#endif
@@ -7041,7 +7041,7 @@ static int vcpu_run(struct kvm_vcpu *vcpu)
if (r <= 0)
break;

- clear_bit(KVM_REQ_PENDING_TIMER, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_PENDING_TIMER, vcpu);
if (kvm_cpu_has_pending_timer(vcpu))
kvm_inject_pending_timer_irqs(vcpu);

@@ -7169,7 +7169,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) {
kvm_vcpu_block(vcpu);
kvm_apic_accept_events(vcpu);
- clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+ kvm_clear_request(KVM_REQ_UNHALT, vcpu);
r = -EAGAIN;
goto out;
}
@@ -8382,7 +8382,7 @@ static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu)
if (atomic_read(&vcpu->arch.nmi_queued))
return true;

- if (test_bit(KVM_REQ_SMI, &vcpu->requests))
+ if (kvm_test_request(KVM_REQ_SMI, vcpu))
return true;

if (kvm_arch_interrupt_allowed(vcpu) &&
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 397b7b5b1933..374fa92c7657 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1079,10 +1079,20 @@ static inline void kvm_make_request(int req, struct kvm_vcpu *vcpu)
set_bit(req, &vcpu->requests);
}

+static inline bool kvm_test_request(int req, struct kvm_vcpu *vcpu)
+{
+ return test_bit(req, &vcpu->requests);
+}
+
+static inline void kvm_clear_request(int req, struct kvm_vcpu *vcpu)
+{
+ clear_bit(req, &vcpu->requests);
+}
+
static inline bool kvm_check_request(int req, struct kvm_vcpu *vcpu)
{
- if (test_bit(req, &vcpu->requests)) {
- clear_bit(req, &vcpu->requests);
+ if (kvm_test_request(req, vcpu)) {
+ kvm_clear_request(req, vcpu);

/*
* Ensure the rest of the request is visible to kvm_check_request's
--
2.12.2