lkml.org 
[lkml]   [2019]   [Sep]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v3 07/16] svm: Add support for setup/destroy virutal APIC backing page for AVIC
Date
Activate/deactivate AVIC requires setting/unsetting the memory region used
for virtual APIC backing page (APIC_ACCESS_PAGE_PRIVATE_MEMSLOT).
So, re-factor avic_init_access_page() to avic_setup_access_page()
and add srcu_read_lock/unlock, which are needed to allow this function
to be called during run-time.

Also, introduce avic_destroy_access_page() to unset the page when
deactivate AVIC.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
arch/x86/kvm/svm.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 47 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 8673617..2e06ee2 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1476,7 +1476,9 @@ static u64 svm_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
static void avic_init_vmcb(struct vcpu_svm *svm)
{
struct vmcb *vmcb = svm->vmcb;
- struct kvm_svm *kvm_svm = to_kvm_svm(svm->vcpu.kvm);
+ struct kvm *kvm = svm->vcpu.kvm;
+ struct kvm_svm *kvm_svm = to_kvm_svm(kvm);
+
phys_addr_t bpa = __sme_set(page_to_phys(svm->avic_backing_page));
phys_addr_t lpa = __sme_set(page_to_phys(kvm_svm->avic_logical_id_table_page));
phys_addr_t ppa = __sme_set(page_to_phys(kvm_svm->avic_physical_id_table_page));
@@ -1485,7 +1487,13 @@ static void avic_init_vmcb(struct vcpu_svm *svm)
vmcb->control.avic_logical_id = lpa & AVIC_HPA_MASK;
vmcb->control.avic_physical_id = ppa & AVIC_HPA_MASK;
vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID_COUNT;
- vmcb->control.int_ctl |= AVIC_ENABLE_MASK;
+
+ mutex_lock(&kvm->arch.apicv_lock);
+ if (kvm->arch.apicv_state == APICV_ACTIVATED)
+ vmcb->control.int_ctl |= AVIC_ENABLE_MASK;
+ else
+ vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK;
+ mutex_unlock(&kvm->arch.apicv_lock);
}

static void init_vmcb(struct vcpu_svm *svm)
@@ -1668,19 +1676,24 @@ static u64 *avic_get_physical_id_entry(struct kvm_vcpu *vcpu,
* field of the VMCB. Therefore, we set up the
* APIC_ACCESS_PAGE_PRIVATE_MEMSLOT (4KB) here.
*/
-static int avic_init_access_page(struct kvm_vcpu *vcpu)
+static int avic_setup_access_page(struct kvm_vcpu *vcpu, bool init)
{
struct kvm *kvm = vcpu->kvm;
int ret = 0;

mutex_lock(&kvm->slots_lock);
+
if (kvm->arch.apic_access_page_done)
goto out;

+ if (!init)
+ srcu_read_unlock(&kvm->srcu, vcpu->srcu_idx);
ret = __x86_set_memory_region(kvm,
APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
APIC_DEFAULT_PHYS_BASE,
PAGE_SIZE);
+ if (!init)
+ vcpu->srcu_idx = srcu_read_lock(&kvm->srcu);
if (ret)
goto out;

@@ -1690,14 +1703,39 @@ static int avic_init_access_page(struct kvm_vcpu *vcpu)
return ret;
}

+static void avic_destroy_access_page(struct kvm_vcpu *vcpu)
+{
+ struct kvm *kvm = vcpu->kvm;
+
+ mutex_lock(&kvm->slots_lock);
+
+ if (!kvm->arch.apic_access_page_done)
+ goto out;
+
+ srcu_read_unlock(&kvm->srcu, vcpu->srcu_idx);
+ __x86_set_memory_region(kvm,
+ APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
+ APIC_DEFAULT_PHYS_BASE,
+ 0);
+ vcpu->srcu_idx = srcu_read_lock(&kvm->srcu);
+ kvm->arch.apic_access_page_done = false;
+out:
+ mutex_unlock(&kvm->slots_lock);
+}
+
static int avic_init_backing_page(struct kvm_vcpu *vcpu)
{
- int ret;
+ int ret = 0;
u64 *entry, new_entry;
int id = vcpu->vcpu_id;
+ struct kvm *kvm = vcpu->kvm;
struct vcpu_svm *svm = to_svm(vcpu);

- ret = avic_init_access_page(vcpu);
+ mutex_lock(&kvm->arch.apicv_lock);
+ if (kvm->arch.apicv_state == APICV_ACTIVATED)
+ ret = avic_setup_access_page(vcpu, true);
+ mutex_unlock(&kvm->arch.apicv_lock);
+
if (ret)
return ret;

@@ -2187,7 +2225,10 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
/* We initialize this flag to true to make sure that the is_running
* bit would be set the first time the vcpu is loaded.
*/
- svm->avic_is_running = true;
+ mutex_lock(&kvm->arch.apicv_lock);
+ if (irqchip_in_kernel(kvm) && kvm->arch.apicv_state == APICV_ACTIVATED)
+ svm->avic_is_running = true;
+ mutex_unlock(&kvm->arch.apicv_lock);

svm->nested.hsave = page_address(hsave_page);

--
1.8.3.1
\
 
 \ /
  Last update: 2019-09-13 21:03    [W:0.167 / U:7.244 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site