KVM: MMU: Bail out immediately if there is no available mmu page

Bailing out immediately if there is no available mmu page to alloc.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Wanpeng Li 2017-08-10 16:28:02 -07:00 committed by Paolo Bonzini
parent 42bcbebf11
commit 26eeb53cf0
2 changed files with 29 additions and 10 deletions

View File

@ -3257,7 +3257,7 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level,
static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
gva_t gva, kvm_pfn_t *pfn, bool write, bool *writable);
static void make_mmu_pages_available(struct kvm_vcpu *vcpu);
static int make_mmu_pages_available(struct kvm_vcpu *vcpu);
static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code,
gfn_t gfn, bool prefault)
@ -3297,7 +3297,8 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code,
spin_lock(&vcpu->kvm->mmu_lock);
if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
goto out_unlock;
make_mmu_pages_available(vcpu);
if (make_mmu_pages_available(vcpu) < 0)
goto out_unlock;
if (likely(!force_pt_level))
transparent_hugepage_adjust(vcpu, &gfn, &pfn, &level);
r = __direct_map(vcpu, write, map_writable, level, gfn, pfn, prefault);
@ -3376,7 +3377,10 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu)
if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
spin_lock(&vcpu->kvm->mmu_lock);
make_mmu_pages_available(vcpu);
if(make_mmu_pages_available(vcpu) < 0) {
spin_unlock(&vcpu->kvm->mmu_lock);
return 1;
}
sp = kvm_mmu_get_page(vcpu, 0, 0, PT64_ROOT_LEVEL, 1, ACC_ALL);
++sp->root_count;
spin_unlock(&vcpu->kvm->mmu_lock);
@ -3387,7 +3391,10 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu)
MMU_WARN_ON(VALID_PAGE(root));
spin_lock(&vcpu->kvm->mmu_lock);
make_mmu_pages_available(vcpu);
if (make_mmu_pages_available(vcpu) < 0) {
spin_unlock(&vcpu->kvm->mmu_lock);
return 1;
}
sp = kvm_mmu_get_page(vcpu, i << (30 - PAGE_SHIFT),
i << 30, PT32_ROOT_LEVEL, 1, ACC_ALL);
root = __pa(sp->spt);
@ -3424,7 +3431,10 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
MMU_WARN_ON(VALID_PAGE(root));
spin_lock(&vcpu->kvm->mmu_lock);
make_mmu_pages_available(vcpu);
if (make_mmu_pages_available(vcpu) < 0) {
spin_unlock(&vcpu->kvm->mmu_lock);
return 1;
}
sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL,
0, ACC_ALL);
root = __pa(sp->spt);
@ -3458,7 +3468,10 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
return 1;
}
spin_lock(&vcpu->kvm->mmu_lock);
make_mmu_pages_available(vcpu);
if (make_mmu_pages_available(vcpu) < 0) {
spin_unlock(&vcpu->kvm->mmu_lock);
return 1;
}
sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, PT32_ROOT_LEVEL,
0, ACC_ALL);
root = __pa(sp->spt);
@ -3867,7 +3880,8 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code,
spin_lock(&vcpu->kvm->mmu_lock);
if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
goto out_unlock;
make_mmu_pages_available(vcpu);
if (make_mmu_pages_available(vcpu) < 0)
goto out_unlock;
if (likely(!force_pt_level))
transparent_hugepage_adjust(vcpu, &gfn, &pfn, &level);
r = __direct_map(vcpu, write, map_writable, level, gfn, pfn, prefault);
@ -4786,12 +4800,12 @@ int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)
}
EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt);
static void make_mmu_pages_available(struct kvm_vcpu *vcpu)
static int make_mmu_pages_available(struct kvm_vcpu *vcpu)
{
LIST_HEAD(invalid_list);
if (likely(kvm_mmu_available_pages(vcpu->kvm) >= KVM_MIN_FREE_MMU_PAGES))
return;
return 0;
while (kvm_mmu_available_pages(vcpu->kvm) < KVM_REFILL_PAGES) {
if (!prepare_zap_oldest_mmu_page(vcpu->kvm, &invalid_list))
@ -4800,6 +4814,10 @@ static void make_mmu_pages_available(struct kvm_vcpu *vcpu)
++vcpu->kvm->stat.mmu_recycled;
}
kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
if (!kvm_mmu_available_pages(vcpu->kvm))
return -ENOSPC;
return 0;
}
int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u64 error_code,

View File

@ -819,7 +819,8 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
goto out_unlock;
kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT);
make_mmu_pages_available(vcpu);
if (make_mmu_pages_available(vcpu) < 0)
goto out_unlock;
if (!force_pt_level)
transparent_hugepage_adjust(vcpu, &walker.gfn, &pfn, &level);
r = FNAME(fetch)(vcpu, addr, &walker, write_fault,