lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

KVM: MMU: Switch to mmu spinlock

Browse Source 
Convert the synchronization of the shadow handling to a separate mmu_lock
spinlock.

Also guard fetch() by mmap_sem in read-mode to protect against alias
and memslot changes.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Marcelo Tosatti
2007-12-20 19:18:26 -05:00
committed by Avi Kivity
parent d7824fff89
commit aaee2c94f7
5 changed files with 35 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
arch/x86/kvm/mmu.c
View File

@@ -971,16 +971,12 @@ static void nonpaging_new_cr3(struct kvm_vcpu *vcpu)
{
}
static int __nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
static int __nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write,
gfn_t gfn, struct page *page)
{
int level = PT32E_ROOT_LEVEL;
hpa_t table_addr = vcpu->arch.mmu.root_hpa;
int pt_write = 0;
struct page *page;
down_read(&current->mm->mmap_sem);
page = gfn_to_page(vcpu->kvm, gfn);
up_read(&current->mm->mmap_sem);
for (; ; level--) {
u32 index = PT64_INDEX(v, level);
@@ -1022,9 +1018,17 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
{
int r;
mutex_lock(&vcpu->kvm->lock);
r = __nonpaging_map(vcpu, v, write, gfn);
mutex_unlock(&vcpu->kvm->lock);
struct page *page;
down_read(&current->mm->mmap_sem);
page = gfn_to_page(vcpu->kvm, gfn);
spin_lock(&vcpu->kvm->mmu_lock);
r = __nonpaging_map(vcpu, v, write, gfn, page);
spin_unlock(&vcpu->kvm->mmu_lock);
up_read(&current->mm->mmap_sem);
return r;
}
@@ -1045,7 +1049,7 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
return;
mutex_lock(&vcpu->kvm->lock);
spin_lock(&vcpu->kvm->mmu_lock);
#ifdef CONFIG_X86_64
if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
hpa_t root = vcpu->arch.mmu.root_hpa;
@@ -1053,7 +1057,7 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
sp = page_header(root);
--sp->root_count;
vcpu->arch.mmu.root_hpa = INVALID_PAGE;
mutex_unlock(&vcpu->kvm->lock);
spin_unlock(&vcpu->kvm->mmu_lock);
return;
}
#endif
@@ -1067,7 +1071,7 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
}
vcpu->arch.mmu.pae_root[i] = INVALID_PAGE;
}
mutex_unlock(&vcpu->kvm->lock);
spin_unlock(&vcpu->kvm->mmu_lock);
vcpu->arch.mmu.root_hpa = INVALID_PAGE;
}
@@ -1270,9 +1274,9 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
r = mmu_topup_memory_caches(vcpu);
if (r)
goto out;
mutex_lock(&vcpu->kvm->lock);
spin_lock(&vcpu->kvm->mmu_lock);
mmu_alloc_roots(vcpu);
mutex_unlock(&vcpu->kvm->lock);
spin_unlock(&vcpu->kvm->mmu_lock);
kvm_x86_ops->set_cr3(vcpu, vcpu->arch.mmu.root_hpa);
kvm_mmu_flush_tlb(vcpu);
out:
@@ -1408,7 +1412,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
pgprintk("%s: gpa %llx bytes %d\n", __FUNCTION__, gpa, bytes);
mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes);
mutex_lock(&vcpu->kvm->lock);
spin_lock(&vcpu->kvm->mmu_lock);
++vcpu->kvm->stat.mmu_pte_write;
kvm_mmu_audit(vcpu, "pre pte write");
if (gfn == vcpu->arch.last_pt_write_gfn
@@ -1477,7 +1481,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
}
}
kvm_mmu_audit(vcpu, "post pte write");
mutex_unlock(&vcpu->kvm->lock);
spin_unlock(&vcpu->kvm->mmu_lock);
if (vcpu->arch.update_pte.page) {
kvm_release_page_clean(vcpu->arch.update_pte.page);
vcpu->arch.update_pte.page = NULL;
@@ -1493,15 +1497,15 @@ int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)
gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva);
up_read(&current->mm->mmap_sem);
mutex_lock(&vcpu->kvm->lock);
spin_lock(&vcpu->kvm->mmu_lock);
r = kvm_mmu_unprotect_page(vcpu->kvm, gpa >> PAGE_SHIFT);
mutex_unlock(&vcpu->kvm->lock);
spin_unlock(&vcpu->kvm->mmu_lock);
return r;
}
void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)
{
mutex_lock(&vcpu->kvm->lock);
spin_lock(&vcpu->kvm->mmu_lock);
while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES) {
struct kvm_mmu_page *sp;
@@ -1510,7 +1514,7 @@ void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)
kvm_mmu_zap_page(vcpu->kvm, sp);
++vcpu->kvm->stat.mmu_recycled;
}
mutex_unlock(&vcpu->kvm->lock);
spin_unlock(&vcpu->kvm->mmu_lock);
}
int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code)
@@ -1642,10 +1646,10 @@ void kvm_mmu_zap_all(struct kvm *kvm)
{
struct kvm_mmu_page *sp, *node;
mutex_lock(&kvm->lock);
spin_lock(&kvm->mmu_lock);
list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link)
kvm_mmu_zap_page(kvm, sp);
mutex_unlock(&kvm->lock);
spin_unlock(&kvm->mmu_lock);
kvm_flush_remote_tlbs(kvm);
}