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Diffstat (limited to 'arch/x86/kvm/mmu.c')
-rw-r--r--arch/x86/kvm/mmu.c136
1 files changed, 135 insertions, 1 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 414405b6ec13..072e9422c914 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -28,6 +28,7 @@
#include <linux/module.h>
#include <linux/swap.h>
#include <linux/hugetlb.h>
+#include <linux/compiler.h>
#include <asm/page.h>
#include <asm/cmpxchg.h>
@@ -40,7 +41,7 @@
* 2. while doing 1. it walks guest-physical to host-physical
* If the hardware supports that we don't need to do shadow paging.
*/
-static bool tdp_enabled = false;
+bool tdp_enabled = false;
#undef MMU_DEBUG
@@ -167,6 +168,13 @@ static int dbg = 1;
#define ACC_USER_MASK PT_USER_MASK
#define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
+struct kvm_pv_mmu_op_buffer {
+ void *ptr;
+ unsigned len;
+ unsigned processed;
+ char buf[512] __aligned(sizeof(long));
+};
+
struct kvm_rmap_desc {
u64 *shadow_ptes[RMAP_EXT];
struct kvm_rmap_desc *more;
@@ -2003,6 +2011,132 @@ unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm)
return nr_mmu_pages;
}
+static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer *buffer,
+ unsigned len)
+{
+ if (len > buffer->len)
+ return NULL;
+ return buffer->ptr;
+}
+
+static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer *buffer,
+ unsigned len)
+{
+ void *ret;
+
+ ret = pv_mmu_peek_buffer(buffer, len);
+ if (!ret)
+ return ret;
+ buffer->ptr += len;
+ buffer->len -= len;
+ buffer->processed += len;
+ return ret;
+}
+
+static int kvm_pv_mmu_write(struct kvm_vcpu *vcpu,
+ gpa_t addr, gpa_t value)
+{
+ int bytes = 8;
+ int r;
+
+ if (!is_long_mode(vcpu) && !is_pae(vcpu))
+ bytes = 4;
+
+ r = mmu_topup_memory_caches(vcpu);
+ if (r)
+ return r;
+
+ if (!__emulator_write_phys(vcpu, addr, &value, bytes))
+ return -EFAULT;
+
+ return 1;
+}
+
+static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu *vcpu)
+{
+ kvm_x86_ops->tlb_flush(vcpu);
+ return 1;
+}
+
+static int kvm_pv_mmu_release_pt(struct kvm_vcpu *vcpu, gpa_t addr)
+{
+ spin_lock(&vcpu->kvm->mmu_lock);
+ mmu_unshadow(vcpu->kvm, addr >> PAGE_SHIFT);
+ spin_unlock(&vcpu->kvm->mmu_lock);
+ return 1;
+}
+
+static int kvm_pv_mmu_op_one(struct kvm_vcpu *vcpu,
+ struct kvm_pv_mmu_op_buffer *buffer)
+{
+ struct kvm_mmu_op_header *header;
+
+ header = pv_mmu_peek_buffer(buffer, sizeof *header);
+ if (!header)
+ return 0;
+ switch (header->op) {
+ case KVM_MMU_OP_WRITE_PTE: {
+ struct kvm_mmu_op_write_pte *wpte;
+
+ wpte = pv_mmu_read_buffer(buffer, sizeof *wpte);
+ if (!wpte)
+ return 0;
+ return kvm_pv_mmu_write(vcpu, wpte->pte_phys,
+ wpte->pte_val);
+ }
+ case KVM_MMU_OP_FLUSH_TLB: {
+ struct kvm_mmu_op_flush_tlb *ftlb;
+
+ ftlb = pv_mmu_read_buffer(buffer, sizeof *ftlb);
+ if (!ftlb)
+ return 0;
+ return kvm_pv_mmu_flush_tlb(vcpu);
+ }
+ case KVM_MMU_OP_RELEASE_PT: {
+ struct kvm_mmu_op_release_pt *rpt;
+
+ rpt = pv_mmu_read_buffer(buffer, sizeof *rpt);
+ if (!rpt)
+ return 0;
+ return kvm_pv_mmu_release_pt(vcpu, rpt->pt_phys);
+ }
+ default: return 0;
+ }
+}
+
+int kvm_pv_mmu_op(struct kvm_vcpu *vcpu, unsigned long bytes,
+ gpa_t addr, unsigned long *ret)
+{
+ int r;
+ struct kvm_pv_mmu_op_buffer buffer;
+
+ down_read(&vcpu->kvm->slots_lock);
+ down_read(&current->mm->mmap_sem);
+
+ buffer.ptr = buffer.buf;
+ buffer.len = min_t(unsigned long, bytes, sizeof buffer.buf);
+ buffer.processed = 0;
+
+ r = kvm_read_guest(vcpu->kvm, addr, buffer.buf, buffer.len);
+ if (r)
+ goto out;
+
+ while (buffer.len) {
+ r = kvm_pv_mmu_op_one(vcpu, &buffer);
+ if (r < 0)
+ goto out;
+ if (r == 0)
+ break;
+ }
+
+ r = 1;
+out:
+ *ret = buffer.processed;
+ up_read(&current->mm->mmap_sem);
+ up_read(&vcpu->kvm->slots_lock);
+ return r;
+}
+
#ifdef AUDIT
static const char *audit_msg;