#include <linux/kvm_para.h>
#include <linux/cpu.h>
#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/hardirq.h>
+
+#define MMU_QUEUE_SIZE 1024
+
+struct kvm_para_state {
+ u8 mmu_queue[MMU_QUEUE_SIZE];
+ int mmu_queue_len;
+ enum paravirt_lazy_mode mode;
+};
+
+static DEFINE_PER_CPU(struct kvm_para_state, para_state);
+
+static struct kvm_para_state *kvm_para_state(void)
+{
+ return &per_cpu(para_state, raw_smp_processor_id());
+}
/*
* No need for any "IO delay" on KVM
{
}
+static void kvm_mmu_op(void *buffer, unsigned len)
+{
+ int r;
+ unsigned long a1, a2;
+
+ do {
+ a1 = __pa(buffer);
+ a2 = 0; /* on i386 __pa() always returns <4G */
+ r = kvm_hypercall3(KVM_HC_MMU_OP, len, a1, a2);
+ buffer += r;
+ len -= r;
+ } while (len);
+}
+
+static void mmu_queue_flush(struct kvm_para_state *state)
+{
+ if (state->mmu_queue_len) {
+ kvm_mmu_op(state->mmu_queue, state->mmu_queue_len);
+ state->mmu_queue_len = 0;
+ }
+}
+
+static void kvm_deferred_mmu_op(void *buffer, int len)
+{
+ struct kvm_para_state *state = kvm_para_state();
+
+ if (state->mode != PARAVIRT_LAZY_MMU) {
+ kvm_mmu_op(buffer, len);
+ return;
+ }
+ if (state->mmu_queue_len + len > sizeof state->mmu_queue)
+ mmu_queue_flush(state);
+ memcpy(state->mmu_queue + state->mmu_queue_len, buffer, len);
+ state->mmu_queue_len += len;
+}
+
+static void kvm_mmu_write(void *dest, u64 val)
+{
+ __u64 pte_phys;
+ struct kvm_mmu_op_write_pte wpte;
+
+#ifdef CONFIG_HIGHPTE
+ struct page *page;
+ unsigned long dst = (unsigned long) dest;
+
+ page = kmap_atomic_to_page(dest);
+ pte_phys = page_to_pfn(page);
+ pte_phys <<= PAGE_SHIFT;
+ pte_phys += (dst & ~(PAGE_MASK));
+#else
+ pte_phys = (unsigned long)__pa(dest);
+#endif
+ wpte.header.op = KVM_MMU_OP_WRITE_PTE;
+ wpte.pte_val = val;
+ wpte.pte_phys = pte_phys;
+
+ kvm_deferred_mmu_op(&wpte, sizeof wpte);
+}
+
+/*
+ * We only need to hook operations that are MMU writes. We hook these so that
+ * we can use lazy MMU mode to batch these operations. We could probably
+ * improve the performance of the host code if we used some of the information
+ * here to simplify processing of batched writes.
+ */
+static void kvm_set_pte(pte_t *ptep, pte_t pte)
+{
+ kvm_mmu_write(ptep, pte_val(pte));
+}
+
+static void kvm_set_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ kvm_mmu_write(ptep, pte_val(pte));
+}
+
+static void kvm_set_pmd(pmd_t *pmdp, pmd_t pmd)
+{
+ kvm_mmu_write(pmdp, pmd_val(pmd));
+}
+
+#if PAGETABLE_LEVELS >= 3
+#ifdef CONFIG_X86_PAE
+static void kvm_set_pte_atomic(pte_t *ptep, pte_t pte)
+{
+ kvm_mmu_write(ptep, pte_val(pte));
+}
+
+static void kvm_set_pte_present(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ kvm_mmu_write(ptep, pte_val(pte));
+}
+
+static void kvm_pte_clear(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ kvm_mmu_write(ptep, 0);
+}
+
+static void kvm_pmd_clear(pmd_t *pmdp)
+{
+ kvm_mmu_write(pmdp, 0);
+}
+#endif
+
+static void kvm_set_pud(pud_t *pudp, pud_t pud)
+{
+ kvm_mmu_write(pudp, pud_val(pud));
+}
+
+#if PAGETABLE_LEVELS == 4
+static void kvm_set_pgd(pgd_t *pgdp, pgd_t pgd)
+{
+ kvm_mmu_write(pgdp, pgd_val(pgd));
+}
+#endif
+#endif /* PAGETABLE_LEVELS >= 3 */
+
+static void kvm_flush_tlb(void)
+{
+ struct kvm_mmu_op_flush_tlb ftlb = {
+ .header.op = KVM_MMU_OP_FLUSH_TLB,
+ };
+
+ kvm_deferred_mmu_op(&ftlb, sizeof ftlb);
+}
+
+static void kvm_release_pt(u32 pfn)
+{
+ struct kvm_mmu_op_release_pt rpt = {
+ .header.op = KVM_MMU_OP_RELEASE_PT,
+ .pt_phys = (u64)pfn << PAGE_SHIFT,
+ };
+
+ kvm_mmu_op(&rpt, sizeof rpt);
+}
+
+static void kvm_enter_lazy_mmu(void)
+{
+ struct kvm_para_state *state = kvm_para_state();
+
+ paravirt_enter_lazy_mmu();
+ state->mode = paravirt_get_lazy_mode();
+}
+
+static void kvm_leave_lazy_mmu(void)
+{
+ struct kvm_para_state *state = kvm_para_state();
+
+ mmu_queue_flush(state);
+ paravirt_leave_lazy(paravirt_get_lazy_mode());
+ state->mode = paravirt_get_lazy_mode();
+}
+
static void paravirt_ops_setup(void)
{
pv_info.name = "KVM";
if (kvm_para_has_feature(KVM_FEATURE_NOP_IO_DELAY))
pv_cpu_ops.io_delay = kvm_io_delay;
+ if (kvm_para_has_feature(KVM_FEATURE_MMU_OP)) {
+ pv_mmu_ops.set_pte = kvm_set_pte;
+ pv_mmu_ops.set_pte_at = kvm_set_pte_at;
+ pv_mmu_ops.set_pmd = kvm_set_pmd;
+#if PAGETABLE_LEVELS >= 3
+#ifdef CONFIG_X86_PAE
+ pv_mmu_ops.set_pte_atomic = kvm_set_pte_atomic;
+ pv_mmu_ops.set_pte_present = kvm_set_pte_present;
+ pv_mmu_ops.pte_clear = kvm_pte_clear;
+ pv_mmu_ops.pmd_clear = kvm_pmd_clear;
+#endif
+ pv_mmu_ops.set_pud = kvm_set_pud;
+#if PAGETABLE_LEVELS == 4
+ pv_mmu_ops.set_pgd = kvm_set_pgd;
+#endif
+#endif
+ pv_mmu_ops.flush_tlb_user = kvm_flush_tlb;
+ pv_mmu_ops.release_pte = kvm_release_pt;
+ pv_mmu_ops.release_pmd = kvm_release_pt;
+ pv_mmu_ops.release_pud = kvm_release_pt;
+
+ pv_mmu_ops.lazy_mode.enter = kvm_enter_lazy_mmu;
+ pv_mmu_ops.lazy_mode.leave = kvm_leave_lazy_mmu;
+ }
}
void __init kvm_guest_init(void)
projects / linux-2.6 / blobdiff