diff options
| -rw-r--r-- | arch/x86/kernel/kvm.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index a8e36da6012..cbadc730496 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -25,6 +25,7 @@ #include <linux/kvm_para.h> #include <linux/cpu.h> #include <linux/mm.h> +#include <linux/highmem.h> /* * No need for any "IO delay" on KVM @@ -33,6 +34,122 @@ static void kvm_io_delay(void) { } +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 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_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_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 paravirt_ops_setup(void) { pv_info.name = "KVM"; @@ -41,6 +158,27 @@ static void paravirt_ops_setup(void) 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; + } } void __init kvm_guest_init(void) |