diff options
Diffstat (limited to 'arch/x86/kvm/mmu.c')
-rw-r--r-- | arch/x86/kvm/mmu.c | 369 |
1 files changed, 187 insertions, 182 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 89a49fb46a27..b1ed0a1a5913 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -18,6 +18,7 @@ */ #include "mmu.h" +#include "x86.h" #include "kvm_cache_regs.h" #include <linux/kvm_host.h> @@ -29,6 +30,8 @@ #include <linux/swap.h> #include <linux/hugetlb.h> #include <linux/compiler.h> +#include <linux/srcu.h> +#include <linux/slab.h> #include <asm/page.h> #include <asm/cmpxchg.h> @@ -136,16 +139,6 @@ module_param(oos_shadow, bool, 0644); #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \ | PT64_NX_MASK) -#define PFERR_PRESENT_MASK (1U << 0) -#define PFERR_WRITE_MASK (1U << 1) -#define PFERR_USER_MASK (1U << 2) -#define PFERR_RSVD_MASK (1U << 3) -#define PFERR_FETCH_MASK (1U << 4) - -#define PT_PDPE_LEVEL 3 -#define PT_DIRECTORY_LEVEL 2 -#define PT_PAGE_TABLE_LEVEL 1 - #define RMAP_EXT 4 #define ACC_EXEC_MASK 1 @@ -153,6 +146,8 @@ module_param(oos_shadow, bool, 0644); #define ACC_USER_MASK PT_USER_MASK #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK) +#include <trace/events/kvm.h> + #define CREATE_TRACE_POINTS #include "mmutrace.h" @@ -178,12 +173,7 @@ struct kvm_shadow_walk_iterator { shadow_walk_okay(&(_walker)); \ shadow_walk_next(&(_walker))) - -struct kvm_unsync_walk { - int (*entry) (struct kvm_mmu_page *sp, struct kvm_unsync_walk *walk); -}; - -typedef int (*mmu_parent_walk_fn) (struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp); +typedef int (*mmu_parent_walk_fn) (struct kvm_mmu_page *sp); static struct kmem_cache *pte_chain_cache; static struct kmem_cache *rmap_desc_cache; @@ -227,9 +217,9 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, } EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes); -static int is_write_protection(struct kvm_vcpu *vcpu) +static bool is_write_protection(struct kvm_vcpu *vcpu) { - return vcpu->arch.cr0 & X86_CR0_WP; + return kvm_read_cr0_bits(vcpu, X86_CR0_WP); } static int is_cpuid_PSE36(void) @@ -239,7 +229,7 @@ static int is_cpuid_PSE36(void) static int is_nx(struct kvm_vcpu *vcpu) { - return vcpu->arch.shadow_efer & EFER_NX; + return vcpu->arch.efer & EFER_NX; } static int is_shadow_present_pte(u64 pte) @@ -253,7 +243,7 @@ static int is_large_pte(u64 pte) return pte & PT_PAGE_SIZE_MASK; } -static int is_writeble_pte(unsigned long pte) +static int is_writable_pte(unsigned long pte) { return pte & PT_WRITABLE_MASK; } @@ -331,7 +321,6 @@ static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache, page = alloc_page(GFP_KERNEL); if (!page) return -ENOMEM; - set_page_private(page, 0); cache->objects[cache->nobjs++] = page_address(page); } return 0; @@ -442,9 +431,9 @@ static void unaccount_shadowed(struct kvm *kvm, gfn_t gfn) int i; gfn = unalias_gfn(kvm, gfn); + slot = gfn_to_memslot_unaliased(kvm, gfn); for (i = PT_DIRECTORY_LEVEL; i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { - slot = gfn_to_memslot_unaliased(kvm, gfn); write_count = slot_largepage_idx(gfn, slot, i); *write_count -= 1; WARN_ON(*write_count < 0); @@ -470,24 +459,10 @@ static int has_wrprotected_page(struct kvm *kvm, static int host_mapping_level(struct kvm *kvm, gfn_t gfn) { - unsigned long page_size = PAGE_SIZE; - struct vm_area_struct *vma; - unsigned long addr; + unsigned long page_size; int i, ret = 0; - addr = gfn_to_hva(kvm, gfn); - if (kvm_is_error_hva(addr)) - return PT_PAGE_TABLE_LEVEL; - - down_read(¤t->mm->mmap_sem); - vma = find_vma(current->mm, addr); - if (!vma) - goto out; - - page_size = vma_kernel_pagesize(vma); - -out: - up_read(¤t->mm->mmap_sem); + page_size = kvm_host_page_size(kvm, gfn); for (i = PT_PAGE_TABLE_LEVEL; i < (PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES); ++i) { @@ -503,8 +478,7 @@ out: static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn) { struct kvm_memory_slot *slot; - int host_level; - int level = PT_PAGE_TABLE_LEVEL; + int host_level, level, max_level; slot = gfn_to_memslot(vcpu->kvm, large_gfn); if (slot && slot->dirty_bitmap) @@ -515,7 +489,10 @@ static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn) if (host_level == PT_PAGE_TABLE_LEVEL) return host_level; - for (level = PT_DIRECTORY_LEVEL; level <= host_level; ++level) + max_level = kvm_x86_ops->get_lpage_level() < host_level ? + kvm_x86_ops->get_lpage_level() : host_level; + + for (level = PT_DIRECTORY_LEVEL; level <= max_level; ++level) if (has_wrprotected_page(vcpu->kvm, large_gfn, level)) break; @@ -633,7 +610,7 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) pfn = spte_to_pfn(*spte); if (*spte & shadow_accessed_mask) kvm_set_pfn_accessed(pfn); - if (is_writeble_pte(*spte)) + if (is_writable_pte(*spte)) kvm_set_pfn_dirty(pfn); rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt], sp->role.level); if (!*rmapp) { @@ -662,6 +639,7 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) prev_desc = desc; desc = desc->more; } + pr_err("rmap_remove: %p %llx many->many\n", spte, *spte); BUG(); } } @@ -669,7 +647,6 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte) { struct kvm_rmap_desc *desc; - struct kvm_rmap_desc *prev_desc; u64 *prev_spte; int i; @@ -681,7 +658,6 @@ static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte) return NULL; } desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); - prev_desc = NULL; prev_spte = NULL; while (desc) { for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i) { @@ -708,7 +684,7 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn) BUG_ON(!spte); BUG_ON(!(*spte & PT_PRESENT_MASK)); rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte); - if (is_writeble_pte(*spte)) { + if (is_writable_pte(*spte)) { __set_spte(spte, *spte & ~PT_WRITABLE_MASK); write_protected = 1; } @@ -732,7 +708,7 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn) BUG_ON(!(*spte & PT_PRESENT_MASK)); BUG_ON((*spte & (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)) != (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)); pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte, *spte, gfn); - if (is_writeble_pte(*spte)) { + if (is_writable_pte(*spte)) { rmap_remove(kvm, spte); --kvm->stat.lpages; __set_spte(spte, shadow_trap_nonpresent_pte); @@ -787,7 +763,7 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, new_spte &= ~PT_WRITABLE_MASK; new_spte &= ~SPTE_HOST_WRITEABLE; - if (is_writeble_pte(*spte)) + if (is_writable_pte(*spte)) kvm_set_pfn_dirty(spte_to_pfn(*spte)); __set_spte(spte, new_spte); spte = rmap_next(kvm, rmapp, spte); @@ -805,35 +781,32 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, unsigned long data)) { int i, j; + int ret; int retval = 0; + struct kvm_memslots *slots; - /* - * If mmap_sem isn't taken, we can look the memslots with only - * the mmu_lock by skipping over the slots with userspace_addr == 0. - */ - for (i = 0; i < kvm->nmemslots; i++) { - struct kvm_memory_slot *memslot = &kvm->memslots[i]; + slots = kvm_memslots(kvm); + + for (i = 0; i < slots->nmemslots; i++) { + struct kvm_memory_slot *memslot = &slots->memslots[i]; unsigned long start = memslot->userspace_addr; unsigned long end; - /* mmu_lock protects userspace_addr */ - if (!start) - continue; - end = start + (memslot->npages << PAGE_SHIFT); if (hva >= start && hva < end) { gfn_t gfn_offset = (hva - start) >> PAGE_SHIFT; - retval |= handler(kvm, &memslot->rmap[gfn_offset], - data); + ret = handler(kvm, &memslot->rmap[gfn_offset], data); for (j = 0; j < KVM_NR_PAGE_SIZES - 1; ++j) { int idx = gfn_offset; idx /= KVM_PAGES_PER_HPAGE(PT_DIRECTORY_LEVEL + j); - retval |= handler(kvm, + ret |= handler(kvm, &memslot->lpage_info[j][idx].rmap_pde, data); } + trace_kvm_age_page(hva, memslot, ret); + retval |= ret; } } @@ -856,9 +829,15 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, u64 *spte; int young = 0; - /* always return old for EPT */ + /* + * Emulate the accessed bit for EPT, by checking if this page has + * an EPT mapping, and clearing it if it does. On the next access, + * a new EPT mapping will be established. + * This has some overhead, but not as much as the cost of swapping + * out actively used pages or breaking up actively used hugepages. + */ if (!shadow_accessed_mask) - return 0; + return kvm_unmap_rmapp(kvm, rmapp, data); spte = rmap_next(kvm, rmapp, NULL); while (spte) { @@ -937,7 +916,6 @@ static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE); set_page_private(virt_to_page(sp->spt), (unsigned long)sp); list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages); - INIT_LIST_HEAD(&sp->oos_link); bitmap_zero(sp->slot_bitmap, KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS); sp->multimapped = 0; sp->parent_pte = parent_pte; @@ -1021,8 +999,7 @@ static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp, } -static void mmu_parent_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, - mmu_parent_walk_fn fn) +static void mmu_parent_walk(struct kvm_mmu_page *sp, mmu_parent_walk_fn fn) { struct kvm_pte_chain *pte_chain; struct hlist_node *node; @@ -1031,8 +1008,8 @@ static void mmu_parent_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, if (!sp->multimapped && sp->parent_pte) { parent_sp = page_header(__pa(sp->parent_pte)); - fn(vcpu, parent_sp); - mmu_parent_walk(vcpu, parent_sp, fn); + fn(parent_sp); + mmu_parent_walk(parent_sp, fn); return; } hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) @@ -1040,8 +1017,8 @@ static void mmu_parent_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, if (!pte_chain->parent_ptes[i]) break; parent_sp = page_header(__pa(pte_chain->parent_ptes[i])); - fn(vcpu, parent_sp); - mmu_parent_walk(vcpu, parent_sp, fn); + fn(parent_sp); + mmu_parent_walk(parent_sp, fn); } } @@ -1078,16 +1055,15 @@ static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page *sp) } } -static int unsync_walk_fn(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) +static int unsync_walk_fn(struct kvm_mmu_page *sp) { kvm_mmu_update_parents_unsync(sp); return 1; } -static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu *vcpu, - struct kvm_mmu_page *sp) +static void kvm_mmu_mark_parents_unsync(struct kvm_mmu_page *sp) { - mmu_parent_walk(vcpu, sp, unsync_walk_fn); + mmu_parent_walk(sp, unsync_walk_fn); kvm_mmu_update_parents_unsync(sp); } @@ -1213,6 +1189,7 @@ static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn) static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp) { WARN_ON(!sp->unsync); + trace_kvm_mmu_sync_page(sp); sp->unsync = 0; --kvm->stat.mmu_unsync; } @@ -1221,12 +1198,11 @@ static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp); static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) { - if (sp->role.glevels != vcpu->arch.mmu.root_level) { + if (sp->role.cr4_pae != !!is_pae(vcpu)) { kvm_mmu_zap_page(vcpu->kvm, sp); return 1; } - trace_kvm_mmu_sync_page(sp); if (rmap_write_protect(vcpu->kvm, sp->gfn)) kvm_flush_remote_tlbs(vcpu->kvm); kvm_unlink_unsync_page(vcpu->kvm, sp); @@ -1343,6 +1319,8 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, role = vcpu->arch.mmu.base_role; role.level = level; role.direct = direct; + if (role.direct) + role.cr4_pae = 0; role.access = access; if (vcpu->arch.mmu.root_level <= PT32_ROOT_LEVEL) { quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level)); @@ -1363,7 +1341,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, mmu_page_add_parent_pte(vcpu, sp, parent_pte); if (sp->unsync_children) { set_bit(KVM_REQ_MMU_SYNC, &vcpu->requests); - kvm_mmu_mark_parents_unsync(vcpu, sp); + kvm_mmu_mark_parents_unsync(sp); } trace_kvm_mmu_get_page(sp, false); return sp; @@ -1502,8 +1480,8 @@ static int mmu_zap_unsync_children(struct kvm *kvm, for_each_sp(pages, sp, parents, i) { kvm_mmu_zap_page(kvm, sp); mmu_pages_clear_parents(&parents); + zapped++; } - zapped += pages.nr; kvm_mmu_pages_init(parent, &parents, &pages); } @@ -1554,14 +1532,16 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages) */ if (used_pages > kvm_nr_mmu_pages) { - while (used_pages > kvm_nr_mmu_pages) { + while (used_pages > kvm_nr_mmu_pages && + !list_empty(&kvm->arch.active_mmu_pages)) { struct kvm_mmu_page *page; page = container_of(kvm->arch.active_mmu_pages.prev, struct kvm_mmu_page, link); - kvm_mmu_zap_page(kvm, page); + used_pages -= kvm_mmu_zap_page(kvm, page); used_pages--; } + kvm_nr_mmu_pages = used_pages; kvm->arch.n_free_mmu_pages = 0; } else @@ -1583,13 +1563,14 @@ static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn) r = 0; index = kvm_page_table_hashfn(gfn); bucket = &kvm->arch.mmu_page_hash[index]; +restart: hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) if (sp->gfn == gfn && !sp->role.direct) { pgprintk("%s: gfn %lx role %x\n", __func__, gfn, sp->role.word); r = 1; if (kvm_mmu_zap_page(kvm, sp)) - n = bucket->first; + goto restart; } return r; } @@ -1603,19 +1584,21 @@ static void mmu_unshadow(struct kvm *kvm, gfn_t gfn) index = kvm_page_table_hashfn(gfn); bucket = &kvm->arch.mmu_page_hash[index]; +restart: hlist_for_each_entry_safe(sp, node, nn, bucket, hash_link) { if (sp->gfn == gfn && !sp->role.direct && !sp->role.invalid) { pgprintk("%s: zap %lx %x\n", __func__, gfn, sp->role.word); - kvm_mmu_zap_page(kvm, sp); + if (kvm_mmu_zap_page(kvm, sp)) + goto restart; } } } static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn) { - int slot = memslot_id(kvm, gfn_to_memslot(kvm, gfn)); + int slot = memslot_id(kvm, gfn); struct kvm_mmu_page *sp = page_header(__pa(pte)); __set_bit(slot, sp->slot_bitmap); @@ -1635,20 +1618,6 @@ static void mmu_convert_notrap(struct kvm_mmu_page *sp) } } -struct page *gva_to_page(struct kvm_vcpu *vcpu, gva_t gva) -{ - struct page *page; - - gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva); - - if (gpa == UNMAPPED_GVA) - return NULL; - - page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT); - - return page; -} - /* * The function is based on mtrr_type_lookup() in * arch/x86/kernel/cpu/mtrr/generic.c @@ -1761,7 +1730,6 @@ static int kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) struct kvm_mmu_page *s; struct hlist_node *node, *n; - trace_kvm_mmu_unsync_page(sp); index = kvm_page_table_hashfn(sp->gfn); bucket = &vcpu->kvm->arch.mmu_page_hash[index]; /* don't unsync if pagetable is shadowed with multiple roles */ @@ -1771,10 +1739,11 @@ static int kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) if (s->role.word != sp->role.word) return 1; } + trace_kvm_mmu_unsync_page(sp); ++vcpu->kvm->stat.mmu_unsync; sp->unsync = 1; - kvm_mmu_mark_parents_unsync(vcpu, sp); + kvm_mmu_mark_parents_unsync(sp); mmu_convert_notrap(sp); return 0; @@ -1846,13 +1815,16 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, spte |= PT_WRITABLE_MASK; + if (!tdp_enabled && !(pte_access & ACC_WRITE_MASK)) + spte &= ~PT_USER_MASK; + /* * Optimization: for pte sync, if spte was writable the hash * lookup is unnecessary (and expensive). Write protection * is responsibility of mmu_get_page / kvm_sync_page. * Same reasoning can be applied to dirty page accounting. */ - if (!can_unsync && is_writeble_pte(*sptep)) + if (!can_unsync && is_writable_pte(*sptep)) goto set_pte; if (mmu_need_write_protect(vcpu, gfn, can_unsync)) { @@ -1860,7 +1832,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, __func__, gfn); ret = 1; pte_access &= ~ACC_WRITE_MASK; - if (is_writeble_pte(spte)) + if (is_writable_pte(spte)) spte &= ~PT_WRITABLE_MASK; } } @@ -1881,7 +1853,7 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, bool reset_host_protection) { int was_rmapped = 0; - int was_writeble = is_writeble_pte(*sptep); + int was_writable = is_writable_pte(*sptep); int rmap_count; pgprintk("%s: spte %llx access %x write_fault %d" @@ -1901,10 +1873,14 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, child = page_header(pte & PT64_BASE_ADDR_MASK); mmu_page_remove_parent_pte(child, sptep); + __set_spte(sptep, shadow_trap_nonpresent_pte); + kvm_flush_remote_tlbs(vcpu->kvm); } else if (pfn != spte_to_pfn(*sptep)) { pgprintk("hfn old %lx new %lx\n", spte_to_pfn(*sptep), pfn); rmap_remove(vcpu->kvm, sptep); + __set_spte(sptep, shadow_trap_nonpresent_pte); + kvm_flush_remote_tlbs(vcpu->kvm); } else was_rmapped = 1; } @@ -1932,7 +1908,7 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, if (rmap_count > RMAP_RECYCLE_THRESHOLD) rmap_recycle(vcpu, sptep, gfn); } else { - if (was_writeble) + if (was_writable) kvm_release_pfn_dirty(pfn); else kvm_release_pfn_clean(pfn); @@ -2090,21 +2066,23 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu) hpa_t root = vcpu->arch.mmu.root_hpa; ASSERT(!VALID_PAGE(root)); - if (tdp_enabled) - direct = 1; if (mmu_check_root(vcpu, root_gfn)) return 1; + if (tdp_enabled) { + direct = 1; + root_gfn = 0; + } + spin_lock(&vcpu->kvm->mmu_lock); sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL, direct, ACC_ALL, NULL); root = __pa(sp->spt); ++sp->root_count; + spin_unlock(&vcpu->kvm->mmu_lock); vcpu->arch.mmu.root_hpa = root; return 0; } direct = !is_paging(vcpu); - if (tdp_enabled) - direct = 1; for (i = 0; i < 4; ++i) { hpa_t root = vcpu->arch.mmu.pae_root[i]; @@ -2120,11 +2098,18 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu) root_gfn = 0; if (mmu_check_root(vcpu, root_gfn)) return 1; + if (tdp_enabled) { + direct = 1; + root_gfn = i << 30; + } + spin_lock(&vcpu->kvm->mmu_lock); sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, PT32_ROOT_LEVEL, direct, ACC_ALL, NULL); root = __pa(sp->spt); ++sp->root_count; + spin_unlock(&vcpu->kvm->mmu_lock); + vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK; } vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root); @@ -2162,8 +2147,11 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) spin_unlock(&vcpu->kvm->mmu_lock); } -static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr) +static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr, + u32 access, u32 *error) { + if (error) + *error = 0; return vaddr; } @@ -2305,13 +2293,19 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level) /* no rsvd bits for 2 level 4K page table entries */ context->rsvd_bits_mask[0][1] = 0; context->rsvd_bits_mask[0][0] = 0; + context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; + + if (!is_pse(vcpu)) { + context->rsvd_bits_mask[1][1] = 0; + break; + } + if (is_cpuid_PSE36()) /* 36bits PSE 4MB page */ context->rsvd_bits_mask[1][1] = rsvd_bits(17, 21); else /* 32 bits PSE 4MB page */ context->rsvd_bits_mask[1][1] = rsvd_bits(13, 21); - context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0]; break; case PT32E_ROOT_LEVEL: context->rsvd_bits_mask[0][2] = @@ -2324,7 +2318,7 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level) context->rsvd_bits_mask[1][1] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 62) | rsvd_bits(13, 20); /* large page */ - context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0]; + context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; break; case PT64_ROOT_LEVEL: context->rsvd_bits_mask[0][3] = exb_bit_rsvd | @@ -2342,7 +2336,7 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level) context->rsvd_bits_mask[1][1] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 51) | rsvd_bits(13, 20); /* large page */ - context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0]; + context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; break; } } @@ -2444,7 +2438,8 @@ static int init_kvm_softmmu(struct kvm_vcpu *vcpu) else r = paging32_init_context(vcpu); - vcpu->arch.mmu.base_role.glevels = vcpu->arch.mmu.root_level; + vcpu->arch.mmu.base_role.cr4_pae = !!is_pae(vcpu); + vcpu->arch.mmu.base_role.cr0_wp = is_write_protection(vcpu); return r; } @@ -2484,7 +2479,9 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu) goto out; spin_lock(&vcpu->kvm->mmu_lock); kvm_mmu_free_some_pages(vcpu); + spin_unlock(&vcpu->kvm->mmu_lock); r = mmu_alloc_roots(vcpu); + spin_lock(&vcpu->kvm->mmu_lock); mmu_sync_roots(vcpu); spin_unlock(&vcpu->kvm->mmu_lock); if (r) @@ -2533,7 +2530,7 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, } ++vcpu->kvm->stat.mmu_pte_updated; - if (sp->role.glevels == PT32_ROOT_LEVEL) + if (!sp->role.cr4_pae) paging32_update_pte(vcpu, sp, spte, new); else paging64_update_pte(vcpu, sp, spte, new); @@ -2568,36 +2565,11 @@ static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu) } static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, - const u8 *new, int bytes) + u64 gpte) { gfn_t gfn; - int r; - u64 gpte = 0; pfn_t pfn; - if (bytes != 4 && bytes != 8) - return; - - /* - * Assume that the pte write on a page table of the same type - * as the current vcpu paging mode. This is nearly always true - * (might be false while changing modes). Note it is verified later - * by update_pte(). - */ - if (is_pae(vcpu)) { - /* Handle a 32-bit guest writing two halves of a 64-bit gpte */ - if ((bytes == 4) && (gpa % 4 == 0)) { - r = kvm_read_guest(vcpu->kvm, gpa & ~(u64)7, &gpte, 8); - if (r) - return; - memcpy((void *)&gpte + (gpa % 8), new, 4); - } else if ((bytes == 8) && (gpa % 8 == 0)) { - memcpy((void *)&gpte, new, 8); - } - } else { - if ((bytes == 4) && (gpa % 4 == 0)) - memcpy((void *)&gpte, new, 4); - } if (!is_present_gpte(gpte)) return; gfn = (gpte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT; @@ -2646,10 +2618,46 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, int flooded = 0; int npte; int r; + int invlpg_counter; pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes); - mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes); + + invlpg_counter = atomic_read(&vcpu->kvm->arch.invlpg_counter); + + /* + * Assume that the pte write on a page table of the same type + * as the current vcpu paging mode. This is nearly always true + * (might be false while changing modes). Note it is verified later + * by update_pte(). + */ + if ((is_pae(vcpu) && bytes == 4) || !new) { + /* Handle a 32-bit guest writing two halves of a 64-bit gpte */ + if (is_pae(vcpu)) { + gpa &= ~(gpa_t)7; + bytes = 8; + } + r = kvm_read_guest(vcpu->kvm, gpa, &gentry, min(bytes, 8)); + if (r) + gentry = 0; + new = (const u8 *)&gentry; + } + + switch (bytes) { + case 4: + gentry = *(const u32 *)new; + break; + case 8: + gentry = *(const u64 *)new; + break; + default: + gentry = 0; + break; + } + + mmu_guess_page_from_pte_write(vcpu, gpa, gentry); spin_lock(&vcpu->kvm->mmu_lock); + if (atomic_read(&vcpu->kvm->arch.invlpg_counter) != invlpg_counter) + gentry = 0; kvm_mmu_access_page(vcpu, gfn); kvm_mmu_free_some_pages(vcpu); ++vcpu->kvm->stat.mmu_pte_write; @@ -2668,10 +2676,12 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, } index = kvm_page_table_hashfn(gfn); bucket = &vcpu->kvm->arch.mmu_page_hash[index]; + +restart: hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) { if (sp->gfn != gfn || sp->role.direct || sp->role.invalid) continue; - pte_size = sp->role.glevels == PT32_ROOT_LEVEL ? 4 : 8; + pte_size = sp->role.cr4_pae ? 8 : 4; misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1); misaligned |= bytes < 4; if (misaligned || flooded) { @@ -2688,14 +2698,14 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, pgprintk("misaligned: gpa %llx bytes %d role %x\n", gpa, bytes, sp->role.word); if (kvm_mmu_zap_page(vcpu->kvm, sp)) - n = bucket->first; + goto restart; ++vcpu->kvm->stat.mmu_flooded; continue; } page_offset = offset; level = sp->role.level; npte = 1; - if (sp->role.glevels == PT32_ROOT_LEVEL) { + if (!sp->role.cr4_pae) { page_offset <<= 1; /* 32->64 */ /* * A 32-bit pde maps 4MB while the shadow pdes map @@ -2713,20 +2723,11 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, continue; } spte = &sp->spt[page_offset / sizeof(*spte)]; - if ((gpa & (pte_size - 1)) || (bytes < pte_size)) { - gentry = 0; - r = kvm_read_guest_atomic(vcpu->kvm, - gpa & ~(u64)(pte_size - 1), - &gentry, pte_size); - new = (const void *)&gentry; - if (r < 0) - new = NULL; - } while (npte--) { entry = *spte; mmu_pte_write_zap_pte(vcpu, sp, spte); - if (new) - mmu_pte_write_new_pte(vcpu, sp, spte, new); + if (gentry) + mmu_pte_write_new_pte(vcpu, sp, spte, &gentry); mmu_pte_write_flush_tlb(vcpu, entry, *spte); ++spte; } @@ -2747,7 +2748,7 @@ int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva) if (tdp_enabled) return 0; - gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva); + gpa = kvm_mmu_gva_to_gpa_read(vcpu, gva, NULL); spin_lock(&vcpu->kvm->mmu_lock); r = kvm_mmu_unprotect_page(vcpu->kvm, gpa >> PAGE_SHIFT); @@ -2847,16 +2848,13 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu) */ page = alloc_page(GFP_KERNEL | __GFP_DMA32); if (!page) - goto error_1; + return -ENOMEM; + vcpu->arch.mmu.pae_root = page_address(page); for (i = 0; i < 4; ++i) vcpu->arch.mmu.pae_root[i] = INVALID_PAGE; return 0; - -error_1: - free_mmu_pages(vcpu); - return -ENOMEM; } int kvm_mmu_create(struct kvm_vcpu *vcpu) @@ -2909,25 +2907,26 @@ void kvm_mmu_zap_all(struct kvm *kvm) struct kvm_mmu_page *sp, *node; spin_lock(&kvm->mmu_lock); +restart: list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link) if (kvm_mmu_zap_page(kvm, sp)) - node = container_of(kvm->arch.active_mmu_pages.next, - struct kvm_mmu_page, link); + goto restart; + spin_unlock(&kvm->mmu_lock); kvm_flush_remote_tlbs(kvm); } -static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm *kvm) +static int kvm_mmu_remove_some_alloc_mmu_pages(struct kvm *kvm) { struct kvm_mmu_page *page; page = container_of(kvm->arch.active_mmu_pages.prev, struct kvm_mmu_page, link); - kvm_mmu_zap_page(kvm, page); + return kvm_mmu_zap_page(kvm, page) + 1; } -static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask) +static int mmu_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask) { struct kvm *kvm; struct kvm *kvm_freed = NULL; @@ -2936,23 +2935,22 @@ static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask) spin_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) { - int npages; + int npages, idx, freed_pages; - if (!down_read_trylock(&kvm->slots_lock)) - continue; + idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); npages = kvm->arch.n_alloc_mmu_pages - kvm->arch.n_free_mmu_pages; cache_count += npages; if (!kvm_freed && nr_to_scan > 0 && npages > 0) { - kvm_mmu_remove_one_alloc_mmu_page(kvm); - cache_count--; + freed_pages = kvm_mmu_remove_some_alloc_mmu_pages(kvm); + cache_count -= freed_pages; kvm_freed = kvm; } nr_to_scan--; spin_unlock(&kvm->mmu_lock); - up_read(&kvm->slots_lock); + srcu_read_unlock(&kvm->srcu, idx); } if (kvm_freed) list_move_tail(&kvm_freed->vm_list, &vm_list); @@ -3019,9 +3017,12 @@ unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm) int i; unsigned int nr_mmu_pages; unsigned int nr_pages = 0; + struct kvm_memslots *slots; + + slots = kvm_memslots(kvm); - for (i = 0; i < kvm->nmemslots; i++) - nr_pages += kvm->memslots[i].npages; + for (i = 0; i < slots->nmemslots; i++) + nr_pages += slots->memslots[i].npages; nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000; nr_mmu_pages = max(nr_mmu_pages, @@ -3182,8 +3183,7 @@ static gva_t canonicalize(gva_t gva) } -typedef void (*inspect_spte_fn) (struct kvm *kvm, struct kvm_mmu_page *sp, - u64 *sptep); +typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep); static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, inspect_spte_fn fn) @@ -3199,7 +3199,7 @@ static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, child = page_header(ent & PT64_BASE_ADDR_MASK); __mmu_spte_walk(kvm, child, fn); } else - fn(kvm, sp, &sp->spt[i]); + fn(kvm, &sp->spt[i]); } } } @@ -3246,7 +3246,7 @@ static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, if (is_shadow_present_pte(ent) && !is_last_spte(ent, level)) audit_mappings_page(vcpu, ent, va, level - 1); else { - gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, va); + gpa_t gpa = kvm_mmu_gva_to_gpa_read(vcpu, va, NULL); gfn_t gfn = gpa >> PAGE_SHIFT; pfn_t pfn = gfn_to_pfn(vcpu->kvm, gfn); hpa_t hpa = (hpa_t)pfn << PAGE_SHIFT; @@ -3290,11 +3290,15 @@ static void audit_mappings(struct kvm_vcpu *vcpu) static int count_rmaps(struct kvm_vcpu *vcpu) { + struct kvm *kvm = vcpu->kvm; + struct kvm_memslots *slots; int nmaps = 0; - int i, j, k; + int i, j, k, idx; + idx = srcu_read_lock(&kvm->srcu); + slots = kvm_memslots(kvm); for (i = 0; i < KVM_MEMORY_SLOTS; ++i) { - struct kvm_memory_slot *m = &vcpu->kvm->memslots[i]; + struct kvm_memory_slot *m = &slots->memslots[i]; struct kvm_rmap_desc *d; for (j = 0; j < m->npages; ++j) { @@ -3317,10 +3321,11 @@ static int count_rmaps(struct kvm_vcpu *vcpu) } } } + srcu_read_unlock(&kvm->srcu, idx); return nmaps; } -void inspect_spte_has_rmap(struct kvm *kvm, struct kvm_mmu_page *sp, u64 *sptep) +void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) { unsigned long *rmapp; struct kvm_mmu_page *rev_sp; @@ -3336,14 +3341,14 @@ void inspect_spte_has_rmap(struct kvm *kvm, struct kvm_mmu_page *sp, u64 *sptep) printk(KERN_ERR "%s: no memslot for gfn %ld\n", audit_msg, gfn); printk(KERN_ERR "%s: index %ld of sp (gfn=%lx)\n", - audit_msg, sptep - rev_sp->spt, + audit_msg, (long int)(sptep - rev_sp->spt), rev_sp->gfn); dump_stack(); return; } rmapp = gfn_to_rmap(kvm, rev_sp->gfns[sptep - rev_sp->spt], - is_large_pte(*sptep)); + rev_sp->role.level); if (!*rmapp) { if (!printk_ratelimit()) return; @@ -3378,7 +3383,7 @@ static void check_writable_mappings_rmap(struct kvm_vcpu *vcpu) continue; if (!(ent & PT_WRITABLE_MASK)) continue; - inspect_spte_has_rmap(vcpu->kvm, sp, &pt[i]); + inspect_spte_has_rmap(vcpu->kvm, &pt[i]); } } return; |