KVM: MMU: update invlpg handler comment
[safe/jmp/linux-2.6] / arch / x86 / kvm / paging_tmpl.h
index eae9499..a601713 100644 (file)
@@ -27,7 +27,8 @@
        #define guest_walker guest_walker64
        #define FNAME(name) paging##64_##name
        #define PT_BASE_ADDR_MASK PT64_BASE_ADDR_MASK
-       #define PT_DIR_BASE_ADDR_MASK PT64_DIR_BASE_ADDR_MASK
+       #define PT_LVL_ADDR_MASK(lvl) PT64_LVL_ADDR_MASK(lvl)
+       #define PT_LVL_OFFSET_MASK(lvl) PT64_LVL_OFFSET_MASK(lvl)
        #define PT_INDEX(addr, level) PT64_INDEX(addr, level)
        #define PT_LEVEL_MASK(level) PT64_LEVEL_MASK(level)
        #define PT_LEVEL_BITS PT64_LEVEL_BITS
@@ -43,7 +44,8 @@
        #define guest_walker guest_walker32
        #define FNAME(name) paging##32_##name
        #define PT_BASE_ADDR_MASK PT32_BASE_ADDR_MASK
-       #define PT_DIR_BASE_ADDR_MASK PT32_DIR_BASE_ADDR_MASK
+       #define PT_LVL_ADDR_MASK(lvl) PT32_LVL_ADDR_MASK(lvl)
+       #define PT_LVL_OFFSET_MASK(lvl) PT32_LVL_OFFSET_MASK(lvl)
        #define PT_INDEX(addr, level) PT32_INDEX(addr, level)
        #define PT_LEVEL_MASK(level) PT32_LEVEL_MASK(level)
        #define PT_LEVEL_BITS PT32_LEVEL_BITS
@@ -53,8 +55,8 @@
        #error Invalid PTTYPE value
 #endif
 
-#define gpte_to_gfn FNAME(gpte_to_gfn)
-#define gpte_to_gfn_pde FNAME(gpte_to_gfn_pde)
+#define gpte_to_gfn_lvl FNAME(gpte_to_gfn_lvl)
+#define gpte_to_gfn(pte) gpte_to_gfn_lvl((pte), PT_PAGE_TABLE_LEVEL)
 
 /*
  * The guest_walker structure emulates the behavior of the hardware page
@@ -71,14 +73,9 @@ struct guest_walker {
        u32 error_code;
 };
 
-static gfn_t gpte_to_gfn(pt_element_t gpte)
+static gfn_t gpte_to_gfn_lvl(pt_element_t gpte, int lvl)
 {
-       return (gpte & PT_BASE_ADDR_MASK) >> PAGE_SHIFT;
-}
-
-static gfn_t gpte_to_gfn_pde(pt_element_t gpte)
-{
-       return (gpte & PT_DIR_BASE_ADDR_MASK) >> PAGE_SHIFT;
+       return (gpte & PT_LVL_ADDR_MASK(lvl)) >> PAGE_SHIFT;
 }
 
 static bool FNAME(cmpxchg_gpte)(struct kvm *kvm,
@@ -123,15 +120,18 @@ static int FNAME(walk_addr)(struct guest_walker *walker,
        gfn_t table_gfn;
        unsigned index, pt_access, pte_access;
        gpa_t pte_gpa;
+       int rsvd_fault = 0;
 
-       pgprintk("%s: addr %lx\n", __func__, addr);
+       trace_kvm_mmu_pagetable_walk(addr, write_fault, user_fault,
+                                    fetch_fault);
 walk:
        walker->level = vcpu->arch.mmu.root_level;
        pte = vcpu->arch.cr3;
 #if PTTYPE == 64
        if (!is_long_mode(vcpu)) {
-               pte = vcpu->arch.pdptrs[(addr >> 30) & 3];
-               if (!is_present_pte(pte))
+               pte = kvm_pdptr_read(vcpu, (addr >> 30) & 3);
+               trace_kvm_mmu_paging_element(pte, walker->level);
+               if (!is_present_gpte(pte))
                        goto not_present;
                --walker->level;
        }
@@ -149,14 +149,17 @@ walk:
                pte_gpa += index * sizeof(pt_element_t);
                walker->table_gfn[walker->level - 1] = table_gfn;
                walker->pte_gpa[walker->level - 1] = pte_gpa;
-               pgprintk("%s: table_gfn[%d] %lx\n", __func__,
-                        walker->level - 1, table_gfn);
 
                kvm_read_guest(vcpu->kvm, pte_gpa, &pte, sizeof(pte));
+               trace_kvm_mmu_paging_element(pte, walker->level);
 
-               if (!is_present_pte(pte))
+               if (!is_present_gpte(pte))
                        goto not_present;
 
+               rsvd_fault = is_rsvd_bits_set(vcpu, pte, walker->level);
+               if (rsvd_fault)
+                       goto access_error;
+
                if (write_fault && !is_writeble_pte(pte))
                        if (user_fault || is_write_protection(vcpu))
                                goto access_error;
@@ -170,6 +173,8 @@ walk:
 #endif
 
                if (!(pte & PT_ACCESSED_MASK)) {
+                       trace_kvm_mmu_set_accessed_bit(table_gfn, index,
+                                                      sizeof(pte));
                        mark_page_dirty(vcpu->kvm, table_gfn);
                        if (FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn,
                            index, pte, pte|PT_ACCESSED_MASK))
@@ -181,18 +186,24 @@ walk:
 
                walker->ptes[walker->level - 1] = pte;
 
-               if (walker->level == PT_PAGE_TABLE_LEVEL) {
-                       walker->gfn = gpte_to_gfn(pte);
-                       break;
-               }
-
-               if (walker->level == PT_DIRECTORY_LEVEL
-                   && (pte & PT_PAGE_SIZE_MASK)
-                   && (PTTYPE == 64 || is_pse(vcpu))) {
-                       walker->gfn = gpte_to_gfn_pde(pte);
-                       walker->gfn += PT_INDEX(addr, PT_PAGE_TABLE_LEVEL);
-                       if (PTTYPE == 32 && is_cpuid_PSE36())
+               if ((walker->level == PT_PAGE_TABLE_LEVEL) ||
+                   ((walker->level == PT_DIRECTORY_LEVEL) &&
+                               (pte & PT_PAGE_SIZE_MASK)  &&
+                               (PTTYPE == 64 || is_pse(vcpu))) ||
+                   ((walker->level == PT_PDPE_LEVEL) &&
+                               (pte & PT_PAGE_SIZE_MASK)  &&
+                               is_long_mode(vcpu))) {
+                       int lvl = walker->level;
+
+                       walker->gfn = gpte_to_gfn_lvl(pte, lvl);
+                       walker->gfn += (addr & PT_LVL_OFFSET_MASK(lvl))
+                                       >> PAGE_SHIFT;
+
+                       if (PTTYPE == 32 &&
+                           walker->level == PT_DIRECTORY_LEVEL &&
+                           is_cpuid_PSE36())
                                walker->gfn += pse36_gfn_delta(pte);
+
                        break;
                }
 
@@ -200,9 +211,10 @@ walk:
                --walker->level;
        }
 
-       if (write_fault && !is_dirty_pte(pte)) {
+       if (write_fault && !is_dirty_gpte(pte)) {
                bool ret;
 
+               trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte));
                mark_page_dirty(vcpu->kvm, table_gfn);
                ret = FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn, index, pte,
                            pte|PT_DIRTY_MASK);
@@ -232,6 +244,9 @@ err:
                walker->error_code |= PFERR_USER_MASK;
        if (fetch_fault)
                walker->error_code |= PFERR_FETCH_MASK;
+       if (rsvd_fault)
+               walker->error_code |= PFERR_RSVD_MASK;
+       trace_kvm_mmu_walker_error(walker->error_code);
        return 0;
 }
 
@@ -241,12 +256,11 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
        pt_element_t gpte;
        unsigned pte_access;
        pfn_t pfn;
-       int largepage = vcpu->arch.update_pte.largepage;
 
        gpte = *(const pt_element_t *)pte;
        if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) {
-               if (!is_present_pte(gpte))
-                       set_shadow_pte(spte, shadow_notrap_nonpresent_pte);
+               if (!is_present_gpte(gpte))
+                       __set_spte(spte, shadow_notrap_nonpresent_pte);
                return;
        }
        pgprintk("%s: gpte %llx spte %p\n", __func__, (u64)gpte, spte);
@@ -259,10 +273,13 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
        if (mmu_notifier_retry(vcpu, vcpu->arch.update_pte.mmu_seq))
                return;
        kvm_get_pfn(pfn);
+       /*
+        * we call mmu_set_spte() with reset_host_protection = true beacuse that
+        * vcpu->arch.update_pte.pfn was fetched from get_user_pages(write = 1).
+        */
        mmu_set_spte(vcpu, spte, page->role.access, pte_access, 0, 0,
-                    gpte & PT_DIRTY_MASK, NULL, largepage,
-                    gpte & PT_GLOBAL_MASK, gpte_to_gfn(gpte),
-                    pfn, true);
+                    gpte & PT_DIRTY_MASK, NULL, PT_PAGE_TABLE_LEVEL,
+                    gpte_to_gfn(gpte), pfn, true, true);
 }
 
 /*
@@ -270,12 +287,12 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
  */
 static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
                         struct guest_walker *gw,
-                        int user_fault, int write_fault, int largepage,
+                        int user_fault, int write_fault, int hlevel,
                         int *ptwrite, pfn_t pfn)
 {
        unsigned access = gw->pt_access;
        struct kvm_mmu_page *shadow_page;
-       u64 spte, *sptep;
+       u64 spte, *sptep = NULL;
        int direct;
        gfn_t table_gfn;
        int r;
@@ -283,21 +300,19 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
        pt_element_t curr_pte;
        struct kvm_shadow_walk_iterator iterator;
 
-       if (!is_present_pte(gw->ptes[gw->level - 1]))
+       if (!is_present_gpte(gw->ptes[gw->level - 1]))
                return NULL;
 
        for_each_shadow_entry(vcpu, addr, iterator) {
                level = iterator.level;
                sptep = iterator.sptep;
-               if (level == PT_PAGE_TABLE_LEVEL
-                   || (largepage && level == PT_DIRECTORY_LEVEL)) {
+               if (iterator.level == hlevel) {
                        mmu_set_spte(vcpu, sptep, access,
                                     gw->pte_access & access,
                                     user_fault, write_fault,
                                     gw->ptes[gw->level-1] & PT_DIRTY_MASK,
-                                    ptwrite, largepage,
-                                    gw->ptes[gw->level-1] & PT_GLOBAL_MASK,
-                                    gw->gfn, pfn, false);
+                                    ptwrite, level,
+                                    gw->gfn, pfn, false, true);
                        break;
                }
 
@@ -306,16 +321,19 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 
                if (is_large_pte(*sptep)) {
                        rmap_remove(vcpu->kvm, sptep);
-                       set_shadow_pte(sptep, shadow_trap_nonpresent_pte);
+                       __set_spte(sptep, shadow_trap_nonpresent_pte);
                        kvm_flush_remote_tlbs(vcpu->kvm);
                }
 
-               if (level == PT_DIRECTORY_LEVEL
-                   && gw->level == PT_DIRECTORY_LEVEL) {
+               if (level <= gw->level) {
+                       int delta = level - gw->level + 1;
                        direct = 1;
-                       if (!is_dirty_pte(gw->ptes[level - 1]))
+                       if (!is_dirty_gpte(gw->ptes[level - delta]))
                                access &= ~ACC_WRITE_MASK;
-                       table_gfn = gpte_to_gfn(gw->ptes[level - 1]);
+                       table_gfn = gpte_to_gfn(gw->ptes[level - delta]);
+                       /* advance table_gfn when emulating 1gb pages with 4k */
+                       if (delta == 0)
+                               table_gfn += PT_INDEX(addr, level);
                } else {
                        direct = 0;
                        table_gfn = gw->table_gfn[level - 2];
@@ -364,11 +382,11 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
        int user_fault = error_code & PFERR_USER_MASK;
        int fetch_fault = error_code & PFERR_FETCH_MASK;
        struct guest_walker walker;
-       u64 *shadow_pte;
+       u64 *sptep;
        int write_pt = 0;
        int r;
        pfn_t pfn;
-       int largepage = 0;
+       int level = PT_PAGE_TABLE_LEVEL;
        unsigned long mmu_seq;
 
        pgprintk("%s: addr %lx err %x\n", __func__, addr, error_code);
@@ -394,14 +412,11 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
                return 0;
        }
 
-       if (walker.level == PT_DIRECTORY_LEVEL) {
-               gfn_t large_gfn;
-               large_gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE-1);
-               if (is_largepage_backed(vcpu, large_gfn)) {
-                       walker.gfn = large_gfn;
-                       largepage = 1;
-               }
+       if (walker.level >= PT_DIRECTORY_LEVEL) {
+               level = min(walker.level, mapping_level(vcpu, walker.gfn));
+               walker.gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1);
        }
+
        mmu_seq = vcpu->kvm->mmu_notifier_seq;
        smp_rmb();
        pfn = gfn_to_pfn(vcpu->kvm, walker.gfn);
@@ -417,11 +432,10 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
        if (mmu_notifier_retry(vcpu, mmu_seq))
                goto out_unlock;
        kvm_mmu_free_some_pages(vcpu);
-       shadow_pte = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault,
-                                 largepage, &write_pt, pfn);
-
+       sptep = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault,
+                            level, &write_pt, pfn);
        pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __func__,
-                shadow_pte, *shadow_pte, write_pt);
+                sptep, *sptep, write_pt);
 
        if (!write_pt)
                vcpu->arch.last_pt_write_count = 0; /* reset fork detector */
@@ -453,9 +467,9 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
                level = iterator.level;
                sptep = iterator.sptep;
 
-               /* FIXME: properly handle invlpg on large guest pages */
-               if (level == PT_PAGE_TABLE_LEVEL ||
-                   ((level == PT_DIRECTORY_LEVEL) && is_large_pte(*sptep))) {
+               if (level == PT_PAGE_TABLE_LEVEL  ||
+                   ((level == PT_DIRECTORY_LEVEL && is_large_pte(*sptep))) ||
+                   ((level == PT_PDPE_LEVEL && is_large_pte(*sptep)))) {
                        struct kvm_mmu_page *sp = page_header(__pa(sptep));
 
                        pte_gpa = (sp->gfn << PAGE_SHIFT);
@@ -467,7 +481,7 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
                                        --vcpu->kvm->stat.lpages;
                                need_flush = 1;
                        }
-                       set_shadow_pte(sptep, shadow_trap_nonpresent_pte);
+                       __set_spte(sptep, shadow_trap_nonpresent_pte);
                        break;
                }
 
@@ -484,7 +498,7 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
        if (kvm_read_guest_atomic(vcpu->kvm, pte_gpa, &gpte,
                                  sizeof(pt_element_t)))
                return;
-       if (is_present_pte(gpte) && (gpte & PT_ACCESSED_MASK)) {
+       if (is_present_gpte(gpte) && (gpte & PT_ACCESSED_MASK)) {
                if (mmu_topup_memory_caches(vcpu))
                        return;
                kvm_mmu_pte_write(vcpu, pte_gpa, (const u8 *)&gpte,
@@ -531,7 +545,7 @@ static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
                r = kvm_read_guest_atomic(vcpu->kvm, pte_gpa, pt, sizeof pt);
                pte_gpa += ARRAY_SIZE(pt) * sizeof(pt_element_t);
                for (j = 0; j < ARRAY_SIZE(pt); ++j)
-                       if (r || is_present_pte(pt[j]))
+                       if (r || is_present_gpte(pt[j]))
                                sp->spt[i+j] = shadow_trap_nonpresent_pte;
                        else
                                sp->spt[i+j] = shadow_notrap_nonpresent_pte;
@@ -547,6 +561,7 @@ static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
 static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
 {
        int i, offset, nr_present;
+       bool reset_host_protection;
 
        offset = nr_present = 0;
 
@@ -569,24 +584,31 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
                                          sizeof(pt_element_t)))
                        return -EINVAL;
 
-               if (gpte_to_gfn(gpte) != gfn || !is_present_pte(gpte) ||
+               if (gpte_to_gfn(gpte) != gfn || !is_present_gpte(gpte) ||
                    !(gpte & PT_ACCESSED_MASK)) {
                        u64 nonpresent;
 
                        rmap_remove(vcpu->kvm, &sp->spt[i]);
-                       if (is_present_pte(gpte))
+                       if (is_present_gpte(gpte))
                                nonpresent = shadow_trap_nonpresent_pte;
                        else
                                nonpresent = shadow_notrap_nonpresent_pte;
-                       set_shadow_pte(&sp->spt[i], nonpresent);
+                       __set_spte(&sp->spt[i], nonpresent);
                        continue;
                }
 
                nr_present++;
                pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
+               if (!(sp->spt[i] & SPTE_HOST_WRITEABLE)) {
+                       pte_access &= ~ACC_WRITE_MASK;
+                       reset_host_protection = 0;
+               } else {
+                       reset_host_protection = 1;
+               }
                set_spte(vcpu, &sp->spt[i], pte_access, 0, 0,
-                        is_dirty_pte(gpte), 0, gpte & PT_GLOBAL_MASK, gfn,
-                        spte_to_pfn(sp->spt[i]), true, false);
+                        is_dirty_gpte(gpte), PT_PAGE_TABLE_LEVEL, gfn,
+                        spte_to_pfn(sp->spt[i]), true, false,
+                        reset_host_protection);
        }
 
        return !nr_present;
@@ -598,9 +620,10 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
 #undef PT_BASE_ADDR_MASK
 #undef PT_INDEX
 #undef PT_LEVEL_MASK
-#undef PT_DIR_BASE_ADDR_MASK
+#undef PT_LVL_ADDR_MASK
+#undef PT_LVL_OFFSET_MASK
 #undef PT_LEVEL_BITS
 #undef PT_MAX_FULL_LEVELS
 #undef gpte_to_gfn
-#undef gpte_to_gfn_pde
+#undef gpte_to_gfn_lvl
 #undef CMPXCHG