/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * KVM/MIPS MMU handling in the KVM module. * * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved. * Authors: Sanjay Lal */ #include #include #include #include #include /* * KVM_MMU_CACHE_MIN_PAGES is the number of GPA page table translation levels * for which pages need to be cached. */ #if defined(__PAGETABLE_PMD_FOLDED) #define KVM_MMU_CACHE_MIN_PAGES 1 #else #define KVM_MMU_CACHE_MIN_PAGES 2 #endif static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, int min, int max) { void *page; BUG_ON(max > KVM_NR_MEM_OBJS); if (cache->nobjs >= min) return 0; while (cache->nobjs < max) { page = (void *)__get_free_page(GFP_KERNEL); if (!page) return -ENOMEM; cache->objects[cache->nobjs++] = page; } return 0; } static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc) { while (mc->nobjs) free_page((unsigned long)mc->objects[--mc->nobjs]); } static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc) { void *p; BUG_ON(!mc || !mc->nobjs); p = mc->objects[--mc->nobjs]; return p; } void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu) { mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); } /** * kvm_pgd_init() - Initialise KVM GPA page directory. * @page: Pointer to page directory (PGD) for KVM GPA. * * Initialise a KVM GPA page directory with pointers to the invalid table, i.e. * representing no mappings. This is similar to pgd_init(), however it * initialises all the page directory pointers, not just the ones corresponding * to the userland address space (since it is for the guest physical address * space rather than a virtual address space). */ static void kvm_pgd_init(void *page) { unsigned long *p, *end; unsigned long entry; #ifdef __PAGETABLE_PMD_FOLDED entry = (unsigned long)invalid_pte_table; #else entry = (unsigned long)invalid_pmd_table; #endif p = (unsigned long *)page; end = p + PTRS_PER_PGD; do { p[0] = entry; p[1] = entry; p[2] = entry; p[3] = entry; p[4] = entry; p += 8; p[-3] = entry; p[-2] = entry; p[-1] = entry; } while (p != end); } /** * kvm_pgd_alloc() - Allocate and initialise a KVM GPA page directory. * * Allocate a blank KVM GPA page directory (PGD) for representing guest physical * to host physical page mappings. * * Returns: Pointer to new KVM GPA page directory. * NULL on allocation failure. */ pgd_t *kvm_pgd_alloc(void) { pgd_t *ret; ret = (pgd_t *)__get_free_pages(GFP_KERNEL, PGD_ORDER); if (ret) kvm_pgd_init(ret); return ret; } /** * kvm_mips_walk_pgd() - Walk page table with optional allocation. * @pgd: Page directory pointer. * @addr: Address to index page table using. * @cache: MMU page cache to allocate new page tables from, or NULL. * * Walk the page tables pointed to by @pgd to find the PTE corresponding to the * address @addr. If page tables don't exist for @addr, they will be created * from the MMU cache if @cache is not NULL. * * Returns: Pointer to pte_t corresponding to @addr. * NULL if a page table doesn't exist for @addr and !@cache. * NULL if a page table allocation failed. */ static pte_t *kvm_mips_walk_pgd(pgd_t *pgd, struct kvm_mmu_memory_cache *cache, unsigned long addr) { pud_t *pud; pmd_t *pmd; pgd += pgd_index(addr); if (pgd_none(*pgd)) { /* Not used on MIPS yet */ BUG(); return NULL; } pud = pud_offset(pgd, addr); if (pud_none(*pud)) { pmd_t *new_pmd; if (!cache) return NULL; new_pmd = mmu_memory_cache_alloc(cache); pmd_init((unsigned long)new_pmd, (unsigned long)invalid_pte_table); pud_populate(NULL, pud, new_pmd); } pmd = pmd_offset(pud, addr); if (pmd_none(*pmd)) { pte_t *new_pte; if (!cache) return NULL; new_pte = mmu_memory_cache_alloc(cache); clear_page(new_pte); pmd_populate_kernel(NULL, pmd, new_pte); } return pte_offset(pmd, addr); } /* Caller must hold kvm->mm_lock */ static pte_t *kvm_mips_pte_for_gpa(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, unsigned long addr) { return kvm_mips_walk_pgd(kvm->arch.gpa_mm.pgd, cache, addr); } /* * kvm_mips_flush_gpa_{pte,pmd,pud,pgd,pt}. * Flush a range of guest physical address space from the VM's GPA page tables. */ static bool kvm_mips_flush_gpa_pte(pte_t *pte, unsigned long start_gpa, unsigned long end_gpa) { int i_min = __pte_offset(start_gpa); int i_max = __pte_offset(end_gpa); bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PTE - 1); int i; for (i = i_min; i <= i_max; ++i) { if (!pte_present(pte[i])) continue; kvm_release_pfn_clean(pte_pfn(pte[i])); set_pte(pte + i, __pte(0)); } return safe_to_remove; } static bool kvm_mips_flush_gpa_pmd(pmd_t *pmd, unsigned long start_gpa, unsigned long end_gpa) { pte_t *pte; unsigned long end = ~0ul; int i_min = __pmd_offset(start_gpa); int i_max = __pmd_offset(end_gpa); bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PMD - 1); int i; for (i = i_min; i <= i_max; ++i, start_gpa = 0) { if (!pmd_present(pmd[i])) continue; pte = pte_offset(pmd + i, 0); if (i == i_max) end = end_gpa; if (kvm_mips_flush_gpa_pte(pte, start_gpa, end)) { pmd_clear(pmd + i); pte_free_kernel(NULL, pte); } else { safe_to_remove = false; } } return safe_to_remove; } static bool kvm_mips_flush_gpa_pud(pud_t *pud, unsigned long start_gpa, unsigned long end_gpa) { pmd_t *pmd; unsigned long end = ~0ul; int i_min = __pud_offset(start_gpa); int i_max = __pud_offset(end_gpa); bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PUD - 1); int i; for (i = i_min; i <= i_max; ++i, start_gpa = 0) { if (!pud_present(pud[i])) continue; pmd = pmd_offset(pud + i, 0); if (i == i_max) end = end_gpa; if (kvm_mips_flush_gpa_pmd(pmd, start_gpa, end)) { pud_clear(pud + i); pmd_free(NULL, pmd); } else { safe_to_remove = false; } } return safe_to_remove; } static bool kvm_mips_flush_gpa_pgd(pgd_t *pgd, unsigned long start_gpa, unsigned long end_gpa) { pud_t *pud; unsigned long end = ~0ul; int i_min = pgd_index(start_gpa); int i_max = pgd_index(end_gpa); bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PGD - 1); int i; for (i = i_min; i <= i_max; ++i, start_gpa = 0) { if (!pgd_present(pgd[i])) continue; pud = pud_offset(pgd + i, 0); if (i == i_max) end = end_gpa; if (kvm_mips_flush_gpa_pud(pud, start_gpa, end)) { pgd_clear(pgd + i); pud_free(NULL, pud); } else { safe_to_remove = false; } } return safe_to_remove; } /** * kvm_mips_flush_gpa_pt() - Flush a range of guest physical addresses. * @kvm: KVM pointer. * @start_gfn: Guest frame number of first page in GPA range to flush. * @end_gfn: Guest frame number of last page in GPA range to flush. * * Flushes a range of GPA mappings from the GPA page tables. * * The caller must hold the @kvm->mmu_lock spinlock. * * Returns: Whether its safe to remove the top level page directory because * all lower levels have been removed. */ bool kvm_mips_flush_gpa_pt(struct kvm *kvm, gfn_t start_gfn, gfn_t end_gfn) { return kvm_mips_flush_gpa_pgd(kvm->arch.gpa_mm.pgd, start_gfn << PAGE_SHIFT, end_gfn << PAGE_SHIFT); } #define BUILD_PTE_RANGE_OP(name, op) \ static int kvm_mips_##name##_pte(pte_t *pte, unsigned long start, \ unsigned long end) \ { \ int ret = 0; \ int i_min = __pte_offset(start); \ int i_max = __pte_offset(end); \ int i; \ pte_t old, new; \ \ for (i = i_min; i <= i_max; ++i) { \ if (!pte_present(pte[i])) \ continue; \ \ old = pte[i]; \ new = op(old); \ if (pte_val(new) == pte_val(old)) \ continue; \ set_pte(pte + i, new); \ ret = 1; \ } \ return ret; \ } \ \ /* returns true if anything was done */ \ static int kvm_mips_##name##_pmd(pmd_t *pmd, unsigned long start, \ unsigned long end) \ { \ int ret = 0; \ pte_t *pte; \ unsigned long cur_end = ~0ul; \ int i_min = __pmd_offset(start); \ int i_max = __pmd_offset(end); \ int i; \ \ for (i = i_min; i <= i_max; ++i, start = 0) { \ if (!pmd_present(pmd[i])) \ continue; \ \ pte = pte_offset(pmd + i, 0); \ if (i == i_max) \ cur_end = end; \ \ ret |= kvm_mips_##name##_pte(pte, start, cur_end); \ } \ return ret; \ } \ \ static int kvm_mips_##name##_pud(pud_t *pud, unsigned long start, \ unsigned long end) \ { \ int ret = 0; \ pmd_t *pmd; \ unsigned long cur_end = ~0ul; \ int i_min = __pud_offset(start); \ int i_max = __pud_offset(end); \ int i; \ \ for (i = i_min; i <= i_max; ++i, start = 0) { \ if (!pud_present(pud[i])) \ continue; \ \ pmd = pmd_offset(pud + i, 0); \ if (i == i_max) \ cur_end = end; \ \ ret |= kvm_mips_##name##_pmd(pmd, start, cur_end); \ } \ return ret; \ } \ \ static int kvm_mips_##name##_pgd(pgd_t *pgd, unsigned long start, \ unsigned long end) \ { \ int ret = 0; \ pud_t *pud; \ unsigned long cur_end = ~0ul; \ int i_min = pgd_index(start); \ int i_max = pgd_index(end); \ int i; \ \ for (i = i_min; i <= i_max; ++i, start = 0) { \ if (!pgd_present(pgd[i])) \ continue; \ \ pud = pud_offset(pgd + i, 0); \ if (i == i_max) \ cur_end = end; \ \ ret |= kvm_mips_##name##_pud(pud, start, cur_end); \ } \ return ret; \ } /* * kvm_mips_mkclean_gpa_pt. * Mark a range of guest physical address space clean (writes fault) in the VM's * GPA page table to allow dirty page tracking. */ BUILD_PTE_RANGE_OP(mkclean, pte_mkclean) /** * kvm_mips_mkclean_gpa_pt() - Make a range of guest physical addresses clean. * @kvm: KVM pointer. * @start_gfn: Guest frame number of first page in GPA range to flush. * @end_gfn: Guest frame number of last page in GPA range to flush. * * Make a range of GPA mappings clean so that guest writes will fault and * trigger dirty page logging. * * The caller must hold the @kvm->mmu_lock spinlock. * * Returns: Whether any GPA mappings were modified, which would require * derived mappings (GVA page tables & TLB enties) to be * invalidated. */ int kvm_mips_mkclean_gpa_pt(struct kvm *kvm, gfn_t start_gfn, gfn_t end_gfn) { return kvm_mips_mkclean_pgd(kvm->arch.gpa_mm.pgd, start_gfn << PAGE_SHIFT, end_gfn << PAGE_SHIFT); } /** * kvm_mips_map_page() - Map a guest physical page. * @vcpu: VCPU pointer. * @gpa: Guest physical address of fault. * @write_fault: Whether the fault was due to a write. * @out_entry: New PTE for @gpa (written on success unless NULL). * @out_buddy: New PTE for @gpa's buddy (written on success unless * NULL). * * Handle GPA faults by creating a new GPA mapping (or updating an existing * one). * * This takes care of asking KVM for the corresponding PFN, and creating a * mapping in the GPA page tables. Derived mappings (GVA page tables and TLBs) * must be handled by the caller. * * Returns: 0 on success, in which case the caller may use the @out_entry * and @out_buddy PTEs to update derived mappings and resume guest * execution. * -EFAULT if there is no memory region at @gpa or a write was * attempted to a read-only memory region. This is usually handled * as an MMIO access. */ static int kvm_mips_map_page(struct kvm_vcpu *vcpu, unsigned long gpa, bool write_fault, pte_t *out_entry, pte_t *out_buddy) { struct kvm *kvm = vcpu->kvm; struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache; gfn_t gfn = gpa >> PAGE_SHIFT; int srcu_idx, err; kvm_pfn_t pfn; pte_t *ptep, entry, old_pte; unsigned long prot_bits; srcu_idx = srcu_read_lock(&kvm->srcu); /* We need a minimum of cached pages ready for page table creation */ err = mmu_topup_memory_cache(memcache, KVM_MMU_CACHE_MIN_PAGES, KVM_NR_MEM_OBJS); if (err) goto out; pfn = gfn_to_pfn(kvm, gfn); if (is_error_noslot_pfn(pfn)) { err = -EFAULT; goto out; } spin_lock(&kvm->mmu_lock); ptep = kvm_mips_pte_for_gpa(kvm, memcache, gpa); prot_bits = __READABLE | _PAGE_PRESENT | __WRITEABLE; entry = pfn_pte(pfn, __pgprot(prot_bits)); old_pte = *ptep; set_pte(ptep, entry); if (pte_present(old_pte)) kvm_release_pfn_clean(pte_pfn(old_pte)); err = 0; if (out_entry) *out_entry = *ptep; if (out_buddy) *out_buddy = *ptep_buddy(ptep); spin_unlock(&kvm->mmu_lock); out: srcu_read_unlock(&kvm->srcu, srcu_idx); return err; } static pte_t *kvm_trap_emul_pte_for_gva(struct kvm_vcpu *vcpu, unsigned long addr) { struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache; pgd_t *pgdp; int ret; /* We need a minimum of cached pages ready for page table creation */ ret = mmu_topup_memory_cache(memcache, KVM_MMU_CACHE_MIN_PAGES, KVM_NR_MEM_OBJS); if (ret) return NULL; if (KVM_GUEST_KERNEL_MODE(vcpu)) pgdp = vcpu->arch.guest_kernel_mm.pgd; else pgdp = vcpu->arch.guest_user_mm.pgd; return kvm_mips_walk_pgd(pgdp, memcache, addr); } void kvm_trap_emul_invalidate_gva(struct kvm_vcpu *vcpu, unsigned long addr, bool user) { pgd_t *pgdp; pte_t *ptep; addr &= PAGE_MASK << 1; pgdp = vcpu->arch.guest_kernel_mm.pgd; ptep = kvm_mips_walk_pgd(pgdp, NULL, addr); if (ptep) { ptep[0] = pfn_pte(0, __pgprot(0)); ptep[1] = pfn_pte(0, __pgprot(0)); } if (user) { pgdp = vcpu->arch.guest_user_mm.pgd; ptep = kvm_mips_walk_pgd(pgdp, NULL, addr); if (ptep) { ptep[0] = pfn_pte(0, __pgprot(0)); ptep[1] = pfn_pte(0, __pgprot(0)); } } } /* * kvm_mips_flush_gva_{pte,pmd,pud,pgd,pt}. * Flush a range of guest physical address space from the VM's GPA page tables. */ static bool kvm_mips_flush_gva_pte(pte_t *pte, unsigned long start_gva, unsigned long end_gva) { int i_min = __pte_offset(start_gva); int i_max = __pte_offset(end_gva); bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PTE - 1); int i; /* * There's no freeing to do, so there's no point clearing individual * entries unless only part of the last level page table needs flushing. */ if (safe_to_remove) return true; for (i = i_min; i <= i_max; ++i) { if (!pte_present(pte[i])) continue; set_pte(pte + i, __pte(0)); } return false; } static bool kvm_mips_flush_gva_pmd(pmd_t *pmd, unsigned long start_gva, unsigned long end_gva) { pte_t *pte; unsigned long end = ~0ul; int i_min = __pmd_offset(start_gva); int i_max = __pmd_offset(end_gva); bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PMD - 1); int i; for (i = i_min; i <= i_max; ++i, start_gva = 0) { if (!pmd_present(pmd[i])) continue; pte = pte_offset(pmd + i, 0); if (i == i_max) end = end_gva; if (kvm_mips_flush_gva_pte(pte, start_gva, end)) { pmd_clear(pmd + i); pte_free_kernel(NULL, pte); } else { safe_to_remove = false; } } return safe_to_remove; } static bool kvm_mips_flush_gva_pud(pud_t *pud, unsigned long start_gva, unsigned long end_gva) { pmd_t *pmd; unsigned long end = ~0ul; int i_min = __pud_offset(start_gva); int i_max = __pud_offset(end_gva); bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PUD - 1); int i; for (i = i_min; i <= i_max; ++i, start_gva = 0) { if (!pud_present(pud[i])) continue; pmd = pmd_offset(pud + i, 0); if (i == i_max) end = end_gva; if (kvm_mips_flush_gva_pmd(pmd, start_gva, end)) { pud_clear(pud + i); pmd_free(NULL, pmd); } else { safe_to_remove = false; } } return safe_to_remove; } static bool kvm_mips_flush_gva_pgd(pgd_t *pgd, unsigned long start_gva, unsigned long end_gva) { pud_t *pud; unsigned long end = ~0ul; int i_min = pgd_index(start_gva); int i_max = pgd_index(end_gva); bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PGD - 1); int i; for (i = i_min; i <= i_max; ++i, start_gva = 0) { if (!pgd_present(pgd[i])) continue; pud = pud_offset(pgd + i, 0); if (i == i_max) end = end_gva; if (kvm_mips_flush_gva_pud(pud, start_gva, end)) { pgd_clear(pgd + i); pud_free(NULL, pud); } else { safe_to_remove = false; } } return safe_to_remove; } void kvm_mips_flush_gva_pt(pgd_t *pgd, enum kvm_mips_flush flags) { if (flags & KMF_GPA) { /* all of guest virtual address space could be affected */ if (flags & KMF_KERN) /* useg, kseg0, seg2/3 */ kvm_mips_flush_gva_pgd(pgd, 0, 0x7fffffff); else /* useg */ kvm_mips_flush_gva_pgd(pgd, 0, 0x3fffffff); } else { /* useg */ kvm_mips_flush_gva_pgd(pgd, 0, 0x3fffffff); /* kseg2/3 */ if (flags & KMF_KERN) kvm_mips_flush_gva_pgd(pgd, 0x60000000, 0x7fffffff); } } /* XXXKYMA: Must be called with interrupts disabled */ int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr, struct kvm_vcpu *vcpu, bool write_fault) { unsigned long gpa; kvm_pfn_t pfn0, pfn1; unsigned long vaddr; pte_t pte_gpa[2], *ptep_gva; if (KVM_GUEST_KSEGX(badvaddr) != KVM_GUEST_KSEG0) { kvm_err("%s: Invalid BadVaddr: %#lx\n", __func__, badvaddr); kvm_mips_dump_host_tlbs(); return -1; } /* Find host PFNs */ gpa = KVM_GUEST_CPHYSADDR(badvaddr & (PAGE_MASK << 1)); vaddr = badvaddr & (PAGE_MASK << 1); if (kvm_mips_map_page(vcpu, gpa, write_fault, &pte_gpa[0], NULL) < 0) return -1; if (kvm_mips_map_page(vcpu, gpa | PAGE_SIZE, write_fault, &pte_gpa[1], NULL) < 0) return -1; pfn0 = pte_pfn(pte_gpa[0]); pfn1 = pte_pfn(pte_gpa[1]); /* Find GVA page table entry */ ptep_gva = kvm_trap_emul_pte_for_gva(vcpu, vaddr); if (!ptep_gva) { kvm_err("No ptep for gva %lx\n", vaddr); return -1; } /* Write host PFNs into GVA page table */ ptep_gva[0] = pte_mkyoung(pte_mkdirty(pfn_pte(pfn0, PAGE_SHARED))); ptep_gva[1] = pte_mkyoung(pte_mkdirty(pfn_pte(pfn1, PAGE_SHARED))); /* Invalidate this entry in the TLB, guest kernel ASID only */ kvm_mips_host_tlb_inv(vcpu, vaddr, false, true); return 0; } int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu, struct kvm_mips_tlb *tlb, unsigned long gva, bool write_fault) { kvm_pfn_t pfn; long tlb_lo = 0; pte_t pte_gpa, *ptep_gva; unsigned int idx; bool kernel = KVM_GUEST_KERNEL_MODE(vcpu); /* * The commpage address must not be mapped to anything else if the guest * TLB contains entries nearby, or commpage accesses will break. */ idx = TLB_LO_IDX(*tlb, gva); if ((gva ^ KVM_GUEST_COMMPAGE_ADDR) & VPN2_MASK & PAGE_MASK) tlb_lo = tlb->tlb_lo[idx]; /* Find host PFN */ if (kvm_mips_map_page(vcpu, mips3_tlbpfn_to_paddr(tlb_lo), write_fault, &pte_gpa, NULL) < 0) return -1; pfn = pte_pfn(pte_gpa); /* Find GVA page table entry */ ptep_gva = kvm_trap_emul_pte_for_gva(vcpu, gva); if (!ptep_gva) { kvm_err("No ptep for gva %lx\n", gva); return -1; } /* Write PFN into GVA page table, taking attributes from Guest TLB */ *ptep_gva = pfn_pte(pfn, (!(tlb_lo & ENTRYLO_V)) ? __pgprot(0) : (tlb_lo & ENTRYLO_D) ? PAGE_SHARED : PAGE_READONLY); if (pte_present(*ptep_gva)) *ptep_gva = pte_mkyoung(pte_mkdirty(*ptep_gva)); /* Invalidate this entry in the TLB, current guest mode ASID only */ kvm_mips_host_tlb_inv(vcpu, gva, !kernel, kernel); kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc, tlb->tlb_lo[0], tlb->tlb_lo[1]); return 0; } int kvm_mips_handle_commpage_tlb_fault(unsigned long badvaddr, struct kvm_vcpu *vcpu) { kvm_pfn_t pfn; pte_t *ptep; ptep = kvm_trap_emul_pte_for_gva(vcpu, badvaddr); if (!ptep) { kvm_err("No ptep for commpage %lx\n", badvaddr); return -1; } pfn = PFN_DOWN(virt_to_phys(vcpu->arch.kseg0_commpage)); /* Also set valid and dirty, so refill handler doesn't have to */ *ptep = pte_mkyoung(pte_mkdirty(pfn_pte(pfn, PAGE_SHARED))); /* Invalidate this entry in the TLB, guest kernel ASID only */ kvm_mips_host_tlb_inv(vcpu, badvaddr, false, true); return 0; } /** * kvm_mips_migrate_count() - Migrate timer. * @vcpu: Virtual CPU. * * Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it * if it was running prior to being cancelled. * * Must be called when the VCPU is migrated to a different CPU to ensure that * timer expiry during guest execution interrupts the guest and causes the * interrupt to be delivered in a timely manner. */ static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu) { if (hrtimer_cancel(&vcpu->arch.comparecount_timer)) hrtimer_restart(&vcpu->arch.comparecount_timer); } /* Restore ASID once we are scheduled back after preemption */ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { unsigned long flags; kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu); local_irq_save(flags); vcpu->cpu = cpu; if (vcpu->arch.last_sched_cpu != cpu) { kvm_debug("[%d->%d]KVM VCPU[%d] switch\n", vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id); /* * Migrate the timer interrupt to the current CPU so that it * always interrupts the guest and synchronously triggers a * guest timer interrupt. */ kvm_mips_migrate_count(vcpu); } /* restore guest state to registers */ kvm_mips_callbacks->vcpu_load(vcpu, cpu); local_irq_restore(flags); } /* ASID can change if another task is scheduled during preemption */ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) { unsigned long flags; int cpu; local_irq_save(flags); cpu = smp_processor_id(); vcpu->arch.last_sched_cpu = cpu; vcpu->cpu = -1; /* save guest state in registers */ kvm_mips_callbacks->vcpu_put(vcpu, cpu); local_irq_restore(flags); } /** * kvm_trap_emul_gva_fault() - Safely attempt to handle a GVA access fault. * @vcpu: Virtual CPU. * @gva: Guest virtual address to be accessed. * @write: True if write attempted (must be dirtied and made writable). * * Safely attempt to handle a GVA fault, mapping GVA pages if necessary, and * dirtying the page if @write so that guest instructions can be modified. * * Returns: KVM_MIPS_MAPPED on success. * KVM_MIPS_GVA if bad guest virtual address. * KVM_MIPS_GPA if bad guest physical address. * KVM_MIPS_TLB if guest TLB not present. * KVM_MIPS_TLBINV if guest TLB present but not valid. * KVM_MIPS_TLBMOD if guest TLB read only. */ enum kvm_mips_fault_result kvm_trap_emul_gva_fault(struct kvm_vcpu *vcpu, unsigned long gva, bool write) { struct mips_coproc *cop0 = vcpu->arch.cop0; struct kvm_mips_tlb *tlb; int index; if (KVM_GUEST_KSEGX(gva) == KVM_GUEST_KSEG0) { if (kvm_mips_handle_kseg0_tlb_fault(gva, vcpu, write) < 0) return KVM_MIPS_GPA; } else if ((KVM_GUEST_KSEGX(gva) < KVM_GUEST_KSEG0) || KVM_GUEST_KSEGX(gva) == KVM_GUEST_KSEG23) { /* Address should be in the guest TLB */ index = kvm_mips_guest_tlb_lookup(vcpu, (gva & VPN2_MASK) | (kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID)); if (index < 0) return KVM_MIPS_TLB; tlb = &vcpu->arch.guest_tlb[index]; /* Entry should be valid, and dirty for writes */ if (!TLB_IS_VALID(*tlb, gva)) return KVM_MIPS_TLBINV; if (write && !TLB_IS_DIRTY(*tlb, gva)) return KVM_MIPS_TLBMOD; if (kvm_mips_handle_mapped_seg_tlb_fault(vcpu, tlb, gva, write)) return KVM_MIPS_GPA; } else { return KVM_MIPS_GVA; } return KVM_MIPS_MAPPED; } int kvm_get_inst(u32 *opc, struct kvm_vcpu *vcpu, u32 *out) { int err; retry: kvm_trap_emul_gva_lockless_begin(vcpu); err = get_user(*out, opc); kvm_trap_emul_gva_lockless_end(vcpu); if (unlikely(err)) { /* * Try to handle the fault, maybe we just raced with a GVA * invalidation. */ err = kvm_trap_emul_gva_fault(vcpu, (unsigned long)opc, false); if (unlikely(err)) { kvm_err("%s: illegal address: %p\n", __func__, opc); return -EFAULT; } /* Hopefully it'll work now */ goto retry; } return 0; }