diff options
Diffstat (limited to 'virt/kvm/arm/mmu.c')
| -rw-r--r-- | virt/kvm/arm/mmu.c | 2447 |
1 files changed, 0 insertions, 2447 deletions
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c deleted file mode 100644 index e3b9ee268823..000000000000 --- a/virt/kvm/arm/mmu.c +++ /dev/null @@ -1,2447 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (C) 2012 - Virtual Open Systems and Columbia University - * Author: Christoffer Dall <c.dall@virtualopensystems.com> - */ - -#include <linux/mman.h> -#include <linux/kvm_host.h> -#include <linux/io.h> -#include <linux/hugetlb.h> -#include <linux/sched/signal.h> -#include <trace/events/kvm.h> -#include <asm/pgalloc.h> -#include <asm/cacheflush.h> -#include <asm/kvm_arm.h> -#include <asm/kvm_mmu.h> -#include <asm/kvm_ras.h> -#include <asm/kvm_asm.h> -#include <asm/kvm_emulate.h> -#include <asm/virt.h> - -#include "trace.h" - -static pgd_t *boot_hyp_pgd; -static pgd_t *hyp_pgd; -static pgd_t *merged_hyp_pgd; -static DEFINE_MUTEX(kvm_hyp_pgd_mutex); - -static unsigned long hyp_idmap_start; -static unsigned long hyp_idmap_end; -static phys_addr_t hyp_idmap_vector; - -static unsigned long io_map_base; - -#define hyp_pgd_order get_order(PTRS_PER_PGD * sizeof(pgd_t)) - -#define KVM_S2PTE_FLAG_IS_IOMAP (1UL << 0) -#define KVM_S2_FLAG_LOGGING_ACTIVE (1UL << 1) - -static bool is_iomap(unsigned long flags) -{ - return flags & KVM_S2PTE_FLAG_IS_IOMAP; -} - -static bool memslot_is_logging(struct kvm_memory_slot *memslot) -{ - return memslot->dirty_bitmap && !(memslot->flags & KVM_MEM_READONLY); -} - -/** - * kvm_flush_remote_tlbs() - flush all VM TLB entries for v7/8 - * @kvm: pointer to kvm structure. - * - * Interface to HYP function to flush all VM TLB entries - */ -void kvm_flush_remote_tlbs(struct kvm *kvm) -{ - kvm_call_hyp(__kvm_tlb_flush_vmid, kvm); -} - -static void kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) -{ - kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, kvm, ipa); -} - -/* - * D-Cache management functions. They take the page table entries by - * value, as they are flushing the cache using the kernel mapping (or - * kmap on 32bit). - */ -static void kvm_flush_dcache_pte(pte_t pte) -{ - __kvm_flush_dcache_pte(pte); -} - -static void kvm_flush_dcache_pmd(pmd_t pmd) -{ - __kvm_flush_dcache_pmd(pmd); -} - -static void kvm_flush_dcache_pud(pud_t pud) -{ - __kvm_flush_dcache_pud(pud); -} - -static bool kvm_is_device_pfn(unsigned long pfn) -{ - return !pfn_valid(pfn); -} - -/** - * stage2_dissolve_pmd() - clear and flush huge PMD entry - * @kvm: pointer to kvm structure. - * @addr: IPA - * @pmd: pmd pointer for IPA - * - * Function clears a PMD entry, flushes addr 1st and 2nd stage TLBs. - */ -static void stage2_dissolve_pmd(struct kvm *kvm, phys_addr_t addr, pmd_t *pmd) -{ - if (!pmd_thp_or_huge(*pmd)) - return; - - pmd_clear(pmd); - kvm_tlb_flush_vmid_ipa(kvm, addr); - put_page(virt_to_page(pmd)); -} - -/** - * stage2_dissolve_pud() - clear and flush huge PUD entry - * @kvm: pointer to kvm structure. - * @addr: IPA - * @pud: pud pointer for IPA - * - * Function clears a PUD entry, flushes addr 1st and 2nd stage TLBs. - */ -static void stage2_dissolve_pud(struct kvm *kvm, phys_addr_t addr, pud_t *pudp) -{ - if (!stage2_pud_huge(kvm, *pudp)) - return; - - stage2_pud_clear(kvm, pudp); - kvm_tlb_flush_vmid_ipa(kvm, addr); - put_page(virt_to_page(pudp)); -} - -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_PGTABLE_USER); - 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; -} - -static void clear_stage2_pgd_entry(struct kvm *kvm, pgd_t *pgd, phys_addr_t addr) -{ - pud_t *pud_table __maybe_unused = stage2_pud_offset(kvm, pgd, 0UL); - stage2_pgd_clear(kvm, pgd); - kvm_tlb_flush_vmid_ipa(kvm, addr); - stage2_pud_free(kvm, pud_table); - put_page(virt_to_page(pgd)); -} - -static void clear_stage2_pud_entry(struct kvm *kvm, pud_t *pud, phys_addr_t addr) -{ - pmd_t *pmd_table __maybe_unused = stage2_pmd_offset(kvm, pud, 0); - VM_BUG_ON(stage2_pud_huge(kvm, *pud)); - stage2_pud_clear(kvm, pud); - kvm_tlb_flush_vmid_ipa(kvm, addr); - stage2_pmd_free(kvm, pmd_table); - put_page(virt_to_page(pud)); -} - -static void clear_stage2_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr) -{ - pte_t *pte_table = pte_offset_kernel(pmd, 0); - VM_BUG_ON(pmd_thp_or_huge(*pmd)); - pmd_clear(pmd); - kvm_tlb_flush_vmid_ipa(kvm, addr); - free_page((unsigned long)pte_table); - put_page(virt_to_page(pmd)); -} - -static inline void kvm_set_pte(pte_t *ptep, pte_t new_pte) -{ - WRITE_ONCE(*ptep, new_pte); - dsb(ishst); -} - -static inline void kvm_set_pmd(pmd_t *pmdp, pmd_t new_pmd) -{ - WRITE_ONCE(*pmdp, new_pmd); - dsb(ishst); -} - -static inline void kvm_pmd_populate(pmd_t *pmdp, pte_t *ptep) -{ - kvm_set_pmd(pmdp, kvm_mk_pmd(ptep)); -} - -static inline void kvm_pud_populate(pud_t *pudp, pmd_t *pmdp) -{ - WRITE_ONCE(*pudp, kvm_mk_pud(pmdp)); - dsb(ishst); -} - -static inline void kvm_pgd_populate(pgd_t *pgdp, pud_t *pudp) -{ - WRITE_ONCE(*pgdp, kvm_mk_pgd(pudp)); - dsb(ishst); -} - -/* - * Unmapping vs dcache management: - * - * If a guest maps certain memory pages as uncached, all writes will - * bypass the data cache and go directly to RAM. However, the CPUs - * can still speculate reads (not writes) and fill cache lines with - * data. - * - * Those cache lines will be *clean* cache lines though, so a - * clean+invalidate operation is equivalent to an invalidate - * operation, because no cache lines are marked dirty. - * - * Those clean cache lines could be filled prior to an uncached write - * by the guest, and the cache coherent IO subsystem would therefore - * end up writing old data to disk. - * - * This is why right after unmapping a page/section and invalidating - * the corresponding TLBs, we call kvm_flush_dcache_p*() to make sure - * the IO subsystem will never hit in the cache. - * - * This is all avoided on systems that have ARM64_HAS_STAGE2_FWB, as - * we then fully enforce cacheability of RAM, no matter what the guest - * does. - */ -static void unmap_stage2_ptes(struct kvm *kvm, pmd_t *pmd, - phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t start_addr = addr; - pte_t *pte, *start_pte; - - start_pte = pte = pte_offset_kernel(pmd, addr); - do { - if (!pte_none(*pte)) { - pte_t old_pte = *pte; - - kvm_set_pte(pte, __pte(0)); - kvm_tlb_flush_vmid_ipa(kvm, addr); - - /* No need to invalidate the cache for device mappings */ - if (!kvm_is_device_pfn(pte_pfn(old_pte))) - kvm_flush_dcache_pte(old_pte); - - put_page(virt_to_page(pte)); - } - } while (pte++, addr += PAGE_SIZE, addr != end); - - if (stage2_pte_table_empty(kvm, start_pte)) - clear_stage2_pmd_entry(kvm, pmd, start_addr); -} - -static void unmap_stage2_pmds(struct kvm *kvm, pud_t *pud, - phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t next, start_addr = addr; - pmd_t *pmd, *start_pmd; - - start_pmd = pmd = stage2_pmd_offset(kvm, pud, addr); - do { - next = stage2_pmd_addr_end(kvm, addr, end); - if (!pmd_none(*pmd)) { - if (pmd_thp_or_huge(*pmd)) { - pmd_t old_pmd = *pmd; - - pmd_clear(pmd); - kvm_tlb_flush_vmid_ipa(kvm, addr); - - kvm_flush_dcache_pmd(old_pmd); - - put_page(virt_to_page(pmd)); - } else { - unmap_stage2_ptes(kvm, pmd, addr, next); - } - } - } while (pmd++, addr = next, addr != end); - - if (stage2_pmd_table_empty(kvm, start_pmd)) - clear_stage2_pud_entry(kvm, pud, start_addr); -} - -static void unmap_stage2_puds(struct kvm *kvm, pgd_t *pgd, - phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t next, start_addr = addr; - pud_t *pud, *start_pud; - - start_pud = pud = stage2_pud_offset(kvm, pgd, addr); - do { - next = stage2_pud_addr_end(kvm, addr, end); - if (!stage2_pud_none(kvm, *pud)) { - if (stage2_pud_huge(kvm, *pud)) { - pud_t old_pud = *pud; - - stage2_pud_clear(kvm, pud); - kvm_tlb_flush_vmid_ipa(kvm, addr); - kvm_flush_dcache_pud(old_pud); - put_page(virt_to_page(pud)); - } else { - unmap_stage2_pmds(kvm, pud, addr, next); - } - } - } while (pud++, addr = next, addr != end); - - if (stage2_pud_table_empty(kvm, start_pud)) - clear_stage2_pgd_entry(kvm, pgd, start_addr); -} - -/** - * unmap_stage2_range -- Clear stage2 page table entries to unmap a range - * @kvm: The VM pointer - * @start: The intermediate physical base address of the range to unmap - * @size: The size of the area to unmap - * - * Clear a range of stage-2 mappings, lowering the various ref-counts. Must - * be called while holding mmu_lock (unless for freeing the stage2 pgd before - * destroying the VM), otherwise another faulting VCPU may come in and mess - * with things behind our backs. - */ -static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size) -{ - pgd_t *pgd; - phys_addr_t addr = start, end = start + size; - phys_addr_t next; - - assert_spin_locked(&kvm->mmu_lock); - WARN_ON(size & ~PAGE_MASK); - - pgd = kvm->arch.pgd + stage2_pgd_index(kvm, addr); - do { - /* - * Make sure the page table is still active, as another thread - * could have possibly freed the page table, while we released - * the lock. - */ - if (!READ_ONCE(kvm->arch.pgd)) - break; - next = stage2_pgd_addr_end(kvm, addr, end); - if (!stage2_pgd_none(kvm, *pgd)) - unmap_stage2_puds(kvm, pgd, addr, next); - /* - * If the range is too large, release the kvm->mmu_lock - * to prevent starvation and lockup detector warnings. - */ - if (next != end) - cond_resched_lock(&kvm->mmu_lock); - } while (pgd++, addr = next, addr != end); -} - -static void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd, - phys_addr_t addr, phys_addr_t end) -{ - pte_t *pte; - - pte = pte_offset_kernel(pmd, addr); - do { - if (!pte_none(*pte) && !kvm_is_device_pfn(pte_pfn(*pte))) - kvm_flush_dcache_pte(*pte); - } while (pte++, addr += PAGE_SIZE, addr != end); -} - -static void stage2_flush_pmds(struct kvm *kvm, pud_t *pud, - phys_addr_t addr, phys_addr_t end) -{ - pmd_t *pmd; - phys_addr_t next; - - pmd = stage2_pmd_offset(kvm, pud, addr); - do { - next = stage2_pmd_addr_end(kvm, addr, end); - if (!pmd_none(*pmd)) { - if (pmd_thp_or_huge(*pmd)) - kvm_flush_dcache_pmd(*pmd); - else - stage2_flush_ptes(kvm, pmd, addr, next); - } - } while (pmd++, addr = next, addr != end); -} - -static void stage2_flush_puds(struct kvm *kvm, pgd_t *pgd, - phys_addr_t addr, phys_addr_t end) -{ - pud_t *pud; - phys_addr_t next; - - pud = stage2_pud_offset(kvm, pgd, addr); - do { - next = stage2_pud_addr_end(kvm, addr, end); - if (!stage2_pud_none(kvm, *pud)) { - if (stage2_pud_huge(kvm, *pud)) - kvm_flush_dcache_pud(*pud); - else - stage2_flush_pmds(kvm, pud, addr, next); - } - } while (pud++, addr = next, addr != end); -} - -static void stage2_flush_memslot(struct kvm *kvm, - struct kvm_memory_slot *memslot) -{ - phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT; - phys_addr_t end = addr + PAGE_SIZE * memslot->npages; - phys_addr_t next; - pgd_t *pgd; - - pgd = kvm->arch.pgd + stage2_pgd_index(kvm, addr); - do { - next = stage2_pgd_addr_end(kvm, addr, end); - if (!stage2_pgd_none(kvm, *pgd)) - stage2_flush_puds(kvm, pgd, addr, next); - } while (pgd++, addr = next, addr != end); -} - -/** - * stage2_flush_vm - Invalidate cache for pages mapped in stage 2 - * @kvm: The struct kvm pointer - * - * Go through the stage 2 page tables and invalidate any cache lines - * backing memory already mapped to the VM. - */ -static void stage2_flush_vm(struct kvm *kvm) -{ - struct kvm_memslots *slots; - struct kvm_memory_slot *memslot; - int idx; - - idx = srcu_read_lock(&kvm->srcu); - spin_lock(&kvm->mmu_lock); - - slots = kvm_memslots(kvm); - kvm_for_each_memslot(memslot, slots) - stage2_flush_memslot(kvm, memslot); - - spin_unlock(&kvm->mmu_lock); - srcu_read_unlock(&kvm->srcu, idx); -} - -static void clear_hyp_pgd_entry(pgd_t *pgd) -{ - pud_t *pud_table __maybe_unused = pud_offset(pgd, 0UL); - pgd_clear(pgd); - pud_free(NULL, pud_table); - put_page(virt_to_page(pgd)); -} - -static void clear_hyp_pud_entry(pud_t *pud) -{ - pmd_t *pmd_table __maybe_unused = pmd_offset(pud, 0); - VM_BUG_ON(pud_huge(*pud)); - pud_clear(pud); - pmd_free(NULL, pmd_table); - put_page(virt_to_page(pud)); -} - -static void clear_hyp_pmd_entry(pmd_t *pmd) -{ - pte_t *pte_table = pte_offset_kernel(pmd, 0); - VM_BUG_ON(pmd_thp_or_huge(*pmd)); - pmd_clear(pmd); - pte_free_kernel(NULL, pte_table); - put_page(virt_to_page(pmd)); -} - -static void unmap_hyp_ptes(pmd_t *pmd, phys_addr_t addr, phys_addr_t end) -{ - pte_t *pte, *start_pte; - - start_pte = pte = pte_offset_kernel(pmd, addr); - do { - if (!pte_none(*pte)) { - kvm_set_pte(pte, __pte(0)); - put_page(virt_to_page(pte)); - } - } while (pte++, addr += PAGE_SIZE, addr != end); - - if (hyp_pte_table_empty(start_pte)) - clear_hyp_pmd_entry(pmd); -} - -static void unmap_hyp_pmds(pud_t *pud, phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t next; - pmd_t *pmd, *start_pmd; - - start_pmd = pmd = pmd_offset(pud, addr); - do { - next = pmd_addr_end(addr, end); - /* Hyp doesn't use huge pmds */ - if (!pmd_none(*pmd)) - unmap_hyp_ptes(pmd, addr, next); - } while (pmd++, addr = next, addr != end); - - if (hyp_pmd_table_empty(start_pmd)) - clear_hyp_pud_entry(pud); -} - -static void unmap_hyp_puds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t next; - pud_t *pud, *start_pud; - - start_pud = pud = pud_offset(pgd, addr); - do { - next = pud_addr_end(addr, end); - /* Hyp doesn't use huge puds */ - if (!pud_none(*pud)) - unmap_hyp_pmds(pud, addr, next); - } while (pud++, addr = next, addr != end); - - if (hyp_pud_table_empty(start_pud)) - clear_hyp_pgd_entry(pgd); -} - -static unsigned int kvm_pgd_index(unsigned long addr, unsigned int ptrs_per_pgd) -{ - return (addr >> PGDIR_SHIFT) & (ptrs_per_pgd - 1); -} - -static void __unmap_hyp_range(pgd_t *pgdp, unsigned long ptrs_per_pgd, - phys_addr_t start, u64 size) -{ - pgd_t *pgd; - phys_addr_t addr = start, end = start + size; - phys_addr_t next; - - /* - * We don't unmap anything from HYP, except at the hyp tear down. - * Hence, we don't have to invalidate the TLBs here. - */ - pgd = pgdp + kvm_pgd_index(addr, ptrs_per_pgd); - do { - next = pgd_addr_end(addr, end); - if (!pgd_none(*pgd)) - unmap_hyp_puds(pgd, addr, next); - } while (pgd++, addr = next, addr != end); -} - -static void unmap_hyp_range(pgd_t *pgdp, phys_addr_t start, u64 size) -{ - __unmap_hyp_range(pgdp, PTRS_PER_PGD, start, size); -} - -static void unmap_hyp_idmap_range(pgd_t *pgdp, phys_addr_t start, u64 size) -{ - __unmap_hyp_range(pgdp, __kvm_idmap_ptrs_per_pgd(), start, size); -} - -/** - * free_hyp_pgds - free Hyp-mode page tables - * - * Assumes hyp_pgd is a page table used strictly in Hyp-mode and - * therefore contains either mappings in the kernel memory area (above - * PAGE_OFFSET), or device mappings in the idmap range. - * - * boot_hyp_pgd should only map the idmap range, and is only used in - * the extended idmap case. - */ -void free_hyp_pgds(void) -{ - pgd_t *id_pgd; - - mutex_lock(&kvm_hyp_pgd_mutex); - - id_pgd = boot_hyp_pgd ? boot_hyp_pgd : hyp_pgd; - - if (id_pgd) { - /* In case we never called hyp_mmu_init() */ - if (!io_map_base) - io_map_base = hyp_idmap_start; - unmap_hyp_idmap_range(id_pgd, io_map_base, - hyp_idmap_start + PAGE_SIZE - io_map_base); - } - - if (boot_hyp_pgd) { - free_pages((unsigned long)boot_hyp_pgd, hyp_pgd_order); - boot_hyp_pgd = NULL; - } - - if (hyp_pgd) { - unmap_hyp_range(hyp_pgd, kern_hyp_va(PAGE_OFFSET), - (uintptr_t)high_memory - PAGE_OFFSET); - - free_pages((unsigned long)hyp_pgd, hyp_pgd_order); - hyp_pgd = NULL; - } - if (merged_hyp_pgd) { - clear_page(merged_hyp_pgd); - free_page((unsigned long)merged_hyp_pgd); - merged_hyp_pgd = NULL; - } - - mutex_unlock(&kvm_hyp_pgd_mutex); -} - -static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start, - unsigned long end, unsigned long pfn, - pgprot_t prot) -{ - pte_t *pte; - unsigned long addr; - - addr = start; - do { - pte = pte_offset_kernel(pmd, addr); - kvm_set_pte(pte, kvm_pfn_pte(pfn, prot)); - get_page(virt_to_page(pte)); - pfn++; - } while (addr += PAGE_SIZE, addr != end); -} - -static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start, - unsigned long end, unsigned long pfn, - pgprot_t prot) -{ - pmd_t *pmd; - pte_t *pte; - unsigned long addr, next; - - addr = start; - do { - pmd = pmd_offset(pud, addr); - - BUG_ON(pmd_sect(*pmd)); - - if (pmd_none(*pmd)) { - pte = pte_alloc_one_kernel(NULL); - if (!pte) { - kvm_err("Cannot allocate Hyp pte\n"); - return -ENOMEM; - } - kvm_pmd_populate(pmd, pte); - get_page(virt_to_page(pmd)); - } - - next = pmd_addr_end(addr, end); - - create_hyp_pte_mappings(pmd, addr, next, pfn, prot); - pfn += (next - addr) >> PAGE_SHIFT; - } while (addr = next, addr != end); - - return 0; -} - -static int create_hyp_pud_mappings(pgd_t *pgd, unsigned long start, - unsigned long end, unsigned long pfn, - pgprot_t prot) -{ - pud_t *pud; - pmd_t *pmd; - unsigned long addr, next; - int ret; - - addr = start; - do { - pud = pud_offset(pgd, addr); - - if (pud_none_or_clear_bad(pud)) { - pmd = pmd_alloc_one(NULL, addr); - if (!pmd) { - kvm_err("Cannot allocate Hyp pmd\n"); - return -ENOMEM; - } - kvm_pud_populate(pud, pmd); - get_page(virt_to_page(pud)); - } - - next = pud_addr_end(addr, end); - ret = create_hyp_pmd_mappings(pud, addr, next, pfn, prot); - if (ret) - return ret; - pfn += (next - addr) >> PAGE_SHIFT; - } while (addr = next, addr != end); - - return 0; -} - -static int __create_hyp_mappings(pgd_t *pgdp, unsigned long ptrs_per_pgd, - unsigned long start, unsigned long end, - unsigned long pfn, pgprot_t prot) -{ - pgd_t *pgd; - pud_t *pud; - unsigned long addr, next; - int err = 0; - - mutex_lock(&kvm_hyp_pgd_mutex); - addr = start & PAGE_MASK; - end = PAGE_ALIGN(end); - do { - pgd = pgdp + kvm_pgd_index(addr, ptrs_per_pgd); - - if (pgd_none(*pgd)) { - pud = pud_alloc_one(NULL, addr); - if (!pud) { - kvm_err("Cannot allocate Hyp pud\n"); - err = -ENOMEM; - goto out; - } - kvm_pgd_populate(pgd, pud); - get_page(virt_to_page(pgd)); - } - - next = pgd_addr_end(addr, end); - err = create_hyp_pud_mappings(pgd, addr, next, pfn, prot); - if (err) - goto out; - pfn += (next - addr) >> PAGE_SHIFT; - } while (addr = next, addr != end); -out: - mutex_unlock(&kvm_hyp_pgd_mutex); - return err; -} - -static phys_addr_t kvm_kaddr_to_phys(void *kaddr) -{ - if (!is_vmalloc_addr(kaddr)) { - BUG_ON(!virt_addr_valid(kaddr)); - return __pa(kaddr); - } else { - return page_to_phys(vmalloc_to_page(kaddr)) + - offset_in_page(kaddr); - } -} - -/** - * create_hyp_mappings - duplicate a kernel virtual address range in Hyp mode - * @from: The virtual kernel start address of the range - * @to: The virtual kernel end address of the range (exclusive) - * @prot: The protection to be applied to this range - * - * The same virtual address as the kernel virtual address is also used - * in Hyp-mode mapping (modulo HYP_PAGE_OFFSET) to the same underlying - * physical pages. - */ -int create_hyp_mappings(void *from, void *to, pgprot_t prot) -{ - phys_addr_t phys_addr; - unsigned long virt_addr; - unsigned long start = kern_hyp_va((unsigned long)from); - unsigned long end = kern_hyp_va((unsigned long)to); - - if (is_kernel_in_hyp_mode()) - return 0; - - start = start & PAGE_MASK; - end = PAGE_ALIGN(end); - - for (virt_addr = start; virt_addr < end; virt_addr += PAGE_SIZE) { - int err; - - phys_addr = kvm_kaddr_to_phys(from + virt_addr - start); - err = __create_hyp_mappings(hyp_pgd, PTRS_PER_PGD, - virt_addr, virt_addr + PAGE_SIZE, - __phys_to_pfn(phys_addr), - prot); - if (err) - return err; - } - - return 0; -} - -static int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, - unsigned long *haddr, pgprot_t prot) -{ - pgd_t *pgd = hyp_pgd; - unsigned long base; - int ret = 0; - - mutex_lock(&kvm_hyp_pgd_mutex); - - /* - * This assumes that we we have enough space below the idmap - * page to allocate our VAs. If not, the check below will - * kick. A potential alternative would be to detect that - * overflow and switch to an allocation above the idmap. - * - * The allocated size is always a multiple of PAGE_SIZE. - */ - size = PAGE_ALIGN(size + offset_in_page(phys_addr)); - base = io_map_base - size; - - /* - * Verify that BIT(VA_BITS - 1) hasn't been flipped by - * allocating the new area, as it would indicate we've - * overflowed the idmap/IO address range. - */ - if ((base ^ io_map_base) & BIT(VA_BITS - 1)) - ret = -ENOMEM; - else - io_map_base = base; - - mutex_unlock(&kvm_hyp_pgd_mutex); - - if (ret) - goto out; - - if (__kvm_cpu_uses_extended_idmap()) - pgd = boot_hyp_pgd; - - ret = __create_hyp_mappings(pgd, __kvm_idmap_ptrs_per_pgd(), - base, base + size, - __phys_to_pfn(phys_addr), prot); - if (ret) - goto out; - - *haddr = base + offset_in_page(phys_addr); - -out: - return ret; -} - -/** - * create_hyp_io_mappings - Map IO into both kernel and HYP - * @phys_addr: The physical start address which gets mapped - * @size: Size of the region being mapped - * @kaddr: Kernel VA for this mapping - * @haddr: HYP VA for this mapping - */ -int create_hyp_io_mappings(phys_addr_t phys_addr, size_t size, - void __iomem **kaddr, - void __iomem **haddr) -{ - unsigned long addr; - int ret; - - *kaddr = ioremap(phys_addr, size); - if (!*kaddr) - return -ENOMEM; - - if (is_kernel_in_hyp_mode()) { - *haddr = *kaddr; - return 0; - } - - ret = __create_hyp_private_mapping(phys_addr, size, - &addr, PAGE_HYP_DEVICE); - if (ret) { - iounmap(*kaddr); - *kaddr = NULL; - *haddr = NULL; - return ret; - } - - *haddr = (void __iomem *)addr; - return 0; -} - -/** - * create_hyp_exec_mappings - Map an executable range into HYP - * @phys_addr: The physical start address which gets mapped - * @size: Size of the region being mapped - * @haddr: HYP VA for this mapping - */ -int create_hyp_exec_mappings(phys_addr_t phys_addr, size_t size, - void **haddr) -{ - unsigned long addr; - int ret; - - BUG_ON(is_kernel_in_hyp_mode()); - - ret = __create_hyp_private_mapping(phys_addr, size, - &addr, PAGE_HYP_EXEC); - if (ret) { - *haddr = NULL; - return ret; - } - - *haddr = (void *)addr; - return 0; -} - -/** - * kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation. - * @kvm: The KVM struct pointer for the VM. - * - * Allocates only the stage-2 HW PGD level table(s) of size defined by - * stage2_pgd_size(kvm). - * - * Note we don't need locking here as this is only called when the VM is - * created, which can only be done once. - */ -int kvm_alloc_stage2_pgd(struct kvm *kvm) -{ - phys_addr_t pgd_phys; - pgd_t *pgd; - - if (kvm->arch.pgd != NULL) { - kvm_err("kvm_arch already initialized?\n"); - return -EINVAL; - } - - /* Allocate the HW PGD, making sure that each page gets its own refcount */ - pgd = alloc_pages_exact(stage2_pgd_size(kvm), GFP_KERNEL | __GFP_ZERO); - if (!pgd) - return -ENOMEM; - - pgd_phys = virt_to_phys(pgd); - if (WARN_ON(pgd_phys & ~kvm_vttbr_baddr_mask(kvm))) - return -EINVAL; - - kvm->arch.pgd = pgd; - kvm->arch.pgd_phys = pgd_phys; - return 0; -} - -static void stage2_unmap_memslot(struct kvm *kvm, - struct kvm_memory_slot *memslot) -{ - hva_t hva = memslot->userspace_addr; - phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT; - phys_addr_t size = PAGE_SIZE * memslot->npages; - hva_t reg_end = hva + size; - - /* - * A memory region could potentially cover multiple VMAs, and any holes - * between them, so iterate over all of them to find out if we should - * unmap any of them. - * - * +--------------------------------------------+ - * +---------------+----------------+ +----------------+ - * | : VMA 1 | VMA 2 | | VMA 3 : | - * +---------------+----------------+ +----------------+ - * | memory region | - * +--------------------------------------------+ - */ - do { - struct vm_area_struct *vma = find_vma(current->mm, hva); - hva_t vm_start, vm_end; - - if (!vma || vma->vm_start >= reg_end) - break; - - /* - * Take the intersection of this VMA with the memory region - */ - vm_start = max(hva, vma->vm_start); - vm_end = min(reg_end, vma->vm_end); - - if (!(vma->vm_flags & VM_PFNMAP)) { - gpa_t gpa = addr + (vm_start - memslot->userspace_addr); - unmap_stage2_range(kvm, gpa, vm_end - vm_start); - } - hva = vm_end; - } while (hva < reg_end); -} - -/** - * stage2_unmap_vm - Unmap Stage-2 RAM mappings - * @kvm: The struct kvm pointer - * - * Go through the memregions and unmap any reguler RAM - * backing memory already mapped to the VM. - */ -void stage2_unmap_vm(struct kvm *kvm) -{ - struct kvm_memslots *slots; - struct kvm_memory_slot *memslot; - int idx; - - idx = srcu_read_lock(&kvm->srcu); - down_read(¤t->mm->mmap_sem); - spin_lock(&kvm->mmu_lock); - - slots = kvm_memslots(kvm); - kvm_for_each_memslot(memslot, slots) - stage2_unmap_memslot(kvm, memslot); - - spin_unlock(&kvm->mmu_lock); - up_read(¤t->mm->mmap_sem); - srcu_read_unlock(&kvm->srcu, idx); -} - -/** - * kvm_free_stage2_pgd - free all stage-2 tables - * @kvm: The KVM struct pointer for the VM. - * - * Walks the level-1 page table pointed to by kvm->arch.pgd and frees all - * underlying level-2 and level-3 tables before freeing the actual level-1 table - * and setting the struct pointer to NULL. - */ -void kvm_free_stage2_pgd(struct kvm *kvm) -{ - void *pgd = NULL; - - spin_lock(&kvm->mmu_lock); - if (kvm->arch.pgd) { - unmap_stage2_range(kvm, 0, kvm_phys_size(kvm)); - pgd = READ_ONCE(kvm->arch.pgd); - kvm->arch.pgd = NULL; - kvm->arch.pgd_phys = 0; - } - spin_unlock(&kvm->mmu_lock); - - /* Free the HW pgd, one page at a time */ - if (pgd) - free_pages_exact(pgd, stage2_pgd_size(kvm)); -} - -static pud_t *stage2_get_pud(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, - phys_addr_t addr) -{ - pgd_t *pgd; - pud_t *pud; - - pgd = kvm->arch.pgd + stage2_pgd_index(kvm, addr); - if (stage2_pgd_none(kvm, *pgd)) { - if (!cache) - return NULL; - pud = mmu_memory_cache_alloc(cache); - stage2_pgd_populate(kvm, pgd, pud); - get_page(virt_to_page(pgd)); - } - - return stage2_pud_offset(kvm, pgd, addr); -} - -static pmd_t *stage2_get_pmd(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, - phys_addr_t addr) -{ - pud_t *pud; - pmd_t *pmd; - - pud = stage2_get_pud(kvm, cache, addr); - if (!pud || stage2_pud_huge(kvm, *pud)) - return NULL; - - if (stage2_pud_none(kvm, *pud)) { - if (!cache) - return NULL; - pmd = mmu_memory_cache_alloc(cache); - stage2_pud_populate(kvm, pud, pmd); - get_page(virt_to_page(pud)); - } - - return stage2_pmd_offset(kvm, pud, addr); -} - -static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache - *cache, phys_addr_t addr, const pmd_t *new_pmd) -{ - pmd_t *pmd, old_pmd; - -retry: - pmd = stage2_get_pmd(kvm, cache, addr); - VM_BUG_ON(!pmd); - - old_pmd = *pmd; - /* - * Multiple vcpus faulting on the same PMD entry, can - * lead to them sequentially updating the PMD with the - * same value. Following the break-before-make - * (pmd_clear() followed by tlb_flush()) process can - * hinder forward progress due to refaults generated - * on missing translations. - * - * Skip updating the page table if the entry is - * unchanged. - */ - if (pmd_val(old_pmd) == pmd_val(*new_pmd)) - return 0; - - if (pmd_present(old_pmd)) { - /* - * If we already have PTE level mapping for this block, - * we must unmap it to avoid inconsistent TLB state and - * leaking the table page. We could end up in this situation - * if the memory slot was marked for dirty logging and was - * reverted, leaving PTE level mappings for the pages accessed - * during the period. So, unmap the PTE level mapping for this - * block and retry, as we could have released the upper level - * table in the process. - * - * Normal THP split/merge follows mmu_notifier callbacks and do - * get handled accordingly. - */ - if (!pmd_thp_or_huge(old_pmd)) { - unmap_stage2_range(kvm, addr & S2_PMD_MASK, S2_PMD_SIZE); - goto retry; - } - /* - * Mapping in huge pages should only happen through a - * fault. If a page is merged into a transparent huge - * page, the individual subpages of that huge page - * should be unmapped through MMU notifiers before we - * get here. - * - * Merging of CompoundPages is not supported; they - * should become splitting first, unmapped, merged, - * and mapped back in on-demand. - */ - WARN_ON_ONCE(pmd_pfn(old_pmd) != pmd_pfn(*new_pmd)); - pmd_clear(pmd); - kvm_tlb_flush_vmid_ipa(kvm, addr); - } else { - get_page(virt_to_page(pmd)); - } - - kvm_set_pmd(pmd, *new_pmd); - return 0; -} - -static int stage2_set_pud_huge(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, - phys_addr_t addr, const pud_t *new_pudp) -{ - pud_t *pudp, old_pud; - -retry: - pudp = stage2_get_pud(kvm, cache, addr); - VM_BUG_ON(!pudp); - - old_pud = *pudp; - - /* - * A large number of vcpus faulting on the same stage 2 entry, - * can lead to a refault due to the stage2_pud_clear()/tlb_flush(). - * Skip updating the page tables if there is no change. - */ - if (pud_val(old_pud) == pud_val(*new_pudp)) - return 0; - - if (stage2_pud_present(kvm, old_pud)) { - /* - * If we already have table level mapping for this block, unmap - * the range for this block and retry. - */ - if (!stage2_pud_huge(kvm, old_pud)) { - unmap_stage2_range(kvm, addr & S2_PUD_MASK, S2_PUD_SIZE); - goto retry; - } - - WARN_ON_ONCE(kvm_pud_pfn(old_pud) != kvm_pud_pfn(*new_pudp)); - stage2_pud_clear(kvm, pudp); - kvm_tlb_flush_vmid_ipa(kvm, addr); - } else { - get_page(virt_to_page(pudp)); - } - - kvm_set_pud(pudp, *new_pudp); - return 0; -} - -/* - * stage2_get_leaf_entry - walk the stage2 VM page tables and return - * true if a valid and present leaf-entry is found. A pointer to the - * leaf-entry is returned in the appropriate level variable - pudpp, - * pmdpp, ptepp. - */ -static bool stage2_get_leaf_entry(struct kvm *kvm, phys_addr_t addr, - pud_t **pudpp, pmd_t **pmdpp, pte_t **ptepp) -{ - pud_t *pudp; - pmd_t *pmdp; - pte_t *ptep; - - *pudpp = NULL; - *pmdpp = NULL; - *ptepp = NULL; - - pudp = stage2_get_pud(kvm, NULL, addr); - if (!pudp || stage2_pud_none(kvm, *pudp) || !stage2_pud_present(kvm, *pudp)) - return false; - - if (stage2_pud_huge(kvm, *pudp)) { - *pudpp = pudp; - return true; - } - - pmdp = stage2_pmd_offset(kvm, pudp, addr); - if (!pmdp || pmd_none(*pmdp) || !pmd_present(*pmdp)) - return false; - - if (pmd_thp_or_huge(*pmdp)) { - *pmdpp = pmdp; - return true; - } - - ptep = pte_offset_kernel(pmdp, addr); - if (!ptep || pte_none(*ptep) || !pte_present(*ptep)) - return false; - - *ptepp = ptep; - return true; -} - -static bool stage2_is_exec(struct kvm *kvm, phys_addr_t addr) -{ - pud_t *pudp; - pmd_t *pmdp; - pte_t *ptep; - bool found; - - found = stage2_get_leaf_entry(kvm, addr, &pudp, &pmdp, &ptep); - if (!found) - return false; - - if (pudp) - return kvm_s2pud_exec(pudp); - else if (pmdp) - return kvm_s2pmd_exec(pmdp); - else - return kvm_s2pte_exec(ptep); -} - -static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, - phys_addr_t addr, const pte_t *new_pte, - unsigned long flags) -{ - pud_t *pud; - pmd_t *pmd; - pte_t *pte, old_pte; - bool iomap = flags & KVM_S2PTE_FLAG_IS_IOMAP; - bool logging_active = flags & KVM_S2_FLAG_LOGGING_ACTIVE; - - VM_BUG_ON(logging_active && !cache); - - /* Create stage-2 page table mapping - Levels 0 and 1 */ - pud = stage2_get_pud(kvm, cache, addr); - if (!pud) { - /* - * Ignore calls from kvm_set_spte_hva for unallocated - * address ranges. - */ - return 0; - } - - /* - * While dirty page logging - dissolve huge PUD, then continue - * on to allocate page. - */ - if (logging_active) - stage2_dissolve_pud(kvm, addr, pud); - - if (stage2_pud_none(kvm, *pud)) { - if (!cache) - return 0; /* ignore calls from kvm_set_spte_hva */ - pmd = mmu_memory_cache_alloc(cache); - stage2_pud_populate(kvm, pud, pmd); - get_page(virt_to_page(pud)); - } - - pmd = stage2_pmd_offset(kvm, pud, addr); - if (!pmd) { - /* - * Ignore calls from kvm_set_spte_hva for unallocated - * address ranges. - */ - return 0; - } - - /* - * While dirty page logging - dissolve huge PMD, then continue on to - * allocate page. - */ - if (logging_active) - stage2_dissolve_pmd(kvm, addr, pmd); - - /* Create stage-2 page mappings - Level 2 */ - if (pmd_none(*pmd)) { - if (!cache) - return 0; /* ignore calls from kvm_set_spte_hva */ - pte = mmu_memory_cache_alloc(cache); - kvm_pmd_populate(pmd, pte); - get_page(virt_to_page(pmd)); - } - - pte = pte_offset_kernel(pmd, addr); - - if (iomap && pte_present(*pte)) - return -EFAULT; - - /* Create 2nd stage page table mapping - Level 3 */ - old_pte = *pte; - if (pte_present(old_pte)) { - /* Skip page table update if there is no change */ - if (pte_val(old_pte) == pte_val(*new_pte)) - return 0; - - kvm_set_pte(pte, __pte(0)); - kvm_tlb_flush_vmid_ipa(kvm, addr); - } else { - get_page(virt_to_page(pte)); - } - - kvm_set_pte(pte, *new_pte); - return 0; -} - -#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG -static int stage2_ptep_test_and_clear_young(pte_t *pte) -{ - if (pte_young(*pte)) { - *pte = pte_mkold(*pte); - return 1; - } - return 0; -} -#else -static int stage2_ptep_test_and_clear_young(pte_t *pte) -{ - return __ptep_test_and_clear_young(pte); -} -#endif - -static int stage2_pmdp_test_and_clear_young(pmd_t *pmd) -{ - return stage2_ptep_test_and_clear_young((pte_t *)pmd); -} - -static int stage2_pudp_test_and_clear_young(pud_t *pud) -{ - return stage2_ptep_test_and_clear_young((pte_t *)pud); -} - -/** - * kvm_phys_addr_ioremap - map a device range to guest IPA - * - * @kvm: The KVM pointer - * @guest_ipa: The IPA at which to insert the mapping - * @pa: The physical address of the device - * @size: The size of the mapping - */ -int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, - phys_addr_t pa, unsigned long size, bool writable) -{ - phys_addr_t addr, end; - int ret = 0; - unsigned long pfn; - struct kvm_mmu_memory_cache cache = { 0, }; - - end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK; - pfn = __phys_to_pfn(pa); - - for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) { - pte_t pte = kvm_pfn_pte(pfn, PAGE_S2_DEVICE); - - if (writable) - pte = kvm_s2pte_mkwrite(pte); - - ret = mmu_topup_memory_cache(&cache, - kvm_mmu_cache_min_pages(kvm), - KVM_NR_MEM_OBJS); - if (ret) - goto out; - spin_lock(&kvm->mmu_lock); - ret = stage2_set_pte(kvm, &cache, addr, &pte, - KVM_S2PTE_FLAG_IS_IOMAP); - spin_unlock(&kvm->mmu_lock); - if (ret) - goto out; - - pfn++; - } - -out: - mmu_free_memory_cache(&cache); - return ret; -} - -static bool transparent_hugepage_adjust(kvm_pfn_t *pfnp, phys_addr_t *ipap) -{ - kvm_pfn_t pfn = *pfnp; - gfn_t gfn = *ipap >> PAGE_SHIFT; - - if (kvm_is_transparent_hugepage(pfn)) { - unsigned long mask; - /* - * The address we faulted on is backed by a transparent huge - * page. However, because we map the compound huge page and - * not the individual tail page, we need to transfer the - * refcount to the head page. We have to be careful that the - * THP doesn't start to split while we are adjusting the - * refcounts. - * - * We are sure this doesn't happen, because mmu_notifier_retry - * was successful and we are holding the mmu_lock, so if this - * THP is trying to split, it will be blocked in the mmu - * notifier before touching any of the pages, specifically - * before being able to call __split_huge_page_refcount(). - * - * We can therefore safely transfer the refcount from PG_tail - * to PG_head and switch the pfn from a tail page to the head - * page accordingly. - */ - mask = PTRS_PER_PMD - 1; - VM_BUG_ON((gfn & mask) != (pfn & mask)); - if (pfn & mask) { - *ipap &= PMD_MASK; - kvm_release_pfn_clean(pfn); - pfn &= ~mask; - kvm_get_pfn(pfn); - *pfnp = pfn; - } - - return true; - } - - return false; -} - -/** - * stage2_wp_ptes - write protect PMD range - * @pmd: pointer to pmd entry - * @addr: range start address - * @end: range end address - */ -static void stage2_wp_ptes(pmd_t *pmd, phys_addr_t addr, phys_addr_t end) -{ - pte_t *pte; - - pte = pte_offset_kernel(pmd, addr); - do { - if (!pte_none(*pte)) { - if (!kvm_s2pte_readonly(pte)) - kvm_set_s2pte_readonly(pte); - } - } while (pte++, addr += PAGE_SIZE, addr != end); -} - -/** - * stage2_wp_pmds - write protect PUD range - * kvm: kvm instance for the VM - * @pud: pointer to pud entry - * @addr: range start address - * @end: range end address - */ -static void stage2_wp_pmds(struct kvm *kvm, pud_t *pud, - phys_addr_t addr, phys_addr_t end) -{ - pmd_t *pmd; - phys_addr_t next; - - pmd = stage2_pmd_offset(kvm, pud, addr); - - do { - next = stage2_pmd_addr_end(kvm, addr, end); - if (!pmd_none(*pmd)) { - if (pmd_thp_or_huge(*pmd)) { - if (!kvm_s2pmd_readonly(pmd)) - kvm_set_s2pmd_readonly(pmd); - } else { - stage2_wp_ptes(pmd, addr, next); - } - } - } while (pmd++, addr = next, addr != end); -} - -/** - * stage2_wp_puds - write protect PGD range - * @pgd: pointer to pgd entry - * @addr: range start address - * @end: range end address - */ -static void stage2_wp_puds(struct kvm *kvm, pgd_t *pgd, - phys_addr_t addr, phys_addr_t end) -{ - pud_t *pud; - phys_addr_t next; - - pud = stage2_pud_offset(kvm, pgd, addr); - do { - next = stage2_pud_addr_end(kvm, addr, end); - if (!stage2_pud_none(kvm, *pud)) { - if (stage2_pud_huge(kvm, *pud)) { - if (!kvm_s2pud_readonly(pud)) - kvm_set_s2pud_readonly(pud); - } else { - stage2_wp_pmds(kvm, pud, addr, next); - } - } - } while (pud++, addr = next, addr != end); -} - -/** - * stage2_wp_range() - write protect stage2 memory region range - * @kvm: The KVM pointer - * @addr: Start address of range - * @end: End address of range - */ -static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) -{ - pgd_t *pgd; - phys_addr_t next; - - pgd = kvm->arch.pgd + stage2_pgd_index(kvm, addr); - do { - /* - * Release kvm_mmu_lock periodically if the memory region is - * large. Otherwise, we may see kernel panics with - * CONFIG_DETECT_HUNG_TASK, CONFIG_LOCKUP_DETECTOR, - * CONFIG_LOCKDEP. Additionally, holding the lock too long - * will also starve other vCPUs. We have to also make sure - * that the page tables are not freed while we released - * the lock. - */ - cond_resched_lock(&kvm->mmu_lock); - if (!READ_ONCE(kvm->arch.pgd)) - break; - next = stage2_pgd_addr_end(kvm, addr, end); - if (stage2_pgd_present(kvm, *pgd)) - stage2_wp_puds(kvm, pgd, addr, next); - } while (pgd++, addr = next, addr != end); -} - -/** - * kvm_mmu_wp_memory_region() - write protect stage 2 entries for memory slot - * @kvm: The KVM pointer - * @slot: The memory slot to write protect - * - * Called to start logging dirty pages after memory region - * KVM_MEM_LOG_DIRTY_PAGES operation is called. After this function returns - * all present PUD, PMD and PTEs are write protected in the memory region. - * Afterwards read of dirty page log can be called. - * - * Acquires kvm_mmu_lock. Called with kvm->slots_lock mutex acquired, - * serializing operations for VM memory regions. - */ -void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot) -{ - struct kvm_memslots *slots = kvm_memslots(kvm); - struct kvm_memory_slot *memslot = id_to_memslot(slots, slot); - phys_addr_t start, end; - - if (WARN_ON_ONCE(!memslot)) - return; - - start = memslot->base_gfn << PAGE_SHIFT; - end = (memslot->base_gfn + memslot->npages) << PAGE_SHIFT; - - spin_lock(&kvm->mmu_lock); - stage2_wp_range(kvm, start, end); - spin_unlock(&kvm->mmu_lock); - kvm_flush_remote_tlbs(kvm); -} - -/** - * kvm_mmu_write_protect_pt_masked() - write protect dirty pages - * @kvm: The KVM pointer - * @slot: The memory slot associated with mask - * @gfn_offset: The gfn offset in memory slot - * @mask: The mask of dirty pages at offset 'gfn_offset' in this memory - * slot to be write protected - * - * Walks bits set in mask write protects the associated pte's. Caller must - * acquire kvm_mmu_lock. - */ -static void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, - struct kvm_memory_slot *slot, - gfn_t gfn_offset, unsigned long mask) -{ - phys_addr_t base_gfn = slot->base_gfn + gfn_offset; - phys_addr_t start = (base_gfn + __ffs(mask)) << PAGE_SHIFT; - phys_addr_t end = (base_gfn + __fls(mask) + 1) << PAGE_SHIFT; - - stage2_wp_range(kvm, start, end); -} - -/* - * kvm_arch_mmu_enable_log_dirty_pt_masked - enable dirty logging for selected - * dirty pages. - * - * It calls kvm_mmu_write_protect_pt_masked to write protect selected pages to - * enable dirty logging for them. - */ -void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, - struct kvm_memory_slot *slot, - gfn_t gfn_offset, unsigned long mask) -{ - kvm_mmu_write_protect_pt_masked(kvm, slot, gfn_offset, mask); -} - -static void clean_dcache_guest_page(kvm_pfn_t pfn, unsigned long size) -{ - __clean_dcache_guest_page(pfn, size); -} - -static void invalidate_icache_guest_page(kvm_pfn_t pfn, unsigned long size) -{ - __invalidate_icache_guest_page(pfn, size); -} - -static void kvm_send_hwpoison_signal(unsigned long address, short lsb) -{ - send_sig_mceerr(BUS_MCEERR_AR, (void __user *)address, lsb, current); -} - -static bool fault_supports_stage2_huge_mapping(struct kvm_memory_slot *memslot, - unsigned long hva, - unsigned long map_size) -{ - gpa_t gpa_start; - hva_t uaddr_start, uaddr_end; - size_t size; - - size = memslot->npages * PAGE_SIZE; - - gpa_start = memslot->base_gfn << PAGE_SHIFT; - - uaddr_start = memslot->userspace_addr; - uaddr_end = uaddr_start + size; - - /* - * Pages belonging to memslots that don't have the same alignment - * within a PMD/PUD for userspace and IPA cannot be mapped with stage-2 - * PMD/PUD entries, because we'll end up mapping the wrong pages. - * - * Consider a layout like the following: - * - * memslot->userspace_addr: - * +-----+--------------------+--------------------+---+ - * |abcde|fgh Stage-1 block | Stage-1 block tv|xyz| - * +-----+--------------------+--------------------+---+ - * - * memslot->base_gfn << PAGE_SIZE: - * +---+--------------------+--------------------+-----+ - * |abc|def Stage-2 block | Stage-2 block |tvxyz| - * +---+--------------------+--------------------+-----+ - * - * If we create those stage-2 blocks, we'll end up with this incorrect - * mapping: - * d -> f - * e -> g - * f -> h - */ - if ((gpa_start & (map_size - 1)) != (uaddr_start & (map_size - 1))) - return false; - - /* - * Next, let's make sure we're not trying to map anything not covered - * by the memslot. This means we have to prohibit block size mappings - * for the beginning and end of a non-block aligned and non-block sized - * memory slot (illustrated by the head and tail parts of the - * userspace view above containing pages 'abcde' and 'xyz', - * respectively). - * - * Note that it doesn't matter if we do the check using the - * userspace_addr or the base_gfn, as both are equally aligned (per - * the check above) and equally sized. - */ - return (hva & ~(map_size - 1)) >= uaddr_start && - (hva & ~(map_size - 1)) + map_size <= uaddr_end; -} - -static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, - struct kvm_memory_slot *memslot, unsigned long hva, - unsigned long fault_status) -{ - int ret; - bool write_fault, writable, force_pte = false; - bool exec_fault, needs_exec; - unsigned long mmu_seq; - gfn_t gfn = fault_ipa >> PAGE_SHIFT; - struct kvm *kvm = vcpu->kvm; - struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache; - struct vm_area_struct *vma; - short vma_shift; - kvm_pfn_t pfn; - pgprot_t mem_type = PAGE_S2; - bool logging_active = memslot_is_logging(memslot); - unsigned long vma_pagesize, flags = 0; - - write_fault = kvm_is_write_fault(vcpu); - exec_fault = kvm_vcpu_trap_is_iabt(vcpu); - VM_BUG_ON(write_fault && exec_fault); - - if (fault_status == FSC_PERM && !write_fault && !exec_fault) { - kvm_err("Unexpected L2 read permission error\n"); - return -EFAULT; - } - - /* Let's check if we will get back a huge page backed by hugetlbfs */ - down_read(¤t->mm->mmap_sem); - vma = find_vma_intersection(current->mm, hva, hva + 1); - if (unlikely(!vma)) { - kvm_err("Failed to find VMA for hva 0x%lx\n", hva); - up_read(¤t->mm->mmap_sem); - return -EFAULT; - } - - if (is_vm_hugetlb_page(vma)) - vma_shift = huge_page_shift(hstate_vma(vma)); - else - vma_shift = PAGE_SHIFT; - - vma_pagesize = 1ULL << vma_shift; - if (logging_active || - (vma->vm_flags & VM_PFNMAP) || - !fault_supports_stage2_huge_mapping(memslot, hva, vma_pagesize)) { - force_pte = true; - vma_pagesize = PAGE_SIZE; - } - - /* - * The stage2 has a minimum of 2 level table (For arm64 see - * kvm_arm_setup_stage2()). Hence, we are guaranteed that we can - * use PMD_SIZE huge mappings (even when the PMD is folded into PGD). - * As for PUD huge maps, we must make sure that we have at least - * 3 levels, i.e, PMD is not folded. - */ - if (vma_pagesize == PMD_SIZE || - (vma_pagesize == PUD_SIZE && kvm_stage2_has_pmd(kvm))) - gfn = (fault_ipa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT; - up_read(¤t->mm->mmap_sem); - - /* We need minimum second+third level pages */ - ret = mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm), - KVM_NR_MEM_OBJS); - if (ret) - return ret; - - mmu_seq = vcpu->kvm->mmu_notifier_seq; - /* - * Ensure the read of mmu_notifier_seq happens before we call - * gfn_to_pfn_prot (which calls get_user_pages), so that we don't risk - * the page we just got a reference to gets unmapped before we have a - * chance to grab the mmu_lock, which ensure that if the page gets - * unmapped afterwards, the call to kvm_unmap_hva will take it away - * from us again properly. This smp_rmb() interacts with the smp_wmb() - * in kvm_mmu_notifier_invalidate_<page|range_end>. - */ - smp_rmb(); - - pfn = gfn_to_pfn_prot(kvm, gfn, write_fault, &writable); - if (pfn == KVM_PFN_ERR_HWPOISON) { - kvm_send_hwpoison_signal(hva, vma_shift); - return 0; - } - if (is_error_noslot_pfn(pfn)) - return -EFAULT; - - if (kvm_is_device_pfn(pfn)) { - mem_type = PAGE_S2_DEVICE; - flags |= KVM_S2PTE_FLAG_IS_IOMAP; - } else if (logging_active) { - /* - * Faults on pages in a memslot with logging enabled - * should not be mapped with huge pages (it introduces churn - * and performance degradation), so force a pte mapping. - */ - flags |= KVM_S2_FLAG_LOGGING_ACTIVE; - - /* - * Only actually map the page as writable if this was a write - * fault. - */ - if (!write_fault) - writable = false; - } - - if (exec_fault && is_iomap(flags)) - return -ENOEXEC; - - spin_lock(&kvm->mmu_lock); - if (mmu_notifier_retry(kvm, mmu_seq)) - goto out_unlock; - - if (vma_pagesize == PAGE_SIZE && !force_pte) { - /* - * Only PMD_SIZE transparent hugepages(THP) are - * currently supported. This code will need to be - * updated to support other THP sizes. - * - * Make sure the host VA and the guest IPA are sufficiently - * aligned and that the block is contained within the memslot. - */ - if (fault_supports_stage2_huge_mapping(memslot, hva, PMD_SIZE) && - transparent_hugepage_adjust(&pfn, &fault_ipa)) - vma_pagesize = PMD_SIZE; - } - - if (writable) - kvm_set_pfn_dirty(pfn); - - if (fault_status != FSC_PERM && !is_iomap(flags)) - clean_dcache_guest_page(pfn, vma_pagesize); - - if (exec_fault) - invalidate_icache_guest_page(pfn, vma_pagesize); - - /* - * If we took an execution fault we have made the - * icache/dcache coherent above and should now let the s2 - * mapping be executable. - * - * Write faults (!exec_fault && FSC_PERM) are orthogonal to - * execute permissions, and we preserve whatever we have. - */ - needs_exec = exec_fault || - (fault_status == FSC_PERM && stage2_is_exec(kvm, fault_ipa)); - - if (vma_pagesize == PUD_SIZE) { - pud_t new_pud = kvm_pfn_pud(pfn, mem_type); - - new_pud = kvm_pud_mkhuge(new_pud); - if (writable) - new_pud = kvm_s2pud_mkwrite(new_pud); - - if (needs_exec) - new_pud = kvm_s2pud_mkexec(new_pud); - - ret = stage2_set_pud_huge(kvm, memcache, fault_ipa, &new_pud); - } else if (vma_pagesize == PMD_SIZE) { - pmd_t new_pmd = kvm_pfn_pmd(pfn, mem_type); - - new_pmd = kvm_pmd_mkhuge(new_pmd); - - if (writable) - new_pmd = kvm_s2pmd_mkwrite(new_pmd); - - if (needs_exec) - new_pmd = kvm_s2pmd_mkexec(new_pmd); - - ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd); - } else { - pte_t new_pte = kvm_pfn_pte(pfn, mem_type); - - if (writable) { - new_pte = kvm_s2pte_mkwrite(new_pte); - mark_page_dirty(kvm, gfn); - } - - if (needs_exec) - new_pte = kvm_s2pte_mkexec(new_pte); - - ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, flags); - } - -out_unlock: - spin_unlock(&kvm->mmu_lock); - kvm_set_pfn_accessed(pfn); - kvm_release_pfn_clean(pfn); - return ret; -} - -/* - * Resolve the access fault by making the page young again. - * Note that because the faulting entry is guaranteed not to be - * cached in the TLB, we don't need to invalidate anything. - * Only the HW Access Flag updates are supported for Stage 2 (no DBM), - * so there is no need for atomic (pte|pmd)_mkyoung operations. - */ -static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa) -{ - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - kvm_pfn_t pfn; - bool pfn_valid = false; - - trace_kvm_access_fault(fault_ipa); - - spin_lock(&vcpu->kvm->mmu_lock); - - if (!stage2_get_leaf_entry(vcpu->kvm, fault_ipa, &pud, &pmd, &pte)) - goto out; - - if (pud) { /* HugeTLB */ - *pud = kvm_s2pud_mkyoung(*pud); - pfn = kvm_pud_pfn(*pud); - pfn_valid = true; - } else if (pmd) { /* THP, HugeTLB */ - *pmd = pmd_mkyoung(*pmd); - pfn = pmd_pfn(*pmd); - pfn_valid = true; - } else { - *pte = pte_mkyoung(*pte); /* Just a page... */ - pfn = pte_pfn(*pte); - pfn_valid = true; - } - -out: - spin_unlock(&vcpu->kvm->mmu_lock); - if (pfn_valid) - kvm_set_pfn_accessed(pfn); -} - -/** - * kvm_handle_guest_abort - handles all 2nd stage aborts - * @vcpu: the VCPU pointer - * @run: the kvm_run structure - * - * Any abort that gets to the host is almost guaranteed to be caused by a - * missing second stage translation table entry, which can mean that either the - * guest simply needs more memory and we must allocate an appropriate page or it - * can mean that the guest tried to access I/O memory, which is emulated by user - * space. The distinction is based on the IPA causing the fault and whether this - * memory region has been registered as standard RAM by user space. - */ -int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run) -{ - unsigned long fault_status; - phys_addr_t fault_ipa; - struct kvm_memory_slot *memslot; - unsigned long hva; - bool is_iabt, write_fault, writable; - gfn_t gfn; - int ret, idx; - - fault_status = kvm_vcpu_trap_get_fault_type(vcpu); - - fault_ipa = kvm_vcpu_get_fault_ipa(vcpu); - is_iabt = kvm_vcpu_trap_is_iabt(vcpu); - - /* Synchronous External Abort? */ - if (kvm_vcpu_dabt_isextabt(vcpu)) { - /* - * For RAS the host kernel may handle this abort. - * There is no need to pass the error into the guest. - */ - if (!kvm_handle_guest_sea(fault_ipa, kvm_vcpu_get_hsr(vcpu))) - return 1; - - if (unlikely(!is_iabt)) { - kvm_inject_vabt(vcpu); - return 1; - } - } - - trace_kvm_guest_fault(*vcpu_pc(vcpu), kvm_vcpu_get_hsr(vcpu), - kvm_vcpu_get_hfar(vcpu), fault_ipa); - - /* Check the stage-2 fault is trans. fault or write fault */ - if (fault_status != FSC_FAULT && fault_status != FSC_PERM && - fault_status != FSC_ACCESS) { - kvm_err("Unsupported FSC: EC=%#x xFSC=%#lx ESR_EL2=%#lx\n", - kvm_vcpu_trap_get_class(vcpu), - (unsigned long)kvm_vcpu_trap_get_fault(vcpu), - (unsigned long)kvm_vcpu_get_hsr(vcpu)); - return -EFAULT; - } - - idx = srcu_read_lock(&vcpu->kvm->srcu); - - gfn = fault_ipa >> PAGE_SHIFT; - memslot = gfn_to_memslot(vcpu->kvm, gfn); - hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable); - write_fault = kvm_is_write_fault(vcpu); - if (kvm_is_error_hva(hva) || (write_fault && !writable)) { - if (is_iabt) { - /* Prefetch Abort on I/O address */ - ret = -ENOEXEC; - goto out; - } - - /* - * Check for a cache maintenance operation. Since we - * ended-up here, we know it is outside of any memory - * slot. But we can't find out if that is for a device, - * or if the guest is just being stupid. The only thing - * we know for sure is that this range cannot be cached. - * - * So let's assume that the guest is just being - * cautious, and skip the instruction. - */ - if (kvm_vcpu_dabt_is_cm(vcpu)) { - kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); - ret = 1; - goto out_unlock; - } - - /* - * The IPA is reported as [MAX:12], so we need to - * complement it with the bottom 12 bits from the - * faulting VA. This is always 12 bits, irrespective - * of the page size. - */ - fault_ipa |= kvm_vcpu_get_hfar(vcpu) & ((1 << 12) - 1); - ret = io_mem_abort(vcpu, run, fault_ipa); - goto out_unlock; - } - - /* Userspace should not be able to register out-of-bounds IPAs */ - VM_BUG_ON(fault_ipa >= kvm_phys_size(vcpu->kvm)); - - if (fault_status == FSC_ACCESS) { - handle_access_fault(vcpu, fault_ipa); - ret = 1; - goto out_unlock; - } - - ret = user_mem_abort(vcpu, fault_ipa, memslot, hva, fault_status); - if (ret == 0) - ret = 1; -out: - if (ret == -ENOEXEC) { - kvm_inject_pabt(vcpu, kvm_vcpu_get_hfar(vcpu)); - ret = 1; - } -out_unlock: - srcu_read_unlock(&vcpu->kvm->srcu, idx); - return ret; -} - -static int handle_hva_to_gpa(struct kvm *kvm, - unsigned long start, - unsigned long end, - int (*handler)(struct kvm *kvm, - gpa_t gpa, u64 size, - void *data), - void *data) -{ - struct kvm_memslots *slots; - struct kvm_memory_slot *memslot; - int ret = 0; - - slots = kvm_memslots(kvm); - - /* we only care about the pages that the guest sees */ - kvm_for_each_memslot(memslot, slots) { - unsigned long hva_start, hva_end; - gfn_t gpa; - - hva_start = max(start, memslot->userspace_addr); - hva_end = min(end, memslot->userspace_addr + - (memslot->npages << PAGE_SHIFT)); - if (hva_start >= hva_end) - continue; - - gpa = hva_to_gfn_memslot(hva_start, memslot) << PAGE_SHIFT; - ret |= handler(kvm, gpa, (u64)(hva_end - hva_start), data); - } - - return ret; -} - -static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data) -{ - unmap_stage2_range(kvm, gpa, size); - return 0; -} - -int kvm_unmap_hva_range(struct kvm *kvm, - unsigned long start, unsigned long end) -{ - if (!kvm->arch.pgd) - return 0; - - trace_kvm_unmap_hva_range(start, end); - handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL); - return 0; -} - -static int kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data) -{ - pte_t *pte = (pte_t *)data; - - WARN_ON(size != PAGE_SIZE); - /* - * We can always call stage2_set_pte with KVM_S2PTE_FLAG_LOGGING_ACTIVE - * flag clear because MMU notifiers will have unmapped a huge PMD before - * calling ->change_pte() (which in turn calls kvm_set_spte_hva()) and - * therefore stage2_set_pte() never needs to clear out a huge PMD - * through this calling path. - */ - stage2_set_pte(kvm, NULL, gpa, pte, 0); - return 0; -} - - -int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) -{ - unsigned long end = hva + PAGE_SIZE; - kvm_pfn_t pfn = pte_pfn(pte); - pte_t stage2_pte; - - if (!kvm->arch.pgd) - return 0; - - trace_kvm_set_spte_hva(hva); - - /* - * We've moved a page around, probably through CoW, so let's treat it - * just like a translation fault and clean the cache to the PoC. - */ - clean_dcache_guest_page(pfn, PAGE_SIZE); - stage2_pte = kvm_pfn_pte(pfn, PAGE_S2); - handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte); - - return 0; -} - -static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data) -{ - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - if (!stage2_get_leaf_entry(kvm, gpa, &pud, &pmd, &pte)) - return 0; - - if (pud) - return stage2_pudp_test_and_clear_young(pud); - else if (pmd) - return stage2_pmdp_test_and_clear_young(pmd); - else - return stage2_ptep_test_and_clear_young(pte); -} - -static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data) -{ - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - if (!stage2_get_leaf_entry(kvm, gpa, &pud, &pmd, &pte)) - return 0; - - if (pud) - return kvm_s2pud_young(*pud); - else if (pmd) - return pmd_young(*pmd); - else - return pte_young(*pte); -} - -int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end) -{ - if (!kvm->arch.pgd) - return 0; - trace_kvm_age_hva(start, end); - return handle_hva_to_gpa(kvm, start, end, kvm_age_hva_handler, NULL); -} - -int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) -{ - if (!kvm->arch.pgd) - return 0; - trace_kvm_test_age_hva(hva); - return handle_hva_to_gpa(kvm, hva, hva + PAGE_SIZE, - kvm_test_age_hva_handler, NULL); -} - -void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu) -{ - mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); -} - -phys_addr_t kvm_mmu_get_httbr(void) -{ - if (__kvm_cpu_uses_extended_idmap()) - return virt_to_phys(merged_hyp_pgd); - else - return virt_to_phys(hyp_pgd); -} - -phys_addr_t kvm_get_idmap_vector(void) -{ - return hyp_idmap_vector; -} - -static int kvm_map_idmap_text(pgd_t *pgd) -{ - int err; - - /* Create the idmap in the boot page tables */ - err = __create_hyp_mappings(pgd, __kvm_idmap_ptrs_per_pgd(), - hyp_idmap_start, hyp_idmap_end, - __phys_to_pfn(hyp_idmap_start), - PAGE_HYP_EXEC); - if (err) - kvm_err("Failed to idmap %lx-%lx\n", - hyp_idmap_start, hyp_idmap_end); - - return err; -} - -int kvm_mmu_init(void) -{ - int err; - - hyp_idmap_start = kvm_virt_to_phys(__hyp_idmap_text_start); - hyp_idmap_start = ALIGN_DOWN(hyp_idmap_start, PAGE_SIZE); - hyp_idmap_end = kvm_virt_to_phys(__hyp_idmap_text_end); - hyp_idmap_end = ALIGN(hyp_idmap_end, PAGE_SIZE); - hyp_idmap_vector = kvm_virt_to_phys(__kvm_hyp_init); - - /* - * We rely on the linker script to ensure at build time that the HYP - * init code does not cross a page boundary. - */ - BUG_ON((hyp_idmap_start ^ (hyp_idmap_end - 1)) & PAGE_MASK); - - kvm_debug("IDMAP page: %lx\n", hyp_idmap_start); - kvm_debug("HYP VA range: %lx:%lx\n", - kern_hyp_va(PAGE_OFFSET), - kern_hyp_va((unsigned long)high_memory - 1)); - - if (hyp_idmap_start >= kern_hyp_va(PAGE_OFFSET) && - hyp_idmap_start < kern_hyp_va((unsigned long)high_memory - 1) && - hyp_idmap_start != (unsigned long)__hyp_idmap_text_start) { - /* - * The idmap page is intersecting with the VA space, - * it is not safe to continue further. - */ - kvm_err("IDMAP intersecting with HYP VA, unable to continue\n"); - err = -EINVAL; - goto out; - } - - hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order); - if (!hyp_pgd) { - kvm_err("Hyp mode PGD not allocated\n"); - err = -ENOMEM; - goto out; - } - - if (__kvm_cpu_uses_extended_idmap()) { - boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, - hyp_pgd_order); - if (!boot_hyp_pgd) { - kvm_err("Hyp boot PGD not allocated\n"); - err = -ENOMEM; - goto out; - } - - err = kvm_map_idmap_text(boot_hyp_pgd); - if (err) - goto out; - - merged_hyp_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO); - if (!merged_hyp_pgd) { - kvm_err("Failed to allocate extra HYP pgd\n"); - goto out; - } - __kvm_extend_hypmap(boot_hyp_pgd, hyp_pgd, merged_hyp_pgd, - hyp_idmap_start); - } else { - err = kvm_map_idmap_text(hyp_pgd); - if (err) - goto out; - } - - io_map_base = hyp_idmap_start; - return 0; -out: - free_hyp_pgds(); - return err; -} - -void kvm_arch_commit_memory_region(struct kvm *kvm, - const struct kvm_userspace_memory_region *mem, - struct kvm_memory_slot *old, - const struct kvm_memory_slot *new, - enum kvm_mr_change change) -{ - /* - * At this point memslot has been committed and there is an - * allocated dirty_bitmap[], dirty pages will be be tracked while the - * memory slot is write protected. - */ - if (change != KVM_MR_DELETE && mem->flags & KVM_MEM_LOG_DIRTY_PAGES) - kvm_mmu_wp_memory_region(kvm, mem->slot); -} - -int kvm_arch_prepare_memory_region(struct kvm *kvm, - struct kvm_memory_slot *memslot, - const struct kvm_userspace_memory_region *mem, - enum kvm_mr_change change) -{ - hva_t hva = mem->userspace_addr; - hva_t reg_end = hva + mem->memory_size; - bool writable = !(mem->flags & KVM_MEM_READONLY); - int ret = 0; - - if (change != KVM_MR_CREATE && change != KVM_MR_MOVE && - change != KVM_MR_FLAGS_ONLY) - return 0; - - /* - * Prevent userspace from creating a memory region outside of the IPA - * space addressable by the KVM guest IPA space. - */ - if (memslot->base_gfn + memslot->npages >= - (kvm_phys_size(kvm) >> PAGE_SHIFT)) - return -EFAULT; - - down_read(¤t->mm->mmap_sem); - /* - * A memory region could potentially cover multiple VMAs, and any holes - * between them, so iterate over all of them to find out if we can map - * any of them right now. - * - * +--------------------------------------------+ - * +---------------+----------------+ +----------------+ - * | : VMA 1 | VMA 2 | | VMA 3 : | - * +---------------+----------------+ +----------------+ - * | memory region | - * +--------------------------------------------+ - */ - do { - struct vm_area_struct *vma = find_vma(current->mm, hva); - hva_t vm_start, vm_end; - - if (!vma || vma->vm_start >= reg_end) - break; - - /* - * Take the intersection of this VMA with the memory region - */ - vm_start = max(hva, vma->vm_start); - vm_end = min(reg_end, vma->vm_end); - - if (vma->vm_flags & VM_PFNMAP) { - gpa_t gpa = mem->guest_phys_addr + - (vm_start - mem->userspace_addr); - phys_addr_t pa; - - pa = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT; - pa += vm_start - vma->vm_start; - - /* IO region dirty page logging not allowed */ - if (memslot->flags & KVM_MEM_LOG_DIRTY_PAGES) { - ret = -EINVAL; - goto out; - } - - ret = kvm_phys_addr_ioremap(kvm, gpa, pa, - vm_end - vm_start, - writable); - if (ret) - break; - } - hva = vm_end; - } while (hva < reg_end); - - if (change == KVM_MR_FLAGS_ONLY) - goto out; - - spin_lock(&kvm->mmu_lock); - if (ret) - unmap_stage2_range(kvm, mem->guest_phys_addr, mem->memory_size); - else - stage2_flush_memslot(kvm, memslot); - spin_unlock(&kvm->mmu_lock); -out: - up_read(¤t->mm->mmap_sem); - return ret; -} - -void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) -{ -} - -void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) -{ -} - -void kvm_arch_flush_shadow_all(struct kvm *kvm) -{ - kvm_free_stage2_pgd(kvm); -} - -void kvm_arch_flush_shadow_memslot(struct kvm *kvm, - struct kvm_memory_slot *slot) -{ - gpa_t gpa = slot->base_gfn << PAGE_SHIFT; - phys_addr_t size = slot->npages << PAGE_SHIFT; - - spin_lock(&kvm->mmu_lock); - unmap_stage2_range(kvm, gpa, size); - spin_unlock(&kvm->mmu_lock); -} - -/* - * See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized). - * - * Main problems: - * - S/W ops are local to a CPU (not broadcast) - * - We have line migration behind our back (speculation) - * - System caches don't support S/W at all (damn!) - * - * In the face of the above, the best we can do is to try and convert - * S/W ops to VA ops. Because the guest is not allowed to infer the - * S/W to PA mapping, it can only use S/W to nuke the whole cache, - * which is a rather good thing for us. - * - * Also, it is only used when turning caches on/off ("The expected - * usage of the cache maintenance instructions that operate by set/way - * is associated with the cache maintenance instructions associated - * with the powerdown and powerup of caches, if this is required by - * the implementation."). - * - * We use the following policy: - * - * - If we trap a S/W operation, we enable VM trapping to detect - * caches being turned on/off, and do a full clean. - * - * - We flush the caches on both caches being turned on and off. - * - * - Once the caches are enabled, we stop trapping VM ops. - */ -void kvm_set_way_flush(struct kvm_vcpu *vcpu) -{ - unsigned long hcr = *vcpu_hcr(vcpu); - - /* - * If this is the first time we do a S/W operation - * (i.e. HCR_TVM not set) flush the whole memory, and set the - * VM trapping. - * - * Otherwise, rely on the VM trapping to wait for the MMU + - * Caches to be turned off. At that point, we'll be able to - * clean the caches again. - */ - if (!(hcr & HCR_TVM)) { - trace_kvm_set_way_flush(*vcpu_pc(vcpu), - vcpu_has_cache_enabled(vcpu)); - stage2_flush_vm(vcpu->kvm); - *vcpu_hcr(vcpu) = hcr | HCR_TVM; - } -} - -void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled) -{ - bool now_enabled = vcpu_has_cache_enabled(vcpu); - - /* - * If switching the MMU+caches on, need to invalidate the caches. - * If switching it off, need to clean the caches. - * Clean + invalidate does the trick always. - */ - if (now_enabled != was_enabled) - stage2_flush_vm(vcpu->kvm); - - /* Caches are now on, stop trapping VM ops (until a S/W op) */ - if (now_enabled) - *vcpu_hcr(vcpu) &= ~HCR_TVM; - - trace_kvm_toggle_cache(*vcpu_pc(vcpu), was_enabled, now_enabled); -} |