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-rw-r--r--arch/arm/kvm/mmu.c1975
1 files changed, 0 insertions, 1975 deletions
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
deleted file mode 100644
index 313ee646480f..000000000000
--- a/arch/arm/kvm/mmu.c
+++ /dev/null
@@ -1,1975 +0,0 @@
-/*
- * Copyright (C) 2012 - Virtual Open Systems and Columbia University
- * Author: Christoffer Dall <c.dall@virtualopensystems.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2, as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- */
-
-#include <linux/mman.h>
-#include <linux/kvm_host.h>
-#include <linux/io.h>
-#include <linux/hugetlb.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_mmio.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;
-
-#define S2_PGD_SIZE (PTRS_PER_S2_PGD * sizeof(pgd_t))
-#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 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. Marks all
- * pages in the range dirty.
- */
-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));
-}
-
-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(PGALLOC_GFP);
- 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(pgd, 0UL);
- stage2_pgd_clear(pgd);
- kvm_tlb_flush_vmid_ipa(kvm, addr);
- stage2_pud_free(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(pud, 0);
- VM_BUG_ON(stage2_pud_huge(*pud));
- stage2_pud_clear(pud);
- kvm_tlb_flush_vmid_ipa(kvm, addr);
- stage2_pmd_free(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);
- pte_free_kernel(NULL, pte_table);
- put_page(virt_to_page(pmd));
-}
-
-/*
- * 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.
- */
-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(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(pud, addr);
- do {
- next = stage2_pmd_addr_end(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(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(pgd, addr);
- do {
- next = stage2_pud_addr_end(addr, end);
- if (!stage2_pud_none(*pud)) {
- if (stage2_pud_huge(*pud)) {
- pud_t old_pud = *pud;
-
- stage2_pud_clear(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(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);
- pgd = kvm->arch.pgd + stage2_pgd_index(addr);
- do {
- next = stage2_pgd_addr_end(addr, end);
- if (!stage2_pgd_none(*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(pud, addr);
- do {
- next = stage2_pmd_addr_end(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(pgd, addr);
- do {
- next = stage2_pud_addr_end(addr, end);
- if (!stage2_pud_none(*pud)) {
- if (stage2_pud_huge(*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(addr);
- do {
- next = stage2_pgd_addr_end(addr, end);
- 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 void unmap_hyp_range(pgd_t *pgdp, 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 + pgd_index(addr);
- do {
- next = pgd_addr_end(addr, end);
- if (!pgd_none(*pgd))
- unmap_hyp_puds(pgd, addr, next);
- } while (pgd++, addr = next, addr != end);
-}
-
-/**
- * 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 vmalloc range (from
- * VMALLOC_START to VMALLOC_END).
- *
- * boot_hyp_pgd should only map two pages for the init code.
- */
-void free_hyp_pgds(void)
-{
- unsigned long addr;
-
- mutex_lock(&kvm_hyp_pgd_mutex);
-
- if (boot_hyp_pgd) {
- unmap_hyp_range(boot_hyp_pgd, hyp_idmap_start, PAGE_SIZE);
- free_pages((unsigned long)boot_hyp_pgd, hyp_pgd_order);
- boot_hyp_pgd = NULL;
- }
-
- if (hyp_pgd) {
- unmap_hyp_range(hyp_pgd, hyp_idmap_start, PAGE_SIZE);
- for (addr = PAGE_OFFSET; virt_addr_valid(addr); addr += PGDIR_SIZE)
- unmap_hyp_range(hyp_pgd, kern_hyp_va(addr), PGDIR_SIZE);
- for (addr = VMALLOC_START; is_vmalloc_addr((void*)addr); addr += PGDIR_SIZE)
- unmap_hyp_range(hyp_pgd, kern_hyp_va(addr), PGDIR_SIZE);
-
- 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, pfn_pte(pfn, prot));
- get_page(virt_to_page(pte));
- kvm_flush_dcache_to_poc(pte, sizeof(*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, addr);
- if (!pte) {
- kvm_err("Cannot allocate Hyp pte\n");
- return -ENOMEM;
- }
- pmd_populate_kernel(NULL, pmd, pte);
- get_page(virt_to_page(pmd));
- kvm_flush_dcache_to_poc(pmd, sizeof(*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;
- }
- pud_populate(NULL, pud, pmd);
- get_page(virt_to_page(pud));
- kvm_flush_dcache_to_poc(pud, sizeof(*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 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 + pgd_index(addr);
-
- if (pgd_none(*pgd)) {
- pud = pud_alloc_one(NULL, addr);
- if (!pud) {
- kvm_err("Cannot allocate Hyp pud\n");
- err = -ENOMEM;
- goto out;
- }
- pgd_populate(NULL, pgd, pud);
- get_page(virt_to_page(pgd));
- kvm_flush_dcache_to_poc(pgd, sizeof(*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, virt_addr,
- virt_addr + PAGE_SIZE,
- __phys_to_pfn(phys_addr),
- prot);
- if (err)
- return err;
- }
-
- return 0;
-}
-
-/**
- * create_hyp_io_mappings - duplicate a kernel IO mapping into Hyp mode
- * @from: The kernel start VA of the range
- * @to: The kernel end VA of the range (exclusive)
- * @phys_addr: The physical start address which gets mapped
- *
- * The resulting HYP VA is the same as the kernel VA, modulo
- * HYP_PAGE_OFFSET.
- */
-int create_hyp_io_mappings(void *from, void *to, phys_addr_t phys_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;
-
- /* Check for a valid kernel IO mapping */
- if (!is_vmalloc_addr(from) || !is_vmalloc_addr(to - 1))
- return -EINVAL;
-
- return __create_hyp_mappings(hyp_pgd, start, end,
- __phys_to_pfn(phys_addr), PAGE_HYP_DEVICE);
-}
-
-/**
- * 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) (can support either full
- * 40-bit input addresses or limited to 32-bit input addresses). Clears the
- * allocated pages.
- *
- * 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)
-{
- 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(S2_PGD_SIZE, GFP_KERNEL | __GFP_ZERO);
- if (!pgd)
- return -ENOMEM;
-
- kvm->arch.pgd = pgd;
- 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(&current->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(&current->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.
- *
- * Note we don't need locking here as this is only called when the VM is
- * destroyed, which can only be done once.
- */
-void kvm_free_stage2_pgd(struct kvm *kvm)
-{
- if (kvm->arch.pgd == NULL)
- return;
-
- spin_lock(&kvm->mmu_lock);
- unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE);
- spin_unlock(&kvm->mmu_lock);
-
- /* Free the HW pgd, one page at a time */
- free_pages_exact(kvm->arch.pgd, S2_PGD_SIZE);
- kvm->arch.pgd = NULL;
-}
-
-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(addr);
- if (WARN_ON(stage2_pgd_none(*pgd))) {
- if (!cache)
- return NULL;
- pud = mmu_memory_cache_alloc(cache);
- stage2_pgd_populate(pgd, pud);
- get_page(virt_to_page(pgd));
- }
-
- return stage2_pud_offset(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 (stage2_pud_none(*pud)) {
- if (!cache)
- return NULL;
- pmd = mmu_memory_cache_alloc(cache);
- stage2_pud_populate(pud, pmd);
- get_page(virt_to_page(pud));
- }
-
- return stage2_pmd_offset(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;
-
- pmd = stage2_get_pmd(kvm, cache, addr);
- VM_BUG_ON(!pmd);
-
- /*
- * 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.
- */
- VM_BUG_ON(pmd_present(*pmd) && pmd_pfn(*pmd) != pmd_pfn(*new_pmd));
-
- old_pmd = *pmd;
- if (pmd_present(old_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_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
- phys_addr_t addr, const pte_t *new_pte,
- unsigned long flags)
-{
- 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 */
- pmd = stage2_get_pmd(kvm, cache, 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);
- pmd_populate_kernel(NULL, 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)) {
- 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);
-}
-
-/**
- * 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 = 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_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 (PageTransCompoundMap(pfn_to_page(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;
-}
-
-static bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
-{
- if (kvm_vcpu_trap_is_iabt(vcpu))
- return false;
-
- return kvm_vcpu_dabt_iswrite(vcpu);
-}
-
-/**
- * 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
- * @pud: pointer to pud entry
- * @addr: range start address
- * @end: range end address
- */
-static void stage2_wp_pmds(pud_t *pud, phys_addr_t addr, phys_addr_t end)
-{
- pmd_t *pmd;
- phys_addr_t next;
-
- pmd = stage2_pmd_offset(pud, addr);
-
- do {
- next = stage2_pmd_addr_end(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
- *
- * Process PUD entries, for a huge PUD we cause a panic.
- */
-static void stage2_wp_puds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end)
-{
- pud_t *pud;
- phys_addr_t next;
-
- pud = stage2_pud_offset(pgd, addr);
- do {
- next = stage2_pud_addr_end(addr, end);
- if (!stage2_pud_none(*pud)) {
- /* TODO:PUD not supported, revisit later if supported */
- BUG_ON(stage2_pud_huge(*pud));
- stage2_wp_pmds(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(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.
- */
- if (need_resched() || spin_needbreak(&kvm->mmu_lock))
- cond_resched_lock(&kvm->mmu_lock);
-
- next = stage2_pgd_addr_end(addr, end);
- if (stage2_pgd_present(*pgd))
- stage2_wp_puds(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 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 = memslot->base_gfn << PAGE_SHIFT;
- phys_addr_t 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 coherent_cache_guest_page(struct kvm_vcpu *vcpu, kvm_pfn_t pfn,
- unsigned long size)
-{
- __coherent_cache_guest_page(vcpu, pfn, size);
-}
-
-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, hugetlb = false, force_pte = false;
- 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;
- kvm_pfn_t pfn;
- pgprot_t mem_type = PAGE_S2;
- bool logging_active = memslot_is_logging(memslot);
- unsigned long flags = 0;
-
- write_fault = kvm_is_write_fault(vcpu);
- if (fault_status == FSC_PERM && !write_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(&current->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(&current->mm->mmap_sem);
- return -EFAULT;
- }
-
- if (is_vm_hugetlb_page(vma) && !logging_active) {
- hugetlb = true;
- gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT;
- } else {
- /*
- * Pages belonging to memslots that don't have the same
- * alignment for userspace and IPA cannot be mapped using
- * block descriptors even if the pages belong to a THP for
- * the process, because the stage-2 block descriptor will
- * cover more than a single THP and we loose atomicity for
- * unmapping, updates, and splits of the THP or other pages
- * in the stage-2 block range.
- */
- if ((memslot->userspace_addr & ~PMD_MASK) !=
- ((memslot->base_gfn << PAGE_SHIFT) & ~PMD_MASK))
- force_pte = true;
- }
- up_read(&current->mm->mmap_sem);
-
- /* We need minimum second+third level pages */
- ret = mmu_topup_memory_cache(memcache, KVM_MMU_CACHE_MIN_PAGES,
- 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 (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.
- */
- force_pte = true;
- flags |= KVM_S2_FLAG_LOGGING_ACTIVE;
-
- /*
- * Only actually map the page as writable if this was a write
- * fault.
- */
- if (!write_fault)
- writable = false;
- }
-
- spin_lock(&kvm->mmu_lock);
- if (mmu_notifier_retry(kvm, mmu_seq))
- goto out_unlock;
-
- if (!hugetlb && !force_pte)
- hugetlb = transparent_hugepage_adjust(&pfn, &fault_ipa);
-
- if (hugetlb) {
- pmd_t new_pmd = pfn_pmd(pfn, mem_type);
- new_pmd = pmd_mkhuge(new_pmd);
- if (writable) {
- new_pmd = kvm_s2pmd_mkwrite(new_pmd);
- kvm_set_pfn_dirty(pfn);
- }
- coherent_cache_guest_page(vcpu, pfn, PMD_SIZE);
- ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd);
- } else {
- pte_t new_pte = pfn_pte(pfn, mem_type);
-
- if (writable) {
- new_pte = kvm_s2pte_mkwrite(new_pte);
- kvm_set_pfn_dirty(pfn);
- mark_page_dirty(kvm, gfn);
- }
- coherent_cache_guest_page(vcpu, pfn, PAGE_SIZE);
- 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)
-{
- 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);
-
- pmd = stage2_get_pmd(vcpu->kvm, NULL, fault_ipa);
- if (!pmd || pmd_none(*pmd)) /* Nothing there */
- goto out;
-
- if (pmd_thp_or_huge(*pmd)) { /* THP, HugeTLB */
- *pmd = pmd_mkyoung(*pmd);
- pfn = pmd_pfn(*pmd);
- pfn_valid = true;
- goto out;
- }
-
- pte = pte_offset_kernel(pmd, fault_ipa);
- if (pte_none(*pte)) /* Nothing there either */
- goto out;
-
- *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;
-
- is_iabt = kvm_vcpu_trap_is_iabt(vcpu);
- if (unlikely(!is_iabt && kvm_vcpu_dabt_isextabt(vcpu))) {
- kvm_inject_vabt(vcpu);
- return 1;
- }
-
- fault_ipa = kvm_vcpu_get_fault_ipa(vcpu);
-
- 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 */
- fault_status = kvm_vcpu_trap_get_fault_type(vcpu);
- 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 */
- kvm_inject_pabt(vcpu, kvm_vcpu_get_hfar(vcpu));
- ret = 1;
- goto out_unlock;
- }
-
- /*
- * 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);
-
- 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_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(struct kvm *kvm, unsigned long hva)
-{
- unsigned long end = hva + PAGE_SIZE;
-
- if (!kvm->arch.pgd)
- return 0;
-
- trace_kvm_unmap_hva(hva);
- handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler, NULL);
- 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;
-}
-
-
-void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
-{
- unsigned long end = hva + PAGE_SIZE;
- pte_t stage2_pte;
-
- if (!kvm->arch.pgd)
- return;
-
- trace_kvm_set_spte_hva(hva);
- stage2_pte = pfn_pte(pte_pfn(pte), PAGE_S2);
- handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte);
-}
-
-static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
-{
- pmd_t *pmd;
- pte_t *pte;
-
- WARN_ON(size != PAGE_SIZE && size != PMD_SIZE);
- pmd = stage2_get_pmd(kvm, NULL, gpa);
- if (!pmd || pmd_none(*pmd)) /* Nothing there */
- return 0;
-
- if (pmd_thp_or_huge(*pmd)) /* THP, HugeTLB */
- return stage2_pmdp_test_and_clear_young(pmd);
-
- pte = pte_offset_kernel(pmd, gpa);
- if (pte_none(*pte))
- return 0;
-
- 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)
-{
- pmd_t *pmd;
- pte_t *pte;
-
- WARN_ON(size != PAGE_SIZE && size != PMD_SIZE);
- pmd = stage2_get_pmd(kvm, NULL, gpa);
- if (!pmd || pmd_none(*pmd)) /* Nothing there */
- return 0;
-
- if (pmd_thp_or_huge(*pmd)) /* THP, HugeTLB */
- return pmd_young(*pmd);
-
- pte = pte_offset_kernel(pmd, gpa);
- if (!pte_none(*pte)) /* Just a page... */
- return pte_young(*pte);
-
- return 0;
-}
-
-int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end)
-{
- 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)
-{
- trace_kvm_test_age_hva(hva);
- return handle_hva_to_gpa(kvm, hva, hva, 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,
- 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_end = kvm_virt_to_phys(__hyp_idmap_text_end);
- 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_info("IDMAP page: %lx\n", hyp_idmap_start);
- kvm_info("HYP VA range: %lx:%lx\n",
- kern_hyp_va(PAGE_OFFSET), kern_hyp_va(~0UL));
-
- if (hyp_idmap_start >= kern_hyp_va(PAGE_OFFSET) &&
- hyp_idmap_start < kern_hyp_va(~0UL) &&
- 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;
- }
-
- return 0;
-out:
- free_hyp_pgds();
- return err;
-}
-
-void kvm_arch_commit_memory_region(struct kvm *kvm,
- const struct kvm_userspace_memory_region *mem,
- const 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 >> PAGE_SHIFT))
- return -EFAULT;
-
- down_read(&current->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;
-
- /*
- * Mapping a read-only VMA is only allowed if the
- * memory region is configured as read-only.
- */
- if (writable && !(vma->vm_flags & VM_WRITE)) {
- ret = -EPERM;
- 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(&current->mm->mmap_sem);
- return ret;
-}
-
-void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
- struct kvm_memory_slot *dont)
-{
-}
-
-int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
- unsigned long npages)
-{
- return 0;
-}
-
-void kvm_arch_memslots_updated(struct kvm *kvm, struct kvm_memslots *slots)
-{
-}
-
-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_get_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_set_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_set_hcr(vcpu, vcpu_get_hcr(vcpu) & ~HCR_TVM);
-
- trace_kvm_toggle_cache(*vcpu_pc(vcpu), was_enabled, now_enabled);
-}
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-28 13:14:15 +0300