openEuler/openEuler_kernel_rk3588
3
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
openEuler_kernel_rk3588/arch/sw_64/kvm/mmu.c

1562 lines
40 KiB
C
Raw Normal View History

init
2026-01-29 22:25:33 +08:00
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020 - os kernal
* Author: lff <lff@example.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.
*/
#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/mman.h>
#include <linux/sched/signal.h>
#include <linux/freezer.h>
#include <linux/smp.h>
#include <linux/kvm.h>
#include <linux/uaccess.h>
#include <linux/hugetlb.h>
#include <asm/kvm_asm.h>
#include <asm/sw64io.h>
#include <asm/kvm_timer.h>
#include <asm/kvm_host.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_mmu.h>
#define KVM_APT_FLAG_LOGGING_ACTIVE (1UL << 1)
static bool memslot_is_logging(struct kvm_memory_slot *memslot)
{
return memslot->dirty_bitmap && !(memslot->flags & KVM_MEM_READONLY);
}
/*
* Return values of kvm_handle_mmio_page_fault and mmu.page_fault:
* RET_AF_RETRY: let CPU fault again on the address.
* RET_AF_EMULATE: mmio page fault, emulate the instruction directly.
*
* For kvm_handle_mmio_page_fault only:
* RET_AF_INVALID: the spte is invalid, let the real page fault path update it.
*/
enum {
RET_AF_RETRY = 0,
RET_AF_EMULATE = 1,
RET_AF_INVALID = 2,
};
/**
* apt_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 TLBs.
*/
static void apt_dissolve_pmd(struct kvm *kvm, phys_addr_t addr, pmd_t *pmd)
{
int i;
if (!pmd_trans_huge(*pmd))
return;
if (pmd_trans_cont(*pmd)) {
for (i = 0; i < CONT_PMDS; i++, pmd++)
pmd_clear(pmd);
} else
pmd_clear(pmd);
kvm_flush_remote_tlbs(kvm);
put_page(virt_to_page(pmd));
}
/**
* apt_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 TLBs.
*/
static void apt_dissolve_pud(struct kvm *kvm, phys_addr_t addr, pud_t *pudp)
{
if (!pud_huge(*pudp))
return;
pud_clear(pudp);
kvm_flush_remote_tlbs(kvm);
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_KERNEL | __GFP_ZERO);
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]);
}
void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu)
{
mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
}
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 unmap_apt_ptes(struct kvm *kvm, pmd_t *pmd,
phys_addr_t addr, phys_addr_t end)
{
pte_t *pte, *start_pte;
struct page *ptr_page;
start_pte = pte = pte_offset_kernel(pmd, addr);
do {
if (!pte_none(*pte)) {
/* Do we need WRITE_ONCE(pte, 0)? */
set_pte(pte, __pte(0));
put_page(virt_to_page(pte));
}
} while (pte++, addr += PAGE_SIZE, addr != end);
ptr_page = virt_to_page(start_pte);
if (page_count(ptr_page) == 1) {
pte_t *pte_table = pte_offset_kernel(pmd, 0);
pmd_clear(pmd);
free_page((unsigned long)pte_table);
put_page(virt_to_page(pmd));
}
}
static void unmap_apt_pmds(struct kvm *kvm, pud_t *pud,
phys_addr_t addr, phys_addr_t end)
{
phys_addr_t next;
pmd_t *pmd, *start_pmd;
struct page *ptr_page;
int i;
start_pmd = pmd = pmd_offset(pud, addr);
do {
next = pmd_addr_end(addr, end);
if (!pmd_none(*pmd)) {
if (pmd_trans_huge(*pmd)) {
if (pmd_trans_cont(*pmd)) {
for (i = 0; i < CONT_PMDS; i++, pmd++)
pmd_clear(pmd);
} else
pmd_clear(pmd);
/* Do we need flush tlb???? edited by lff */
kvm_flush_remote_tlbs(kvm);
put_page(virt_to_page(pmd));
} else {
unmap_apt_ptes(kvm, pmd, addr, next);
}
}
} while (pmd++, addr = next, addr != end);
ptr_page = virt_to_page(start_pmd);
if (page_count(ptr_page) == 1) {
pmd_t *pmd_table __maybe_unused = pmd_offset(pud, 0UL);
pud_clear(pud);
free_page((unsigned long)pmd_table);
put_page(virt_to_page(pud));
}
}
static void unmap_apt_puds(struct kvm *kvm, p4d_t *p4d,
phys_addr_t addr, phys_addr_t end)
{
phys_addr_t next;
pud_t *pud, *start_pud;
struct page *ptr_page;
start_pud = pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
if (!pud_none(*pud)) {
if (pud_huge(*pud)) {
pud_clear(pud);
/* Do we need flush tlb???? edited by lff */
kvm_flush_remote_tlbs(kvm);
put_page(virt_to_page(pud));
} else {
unmap_apt_pmds(kvm, pud, addr, next);
}
}
} while (pud++, addr = next, addr != end);
ptr_page = virt_to_page(start_pud);
if (page_count(ptr_page) == 1) {
pud_t *pud_table __maybe_unused = pud_offset(p4d, 0UL);
p4d_clear(p4d);
kvm_flush_remote_tlbs(kvm);
free_page((unsigned long)pud_table);
put_page(virt_to_page(p4d));
}
}
/**
* unmap_apt_range -- Clear addtional 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 apt mappings, lowering the various ref-counts. Must
* be called while holding mmu_lock (unless for freeing the apt pgd before
* destroying the VM), otherwise another faulting VCPU may come in and mess
* with things behind our backs.
*/
static void unmap_apt_range(struct kvm *kvm, phys_addr_t start, u64 size)
{
pgd_t *pgd;
p4d_t *p4d;
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 + pgd_index(addr);
p4d = p4d_offset(pgd, 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 = p4d_addr_end(addr, end);
if (!p4d_none(*p4d))
unmap_apt_puds(kvm, p4d, 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 apt_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_apt_range(kvm, gpa, vm_end - vm_start);
}
hva = vm_end;
} while (hva < reg_end);
}
/**
* apt_unmap_vm - Unmap Additional Stage RAM mappings
* @kvm: The struct kvm pointer
*
* Go through the memregions and unmap any reguler RAM
* backing memory already mapped to the VM.
*/
void apt_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_lock);
spin_lock(&kvm->mmu_lock);
slots = kvm_memslots(kvm);
kvm_for_each_memslot(memslot, slots)
apt_unmap_memslot(kvm, memslot);
spin_unlock(&kvm->mmu_lock);
up_read(&current->mm->mmap_lock);
srcu_read_unlock(&kvm->srcu, idx);
}
static pud_t *apt_get_pud(pgd_t *pgd, struct kvm_mmu_memory_cache *cache,
phys_addr_t addr)
{
p4d_t *p4d;
pud_t *pud;
pgd += pgd_index(addr);
if (pgd_none(*pgd)) {
/* Not used on SW64 yet */
VM_BUG_ON(pgd);
return NULL;
}
p4d = p4d_offset(pgd, addr);
if (p4d_none(*p4d)) {
if (!cache)
return NULL;
pud = mmu_memory_cache_alloc(cache);
p4d_populate(NULL, p4d, pud);
get_page(virt_to_page(p4d));
}
return pud_offset(p4d, addr);
}
static pmd_t *apt_get_pmd(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
phys_addr_t addr, unsigned long sz)
{
pud_t *pud;
pmd_t *pmd;
pud = apt_get_pud(kvm->arch.pgd, cache, addr);
if (!pud || pud_huge(*pud))
return NULL;
if (pud_none(*pud)) {
if (!cache)
return NULL;
pmd = mmu_memory_cache_alloc(cache);
pud_populate(NULL, pud, pmd);
get_page(virt_to_page(pud));
}
if (sz == CONT_PMD_SIZE)
addr &= CONT_PMD_MASK;
return pmd_offset(pud, addr);
}
static bool kvm_is_write_fault(unsigned long access_type)
{
if (access_type == AF_WRITE_ACCESS_TYPE)
return true;
return false;
}
static bool kvm_is_exec_fault(unsigned long access_type)
{
if (access_type == AF_EXEC_ACCESS_TYPE)
return true;
return false;
}
/**
* apt_wp_ptes - write protect PMD range
* @pmd: pointer to pmd entry
* @addr: range start address
* @end: range end address
*/
static void apt_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_aptpte_readonly(pte))
kvm_set_aptpte_readonly(pte);
}
} while (pte++, addr += PAGE_SIZE, addr != end);
}
/**
* apt_wp_pmds - write protect PUD range
* @pud: pointer to pud entry
* @addr: range start address
* @end: range end address
*/
static void apt_wp_pmds(pud_t *pud, phys_addr_t addr, phys_addr_t end)
{
pmd_t *pmd;
phys_addr_t next;
pmd = pmd_offset(pud, addr);
do {
next = pmd_addr_end(addr, end);
if (!pmd_none(*pmd)) {
if (pmd_trans_huge(*pmd)) {
if (!kvm_aptpmd_readonly(pmd))
kvm_set_aptpmd_readonly(pmd);
} else {
apt_wp_ptes(pmd, addr, next);
}
}
} while (pmd++, addr = next, addr != end);
}
/**
* apt_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 apt_wp_puds(p4d_t *p4d, phys_addr_t addr, phys_addr_t end)
{
pud_t *pud;
phys_addr_t next;
pud = pud_offset(p4d, addr);
do {
next = pud_addr_end(addr, end);
if (!pud_none(*pud)) {
if (pud_huge(*pud)) {
if (!kvm_aptpud_readonly(pud))
kvm_set_aptpud_readonly(pud);
} else {
/* TODO:PUD not supported, revisit later if supported */
// BUG_ON(pud_trans_huge(*pud));
apt_wp_pmds(pud, addr, next);
}
}
} while (pud++, addr = next, addr != end);
}
/**
* apt_wp_range() - write protect apt memory region range
* @kvm: The KVM pointer
* @addr: Start address of range
* @end: End address of range
*/
static void apt_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
{
pgd_t *pgd;
p4d_t *p4d;
phys_addr_t next;
pgd = kvm->arch.pgd + pgd_index(addr);
p4d = p4d_offset(pgd, 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 = p4d_addr_end(addr, end);
if (p4d_present(*p4d))
apt_wp_puds(p4d, addr, next);
} while (p4d++, addr = next, addr != end);
}
/**
* kvm_mmu_wp_memory_region() - write protect apt 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);
apt_wp_range(kvm, start, end);
spin_unlock(&kvm->mmu_lock);
kvm_flush_remote_tlbs(kvm); // 需要通知其他vcpu进行tlb刷新，利用request机制
}
void kvm_mark_migration(struct kvm *kvm, int mark)
{
struct kvm_vcpu *vcpu;
unsigned long cpu;
kvm_for_each_vcpu(cpu, vcpu, kvm)
vcpu->arch.migration_mark = mark;
}
void kvm_arch_commit_memory_region(struct kvm *kvm,
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 tracked while the
* memory slot is write protected.
*/
if (change == KVM_MR_FLAGS_ONLY && (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
kvm_mark_migration(kvm, 1);
kvm_mmu_wp_memory_region(kvm, new->id);
}
/* If dirty logging has been stopped, do nothing for now. */
if ((change != KVM_MR_DELETE)
&& (old->flags & KVM_MEM_LOG_DIRTY_PAGES)
&& (!(new->flags & KVM_MEM_LOG_DIRTY_PAGES))) {
kvm_mark_migration(kvm, 0);
return;
}
}
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);
// flush_apt_tlbs(kvm);
unmap_apt_range(kvm, gpa, size);
spin_unlock(&kvm->mmu_lock);
}
/**
* kvm_alloc_addtional_stage_pgd - allocate level-1 table for addtional stage translation.
* @kvm: The KVM struct pointer for the VM.
*
* Allocates only the addtional stage HW PGD level table(s) (can support full
* 48-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_addtional_stage_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(PAGE_SIZE, GFP_KERNEL | __GFP_ZERO);
if (!pgd)
return -ENOMEM;
kvm->arch.pgd = pgd;
return 0;
}
/**
* kvm_free_apt_pgd - free all apt 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_apt_pgd(struct kvm *kvm)
{
void *pgd = NULL;
spin_lock(&kvm->mmu_lock);
if (kvm->arch.pgd) {
unmap_apt_range(kvm, 0, KVM_PHYS_SIZE);
pgd = READ_ONCE(kvm->arch.pgd);
kvm->arch.pgd = NULL;
}
spin_unlock(&kvm->mmu_lock);
/* Free the HW pgd, one page at a time */
if (pgd)
free_pages_exact(pgd, PAGE_SIZE);
}
void kvm_arch_flush_shadow_all(struct kvm *kvm)
{
kvm_free_apt_pgd(kvm);
}
static void kvm_send_hwpoison_signal(unsigned long address,
struct vm_area_struct *vma)
{
kernel_siginfo_t info;
clear_siginfo(&info);
info.si_signo = SIGBUS;
info.si_errno = 0;
info.si_code = BUS_MCEERR_AR;
info.si_addr = (void __user *)address;
if (is_vm_hugetlb_page(vma))
info.si_addr_lsb = huge_page_shift(hstate_vma(vma));
else
info.si_addr_lsb = PAGE_SHIFT;
send_sig_info(SIGBUS, &info, current);
}
static bool fault_supports_apt_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;
/* The memslot and the VMA are guaranteed to be aligned to PAGE_SIZE */
if (map_size == PAGE_SIZE)
return true;
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_SHIFT:
* +---+--------------------+--------------------+-----+
* |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;
}
/*
* apt_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 apt_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 = apt_get_pud(kvm->arch.pgd, NULL, addr);
if (!pudp || pud_none(*pudp) || !pud_present(*pudp))
return false;
if (pud_huge(*pudp)) {
*pudpp = pudp;
return true;
}
pmdp = pmd_offset(pudp, addr);
if (!pmdp || pmd_none(*pmdp) || !pmd_present(*pmdp))
return false;
if (pmd_trans_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 apt_is_exec(struct kvm *kvm, phys_addr_t addr)
{
pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
bool found;
found = apt_get_leaf_entry(kvm, addr, &pudp, &pmdp, &ptep);
if (!found)
return false;
if (pudp)
return kvm_pud_exec(pudp);
else if (pmdp)
return kvm_pmd_exec(pmdp);
else
return kvm_pte_exec(ptep);
}
static int apt_set_pte_fast(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 logging_active = flags & KVM_APT_FLAG_LOGGING_ACTIVE;
int inv_level = ((read_csr(CSR_AS_INFO)) >> AF_INV_LEVEL_SHIFT) & AF_INV_LEVEL_MASK;
unsigned long inv_hpa = read_csr(CSR_AS_INFO) & AF_ENTRY_ADDR_MASK;
VM_BUG_ON(logging_active && !cache);
if (inv_level == 1) {
pud = (pud_t *)(inv_hpa | PAGE_OFFSET);
goto find_pud;
} else if (inv_level == 2) {
pmd = (pmd_t *)(inv_hpa | PAGE_OFFSET);
goto find_pmd;
} else if (inv_level == 3) {
pte = (pte_t *)(inv_hpa | PAGE_OFFSET);
goto find_pte;
}
/* Create addtional page table mapping - Levels 0 and 1 */
pud = apt_get_pud(kvm->arch.pgd, 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)
apt_dissolve_pud(kvm, addr, pud);
find_pud:
if (pud_none(*pud)) {
if (!cache)
return 0; /* ignore calls from kvm_set_spte_hva */
pmd = mmu_memory_cache_alloc(cache);
pud_populate(NULL, pud, pmd);
get_page(virt_to_page(pud));
}
pmd = pmd_offset(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)
apt_dissolve_pmd(kvm, addr, pmd);
find_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);
find_pte:
/* Create 2nd stage page table mapping - Level 3 */
old_pte = *pte;
/* new pte should be readonly? */
// *new_pte = pte_wrprotect(*new_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;
/* Do we need WRITE_ONCE(pte, 0)? */
set_pte(pte, __pte(0));
kvm_flush_remote_tlbs(kvm);
} else {
get_page(virt_to_page(pte));
}
/* Do we need WRITE_ONCE(pte, new_pte)? */
set_pte(pte, *new_pte);
return 0;
}
static int apt_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 logging_active = flags & KVM_APT_FLAG_LOGGING_ACTIVE;
VM_BUG_ON(logging_active && !cache);
/* Create addtional page table mapping - Levels 0 and 1 */
pud = apt_get_pud(kvm->arch.pgd, 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)
apt_dissolve_pud(kvm, addr, pud);
if (pud_none(*pud)) {
if (!cache)
return 0; /* ignore calls from kvm_set_spte_hva */
pmd = mmu_memory_cache_alloc(cache);
pud_populate(NULL, pud, pmd);
get_page(virt_to_page(pud));
}
pmd = pmd_offset(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)
apt_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);
/* Create 2nd stage page table mapping - Level 3 */
old_pte = *pte;
/* new pte should be readonly? */
// *new_pte = pte_wrprotect(*new_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;
/* Do we need WRITE_ONCE(pte, 0)? */
set_pte(pte, __pte(0));
kvm_flush_remote_tlbs(kvm);
} else {
get_page(virt_to_page(pte));
}
/* Do we need WRITE_ONCE(pte, new_pte)? */
set_pte(pte, *new_pte);
return 0;
}
static int apt_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache
*cache, phys_addr_t addr, const pmd_t *new_pmd, unsigned long sz)
{
pmd_t *pmd, old_pmd, *ori_pmd;
int i;
retry:
pmd = apt_get_pmd(kvm, cache, addr, sz);
VM_BUG_ON(!pmd);
ori_pmd = pmd;
old_pmd = *pmd;
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_trans_huge(old_pmd)) {
unmap_apt_range(kvm, addr & PMD_MASK, PMD_SIZE);
goto retry;
}
/*
* 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;
/*
* 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_pfn(old_pmd) != pmd_pfn(*new_pmd));
if (sz == CONT_PMD_SIZE) {
for (i = 0; i < CONT_PMDS; i++, pmd++)
pmd_clear(pmd);
} else
pmd_clear(pmd);
kvm_flush_remote_tlbs(kvm);
} else {
get_page(virt_to_page(pmd));
}
/* Do we need WRITE_ONCE(pmd, new_pmd)? */
if (sz == CONT_PMD_SIZE) {
for (i = 0; i < CONT_PMDS; i++, ori_pmd++)
set_pmd(ori_pmd, *new_pmd);
} else
set_pmd(pmd, *new_pmd);
return 0;
}
static int apt_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 = apt_get_pud(kvm->arch.pgd, 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 (pud_present(old_pud)) {
/*
* If we already have table level mapping for this block, unmap
* the range for this block and retry.
*/
if (!pud_huge(old_pud)) {
unmap_apt_range(kvm, addr & PUD_MASK, PUD_SIZE);
goto retry;
}
// WARN_ON_ONCE(kvm_pud_pfn(old_pud) != kvm_pud_pfn(*new_pudp));
pud_clear(pudp);
kvm_flush_remote_tlbs(kvm);
} else {
get_page(virt_to_page(pudp));
}
set_pud(pudp, *new_pudp);
return 0;
}
static unsigned long
transparent_hugepage_adjust(struct kvm_memory_slot *memslot,
unsigned long hva, kvm_pfn_t *pfnp,
phys_addr_t *gpap)
{
kvm_pfn_t pfn = *pfnp;
struct page *page = pfn_to_page(pfn);
/*
* Make sure the adjustment is done only for THP pages. Also make
* sure that the HVA and IPA are sufficiently aligned and that the
* block map is contained within the memslot.
*/
if (!PageHuge(page) && PageTransCompoundMap(page) &&
fault_supports_apt_huge_mapping(memslot, hva, PMD_SIZE)) {
/*
* 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.
*/
*gpap &= PMD_MASK;
kvm_release_pfn_clean(pfn);
pfn &= ~(PTRS_PER_PMD - 1);
kvm_get_pfn(pfn);
*pfnp = pfn;
return PMD_SIZE;
}
return PAGE_SIZE;
}
static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_gpa,
struct kvm_memory_slot *memslot, unsigned long hva,
unsigned long fault_status)
{
int ret;
bool write_fault, exec_fault, writable, force_pte = false;
unsigned long mmu_seq;
gfn_t gfn = fault_gpa >> 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_READONLY;
bool logging_active = memslot_is_logging(memslot);
unsigned long vma_pagesize, flags = 0;
unsigned long as_info, access_type;
unsigned int vma_shift;
as_info = read_csr(CSR_AS_INFO);
access_type = (as_info >> AF_ACCESS_TYPE_SHIFT) & AF_ACCESS_TYPE_MASK;
write_fault = kvm_is_write_fault(access_type);
exec_fault = kvm_is_exec_fault(access_type);
VM_BUG_ON(write_fault && exec_fault);
if (fault_status == AF_STATUS_FOR) {
kvm_err("Unexpected APT 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_lock);
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_lock);
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_apt_huge_mapping(memslot, hva, vma_pagesize)) {
force_pte = true;
vma_pagesize = PAGE_SIZE;
}
if (vma_pagesize == PMD_SIZE || vma_pagesize == CONT_PMD_SIZE || vma_pagesize == PUD_SIZE)
gfn = (fault_gpa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT;
up_read(&current->mm->mmap_lock);
/* 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 (pfn == KVM_PFN_ERR_HWPOISON) {
kvm_send_hwpoison_signal(hva, vma);
return 0;
}
if (is_error_noslot_pfn(pfn))
return -EFAULT;
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_APT_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 we are not forced to use page mapping, check if we are
* backed by a THP and thus use block mapping if possible.
*/
if (vma_pagesize == PAGE_SIZE && !force_pte) {
vma_pagesize = transparent_hugepage_adjust(memslot, hva,
&pfn, &fault_gpa);
}
if (vma_pagesize == PUD_SIZE) {
pud_t new_pud = pfn_pud(pfn, mem_type);
new_pud = pud_mkhuge(new_pud);
if (writable) {
new_pud = kvm_pud_mkwrite(new_pud);
kvm_set_pfn_dirty(pfn);
}
if (exec_fault && fault_status == AF_STATUS_INV) {
new_pud = kvm_pud_mkexec(new_pud);
} else if (fault_status == AF_STATUS_FOE) {
/* Preserve execute if FOE was already cleared */
if (apt_is_exec(kvm, fault_gpa))
new_pud = kvm_pud_mkexec(new_pud);
}
ret = apt_set_pud_huge(kvm, memcache, fault_gpa, &new_pud);
} else if (vma_pagesize == CONT_PMD_SIZE) {
pmd_t new_pmd = pfn_pmd(pfn, mem_type);
new_pmd = pmd_mkhuge(new_pmd);
new_pmd = pmd_mkcont(new_pmd);
if (writable) {
new_pmd = kvm_pmd_mkwrite(new_pmd);
kvm_set_pfn_dirty(pfn);
}
if (exec_fault && fault_status == AF_STATUS_INV) {
new_pmd = kvm_pmd_mkexec(new_pmd);
} else if (fault_status == AF_STATUS_FOE) {
/* Preserve execute if FOE was already cleared */
if (apt_is_exec(kvm, fault_gpa))
new_pmd = kvm_pmd_mkexec(new_pmd);
}
ret = apt_set_pmd_huge(kvm, memcache, fault_gpa, &new_pmd, vma_pagesize);
} else if (vma_pagesize == PMD_SIZE) {
pmd_t new_pmd = pfn_pmd(pfn, mem_type);
new_pmd = pmd_mkhuge(new_pmd);
if (writable) {
new_pmd = kvm_pmd_mkwrite(new_pmd);
kvm_set_pfn_dirty(pfn);
}
if (exec_fault && fault_status == AF_STATUS_INV) {
new_pmd = kvm_pmd_mkexec(new_pmd);
} else if (fault_status == AF_STATUS_FOE) {
/* Preserve execute if FOE was already cleared */
if (apt_is_exec(kvm, fault_gpa))
new_pmd = kvm_pmd_mkexec(new_pmd);
}
ret = apt_set_pmd_huge(kvm, memcache, fault_gpa, &new_pmd, vma_pagesize);
} else {
pte_t new_pte = pfn_pte(pfn, mem_type);
if (writable) {
new_pte = kvm_pte_mkwrite(new_pte);
kvm_set_pfn_dirty(pfn);
mark_page_dirty(kvm, gfn);
}
if (exec_fault && fault_status == AF_STATUS_INV) {
new_pte = kvm_pte_mkexec(new_pte);
} else if (fault_status == AF_STATUS_FOE) {
/* Preserve execute if FOE was already cleared */
if (apt_is_exec(kvm, fault_gpa))
new_pte = kvm_pte_mkexec(new_pte);
}
ret = apt_set_pte_fast(kvm, memcache, fault_gpa, &new_pte, flags);
if (!ret)
goto out_unlock;
}
out_unlock:
spin_unlock(&kvm->mmu_lock);
kvm_set_pfn_accessed(pfn);
kvm_release_pfn_clean(pfn);
return ret;
}
/**
* 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.
*/
#ifdef CONFIG_SUBARCH_C4
int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
unsigned long as_info; /* the value of CSR: AS_INFO */
unsigned int access_type, inv_level;
unsigned int fault_status;
unsigned long fault_entry_addr;
phys_addr_t fault_gpa;
struct kvm_memory_slot *memslot;
unsigned long hva;
bool write_fault, writable;
gfn_t gfn;
int ret, idx;
as_info = read_csr(CSR_AS_INFO);
access_type = (as_info >> AF_ACCESS_TYPE_SHIFT) & AF_ACCESS_TYPE_MASK;
inv_level = (as_info >> AF_INV_LEVEL_SHIFT) & AF_INV_LEVEL_MASK;
fault_status = (as_info >> AF_FAULT_STATUS_SHIFT) & AF_FAULT_STATUS_MASK;
fault_entry_addr = (as_info & AF_ENTRY_ADDR_MASK) >> 3;
fault_gpa = read_csr(CSR_EXC_GPA);
idx = srcu_read_lock(&vcpu->kvm->srcu);
gfn = fault_gpa >> PAGE_SHIFT;
memslot = gfn_to_memslot(vcpu->kvm, gfn);
hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable);
write_fault = kvm_is_write_fault(access_type);
/* The memory slot for IO doesn't register in memory region
* with kvm, if hva == KVM_HVA_ERR_BAD, the gpa used for MMIO
* needs emulation.
*/
if (hva == KVM_HVA_ERR_BAD) {
ret = io_mem_abort(vcpu, run, NULL);
goto out_unlock;
}
/* Userspace should not be able to register out-of-bounds IPAs */
VM_BUG_ON(fault_gpa >= KVM_PHYS_SIZE);
ret = user_mem_abort(vcpu, fault_gpa, memslot, hva, fault_status);
if (ret == 0)
ret = 1;
out_unlock:
srcu_read_unlock(&vcpu->kvm->srcu, idx);
return ret;
}
#endif
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_apt_range(kvm, gpa, size);
return 0;
}
int kvm_unmap_hva_range(struct kvm *kvm,
unsigned long start, unsigned long end, bool blockable)
{
if (!kvm->arch.pgd)
return 0;
handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);
return 1;
}
static int apt_ptep_test_and_clear_young(pte_t *pte)
{
if (pte_young(*pte)) {
*pte = pte_mkold(*pte);
return 1;
}
return 0;
}
static int apt_pmdp_test_and_clear_young(pmd_t *pmd)
{
return apt_ptep_test_and_clear_young((pte_t *)pmd);
}
static int apt_pudp_test_and_clear_young(pud_t *pud)
{
return apt_ptep_test_and_clear_young((pte_t *)pud);
}
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 (!apt_get_leaf_entry(kvm, gpa, &pud, &pmd, &pte))
return 0;
if (pud)
return apt_pudp_test_and_clear_young(pud);
else if (pmd)
return apt_pmdp_test_and_clear_young(pmd);
else
return apt_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 (!apt_get_leaf_entry(kvm, gpa, &pud, &pmd, &pte))
return 0;
if (pud)
return apt_pudp_test_and_clear_young(pud);
else if (pmd)
return apt_pmdp_test_and_clear_young(pmd);
else
return apt_ptep_test_and_clear_young(pte);
}
int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end)
{
if (!kvm->arch.pgd)
return 0;
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;
return handle_hva_to_gpa(kvm, hva, hva, kvm_test_age_hva_handler, NULL);
}
static int kvm_set_apte_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
{
pte_t *pte = (pte_t *)data;
WARN_ON(size != PAGE_SIZE);
apt_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;
pte_t apt_pte;
if (!kvm->arch.pgd)
return 0;
apt_pte = pte_wrprotect(pte);
handle_hva_to_gpa(kvm, hva, end, &kvm_set_apte_handler, &apt_pte);
return 0;
}
/**
* 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;
apt_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);
}
Reference in New Issue Copy Permalink