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qemu / qemu / f87e4d6d43d7020783d18d8657b4f9c21f9e3427 / . / softmmu / physmem.c
blob: efaed36773c1689417b67e6e329b3c9f5c18c9c0 [file] [log] [blame]
/*
* RAM allocation and memory access
*
* Copyright (c) 2003 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "exec/page-vary.h"
#include "qapi/error.h"
#include "qemu/cutils.h"
#include "qemu/cacheflush.h"
#include "qemu/hbitmap.h"
#include "qemu/madvise.h"
#ifdef CONFIG_TCG
#include "hw/core/tcg-cpu-ops.h"
#endif /* CONFIG_TCG */
#include "exec/exec-all.h"
#include "exec/target_page.h"
#include "hw/qdev-core.h"
#include "hw/qdev-properties.h"
#include "hw/boards.h"
#include "hw/xen/xen.h"
#include "sysemu/kvm.h"
#include "sysemu/tcg.h"
#include "sysemu/qtest.h"
#include "qemu/timer.h"
#include "qemu/config-file.h"
#include "qemu/error-report.h"
#include "qemu/qemu-print.h"
#include "qemu/log.h"
#include "qemu/memalign.h"
#include "exec/memory.h"
#include "exec/ioport.h"
#include "sysemu/dma.h"
#include "sysemu/hostmem.h"
#include "sysemu/hw_accel.h"
#include "sysemu/xen-mapcache.h"
#include "trace/trace-root.h"
#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
#include <linux/falloc.h>
#endif
#include "qemu/rcu_queue.h"
#include "qemu/main-loop.h"
#include "exec/translate-all.h"
#include "sysemu/replay.h"
#include "exec/memory-internal.h"
#include "exec/ram_addr.h"
#include "qemu/pmem.h"
#include "migration/vmstate.h"
#include "qemu/range.h"
#ifndef _WIN32
#include "qemu/mmap-alloc.h"
#endif
#include "monitor/monitor.h"
#ifdef CONFIG_LIBDAXCTL
#include <daxctl/libdaxctl.h>
#endif
//#define DEBUG_SUBPAGE
/* ram_list is read under rcu_read_lock()/rcu_read_unlock(). Writes
* are protected by the ramlist lock.
*/
RAMList ram_list = { .blocks = QLIST_HEAD_INITIALIZER(ram_list.blocks) };
static MemoryRegion *system_memory;
static MemoryRegion *system_io;
AddressSpace address_space_io;
AddressSpace address_space_memory;
static MemoryRegion io_mem_unassigned;
typedef struct PhysPageEntry PhysPageEntry;
struct PhysPageEntry {
/* How many bits skip to next level (in units of L2_SIZE). 0 for a leaf. */
uint32_t skip : 6;
/* index into phys_sections (!skip) or phys_map_nodes (skip) */
uint32_t ptr : 26;
};
#define PHYS_MAP_NODE_NIL (((uint32_t)~0) >> 6)
/* Size of the L2 (and L3, etc) page tables. */
#define ADDR_SPACE_BITS 64
#define P_L2_BITS 9
#define P_L2_SIZE (1 << P_L2_BITS)
#define P_L2_LEVELS (((ADDR_SPACE_BITS - TARGET_PAGE_BITS - 1) / P_L2_BITS) + 1)
typedef PhysPageEntry Node[P_L2_SIZE];
typedef struct PhysPageMap {
struct rcu_head rcu;
unsigned sections_nb;
unsigned sections_nb_alloc;
unsigned nodes_nb;
unsigned nodes_nb_alloc;
Node *nodes;
MemoryRegionSection *sections;
} PhysPageMap;
struct AddressSpaceDispatch {
MemoryRegionSection *mru_section;
/* This is a multi-level map on the physical address space.
* The bottom level has pointers to MemoryRegionSections.
*/
PhysPageEntry phys_map;
PhysPageMap map;
};
#define SUBPAGE_IDX(addr) ((addr) & ~TARGET_PAGE_MASK)
typedef struct subpage_t {
MemoryRegion iomem;
FlatView *fv;
hwaddr base;
uint16_t sub_section[];
} subpage_t;
#define PHYS_SECTION_UNASSIGNED 0
static void io_mem_init(void);
static void memory_map_init(void);
static void tcg_log_global_after_sync(MemoryListener *listener);
static void tcg_commit(MemoryListener *listener);
/**
* CPUAddressSpace: all the information a CPU needs about an AddressSpace
* @cpu: the CPU whose AddressSpace this is
* @as: the AddressSpace itself
* @memory_dispatch: its dispatch pointer (cached, RCU protected)
* @tcg_as_listener: listener for tracking changes to the AddressSpace
*/
struct CPUAddressSpace {
CPUState *cpu;
AddressSpace *as;
struct AddressSpaceDispatch *memory_dispatch;
MemoryListener tcg_as_listener;
};
struct DirtyBitmapSnapshot {
ram_addr_t start;
ram_addr_t end;
unsigned long dirty[];
};
static void phys_map_node_reserve(PhysPageMap *map, unsigned nodes)
{
static unsigned alloc_hint = 16;
if (map->nodes_nb + nodes > map->nodes_nb_alloc) {
map->nodes_nb_alloc = MAX(alloc_hint, map->nodes_nb + nodes);
map->nodes = g_renew(Node, map->nodes, map->nodes_nb_alloc);
alloc_hint = map->nodes_nb_alloc;
}
}
static uint32_t phys_map_node_alloc(PhysPageMap *map, bool leaf)
{
unsigned i;
uint32_t ret;
PhysPageEntry e;
PhysPageEntry *p;
ret = map->nodes_nb++;
p = map->nodes[ret];
assert(ret != PHYS_MAP_NODE_NIL);
assert(ret != map->nodes_nb_alloc);
e.skip = leaf ? 0 : 1;
e.ptr = leaf ? PHYS_SECTION_UNASSIGNED : PHYS_MAP_NODE_NIL;
for (i = 0; i < P_L2_SIZE; ++i) {
memcpy(&p[i], &e, sizeof(e));
}
return ret;
}
static void phys_page_set_level(PhysPageMap *map, PhysPageEntry *lp,
hwaddr *index, uint64_t *nb, uint16_t leaf,
int level)
{
PhysPageEntry *p;
hwaddr step = (hwaddr)1 << (level * P_L2_BITS);
if (lp->skip && lp->ptr == PHYS_MAP_NODE_NIL) {
lp->ptr = phys_map_node_alloc(map, level == 0);
}
p = map->nodes[lp->ptr];
lp = &p[(*index >> (level * P_L2_BITS)) & (P_L2_SIZE - 1)];
while (*nb && lp < &p[P_L2_SIZE]) {
if ((*index & (step - 1)) == 0 && *nb >= step) {
lp->skip = 0;
lp->ptr = leaf;
*index += step;
*nb -= step;
} else {
phys_page_set_level(map, lp, index, nb, leaf, level - 1);
}
++lp;
}
}
static void phys_page_set(AddressSpaceDispatch *d,
hwaddr index, uint64_t nb,
uint16_t leaf)
{
/* Wildly overreserve - it doesn't matter much. */
phys_map_node_reserve(&d->map, 3 * P_L2_LEVELS);
phys_page_set_level(&d->map, &d->phys_map, &index, &nb, leaf, P_L2_LEVELS - 1);
}
/* Compact a non leaf page entry. Simply detect that the entry has a single child,
* and update our entry so we can skip it and go directly to the destination.
*/
static void phys_page_compact(PhysPageEntry *lp, Node *nodes)
{
unsigned valid_ptr = P_L2_SIZE;
int valid = 0;
PhysPageEntry *p;
int i;
if (lp->ptr == PHYS_MAP_NODE_NIL) {
return;
}
p = nodes[lp->ptr];
for (i = 0; i < P_L2_SIZE; i++) {
if (p[i].ptr == PHYS_MAP_NODE_NIL) {
continue;
}
valid_ptr = i;
valid++;
if (p[i].skip) {
phys_page_compact(&p[i], nodes);
}
}
/* We can only compress if there's only one child. */
if (valid != 1) {
return;
}
assert(valid_ptr < P_L2_SIZE);
/* Don't compress if it won't fit in the # of bits we have. */
if (P_L2_LEVELS >= (1 << 6) &&
lp->skip + p[valid_ptr].skip >= (1 << 6)) {
return;
}
lp->ptr = p[valid_ptr].ptr;
if (!p[valid_ptr].skip) {
/* If our only child is a leaf, make this a leaf. */
/* By design, we should have made this node a leaf to begin with so we
* should never reach here.
* But since it's so simple to handle this, let's do it just in case we
* change this rule.
*/
lp->skip = 0;
} else {
lp->skip += p[valid_ptr].skip;
}
}
void address_space_dispatch_compact(AddressSpaceDispatch *d)
{
if (d->phys_map.skip) {
phys_page_compact(&d->phys_map, d->map.nodes);
}
}
static inline bool section_covers_addr(const MemoryRegionSection *section,
hwaddr addr)
{
/* Memory topology clips a memory region to [0, 2^64); size.hi > 0 means
* the section must cover the entire address space.
*/
return int128_gethi(section->size) ||
range_covers_byte(section->offset_within_address_space,
int128_getlo(section->size), addr);
}
static MemoryRegionSection *phys_page_find(AddressSpaceDispatch *d, hwaddr addr)
{
PhysPageEntry lp = d->phys_map, *p;
Node *nodes = d->map.nodes;
MemoryRegionSection *sections = d->map.sections;
hwaddr index = addr >> TARGET_PAGE_BITS;
int i;
for (i = P_L2_LEVELS; lp.skip && (i -= lp.skip) >= 0;) {
if (lp.ptr == PHYS_MAP_NODE_NIL) {
return &sections[PHYS_SECTION_UNASSIGNED];
}
p = nodes[lp.ptr];
lp = p[(index >> (i * P_L2_BITS)) & (P_L2_SIZE - 1)];
}
if (section_covers_addr(&sections[lp.ptr], addr)) {
return &sections[lp.ptr];
} else {
return &sections[PHYS_SECTION_UNASSIGNED];
}
}
/* Called from RCU critical section */
static MemoryRegionSection *address_space_lookup_region(AddressSpaceDispatch *d,
hwaddr addr,
bool resolve_subpage)
{
MemoryRegionSection *section = qatomic_read(&d->mru_section);
subpage_t *subpage;
if (!section || section == &d->map.sections[PHYS_SECTION_UNASSIGNED] ||
!section_covers_addr(section, addr)) {
section = phys_page_find(d, addr);
qatomic_set(&d->mru_section, section);
}
if (resolve_subpage && section->mr->subpage) {
subpage = container_of(section->mr, subpage_t, iomem);
section = &d->map.sections[subpage->sub_section[SUBPAGE_IDX(addr)]];
}
return section;
}
/* Called from RCU critical section */
static MemoryRegionSection *
address_space_translate_internal(AddressSpaceDispatch *d, hwaddr addr, hwaddr *xlat,
hwaddr *plen, bool resolve_subpage)
{
MemoryRegionSection *section;
MemoryRegion *mr;
Int128 diff;
section = address_space_lookup_region(d, addr, resolve_subpage);
/* Compute offset within MemoryRegionSection */
addr -= section->offset_within_address_space;
/* Compute offset within MemoryRegion */
*xlat = addr + section->offset_within_region;
mr = section->mr;
/* MMIO registers can be expected to perform full-width accesses based only
* on their address, without considering adjacent registers that could
* decode to completely different MemoryRegions. When such registers
* exist (e.g. I/O ports 0xcf8 and 0xcf9 on most PC chipsets), MMIO
* regions overlap wildly. For this reason we cannot clamp the accesses
* here.
*
* If the length is small (as is the case for address_space_ldl/stl),
* everything works fine. If the incoming length is large, however,
* the caller really has to do the clamping through memory_access_size.
*/
if (memory_region_is_ram(mr)) {
diff = int128_sub(section->size, int128_make64(addr));
*plen = int128_get64(int128_min(diff, int128_make64(*plen)));
}
return section;
}
/**
* address_space_translate_iommu - translate an address through an IOMMU
* memory region and then through the target address space.
*
* @iommu_mr: the IOMMU memory region that we start the translation from
* @addr: the address to be translated through the MMU
* @xlat: the translated address offset within the destination memory region.
* It cannot be %NULL.
* @plen_out: valid read/write length of the translated address. It
* cannot be %NULL.
* @page_mask_out: page mask for the translated address. This
* should only be meaningful for IOMMU translated
* addresses, since there may be huge pages that this bit
* would tell. It can be %NULL if we don't care about it.
* @is_write: whether the translation operation is for write
* @is_mmio: whether this can be MMIO, set true if it can
* @target_as: the address space targeted by the IOMMU
* @attrs: transaction attributes
*
* This function is called from RCU critical section. It is the common
* part of flatview_do_translate and address_space_translate_cached.
*/
static MemoryRegionSection address_space_translate_iommu(IOMMUMemoryRegion *iommu_mr,
hwaddr *xlat,
hwaddr *plen_out,
hwaddr *page_mask_out,
bool is_write,
bool is_mmio,
AddressSpace **target_as,
MemTxAttrs attrs)
{
MemoryRegionSection *section;
hwaddr page_mask = (hwaddr)-1;
do {
hwaddr addr = *xlat;
IOMMUMemoryRegionClass *imrc = memory_region_get_iommu_class_nocheck(iommu_mr);
int iommu_idx = 0;
IOMMUTLBEntry iotlb;
if (imrc->attrs_to_index) {
iommu_idx = imrc->attrs_to_index(iommu_mr, attrs);
}
iotlb = imrc->translate(iommu_mr, addr, is_write ?
IOMMU_WO : IOMMU_RO, iommu_idx);
if (!(iotlb.perm & (1 << is_write))) {
goto unassigned;
}
addr = ((iotlb.translated_addr & ~iotlb.addr_mask)
| (addr & iotlb.addr_mask));
page_mask &= iotlb.addr_mask;
*plen_out = MIN(*plen_out, (addr | iotlb.addr_mask) - addr + 1);
*target_as = iotlb.target_as;
section = address_space_translate_internal(
address_space_to_dispatch(iotlb.target_as), addr, xlat,
plen_out, is_mmio);
iommu_mr = memory_region_get_iommu(section->mr);
} while (unlikely(iommu_mr));
if (page_mask_out) {
*page_mask_out = page_mask;
}
return *section;
unassigned:
return (MemoryRegionSection) { .mr = &io_mem_unassigned };
}
/**
* flatview_do_translate - translate an address in FlatView
*
* @fv: the flat view that we want to translate on
* @addr: the address to be translated in above address space
* @xlat: the translated address offset within memory region. It
* cannot be @NULL.
* @plen_out: valid read/write length of the translated address. It
* can be @NULL when we don't care about it.
* @page_mask_out: page mask for the translated address. This
* should only be meaningful for IOMMU translated
* addresses, since there may be huge pages that this bit
* would tell. It can be @NULL if we don't care about it.
* @is_write: whether the translation operation is for write
* @is_mmio: whether this can be MMIO, set true if it can
* @target_as: the address space targeted by the IOMMU
* @attrs: memory transaction attributes
*
* This function is called from RCU critical section
*/
static MemoryRegionSection flatview_do_translate(FlatView *fv,
hwaddr addr,
hwaddr *xlat,
hwaddr *plen_out,
hwaddr *page_mask_out,
bool is_write,
bool is_mmio,
AddressSpace **target_as,
MemTxAttrs attrs)
{
MemoryRegionSection *section;
IOMMUMemoryRegion *iommu_mr;
hwaddr plen = (hwaddr)(-1);
if (!plen_out) {
plen_out = &plen;
}
section = address_space_translate_internal(
flatview_to_dispatch(fv), addr, xlat,
plen_out, is_mmio);
iommu_mr = memory_region_get_iommu(section->mr);
if (unlikely(iommu_mr)) {
return address_space_translate_iommu(iommu_mr, xlat,
plen_out, page_mask_out,
is_write, is_mmio,
target_as, attrs);
}
if (page_mask_out) {
/* Not behind an IOMMU, use default page size. */
*page_mask_out = ~TARGET_PAGE_MASK;
}
return *section;
}
/* Called from RCU critical section */
IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
bool is_write, MemTxAttrs attrs)
{
MemoryRegionSection section;
hwaddr xlat, page_mask;
/*
* This can never be MMIO, and we don't really care about plen,
* but page mask.
*/
section = flatview_do_translate(address_space_to_flatview(as), addr, &xlat,
NULL, &page_mask, is_write, false, &as,
attrs);
/* Illegal translation */
if (section.mr == &io_mem_unassigned) {
goto iotlb_fail;
}
/* Convert memory region offset into address space offset */
xlat += section.offset_within_address_space -
section.offset_within_region;
return (IOMMUTLBEntry) {
.target_as = as,
.iova = addr & ~page_mask,
.translated_addr = xlat & ~page_mask,
.addr_mask = page_mask,
/* IOTLBs are for DMAs, and DMA only allows on RAMs. */
.perm = IOMMU_RW,
};
iotlb_fail:
return (IOMMUTLBEntry) {0};
}
/* Called from RCU critical section */
MemoryRegion *flatview_translate(FlatView *fv, hwaddr addr, hwaddr *xlat,
hwaddr *plen, bool is_write,
MemTxAttrs attrs)
{
MemoryRegion *mr;
MemoryRegionSection section;
AddressSpace *as = NULL;
/* This can be MMIO, so setup MMIO bit. */
section = flatview_do_translate(fv, addr, xlat, plen, NULL,
is_write, true, &as, attrs);
mr = section.mr;
if (xen_enabled() && memory_access_is_direct(mr, is_write)) {
hwaddr page = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - addr;
*plen = MIN(page, *plen);
}
return mr;
}
typedef struct TCGIOMMUNotifier {
IOMMUNotifier n;
MemoryRegion *mr;
CPUState *cpu;
int iommu_idx;
bool active;
} TCGIOMMUNotifier;
static void tcg_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
{
TCGIOMMUNotifier *notifier = container_of(n, TCGIOMMUNotifier, n);
if (!notifier->active) {
return;
}
tlb_flush(notifier->cpu);
notifier->active = false;
/* We leave the notifier struct on the list to avoid reallocating it later.
* Generally the number of IOMMUs a CPU deals with will be small.
* In any case we can't unregister the iommu notifier from a notify
* callback.
*/
}
static void tcg_register_iommu_notifier(CPUState *cpu,
IOMMUMemoryRegion *iommu_mr,
int iommu_idx)
{
/* Make sure this CPU has an IOMMU notifier registered for this
* IOMMU/IOMMU index combination, so that we can flush its TLB
* when the IOMMU tells us the mappings we've cached have changed.
*/
MemoryRegion *mr = MEMORY_REGION(iommu_mr);
TCGIOMMUNotifier *notifier = NULL;
int i;
for (i = 0; i < cpu->iommu_notifiers->len; i++) {
notifier = g_array_index(cpu->iommu_notifiers, TCGIOMMUNotifier *, i);
if (notifier->mr == mr && notifier->iommu_idx == iommu_idx) {
break;
}
}
if (i == cpu->iommu_notifiers->len) {
/* Not found, add a new entry at the end of the array */
cpu->iommu_notifiers = g_array_set_size(cpu->iommu_notifiers, i + 1);
notifier = g_new0(TCGIOMMUNotifier, 1);
g_array_index(cpu->iommu_notifiers, TCGIOMMUNotifier *, i) = notifier;
notifier->mr = mr;
notifier->iommu_idx = iommu_idx;
notifier->cpu = cpu;
/* Rather than trying to register interest in the specific part
* of the iommu's address space that we've accessed and then
* expand it later as subsequent accesses touch more of it, we
* just register interest in the whole thing, on the assumption
* that iommu reconfiguration will be rare.
*/
iommu_notifier_init(&notifier->n,
tcg_iommu_unmap_notify,
IOMMU_NOTIFIER_UNMAP,
0,
HWADDR_MAX,
iommu_idx);
memory_region_register_iommu_notifier(notifier->mr, &notifier->n,
&error_fatal);
}
if (!notifier->active) {
notifier->active = true;
}
}
void tcg_iommu_free_notifier_list(CPUState *cpu)
{
/* Destroy the CPU's notifier list */
int i;
TCGIOMMUNotifier *notifier;
for (i = 0; i < cpu->iommu_notifiers->len; i++) {
notifier = g_array_index(cpu->iommu_notifiers, TCGIOMMUNotifier *, i);
memory_region_unregister_iommu_notifier(notifier->mr, &notifier->n);
g_free(notifier);
}
g_array_free(cpu->iommu_notifiers, true);
}
void tcg_iommu_init_notifier_list(CPUState *cpu)
{
cpu->iommu_notifiers = g_array_new(false, true, sizeof(TCGIOMMUNotifier *));
}
/* Called from RCU critical section */
MemoryRegionSection *
address_space_translate_for_iotlb(CPUState *cpu, int asidx, hwaddr orig_addr,
hwaddr *xlat, hwaddr *plen,
MemTxAttrs attrs, int *prot)
{
MemoryRegionSection *section;
IOMMUMemoryRegion *iommu_mr;
IOMMUMemoryRegionClass *imrc;
IOMMUTLBEntry iotlb;
int iommu_idx;
hwaddr addr = orig_addr;
AddressSpaceDispatch *d =
qatomic_rcu_read(&cpu->cpu_ases[asidx].memory_dispatch);
for (;;) {
section = address_space_translate_internal(d, addr, &addr, plen, false);
iommu_mr = memory_region_get_iommu(section->mr);
if (!iommu_mr) {
break;
}
imrc = memory_region_get_iommu_class_nocheck(iommu_mr);
iommu_idx = imrc->attrs_to_index(iommu_mr, attrs);
tcg_register_iommu_notifier(cpu, iommu_mr, iommu_idx);
/* We need all the permissions, so pass IOMMU_NONE so the IOMMU
* doesn't short-cut its translation table walk.
*/
iotlb = imrc->translate(iommu_mr, addr, IOMMU_NONE, iommu_idx);
addr = ((iotlb.translated_addr & ~iotlb.addr_mask)
| (addr & iotlb.addr_mask));
/* Update the caller's prot bits to remove permissions the IOMMU
* is giving us a failure response for. If we get down to no
* permissions left at all we can give up now.
*/
if (!(iotlb.perm & IOMMU_RO)) {
*prot &= ~(PAGE_READ | PAGE_EXEC);
}
if (!(iotlb.perm & IOMMU_WO)) {
*prot &= ~PAGE_WRITE;
}
if (!*prot) {
goto translate_fail;
}
d = flatview_to_dispatch(address_space_to_flatview(iotlb.target_as));
}
assert(!memory_region_is_iommu(section->mr));
*xlat = addr;
return section;
translate_fail:
/*
* We should be given a page-aligned address -- certainly
* tlb_set_page_with_attrs() does so. The page offset of xlat
* is used to index sections[], and PHYS_SECTION_UNASSIGNED = 0.
* The page portion of xlat will be logged by memory_region_access_valid()
* when this memory access is rejected, so use the original untranslated
* physical address.
*/
assert((orig_addr & ~TARGET_PAGE_MASK) == 0);
*xlat = orig_addr;
return &d->map.sections[PHYS_SECTION_UNASSIGNED];
}
void cpu_address_space_init(CPUState *cpu, int asidx,
const char *prefix, MemoryRegion *mr)
{
CPUAddressSpace *newas;
AddressSpace *as = g_new0(AddressSpace, 1);
char *as_name;
assert(mr);
as_name = g_strdup_printf("%s-%d", prefix, cpu->cpu_index);
address_space_init(as, mr, as_name);
g_free(as_name);
/* Target code should have set num_ases before calling us */
assert(asidx < cpu->num_ases);
if (asidx == 0) {
/* address space 0 gets the convenience alias */
cpu->as = as;
}
/* KVM cannot currently support multiple address spaces. */
assert(asidx == 0 || !kvm_enabled());
if (!cpu->cpu_ases) {
cpu->cpu_ases = g_new0(CPUAddressSpace, cpu->num_ases);
}
newas = &cpu->cpu_ases[asidx];
newas->cpu = cpu;
newas->as = as;
if (tcg_enabled()) {
newas->tcg_as_listener.log_global_after_sync = tcg_log_global_after_sync;
newas->tcg_as_listener.commit = tcg_commit;
newas->tcg_as_listener.name = "tcg";
memory_listener_register(&newas->tcg_as_listener, as);
}
}
AddressSpace *cpu_get_address_space(CPUState *cpu, int asidx)
{
/* Return the AddressSpace corresponding to the specified index */
return cpu->cpu_ases[asidx].as;
}
/* Called from RCU critical section */
static RAMBlock *qemu_get_ram_block(ram_addr_t addr)
{
RAMBlock *block;
block = qatomic_rcu_read(&ram_list.mru_block);
if (block && addr - block->offset < block->max_length) {
return block;
}
RAMBLOCK_FOREACH(block) {
if (addr - block->offset < block->max_length) {
goto found;
}
}
fprintf(stderr, "Bad ram offset %" PRIx64 "\n", (uint64_t)addr);
abort();
found:
/* It is safe to write mru_block outside the iothread lock. This
* is what happens:
*
* mru_block = xxx
* rcu_read_unlock()
* xxx removed from list
* rcu_read_lock()
* read mru_block
* mru_block = NULL;
* call_rcu(reclaim_ramblock, xxx);
* rcu_read_unlock()
*
* qatomic_rcu_set is not needed here. The block was already published
* when it was placed into the list. Here we're just making an extra
* copy of the pointer.
*/
ram_list.mru_block = block;
return block;
}
static void tlb_reset_dirty_range_all(ram_addr_t start, ram_addr_t length)
{
CPUState *cpu;
ram_addr_t start1;
RAMBlock *block;
ram_addr_t end;
assert(tcg_enabled());
end = TARGET_PAGE_ALIGN(start + length);
start &= TARGET_PAGE_MASK;
RCU_READ_LOCK_GUARD();
block = qemu_get_ram_block(start);
assert(block == qemu_get_ram_block(end - 1));
start1 = (uintptr_t)ramblock_ptr(block, start - block->offset);
CPU_FOREACH(cpu) {
tlb_reset_dirty(cpu, start1, length);
}
}
/* Note: start and end must be within the same ram block. */
bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
ram_addr_t length,
unsigned client)
{
DirtyMemoryBlocks *blocks;
unsigned long end, page, start_page;
bool dirty = false;
RAMBlock *ramblock;
uint64_t mr_offset, mr_size;
if (length == 0) {
return false;
}
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
start_page = start >> TARGET_PAGE_BITS;
page = start_page;
WITH_RCU_READ_LOCK_GUARD() {
blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
ramblock = qemu_get_ram_block(start);
/* Range sanity check on the ramblock */
assert(start >= ramblock->offset &&
start + length <= ramblock->offset + ramblock->used_length);
while (page < end) {
unsigned long idx = page / DIRTY_MEMORY_BLOCK_SIZE;
unsigned long offset = page % DIRTY_MEMORY_BLOCK_SIZE;
unsigned long num = MIN(end - page,
DIRTY_MEMORY_BLOCK_SIZE - offset);
dirty |= bitmap_test_and_clear_atomic(blocks->blocks[idx],
offset, num);
page += num;
}
mr_offset = (ram_addr_t)(start_page << TARGET_PAGE_BITS) - ramblock->offset;
mr_size = (end - start_page) << TARGET_PAGE_BITS;
memory_region_clear_dirty_bitmap(ramblock->mr, mr_offset, mr_size);
}
if (dirty && tcg_enabled()) {
tlb_reset_dirty_range_all(start, length);
}
return dirty;
}
DirtyBitmapSnapshot *cpu_physical_memory_snapshot_and_clear_dirty
(MemoryRegion *mr, hwaddr offset, hwaddr length, unsigned client)
{
DirtyMemoryBlocks *blocks;
ram_addr_t start = memory_region_get_ram_addr(mr) + offset;
unsigned long align = 1UL << (TARGET_PAGE_BITS + BITS_PER_LEVEL);
ram_addr_t first = QEMU_ALIGN_DOWN(start, align);
ram_addr_t last = QEMU_ALIGN_UP(start + length, align);
DirtyBitmapSnapshot *snap;
unsigned long page, end, dest;
snap = g_malloc0(sizeof(*snap) +
((last - first) >> (TARGET_PAGE_BITS + 3)));
snap->start = first;
snap->end = last;
page = first >> TARGET_PAGE_BITS;
end = last >> TARGET_PAGE_BITS;
dest = 0;
WITH_RCU_READ_LOCK_GUARD() {
blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
while (page < end) {
unsigned long idx = page / DIRTY_MEMORY_BLOCK_SIZE;
unsigned long offset = page % DIRTY_MEMORY_BLOCK_SIZE;
unsigned long num = MIN(end - page,
DIRTY_MEMORY_BLOCK_SIZE - offset);
assert(QEMU_IS_ALIGNED(offset, (1 << BITS_PER_LEVEL)));
assert(QEMU_IS_ALIGNED(num, (1 << BITS_PER_LEVEL)));
offset >>= BITS_PER_LEVEL;
bitmap_copy_and_clear_atomic(snap->dirty + dest,
blocks->blocks[idx] + offset,
num);
page += num;
dest += num >> BITS_PER_LEVEL;
}
}
if (tcg_enabled()) {
tlb_reset_dirty_range_all(start, length);
}
memory_region_clear_dirty_bitmap(mr, offset, length);
return snap;
}
bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
ram_addr_t start,
ram_addr_t length)
{
unsigned long page, end;
assert(start >= snap->start);
assert(start + length <= snap->end);
end = TARGET_PAGE_ALIGN(start + length - snap->start) >> TARGET_PAGE_BITS;
page = (start - snap->start) >> TARGET_PAGE_BITS;
while (page < end) {
if (test_bit(page, snap->dirty)) {
return true;
}
page++;
}
return false;
}
/* Called from RCU critical section */
hwaddr memory_region_section_get_iotlb(CPUState *cpu,
MemoryRegionSection *section)
{
AddressSpaceDispatch *d = flatview_to_dispatch(section->fv);
return section - d->map.sections;
}
static int subpage_register(subpage_t *mmio, uint32_t start, uint32_t end,
uint16_t section);
static subpage_t *subpage_init(FlatView *fv, hwaddr base);
static uint16_t phys_section_add(PhysPageMap *map,
MemoryRegionSection *section)
{
/* The physical section number is ORed with a page-aligned
* pointer to produce the iotlb entries. Thus it should
* never overflow into the page-aligned value.
*/
assert(map->sections_nb < TARGET_PAGE_SIZE);
if (map->sections_nb == map->sections_nb_alloc) {
map->sections_nb_alloc = MAX(map->sections_nb_alloc * 2, 16);
map->sections = g_renew(MemoryRegionSection, map->sections,
map->sections_nb_alloc);
}
map->sections[map->sections_nb] = *section;
memory_region_ref(section->mr);
return map->sections_nb++;
}
static void phys_section_destroy(MemoryRegion *mr)
{
bool have_sub_page = mr->subpage;
memory_region_unref(mr);
if (have_sub_page) {
subpage_t *subpage = container_of(mr, subpage_t, iomem);
object_unref(OBJECT(&subpage->iomem));
g_free(subpage);
}
}
static void phys_sections_free(PhysPageMap *map)
{
while (map->sections_nb > 0) {
MemoryRegionSection *section = &map->sections[--map->sections_nb];
phys_section_destroy(section->mr);
}
g_free(map->sections);
g_free(map->nodes);
}
static void register_subpage(FlatView *fv, MemoryRegionSection *section)
{
AddressSpaceDispatch *d = flatview_to_dispatch(fv);
subpage_t *subpage;
hwaddr base = section->offset_within_address_space
& TARGET_PAGE_MASK;
MemoryRegionSection *existing = phys_page_find(d, base);
MemoryRegionSection subsection = {
.offset_within_address_space = base,
.size = int128_make64(TARGET_PAGE_SIZE),
};
hwaddr start, end;
assert(existing->mr->subpage || existing->mr == &io_mem_unassigned);
if (!(existing->mr->subpage)) {
subpage = subpage_init(fv, base);
subsection.fv = fv;
subsection.mr = &subpage->iomem;
phys_page_set(d, base >> TARGET_PAGE_BITS, 1,
phys_section_add(&d->map, &subsection));
} else {
subpage = container_of(existing->mr, subpage_t, iomem);
}
start = section->offset_within_address_space & ~TARGET_PAGE_MASK;
end = start + int128_get64(section->size) - 1;
subpage_register(subpage, start, end,
phys_section_add(&d->map, section));
}
static void register_multipage(FlatView *fv,
MemoryRegionSection *section)
{
AddressSpaceDispatch *d = flatview_to_dispatch(fv);
hwaddr start_addr = section->offset_within_address_space;
uint16_t section_index = phys_section_add(&d->map, section);
uint64_t num_pages = int128_get64(int128_rshift(section->size,
TARGET_PAGE_BITS));
assert(num_pages);
phys_page_set(d, start_addr >> TARGET_PAGE_BITS, num_pages, section_index);
}
/*
* The range in *section* may look like this:
*
* |s|PPPPPPP|s|
*
* where s stands for subpage and P for page.
*/
void flatview_add_to_dispatch(FlatView *fv, MemoryRegionSection *section)
{
MemoryRegionSection remain = *section;
Int128 page_size = int128_make64(TARGET_PAGE_SIZE);
/* register first subpage */
if (remain.offset_within_address_space & ~TARGET_PAGE_MASK) {
uint64_t left = TARGET_PAGE_ALIGN(remain.offset_within_address_space)
- remain.offset_within_address_space;
MemoryRegionSection now = remain;
now.size = int128_min(int128_make64(left), now.size);
register_subpage(fv, &now);
if (int128_eq(remain.size, now.size)) {
return;
}
remain.size = int128_sub(remain.size, now.size);
remain.offset_within_address_space += int128_get64(now.size);
remain.offset_within_region += int128_get64(now.size);
}
/* register whole pages */
if (int128_ge(remain.size, page_size)) {
MemoryRegionSection now = remain;
now.size = int128_and(now.size, int128_neg(page_size));
register_multipage(fv, &now);
if (int128_eq(remain.size, now.size)) {
return;
}
remain.size = int128_sub(remain.size, now.size);
remain.offset_within_address_space += int128_get64(now.size);
remain.offset_within_region += int128_get64(now.size);
}
/* register last subpage */
register_subpage(fv, &remain);
}
void qemu_flush_coalesced_mmio_buffer(void)
{
if (kvm_enabled())
kvm_flush_coalesced_mmio_buffer();
}
void qemu_mutex_lock_ramlist(void)
{
qemu_mutex_lock(&ram_list.mutex);
}
void qemu_mutex_unlock_ramlist(void)
{
qemu_mutex_unlock(&ram_list.mutex);
}
GString *ram_block_format(void)
{
RAMBlock *block;
char *psize;
GString *buf = g_string_new("");
RCU_READ_LOCK_GUARD();
g_string_append_printf(buf, "%24s %8s %18s %18s %18s %18s %3s\n",
"Block Name", "PSize", "Offset", "Used", "Total",
"HVA", "RO");
RAMBLOCK_FOREACH(block) {
psize = size_to_str(block->page_size);
g_string_append_printf(buf, "%24s %8s 0x%016" PRIx64 " 0x%016" PRIx64
" 0x%016" PRIx64 " 0x%016" PRIx64 " %3s\n",
block->idstr, psize,
(uint64_t)block->offset,
(uint64_t)block->used_length,
(uint64_t)block->max_length,
(uint64_t)(uintptr_t)block->host,
block->mr->readonly ? "ro" : "rw");
g_free(psize);
}
return buf;
}
static int find_min_backend_pagesize(Object *obj, void *opaque)
{
long *hpsize_min = opaque;
if (object_dynamic_cast(obj, TYPE_MEMORY_BACKEND)) {
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
long hpsize = host_memory_backend_pagesize(backend);
if (host_memory_backend_is_mapped(backend) && (hpsize < *hpsize_min)) {
*hpsize_min = hpsize;
}
}
return 0;
}
static int find_max_backend_pagesize(Object *obj, void *opaque)
{
long *hpsize_max = opaque;
if (object_dynamic_cast(obj, TYPE_MEMORY_BACKEND)) {
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
long hpsize = host_memory_backend_pagesize(backend);
if (host_memory_backend_is_mapped(backend) && (hpsize > *hpsize_max)) {
*hpsize_max = hpsize;
}
}
return 0;
}
/*
* TODO: We assume right now that all mapped host memory backends are
* used as RAM, however some might be used for different purposes.
*/
long qemu_minrampagesize(void)
{
long hpsize = LONG_MAX;
Object *memdev_root = object_resolve_path("/objects", NULL);
object_child_foreach(memdev_root, find_min_backend_pagesize, &hpsize);
return hpsize;
}
long qemu_maxrampagesize(void)
{
long pagesize = 0;
Object *memdev_root = object_resolve_path("/objects", NULL);
object_child_foreach(memdev_root, find_max_backend_pagesize, &pagesize);
return pagesize;
}
#ifdef CONFIG_POSIX
static int64_t get_file_size(int fd)
{
int64_t size;
#if defined(__linux__)
struct stat st;
if (fstat(fd, &st) < 0) {
return -errno;
}
/* Special handling for devdax character devices */
if (S_ISCHR(st.st_mode)) {
g_autofree char *subsystem_path = NULL;
g_autofree char *subsystem = NULL;
subsystem_path = g_strdup_printf("/sys/dev/char/%d:%d/subsystem",
major(st.st_rdev), minor(st.st_rdev));
subsystem = g_file_read_link(subsystem_path, NULL);
if (subsystem && g_str_has_suffix(subsystem, "/dax")) {
g_autofree char *size_path = NULL;
g_autofree char *size_str = NULL;
size_path = g_strdup_printf("/sys/dev/char/%d:%d/size",
major(st.st_rdev), minor(st.st_rdev));
if (g_file_get_contents(size_path, &size_str, NULL, NULL)) {
return g_ascii_strtoll(size_str, NULL, 0);
}
}
}
#endif /* defined(__linux__) */
/* st.st_size may be zero for special files yet lseek(2) works */
size = lseek(fd, 0, SEEK_END);
if (size < 0) {
return -errno;
}
return size;
}
static int64_t get_file_align(int fd)
{
int64_t align = -1;
#if defined(__linux__) && defined(CONFIG_LIBDAXCTL)
struct stat st;
if (fstat(fd, &st) < 0) {
return -errno;
}
/* Special handling for devdax character devices */
if (S_ISCHR(st.st_mode)) {
g_autofree char *path = NULL;
g_autofree char *rpath = NULL;
struct daxctl_ctx *ctx;
struct daxctl_region *region;
int rc = 0;
path = g_strdup_printf("/sys/dev/char/%d:%d",
major(st.st_rdev), minor(st.st_rdev));
rpath = realpath(path, NULL);
if (!rpath) {
return -errno;
}
rc = daxctl_new(&ctx);
if (rc) {
return -1;
}
daxctl_region_foreach(ctx, region) {
if (strstr(rpath, daxctl_region_get_path(region))) {
align = daxctl_region_get_align(region);
break;
}
}
daxctl_unref(ctx);
}
#endif /* defined(__linux__) && defined(CONFIG_LIBDAXCTL) */
return align;
}
static int file_ram_open(const char *path,
const char *region_name,
bool readonly,
bool *created,
Error **errp)
{
char *filename;
char *sanitized_name;
char *c;
int fd = -1;
*created = false;
for (;;) {
fd = open(path, readonly ? O_RDONLY : O_RDWR);
if (fd >= 0) {
/* @path names an existing file, use it */
break;
}
if (errno == ENOENT) {
/* @path names a file that doesn't exist, create it */
fd = open(path, O_RDWR | O_CREAT | O_EXCL, 0644);
if (fd >= 0) {
*created = true;
break;
}
} else if (errno == EISDIR) {
/* @path names a directory, create a file there */
/* Make name safe to use with mkstemp by replacing '/' with '_'. */
sanitized_name = g_strdup(region_name);
for (c = sanitized_name; *c != '\0'; c++) {
if (*c == '/') {
*c = '_';
}
}
filename = g_strdup_printf("%s/qemu_back_mem.%s.XXXXXX", path,
sanitized_name);
g_free(sanitized_name);
fd = mkstemp(filename);
if (fd >= 0) {
unlink(filename);
g_free(filename);
break;
}
g_free(filename);
}
if (errno != EEXIST && errno != EINTR) {
error_setg_errno(errp, errno,
"can't open backing store %s for guest RAM",
path);
return -1;
}
/*
* Try again on EINTR and EEXIST. The latter happens when
* something else creates the file between our two open().
*/
}
return fd;
}
static void *file_ram_alloc(RAMBlock *block,
ram_addr_t memory,
int fd,
bool readonly,
bool truncate,
off_t offset,
Error **errp)
{
uint32_t qemu_map_flags;
void *area;
block->page_size = qemu_fd_getpagesize(fd);
if (block->mr->align % block->page_size) {
error_setg(errp, "alignment 0x%" PRIx64
" must be multiples of page size 0x%zx",
block->mr->align, block->page_size);
return NULL;
} else if (block->mr->align && !is_power_of_2(block->mr->align)) {
error_setg(errp, "alignment 0x%" PRIx64
" must be a power of two", block->mr->align);
return NULL;
}
block->mr->align = MAX(block->page_size, block->mr->align);
#if defined(__s390x__)
if (kvm_enabled()) {
block->mr->align = MAX(block->mr->align, QEMU_VMALLOC_ALIGN);
}
#endif
if (memory < block->page_size) {
error_setg(errp, "memory size 0x" RAM_ADDR_FMT " must be equal to "
"or larger than page size 0x%zx",
memory, block->page_size);
return NULL;
}
memory = ROUND_UP(memory, block->page_size);
/*
* ftruncate is not supported by hugetlbfs in older
* hosts, so don't bother bailing out on errors.
* If anything goes wrong with it under other filesystems,
* mmap will fail.
*
* Do not truncate the non-empty backend file to avoid corrupting
* the existing data in the file. Disabling shrinking is not
* enough. For example, the current vNVDIMM implementation stores
* the guest NVDIMM labels at the end of the backend file. If the
* backend file is later extended, QEMU will not be able to find
* those labels. Therefore, extending the non-empty backend file
* is disabled as well.
*/
if (truncate && ftruncate(fd, memory)) {
perror("ftruncate");
}
qemu_map_flags = readonly ? QEMU_MAP_READONLY : 0;
qemu_map_flags |= (block->flags & RAM_SHARED) ? QEMU_MAP_SHARED : 0;
qemu_map_flags |= (block->flags & RAM_PMEM) ? QEMU_MAP_SYNC : 0;
qemu_map_flags |= (block->flags & RAM_NORESERVE) ? QEMU_MAP_NORESERVE : 0;
area = qemu_ram_mmap(fd, memory, block->mr->align, qemu_map_flags, offset);
if (area == MAP_FAILED) {
error_setg_errno(errp, errno,
"unable to map backing store for guest RAM");
return NULL;
}
block->fd = fd;
return area;
}
#endif
/* Allocate space within the ram_addr_t space that governs the
* dirty bitmaps.
* Called with the ramlist lock held.
*/
static ram_addr_t find_ram_offset(ram_addr_t size)
{
RAMBlock *block, *next_block;
ram_addr_t offset = RAM_ADDR_MAX, mingap = RAM_ADDR_MAX;
assert(size != 0); /* it would hand out same offset multiple times */
if (QLIST_EMPTY_RCU(&ram_list.blocks)) {
return 0;
}
RAMBLOCK_FOREACH(block) {
ram_addr_t candidate, next = RAM_ADDR_MAX;
/* Align blocks to start on a 'long' in the bitmap
* which makes the bitmap sync'ing take the fast path.
*/
candidate = block->offset + block->max_length;
candidate = ROUND_UP(candidate, BITS_PER_LONG << TARGET_PAGE_BITS);
/* Search for the closest following block
* and find the gap.
*/
RAMBLOCK_FOREACH(next_block) {
if (next_block->offset >= candidate) {
next = MIN(next, next_block->offset);
}
}
/* If it fits remember our place and remember the size
* of gap, but keep going so that we might find a smaller
* gap to fill so avoiding fragmentation.
*/
if (next - candidate >= size && next - candidate < mingap) {
offset = candidate;
mingap = next - candidate;
}
trace_find_ram_offset_loop(size, candidate, offset, next, mingap);
}
if (offset == RAM_ADDR_MAX) {
fprintf(stderr, "Failed to find gap of requested size: %" PRIu64 "\n",
(uint64_t)size);
abort();
}
trace_find_ram_offset(size, offset);
return offset;
}
static unsigned long last_ram_page(void)
{
RAMBlock *block;
ram_addr_t last = 0;
RCU_READ_LOCK_GUARD();
RAMBLOCK_FOREACH(block) {
last = MAX(last, block->offset + block->max_length);
}
return last >> TARGET_PAGE_BITS;
}
static void qemu_ram_setup_dump(void *addr, ram_addr_t size)
{
int ret;
/* Use MADV_DONTDUMP, if user doesn't want the guest memory in the core */
if (!machine_dump_guest_core(current_machine)) {
ret = qemu_madvise(addr, size, QEMU_MADV_DONTDUMP);
if (ret) {
perror("qemu_madvise");
fprintf(stderr, "madvise doesn't support MADV_DONTDUMP, "
"but dump_guest_core=off specified\n");
}
}
}
const char *qemu_ram_get_idstr(RAMBlock *rb)
{
return rb->idstr;
}
void *qemu_ram_get_host_addr(RAMBlock *rb)
{
return rb->host;
}
ram_addr_t qemu_ram_get_offset(RAMBlock *rb)
{
return rb->offset;
}
ram_addr_t qemu_ram_get_used_length(RAMBlock *rb)
{
return rb->used_length;
}
ram_addr_t qemu_ram_get_max_length(RAMBlock *rb)
{
return rb->max_length;
}
bool qemu_ram_is_shared(RAMBlock *rb)
{
return rb->flags & RAM_SHARED;
}
bool qemu_ram_is_noreserve(RAMBlock *rb)
{
return rb->flags & RAM_NORESERVE;
}
/* Note: Only set at the start of postcopy */
bool qemu_ram_is_uf_zeroable(RAMBlock *rb)
{
return rb->flags & RAM_UF_ZEROPAGE;
}
void qemu_ram_set_uf_zeroable(RAMBlock *rb)
{
rb->flags |= RAM_UF_ZEROPAGE;
}
bool qemu_ram_is_migratable(RAMBlock *rb)
{
return rb->flags & RAM_MIGRATABLE;
}
void qemu_ram_set_migratable(RAMBlock *rb)
{
rb->flags |= RAM_MIGRATABLE;
}
void qemu_ram_unset_migratable(RAMBlock *rb)
{
rb->flags &= ~RAM_MIGRATABLE;
}
int qemu_ram_get_fd(RAMBlock *rb)
{
return rb->fd;
}
/* Called with iothread lock held. */
void qemu_ram_set_idstr(RAMBlock *new_block, const char *name, DeviceState *dev)
{
RAMBlock *block;
assert(new_block);
assert(!new_block->idstr[0]);
if (dev) {
char *id = qdev_get_dev_path(dev);
if (id) {
snprintf(new_block->idstr, sizeof(new_block->idstr), "%s/", id);
g_free(id);
}
}
pstrcat(new_block->idstr, sizeof(new_block->idstr), name);
RCU_READ_LOCK_GUARD();
RAMBLOCK_FOREACH(block) {
if (block != new_block &&
!strcmp(block->idstr, new_block->idstr)) {
fprintf(stderr, "RAMBlock \"%s\" already registered, abort!\n",
new_block->idstr);
abort();
}
}
}
/* Called with iothread lock held. */
void qemu_ram_unset_idstr(RAMBlock *block)
{
/* FIXME: arch_init.c assumes that this is not called throughout
* migration. Ignore the problem since hot-unplug during migration
* does not work anyway.
*/
if (block) {
memset(block->idstr, 0, sizeof(block->idstr));
}
}
size_t qemu_ram_pagesize(RAMBlock *rb)
{
return rb->page_size;
}
/* Returns the largest size of page in use */
size_t qemu_ram_pagesize_largest(void)
{
RAMBlock *block;
size_t largest = 0;
RAMBLOCK_FOREACH(block) {
largest = MAX(largest, qemu_ram_pagesize(block));
}
return largest;
}
static int memory_try_enable_merging(void *addr, size_t len)
{
if (!machine_mem_merge(current_machine)) {
/* disabled by the user */
return 0;
}
return qemu_madvise(addr, len, QEMU_MADV_MERGEABLE);
}
/*
* Resizing RAM while migrating can result in the migration being canceled.
* Care has to be taken if the guest might have already detected the memory.
*
* As memory core doesn't know how is memory accessed, it is up to
* resize callback to update device state and/or add assertions to detect
* misuse, if necessary.
*/
int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp)
{
const ram_addr_t oldsize = block->used_length;
const ram_addr_t unaligned_size = newsize;
assert(block);
newsize = HOST_PAGE_ALIGN(newsize);
if (block->used_length == newsize) {
/*
* We don't have to resize the ram block (which only knows aligned
* sizes), however, we have to notify if the unaligned size changed.
*/
if (unaligned_size != memory_region_size(block->mr)) {
memory_region_set_size(block->mr, unaligned_size);
if (block->resized) {
block->resized(block->idstr, unaligned_size, block->host);
}
}
return 0;
}
if (!(block->flags & RAM_RESIZEABLE)) {
error_setg_errno(errp, EINVAL,
"Size mismatch: %s: 0x" RAM_ADDR_FMT
" != 0x" RAM_ADDR_FMT, block->idstr,
newsize, block->used_length);
return -EINVAL;
}
if (block->max_length < newsize) {
error_setg_errno(errp, EINVAL,
"Size too large: %s: 0x" RAM_ADDR_FMT
" > 0x" RAM_ADDR_FMT, block->idstr,
newsize, block->max_length);
return -EINVAL;
}
/* Notify before modifying the ram block and touching the bitmaps. */
if (block->host) {
ram_block_notify_resize(block->host, oldsize, newsize);
}
cpu_physical_memory_clear_dirty_range(block->offset, block->used_length);
block->used_length = newsize;
cpu_physical_memory_set_dirty_range(block->offset, block->used_length,
DIRTY_CLIENTS_ALL);
memory_region_set_size(block->mr, unaligned_size);
if (block->resized) {
block->resized(block->idstr, unaligned_size, block->host);
}
return 0;
}
/*
* Trigger sync on the given ram block for range [start, start + length]
* with the backing store if one is available.
* Otherwise no-op.
* @Note: this is supposed to be a synchronous op.
*/
void qemu_ram_msync(RAMBlock *block, ram_addr_t start, ram_addr_t length)
{
/* The requested range should fit in within the block range */
g_assert((start + length) <= block->used_length);
#ifdef CONFIG_LIBPMEM
/* The lack of support for pmem should not block the sync */
if (ramblock_is_pmem(block)) {
void *addr = ramblock_ptr(block, start);
pmem_persist(addr, length);
return;
}
#endif
if (block->fd >= 0) {
/**
* Case there is no support for PMEM or the memory has not been
* specified as persistent (or is not one) - use the msync.
* Less optimal but still achieves the same goal
*/
void *addr = ramblock_ptr(block, start);
if (qemu_msync(addr, length, block->fd)) {
warn_report("%s: failed to sync memory range: start: "
RAM_ADDR_FMT " length: " RAM_ADDR_FMT,
__func__, start, length);
}
}
}
/* Called with ram_list.mutex held */
static void dirty_memory_extend(ram_addr_t old_ram_size,
ram_addr_t new_ram_size)
{
ram_addr_t old_num_blocks = DIV_ROUND_UP(old_ram_size,
DIRTY_MEMORY_BLOCK_SIZE);
ram_addr_t new_num_blocks = DIV_ROUND_UP(new_ram_size,
DIRTY_MEMORY_BLOCK_SIZE);
int i;
/* Only need to extend if block count increased */
if (new_num_blocks <= old_num_blocks) {
return;
}
for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
DirtyMemoryBlocks *old_blocks;
DirtyMemoryBlocks *new_blocks;
int j;
old_blocks = qatomic_rcu_read(&ram_list.dirty_memory[i]);
new_blocks = g_malloc(sizeof(*new_blocks) +
sizeof(new_blocks->blocks[0]) * new_num_blocks);
if (old_num_blocks) {
memcpy(new_blocks->blocks, old_blocks->blocks,
old_num_blocks * sizeof(old_blocks->blocks[0]));
}
for (j = old_num_blocks; j < new_num_blocks; j++) {
new_blocks->blocks[j] = bitmap_new(DIRTY_MEMORY_BLOCK_SIZE);
}
qatomic_rcu_set(&ram_list.dirty_memory[i], new_blocks);
if (old_blocks) {
g_free_rcu(old_blocks, rcu);
}
}
}
static void ram_block_add(RAMBlock *new_block, Error **errp)
{
const bool noreserve = qemu_ram_is_noreserve(new_block);
const bool shared = qemu_ram_is_shared(new_block);
RAMBlock *block;
RAMBlock *last_block = NULL;
ram_addr_t old_ram_size, new_ram_size;
Error *err = NULL;
old_ram_size = last_ram_page();
qemu_mutex_lock_ramlist();
new_block->offset = find_ram_offset(new_block->max_length);
if (!new_block->host) {
if (xen_enabled()) {
xen_ram_alloc(new_block->offset, new_block->max_length,
new_block->mr, &err);
if (err) {
error_propagate(errp, err);
qemu_mutex_unlock_ramlist();
return;
}
} else {
new_block->host = qemu_anon_ram_alloc(new_block->max_length,
&new_block->mr->align,
shared, noreserve);
if (!new_block->host) {
error_setg_errno(errp, errno,
"cannot set up guest memory '%s'",
memory_region_name(new_block->mr));
qemu_mutex_unlock_ramlist();
return;
}
memory_try_enable_merging(new_block->host, new_block->max_length);
}
}
new_ram_size = MAX(old_ram_size,
(new_block->offset + new_block->max_length) >> TARGET_PAGE_BITS);
if (new_ram_size > old_ram_size) {
dirty_memory_extend(old_ram_size, new_ram_size);
}
/* Keep the list sorted from biggest to smallest block. Unlike QTAILQ,
* QLIST (which has an RCU-friendly variant) does not have insertion at
* tail, so save the last element in last_block.
*/
RAMBLOCK_FOREACH(block) {
last_block = block;
if (block->max_length < new_block->max_length) {
break;
}
}
if (block) {
QLIST_INSERT_BEFORE_RCU(block, new_block, next);
} else if (last_block) {
QLIST_INSERT_AFTER_RCU(last_block, new_block, next);
} else { /* list is empty */
QLIST_INSERT_HEAD_RCU(&ram_list.blocks, new_block, next);
}
ram_list.mru_block = NULL;
/* Write list before version */
smp_wmb();
ram_list.version++;
qemu_mutex_unlock_ramlist();
cpu_physical_memory_set_dirty_range(new_block->offset,
new_block->used_length,
DIRTY_CLIENTS_ALL);
if (new_block->host) {
qemu_ram_setup_dump(new_block->host, new_block->max_length);
qemu_madvise(new_block->host, new_block->max_length, QEMU_MADV_HUGEPAGE);
/*
* MADV_DONTFORK is also needed by KVM in absence of synchronous MMU
* Configure it unless the machine is a qtest server, in which case
* KVM is not used and it may be forked (eg for fuzzing purposes).
*/
if (!qtest_enabled()) {
qemu_madvise(new_block->host, new_block->max_length,
QEMU_MADV_DONTFORK);
}
ram_block_notify_add(new_block->host, new_block->used_length,
new_block->max_length);
}
}
#ifdef CONFIG_POSIX
RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
uint32_t ram_flags, int fd, off_t offset,
bool readonly, Error **errp)
{
RAMBlock *new_block;
Error *local_err = NULL;
int64_t file_size, file_align;
/* Just support these ram flags by now. */
assert((ram_flags & ~(RAM_SHARED | RAM_PMEM | RAM_NORESERVE |
RAM_PROTECTED)) == 0);
if (xen_enabled()) {
error_setg(errp, "-mem-path not supported with Xen");
return NULL;
}
if (kvm_enabled() && !kvm_has_sync_mmu()) {
error_setg(errp,
"host lacks kvm mmu notifiers, -mem-path unsupported");
return NULL;
}
size = HOST_PAGE_ALIGN(size);
file_size = get_file_size(fd);
if (file_size > 0 && file_size < size) {
error_setg(errp, "backing store size 0x%" PRIx64
" does not match 'size' option 0x" RAM_ADDR_FMT,
file_size, size);
return NULL;
}
file_align = get_file_align(fd);
if (file_align > 0 && file_align > mr->align) {
error_setg(errp, "backing store align 0x%" PRIx64
" is larger than 'align' option 0x%" PRIx64,
file_align, mr->align);
return NULL;
}
new_block = g_malloc0(sizeof(*new_block));
new_block->mr = mr;
new_block->used_length = size;
new_block->max_length = size;
new_block->flags = ram_flags;
new_block->host = file_ram_alloc(new_block, size, fd, readonly,
!file_size, offset, errp);
if (!new_block->host) {
g_free(new_block);
return NULL;
}
ram_block_add(new_block, &local_err);
if (local_err) {
g_free(new_block);
error_propagate(errp, local_err);
return NULL;
}
return new_block;
}
RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
uint32_t ram_flags, const char *mem_path,
bool readonly, Error **errp)
{
int fd;
bool created;
RAMBlock *block;
fd = file_ram_open(mem_path, memory_region_name(mr), readonly, &created,
errp);
if (fd < 0) {
return NULL;
}
block = qemu_ram_alloc_from_fd(size, mr, ram_flags, fd, 0, readonly, errp);
if (!block) {
if (created) {
unlink(mem_path);
}
close(fd);
return NULL;
}
return block;
}
#endif
static
RAMBlock *qemu_ram_alloc_internal(ram_addr_t size, ram_addr_t max_size,
void (*resized)(const char*,
uint64_t length,
void *host),
void *host, uint32_t ram_flags,
MemoryRegion *mr, Error **errp)
{
RAMBlock *new_block;
Error *local_err = NULL;
assert((ram_flags & ~(RAM_SHARED | RAM_RESIZEABLE | RAM_PREALLOC |
RAM_NORESERVE)) == 0);
assert(!host ^ (ram_flags & RAM_PREALLOC));
size = HOST_PAGE_ALIGN(size);
max_size = HOST_PAGE_ALIGN(max_size);
new_block = g_malloc0(sizeof(*new_block));
new_block->mr = mr;
new_block->resized = resized;
new_block->used_length = size;
new_block->max_length = max_size;
assert(max_size >= size);
new_block->fd = -1;
new_block->page_size = qemu_real_host_page_size();
new_block->host = host;
new_block->flags = ram_flags;
ram_block_add(new_block, &local_err);
if (local_err) {
g_free(new_block);
error_propagate(errp, local_err);
return NULL;
}
return new_block;
}
RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
MemoryRegion *mr, Error **errp)
{
return qemu_ram_alloc_internal(size, size, NULL, host, RAM_PREALLOC, mr,
errp);
}
RAMBlock *qemu_ram_alloc(ram_addr_t size, uint32_t ram_flags,
MemoryRegion *mr, Error **errp)
{
assert((ram_flags & ~(RAM_SHARED | RAM_NORESERVE)) == 0);
return qemu_ram_alloc_internal(size, size, NULL, NULL, ram_flags, mr, errp);
}
RAMBlock *qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t maxsz,
void (*resized)(const char*,
uint64_t length,
void *host),
MemoryRegion *mr, Error **errp)
{
return qemu_ram_alloc_internal(size, maxsz, resized, NULL,
RAM_RESIZEABLE, mr, errp);
}
static void reclaim_ramblock(RAMBlock *block)
{
if (block->flags & RAM_PREALLOC) {
;
} else if (xen_enabled()) {
xen_invalidate_map_cache_entry(block->host);
#ifndef _WIN32
} else if (block->fd >= 0) {
qemu_ram_munmap(block->fd, block->host, block->max_length);
close(block->fd);
#endif
} else {
qemu_anon_ram_free(block->host, block->max_length);
}
g_free(block);
}
void qemu_ram_free(RAMBlock *block)
{
if (!block) {
return;
}
if (block->host) {
ram_block_notify_remove(block->host, block->used_length,
block->max_length);
}
qemu_mutex_lock_ramlist();
QLIST_REMOVE_RCU(block, next);
ram_list.mru_block = NULL;
/* Write list before version */
smp_wmb();
ram_list.version++;
call_rcu(block, reclaim_ramblock, rcu);
qemu_mutex_unlock_ramlist();
}
#ifndef _WIN32
void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)
{
RAMBlock *block;
ram_addr_t offset;
int flags;
void *area, *vaddr;
RAMBLOCK_FOREACH(block) {
offset = addr - block->offset;
if (offset < block->max_length) {
vaddr = ramblock_ptr(block, offset);
if (block->flags & RAM_PREALLOC) {
;
} else if (xen_enabled()) {
abort();
} else {
flags = MAP_FIXED;
flags |= block->flags & RAM_SHARED ?
MAP_SHARED : MAP_PRIVATE;
flags |= block->flags & RAM_NORESERVE ? MAP_NORESERVE : 0;
if (block->fd >= 0) {
area = mmap(vaddr, length, PROT_READ | PROT_WRITE,
flags, block->fd, offset);
} else {
flags |= MAP_ANONYMOUS;
area = mmap(vaddr, length, PROT_READ | PROT_WRITE,
flags, -1, 0);
}
if (area != vaddr) {
error_report("Could not remap addr: "
RAM_ADDR_FMT "@" RAM_ADDR_FMT "",
length, addr);
exit(1);
}
memory_try_enable_merging(vaddr, length);
qemu_ram_setup_dump(vaddr, length);
}
}
}
}
#endif /* !_WIN32 */
/* Return a host pointer to ram allocated with qemu_ram_alloc.
* This should not be used for general purpose DMA. Use address_space_map
* or address_space_rw instead. For local memory (e.g. video ram) that the
* device owns, use memory_region_get_ram_ptr.
*
* Called within RCU critical section.
*/
void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr)
{
RAMBlock *block = ram_block;
if (block == NULL) {
block = qemu_get_ram_block(addr);
addr -= block->offset;
}
if (xen_enabled() && block->host == NULL) {
/* We need to check if the requested address is in the RAM
* because we don't want to map the entire memory in QEMU.
* In that case just map until the end of the page.
*/
if (block->offset == 0) {
return xen_map_cache(addr, 0, 0, false);
}
block->host = xen_map_cache(block->offset, block->max_length, 1, false);
}
return ramblock_ptr(block, addr);
}
/* Return a host pointer to guest's ram. Similar to qemu_map_ram_ptr
* but takes a size argument.
*
* Called within RCU critical section.
*/
static void *qemu_ram_ptr_length(RAMBlock *ram_block, ram_addr_t addr,
hwaddr *size, bool lock)
{
RAMBlock *block = ram_block;
if (*size == 0) {
return NULL;
}
if (block == NULL) {
block = qemu_get_ram_block(addr);
addr -= block->offset;
}
*size = MIN(*size, block->max_length - addr);
if (xen_enabled() && block->host == NULL) {
/* We need to check if the requested address is in the RAM
* because we don't want to map the entire memory in QEMU.
* In that case just map the requested area.
*/
if (block->offset == 0) {
return xen_map_cache(addr, *size, lock, lock);
}
block->host = xen_map_cache(block->offset, block->max_length, 1, lock);
}
return ramblock_ptr(block, addr);
}
/* Return the offset of a hostpointer within a ramblock */
ram_addr_t qemu_ram_block_host_offset(RAMBlock *rb, void *host)
{
ram_addr_t res = (uint8_t *)host - (uint8_t *)rb->host;
assert((uintptr_t)host >= (uintptr_t)rb->host);
assert(res < rb->max_length);
return res;
}
/*
* Translates a host ptr back to a RAMBlock, a ram_addr and an offset
* in that RAMBlock.
*
* ptr: Host pointer to look up
* round_offset: If true round the result offset down to a page boundary
* *ram_addr: set to result ram_addr
* *offset: set to result offset within the RAMBlock
*
* Returns: RAMBlock (or NULL if not found)
*
* By the time this function returns, the returned pointer is not protected
* by RCU anymore. If the caller is not within an RCU critical section and
* does not hold the iothread lock, it must have other means of protecting the
* pointer, such as a reference to the region that includes the incoming
* ram_addr_t.
*/
RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset,
ram_addr_t *offset)
{
RAMBlock *block;
uint8_t *host = ptr;
if (xen_enabled()) {
ram_addr_t ram_addr;
RCU_READ_LOCK_GUARD();
ram_addr = xen_ram_addr_from_mapcache(ptr);
block = qemu_get_ram_block(ram_addr);
if (block) {
*offset = ram_addr - block->offset;
}
return block;
}
RCU_READ_LOCK_GUARD();
block = qatomic_rcu_read(&ram_list.mru_block);
if (block && block->host && host - block->host < block->max_length) {
goto found;
}
RAMBLOCK_FOREACH(block) {
/* This case append when the block is not mapped. */
if (block->host == NULL) {
continue;
}
if (host - block->host < block->max_length) {
goto found;
}
}
return NULL;
found:
*offset = (host - block->host);
if (round_offset) {
*offset &= TARGET_PAGE_MASK;
}
return block;
}
/*
* Finds the named RAMBlock
*
* name: The name of RAMBlock to find
*
* Returns: RAMBlock (or NULL if not found)
*/
RAMBlock *qemu_ram_block_by_name(const char *name)
{
RAMBlock *block;
RAMBLOCK_FOREACH(block) {
if (!strcmp(name, block->idstr)) {
return block;
}
}
return NULL;
}
/* Some of the softmmu routines need to translate from a host pointer
(typically a TLB entry) back to a ram offset. */
ram_addr_t qemu_ram_addr_from_host(void *ptr)
{
RAMBlock *block;
ram_addr_t offset;
block = qemu_ram_block_from_host(ptr, false, &offset);
if (!block) {
return RAM_ADDR_INVALID;
}
return block->offset + offset;
}
ram_addr_t qemu_ram_addr_from_host_nofail(void *ptr)
{
ram_addr_t ram_addr;
ram_addr = qemu_ram_addr_from_host(ptr);
if (ram_addr == RAM_ADDR_INVALID) {
error_report("Bad ram pointer %p", ptr);
abort();
}
return ram_addr;
}
static MemTxResult flatview_read(FlatView *fv, hwaddr addr,
MemTxAttrs attrs, void *buf, hwaddr len);
static MemTxResult flatview_write(FlatView *fv, hwaddr addr, MemTxAttrs attrs,
const void *buf, hwaddr len);
static bool flatview_access_valid(FlatView *fv, hwaddr addr, hwaddr len,
bool is_write, MemTxAttrs attrs);
static MemTxResult subpage_read(void *opaque, hwaddr addr, uint64_t *data,
unsigned len, MemTxAttrs attrs)
{
subpage_t *subpage = opaque;
uint8_t buf[8];
MemTxResult res;
#if defined(DEBUG_SUBPAGE)
printf("%s: subpage %p len %u addr " HWADDR_FMT_plx "\n", __func__,
subpage, len, addr);
#endif
res = flatview_read(subpage->fv, addr + subpage->base, attrs, buf, len);
if (res) {
return res;
}
*data = ldn_p(buf, len);
return MEMTX_OK;
}
static MemTxResult subpage_write(void *opaque, hwaddr addr,
uint64_t value, unsigned len, MemTxAttrs attrs)
{
subpage_t *subpage = opaque;
uint8_t buf[8];
#if defined(DEBUG_SUBPAGE)
printf("%s: subpage %p len %u addr " HWADDR_FMT_plx
" value %"PRIx64"\n",
__func__, subpage, len, addr, value);
#endif
stn_p(buf, len, value);
return flatview_write(subpage->fv, addr + subpage->base, attrs, buf, len);
}
static bool subpage_accepts(void *opaque, hwaddr addr,
unsigned len, bool is_write,
MemTxAttrs attrs)
{
subpage_t *subpage = opaque;
#if defined(DEBUG_SUBPAGE)
printf("%s: subpage %p %c len %u addr " HWADDR_FMT_plx "\n",
__func__, subpage, is_write ? 'w' : 'r', len, addr);
#endif
return flatview_access_valid(subpage->fv, addr + subpage->base,
len, is_write, attrs);
}
static const MemoryRegionOps subpage_ops = {
.read_with_attrs = subpage_read,
.write_with_attrs = subpage_write,
.impl.min_access_size = 1,
.impl.max_access_size = 8,
.valid.min_access_size = 1,
.valid.max_access_size = 8,
.valid.accepts = subpage_accepts,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static int subpage_register(subpage_t *mmio, uint32_t start, uint32_t end,
uint16_t section)
{
int idx, eidx;
if (start >= TARGET_PAGE_SIZE || end >= TARGET_PAGE_SIZE)
return -1;
idx = SUBPAGE_IDX(start);
eidx = SUBPAGE_IDX(end);
#if defined(DEBUG_SUBPAGE)
printf("%s: %p start %08x end %08x idx %08x eidx %08x section %d\n",
__func__, mmio, start, end, idx, eidx, section);
#endif
for (; idx <= eidx; idx++) {
mmio->sub_section[idx] = section;
}
return 0;
}
static subpage_t *subpage_init(FlatView *fv, hwaddr base)
{
subpage_t *mmio;
/* mmio->sub_section is set to PHYS_SECTION_UNASSIGNED with g_malloc0 */
mmio = g_malloc0(sizeof(subpage_t) + TARGET_PAGE_SIZE * sizeof(uint16_t));
mmio->fv = fv;
mmio->base = base;
memory_region_init_io(&mmio->iomem, NULL, &subpage_ops, mmio,
NULL, TARGET_PAGE_SIZE);
mmio->iomem.subpage = true;
#if defined(DEBUG_SUBPAGE)
printf("%s: %p base " HWADDR_FMT_plx " len %08x\n", __func__,
mmio, base, TARGET_PAGE_SIZE);
#endif
return mmio;
}
static uint16_t dummy_section(PhysPageMap *map, FlatView *fv, MemoryRegion *mr)
{
assert(fv);
MemoryRegionSection section = {
.fv = fv,
.mr = mr,
.offset_within_address_space = 0,
.offset_within_region = 0,
.size = int128_2_64(),
};
return phys_section_add(map, &section);
}
MemoryRegionSection *iotlb_to_section(CPUState *cpu,
hwaddr index, MemTxAttrs attrs)
{
int asidx = cpu_asidx_from_attrs(cpu, attrs);
CPUAddressSpace *cpuas = &cpu->cpu_ases[asidx];
AddressSpaceDispatch *d = qatomic_rcu_read(&cpuas->memory_dispatch);
MemoryRegionSection *sections = d->map.sections;
return &sections[index & ~TARGET_PAGE_MASK];
}
static void io_mem_init(void)
{
memory_region_init_io(&io_mem_unassigned, NULL, &unassigned_mem_ops, NULL,
NULL, UINT64_MAX);
}
AddressSpaceDispatch *address_space_dispatch_new(FlatView *fv)
{
AddressSpaceDispatch *d = g_new0(AddressSpaceDispatch, 1);
uint16_t n;
n = dummy_section(&d->map, fv, &io_mem_unassigned);
assert(n == PHYS_SECTION_UNASSIGNED);
d->phys_map = (PhysPageEntry) { .ptr = PHYS_MAP_NODE_NIL, .skip = 1 };
return d;
}
void address_space_dispatch_free(AddressSpaceDispatch *d)
{
phys_sections_free(&d->map);
g_free(d);
}
static void do_nothing(CPUState *cpu, run_on_cpu_data d)
{
}
static void tcg_log_global_after_sync(MemoryListener *listener)
{
CPUAddressSpace *cpuas;
/* Wait for the CPU to end the current TB. This avoids the following
* incorrect race:
*
* vCPU migration
* ---------------------- -------------------------
* TLB check -> slow path
* notdirty_mem_write
* write to RAM
* mark dirty
* clear dirty flag
* TLB check -> fast path
* read memory
* write to RAM
*
* by pushing the migration thread's memory read after the vCPU thread has
* written the memory.
*/
if (replay_mode == REPLAY_MODE_NONE) {
/*
* VGA can make calls to this function while updating the screen.
* In record/replay mode this causes a deadlock, because
* run_on_cpu waits for rr mutex. Therefore no races are possible
* in this case and no need for making run_on_cpu when
* record/replay is enabled.
*/
cpuas = container_of(listener, CPUAddressSpace, tcg_as_listener);
run_on_cpu(cpuas->cpu, do_nothing, RUN_ON_CPU_NULL);
}
}
static void tcg_commit(MemoryListener *listener)
{
CPUAddressSpace *cpuas;
AddressSpaceDispatch *d;
assert(tcg_enabled());
/* since each CPU stores ram addresses in its TLB cache, we must
reset the modified entries */
cpuas = container_of(listener, CPUAddressSpace, tcg_as_listener);
cpu_reloading_memory_map();
/* The CPU and TLB are protected by the iothread lock.
* We reload the dispatch pointer now because cpu_reloading_memory_map()
* may have split the RCU critical section.
*/
d = address_space_to_dispatch(cpuas->as);
qatomic_rcu_set(&cpuas->memory_dispatch, d);
tlb_flush(cpuas->cpu);
}
static void memory_map_init(void)
{
system_memory = g_malloc(sizeof(*system_memory));
memory_region_init(system_memory, NULL, "system", UINT64_MAX);
address_space_init(&address_space_memory, system_memory, "memory");
system_io = g_malloc(sizeof(*system_io));
memory_region_init_io(system_io, NULL, &unassigned_io_ops, NULL, "io",
65536);
address_space_init(&address_space_io, system_io, "I/O");
}
MemoryRegion *get_system_memory(void)
{
return system_memory;
}
MemoryRegion *get_system_io(void)
{
return system_io;
}
static void invalidate_and_set_dirty(MemoryRegion *mr, hwaddr addr,
hwaddr length)
{
uint8_t dirty_log_mask = memory_region_get_dirty_log_mask(mr);
addr += memory_region_get_ram_addr(mr);
/* No early return if dirty_log_mask is or becomes 0, because
* cpu_physical_memory_set_dirty_range will still call
* xen_modified_memory.
*/
if (dirty_log_mask) {
dirty_log_mask =
cpu_physical_memory_range_includes_clean(addr, length, dirty_log_mask);
}
if (dirty_log_mask & (1 << DIRTY_MEMORY_CODE)) {
assert(tcg_enabled());
tb_invalidate_phys_range(addr, addr + length - 1);
dirty_log_mask &= ~(1 << DIRTY_MEMORY_CODE);
}
cpu_physical_memory_set_dirty_range(addr, length, dirty_log_mask);
}
void memory_region_flush_rom_device(MemoryRegion *mr, hwaddr addr, hwaddr size)
{
/*
* In principle this function would work on other memory region types too,
* but the ROM device use case is the only one where this operation is
* necessary. Other memory regions should use the
* address_space_read/write() APIs.
*/
assert(memory_region_is_romd(mr));
invalidate_and_set_dirty(mr, addr, size);
}
int memory_access_size(MemoryRegion *mr, unsigned l, hwaddr addr)
{
unsigned access_size_max = mr->ops->valid.max_access_size;
/* Regions are assumed to support 1-4 byte accesses unless
otherwise specified. */
if (access_size_max == 0) {
access_size_max = 4;
}
/* Bound the maximum access by the alignment of the address. */
if (!mr->ops->impl.unaligned) {
unsigned align_size_max = addr & -addr;
if (align_size_max != 0 && align_size_max < access_size_max) {
access_size_max = align_size_max;
}
}
/* Don't attempt accesses larger than the maximum. */
if (l > access_size_max) {
l = access_size_max;
}
l = pow2floor(l);
return l;
}
bool prepare_mmio_access(MemoryRegion *mr)
{
bool release_lock = false;
if (!qemu_mutex_iothread_locked()) {
qemu_mutex_lock_iothread();
release_lock = true;
}
if (mr->flush_coalesced_mmio) {
qemu_flush_coalesced_mmio_buffer();
}
return release_lock;
}
/**
* flatview_access_allowed
* @mr: #MemoryRegion to be accessed
* @attrs: memory transaction attributes
* @addr: address within that memory region
* @len: the number of bytes to access
*
* Check if a memory transaction is allowed.
*
* Returns: true if transaction is allowed, false if denied.
*/
static bool flatview_access_allowed(MemoryRegion *mr, MemTxAttrs attrs,
hwaddr addr, hwaddr len)
{
if (likely(!attrs.memory)) {
return true;
}
if (memory_region_is_ram(mr)) {
return true;
}
qemu_log_mask(LOG_GUEST_ERROR,
"Invalid access to non-RAM device at "
"addr 0x%" HWADDR_PRIX ", size %" HWADDR_PRIu ", "
"region '%s'\n", addr, len, memory_region_name(mr));
return false;
}
/* Called within RCU critical section. */
static MemTxResult flatview_write_continue(FlatView *fv, hwaddr addr,
MemTxAttrs attrs,
const void *ptr,
hwaddr len, hwaddr addr1,
hwaddr l, MemoryRegion *mr)
{
uint8_t *ram_ptr;
uint64_t val;
MemTxResult result = MEMTX_OK;
bool release_lock = false;
const uint8_t *buf = ptr;
for (;;) {
if (!flatview_access_allowed(mr, attrs, addr1, l)) {
result |= MEMTX_ACCESS_ERROR;
/* Keep going. */
} else if (!memory_access_is_direct(mr, true)) {
release_lock |= prepare_mmio_access(mr);
l = memory_access_size(mr, l, addr1);
/* XXX: could force current_cpu to NULL to avoid
potential bugs */
val = ldn_he_p(buf, l);
result |= memory_region_dispatch_write(mr, addr1, val,
size_memop(l), attrs);
} else {
/* RAM case */
ram_ptr = qemu_ram_ptr_length(mr->ram_block, addr1, &l, false);
memmove(ram_ptr, buf, l);
invalidate_and_set_dirty(mr, addr1, l);
}
if (release_lock) {
qemu_mutex_unlock_iothread();
release_lock = false;
}
len -= l;
buf += l;
addr += l;
if (!len) {
break;
}
l = len;
mr = flatview_translate(fv, addr, &addr1, &l, true, attrs);
}
return result;
}
/* Called from RCU critical section. */
static MemTxResult flatview_write(FlatView *fv, hwaddr addr, MemTxAttrs attrs,
const void *buf, hwaddr len)
{
hwaddr l;
hwaddr addr1;
MemoryRegion *mr;
l = len;
mr = flatview_translate(fv, addr, &addr1, &l, true, attrs);
if (!flatview_access_allowed(mr, attrs, addr, len)) {
return MEMTX_ACCESS_ERROR;
}
return flatview_write_continue(fv, addr, attrs, buf, len,
addr1, l, mr);
}
/* Called within RCU critical section. */
MemTxResult flatview_read_continue(FlatView *fv, hwaddr addr,
MemTxAttrs attrs, void *ptr,
hwaddr len, hwaddr addr1, hwaddr l,
MemoryRegion *mr)
{
uint8_t *ram_ptr;
uint64_t val;
MemTxResult result = MEMTX_OK;
bool release_lock = false;
uint8_t *buf = ptr;
fuzz_dma_read_cb(addr, len, mr);
for (;;) {
if (!flatview_access_allowed(mr, attrs, addr1, l)) {
result |= MEMTX_ACCESS_ERROR;
/* Keep going. */
} else if (!memory_access_is_direct(mr, false)) {
/* I/O case */
release_lock |= prepare_mmio_access(mr);
l = memory_access_size(mr, l, addr1);
result |= memory_region_dispatch_read(mr, addr1, &val,
size_memop(l), attrs);
stn_he_p(buf, l, val);
} else {
/* RAM case */
ram_ptr = qemu_ram_ptr_length(mr->ram_block, addr1, &l, false);
memcpy(buf, ram_ptr, l);
}
if (release_lock) {
qemu_mutex_unlock_iothread();
release_lock = false;
}
len -= l;
buf += l;
addr += l;
if (!len) {
break;
}
l = len;
mr = flatview_translate(fv, addr, &addr1, &l, false, attrs);
}
return result;
}
/* Called from RCU critical section. */
static MemTxResult flatview_read(FlatView *fv, hwaddr addr,
MemTxAttrs attrs, void *buf, hwaddr len)
{
hwaddr l;
hwaddr addr1;
MemoryRegion *mr;
l = len;
mr = flatview_translate(fv, addr, &addr1, &l, false, attrs);
if (!flatview_access_allowed(mr, attrs, addr, len)) {
return MEMTX_ACCESS_ERROR;
}
return flatview_read_continue(fv, addr, attrs, buf, len,
addr1, l, mr);
}
MemTxResult address_space_read_full(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, void *buf, hwaddr len)
{
MemTxResult result = MEMTX_OK;
FlatView *fv;
if (len > 0) {
RCU_READ_LOCK_GUARD();
fv = address_space_to_flatview(as);
result = flatview_read(fv, addr, attrs, buf, len);
}
return result;
}
MemTxResult address_space_write(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs,
const void *buf, hwaddr len)
{
MemTxResult result = MEMTX_OK;
FlatView *fv;
if (len > 0) {
RCU_READ_LOCK_GUARD();
fv = address_space_to_flatview(as);
result = flatview_write(fv, addr, attrs, buf, len);
}
return result;
}
MemTxResult address_space_rw(AddressSpace *as, hwaddr addr, MemTxAttrs attrs,
void *buf, hwaddr len, bool is_write)
{
if (is_write) {
return address_space_write(as, addr, attrs, buf, len);
} else {
return address_space_read_full(as, addr, attrs, buf, len);
}
}
MemTxResult address_space_set(AddressSpace *as, hwaddr addr,
uint8_t c, hwaddr len, MemTxAttrs attrs)
{
#define FILLBUF_SIZE 512
uint8_t fillbuf[FILLBUF_SIZE];
int l;
MemTxResult error = MEMTX_OK;
memset(fillbuf, c, FILLBUF_SIZE);
while (len > 0) {
l = len < FILLBUF_SIZE ? len : FILLBUF_SIZE;
error |= address_space_write(as, addr, attrs, fillbuf, l);
len -= l;
addr += l;
}
return error;
}
void cpu_physical_memory_rw(hwaddr addr, void *buf,
hwaddr len, bool is_write)
{
address_space_rw(&address_space_memory, addr, MEMTXATTRS_UNSPECIFIED,
buf, len, is_write);
}
enum write_rom_type {
WRITE_DATA,
FLUSH_CACHE,
};
static inline MemTxResult address_space_write_rom_internal(AddressSpace *as,
hwaddr addr,
MemTxAttrs attrs,
const void *ptr,
hwaddr len,
enum write_rom_type type)
{
hwaddr l;
uint8_t *ram_ptr;
hwaddr addr1;
MemoryRegion *mr;
const uint8_t *buf = ptr;
RCU_READ_LOCK_GUARD();
while (len > 0) {
l = len;
mr = address_space_translate(as, addr, &addr1, &l, true, attrs);
if (!(memory_region_is_ram(mr) ||
memory_region_is_romd(mr))) {
l = memory_access_size(mr, l, addr1);
} else {
/* ROM/RAM case */
ram_ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
switch (type) {
case WRITE_DATA:
memcpy(ram_ptr, buf, l);
invalidate_and_set_dirty(mr, addr1, l);
break;
case FLUSH_CACHE:
flush_idcache_range((uintptr_t)ram_ptr, (uintptr_t)ram_ptr, l);
break;
}
}
len -= l;
buf += l;
addr += l;
}
return MEMTX_OK;
}
/* used for ROM loading : can write in RAM and ROM */
MemTxResult address_space_write_rom(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs,
const void *buf, hwaddr len)
{
return address_space_write_rom_internal(as, addr, attrs,
buf, len, WRITE_DATA);
}
void cpu_flush_icache_range(hwaddr start, hwaddr len)
{
/*
* This function should do the same thing as an icache flush that was
* triggered from within the guest. For TCG we are always cache coherent,
* so there is no need to flush anything. For KVM / Xen we need to flush
* the host's instruction cache at least.
*/
if (tcg_enabled()) {
return;
}
address_space_write_rom_internal(&address_space_memory,
start, MEMTXATTRS_UNSPECIFIED,
NULL, len, FLUSH_CACHE);
}
typedef struct {
MemoryRegion *mr;
void *buffer;
hwaddr addr;
hwaddr len;
bool in_use;
} BounceBuffer;
static BounceBuffer bounce;
typedef struct MapClient {
QEMUBH *bh;
QLIST_ENTRY(MapClient) link;
} MapClient;
QemuMutex map_client_list_lock;
static QLIST_HEAD(, MapClient) map_client_list
= QLIST_HEAD_INITIALIZER(map_client_list);
static void cpu_unregister_map_client_do(MapClient *client)
{
QLIST_REMOVE(client, link);
g_free(client);
}
static void cpu_notify_map_clients_locked(void)
{
MapClient *client;
while (!QLIST_EMPTY(&map_client_list)) {
client = QLIST_FIRST(&map_client_list);
qemu_bh_schedule(client->bh);
cpu_unregister_map_client_do(client);
}
}
void cpu_register_map_client(QEMUBH *bh)
{
MapClient *client = g_malloc(sizeof(*client));
qemu_mutex_lock(&map_client_list_lock);
client->bh = bh;
QLIST_INSERT_HEAD(&map_client_list, client, link);
/* Write map_client_list before reading in_use. */
smp_mb();
if (!qatomic_read(&bounce.in_use)) {
cpu_notify_map_clients_locked();
}
qemu_mutex_unlock(&map_client_list_lock);
}
void cpu_exec_init_all(void)
{
qemu_mutex_init(&ram_list.mutex);
/* The data structures we set up here depend on knowing the page size,
* so no more changes can be made after this point.
* In an ideal world, nothing we did before we had finished the
* machine setup would care about the target page size, and we could
* do this much later, rather than requiring board models to state
* up front what their requirements are.
*/
finalize_target_page_bits();
io_mem_init();
memory_map_init();
qemu_mutex_init(&map_client_list_lock);
}
void cpu_unregister_map_client(QEMUBH *bh)
{
MapClient *client;
qemu_mutex_lock(&map_client_list_lock);
QLIST_FOREACH(client, &map_client_list, link) {
if (client->bh == bh) {
cpu_unregister_map_client_do(client);
break;
}
}
qemu_mutex_unlock(&map_client_list_lock);
}
static void cpu_notify_map_clients(void)
{
qemu_mutex_lock(&map_client_list_lock);
cpu_notify_map_clients_locked();
qemu_mutex_unlock(&map_client_list_lock);
}
static bool flatview_access_valid(FlatView *fv, hwaddr addr, hwaddr len,
bool is_write, MemTxAttrs attrs)
{
MemoryRegion *mr;
hwaddr l, xlat;
while (len > 0) {
l = len;
mr = flatview_translate(fv, addr, &xlat, &l, is_write, attrs);
if (!memory_access_is_direct(mr, is_write)) {
l = memory_access_size(mr, l, addr);
if (!memory_region_access_valid(mr, xlat, l, is_write, attrs)) {
return false;
}
}
len -= l;
addr += l;
}
return true;
}
bool address_space_access_valid(AddressSpace *as, hwaddr addr,
hwaddr len, bool is_write,
MemTxAttrs attrs)
{
FlatView *fv;
RCU_READ_LOCK_GUARD();
fv = address_space_to_flatview(as);
return flatview_access_valid(fv, addr, len, is_write, attrs);
}
static hwaddr
flatview_extend_translation(FlatView *fv, hwaddr addr,
hwaddr target_len,
MemoryRegion *mr, hwaddr base, hwaddr len,
bool is_write, MemTxAttrs attrs)
{
hwaddr done = 0;
hwaddr xlat;
MemoryRegion *this_mr;
for (;;) {
target_len -= len;
addr += len;
done += len;
if (target_len == 0) {
return done;
}
len = target_len;
this_mr = flatview_translate(fv, addr, &xlat,
&len, is_write, attrs);
if (this_mr != mr || xlat != base + done) {
return done;
}
}
}
/* Map a physical memory region into a host virtual address.
* May map a subset of the requested range, given by and returned in *plen.
* May return NULL if resources needed to perform the mapping are exhausted.
* Use only for reads OR writes - not for read-modify-write operations.
* Use cpu_register_map_client() to know when retrying the map operation is
* likely to succeed.
*/
void *address_space_map(AddressSpace *as,
hwaddr addr,
hwaddr *plen,
bool is_write,
MemTxAttrs attrs)
{
hwaddr len = *plen;
hwaddr l, xlat;
MemoryRegion *mr;
FlatView *fv;
if (len == 0) {
return NULL;
}
l = len;
RCU_READ_LOCK_GUARD();
fv = address_space_to_flatview(as);
mr = flatview_translate(fv, addr, &xlat, &l, is_write, attrs);
if (!memory_access_is_direct(mr, is_write)) {
if (qatomic_xchg(&bounce.in_use, true)) {
*plen = 0;
return NULL;
}
/* Avoid unbounded allocations */
l = MIN(l, TARGET_PAGE_SIZE);
bounce.buffer = qemu_memalign(TARGET_PAGE_SIZE, l);
bounce.addr = addr;
bounce.len = l;
memory_region_ref(mr);
bounce.mr = mr;
if (!is_write) {
flatview_read(fv, addr, MEMTXATTRS_UNSPECIFIED,
bounce.buffer, l);
}
*plen = l;
return bounce.buffer;
}
memory_region_ref(mr);
*plen = flatview_extend_translation(fv, addr, len, mr, xlat,
l, is_write, attrs);
fuzz_dma_read_cb(addr, *plen, mr);
return qemu_ram_ptr_length(mr->ram_block, xlat, plen, true);
}
/* Unmaps a memory region previously mapped by address_space_map().
* Will also mark the memory as dirty if is_write is true. access_len gives
* the amount of memory that was actually read or written by the caller.
*/
void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
bool is_write, hwaddr access_len)
{
if (buffer != bounce.buffer) {
MemoryRegion *mr;
ram_addr_t addr1;
mr = memory_region_from_host(buffer, &addr1);
assert(mr != NULL);
if (is_write) {
invalidate_and_set_dirty(mr, addr1, access_len);
}
if (xen_enabled()) {
xen_invalidate_map_cache_entry(buffer);
}
memory_region_unref(mr);
return;
}
if (is_write) {
address_space_write(as, bounce.addr, MEMTXATTRS_UNSPECIFIED,
bounce.buffer, access_len);
}
qemu_vfree(bounce.buffer);
bounce.buffer = NULL;
memory_region_unref(bounce.mr);
/* Clear in_use before reading map_client_list. */
qatomic_mb_set(&bounce.in_use, false);
cpu_notify_map_clients();
}
void *cpu_physical_memory_map(hwaddr addr,
hwaddr *plen,
bool is_write)
{
return address_space_map(&address_space_memory, addr, plen, is_write,
MEMTXATTRS_UNSPECIFIED);
}
void cpu_physical_memory_unmap(void *buffer, hwaddr len,
bool is_write, hwaddr access_len)
{
return address_space_unmap(&address_space_memory, buffer, len, is_write, access_len);
}
#define ARG1_DECL AddressSpace *as
#define ARG1 as
#define SUFFIX
#define TRANSLATE(...) address_space_translate(as, __VA_ARGS__)
#define RCU_READ_LOCK(...) rcu_read_lock()
#define RCU_READ_UNLOCK(...) rcu_read_unlock()
#include "memory_ldst.c.inc"
int64_t address_space_cache_init(MemoryRegionCache *cache,
AddressSpace *as,
hwaddr addr,
hwaddr len,
bool is_write)
{
AddressSpaceDispatch *d;
hwaddr l;
MemoryRegion *mr;
Int128 diff;
assert(len > 0);
l = len;
cache->fv = address_space_get_flatview(as);
d = flatview_to_dispatch(cache->fv);
cache->mrs = *address_space_translate_internal(d, addr, &cache->xlat, &l, true);
/*
* cache->xlat is now relative to cache->mrs.mr, not to the section itself.
* Take that into account to compute how many bytes are there between
* cache->xlat and the end of the section.
*/
diff = int128_sub(cache->mrs.size,
int128_make64(cache->xlat - cache->mrs.offset_within_region));
l = int128_get64(int128_min(diff, int128_make64(l)));
mr = cache->mrs.mr;
memory_region_ref(mr);
if (memory_access_is_direct(mr, is_write)) {
/* We don't care about the memory attributes here as we're only
* doing this if we found actual RAM, which behaves the same
* regardless of attributes; so UNSPECIFIED is fine.
*/
l = flatview_extend_translation(cache->fv, addr, len, mr,
cache->xlat, l, is_write,
MEMTXATTRS_UNSPECIFIED);
cache->ptr = qemu_ram_ptr_length(mr->ram_block, cache->xlat, &l, true);
} else {
cache->ptr = NULL;
}
cache->len = l;
cache->is_write = is_write;
return l;
}
void address_space_cache_invalidate(MemoryRegionCache *cache,
hwaddr addr,
hwaddr access_len)
{
assert(cache->is_write);
if (likely(cache->ptr)) {
invalidate_and_set_dirty(cache->mrs.mr, addr + cache->xlat, access_len);
}
}
void address_space_cache_destroy(MemoryRegionCache *cache)
{
if (!cache->mrs.mr) {
return;
}
if (xen_enabled()) {
xen_invalidate_map_cache_entry(cache->ptr);
}
memory_region_unref(cache->mrs.mr);
flatview_unref(cache->fv);
cache->mrs.mr = NULL;
cache->fv = NULL;
}
/* Called from RCU critical section. This function has the same
* semantics as address_space_translate, but it only works on a
* predefined range of a MemoryRegion that was mapped with
* address_space_cache_init.
*/
static inline MemoryRegion *address_space_translate_cached(
MemoryRegionCache *cache, hwaddr addr, hwaddr *xlat,
hwaddr *plen, bool is_write, MemTxAttrs attrs)
{
MemoryRegionSection section;
MemoryRegion *mr;
IOMMUMemoryRegion *iommu_mr;
AddressSpace *target_as;
assert(!cache->ptr);
*xlat = addr + cache->xlat;
mr = cache->mrs.mr;
iommu_mr = memory_region_get_iommu(mr);
if (!iommu_mr) {
/* MMIO region. */
return mr;
}
section = address_space_translate_iommu(iommu_mr, xlat, plen,
NULL, is_write, true,
&target_as, attrs);
return section.mr;
}
/* Called from RCU critical section. address_space_read_cached uses this
* out of line function when the target is an MMIO or IOMMU region.
*/
MemTxResult
address_space_read_cached_slow(MemoryRegionCache *cache, hwaddr addr,
void *buf, hwaddr len)
{
hwaddr addr1, l;
MemoryRegion *mr;
l = len;
mr = address_space_translate_cached(cache, addr, &addr1, &l, false,
MEMTXATTRS_UNSPECIFIED);
return flatview_read_continue(cache->fv,
addr, MEMTXATTRS_UNSPECIFIED, buf, len,
addr1, l, mr);
}
/* Called from RCU critical section. address_space_write_cached uses this
* out of line function when the target is an MMIO or IOMMU region.
*/
MemTxResult
address_space_write_cached_slow(MemoryRegionCache *cache, hwaddr addr,
const void *buf, hwaddr len)
{
hwaddr addr1, l;
MemoryRegion *mr;
l = len;
mr = address_space_translate_cached(cache, addr, &addr1, &l, true,
MEMTXATTRS_UNSPECIFIED);
return flatview_write_continue(cache->fv,
addr, MEMTXATTRS_UNSPECIFIED, buf, len,
addr1, l, mr);
}
#define ARG1_DECL MemoryRegionCache *cache
#define ARG1 cache
#define SUFFIX _cached_slow
#define TRANSLATE(...) address_space_translate_cached(cache, __VA_ARGS__)
#define RCU_READ_LOCK() ((void)0)
#define RCU_READ_UNLOCK() ((void)0)
#include "memory_ldst.c.inc"
/* virtual memory access for debug (includes writing to ROM) */
int cpu_memory_rw_debug(CPUState *cpu, vaddr addr,
void *ptr, size_t len, bool is_write)
{
hwaddr phys_addr;
vaddr l, page;
uint8_t *buf = ptr;
cpu_synchronize_state(cpu);
while (len > 0) {
int asidx;
MemTxAttrs attrs;
MemTxResult res;
page = addr & TARGET_PAGE_MASK;
phys_addr = cpu_get_phys_page_attrs_debug(cpu, page, &attrs);
asidx = cpu_asidx_from_attrs(cpu, attrs);
/* if no physical page mapped, return an error */
if (phys_addr == -1)
return -1;
l = (page + TARGET_PAGE_SIZE) - addr;
if (l > len)
l = len;
phys_addr += (addr & ~TARGET_PAGE_MASK);
if (is_write) {
res = address_space_write_rom(cpu->cpu_ases[asidx].as, phys_addr,
attrs, buf, l);
} else {
res = address_space_read(cpu->cpu_ases[asidx].as, phys_addr,
attrs, buf, l);
}
if (res != MEMTX_OK) {
return -1;
}
len -= l;
buf += l;
addr += l;
}
return 0;
}
/*
* Allows code that needs to deal with migration bitmaps etc to still be built
* target independent.
*/
size_t qemu_target_page_size(void)
{
return TARGET_PAGE_SIZE;
}
int qemu_target_page_bits(void)
{
return TARGET_PAGE_BITS;
}
int qemu_target_page_bits_min(void)
{
return TARGET_PAGE_BITS_MIN;
}
/* Convert target pages to MiB (2**20). */
size_t qemu_target_pages_to_MiB(size_t pages)
{
int page_bits = TARGET_PAGE_BITS;
/* So far, the largest (non-huge) page size is 64k, i.e. 16 bits. */
g_assert(page_bits < 20);
return pages >> (20 - page_bits);
}
bool cpu_physical_memory_is_io(hwaddr phys_addr)
{
MemoryRegion*mr;
hwaddr l = 1;
RCU_READ_LOCK_GUARD();
mr = address_space_translate(&address_space_memory,
phys_addr, &phys_addr, &l, false,
MEMTXATTRS_UNSPECIFIED);
return !(memory_region_is_ram(mr) || memory_region_is_romd(mr));
}
int qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque)
{
RAMBlock *block;
int ret = 0;
RCU_READ_LOCK_GUARD();
RAMBLOCK_FOREACH(block) {
ret = func(block, opaque);
if (ret) {
break;
}
}
return ret;
}
/*
* Unmap pages of memory from start to start+length such that
* they a) read as 0, b) Trigger whatever fault mechanism
* the OS provides for postcopy.
* The pages must be unmapped by the end of the function.
* Returns: 0 on success, none-0 on failure
*
*/
int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length)
{
int ret = -1;
uint8_t *host_startaddr = rb->host + start;
if (!QEMU_PTR_IS_ALIGNED(host_startaddr, rb->page_size)) {
error_report("ram_block_discard_range: Unaligned start address: %p",
host_startaddr);
goto err;
}
if ((start + length) <= rb->max_length) {
bool need_madvise, need_fallocate;
if (!QEMU_IS_ALIGNED(length, rb->page_size)) {
error_report("ram_block_discard_range: Unaligned length: %zx",
length);
goto err;
}
errno = ENOTSUP; /* If we are missing MADVISE etc */
/* The logic here is messy;
* madvise DONTNEED fails for hugepages
* fallocate works on hugepages and shmem
* shared anonymous memory requires madvise REMOVE
*/
need_madvise = (rb->page_size == qemu_host_page_size);
need_fallocate = rb->fd != -1;
if (need_fallocate) {
/* For a file, this causes the area of the file to be zero'd
* if read, and for hugetlbfs also causes it to be unmapped
* so a userfault will trigger.
*/
#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
ret = fallocate(rb->fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
start, length);
if (ret) {
ret = -errno;
error_report("ram_block_discard_range: Failed to fallocate "
"%s:%" PRIx64 " +%zx (%d)",
rb->idstr, start, length, ret);
goto err;
}
#else
ret = -ENOSYS;
error_report("ram_block_discard_range: fallocate not available/file"
"%s:%" PRIx64 " +%zx (%d)",
rb->idstr, start, length, ret);
goto err;
#endif
}
if (need_madvise) {
/* For normal RAM this causes it to be unmapped,
* for shared memory it causes the local mapping to disappear
* and to fall back on the file contents (which we just
* fallocate'd away).
*/
#if defined(CONFIG_MADVISE)
if (qemu_ram_is_shared(rb) && rb->fd < 0) {
ret = madvise(host_startaddr, length, QEMU_MADV_REMOVE);
} else {
ret = madvise(host_startaddr, length, QEMU_MADV_DONTNEED);
}
if (ret) {
ret = -errno;
error_report("ram_block_discard_range: Failed to discard range "
"%s:%" PRIx64 " +%zx (%d)",
rb->idstr, start, length, ret);
goto err;
}
#else
ret = -ENOSYS;
error_report("ram_block_discard_range: MADVISE not available"
"%s:%" PRIx64 " +%zx (%d)",
rb->idstr, start, length, ret);
goto err;
#endif
}
trace_ram_block_discard_range(rb->idstr, host_startaddr, length,
need_madvise, need_fallocate, ret);
} else {
error_report("ram_block_discard_range: Overrun block '%s' (%" PRIu64
"/%zx/" RAM_ADDR_FMT")",
rb->idstr, start, length, rb->max_length);
}
err:
return ret;
}
bool ramblock_is_pmem(RAMBlock *rb)
{
return rb->flags & RAM_PMEM;
}
static void mtree_print_phys_entries(int start, int end, int skip, int ptr)
{
if (start == end - 1) {
qemu_printf("\t%3d ", start);
} else {
qemu_printf("\t%3d..%-3d ", start, end - 1);
}
qemu_printf(" skip=%d ", skip);
if (ptr == PHYS_MAP_NODE_NIL) {
qemu_printf(" ptr=NIL");
} else if (!skip) {
qemu_printf(" ptr=#%d", ptr);
} else {
qemu_printf(" ptr=[%d]", ptr);
}
qemu_printf("\n");
}
#define MR_SIZE(size) (int128_nz(size) ? (hwaddr)int128_get64( \
int128_sub((size), int128_one())) : 0)
void mtree_print_dispatch(AddressSpaceDispatch *d, MemoryRegion *root)
{
int i;
qemu_printf(" Dispatch\n");
qemu_printf(" Physical sections\n");
for (i = 0; i < d->map.sections_nb; ++i) {
MemoryRegionSection *s = d->map.sections + i;
const char *names[] = { " [unassigned]", " [not dirty]",
" [ROM]", " [watch]" };
qemu_printf(" #%d @" HWADDR_FMT_plx ".." HWADDR_FMT_plx
" %s%s%s%s%s",
i,
s->offset_within_address_space,
s->offset_within_address_space + MR_SIZE(s->size),
s->mr->name ? s->mr->name : "(noname)",
i < ARRAY_SIZE(names) ? names[i] : "",
s->mr == root ? " [ROOT]" : "",
s == d->mru_section ? " [MRU]" : "",
s->mr->is_iommu ? " [iommu]" : "");
if (s->mr->alias) {
qemu_printf(" alias=%s", s->mr->alias->name ?
s->mr->alias->name : "noname");
}
qemu_printf("\n");
}
qemu_printf(" Nodes (%d bits per level, %d levels) ptr=[%d] skip=%d\n",
P_L2_BITS, P_L2_LEVELS, d->phys_map.ptr, d->phys_map.skip);
for (i = 0; i < d->map.nodes_nb; ++i) {
int j, jprev;
PhysPageEntry prev;
Node *n = d->map.nodes + i;
qemu_printf(" [%d]\n", i);
for (j = 0, jprev = 0, prev = *n[0]; j < ARRAY_SIZE(*n); ++j) {
PhysPageEntry *pe = *n + j;
if (pe->ptr == prev.ptr && pe->skip == prev.skip) {
continue;
}
mtree_print_phys_entries(jprev, j, prev.skip, prev.ptr);
jprev = j;
prev = *pe;
}
if (jprev != ARRAY_SIZE(*n)) {
mtree_print_phys_entries(jprev, j, prev.skip, prev.ptr);
}
}
}
/* Require any discards to work. */
static unsigned int ram_block_discard_required_cnt;
/* Require only coordinated discards to work. */
static unsigned int ram_block_coordinated_discard_required_cnt;
/* Disable any discards. */
static unsigned int ram_block_discard_disabled_cnt;
/* Disable only uncoordinated discards. */
static unsigned int ram_block_uncoordinated_discard_disabled_cnt;
static QemuMutex ram_block_discard_disable_mutex;
static void ram_block_discard_disable_mutex_lock(void)
{
static gsize initialized;
if (g_once_init_enter(&initialized)) {
qemu_mutex_init(&ram_block_discard_disable_mutex);
g_once_init_leave(&initialized, 1);
}
qemu_mutex_lock(&ram_block_discard_disable_mutex);
}
static void ram_block_discard_disable_mutex_unlock(void)
{
qemu_mutex_unlock(&ram_block_discard_disable_mutex);
}
int ram_block_discard_disable(bool state)
{
int ret = 0;
ram_block_discard_disable_mutex_lock();
if (!state) {
ram_block_discard_disabled_cnt--;
} else if (ram_block_discard_required_cnt ||
ram_block_coordinated_discard_required_cnt) {
ret = -EBUSY;
} else {
ram_block_discard_disabled_cnt++;
}
ram_block_discard_disable_mutex_unlock();
return ret;
}
int ram_block_uncoordinated_discard_disable(bool state)
{
int ret = 0;
ram_block_discard_disable_mutex_lock();
if (!state) {
ram_block_uncoordinated_discard_disabled_cnt--;
} else if (ram_block_discard_required_cnt) {
ret = -EBUSY;
} else {
ram_block_uncoordinated_discard_disabled_cnt++;
}
ram_block_discard_disable_mutex_unlock();
return ret;
}
int ram_block_discard_require(bool state)
{
int ret = 0;
ram_block_discard_disable_mutex_lock();
if (!state) {
ram_block_discard_required_cnt--;
} else if (ram_block_discard_disabled_cnt ||
ram_block_uncoordinated_discard_disabled_cnt) {
ret = -EBUSY;
} else {
ram_block_discard_required_cnt++;
}
ram_block_discard_disable_mutex_unlock();
return ret;
}
int ram_block_coordinated_discard_require(bool state)
{
int ret = 0;
ram_block_discard_disable_mutex_lock();
if (!state) {
ram_block_coordinated_discard_required_cnt--;
} else if (ram_block_discard_disabled_cnt) {
ret = -EBUSY;
} else {
ram_block_coordinated_discard_required_cnt++;
}
ram_block_discard_disable_mutex_unlock();
return ret;
}
bool ram_block_discard_is_disabled(void)
{
return qatomic_read(&ram_block_discard_disabled_cnt) ||
qatomic_read(&ram_block_uncoordinated_discard_disabled_cnt);
}
bool ram_block_discard_is_required(void)
{
return qatomic_read(&ram_block_discard_required_cnt) ||
qatomic_read(&ram_block_coordinated_discard_required_cnt);
}