target/riscv: support for 128-bit bitwise instructions
[qemu/ar7.git] / softmmu / physmem.c
blob3524c04c2a162b717c3975cc15da300c7a033710
1 /*
2 * RAM allocation and memory access
4 * Copyright (c) 2003 Fabrice Bellard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
20 #include "qemu/osdep.h"
21 #include "qemu-common.h"
22 #include "qapi/error.h"
24 #include "qemu/cutils.h"
25 #include "qemu/cacheflush.h"
27 #ifdef CONFIG_TCG
28 #include "hw/core/tcg-cpu-ops.h"
29 #endif /* CONFIG_TCG */
31 #include "exec/exec-all.h"
32 #include "exec/target_page.h"
33 #include "hw/qdev-core.h"
34 #include "hw/qdev-properties.h"
35 #include "hw/boards.h"
36 #include "hw/xen/xen.h"
37 #include "sysemu/kvm.h"
38 #include "sysemu/tcg.h"
39 #include "sysemu/qtest.h"
40 #include "qemu/timer.h"
41 #include "qemu/config-file.h"
42 #include "qemu/error-report.h"
43 #include "qemu/qemu-print.h"
44 #include "exec/memory.h"
45 #include "exec/ioport.h"
46 #include "sysemu/dma.h"
47 #include "sysemu/hostmem.h"
48 #include "sysemu/hw_accel.h"
49 #include "sysemu/xen-mapcache.h"
50 #include "trace/trace-root.h"
52 #ifdef CONFIG_FALLOCATE_PUNCH_HOLE
53 #include <linux/falloc.h>
54 #endif
56 #include "qemu/rcu_queue.h"
57 #include "qemu/main-loop.h"
58 #include "exec/translate-all.h"
59 #include "sysemu/replay.h"
61 #include "exec/memory-internal.h"
62 #include "exec/ram_addr.h"
63 #include "exec/log.h"
65 #include "qemu/pmem.h"
67 #include "migration/vmstate.h"
69 #include "qemu/range.h"
70 #ifndef _WIN32
71 #include "qemu/mmap-alloc.h"
72 #endif
74 #include "monitor/monitor.h"
76 #ifdef CONFIG_LIBDAXCTL
77 #include <daxctl/libdaxctl.h>
78 #endif
80 //#define DEBUG_SUBPAGE
82 /* ram_list is read under rcu_read_lock()/rcu_read_unlock(). Writes
83 * are protected by the ramlist lock.
85 RAMList ram_list = { .blocks = QLIST_HEAD_INITIALIZER(ram_list.blocks) };
87 static MemoryRegion *system_memory;
88 static MemoryRegion *system_io;
90 AddressSpace address_space_io;
91 AddressSpace address_space_memory;
93 static MemoryRegion io_mem_unassigned;
95 typedef struct PhysPageEntry PhysPageEntry;
97 struct PhysPageEntry {
98 /* How many bits skip to next level (in units of L2_SIZE). 0 for a leaf. */
99 uint32_t skip : 6;
100 /* index into phys_sections (!skip) or phys_map_nodes (skip) */
101 uint32_t ptr : 26;
104 #define PHYS_MAP_NODE_NIL (((uint32_t)~0) >> 6)
106 /* Size of the L2 (and L3, etc) page tables. */
107 #define ADDR_SPACE_BITS 64
109 #define P_L2_BITS 9
110 #define P_L2_SIZE (1 << P_L2_BITS)
112 #define P_L2_LEVELS (((ADDR_SPACE_BITS - TARGET_PAGE_BITS - 1) / P_L2_BITS) + 1)
114 typedef PhysPageEntry Node[P_L2_SIZE];
116 typedef struct PhysPageMap {
117 struct rcu_head rcu;
119 unsigned sections_nb;
120 unsigned sections_nb_alloc;
121 unsigned nodes_nb;
122 unsigned nodes_nb_alloc;
123 Node *nodes;
124 MemoryRegionSection *sections;
125 } PhysPageMap;
127 struct AddressSpaceDispatch {
128 MemoryRegionSection *mru_section;
129 /* This is a multi-level map on the physical address space.
130 * The bottom level has pointers to MemoryRegionSections.
132 PhysPageEntry phys_map;
133 PhysPageMap map;
136 #define SUBPAGE_IDX(addr) ((addr) & ~TARGET_PAGE_MASK)
137 typedef struct subpage_t {
138 MemoryRegion iomem;
139 FlatView *fv;
140 hwaddr base;
141 uint16_t sub_section[];
142 } subpage_t;
144 #define PHYS_SECTION_UNASSIGNED 0
146 static void io_mem_init(void);
147 static void memory_map_init(void);
148 static void tcg_log_global_after_sync(MemoryListener *listener);
149 static void tcg_commit(MemoryListener *listener);
152 * CPUAddressSpace: all the information a CPU needs about an AddressSpace
153 * @cpu: the CPU whose AddressSpace this is
154 * @as: the AddressSpace itself
155 * @memory_dispatch: its dispatch pointer (cached, RCU protected)
156 * @tcg_as_listener: listener for tracking changes to the AddressSpace
158 struct CPUAddressSpace {
159 CPUState *cpu;
160 AddressSpace *as;
161 struct AddressSpaceDispatch *memory_dispatch;
162 MemoryListener tcg_as_listener;
165 struct DirtyBitmapSnapshot {
166 ram_addr_t start;
167 ram_addr_t end;
168 unsigned long dirty[];
171 static void phys_map_node_reserve(PhysPageMap *map, unsigned nodes)
173 static unsigned alloc_hint = 16;
174 if (map->nodes_nb + nodes > map->nodes_nb_alloc) {
175 map->nodes_nb_alloc = MAX(alloc_hint, map->nodes_nb + nodes);
176 map->nodes = g_renew(Node, map->nodes, map->nodes_nb_alloc);
177 alloc_hint = map->nodes_nb_alloc;
181 static uint32_t phys_map_node_alloc(PhysPageMap *map, bool leaf)
183 unsigned i;
184 uint32_t ret;
185 PhysPageEntry e;
186 PhysPageEntry *p;
188 ret = map->nodes_nb++;
189 p = map->nodes[ret];
190 assert(ret != PHYS_MAP_NODE_NIL);
191 assert(ret != map->nodes_nb_alloc);
193 e.skip = leaf ? 0 : 1;
194 e.ptr = leaf ? PHYS_SECTION_UNASSIGNED : PHYS_MAP_NODE_NIL;
195 for (i = 0; i < P_L2_SIZE; ++i) {
196 memcpy(&p[i], &e, sizeof(e));
198 return ret;
201 static void phys_page_set_level(PhysPageMap *map, PhysPageEntry *lp,
202 hwaddr *index, uint64_t *nb, uint16_t leaf,
203 int level)
205 PhysPageEntry *p;
206 hwaddr step = (hwaddr)1 << (level * P_L2_BITS);
208 if (lp->skip && lp->ptr == PHYS_MAP_NODE_NIL) {
209 lp->ptr = phys_map_node_alloc(map, level == 0);
211 p = map->nodes[lp->ptr];
212 lp = &p[(*index >> (level * P_L2_BITS)) & (P_L2_SIZE - 1)];
214 while (*nb && lp < &p[P_L2_SIZE]) {
215 if ((*index & (step - 1)) == 0 && *nb >= step) {
216 lp->skip = 0;
217 lp->ptr = leaf;
218 *index += step;
219 *nb -= step;
220 } else {
221 phys_page_set_level(map, lp, index, nb, leaf, level - 1);
223 ++lp;
227 static void phys_page_set(AddressSpaceDispatch *d,
228 hwaddr index, uint64_t nb,
229 uint16_t leaf)
231 /* Wildly overreserve - it doesn't matter much. */
232 phys_map_node_reserve(&d->map, 3 * P_L2_LEVELS);
234 phys_page_set_level(&d->map, &d->phys_map, &index, &nb, leaf, P_L2_LEVELS - 1);
237 /* Compact a non leaf page entry. Simply detect that the entry has a single child,
238 * and update our entry so we can skip it and go directly to the destination.
240 static void phys_page_compact(PhysPageEntry *lp, Node *nodes)
242 unsigned valid_ptr = P_L2_SIZE;
243 int valid = 0;
244 PhysPageEntry *p;
245 int i;
247 if (lp->ptr == PHYS_MAP_NODE_NIL) {
248 return;
251 p = nodes[lp->ptr];
252 for (i = 0; i < P_L2_SIZE; i++) {
253 if (p[i].ptr == PHYS_MAP_NODE_NIL) {
254 continue;
257 valid_ptr = i;
258 valid++;
259 if (p[i].skip) {
260 phys_page_compact(&p[i], nodes);
264 /* We can only compress if there's only one child. */
265 if (valid != 1) {
266 return;
269 assert(valid_ptr < P_L2_SIZE);
271 /* Don't compress if it won't fit in the # of bits we have. */
272 if (P_L2_LEVELS >= (1 << 6) &&
273 lp->skip + p[valid_ptr].skip >= (1 << 6)) {
274 return;
277 lp->ptr = p[valid_ptr].ptr;
278 if (!p[valid_ptr].skip) {
279 /* If our only child is a leaf, make this a leaf. */
280 /* By design, we should have made this node a leaf to begin with so we
281 * should never reach here.
282 * But since it's so simple to handle this, let's do it just in case we
283 * change this rule.
285 lp->skip = 0;
286 } else {
287 lp->skip += p[valid_ptr].skip;
291 void address_space_dispatch_compact(AddressSpaceDispatch *d)
293 if (d->phys_map.skip) {
294 phys_page_compact(&d->phys_map, d->map.nodes);
298 static inline bool section_covers_addr(const MemoryRegionSection *section,
299 hwaddr addr)
301 /* Memory topology clips a memory region to [0, 2^64); size.hi > 0 means
302 * the section must cover the entire address space.
304 return int128_gethi(section->size) ||
305 range_covers_byte(section->offset_within_address_space,
306 int128_getlo(section->size), addr);
309 static MemoryRegionSection *phys_page_find(AddressSpaceDispatch *d, hwaddr addr)
311 PhysPageEntry lp = d->phys_map, *p;
312 Node *nodes = d->map.nodes;
313 MemoryRegionSection *sections = d->map.sections;
314 hwaddr index = addr >> TARGET_PAGE_BITS;
315 int i;
317 for (i = P_L2_LEVELS; lp.skip && (i -= lp.skip) >= 0;) {
318 if (lp.ptr == PHYS_MAP_NODE_NIL) {
319 return &sections[PHYS_SECTION_UNASSIGNED];
321 p = nodes[lp.ptr];
322 lp = p[(index >> (i * P_L2_BITS)) & (P_L2_SIZE - 1)];
325 if (section_covers_addr(&sections[lp.ptr], addr)) {
326 return &sections[lp.ptr];
327 } else {
328 return &sections[PHYS_SECTION_UNASSIGNED];
332 /* Called from RCU critical section */
333 static MemoryRegionSection *address_space_lookup_region(AddressSpaceDispatch *d,
334 hwaddr addr,
335 bool resolve_subpage)
337 MemoryRegionSection *section = qatomic_read(&d->mru_section);
338 subpage_t *subpage;
340 if (!section || section == &d->map.sections[PHYS_SECTION_UNASSIGNED] ||
341 !section_covers_addr(section, addr)) {
342 section = phys_page_find(d, addr);
343 qatomic_set(&d->mru_section, section);
345 if (resolve_subpage && section->mr->subpage) {
346 subpage = container_of(section->mr, subpage_t, iomem);
347 section = &d->map.sections[subpage->sub_section[SUBPAGE_IDX(addr)]];
349 return section;
352 /* Called from RCU critical section */
353 static MemoryRegionSection *
354 address_space_translate_internal(AddressSpaceDispatch *d, hwaddr addr, hwaddr *xlat,
355 hwaddr *plen, bool resolve_subpage)
357 MemoryRegionSection *section;
358 MemoryRegion *mr;
359 Int128 diff;
361 section = address_space_lookup_region(d, addr, resolve_subpage);
362 /* Compute offset within MemoryRegionSection */
363 addr -= section->offset_within_address_space;
365 /* Compute offset within MemoryRegion */
366 *xlat = addr + section->offset_within_region;
368 mr = section->mr;
370 /* MMIO registers can be expected to perform full-width accesses based only
371 * on their address, without considering adjacent registers that could
372 * decode to completely different MemoryRegions. When such registers
373 * exist (e.g. I/O ports 0xcf8 and 0xcf9 on most PC chipsets), MMIO
374 * regions overlap wildly. For this reason we cannot clamp the accesses
375 * here.
377 * If the length is small (as is the case for address_space_ldl/stl),
378 * everything works fine. If the incoming length is large, however,
379 * the caller really has to do the clamping through memory_access_size.
381 if (memory_region_is_ram(mr)) {
382 diff = int128_sub(section->size, int128_make64(addr));
383 *plen = int128_get64(int128_min(diff, int128_make64(*plen)));
385 return section;
389 * address_space_translate_iommu - translate an address through an IOMMU
390 * memory region and then through the target address space.
392 * @iommu_mr: the IOMMU memory region that we start the translation from
393 * @addr: the address to be translated through the MMU
394 * @xlat: the translated address offset within the destination memory region.
395 * It cannot be %NULL.
396 * @plen_out: valid read/write length of the translated address. It
397 * cannot be %NULL.
398 * @page_mask_out: page mask for the translated address. This
399 * should only be meaningful for IOMMU translated
400 * addresses, since there may be huge pages that this bit
401 * would tell. It can be %NULL if we don't care about it.
402 * @is_write: whether the translation operation is for write
403 * @is_mmio: whether this can be MMIO, set true if it can
404 * @target_as: the address space targeted by the IOMMU
405 * @attrs: transaction attributes
407 * This function is called from RCU critical section. It is the common
408 * part of flatview_do_translate and address_space_translate_cached.
410 static MemoryRegionSection address_space_translate_iommu(IOMMUMemoryRegion *iommu_mr,
411 hwaddr *xlat,
412 hwaddr *plen_out,
413 hwaddr *page_mask_out,
414 bool is_write,
415 bool is_mmio,
416 AddressSpace **target_as,
417 MemTxAttrs attrs)
419 MemoryRegionSection *section;
420 hwaddr page_mask = (hwaddr)-1;
422 do {
423 hwaddr addr = *xlat;
424 IOMMUMemoryRegionClass *imrc = memory_region_get_iommu_class_nocheck(iommu_mr);
425 int iommu_idx = 0;
426 IOMMUTLBEntry iotlb;
428 if (imrc->attrs_to_index) {
429 iommu_idx = imrc->attrs_to_index(iommu_mr, attrs);
432 iotlb = imrc->translate(iommu_mr, addr, is_write ?
433 IOMMU_WO : IOMMU_RO, iommu_idx);
435 if (!(iotlb.perm & (1 << is_write))) {
436 goto unassigned;
439 addr = ((iotlb.translated_addr & ~iotlb.addr_mask)
440 | (addr & iotlb.addr_mask));
441 page_mask &= iotlb.addr_mask;
442 *plen_out = MIN(*plen_out, (addr | iotlb.addr_mask) - addr + 1);
443 *target_as = iotlb.target_as;
445 section = address_space_translate_internal(
446 address_space_to_dispatch(iotlb.target_as), addr, xlat,
447 plen_out, is_mmio);
449 iommu_mr = memory_region_get_iommu(section->mr);
450 } while (unlikely(iommu_mr));
452 if (page_mask_out) {
453 *page_mask_out = page_mask;
455 return *section;
457 unassigned:
458 return (MemoryRegionSection) { .mr = &io_mem_unassigned };
462 * flatview_do_translate - translate an address in FlatView
464 * @fv: the flat view that we want to translate on
465 * @addr: the address to be translated in above address space
466 * @xlat: the translated address offset within memory region. It
467 * cannot be @NULL.
468 * @plen_out: valid read/write length of the translated address. It
469 * can be @NULL when we don't care about it.
470 * @page_mask_out: page mask for the translated address. This
471 * should only be meaningful for IOMMU translated
472 * addresses, since there may be huge pages that this bit
473 * would tell. It can be @NULL if we don't care about it.
474 * @is_write: whether the translation operation is for write
475 * @is_mmio: whether this can be MMIO, set true if it can
476 * @target_as: the address space targeted by the IOMMU
477 * @attrs: memory transaction attributes
479 * This function is called from RCU critical section
481 static MemoryRegionSection flatview_do_translate(FlatView *fv,
482 hwaddr addr,
483 hwaddr *xlat,
484 hwaddr *plen_out,
485 hwaddr *page_mask_out,
486 bool is_write,
487 bool is_mmio,
488 AddressSpace **target_as,
489 MemTxAttrs attrs)
491 MemoryRegionSection *section;
492 IOMMUMemoryRegion *iommu_mr;
493 hwaddr plen = (hwaddr)(-1);
495 if (!plen_out) {
496 plen_out = &plen;
499 section = address_space_translate_internal(
500 flatview_to_dispatch(fv), addr, xlat,
501 plen_out, is_mmio);
503 iommu_mr = memory_region_get_iommu(section->mr);
504 if (unlikely(iommu_mr)) {
505 return address_space_translate_iommu(iommu_mr, xlat,
506 plen_out, page_mask_out,
507 is_write, is_mmio,
508 target_as, attrs);
510 if (page_mask_out) {
511 /* Not behind an IOMMU, use default page size. */
512 *page_mask_out = ~TARGET_PAGE_MASK;
515 return *section;
518 /* Called from RCU critical section */
519 IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
520 bool is_write, MemTxAttrs attrs)
522 MemoryRegionSection section;
523 hwaddr xlat, page_mask;
526 * This can never be MMIO, and we don't really care about plen,
527 * but page mask.
529 section = flatview_do_translate(address_space_to_flatview(as), addr, &xlat,
530 NULL, &page_mask, is_write, false, &as,
531 attrs);
533 /* Illegal translation */
534 if (section.mr == &io_mem_unassigned) {
535 goto iotlb_fail;
538 /* Convert memory region offset into address space offset */
539 xlat += section.offset_within_address_space -
540 section.offset_within_region;
542 return (IOMMUTLBEntry) {
543 .target_as = as,
544 .iova = addr & ~page_mask,
545 .translated_addr = xlat & ~page_mask,
546 .addr_mask = page_mask,
547 /* IOTLBs are for DMAs, and DMA only allows on RAMs. */
548 .perm = IOMMU_RW,
551 iotlb_fail:
552 return (IOMMUTLBEntry) {0};
555 /* Called from RCU critical section */
556 MemoryRegion *flatview_translate(FlatView *fv, hwaddr addr, hwaddr *xlat,
557 hwaddr *plen, bool is_write,
558 MemTxAttrs attrs)
560 MemoryRegion *mr;
561 MemoryRegionSection section;
562 AddressSpace *as = NULL;
564 /* This can be MMIO, so setup MMIO bit. */
565 section = flatview_do_translate(fv, addr, xlat, plen, NULL,
566 is_write, true, &as, attrs);
567 mr = section.mr;
569 if (xen_enabled() && memory_access_is_direct(mr, is_write)) {
570 hwaddr page = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - addr;
571 *plen = MIN(page, *plen);
574 return mr;
577 typedef struct TCGIOMMUNotifier {
578 IOMMUNotifier n;
579 MemoryRegion *mr;
580 CPUState *cpu;
581 int iommu_idx;
582 bool active;
583 } TCGIOMMUNotifier;
585 static void tcg_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
587 TCGIOMMUNotifier *notifier = container_of(n, TCGIOMMUNotifier, n);
589 if (!notifier->active) {
590 return;
592 tlb_flush(notifier->cpu);
593 notifier->active = false;
594 /* We leave the notifier struct on the list to avoid reallocating it later.
595 * Generally the number of IOMMUs a CPU deals with will be small.
596 * In any case we can't unregister the iommu notifier from a notify
597 * callback.
601 static void tcg_register_iommu_notifier(CPUState *cpu,
602 IOMMUMemoryRegion *iommu_mr,
603 int iommu_idx)
605 /* Make sure this CPU has an IOMMU notifier registered for this
606 * IOMMU/IOMMU index combination, so that we can flush its TLB
607 * when the IOMMU tells us the mappings we've cached have changed.
609 MemoryRegion *mr = MEMORY_REGION(iommu_mr);
610 TCGIOMMUNotifier *notifier = NULL;
611 int i;
613 for (i = 0; i < cpu->iommu_notifiers->len; i++) {
614 notifier = g_array_index(cpu->iommu_notifiers, TCGIOMMUNotifier *, i);
615 if (notifier->mr == mr && notifier->iommu_idx == iommu_idx) {
616 break;
619 if (i == cpu->iommu_notifiers->len) {
620 /* Not found, add a new entry at the end of the array */
621 cpu->iommu_notifiers = g_array_set_size(cpu->iommu_notifiers, i + 1);
622 notifier = g_new0(TCGIOMMUNotifier, 1);
623 g_array_index(cpu->iommu_notifiers, TCGIOMMUNotifier *, i) = notifier;
625 notifier->mr = mr;
626 notifier->iommu_idx = iommu_idx;
627 notifier->cpu = cpu;
628 /* Rather than trying to register interest in the specific part
629 * of the iommu's address space that we've accessed and then
630 * expand it later as subsequent accesses touch more of it, we
631 * just register interest in the whole thing, on the assumption
632 * that iommu reconfiguration will be rare.
634 iommu_notifier_init(&notifier->n,
635 tcg_iommu_unmap_notify,
636 IOMMU_NOTIFIER_UNMAP,
638 HWADDR_MAX,
639 iommu_idx);
640 memory_region_register_iommu_notifier(notifier->mr, &notifier->n,
641 &error_fatal);
644 if (!notifier->active) {
645 notifier->active = true;
649 void tcg_iommu_free_notifier_list(CPUState *cpu)
651 /* Destroy the CPU's notifier list */
652 int i;
653 TCGIOMMUNotifier *notifier;
655 for (i = 0; i < cpu->iommu_notifiers->len; i++) {
656 notifier = g_array_index(cpu->iommu_notifiers, TCGIOMMUNotifier *, i);
657 memory_region_unregister_iommu_notifier(notifier->mr, &notifier->n);
658 g_free(notifier);
660 g_array_free(cpu->iommu_notifiers, true);
663 void tcg_iommu_init_notifier_list(CPUState *cpu)
665 cpu->iommu_notifiers = g_array_new(false, true, sizeof(TCGIOMMUNotifier *));
668 /* Called from RCU critical section */
669 MemoryRegionSection *
670 address_space_translate_for_iotlb(CPUState *cpu, int asidx, hwaddr addr,
671 hwaddr *xlat, hwaddr *plen,
672 MemTxAttrs attrs, int *prot)
674 MemoryRegionSection *section;
675 IOMMUMemoryRegion *iommu_mr;
676 IOMMUMemoryRegionClass *imrc;
677 IOMMUTLBEntry iotlb;
678 int iommu_idx;
679 AddressSpaceDispatch *d =
680 qatomic_rcu_read(&cpu->cpu_ases[asidx].memory_dispatch);
682 for (;;) {
683 section = address_space_translate_internal(d, addr, &addr, plen, false);
685 iommu_mr = memory_region_get_iommu(section->mr);
686 if (!iommu_mr) {
687 break;
690 imrc = memory_region_get_iommu_class_nocheck(iommu_mr);
692 iommu_idx = imrc->attrs_to_index(iommu_mr, attrs);
693 tcg_register_iommu_notifier(cpu, iommu_mr, iommu_idx);
694 /* We need all the permissions, so pass IOMMU_NONE so the IOMMU
695 * doesn't short-cut its translation table walk.
697 iotlb = imrc->translate(iommu_mr, addr, IOMMU_NONE, iommu_idx);
698 addr = ((iotlb.translated_addr & ~iotlb.addr_mask)
699 | (addr & iotlb.addr_mask));
700 /* Update the caller's prot bits to remove permissions the IOMMU
701 * is giving us a failure response for. If we get down to no
702 * permissions left at all we can give up now.
704 if (!(iotlb.perm & IOMMU_RO)) {
705 *prot &= ~(PAGE_READ | PAGE_EXEC);
707 if (!(iotlb.perm & IOMMU_WO)) {
708 *prot &= ~PAGE_WRITE;
711 if (!*prot) {
712 goto translate_fail;
715 d = flatview_to_dispatch(address_space_to_flatview(iotlb.target_as));
718 assert(!memory_region_is_iommu(section->mr));
719 *xlat = addr;
720 return section;
722 translate_fail:
723 return &d->map.sections[PHYS_SECTION_UNASSIGNED];
726 void cpu_address_space_init(CPUState *cpu, int asidx,
727 const char *prefix, MemoryRegion *mr)
729 CPUAddressSpace *newas;
730 AddressSpace *as = g_new0(AddressSpace, 1);
731 char *as_name;
733 assert(mr);
734 as_name = g_strdup_printf("%s-%d", prefix, cpu->cpu_index);
735 address_space_init(as, mr, as_name);
736 g_free(as_name);
738 /* Target code should have set num_ases before calling us */
739 assert(asidx < cpu->num_ases);
741 if (asidx == 0) {
742 /* address space 0 gets the convenience alias */
743 cpu->as = as;
746 /* KVM cannot currently support multiple address spaces. */
747 assert(asidx == 0 || !kvm_enabled());
749 if (!cpu->cpu_ases) {
750 cpu->cpu_ases = g_new0(CPUAddressSpace, cpu->num_ases);
753 newas = &cpu->cpu_ases[asidx];
754 newas->cpu = cpu;
755 newas->as = as;
756 if (tcg_enabled()) {
757 newas->tcg_as_listener.log_global_after_sync = tcg_log_global_after_sync;
758 newas->tcg_as_listener.commit = tcg_commit;
759 newas->tcg_as_listener.name = "tcg";
760 memory_listener_register(&newas->tcg_as_listener, as);
764 AddressSpace *cpu_get_address_space(CPUState *cpu, int asidx)
766 /* Return the AddressSpace corresponding to the specified index */
767 return cpu->cpu_ases[asidx].as;
770 /* Add a watchpoint. */
771 int cpu_watchpoint_insert(CPUState *cpu, vaddr addr, vaddr len,
772 int flags, CPUWatchpoint **watchpoint)
774 CPUWatchpoint *wp;
775 vaddr in_page;
777 /* forbid ranges which are empty or run off the end of the address space */
778 if (len == 0 || (addr + len - 1) < addr) {
779 error_report("tried to set invalid watchpoint at %"
780 VADDR_PRIx ", len=%" VADDR_PRIu, addr, len);
781 return -EINVAL;
783 wp = g_malloc(sizeof(*wp));
785 wp->vaddr = addr;
786 wp->len = len;
787 wp->flags = flags;
789 /* keep all GDB-injected watchpoints in front */
790 if (flags & BP_GDB) {
791 QTAILQ_INSERT_HEAD(&cpu->watchpoints, wp, entry);
792 } else {
793 QTAILQ_INSERT_TAIL(&cpu->watchpoints, wp, entry);
796 in_page = -(addr | TARGET_PAGE_MASK);
797 if (len <= in_page) {
798 tlb_flush_page(cpu, addr);
799 } else {
800 tlb_flush(cpu);
803 if (watchpoint)
804 *watchpoint = wp;
805 return 0;
808 /* Remove a specific watchpoint. */
809 int cpu_watchpoint_remove(CPUState *cpu, vaddr addr, vaddr len,
810 int flags)
812 CPUWatchpoint *wp;
814 QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
815 if (addr == wp->vaddr && len == wp->len
816 && flags == (wp->flags & ~BP_WATCHPOINT_HIT)) {
817 cpu_watchpoint_remove_by_ref(cpu, wp);
818 return 0;
821 return -ENOENT;
824 /* Remove a specific watchpoint by reference. */
825 void cpu_watchpoint_remove_by_ref(CPUState *cpu, CPUWatchpoint *watchpoint)
827 QTAILQ_REMOVE(&cpu->watchpoints, watchpoint, entry);
829 tlb_flush_page(cpu, watchpoint->vaddr);
831 g_free(watchpoint);
834 /* Remove all matching watchpoints. */
835 void cpu_watchpoint_remove_all(CPUState *cpu, int mask)
837 CPUWatchpoint *wp, *next;
839 QTAILQ_FOREACH_SAFE(wp, &cpu->watchpoints, entry, next) {
840 if (wp->flags & mask) {
841 cpu_watchpoint_remove_by_ref(cpu, wp);
846 #ifdef CONFIG_TCG
847 /* Return true if this watchpoint address matches the specified
848 * access (ie the address range covered by the watchpoint overlaps
849 * partially or completely with the address range covered by the
850 * access).
852 static inline bool watchpoint_address_matches(CPUWatchpoint *wp,
853 vaddr addr, vaddr len)
855 /* We know the lengths are non-zero, but a little caution is
856 * required to avoid errors in the case where the range ends
857 * exactly at the top of the address space and so addr + len
858 * wraps round to zero.
860 vaddr wpend = wp->vaddr + wp->len - 1;
861 vaddr addrend = addr + len - 1;
863 return !(addr > wpend || wp->vaddr > addrend);
866 /* Return flags for watchpoints that match addr + prot. */
867 int cpu_watchpoint_address_matches(CPUState *cpu, vaddr addr, vaddr len)
869 CPUWatchpoint *wp;
870 int ret = 0;
872 QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
873 if (watchpoint_address_matches(wp, addr, len)) {
874 ret |= wp->flags;
877 return ret;
880 /* Generate a debug exception if a watchpoint has been hit. */
881 void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len,
882 MemTxAttrs attrs, int flags, uintptr_t ra)
884 CPUClass *cc = CPU_GET_CLASS(cpu);
885 CPUWatchpoint *wp;
887 assert(tcg_enabled());
888 if (cpu->watchpoint_hit) {
890 * We re-entered the check after replacing the TB.
891 * Now raise the debug interrupt so that it will
892 * trigger after the current instruction.
894 qemu_mutex_lock_iothread();
895 cpu_interrupt(cpu, CPU_INTERRUPT_DEBUG);
896 qemu_mutex_unlock_iothread();
897 return;
900 if (cc->tcg_ops->adjust_watchpoint_address) {
901 /* this is currently used only by ARM BE32 */
902 addr = cc->tcg_ops->adjust_watchpoint_address(cpu, addr, len);
904 QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
905 if (watchpoint_address_matches(wp, addr, len)
906 && (wp->flags & flags)) {
907 if (replay_running_debug()) {
909 * replay_breakpoint reads icount.
910 * Force recompile to succeed, because icount may
911 * be read only at the end of the block.
913 if (!cpu->can_do_io) {
914 /* Force execution of one insn next time. */
915 cpu->cflags_next_tb = 1 | CF_LAST_IO | CF_NOIRQ | curr_cflags(cpu);
916 cpu_loop_exit_restore(cpu, ra);
919 * Don't process the watchpoints when we are
920 * in a reverse debugging operation.
922 replay_breakpoint();
923 return;
925 if (flags == BP_MEM_READ) {
926 wp->flags |= BP_WATCHPOINT_HIT_READ;
927 } else {
928 wp->flags |= BP_WATCHPOINT_HIT_WRITE;
930 wp->hitaddr = MAX(addr, wp->vaddr);
931 wp->hitattrs = attrs;
933 if (wp->flags & BP_CPU && cc->tcg_ops->debug_check_watchpoint &&
934 !cc->tcg_ops->debug_check_watchpoint(cpu, wp)) {
935 wp->flags &= ~BP_WATCHPOINT_HIT;
936 continue;
938 cpu->watchpoint_hit = wp;
940 mmap_lock();
941 /* This call also restores vCPU state */
942 tb_check_watchpoint(cpu, ra);
943 if (wp->flags & BP_STOP_BEFORE_ACCESS) {
944 cpu->exception_index = EXCP_DEBUG;
945 mmap_unlock();
946 cpu_loop_exit(cpu);
947 } else {
948 /* Force execution of one insn next time. */
949 cpu->cflags_next_tb = 1 | CF_LAST_IO | CF_NOIRQ | curr_cflags(cpu);
950 mmap_unlock();
951 cpu_loop_exit_noexc(cpu);
953 } else {
954 wp->flags &= ~BP_WATCHPOINT_HIT;
959 #endif /* CONFIG_TCG */
961 /* Called from RCU critical section */
962 static RAMBlock *qemu_get_ram_block(ram_addr_t addr)
964 RAMBlock *block;
966 block = qatomic_rcu_read(&ram_list.mru_block);
967 if (block && addr - block->offset < block->max_length) {
968 return block;
970 RAMBLOCK_FOREACH(block) {
971 if (addr - block->offset < block->max_length) {
972 goto found;
976 fprintf(stderr, "Bad ram offset %" PRIx64 "\n", (uint64_t)addr);
977 abort();
979 found:
980 /* It is safe to write mru_block outside the iothread lock. This
981 * is what happens:
983 * mru_block = xxx
984 * rcu_read_unlock()
985 * xxx removed from list
986 * rcu_read_lock()
987 * read mru_block
988 * mru_block = NULL;
989 * call_rcu(reclaim_ramblock, xxx);
990 * rcu_read_unlock()
992 * qatomic_rcu_set is not needed here. The block was already published
993 * when it was placed into the list. Here we're just making an extra
994 * copy of the pointer.
996 ram_list.mru_block = block;
997 return block;
1000 static void tlb_reset_dirty_range_all(ram_addr_t start, ram_addr_t length)
1002 CPUState *cpu;
1003 ram_addr_t start1;
1004 RAMBlock *block;
1005 ram_addr_t end;
1007 assert(tcg_enabled());
1008 end = TARGET_PAGE_ALIGN(start + length);
1009 start &= TARGET_PAGE_MASK;
1011 RCU_READ_LOCK_GUARD();
1012 block = qemu_get_ram_block(start);
1013 assert(block == qemu_get_ram_block(end - 1));
1014 start1 = (uintptr_t)ramblock_ptr(block, start - block->offset);
1015 CPU_FOREACH(cpu) {
1016 tlb_reset_dirty(cpu, start1, length);
1020 /* Note: start and end must be within the same ram block. */
1021 bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
1022 ram_addr_t length,
1023 unsigned client)
1025 DirtyMemoryBlocks *blocks;
1026 unsigned long end, page, start_page;
1027 bool dirty = false;
1028 RAMBlock *ramblock;
1029 uint64_t mr_offset, mr_size;
1031 if (length == 0) {
1032 return false;
1035 end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
1036 start_page = start >> TARGET_PAGE_BITS;
1037 page = start_page;
1039 WITH_RCU_READ_LOCK_GUARD() {
1040 blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
1041 ramblock = qemu_get_ram_block(start);
1042 /* Range sanity check on the ramblock */
1043 assert(start >= ramblock->offset &&
1044 start + length <= ramblock->offset + ramblock->used_length);
1046 while (page < end) {
1047 unsigned long idx = page / DIRTY_MEMORY_BLOCK_SIZE;
1048 unsigned long offset = page % DIRTY_MEMORY_BLOCK_SIZE;
1049 unsigned long num = MIN(end - page,
1050 DIRTY_MEMORY_BLOCK_SIZE - offset);
1052 dirty |= bitmap_test_and_clear_atomic(blocks->blocks[idx],
1053 offset, num);
1054 page += num;
1057 mr_offset = (ram_addr_t)(start_page << TARGET_PAGE_BITS) - ramblock->offset;
1058 mr_size = (end - start_page) << TARGET_PAGE_BITS;
1059 memory_region_clear_dirty_bitmap(ramblock->mr, mr_offset, mr_size);
1062 if (dirty && tcg_enabled()) {
1063 tlb_reset_dirty_range_all(start, length);
1066 return dirty;
1069 DirtyBitmapSnapshot *cpu_physical_memory_snapshot_and_clear_dirty
1070 (MemoryRegion *mr, hwaddr offset, hwaddr length, unsigned client)
1072 DirtyMemoryBlocks *blocks;
1073 ram_addr_t start = memory_region_get_ram_addr(mr) + offset;
1074 unsigned long align = 1UL << (TARGET_PAGE_BITS + BITS_PER_LEVEL);
1075 ram_addr_t first = QEMU_ALIGN_DOWN(start, align);
1076 ram_addr_t last = QEMU_ALIGN_UP(start + length, align);
1077 DirtyBitmapSnapshot *snap;
1078 unsigned long page, end, dest;
1080 snap = g_malloc0(sizeof(*snap) +
1081 ((last - first) >> (TARGET_PAGE_BITS + 3)));
1082 snap->start = first;
1083 snap->end = last;
1085 page = first >> TARGET_PAGE_BITS;
1086 end = last >> TARGET_PAGE_BITS;
1087 dest = 0;
1089 WITH_RCU_READ_LOCK_GUARD() {
1090 blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
1092 while (page < end) {
1093 unsigned long idx = page / DIRTY_MEMORY_BLOCK_SIZE;
1094 unsigned long offset = page % DIRTY_MEMORY_BLOCK_SIZE;
1095 unsigned long num = MIN(end - page,
1096 DIRTY_MEMORY_BLOCK_SIZE - offset);
1098 assert(QEMU_IS_ALIGNED(offset, (1 << BITS_PER_LEVEL)));
1099 assert(QEMU_IS_ALIGNED(num, (1 << BITS_PER_LEVEL)));
1100 offset >>= BITS_PER_LEVEL;
1102 bitmap_copy_and_clear_atomic(snap->dirty + dest,
1103 blocks->blocks[idx] + offset,
1104 num);
1105 page += num;
1106 dest += num >> BITS_PER_LEVEL;
1110 if (tcg_enabled()) {
1111 tlb_reset_dirty_range_all(start, length);
1114 memory_region_clear_dirty_bitmap(mr, offset, length);
1116 return snap;
1119 bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
1120 ram_addr_t start,
1121 ram_addr_t length)
1123 unsigned long page, end;
1125 assert(start >= snap->start);
1126 assert(start + length <= snap->end);
1128 end = TARGET_PAGE_ALIGN(start + length - snap->start) >> TARGET_PAGE_BITS;
1129 page = (start - snap->start) >> TARGET_PAGE_BITS;
1131 while (page < end) {
1132 if (test_bit(page, snap->dirty)) {
1133 return true;
1135 page++;
1137 return false;
1140 /* Called from RCU critical section */
1141 hwaddr memory_region_section_get_iotlb(CPUState *cpu,
1142 MemoryRegionSection *section)
1144 AddressSpaceDispatch *d = flatview_to_dispatch(section->fv);
1145 return section - d->map.sections;
1148 static int subpage_register(subpage_t *mmio, uint32_t start, uint32_t end,
1149 uint16_t section);
1150 static subpage_t *subpage_init(FlatView *fv, hwaddr base);
1152 static uint16_t phys_section_add(PhysPageMap *map,
1153 MemoryRegionSection *section)
1155 /* The physical section number is ORed with a page-aligned
1156 * pointer to produce the iotlb entries. Thus it should
1157 * never overflow into the page-aligned value.
1159 assert(map->sections_nb < TARGET_PAGE_SIZE);
1161 if (map->sections_nb == map->sections_nb_alloc) {
1162 map->sections_nb_alloc = MAX(map->sections_nb_alloc * 2, 16);
1163 map->sections = g_renew(MemoryRegionSection, map->sections,
1164 map->sections_nb_alloc);
1166 map->sections[map->sections_nb] = *section;
1167 memory_region_ref(section->mr);
1168 return map->sections_nb++;
1171 static void phys_section_destroy(MemoryRegion *mr)
1173 bool have_sub_page = mr->subpage;
1175 memory_region_unref(mr);
1177 if (have_sub_page) {
1178 subpage_t *subpage = container_of(mr, subpage_t, iomem);
1179 object_unref(OBJECT(&subpage->iomem));
1180 g_free(subpage);
1184 static void phys_sections_free(PhysPageMap *map)
1186 while (map->sections_nb > 0) {
1187 MemoryRegionSection *section = &map->sections[--map->sections_nb];
1188 phys_section_destroy(section->mr);
1190 g_free(map->sections);
1191 g_free(map->nodes);
1194 static void register_subpage(FlatView *fv, MemoryRegionSection *section)
1196 AddressSpaceDispatch *d = flatview_to_dispatch(fv);
1197 subpage_t *subpage;
1198 hwaddr base = section->offset_within_address_space
1199 & TARGET_PAGE_MASK;
1200 MemoryRegionSection *existing = phys_page_find(d, base);
1201 MemoryRegionSection subsection = {
1202 .offset_within_address_space = base,
1203 .size = int128_make64(TARGET_PAGE_SIZE),
1205 hwaddr start, end;
1207 assert(existing->mr->subpage || existing->mr == &io_mem_unassigned);
1209 if (!(existing->mr->subpage)) {
1210 subpage = subpage_init(fv, base);
1211 subsection.fv = fv;
1212 subsection.mr = &subpage->iomem;
1213 phys_page_set(d, base >> TARGET_PAGE_BITS, 1,
1214 phys_section_add(&d->map, &subsection));
1215 } else {
1216 subpage = container_of(existing->mr, subpage_t, iomem);
1218 start = section->offset_within_address_space & ~TARGET_PAGE_MASK;
1219 end = start + int128_get64(section->size) - 1;
1220 subpage_register(subpage, start, end,
1221 phys_section_add(&d->map, section));
1225 static void register_multipage(FlatView *fv,
1226 MemoryRegionSection *section)
1228 AddressSpaceDispatch *d = flatview_to_dispatch(fv);
1229 hwaddr start_addr = section->offset_within_address_space;
1230 uint16_t section_index = phys_section_add(&d->map, section);
1231 uint64_t num_pages = int128_get64(int128_rshift(section->size,
1232 TARGET_PAGE_BITS));
1234 assert(num_pages);
1235 phys_page_set(d, start_addr >> TARGET_PAGE_BITS, num_pages, section_index);
1239 * The range in *section* may look like this:
1241 * |s|PPPPPPP|s|
1243 * where s stands for subpage and P for page.
1245 void flatview_add_to_dispatch(FlatView *fv, MemoryRegionSection *section)
1247 MemoryRegionSection remain = *section;
1248 Int128 page_size = int128_make64(TARGET_PAGE_SIZE);
1250 /* register first subpage */
1251 if (remain.offset_within_address_space & ~TARGET_PAGE_MASK) {
1252 uint64_t left = TARGET_PAGE_ALIGN(remain.offset_within_address_space)
1253 - remain.offset_within_address_space;
1255 MemoryRegionSection now = remain;
1256 now.size = int128_min(int128_make64(left), now.size);
1257 register_subpage(fv, &now);
1258 if (int128_eq(remain.size, now.size)) {
1259 return;
1261 remain.size = int128_sub(remain.size, now.size);
1262 remain.offset_within_address_space += int128_get64(now.size);
1263 remain.offset_within_region += int128_get64(now.size);
1266 /* register whole pages */
1267 if (int128_ge(remain.size, page_size)) {
1268 MemoryRegionSection now = remain;
1269 now.size = int128_and(now.size, int128_neg(page_size));
1270 register_multipage(fv, &now);
1271 if (int128_eq(remain.size, now.size)) {
1272 return;
1274 remain.size = int128_sub(remain.size, now.size);
1275 remain.offset_within_address_space += int128_get64(now.size);
1276 remain.offset_within_region += int128_get64(now.size);
1279 /* register last subpage */
1280 register_subpage(fv, &remain);
1283 void qemu_flush_coalesced_mmio_buffer(void)
1285 if (kvm_enabled())
1286 kvm_flush_coalesced_mmio_buffer();
1289 void qemu_mutex_lock_ramlist(void)
1291 qemu_mutex_lock(&ram_list.mutex);
1294 void qemu_mutex_unlock_ramlist(void)
1296 qemu_mutex_unlock(&ram_list.mutex);
1299 GString *ram_block_format(void)
1301 RAMBlock *block;
1302 char *psize;
1303 GString *buf = g_string_new("");
1305 RCU_READ_LOCK_GUARD();
1306 g_string_append_printf(buf, "%24s %8s %18s %18s %18s\n",
1307 "Block Name", "PSize", "Offset", "Used", "Total");
1308 RAMBLOCK_FOREACH(block) {
1309 psize = size_to_str(block->page_size);
1310 g_string_append_printf(buf, "%24s %8s 0x%016" PRIx64 " 0x%016" PRIx64
1311 " 0x%016" PRIx64 "\n", block->idstr, psize,
1312 (uint64_t)block->offset,
1313 (uint64_t)block->used_length,
1314 (uint64_t)block->max_length);
1315 g_free(psize);
1318 return buf;
1321 #ifdef __linux__
1323 * FIXME TOCTTOU: this iterates over memory backends' mem-path, which
1324 * may or may not name the same files / on the same filesystem now as
1325 * when we actually open and map them. Iterate over the file
1326 * descriptors instead, and use qemu_fd_getpagesize().
1328 static int find_min_backend_pagesize(Object *obj, void *opaque)
1330 long *hpsize_min = opaque;
1332 if (object_dynamic_cast(obj, TYPE_MEMORY_BACKEND)) {
1333 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
1334 long hpsize = host_memory_backend_pagesize(backend);
1336 if (host_memory_backend_is_mapped(backend) && (hpsize < *hpsize_min)) {
1337 *hpsize_min = hpsize;
1341 return 0;
1344 static int find_max_backend_pagesize(Object *obj, void *opaque)
1346 long *hpsize_max = opaque;
1348 if (object_dynamic_cast(obj, TYPE_MEMORY_BACKEND)) {
1349 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
1350 long hpsize = host_memory_backend_pagesize(backend);
1352 if (host_memory_backend_is_mapped(backend) && (hpsize > *hpsize_max)) {
1353 *hpsize_max = hpsize;
1357 return 0;
1361 * TODO: We assume right now that all mapped host memory backends are
1362 * used as RAM, however some might be used for different purposes.
1364 long qemu_minrampagesize(void)
1366 long hpsize = LONG_MAX;
1367 Object *memdev_root = object_resolve_path("/objects", NULL);
1369 object_child_foreach(memdev_root, find_min_backend_pagesize, &hpsize);
1370 return hpsize;
1373 long qemu_maxrampagesize(void)
1375 long pagesize = 0;
1376 Object *memdev_root = object_resolve_path("/objects", NULL);
1378 object_child_foreach(memdev_root, find_max_backend_pagesize, &pagesize);
1379 return pagesize;
1381 #else
1382 long qemu_minrampagesize(void)
1384 return qemu_real_host_page_size;
1386 long qemu_maxrampagesize(void)
1388 return qemu_real_host_page_size;
1390 #endif
1392 #ifdef CONFIG_POSIX
1393 static int64_t get_file_size(int fd)
1395 int64_t size;
1396 #if defined(__linux__)
1397 struct stat st;
1399 if (fstat(fd, &st) < 0) {
1400 return -errno;
1403 /* Special handling for devdax character devices */
1404 if (S_ISCHR(st.st_mode)) {
1405 g_autofree char *subsystem_path = NULL;
1406 g_autofree char *subsystem = NULL;
1408 subsystem_path = g_strdup_printf("/sys/dev/char/%d:%d/subsystem",
1409 major(st.st_rdev), minor(st.st_rdev));
1410 subsystem = g_file_read_link(subsystem_path, NULL);
1412 if (subsystem && g_str_has_suffix(subsystem, "/dax")) {
1413 g_autofree char *size_path = NULL;
1414 g_autofree char *size_str = NULL;
1416 size_path = g_strdup_printf("/sys/dev/char/%d:%d/size",
1417 major(st.st_rdev), minor(st.st_rdev));
1419 if (g_file_get_contents(size_path, &size_str, NULL, NULL)) {
1420 return g_ascii_strtoll(size_str, NULL, 0);
1424 #endif /* defined(__linux__) */
1426 /* st.st_size may be zero for special files yet lseek(2) works */
1427 size = lseek(fd, 0, SEEK_END);
1428 if (size < 0) {
1429 return -errno;
1431 return size;
1434 static int64_t get_file_align(int fd)
1436 int64_t align = -1;
1437 #if defined(__linux__) && defined(CONFIG_LIBDAXCTL)
1438 struct stat st;
1440 if (fstat(fd, &st) < 0) {
1441 return -errno;
1444 /* Special handling for devdax character devices */
1445 if (S_ISCHR(st.st_mode)) {
1446 g_autofree char *path = NULL;
1447 g_autofree char *rpath = NULL;
1448 struct daxctl_ctx *ctx;
1449 struct daxctl_region *region;
1450 int rc = 0;
1452 path = g_strdup_printf("/sys/dev/char/%d:%d",
1453 major(st.st_rdev), minor(st.st_rdev));
1454 rpath = realpath(path, NULL);
1455 if (!rpath) {
1456 return -errno;
1459 rc = daxctl_new(&ctx);
1460 if (rc) {
1461 return -1;
1464 daxctl_region_foreach(ctx, region) {
1465 if (strstr(rpath, daxctl_region_get_path(region))) {
1466 align = daxctl_region_get_align(region);
1467 break;
1470 daxctl_unref(ctx);
1472 #endif /* defined(__linux__) && defined(CONFIG_LIBDAXCTL) */
1474 return align;
1477 static int file_ram_open(const char *path,
1478 const char *region_name,
1479 bool readonly,
1480 bool *created,
1481 Error **errp)
1483 char *filename;
1484 char *sanitized_name;
1485 char *c;
1486 int fd = -1;
1488 *created = false;
1489 for (;;) {
1490 fd = open(path, readonly ? O_RDONLY : O_RDWR);
1491 if (fd >= 0) {
1492 /* @path names an existing file, use it */
1493 break;
1495 if (errno == ENOENT) {
1496 /* @path names a file that doesn't exist, create it */
1497 fd = open(path, O_RDWR | O_CREAT | O_EXCL, 0644);
1498 if (fd >= 0) {
1499 *created = true;
1500 break;
1502 } else if (errno == EISDIR) {
1503 /* @path names a directory, create a file there */
1504 /* Make name safe to use with mkstemp by replacing '/' with '_'. */
1505 sanitized_name = g_strdup(region_name);
1506 for (c = sanitized_name; *c != '\0'; c++) {
1507 if (*c == '/') {
1508 *c = '_';
1512 filename = g_strdup_printf("%s/qemu_back_mem.%s.XXXXXX", path,
1513 sanitized_name);
1514 g_free(sanitized_name);
1516 fd = mkstemp(filename);
1517 if (fd >= 0) {
1518 unlink(filename);
1519 g_free(filename);
1520 break;
1522 g_free(filename);
1524 if (errno != EEXIST && errno != EINTR) {
1525 error_setg_errno(errp, errno,
1526 "can't open backing store %s for guest RAM",
1527 path);
1528 return -1;
1531 * Try again on EINTR and EEXIST. The latter happens when
1532 * something else creates the file between our two open().
1536 return fd;
1539 static void *file_ram_alloc(RAMBlock *block,
1540 ram_addr_t memory,
1541 int fd,
1542 bool readonly,
1543 bool truncate,
1544 off_t offset,
1545 Error **errp)
1547 uint32_t qemu_map_flags;
1548 void *area;
1550 block->page_size = qemu_fd_getpagesize(fd);
1551 if (block->mr->align % block->page_size) {
1552 error_setg(errp, "alignment 0x%" PRIx64
1553 " must be multiples of page size 0x%zx",
1554 block->mr->align, block->page_size);
1555 return NULL;
1556 } else if (block->mr->align && !is_power_of_2(block->mr->align)) {
1557 error_setg(errp, "alignment 0x%" PRIx64
1558 " must be a power of two", block->mr->align);
1559 return NULL;
1561 block->mr->align = MAX(block->page_size, block->mr->align);
1562 #if defined(__s390x__)
1563 if (kvm_enabled()) {
1564 block->mr->align = MAX(block->mr->align, QEMU_VMALLOC_ALIGN);
1566 #endif
1568 if (memory < block->page_size) {
1569 error_setg(errp, "memory size 0x" RAM_ADDR_FMT " must be equal to "
1570 "or larger than page size 0x%zx",
1571 memory, block->page_size);
1572 return NULL;
1575 memory = ROUND_UP(memory, block->page_size);
1578 * ftruncate is not supported by hugetlbfs in older
1579 * hosts, so don't bother bailing out on errors.
1580 * If anything goes wrong with it under other filesystems,
1581 * mmap will fail.
1583 * Do not truncate the non-empty backend file to avoid corrupting
1584 * the existing data in the file. Disabling shrinking is not
1585 * enough. For example, the current vNVDIMM implementation stores
1586 * the guest NVDIMM labels at the end of the backend file. If the
1587 * backend file is later extended, QEMU will not be able to find
1588 * those labels. Therefore, extending the non-empty backend file
1589 * is disabled as well.
1591 if (truncate && ftruncate(fd, memory)) {
1592 perror("ftruncate");
1595 qemu_map_flags = readonly ? QEMU_MAP_READONLY : 0;
1596 qemu_map_flags |= (block->flags & RAM_SHARED) ? QEMU_MAP_SHARED : 0;
1597 qemu_map_flags |= (block->flags & RAM_PMEM) ? QEMU_MAP_SYNC : 0;
1598 qemu_map_flags |= (block->flags & RAM_NORESERVE) ? QEMU_MAP_NORESERVE : 0;
1599 area = qemu_ram_mmap(fd, memory, block->mr->align, qemu_map_flags, offset);
1600 if (area == MAP_FAILED) {
1601 error_setg_errno(errp, errno,
1602 "unable to map backing store for guest RAM");
1603 return NULL;
1606 block->fd = fd;
1607 return area;
1609 #endif
1611 /* Allocate space within the ram_addr_t space that governs the
1612 * dirty bitmaps.
1613 * Called with the ramlist lock held.
1615 static ram_addr_t find_ram_offset(ram_addr_t size)
1617 RAMBlock *block, *next_block;
1618 ram_addr_t offset = RAM_ADDR_MAX, mingap = RAM_ADDR_MAX;
1620 assert(size != 0); /* it would hand out same offset multiple times */
1622 if (QLIST_EMPTY_RCU(&ram_list.blocks)) {
1623 return 0;
1626 RAMBLOCK_FOREACH(block) {
1627 ram_addr_t candidate, next = RAM_ADDR_MAX;
1629 /* Align blocks to start on a 'long' in the bitmap
1630 * which makes the bitmap sync'ing take the fast path.
1632 candidate = block->offset + block->max_length;
1633 candidate = ROUND_UP(candidate, BITS_PER_LONG << TARGET_PAGE_BITS);
1635 /* Search for the closest following block
1636 * and find the gap.
1638 RAMBLOCK_FOREACH(next_block) {
1639 if (next_block->offset >= candidate) {
1640 next = MIN(next, next_block->offset);
1644 /* If it fits remember our place and remember the size
1645 * of gap, but keep going so that we might find a smaller
1646 * gap to fill so avoiding fragmentation.
1648 if (next - candidate >= size && next - candidate < mingap) {
1649 offset = candidate;
1650 mingap = next - candidate;
1653 trace_find_ram_offset_loop(size, candidate, offset, next, mingap);
1656 if (offset == RAM_ADDR_MAX) {
1657 fprintf(stderr, "Failed to find gap of requested size: %" PRIu64 "\n",
1658 (uint64_t)size);
1659 abort();
1662 trace_find_ram_offset(size, offset);
1664 return offset;
1667 static unsigned long last_ram_page(void)
1669 RAMBlock *block;
1670 ram_addr_t last = 0;
1672 RCU_READ_LOCK_GUARD();
1673 RAMBLOCK_FOREACH(block) {
1674 last = MAX(last, block->offset + block->max_length);
1676 return last >> TARGET_PAGE_BITS;
1679 static void qemu_ram_setup_dump(void *addr, ram_addr_t size)
1681 int ret;
1683 /* Use MADV_DONTDUMP, if user doesn't want the guest memory in the core */
1684 if (!machine_dump_guest_core(current_machine)) {
1685 ret = qemu_madvise(addr, size, QEMU_MADV_DONTDUMP);
1686 if (ret) {
1687 perror("qemu_madvise");
1688 fprintf(stderr, "madvise doesn't support MADV_DONTDUMP, "
1689 "but dump_guest_core=off specified\n");
1694 const char *qemu_ram_get_idstr(RAMBlock *rb)
1696 return rb->idstr;
1699 void *qemu_ram_get_host_addr(RAMBlock *rb)
1701 return rb->host;
1704 ram_addr_t qemu_ram_get_offset(RAMBlock *rb)
1706 return rb->offset;
1709 ram_addr_t qemu_ram_get_used_length(RAMBlock *rb)
1711 return rb->used_length;
1714 ram_addr_t qemu_ram_get_max_length(RAMBlock *rb)
1716 return rb->max_length;
1719 bool qemu_ram_is_shared(RAMBlock *rb)
1721 return rb->flags & RAM_SHARED;
1724 bool qemu_ram_is_noreserve(RAMBlock *rb)
1726 return rb->flags & RAM_NORESERVE;
1729 /* Note: Only set at the start of postcopy */
1730 bool qemu_ram_is_uf_zeroable(RAMBlock *rb)
1732 return rb->flags & RAM_UF_ZEROPAGE;
1735 void qemu_ram_set_uf_zeroable(RAMBlock *rb)
1737 rb->flags |= RAM_UF_ZEROPAGE;
1740 bool qemu_ram_is_migratable(RAMBlock *rb)
1742 return rb->flags & RAM_MIGRATABLE;
1745 void qemu_ram_set_migratable(RAMBlock *rb)
1747 rb->flags |= RAM_MIGRATABLE;
1750 void qemu_ram_unset_migratable(RAMBlock *rb)
1752 rb->flags &= ~RAM_MIGRATABLE;
1755 /* Called with iothread lock held. */
1756 void qemu_ram_set_idstr(RAMBlock *new_block, const char *name, DeviceState *dev)
1758 RAMBlock *block;
1760 assert(new_block);
1761 assert(!new_block->idstr[0]);
1763 if (dev) {
1764 char *id = qdev_get_dev_path(dev);
1765 if (id) {
1766 snprintf(new_block->idstr, sizeof(new_block->idstr), "%s/", id);
1767 g_free(id);
1770 pstrcat(new_block->idstr, sizeof(new_block->idstr), name);
1772 RCU_READ_LOCK_GUARD();
1773 RAMBLOCK_FOREACH(block) {
1774 if (block != new_block &&
1775 !strcmp(block->idstr, new_block->idstr)) {
1776 fprintf(stderr, "RAMBlock \"%s\" already registered, abort!\n",
1777 new_block->idstr);
1778 abort();
1783 /* Called with iothread lock held. */
1784 void qemu_ram_unset_idstr(RAMBlock *block)
1786 /* FIXME: arch_init.c assumes that this is not called throughout
1787 * migration. Ignore the problem since hot-unplug during migration
1788 * does not work anyway.
1790 if (block) {
1791 memset(block->idstr, 0, sizeof(block->idstr));
1795 size_t qemu_ram_pagesize(RAMBlock *rb)
1797 return rb->page_size;
1800 /* Returns the largest size of page in use */
1801 size_t qemu_ram_pagesize_largest(void)
1803 RAMBlock *block;
1804 size_t largest = 0;
1806 RAMBLOCK_FOREACH(block) {
1807 largest = MAX(largest, qemu_ram_pagesize(block));
1810 return largest;
1813 static int memory_try_enable_merging(void *addr, size_t len)
1815 if (!machine_mem_merge(current_machine)) {
1816 /* disabled by the user */
1817 return 0;
1820 return qemu_madvise(addr, len, QEMU_MADV_MERGEABLE);
1824 * Resizing RAM while migrating can result in the migration being canceled.
1825 * Care has to be taken if the guest might have already detected the memory.
1827 * As memory core doesn't know how is memory accessed, it is up to
1828 * resize callback to update device state and/or add assertions to detect
1829 * misuse, if necessary.
1831 int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp)
1833 const ram_addr_t oldsize = block->used_length;
1834 const ram_addr_t unaligned_size = newsize;
1836 assert(block);
1838 newsize = HOST_PAGE_ALIGN(newsize);
1840 if (block->used_length == newsize) {
1842 * We don't have to resize the ram block (which only knows aligned
1843 * sizes), however, we have to notify if the unaligned size changed.
1845 if (unaligned_size != memory_region_size(block->mr)) {
1846 memory_region_set_size(block->mr, unaligned_size);
1847 if (block->resized) {
1848 block->resized(block->idstr, unaligned_size, block->host);
1851 return 0;
1854 if (!(block->flags & RAM_RESIZEABLE)) {
1855 error_setg_errno(errp, EINVAL,
1856 "Size mismatch: %s: 0x" RAM_ADDR_FMT
1857 " != 0x" RAM_ADDR_FMT, block->idstr,
1858 newsize, block->used_length);
1859 return -EINVAL;
1862 if (block->max_length < newsize) {
1863 error_setg_errno(errp, EINVAL,
1864 "Size too large: %s: 0x" RAM_ADDR_FMT
1865 " > 0x" RAM_ADDR_FMT, block->idstr,
1866 newsize, block->max_length);
1867 return -EINVAL;
1870 /* Notify before modifying the ram block and touching the bitmaps. */
1871 if (block->host) {
1872 ram_block_notify_resize(block->host, oldsize, newsize);
1875 cpu_physical_memory_clear_dirty_range(block->offset, block->used_length);
1876 block->used_length = newsize;
1877 cpu_physical_memory_set_dirty_range(block->offset, block->used_length,
1878 DIRTY_CLIENTS_ALL);
1879 memory_region_set_size(block->mr, unaligned_size);
1880 if (block->resized) {
1881 block->resized(block->idstr, unaligned_size, block->host);
1883 return 0;
1887 * Trigger sync on the given ram block for range [start, start + length]
1888 * with the backing store if one is available.
1889 * Otherwise no-op.
1890 * @Note: this is supposed to be a synchronous op.
1892 void qemu_ram_msync(RAMBlock *block, ram_addr_t start, ram_addr_t length)
1894 /* The requested range should fit in within the block range */
1895 g_assert((start + length) <= block->used_length);
1897 #ifdef CONFIG_LIBPMEM
1898 /* The lack of support for pmem should not block the sync */
1899 if (ramblock_is_pmem(block)) {
1900 void *addr = ramblock_ptr(block, start);
1901 pmem_persist(addr, length);
1902 return;
1904 #endif
1905 if (block->fd >= 0) {
1907 * Case there is no support for PMEM or the memory has not been
1908 * specified as persistent (or is not one) - use the msync.
1909 * Less optimal but still achieves the same goal
1911 void *addr = ramblock_ptr(block, start);
1912 if (qemu_msync(addr, length, block->fd)) {
1913 warn_report("%s: failed to sync memory range: start: "
1914 RAM_ADDR_FMT " length: " RAM_ADDR_FMT,
1915 __func__, start, length);
1920 /* Called with ram_list.mutex held */
1921 static void dirty_memory_extend(ram_addr_t old_ram_size,
1922 ram_addr_t new_ram_size)
1924 ram_addr_t old_num_blocks = DIV_ROUND_UP(old_ram_size,
1925 DIRTY_MEMORY_BLOCK_SIZE);
1926 ram_addr_t new_num_blocks = DIV_ROUND_UP(new_ram_size,
1927 DIRTY_MEMORY_BLOCK_SIZE);
1928 int i;
1930 /* Only need to extend if block count increased */
1931 if (new_num_blocks <= old_num_blocks) {
1932 return;
1935 for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
1936 DirtyMemoryBlocks *old_blocks;
1937 DirtyMemoryBlocks *new_blocks;
1938 int j;
1940 old_blocks = qatomic_rcu_read(&ram_list.dirty_memory[i]);
1941 new_blocks = g_malloc(sizeof(*new_blocks) +
1942 sizeof(new_blocks->blocks[0]) * new_num_blocks);
1944 if (old_num_blocks) {
1945 memcpy(new_blocks->blocks, old_blocks->blocks,
1946 old_num_blocks * sizeof(old_blocks->blocks[0]));
1949 for (j = old_num_blocks; j < new_num_blocks; j++) {
1950 new_blocks->blocks[j] = bitmap_new(DIRTY_MEMORY_BLOCK_SIZE);
1953 qatomic_rcu_set(&ram_list.dirty_memory[i], new_blocks);
1955 if (old_blocks) {
1956 g_free_rcu(old_blocks, rcu);
1961 static void ram_block_add(RAMBlock *new_block, Error **errp)
1963 const bool noreserve = qemu_ram_is_noreserve(new_block);
1964 const bool shared = qemu_ram_is_shared(new_block);
1965 RAMBlock *block;
1966 RAMBlock *last_block = NULL;
1967 ram_addr_t old_ram_size, new_ram_size;
1968 Error *err = NULL;
1970 old_ram_size = last_ram_page();
1972 qemu_mutex_lock_ramlist();
1973 new_block->offset = find_ram_offset(new_block->max_length);
1975 if (!new_block->host) {
1976 if (xen_enabled()) {
1977 xen_ram_alloc(new_block->offset, new_block->max_length,
1978 new_block->mr, &err);
1979 if (err) {
1980 error_propagate(errp, err);
1981 qemu_mutex_unlock_ramlist();
1982 return;
1984 } else {
1985 new_block->host = qemu_anon_ram_alloc(new_block->max_length,
1986 &new_block->mr->align,
1987 shared, noreserve);
1988 if (!new_block->host) {
1989 error_setg_errno(errp, errno,
1990 "cannot set up guest memory '%s'",
1991 memory_region_name(new_block->mr));
1992 qemu_mutex_unlock_ramlist();
1993 return;
1995 memory_try_enable_merging(new_block->host, new_block->max_length);
1999 new_ram_size = MAX(old_ram_size,
2000 (new_block->offset + new_block->max_length) >> TARGET_PAGE_BITS);
2001 if (new_ram_size > old_ram_size) {
2002 dirty_memory_extend(old_ram_size, new_ram_size);
2004 /* Keep the list sorted from biggest to smallest block. Unlike QTAILQ,
2005 * QLIST (which has an RCU-friendly variant) does not have insertion at
2006 * tail, so save the last element in last_block.
2008 RAMBLOCK_FOREACH(block) {
2009 last_block = block;
2010 if (block->max_length < new_block->max_length) {
2011 break;
2014 if (block) {
2015 QLIST_INSERT_BEFORE_RCU(block, new_block, next);
2016 } else if (last_block) {
2017 QLIST_INSERT_AFTER_RCU(last_block, new_block, next);
2018 } else { /* list is empty */
2019 QLIST_INSERT_HEAD_RCU(&ram_list.blocks, new_block, next);
2021 ram_list.mru_block = NULL;
2023 /* Write list before version */
2024 smp_wmb();
2025 ram_list.version++;
2026 qemu_mutex_unlock_ramlist();
2028 cpu_physical_memory_set_dirty_range(new_block->offset,
2029 new_block->used_length,
2030 DIRTY_CLIENTS_ALL);
2032 if (new_block->host) {
2033 qemu_ram_setup_dump(new_block->host, new_block->max_length);
2034 qemu_madvise(new_block->host, new_block->max_length, QEMU_MADV_HUGEPAGE);
2036 * MADV_DONTFORK is also needed by KVM in absence of synchronous MMU
2037 * Configure it unless the machine is a qtest server, in which case
2038 * KVM is not used and it may be forked (eg for fuzzing purposes).
2040 if (!qtest_enabled()) {
2041 qemu_madvise(new_block->host, new_block->max_length,
2042 QEMU_MADV_DONTFORK);
2044 ram_block_notify_add(new_block->host, new_block->used_length,
2045 new_block->max_length);
2049 #ifdef CONFIG_POSIX
2050 RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
2051 uint32_t ram_flags, int fd, off_t offset,
2052 bool readonly, Error **errp)
2054 RAMBlock *new_block;
2055 Error *local_err = NULL;
2056 int64_t file_size, file_align;
2058 /* Just support these ram flags by now. */
2059 assert((ram_flags & ~(RAM_SHARED | RAM_PMEM | RAM_NORESERVE |
2060 RAM_PROTECTED)) == 0);
2062 if (xen_enabled()) {
2063 error_setg(errp, "-mem-path not supported with Xen");
2064 return NULL;
2067 if (kvm_enabled() && !kvm_has_sync_mmu()) {
2068 error_setg(errp,
2069 "host lacks kvm mmu notifiers, -mem-path unsupported");
2070 return NULL;
2073 size = HOST_PAGE_ALIGN(size);
2074 file_size = get_file_size(fd);
2075 if (file_size > 0 && file_size < size) {
2076 error_setg(errp, "backing store size 0x%" PRIx64
2077 " does not match 'size' option 0x" RAM_ADDR_FMT,
2078 file_size, size);
2079 return NULL;
2082 file_align = get_file_align(fd);
2083 if (file_align > 0 && file_align > mr->align) {
2084 error_setg(errp, "backing store align 0x%" PRIx64
2085 " is larger than 'align' option 0x%" PRIx64,
2086 file_align, mr->align);
2087 return NULL;
2090 new_block = g_malloc0(sizeof(*new_block));
2091 new_block->mr = mr;
2092 new_block->used_length = size;
2093 new_block->max_length = size;
2094 new_block->flags = ram_flags;
2095 new_block->host = file_ram_alloc(new_block, size, fd, readonly,
2096 !file_size, offset, errp);
2097 if (!new_block->host) {
2098 g_free(new_block);
2099 return NULL;
2102 ram_block_add(new_block, &local_err);
2103 if (local_err) {
2104 g_free(new_block);
2105 error_propagate(errp, local_err);
2106 return NULL;
2108 return new_block;
2113 RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
2114 uint32_t ram_flags, const char *mem_path,
2115 bool readonly, Error **errp)
2117 int fd;
2118 bool created;
2119 RAMBlock *block;
2121 fd = file_ram_open(mem_path, memory_region_name(mr), readonly, &created,
2122 errp);
2123 if (fd < 0) {
2124 return NULL;
2127 block = qemu_ram_alloc_from_fd(size, mr, ram_flags, fd, 0, readonly, errp);
2128 if (!block) {
2129 if (created) {
2130 unlink(mem_path);
2132 close(fd);
2133 return NULL;
2136 return block;
2138 #endif
2140 static
2141 RAMBlock *qemu_ram_alloc_internal(ram_addr_t size, ram_addr_t max_size,
2142 void (*resized)(const char*,
2143 uint64_t length,
2144 void *host),
2145 void *host, uint32_t ram_flags,
2146 MemoryRegion *mr, Error **errp)
2148 RAMBlock *new_block;
2149 Error *local_err = NULL;
2151 assert((ram_flags & ~(RAM_SHARED | RAM_RESIZEABLE | RAM_PREALLOC |
2152 RAM_NORESERVE)) == 0);
2153 assert(!host ^ (ram_flags & RAM_PREALLOC));
2155 size = HOST_PAGE_ALIGN(size);
2156 max_size = HOST_PAGE_ALIGN(max_size);
2157 new_block = g_malloc0(sizeof(*new_block));
2158 new_block->mr = mr;
2159 new_block->resized = resized;
2160 new_block->used_length = size;
2161 new_block->max_length = max_size;
2162 assert(max_size >= size);
2163 new_block->fd = -1;
2164 new_block->page_size = qemu_real_host_page_size;
2165 new_block->host = host;
2166 new_block->flags = ram_flags;
2167 ram_block_add(new_block, &local_err);
2168 if (local_err) {
2169 g_free(new_block);
2170 error_propagate(errp, local_err);
2171 return NULL;
2173 return new_block;
2176 RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
2177 MemoryRegion *mr, Error **errp)
2179 return qemu_ram_alloc_internal(size, size, NULL, host, RAM_PREALLOC, mr,
2180 errp);
2183 RAMBlock *qemu_ram_alloc(ram_addr_t size, uint32_t ram_flags,
2184 MemoryRegion *mr, Error **errp)
2186 assert((ram_flags & ~(RAM_SHARED | RAM_NORESERVE)) == 0);
2187 return qemu_ram_alloc_internal(size, size, NULL, NULL, ram_flags, mr, errp);
2190 RAMBlock *qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t maxsz,
2191 void (*resized)(const char*,
2192 uint64_t length,
2193 void *host),
2194 MemoryRegion *mr, Error **errp)
2196 return qemu_ram_alloc_internal(size, maxsz, resized, NULL,
2197 RAM_RESIZEABLE, mr, errp);
2200 static void reclaim_ramblock(RAMBlock *block)
2202 if (block->flags & RAM_PREALLOC) {
2204 } else if (xen_enabled()) {
2205 xen_invalidate_map_cache_entry(block->host);
2206 #ifndef _WIN32
2207 } else if (block->fd >= 0) {
2208 qemu_ram_munmap(block->fd, block->host, block->max_length);
2209 close(block->fd);
2210 #endif
2211 } else {
2212 qemu_anon_ram_free(block->host, block->max_length);
2214 g_free(block);
2217 void qemu_ram_free(RAMBlock *block)
2219 if (!block) {
2220 return;
2223 if (block->host) {
2224 ram_block_notify_remove(block->host, block->used_length,
2225 block->max_length);
2228 qemu_mutex_lock_ramlist();
2229 QLIST_REMOVE_RCU(block, next);
2230 ram_list.mru_block = NULL;
2231 /* Write list before version */
2232 smp_wmb();
2233 ram_list.version++;
2234 call_rcu(block, reclaim_ramblock, rcu);
2235 qemu_mutex_unlock_ramlist();
2238 #ifndef _WIN32
2239 void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)
2241 RAMBlock *block;
2242 ram_addr_t offset;
2243 int flags;
2244 void *area, *vaddr;
2246 RAMBLOCK_FOREACH(block) {
2247 offset = addr - block->offset;
2248 if (offset < block->max_length) {
2249 vaddr = ramblock_ptr(block, offset);
2250 if (block->flags & RAM_PREALLOC) {
2252 } else if (xen_enabled()) {
2253 abort();
2254 } else {
2255 flags = MAP_FIXED;
2256 flags |= block->flags & RAM_SHARED ?
2257 MAP_SHARED : MAP_PRIVATE;
2258 flags |= block->flags & RAM_NORESERVE ? MAP_NORESERVE : 0;
2259 if (block->fd >= 0) {
2260 area = mmap(vaddr, length, PROT_READ | PROT_WRITE,
2261 flags, block->fd, offset);
2262 } else {
2263 flags |= MAP_ANONYMOUS;
2264 area = mmap(vaddr, length, PROT_READ | PROT_WRITE,
2265 flags, -1, 0);
2267 if (area != vaddr) {
2268 error_report("Could not remap addr: "
2269 RAM_ADDR_FMT "@" RAM_ADDR_FMT "",
2270 length, addr);
2271 exit(1);
2273 memory_try_enable_merging(vaddr, length);
2274 qemu_ram_setup_dump(vaddr, length);
2279 #endif /* !_WIN32 */
2281 /* Return a host pointer to ram allocated with qemu_ram_alloc.
2282 * This should not be used for general purpose DMA. Use address_space_map
2283 * or address_space_rw instead. For local memory (e.g. video ram) that the
2284 * device owns, use memory_region_get_ram_ptr.
2286 * Called within RCU critical section.
2288 void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr)
2290 RAMBlock *block = ram_block;
2292 if (block == NULL) {
2293 block = qemu_get_ram_block(addr);
2294 addr -= block->offset;
2297 if (xen_enabled() && block->host == NULL) {
2298 /* We need to check if the requested address is in the RAM
2299 * because we don't want to map the entire memory in QEMU.
2300 * In that case just map until the end of the page.
2302 if (block->offset == 0) {
2303 return xen_map_cache(addr, 0, 0, false);
2306 block->host = xen_map_cache(block->offset, block->max_length, 1, false);
2308 return ramblock_ptr(block, addr);
2311 /* Return a host pointer to guest's ram. Similar to qemu_map_ram_ptr
2312 * but takes a size argument.
2314 * Called within RCU critical section.
2316 static void *qemu_ram_ptr_length(RAMBlock *ram_block, ram_addr_t addr,
2317 hwaddr *size, bool lock)
2319 RAMBlock *block = ram_block;
2320 if (*size == 0) {
2321 return NULL;
2324 if (block == NULL) {
2325 block = qemu_get_ram_block(addr);
2326 addr -= block->offset;
2328 *size = MIN(*size, block->max_length - addr);
2330 if (xen_enabled() && block->host == NULL) {
2331 /* We need to check if the requested address is in the RAM
2332 * because we don't want to map the entire memory in QEMU.
2333 * In that case just map the requested area.
2335 if (block->offset == 0) {
2336 return xen_map_cache(addr, *size, lock, lock);
2339 block->host = xen_map_cache(block->offset, block->max_length, 1, lock);
2342 return ramblock_ptr(block, addr);
2345 /* Return the offset of a hostpointer within a ramblock */
2346 ram_addr_t qemu_ram_block_host_offset(RAMBlock *rb, void *host)
2348 ram_addr_t res = (uint8_t *)host - (uint8_t *)rb->host;
2349 assert((uintptr_t)host >= (uintptr_t)rb->host);
2350 assert(res < rb->max_length);
2352 return res;
2356 * Translates a host ptr back to a RAMBlock, a ram_addr and an offset
2357 * in that RAMBlock.
2359 * ptr: Host pointer to look up
2360 * round_offset: If true round the result offset down to a page boundary
2361 * *ram_addr: set to result ram_addr
2362 * *offset: set to result offset within the RAMBlock
2364 * Returns: RAMBlock (or NULL if not found)
2366 * By the time this function returns, the returned pointer is not protected
2367 * by RCU anymore. If the caller is not within an RCU critical section and
2368 * does not hold the iothread lock, it must have other means of protecting the
2369 * pointer, such as a reference to the region that includes the incoming
2370 * ram_addr_t.
2372 RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset,
2373 ram_addr_t *offset)
2375 RAMBlock *block;
2376 uint8_t *host = ptr;
2378 if (xen_enabled()) {
2379 ram_addr_t ram_addr;
2380 RCU_READ_LOCK_GUARD();
2381 ram_addr = xen_ram_addr_from_mapcache(ptr);
2382 block = qemu_get_ram_block(ram_addr);
2383 if (block) {
2384 *offset = ram_addr - block->offset;
2386 return block;
2389 RCU_READ_LOCK_GUARD();
2390 block = qatomic_rcu_read(&ram_list.mru_block);
2391 if (block && block->host && host - block->host < block->max_length) {
2392 goto found;
2395 RAMBLOCK_FOREACH(block) {
2396 /* This case append when the block is not mapped. */
2397 if (block->host == NULL) {
2398 continue;
2400 if (host - block->host < block->max_length) {
2401 goto found;
2405 return NULL;
2407 found:
2408 *offset = (host - block->host);
2409 if (round_offset) {
2410 *offset &= TARGET_PAGE_MASK;
2412 return block;
2416 * Finds the named RAMBlock
2418 * name: The name of RAMBlock to find
2420 * Returns: RAMBlock (or NULL if not found)
2422 RAMBlock *qemu_ram_block_by_name(const char *name)
2424 RAMBlock *block;
2426 RAMBLOCK_FOREACH(block) {
2427 if (!strcmp(name, block->idstr)) {
2428 return block;
2432 return NULL;
2435 /* Some of the softmmu routines need to translate from a host pointer
2436 (typically a TLB entry) back to a ram offset. */
2437 ram_addr_t qemu_ram_addr_from_host(void *ptr)
2439 RAMBlock *block;
2440 ram_addr_t offset;
2442 block = qemu_ram_block_from_host(ptr, false, &offset);
2443 if (!block) {
2444 return RAM_ADDR_INVALID;
2447 return block->offset + offset;
2450 static MemTxResult flatview_read(FlatView *fv, hwaddr addr,
2451 MemTxAttrs attrs, void *buf, hwaddr len);
2452 static MemTxResult flatview_write(FlatView *fv, hwaddr addr, MemTxAttrs attrs,
2453 const void *buf, hwaddr len);
2454 static bool flatview_access_valid(FlatView *fv, hwaddr addr, hwaddr len,
2455 bool is_write, MemTxAttrs attrs);
2457 static MemTxResult subpage_read(void *opaque, hwaddr addr, uint64_t *data,
2458 unsigned len, MemTxAttrs attrs)
2460 subpage_t *subpage = opaque;
2461 uint8_t buf[8];
2462 MemTxResult res;
2464 #if defined(DEBUG_SUBPAGE)
2465 printf("%s: subpage %p len %u addr " TARGET_FMT_plx "\n", __func__,
2466 subpage, len, addr);
2467 #endif
2468 res = flatview_read(subpage->fv, addr + subpage->base, attrs, buf, len);
2469 if (res) {
2470 return res;
2472 *data = ldn_p(buf, len);
2473 return MEMTX_OK;
2476 static MemTxResult subpage_write(void *opaque, hwaddr addr,
2477 uint64_t value, unsigned len, MemTxAttrs attrs)
2479 subpage_t *subpage = opaque;
2480 uint8_t buf[8];
2482 #if defined(DEBUG_SUBPAGE)
2483 printf("%s: subpage %p len %u addr " TARGET_FMT_plx
2484 " value %"PRIx64"\n",
2485 __func__, subpage, len, addr, value);
2486 #endif
2487 stn_p(buf, len, value);
2488 return flatview_write(subpage->fv, addr + subpage->base, attrs, buf, len);
2491 static bool subpage_accepts(void *opaque, hwaddr addr,
2492 unsigned len, bool is_write,
2493 MemTxAttrs attrs)
2495 subpage_t *subpage = opaque;
2496 #if defined(DEBUG_SUBPAGE)
2497 printf("%s: subpage %p %c len %u addr " TARGET_FMT_plx "\n",
2498 __func__, subpage, is_write ? 'w' : 'r', len, addr);
2499 #endif
2501 return flatview_access_valid(subpage->fv, addr + subpage->base,
2502 len, is_write, attrs);
2505 static const MemoryRegionOps subpage_ops = {
2506 .read_with_attrs = subpage_read,
2507 .write_with_attrs = subpage_write,
2508 .impl.min_access_size = 1,
2509 .impl.max_access_size = 8,
2510 .valid.min_access_size = 1,
2511 .valid.max_access_size = 8,
2512 .valid.accepts = subpage_accepts,
2513 .endianness = DEVICE_NATIVE_ENDIAN,
2516 static int subpage_register(subpage_t *mmio, uint32_t start, uint32_t end,
2517 uint16_t section)
2519 int idx, eidx;
2521 if (start >= TARGET_PAGE_SIZE || end >= TARGET_PAGE_SIZE)
2522 return -1;
2523 idx = SUBPAGE_IDX(start);
2524 eidx = SUBPAGE_IDX(end);
2525 #if defined(DEBUG_SUBPAGE)
2526 printf("%s: %p start %08x end %08x idx %08x eidx %08x section %d\n",
2527 __func__, mmio, start, end, idx, eidx, section);
2528 #endif
2529 for (; idx <= eidx; idx++) {
2530 mmio->sub_section[idx] = section;
2533 return 0;
2536 static subpage_t *subpage_init(FlatView *fv, hwaddr base)
2538 subpage_t *mmio;
2540 /* mmio->sub_section is set to PHYS_SECTION_UNASSIGNED with g_malloc0 */
2541 mmio = g_malloc0(sizeof(subpage_t) + TARGET_PAGE_SIZE * sizeof(uint16_t));
2542 mmio->fv = fv;
2543 mmio->base = base;
2544 memory_region_init_io(&mmio->iomem, NULL, &subpage_ops, mmio,
2545 NULL, TARGET_PAGE_SIZE);
2546 mmio->iomem.subpage = true;
2547 #if defined(DEBUG_SUBPAGE)
2548 printf("%s: %p base " TARGET_FMT_plx " len %08x\n", __func__,
2549 mmio, base, TARGET_PAGE_SIZE);
2550 #endif
2552 return mmio;
2555 static uint16_t dummy_section(PhysPageMap *map, FlatView *fv, MemoryRegion *mr)
2557 assert(fv);
2558 MemoryRegionSection section = {
2559 .fv = fv,
2560 .mr = mr,
2561 .offset_within_address_space = 0,
2562 .offset_within_region = 0,
2563 .size = int128_2_64(),
2566 return phys_section_add(map, &section);
2569 MemoryRegionSection *iotlb_to_section(CPUState *cpu,
2570 hwaddr index, MemTxAttrs attrs)
2572 int asidx = cpu_asidx_from_attrs(cpu, attrs);
2573 CPUAddressSpace *cpuas = &cpu->cpu_ases[asidx];
2574 AddressSpaceDispatch *d = qatomic_rcu_read(&cpuas->memory_dispatch);
2575 MemoryRegionSection *sections = d->map.sections;
2577 return &sections[index & ~TARGET_PAGE_MASK];
2580 static void io_mem_init(void)
2582 memory_region_init_io(&io_mem_unassigned, NULL, &unassigned_mem_ops, NULL,
2583 NULL, UINT64_MAX);
2586 AddressSpaceDispatch *address_space_dispatch_new(FlatView *fv)
2588 AddressSpaceDispatch *d = g_new0(AddressSpaceDispatch, 1);
2589 uint16_t n;
2591 n = dummy_section(&d->map, fv, &io_mem_unassigned);
2592 assert(n == PHYS_SECTION_UNASSIGNED);
2594 d->phys_map = (PhysPageEntry) { .ptr = PHYS_MAP_NODE_NIL, .skip = 1 };
2596 return d;
2599 void address_space_dispatch_free(AddressSpaceDispatch *d)
2601 phys_sections_free(&d->map);
2602 g_free(d);
2605 static void do_nothing(CPUState *cpu, run_on_cpu_data d)
2609 static void tcg_log_global_after_sync(MemoryListener *listener)
2611 CPUAddressSpace *cpuas;
2613 /* Wait for the CPU to end the current TB. This avoids the following
2614 * incorrect race:
2616 * vCPU migration
2617 * ---------------------- -------------------------
2618 * TLB check -> slow path
2619 * notdirty_mem_write
2620 * write to RAM
2621 * mark dirty
2622 * clear dirty flag
2623 * TLB check -> fast path
2624 * read memory
2625 * write to RAM
2627 * by pushing the migration thread's memory read after the vCPU thread has
2628 * written the memory.
2630 if (replay_mode == REPLAY_MODE_NONE) {
2632 * VGA can make calls to this function while updating the screen.
2633 * In record/replay mode this causes a deadlock, because
2634 * run_on_cpu waits for rr mutex. Therefore no races are possible
2635 * in this case and no need for making run_on_cpu when
2636 * record/replay is enabled.
2638 cpuas = container_of(listener, CPUAddressSpace, tcg_as_listener);
2639 run_on_cpu(cpuas->cpu, do_nothing, RUN_ON_CPU_NULL);
2643 static void tcg_commit(MemoryListener *listener)
2645 CPUAddressSpace *cpuas;
2646 AddressSpaceDispatch *d;
2648 assert(tcg_enabled());
2649 /* since each CPU stores ram addresses in its TLB cache, we must
2650 reset the modified entries */
2651 cpuas = container_of(listener, CPUAddressSpace, tcg_as_listener);
2652 cpu_reloading_memory_map();
2653 /* The CPU and TLB are protected by the iothread lock.
2654 * We reload the dispatch pointer now because cpu_reloading_memory_map()
2655 * may have split the RCU critical section.
2657 d = address_space_to_dispatch(cpuas->as);
2658 qatomic_rcu_set(&cpuas->memory_dispatch, d);
2659 tlb_flush(cpuas->cpu);
2662 static void memory_map_init(void)
2664 system_memory = g_malloc(sizeof(*system_memory));
2666 memory_region_init(system_memory, NULL, "system", UINT64_MAX);
2667 address_space_init(&address_space_memory, system_memory, "memory");
2669 system_io = g_malloc(sizeof(*system_io));
2670 memory_region_init_io(system_io, NULL, &unassigned_io_ops, NULL, "io",
2671 65536);
2672 address_space_init(&address_space_io, system_io, "I/O");
2675 MemoryRegion *get_system_memory(void)
2677 return system_memory;
2680 MemoryRegion *get_system_io(void)
2682 return system_io;
2685 static void invalidate_and_set_dirty(MemoryRegion *mr, hwaddr addr,
2686 hwaddr length)
2688 uint8_t dirty_log_mask = memory_region_get_dirty_log_mask(mr);
2689 addr += memory_region_get_ram_addr(mr);
2691 /* No early return if dirty_log_mask is or becomes 0, because
2692 * cpu_physical_memory_set_dirty_range will still call
2693 * xen_modified_memory.
2695 if (dirty_log_mask) {
2696 dirty_log_mask =
2697 cpu_physical_memory_range_includes_clean(addr, length, dirty_log_mask);
2699 if (dirty_log_mask & (1 << DIRTY_MEMORY_CODE)) {
2700 assert(tcg_enabled());
2701 tb_invalidate_phys_range(addr, addr + length);
2702 dirty_log_mask &= ~(1 << DIRTY_MEMORY_CODE);
2704 cpu_physical_memory_set_dirty_range(addr, length, dirty_log_mask);
2707 void memory_region_flush_rom_device(MemoryRegion *mr, hwaddr addr, hwaddr size)
2710 * In principle this function would work on other memory region types too,
2711 * but the ROM device use case is the only one where this operation is
2712 * necessary. Other memory regions should use the
2713 * address_space_read/write() APIs.
2715 assert(memory_region_is_romd(mr));
2717 invalidate_and_set_dirty(mr, addr, size);
2720 static int memory_access_size(MemoryRegion *mr, unsigned l, hwaddr addr)
2722 unsigned access_size_max = mr->ops->valid.max_access_size;
2724 /* Regions are assumed to support 1-4 byte accesses unless
2725 otherwise specified. */
2726 if (access_size_max == 0) {
2727 access_size_max = 4;
2730 /* Bound the maximum access by the alignment of the address. */
2731 if (!mr->ops->impl.unaligned) {
2732 unsigned align_size_max = addr & -addr;
2733 if (align_size_max != 0 && align_size_max < access_size_max) {
2734 access_size_max = align_size_max;
2738 /* Don't attempt accesses larger than the maximum. */
2739 if (l > access_size_max) {
2740 l = access_size_max;
2742 l = pow2floor(l);
2744 return l;
2747 static bool prepare_mmio_access(MemoryRegion *mr)
2749 bool release_lock = false;
2751 if (!qemu_mutex_iothread_locked()) {
2752 qemu_mutex_lock_iothread();
2753 release_lock = true;
2755 if (mr->flush_coalesced_mmio) {
2756 qemu_flush_coalesced_mmio_buffer();
2759 return release_lock;
2762 /* Called within RCU critical section. */
2763 static MemTxResult flatview_write_continue(FlatView *fv, hwaddr addr,
2764 MemTxAttrs attrs,
2765 const void *ptr,
2766 hwaddr len, hwaddr addr1,
2767 hwaddr l, MemoryRegion *mr)
2769 uint8_t *ram_ptr;
2770 uint64_t val;
2771 MemTxResult result = MEMTX_OK;
2772 bool release_lock = false;
2773 const uint8_t *buf = ptr;
2775 for (;;) {
2776 if (!memory_access_is_direct(mr, true)) {
2777 release_lock |= prepare_mmio_access(mr);
2778 l = memory_access_size(mr, l, addr1);
2779 /* XXX: could force current_cpu to NULL to avoid
2780 potential bugs */
2781 val = ldn_he_p(buf, l);
2782 result |= memory_region_dispatch_write(mr, addr1, val,
2783 size_memop(l), attrs);
2784 } else {
2785 /* RAM case */
2786 ram_ptr = qemu_ram_ptr_length(mr->ram_block, addr1, &l, false);
2787 memcpy(ram_ptr, buf, l);
2788 invalidate_and_set_dirty(mr, addr1, l);
2791 if (release_lock) {
2792 qemu_mutex_unlock_iothread();
2793 release_lock = false;
2796 len -= l;
2797 buf += l;
2798 addr += l;
2800 if (!len) {
2801 break;
2804 l = len;
2805 mr = flatview_translate(fv, addr, &addr1, &l, true, attrs);
2808 return result;
2811 /* Called from RCU critical section. */
2812 static MemTxResult flatview_write(FlatView *fv, hwaddr addr, MemTxAttrs attrs,
2813 const void *buf, hwaddr len)
2815 hwaddr l;
2816 hwaddr addr1;
2817 MemoryRegion *mr;
2818 MemTxResult result = MEMTX_OK;
2820 l = len;
2821 mr = flatview_translate(fv, addr, &addr1, &l, true, attrs);
2822 result = flatview_write_continue(fv, addr, attrs, buf, len,
2823 addr1, l, mr);
2825 return result;
2828 /* Called within RCU critical section. */
2829 MemTxResult flatview_read_continue(FlatView *fv, hwaddr addr,
2830 MemTxAttrs attrs, void *ptr,
2831 hwaddr len, hwaddr addr1, hwaddr l,
2832 MemoryRegion *mr)
2834 uint8_t *ram_ptr;
2835 uint64_t val;
2836 MemTxResult result = MEMTX_OK;
2837 bool release_lock = false;
2838 uint8_t *buf = ptr;
2840 fuzz_dma_read_cb(addr, len, mr);
2841 for (;;) {
2842 if (!memory_access_is_direct(mr, false)) {
2843 /* I/O case */
2844 release_lock |= prepare_mmio_access(mr);
2845 l = memory_access_size(mr, l, addr1);
2846 result |= memory_region_dispatch_read(mr, addr1, &val,
2847 size_memop(l), attrs);
2848 stn_he_p(buf, l, val);
2849 } else {
2850 /* RAM case */
2851 ram_ptr = qemu_ram_ptr_length(mr->ram_block, addr1, &l, false);
2852 memcpy(buf, ram_ptr, l);
2855 if (release_lock) {
2856 qemu_mutex_unlock_iothread();
2857 release_lock = false;
2860 len -= l;
2861 buf += l;
2862 addr += l;
2864 if (!len) {
2865 break;
2868 l = len;
2869 mr = flatview_translate(fv, addr, &addr1, &l, false, attrs);
2872 return result;
2875 /* Called from RCU critical section. */
2876 static MemTxResult flatview_read(FlatView *fv, hwaddr addr,
2877 MemTxAttrs attrs, void *buf, hwaddr len)
2879 hwaddr l;
2880 hwaddr addr1;
2881 MemoryRegion *mr;
2883 l = len;
2884 mr = flatview_translate(fv, addr, &addr1, &l, false, attrs);
2885 return flatview_read_continue(fv, addr, attrs, buf, len,
2886 addr1, l, mr);
2889 MemTxResult address_space_read_full(AddressSpace *as, hwaddr addr,
2890 MemTxAttrs attrs, void *buf, hwaddr len)
2892 MemTxResult result = MEMTX_OK;
2893 FlatView *fv;
2895 if (len > 0) {
2896 RCU_READ_LOCK_GUARD();
2897 fv = address_space_to_flatview(as);
2898 result = flatview_read(fv, addr, attrs, buf, len);
2901 return result;
2904 MemTxResult address_space_write(AddressSpace *as, hwaddr addr,
2905 MemTxAttrs attrs,
2906 const void *buf, hwaddr len)
2908 MemTxResult result = MEMTX_OK;
2909 FlatView *fv;
2911 if (len > 0) {
2912 RCU_READ_LOCK_GUARD();
2913 fv = address_space_to_flatview(as);
2914 result = flatview_write(fv, addr, attrs, buf, len);
2917 return result;
2920 MemTxResult address_space_rw(AddressSpace *as, hwaddr addr, MemTxAttrs attrs,
2921 void *buf, hwaddr len, bool is_write)
2923 if (is_write) {
2924 return address_space_write(as, addr, attrs, buf, len);
2925 } else {
2926 return address_space_read_full(as, addr, attrs, buf, len);
2930 void cpu_physical_memory_rw(hwaddr addr, void *buf,
2931 hwaddr len, bool is_write)
2933 address_space_rw(&address_space_memory, addr, MEMTXATTRS_UNSPECIFIED,
2934 buf, len, is_write);
2937 enum write_rom_type {
2938 WRITE_DATA,
2939 FLUSH_CACHE,
2942 static inline MemTxResult address_space_write_rom_internal(AddressSpace *as,
2943 hwaddr addr,
2944 MemTxAttrs attrs,
2945 const void *ptr,
2946 hwaddr len,
2947 enum write_rom_type type)
2949 hwaddr l;
2950 uint8_t *ram_ptr;
2951 hwaddr addr1;
2952 MemoryRegion *mr;
2953 const uint8_t *buf = ptr;
2955 RCU_READ_LOCK_GUARD();
2956 while (len > 0) {
2957 l = len;
2958 mr = address_space_translate(as, addr, &addr1, &l, true, attrs);
2960 if (!(memory_region_is_ram(mr) ||
2961 memory_region_is_romd(mr))) {
2962 l = memory_access_size(mr, l, addr1);
2963 } else {
2964 /* ROM/RAM case */
2965 ram_ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
2966 switch (type) {
2967 case WRITE_DATA:
2968 memcpy(ram_ptr, buf, l);
2969 invalidate_and_set_dirty(mr, addr1, l);
2970 break;
2971 case FLUSH_CACHE:
2972 flush_idcache_range((uintptr_t)ram_ptr, (uintptr_t)ram_ptr, l);
2973 break;
2976 len -= l;
2977 buf += l;
2978 addr += l;
2980 return MEMTX_OK;
2983 /* used for ROM loading : can write in RAM and ROM */
2984 MemTxResult address_space_write_rom(AddressSpace *as, hwaddr addr,
2985 MemTxAttrs attrs,
2986 const void *buf, hwaddr len)
2988 return address_space_write_rom_internal(as, addr, attrs,
2989 buf, len, WRITE_DATA);
2992 void cpu_flush_icache_range(hwaddr start, hwaddr len)
2995 * This function should do the same thing as an icache flush that was
2996 * triggered from within the guest. For TCG we are always cache coherent,
2997 * so there is no need to flush anything. For KVM / Xen we need to flush
2998 * the host's instruction cache at least.
3000 if (tcg_enabled()) {
3001 return;
3004 address_space_write_rom_internal(&address_space_memory,
3005 start, MEMTXATTRS_UNSPECIFIED,
3006 NULL, len, FLUSH_CACHE);
3009 typedef struct {
3010 MemoryRegion *mr;
3011 void *buffer;
3012 hwaddr addr;
3013 hwaddr len;
3014 bool in_use;
3015 } BounceBuffer;
3017 static BounceBuffer bounce;
3019 typedef struct MapClient {
3020 QEMUBH *bh;
3021 QLIST_ENTRY(MapClient) link;
3022 } MapClient;
3024 QemuMutex map_client_list_lock;
3025 static QLIST_HEAD(, MapClient) map_client_list
3026 = QLIST_HEAD_INITIALIZER(map_client_list);
3028 static void cpu_unregister_map_client_do(MapClient *client)
3030 QLIST_REMOVE(client, link);
3031 g_free(client);
3034 static void cpu_notify_map_clients_locked(void)
3036 MapClient *client;
3038 while (!QLIST_EMPTY(&map_client_list)) {
3039 client = QLIST_FIRST(&map_client_list);
3040 qemu_bh_schedule(client->bh);
3041 cpu_unregister_map_client_do(client);
3045 void cpu_register_map_client(QEMUBH *bh)
3047 MapClient *client = g_malloc(sizeof(*client));
3049 qemu_mutex_lock(&map_client_list_lock);
3050 client->bh = bh;
3051 QLIST_INSERT_HEAD(&map_client_list, client, link);
3052 if (!qatomic_read(&bounce.in_use)) {
3053 cpu_notify_map_clients_locked();
3055 qemu_mutex_unlock(&map_client_list_lock);
3058 void cpu_exec_init_all(void)
3060 qemu_mutex_init(&ram_list.mutex);
3061 /* The data structures we set up here depend on knowing the page size,
3062 * so no more changes can be made after this point.
3063 * In an ideal world, nothing we did before we had finished the
3064 * machine setup would care about the target page size, and we could
3065 * do this much later, rather than requiring board models to state
3066 * up front what their requirements are.
3068 finalize_target_page_bits();
3069 io_mem_init();
3070 memory_map_init();
3071 qemu_mutex_init(&map_client_list_lock);
3074 void cpu_unregister_map_client(QEMUBH *bh)
3076 MapClient *client;
3078 qemu_mutex_lock(&map_client_list_lock);
3079 QLIST_FOREACH(client, &map_client_list, link) {
3080 if (client->bh == bh) {
3081 cpu_unregister_map_client_do(client);
3082 break;
3085 qemu_mutex_unlock(&map_client_list_lock);
3088 static void cpu_notify_map_clients(void)
3090 qemu_mutex_lock(&map_client_list_lock);
3091 cpu_notify_map_clients_locked();
3092 qemu_mutex_unlock(&map_client_list_lock);
3095 static bool flatview_access_valid(FlatView *fv, hwaddr addr, hwaddr len,
3096 bool is_write, MemTxAttrs attrs)
3098 MemoryRegion *mr;
3099 hwaddr l, xlat;
3101 while (len > 0) {
3102 l = len;
3103 mr = flatview_translate(fv, addr, &xlat, &l, is_write, attrs);
3104 if (!memory_access_is_direct(mr, is_write)) {
3105 l = memory_access_size(mr, l, addr);
3106 if (!memory_region_access_valid(mr, xlat, l, is_write, attrs)) {
3107 return false;
3111 len -= l;
3112 addr += l;
3114 return true;
3117 bool address_space_access_valid(AddressSpace *as, hwaddr addr,
3118 hwaddr len, bool is_write,
3119 MemTxAttrs attrs)
3121 FlatView *fv;
3122 bool result;
3124 RCU_READ_LOCK_GUARD();
3125 fv = address_space_to_flatview(as);
3126 result = flatview_access_valid(fv, addr, len, is_write, attrs);
3127 return result;
3130 static hwaddr
3131 flatview_extend_translation(FlatView *fv, hwaddr addr,
3132 hwaddr target_len,
3133 MemoryRegion *mr, hwaddr base, hwaddr len,
3134 bool is_write, MemTxAttrs attrs)
3136 hwaddr done = 0;
3137 hwaddr xlat;
3138 MemoryRegion *this_mr;
3140 for (;;) {
3141 target_len -= len;
3142 addr += len;
3143 done += len;
3144 if (target_len == 0) {
3145 return done;
3148 len = target_len;
3149 this_mr = flatview_translate(fv, addr, &xlat,
3150 &len, is_write, attrs);
3151 if (this_mr != mr || xlat != base + done) {
3152 return done;
3157 /* Map a physical memory region into a host virtual address.
3158 * May map a subset of the requested range, given by and returned in *plen.
3159 * May return NULL if resources needed to perform the mapping are exhausted.
3160 * Use only for reads OR writes - not for read-modify-write operations.
3161 * Use cpu_register_map_client() to know when retrying the map operation is
3162 * likely to succeed.
3164 void *address_space_map(AddressSpace *as,
3165 hwaddr addr,
3166 hwaddr *plen,
3167 bool is_write,
3168 MemTxAttrs attrs)
3170 hwaddr len = *plen;
3171 hwaddr l, xlat;
3172 MemoryRegion *mr;
3173 void *ptr;
3174 FlatView *fv;
3176 if (len == 0) {
3177 return NULL;
3180 l = len;
3181 RCU_READ_LOCK_GUARD();
3182 fv = address_space_to_flatview(as);
3183 mr = flatview_translate(fv, addr, &xlat, &l, is_write, attrs);
3185 if (!memory_access_is_direct(mr, is_write)) {
3186 if (qatomic_xchg(&bounce.in_use, true)) {
3187 *plen = 0;
3188 return NULL;
3190 /* Avoid unbounded allocations */
3191 l = MIN(l, TARGET_PAGE_SIZE);
3192 bounce.buffer = qemu_memalign(TARGET_PAGE_SIZE, l);
3193 bounce.addr = addr;
3194 bounce.len = l;
3196 memory_region_ref(mr);
3197 bounce.mr = mr;
3198 if (!is_write) {
3199 flatview_read(fv, addr, MEMTXATTRS_UNSPECIFIED,
3200 bounce.buffer, l);
3203 *plen = l;
3204 return bounce.buffer;
3208 memory_region_ref(mr);
3209 *plen = flatview_extend_translation(fv, addr, len, mr, xlat,
3210 l, is_write, attrs);
3211 fuzz_dma_read_cb(addr, *plen, mr);
3212 ptr = qemu_ram_ptr_length(mr->ram_block, xlat, plen, true);
3214 return ptr;
3217 /* Unmaps a memory region previously mapped by address_space_map().
3218 * Will also mark the memory as dirty if is_write is true. access_len gives
3219 * the amount of memory that was actually read or written by the caller.
3221 void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
3222 bool is_write, hwaddr access_len)
3224 if (buffer != bounce.buffer) {
3225 MemoryRegion *mr;
3226 ram_addr_t addr1;
3228 mr = memory_region_from_host(buffer, &addr1);
3229 assert(mr != NULL);
3230 if (is_write) {
3231 invalidate_and_set_dirty(mr, addr1, access_len);
3233 if (xen_enabled()) {
3234 xen_invalidate_map_cache_entry(buffer);
3236 memory_region_unref(mr);
3237 return;
3239 if (is_write) {
3240 address_space_write(as, bounce.addr, MEMTXATTRS_UNSPECIFIED,
3241 bounce.buffer, access_len);
3243 qemu_vfree(bounce.buffer);
3244 bounce.buffer = NULL;
3245 memory_region_unref(bounce.mr);
3246 qatomic_mb_set(&bounce.in_use, false);
3247 cpu_notify_map_clients();
3250 void *cpu_physical_memory_map(hwaddr addr,
3251 hwaddr *plen,
3252 bool is_write)
3254 return address_space_map(&address_space_memory, addr, plen, is_write,
3255 MEMTXATTRS_UNSPECIFIED);
3258 void cpu_physical_memory_unmap(void *buffer, hwaddr len,
3259 bool is_write, hwaddr access_len)
3261 return address_space_unmap(&address_space_memory, buffer, len, is_write, access_len);
3264 #define ARG1_DECL AddressSpace *as
3265 #define ARG1 as
3266 #define SUFFIX
3267 #define TRANSLATE(...) address_space_translate(as, __VA_ARGS__)
3268 #define RCU_READ_LOCK(...) rcu_read_lock()
3269 #define RCU_READ_UNLOCK(...) rcu_read_unlock()
3270 #include "memory_ldst.c.inc"
3272 int64_t address_space_cache_init(MemoryRegionCache *cache,
3273 AddressSpace *as,
3274 hwaddr addr,
3275 hwaddr len,
3276 bool is_write)
3278 AddressSpaceDispatch *d;
3279 hwaddr l;
3280 MemoryRegion *mr;
3281 Int128 diff;
3283 assert(len > 0);
3285 l = len;
3286 cache->fv = address_space_get_flatview(as);
3287 d = flatview_to_dispatch(cache->fv);
3288 cache->mrs = *address_space_translate_internal(d, addr, &cache->xlat, &l, true);
3291 * cache->xlat is now relative to cache->mrs.mr, not to the section itself.
3292 * Take that into account to compute how many bytes are there between
3293 * cache->xlat and the end of the section.
3295 diff = int128_sub(cache->mrs.size,
3296 int128_make64(cache->xlat - cache->mrs.offset_within_region));
3297 l = int128_get64(int128_min(diff, int128_make64(l)));
3299 mr = cache->mrs.mr;
3300 memory_region_ref(mr);
3301 if (memory_access_is_direct(mr, is_write)) {
3302 /* We don't care about the memory attributes here as we're only
3303 * doing this if we found actual RAM, which behaves the same
3304 * regardless of attributes; so UNSPECIFIED is fine.
3306 l = flatview_extend_translation(cache->fv, addr, len, mr,
3307 cache->xlat, l, is_write,
3308 MEMTXATTRS_UNSPECIFIED);
3309 cache->ptr = qemu_ram_ptr_length(mr->ram_block, cache->xlat, &l, true);
3310 } else {
3311 cache->ptr = NULL;
3314 cache->len = l;
3315 cache->is_write = is_write;
3316 return l;
3319 void address_space_cache_invalidate(MemoryRegionCache *cache,
3320 hwaddr addr,
3321 hwaddr access_len)
3323 assert(cache->is_write);
3324 if (likely(cache->ptr)) {
3325 invalidate_and_set_dirty(cache->mrs.mr, addr + cache->xlat, access_len);
3329 void address_space_cache_destroy(MemoryRegionCache *cache)
3331 if (!cache->mrs.mr) {
3332 return;
3335 if (xen_enabled()) {
3336 xen_invalidate_map_cache_entry(cache->ptr);
3338 memory_region_unref(cache->mrs.mr);
3339 flatview_unref(cache->fv);
3340 cache->mrs.mr = NULL;
3341 cache->fv = NULL;
3344 /* Called from RCU critical section. This function has the same
3345 * semantics as address_space_translate, but it only works on a
3346 * predefined range of a MemoryRegion that was mapped with
3347 * address_space_cache_init.
3349 static inline MemoryRegion *address_space_translate_cached(
3350 MemoryRegionCache *cache, hwaddr addr, hwaddr *xlat,
3351 hwaddr *plen, bool is_write, MemTxAttrs attrs)
3353 MemoryRegionSection section;
3354 MemoryRegion *mr;
3355 IOMMUMemoryRegion *iommu_mr;
3356 AddressSpace *target_as;
3358 assert(!cache->ptr);
3359 *xlat = addr + cache->xlat;
3361 mr = cache->mrs.mr;
3362 iommu_mr = memory_region_get_iommu(mr);
3363 if (!iommu_mr) {
3364 /* MMIO region. */
3365 return mr;
3368 section = address_space_translate_iommu(iommu_mr, xlat, plen,
3369 NULL, is_write, true,
3370 &target_as, attrs);
3371 return section.mr;
3374 /* Called from RCU critical section. address_space_read_cached uses this
3375 * out of line function when the target is an MMIO or IOMMU region.
3377 MemTxResult
3378 address_space_read_cached_slow(MemoryRegionCache *cache, hwaddr addr,
3379 void *buf, hwaddr len)
3381 hwaddr addr1, l;
3382 MemoryRegion *mr;
3384 l = len;
3385 mr = address_space_translate_cached(cache, addr, &addr1, &l, false,
3386 MEMTXATTRS_UNSPECIFIED);
3387 return flatview_read_continue(cache->fv,
3388 addr, MEMTXATTRS_UNSPECIFIED, buf, len,
3389 addr1, l, mr);
3392 /* Called from RCU critical section. address_space_write_cached uses this
3393 * out of line function when the target is an MMIO or IOMMU region.
3395 MemTxResult
3396 address_space_write_cached_slow(MemoryRegionCache *cache, hwaddr addr,
3397 const void *buf, hwaddr len)
3399 hwaddr addr1, l;
3400 MemoryRegion *mr;
3402 l = len;
3403 mr = address_space_translate_cached(cache, addr, &addr1, &l, true,
3404 MEMTXATTRS_UNSPECIFIED);
3405 return flatview_write_continue(cache->fv,
3406 addr, MEMTXATTRS_UNSPECIFIED, buf, len,
3407 addr1, l, mr);
3410 #define ARG1_DECL MemoryRegionCache *cache
3411 #define ARG1 cache
3412 #define SUFFIX _cached_slow
3413 #define TRANSLATE(...) address_space_translate_cached(cache, __VA_ARGS__)
3414 #define RCU_READ_LOCK() ((void)0)
3415 #define RCU_READ_UNLOCK() ((void)0)
3416 #include "memory_ldst.c.inc"
3418 /* virtual memory access for debug (includes writing to ROM) */
3419 int cpu_memory_rw_debug(CPUState *cpu, target_ulong addr,
3420 void *ptr, target_ulong len, bool is_write)
3422 hwaddr phys_addr;
3423 target_ulong l, page;
3424 uint8_t *buf = ptr;
3426 cpu_synchronize_state(cpu);
3427 while (len > 0) {
3428 int asidx;
3429 MemTxAttrs attrs;
3430 MemTxResult res;
3432 page = addr & TARGET_PAGE_MASK;
3433 phys_addr = cpu_get_phys_page_attrs_debug(cpu, page, &attrs);
3434 asidx = cpu_asidx_from_attrs(cpu, attrs);
3435 /* if no physical page mapped, return an error */
3436 if (phys_addr == -1)
3437 return -1;
3438 l = (page + TARGET_PAGE_SIZE) - addr;
3439 if (l > len)
3440 l = len;
3441 phys_addr += (addr & ~TARGET_PAGE_MASK);
3442 if (is_write) {
3443 res = address_space_write_rom(cpu->cpu_ases[asidx].as, phys_addr,
3444 attrs, buf, l);
3445 } else {
3446 res = address_space_read(cpu->cpu_ases[asidx].as, phys_addr,
3447 attrs, buf, l);
3449 if (res != MEMTX_OK) {
3450 return -1;
3452 len -= l;
3453 buf += l;
3454 addr += l;
3456 return 0;
3460 * Allows code that needs to deal with migration bitmaps etc to still be built
3461 * target independent.
3463 size_t qemu_target_page_size(void)
3465 return TARGET_PAGE_SIZE;
3468 int qemu_target_page_bits(void)
3470 return TARGET_PAGE_BITS;
3473 int qemu_target_page_bits_min(void)
3475 return TARGET_PAGE_BITS_MIN;
3478 bool cpu_physical_memory_is_io(hwaddr phys_addr)
3480 MemoryRegion*mr;
3481 hwaddr l = 1;
3482 bool res;
3484 RCU_READ_LOCK_GUARD();
3485 mr = address_space_translate(&address_space_memory,
3486 phys_addr, &phys_addr, &l, false,
3487 MEMTXATTRS_UNSPECIFIED);
3489 res = !(memory_region_is_ram(mr) || memory_region_is_romd(mr));
3490 return res;
3493 int qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque)
3495 RAMBlock *block;
3496 int ret = 0;
3498 RCU_READ_LOCK_GUARD();
3499 RAMBLOCK_FOREACH(block) {
3500 ret = func(block, opaque);
3501 if (ret) {
3502 break;
3505 return ret;
3509 * Unmap pages of memory from start to start+length such that
3510 * they a) read as 0, b) Trigger whatever fault mechanism
3511 * the OS provides for postcopy.
3512 * The pages must be unmapped by the end of the function.
3513 * Returns: 0 on success, none-0 on failure
3516 int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length)
3518 int ret = -1;
3520 uint8_t *host_startaddr = rb->host + start;
3522 if (!QEMU_PTR_IS_ALIGNED(host_startaddr, rb->page_size)) {
3523 error_report("ram_block_discard_range: Unaligned start address: %p",
3524 host_startaddr);
3525 goto err;
3528 if ((start + length) <= rb->max_length) {
3529 bool need_madvise, need_fallocate;
3530 if (!QEMU_IS_ALIGNED(length, rb->page_size)) {
3531 error_report("ram_block_discard_range: Unaligned length: %zx",
3532 length);
3533 goto err;
3536 errno = ENOTSUP; /* If we are missing MADVISE etc */
3538 /* The logic here is messy;
3539 * madvise DONTNEED fails for hugepages
3540 * fallocate works on hugepages and shmem
3541 * shared anonymous memory requires madvise REMOVE
3543 need_madvise = (rb->page_size == qemu_host_page_size);
3544 need_fallocate = rb->fd != -1;
3545 if (need_fallocate) {
3546 /* For a file, this causes the area of the file to be zero'd
3547 * if read, and for hugetlbfs also causes it to be unmapped
3548 * so a userfault will trigger.
3550 #ifdef CONFIG_FALLOCATE_PUNCH_HOLE
3551 ret = fallocate(rb->fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
3552 start, length);
3553 if (ret) {
3554 ret = -errno;
3555 error_report("ram_block_discard_range: Failed to fallocate "
3556 "%s:%" PRIx64 " +%zx (%d)",
3557 rb->idstr, start, length, ret);
3558 goto err;
3560 #else
3561 ret = -ENOSYS;
3562 error_report("ram_block_discard_range: fallocate not available/file"
3563 "%s:%" PRIx64 " +%zx (%d)",
3564 rb->idstr, start, length, ret);
3565 goto err;
3566 #endif
3568 if (need_madvise) {
3569 /* For normal RAM this causes it to be unmapped,
3570 * for shared memory it causes the local mapping to disappear
3571 * and to fall back on the file contents (which we just
3572 * fallocate'd away).
3574 #if defined(CONFIG_MADVISE)
3575 if (qemu_ram_is_shared(rb) && rb->fd < 0) {
3576 ret = madvise(host_startaddr, length, QEMU_MADV_REMOVE);
3577 } else {
3578 ret = madvise(host_startaddr, length, QEMU_MADV_DONTNEED);
3580 if (ret) {
3581 ret = -errno;
3582 error_report("ram_block_discard_range: Failed to discard range "
3583 "%s:%" PRIx64 " +%zx (%d)",
3584 rb->idstr, start, length, ret);
3585 goto err;
3587 #else
3588 ret = -ENOSYS;
3589 error_report("ram_block_discard_range: MADVISE not available"
3590 "%s:%" PRIx64 " +%zx (%d)",
3591 rb->idstr, start, length, ret);
3592 goto err;
3593 #endif
3595 trace_ram_block_discard_range(rb->idstr, host_startaddr, length,
3596 need_madvise, need_fallocate, ret);
3597 } else {
3598 error_report("ram_block_discard_range: Overrun block '%s' (%" PRIu64
3599 "/%zx/" RAM_ADDR_FMT")",
3600 rb->idstr, start, length, rb->max_length);
3603 err:
3604 return ret;
3607 bool ramblock_is_pmem(RAMBlock *rb)
3609 return rb->flags & RAM_PMEM;
3612 static void mtree_print_phys_entries(int start, int end, int skip, int ptr)
3614 if (start == end - 1) {
3615 qemu_printf("\t%3d ", start);
3616 } else {
3617 qemu_printf("\t%3d..%-3d ", start, end - 1);
3619 qemu_printf(" skip=%d ", skip);
3620 if (ptr == PHYS_MAP_NODE_NIL) {
3621 qemu_printf(" ptr=NIL");
3622 } else if (!skip) {
3623 qemu_printf(" ptr=#%d", ptr);
3624 } else {
3625 qemu_printf(" ptr=[%d]", ptr);
3627 qemu_printf("\n");
3630 #define MR_SIZE(size) (int128_nz(size) ? (hwaddr)int128_get64( \
3631 int128_sub((size), int128_one())) : 0)
3633 void mtree_print_dispatch(AddressSpaceDispatch *d, MemoryRegion *root)
3635 int i;
3637 qemu_printf(" Dispatch\n");
3638 qemu_printf(" Physical sections\n");
3640 for (i = 0; i < d->map.sections_nb; ++i) {
3641 MemoryRegionSection *s = d->map.sections + i;
3642 const char *names[] = { " [unassigned]", " [not dirty]",
3643 " [ROM]", " [watch]" };
3645 qemu_printf(" #%d @" TARGET_FMT_plx ".." TARGET_FMT_plx
3646 " %s%s%s%s%s",
3648 s->offset_within_address_space,
3649 s->offset_within_address_space + MR_SIZE(s->mr->size),
3650 s->mr->name ? s->mr->name : "(noname)",
3651 i < ARRAY_SIZE(names) ? names[i] : "",
3652 s->mr == root ? " [ROOT]" : "",
3653 s == d->mru_section ? " [MRU]" : "",
3654 s->mr->is_iommu ? " [iommu]" : "");
3656 if (s->mr->alias) {
3657 qemu_printf(" alias=%s", s->mr->alias->name ?
3658 s->mr->alias->name : "noname");
3660 qemu_printf("\n");
3663 qemu_printf(" Nodes (%d bits per level, %d levels) ptr=[%d] skip=%d\n",
3664 P_L2_BITS, P_L2_LEVELS, d->phys_map.ptr, d->phys_map.skip);
3665 for (i = 0; i < d->map.nodes_nb; ++i) {
3666 int j, jprev;
3667 PhysPageEntry prev;
3668 Node *n = d->map.nodes + i;
3670 qemu_printf(" [%d]\n", i);
3672 for (j = 0, jprev = 0, prev = *n[0]; j < ARRAY_SIZE(*n); ++j) {
3673 PhysPageEntry *pe = *n + j;
3675 if (pe->ptr == prev.ptr && pe->skip == prev.skip) {
3676 continue;
3679 mtree_print_phys_entries(jprev, j, prev.skip, prev.ptr);
3681 jprev = j;
3682 prev = *pe;
3685 if (jprev != ARRAY_SIZE(*n)) {
3686 mtree_print_phys_entries(jprev, j, prev.skip, prev.ptr);
3691 /* Require any discards to work. */
3692 static unsigned int ram_block_discard_required_cnt;
3693 /* Require only coordinated discards to work. */
3694 static unsigned int ram_block_coordinated_discard_required_cnt;
3695 /* Disable any discards. */
3696 static unsigned int ram_block_discard_disabled_cnt;
3697 /* Disable only uncoordinated discards. */
3698 static unsigned int ram_block_uncoordinated_discard_disabled_cnt;
3699 static QemuMutex ram_block_discard_disable_mutex;
3701 static void ram_block_discard_disable_mutex_lock(void)
3703 static gsize initialized;
3705 if (g_once_init_enter(&initialized)) {
3706 qemu_mutex_init(&ram_block_discard_disable_mutex);
3707 g_once_init_leave(&initialized, 1);
3709 qemu_mutex_lock(&ram_block_discard_disable_mutex);
3712 static void ram_block_discard_disable_mutex_unlock(void)
3714 qemu_mutex_unlock(&ram_block_discard_disable_mutex);
3717 int ram_block_discard_disable(bool state)
3719 int ret = 0;
3721 ram_block_discard_disable_mutex_lock();
3722 if (!state) {
3723 ram_block_discard_disabled_cnt--;
3724 } else if (ram_block_discard_required_cnt ||
3725 ram_block_coordinated_discard_required_cnt) {
3726 ret = -EBUSY;
3727 } else {
3728 ram_block_discard_disabled_cnt++;
3730 ram_block_discard_disable_mutex_unlock();
3731 return ret;
3734 int ram_block_uncoordinated_discard_disable(bool state)
3736 int ret = 0;
3738 ram_block_discard_disable_mutex_lock();
3739 if (!state) {
3740 ram_block_uncoordinated_discard_disabled_cnt--;
3741 } else if (ram_block_discard_required_cnt) {
3742 ret = -EBUSY;
3743 } else {
3744 ram_block_uncoordinated_discard_disabled_cnt++;
3746 ram_block_discard_disable_mutex_unlock();
3747 return ret;
3750 int ram_block_discard_require(bool state)
3752 int ret = 0;
3754 ram_block_discard_disable_mutex_lock();
3755 if (!state) {
3756 ram_block_discard_required_cnt--;
3757 } else if (ram_block_discard_disabled_cnt ||
3758 ram_block_uncoordinated_discard_disabled_cnt) {
3759 ret = -EBUSY;
3760 } else {
3761 ram_block_discard_required_cnt++;
3763 ram_block_discard_disable_mutex_unlock();
3764 return ret;
3767 int ram_block_coordinated_discard_require(bool state)
3769 int ret = 0;
3771 ram_block_discard_disable_mutex_lock();
3772 if (!state) {
3773 ram_block_coordinated_discard_required_cnt--;
3774 } else if (ram_block_discard_disabled_cnt) {
3775 ret = -EBUSY;
3776 } else {
3777 ram_block_coordinated_discard_required_cnt++;
3779 ram_block_discard_disable_mutex_unlock();
3780 return ret;
3783 bool ram_block_discard_is_disabled(void)
3785 return qatomic_read(&ram_block_discard_disabled_cnt) ||
3786 qatomic_read(&ram_block_uncoordinated_discard_disabled_cnt);
3789 bool ram_block_discard_is_required(void)
3791 return qatomic_read(&ram_block_discard_required_cnt) ||
3792 qatomic_read(&ram_block_coordinated_discard_required_cnt);