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