/* * QEMU dump * * Copyright Fujitsu, Corp. 2011, 2012 * * Authors: * Wen Congyang * * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. * */ #include "qemu/osdep.h" #include "qemu/cutils.h" #include "elf.h" #include "exec/hwaddr.h" #include "monitor/monitor.h" #include "sysemu/kvm.h" #include "sysemu/dump.h" #include "sysemu/memory_mapping.h" #include "sysemu/runstate.h" #include "sysemu/cpus.h" #include "qapi/error.h" #include "qapi/qapi-commands-dump.h" #include "qapi/qapi-events-dump.h" #include "qapi/qmp/qerror.h" #include "qemu/error-report.h" #include "qemu/main-loop.h" #include "hw/misc/vmcoreinfo.h" #include "migration/blocker.h" #ifdef TARGET_X86_64 #include "win_dump.h" #endif #include #ifdef CONFIG_LZO #include #endif #ifdef CONFIG_SNAPPY #include #endif #ifndef ELF_MACHINE_UNAME #define ELF_MACHINE_UNAME "Unknown" #endif #define MAX_GUEST_NOTE_SIZE (1 << 20) /* 1MB should be enough */ static Error *dump_migration_blocker; #define ELF_NOTE_SIZE(hdr_size, name_size, desc_size) \ ((DIV_ROUND_UP((hdr_size), 4) + \ DIV_ROUND_UP((name_size), 4) + \ DIV_ROUND_UP((desc_size), 4)) * 4) static inline bool dump_is_64bit(DumpState *s) { return s->dump_info.d_class == ELFCLASS64; } static inline bool dump_has_filter(DumpState *s) { return s->filter_area_length > 0; } uint16_t cpu_to_dump16(DumpState *s, uint16_t val) { if (s->dump_info.d_endian == ELFDATA2LSB) { val = cpu_to_le16(val); } else { val = cpu_to_be16(val); } return val; } uint32_t cpu_to_dump32(DumpState *s, uint32_t val) { if (s->dump_info.d_endian == ELFDATA2LSB) { val = cpu_to_le32(val); } else { val = cpu_to_be32(val); } return val; } uint64_t cpu_to_dump64(DumpState *s, uint64_t val) { if (s->dump_info.d_endian == ELFDATA2LSB) { val = cpu_to_le64(val); } else { val = cpu_to_be64(val); } return val; } static int dump_cleanup(DumpState *s) { guest_phys_blocks_free(&s->guest_phys_blocks); memory_mapping_list_free(&s->list); close(s->fd); g_free(s->guest_note); g_array_unref(s->string_table_buf); s->guest_note = NULL; if (s->resume) { if (s->detached) { qemu_mutex_lock_iothread(); } vm_start(); if (s->detached) { qemu_mutex_unlock_iothread(); } } migrate_del_blocker(dump_migration_blocker); return 0; } static int fd_write_vmcore(const void *buf, size_t size, void *opaque) { DumpState *s = opaque; size_t written_size; written_size = qemu_write_full(s->fd, buf, size); if (written_size != size) { return -errno; } return 0; } static void prepare_elf64_header(DumpState *s, Elf64_Ehdr *elf_header) { /* * phnum in the elf header is 16 bit, if we have more segments we * set phnum to PN_XNUM and write the real number of segments to a * special section. */ uint16_t phnum = MIN(s->phdr_num, PN_XNUM); memset(elf_header, 0, sizeof(Elf64_Ehdr)); memcpy(elf_header, ELFMAG, SELFMAG); elf_header->e_ident[EI_CLASS] = ELFCLASS64; elf_header->e_ident[EI_DATA] = s->dump_info.d_endian; elf_header->e_ident[EI_VERSION] = EV_CURRENT; elf_header->e_type = cpu_to_dump16(s, ET_CORE); elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine); elf_header->e_version = cpu_to_dump32(s, EV_CURRENT); elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); elf_header->e_phoff = cpu_to_dump64(s, s->phdr_offset); elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr)); elf_header->e_phnum = cpu_to_dump16(s, phnum); elf_header->e_shoff = cpu_to_dump64(s, s->shdr_offset); elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr)); elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num); elf_header->e_shstrndx = cpu_to_dump16(s, s->shdr_num - 1); } static void prepare_elf32_header(DumpState *s, Elf32_Ehdr *elf_header) { /* * phnum in the elf header is 16 bit, if we have more segments we * set phnum to PN_XNUM and write the real number of segments to a * special section. */ uint16_t phnum = MIN(s->phdr_num, PN_XNUM); memset(elf_header, 0, sizeof(Elf32_Ehdr)); memcpy(elf_header, ELFMAG, SELFMAG); elf_header->e_ident[EI_CLASS] = ELFCLASS32; elf_header->e_ident[EI_DATA] = s->dump_info.d_endian; elf_header->e_ident[EI_VERSION] = EV_CURRENT; elf_header->e_type = cpu_to_dump16(s, ET_CORE); elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine); elf_header->e_version = cpu_to_dump32(s, EV_CURRENT); elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); elf_header->e_phoff = cpu_to_dump32(s, s->phdr_offset); elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr)); elf_header->e_phnum = cpu_to_dump16(s, phnum); elf_header->e_shoff = cpu_to_dump32(s, s->shdr_offset); elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr)); elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num); elf_header->e_shstrndx = cpu_to_dump16(s, s->shdr_num - 1); } static void write_elf_header(DumpState *s, Error **errp) { Elf32_Ehdr elf32_header; Elf64_Ehdr elf64_header; size_t header_size; void *header_ptr; int ret; /* The NULL header and the shstrtab are always defined */ assert(s->shdr_num >= 2); if (dump_is_64bit(s)) { prepare_elf64_header(s, &elf64_header); header_size = sizeof(elf64_header); header_ptr = &elf64_header; } else { prepare_elf32_header(s, &elf32_header); header_size = sizeof(elf32_header); header_ptr = &elf32_header; } ret = fd_write_vmcore(header_ptr, header_size, s); if (ret < 0) { error_setg_errno(errp, -ret, "dump: failed to write elf header"); } } static void write_elf64_load(DumpState *s, MemoryMapping *memory_mapping, int phdr_index, hwaddr offset, hwaddr filesz, Error **errp) { Elf64_Phdr phdr; int ret; memset(&phdr, 0, sizeof(Elf64_Phdr)); phdr.p_type = cpu_to_dump32(s, PT_LOAD); phdr.p_offset = cpu_to_dump64(s, offset); phdr.p_paddr = cpu_to_dump64(s, memory_mapping->phys_addr); phdr.p_filesz = cpu_to_dump64(s, filesz); phdr.p_memsz = cpu_to_dump64(s, memory_mapping->length); phdr.p_vaddr = cpu_to_dump64(s, memory_mapping->virt_addr) ?: phdr.p_paddr; assert(memory_mapping->length >= filesz); ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s); if (ret < 0) { error_setg_errno(errp, -ret, "dump: failed to write program header table"); } } static void write_elf32_load(DumpState *s, MemoryMapping *memory_mapping, int phdr_index, hwaddr offset, hwaddr filesz, Error **errp) { Elf32_Phdr phdr; int ret; memset(&phdr, 0, sizeof(Elf32_Phdr)); phdr.p_type = cpu_to_dump32(s, PT_LOAD); phdr.p_offset = cpu_to_dump32(s, offset); phdr.p_paddr = cpu_to_dump32(s, memory_mapping->phys_addr); phdr.p_filesz = cpu_to_dump32(s, filesz); phdr.p_memsz = cpu_to_dump32(s, memory_mapping->length); phdr.p_vaddr = cpu_to_dump32(s, memory_mapping->virt_addr) ?: phdr.p_paddr; assert(memory_mapping->length >= filesz); ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s); if (ret < 0) { error_setg_errno(errp, -ret, "dump: failed to write program header table"); } } static void prepare_elf64_phdr_note(DumpState *s, Elf64_Phdr *phdr) { memset(phdr, 0, sizeof(*phdr)); phdr->p_type = cpu_to_dump32(s, PT_NOTE); phdr->p_offset = cpu_to_dump64(s, s->note_offset); phdr->p_paddr = 0; phdr->p_filesz = cpu_to_dump64(s, s->note_size); phdr->p_memsz = cpu_to_dump64(s, s->note_size); phdr->p_vaddr = 0; } static inline int cpu_index(CPUState *cpu) { return cpu->cpu_index + 1; } static void write_guest_note(WriteCoreDumpFunction f, DumpState *s, Error **errp) { int ret; if (s->guest_note) { ret = f(s->guest_note, s->guest_note_size, s); if (ret < 0) { error_setg(errp, "dump: failed to write guest note"); } } } static void write_elf64_notes(WriteCoreDumpFunction f, DumpState *s, Error **errp) { CPUState *cpu; int ret; int id; CPU_FOREACH(cpu) { id = cpu_index(cpu); ret = cpu_write_elf64_note(f, cpu, id, s); if (ret < 0) { error_setg(errp, "dump: failed to write elf notes"); return; } } CPU_FOREACH(cpu) { ret = cpu_write_elf64_qemunote(f, cpu, s); if (ret < 0) { error_setg(errp, "dump: failed to write CPU status"); return; } } write_guest_note(f, s, errp); } static void prepare_elf32_phdr_note(DumpState *s, Elf32_Phdr *phdr) { memset(phdr, 0, sizeof(*phdr)); phdr->p_type = cpu_to_dump32(s, PT_NOTE); phdr->p_offset = cpu_to_dump32(s, s->note_offset); phdr->p_paddr = 0; phdr->p_filesz = cpu_to_dump32(s, s->note_size); phdr->p_memsz = cpu_to_dump32(s, s->note_size); phdr->p_vaddr = 0; } static void write_elf32_notes(WriteCoreDumpFunction f, DumpState *s, Error **errp) { CPUState *cpu; int ret; int id; CPU_FOREACH(cpu) { id = cpu_index(cpu); ret = cpu_write_elf32_note(f, cpu, id, s); if (ret < 0) { error_setg(errp, "dump: failed to write elf notes"); return; } } CPU_FOREACH(cpu) { ret = cpu_write_elf32_qemunote(f, cpu, s); if (ret < 0) { error_setg(errp, "dump: failed to write CPU status"); return; } } write_guest_note(f, s, errp); } static void write_elf_phdr_note(DumpState *s, Error **errp) { Elf32_Phdr phdr32; Elf64_Phdr phdr64; void *phdr; size_t size; int ret; if (dump_is_64bit(s)) { prepare_elf64_phdr_note(s, &phdr64); size = sizeof(phdr64); phdr = &phdr64; } else { prepare_elf32_phdr_note(s, &phdr32); size = sizeof(phdr32); phdr = &phdr32; } ret = fd_write_vmcore(phdr, size, s); if (ret < 0) { error_setg_errno(errp, -ret, "dump: failed to write program header table"); } } static void prepare_elf_section_hdr_zero(DumpState *s) { if (dump_is_64bit(s)) { Elf64_Shdr *shdr64 = s->elf_section_hdrs; shdr64->sh_info = cpu_to_dump32(s, s->phdr_num); } else { Elf32_Shdr *shdr32 = s->elf_section_hdrs; shdr32->sh_info = cpu_to_dump32(s, s->phdr_num); } } static void prepare_elf_section_hdr_string(DumpState *s, void *buff) { uint64_t index = s->string_table_buf->len; const char strtab[] = ".shstrtab"; Elf32_Shdr shdr32 = {}; Elf64_Shdr shdr64 = {}; int shdr_size; void *shdr; g_array_append_vals(s->string_table_buf, strtab, sizeof(strtab)); if (dump_is_64bit(s)) { shdr_size = sizeof(Elf64_Shdr); shdr64.sh_type = SHT_STRTAB; shdr64.sh_offset = s->section_offset + s->elf_section_data_size; shdr64.sh_name = index; shdr64.sh_size = s->string_table_buf->len; shdr = &shdr64; } else { shdr_size = sizeof(Elf32_Shdr); shdr32.sh_type = SHT_STRTAB; shdr32.sh_offset = s->section_offset + s->elf_section_data_size; shdr32.sh_name = index; shdr32.sh_size = s->string_table_buf->len; shdr = &shdr32; } memcpy(buff, shdr, shdr_size); } static bool prepare_elf_section_hdrs(DumpState *s, Error **errp) { size_t len, sizeof_shdr; void *buff_hdr; /* * Section ordering: * - HDR zero * - Arch section hdrs * - String table hdr */ sizeof_shdr = dump_is_64bit(s) ? sizeof(Elf64_Shdr) : sizeof(Elf32_Shdr); len = sizeof_shdr * s->shdr_num; s->elf_section_hdrs = g_malloc0(len); buff_hdr = s->elf_section_hdrs; /* * The first section header is ALWAYS a special initial section * header. * * The header should be 0 with one exception being that if * phdr_num is PN_XNUM then the sh_info field contains the real * number of segment entries. * * As we zero allocate the buffer we will only need to modify * sh_info for the PN_XNUM case. */ if (s->phdr_num >= PN_XNUM) { prepare_elf_section_hdr_zero(s); } buff_hdr += sizeof_shdr; /* Add architecture defined section headers */ if (s->dump_info.arch_sections_write_hdr_fn && s->shdr_num > 2) { buff_hdr += s->dump_info.arch_sections_write_hdr_fn(s, buff_hdr); if (s->shdr_num >= SHN_LORESERVE) { error_setg_errno(errp, EINVAL, "dump: too many architecture defined sections"); return false; } } /* * String table is the last section since strings are added via * arch_sections_write_hdr(). */ prepare_elf_section_hdr_string(s, buff_hdr); return true; } static void write_elf_section_headers(DumpState *s, Error **errp) { size_t sizeof_shdr = dump_is_64bit(s) ? sizeof(Elf64_Shdr) : sizeof(Elf32_Shdr); int ret; if (!prepare_elf_section_hdrs(s, errp)) { return; } ret = fd_write_vmcore(s->elf_section_hdrs, s->shdr_num * sizeof_shdr, s); if (ret < 0) { error_setg_errno(errp, -ret, "dump: failed to write section headers"); } g_free(s->elf_section_hdrs); } static void write_elf_sections(DumpState *s, Error **errp) { int ret; if (s->elf_section_data_size) { /* Write architecture section data */ ret = fd_write_vmcore(s->elf_section_data, s->elf_section_data_size, s); if (ret < 0) { error_setg_errno(errp, -ret, "dump: failed to write architecture section data"); return; } } /* Write string table */ ret = fd_write_vmcore(s->string_table_buf->data, s->string_table_buf->len, s); if (ret < 0) { error_setg_errno(errp, -ret, "dump: failed to write string table data"); } } static void write_data(DumpState *s, void *buf, int length, Error **errp) { int ret; ret = fd_write_vmcore(buf, length, s); if (ret < 0) { error_setg_errno(errp, -ret, "dump: failed to save memory"); } else { s->written_size += length; } } /* write the memory to vmcore. 1 page per I/O. */ static void write_memory(DumpState *s, GuestPhysBlock *block, ram_addr_t start, int64_t size, Error **errp) { ERRP_GUARD(); int64_t i; for (i = 0; i < size / s->dump_info.page_size; i++) { write_data(s, block->host_addr + start + i * s->dump_info.page_size, s->dump_info.page_size, errp); if (*errp) { return; } } if ((size % s->dump_info.page_size) != 0) { write_data(s, block->host_addr + start + i * s->dump_info.page_size, size % s->dump_info.page_size, errp); if (*errp) { return; } } } /* get the memory's offset and size in the vmcore */ static void get_offset_range(hwaddr phys_addr, ram_addr_t mapping_length, DumpState *s, hwaddr *p_offset, hwaddr *p_filesz) { GuestPhysBlock *block; hwaddr offset = s->memory_offset; int64_t size_in_block, start; /* When the memory is not stored into vmcore, offset will be -1 */ *p_offset = -1; *p_filesz = 0; if (dump_has_filter(s)) { if (phys_addr < s->filter_area_begin || phys_addr >= s->filter_area_begin + s->filter_area_length) { return; } } QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { if (dump_has_filter(s)) { if (block->target_start >= s->filter_area_begin + s->filter_area_length || block->target_end <= s->filter_area_begin) { /* This block is out of the range */ continue; } if (s->filter_area_begin <= block->target_start) { start = block->target_start; } else { start = s->filter_area_begin; } size_in_block = block->target_end - start; if (s->filter_area_begin + s->filter_area_length < block->target_end) { size_in_block -= block->target_end - (s->filter_area_begin + s->filter_area_length); } } else { start = block->target_start; size_in_block = block->target_end - block->target_start; } if (phys_addr >= start && phys_addr < start + size_in_block) { *p_offset = phys_addr - start + offset; /* The offset range mapped from the vmcore file must not spill over * the GuestPhysBlock, clamp it. The rest of the mapping will be * zero-filled in memory at load time; see * . */ *p_filesz = phys_addr + mapping_length <= start + size_in_block ? mapping_length : size_in_block - (phys_addr - start); return; } offset += size_in_block; } } static void write_elf_phdr_loads(DumpState *s, Error **errp) { ERRP_GUARD(); hwaddr offset, filesz; MemoryMapping *memory_mapping; uint32_t phdr_index = 1; QTAILQ_FOREACH(memory_mapping, &s->list.head, next) { get_offset_range(memory_mapping->phys_addr, memory_mapping->length, s, &offset, &filesz); if (dump_is_64bit(s)) { write_elf64_load(s, memory_mapping, phdr_index++, offset, filesz, errp); } else { write_elf32_load(s, memory_mapping, phdr_index++, offset, filesz, errp); } if (*errp) { return; } if (phdr_index >= s->phdr_num) { break; } } } static void write_elf_notes(DumpState *s, Error **errp) { if (dump_is_64bit(s)) { write_elf64_notes(fd_write_vmcore, s, errp); } else { write_elf32_notes(fd_write_vmcore, s, errp); } } /* write elf header, PT_NOTE and elf note to vmcore. */ static void dump_begin(DumpState *s, Error **errp) { ERRP_GUARD(); /* * the vmcore's format is: * -------------- * | elf header | * -------------- * | sctn_hdr | * -------------- * | PT_NOTE | * -------------- * | PT_LOAD | * -------------- * | ...... | * -------------- * | PT_LOAD | * -------------- * | elf note | * -------------- * | memory | * -------------- * * we only know where the memory is saved after we write elf note into * vmcore. */ /* write elf header to vmcore */ write_elf_header(s, errp); if (*errp) { return; } /* write section headers to vmcore */ write_elf_section_headers(s, errp); if (*errp) { return; } /* write PT_NOTE to vmcore */ write_elf_phdr_note(s, errp); if (*errp) { return; } /* write all PT_LOADs to vmcore */ write_elf_phdr_loads(s, errp); if (*errp) { return; } /* write notes to vmcore */ write_elf_notes(s, errp); } int64_t dump_filtered_memblock_size(GuestPhysBlock *block, int64_t filter_area_start, int64_t filter_area_length) { int64_t size, left, right; /* No filter, return full size */ if (!filter_area_length) { return block->target_end - block->target_start; } /* calculate the overlapped region. */ left = MAX(filter_area_start, block->target_start); right = MIN(filter_area_start + filter_area_length, block->target_end); size = right - left; size = size > 0 ? size : 0; return size; } int64_t dump_filtered_memblock_start(GuestPhysBlock *block, int64_t filter_area_start, int64_t filter_area_length) { if (filter_area_length) { /* return -1 if the block is not within filter area */ if (block->target_start >= filter_area_start + filter_area_length || block->target_end <= filter_area_start) { return -1; } if (filter_area_start > block->target_start) { return filter_area_start - block->target_start; } } return 0; } /* write all memory to vmcore */ static void dump_iterate(DumpState *s, Error **errp) { ERRP_GUARD(); GuestPhysBlock *block; int64_t memblock_size, memblock_start; QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { memblock_start = dump_filtered_memblock_start(block, s->filter_area_begin, s->filter_area_length); if (memblock_start == -1) { continue; } memblock_size = dump_filtered_memblock_size(block, s->filter_area_begin, s->filter_area_length); /* Write the memory to file */ write_memory(s, block, memblock_start, memblock_size, errp); if (*errp) { return; } } } static void dump_end(DumpState *s, Error **errp) { int rc; if (s->elf_section_data_size) { s->elf_section_data = g_malloc0(s->elf_section_data_size); } /* Adds the architecture defined section data to s->elf_section_data */ if (s->dump_info.arch_sections_write_fn && s->elf_section_data_size) { rc = s->dump_info.arch_sections_write_fn(s, s->elf_section_data); if (rc) { error_setg_errno(errp, rc, "dump: failed to get arch section data"); g_free(s->elf_section_data); return; } } /* write sections to vmcore */ write_elf_sections(s, errp); } static void create_vmcore(DumpState *s, Error **errp) { ERRP_GUARD(); dump_begin(s, errp); if (*errp) { return; } /* Iterate over memory and dump it to file */ dump_iterate(s, errp); if (*errp) { return; } /* Write the section data */ dump_end(s, errp); } static int write_start_flat_header(int fd) { MakedumpfileHeader *mh; int ret = 0; QEMU_BUILD_BUG_ON(sizeof *mh > MAX_SIZE_MDF_HEADER); mh = g_malloc0(MAX_SIZE_MDF_HEADER); memcpy(mh->signature, MAKEDUMPFILE_SIGNATURE, MIN(sizeof mh->signature, sizeof MAKEDUMPFILE_SIGNATURE)); mh->type = cpu_to_be64(TYPE_FLAT_HEADER); mh->version = cpu_to_be64(VERSION_FLAT_HEADER); size_t written_size; written_size = qemu_write_full(fd, mh, MAX_SIZE_MDF_HEADER); if (written_size != MAX_SIZE_MDF_HEADER) { ret = -1; } g_free(mh); return ret; } static int write_end_flat_header(int fd) { MakedumpfileDataHeader mdh; mdh.offset = END_FLAG_FLAT_HEADER; mdh.buf_size = END_FLAG_FLAT_HEADER; size_t written_size; written_size = qemu_write_full(fd, &mdh, sizeof(mdh)); if (written_size != sizeof(mdh)) { return -1; } return 0; } static int write_buffer(int fd, off_t offset, const void *buf, size_t size) { size_t written_size; MakedumpfileDataHeader mdh; mdh.offset = cpu_to_be64(offset); mdh.buf_size = cpu_to_be64(size); written_size = qemu_write_full(fd, &mdh, sizeof(mdh)); if (written_size != sizeof(mdh)) { return -1; } written_size = qemu_write_full(fd, buf, size); if (written_size != size) { return -1; } return 0; } static int buf_write_note(const void *buf, size_t size, void *opaque) { DumpState *s = opaque; /* note_buf is not enough */ if (s->note_buf_offset + size > s->note_size) { return -1; } memcpy(s->note_buf + s->note_buf_offset, buf, size); s->note_buf_offset += size; return 0; } /* * This function retrieves various sizes from an elf header. * * @note has to be a valid ELF note. The return sizes are unmodified * (not padded or rounded up to be multiple of 4). */ static void get_note_sizes(DumpState *s, const void *note, uint64_t *note_head_size, uint64_t *name_size, uint64_t *desc_size) { uint64_t note_head_sz; uint64_t name_sz; uint64_t desc_sz; if (dump_is_64bit(s)) { const Elf64_Nhdr *hdr = note; note_head_sz = sizeof(Elf64_Nhdr); name_sz = tswap64(hdr->n_namesz); desc_sz = tswap64(hdr->n_descsz); } else { const Elf32_Nhdr *hdr = note; note_head_sz = sizeof(Elf32_Nhdr); name_sz = tswap32(hdr->n_namesz); desc_sz = tswap32(hdr->n_descsz); } if (note_head_size) { *note_head_size = note_head_sz; } if (name_size) { *name_size = name_sz; } if (desc_size) { *desc_size = desc_sz; } } static bool note_name_equal(DumpState *s, const uint8_t *note, const char *name) { int len = strlen(name) + 1; uint64_t head_size, name_size; get_note_sizes(s, note, &head_size, &name_size, NULL); head_size = ROUND_UP(head_size, 4); return name_size == len && memcmp(note + head_size, name, len) == 0; } /* write common header, sub header and elf note to vmcore */ static void create_header32(DumpState *s, Error **errp) { ERRP_GUARD(); DiskDumpHeader32 *dh = NULL; KdumpSubHeader32 *kh = NULL; size_t size; uint32_t block_size; uint32_t sub_hdr_size; uint32_t bitmap_blocks; uint32_t status = 0; uint64_t offset_note; /* write common header, the version of kdump-compressed format is 6th */ size = sizeof(DiskDumpHeader32); dh = g_malloc0(size); memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN); dh->header_version = cpu_to_dump32(s, 6); block_size = s->dump_info.page_size; dh->block_size = cpu_to_dump32(s, block_size); sub_hdr_size = sizeof(struct KdumpSubHeader32) + s->note_size; sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size); dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size); /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */ dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX)); dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus); bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2; dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks); strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine)); if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) { status |= DUMP_DH_COMPRESSED_ZLIB; } #ifdef CONFIG_LZO if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) { status |= DUMP_DH_COMPRESSED_LZO; } #endif #ifdef CONFIG_SNAPPY if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) { status |= DUMP_DH_COMPRESSED_SNAPPY; } #endif dh->status = cpu_to_dump32(s, status); if (write_buffer(s->fd, 0, dh, size) < 0) { error_setg(errp, "dump: failed to write disk dump header"); goto out; } /* write sub header */ size = sizeof(KdumpSubHeader32); kh = g_malloc0(size); /* 64bit max_mapnr_64 */ kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr); kh->phys_base = cpu_to_dump32(s, s->dump_info.phys_base); kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL); offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size; if (s->guest_note && note_name_equal(s, s->guest_note, "VMCOREINFO")) { uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo; get_note_sizes(s, s->guest_note, &hsize, &name_size, &size_vmcoreinfo_desc); offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size + (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4; kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo); kh->size_vmcoreinfo = cpu_to_dump32(s, size_vmcoreinfo_desc); } kh->offset_note = cpu_to_dump64(s, offset_note); kh->note_size = cpu_to_dump32(s, s->note_size); if (write_buffer(s->fd, DISKDUMP_HEADER_BLOCKS * block_size, kh, size) < 0) { error_setg(errp, "dump: failed to write kdump sub header"); goto out; } /* write note */ s->note_buf = g_malloc0(s->note_size); s->note_buf_offset = 0; /* use s->note_buf to store notes temporarily */ write_elf32_notes(buf_write_note, s, errp); if (*errp) { goto out; } if (write_buffer(s->fd, offset_note, s->note_buf, s->note_size) < 0) { error_setg(errp, "dump: failed to write notes"); goto out; } /* get offset of dump_bitmap */ s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) * block_size; /* get offset of page */ s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) * block_size; out: g_free(dh); g_free(kh); g_free(s->note_buf); } /* write common header, sub header and elf note to vmcore */ static void create_header64(DumpState *s, Error **errp) { ERRP_GUARD(); DiskDumpHeader64 *dh = NULL; KdumpSubHeader64 *kh = NULL; size_t size; uint32_t block_size; uint32_t sub_hdr_size; uint32_t bitmap_blocks; uint32_t status = 0; uint64_t offset_note; /* write common header, the version of kdump-compressed format is 6th */ size = sizeof(DiskDumpHeader64); dh = g_malloc0(size); memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN); dh->header_version = cpu_to_dump32(s, 6); block_size = s->dump_info.page_size; dh->block_size = cpu_to_dump32(s, block_size); sub_hdr_size = sizeof(struct KdumpSubHeader64) + s->note_size; sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size); dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size); /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */ dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX)); dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus); bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2; dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks); strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine)); if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) { status |= DUMP_DH_COMPRESSED_ZLIB; } #ifdef CONFIG_LZO if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) { status |= DUMP_DH_COMPRESSED_LZO; } #endif #ifdef CONFIG_SNAPPY if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) { status |= DUMP_DH_COMPRESSED_SNAPPY; } #endif dh->status = cpu_to_dump32(s, status); if (write_buffer(s->fd, 0, dh, size) < 0) { error_setg(errp, "dump: failed to write disk dump header"); goto out; } /* write sub header */ size = sizeof(KdumpSubHeader64); kh = g_malloc0(size); /* 64bit max_mapnr_64 */ kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr); kh->phys_base = cpu_to_dump64(s, s->dump_info.phys_base); kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL); offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size; if (s->guest_note && note_name_equal(s, s->guest_note, "VMCOREINFO")) { uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo; get_note_sizes(s, s->guest_note, &hsize, &name_size, &size_vmcoreinfo_desc); offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size + (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4; kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo); kh->size_vmcoreinfo = cpu_to_dump64(s, size_vmcoreinfo_desc); } kh->offset_note = cpu_to_dump64(s, offset_note); kh->note_size = cpu_to_dump64(s, s->note_size); if (write_buffer(s->fd, DISKDUMP_HEADER_BLOCKS * block_size, kh, size) < 0) { error_setg(errp, "dump: failed to write kdump sub header"); goto out; } /* write note */ s->note_buf = g_malloc0(s->note_size); s->note_buf_offset = 0; /* use s->note_buf to store notes temporarily */ write_elf64_notes(buf_write_note, s, errp); if (*errp) { goto out; } if (write_buffer(s->fd, offset_note, s->note_buf, s->note_size) < 0) { error_setg(errp, "dump: failed to write notes"); goto out; } /* get offset of dump_bitmap */ s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) * block_size; /* get offset of page */ s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) * block_size; out: g_free(dh); g_free(kh); g_free(s->note_buf); } static void write_dump_header(DumpState *s, Error **errp) { if (dump_is_64bit(s)) { create_header64(s, errp); } else { create_header32(s, errp); } } static size_t dump_bitmap_get_bufsize(DumpState *s) { return s->dump_info.page_size; } /* * set dump_bitmap sequencely. the bit before last_pfn is not allowed to be * rewritten, so if need to set the first bit, set last_pfn and pfn to 0. * set_dump_bitmap will always leave the recently set bit un-sync. And setting * (last bit + sizeof(buf) * 8) to 0 will do flushing the content in buf into * vmcore, ie. synchronizing un-sync bit into vmcore. */ static int set_dump_bitmap(uint64_t last_pfn, uint64_t pfn, bool value, uint8_t *buf, DumpState *s) { off_t old_offset, new_offset; off_t offset_bitmap1, offset_bitmap2; uint32_t byte, bit; size_t bitmap_bufsize = dump_bitmap_get_bufsize(s); size_t bits_per_buf = bitmap_bufsize * CHAR_BIT; /* should not set the previous place */ assert(last_pfn <= pfn); /* * if the bit needed to be set is not cached in buf, flush the data in buf * to vmcore firstly. * making new_offset be bigger than old_offset can also sync remained data * into vmcore. */ old_offset = bitmap_bufsize * (last_pfn / bits_per_buf); new_offset = bitmap_bufsize * (pfn / bits_per_buf); while (old_offset < new_offset) { /* calculate the offset and write dump_bitmap */ offset_bitmap1 = s->offset_dump_bitmap + old_offset; if (write_buffer(s->fd, offset_bitmap1, buf, bitmap_bufsize) < 0) { return -1; } /* dump level 1 is chosen, so 1st and 2nd bitmap are same */ offset_bitmap2 = s->offset_dump_bitmap + s->len_dump_bitmap + old_offset; if (write_buffer(s->fd, offset_bitmap2, buf, bitmap_bufsize) < 0) { return -1; } memset(buf, 0, bitmap_bufsize); old_offset += bitmap_bufsize; } /* get the exact place of the bit in the buf, and set it */ byte = (pfn % bits_per_buf) / CHAR_BIT; bit = (pfn % bits_per_buf) % CHAR_BIT; if (value) { buf[byte] |= 1u << bit; } else { buf[byte] &= ~(1u << bit); } return 0; } static uint64_t dump_paddr_to_pfn(DumpState *s, uint64_t addr) { int target_page_shift = ctz32(s->dump_info.page_size); return (addr >> target_page_shift) - ARCH_PFN_OFFSET; } static uint64_t dump_pfn_to_paddr(DumpState *s, uint64_t pfn) { int target_page_shift = ctz32(s->dump_info.page_size); return (pfn + ARCH_PFN_OFFSET) << target_page_shift; } /* * Return the page frame number and the page content in *bufptr. bufptr can be * NULL. If not NULL, *bufptr must contains a target page size of pre-allocated * memory. This is not necessarily the memory returned. */ static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr, uint8_t **bufptr, DumpState *s) { GuestPhysBlock *block = *blockptr; uint32_t page_size = s->dump_info.page_size; uint8_t *buf = NULL, *hbuf; hwaddr addr; /* block == NULL means the start of the iteration */ if (!block) { block = QTAILQ_FIRST(&s->guest_phys_blocks.head); *blockptr = block; addr = block->target_start; *pfnptr = dump_paddr_to_pfn(s, addr); } else { *pfnptr += 1; addr = dump_pfn_to_paddr(s, *pfnptr); } assert(block != NULL); while (1) { if (addr >= block->target_start && addr < block->target_end) { size_t n = MIN(block->target_end - addr, page_size - addr % page_size); hbuf = block->host_addr + (addr - block->target_start); if (!buf) { if (n == page_size) { /* this is a whole target page, go for it */ assert(addr % page_size == 0); buf = hbuf; break; } else if (bufptr) { assert(*bufptr); buf = *bufptr; memset(buf, 0, page_size); } else { return true; } } memcpy(buf + addr % page_size, hbuf, n); addr += n; if (addr % page_size == 0) { /* we filled up the page */ break; } } else { /* the next page is in the next block */ *blockptr = block = QTAILQ_NEXT(block, next); if (!block) { break; } addr = block->target_start; /* are we still in the same page? */ if (dump_paddr_to_pfn(s, addr) != *pfnptr) { if (buf) { /* no, but we already filled something earlier, return it */ break; } else { /* else continue from there */ *pfnptr = dump_paddr_to_pfn(s, addr); } } } } if (bufptr) { *bufptr = buf; } return buf != NULL; } static void write_dump_bitmap(DumpState *s, Error **errp) { int ret = 0; uint64_t last_pfn, pfn; void *dump_bitmap_buf; size_t num_dumpable; GuestPhysBlock *block_iter = NULL; size_t bitmap_bufsize = dump_bitmap_get_bufsize(s); size_t bits_per_buf = bitmap_bufsize * CHAR_BIT; /* dump_bitmap_buf is used to store dump_bitmap temporarily */ dump_bitmap_buf = g_malloc0(bitmap_bufsize); num_dumpable = 0; last_pfn = 0; /* * exam memory page by page, and set the bit in dump_bitmap corresponded * to the existing page. */ while (get_next_page(&block_iter, &pfn, NULL, s)) { ret = set_dump_bitmap(last_pfn, pfn, true, dump_bitmap_buf, s); if (ret < 0) { error_setg(errp, "dump: failed to set dump_bitmap"); goto out; } last_pfn = pfn; num_dumpable++; } /* * set_dump_bitmap will always leave the recently set bit un-sync. Here we * set the remaining bits from last_pfn to the end of the bitmap buffer to * 0. With those set, the un-sync bit will be synchronized into the vmcore. */ if (num_dumpable > 0) { ret = set_dump_bitmap(last_pfn, last_pfn + bits_per_buf, false, dump_bitmap_buf, s); if (ret < 0) { error_setg(errp, "dump: failed to sync dump_bitmap"); goto out; } } /* number of dumpable pages that will be dumped later */ s->num_dumpable = num_dumpable; out: g_free(dump_bitmap_buf); } static void prepare_data_cache(DataCache *data_cache, DumpState *s, off_t offset) { data_cache->fd = s->fd; data_cache->data_size = 0; data_cache->buf_size = 4 * dump_bitmap_get_bufsize(s); data_cache->buf = g_malloc0(data_cache->buf_size); data_cache->offset = offset; } static int write_cache(DataCache *dc, const void *buf, size_t size, bool flag_sync) { /* * dc->buf_size should not be less than size, otherwise dc will never be * enough */ assert(size <= dc->buf_size); /* * if flag_sync is set, synchronize data in dc->buf into vmcore. * otherwise check if the space is enough for caching data in buf, if not, * write the data in dc->buf to dc->fd and reset dc->buf */ if ((!flag_sync && dc->data_size + size > dc->buf_size) || (flag_sync && dc->data_size > 0)) { if (write_buffer(dc->fd, dc->offset, dc->buf, dc->data_size) < 0) { return -1; } dc->offset += dc->data_size; dc->data_size = 0; } if (!flag_sync) { memcpy(dc->buf + dc->data_size, buf, size); dc->data_size += size; } return 0; } static void free_data_cache(DataCache *data_cache) { g_free(data_cache->buf); } static size_t get_len_buf_out(size_t page_size, uint32_t flag_compress) { switch (flag_compress) { case DUMP_DH_COMPRESSED_ZLIB: return compressBound(page_size); case DUMP_DH_COMPRESSED_LZO: /* * LZO will expand incompressible data by a little amount. Please check * the following URL to see the expansion calculation: * http://www.oberhumer.com/opensource/lzo/lzofaq.php */ return page_size + page_size / 16 + 64 + 3; #ifdef CONFIG_SNAPPY case DUMP_DH_COMPRESSED_SNAPPY: return snappy_max_compressed_length(page_size); #endif } return 0; } static void write_dump_pages(DumpState *s, Error **errp) { int ret = 0; DataCache page_desc, page_data; size_t len_buf_out, size_out; #ifdef CONFIG_LZO lzo_bytep wrkmem = NULL; #endif uint8_t *buf_out = NULL; off_t offset_desc, offset_data; PageDescriptor pd, pd_zero; uint8_t *buf; GuestPhysBlock *block_iter = NULL; uint64_t pfn_iter; g_autofree uint8_t *page = NULL; /* get offset of page_desc and page_data in dump file */ offset_desc = s->offset_page; offset_data = offset_desc + sizeof(PageDescriptor) * s->num_dumpable; prepare_data_cache(&page_desc, s, offset_desc); prepare_data_cache(&page_data, s, offset_data); /* prepare buffer to store compressed data */ len_buf_out = get_len_buf_out(s->dump_info.page_size, s->flag_compress); assert(len_buf_out != 0); #ifdef CONFIG_LZO wrkmem = g_malloc(LZO1X_1_MEM_COMPRESS); #endif buf_out = g_malloc(len_buf_out); /* * init zero page's page_desc and page_data, because every zero page * uses the same page_data */ pd_zero.size = cpu_to_dump32(s, s->dump_info.page_size); pd_zero.flags = cpu_to_dump32(s, 0); pd_zero.offset = cpu_to_dump64(s, offset_data); pd_zero.page_flags = cpu_to_dump64(s, 0); buf = g_malloc0(s->dump_info.page_size); ret = write_cache(&page_data, buf, s->dump_info.page_size, false); g_free(buf); if (ret < 0) { error_setg(errp, "dump: failed to write page data (zero page)"); goto out; } offset_data += s->dump_info.page_size; page = g_malloc(s->dump_info.page_size); /* * dump memory to vmcore page by page. zero page will all be resided in the * first page of page section */ for (buf = page; get_next_page(&block_iter, &pfn_iter, &buf, s); buf = page) { /* check zero page */ if (buffer_is_zero(buf, s->dump_info.page_size)) { ret = write_cache(&page_desc, &pd_zero, sizeof(PageDescriptor), false); if (ret < 0) { error_setg(errp, "dump: failed to write page desc"); goto out; } } else { /* * not zero page, then: * 1. compress the page * 2. write the compressed page into the cache of page_data * 3. get page desc of the compressed page and write it into the * cache of page_desc * * only one compression format will be used here, for * s->flag_compress is set. But when compression fails to work, * we fall back to save in plaintext. */ size_out = len_buf_out; if ((s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) && (compress2(buf_out, (uLongf *)&size_out, buf, s->dump_info.page_size, Z_BEST_SPEED) == Z_OK) && (size_out < s->dump_info.page_size)) { pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_ZLIB); pd.size = cpu_to_dump32(s, size_out); ret = write_cache(&page_data, buf_out, size_out, false); if (ret < 0) { error_setg(errp, "dump: failed to write page data"); goto out; } #ifdef CONFIG_LZO } else if ((s->flag_compress & DUMP_DH_COMPRESSED_LZO) && (lzo1x_1_compress(buf, s->dump_info.page_size, buf_out, (lzo_uint *)&size_out, wrkmem) == LZO_E_OK) && (size_out < s->dump_info.page_size)) { pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_LZO); pd.size = cpu_to_dump32(s, size_out); ret = write_cache(&page_data, buf_out, size_out, false); if (ret < 0) { error_setg(errp, "dump: failed to write page data"); goto out; } #endif #ifdef CONFIG_SNAPPY } else if ((s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) && (snappy_compress((char *)buf, s->dump_info.page_size, (char *)buf_out, &size_out) == SNAPPY_OK) && (size_out < s->dump_info.page_size)) { pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_SNAPPY); pd.size = cpu_to_dump32(s, size_out); ret = write_cache(&page_data, buf_out, size_out, false); if (ret < 0) { error_setg(errp, "dump: failed to write page data"); goto out; } #endif } else { /* * fall back to save in plaintext, size_out should be * assigned the target's page size */ pd.flags = cpu_to_dump32(s, 0); size_out = s->dump_info.page_size; pd.size = cpu_to_dump32(s, size_out); ret = write_cache(&page_data, buf, s->dump_info.page_size, false); if (ret < 0) { error_setg(errp, "dump: failed to write page data"); goto out; } } /* get and write page desc here */ pd.page_flags = cpu_to_dump64(s, 0); pd.offset = cpu_to_dump64(s, offset_data); offset_data += size_out; ret = write_cache(&page_desc, &pd, sizeof(PageDescriptor), false); if (ret < 0) { error_setg(errp, "dump: failed to write page desc"); goto out; } } s->written_size += s->dump_info.page_size; } ret = write_cache(&page_desc, NULL, 0, true); if (ret < 0) { error_setg(errp, "dump: failed to sync cache for page_desc"); goto out; } ret = write_cache(&page_data, NULL, 0, true); if (ret < 0) { error_setg(errp, "dump: failed to sync cache for page_data"); goto out; } out: free_data_cache(&page_desc); free_data_cache(&page_data); #ifdef CONFIG_LZO g_free(wrkmem); #endif g_free(buf_out); } static void create_kdump_vmcore(DumpState *s, Error **errp) { ERRP_GUARD(); int ret; /* * the kdump-compressed format is: * File offset * +------------------------------------------+ 0x0 * | main header (struct disk_dump_header) | * |------------------------------------------+ block 1 * | sub header (struct kdump_sub_header) | * |------------------------------------------+ block 2 * | 1st-dump_bitmap | * |------------------------------------------+ block 2 + X blocks * | 2nd-dump_bitmap | (aligned by block) * |------------------------------------------+ block 2 + 2 * X blocks * | page desc for pfn 0 (struct page_desc) | (aligned by block) * | page desc for pfn 1 (struct page_desc) | * | : | * |------------------------------------------| (not aligned by block) * | page data (pfn 0) | * | page data (pfn 1) | * | : | * +------------------------------------------+ */ ret = write_start_flat_header(s->fd); if (ret < 0) { error_setg(errp, "dump: failed to write start flat header"); return; } write_dump_header(s, errp); if (*errp) { return; } write_dump_bitmap(s, errp); if (*errp) { return; } write_dump_pages(s, errp); if (*errp) { return; } ret = write_end_flat_header(s->fd); if (ret < 0) { error_setg(errp, "dump: failed to write end flat header"); return; } } static int validate_start_block(DumpState *s) { GuestPhysBlock *block; if (!dump_has_filter(s)) { return 0; } QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { /* This block is out of the range */ if (block->target_start >= s->filter_area_begin + s->filter_area_length || block->target_end <= s->filter_area_begin) { continue; } return 0; } return -1; } static void get_max_mapnr(DumpState *s) { GuestPhysBlock *last_block; last_block = QTAILQ_LAST(&s->guest_phys_blocks.head); s->max_mapnr = dump_paddr_to_pfn(s, last_block->target_end); } static DumpState dump_state_global = { .status = DUMP_STATUS_NONE }; static void dump_state_prepare(DumpState *s) { /* zero the struct, setting status to active */ *s = (DumpState) { .status = DUMP_STATUS_ACTIVE }; } bool qemu_system_dump_in_progress(void) { DumpState *state = &dump_state_global; return (qatomic_read(&state->status) == DUMP_STATUS_ACTIVE); } /* * calculate total size of memory to be dumped (taking filter into * account.) */ static int64_t dump_calculate_size(DumpState *s) { GuestPhysBlock *block; int64_t total = 0; QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { total += dump_filtered_memblock_size(block, s->filter_area_begin, s->filter_area_length); } return total; } static void vmcoreinfo_update_phys_base(DumpState *s) { uint64_t size, note_head_size, name_size, phys_base; char **lines; uint8_t *vmci; size_t i; if (!note_name_equal(s, s->guest_note, "VMCOREINFO")) { return; } get_note_sizes(s, s->guest_note, ¬e_head_size, &name_size, &size); note_head_size = ROUND_UP(note_head_size, 4); vmci = s->guest_note + note_head_size + ROUND_UP(name_size, 4); *(vmci + size) = '\0'; lines = g_strsplit((char *)vmci, "\n", -1); for (i = 0; lines[i]; i++) { const char *prefix = NULL; if (s->dump_info.d_machine == EM_X86_64) { prefix = "NUMBER(phys_base)="; } else if (s->dump_info.d_machine == EM_AARCH64) { prefix = "NUMBER(PHYS_OFFSET)="; } if (prefix && g_str_has_prefix(lines[i], prefix)) { if (qemu_strtou64(lines[i] + strlen(prefix), NULL, 16, &phys_base) < 0) { warn_report("Failed to read %s", prefix); } else { s->dump_info.phys_base = phys_base; } break; } } g_strfreev(lines); } static void dump_init(DumpState *s, int fd, bool has_format, DumpGuestMemoryFormat format, bool paging, bool has_filter, int64_t begin, int64_t length, Error **errp) { ERRP_GUARD(); VMCoreInfoState *vmci = vmcoreinfo_find(); CPUState *cpu; int nr_cpus; int ret; s->has_format = has_format; s->format = format; s->written_size = 0; /* kdump-compressed is conflict with paging and filter */ if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { assert(!paging && !has_filter); } if (runstate_is_running()) { vm_stop(RUN_STATE_SAVE_VM); s->resume = true; } else { s->resume = false; } /* If we use KVM, we should synchronize the registers before we get dump * info or physmap info. */ cpu_synchronize_all_states(); nr_cpus = 0; CPU_FOREACH(cpu) { nr_cpus++; } s->fd = fd; if (has_filter && !length) { error_setg(errp, QERR_INVALID_PARAMETER, "length"); goto cleanup; } s->filter_area_begin = begin; s->filter_area_length = length; /* First index is 0, it's the special null name */ s->string_table_buf = g_array_new(FALSE, TRUE, 1); /* * Allocate the null name, due to the clearing option set to true * it will be 0. */ g_array_set_size(s->string_table_buf, 1); memory_mapping_list_init(&s->list); guest_phys_blocks_init(&s->guest_phys_blocks); guest_phys_blocks_append(&s->guest_phys_blocks); s->total_size = dump_calculate_size(s); #ifdef DEBUG_DUMP_GUEST_MEMORY fprintf(stderr, "DUMP: total memory to dump: %lu\n", s->total_size); #endif /* it does not make sense to dump non-existent memory */ if (!s->total_size) { error_setg(errp, "dump: no guest memory to dump"); goto cleanup; } /* Is the filter filtering everything? */ if (validate_start_block(s) == -1) { error_setg(errp, QERR_INVALID_PARAMETER, "begin"); goto cleanup; } /* get dump info: endian, class and architecture. * If the target architecture is not supported, cpu_get_dump_info() will * return -1. */ ret = cpu_get_dump_info(&s->dump_info, &s->guest_phys_blocks); if (ret < 0) { error_setg(errp, "dumping guest memory is not supported on this target"); goto cleanup; } if (!s->dump_info.page_size) { s->dump_info.page_size = TARGET_PAGE_SIZE; } s->note_size = cpu_get_note_size(s->dump_info.d_class, s->dump_info.d_machine, nr_cpus); assert(s->note_size >= 0); /* * The goal of this block is to (a) update the previously guessed * phys_base, (b) copy the guest note out of the guest. * Failure to do so is not fatal for dumping. */ if (vmci) { uint64_t addr, note_head_size, name_size, desc_size; uint32_t size; uint16_t format; note_head_size = dump_is_64bit(s) ? sizeof(Elf64_Nhdr) : sizeof(Elf32_Nhdr); format = le16_to_cpu(vmci->vmcoreinfo.guest_format); size = le32_to_cpu(vmci->vmcoreinfo.size); addr = le64_to_cpu(vmci->vmcoreinfo.paddr); if (!vmci->has_vmcoreinfo) { warn_report("guest note is not present"); } else if (size < note_head_size || size > MAX_GUEST_NOTE_SIZE) { warn_report("guest note size is invalid: %" PRIu32, size); } else if (format != FW_CFG_VMCOREINFO_FORMAT_ELF) { warn_report("guest note format is unsupported: %" PRIu16, format); } else { s->guest_note = g_malloc(size + 1); /* +1 for adding \0 */ cpu_physical_memory_read(addr, s->guest_note, size); get_note_sizes(s, s->guest_note, NULL, &name_size, &desc_size); s->guest_note_size = ELF_NOTE_SIZE(note_head_size, name_size, desc_size); if (name_size > MAX_GUEST_NOTE_SIZE || desc_size > MAX_GUEST_NOTE_SIZE || s->guest_note_size > size) { warn_report("Invalid guest note header"); g_free(s->guest_note); s->guest_note = NULL; } else { vmcoreinfo_update_phys_base(s); s->note_size += s->guest_note_size; } } } /* get memory mapping */ if (paging) { qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, errp); if (*errp) { goto cleanup; } } else { qemu_get_guest_simple_memory_mapping(&s->list, &s->guest_phys_blocks); } s->nr_cpus = nr_cpus; get_max_mapnr(s); uint64_t tmp; tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), s->dump_info.page_size); s->len_dump_bitmap = tmp * s->dump_info.page_size; /* init for kdump-compressed format */ if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { switch (format) { case DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB: s->flag_compress = DUMP_DH_COMPRESSED_ZLIB; break; case DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO: #ifdef CONFIG_LZO if (lzo_init() != LZO_E_OK) { error_setg(errp, "failed to initialize the LZO library"); goto cleanup; } #endif s->flag_compress = DUMP_DH_COMPRESSED_LZO; break; case DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY: s->flag_compress = DUMP_DH_COMPRESSED_SNAPPY; break; default: s->flag_compress = 0; } return; } if (dump_has_filter(s)) { memory_mapping_filter(&s->list, s->filter_area_begin, s->filter_area_length); } /* * The first section header is always a special one in which most * fields are 0. The section header string table is also always * set. */ s->shdr_num = 2; /* * Adds the number of architecture sections to shdr_num and sets * elf_section_data_size so we know the offsets and sizes of all * parts. */ if (s->dump_info.arch_sections_add_fn) { s->dump_info.arch_sections_add_fn(s); } /* * calculate shdr_num so we know the offsets and sizes of all * parts. * Calculate phdr_num * * The absolute maximum amount of phdrs is UINT32_MAX - 1 as * sh_info is 32 bit. There's special handling once we go over * UINT16_MAX - 1 but that is handled in the ehdr and section * code. */ s->phdr_num = 1; /* Reserve PT_NOTE */ if (s->list.num <= UINT32_MAX - 1) { s->phdr_num += s->list.num; } else { s->phdr_num = UINT32_MAX; } /* * Now that the number of section and program headers is known we * can calculate the offsets of the headers and data. */ if (dump_is_64bit(s)) { s->shdr_offset = sizeof(Elf64_Ehdr); s->phdr_offset = s->shdr_offset + sizeof(Elf64_Shdr) * s->shdr_num; s->note_offset = s->phdr_offset + sizeof(Elf64_Phdr) * s->phdr_num; } else { s->shdr_offset = sizeof(Elf32_Ehdr); s->phdr_offset = s->shdr_offset + sizeof(Elf32_Shdr) * s->shdr_num; s->note_offset = s->phdr_offset + sizeof(Elf32_Phdr) * s->phdr_num; } s->memory_offset = s->note_offset + s->note_size; s->section_offset = s->memory_offset + s->total_size; return; cleanup: dump_cleanup(s); } /* this operation might be time consuming. */ static void dump_process(DumpState *s, Error **errp) { ERRP_GUARD(); DumpQueryResult *result = NULL; if (s->has_format && s->format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) { #ifdef TARGET_X86_64 create_win_dump(s, errp); #endif } else if (s->has_format && s->format != DUMP_GUEST_MEMORY_FORMAT_ELF) { create_kdump_vmcore(s, errp); } else { create_vmcore(s, errp); } /* make sure status is written after written_size updates */ smp_wmb(); qatomic_set(&s->status, (*errp ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED)); /* send DUMP_COMPLETED message (unconditionally) */ result = qmp_query_dump(NULL); /* should never fail */ assert(result); qapi_event_send_dump_completed(result, *errp ? error_get_pretty(*errp) : NULL); qapi_free_DumpQueryResult(result); dump_cleanup(s); } static void *dump_thread(void *data) { DumpState *s = (DumpState *)data; dump_process(s, NULL); return NULL; } DumpQueryResult *qmp_query_dump(Error **errp) { DumpQueryResult *result = g_new(DumpQueryResult, 1); DumpState *state = &dump_state_global; result->status = qatomic_read(&state->status); /* make sure we are reading status and written_size in order */ smp_rmb(); result->completed = state->written_size; result->total = state->total_size; return result; } void qmp_dump_guest_memory(bool paging, const char *file, bool has_detach, bool detach, bool has_begin, int64_t begin, bool has_length, int64_t length, bool has_format, DumpGuestMemoryFormat format, Error **errp) { ERRP_GUARD(); const char *p; int fd = -1; DumpState *s; bool detach_p = false; if (runstate_check(RUN_STATE_INMIGRATE)) { error_setg(errp, "Dump not allowed during incoming migration."); return; } /* if there is a dump in background, we should wait until the dump * finished */ if (qemu_system_dump_in_progress()) { error_setg(errp, "There is a dump in process, please wait."); return; } /* * kdump-compressed format need the whole memory dumped, so paging or * filter is not supported here. */ if ((has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) && (paging || has_begin || has_length)) { error_setg(errp, "kdump-compressed format doesn't support paging or " "filter"); return; } if (has_begin && !has_length) { error_setg(errp, QERR_MISSING_PARAMETER, "length"); return; } if (!has_begin && has_length) { error_setg(errp, QERR_MISSING_PARAMETER, "begin"); return; } if (has_detach) { detach_p = detach; } /* check whether lzo/snappy is supported */ #ifndef CONFIG_LZO if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO) { error_setg(errp, "kdump-lzo is not available now"); return; } #endif #ifndef CONFIG_SNAPPY if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY) { error_setg(errp, "kdump-snappy is not available now"); return; } #endif #ifndef TARGET_X86_64 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) { error_setg(errp, "Windows dump is only available for x86-64"); return; } #endif #if !defined(WIN32) if (strstart(file, "fd:", &p)) { fd = monitor_get_fd(monitor_cur(), p, errp); if (fd == -1) { return; } } #endif if (strstart(file, "file:", &p)) { fd = qemu_open_old(p, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR); if (fd < 0) { error_setg_file_open(errp, errno, p); return; } } if (fd == -1) { error_setg(errp, QERR_INVALID_PARAMETER, "protocol"); return; } if (!dump_migration_blocker) { error_setg(&dump_migration_blocker, "Live migration disabled: dump-guest-memory in progress"); } /* * Allows even for -only-migratable, but forbid migration during the * process of dump guest memory. */ if (migrate_add_blocker_internal(dump_migration_blocker, errp)) { /* Remember to release the fd before passing it over to dump state */ close(fd); return; } s = &dump_state_global; dump_state_prepare(s); dump_init(s, fd, has_format, format, paging, has_begin, begin, length, errp); if (*errp) { qatomic_set(&s->status, DUMP_STATUS_FAILED); return; } if (detach_p) { /* detached dump */ s->detached = true; qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread, s, QEMU_THREAD_DETACHED); } else { /* sync dump */ dump_process(s, errp); } } DumpGuestMemoryCapability *qmp_query_dump_guest_memory_capability(Error **errp) { DumpGuestMemoryCapability *cap = g_new0(DumpGuestMemoryCapability, 1); DumpGuestMemoryFormatList **tail = &cap->formats; /* elf is always available */ QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_ELF); /* kdump-zlib is always available */ QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB); /* add new item if kdump-lzo is available */ #ifdef CONFIG_LZO QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO); #endif /* add new item if kdump-snappy is available */ #ifdef CONFIG_SNAPPY QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY); #endif /* Windows dump is available only if target is x86_64 */ #ifdef TARGET_X86_64 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_WIN_DMP); #endif return cap; }