/* * 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-common.h" #include "elf.h" #include "cpu.h" #include "exec/cpu-all.h" #include "exec/hwaddr.h" #include "monitor/monitor.h" #include "sysemu/kvm.h" #include "sysemu/dump.h" #include "sysemu/sysemu.h" #include "sysemu/memory_mapping.h" #include "sysemu/cpus.h" #include "qapi/qmp/qerror.h" #include "qmp-commands.h" #include #ifdef CONFIG_LZO #include #endif #ifdef CONFIG_SNAPPY #include #endif #ifndef ELF_MACHINE_UNAME #define ELF_MACHINE_UNAME "Unknown" #endif 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); if (s->resume) { vm_start(); } 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 -1; } return 0; } static void write_elf64_header(DumpState *s, Error **errp) { Elf64_Ehdr elf_header; int ret; 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, sizeof(Elf64_Ehdr)); elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr)); elf_header.e_phnum = cpu_to_dump16(s, s->phdr_num); if (s->have_section) { uint64_t shoff = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) * s->sh_info; elf_header.e_shoff = cpu_to_dump64(s, shoff); elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr)); elf_header.e_shnum = cpu_to_dump16(s, 1); } ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s); if (ret < 0) { error_setg(errp, "dump: failed to write elf header"); } } static void write_elf32_header(DumpState *s, Error **errp) { Elf32_Ehdr elf_header; int ret; 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, sizeof(Elf32_Ehdr)); elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr)); elf_header.e_phnum = cpu_to_dump16(s, s->phdr_num); if (s->have_section) { uint32_t shoff = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) * s->sh_info; elf_header.e_shoff = cpu_to_dump32(s, shoff); elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr)); elf_header.e_shnum = cpu_to_dump16(s, 1); } ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s); if (ret < 0) { error_setg(errp, "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); assert(memory_mapping->length >= filesz); ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s); if (ret < 0) { error_setg(errp, "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); assert(memory_mapping->length >= filesz); ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s); if (ret < 0) { error_setg(errp, "dump: failed to write program header table"); } } static void write_elf64_note(DumpState *s, Error **errp) { Elf64_Phdr phdr; hwaddr begin = s->memory_offset - s->note_size; int ret; memset(&phdr, 0, sizeof(Elf64_Phdr)); phdr.p_type = cpu_to_dump32(s, PT_NOTE); phdr.p_offset = cpu_to_dump64(s, begin); 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; ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s); if (ret < 0) { error_setg(errp, "dump: failed to write program header table"); } } static inline int cpu_index(CPUState *cpu) { return cpu->cpu_index + 1; } 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; } } } static void write_elf32_note(DumpState *s, Error **errp) { hwaddr begin = s->memory_offset - s->note_size; Elf32_Phdr phdr; int ret; memset(&phdr, 0, sizeof(Elf32_Phdr)); phdr.p_type = cpu_to_dump32(s, PT_NOTE); phdr.p_offset = cpu_to_dump32(s, begin); 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; ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s); if (ret < 0) { error_setg(errp, "dump: failed to write program header table"); } } 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; } } } static void write_elf_section(DumpState *s, int type, Error **errp) { Elf32_Shdr shdr32; Elf64_Shdr shdr64; int shdr_size; void *shdr; int ret; if (type == 0) { shdr_size = sizeof(Elf32_Shdr); memset(&shdr32, 0, shdr_size); shdr32.sh_info = cpu_to_dump32(s, s->sh_info); shdr = &shdr32; } else { shdr_size = sizeof(Elf64_Shdr); memset(&shdr64, 0, shdr_size); shdr64.sh_info = cpu_to_dump32(s, s->sh_info); shdr = &shdr64; } ret = fd_write_vmcore(&shdr, shdr_size, s); if (ret < 0) { error_setg(errp, "dump: failed to write section header table"); } } 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(errp, "dump: failed to save memory"); } } /* 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) { int64_t i; Error *local_err = NULL; 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, &local_err); if (local_err) { error_propagate(errp, local_err); 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, &local_err); if (local_err) { error_propagate(errp, local_err); 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 (s->has_filter) { if (phys_addr < s->begin || phys_addr >= s->begin + s->length) { return; } } QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { if (s->has_filter) { if (block->target_start >= s->begin + s->length || block->target_end <= s->begin) { /* This block is out of the range */ continue; } if (s->begin <= block->target_start) { start = block->target_start; } else { start = s->begin; } size_in_block = block->target_end - start; if (s->begin + s->length < block->target_end) { size_in_block -= block->target_end - (s->begin + s->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_loads(DumpState *s, Error **errp) { hwaddr offset, filesz; MemoryMapping *memory_mapping; uint32_t phdr_index = 1; uint32_t max_index; Error *local_err = NULL; if (s->have_section) { max_index = s->sh_info; } else { max_index = s->phdr_num; } QTAILQ_FOREACH(memory_mapping, &s->list.head, next) { get_offset_range(memory_mapping->phys_addr, memory_mapping->length, s, &offset, &filesz); if (s->dump_info.d_class == ELFCLASS64) { write_elf64_load(s, memory_mapping, phdr_index++, offset, filesz, &local_err); } else { write_elf32_load(s, memory_mapping, phdr_index++, offset, filesz, &local_err); } if (local_err) { error_propagate(errp, local_err); return; } if (phdr_index >= max_index) { break; } } } /* write elf header, PT_NOTE and elf note to vmcore. */ static void dump_begin(DumpState *s, Error **errp) { Error *local_err = NULL; /* * the vmcore's format is: * -------------- * | elf header | * -------------- * | PT_NOTE | * -------------- * | PT_LOAD | * -------------- * | ...... | * -------------- * | PT_LOAD | * -------------- * | sec_hdr | * -------------- * | elf note | * -------------- * | memory | * -------------- * * we only know where the memory is saved after we write elf note into * vmcore. */ /* write elf header to vmcore */ if (s->dump_info.d_class == ELFCLASS64) { write_elf64_header(s, &local_err); } else { write_elf32_header(s, &local_err); } if (local_err) { error_propagate(errp, local_err); return; } if (s->dump_info.d_class == ELFCLASS64) { /* write PT_NOTE to vmcore */ write_elf64_note(s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } /* write all PT_LOAD to vmcore */ write_elf_loads(s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } /* write section to vmcore */ if (s->have_section) { write_elf_section(s, 1, &local_err); if (local_err) { error_propagate(errp, local_err); return; } } /* write notes to vmcore */ write_elf64_notes(fd_write_vmcore, s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } } else { /* write PT_NOTE to vmcore */ write_elf32_note(s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } /* write all PT_LOAD to vmcore */ write_elf_loads(s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } /* write section to vmcore */ if (s->have_section) { write_elf_section(s, 0, &local_err); if (local_err) { error_propagate(errp, local_err); return; } } /* write notes to vmcore */ write_elf32_notes(fd_write_vmcore, s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } } } static int get_next_block(DumpState *s, GuestPhysBlock *block) { while (1) { block = QTAILQ_NEXT(block, next); if (!block) { /* no more block */ return 1; } s->start = 0; s->next_block = block; if (s->has_filter) { if (block->target_start >= s->begin + s->length || block->target_end <= s->begin) { /* This block is out of the range */ continue; } if (s->begin > block->target_start) { s->start = s->begin - block->target_start; } } return 0; } } /* write all memory to vmcore */ static void dump_iterate(DumpState *s, Error **errp) { GuestPhysBlock *block; int64_t size; Error *local_err = NULL; do { block = s->next_block; size = block->target_end - block->target_start; if (s->has_filter) { size -= s->start; if (s->begin + s->length < block->target_end) { size -= block->target_end - (s->begin + s->length); } } write_memory(s, block, s->start, size, &local_err); if (local_err) { error_propagate(errp, local_err); return; } } while (!get_next_block(s, block)); } static void create_vmcore(DumpState *s, Error **errp) { Error *local_err = NULL; dump_begin(s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } dump_iterate(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; } /* write common header, sub header and elf note to vmcore */ static void create_header32(DumpState *s, Error **errp) { 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; Error *local_err = NULL; /* write common header, the version of kdump-compressed format is 6th */ size = sizeof(DiskDumpHeader32); dh = g_malloc0(size); strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE)); 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; 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, &local_err); if (local_err) { error_propagate(errp, local_err); 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) { 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; Error *local_err = NULL; /* write common header, the version of kdump-compressed format is 6th */ size = sizeof(DiskDumpHeader64); dh = g_malloc0(size); strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE)); 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; 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, &local_err); if (local_err) { error_propagate(errp, local_err); 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) { Error *local_err = NULL; if (s->dump_info.d_class == ELFCLASS32) { create_header32(s, &local_err); } else { create_header64(s, &local_err); } if (local_err) { error_propagate(errp, local_err); } } 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; } /* * exam every page and return the page frame number and the address of the page. * bufptr can be NULL. note: the blocks here is supposed to reflect guest-phys * blocks, so block->target_start and block->target_end should be interal * multiples of the target page size. */ static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr, uint8_t **bufptr, DumpState *s) { GuestPhysBlock *block = *blockptr; hwaddr addr, target_page_mask = ~((hwaddr)s->dump_info.page_size - 1); uint8_t *buf; /* block == NULL means the start of the iteration */ if (!block) { block = QTAILQ_FIRST(&s->guest_phys_blocks.head); *blockptr = block; assert((block->target_start & ~target_page_mask) == 0); assert((block->target_end & ~target_page_mask) == 0); *pfnptr = dump_paddr_to_pfn(s, block->target_start); if (bufptr) { *bufptr = block->host_addr; } return true; } *pfnptr = *pfnptr + 1; addr = dump_pfn_to_paddr(s, *pfnptr); if ((addr >= block->target_start) && (addr + s->dump_info.page_size <= block->target_end)) { buf = block->host_addr + (addr - block->target_start); } else { /* the next page is in the next block */ block = QTAILQ_NEXT(block, next); *blockptr = block; if (!block) { return false; } assert((block->target_start & ~target_page_mask) == 0); assert((block->target_end & ~target_page_mask) == 0); *pfnptr = dump_paddr_to_pfn(s, block->target_start); buf = block->host_addr; } if (bufptr) { *bufptr = buf; } return true; } 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; } /* * check if the page is all 0 */ static inline bool is_zero_page(const uint8_t *buf, size_t page_size) { return buffer_is_zero(buf, page_size); } 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; /* 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; /* * dump memory to vmcore page by page. zero page will all be resided in the * first page of page section */ while (get_next_page(&block_iter, &pfn_iter, &buf, s)) { /* check zero page */ if (is_zero_page(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; } } } 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) { int ret; Error *local_err = NULL; /* * 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, &local_err); if (local_err) { error_propagate(errp, local_err); return; } write_dump_bitmap(s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } write_dump_pages(s, &local_err); if (local_err) { error_propagate(errp, local_err); return; } ret = write_end_flat_header(s->fd); if (ret < 0) { error_setg(errp, "dump: failed to write end flat header"); return; } } static ram_addr_t get_start_block(DumpState *s) { GuestPhysBlock *block; if (!s->has_filter) { s->next_block = QTAILQ_FIRST(&s->guest_phys_blocks.head); return 0; } QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { if (block->target_start >= s->begin + s->length || block->target_end <= s->begin) { /* This block is out of the range */ continue; } s->next_block = block; if (s->begin > block->target_start) { s->start = s->begin - block->target_start; } else { s->start = 0; } return s->start; } return -1; } static void get_max_mapnr(DumpState *s) { GuestPhysBlock *last_block; last_block = QTAILQ_LAST(&s->guest_phys_blocks.head, GuestPhysBlockHead); 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 dump_in_progress(void) { DumpState *state = &dump_state_global; return (state->status == DUMP_STATUS_ACTIVE); } 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) { CPUState *cpu; int nr_cpus; Error *err = NULL; int ret; s->has_format = has_format; s->format = format; /* 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; s->has_filter = has_filter; s->begin = begin; s->length = length; memory_mapping_list_init(&s->list); guest_phys_blocks_init(&s->guest_phys_blocks); guest_phys_blocks_append(&s->guest_phys_blocks); s->start = get_start_block(s); if (s->start == -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, QERR_UNSUPPORTED); 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); if (s->note_size < 0) { error_setg(errp, QERR_UNSUPPORTED); goto cleanup; } /* get memory mapping */ if (paging) { qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, &err); if (err != NULL) { error_propagate(errp, err); 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 (s->has_filter) { memory_mapping_filter(&s->list, s->begin, s->length); } /* * calculate phdr_num * * the type of ehdr->e_phnum is uint16_t, so we should avoid overflow */ s->phdr_num = 1; /* PT_NOTE */ if (s->list.num < UINT16_MAX - 2) { s->phdr_num += s->list.num; s->have_section = false; } else { s->have_section = true; s->phdr_num = PN_XNUM; s->sh_info = 1; /* PT_NOTE */ /* the type of shdr->sh_info is uint32_t, so we should avoid overflow */ if (s->list.num <= UINT32_MAX - 1) { s->sh_info += s->list.num; } else { s->sh_info = UINT32_MAX; } } if (s->dump_info.d_class == ELFCLASS64) { if (s->have_section) { s->memory_offset = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) * s->sh_info + sizeof(Elf64_Shdr) + s->note_size; } else { s->memory_offset = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) * s->phdr_num + s->note_size; } } else { if (s->have_section) { s->memory_offset = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) * s->sh_info + sizeof(Elf32_Shdr) + s->note_size; } else { s->memory_offset = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) * s->phdr_num + s->note_size; } } return; cleanup: dump_cleanup(s); } /* this operation might be time consuming. */ static void dump_process(DumpState *s, Error **errp) { Error *local_err = NULL; if (s->has_format && s->format != DUMP_GUEST_MEMORY_FORMAT_ELF) { create_kdump_vmcore(s, &local_err); } else { create_vmcore(s, &local_err); } s->status = (local_err ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED); error_propagate(errp, local_err); dump_cleanup(s); } static void *dump_thread(void *data) { Error *err = NULL; DumpState *s = (DumpState *)data; dump_process(s, &err); if (err) { /* TODO: notify user the error */ error_free(err); } return NULL; } 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) { const char *p; int fd = -1; DumpState *s; Error *local_err = NULL; 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 (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 #if !defined(WIN32) if (strstart(file, "fd:", &p)) { fd = monitor_get_fd(cur_mon, p, errp); if (fd == -1) { return; } } #endif if (strstart(file, "file:", &p)) { fd = qemu_open(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; } s = &dump_state_global; dump_state_prepare(s); dump_init(s, fd, has_format, format, paging, has_begin, begin, length, &local_err); if (local_err) { error_propagate(errp, local_err); s->status = DUMP_STATUS_FAILED; return; } if (detach_p) { /* detached dump */ 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) { DumpGuestMemoryFormatList *item; DumpGuestMemoryCapability *cap = g_malloc0(sizeof(DumpGuestMemoryCapability)); /* elf is always available */ item = g_malloc0(sizeof(DumpGuestMemoryFormatList)); cap->formats = item; item->value = DUMP_GUEST_MEMORY_FORMAT_ELF; /* kdump-zlib is always available */ item->next = g_malloc0(sizeof(DumpGuestMemoryFormatList)); item = item->next; item->value = DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB; /* add new item if kdump-lzo is available */ #ifdef CONFIG_LZO item->next = g_malloc0(sizeof(DumpGuestMemoryFormatList)); item = item->next; item->value = DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO; #endif /* add new item if kdump-snappy is available */ #ifdef CONFIG_SNAPPY item->next = g_malloc0(sizeof(DumpGuestMemoryFormatList)); item = item->next; item->value = DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY; #endif return cap; }