From 783e9b4826b95e53e33c42db6b4bd7d89bdff147 Mon Sep 17 00:00:00 2001 From: Wen Congyang Date: Mon, 7 May 2012 12:10:47 +0800 Subject: introduce a new monitor command 'dump-guest-memory' to dump guest's memory The command's usage: dump-guest-memory [-p] protocol [begin] [length] The supported protocol can be file or fd: 1. file: the protocol starts with "file:", and the following string is the file's path. 2. fd: the protocol starts with "fd:", and the following string is the fd's name. Note: 1. If you want to use gdb to process the core, please specify -p option. The reason why the -p option is not default is: a. guest machine in a catastrophic state can have corrupted memory, which we cannot trust. b. The guest machine can be in read-mode even if paging is enabled. For example: the guest machine uses ACPI to sleep, and ACPI sleep state goes in real-mode. 2. If you don't want to dump all guest's memory, please specify the start physical address and the length. Signed-off-by: Wen Congyang Signed-off-by: Luiz Capitulino --- dump.c | 883 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 883 insertions(+) create mode 100644 dump.c (limited to 'dump.c') diff --git a/dump.c b/dump.c new file mode 100644 index 0000000000..0ca14f87ed --- /dev/null +++ b/dump.c @@ -0,0 +1,883 @@ +/* + * QEMU dump + * + * Copyright Fujitsu, Corp. 2011, 2012 + * + * Authors: + * Wen Congyang + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ + +#include "qemu-common.h" +#include +#include "elf.h" +#include +#include +#include "cpu.h" +#include "cpu-all.h" +#include "targphys.h" +#include "monitor.h" +#include "kvm.h" +#include "dump.h" +#include "sysemu.h" +#include "bswap.h" +#include "memory_mapping.h" +#include "error.h" +#include "qmp-commands.h" +#include "gdbstub.h" + +#if defined(CONFIG_HAVE_CORE_DUMP) +static uint16_t cpu_convert_to_target16(uint16_t val, int endian) +{ + if (endian == ELFDATA2LSB) { + val = cpu_to_le16(val); + } else { + val = cpu_to_be16(val); + } + + return val; +} + +static uint32_t cpu_convert_to_target32(uint32_t val, int endian) +{ + if (endian == ELFDATA2LSB) { + val = cpu_to_le32(val); + } else { + val = cpu_to_be32(val); + } + + return val; +} + +static uint64_t cpu_convert_to_target64(uint64_t val, int endian) +{ + if (endian == ELFDATA2LSB) { + val = cpu_to_le64(val); + } else { + val = cpu_to_be64(val); + } + + return val; +} + +typedef struct DumpState { + ArchDumpInfo dump_info; + MemoryMappingList list; + uint16_t phdr_num; + uint32_t sh_info; + bool have_section; + bool resume; + size_t note_size; + target_phys_addr_t memory_offset; + int fd; + + RAMBlock *block; + ram_addr_t start; + bool has_filter; + int64_t begin; + int64_t length; + Error **errp; +} DumpState; + +static int dump_cleanup(DumpState *s) +{ + int ret = 0; + + memory_mapping_list_free(&s->list); + if (s->fd != -1) { + close(s->fd); + } + if (s->resume) { + vm_start(); + } + + return ret; +} + +static void dump_error(DumpState *s, const char *reason) +{ + dump_cleanup(s); +} + +static int fd_write_vmcore(void *buf, size_t size, void *opaque) +{ + DumpState *s = opaque; + int fd = s->fd; + size_t writen_size; + + /* The fd may be passed from user, and it can be non-blocked */ + while (size) { + writen_size = qemu_write_full(fd, buf, size); + if (writen_size != size && errno != EAGAIN) { + return -1; + } + + buf += writen_size; + size -= writen_size; + } + + return 0; +} + +static int write_elf64_header(DumpState *s) +{ + Elf64_Ehdr elf_header; + int ret; + int endian = s->dump_info.d_endian; + + 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_convert_to_target16(ET_CORE, endian); + elf_header.e_machine = cpu_convert_to_target16(s->dump_info.d_machine, + endian); + elf_header.e_version = cpu_convert_to_target32(EV_CURRENT, endian); + elf_header.e_ehsize = cpu_convert_to_target16(sizeof(elf_header), endian); + elf_header.e_phoff = cpu_convert_to_target64(sizeof(Elf64_Ehdr), endian); + elf_header.e_phentsize = cpu_convert_to_target16(sizeof(Elf64_Phdr), + endian); + elf_header.e_phnum = cpu_convert_to_target16(s->phdr_num, endian); + if (s->have_section) { + uint64_t shoff = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) * s->sh_info; + + elf_header.e_shoff = cpu_convert_to_target64(shoff, endian); + elf_header.e_shentsize = cpu_convert_to_target16(sizeof(Elf64_Shdr), + endian); + elf_header.e_shnum = cpu_convert_to_target16(1, endian); + } + + ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s); + if (ret < 0) { + dump_error(s, "dump: failed to write elf header.\n"); + return -1; + } + + return 0; +} + +static int write_elf32_header(DumpState *s) +{ + Elf32_Ehdr elf_header; + int ret; + int endian = s->dump_info.d_endian; + + 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] = endian; + elf_header.e_ident[EI_VERSION] = EV_CURRENT; + elf_header.e_type = cpu_convert_to_target16(ET_CORE, endian); + elf_header.e_machine = cpu_convert_to_target16(s->dump_info.d_machine, + endian); + elf_header.e_version = cpu_convert_to_target32(EV_CURRENT, endian); + elf_header.e_ehsize = cpu_convert_to_target16(sizeof(elf_header), endian); + elf_header.e_phoff = cpu_convert_to_target32(sizeof(Elf32_Ehdr), endian); + elf_header.e_phentsize = cpu_convert_to_target16(sizeof(Elf32_Phdr), + endian); + elf_header.e_phnum = cpu_convert_to_target16(s->phdr_num, endian); + if (s->have_section) { + uint32_t shoff = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) * s->sh_info; + + elf_header.e_shoff = cpu_convert_to_target32(shoff, endian); + elf_header.e_shentsize = cpu_convert_to_target16(sizeof(Elf32_Shdr), + endian); + elf_header.e_shnum = cpu_convert_to_target16(1, endian); + } + + ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s); + if (ret < 0) { + dump_error(s, "dump: failed to write elf header.\n"); + return -1; + } + + return 0; +} + +static int write_elf64_load(DumpState *s, MemoryMapping *memory_mapping, + int phdr_index, target_phys_addr_t offset) +{ + Elf64_Phdr phdr; + int ret; + int endian = s->dump_info.d_endian; + + memset(&phdr, 0, sizeof(Elf64_Phdr)); + phdr.p_type = cpu_convert_to_target32(PT_LOAD, endian); + phdr.p_offset = cpu_convert_to_target64(offset, endian); + phdr.p_paddr = cpu_convert_to_target64(memory_mapping->phys_addr, endian); + if (offset == -1) { + /* When the memory is not stored into vmcore, offset will be -1 */ + phdr.p_filesz = 0; + } else { + phdr.p_filesz = cpu_convert_to_target64(memory_mapping->length, endian); + } + phdr.p_memsz = cpu_convert_to_target64(memory_mapping->length, endian); + phdr.p_vaddr = cpu_convert_to_target64(memory_mapping->virt_addr, endian); + + ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s); + if (ret < 0) { + dump_error(s, "dump: failed to write program header table.\n"); + return -1; + } + + return 0; +} + +static int write_elf32_load(DumpState *s, MemoryMapping *memory_mapping, + int phdr_index, target_phys_addr_t offset) +{ + Elf32_Phdr phdr; + int ret; + int endian = s->dump_info.d_endian; + + memset(&phdr, 0, sizeof(Elf32_Phdr)); + phdr.p_type = cpu_convert_to_target32(PT_LOAD, endian); + phdr.p_offset = cpu_convert_to_target32(offset, endian); + phdr.p_paddr = cpu_convert_to_target32(memory_mapping->phys_addr, endian); + if (offset == -1) { + /* When the memory is not stored into vmcore, offset will be -1 */ + phdr.p_filesz = 0; + } else { + phdr.p_filesz = cpu_convert_to_target32(memory_mapping->length, endian); + } + phdr.p_memsz = cpu_convert_to_target32(memory_mapping->length, endian); + phdr.p_vaddr = cpu_convert_to_target32(memory_mapping->virt_addr, endian); + + ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s); + if (ret < 0) { + dump_error(s, "dump: failed to write program header table.\n"); + return -1; + } + + return 0; +} + +static int write_elf64_note(DumpState *s) +{ + Elf64_Phdr phdr; + int endian = s->dump_info.d_endian; + target_phys_addr_t begin = s->memory_offset - s->note_size; + int ret; + + memset(&phdr, 0, sizeof(Elf64_Phdr)); + phdr.p_type = cpu_convert_to_target32(PT_NOTE, endian); + phdr.p_offset = cpu_convert_to_target64(begin, endian); + phdr.p_paddr = 0; + phdr.p_filesz = cpu_convert_to_target64(s->note_size, endian); + phdr.p_memsz = cpu_convert_to_target64(s->note_size, endian); + phdr.p_vaddr = 0; + + ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s); + if (ret < 0) { + dump_error(s, "dump: failed to write program header table.\n"); + return -1; + } + + return 0; +} + +static int write_elf64_notes(DumpState *s) +{ + CPUArchState *env; + int ret; + int id; + + for (env = first_cpu; env != NULL; env = env->next_cpu) { + id = cpu_index(env); + ret = cpu_write_elf64_note(fd_write_vmcore, env, id, s); + if (ret < 0) { + dump_error(s, "dump: failed to write elf notes.\n"); + return -1; + } + } + + for (env = first_cpu; env != NULL; env = env->next_cpu) { + ret = cpu_write_elf64_qemunote(fd_write_vmcore, env, s); + if (ret < 0) { + dump_error(s, "dump: failed to write CPU status.\n"); + return -1; + } + } + + return 0; +} + +static int write_elf32_note(DumpState *s) +{ + target_phys_addr_t begin = s->memory_offset - s->note_size; + Elf32_Phdr phdr; + int endian = s->dump_info.d_endian; + int ret; + + memset(&phdr, 0, sizeof(Elf32_Phdr)); + phdr.p_type = cpu_convert_to_target32(PT_NOTE, endian); + phdr.p_offset = cpu_convert_to_target32(begin, endian); + phdr.p_paddr = 0; + phdr.p_filesz = cpu_convert_to_target32(s->note_size, endian); + phdr.p_memsz = cpu_convert_to_target32(s->note_size, endian); + phdr.p_vaddr = 0; + + ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s); + if (ret < 0) { + dump_error(s, "dump: failed to write program header table.\n"); + return -1; + } + + return 0; +} + +static int write_elf32_notes(DumpState *s) +{ + CPUArchState *env; + int ret; + int id; + + for (env = first_cpu; env != NULL; env = env->next_cpu) { + id = cpu_index(env); + ret = cpu_write_elf32_note(fd_write_vmcore, env, id, s); + if (ret < 0) { + dump_error(s, "dump: failed to write elf notes.\n"); + return -1; + } + } + + for (env = first_cpu; env != NULL; env = env->next_cpu) { + ret = cpu_write_elf32_qemunote(fd_write_vmcore, env, s); + if (ret < 0) { + dump_error(s, "dump: failed to write CPU status.\n"); + return -1; + } + } + + return 0; +} + +static int write_elf_section(DumpState *s, int type) +{ + Elf32_Shdr shdr32; + Elf64_Shdr shdr64; + int endian = s->dump_info.d_endian; + int shdr_size; + void *shdr; + int ret; + + if (type == 0) { + shdr_size = sizeof(Elf32_Shdr); + memset(&shdr32, 0, shdr_size); + shdr32.sh_info = cpu_convert_to_target32(s->sh_info, endian); + shdr = &shdr32; + } else { + shdr_size = sizeof(Elf64_Shdr); + memset(&shdr64, 0, shdr_size); + shdr64.sh_info = cpu_convert_to_target32(s->sh_info, endian); + shdr = &shdr64; + } + + ret = fd_write_vmcore(&shdr, shdr_size, s); + if (ret < 0) { + dump_error(s, "dump: failed to write section header table.\n"); + return -1; + } + + return 0; +} + +static int write_data(DumpState *s, void *buf, int length) +{ + int ret; + + ret = fd_write_vmcore(buf, length, s); + if (ret < 0) { + dump_error(s, "dump: failed to save memory.\n"); + return -1; + } + + return 0; +} + +/* write the memroy to vmcore. 1 page per I/O. */ +static int write_memory(DumpState *s, RAMBlock *block, ram_addr_t start, + int64_t size) +{ + int64_t i; + int ret; + + for (i = 0; i < size / TARGET_PAGE_SIZE; i++) { + ret = write_data(s, block->host + start + i * TARGET_PAGE_SIZE, + TARGET_PAGE_SIZE); + if (ret < 0) { + return ret; + } + } + + if ((size % TARGET_PAGE_SIZE) != 0) { + ret = write_data(s, block->host + start + i * TARGET_PAGE_SIZE, + size % TARGET_PAGE_SIZE); + if (ret < 0) { + return ret; + } + } + + return 0; +} + +/* get the memory's offset in the vmcore */ +static target_phys_addr_t get_offset(target_phys_addr_t phys_addr, + DumpState *s) +{ + RAMBlock *block; + target_phys_addr_t offset = s->memory_offset; + int64_t size_in_block, start; + + if (s->has_filter) { + if (phys_addr < s->begin || phys_addr >= s->begin + s->length) { + return -1; + } + } + + QLIST_FOREACH(block, &ram_list.blocks, next) { + if (s->has_filter) { + if (block->offset >= s->begin + s->length || + block->offset + block->length <= s->begin) { + /* This block is out of the range */ + continue; + } + + if (s->begin <= block->offset) { + start = block->offset; + } else { + start = s->begin; + } + + size_in_block = block->length - (start - block->offset); + if (s->begin + s->length < block->offset + block->length) { + size_in_block -= block->offset + block->length - + (s->begin + s->length); + } + } else { + start = block->offset; + size_in_block = block->length; + } + + if (phys_addr >= start && phys_addr < start + size_in_block) { + return phys_addr - start + offset; + } + + offset += size_in_block; + } + + return -1; +} + +static int write_elf_loads(DumpState *s) +{ + target_phys_addr_t offset; + MemoryMapping *memory_mapping; + uint32_t phdr_index = 1; + int ret; + uint32_t max_index; + + if (s->have_section) { + max_index = s->sh_info; + } else { + max_index = s->phdr_num; + } + + QTAILQ_FOREACH(memory_mapping, &s->list.head, next) { + offset = get_offset(memory_mapping->phys_addr, s); + if (s->dump_info.d_class == ELFCLASS64) { + ret = write_elf64_load(s, memory_mapping, phdr_index++, offset); + } else { + ret = write_elf32_load(s, memory_mapping, phdr_index++, offset); + } + + if (ret < 0) { + return -1; + } + + if (phdr_index >= max_index) { + break; + } + } + + return 0; +} + +/* write elf header, PT_NOTE and elf note to vmcore. */ +static int dump_begin(DumpState *s) +{ + int ret; + + /* + * 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) { + ret = write_elf64_header(s); + } else { + ret = write_elf32_header(s); + } + if (ret < 0) { + return -1; + } + + if (s->dump_info.d_class == ELFCLASS64) { + /* write PT_NOTE to vmcore */ + if (write_elf64_note(s) < 0) { + return -1; + } + + /* write all PT_LOAD to vmcore */ + if (write_elf_loads(s) < 0) { + return -1; + } + + /* write section to vmcore */ + if (s->have_section) { + if (write_elf_section(s, 1) < 0) { + return -1; + } + } + + /* write notes to vmcore */ + if (write_elf64_notes(s) < 0) { + return -1; + } + + } else { + /* write PT_NOTE to vmcore */ + if (write_elf32_note(s) < 0) { + return -1; + } + + /* write all PT_LOAD to vmcore */ + if (write_elf_loads(s) < 0) { + return -1; + } + + /* write section to vmcore */ + if (s->have_section) { + if (write_elf_section(s, 0) < 0) { + return -1; + } + } + + /* write notes to vmcore */ + if (write_elf32_notes(s) < 0) { + return -1; + } + } + + return 0; +} + +/* write PT_LOAD to vmcore */ +static int dump_completed(DumpState *s) +{ + dump_cleanup(s); + return 0; +} + +static int get_next_block(DumpState *s, RAMBlock *block) +{ + while (1) { + block = QLIST_NEXT(block, next); + if (!block) { + /* no more block */ + return 1; + } + + s->start = 0; + s->block = block; + if (s->has_filter) { + if (block->offset >= s->begin + s->length || + block->offset + block->length <= s->begin) { + /* This block is out of the range */ + continue; + } + + if (s->begin > block->offset) { + s->start = s->begin - block->offset; + } + } + + return 0; + } +} + +/* write all memory to vmcore */ +static int dump_iterate(DumpState *s) +{ + RAMBlock *block; + int64_t size; + int ret; + + while (1) { + block = s->block; + + size = block->length; + if (s->has_filter) { + size -= s->start; + if (s->begin + s->length < block->offset + block->length) { + size -= block->offset + block->length - (s->begin + s->length); + } + } + ret = write_memory(s, block, s->start, size); + if (ret == -1) { + return ret; + } + + ret = get_next_block(s, block); + if (ret == 1) { + dump_completed(s); + return 0; + } + } +} + +static int create_vmcore(DumpState *s) +{ + int ret; + + ret = dump_begin(s); + if (ret < 0) { + return -1; + } + + ret = dump_iterate(s); + if (ret < 0) { + return -1; + } + + return 0; +} + +static ram_addr_t get_start_block(DumpState *s) +{ + RAMBlock *block; + + if (!s->has_filter) { + s->block = QLIST_FIRST(&ram_list.blocks); + return 0; + } + + QLIST_FOREACH(block, &ram_list.blocks, next) { + if (block->offset >= s->begin + s->length || + block->offset + block->length <= s->begin) { + /* This block is out of the range */ + continue; + } + + s->block = block; + if (s->begin > block->offset) { + s->start = s->begin - block->offset; + } else { + s->start = 0; + } + return s->start; + } + + return -1; +} + +static int dump_init(DumpState *s, int fd, bool paging, bool has_filter, + int64_t begin, int64_t length, Error **errp) +{ + CPUArchState *env; + int nr_cpus; + int ret; + + if (runstate_is_running()) { + vm_stop(RUN_STATE_SAVE_VM); + s->resume = true; + } else { + s->resume = false; + } + + s->errp = errp; + s->fd = fd; + s->has_filter = has_filter; + s->begin = begin; + s->length = length; + s->start = get_start_block(s); + if (s->start == -1) { + error_set(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. + * + * if we use kvm, we should synchronize the register before we get dump + * info. + */ + nr_cpus = 0; + for (env = first_cpu; env != NULL; env = env->next_cpu) { + cpu_synchronize_state(env); + nr_cpus++; + } + + ret = cpu_get_dump_info(&s->dump_info); + if (ret < 0) { + error_set(errp, QERR_UNSUPPORTED); + goto cleanup; + } + + /* get memory mapping */ + memory_mapping_list_init(&s->list); + if (paging) { + qemu_get_guest_memory_mapping(&s->list); + } else { + qemu_get_guest_simple_memory_mapping(&s->list); + } + + 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; + } + } + + s->note_size = cpu_get_note_size(s->dump_info.d_class, + s->dump_info.d_machine, nr_cpus); + 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 0; + +cleanup: + if (s->resume) { + vm_start(); + } + + return -1; +} + +void qmp_dump_guest_memory(bool paging, const char *file, bool has_begin, + int64_t begin, bool has_length, int64_t length, + Error **errp) +{ + const char *p; + int fd = -1; + DumpState *s; + int ret; + + if (has_begin && !has_length) { + error_set(errp, QERR_MISSING_PARAMETER, "length"); + return; + } + if (!has_begin && has_length) { + error_set(errp, QERR_MISSING_PARAMETER, "begin"); + return; + } + +#if !defined(WIN32) + if (strstart(file, "fd:", &p)) { + fd = monitor_get_fd(cur_mon, p); + if (fd == -1) { + error_set(errp, QERR_FD_NOT_FOUND, p); + 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_set(errp, QERR_OPEN_FILE_FAILED, p); + return; + } + } + + if (fd == -1) { + error_set(errp, QERR_INVALID_PARAMETER, "protocol"); + return; + } + + s = g_malloc(sizeof(DumpState)); + + ret = dump_init(s, fd, paging, has_begin, begin, length, errp); + if (ret < 0) { + g_free(s); + return; + } + + if (create_vmcore(s) < 0 && !error_is_set(s->errp)) { + error_set(errp, QERR_IO_ERROR); + } + + g_free(s); +} + +#else +/* we need this function in hmp.c */ +void qmp_dump_guest_memory(bool paging, const char *file, bool has_begin, + int64_t begin, bool has_length, int64_t length, + Error **errp) +{ + error_set(errp, QERR_UNSUPPORTED); +} +#endif -- cgit v1.2.1