From 7cc714c354fc4dbfaeca66156ca331f57bf9653e Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Fri, 7 Nov 2014 17:18:03 +0100 Subject: [PATCH 16/41] dump: make kdump-compressed format available for 'dump-guest-memory' Message-id: <1415380693-16593-17-git-send-email-lersek@redhat.com> Patchwork-id: 62202 O-Subject: [RHEL-7.1 qemu-kvm PATCH 16/26] dump: make kdump-compressed format available for 'dump-guest-memory' Bugzilla: 1157798 RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Luiz Capitulino RH-Acked-by: dgibson From: qiaonuohan Make monitor command 'dump-guest-memory' be able to dump in kdump-compressed format. The command's usage: dump [-p] protocol [begin] [length] [format] 'format' is used to specified the format of vmcore and can be: 1. 'elf': ELF format, without compression 2. 'kdump-zlib': kdump-compressed format, with zlib-compressed 3. 'kdump-lzo': kdump-compressed format, with lzo-compressed 4. 'kdump-snappy': kdump-compressed format, with snappy-compressed Without 'format' being set, it is same as 'elf'. And if non-elf format is specified, paging and filter is not allowed. Note: 1. The kdump-compressed format is readable only with the crash utility and makedumpfile, and it can be smaller than the ELF format because of the compression support. 2. The kdump-compressed format is the 6th edition. Signed-off-by: Qiao Nuohan Reviewed-by: Laszlo Ersek Signed-off-by: Luiz Capitulino (cherry picked from commit b53ccc30c40df52d192e469a86c188a8649c6df3) Signed-off-by: Laszlo Ersek Signed-off-by: Miroslav Rezanina --- dump.c | 131 ++++++++++++++++++++++++++++++++++++++++++++++++++++--- hmp.c | 5 ++- qapi-schema.json | 25 ++++++++++- qmp-commands.hx | 7 ++- 4 files changed, 158 insertions(+), 10 deletions(-) diff --git a/dump.c b/dump.c index fc5530f..c0d5877 100644 --- a/dump.c +++ b/dump.c @@ -1449,6 +1449,64 @@ out: return ret; } +static int create_kdump_vmcore(DumpState *s) +{ + 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) { + dump_error(s, "dump: failed to write start flat header.\n"); + return -1; + } + + ret = write_dump_header(s); + if (ret < 0) { + return -1; + } + + ret = write_dump_bitmap(s); + if (ret < 0) { + return -1; + } + + ret = write_dump_pages(s); + if (ret < 0) { + return -1; + } + + ret = write_end_flat_header(s->fd); + if (ret < 0) { + dump_error(s, "dump: failed to write end flat header.\n"); + return -1; + } + + dump_completed(s); + + return 0; +} + static ram_addr_t get_start_block(DumpState *s) { GuestPhysBlock *block; @@ -1485,7 +1543,8 @@ static void get_max_mapnr(DumpState *s) s->max_mapnr = paddr_to_pfn(last_block->target_end, s->page_shift); } -static int dump_init(DumpState *s, int fd, bool paging, bool has_filter, +static int dump_init(DumpState *s, int fd, bool has_format, + DumpGuestMemoryFormat format, bool paging, bool has_filter, int64_t begin, int64_t length, Error **errp) { CPUArchState *env; @@ -1493,6 +1552,11 @@ static int dump_init(DumpState *s, int fd, bool paging, bool has_filter, Error *err = NULL; int ret; + /* 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; @@ -1563,6 +1627,28 @@ static int dump_init(DumpState *s, int fd, bool paging, bool has_filter, tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), s->page_size); s->len_dump_bitmap = tmp * s->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: + 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 0; + } + if (s->has_filter) { memory_mapping_filter(&s->list, s->begin, s->length); } @@ -1622,14 +1708,25 @@ cleanup: } void qmp_dump_guest_memory(bool paging, const char *file, bool has_begin, - int64_t begin, bool has_length, int64_t length, - Error **errp) + int64_t begin, bool has_length, + int64_t length, bool has_format, + DumpGuestMemoryFormat format, Error **errp) { const char *p; int fd = -1; DumpState *s; int ret; + /* + * 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_set(errp, QERR_MISSING_PARAMETER, "length"); return; @@ -1639,6 +1736,21 @@ void qmp_dump_guest_memory(bool paging, const char *file, bool has_begin, return; } + /* 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); @@ -1663,14 +1775,21 @@ void qmp_dump_guest_memory(bool paging, const char *file, bool has_begin, s = g_malloc0(sizeof(DumpState)); - ret = dump_init(s, fd, paging, has_begin, begin, length, errp); + ret = dump_init(s, fd, has_format, format, 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); + if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { + if (create_kdump_vmcore(s) < 0 && !error_is_set(s->errp)) { + error_set(errp, QERR_IO_ERROR); + } + } else { + if (create_vmcore(s) < 0 && !error_is_set(s->errp)) { + error_set(errp, QERR_IO_ERROR); + } } g_free(s); diff --git a/hmp.c b/hmp.c index b723b26..1805926 100644 --- a/hmp.c +++ b/hmp.c @@ -1195,8 +1195,11 @@ void hmp_dump_guest_memory(Monitor *mon, const QDict *qdict) const char *file = qdict_get_str(qdict, "filename"); bool has_begin = qdict_haskey(qdict, "begin"); bool has_length = qdict_haskey(qdict, "length"); + /* kdump-compressed format is not supported for HMP */ + bool has_format = false; int64_t begin = 0; int64_t length = 0; + enum DumpGuestMemoryFormat dump_format = DUMP_GUEST_MEMORY_FORMAT_ELF; char *prot; if (has_begin) { @@ -1209,7 +1212,7 @@ void hmp_dump_guest_memory(Monitor *mon, const QDict *qdict) prot = g_strconcat("file:", file, NULL); qmp_dump_guest_memory(paging, prot, has_begin, begin, has_length, length, - &errp); + has_format, dump_format, &errp); hmp_handle_error(mon, &errp); g_free(prot); } diff --git a/qapi-schema.json b/qapi-schema.json index d3d4e57..8f81c76 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -2578,6 +2578,24 @@ { 'command': 'device_del', 'data': {'id': 'str'} } ## +# @DumpGuestMemoryFormat: +# +# An enumeration of guest-memory-dump's format. +# +# @elf: elf format +# +# @kdump-zlib: kdump-compressed format with zlib-compressed +# +# @kdump-lzo: kdump-compressed format with lzo-compressed +# +# @kdump-snappy: kdump-compressed format with snappy-compressed +# +# Since: 2.0 +## +{ 'enum': 'DumpGuestMemoryFormat', + 'data': [ 'elf', 'kdump-zlib', 'kdump-lzo', 'kdump-snappy' ] } + +## # @dump-guest-memory # # Dump guest's memory to vmcore. It is a synchronous operation that can take @@ -2613,13 +2631,18 @@ # want to dump all guest's memory, please specify the start @begin # and @length # +# @format: #optional if specified, the format of guest memory dump. But non-elf +# format is conflict with paging and filter, ie. @paging, @begin and +# @length is not allowed to be specified with non-elf @format at the +# same time (since 2.0) +# # Returns: nothing on success # # Since: 1.2 ## { 'command': 'dump-guest-memory', 'data': { 'paging': 'bool', 'protocol': 'str', '*begin': 'int', - '*length': 'int' } } + '*length': 'int', '*format': 'DumpGuestMemoryFormat' } } ## # @netdev_add: diff --git a/qmp-commands.hx b/qmp-commands.hx index e164ff8..61aa3bf 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -885,8 +885,8 @@ EQMP { .name = "dump-guest-memory", - .args_type = "paging:b,protocol:s,begin:i?,end:i?", - .params = "-p protocol [begin] [length]", + .args_type = "paging:b,protocol:s,begin:i?,end:i?,format:s?", + .params = "-p protocol [begin] [length] [format]", .help = "dump guest memory to file", .user_print = monitor_user_noop, .mhandler.cmd_new = qmp_marshal_input_dump_guest_memory, @@ -907,6 +907,9 @@ Arguments: with length together (json-int) - "length": the memory size, in bytes. It's optional, and should be specified with begin together (json-int) +- "format": the format of guest memory dump. It's optional, and can be + elf|kdump-zlib|kdump-lzo|kdump-snappy, but non-elf formats will + conflict with paging and filter, ie. begin and length (json-string) Example: -- 1.8.3.1