From b53ccc30c40df52d192e469a86c188a8649c6df3 Mon Sep 17 00:00:00 2001 From: qiaonuohan Date: Tue, 18 Feb 2014 14:11:36 +0800 Subject: dump: make kdump-compressed format available for 'dump-guest-memory' 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 --- dump.c | 131 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 125 insertions(+), 6 deletions(-) (limited to 'dump.c') diff --git a/dump.c b/dump.c index a7b5117aa5..fb0c8962af 100644 --- a/dump.c +++ b/dump.c @@ -1443,6 +1443,64 @@ 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; @@ -1479,7 +1537,8 @@ 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) { CPUState *cpu; @@ -1487,6 +1546,11 @@ 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; @@ -1557,6 +1621,28 @@ 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); } @@ -1616,14 +1702,25 @@ 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; @@ -1633,6 +1730,21 @@ 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); @@ -1657,14 +1769,21 @@ 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); -- cgit v1.2.3