diff options
| -rw-r--r-- | dump.c | 164 | ||||
| -rw-r--r-- | include/sysemu/dump.h | 2 |
2 files changed, 166 insertions, 0 deletions
@@ -1001,6 +1001,170 @@ static int write_dump_header(DumpState *s) } } +/* + * 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; + + /* 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 = BUFSIZE_BITMAP * (last_pfn / PFN_BUFBITMAP); + new_offset = BUFSIZE_BITMAP * (pfn / PFN_BUFBITMAP); + + 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, + BUFSIZE_BITMAP) < 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, + BUFSIZE_BITMAP) < 0) { + return -1; + } + + memset(buf, 0, BUFSIZE_BITMAP); + old_offset += BUFSIZE_BITMAP; + } + + /* get the exact place of the bit in the buf, and set it */ + byte = (pfn % PFN_BUFBITMAP) / CHAR_BIT; + bit = (pfn % PFN_BUFBITMAP) % CHAR_BIT; + if (value) { + buf[byte] |= 1u << bit; + } else { + buf[byte] &= ~(1u << bit); + } + + return 0; +} + +/* + * 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; + 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 % s->page_size == 0); + assert(block->target_end % s->page_size == 0); + *pfnptr = paddr_to_pfn(block->target_start, s->page_shift); + if (bufptr) { + *bufptr = block->host_addr; + } + return true; + } + + *pfnptr = *pfnptr + 1; + addr = pfn_to_paddr(*pfnptr, s->page_shift); + + if ((addr >= block->target_start) && + (addr + s->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 % s->page_size == 0); + assert(block->target_end % s->page_size == 0); + *pfnptr = paddr_to_pfn(block->target_start, s->page_shift); + buf = block->host_addr; + } + + if (bufptr) { + *bufptr = buf; + } + + return true; +} + +static int write_dump_bitmap(DumpState *s) +{ + int ret = 0; + uint64_t last_pfn, pfn; + void *dump_bitmap_buf; + size_t num_dumpable; + GuestPhysBlock *block_iter = NULL; + + /* dump_bitmap_buf is used to store dump_bitmap temporarily */ + dump_bitmap_buf = g_malloc0(BUFSIZE_BITMAP); + + 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) { + dump_error(s, "dump: failed to set dump_bitmap.\n"); + ret = -1; + goto out; + } + + last_pfn = pfn; + num_dumpable++; + } + + /* + * set_dump_bitmap will always leave the recently set bit un-sync. Here we + * set last_pfn + PFN_BUFBITMAP to 0 and those set but un-sync bit will be + * synchronized into vmcore. + */ + if (num_dumpable > 0) { + ret = set_dump_bitmap(last_pfn, last_pfn + PFN_BUFBITMAP, false, + dump_bitmap_buf, s); + if (ret < 0) { + dump_error(s, "dump: failed to sync dump_bitmap.\n"); + ret = -1; + goto out; + } + } + + /* number of dumpable pages that will be dumped later */ + s->num_dumpable = num_dumpable; + +out: + g_free(dump_bitmap_buf); + + return ret; +} + static ram_addr_t get_start_block(DumpState *s) { GuestPhysBlock *block; diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h index dfee23873f..6d4d0bcc3c 100644 --- a/include/sysemu/dump.h +++ b/include/sysemu/dump.h @@ -39,6 +39,8 @@ #define PHYS_BASE (0) #define DUMP_LEVEL (1) #define DISKDUMP_HEADER_BLOCKS (1) +#define BUFSIZE_BITMAP (TARGET_PAGE_SIZE) +#define PFN_BUFBITMAP (CHAR_BIT * BUFSIZE_BITMAP) typedef struct ArchDumpInfo { int d_machine; /* Architecture */ |