diff options
Diffstat (limited to 'innobase/buf/buf0buf.c')
| -rw-r--r-- | innobase/buf/buf0buf.c | 110 |
1 files changed, 81 insertions, 29 deletions
diff --git a/innobase/buf/buf0buf.c b/innobase/buf/buf0buf.c index e000d862403..246a60a61cd 100644 --- a/innobase/buf/buf0buf.c +++ b/innobase/buf/buf0buf.c @@ -209,12 +209,12 @@ ibool buf_debug_prints = FALSE; /* If this is set TRUE, /************************************************************************ Calculates a page checksum which is stored to the page when it is written -to a file. Note that we must be careful to calculate the same value -on 32-bit and 64-bit architectures. */ +to a file. Note that we must be careful to calculate the same value on +32-bit and 64-bit architectures. */ ulint -buf_calc_page_checksum( -/*===================*/ +buf_calc_page_new_checksum( +/*=======================*/ /* out: checksum */ byte* page) /* in: buffer page */ { @@ -222,12 +222,39 @@ buf_calc_page_checksum( /* Since the fields FIL_PAGE_FILE_FLUSH_LSN and ..._ARCH_LOG_NO are written outside the buffer pool to the first pages of data - files, we have to skip them in page checksum calculation */ + files, we have to skip them in the page checksum calculation. + We must also skip the field FIL_PAGE_SPACE_OR_CHKSUM where the + checksum is stored, and also the last 8 bytes of page because + there we store the old formula checksum. */ + + checksum = ut_fold_binary(page + FIL_PAGE_OFFSET, + FIL_PAGE_FILE_FLUSH_LSN - FIL_PAGE_OFFSET) + + ut_fold_binary(page + FIL_PAGE_DATA, + UNIV_PAGE_SIZE - FIL_PAGE_DATA + - FIL_PAGE_END_LSN_OLD_CHKSUM); + checksum = checksum & 0xFFFFFFFF; + + return(checksum); +} + +/************************************************************************ +In versions < 4.0.14 and < 4.1.1 there was a bug that the checksum only +looked at the first few bytes of the page. This calculates that old +checksum. +NOTE: we must first store the new formula checksum to +FIL_PAGE_SPACE_OR_CHKSUM before calculating and storing this old checksum +because this takes that field as an input! */ + +ulint +buf_calc_page_old_checksum( +/*=======================*/ + /* out: checksum */ + byte* page) /* in: buffer page */ +{ + ulint checksum; checksum = ut_fold_binary(page, FIL_PAGE_FILE_FLUSH_LSN); - + ut_fold_binary(page + FIL_PAGE_DATA, - UNIV_PAGE_SIZE - FIL_PAGE_DATA - - FIL_PAGE_END_LSN); + checksum = checksum & 0xFFFFFFFF; return(checksum); @@ -243,27 +270,47 @@ buf_page_is_corrupted( byte* read_buf) /* in: a database page */ { ulint checksum; + ulint old_checksum; + ulint checksum_field; + ulint old_checksum_field; + + if (mach_read_from_4(read_buf + FIL_PAGE_LSN + 4) + != mach_read_from_4(read_buf + UNIV_PAGE_SIZE + - FIL_PAGE_END_LSN_OLD_CHKSUM + 4)) { + + /* Stored log sequence numbers at the start and the end + of page do not match */ + + return(TRUE); + } - checksum = buf_calc_page_checksum(read_buf); + old_checksum = buf_calc_page_old_checksum(read_buf); - /* Note that InnoDB initializes empty pages to zero, and - early versions of InnoDB did not store page checksum to - the 4 most significant bytes of the page lsn field at the - end of a page: */ + old_checksum_field = mach_read_from_4(read_buf + UNIV_PAGE_SIZE + - FIL_PAGE_END_LSN_OLD_CHKSUM); + + /* There are 2 valid formulas for old_checksum_field: + 1. Very old versions of InnoDB only stored 8 byte lsn to the start + and the end of the page. + 2. Newer InnoDB versions store the old formula checksum there. */ - if ((mach_read_from_4(read_buf + FIL_PAGE_LSN + 4) - != mach_read_from_4(read_buf + UNIV_PAGE_SIZE - - FIL_PAGE_END_LSN + 4)) - || (checksum != mach_read_from_4(read_buf - + UNIV_PAGE_SIZE - - FIL_PAGE_END_LSN) - && mach_read_from_4(read_buf + FIL_PAGE_LSN) - != mach_read_from_4(read_buf - + UNIV_PAGE_SIZE - - FIL_PAGE_END_LSN))) { + if (old_checksum_field != mach_read_from_4(read_buf + FIL_PAGE_LSN) + && old_checksum_field != old_checksum) { + return(TRUE); } + checksum = buf_calc_page_new_checksum(read_buf); + checksum_field = mach_read_from_4(read_buf + FIL_PAGE_SPACE_OR_CHKSUM); + + /* InnoDB versions < 4.0.14 and < 4.1.1 stored the space id + (always equal to 0), to FIL_PAGE_SPACE_SPACE_OR_CHKSUM */ + + if (checksum_field != 0 && checksum_field != checksum) { + + return(TRUE); + } + return(FALSE); } @@ -277,6 +324,7 @@ buf_page_print( { dict_index_t* index; ulint checksum; + ulint old_checksum; char* buf; buf = mem_alloc(4 * UNIV_PAGE_SIZE); @@ -291,19 +339,23 @@ buf_page_print( mem_free(buf); - checksum = buf_calc_page_checksum(read_buf); + checksum = buf_calc_page_new_checksum(read_buf); + old_checksum = buf_calc_page_old_checksum(read_buf); ut_print_timestamp(stderr); - fprintf(stderr, " InnoDB: Page checksum %lu stored checksum %lu\n", - checksum, mach_read_from_4(read_buf - + UNIV_PAGE_SIZE - - FIL_PAGE_END_LSN)); + fprintf(stderr, +" InnoDB: Page checksum %lu, prior-to-4.0.14-form checksum %lu\n" +"InnoDB: stored checksum %lu, prior-to-4.0.14-form stored checksum %lu\n", + checksum, old_checksum, + mach_read_from_4(read_buf + FIL_PAGE_SPACE_OR_CHKSUM), + mach_read_from_4(read_buf + UNIV_PAGE_SIZE + - FIL_PAGE_END_LSN_OLD_CHKSUM)); fprintf(stderr, "InnoDB: Page lsn %lu %lu, low 4 bytes of lsn at page end %lu\n", mach_read_from_4(read_buf + FIL_PAGE_LSN), mach_read_from_4(read_buf + FIL_PAGE_LSN + 4), mach_read_from_4(read_buf + UNIV_PAGE_SIZE - - FIL_PAGE_END_LSN + 4)); + - FIL_PAGE_END_LSN_OLD_CHKSUM + 4)); if (mach_read_from_2(read_buf + TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_TYPE) == TRX_UNDO_INSERT) { fprintf(stderr, |