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/* Copyright (C) 2003 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#define DBTUP_C
#include "Dbtup.hpp"
#include <RefConvert.hpp>
#include <ndb_limits.h>
#include <pc.hpp>
#define ljam() { jamLine(6000 + __LINE__); }
#define ljamEntry() { jamEntryLine(6000 + __LINE__); }
//
// Fixed Allocator
// This module is used to allocate and free fixed size tuples from the
// set of pages attached to a fragment. The fixed size is preset per
// fragment and their can only be one such value per fragment in the
// current implementation.
//
// Public methods
// bool allocTh(Fragrecord* const regFragPtr, # In
// Tablerec* const regTabPtr, # In
// Uint32 pageType, # In
// Signal* signal, # In
// Uint32& pageOffset, # Out
// PagePtr& pagePtr) # In/Out
// This method allocates a fixed size and the pagePtr is a reference
// to the page and pageOffset is the offset in the page of the tuple.
//
// freeTh()
// This method is used to free a tuple header in normal transaction
// handling.
//
// freeThSr()
// This method is used to free a tuple as part of executing the undo
// log records.
//
// getThAtPageSr()
// This method is used to allocate a tuple on a set page as part of
// undo log execution.
//
//
// Private methods
// getThAtPage()
// This method gets a tuple from a page with free tuples.
//
// convertThPage()
// Convert an empty page into a page of free tuples in a linked list.
//
// getEmptyPageThCopy()
// A page recently taken from set of empty pages on fragment is made
// part of the copy pages.
//
// getEmptyPageTh()
// A page recently taken from the set of empty pages on the fragment is
// is made part of the set of free pages with fixed size tuples in the
// fragment.
//
bool Dbtup::allocTh(Fragrecord* const regFragPtr,
Tablerec* const regTabPtr,
Uint32 pageType,
Signal* signal,
Uint32& pageOffset,
PagePtr& pagePtr)
{
if (pageType == SAME_PAGE) {
ljam();
ptrCheckGuard(pagePtr, cnoOfPage, page);
if (pagePtr.p->pageWord[ZPAGE_STATE_POS] == ZTH_MM_FREE) {
ljam();
getThAtPage(regFragPtr, pagePtr.p, signal, pageOffset);
return true;
}//if
pageType = NORMAL_PAGE;
}//if
if (pageType == COPY_PAGE) {
/* ---------------------------------------------------------------- */
// Allocate a tuple header for the copy of the tuple header
/* ---------------------------------------------------------------- */
if (regFragPtr->thFreeCopyFirst == RNIL) {
/* ---------------------------------------------------------------- */
// No page in list with free tuple header exists
/* ---------------------------------------------------------------- */
if (regFragPtr->noCopyPagesAlloc < ZMAX_NO_COPY_PAGES) {
ljam();
/* ---------------------------------------------------------------- */
// We have not yet allocated the maximum number of copy pages for
// this fragment.
/* ---------------------------------------------------------------- */
pagePtr.i = getEmptyPage(regFragPtr);
if (pagePtr.i != RNIL) {
ljam();
/* ---------------------------------------------------------------- */
// We have empty pages already allocated to this fragment. Allocate
// one of those as copy page.
/* ---------------------------------------------------------------- */
ptrCheckGuard(pagePtr, cnoOfPage, page);
getEmptyPageThCopy(regFragPtr, signal, pagePtr.p);
/* ---------------------------------------------------------------- */
// Convert page into a tuple header page.
/* ---------------------------------------------------------------- */
convertThPage(regTabPtr->tupheadsize, pagePtr.p);
getThAtPage(regFragPtr, pagePtr.p, signal, pageOffset);
return true;
}//if
}//if
} else {
ljam();
/* ---------------------------------------------------------------- */
/* NORMAL PATH WHEN COPY PAGE REQUESTED, GET PAGE POINTER */
/* AND THEN GOTO COMMON HANDLING OF GET TUPLE HEADER AT PAGE. */
/* ---------------------------------------------------------------- */
pagePtr.i = getRealpid(regFragPtr, regFragPtr->thFreeCopyFirst);
ptrCheckGuard(pagePtr, cnoOfPage, page);
getThAtPage(regFragPtr, pagePtr.p, signal, pageOffset);
return true;
}//if
}//if
/* ---------------------------------------------------------------- */
/* EITHER NORMAL PAGE REQUESTED OR ALLOCATION FROM COPY PAGE */
/* FAILED. TRY ALLOCATING FROM NORMAL PAGE. */
/* ---------------------------------------------------------------- */
Uint32 fragPageId = regFragPtr->thFreeFirst;
if (fragPageId == RNIL) {
/* ---------------------------------------------------------------- */
// No prepared tuple header page with free entries exists.
/* ---------------------------------------------------------------- */
pagePtr.i = getEmptyPage(regFragPtr);
if (pagePtr.i != RNIL) {
ljam();
/* ---------------------------------------------------------------- */
// We found empty pages on the fragment. Allocate an empty page and
// convert it into a tuple header page and put it in thFreeFirst-list.
/* ---------------------------------------------------------------- */
ptrCheckGuard(pagePtr, cnoOfPage, page);
getEmptyPageTh(regFragPtr, signal, pagePtr.p);
convertThPage(regTabPtr->tupheadsize, pagePtr.p);
getThAtPage(regFragPtr, pagePtr.p, signal, pageOffset);
return true;
} else {
ljam();
/* ---------------------------------------------------------------- */
/* THERE ARE NO EMPTY PAGES. MEMORY CAN NOT BE ALLOCATED. */
/* ---------------------------------------------------------------- */
terrorCode = ZMEM_NOMEM_ERROR;
return false;
}//if
} else {
ljam();
/* ---------------------------------------------------------------- */
/* THIS SHOULD BE THE COMMON PATH THROUGH THE CODE, FREE */
/* COPY PAGE EXISTED. */
/* ---------------------------------------------------------------- */
pagePtr.i = getRealpid(regFragPtr, fragPageId);
ptrCheckGuard(pagePtr, cnoOfPage, page);
getThAtPage(regFragPtr, pagePtr.p, signal, pageOffset);
return true;
}//if
ndbrequire(false); // Dead code
return false;
}//Dbtup::allocTh()
void Dbtup::convertThPage(Uint32 Tupheadsize,
Page* const regPagePtr)
{
Uint32 ctpConstant = Tupheadsize << 16;
Uint32 nextTuple = ZPAGE_HEADER_SIZE + Tupheadsize;
Uint32 endOfList;
/*
ASSUMES AT LEAST ONE TUPLE HEADER FITS AND THEREFORE NO HANDLING
OF ZERO AS EXTREME CASE
*/
do {
ljam();
endOfList = nextTuple - Tupheadsize;
regPagePtr->pageWord[endOfList] = ctpConstant + nextTuple;
nextTuple += Tupheadsize;
} while (nextTuple <= ZWORDS_ON_PAGE);
regPagePtr->pageWord[endOfList] = ctpConstant;
Uint32 startOfList = ZPAGE_HEADER_SIZE;
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = (startOfList << 16) + endOfList;
}//Dbtup::convertThPage()
void Dbtup::getEmptyPageTh(Fragrecord* const regFragPtr,
Signal* signal,
Page* const regPagePtr)
{
if (isUndoLoggingNeeded(regFragPtr, regPagePtr->pageWord[ZPAGE_FRAG_PAGE_ID_POS])) {
cprAddUndoLogPageHeader(signal,
regPagePtr,
regFragPtr);
}//if
regPagePtr->pageWord[ZPAGE_NEXT_POS] = regFragPtr->thFreeFirst;
regPagePtr->pageWord[ZPAGE_STATE_POS] = ZTH_MM_FREE;
regFragPtr->thFreeFirst = regPagePtr->pageWord[ZPAGE_FRAG_PAGE_ID_POS];
ndbrequire(regFragPtr->thFreeFirst != (RNIL -1));
}//Dbtup::getEmptyPageTh()
void Dbtup::getEmptyPageThCopy(Fragrecord* const regFragPtr,
Signal* signal,
Page* const regPagePtr)
{
if (isUndoLoggingNeeded(regFragPtr, regPagePtr->pageWord[ZPAGE_FRAG_PAGE_ID_POS])) {
cprAddUndoLogPageHeader(signal,
regPagePtr,
regFragPtr);
}//if
regPagePtr->pageWord[ZPAGE_NEXT_POS] = regFragPtr->thFreeCopyFirst;
regPagePtr->pageWord[ZPAGE_STATE_POS] = ZTH_MM_FREE_COPY;
regFragPtr->thFreeCopyFirst = regPagePtr->pageWord[ZPAGE_FRAG_PAGE_ID_POS];
regFragPtr->noCopyPagesAlloc++;
}//Dbtup::getEmptyPageThCopy()
void Dbtup::getThAtPage(Fragrecord* const regFragPtr,
Page* const regPagePtr,
Signal* signal,
Uint32& pageOffset)
{
Uint32 freeListHeader = regPagePtr->pageWord[ZFREELIST_HEADER_POS];
Uint32 startTuple = freeListHeader >> 16;
Uint32 endTuple = freeListHeader & 0xffff;
pageOffset = startTuple; /* START IS THE ONE ALLOCATED */
if (startTuple > 0) {
if (startTuple != endTuple) {
/* ---------------------------------------------------------------- */
/* NOT THE LAST, SIMPLY RESHUFFLE POINTERS. */
/* ---------------------------------------------------------------- */
ndbrequire(startTuple < ZWORDS_ON_PAGE);
startTuple = regPagePtr->pageWord[startTuple] & 0xffff;
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = endTuple +
(startTuple << 16);
return;
} else {
/* ---------------------------------------------------------------- */
/* THIS WAS THE LAST TUPLE HEADER IN THIS PAGE. REMOVE IT FROM*/
/* THE TUPLE HEADER FREE LIST OR TH COPY FREE LIST. ALSO SET */
/* A PROPER PAGE STATE. */
/* */
/* WE ALSO HAVE TO INSERT AN UNDO LOG ENTRY TO ENSURE PAGE */
/* ARE MAINTAINED EVEN AFTER A SYSTEM CRASH. */
/* ---------------------------------------------------------------- */
if (isUndoLoggingNeeded(regFragPtr,
regPagePtr->pageWord[ZPAGE_FRAG_PAGE_ID_POS])) {
cprAddUndoLogPageHeader(signal,
regPagePtr,
regFragPtr);
}//if
if (regPagePtr->pageWord[ZPAGE_STATE_POS] == ZTH_MM_FREE) {
ljam();
regFragPtr->thFreeFirst = regPagePtr->pageWord[ZPAGE_NEXT_POS];
regPagePtr->pageWord[ZPAGE_STATE_POS] = ZTH_MM_FULL;
} else if (regPagePtr->pageWord[ZPAGE_STATE_POS] == ZTH_MM_FREE_COPY) {
ljam();
regFragPtr->thFreeCopyFirst = regPagePtr->pageWord[ZPAGE_NEXT_POS];
regPagePtr->pageWord[ZPAGE_STATE_POS] = ZTH_MM_FULL_COPY;
} else {
ndbrequire(false);
}//if
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = 0;
regPagePtr->pageWord[ZPAGE_NEXT_POS] = RNIL;
}//if
} else {
ndbrequire(false);
}//if
return;
}//Dbtup::getThAtPage()
void Dbtup::getThAtPageSr(Page* const regPagePtr,
Uint32& pageOffset)
{
Uint32 freeListHeader = regPagePtr->pageWord[ZFREELIST_HEADER_POS];
Uint32 startTuple = freeListHeader >> 16;
Uint32 endTuple = freeListHeader & 0xffff;
ndbrequire(startTuple > 0);
pageOffset = startTuple; /* START IS THE ONE ALLOCATED */
if (startTuple == endTuple) {
ljam();
/* ---------------------------------------------------------------- */
/* THIS WAS THE LAST TUPLE HEADER IN THIS PAGE. SINCE WE ARE */
/* UNDOING PAGE UPDATES WE SHALL NOT DO ANYTHING ABOUT THE */
/* PAGE HEADER. THIS IS DONE BY SEPARATE LOG RECORDS. */
/* ---------------------------------------------------------------- */
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = 0;
} else {
ljam();
/* ---------------------------------------------------------------- */
/* NOT THE LAST, SIMPLY RESHUFFLE POINTERS. */
/* ---------------------------------------------------------------- */
ndbrequire(startTuple < ZWORDS_ON_PAGE);
startTuple = regPagePtr->pageWord[startTuple] & 0xffff; /* GET NEXT POINTER */
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = endTuple + (startTuple << 16);
}//if
}//Dbtup::getThAtPageSr()
void Dbtup::freeTh(Fragrecord* const regFragPtr,
Tablerec* const regTabPtr,
Signal* signal,
Page* const regPagePtr,
Uint32 freePageOffset)
{
Uint32 startOfList = regPagePtr->pageWord[ZFREELIST_HEADER_POS] >> 16;
Uint32 endOfList = regPagePtr->pageWord[ZFREELIST_HEADER_POS] & 0xffff;
/* LINK THE NOW FREE TUPLE SPACE INTO BEGINNING OF FREE LIST OF OF THE PAGE */
/* SET THE SIZE OF THE NEW FREE SPACE AND LINK TO THE OLD START OF FREELIST */
ndbrequire(freePageOffset < ZWORDS_ON_PAGE);
regPagePtr->pageWord[freePageOffset] = (regTabPtr->tupheadsize << 16) +
startOfList;
if (endOfList == 0) {
ljam();
ndbrequire(startOfList == 0);
/* ---------------------------------------------------------------- */
/* THE PAGE WAS PREVIOUSLY FULL, NO EMPTY SPACE AT ALL. */
/* THIS ENTRY WILL THEN BE BOTH THE START AND THE END OF THE */
/* LIST. IT WILL ALSO BE PUT ON THE PROPER FREE LIST. */
/* */
/* UPDATE OF NEXT POINTER AND PAGE STATE MUST BE LOGGED TO */
/* THE UNDO LOG TO ENSURE THAT FREE LISTS ARE OK AFTER A */
/* SYSTEM RESTART. */
/* ---------------------------------------------------------------- */
if (isUndoLoggingNeeded(regFragPtr, regPagePtr->pageWord[ZPAGE_FRAG_PAGE_ID_POS])) {
cprAddUndoLogPageHeader(signal,
regPagePtr,
regFragPtr);
}//if
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = (freePageOffset << 16) + freePageOffset;
if (regPagePtr->pageWord[ZPAGE_STATE_POS] == ZTH_MM_FULL) {
ljam();
regPagePtr->pageWord[ZPAGE_NEXT_POS] = regFragPtr->thFreeFirst;
regFragPtr->thFreeFirst = regPagePtr->pageWord[ZPAGE_FRAG_PAGE_ID_POS];
regPagePtr->pageWord[ZPAGE_STATE_POS] = ZTH_MM_FREE;
} else {
ndbrequire(regPagePtr->pageWord[ZPAGE_STATE_POS] == ZTH_MM_FULL_COPY);
ljam();
regPagePtr->pageWord[ZPAGE_NEXT_POS] = regFragPtr->thFreeCopyFirst;
regFragPtr->thFreeCopyFirst = regPagePtr->pageWord[ZPAGE_FRAG_PAGE_ID_POS];
regPagePtr->pageWord[ZPAGE_STATE_POS] = ZTH_MM_FREE_COPY;
}//if
} else {
ljam();
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = (freePageOffset << 16) + endOfList;
}//if
}//Dbtup::freeTh()
void Dbtup::freeThSr(Tablerec* const regTabPtr,
Page* const regPagePtr,
Uint32 freePageOffset)
{
/* ------------------------------------------------------------------------ */
/* LINK THE NOW FREE TUPLE SPACE INTO BEGINNING OF FREE LIST OF OF THE PAGE */
/* SET THE SIZE OF THE NEW FREE SPACE AND LINK TO THE OLD START OF FREELIST */
/* ------------------------------------------------------------------------ */
Uint32 startOfList = regPagePtr->pageWord[ZFREELIST_HEADER_POS] >> 16;
Uint32 endOfList = regPagePtr->pageWord[ZFREELIST_HEADER_POS] & 0xffff;
ndbrequire(freePageOffset < ZWORDS_ON_PAGE);
regPagePtr->pageWord[freePageOffset] = (regTabPtr->tupheadsize << 16) + startOfList;
if (endOfList == 0) {
ljam();
ndbrequire(startOfList == 0);
/* ---------------------------------------------------------------- */
/* THE PAGE WAS PREVIOUSLY FULL, NO EMPTY SPACE AT ALL. */
/* THIS ENTRY WILL THEN BE BOTH THE START AND THE END OF THE */
/* LIST. IT WILL ALSO BE PUT ON THE PROPER FREE LIST. */
/* ---------------------------------------------------------------- */
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = (freePageOffset << 16) + freePageOffset;
} else {
ljam();
regPagePtr->pageWord[ZFREELIST_HEADER_POS] = (freePageOffset << 16) + endOfList;
}//if
}//Dbtup::freeThSr()
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