/*
* Create a table space
*
* Only superusers can create a tablespace. This seems a reasonable restriction
* since we're determining the system layout and, anyway, we probably have
* root if we're doing this kind of activity
*/
void
CreateTableSpace(CreateTableSpaceStmt *stmt)
{
#ifdef HAVE_SYMLINK
Relation rel;
Datum values[Natts_pg_tablespace];
char nulls[Natts_pg_tablespace];
HeapTuple tuple;
Oid tablespaceoid;
char *location;
char *linkloc;
Oid ownerId;
/* validate */
/* don't call this in a transaction block */
PreventTransactionChain((void *) stmt, "CREATE TABLESPACE");
/* Must be super user */
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied to create tablespace \"%s\"",
stmt->tablespacename),
errhint("Must be superuser to create a tablespace.")));
/* However, the eventual owner of the tablespace need not be */
if (stmt->owner)
ownerId = get_roleid_checked(stmt->owner);
else
ownerId = GetUserId();
/* Unix-ify the offered path, and strip any trailing slashes */
location = pstrdup(stmt->location);
canonicalize_path(location);
/* disallow quotes, else CREATE DATABASE would be at risk */
if (strchr(location, '\''))
ereport(ERROR,
(errcode(ERRCODE_INVALID_NAME),
errmsg("tablespace location may not contain single quotes")));
/*
* Allowing relative paths seems risky
*
* this also helps us ensure that location is not empty or whitespace
*/
if (!is_absolute_path(location))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location must be an absolute path")));
/*
* Check that location isn't too long. Remember that we're going to append
* '/<dboid>/<relid>.<nnn>' (XXX but do we ever form the whole path
* explicitly? This may be overly conservative.)
*/
if (strlen(location) >= (MAXPGPATH - 1 - 10 - 1 - 10 - 1 - 10))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location \"%s\" is too long",
location)));
/*
* Disallow creation of tablespaces named "pg_xxx"; we reserve this
* namespace for system purposes.
*/
if (!allowSystemTableMods && IsReservedName(stmt->tablespacename))
ereport(ERROR,
(errcode(ERRCODE_RESERVED_NAME),
errmsg("unacceptable tablespace name \"%s\"",
stmt->tablespacename),
errdetail("The prefix \"pg_\" is reserved for system tablespaces.")));
/*
* Check that there is no other tablespace by this name. (The unique
* index would catch this anyway, but might as well give a friendlier
* message.)
*/
if (OidIsValid(get_tablespace_oid(stmt->tablespacename)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("tablespace \"%s\" already exists",
stmt->tablespacename)));
/*
* Insert tuple into pg_tablespace. The purpose of doing this first is to
* lock the proposed tablename against other would-be creators. The
* insertion will roll back if we find problems below.
*/
rel = heap_open(TableSpaceRelationId, RowExclusiveLock);
MemSet(nulls, ' ', Natts_pg_tablespace);
values[Anum_pg_tablespace_spcname - 1] =
DirectFunctionCall1(namein, CStringGetDatum(stmt->tablespacename));
values[Anum_pg_tablespace_spcowner - 1] =
ObjectIdGetDatum(ownerId);
values[Anum_pg_tablespace_spclocation - 1] =
DirectFunctionCall1(textin, CStringGetDatum(location));
nulls[Anum_pg_tablespace_spcacl - 1] = 'n';
tuple = heap_formtuple(rel->rd_att, values, nulls);
tablespaceoid = simple_heap_insert(rel, tuple);
CatalogUpdateIndexes(rel, tuple);
heap_freetuple(tuple);
/* Record dependency on owner */
recordDependencyOnOwner(TableSpaceRelationId, tablespaceoid, ownerId);
/*
* Attempt to coerce target directory to safe permissions. If this fails,
* it doesn't exist or has the wrong owner.
*/
if (chmod(location, 0700) != 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not set permissions on directory \"%s\": %m",
location)));
/*
* Check the target directory is empty.
*/
if (!directory_is_empty(location))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("directory \"%s\" is not empty",
location)));
/*
* Create the PG_VERSION file in the target directory. This has several
* purposes: to make sure we can write in the directory, to prevent
* someone from creating another tablespace pointing at the same directory
* (the emptiness check above will fail), and to label tablespace
* directories by PG version.
*/
set_short_version(location);
/*
* All seems well, create the symlink
*/
linkloc = (char *) palloc(10 + 10 + 1);
sprintf(linkloc, "pg_tblspc/%u", tablespaceoid);
if (symlink(location, linkloc) < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not create symbolic link \"%s\": %m",
linkloc)));
/* Record the filesystem change in XLOG */
{
xl_tblspc_create_rec xlrec;
XLogRecData rdata[2];
xlrec.ts_id = tablespaceoid;
rdata[0].data = (char *) &xlrec;
rdata[0].len = offsetof(xl_tblspc_create_rec, ts_path);
rdata[0].buffer = InvalidBuffer;
rdata[0].next = &(rdata[1]);
rdata[1].data = (char *) location;
rdata[1].len = strlen(location) + 1;
rdata[1].buffer = InvalidBuffer;
rdata[1].next = NULL;
(void) XLogInsert(RM_TBLSPC_ID, XLOG_TBLSPC_CREATE, rdata);
}
pfree(linkloc);
pfree(location);
/* We keep the lock on pg_tablespace until commit */
heap_close(rel, NoLock);
#else /* !HAVE_SYMLINK */
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("tablespaces are not supported on this platform")));
#endif /* HAVE_SYMLINK */
}
/*
* Build a pending-list page from the given array of tuples, and write it out.
*
* Returns amount of free space left on the page.
*/
static int32
writeListPage(Relation index, Buffer buffer,
IndexTuple *tuples, int32 ntuples, BlockNumber rightlink)
{
Page page = BufferGetPage(buffer);
int32 i,
freesize,
size = 0;
OffsetNumber l,
off;
char *workspace;
char *ptr;
/* workspace could be a local array; we use palloc for alignment */
workspace = palloc(BLCKSZ);
START_CRIT_SECTION();
GinInitBuffer(buffer, GIN_LIST);
off = FirstOffsetNumber;
ptr = workspace;
for (i = 0; i < ntuples; i++)
{
int this_size = IndexTupleSize(tuples[i]);
memcpy(ptr, tuples[i], this_size);
ptr += this_size;
size += this_size;
l = PageAddItem(page, (Item) tuples[i], this_size, off, false, false);
if (l == InvalidOffsetNumber)
elog(ERROR, "failed to add item to index page in \"%s\"",
RelationGetRelationName(index));
off++;
}
Assert(size <= BLCKSZ); /* else we overran workspace */
GinPageGetOpaque(page)->rightlink = rightlink;
/*
* tail page may contain only whole row(s) or final part of row placed on
* previous pages (a "row" here meaning all the index tuples generated for
* one heap tuple)
*/
if (rightlink == InvalidBlockNumber)
{
GinPageSetFullRow(page);
GinPageGetOpaque(page)->maxoff = 1;
}
else
{
GinPageGetOpaque(page)->maxoff = 0;
}
MarkBufferDirty(buffer);
if (RelationNeedsWAL(index))
{
XLogRecData rdata[2];
ginxlogInsertListPage data;
XLogRecPtr recptr;
data.node = index->rd_node;
data.blkno = BufferGetBlockNumber(buffer);
data.rightlink = rightlink;
data.ntuples = ntuples;
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char *) &data;
rdata[0].len = sizeof(ginxlogInsertListPage);
rdata[0].next = rdata + 1;
rdata[1].buffer = InvalidBuffer;
rdata[1].data = workspace;
rdata[1].len = size;
rdata[1].next = NULL;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_INSERT_LISTPAGE, rdata);
PageSetLSN(page, recptr);
}
/* get free space before releasing buffer */
freesize = PageGetExactFreeSpace(page);
UnlockReleaseBuffer(buffer);
END_CRIT_SECTION();
pfree(workspace);
return freesize;
}
Datum
ginbuild(PG_FUNCTION_ARGS)
{
Relation heap = (Relation) PG_GETARG_POINTER(0);
Relation index = (Relation) PG_GETARG_POINTER(1);
IndexInfo *indexInfo = (IndexInfo *) PG_GETARG_POINTER(2);
IndexBuildResult *result;
double reltuples;
GinBuildState buildstate;
Buffer RootBuffer,
MetaBuffer;
ItemPointerData *list;
Datum entry;
uint32 nlist;
MemoryContext oldCtx;
OffsetNumber attnum;
if (RelationGetNumberOfBlocks(index) != 0)
elog(ERROR, "index \"%s\" already contains data",
RelationGetRelationName(index));
initGinState(&buildstate.ginstate, index);
/* initialize the meta page */
MetaBuffer = GinNewBuffer(index);
/* initialize the root page */
RootBuffer = GinNewBuffer(index);
START_CRIT_SECTION();
GinInitMetabuffer(MetaBuffer);
MarkBufferDirty(MetaBuffer);
GinInitBuffer(RootBuffer, GIN_LEAF);
MarkBufferDirty(RootBuffer);
if (!index->rd_istemp)
{
XLogRecPtr recptr;
XLogRecData rdata;
Page page;
rdata.buffer = InvalidBuffer;
rdata.data = (char *) &(index->rd_node);
rdata.len = sizeof(RelFileNode);
rdata.next = NULL;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_CREATE_INDEX, &rdata);
page = BufferGetPage(RootBuffer);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
page = BufferGetPage(MetaBuffer);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
}
UnlockReleaseBuffer(MetaBuffer);
UnlockReleaseBuffer(RootBuffer);
END_CRIT_SECTION();
/* build the index */
buildstate.indtuples = 0;
/*
* create a temporary memory context that is reset once for each tuple
* inserted into the index
*/
buildstate.tmpCtx = AllocSetContextCreate(CurrentMemoryContext,
"Gin build temporary context",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
buildstate.funcCtx = AllocSetContextCreate(buildstate.tmpCtx,
"Gin build temporary context for user-defined function",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
buildstate.accum.ginstate = &buildstate.ginstate;
ginInitBA(&buildstate.accum);
/*
* Do the heap scan. We disallow sync scan here because dataPlaceToPage
* prefers to receive tuples in TID order.
*/
reltuples = IndexBuildHeapScan(heap, index, indexInfo, false,
ginBuildCallback, (void *) &buildstate);
/* dump remaining entries to the index */
oldCtx = MemoryContextSwitchTo(buildstate.tmpCtx);
ginBeginBAScan(&buildstate.accum);
while ((list = ginGetEntry(&buildstate.accum, &attnum, &entry, &nlist)) != NULL)
{
/* there could be many entries, so be willing to abort here */
CHECK_FOR_INTERRUPTS();
ginEntryInsert(index, &buildstate.ginstate, attnum, entry, list, nlist, TRUE);
}
MemoryContextSwitchTo(oldCtx);
MemoryContextDelete(buildstate.tmpCtx);
/*
* Return statistics
*/
result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
result->heap_tuples = reltuples;
result->index_tuples = buildstate.indtuples;
PG_RETURN_POINTER(result);
}
/*
* Vacuum a root page when it is also a leaf
*
* On the root, we just delete any dead leaf tuples; no fancy business
*/
static void
vacuumLeafRoot(spgBulkDeleteState *bds, Relation index, Buffer buffer)
{
Page page = BufferGetPage(buffer);
spgxlogVacuumRoot xlrec;
OffsetNumber toDelete[MaxIndexTuplesPerPage];
OffsetNumber i,
max = PageGetMaxOffsetNumber(page);
xlrec.nDelete = 0;
/* Scan page, identify tuples to delete, accumulate stats */
for (i = FirstOffsetNumber; i <= max; i++)
{
SpGistLeafTuple lt;
lt = (SpGistLeafTuple) PageGetItem(page,
PageGetItemId(page, i));
if (lt->tupstate == SPGIST_LIVE)
{
Assert(ItemPointerIsValid(<->heapPtr));
if (bds->callback(<->heapPtr, bds->callback_state))
{
bds->stats->tuples_removed += 1;
toDelete[xlrec.nDelete] = i;
xlrec.nDelete++;
}
else
{
bds->stats->num_index_tuples += 1;
}
}
else
{
/* all tuples on root should be live */
elog(ERROR, "unexpected SPGiST tuple state: %d",
lt->tupstate);
}
}
if (xlrec.nDelete == 0)
return; /* nothing more to do */
/* Do the update */
START_CRIT_SECTION();
/* The tuple numbers are in order, so we can use PageIndexMultiDelete */
PageIndexMultiDelete(page, toDelete, xlrec.nDelete);
MarkBufferDirty(buffer);
if (RelationNeedsWAL(index))
{
XLogRecPtr recptr;
XLogBeginInsert();
/* Prepare WAL record */
STORE_STATE(&bds->spgstate, xlrec.stateSrc);
XLogRegisterData((char *) &xlrec, SizeOfSpgxlogVacuumRoot);
/* sizeof(xlrec) should be a multiple of sizeof(OffsetNumber) */
XLogRegisterData((char *) toDelete,
sizeof(OffsetNumber) * xlrec.nDelete);
XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
recptr = XLogInsert(RM_SPGIST_ID, XLOG_SPGIST_VACUUM_ROOT);
PageSetLSN(page, recptr);
}
END_CRIT_SECTION();
}
/*
* Deletes pending list pages up to (not including) newHead page.
* If newHead == InvalidBlockNumber then function drops the whole list.
*
* metapage is pinned and exclusive-locked throughout this function.
*
* Returns true if another cleanup process is running concurrently
* (if so, we can just abandon our own efforts)
*/
static bool
shiftList(Relation index, Buffer metabuffer, BlockNumber newHead,
bool fill_fsm, IndexBulkDeleteResult *stats)
{
Page metapage;
GinMetaPageData *metadata;
BlockNumber blknoToDelete;
metapage = BufferGetPage(metabuffer);
metadata = GinPageGetMeta(metapage);
blknoToDelete = metadata->head;
do
{
Page page;
int i;
int64 nDeletedHeapTuples = 0;
ginxlogDeleteListPages data;
Buffer buffers[GIN_NDELETE_AT_ONCE];
BlockNumber freespace[GIN_NDELETE_AT_ONCE];
data.ndeleted = 0;
while (data.ndeleted < GIN_NDELETE_AT_ONCE && blknoToDelete != newHead)
{
freespace[data.ndeleted] = blknoToDelete;
buffers[data.ndeleted] = ReadBuffer(index, blknoToDelete);
LockBuffer(buffers[data.ndeleted], GIN_EXCLUSIVE);
page = BufferGetPage(buffers[data.ndeleted]);
data.ndeleted++;
if (GinPageIsDeleted(page))
{
/* concurrent cleanup process is detected */
for (i = 0; i < data.ndeleted; i++)
UnlockReleaseBuffer(buffers[i]);
return true;
}
nDeletedHeapTuples += GinPageGetOpaque(page)->maxoff;
blknoToDelete = GinPageGetOpaque(page)->rightlink;
}
if (stats)
stats->pages_deleted += data.ndeleted;
/*
* This operation touches an unusually large number of pages, so
* prepare the XLogInsert machinery for that before entering the
* critical section.
*/
if (RelationNeedsWAL(index))
XLogEnsureRecordSpace(data.ndeleted, 0);
START_CRIT_SECTION();
metadata->head = blknoToDelete;
Assert(metadata->nPendingPages >= data.ndeleted);
metadata->nPendingPages -= data.ndeleted;
Assert(metadata->nPendingHeapTuples >= nDeletedHeapTuples);
metadata->nPendingHeapTuples -= nDeletedHeapTuples;
if (blknoToDelete == InvalidBlockNumber)
{
metadata->tail = InvalidBlockNumber;
metadata->tailFreeSize = 0;
metadata->nPendingPages = 0;
metadata->nPendingHeapTuples = 0;
}
MarkBufferDirty(metabuffer);
for (i = 0; i < data.ndeleted; i++)
{
page = BufferGetPage(buffers[i]);
GinPageGetOpaque(page)->flags = GIN_DELETED;
MarkBufferDirty(buffers[i]);
}
if (RelationNeedsWAL(index))
{
XLogRecPtr recptr;
XLogBeginInsert();
XLogRegisterBuffer(0, metabuffer, REGBUF_WILL_INIT);
for (i = 0; i < data.ndeleted; i++)
XLogRegisterBuffer(i + 1, buffers[i], REGBUF_WILL_INIT);
memcpy(&data.metadata, metadata, sizeof(GinMetaPageData));
XLogRegisterData((char *) &data,
sizeof(ginxlogDeleteListPages));
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_DELETE_LISTPAGE);
PageSetLSN(metapage, recptr);
for (i = 0; i < data.ndeleted; i++)
{
page = BufferGetPage(buffers[i]);
PageSetLSN(page, recptr);
}
}
for (i = 0; i < data.ndeleted; i++)
UnlockReleaseBuffer(buffers[i]);
END_CRIT_SECTION();
for (i = 0; fill_fsm && i < data.ndeleted; i++)
RecordFreeIndexPage(index, freespace[i]);
} while (blknoToDelete != newHead);
return false;
}
/*
* Insert a new item to a page.
*
* Returns true if the insertion was finished. On false, the page was split and
* the parent needs to be updated. (A root split returns true as it doesn't
* need any further action by the caller to complete.)
*
* When inserting a downlink to an internal page, 'childbuf' contains the
* child page that was split. Its GIN_INCOMPLETE_SPLIT flag will be cleared
* atomically with the insert. Also, the existing item at offset stack->off
* in the target page is updated to point to updateblkno.
*
* stack->buffer is locked on entry, and is kept locked.
* Likewise for childbuf, if given.
*/
static bool
ginPlaceToPage(GinBtree btree, GinBtreeStack *stack,
void *insertdata, BlockNumber updateblkno,
Buffer childbuf, GinStatsData *buildStats)
{
Page page = BufferGetPage(stack->buffer);
bool result;
GinPlaceToPageRC rc;
uint16 xlflags = 0;
Page childpage = NULL;
Page newlpage = NULL,
newrpage = NULL;
void *ptp_workspace = NULL;
XLogRecData payloadrdata[10];
MemoryContext tmpCxt;
MemoryContext oldCxt;
/*
* We do all the work of this function and its subfunctions in a temporary
* memory context. This avoids leakages and simplifies APIs, since some
* subfunctions allocate storage that has to survive until we've finished
* the WAL insertion.
*/
tmpCxt = AllocSetContextCreate(CurrentMemoryContext,
"ginPlaceToPage temporary context",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
oldCxt = MemoryContextSwitchTo(tmpCxt);
if (GinPageIsData(page))
xlflags |= GIN_INSERT_ISDATA;
if (GinPageIsLeaf(page))
{
xlflags |= GIN_INSERT_ISLEAF;
Assert(!BufferIsValid(childbuf));
Assert(updateblkno == InvalidBlockNumber);
}
else
{
Assert(BufferIsValid(childbuf));
Assert(updateblkno != InvalidBlockNumber);
childpage = BufferGetPage(childbuf);
}
/*
* See if the incoming tuple will fit on the page. beginPlaceToPage will
* decide if the page needs to be split, and will compute the split
* contents if so. See comments for beginPlaceToPage and execPlaceToPage
* functions for more details of the API here.
*/
rc = btree->beginPlaceToPage(btree, stack->buffer, stack,
insertdata, updateblkno,
&ptp_workspace,
&newlpage, &newrpage,
payloadrdata);
if (rc == GPTP_NO_WORK)
{
/* Nothing to do */
result = true;
}
else if (rc == GPTP_INSERT)
{
/* It will fit, perform the insertion */
START_CRIT_SECTION();
/* Perform the page update, and set up WAL data about it */
btree->execPlaceToPage(btree, stack->buffer, stack,
insertdata, updateblkno,
ptp_workspace, payloadrdata);
MarkBufferDirty(stack->buffer);
/* An insert to an internal page finishes the split of the child. */
if (BufferIsValid(childbuf))
{
GinPageGetOpaque(childpage)->flags &= ~GIN_INCOMPLETE_SPLIT;
MarkBufferDirty(childbuf);
}
if (RelationNeedsWAL(btree->index))
{
XLogRecPtr recptr;
XLogRecData rdata[3];
ginxlogInsert xlrec;
BlockIdData childblknos[2];
xlrec.node = btree->index->rd_node;
xlrec.blkno = BufferGetBlockNumber(stack->buffer);
xlrec.flags = xlflags;
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char *) &xlrec;
rdata[0].len = sizeof(ginxlogInsert);
/*
* Log information about child if this was an insertion of a
* downlink.
*/
if (BufferIsValid(childbuf))
{
rdata[0].next = &rdata[1];
BlockIdSet(&childblknos[0], BufferGetBlockNumber(childbuf));
BlockIdSet(&childblknos[1], GinPageGetOpaque(childpage)->rightlink);
rdata[1].buffer = InvalidBuffer;
rdata[1].data = (char *) childblknos;
rdata[1].len = sizeof(BlockIdData) * 2;
rdata[1].next = &rdata[2];
rdata[2].buffer = childbuf;
rdata[2].buffer_std = true;
rdata[2].data = NULL;
rdata[2].len = 0;
rdata[2].next = payloadrdata;
}
else
rdata[0].next = payloadrdata;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_INSERT, rdata);
PageSetLSN(page, recptr);
if (BufferIsValid(childbuf))
PageSetLSN(childpage, recptr);
}
END_CRIT_SECTION();
/* Insertion is complete. */
result = true;
}
else if (rc == GPTP_SPLIT)
{
/*
* Didn't fit, need to split. The split has been computed in newlpage
* and newrpage, which are pointers to palloc'd pages, not associated
* with buffers. stack->buffer is not touched yet.
*/
Buffer rbuffer;
BlockNumber savedRightLink;
ginxlogSplit data;
Buffer lbuffer = InvalidBuffer;
Page newrootpg = NULL;
/* Get a new index page to become the right page */
rbuffer = GinNewBuffer(btree->index);
/* During index build, count the new page */
if (buildStats)
{
if (btree->isData)
buildStats->nDataPages++;
else
buildStats->nEntryPages++;
}
savedRightLink = GinPageGetOpaque(page)->rightlink;
/* Begin setting up WAL record (which we might not use) */
data.node = btree->index->rd_node;
data.rblkno = BufferGetBlockNumber(rbuffer);
data.flags = xlflags;
if (BufferIsValid(childbuf))
{
data.leftChildBlkno = BufferGetBlockNumber(childbuf);
data.rightChildBlkno = GinPageGetOpaque(childpage)->rightlink;
}
else
data.leftChildBlkno = data.rightChildBlkno = InvalidBlockNumber;
if (stack->parent == NULL)
{
/*
* splitting the root, so we need to allocate new left page and
* place pointers to left and right page on root page.
*/
lbuffer = GinNewBuffer(btree->index);
/* During index build, count the new left page */
if (buildStats)
{
if (btree->isData)
buildStats->nDataPages++;
else
buildStats->nEntryPages++;
}
/*
* root never has a right-link, so we borrow the rrlink field to
* store the root block number.
*/
data.rrlink = BufferGetBlockNumber(stack->buffer);
data.lblkno = BufferGetBlockNumber(lbuffer);
data.flags |= GIN_SPLIT_ROOT;
GinPageGetOpaque(newrpage)->rightlink = InvalidBlockNumber;
GinPageGetOpaque(newlpage)->rightlink = BufferGetBlockNumber(rbuffer);
/*
* Construct a new root page containing downlinks to the new left
* and right pages. (Do this in a temporary copy rather than
* overwriting the original page directly, since we're not in the
* critical section yet.)
*/
newrootpg = PageGetTempPage(newrpage);
GinInitPage(newrootpg, GinPageGetOpaque(newlpage)->flags & ~(GIN_LEAF | GIN_COMPRESSED), BLCKSZ);
btree->fillRoot(btree, newrootpg,
BufferGetBlockNumber(lbuffer), newlpage,
BufferGetBlockNumber(rbuffer), newrpage);
}
else
{
/* splitting a non-root page */
data.rrlink = savedRightLink;
data.lblkno = BufferGetBlockNumber(stack->buffer);
GinPageGetOpaque(newrpage)->rightlink = savedRightLink;
GinPageGetOpaque(newlpage)->flags |= GIN_INCOMPLETE_SPLIT;
GinPageGetOpaque(newlpage)->rightlink = BufferGetBlockNumber(rbuffer);
}
/*
* OK, we have the new contents of the left page in a temporary copy
* now (newlpage), and likewise for the new contents of the
* newly-allocated right block. The original page is still unchanged.
*
* If this is a root split, we also have a temporary page containing
* the new contents of the root.
*/
START_CRIT_SECTION();
MarkBufferDirty(rbuffer);
MarkBufferDirty(stack->buffer);
/*
* Restore the temporary copies over the real buffers.
*/
if (stack->parent == NULL)
{
/* Splitting the root, three pages to update */
MarkBufferDirty(lbuffer);
memcpy(page, newrootpg, BLCKSZ);
memcpy(BufferGetPage(lbuffer), newlpage, BLCKSZ);
memcpy(BufferGetPage(rbuffer), newrpage, BLCKSZ);
}
else
{
/* Normal split, only two pages to update */
memcpy(page, newlpage, BLCKSZ);
memcpy(BufferGetPage(rbuffer), newrpage, BLCKSZ);
}
/* We also clear childbuf's INCOMPLETE_SPLIT flag, if passed */
if (BufferIsValid(childbuf))
{
GinPageGetOpaque(childpage)->flags &= ~GIN_INCOMPLETE_SPLIT;
MarkBufferDirty(childbuf);
}
/* write WAL record */
if (RelationNeedsWAL(btree->index))
{
XLogRecData rdata[2];
XLogRecPtr recptr;
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char *) &data;
rdata[0].len = sizeof(ginxlogSplit);
if (BufferIsValid(childbuf))
{
rdata[0].next = &rdata[1];
rdata[1].buffer = childbuf;
rdata[1].buffer_std = true;
rdata[1].data = NULL;
rdata[1].len = 0;
rdata[1].next = payloadrdata;
}
else
rdata[0].next = payloadrdata;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_SPLIT, rdata);
PageSetLSN(page, recptr);
PageSetLSN(BufferGetPage(rbuffer), recptr);
if (stack->parent == NULL)
PageSetLSN(BufferGetPage(lbuffer), recptr);
if (BufferIsValid(childbuf))
PageSetLSN(childpage, recptr);
}
END_CRIT_SECTION();
/*
* We can release the locks/pins on the new pages now, but keep
* stack->buffer locked. childbuf doesn't get unlocked either.
*/
UnlockReleaseBuffer(rbuffer);
if (stack->parent == NULL)
UnlockReleaseBuffer(lbuffer);
/*
* If we split the root, we're done. Otherwise the split is not
* complete until the downlink for the new page has been inserted to
* the parent.
*/
result = (stack->parent == NULL);
}
else
{
elog(ERROR, "invalid return code from GIN placeToPage method: %d", rc);
result = false; /* keep compiler quiet */
}
/* Clean up temp context */
MemoryContextSwitchTo(oldCxt);
MemoryContextDelete(tmpCxt);
return result;
}
/*
* fills WAL record for vacuum leaf page
*/
static void
xlogVacuumPage(Relation index, Buffer buffer)
{
Page page = BufferGetPage(buffer);
XLogRecPtr recptr;
XLogRecData rdata[3];
ginxlogVacuumPage data;
char *backup;
char itups[BLCKSZ];
uint32 len = 0;
Assert(GinPageIsLeaf(page));
if (index->rd_istemp)
return;
data.node = index->rd_node;
data.blkno = BufferGetBlockNumber(buffer);
if (GinPageIsData(page))
{
backup = GinDataPageGetData(page);
data.nitem = GinPageGetOpaque(page)->maxoff;
if (data.nitem)
len = MAXALIGN(sizeof(ItemPointerData) * data.nitem);
}
else
{
char *ptr;
OffsetNumber i;
ptr = backup = itups;
for (i = FirstOffsetNumber; i <= PageGetMaxOffsetNumber(page); i++)
{
IndexTuple itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, i));
memcpy(ptr, itup, IndexTupleSize(itup));
ptr += MAXALIGN(IndexTupleSize(itup));
}
data.nitem = PageGetMaxOffsetNumber(page);
len = ptr - backup;
}
rdata[0].buffer = buffer;
rdata[0].buffer_std = (GinPageIsData(page)) ? FALSE : TRUE;
rdata[0].len = 0;
rdata[0].data = NULL;
rdata[0].next = rdata + 1;
rdata[1].buffer = InvalidBuffer;
rdata[1].len = sizeof(ginxlogVacuumPage);
rdata[1].data = (char *) &data;
if (len == 0)
{
rdata[1].next = NULL;
}
else
{
rdata[1].next = rdata + 2;
rdata[2].buffer = InvalidBuffer;
rdata[2].len = len;
rdata[2].data = backup;
rdata[2].next = NULL;
}
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_VACUUM_PAGE, rdata);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
}
/*
* _bitmap_log_updatewords() -- log updating bitmap words in one or
* two bitmap pages.
*
* If nextBuffer is Invalid, we only update one page.
*
*/
void
_bitmap_log_updatewords(Relation rel,
Buffer lovBuffer, OffsetNumber lovOffset,
Buffer firstBuffer, Buffer secondBuffer,
bool new_lastpage)
{
Page firstPage = NULL;
Page secondPage = NULL;
BMBitmap firstBitmap;
BMBitmap secondBitmap;
BMBitmapOpaque firstOpaque;
BMBitmapOpaque secondOpaque;
xl_bm_updatewords xlBitmapWords;
XLogRecPtr recptr;
XLogRecData rdata[1];
firstPage = BufferGetPage(firstBuffer);
firstBitmap = (BMBitmap) PageGetContentsMaxAligned(firstPage);
firstOpaque = (BMBitmapOpaque)PageGetSpecialPointer(firstPage);
xlBitmapWords.bm_two_pages = false;
xlBitmapWords.bm_first_blkno = BufferGetBlockNumber(firstBuffer);
memcpy(&xlBitmapWords.bm_first_cwords,
firstBitmap->cwords,
BM_NUM_OF_HRL_WORDS_PER_PAGE * sizeof(BM_HRL_WORD));
memcpy(&xlBitmapWords.bm_first_hwords,
firstBitmap->hwords,
BM_NUM_OF_HEADER_WORDS * sizeof(BM_HRL_WORD));
xlBitmapWords.bm_first_last_tid = firstOpaque->bm_last_tid_location;
xlBitmapWords.bm_first_num_cwords =
firstOpaque->bm_hrl_words_used;
xlBitmapWords.bm_next_blkno = firstOpaque->bm_bitmap_next;
if (BufferIsValid(secondBuffer))
{
secondPage = BufferGetPage(secondBuffer);
secondBitmap = (BMBitmap) PageGetContentsMaxAligned(secondPage);
secondOpaque = (BMBitmapOpaque)PageGetSpecialPointer(secondPage);
xlBitmapWords.bm_two_pages = true;
xlBitmapWords.bm_second_blkno = BufferGetBlockNumber(secondBuffer);
memcpy(&xlBitmapWords.bm_second_cwords,
secondBitmap->cwords,
BM_NUM_OF_HRL_WORDS_PER_PAGE * sizeof(BM_HRL_WORD));
memcpy(&xlBitmapWords.bm_second_hwords,
secondBitmap->hwords,
BM_NUM_OF_HEADER_WORDS * sizeof(BM_HRL_WORD));
xlBitmapWords.bm_second_last_tid = secondOpaque->bm_last_tid_location;
xlBitmapWords.bm_second_num_cwords =
secondOpaque->bm_hrl_words_used;
xlBitmapWords.bm_next_blkno = secondOpaque->bm_bitmap_next;
}
// Fetch gp_persistent_relation_node information that will be added to XLOG record.
RelationFetchGpRelationNodeForXLog(rel);
xlBitmapWords.bm_node = rel->rd_node;
xlBitmapWords.bm_persistentTid = rel->rd_relationnodeinfo.persistentTid;
xlBitmapWords.bm_persistentSerialNum = rel->rd_relationnodeinfo.persistentSerialNum;
xlBitmapWords.bm_lov_blkno = BufferGetBlockNumber(lovBuffer);
xlBitmapWords.bm_lov_offset = lovOffset;
xlBitmapWords.bm_new_lastpage = new_lastpage;
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char*)&xlBitmapWords;
rdata[0].len = sizeof(xl_bm_updatewords);
rdata[0].next = NULL;
recptr = XLogInsert(RM_BITMAP_ID, XLOG_BITMAP_UPDATEWORDS, rdata);
PageSetLSN(firstPage, recptr);
PageSetTLI(firstPage, ThisTimeLineID);
if (BufferIsValid(secondBuffer))
{
PageSetLSN(secondPage, recptr);
PageSetTLI(secondPage, ThisTimeLineID);
}
if (new_lastpage)
{
Page lovPage = BufferGetPage(lovBuffer);
PageSetLSN(lovPage, recptr);
PageSetTLI(lovPage, ThisTimeLineID);
}
}
/*
* _bitmap_log_bitmapwords() -- log new bitmap words to be inserted.
*/
void
_bitmap_log_bitmapwords(Relation rel, Buffer bitmapBuffer, Buffer lovBuffer,
OffsetNumber lovOffset, BMTIDBuffer* buf,
uint64 words_written, uint64 tidnum, BlockNumber nextBlkno,
bool isLast, bool isFirst)
{
Page bitmapPage;
BMBitmapOpaque bitmapPageOpaque;
xl_bm_bitmapwords *xlBitmapWords;
XLogRecPtr recptr;
XLogRecData rdata[1];
uint64* lastTids;
BM_HRL_WORD* cwords;
BM_HRL_WORD* hwords;
int lastTids_size;
int cwords_size;
int hwords_size;
Page lovPage = BufferGetPage(lovBuffer);
// Fetch gp_persistent_relation_node information that will be added to XLOG record.
RelationFetchGpRelationNodeForXLog(rel);
lastTids_size = buf->curword * sizeof(uint64);
cwords_size = buf->curword * sizeof(BM_HRL_WORD);
hwords_size = (BM_CALC_H_WORDS(buf->curword)) *
sizeof(BM_HRL_WORD);
bitmapPage = BufferGetPage(bitmapBuffer);
bitmapPageOpaque =
(BMBitmapOpaque)PageGetSpecialPointer(bitmapPage);
xlBitmapWords = (xl_bm_bitmapwords *)
palloc0(MAXALIGN(sizeof(xl_bm_bitmapwords)) + MAXALIGN(lastTids_size) +
MAXALIGN(cwords_size) + MAXALIGN(hwords_size));
xlBitmapWords->bm_node = rel->rd_node;
xlBitmapWords->bm_persistentTid = rel->rd_relationnodeinfo.persistentTid;
xlBitmapWords->bm_persistentSerialNum = rel->rd_relationnodeinfo.persistentSerialNum;
xlBitmapWords->bm_blkno = BufferGetBlockNumber(bitmapBuffer);
xlBitmapWords->bm_next_blkno = nextBlkno;
xlBitmapWords->bm_last_tid = bitmapPageOpaque->bm_last_tid_location;
xlBitmapWords->bm_lov_blkno = BufferGetBlockNumber(lovBuffer);
xlBitmapWords->bm_lov_offset = lovOffset;
xlBitmapWords->bm_last_compword = buf->last_compword;
xlBitmapWords->bm_last_word = buf->last_word;
xlBitmapWords->lov_words_header =
(buf->is_last_compword_fill) ? 2 : 0;
xlBitmapWords->bm_last_setbit = tidnum;
xlBitmapWords->bm_is_last = isLast;
xlBitmapWords->bm_is_first = isFirst;
xlBitmapWords->bm_start_wordno = buf->start_wordno;
xlBitmapWords->bm_words_written = words_written;
xlBitmapWords->bm_num_cwords = buf->curword;
lastTids = (uint64*)(((char*)xlBitmapWords) +
MAXALIGN(sizeof(xl_bm_bitmapwords)));
memcpy(lastTids, buf->last_tids,
buf->curword * sizeof(uint64));
cwords = (BM_HRL_WORD*)(((char*)xlBitmapWords) +
MAXALIGN(sizeof(xl_bm_bitmapwords)) + MAXALIGN(lastTids_size));
memcpy(cwords, buf->cwords, cwords_size);
hwords = (BM_HRL_WORD*)(((char*)xlBitmapWords) +
MAXALIGN(sizeof(xl_bm_bitmapwords)) + MAXALIGN(lastTids_size) +
MAXALIGN(cwords_size));
memcpy(hwords, buf->hwords, hwords_size);
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char*)xlBitmapWords;
rdata[0].len = MAXALIGN(sizeof(xl_bm_bitmapwords)) + MAXALIGN(lastTids_size) +
MAXALIGN(cwords_size) + MAXALIGN(hwords_size);
rdata[0].next = NULL;
recptr = XLogInsert(RM_BITMAP_ID, XLOG_BITMAP_INSERT_WORDS, rdata);
PageSetLSN(bitmapPage, recptr);
PageSetTLI(bitmapPage, ThisTimeLineID);
PageSetLSN(lovPage, recptr);
PageSetTLI(lovPage, ThisTimeLineID);
pfree(xlBitmapWords);
}
/*
* Write WAL record of a page split.
*/
XLogRecPtr
gistXLogSplit(RelFileNode node, BlockNumber blkno, bool page_is_leaf,
SplitedPageLayout *dist,
BlockNumber origrlink, GistNSN orignsn,
Buffer leftchildbuf)
{
XLogRecData *rdata;
gistxlogPageSplit xlrec;
SplitedPageLayout *ptr;
int npage = 0,
cur;
XLogRecPtr recptr;
for (ptr = dist; ptr; ptr = ptr->next)
npage++;
rdata = (XLogRecData *) palloc(sizeof(XLogRecData) * (npage * 2 + 2));
xlrec.node = node;
xlrec.origblkno = blkno;
xlrec.origrlink = origrlink;
xlrec.orignsn = orignsn;
xlrec.origleaf = page_is_leaf;
xlrec.npage = (uint16) npage;
xlrec.leftchild =
BufferIsValid(leftchildbuf) ? BufferGetBlockNumber(leftchildbuf) : InvalidBlockNumber;
rdata[0].data = (char *) &xlrec;
rdata[0].len = sizeof(gistxlogPageSplit);
rdata[0].buffer = InvalidBuffer;
cur = 1;
/*
* Include a full page image of the child buf. (only necessary if a
* checkpoint happened since the child page was split)
*/
if (BufferIsValid(leftchildbuf))
{
rdata[cur - 1].next = &(rdata[cur]);
rdata[cur].data = NULL;
rdata[cur].len = 0;
rdata[cur].buffer = leftchildbuf;
rdata[cur].buffer_std = true;
cur++;
}
for (ptr = dist; ptr; ptr = ptr->next)
{
rdata[cur - 1].next = &(rdata[cur]);
rdata[cur].buffer = InvalidBuffer;
rdata[cur].data = (char *) &(ptr->block);
rdata[cur].len = sizeof(gistxlogPage);
cur++;
rdata[cur - 1].next = &(rdata[cur]);
rdata[cur].buffer = InvalidBuffer;
rdata[cur].data = (char *) (ptr->list);
rdata[cur].len = ptr->lenlist;
cur++;
}
rdata[cur - 1].next = NULL;
recptr = XLogInsert(RM_GIST_ID, XLOG_GIST_PAGE_SPLIT, rdata);
pfree(rdata);
return recptr;
}
/*
* Write XLOG record describing a page update. The update can include any
* number of deletions and/or insertions of tuples on a single index page.
*
* If this update inserts a downlink for a split page, also record that
* the F_FOLLOW_RIGHT flag on the child page is cleared and NSN set.
*
* Note that both the todelete array and the tuples are marked as belonging
* to the target buffer; they need not be stored in XLOG if XLogInsert decides
* to log the whole buffer contents instead. Also, we take care that there's
* at least one rdata item referencing the buffer, even when ntodelete and
* ituplen are both zero; this ensures that XLogInsert knows about the buffer.
*/
XLogRecPtr
gistXLogUpdate(RelFileNode node, Buffer buffer,
OffsetNumber *todelete, int ntodelete,
IndexTuple *itup, int ituplen,
Buffer leftchildbuf)
{
XLogRecData *rdata;
gistxlogPageUpdate *xlrec;
int cur,
i;
XLogRecPtr recptr;
rdata = (XLogRecData *) palloc(sizeof(XLogRecData) * (4 + ituplen));
xlrec = (gistxlogPageUpdate *) palloc(sizeof(gistxlogPageUpdate));
xlrec->node = node;
xlrec->blkno = BufferGetBlockNumber(buffer);
xlrec->ntodelete = ntodelete;
xlrec->leftchild =
BufferIsValid(leftchildbuf) ? BufferGetBlockNumber(leftchildbuf) : InvalidBlockNumber;
rdata[0].buffer = buffer;
rdata[0].buffer_std = true;
rdata[0].data = NULL;
rdata[0].len = 0;
rdata[0].next = &(rdata[1]);
rdata[1].data = (char *) xlrec;
rdata[1].len = sizeof(gistxlogPageUpdate);
rdata[1].buffer = InvalidBuffer;
rdata[1].next = &(rdata[2]);
rdata[2].data = (char *) todelete;
rdata[2].len = sizeof(OffsetNumber) * ntodelete;
rdata[2].buffer = buffer;
rdata[2].buffer_std = true;
cur = 3;
/* new tuples */
for (i = 0; i < ituplen; i++)
{
rdata[cur - 1].next = &(rdata[cur]);
rdata[cur].data = (char *) (itup[i]);
rdata[cur].len = IndexTupleSize(itup[i]);
rdata[cur].buffer = buffer;
rdata[cur].buffer_std = true;
cur++;
}
/*
* Include a full page image of the child buf. (only necessary if a
* checkpoint happened since the child page was split)
*/
if (BufferIsValid(leftchildbuf))
{
rdata[cur - 1].next = &(rdata[cur]);
rdata[cur].data = NULL;
rdata[cur].len = 0;
rdata[cur].buffer = leftchildbuf;
rdata[cur].buffer_std = true;
cur++;
}
rdata[cur - 1].next = NULL;
recptr = XLogInsert(RM_GIST_ID, XLOG_GIST_PAGE_UPDATE, rdata);
pfree(rdata);
return recptr;
}
/*
* _bt_pagedel() -- Delete a page from the b-tree.
*
* This action unlinks the page from the b-tree structure, removing all
* pointers leading to it --- but not touching its own left and right links.
* The page cannot be physically reclaimed right away, since other processes
* may currently be trying to follow links leading to the page; they have to
* be allowed to use its right-link to recover. See nbtree/README.
*
* On entry, the target buffer must be pinned and read-locked. This lock and
* pin will be dropped before exiting.
*
* Returns the number of pages successfully deleted (zero on failure; could
* be more than one if parent blocks were deleted).
*
* NOTE: this leaks memory. Rather than trying to clean up everything
* carefully, it's better to run it in a temp context that can be reset
* frequently.
*/
int
_bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
{
BlockNumber target,
leftsib,
rightsib,
parent;
OffsetNumber poffset,
maxoff;
uint32 targetlevel,
ilevel;
ItemId itemid;
BTItem targetkey,
btitem;
ScanKey itup_scankey;
BTStack stack;
Buffer lbuf,
rbuf,
pbuf;
bool parent_half_dead;
bool parent_one_child;
bool rightsib_empty;
Buffer metabuf = InvalidBuffer;
Page metapg = NULL;
BTMetaPageData *metad = NULL;
Page page;
BTPageOpaque opaque;
/*
* We can never delete rightmost pages nor root pages. While at it, check
* that page is not already deleted and is empty.
*/
page = BufferGetPage(buf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
if (P_RIGHTMOST(opaque) || P_ISROOT(opaque) || P_ISDELETED(opaque) ||
P_FIRSTDATAKEY(opaque) <= PageGetMaxOffsetNumber(page))
{
_bt_relbuf(rel, buf);
return 0;
}
/*
* Save info about page, including a copy of its high key (it must have
* one, being non-rightmost).
*/
target = BufferGetBlockNumber(buf);
targetlevel = opaque->btpo.level;
leftsib = opaque->btpo_prev;
itemid = PageGetItemId(page, P_HIKEY);
targetkey = CopyBTItem((BTItem) PageGetItem(page, itemid));
/*
* We need to get an approximate pointer to the page's parent page. Use
* the standard search mechanism to search for the page's high key; this
* will give us a link to either the current parent or someplace to its
* left (if there are multiple equal high keys). To avoid deadlocks, we'd
* better drop the target page lock first.
*/
_bt_relbuf(rel, buf);
/* we need a scan key to do our search, so build one */
itup_scankey = _bt_mkscankey(rel, &(targetkey->bti_itup));
/* find the leftmost leaf page containing this key */
stack = _bt_search(rel, rel->rd_rel->relnatts, itup_scankey, false,
&lbuf, BT_READ);
/* don't need a pin on that either */
_bt_relbuf(rel, lbuf);
/*
* If we are trying to delete an interior page, _bt_search did more than
* we needed. Locate the stack item pointing to our parent level.
*/
ilevel = 0;
for (;;)
{
if (stack == NULL)
elog(ERROR, "not enough stack items");
if (ilevel == targetlevel)
break;
stack = stack->bts_parent;
ilevel++;
}
/*
* We have to lock the pages we need to modify in the standard order:
* moving right, then up. Else we will deadlock against other writers.
*
* So, we need to find and write-lock the current left sibling of the
* target page. The sibling that was current a moment ago could have
* split, so we may have to move right. This search could fail if either
* the sibling or the target page was deleted by someone else meanwhile;
* if so, give up. (Right now, that should never happen, since page
* deletion is only done in VACUUM and there shouldn't be multiple VACUUMs
* concurrently on the same table.)
*/
if (leftsib != P_NONE)
{
lbuf = _bt_getbuf(rel, leftsib, BT_WRITE);
page = BufferGetPage(lbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
while (P_ISDELETED(opaque) || opaque->btpo_next != target)
{
/* step right one page */
leftsib = opaque->btpo_next;
_bt_relbuf(rel, lbuf);
if (leftsib == P_NONE)
{
elog(LOG, "no left sibling (concurrent deletion?) in \"%s\"",
RelationGetRelationName(rel));
return 0;
}
lbuf = _bt_getbuf(rel, leftsib, BT_WRITE);
page = BufferGetPage(lbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
}
}
else
lbuf = InvalidBuffer;
/*
* Next write-lock the target page itself. It should be okay to take just
* a write lock not a superexclusive lock, since no scans would stop on an
* empty page.
*/
buf = _bt_getbuf(rel, target, BT_WRITE);
page = BufferGetPage(buf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
/*
* Check page is still empty etc, else abandon deletion. The empty check
* is necessary since someone else might have inserted into it while we
* didn't have it locked; the others are just for paranoia's sake.
*/
if (P_RIGHTMOST(opaque) || P_ISROOT(opaque) || P_ISDELETED(opaque) ||
P_FIRSTDATAKEY(opaque) <= PageGetMaxOffsetNumber(page))
{
_bt_relbuf(rel, buf);
if (BufferIsValid(lbuf))
_bt_relbuf(rel, lbuf);
return 0;
}
if (opaque->btpo_prev != leftsib)
elog(ERROR, "left link changed unexpectedly in block %u of \"%s\"",
target, RelationGetRelationName(rel));
/*
* And next write-lock the (current) right sibling.
*/
rightsib = opaque->btpo_next;
rbuf = _bt_getbuf(rel, rightsib, BT_WRITE);
/*
* Next find and write-lock the current parent of the target page. This is
* essentially the same as the corresponding step of splitting. However,
* it's possible for the search to fail (for reasons explained in README).
* If that happens, we recover by searching the whole parent level, which
* is a tad inefficient but doesn't happen often enough to be a problem.
*/
ItemPointerSet(&(stack->bts_btitem.bti_itup.t_tid),
target, P_HIKEY);
pbuf = _bt_getstackbuf(rel, stack, BT_WRITE);
if (pbuf == InvalidBuffer)
{
/* Find the leftmost page in the parent level */
pbuf = _bt_get_endpoint(rel, opaque->btpo.level + 1, false);
stack->bts_blkno = BufferGetBlockNumber(pbuf);
stack->bts_offset = InvalidOffsetNumber;
_bt_relbuf(rel, pbuf);
/* and repeat search from there */
pbuf = _bt_getstackbuf(rel, stack, BT_WRITE);
if (pbuf == InvalidBuffer)
elog(ERROR, "failed to re-find parent key in \"%s\" for deletion target page %u",
RelationGetRelationName(rel), target);
}
parent = stack->bts_blkno;
poffset = stack->bts_offset;
/*
* If the target is the rightmost child of its parent, then we can't
* delete, unless it's also the only child --- in which case the parent
* changes to half-dead status.
*/
page = BufferGetPage(pbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
maxoff = PageGetMaxOffsetNumber(page);
parent_half_dead = false;
parent_one_child = false;
if (poffset >= maxoff)
{
if (poffset == P_FIRSTDATAKEY(opaque))
parent_half_dead = true;
else
{
_bt_relbuf(rel, pbuf);
_bt_relbuf(rel, rbuf);
_bt_relbuf(rel, buf);
if (BufferIsValid(lbuf))
_bt_relbuf(rel, lbuf);
return 0;
}
}
else
{
/* Will there be exactly one child left in this parent? */
if (OffsetNumberNext(P_FIRSTDATAKEY(opaque)) == maxoff)
parent_one_child = true;
}
/*
* If we are deleting the next-to-last page on the target's level, then
* the rightsib is a candidate to become the new fast root. (In theory, it
* might be possible to push the fast root even further down, but the odds
* of doing so are slim, and the locking considerations daunting.)
*
* We can safely acquire a lock on the metapage here --- see comments for
* _bt_newroot().
*/
if (leftsib == P_NONE)
{
page = BufferGetPage(rbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
Assert(opaque->btpo.level == targetlevel);
if (P_RIGHTMOST(opaque))
{
/* rightsib will be the only one left on the level */
metabuf = _bt_getbuf(rel, BTREE_METAPAGE, BT_WRITE);
metapg = BufferGetPage(metabuf);
metad = BTPageGetMeta(metapg);
/*
* The expected case here is btm_fastlevel == targetlevel+1; if
* the fastlevel is <= targetlevel, something is wrong, and we
* choose to overwrite it to fix it.
*/
if (metad->btm_fastlevel > targetlevel + 1)
{
/* no update wanted */
_bt_relbuf(rel, metabuf);
metabuf = InvalidBuffer;
}
}
}
/*
* Here we begin doing the deletion.
*/
/* No ereport(ERROR) until changes are logged */
START_CRIT_SECTION();
/*
* Update parent. The normal case is a tad tricky because we want to
* delete the target's downlink and the *following* key. Easiest way is
* to copy the right sibling's downlink over the target downlink, and then
* delete the following item.
*/
page = BufferGetPage(pbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
if (parent_half_dead)
{
PageIndexTupleDelete(page, poffset);
opaque->btpo_flags |= BTP_HALF_DEAD;
}
else
{
OffsetNumber nextoffset;
itemid = PageGetItemId(page, poffset);
btitem = (BTItem) PageGetItem(page, itemid);
Assert(ItemPointerGetBlockNumber(&(btitem->bti_itup.t_tid)) == target);
ItemPointerSet(&(btitem->bti_itup.t_tid), rightsib, P_HIKEY);
nextoffset = OffsetNumberNext(poffset);
/* This part is just for double-checking */
itemid = PageGetItemId(page, nextoffset);
btitem = (BTItem) PageGetItem(page, itemid);
if (ItemPointerGetBlockNumber(&(btitem->bti_itup.t_tid)) != rightsib)
elog(PANIC, "right sibling is not next child in \"%s\"",
RelationGetRelationName(rel));
PageIndexTupleDelete(page, nextoffset);
}
/*
* Update siblings' side-links. Note the target page's side-links will
* continue to point to the siblings.
*/
if (BufferIsValid(lbuf))
{
page = BufferGetPage(lbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
Assert(opaque->btpo_next == target);
opaque->btpo_next = rightsib;
}
page = BufferGetPage(rbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
Assert(opaque->btpo_prev == target);
opaque->btpo_prev = leftsib;
rightsib_empty = (P_FIRSTDATAKEY(opaque) > PageGetMaxOffsetNumber(page));
/*
* Mark the page itself deleted. It can be recycled when all current
* transactions are gone; or immediately if we're doing VACUUM FULL.
*/
page = BufferGetPage(buf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
opaque->btpo_flags |= BTP_DELETED;
opaque->btpo.xact =
vacuum_full ? FrozenTransactionId : ReadNewTransactionId();
/* And update the metapage, if needed */
if (BufferIsValid(metabuf))
{
metad->btm_fastroot = rightsib;
metad->btm_fastlevel = targetlevel;
}
/* XLOG stuff */
if (!rel->rd_istemp)
{
xl_btree_delete_page xlrec;
xl_btree_metadata xlmeta;
uint8 xlinfo;
XLogRecPtr recptr;
XLogRecData rdata[5];
XLogRecData *nextrdata;
xlrec.target.node = rel->rd_node;
ItemPointerSet(&(xlrec.target.tid), parent, poffset);
xlrec.deadblk = target;
xlrec.leftblk = leftsib;
xlrec.rightblk = rightsib;
rdata[0].data = (char *) &xlrec;
rdata[0].len = SizeOfBtreeDeletePage;
rdata[0].buffer = InvalidBuffer;
rdata[0].next = nextrdata = &(rdata[1]);
if (BufferIsValid(metabuf))
{
xlmeta.root = metad->btm_root;
xlmeta.level = metad->btm_level;
xlmeta.fastroot = metad->btm_fastroot;
xlmeta.fastlevel = metad->btm_fastlevel;
nextrdata->data = (char *) &xlmeta;
nextrdata->len = sizeof(xl_btree_metadata);
nextrdata->buffer = InvalidBuffer;
nextrdata->next = nextrdata + 1;
nextrdata++;
xlinfo = XLOG_BTREE_DELETE_PAGE_META;
}
else
xlinfo = XLOG_BTREE_DELETE_PAGE;
nextrdata->data = NULL;
nextrdata->len = 0;
nextrdata->next = nextrdata + 1;
nextrdata->buffer = pbuf;
nextrdata->buffer_std = true;
nextrdata++;
nextrdata->data = NULL;
nextrdata->len = 0;
nextrdata->buffer = rbuf;
nextrdata->buffer_std = true;
nextrdata->next = NULL;
if (BufferIsValid(lbuf))
{
nextrdata->next = nextrdata + 1;
nextrdata++;
nextrdata->data = NULL;
nextrdata->len = 0;
nextrdata->buffer = lbuf;
nextrdata->buffer_std = true;
nextrdata->next = NULL;
}
recptr = XLogInsert(RM_BTREE_ID, xlinfo, rdata);
if (BufferIsValid(metabuf))
{
PageSetLSN(metapg, recptr);
PageSetTLI(metapg, ThisTimeLineID);
}
page = BufferGetPage(pbuf);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
page = BufferGetPage(rbuf);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
page = BufferGetPage(buf);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
if (BufferIsValid(lbuf))
{
page = BufferGetPage(lbuf);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
}
}
END_CRIT_SECTION();
/* Write and release buffers */
if (BufferIsValid(metabuf))
_bt_wrtbuf(rel, metabuf);
_bt_wrtbuf(rel, pbuf);
_bt_wrtbuf(rel, rbuf);
_bt_wrtbuf(rel, buf);
if (BufferIsValid(lbuf))
_bt_wrtbuf(rel, lbuf);
/*
* If parent became half dead, recurse to try to delete it. Otherwise, if
* right sibling is empty and is now the last child of the parent, recurse
* to try to delete it. (These cases cannot apply at the same time,
* though the second case might itself recurse to the first.)
*/
if (parent_half_dead)
{
buf = _bt_getbuf(rel, parent, BT_READ);
return _bt_pagedel(rel, buf, vacuum_full) + 1;
}
if (parent_one_child && rightsib_empty)
{
buf = _bt_getbuf(rel, rightsib, BT_READ);
return _bt_pagedel(rel, buf, vacuum_full) + 1;
}
return 1;
}
/*
* _bt_getroot() -- Get the root page of the btree.
*
* Since the root page can move around the btree file, we have to read
* its location from the metadata page, and then read the root page
* itself. If no root page exists yet, we have to create one. The
* standard class of race conditions exists here; I think I covered
* them all in the Hopi Indian rain dance of lock requests below.
*
* The access type parameter (BT_READ or BT_WRITE) controls whether
* a new root page will be created or not. If access = BT_READ,
* and no root page exists, we just return InvalidBuffer. For
* BT_WRITE, we try to create the root page if it doesn't exist.
* NOTE that the returned root page will have only a read lock set
* on it even if access = BT_WRITE!
*
* The returned page is not necessarily the true root --- it could be
* a "fast root" (a page that is alone in its level due to deletions).
* Also, if the root page is split while we are "in flight" to it,
* what we will return is the old root, which is now just the leftmost
* page on a probably-not-very-wide level. For most purposes this is
* as good as or better than the true root, so we do not bother to
* insist on finding the true root. We do, however, guarantee to
* return a live (not deleted or half-dead) page.
*
* On successful return, the root page is pinned and read-locked.
* The metadata page is not locked or pinned on exit.
*/
Buffer
_bt_getroot(Relation rel, int access)
{
Buffer metabuf;
Page metapg;
BTPageOpaque metaopaque;
Buffer rootbuf;
Page rootpage;
BTPageOpaque rootopaque;
BlockNumber rootblkno;
uint32 rootlevel;
BTMetaPageData *metad;
metabuf = _bt_getbuf(rel, BTREE_METAPAGE, BT_READ);
metapg = BufferGetPage(metabuf);
metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg);
metad = BTPageGetMeta(metapg);
/* sanity-check the metapage */
if (!(metaopaque->btpo_flags & BTP_META) ||
metad->btm_magic != BTREE_MAGIC)
ereport(ERROR,
(errcode(ERRCODE_INDEX_CORRUPTED),
errmsg("index \"%s\" is not a btree",
RelationGetRelationName(rel))));
if (metad->btm_version != BTREE_VERSION)
ereport(ERROR,
(errcode(ERRCODE_INDEX_CORRUPTED),
errmsg("version mismatch in index \"%s\": file version %d, code version %d",
RelationGetRelationName(rel),
metad->btm_version, BTREE_VERSION)));
/* if no root page initialized yet, do it */
if (metad->btm_root == P_NONE)
{
/* If access = BT_READ, caller doesn't want us to create root yet */
if (access == BT_READ)
{
_bt_relbuf(rel, metabuf);
return InvalidBuffer;
}
/* trade in our read lock for a write lock */
LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
LockBuffer(metabuf, BT_WRITE);
/*
* Race condition: if someone else initialized the metadata between
* the time we released the read lock and acquired the write lock, we
* must avoid doing it again.
*/
if (metad->btm_root != P_NONE)
{
/*
* Metadata initialized by someone else. In order to guarantee no
* deadlocks, we have to release the metadata page and start all
* over again. (Is that really true? But it's hardly worth trying
* to optimize this case.)
*/
_bt_relbuf(rel, metabuf);
return _bt_getroot(rel, access);
}
/*
* Get, initialize, write, and leave a lock of the appropriate type on
* the new root page. Since this is the first page in the tree, it's
* a leaf as well as the root.
*/
rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE);
rootblkno = BufferGetBlockNumber(rootbuf);
rootpage = BufferGetPage(rootbuf);
_bt_pageinit(rootpage, BufferGetPageSize(rootbuf));
rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage);
rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE;
rootopaque->btpo_flags = (BTP_LEAF | BTP_ROOT);
rootopaque->btpo.level = 0;
/* NO ELOG(ERROR) till meta is updated */
START_CRIT_SECTION();
metad->btm_root = rootblkno;
metad->btm_level = 0;
metad->btm_fastroot = rootblkno;
metad->btm_fastlevel = 0;
/* XLOG stuff */
if (!rel->rd_istemp)
{
xl_btree_newroot xlrec;
XLogRecPtr recptr;
XLogRecData rdata;
xlrec.node = rel->rd_node;
xlrec.rootblk = rootblkno;
xlrec.level = 0;
rdata.data = (char *) &xlrec;
rdata.len = SizeOfBtreeNewroot;
rdata.buffer = InvalidBuffer;
rdata.next = NULL;
recptr = XLogInsert(RM_BTREE_ID, XLOG_BTREE_NEWROOT, &rdata);
PageSetLSN(rootpage, recptr);
PageSetTLI(rootpage, ThisTimeLineID);
PageSetLSN(metapg, recptr);
PageSetTLI(metapg, ThisTimeLineID);
}
END_CRIT_SECTION();
_bt_wrtnorelbuf(rel, rootbuf);
/*
* swap root write lock for read lock. There is no danger of anyone
* else accessing the new root page while it's unlocked, since no one
* else knows where it is yet.
*/
LockBuffer(rootbuf, BUFFER_LOCK_UNLOCK);
LockBuffer(rootbuf, BT_READ);
/* okay, metadata is correct, write and release it */
_bt_wrtbuf(rel, metabuf);
}
else
{
rootblkno = metad->btm_fastroot;
Assert(rootblkno != P_NONE);
rootlevel = metad->btm_fastlevel;
/*
* We are done with the metapage; arrange to release it via first
* _bt_relandgetbuf call
*/
rootbuf = metabuf;
for (;;)
{
rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ);
rootpage = BufferGetPage(rootbuf);
rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage);
if (!P_IGNORE(rootopaque))
break;
/* it's dead, Jim. step right one page */
if (P_RIGHTMOST(rootopaque))
elog(ERROR, "no live root page found in \"%s\"",
RelationGetRelationName(rel));
rootblkno = rootopaque->btpo_next;
}
/* Note: can't check btpo.level on deleted pages */
if (rootopaque->btpo.level != rootlevel)
elog(ERROR, "root page %u of \"%s\" has level %u, expected %u",
rootblkno, RelationGetRelationName(rel),
rootopaque->btpo.level, rootlevel);
}
/*
* By here, we have a pin and read lock on the root page, and no lock set
* on the metadata page. Return the root page's buffer.
*/
return rootbuf;
}
/*
* Drop a table space
*
* Be careful to check that the tablespace is empty.
*/
void
DropTableSpace(DropTableSpaceStmt *stmt)
{
#ifdef HAVE_SYMLINK
char *tablespacename = stmt->tablespacename;
HeapScanDesc scandesc;
Relation rel;
HeapTuple tuple;
ScanKeyData entry[1];
Oid tablespaceoid;
/* don't call this in a transaction block */
PreventTransactionChain((void *) stmt, "DROP TABLESPACE");
/*
* Acquire ExclusiveLock on pg_tablespace to ensure that no one else is
* trying to do DROP TABLESPACE or TablespaceCreateDbspace concurrently.
*/
rel = heap_open(TableSpaceRelationId, ExclusiveLock);
/*
* Find the target tuple
*/
ScanKeyInit(&entry[0],
Anum_pg_tablespace_spcname,
BTEqualStrategyNumber, F_NAMEEQ,
CStringGetDatum(tablespacename));
scandesc = heap_beginscan(rel, SnapshotNow, 1, entry);
tuple = heap_getnext(scandesc, ForwardScanDirection);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("tablespace \"%s\" does not exist",
tablespacename)));
tablespaceoid = HeapTupleGetOid(tuple);
/* Must be tablespace owner */
if (!pg_tablespace_ownercheck(tablespaceoid, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_TABLESPACE,
tablespacename);
/* Disallow drop of the standard tablespaces, even by superuser */
if (tablespaceoid == GLOBALTABLESPACE_OID ||
tablespaceoid == DEFAULTTABLESPACE_OID)
aclcheck_error(ACLCHECK_NO_PRIV, ACL_KIND_TABLESPACE,
tablespacename);
/*
* Remove the pg_tablespace tuple (this will roll back if we fail below)
*/
simple_heap_delete(rel, &tuple->t_self);
heap_endscan(scandesc);
/*
* Remove dependency on owner.
*/
deleteSharedDependencyRecordsFor(TableSpaceRelationId, tablespaceoid);
/*
* Try to remove the physical infrastructure
*/
if (!remove_tablespace_directories(tablespaceoid, false))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("tablespace \"%s\" is not empty",
tablespacename)));
/* Record the filesystem change in XLOG */
{
xl_tblspc_drop_rec xlrec;
XLogRecData rdata[1];
xlrec.ts_id = tablespaceoid;
rdata[0].data = (char *) &xlrec;
rdata[0].len = sizeof(xl_tblspc_drop_rec);
rdata[0].buffer = InvalidBuffer;
rdata[0].next = NULL;
(void) XLogInsert(RM_TBLSPC_ID, XLOG_TBLSPC_DROP, rdata);
}
/* We keep the lock on pg_tablespace until commit */
heap_close(rel, NoLock);
#else /* !HAVE_SYMLINK */
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("tablespaces are not supported on this platform")));
#endif /* HAVE_SYMLINK */
}
/*
* Insert value (stored in GinBtree) to tree described by stack
*/
void
ginInsertValue(GinBtree btree, GinBtreeStack *stack)
{
GinBtreeStack *parent = stack;
BlockNumber rootBlkno = InvalidBuffer;
Page page,
rpage,
lpage;
/* remember root BlockNumber */
while (parent)
{
rootBlkno = parent->blkno;
parent = parent->parent;
}
while (stack)
{
XLogRecData *rdata;
BlockNumber savedRightLink;
page = BufferGetPage(stack->buffer);
savedRightLink = GinPageGetOpaque(page)->rightlink;
if (btree->isEnoughSpace(btree, stack->buffer, stack->off))
{
START_CRIT_SECTION();
btree->placeToPage(btree, stack->buffer, stack->off, &rdata);
MarkBufferDirty(stack->buffer);
if (!btree->index->rd_istemp)
{
XLogRecPtr recptr;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_INSERT, rdata);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
}
UnlockReleaseBuffer(stack->buffer);
END_CRIT_SECTION();
freeGinBtreeStack(stack->parent);
return;
}
else
{
Buffer rbuffer = GinNewBuffer(btree->index);
Page newlpage;
/*
* newlpage is a pointer to memory page, it doesn't associate with
* buffer, stack->buffer should be untouched
*/
newlpage = btree->splitPage(btree, stack->buffer, rbuffer, stack->off, &rdata);
((ginxlogSplit *) (rdata->data))->rootBlkno = rootBlkno;
parent = stack->parent;
if (parent == NULL)
{
/*
* split root, so we need to allocate new left page and place
* pointer on root to left and right page
*/
Buffer lbuffer = GinNewBuffer(btree->index);
((ginxlogSplit *) (rdata->data))->isRootSplit = TRUE;
((ginxlogSplit *) (rdata->data))->rrlink = InvalidBlockNumber;
page = BufferGetPage(stack->buffer);
lpage = BufferGetPage(lbuffer);
rpage = BufferGetPage(rbuffer);
GinPageGetOpaque(rpage)->rightlink = InvalidBlockNumber;
GinPageGetOpaque(newlpage)->rightlink = BufferGetBlockNumber(rbuffer);
((ginxlogSplit *) (rdata->data))->lblkno = BufferGetBlockNumber(lbuffer);
START_CRIT_SECTION();
GinInitBuffer(stack->buffer, GinPageGetOpaque(newlpage)->flags & ~GIN_LEAF);
PageRestoreTempPage(newlpage, lpage);
btree->fillRoot(btree, stack->buffer, lbuffer, rbuffer);
MarkBufferDirty(rbuffer);
MarkBufferDirty(lbuffer);
MarkBufferDirty(stack->buffer);
if (!btree->index->rd_istemp)
{
XLogRecPtr recptr;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_SPLIT, rdata);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
PageSetLSN(lpage, recptr);
PageSetTLI(lpage, ThisTimeLineID);
PageSetLSN(rpage, recptr);
PageSetTLI(rpage, ThisTimeLineID);
}
UnlockReleaseBuffer(rbuffer);
UnlockReleaseBuffer(lbuffer);
UnlockReleaseBuffer(stack->buffer);
END_CRIT_SECTION();
return;
}
else
{
/* split non-root page */
((ginxlogSplit *) (rdata->data))->isRootSplit = FALSE;
((ginxlogSplit *) (rdata->data))->rrlink = savedRightLink;
lpage = BufferGetPage(stack->buffer);
rpage = BufferGetPage(rbuffer);
GinPageGetOpaque(rpage)->rightlink = savedRightLink;
GinPageGetOpaque(newlpage)->rightlink = BufferGetBlockNumber(rbuffer);
START_CRIT_SECTION();
PageRestoreTempPage(newlpage, lpage);
MarkBufferDirty(rbuffer);
MarkBufferDirty(stack->buffer);
if (!btree->index->rd_istemp)
{
XLogRecPtr recptr;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_SPLIT, rdata);
PageSetLSN(lpage, recptr);
PageSetTLI(lpage, ThisTimeLineID);
PageSetLSN(rpage, recptr);
PageSetTLI(rpage, ThisTimeLineID);
}
UnlockReleaseBuffer(rbuffer);
END_CRIT_SECTION();
}
}
btree->isDelete = FALSE;
/* search parent to lock */
LockBuffer(parent->buffer, GIN_EXCLUSIVE);
/* move right if it's needed */
page = BufferGetPage(parent->buffer);
while ((parent->off = btree->findChildPtr(btree, page, stack->blkno, parent->off)) == InvalidOffsetNumber)
{
BlockNumber rightlink = GinPageGetOpaque(page)->rightlink;
LockBuffer(parent->buffer, GIN_UNLOCK);
if (rightlink == InvalidBlockNumber)
{
/*
* rightmost page, but we don't find parent, we should use
* plain search...
*/
findParents(btree, stack, rootBlkno);
parent = stack->parent;
page = BufferGetPage(parent->buffer);
break;
}
parent->blkno = rightlink;
parent->buffer = ReleaseAndReadBuffer(parent->buffer, btree->index, parent->blkno);
LockBuffer(parent->buffer, GIN_EXCLUSIVE);
page = BufferGetPage(parent->buffer);
}
UnlockReleaseBuffer(stack->buffer);
pfree(stack);
stack = parent;
}
}
/*
* Insert an index tuple into the index relation. The revmap is updated to
* mark the range containing the given page as pointing to the inserted entry.
* A WAL record is written.
*
* The buffer, if valid, is first checked for free space to insert the new
* entry; if there isn't enough, a new buffer is obtained and pinned. No
* buffer lock must be held on entry, no buffer lock is held on exit.
*
* Return value is the offset number where the tuple was inserted.
*/
OffsetNumber
brin_doinsert(Relation idxrel, BlockNumber pagesPerRange,
BrinRevmap *revmap, Buffer *buffer, BlockNumber heapBlk,
BrinTuple *tup, Size itemsz)
{
Page page;
BlockNumber blk;
OffsetNumber off;
Buffer revmapbuf;
ItemPointerData tid;
bool extended;
Assert(itemsz == MAXALIGN(itemsz));
/* If the item is oversized, don't even bother. */
if (itemsz > BrinMaxItemSize)
{
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("index row size %lu exceeds maximum %lu for index \"%s\"",
(unsigned long) itemsz,
(unsigned long) BrinMaxItemSize,
RelationGetRelationName(idxrel))));
return InvalidOffsetNumber; /* keep compiler quiet */
}
/* Make sure the revmap is long enough to contain the entry we need */
brinRevmapExtend(revmap, heapBlk);
/*
* Acquire lock on buffer supplied by caller, if any. If it doesn't have
* enough space, unpin it to obtain a new one below.
*/
if (BufferIsValid(*buffer))
{
/*
* It's possible that another backend (or ourselves!) extended the
* revmap over the page we held a pin on, so we cannot assume that
* it's still a regular page.
*/
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
if (br_page_get_freespace(BufferGetPage(*buffer)) < itemsz)
{
UnlockReleaseBuffer(*buffer);
*buffer = InvalidBuffer;
}
}
/*
* If we still don't have a usable buffer, have brin_getinsertbuffer
* obtain one for us.
*/
if (!BufferIsValid(*buffer))
{
do
*buffer = brin_getinsertbuffer(idxrel, InvalidBuffer, itemsz, &extended);
while (!BufferIsValid(*buffer));
}
else
extended = false;
/* Now obtain lock on revmap buffer */
revmapbuf = brinLockRevmapPageForUpdate(revmap, heapBlk);
page = BufferGetPage(*buffer);
blk = BufferGetBlockNumber(*buffer);
/* Execute the actual insertion */
START_CRIT_SECTION();
if (extended)
brin_page_init(BufferGetPage(*buffer), BRIN_PAGETYPE_REGULAR);
off = PageAddItem(page, (Item) tup, itemsz, InvalidOffsetNumber,
false, false);
if (off == InvalidOffsetNumber)
elog(ERROR, "could not insert new index tuple to page");
MarkBufferDirty(*buffer);
BRIN_elog((DEBUG2, "inserted tuple (%u,%u) for range starting at %u",
blk, off, heapBlk));
ItemPointerSet(&tid, blk, off);
brinSetHeapBlockItemptr(revmapbuf, pagesPerRange, heapBlk, tid);
MarkBufferDirty(revmapbuf);
/* XLOG stuff */
if (RelationNeedsWAL(idxrel))
{
xl_brin_insert xlrec;
XLogRecPtr recptr;
uint8 info;
info = XLOG_BRIN_INSERT | (extended ? XLOG_BRIN_INIT_PAGE : 0);
xlrec.heapBlk = heapBlk;
xlrec.pagesPerRange = pagesPerRange;
xlrec.offnum = off;
XLogBeginInsert();
XLogRegisterData((char *) &xlrec, SizeOfBrinInsert);
XLogRegisterBuffer(0, *buffer, REGBUF_STANDARD | (extended ? REGBUF_WILL_INIT : 0));
XLogRegisterBufData(0, (char *) tup, itemsz);
XLogRegisterBuffer(1, revmapbuf, 0);
recptr = XLogInsert(RM_BRIN_ID, info);
PageSetLSN(page, recptr);
PageSetLSN(BufferGetPage(revmapbuf), recptr);
}
END_CRIT_SECTION();
/* Tuple is firmly on buffer; we can release our locks */
LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
LockBuffer(revmapbuf, BUFFER_LOCK_UNLOCK);
if (extended)
FreeSpaceMapVacuum(idxrel);
return off;
}
/*
* Write a backup block if needed when we are setting a hint. Note that
* this may be called for a variety of page types, not just heaps.
*
* Callable while holding just share lock on the buffer content.
*
* We can't use the plain backup block mechanism since that relies on the
* Buffer being exclusively locked. Since some modifications (setting LSN, hint
* bits) are allowed in a sharelocked buffer that can lead to wal checksum
* failures. So instead we copy the page and insert the copied data as normal
* record data.
*
* We only need to do something if page has not yet been full page written in
* this checkpoint round. The LSN of the inserted wal record is returned if we
* had to write, InvalidXLogRecPtr otherwise.
*
* It is possible that multiple concurrent backends could attempt to write WAL
* records. In that case, multiple copies of the same block would be recorded
* in separate WAL records by different backends, though that is still OK from
* a correctness perspective.
*/
XLogRecPtr
XLogSaveBufferForHint(Buffer buffer, bool buffer_std)
{
XLogRecPtr recptr = InvalidXLogRecPtr;
XLogRecPtr lsn;
XLogRecPtr RedoRecPtr;
/*
* Ensure no checkpoint can change our view of RedoRecPtr.
*/
Assert(MyPgXact->delayChkpt);
/*
* Update RedoRecPtr so that we can make the right decision
*/
RedoRecPtr = GetRedoRecPtr();
/*
* We assume page LSN is first data on *every* page that can be passed to
* XLogInsert, whether it has the standard page layout or not. Since we're
* only holding a share-lock on the page, we must take the buffer header
* lock when we look at the LSN.
*/
lsn = BufferGetLSNAtomic(buffer);
if (lsn <= RedoRecPtr)
{
int flags;
PGAlignedBlock copied_buffer;
char *origdata = (char *) BufferGetBlock(buffer);
RelFileNode rnode;
ForkNumber forkno;
BlockNumber blkno;
/*
* Copy buffer so we don't have to worry about concurrent hint bit or
* lsn updates. We assume pd_lower/upper cannot be changed without an
* exclusive lock, so the contents bkp are not racy.
*/
if (buffer_std)
{
/* Assume we can omit data between pd_lower and pd_upper */
Page page = BufferGetPage(buffer);
uint16 lower = ((PageHeader) page)->pd_lower;
uint16 upper = ((PageHeader) page)->pd_upper;
memcpy(copied_buffer.data, origdata, lower);
memcpy(copied_buffer.data + upper, origdata + upper, BLCKSZ - upper);
}
else
memcpy(copied_buffer.data, origdata, BLCKSZ);
XLogBeginInsert();
flags = REGBUF_FORCE_IMAGE;
if (buffer_std)
flags |= REGBUF_STANDARD;
BufferGetTag(buffer, &rnode, &forkno, &blkno);
XLogRegisterBlock(0, &rnode, forkno, blkno, copied_buffer.data, flags);
recptr = XLogInsert(RM_XLOG_ID, XLOG_FPI_FOR_HINT);
}
return recptr;
}
/*
* Update tuple origtup (size origsz), located in offset oldoff of buffer
* oldbuf, to newtup (size newsz) as summary tuple for the page range starting
* at heapBlk. oldbuf must not be locked on entry, and is not locked at exit.
*
* If samepage is true, attempt to put the new tuple in the same page, but if
* there's no room, use some other one.
*
* If the update is successful, return true; the revmap is updated to point to
* the new tuple. If the update is not done for whatever reason, return false.
* Caller may retry the update if this happens.
*/
bool
brin_doupdate(Relation idxrel, BlockNumber pagesPerRange,
BrinRevmap *revmap, BlockNumber heapBlk,
Buffer oldbuf, OffsetNumber oldoff,
const BrinTuple *origtup, Size origsz,
const BrinTuple *newtup, Size newsz,
bool samepage)
{
Page oldpage;
ItemId oldlp;
BrinTuple *oldtup;
Size oldsz;
Buffer newbuf;
bool extended;
Assert(newsz == MAXALIGN(newsz));
/* If the item is oversized, don't bother. */
if (newsz > BrinMaxItemSize)
{
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("index row size %lu exceeds maximum %lu for index \"%s\"",
(unsigned long) newsz,
(unsigned long) BrinMaxItemSize,
RelationGetRelationName(idxrel))));
return false; /* keep compiler quiet */
}
/* make sure the revmap is long enough to contain the entry we need */
brinRevmapExtend(revmap, heapBlk);
if (!samepage)
{
/* need a page on which to put the item */
newbuf = brin_getinsertbuffer(idxrel, oldbuf, newsz, &extended);
if (!BufferIsValid(newbuf))
{
Assert(!extended);
return false;
}
/*
* Note: it's possible (though unlikely) that the returned newbuf is
* the same as oldbuf, if brin_getinsertbuffer determined that the old
* buffer does in fact have enough space.
*/
if (newbuf == oldbuf)
{
Assert(!extended);
newbuf = InvalidBuffer;
}
}
else
{
LockBuffer(oldbuf, BUFFER_LOCK_EXCLUSIVE);
newbuf = InvalidBuffer;
extended = false;
}
oldpage = BufferGetPage(oldbuf);
oldlp = PageGetItemId(oldpage, oldoff);
/*
* Check that the old tuple wasn't updated concurrently: it might have
* moved someplace else entirely ...
*/
if (!ItemIdIsNormal(oldlp))
{
LockBuffer(oldbuf, BUFFER_LOCK_UNLOCK);
/*
* If this happens, and the new buffer was obtained by extending the
* relation, then we need to ensure we don't leave it uninitialized or
* forget about it.
*/
if (BufferIsValid(newbuf))
{
if (extended)
brin_initialize_empty_new_buffer(idxrel, newbuf);
UnlockReleaseBuffer(newbuf);
if (extended)
FreeSpaceMapVacuum(idxrel);
}
return false;
}
oldsz = ItemIdGetLength(oldlp);
oldtup = (BrinTuple *) PageGetItem(oldpage, oldlp);
/*
* ... or it might have been updated in place to different contents.
*/
if (!brin_tuples_equal(oldtup, oldsz, origtup, origsz))
{
LockBuffer(oldbuf, BUFFER_LOCK_UNLOCK);
if (BufferIsValid(newbuf))
{
if (extended)
brin_initialize_empty_new_buffer(idxrel, newbuf);
UnlockReleaseBuffer(newbuf);
if (extended)
FreeSpaceMapVacuum(idxrel);
}
return false;
}
/*
* Great, the old tuple is intact. We can proceed with the update.
*
* If there's enough room in the old page for the new tuple, replace it.
*
* Note that there might now be enough space on the page even though the
* caller told us there isn't, if a concurrent update moved another tuple
* elsewhere or replaced a tuple with a smaller one.
*/
if (((BrinPageFlags(oldpage) & BRIN_EVACUATE_PAGE) == 0) &&
brin_can_do_samepage_update(oldbuf, origsz, newsz))
{
if (BufferIsValid(newbuf))
{
/* as above */
if (extended)
brin_initialize_empty_new_buffer(idxrel, newbuf);
UnlockReleaseBuffer(newbuf);
}
START_CRIT_SECTION();
if (!PageIndexTupleOverwrite(oldpage, oldoff, (Item) newtup, newsz))
elog(ERROR, "failed to replace BRIN tuple");
MarkBufferDirty(oldbuf);
/* XLOG stuff */
if (RelationNeedsWAL(idxrel))
{
xl_brin_samepage_update xlrec;
XLogRecPtr recptr;
uint8 info = XLOG_BRIN_SAMEPAGE_UPDATE;
xlrec.offnum = oldoff;
XLogBeginInsert();
XLogRegisterData((char *) &xlrec, SizeOfBrinSamepageUpdate);
XLogRegisterBuffer(0, oldbuf, REGBUF_STANDARD);
XLogRegisterBufData(0, (char *) newtup, newsz);
recptr = XLogInsert(RM_BRIN_ID, info);
PageSetLSN(oldpage, recptr);
}
END_CRIT_SECTION();
LockBuffer(oldbuf, BUFFER_LOCK_UNLOCK);
if (extended)
FreeSpaceMapVacuum(idxrel);
return true;
}
else if (newbuf == InvalidBuffer)
{
/*
* Not enough space, but caller said that there was. Tell them to
* start over.
*/
LockBuffer(oldbuf, BUFFER_LOCK_UNLOCK);
return false;
}
else
{
/*
* Not enough free space on the oldpage. Put the new tuple on the new
* page, and update the revmap.
*/
Page newpage = BufferGetPage(newbuf);
Buffer revmapbuf;
ItemPointerData newtid;
OffsetNumber newoff;
BlockNumber newblk = InvalidBlockNumber;
Size freespace = 0;
revmapbuf = brinLockRevmapPageForUpdate(revmap, heapBlk);
START_CRIT_SECTION();
/*
* We need to initialize the page if it's newly obtained. Note we
* will WAL-log the initialization as part of the update, so we don't
* need to do that here.
*/
if (extended)
brin_page_init(BufferGetPage(newbuf), BRIN_PAGETYPE_REGULAR);
PageIndexTupleDeleteNoCompact(oldpage, oldoff);
newoff = PageAddItem(newpage, (Item) newtup, newsz,
InvalidOffsetNumber, false, false);
if (newoff == InvalidOffsetNumber)
elog(ERROR, "failed to add BRIN tuple to new page");
MarkBufferDirty(oldbuf);
MarkBufferDirty(newbuf);
/* needed to update FSM below */
if (extended)
{
newblk = BufferGetBlockNumber(newbuf);
freespace = br_page_get_freespace(newpage);
}
ItemPointerSet(&newtid, BufferGetBlockNumber(newbuf), newoff);
brinSetHeapBlockItemptr(revmapbuf, pagesPerRange, heapBlk, newtid);
MarkBufferDirty(revmapbuf);
/* XLOG stuff */
if (RelationNeedsWAL(idxrel))
{
xl_brin_update xlrec;
XLogRecPtr recptr;
uint8 info;
info = XLOG_BRIN_UPDATE | (extended ? XLOG_BRIN_INIT_PAGE : 0);
xlrec.insert.offnum = newoff;
xlrec.insert.heapBlk = heapBlk;
xlrec.insert.pagesPerRange = pagesPerRange;
xlrec.oldOffnum = oldoff;
XLogBeginInsert();
/* new page */
XLogRegisterData((char *) &xlrec, SizeOfBrinUpdate);
XLogRegisterBuffer(0, newbuf, REGBUF_STANDARD | (extended ? REGBUF_WILL_INIT : 0));
XLogRegisterBufData(0, (char *) newtup, newsz);
/* revmap page */
XLogRegisterBuffer(1, revmapbuf, 0);
/* old page */
XLogRegisterBuffer(2, oldbuf, REGBUF_STANDARD);
recptr = XLogInsert(RM_BRIN_ID, info);
PageSetLSN(oldpage, recptr);
PageSetLSN(newpage, recptr);
PageSetLSN(BufferGetPage(revmapbuf), recptr);
}
END_CRIT_SECTION();
LockBuffer(revmapbuf, BUFFER_LOCK_UNLOCK);
LockBuffer(oldbuf, BUFFER_LOCK_UNLOCK);
UnlockReleaseBuffer(newbuf);
if (extended)
{
Assert(BlockNumberIsValid(newblk));
RecordPageWithFreeSpace(idxrel, newblk, freespace);
FreeSpaceMapVacuum(idxrel);
}
return true;
}
}
static void
ginDeletePage(GinVacuumState *gvs, BlockNumber deleteBlkno, BlockNumber leftBlkno,
BlockNumber parentBlkno, OffsetNumber myoff, bool isParentRoot)
{
Buffer dBuffer;
Buffer lBuffer;
Buffer pBuffer;
Page page,
parentPage;
dBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, deleteBlkno,
RBM_NORMAL, gvs->strategy);
if (leftBlkno != InvalidBlockNumber)
lBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, leftBlkno,
RBM_NORMAL, gvs->strategy);
else
lBuffer = InvalidBuffer;
pBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, parentBlkno,
RBM_NORMAL, gvs->strategy);
LockBuffer(dBuffer, GIN_EXCLUSIVE);
if (!isParentRoot) /* parent is already locked by
* LockBufferForCleanup() */
LockBuffer(pBuffer, GIN_EXCLUSIVE);
if (leftBlkno != InvalidBlockNumber)
LockBuffer(lBuffer, GIN_EXCLUSIVE);
START_CRIT_SECTION();
if (leftBlkno != InvalidBlockNumber)
{
BlockNumber rightlink;
page = BufferGetPage(dBuffer);
rightlink = GinPageGetOpaque(page)->rightlink;
page = BufferGetPage(lBuffer);
GinPageGetOpaque(page)->rightlink = rightlink;
}
parentPage = BufferGetPage(pBuffer);
#ifdef USE_ASSERT_CHECKING
do
{
PostingItem *tod = (PostingItem *) GinDataPageGetItem(parentPage, myoff);
Assert(PostingItemGetBlockNumber(tod) == deleteBlkno);
} while (0);
#endif
PageDeletePostingItem(parentPage, myoff);
page = BufferGetPage(dBuffer);
/*
* we shouldn't change rightlink field to save workability of running
* search scan
*/
GinPageGetOpaque(page)->flags = GIN_DELETED;
MarkBufferDirty(pBuffer);
if (leftBlkno != InvalidBlockNumber)
MarkBufferDirty(lBuffer);
MarkBufferDirty(dBuffer);
if (!gvs->index->rd_istemp)
{
XLogRecPtr recptr;
XLogRecData rdata[4];
ginxlogDeletePage data;
int n;
data.node = gvs->index->rd_node;
data.blkno = deleteBlkno;
data.parentBlkno = parentBlkno;
data.parentOffset = myoff;
data.leftBlkno = leftBlkno;
data.rightLink = GinPageGetOpaque(page)->rightlink;
rdata[0].buffer = dBuffer;
rdata[0].buffer_std = FALSE;
rdata[0].data = NULL;
rdata[0].len = 0;
rdata[0].next = rdata + 1;
rdata[1].buffer = pBuffer;
rdata[1].buffer_std = FALSE;
rdata[1].data = NULL;
rdata[1].len = 0;
rdata[1].next = rdata + 2;
if (leftBlkno != InvalidBlockNumber)
{
rdata[2].buffer = lBuffer;
rdata[2].buffer_std = FALSE;
rdata[2].data = NULL;
rdata[2].len = 0;
rdata[2].next = rdata + 3;
n = 3;
}
else
n = 2;
rdata[n].buffer = InvalidBuffer;
rdata[n].buffer_std = FALSE;
rdata[n].len = sizeof(ginxlogDeletePage);
rdata[n].data = (char *) &data;
rdata[n].next = NULL;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_DELETE_PAGE, rdata);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
PageSetLSN(parentPage, recptr);
PageSetTLI(parentPage, ThisTimeLineID);
if (leftBlkno != InvalidBlockNumber)
{
page = BufferGetPage(lBuffer);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
}
}
if (!isParentRoot)
LockBuffer(pBuffer, GIN_UNLOCK);
ReleaseBuffer(pBuffer);
if (leftBlkno != InvalidBlockNumber)
UnlockReleaseBuffer(lBuffer);
UnlockReleaseBuffer(dBuffer);
END_CRIT_SECTION();
gvs->result->pages_deleted++;
}
static bool
gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
{
bool is_splitted = false;
bool is_leaf = (GistPageIsLeaf(state->stack->page)) ? true : false;
MIRROREDLOCK_BUFMGR_MUST_ALREADY_BE_HELD;
/*
* if (!is_leaf) remove old key: This node's key has been modified, either
* because a child split occurred or because we needed to adjust our key
* for an insert in a child node. Therefore, remove the old version of
* this node's key.
*
* for WAL replay, in the non-split case we handle this by setting up a
* one-element todelete array; in the split case, it's handled implicitly
* because the tuple vector passed to gistSplit won't include this tuple.
*
* XXX: If we want to change fillfactors between node and leaf, fillfactor
* = (is_leaf ? state->leaf_fillfactor : state->node_fillfactor)
*/
if (gistnospace(state->stack->page, state->itup, state->ituplen,
is_leaf ? InvalidOffsetNumber : state->stack->childoffnum,
state->freespace))
{
/* no space for insertion */
IndexTuple *itvec;
int tlen;
SplitedPageLayout *dist = NULL,
*ptr;
BlockNumber rrlink = InvalidBlockNumber;
GistNSN oldnsn;
is_splitted = true;
/*
* Form index tuples vector to split: remove old tuple if t's needed
* and add new tuples to vector
*/
itvec = gistextractpage(state->stack->page, &tlen);
if (!is_leaf)
{
/* on inner page we should remove old tuple */
int pos = state->stack->childoffnum - FirstOffsetNumber;
tlen--;
if (pos != tlen)
memmove(itvec + pos, itvec + pos + 1, sizeof(IndexTuple) * (tlen - pos));
}
itvec = gistjoinvector(itvec, &tlen, state->itup, state->ituplen);
dist = gistSplit(state->r, state->stack->page, itvec, tlen, giststate);
state->itup = (IndexTuple *) palloc(sizeof(IndexTuple) * tlen);
state->ituplen = 0;
if (state->stack->blkno != GIST_ROOT_BLKNO)
{
/*
* if non-root split then we should not allocate new buffer, but
* we must create temporary page to operate
*/
dist->buffer = state->stack->buffer;
dist->page = PageGetTempPage(BufferGetPage(dist->buffer), sizeof(GISTPageOpaqueData));
/* clean all flags except F_LEAF */
GistPageGetOpaque(dist->page)->flags = (is_leaf) ? F_LEAF : 0;
}
/* make new pages and fills them */
for (ptr = dist; ptr; ptr = ptr->next)
{
int i;
char *data;
/* get new page */
if (ptr->buffer == InvalidBuffer)
{
ptr->buffer = gistNewBuffer(state->r);
GISTInitBuffer(ptr->buffer, (is_leaf) ? F_LEAF : 0);
ptr->page = BufferGetPage(ptr->buffer);
}
ptr->block.blkno = BufferGetBlockNumber(ptr->buffer);
/*
* fill page, we can do it because all these pages are new
* (ie not linked in tree or masked by temp page
*/
data = (char *) (ptr->list);
for (i = 0; i < ptr->block.num; i++)
{
if (PageAddItem(ptr->page, (Item) data, IndexTupleSize((IndexTuple) data), i + FirstOffsetNumber, LP_USED) == InvalidOffsetNumber)
elog(ERROR, "failed to add item to index page in \"%s\"", RelationGetRelationName(state->r));
data += IndexTupleSize((IndexTuple) data);
}
/* set up ItemPointer and remember it for parent */
ItemPointerSetBlockNumber(&(ptr->itup->t_tid), ptr->block.blkno);
state->itup[state->ituplen] = ptr->itup;
state->ituplen++;
}
/* saves old rightlink */
if (state->stack->blkno != GIST_ROOT_BLKNO)
rrlink = GistPageGetOpaque(dist->page)->rightlink;
START_CRIT_SECTION();
/*
* must mark buffers dirty before XLogInsert, even though we'll still
* be changing their opaque fields below. set up right links.
*/
for (ptr = dist; ptr; ptr = ptr->next)
{
MarkBufferDirty(ptr->buffer);
GistPageGetOpaque(ptr->page)->rightlink = (ptr->next) ?
ptr->next->block.blkno : rrlink;
}
/* restore splitted non-root page */
if (state->stack->blkno != GIST_ROOT_BLKNO)
{
PageRestoreTempPage(dist->page, BufferGetPage(dist->buffer));
dist->page = BufferGetPage(dist->buffer);
}
if (!state->r->rd_istemp)
{
XLogRecPtr recptr;
XLogRecData *rdata;
rdata = formSplitRdata(state->r, state->stack->blkno,
is_leaf, &(state->key), dist);
recptr = XLogInsert(RM_GIST_ID, XLOG_GIST_PAGE_SPLIT, rdata);
for (ptr = dist; ptr; ptr = ptr->next)
{
PageSetLSN(ptr->page, recptr);
PageSetTLI(ptr->page, ThisTimeLineID);
}
}
else
{
for (ptr = dist; ptr; ptr = ptr->next)
{
PageSetLSN(ptr->page, XLogRecPtrForTemp);
}
}
/* set up NSN */
oldnsn = GistPageGetOpaque(dist->page)->nsn;
if (state->stack->blkno == GIST_ROOT_BLKNO)
/* if root split we should put initial value */
oldnsn = PageGetLSN(dist->page);
for (ptr = dist; ptr; ptr = ptr->next)
{
/* only for last set oldnsn */
GistPageGetOpaque(ptr->page)->nsn = (ptr->next) ?
PageGetLSN(ptr->page) : oldnsn;
}
/*
* release buffers, if it was a root split then release all buffers
* because we create all buffers
*/
ptr = (state->stack->blkno == GIST_ROOT_BLKNO) ? dist : dist->next;
for (; ptr; ptr = ptr->next)
UnlockReleaseBuffer(ptr->buffer);
if (state->stack->blkno == GIST_ROOT_BLKNO)
{
gistnewroot(state->r, state->stack->buffer, state->itup, state->ituplen, &(state->key));
state->needInsertComplete = false;
}
END_CRIT_SECTION();
}
else
{
/* enough space */
START_CRIT_SECTION();
if (!is_leaf)
PageIndexTupleDelete(state->stack->page, state->stack->childoffnum);
gistfillbuffer(state->r, state->stack->page, state->itup, state->ituplen, InvalidOffsetNumber);
MarkBufferDirty(state->stack->buffer);
if (!state->r->rd_istemp)
{
OffsetNumber noffs = 0,
offs[1];
XLogRecPtr recptr;
XLogRecData *rdata;
if (!is_leaf)
{
/* only on inner page we should delete previous version */
offs[0] = state->stack->childoffnum;
noffs = 1;
}
rdata = formUpdateRdata(state->r, state->stack->buffer,
offs, noffs,
state->itup, state->ituplen,
&(state->key));
recptr = XLogInsert(RM_GIST_ID, XLOG_GIST_PAGE_UPDATE, rdata);
PageSetLSN(state->stack->page, recptr);
PageSetTLI(state->stack->page, ThisTimeLineID);
}
else
PageSetLSN(state->stack->page, XLogRecPtrForTemp);
if (state->stack->blkno == GIST_ROOT_BLKNO)
state->needInsertComplete = false;
END_CRIT_SECTION();
if (state->ituplen > 1)
{ /* previous is_splitted==true */
/*
* child was splited, so we must form union for insertion in
* parent
*/
IndexTuple newtup = gistunion(state->r, state->itup, state->ituplen, giststate);
ItemPointerSetBlockNumber(&(newtup->t_tid), state->stack->blkno);
state->itup[0] = newtup;
state->ituplen = 1;
}
else if (is_leaf)
{
/*
* itup[0] store key to adjust parent, we set it to valid to
* correct check by GistTupleIsInvalid macro in gistgetadjusted()
*/
ItemPointerSetBlockNumber(&(state->itup[0]->t_tid), state->stack->blkno);
GistTupleSetValid(state->itup[0]);
}
}
return is_splitted;
}
/*
* Vacuum a regular (non-root) leaf page
*
* We must delete tuples that are targeted for deletion by the VACUUM,
* but not move any tuples that are referenced by outside links; we assume
* those are the ones that are heads of chains.
*
* If we find a REDIRECT that was made by a concurrently-running transaction,
* we must add its target TID to pendingList. (We don't try to visit the
* target immediately, first because we don't want VACUUM locking more than
* one buffer at a time, and second because the duplicate-filtering logic
* in spgAddPendingTID is useful to ensure we can't get caught in an infinite
* loop in the face of continuous concurrent insertions.)
*
* If forPending is true, we are examining the page as a consequence of
* chasing a redirect link, not as part of the normal sequential scan.
* We still vacuum the page normally, but we don't increment the stats
* about live tuples; else we'd double-count those tuples, since the page
* has been or will be visited in the sequential scan as well.
*/
static void
vacuumLeafPage(spgBulkDeleteState *bds, Relation index, Buffer buffer,
bool forPending)
{
Page page = BufferGetPage(buffer);
spgxlogVacuumLeaf xlrec;
OffsetNumber toDead[MaxIndexTuplesPerPage];
OffsetNumber toPlaceholder[MaxIndexTuplesPerPage];
OffsetNumber moveSrc[MaxIndexTuplesPerPage];
OffsetNumber moveDest[MaxIndexTuplesPerPage];
OffsetNumber chainSrc[MaxIndexTuplesPerPage];
OffsetNumber chainDest[MaxIndexTuplesPerPage];
OffsetNumber predecessor[MaxIndexTuplesPerPage + 1];
bool deletable[MaxIndexTuplesPerPage + 1];
int nDeletable;
OffsetNumber i,
max = PageGetMaxOffsetNumber(page);
memset(predecessor, 0, sizeof(predecessor));
memset(deletable, 0, sizeof(deletable));
nDeletable = 0;
/* Scan page, identify tuples to delete, accumulate stats */
for (i = FirstOffsetNumber; i <= max; i++)
{
SpGistLeafTuple lt;
lt = (SpGistLeafTuple) PageGetItem(page,
PageGetItemId(page, i));
if (lt->tupstate == SPGIST_LIVE)
{
Assert(ItemPointerIsValid(<->heapPtr));
if (bds->callback(<->heapPtr, bds->callback_state))
{
bds->stats->tuples_removed += 1;
deletable[i] = true;
nDeletable++;
}
else
{
if (!forPending)
bds->stats->num_index_tuples += 1;
}
/* Form predecessor map, too */
if (lt->nextOffset != InvalidOffsetNumber)
{
/* paranoia about corrupted chain links */
if (lt->nextOffset < FirstOffsetNumber ||
lt->nextOffset > max ||
predecessor[lt->nextOffset] != InvalidOffsetNumber)
elog(ERROR, "inconsistent tuple chain links in page %u of index \"%s\"",
BufferGetBlockNumber(buffer),
RelationGetRelationName(index));
predecessor[lt->nextOffset] = i;
}
}
else if (lt->tupstate == SPGIST_REDIRECT)
{
SpGistDeadTuple dt = (SpGistDeadTuple) lt;
Assert(dt->nextOffset == InvalidOffsetNumber);
Assert(ItemPointerIsValid(&dt->pointer));
/*
* Add target TID to pending list if the redirection could have
* happened since VACUUM started.
*
* Note: we could make a tighter test by seeing if the xid is
* "running" according to the active snapshot; but snapmgr.c doesn't
* currently export a suitable API, and it's not entirely clear
* that a tighter test is worth the cycles anyway.
*/
if (TransactionIdFollowsOrEquals(dt->xid, bds->myXmin))
spgAddPendingTID(bds, &dt->pointer);
}
else
{
Assert(lt->nextOffset == InvalidOffsetNumber);
}
}
if (nDeletable == 0)
return; /* nothing more to do */
/*----------
* Figure out exactly what we have to do. We do this separately from
* actually modifying the page, mainly so that we have a representation
* that can be dumped into WAL and then the replay code can do exactly
* the same thing. The output of this step consists of six arrays
* describing four kinds of operations, to be performed in this order:
*
* toDead[]: tuple numbers to be replaced with DEAD tuples
* toPlaceholder[]: tuple numbers to be replaced with PLACEHOLDER tuples
* moveSrc[]: tuple numbers that need to be relocated to another offset
* (replacing the tuple there) and then replaced with PLACEHOLDER tuples
* moveDest[]: new locations for moveSrc tuples
* chainSrc[]: tuple numbers whose chain links (nextOffset) need updates
* chainDest[]: new values of nextOffset for chainSrc members
*
* It's easiest to figure out what we have to do by processing tuple
* chains, so we iterate over all the tuples (not just the deletable
* ones!) to identify chain heads, then chase down each chain and make
* work item entries for deletable tuples within the chain.
*----------
*/
xlrec.nDead = xlrec.nPlaceholder = xlrec.nMove = xlrec.nChain = 0;
for (i = FirstOffsetNumber; i <= max; i++)
{
SpGistLeafTuple head;
bool interveningDeletable;
OffsetNumber prevLive;
OffsetNumber j;
head = (SpGistLeafTuple) PageGetItem(page,
PageGetItemId(page, i));
if (head->tupstate != SPGIST_LIVE)
continue; /* can't be a chain member */
if (predecessor[i] != 0)
continue; /* not a chain head */
/* initialize ... */
interveningDeletable = false;
prevLive = deletable[i] ? InvalidOffsetNumber : i;
/* scan down the chain ... */
j = head->nextOffset;
while (j != InvalidOffsetNumber)
{
SpGistLeafTuple lt;
lt = (SpGistLeafTuple) PageGetItem(page,
PageGetItemId(page, j));
if (lt->tupstate != SPGIST_LIVE)
{
/* all tuples in chain should be live */
elog(ERROR, "unexpected SPGiST tuple state: %d",
lt->tupstate);
}
if (deletable[j])
{
/* This tuple should be replaced by a placeholder */
toPlaceholder[xlrec.nPlaceholder] = j;
xlrec.nPlaceholder++;
/* previous live tuple's chain link will need an update */
interveningDeletable = true;
}
else if (prevLive == InvalidOffsetNumber)
{
/*
* This is the first live tuple in the chain. It has to move
* to the head position.
*/
moveSrc[xlrec.nMove] = j;
moveDest[xlrec.nMove] = i;
xlrec.nMove++;
/* Chain updates will be applied after the move */
prevLive = i;
interveningDeletable = false;
}
else
{
/*
* Second or later live tuple. Arrange to re-chain it to the
* previous live one, if there was a gap.
*/
if (interveningDeletable)
{
chainSrc[xlrec.nChain] = prevLive;
chainDest[xlrec.nChain] = j;
xlrec.nChain++;
}
prevLive = j;
interveningDeletable = false;
}
j = lt->nextOffset;
}
if (prevLive == InvalidOffsetNumber)
{
/* The chain is entirely removable, so we need a DEAD tuple */
toDead[xlrec.nDead] = i;
xlrec.nDead++;
}
else if (interveningDeletable)
{
/* One or more deletions at end of chain, so close it off */
chainSrc[xlrec.nChain] = prevLive;
chainDest[xlrec.nChain] = InvalidOffsetNumber;
xlrec.nChain++;
}
}
/* sanity check ... */
if (nDeletable != xlrec.nDead + xlrec.nPlaceholder + xlrec.nMove)
elog(ERROR, "inconsistent counts of deletable tuples");
/* Do the updates */
START_CRIT_SECTION();
spgPageIndexMultiDelete(&bds->spgstate, page,
toDead, xlrec.nDead,
SPGIST_DEAD, SPGIST_DEAD,
InvalidBlockNumber, InvalidOffsetNumber);
spgPageIndexMultiDelete(&bds->spgstate, page,
toPlaceholder, xlrec.nPlaceholder,
SPGIST_PLACEHOLDER, SPGIST_PLACEHOLDER,
InvalidBlockNumber, InvalidOffsetNumber);
/*
* We implement the move step by swapping the line pointers of the source
* and target tuples, then replacing the newly-source tuples with
* placeholders. This is perhaps unduly friendly with the page data
* representation, but it's fast and doesn't risk page overflow when a
* tuple to be relocated is large.
*/
for (i = 0; i < xlrec.nMove; i++)
{
ItemId idSrc = PageGetItemId(page, moveSrc[i]);
ItemId idDest = PageGetItemId(page, moveDest[i]);
ItemIdData tmp;
tmp = *idSrc;
*idSrc = *idDest;
*idDest = tmp;
}
spgPageIndexMultiDelete(&bds->spgstate, page,
moveSrc, xlrec.nMove,
SPGIST_PLACEHOLDER, SPGIST_PLACEHOLDER,
InvalidBlockNumber, InvalidOffsetNumber);
for (i = 0; i < xlrec.nChain; i++)
{
SpGistLeafTuple lt;
lt = (SpGistLeafTuple) PageGetItem(page,
PageGetItemId(page, chainSrc[i]));
Assert(lt->tupstate == SPGIST_LIVE);
lt->nextOffset = chainDest[i];
}
MarkBufferDirty(buffer);
if (RelationNeedsWAL(index))
{
XLogRecPtr recptr;
XLogBeginInsert();
STORE_STATE(&bds->spgstate, xlrec.stateSrc);
XLogRegisterData((char *) &xlrec, SizeOfSpgxlogVacuumLeaf);
/* sizeof(xlrec) should be a multiple of sizeof(OffsetNumber) */
XLogRegisterData((char *) toDead, sizeof(OffsetNumber) * xlrec.nDead);
XLogRegisterData((char *) toPlaceholder, sizeof(OffsetNumber) * xlrec.nPlaceholder);
XLogRegisterData((char *) moveSrc, sizeof(OffsetNumber) * xlrec.nMove);
XLogRegisterData((char *) moveDest, sizeof(OffsetNumber) * xlrec.nMove);
XLogRegisterData((char *) chainSrc, sizeof(OffsetNumber) * xlrec.nChain);
XLogRegisterData((char *) chainDest, sizeof(OffsetNumber) * xlrec.nChain);
XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
recptr = XLogInsert(RM_SPGIST_ID, XLOG_SPGIST_VACUUM_LEAF);
PageSetLSN(page, recptr);
}
END_CRIT_SECTION();
}
/*
* Routine to build an index. Basically calls insert over and over.
*
* XXX: it would be nice to implement some sort of bulk-loading
* algorithm, but it is not clear how to do that.
*/
Datum
gistbuild(PG_FUNCTION_ARGS)
{
MIRROREDLOCK_BUFMGR_DECLARE;
Relation heap = (Relation) PG_GETARG_POINTER(0);
Relation index = (Relation) PG_GETARG_POINTER(1);
IndexInfo *indexInfo = (IndexInfo *) PG_GETARG_POINTER(2);
IndexBuildResult *result;
double reltuples;
GISTBuildState buildstate;
Buffer buffer;
Page page;
/*
* We expect to be called exactly once for any index relation. If that's
* not the case, big trouble's what we have.
*/
if (RelationGetNumberOfBlocks(index) != 0)
elog(ERROR, "index \"%s\" already contains data",
RelationGetRelationName(index));
/* no locking is needed */
initGISTstate(&buildstate.giststate, index);
// -------- MirroredLock ----------
MIRROREDLOCK_BUFMGR_LOCK;
/* initialize the root page */
buffer = gistNewBuffer(index);
Assert(BufferGetBlockNumber(buffer) == GIST_ROOT_BLKNO);
page = BufferGetPage(buffer);
START_CRIT_SECTION();
GISTInitBuffer(buffer, F_LEAF);
MarkBufferDirty(buffer);
if (!index->rd_istemp)
{
XLogRecPtr recptr;
XLogRecData *rdata;
rdata = formCreateRData(index);
recptr = XLogInsert(RM_GIST_ID, XLOG_GIST_CREATE_INDEX, rdata);
PageSetLSN(page, recptr);
PageSetTLI(page, ThisTimeLineID);
}
else
PageSetLSN(page, XLogRecPtrForTemp);
UnlockReleaseBuffer(buffer);
MIRROREDLOCK_BUFMGR_UNLOCK;
// -------- MirroredLock ----------
END_CRIT_SECTION();
/* build the index */
buildstate.numindexattrs = indexInfo->ii_NumIndexAttrs;
buildstate.indtuples = 0;
/*
* create a temporary memory context that is reset once for each tuple
* inserted into the index
*/
buildstate.tmpCtx = createTempGistContext();
/* do the heap scan */
reltuples = IndexBuildScan(heap, index, indexInfo,
gistbuildCallback, (void *) &buildstate);
/* okay, all heap tuples are indexed */
MemoryContextDelete(buildstate.tmpCtx);
freeGISTstate(&buildstate.giststate);
/*
* Return statistics
*/
result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
result->heap_tuples = reltuples;
result->index_tuples = buildstate.indtuples;
PG_RETURN_POINTER(result);
}
/*
* Clean up redirect and placeholder tuples on the given page
*
* Redirect tuples can be marked placeholder once they're old enough.
* Placeholder tuples can be removed if it won't change the offsets of
* non-placeholder ones.
*
* Unlike the routines above, this works on both leaf and inner pages.
*/
static void
vacuumRedirectAndPlaceholder(Relation index, Buffer buffer)
{
Page page = BufferGetPage(buffer);
SpGistPageOpaque opaque = SpGistPageGetOpaque(page);
OffsetNumber i,
max = PageGetMaxOffsetNumber(page),
firstPlaceholder = InvalidOffsetNumber;
bool hasNonPlaceholder = false;
bool hasUpdate = false;
OffsetNumber itemToPlaceholder[MaxIndexTuplesPerPage];
OffsetNumber itemnos[MaxIndexTuplesPerPage];
spgxlogVacuumRedirect xlrec;
xlrec.nToPlaceholder = 0;
xlrec.newestRedirectXid = InvalidTransactionId;
START_CRIT_SECTION();
/*
* Scan backwards to convert old redirection tuples to placeholder tuples,
* and identify location of last non-placeholder tuple while at it.
*/
for (i = max;
i >= FirstOffsetNumber &&
(opaque->nRedirection > 0 || !hasNonPlaceholder);
i--)
{
SpGistDeadTuple dt;
dt = (SpGistDeadTuple) PageGetItem(page, PageGetItemId(page, i));
if (dt->tupstate == SPGIST_REDIRECT &&
TransactionIdPrecedes(dt->xid, RecentGlobalXmin))
{
dt->tupstate = SPGIST_PLACEHOLDER;
Assert(opaque->nRedirection > 0);
opaque->nRedirection--;
opaque->nPlaceholder++;
/* remember newest XID among the removed redirects */
if (!TransactionIdIsValid(xlrec.newestRedirectXid) ||
TransactionIdPrecedes(xlrec.newestRedirectXid, dt->xid))
xlrec.newestRedirectXid = dt->xid;
ItemPointerSetInvalid(&dt->pointer);
itemToPlaceholder[xlrec.nToPlaceholder] = i;
xlrec.nToPlaceholder++;
hasUpdate = true;
}
if (dt->tupstate == SPGIST_PLACEHOLDER)
{
if (!hasNonPlaceholder)
firstPlaceholder = i;
}
else
{
hasNonPlaceholder = true;
}
}
/*
* Any placeholder tuples at the end of page can safely be removed. We
* can't remove ones before the last non-placeholder, though, because we
* can't alter the offset numbers of non-placeholder tuples.
*/
if (firstPlaceholder != InvalidOffsetNumber)
{
/*
* We do not store this array to rdata because it's easy to recreate.
*/
for (i = firstPlaceholder; i <= max; i++)
itemnos[i - firstPlaceholder] = i;
i = max - firstPlaceholder + 1;
Assert(opaque->nPlaceholder >= i);
opaque->nPlaceholder -= i;
/* The array is surely sorted, so can use PageIndexMultiDelete */
PageIndexMultiDelete(page, itemnos, i);
hasUpdate = true;
}
xlrec.firstPlaceholder = firstPlaceholder;
if (hasUpdate)
MarkBufferDirty(buffer);
if (hasUpdate && RelationNeedsWAL(index))
{
XLogRecPtr recptr;
XLogBeginInsert();
XLogRegisterData((char *) &xlrec, SizeOfSpgxlogVacuumRedirect);
XLogRegisterData((char *) itemToPlaceholder,
sizeof(OffsetNumber) * xlrec.nToPlaceholder);
XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
recptr = XLogInsert(RM_SPGIST_ID, XLOG_SPGIST_VACUUM_REDIRECT);
PageSetLSN(page, recptr);
}
END_CRIT_SECTION();
}
/*
* brinbuild() -- build a new BRIN index.
*/
IndexBuildResult *
brinbuild(Relation heap, Relation index, IndexInfo *indexInfo)
{
ereport(LOG,(errmsg("brinbuild start")));
IndexBuildResult *result;
double reltuples;
double idxtuples;
BrinRevmap *revmap;
BrinBuildState *state;
Buffer meta;
BlockNumber pagesPerRange;
/*
* We expect to be called exactly once for any index relation.
*/
if (RelationGetNumberOfBlocks(index) != 0)
elog(ERROR, "index \"%s\" already contains data",
RelationGetRelationName(index));
/*
* Critical section not required, because on error the creation of the
* whole relation will be rolled back.
*/
meta = ReadBuffer(index, P_NEW);
Assert(BufferGetBlockNumber(meta) == BRIN_METAPAGE_BLKNO);
LockBuffer(meta, BUFFER_LOCK_EXCLUSIVE);
brin_metapage_init(BufferGetPage(meta), BrinGetPagesPerRange(index),
BRIN_CURRENT_VERSION);
MarkBufferDirty(meta);
if (RelationNeedsWAL(index))
{
xl_brin_createidx xlrec;
XLogRecPtr recptr;
Page page;
xlrec.version = BRIN_CURRENT_VERSION;
xlrec.pagesPerRange = BrinGetPagesPerRange(index);
XLogBeginInsert();
XLogRegisterData((char *) &xlrec, SizeOfBrinCreateIdx);
XLogRegisterBuffer(0, meta, REGBUF_WILL_INIT);
recptr = XLogInsert(RM_BRIN_ID, XLOG_BRIN_CREATE_INDEX);
page = BufferGetPage(meta);
PageSetLSN(page, recptr);
}
UnlockReleaseBuffer(meta);
/*
* Initialize our state, including the deformed tuple state.
*/
revmap = brinRevmapInitialize(index, &pagesPerRange, NULL);
state = initialize_brin_buildstate(index, revmap, pagesPerRange);
/*
* Now scan the relation. No syncscan allowed here because we want the
* heap blocks in physical order.
*/
reltuples = IndexBuildHeapScan(heap, index, indexInfo, false,
brinbuildCallback, (void *) state);
/* process the final batch */
form_and_insert_tuple(state);
/* release resources */
idxtuples = state->bs_numtuples;
brinRevmapTerminate(state->bs_rmAccess);
terminate_brin_buildstate(state);
/*
* Return statistics
*/
result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
result->heap_tuples = reltuples;
result->index_tuples = idxtuples;
ereport(LOG,(errmsg("brinbuild stop")));
return result;
}
/*
* Write the index tuples contained in *collector into the index's
* pending list.
*
* Function guarantees that all these tuples will be inserted consecutively,
* preserving order
*/
void
ginHeapTupleFastInsert(GinState *ginstate, GinTupleCollector *collector)
{
Relation index = ginstate->index;
Buffer metabuffer;
Page metapage;
GinMetaPageData *metadata = NULL;
XLogRecData rdata[2];
Buffer buffer = InvalidBuffer;
Page page = NULL;
ginxlogUpdateMeta data;
bool separateList = false;
bool needCleanup = false;
if (collector->ntuples == 0)
return;
data.node = index->rd_node;
data.ntuples = 0;
data.newRightlink = data.prevTail = InvalidBlockNumber;
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char *) &data;
rdata[0].len = sizeof(ginxlogUpdateMeta);
rdata[0].next = NULL;
metabuffer = ReadBuffer(index, GIN_METAPAGE_BLKNO);
metapage = BufferGetPage(metabuffer);
if (collector->sumsize + collector->ntuples * sizeof(ItemIdData) > GinListPageSize)
{
/*
* Total size is greater than one page => make sublist
*/
separateList = true;
}
else
{
LockBuffer(metabuffer, GIN_EXCLUSIVE);
metadata = GinPageGetMeta(metapage);
if (metadata->head == InvalidBlockNumber ||
collector->sumsize + collector->ntuples * sizeof(ItemIdData) > metadata->tailFreeSize)
{
/*
* Pending list is empty or total size is greater than freespace
* on tail page => make sublist
*
* We unlock metabuffer to keep high concurrency
*/
separateList = true;
LockBuffer(metabuffer, GIN_UNLOCK);
}
}
if (separateList)
{
/*
* We should make sublist separately and append it to the tail
*/
GinMetaPageData sublist;
memset(&sublist, 0, sizeof(GinMetaPageData));
makeSublist(index, collector->tuples, collector->ntuples, &sublist);
/*
* metapage was unlocked, see above
*/
LockBuffer(metabuffer, GIN_EXCLUSIVE);
metadata = GinPageGetMeta(metapage);
if (metadata->head == InvalidBlockNumber)
{
/*
* Main list is empty, so just insert sublist as main list
*/
START_CRIT_SECTION();
metadata->head = sublist.head;
metadata->tail = sublist.tail;
metadata->tailFreeSize = sublist.tailFreeSize;
metadata->nPendingPages = sublist.nPendingPages;
metadata->nPendingHeapTuples = sublist.nPendingHeapTuples;
}
else
{
/*
* Merge lists
*/
data.prevTail = metadata->tail;
data.newRightlink = sublist.head;
buffer = ReadBuffer(index, metadata->tail);
LockBuffer(buffer, GIN_EXCLUSIVE);
page = BufferGetPage(buffer);
rdata[0].next = rdata + 1;
rdata[1].buffer = buffer;
rdata[1].buffer_std = true;
rdata[1].data = NULL;
rdata[1].len = 0;
rdata[1].next = NULL;
Assert(GinPageGetOpaque(page)->rightlink == InvalidBlockNumber);
START_CRIT_SECTION();
GinPageGetOpaque(page)->rightlink = sublist.head;
MarkBufferDirty(buffer);
metadata->tail = sublist.tail;
metadata->tailFreeSize = sublist.tailFreeSize;
metadata->nPendingPages += sublist.nPendingPages;
metadata->nPendingHeapTuples += sublist.nPendingHeapTuples;
}
}
else
{
/*
* Insert into tail page. Metapage is already locked
*/
OffsetNumber l,
off;
int i,
tupsize;
char *ptr;
buffer = ReadBuffer(index, metadata->tail);
LockBuffer(buffer, GIN_EXCLUSIVE);
page = BufferGetPage(buffer);
off = (PageIsEmpty(page)) ? FirstOffsetNumber :
OffsetNumberNext(PageGetMaxOffsetNumber(page));
rdata[0].next = rdata + 1;
rdata[1].buffer = buffer;
rdata[1].buffer_std = true;
ptr = rdata[1].data = (char *) palloc(collector->sumsize);
rdata[1].len = collector->sumsize;
rdata[1].next = NULL;
data.ntuples = collector->ntuples;
START_CRIT_SECTION();
/*
* Increase counter of heap tuples
*/
Assert(GinPageGetOpaque(page)->maxoff <= metadata->nPendingHeapTuples);
GinPageGetOpaque(page)->maxoff++;
metadata->nPendingHeapTuples++;
for (i = 0; i < collector->ntuples; i++)
{
tupsize = IndexTupleSize(collector->tuples[i]);
l = PageAddItem(page, (Item) collector->tuples[i], tupsize, off, false, false);
if (l == InvalidOffsetNumber)
elog(ERROR, "failed to add item to index page in \"%s\"",
RelationGetRelationName(index));
memcpy(ptr, collector->tuples[i], tupsize);
ptr += tupsize;
off++;
}
Assert((ptr - rdata[1].data) <= collector->sumsize);
metadata->tailFreeSize = PageGetExactFreeSpace(page);
MarkBufferDirty(buffer);
}
/*
* Write metabuffer, make xlog entry
*/
MarkBufferDirty(metabuffer);
if (RelationNeedsWAL(index))
{
XLogRecPtr recptr;
memcpy(&data.metadata, metadata, sizeof(GinMetaPageData));
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_UPDATE_META_PAGE, rdata);
PageSetLSN(metapage, recptr);
if (buffer != InvalidBuffer)
{
PageSetLSN(page, recptr);
}
}
if (buffer != InvalidBuffer)
UnlockReleaseBuffer(buffer);
/*
* Force pending list cleanup when it becomes too long. And,
* ginInsertCleanup could take significant amount of time, so we prefer to
* call it when it can do all the work in a single collection cycle. In
* non-vacuum mode, it shouldn't require maintenance_work_mem, so fire it
* while pending list is still small enough to fit into work_mem.
*
* ginInsertCleanup() should not be called inside our CRIT_SECTION.
*/
if (metadata->nPendingPages * GIN_PAGE_FREESIZE > work_mem * 1024L)
needCleanup = true;
UnlockReleaseBuffer(metabuffer);
END_CRIT_SECTION();
if (needCleanup)
ginInsertCleanup(ginstate, false, NULL);
}
/*
* Write out a new shared or local map file with the given contents.
*
* The magic number and CRC are automatically updated in *newmap. On
* success, we copy the data to the appropriate permanent static variable.
*
* If write_wal is TRUE then an appropriate WAL message is emitted.
* (It will be false for bootstrap and WAL replay cases.)
*
* If send_sinval is TRUE then a SI invalidation message is sent.
* (This should be true except in bootstrap case.)
*
* If preserve_files is TRUE then the storage manager is warned not to
* delete the files listed in the map.
*
* Because this may be called during WAL replay when MyDatabaseId,
* DatabasePath, etc aren't valid, we require the caller to pass in suitable
* values. The caller is also responsible for being sure no concurrent
* map update could be happening.
*/
static void
write_relmap_file(bool shared, RelMapFile *newmap,
bool write_wal, bool send_sinval, bool preserve_files,
Oid dbid, Oid tsid, const char *dbpath)
{
int fd;
RelMapFile *realmap;
char mapfilename[MAXPGPATH];
/*
* Fill in the overhead fields and update CRC.
*/
newmap->magic = RELMAPPER_FILEMAGIC;
if (newmap->num_mappings < 0 || newmap->num_mappings > MAX_MAPPINGS)
elog(ERROR, "attempt to write bogus relation mapping");
INIT_CRC32C(newmap->crc);
COMP_CRC32C(newmap->crc, (char *) newmap, offsetof(RelMapFile, crc));
FIN_CRC32C(newmap->crc);
/*
* Open the target file. We prefer to do this before entering the
* critical section, so that an open() failure need not force PANIC.
*/
if (shared)
{
snprintf(mapfilename, sizeof(mapfilename), "global/%s",
RELMAPPER_FILENAME);
realmap = &shared_map;
}
else
{
snprintf(mapfilename, sizeof(mapfilename), "%s/%s",
dbpath, RELMAPPER_FILENAME);
realmap = &local_map;
}
fd = OpenTransientFile(mapfilename,
O_WRONLY | O_CREAT | PG_BINARY,
S_IRUSR | S_IWUSR);
if (fd < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open relation mapping file \"%s\": %m",
mapfilename)));
if (write_wal)
{
xl_relmap_update xlrec;
XLogRecPtr lsn;
/* now errors are fatal ... */
START_CRIT_SECTION();
xlrec.dbid = dbid;
xlrec.tsid = tsid;
xlrec.nbytes = sizeof(RelMapFile);
XLogBeginInsert();
XLogRegisterData((char *) (&xlrec), MinSizeOfRelmapUpdate);
XLogRegisterData((char *) newmap, sizeof(RelMapFile));
lsn = XLogInsert(RM_RELMAP_ID, XLOG_RELMAP_UPDATE);
/* As always, WAL must hit the disk before the data update does */
XLogFlush(lsn);
}
errno = 0;
if (write(fd, newmap, sizeof(RelMapFile)) != sizeof(RelMapFile))
{
/* if write didn't set errno, assume problem is no disk space */
if (errno == 0)
errno = ENOSPC;
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write to relation mapping file \"%s\": %m",
mapfilename)));
}
/*
* We choose to fsync the data to disk before considering the task done.
* It would be possible to relax this if it turns out to be a performance
* issue, but it would complicate checkpointing --- see notes for
* CheckPointRelationMap.
*/
if (pg_fsync(fd) != 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not fsync relation mapping file \"%s\": %m",
mapfilename)));
if (CloseTransientFile(fd))
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not close relation mapping file \"%s\": %m",
mapfilename)));
/*
* Now that the file is safely on disk, send sinval message to let other
* backends know to re-read it. We must do this inside the critical
* section: if for some reason we fail to send the message, we have to
* force a database-wide PANIC. Otherwise other backends might continue
* execution with stale mapping information, which would be catastrophic
* as soon as others began to use the now-committed data.
*/
if (send_sinval)
CacheInvalidateRelmap(dbid);
/*
* Make sure that the files listed in the map are not deleted if the outer
* transaction aborts. This had better be within the critical section
* too: it's not likely to fail, but if it did, we'd arrive at transaction
* abort with the files still vulnerable. PANICing will leave things in a
* good state on-disk.
*
* Note: we're cheating a little bit here by assuming that mapped files
* are either in pg_global or the database's default tablespace.
*/
if (preserve_files)
{
int32 i;
for (i = 0; i < newmap->num_mappings; i++)
{
RelFileNode rnode;
rnode.spcNode = tsid;
rnode.dbNode = dbid;
rnode.relNode = newmap->mappings[i].mapfilenode;
RelationPreserveStorage(rnode, false);
}
}
/* Success, update permanent copy */
memcpy(realmap, newmap, sizeof(RelMapFile));
/* Critical section done */
if (write_wal)
END_CRIT_SECTION();
}
/*
* Deletes pending list pages up to (not including) newHead page.
* If newHead == InvalidBlockNumber then function drops the whole list.
*
* metapage is pinned and exclusive-locked throughout this function.
*
* Returns true if another cleanup process is running concurrently
* (if so, we can just abandon our own efforts)
*/
static bool
shiftList(Relation index, Buffer metabuffer, BlockNumber newHead,
IndexBulkDeleteResult *stats)
{
Page metapage;
GinMetaPageData *metadata;
BlockNumber blknoToDelete;
metapage = BufferGetPage(metabuffer);
metadata = GinPageGetMeta(metapage);
blknoToDelete = metadata->head;
do
{
Page page;
int i;
int64 nDeletedHeapTuples = 0;
ginxlogDeleteListPages data;
XLogRecData rdata[1];
Buffer buffers[GIN_NDELETE_AT_ONCE];
data.node = index->rd_node;
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char *) &data;
rdata[0].len = sizeof(ginxlogDeleteListPages);
rdata[0].next = NULL;
data.ndeleted = 0;
while (data.ndeleted < GIN_NDELETE_AT_ONCE && blknoToDelete != newHead)
{
data.toDelete[data.ndeleted] = blknoToDelete;
buffers[data.ndeleted] = ReadBuffer(index, blknoToDelete);
LockBuffer(buffers[data.ndeleted], GIN_EXCLUSIVE);
page = BufferGetPage(buffers[data.ndeleted]);
data.ndeleted++;
if (GinPageIsDeleted(page))
{
/* concurrent cleanup process is detected */
for (i = 0; i < data.ndeleted; i++)
UnlockReleaseBuffer(buffers[i]);
return true;
}
nDeletedHeapTuples += GinPageGetOpaque(page)->maxoff;
blknoToDelete = GinPageGetOpaque(page)->rightlink;
}
if (stats)
stats->pages_deleted += data.ndeleted;
START_CRIT_SECTION();
metadata->head = blknoToDelete;
Assert(metadata->nPendingPages >= data.ndeleted);
metadata->nPendingPages -= data.ndeleted;
Assert(metadata->nPendingHeapTuples >= nDeletedHeapTuples);
metadata->nPendingHeapTuples -= nDeletedHeapTuples;
if (blknoToDelete == InvalidBlockNumber)
{
metadata->tail = InvalidBlockNumber;
metadata->tailFreeSize = 0;
metadata->nPendingPages = 0;
metadata->nPendingHeapTuples = 0;
}
MarkBufferDirty(metabuffer);
for (i = 0; i < data.ndeleted; i++)
{
page = BufferGetPage(buffers[i]);
GinPageGetOpaque(page)->flags = GIN_DELETED;
MarkBufferDirty(buffers[i]);
}
if (RelationNeedsWAL(index))
{
XLogRecPtr recptr;
memcpy(&data.metadata, metadata, sizeof(GinMetaPageData));
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_DELETE_LISTPAGE, rdata);
PageSetLSN(metapage, recptr);
for (i = 0; i < data.ndeleted; i++)
{
page = BufferGetPage(buffers[i]);
PageSetLSN(page, recptr);
}
}
for (i = 0; i < data.ndeleted; i++)
UnlockReleaseBuffer(buffers[i]);
END_CRIT_SECTION();
} while (blknoToDelete != newHead);
return false;
}
/*
* Drop a table space
*
* Be careful to check that the tablespace is empty.
*/
void
DropTableSpace(DropTableSpaceStmt *stmt)
{
#ifdef HAVE_SYMLINK
char *tablespacename = stmt->tablespacename;
HeapScanDesc scandesc;
Relation rel;
HeapTuple tuple;
ScanKeyData entry[1];
Oid tablespaceoid;
/*
* Find the target tuple
*/
rel = heap_open(TableSpaceRelationId, RowExclusiveLock);
ScanKeyInit(&entry[0],
Anum_pg_tablespace_spcname,
BTEqualStrategyNumber, F_NAMEEQ,
CStringGetDatum(tablespacename));
scandesc = heap_beginscan(rel, SnapshotNow, 1, entry);
tuple = heap_getnext(scandesc, ForwardScanDirection);
if (!HeapTupleIsValid(tuple))
{
if (!stmt->missing_ok)
{
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("tablespace \"%s\" does not exist",
tablespacename)));
}
else
{
ereport(NOTICE,
(errmsg("tablespace \"%s\" does not exist, skipping",
tablespacename)));
/* XXX I assume I need one or both of these next two calls */
heap_endscan(scandesc);
heap_close(rel, NoLock);
}
return;
}
tablespaceoid = HeapTupleGetOid(tuple);
/* Must be tablespace owner */
if (!pg_tablespace_ownercheck(tablespaceoid, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_TABLESPACE,
tablespacename);
/* Disallow drop of the standard tablespaces, even by superuser */
if (tablespaceoid == GLOBALTABLESPACE_OID ||
tablespaceoid == DEFAULTTABLESPACE_OID)
aclcheck_error(ACLCHECK_NO_PRIV, ACL_KIND_TABLESPACE,
tablespacename);
/*
* Remove the pg_tablespace tuple (this will roll back if we fail below)
*/
simple_heap_delete(rel, &tuple->t_self);
heap_endscan(scandesc);
/*
* Remove any comments on this tablespace.
*/
DeleteSharedComments(tablespaceoid, TableSpaceRelationId);
/*
* Remove dependency on owner.
*/
deleteSharedDependencyRecordsFor(TableSpaceRelationId, tablespaceoid, 0);
/*
* Acquire TablespaceCreateLock to ensure that no TablespaceCreateDbspace
* is running concurrently.
*/
LWLockAcquire(TablespaceCreateLock, LW_EXCLUSIVE);
/*
* Try to remove the physical infrastructure.
*/
if (!destroy_tablespace_directories(tablespaceoid, false))
{
/*
* Not all files deleted? However, there can be lingering empty files
* in the directories, left behind by for example DROP TABLE, that
* have been scheduled for deletion at next checkpoint (see comments
* in mdunlink() for details). We could just delete them immediately,
* but we can't tell them apart from important data files that we
* mustn't delete. So instead, we force a checkpoint which will clean
* out any lingering files, and try again.
*/
RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
if (!destroy_tablespace_directories(tablespaceoid, false))
{
/* Still not empty, the files must be important then */
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("tablespace \"%s\" is not empty",
tablespacename)));
}
}
/* Record the filesystem change in XLOG */
{
xl_tblspc_drop_rec xlrec;
XLogRecData rdata[1];
xlrec.ts_id = tablespaceoid;
rdata[0].data = (char *) &xlrec;
rdata[0].len = sizeof(xl_tblspc_drop_rec);
rdata[0].buffer = InvalidBuffer;
rdata[0].next = NULL;
(void) XLogInsert(RM_TBLSPC_ID, XLOG_TBLSPC_DROP, rdata);
}
/*
* Note: because we checked that the tablespace was empty, there should be
* no need to worry about flushing shared buffers or free space map
* entries for relations in the tablespace.
*/
/*
* Force synchronous commit, to minimize the window between removing the
* files on-disk and marking the transaction committed. It's not great
* that there is any window at all, but definitely we don't want to make
* it larger than necessary.
*/
ForceSyncCommit();
/*
* Allow TablespaceCreateDbspace again.
*/
LWLockRelease(TablespaceCreateLock);
/* We keep the lock on pg_tablespace until commit */
heap_close(rel, NoLock);
#else /* !HAVE_SYMLINK */
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("tablespaces are not supported on this platform")));
#endif /* HAVE_SYMLINK */
}
/*
* Create a table space
*
* Only superusers can create a tablespace. This seems a reasonable restriction
* since we're determining the system layout and, anyway, we probably have
* root if we're doing this kind of activity
*/
Oid
CreateTableSpace(CreateTableSpaceStmt *stmt)
{
#ifdef HAVE_SYMLINK
Relation rel;
Datum values[Natts_pg_tablespace];
bool nulls[Natts_pg_tablespace];
HeapTuple tuple;
Oid tablespaceoid;
char *location;
Oid ownerId;
Datum newOptions;
/* Must be super user */
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied to create tablespace \"%s\"",
stmt->tablespacename),
errhint("Must be superuser to create a tablespace.")));
/* However, the eventual owner of the tablespace need not be */
if (stmt->owner)
ownerId = get_rolespec_oid(stmt->owner, false);
else
ownerId = GetUserId();
/* Unix-ify the offered path, and strip any trailing slashes */
location = pstrdup(stmt->location);
canonicalize_path(location);
/* disallow quotes, else CREATE DATABASE would be at risk */
if (strchr(location, '\''))
ereport(ERROR,
(errcode(ERRCODE_INVALID_NAME),
errmsg("tablespace location cannot contain single quotes")));
/*
* Allowing relative paths seems risky
*
* this also helps us ensure that location is not empty or whitespace
*/
if (!is_absolute_path(location))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location must be an absolute path")));
/*
* Check that location isn't too long. Remember that we're going to append
* 'PG_XXX/<dboid>/<relid>_<fork>.<nnn>'. FYI, we never actually
* reference the whole path here, but mkdir() uses the first two parts.
*/
if (strlen(location) + 1 + strlen(TABLESPACE_VERSION_DIRECTORY) + 1 +
OIDCHARS + 1 + OIDCHARS + 1 + FORKNAMECHARS + 1 + OIDCHARS > MAXPGPATH)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location \"%s\" is too long",
location)));
/* Warn if the tablespace is in the data directory. */
if (path_is_prefix_of_path(DataDir, location))
ereport(WARNING,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location should not be inside the data directory")));
/*
* Disallow creation of tablespaces named "pg_xxx"; we reserve this
* namespace for system purposes.
*/
if (!allowSystemTableMods && IsReservedName(stmt->tablespacename))
ereport(ERROR,
(errcode(ERRCODE_RESERVED_NAME),
errmsg("unacceptable tablespace name \"%s\"",
stmt->tablespacename),
errdetail("The prefix \"pg_\" is reserved for system tablespaces.")));
/*
* Check that there is no other tablespace by this name. (The unique
* index would catch this anyway, but might as well give a friendlier
* message.)
*/
if (OidIsValid(get_tablespace_oid(stmt->tablespacename, true)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("tablespace \"%s\" already exists",
stmt->tablespacename)));
/*
* Insert tuple into pg_tablespace. The purpose of doing this first is to
* lock the proposed tablename against other would-be creators. The
* insertion will roll back if we find problems below.
*/
rel = heap_open(TableSpaceRelationId, RowExclusiveLock);
MemSet(nulls, false, sizeof(nulls));
values[Anum_pg_tablespace_spcname - 1] =
DirectFunctionCall1(namein, CStringGetDatum(stmt->tablespacename));
values[Anum_pg_tablespace_spcowner - 1] =
ObjectIdGetDatum(ownerId);
nulls[Anum_pg_tablespace_spcacl - 1] = true;
/* Generate new proposed spcoptions (text array) */
newOptions = transformRelOptions((Datum) 0,
stmt->options,
NULL, NULL, false, false);
(void) tablespace_reloptions(newOptions, true);
if (newOptions != (Datum) 0)
values[Anum_pg_tablespace_spcoptions - 1] = newOptions;
else
nulls[Anum_pg_tablespace_spcoptions - 1] = true;
tuple = heap_form_tuple(rel->rd_att, values, nulls);
tablespaceoid = simple_heap_insert(rel, tuple);
CatalogUpdateIndexes(rel, tuple);
heap_freetuple(tuple);
/* Record dependency on owner */
recordDependencyOnOwner(TableSpaceRelationId, tablespaceoid, ownerId);
/* Post creation hook for new tablespace */
InvokeObjectPostCreateHook(TableSpaceRelationId, tablespaceoid, 0);
create_tablespace_directories(location, tablespaceoid);
/* Record the filesystem change in XLOG */
{
xl_tblspc_create_rec xlrec;
xlrec.ts_id = tablespaceoid;
XLogBeginInsert();
XLogRegisterData((char *) &xlrec,
offsetof(xl_tblspc_create_rec, ts_path));
XLogRegisterData((char *) location, strlen(location) + 1);
(void) XLogInsert(RM_TBLSPC_ID, XLOG_TBLSPC_CREATE);
}
/*
* Force synchronous commit, to minimize the window between creating the
* symlink on-disk and marking the transaction committed. It's not great
* that there is any window at all, but definitely we don't want to make
* it larger than necessary.
*/
ForceSyncCommit();
pfree(location);
/* We keep the lock on pg_tablespace until commit */
heap_close(rel, NoLock);
return tablespaceoid;
#else /* !HAVE_SYMLINK */
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("tablespaces are not supported on this platform")));
return InvalidOid; /* keep compiler quiet */
#endif /* HAVE_SYMLINK */
}
/*
* Apply changes represented by GenericXLogState to the actual buffers,
* and emit a generic xlog record.
*/
XLogRecPtr
GenericXLogFinish(GenericXLogState *state)
{
XLogRecPtr lsn;
int i;
if (state->isLogged)
{
/* Logged relation: make xlog record in critical section. */
XLogBeginInsert();
START_CRIT_SECTION();
for (i = 0; i < MAX_GENERIC_XLOG_PAGES; i++)
{
PageData *pageData = &state->pages[i];
Page page;
PageHeader pageHeader;
if (BufferIsInvalid(pageData->buffer))
continue;
page = BufferGetPage(pageData->buffer);
pageHeader = (PageHeader) pageData->image;
if (pageData->flags & GENERIC_XLOG_FULL_IMAGE)
{
/*
* A full-page image does not require us to supply any xlog
* data. Just apply the image, being careful to zero the
* "hole" between pd_lower and pd_upper in order to avoid
* divergence between actual page state and what replay would
* produce.
*/
memcpy(page, pageData->image, pageHeader->pd_lower);
memset(page + pageHeader->pd_lower, 0,
pageHeader->pd_upper - pageHeader->pd_lower);
memcpy(page + pageHeader->pd_upper,
pageData->image + pageHeader->pd_upper,
BLCKSZ - pageHeader->pd_upper);
XLogRegisterBuffer(i, pageData->buffer,
REGBUF_FORCE_IMAGE | REGBUF_STANDARD);
}
else
{
/*
* In normal mode, calculate delta and write it as xlog data
* associated with this page.
*/
computeDelta(pageData, page, (Page) pageData->image);
/* Apply the image, with zeroed "hole" as above */
memcpy(page, pageData->image, pageHeader->pd_lower);
memset(page + pageHeader->pd_lower, 0,
pageHeader->pd_upper - pageHeader->pd_lower);
memcpy(page + pageHeader->pd_upper,
pageData->image + pageHeader->pd_upper,
BLCKSZ - pageHeader->pd_upper);
XLogRegisterBuffer(i, pageData->buffer, REGBUF_STANDARD);
XLogRegisterBufData(i, pageData->delta, pageData->deltaLen);
}
}
/* Insert xlog record */
lsn = XLogInsert(RM_GENERIC_ID, 0);
/* Set LSN and mark buffers dirty */
for (i = 0; i < MAX_GENERIC_XLOG_PAGES; i++)
{
PageData *pageData = &state->pages[i];
if (BufferIsInvalid(pageData->buffer))
continue;
PageSetLSN(BufferGetPage(pageData->buffer), lsn);
MarkBufferDirty(pageData->buffer);
}
END_CRIT_SECTION();
}
else
{
/* Unlogged relation: skip xlog-related stuff */
START_CRIT_SECTION();
for (i = 0; i < MAX_GENERIC_XLOG_PAGES; i++)
{
PageData *pageData = &state->pages[i];
if (BufferIsInvalid(pageData->buffer))
continue;
memcpy(BufferGetPage(pageData->buffer),
pageData->image,
BLCKSZ);
/* We don't worry about zeroing the "hole" in this case */
MarkBufferDirty(pageData->buffer);
}
END_CRIT_SECTION();
/* We don't have a LSN to return, in this case */
lsn = InvalidXLogRecPtr;
}
for (i = 0; i < MAX_GENERIC_XLOG_PAGES; i++)
pfree(state->pages[i].image);
pfree(state);
return lsn;
}