diff options
Diffstat (limited to 'src/backend/storage/smgr/smgr.c')
| -rw-r--r-- | src/backend/storage/smgr/smgr.c | 157 |
1 files changed, 156 insertions, 1 deletions
diff --git a/src/backend/storage/smgr/smgr.c b/src/backend/storage/smgr/smgr.c index 09ee4144c50..d242744a4d7 100644 --- a/src/backend/storage/smgr/smgr.c +++ b/src/backend/storage/smgr/smgr.c @@ -11,7 +11,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/storage/smgr/smgr.c,v 1.69 2004/02/10 01:55:26 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/storage/smgr/smgr.c,v 1.70 2004/02/11 22:55:25 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -94,6 +94,29 @@ typedef struct PendingRelDelete static PendingRelDelete *pendingDeletes = NULL; /* head of linked list */ +/* + * Declarations for smgr-related XLOG records + * + * Note: we log file creation and truncation here, but logging of deletion + * actions is handled by xact.c, because it is part of transaction commit. + */ + +/* XLOG gives us high 4 bits */ +#define XLOG_SMGR_CREATE 0x10 +#define XLOG_SMGR_TRUNCATE 0x20 + +typedef struct xl_smgr_create +{ + RelFileNode rnode; +} xl_smgr_create; + +typedef struct xl_smgr_truncate +{ + BlockNumber blkno; + RelFileNode rnode; +} xl_smgr_truncate; + + /* local function prototypes */ static void smgrshutdown(int code, Datum arg); static void smgr_internal_unlink(RelFileNode rnode, int which, @@ -274,6 +297,9 @@ smgrclosenode(RelFileNode rnode) void smgrcreate(SMgrRelation reln, bool isTemp, bool isRedo) { + XLogRecPtr lsn; + XLogRecData rdata; + xl_smgr_create xlrec; PendingRelDelete *pending; if (! (*(smgrsw[reln->smgr_which].smgr_create)) (reln, isRedo)) @@ -286,6 +312,20 @@ smgrcreate(SMgrRelation reln, bool isTemp, bool isRedo) if (isRedo) return; + /* + * Make a non-transactional XLOG entry showing the file creation. It's + * non-transactional because we should replay it whether the transaction + * commits or not; if not, the file will be dropped at abort time. + */ + xlrec.rnode = reln->smgr_rnode; + + rdata.buffer = InvalidBuffer; + rdata.data = (char *) &xlrec; + rdata.len = sizeof(xlrec); + rdata.next = NULL; + + lsn = XLogInsert(RM_SMGR_ID, XLOG_SMGR_CREATE | XLOG_NO_TRAN, &rdata); + /* Add the relation to the list of stuff to delete at abort */ pending = (PendingRelDelete *) MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete)); @@ -488,6 +528,9 @@ BlockNumber smgrtruncate(SMgrRelation reln, BlockNumber nblocks) { BlockNumber newblks; + XLogRecPtr lsn; + XLogRecData rdata; + xl_smgr_truncate xlrec; /* * Tell the free space map to forget anything it may have stored @@ -496,6 +539,7 @@ smgrtruncate(SMgrRelation reln, BlockNumber nblocks) */ FreeSpaceMapTruncateRel(&reln->smgr_rnode, nblocks); + /* Do the truncation */ newblks = (*(smgrsw[reln->smgr_which].smgr_truncate)) (reln, nblocks); if (newblks == InvalidBlockNumber) ereport(ERROR, @@ -505,6 +549,21 @@ smgrtruncate(SMgrRelation reln, BlockNumber nblocks) reln->smgr_rnode.relNode, nblocks))); + /* + * Make a non-transactional XLOG entry showing the file truncation. It's + * non-transactional because we should replay it whether the transaction + * commits or not; the underlying file change is certainly not reversible. + */ + xlrec.blkno = newblks; + xlrec.rnode = reln->smgr_rnode; + + rdata.buffer = InvalidBuffer; + rdata.data = (char *) &xlrec; + rdata.len = sizeof(xlrec); + rdata.next = NULL; + + lsn = XLogInsert(RM_SMGR_ID, XLOG_SMGR_TRUNCATE | XLOG_NO_TRAN, &rdata); + return newblks; } @@ -529,6 +588,41 @@ smgrDoPendingDeletes(bool isCommit) } /* + * smgrGetPendingDeletes() -- Get a list of relations to be deleted. + * + * The return value is the number of relations scheduled for termination. + * *ptr is set to point to a freshly-palloc'd array of RelFileNodes. + * If there are no relations to be deleted, *ptr is set to NULL. + */ +int +smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr) +{ + int nrels; + RelFileNode *rptr; + PendingRelDelete *pending; + + nrels = 0; + for (pending = pendingDeletes; pending != NULL; pending = pending->next) + { + if (pending->atCommit == forCommit) + nrels++; + } + if (nrels == 0) + { + *ptr = NULL; + return 0; + } + rptr = (RelFileNode *) palloc(nrels * sizeof(RelFileNode)); + *ptr = rptr; + for (pending = pendingDeletes; pending != NULL; pending = pending->next) + { + if (pending->atCommit == forCommit) + *rptr++ = pending->relnode; + } + return nrels; +} + +/* * smgrcommit() -- Prepare to commit changes made during the current * transaction. * @@ -595,14 +689,75 @@ smgrsync(void) void smgr_redo(XLogRecPtr lsn, XLogRecord *record) { + uint8 info = record->xl_info & ~XLR_INFO_MASK; + + if (info == XLOG_SMGR_CREATE) + { + xl_smgr_create *xlrec = (xl_smgr_create *) XLogRecGetData(record); + SMgrRelation reln; + + reln = smgropen(xlrec->rnode); + smgrcreate(reln, false, true); + } + else if (info == XLOG_SMGR_TRUNCATE) + { + xl_smgr_truncate *xlrec = (xl_smgr_truncate *) XLogRecGetData(record); + SMgrRelation reln; + BlockNumber newblks; + + reln = smgropen(xlrec->rnode); + + /* Can't use smgrtruncate because it would try to xlog */ + + /* + * Tell the free space map to forget anything it may have stored + * for the about-to-be-deleted blocks. We want to be sure it + * won't return bogus block numbers later on. + */ + FreeSpaceMapTruncateRel(&reln->smgr_rnode, xlrec->blkno); + + /* Do the truncation */ + newblks = (*(smgrsw[reln->smgr_which].smgr_truncate)) (reln, + xlrec->blkno); + if (newblks == InvalidBlockNumber) + ereport(WARNING, + (errcode_for_file_access(), + errmsg("could not truncate relation %u/%u to %u blocks: %m", + reln->smgr_rnode.tblNode, + reln->smgr_rnode.relNode, + xlrec->blkno))); + } + else + elog(PANIC, "smgr_redo: unknown op code %u", info); } void smgr_undo(XLogRecPtr lsn, XLogRecord *record) { + /* Since we have no transactional WAL entries, should never undo */ + elog(PANIC, "smgr_undo: cannot undo"); } void smgr_desc(char *buf, uint8 xl_info, char *rec) { + uint8 info = xl_info & ~XLR_INFO_MASK; + + if (info == XLOG_SMGR_CREATE) + { + xl_smgr_create *xlrec = (xl_smgr_create *) rec; + + sprintf(buf + strlen(buf), "file create: %u/%u", + xlrec->rnode.tblNode, xlrec->rnode.relNode); + } + else if (info == XLOG_SMGR_TRUNCATE) + { + xl_smgr_truncate *xlrec = (xl_smgr_truncate *) rec; + + sprintf(buf + strlen(buf), "file truncate: %u/%u to %u blocks", + xlrec->rnode.tblNode, xlrec->rnode.relNode, + xlrec->blkno); + } + else + strcat(buf, "UNKNOWN"); } |