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Restructure smgr API as per recent proposal. smgr no longer depends on

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the relcache, and so the notion of 'blind write' is gone.  This should
improve efficiency in bgwriter and background checkpoint processes.
Internal restructuring in md.c to remove the not-very-useful array of
MdfdVec objects --- might as well just use pointers.
Also remove the long-dead 'persistent main memory' storage manager (mm.c),
since it seems quite unlikely to ever get resurrected.
This commit is contained in:
Tom Lane
2004-02-10 01:55:27 +00:00
parent f06e79525a
commit 87bd956385
37 changed files with 933 additions and 1776 deletions
Download Patch File Download Diff File Expand all files Collapse all files

249
src/backend/storage/buffer/bufmgr.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.156 2004/02/06 19:36:18 wieck Exp $
* $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.157 2004/02/10 01:55:25 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -85,7 +85,7 @@ static Buffer ReadBufferInternal(Relation reln, BlockNumber blockNum,
bool bufferLockHeld);
static BufferDesc *BufferAlloc(Relation reln, BlockNumber blockNum,
bool *foundPtr);
static bool BufferReplace(BufferDesc *bufHdr);
static void BufferReplace(BufferDesc *bufHdr);
#ifdef NOT_USED
void PrintBufferDescs(void);
@@ -127,7 +127,6 @@ ReadBufferInternal(Relation reln, BlockNumber blockNum,
bool bufferLockHeld)
{
BufferDesc *bufHdr;
int status;
bool found;
bool isExtend;
bool isLocalBuf;
@@ -135,6 +134,10 @@ ReadBufferInternal(Relation reln, BlockNumber blockNum,
isExtend = (blockNum == P_NEW);
isLocalBuf = reln->rd_istemp;
/* Open it at the smgr level if not already done */
if (reln->rd_smgr == NULL)
reln->rd_smgr = smgropen(reln->rd_node);
if (isLocalBuf)
{
ReadLocalBufferCount++;
@@ -160,7 +163,7 @@ ReadBufferInternal(Relation reln, BlockNumber blockNum,
if (isExtend)
{
/* must be sure we have accurate file length! */
blockNum = reln->rd_nblocks = smgrnblocks(DEFAULT_SMGR, reln);
blockNum = reln->rd_nblocks = smgrnblocks(reln->rd_smgr);
reln->rd_nblocks++;
}
@@ -207,23 +210,19 @@ ReadBufferInternal(Relation reln, BlockNumber blockNum,
}
/*
* if we have gotten to this point, the reln pointer must be ok and
* the relation file must be open.
* if we have gotten to this point, the relation must be open in the smgr.
*/
if (isExtend)
{
/* new buffers are zero-filled */
MemSet((char *) MAKE_PTR(bufHdr->data), 0, BLCKSZ);
status = smgrextend(DEFAULT_SMGR, reln, blockNum,
(char *) MAKE_PTR(bufHdr->data));
smgrextend(reln->rd_smgr, blockNum, (char *) MAKE_PTR(bufHdr->data));
}
else
{
status = smgrread(DEFAULT_SMGR, reln, blockNum,
(char *) MAKE_PTR(bufHdr->data));
smgrread(reln->rd_smgr, blockNum, (char *) MAKE_PTR(bufHdr->data));
/* check for garbage data */
if (status == SM_SUCCESS &&
!PageHeaderIsValid((PageHeader) MAKE_PTR(bufHdr->data)))
if (!PageHeaderIsValid((PageHeader) MAKE_PTR(bufHdr->data)))
{
/*
* During WAL recovery, the first access to any data page should
@@ -250,47 +249,20 @@ ReadBufferInternal(Relation reln, BlockNumber blockNum,
if (isLocalBuf)
{
/* No shared buffer state to update... */
if (status == SM_FAIL)
{
bufHdr->flags |= BM_IO_ERROR;
return InvalidBuffer;
}
return BufferDescriptorGetBuffer(bufHdr);
}
/* lock buffer manager again to update IO IN PROGRESS */
LWLockAcquire(BufMgrLock, LW_EXCLUSIVE);
if (status == SM_FAIL)
{
/* IO Failed. cleanup the data structures and go home */
StrategyInvalidateBuffer(bufHdr);
/* remember that BufferAlloc() pinned the buffer */
UnpinBuffer(bufHdr);
/*
* Have to reset the flag so that anyone waiting for the buffer
* can tell that the contents are invalid.
*/
bufHdr->flags |= BM_IO_ERROR;
bufHdr->flags &= ~BM_IO_IN_PROGRESS;
}
else
{
/* IO Succeeded. clear the flags, finish buffer update */
bufHdr->flags &= ~(BM_IO_ERROR | BM_IO_IN_PROGRESS);
}
/* IO Succeeded. clear the flags, finish buffer update */
bufHdr->flags &= ~(BM_IO_ERROR | BM_IO_IN_PROGRESS);
/* If anyone was waiting for IO to complete, wake them up now */
TerminateBufferIO(bufHdr);
LWLockRelease(BufMgrLock);
if (status == SM_FAIL)
return InvalidBuffer;
return BufferDescriptorGetBuffer(bufHdr);
}
@@ -391,8 +363,6 @@ BufferAlloc(Relation reln,
if (buf->flags & BM_DIRTY || buf->cntxDirty)
{
bool replace_ok;
/*
* skip write error buffers
*/
@@ -425,39 +395,21 @@ BufferAlloc(Relation reln,
* Write the buffer out, being careful to release BufMgrLock
* before starting the I/O.
*/
replace_ok = BufferReplace(buf);
BufferReplace(buf);
if (replace_ok == false)
/*
* BM_JUST_DIRTIED cleared by BufferReplace and shouldn't
* be set by anyone. - vadim 01/17/97
*/
if (buf->flags & BM_JUST_DIRTIED)
{
ereport(WARNING,
(errcode(ERRCODE_IO_ERROR),
errmsg("could not write block %u of %u/%u",
buf->tag.blockNum,
buf->tag.rnode.tblNode,
buf->tag.rnode.relNode)));
inProgress = FALSE;
buf->flags |= BM_IO_ERROR;
buf->flags &= ~BM_IO_IN_PROGRESS;
TerminateBufferIO(buf);
UnpinBuffer(buf);
buf = NULL;
elog(PANIC, "content of block %u of %u/%u changed while flushing",
buf->tag.blockNum,
buf->tag.rnode.tblNode, buf->tag.rnode.relNode);
}
else
{
/*
* BM_JUST_DIRTIED cleared by BufferReplace and shouldn't
* be set by anyone. - vadim 01/17/97
*/
if (buf->flags & BM_JUST_DIRTIED)
{
elog(PANIC, "content of block %u of %u/%u changed while flushing",
buf->tag.blockNum,
buf->tag.rnode.tblNode, buf->tag.rnode.relNode);
}
buf->flags &= ~BM_DIRTY;
buf->cntxDirty = false;
}
buf->flags &= ~BM_DIRTY;
buf->cntxDirty = false;
/*
* Somebody could have pinned the buffer while we were doing
@@ -721,10 +673,8 @@ BufferSync(int percent, int maxpages)
for (i = 0; i < num_buffer_dirty; i++)
{
Buffer buffer;
int status;
RelFileNode rnode;
XLogRecPtr recptr;
Relation reln;
SMgrRelation reln;
LWLockAcquire(BufMgrLock, LW_EXCLUSIVE);
@@ -775,15 +725,9 @@ BufferSync(int percent, int maxpages)
StartBufferIO(bufHdr, false); /* output IO start */
buffer = BufferDescriptorGetBuffer(bufHdr);
rnode = bufHdr->tag.rnode;
LWLockRelease(BufMgrLock);
/*
* Try to find relation for buffer
*/
reln = RelationNodeCacheGetRelation(rnode);
/*
* Protect buffer content against concurrent update
*/
@@ -805,27 +749,13 @@ BufferSync(int percent, int maxpages)
bufHdr->flags &= ~BM_JUST_DIRTIED;
LWLockRelease(BufMgrLock);
if (reln == NULL)
{
status = smgrblindwrt(DEFAULT_SMGR,
bufHdr->tag.rnode,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
}
else
{
status = smgrwrite(DEFAULT_SMGR, reln,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
}
/* Find smgr relation for buffer */
reln = smgropen(bufHdr->tag.rnode);
if (status == SM_FAIL) /* disk failure ?! */
ereport(PANIC,
(errcode(ERRCODE_IO_ERROR),
errmsg("could not write block %u of %u/%u",
bufHdr->tag.blockNum,
bufHdr->tag.rnode.tblNode,
bufHdr->tag.rnode.relNode)));
/* And write... */
smgrwrite(reln,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
/*
* Note that it's safe to change cntxDirty here because of we
@@ -853,10 +783,6 @@ BufferSync(int percent, int maxpages)
bufHdr->flags &= ~BM_DIRTY;
UnpinBuffer(bufHdr);
LWLockRelease(BufMgrLock);
/* drop refcnt obtained by RelationNodeCacheGetRelation */
if (reln != NULL)
RelationDecrementReferenceCount(reln);
}
pfree(buffer_dirty);
@@ -1026,12 +952,22 @@ BufferBackgroundWriter(void)
n = BufferSync(BgWriterPercent, BgWriterMaxpages);
/*
* Whatever signal is sent to us, let's just die galantly. If
* Whatever signal is sent to us, let's just die gallantly. If
* it wasn't meant that way, the postmaster will reincarnate us.
*/
if (InterruptPending)
return;
/*
* Whenever we have nothing to do, close all smgr files. This
* is so we won't hang onto smgr references to deleted files
* indefinitely. XXX this is a bogus, temporary solution. 'Twould
* be much better to do this once per checkpoint, but the bgwriter
* doesn't yet know anything about checkpoints.
*/
if (n == 0)
smgrcloseall();
/*
* Nap for the configured time or sleep for 10 seconds if
* there was nothing to do at all.
@@ -1073,17 +1009,15 @@ BufferGetBlockNumber(Buffer buffer)
/*
* BufferReplace
*
* Write out the buffer corresponding to 'bufHdr'. Returns 'true' if
* the buffer was successfully written out, 'false' otherwise.
* Write out the buffer corresponding to 'bufHdr'.
*
* BufMgrLock must be held at entry, and the buffer must be pinned.
*/
static bool
static void
BufferReplace(BufferDesc *bufHdr)
{
Relation reln;
SMgrRelation reln;
XLogRecPtr recptr;
int status;
ErrorContextCallback errcontext;
/* To check if block content changed while flushing. - vadim 01/17/97 */
@@ -1104,36 +1038,20 @@ BufferReplace(BufferDesc *bufHdr)
recptr = BufferGetLSN(bufHdr);
XLogFlush(recptr);
reln = RelationNodeCacheGetRelation(bufHdr->tag.rnode);
/* Find smgr relation for buffer */
reln = smgropen(bufHdr->tag.rnode);
if (reln != NULL)
{
status = smgrwrite(DEFAULT_SMGR, reln,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
}
else
{
status = smgrblindwrt(DEFAULT_SMGR, bufHdr->tag.rnode,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
}
/* drop relcache refcnt incremented by RelationNodeCacheGetRelation */
if (reln != NULL)
RelationDecrementReferenceCount(reln);
/* And write... */
smgrwrite(reln,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
/* Pop the error context stack */
error_context_stack = errcontext.previous;
LWLockAcquire(BufMgrLock, LW_EXCLUSIVE);
if (status == SM_FAIL)
return false;
BufferFlushCount++;
return true;
}
/*
@@ -1151,12 +1069,17 @@ RelationGetNumberOfBlocks(Relation relation)
*
* Don't call smgr on a view or a composite type, either.
*/
if (relation->rd_rel->relkind == RELKIND_VIEW)
relation->rd_nblocks = 0;
else if (relation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
if (relation->rd_rel->relkind == RELKIND_VIEW ||
relation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
relation->rd_nblocks = 0;
else if (!relation->rd_isnew && !relation->rd_istemp)
relation->rd_nblocks = smgrnblocks(DEFAULT_SMGR, relation);
{
/* Open it at the smgr level if not already done */
if (relation->rd_smgr == NULL)
relation->rd_smgr = smgropen(relation->rd_node);
relation->rd_nblocks = smgrnblocks(relation->rd_smgr);
}
return relation->rd_nblocks;
}
@@ -1172,12 +1095,17 @@ RelationGetNumberOfBlocks(Relation relation)
void
RelationUpdateNumberOfBlocks(Relation relation)
{
if (relation->rd_rel->relkind == RELKIND_VIEW)
relation->rd_nblocks = 0;
else if (relation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
if (relation->rd_rel->relkind == RELKIND_VIEW ||
relation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
relation->rd_nblocks = 0;
else
relation->rd_nblocks = smgrnblocks(DEFAULT_SMGR, relation);
{
/* Open it at the smgr level if not already done */
if (relation->rd_smgr == NULL)
relation->rd_smgr = smgropen(relation->rd_node);
relation->rd_nblocks = smgrnblocks(relation->rd_smgr);
}
}
/* ---------------------------------------------------------------------
@@ -1465,7 +1393,6 @@ FlushRelationBuffers(Relation rel, BlockNumber firstDelBlock)
int i;
BufferDesc *bufHdr;
XLogRecPtr recptr;
int status;
ErrorContextCallback errcontext;
/* Setup error traceback support for ereport() */
@@ -1484,17 +1411,13 @@ FlushRelationBuffers(Relation rel, BlockNumber firstDelBlock)
{
if (bufHdr->flags & BM_DIRTY || bufHdr->cntxDirty)
{
status = smgrwrite(DEFAULT_SMGR, rel,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
if (status == SM_FAIL)
{
error_context_stack = errcontext.previous;
elog(WARNING, "FlushRelationBuffers(\"%s\" (local), %u): block %u is dirty, could not flush it",
RelationGetRelationName(rel), firstDelBlock,
bufHdr->tag.blockNum);
return (-1);
}
/* Open it at the smgr level if not already done */
if (rel->rd_smgr == NULL)
rel->rd_smgr = smgropen(rel->rd_node);
smgrwrite(rel->rd_smgr,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
bufHdr->flags &= ~(BM_DIRTY | BM_JUST_DIRTIED);
bufHdr->cntxDirty = false;
}
@@ -1553,17 +1476,13 @@ FlushRelationBuffers(Relation rel, BlockNumber firstDelBlock)
LWLockRelease(BufMgrLock);
status = smgrwrite(DEFAULT_SMGR, rel,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
/* Open it at the smgr level if not already done */
if (rel->rd_smgr == NULL)
rel->rd_smgr = smgropen(rel->rd_node);
if (status == SM_FAIL) /* disk failure ?! */
ereport(PANIC,
(errcode(ERRCODE_IO_ERROR),
errmsg("could not write block %u of %u/%u",
bufHdr->tag.blockNum,
bufHdr->tag.rnode.tblNode,
bufHdr->tag.rnode.relNode)));
smgrwrite(rel->rd_smgr,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
BufferFlushCount++;
@@ -2046,7 +1965,11 @@ AbortBufferIO(void)
LWLockAcquire(BufMgrLock, LW_EXCLUSIVE);
Assert(buf->flags & BM_IO_IN_PROGRESS);
if (IsForInput)
{
Assert(!(buf->flags & BM_DIRTY) && !(buf->cntxDirty));
/* Don't think that buffer is valid */
StrategyInvalidateBuffer(buf);
}
else
{
Assert(buf->flags & BM_DIRTY || buf->cntxDirty);

30
src/backend/storage/buffer/localbuf.c
View File

@@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/buffer/localbuf.c,v 1.51 2004/01/07 18:56:27 neilc Exp $
* $PostgreSQL: pgsql/src/backend/storage/buffer/localbuf.c,v 1.52 2004/02/10 01:55:25 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -90,24 +90,15 @@ LocalBufferAlloc(Relation reln, BlockNumber blockNum, bool *foundPtr)
*/
if (bufHdr->flags & BM_DIRTY || bufHdr->cntxDirty)
{
Relation bufrel = RelationNodeCacheGetRelation(bufHdr->tag.rnode);
SMgrRelation reln;
/* flush this page */
if (bufrel == NULL)
{
smgrblindwrt(DEFAULT_SMGR,
bufHdr->tag.rnode,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
}
else
{
smgrwrite(DEFAULT_SMGR, bufrel,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
/* drop refcount incremented by RelationNodeCacheGetRelation */
RelationDecrementReferenceCount(bufrel);
}
/* Find smgr relation for buffer */
reln = smgropen(bufHdr->tag.rnode);
/* And write... */
smgrwrite(reln,
bufHdr->tag.blockNum,
(char *) MAKE_PTR(bufHdr->data));
LocalBufferFlushCount++;
}
@@ -143,9 +134,6 @@ LocalBufferAlloc(Relation reln, BlockNumber blockNum, bool *foundPtr)
/*
* it's all ours now.
*
* We need not in tblNode currently but will in future I think, when
* we'll give up rel->rd_fd to fmgr cache.
*/
bufHdr->tag.rnode = reln->rd_node;
bufHdr->tag.blockNum = blockNum;

5
src/backend/storage/ipc/ipci.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.63 2004/01/26 22:59:53 momjian Exp $
* $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.64 2004/02/10 01:55:25 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -65,9 +65,6 @@ CreateSharedMemoryAndSemaphores(bool makePrivate,
size += FreeSpaceShmemSize();
#ifdef EXEC_BACKEND
size += ShmemBackendArraySize();
#endif
#ifdef STABLE_MEMORY_STORAGE
size += MMShmemSize();
#endif
size += 100000;
/* might as well round it off to a multiple of a typical page size */

4
src/backend/storage/smgr/Makefile
View File

@@ -4,7 +4,7 @@
# Makefile for storage/smgr
#
# IDENTIFICATION
# $PostgreSQL: pgsql/src/backend/storage/smgr/Makefile,v 1.14 2003/11/29 19:51:57 pgsql Exp $
# $PostgreSQL: pgsql/src/backend/storage/smgr/Makefile,v 1.15 2004/02/10 01:55:26 tgl Exp $
#
#-------------------------------------------------------------------------
@@ -12,7 +12,7 @@ subdir = src/backend/storage/smgr
top_builddir = ../../../..
include $(top_builddir)/src/Makefile.global
OBJS = md.o mm.o smgr.o smgrtype.o
OBJS = md.o smgr.o smgrtype.o
all: SUBSYS.o

43
src/backend/storage/smgr/README
View File

@@ -1,40 +1,31 @@
# $PostgreSQL: pgsql/src/backend/storage/smgr/README,v 1.2 2003/11/29 19:51:57 pgsql Exp $
# $PostgreSQL: pgsql/src/backend/storage/smgr/README,v 1.3 2004/02/10 01:55:26 tgl Exp $
This directory contains the code that supports the Postgres storage manager
switch and all of the installed storage managers. In released systems,
the only supported storage manager is the magnetic disk manager. At UC
Berkeley, the Sony WORM optical disk jukebox and persistent main memory are
also supported.
In the original Berkeley Postgres system, there were several storage managers,
of which only the "magnetic disk" manager remains. (At Berkeley there were
also managers for the Sony WORM optical disk jukebox and persistent main
memory, but these were never supported in any externally released Postgres,
nor in any version of PostgreSQL.) However, we retain the notion of a storage
manager switch in case anyone wants to reintroduce other kinds of storage
managers.
As of Postgres Release 3.0, every relation in the system is tagged with the
storage manager on which it resides. The storage manager switch code turns
what used to by filesystem operations into operations on the correct store,
for any given relation.
In Berkeley Postgres each relation was tagged with the ID of the storage
manager to use for it. This is gone. It would be more reasonable to
associate storage managers with tablespaces (a feature not present as this
text is being written, but one likely to emerge soon).
The files in this directory, and their contents, are
smgrtype.c Storage manager type -- maps string names to storage manager
IDs and provides simple comparison operators. This is the
regproc support for type 'smgr' in the system catalogs.
(This is vestigial since no columns of type smgr exist
in the catalogs anymore.)
smgr.c The storage manager switch dispatch code. The routines in
this file call the appropriate storage manager to do hardware
accesses requested by the backend.
accesses requested by the backend. smgr.c also manages the
file handle cache (SMgrRelation table).
md.c The magnetic disk storage manager.
mm.c The persistent main memory storage manager (#undef'ed in
tmp/c.h for all distributed systems).
sj.c The sony jukebox storage manager and cache management code
(#undef'ed in tmp/c.h for all distributed systems). The
routines in this file allocate extents, maintain block
maps, and guarantee the persistence and coherency of a cache
of jukebox blocks on magnetic disk.
pgjb.c The postgres jukebox interface routines. The routines here
handle exclusion on the physical device and translate requests
from the storage manager code (sj.c) into jbaccess calls.
jbaccess.c Access code for the physical Sony jukebox device. This code
was swiped from Andy McFadden's jblib.a code at UC Berkeley.
Note that md.c in turn relies on src/backend/storage/file/fd.c.

526
src/backend/storage/smgr/md.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/smgr/md.c,v 1.101 2004/01/07 18:56:27 neilc Exp $
* $PostgreSQL: pgsql/src/backend/storage/smgr/md.c,v 1.102 2004/02/10 01:55:26 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -21,108 +21,81 @@
#include "catalog/catalog.h"
#include "miscadmin.h"
#include "storage/fd.h"
#include "storage/smgr.h"
#include "utils/inval.h"
#include "utils/memutils.h"
/*
* The magnetic disk storage manager keeps track of open file
* descriptors in its own descriptor pool. This is done to make it
* easier to support relations that are larger than the operating
* system's file size limit (often 2GBytes). In order to do that, we
* system's file size limit (often 2GBytes). In order to do that,
* we break relations up into chunks of < 2GBytes and store one chunk
* in each of several files that represent the relation. See the
* BLCKSZ and RELSEG_SIZE configuration constants in
* include/pg_config.h.
*
* The file descriptor stored in the relation cache (see RelationGetFile())
* is actually an index into the Md_fdvec array. -1 indicates not open.
*
* When a relation is broken into multiple chunks, only the first chunk
* has its own entry in the Md_fdvec array; the remaining chunks have
* palloc'd MdfdVec objects that are chained onto the first chunk via the
* mdfd_chain links. All chunks except the last MUST have size exactly
* include/pg_config.h. All chunks except the last MUST have size exactly
* equal to RELSEG_SIZE blocks --- see mdnblocks() and mdtruncate().
*
* The file descriptor pointer (md_fd field) stored in the SMgrRelation
* cache is, therefore, just the head of a list of MdfdVec objects.
* But note the md_fd pointer can be NULL, indicating relation not open.
*
* All MdfdVec objects are palloc'd in the MdCxt memory context.
*/
typedef struct _MdfdVec
{
int mdfd_vfd; /* fd number in vfd pool */
int mdfd_flags; /* fd status flags */
File mdfd_vfd; /* fd number in fd.c's pool */
/* these are the assigned bits in mdfd_flags: */
#define MDFD_FREE (1 << 0) /* unused entry */
int mdfd_nextFree; /* link to next freelist member, if free */
#ifndef LET_OS_MANAGE_FILESIZE
struct _MdfdVec *mdfd_chain; /* for large relations */
#endif
} MdfdVec;
static int Nfds = 100; /* initial/current size of Md_fdvec array */
static MdfdVec *Md_fdvec = NULL;
static int Md_Free = -1; /* head of freelist of unused fdvec
* entries */
static int CurFd = 0; /* first never-used fdvec index */
static MemoryContext MdCxt; /* context for all md.c allocations */
/* routines declared here */
static void mdclose_fd(int fd);
static int _mdfd_getrelnfd(Relation reln);
static MdfdVec *_mdfd_openseg(Relation reln, BlockNumber segno, int oflags);
static MdfdVec *_mdfd_getseg(Relation reln, BlockNumber blkno);
static int _mdfd_blind_getseg(RelFileNode rnode, BlockNumber blkno);
static int _fdvec_alloc(void);
static void _fdvec_free(int);
static MdfdVec *mdopen(SMgrRelation reln);
static MdfdVec *_fdvec_alloc(void);
#ifndef LET_OS_MANAGE_FILESIZE
static MdfdVec *_mdfd_openseg(SMgrRelation reln, BlockNumber segno,
int oflags);
#endif
static MdfdVec *_mdfd_getseg(SMgrRelation reln, BlockNumber blkno);
static BlockNumber _mdnblocks(File file, Size blcksz);
/*
* mdinit() -- Initialize private state for magnetic disk storage manager.
*
* We keep a private table of all file descriptors. This routine
* allocates and initializes the table.
*
* Returns SM_SUCCESS or SM_FAIL with errno set as appropriate.
*/
int
bool
mdinit(void)
{
int i;
MdCxt = AllocSetContextCreate(TopMemoryContext,
"MdSmgr",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
Md_fdvec = (MdfdVec *) MemoryContextAlloc(MdCxt, Nfds * sizeof(MdfdVec));
MemSet(Md_fdvec, 0, Nfds * sizeof(MdfdVec));
/* Set free list */
for (i = 0; i < Nfds; i++)
{
Md_fdvec[i].mdfd_nextFree = i + 1;
Md_fdvec[i].mdfd_flags = MDFD_FREE;
}
Md_Free = 0;
Md_fdvec[Nfds - 1].mdfd_nextFree = -1;
return SM_SUCCESS;
return true;
}
int
mdcreate(Relation reln)
/*
* mdcreate() -- Create a new relation on magnetic disk.
*
* If isRedo is true, it's okay for the relation to exist already.
*/
bool
mdcreate(SMgrRelation reln, bool isRedo)
{
char *path;
int fd,
vfd;
File fd;
Assert(reln->rd_fd < 0);
Assert(reln->md_fd == NULL);
path = relpath(reln->rd_node);
path = relpath(reln->smgr_rnode);
fd = FileNameOpenFile(path, O_RDWR | O_CREAT | O_EXCL | PG_BINARY, 0600);
@@ -134,43 +107,45 @@ mdcreate(Relation reln)
* During bootstrap, there are cases where a system relation will
* be accessed (by internal backend processes) before the
* bootstrap script nominally creates it. Therefore, allow the
* file to exist already, but in bootstrap mode only. (See also
* file to exist already, even if isRedo is not set. (See also
* mdopen)
*/
if (IsBootstrapProcessingMode())
if (isRedo || IsBootstrapProcessingMode())
fd = FileNameOpenFile(path, O_RDWR | PG_BINARY, 0600);
if (fd < 0)
{
pfree(path);
/* be sure to return the error reported by create, not open */
errno = save_errno;
return -1;
return false;
}
errno = 0;
}
pfree(path);
vfd = _fdvec_alloc();
if (vfd < 0)
return -1;
reln->md_fd = _fdvec_alloc();
Md_fdvec[vfd].mdfd_vfd = fd;
Md_fdvec[vfd].mdfd_flags = (uint16) 0;
reln->md_fd->mdfd_vfd = fd;
#ifndef LET_OS_MANAGE_FILESIZE
Md_fdvec[vfd].mdfd_chain = NULL;
reln->md_fd->mdfd_chain = NULL;
#endif
return vfd;
return true;
}
/*
* mdunlink() -- Unlink a relation.
*
* Note that we're passed a RelFileNode --- by the time this is called,
* there won't be an SMgrRelation hashtable entry anymore.
*
* If isRedo is true, it's okay for the relation to be already gone.
*/
int
mdunlink(RelFileNode rnode)
bool
mdunlink(RelFileNode rnode, bool isRedo)
{
int status = SM_SUCCESS;
bool status = true;
int save_errno = 0;
char *path;
@@ -179,13 +154,16 @@ mdunlink(RelFileNode rnode)
/* Delete the first segment, or only segment if not doing segmenting */
if (unlink(path) < 0)
{
status = SM_FAIL;
save_errno = errno;
if (!isRedo || errno != ENOENT)
{
status = false;
save_errno = errno;
}
}
#ifndef LET_OS_MANAGE_FILESIZE
/* Get the additional segments, if any */
if (status == SM_SUCCESS)
if (status)
{
char *segpath = (char *) palloc(strlen(path) + 12);
BlockNumber segno;
@@ -198,7 +176,7 @@ mdunlink(RelFileNode rnode)
/* ENOENT is expected after the last segment... */
if (errno != ENOENT)
{
status = SM_FAIL;
status = false;
save_errno = errno;
}
break;
@@ -222,16 +200,15 @@ mdunlink(RelFileNode rnode)
* relation (ie, blocknum is the current EOF), and so in case of
* failure we clean up by truncating.
*
* This routine returns SM_FAIL or SM_SUCCESS, with errno set as
* appropriate.
* This routine returns true or false, with errno set as appropriate.
*
* Note: this routine used to call mdnblocks() to get the block position
* to write at, but that's pretty silly since the caller needs to know where
* the block will be written, and accordingly must have done mdnblocks()
* already. Might as well pass in the position and save a seek.
*/
int
mdextend(Relation reln, BlockNumber blocknum, char *buffer)
bool
mdextend(SMgrRelation reln, BlockNumber blocknum, char *buffer)
{
long seekpos;
int nbytes;
@@ -256,7 +233,7 @@ mdextend(Relation reln, BlockNumber blocknum, char *buffer)
* to make room for the new page's buffer.
*/
if (FileSeek(v->mdfd_vfd, seekpos, SEEK_SET) != seekpos)
return SM_FAIL;
return false;
if ((nbytes = FileWrite(v->mdfd_vfd, buffer, BLCKSZ)) != BLCKSZ)
{
@@ -269,29 +246,32 @@ mdextend(Relation reln, BlockNumber blocknum, char *buffer)
FileSeek(v->mdfd_vfd, seekpos, SEEK_SET);
errno = save_errno;
}
return SM_FAIL;
return false;
}
#ifndef LET_OS_MANAGE_FILESIZE
Assert(_mdnblocks(v->mdfd_vfd, BLCKSZ) <= ((BlockNumber) RELSEG_SIZE));
#endif
return SM_SUCCESS;
return true;
}
/*
* mdopen() -- Open the specified relation.
* mdopen() -- Open the specified relation. ereport's on failure.
*
* Note we only open the first segment, when there are multiple segments.
*/
int
mdopen(Relation reln)
static MdfdVec *
mdopen(SMgrRelation reln)
{
char *path;
int fd;
int vfd;
File fd;
Assert(reln->rd_fd < 0);
/* No work if already open */
if (reln->md_fd)
return reln->md_fd;
path = relpath(reln->rd_node);
path = relpath(reln->smgr_rnode);
fd = FileNameOpenFile(path, O_RDWR | PG_BINARY, 0600);
@@ -309,57 +289,45 @@ mdopen(Relation reln)
if (fd < 0)
{
pfree(path);
return -1;
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open relation %u/%u: %m",
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode)));
}
}
pfree(path);
vfd = _fdvec_alloc();
if (vfd < 0)
return -1;
reln->md_fd = _fdvec_alloc();
Md_fdvec[vfd].mdfd_vfd = fd;
Md_fdvec[vfd].mdfd_flags = (uint16) 0;
reln->md_fd->mdfd_vfd = fd;
#ifndef LET_OS_MANAGE_FILESIZE
Md_fdvec[vfd].mdfd_chain = NULL;
reln->md_fd->mdfd_chain = NULL;
Assert(_mdnblocks(fd, BLCKSZ) <= ((BlockNumber) RELSEG_SIZE));
#endif
return vfd;
return reln->md_fd;
}
/*
* mdclose() -- Close the specified relation, if it isn't closed already.
*
* AND FREE fd vector! It may be re-used for other relations!
* reln should be flushed from cache after closing !..
*
* Returns SM_SUCCESS or SM_FAIL with errno set as appropriate.
* Returns true or false with errno set as appropriate.
*/
int
mdclose(Relation reln)
bool
mdclose(SMgrRelation reln)
{
int fd;
MdfdVec *v = reln->md_fd;
fd = RelationGetFile(reln);
if (fd < 0)
return SM_SUCCESS; /* already closed, so no work */
/* No work if already closed */
if (v == NULL)
return true;
mdclose_fd(fd);
reln->rd_fd = -1;
return SM_SUCCESS;
}
static void
mdclose_fd(int fd)
{
MdfdVec *v;
reln->md_fd = NULL; /* prevent dangling pointer after error */
#ifndef LET_OS_MANAGE_FILESIZE
for (v = &Md_fdvec[fd]; v != NULL;)
while (v != NULL)
{
MdfdVec *ov = v;
@@ -368,32 +336,24 @@ mdclose_fd(int fd)
FileClose(v->mdfd_vfd);
/* Now free vector */
v = v->mdfd_chain;
if (ov != &Md_fdvec[fd])
pfree(ov);
pfree(ov);
}
Md_fdvec[fd].mdfd_chain = NULL;
#else
v = &Md_fdvec[fd];
if (v != NULL)
{
if (v->mdfd_vfd >= 0)
FileClose(v->mdfd_vfd);
}
if (v->mdfd_vfd >= 0)
FileClose(v->mdfd_vfd);
pfree(v);
#endif
_fdvec_free(fd);
return true;
}
/*
* mdread() -- Read the specified block from a relation.
*
* Returns SM_SUCCESS or SM_FAIL.
*/
int
mdread(Relation reln, BlockNumber blocknum, char *buffer)
bool
mdread(SMgrRelation reln, BlockNumber blocknum, char *buffer)
{
int status;
bool status;
long seekpos;
int nbytes;
MdfdVec *v;
@@ -408,9 +368,9 @@ mdread(Relation reln, BlockNumber blocknum, char *buffer)
#endif
if (FileSeek(v->mdfd_vfd, seekpos, SEEK_SET) != seekpos)
return SM_FAIL;
return false;
status = SM_SUCCESS;
status = true;
if ((nbytes = FileRead(v->mdfd_vfd, buffer, BLCKSZ)) != BLCKSZ)
{
/*
@@ -425,7 +385,7 @@ mdread(Relation reln, BlockNumber blocknum, char *buffer)
(nbytes > 0 && mdnblocks(reln) == blocknum))
MemSet(buffer, 0, BLCKSZ);
else
status = SM_FAIL;
status = false;
}
return status;
@@ -433,11 +393,9 @@ mdread(Relation reln, BlockNumber blocknum, char *buffer)
/*
* mdwrite() -- Write the supplied block at the appropriate location.
*
* Returns SM_SUCCESS or SM_FAIL.
*/
int
mdwrite(Relation reln, BlockNumber blocknum, char *buffer)
bool
mdwrite(SMgrRelation reln, BlockNumber blocknum, char *buffer)
{
long seekpos;
MdfdVec *v;
@@ -452,69 +410,12 @@ mdwrite(Relation reln, BlockNumber blocknum, char *buffer)
#endif
if (FileSeek(v->mdfd_vfd, seekpos, SEEK_SET) != seekpos)
return SM_FAIL;
return false;
if (FileWrite(v->mdfd_vfd, buffer, BLCKSZ) != BLCKSZ)
return SM_FAIL;
return false;
return SM_SUCCESS;
}
/*
* mdblindwrt() -- Write a block to disk blind.
*
* We have to be able to do this using only the rnode of the relation
* in which the block belongs. Otherwise this is much like mdwrite().
*/
int
mdblindwrt(RelFileNode rnode,
BlockNumber blkno,
char *buffer)
{
int status;
long seekpos;
int fd;
fd = _mdfd_blind_getseg(rnode, blkno);
if (fd < 0)
return SM_FAIL;
#ifndef LET_OS_MANAGE_FILESIZE
seekpos = (long) (BLCKSZ * (blkno % ((BlockNumber) RELSEG_SIZE)));
Assert(seekpos < BLCKSZ * RELSEG_SIZE);
#else
seekpos = (long) (BLCKSZ * (blkno));
#endif
errno = 0;
if (lseek(fd, seekpos, SEEK_SET) != seekpos)
{
elog(LOG, "lseek(%ld) failed: %m", seekpos);
close(fd);
return SM_FAIL;
}
status = SM_SUCCESS;
/* write the block */
errno = 0;
if (write(fd, buffer, BLCKSZ) != BLCKSZ)
{
/* if write didn't set errno, assume problem is no disk space */
if (errno == 0)
errno = ENOSPC;
elog(LOG, "write() failed: %m");
status = SM_FAIL;
}
if (close(fd) < 0)
{
elog(LOG, "close() failed: %m");
status = SM_FAIL;
}
return status;
return true;
}
/*
@@ -525,24 +426,16 @@ mdblindwrt(RelFileNode rnode,
* called, then only segments up to the last one actually touched
* are present in the chain...
*
* Returns # of blocks, ereport's on error.
* Returns # of blocks, or InvalidBlockNumber on error.
*/
BlockNumber
mdnblocks(Relation reln)
mdnblocks(SMgrRelation reln)
{
int fd;
MdfdVec *v;
MdfdVec *v = mdopen(reln);
#ifndef LET_OS_MANAGE_FILESIZE
BlockNumber nblocks;
BlockNumber segno;
#endif
fd = _mdfd_getrelnfd(reln);
v = &Md_fdvec[fd];
#ifndef LET_OS_MANAGE_FILESIZE
segno = 0;
BlockNumber segno = 0;
/*
* Skip through any segments that aren't the last one, to avoid
@@ -583,8 +476,7 @@ mdnblocks(Relation reln)
*/
v->mdfd_chain = _mdfd_openseg(reln, segno, O_CREAT);
if (v->mdfd_chain == NULL)
elog(ERROR, "could not count blocks of \"%s\": %m",
RelationGetRelationName(reln));
return InvalidBlockNumber; /* failed? */
}
v = v->mdfd_chain;
@@ -600,9 +492,8 @@ mdnblocks(Relation reln)
* Returns # of blocks or InvalidBlockNumber on error.
*/
BlockNumber
mdtruncate(Relation reln, BlockNumber nblocks)
mdtruncate(SMgrRelation reln, BlockNumber nblocks)
{
int fd;
MdfdVec *v;
BlockNumber curnblk;
@@ -615,13 +506,14 @@ mdtruncate(Relation reln, BlockNumber nblocks)
* that truncate/delete loop will get them all!
*/
curnblk = mdnblocks(reln);
if (curnblk == InvalidBlockNumber)
return InvalidBlockNumber; /* mdnblocks failed */
if (nblocks > curnblk)
return InvalidBlockNumber; /* bogus request */
if (nblocks == curnblk)
return nblocks; /* no work */
fd = _mdfd_getrelnfd(reln);
v = &Md_fdvec[fd];
v = mdopen(reln);
#ifndef LET_OS_MANAGE_FILESIZE
priorblocks = 0;
@@ -641,7 +533,7 @@ mdtruncate(Relation reln, BlockNumber nblocks)
FileTruncate(v->mdfd_vfd, 0);
FileUnlink(v->mdfd_vfd);
v = v->mdfd_chain;
Assert(ov != &Md_fdvec[fd]); /* we never drop the 1st
Assert(ov != reln->md_fd); /* we never drop the 1st
* segment */
pfree(ov);
}
@@ -682,115 +574,65 @@ mdtruncate(Relation reln, BlockNumber nblocks)
/*
* mdcommit() -- Commit a transaction.
*
* Returns SM_SUCCESS or SM_FAIL with errno set as appropriate.
*/
int
bool
mdcommit(void)
{
/*
* We don't actually have to do anything here...
*/
return SM_SUCCESS;
return true;
}
/*
* mdabort() -- Abort a transaction.
*/
int
bool
mdabort(void)
{
/*
* We don't actually have to do anything here...
*/
return SM_SUCCESS;
return true;
}
/*
* mdsync() -- Sync previous writes to stable storage.
*/
int
bool
mdsync(void)
{
sync();
if (IsUnderPostmaster)
sleep(2);
sync();
return SM_SUCCESS;
return true;
}
/*
* _fdvec_alloc() -- Grab a free (or new) md file descriptor vector.
* _fdvec_alloc() -- Make a MdfdVec object.
*/
static int
static MdfdVec *
_fdvec_alloc(void)
{
MdfdVec *nvec;
int fdvec,
i;
MdfdVec *v;
if (Md_Free >= 0) /* get from free list */
{
fdvec = Md_Free;
Md_Free = Md_fdvec[fdvec].mdfd_nextFree;
Assert(Md_fdvec[fdvec].mdfd_flags == MDFD_FREE);
Md_fdvec[fdvec].mdfd_flags = 0;
if (fdvec >= CurFd)
{
Assert(fdvec == CurFd);
CurFd++;
}
return fdvec;
}
v = (MdfdVec *) MemoryContextAlloc(MdCxt, sizeof(MdfdVec));
v->mdfd_vfd = -1;
#ifndef LET_OS_MANAGE_FILESIZE
v->mdfd_chain = NULL;
#endif
/* Must allocate more room */
if (Nfds != CurFd)
elog(FATAL, "_fdvec_alloc error");
Nfds *= 2;
nvec = (MdfdVec *) MemoryContextAlloc(MdCxt, Nfds * sizeof(MdfdVec));
MemSet(nvec, 0, Nfds * sizeof(MdfdVec));
memcpy(nvec, (char *) Md_fdvec, CurFd * sizeof(MdfdVec));
pfree(Md_fdvec);
Md_fdvec = nvec;
/* Set new free list */
for (i = CurFd; i < Nfds; i++)
{
Md_fdvec[i].mdfd_nextFree = i + 1;
Md_fdvec[i].mdfd_flags = MDFD_FREE;
}
Md_fdvec[Nfds - 1].mdfd_nextFree = -1;
Md_Free = CurFd + 1;
fdvec = CurFd;
CurFd++;
Md_fdvec[fdvec].mdfd_flags = 0;
return fdvec;
return v;
}
#ifndef LET_OS_MANAGE_FILESIZE
/*
* _fdvec_free() -- free md file descriptor vector.
*
* Open the specified segment of the relation,
* and make a MdfdVec object for it. Returns NULL on failure.
*/
static
void
_fdvec_free(int fdvec)
{
Assert(Md_Free < 0 || Md_fdvec[Md_Free].mdfd_flags == MDFD_FREE);
Assert(Md_fdvec[fdvec].mdfd_flags != MDFD_FREE);
Md_fdvec[fdvec].mdfd_nextFree = Md_Free;
Md_fdvec[fdvec].mdfd_flags = MDFD_FREE;
Md_Free = fdvec;
}
static MdfdVec *
_mdfd_openseg(Relation reln, BlockNumber segno, int oflags)
_mdfd_openseg(SMgrRelation reln, BlockNumber segno, int oflags)
{
MdfdVec *v;
int fd;
@@ -798,7 +640,7 @@ _mdfd_openseg(Relation reln, BlockNumber segno, int oflags)
*fullpath;
/* be sure we have enough space for the '.segno', if any */
path = relpath(reln->rd_node);
path = relpath(reln->smgr_rnode);
if (segno > 0)
{
@@ -818,61 +660,32 @@ _mdfd_openseg(Relation reln, BlockNumber segno, int oflags)
return NULL;
/* allocate an mdfdvec entry for it */
v = (MdfdVec *) MemoryContextAlloc(MdCxt, sizeof(MdfdVec));
v = _fdvec_alloc();
/* fill the entry */
v->mdfd_vfd = fd;
v->mdfd_flags = (uint16) 0;
#ifndef LET_OS_MANAGE_FILESIZE
v->mdfd_chain = NULL;
Assert(_mdnblocks(fd, BLCKSZ) <= ((BlockNumber) RELSEG_SIZE));
#endif
/* all done */
return v;
}
/*
* _mdfd_getrelnfd() -- Get the (virtual) fd for the relation,
* opening it if it's not already open
*
*/
static int
_mdfd_getrelnfd(Relation reln)
{
int fd;
fd = RelationGetFile(reln);
if (fd < 0)
{
if ((fd = mdopen(reln)) < 0)
elog(ERROR, "could not open relation \"%s\": %m",
RelationGetRelationName(reln));
reln->rd_fd = fd;
}
return fd;
}
#endif
/*
* _mdfd_getseg() -- Find the segment of the relation holding the
* specified block
*
* specified block. ereport's on failure.
*/
static MdfdVec *
_mdfd_getseg(Relation reln, BlockNumber blkno)
_mdfd_getseg(SMgrRelation reln, BlockNumber blkno)
{
MdfdVec *v;
int fd;
MdfdVec *v = mdopen(reln);
#ifndef LET_OS_MANAGE_FILESIZE
BlockNumber segno;
BlockNumber i;
#endif
fd = _mdfd_getrelnfd(reln);
#ifndef LET_OS_MANAGE_FILESIZE
for (v = &Md_fdvec[fd], segno = blkno / ((BlockNumber) RELSEG_SIZE), i = 1;
for (segno = blkno / ((BlockNumber) RELSEG_SIZE), i = 1;
segno > 0;
i++, segno--)
{
@@ -892,65 +705,24 @@ _mdfd_getseg(Relation reln, BlockNumber blkno)
v->mdfd_chain = _mdfd_openseg(reln, i, (segno == 1) ? O_CREAT : 0);
if (v->mdfd_chain == NULL)
elog(ERROR, "could not open segment %u of relation \"%s\" (target block %u): %m",
i, RelationGetRelationName(reln), blkno);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open segment %u of relation %u/%u (target block %u): %m",
i,
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode,
blkno)));
}
v = v->mdfd_chain;
}
#else
v = &Md_fdvec[fd];
#endif
return v;
}
/*
* Find the segment of the relation holding the specified block.
*
* This performs the same work as _mdfd_getseg() except that we must work
* "blind" with no Relation struct. We assume that we are not likely to
* touch the same relation again soon, so we do not create an FD entry for
* the relation --- we just open a kernel file descriptor which will be
* used and promptly closed. We also assume that the target block already
* exists, ie, we need not extend the relation.
*
* The return value is the kernel descriptor, or -1 on failure.
* Get number of blocks present in a single disk file
*/
static int
_mdfd_blind_getseg(RelFileNode rnode, BlockNumber blkno)
{
char *path;
int fd;
#ifndef LET_OS_MANAGE_FILESIZE
BlockNumber segno;
#endif
path = relpath(rnode);
#ifndef LET_OS_MANAGE_FILESIZE
/* append the '.segno', if needed */
segno = blkno / ((BlockNumber) RELSEG_SIZE);
if (segno > 0)
{
char *segpath = (char *) palloc(strlen(path) + 12);
sprintf(segpath, "%s.%u", path, segno);
pfree(path);
path = segpath;
}
#endif
/* call fd.c to allow other FDs to be closed if needed */
fd = BasicOpenFile(path, O_RDWR | PG_BINARY, 0600);
if (fd < 0)
elog(LOG, "could not open \"%s\": %m", path);
pfree(path);
return fd;
}
static BlockNumber
_mdnblocks(File file, Size blcksz)
{

552
src/backend/storage/smgr/mm.c
View File

@@ -1,552 +0,0 @@
/*-------------------------------------------------------------------------
*
* mm.c
* main memory storage manager
*
* This code manages relations that reside in (presumably stable)
* main memory.
*
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/smgr/mm.c,v 1.36 2004/01/07 18:56:27 neilc Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <math.h>
#include "storage/smgr.h"
#include "miscadmin.h"
#ifdef STABLE_MEMORY_STORAGE
/*
* MMCacheTag -- Unique triplet for blocks stored by the main memory
* storage manager.
*/
typedef struct MMCacheTag
{
Oid mmct_dbid;
Oid mmct_relid;
BlockNumber mmct_blkno;
} MMCacheTag;
/*
* Shared-memory hash table for main memory relations contains
* entries of this form.
*/
typedef struct MMHashEntry
{
MMCacheTag mmhe_tag;
int mmhe_bufno;
} MMHashEntry;
/*
* MMRelTag -- Unique identifier for each relation that is stored in the
* main-memory storage manager.
*/
typedef struct MMRelTag
{
Oid mmrt_dbid;
Oid mmrt_relid;
} MMRelTag;
/*
* Shared-memory hash table for # blocks in main memory relations contains
* entries of this form.
*/
typedef struct MMRelHashEntry
{
MMRelTag mmrhe_tag;
int mmrhe_nblocks;
} MMRelHashEntry;
#define MMNBUFFERS 10
#define MMNRELATIONS 2
static int *MMCurTop;
static int *MMCurRelno;
static MMCacheTag *MMBlockTags;
static char *MMBlockCache;
static HTAB *MMCacheHT;
static HTAB *MMRelCacheHT;
int
mminit(void)
{
char *mmcacheblk;
int mmsize = 0;
bool found;
HASHCTL info;
LWLockAcquire(MMCacheLock, LW_EXCLUSIVE);
mmsize += MAXALIGN(BLCKSZ * MMNBUFFERS);
mmsize += MAXALIGN(sizeof(*MMCurTop));
mmsize += MAXALIGN(sizeof(*MMCurRelno));
mmsize += MAXALIGN((MMNBUFFERS * sizeof(MMCacheTag)));
mmcacheblk = (char *) ShmemInitStruct("Main memory smgr", mmsize, &found);
if (mmcacheblk == NULL)
{
LWLockRelease(MMCacheLock);
return SM_FAIL;
}
info.keysize = sizeof(MMCacheTag);
info.entrysize = sizeof(MMHashEntry);
info.hash = tag_hash;
MMCacheHT = ShmemInitHash("Main memory store HT",
MMNBUFFERS, MMNBUFFERS,
&info, (HASH_ELEM | HASH_FUNCTION));
if (MMCacheHT == NULL)
{
LWLockRelease(MMCacheLock);
return SM_FAIL;
}
info.keysize = sizeof(MMRelTag);
info.entrysize = sizeof(MMRelHashEntry);
info.hash = tag_hash;
MMRelCacheHT = ShmemInitHash("Main memory rel HT",
MMNRELATIONS, MMNRELATIONS,
&info, (HASH_ELEM | HASH_FUNCTION));
if (MMRelCacheHT == NULL)
{
LWLockRelease(MMCacheLock);
return SM_FAIL;
}
if (IsUnderPostmaster) /* was IsPostmaster bjm */
{
MemSet(mmcacheblk, 0, mmsize);
LWLockRelease(MMCacheLock);
return SM_SUCCESS;
}
LWLockRelease(MMCacheLock);
MMCurTop = (int *) mmcacheblk;
mmcacheblk += sizeof(int);
MMCurRelno = (int *) mmcacheblk;
mmcacheblk += sizeof(int);
MMBlockTags = (MMCacheTag *) mmcacheblk;
mmcacheblk += (MMNBUFFERS * sizeof(MMCacheTag));
MMBlockCache = mmcacheblk;
return SM_SUCCESS;
}
int
mmshutdown(void)
{
return SM_SUCCESS;
}
int
mmcreate(Relation reln)
{
MMRelHashEntry *entry;
bool found;
MMRelTag tag;
LWLockAcquire(MMCacheLock, LW_EXCLUSIVE);
if (*MMCurRelno == MMNRELATIONS)
{
LWLockRelease(MMCacheLock);
return SM_FAIL;
}
(*MMCurRelno)++;
tag.mmrt_relid = RelationGetRelid(reln);
if (reln->rd_rel->relisshared)
tag.mmrt_dbid = (Oid) 0;
else
tag.mmrt_dbid = MyDatabaseId;
entry = (MMRelHashEntry *) hash_search(MMRelCacheHT,
(void *) &tag,
HASH_ENTER, &found);
if (entry == NULL)
{
LWLockRelease(MMCacheLock);
ereport(FATAL,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of memory")));
}
if (found)
{
/* already exists */
LWLockRelease(MMCacheLock);
return SM_FAIL;
}
entry->mmrhe_nblocks = 0;
LWLockRelease(MMCacheLock);
return SM_SUCCESS;
}
/*
* mmunlink() -- Unlink a relation.
*
* XXX currently broken: needs to accept RelFileNode, not Relation
*/
int
mmunlink(RelFileNode rnode)
{
int i;
MMHashEntry *entry;
MMRelHashEntry *rentry;
MMRelTag rtag;
LWLockAcquire(MMCacheLock, LW_EXCLUSIVE);
for (i = 0; i < MMNBUFFERS; i++)
{
if (MMBlockTags[i].mmct_dbid == rnode.tblNode
&& MMBlockTags[i].mmct_relid == rnode.relNode)
{
entry = (MMHashEntry *) hash_search(MMCacheHT,
(void *) &MMBlockTags[i],
HASH_REMOVE, NULL);
if (entry == NULL)
{
LWLockRelease(MMCacheLock);
elog(FATAL, "cache hash table corrupted");
}
MMBlockTags[i].mmct_dbid = (Oid) 0;
MMBlockTags[i].mmct_relid = (Oid) 0;
MMBlockTags[i].mmct_blkno = (BlockNumber) 0;
}
}
rtag.mmrt_dbid = rnode.tblNode;
rtag.mmrt_relid = rnode.relNode;
rentry = (MMRelHashEntry *) hash_search(MMRelCacheHT,
(void *) &rtag,
HASH_REMOVE, NULL);
if (rentry == NULL)
{
LWLockRelease(MMCacheLock);
elog(FATAL, "rel cache hash table corrupted");
}
(*MMCurRelno)--;
LWLockRelease(MMCacheLock);
return 1;
}
/*
* mmextend() -- Add a block to the specified relation.
*
* This routine returns SM_FAIL or SM_SUCCESS, with errno set as
* appropriate.
*/
int
mmextend(Relation reln, BlockNumber blocknum, char *buffer)
{
MMRelHashEntry *rentry;
MMHashEntry *entry;
int i;
Oid reldbid;
int offset;
bool found;
MMRelTag rtag;
MMCacheTag tag;
if (reln->rd_rel->relisshared)
reldbid = (Oid) 0;
else
reldbid = MyDatabaseId;
tag.mmct_dbid = rtag.mmrt_dbid = reldbid;
tag.mmct_relid = rtag.mmrt_relid = RelationGetRelid(reln);
LWLockAcquire(MMCacheLock, LW_EXCLUSIVE);
if (*MMCurTop == MMNBUFFERS)
{
for (i = 0; i < MMNBUFFERS; i++)
{
if (MMBlockTags[i].mmct_dbid == 0 &&
MMBlockTags[i].mmct_relid == 0)
break;
}
if (i == MMNBUFFERS)
{
LWLockRelease(MMCacheLock);
return SM_FAIL;
}
}
else
{
i = *MMCurTop;
(*MMCurTop)++;
}
rentry = (MMRelHashEntry *) hash_search(MMRelCacheHT,
(void *) &rtag,
HASH_FIND, NULL);
if (rentry == NULL)
{
LWLockRelease(MMCacheLock);
elog(FATAL, "rel cache hash table corrupted");
}
tag.mmct_blkno = rentry->mmrhe_nblocks;
entry = (MMHashEntry *) hash_search(MMCacheHT,
(void *) &tag,
HASH_ENTER, &found);
if (entry == NULL || found)
{
LWLockRelease(MMCacheLock);
elog(FATAL, "cache hash table corrupted");
}
entry->mmhe_bufno = i;
MMBlockTags[i].mmct_dbid = reldbid;
MMBlockTags[i].mmct_relid = RelationGetRelid(reln);
MMBlockTags[i].mmct_blkno = rentry->mmrhe_nblocks;
/* page numbers are zero-based, so we increment this at the end */
(rentry->mmrhe_nblocks)++;
/* write the extended page */
offset = (i * BLCKSZ);
memmove(&(MMBlockCache[offset]), buffer, BLCKSZ);
LWLockRelease(MMCacheLock);
return SM_SUCCESS;
}
/*
* mmopen() -- Open the specified relation.
*/
int
mmopen(Relation reln)
{
/* automatically successful */
return 0;
}
/*
* mmclose() -- Close the specified relation.
*
* Returns SM_SUCCESS or SM_FAIL with errno set as appropriate.
*/
int
mmclose(Relation reln)
{
/* automatically successful */
return SM_SUCCESS;
}
/*
* mmread() -- Read the specified block from a relation.
*
* Returns SM_SUCCESS or SM_FAIL.
*/
int
mmread(Relation reln, BlockNumber blocknum, char *buffer)
{
MMHashEntry *entry;
int offset;
MMCacheTag tag;
if (reln->rd_rel->relisshared)
tag.mmct_dbid = (Oid) 0;
else
tag.mmct_dbid = MyDatabaseId;
tag.mmct_relid = RelationGetRelid(reln);
tag.mmct_blkno = blocknum;
LWLockAcquire(MMCacheLock, LW_EXCLUSIVE);
entry = (MMHashEntry *) hash_search(MMCacheHT,
(void *) &tag,
HASH_FIND, NULL);
if (entry == NULL)
{
/* reading nonexistent pages is defined to fill them with zeroes */
LWLockRelease(MMCacheLock);
MemSet(buffer, 0, BLCKSZ);
return SM_SUCCESS;
}
offset = (entry->mmhe_bufno * BLCKSZ);
memmove(buffer, &MMBlockCache[offset], BLCKSZ);
LWLockRelease(MMCacheLock);
return SM_SUCCESS;
}
/*
* mmwrite() -- Write the supplied block at the appropriate location.
*
* Returns SM_SUCCESS or SM_FAIL.
*/
int
mmwrite(Relation reln, BlockNumber blocknum, char *buffer)
{
MMHashEntry *entry;
int offset;
MMCacheTag tag;
if (reln->rd_rel->relisshared)
tag.mmct_dbid = (Oid) 0;
else
tag.mmct_dbid = MyDatabaseId;
tag.mmct_relid = RelationGetRelid(reln);
tag.mmct_blkno = blocknum;
LWLockAcquire(MMCacheLock, LW_EXCLUSIVE);
entry = (MMHashEntry *) hash_search(MMCacheHT,
(void *) &tag,
HASH_FIND, NULL);
if (entry == NULL)
{
LWLockRelease(MMCacheLock);
elog(FATAL, "cache hash table missing requested page");
}
offset = (entry->mmhe_bufno * BLCKSZ);
memmove(&MMBlockCache[offset], buffer, BLCKSZ);
LWLockRelease(MMCacheLock);
return SM_SUCCESS;
}
/*
* mmblindwrt() -- Write a block to stable storage blind.
*
* We have to be able to do this using only the rnode of the relation
* in which the block belongs. Otherwise this is much like mmwrite().
*/
int
mmblindwrt(RelFileNode rnode,
BlockNumber blkno,
char *buffer)
{
return SM_FAIL;
}
/*
* mmnblocks() -- Get the number of blocks stored in a relation.
*
* Returns # of blocks or InvalidBlockNumber on error.
*/
BlockNumber
mmnblocks(Relation reln)
{
MMRelTag rtag;
MMRelHashEntry *rentry;
BlockNumber nblocks;
if (reln->rd_rel->relisshared)
rtag.mmrt_dbid = (Oid) 0;
else
rtag.mmrt_dbid = MyDatabaseId;
rtag.mmrt_relid = RelationGetRelid(reln);
LWLockAcquire(MMCacheLock, LW_EXCLUSIVE);
rentry = (MMRelHashEntry *) hash_search(MMRelCacheHT,
(void *) &rtag,
HASH_FIND, NULL);
if (rentry)
nblocks = rentry->mmrhe_nblocks;
else
nblocks = InvalidBlockNumber;
LWLockRelease(MMCacheLock);
return nblocks;
}
/*
* mmcommit() -- Commit a transaction.
*
* Returns SM_SUCCESS or SM_FAIL with errno set as appropriate.
*/
int
mmcommit(void)
{
return SM_SUCCESS;
}
/*
* mmabort() -- Abort a transaction.
*/
int
mmabort(void)
{
return SM_SUCCESS;
}
/*
* MMShmemSize() -- Declare amount of shared memory we require.
*
* The shared memory initialization code creates a block of shared
* memory exactly big enough to hold all the structures it needs to.
* This routine declares how much space the main memory storage
* manager will use.
*/
int
MMShmemSize(void)
{
int size = 0;
/*
* first compute space occupied by the (dbid,relid,blkno) hash table
*/
size += hash_estimate_size(MMNBUFFERS, sizeof(MMHashEntry));
/*
* now do the same for the rel hash table
*/
size += hash_estimate_size(MMNRELATIONS, sizeof(MMRelHashEntry));
/*
* finally, add in the memory block we use directly
*/
size += MAXALIGN(BLCKSZ * MMNBUFFERS);
size += MAXALIGN(sizeof(*MMCurTop));
size += MAXALIGN(sizeof(*MMCurRelno));
size += MAXALIGN(MMNBUFFERS * sizeof(MMCacheTag));
return size;
}
#endif /* STABLE_MEMORY_STORAGE */

576
src/backend/storage/smgr/smgr.c
View File

@@ -11,7 +11,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/smgr/smgr.c,v 1.68 2004/01/06 18:07:31 neilc Exp $
* $PostgreSQL: pgsql/src/backend/storage/smgr/smgr.c,v 1.69 2004/02/10 01:55:26 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -21,72 +21,52 @@
#include "storage/freespace.h"
#include "storage/ipc.h"
#include "storage/smgr.h"
#include "utils/hsearch.h"
#include "utils/memutils.h"
static void smgrshutdown(int code, Datum arg);
/*
* This struct of function pointers defines the API between smgr.c and
* any individual storage manager module. Note that smgr subfunctions are
* generally expected to return TRUE on success, FALSE on error. (For
* nblocks and truncate we instead say that returning InvalidBlockNumber
* indicates an error.)
*/
typedef struct f_smgr
{
int (*smgr_init) (void); /* may be NULL */
int (*smgr_shutdown) (void); /* may be NULL */
int (*smgr_create) (Relation reln);
int (*smgr_unlink) (RelFileNode rnode);
int (*smgr_extend) (Relation reln, BlockNumber blocknum,
bool (*smgr_init) (void); /* may be NULL */
bool (*smgr_shutdown) (void); /* may be NULL */
bool (*smgr_close) (SMgrRelation reln);
bool (*smgr_create) (SMgrRelation reln, bool isRedo);
bool (*smgr_unlink) (RelFileNode rnode, bool isRedo);
bool (*smgr_extend) (SMgrRelation reln, BlockNumber blocknum,
char *buffer);
int (*smgr_open) (Relation reln);
int (*smgr_close) (Relation reln);
int (*smgr_read) (Relation reln, BlockNumber blocknum,
bool (*smgr_read) (SMgrRelation reln, BlockNumber blocknum,
char *buffer);
int (*smgr_write) (Relation reln, BlockNumber blocknum,
bool (*smgr_write) (SMgrRelation reln, BlockNumber blocknum,
char *buffer);
int (*smgr_blindwrt) (RelFileNode rnode, BlockNumber blkno,
char *buffer);
BlockNumber (*smgr_nblocks) (Relation reln);
BlockNumber (*smgr_truncate) (Relation reln, BlockNumber nblocks);
int (*smgr_commit) (void); /* may be NULL */
int (*smgr_abort) (void); /* may be NULL */
int (*smgr_sync) (void);
BlockNumber (*smgr_nblocks) (SMgrRelation reln);
BlockNumber (*smgr_truncate) (SMgrRelation reln, BlockNumber nblocks);
bool (*smgr_commit) (void); /* may be NULL */
bool (*smgr_abort) (void); /* may be NULL */
bool (*smgr_sync) (void); /* may be NULL */
} f_smgr;
/*
* The weird placement of commas in this init block is to keep the compiler
* happy, regardless of what storage managers we have (or don't have).
*/
static f_smgr smgrsw[] = {
static const f_smgr smgrsw[] = {
/* magnetic disk */
{mdinit, NULL, mdcreate, mdunlink, mdextend, mdopen, mdclose,
mdread, mdwrite, mdblindwrt,
mdnblocks, mdtruncate, mdcommit, mdabort, mdsync
},
#ifdef STABLE_MEMORY_STORAGE
/* main memory */
{mminit, mmshutdown, mmcreate, mmunlink, mmextend, mmopen, mmclose,
mmread, mmwrite, mmblindwrt,
mmnblocks, NULL, mmcommit, mmabort, NULL},
#endif
{mdinit, NULL, mdclose, mdcreate, mdunlink, mdextend,
mdread, mdwrite, mdnblocks, mdtruncate, mdcommit, mdabort, mdsync
}
};
static const int NSmgr = lengthof(smgrsw);
/*
* This array records which storage managers are write-once, and which
* support overwrite. A 'true' entry means that the storage manager is
* write-once. In the best of all possible worlds, there would be no
* write-once storage managers.
* Each backend has a hashtable that stores all extant SMgrRelation objects.
*/
#ifdef NOT_USED
static bool smgrwo[] = {
false, /* magnetic disk */
#ifdef STABLE_MEMORY_STORAGE
false, /* main memory */
#endif
};
#endif
static int NSmgr = lengthof(smgrsw);
static HTAB *SMgrRelationHash = NULL;
/*
* We keep a list of all relations (represented as RelFileNode values)
@@ -105,7 +85,7 @@ static int NSmgr = lengthof(smgrsw);
typedef struct PendingRelDelete
{
RelFileNode relnode; /* relation that may need to be deleted */
int16 which; /* which storage manager? */
int which; /* which storage manager? */
bool isTemp; /* is it a temporary relation? */
bool atCommit; /* T=delete at commit; F=delete at abort */
struct PendingRelDelete *next; /* linked-list link */
@@ -114,12 +94,20 @@ typedef struct PendingRelDelete
static PendingRelDelete *pendingDeletes = NULL; /* head of linked list */
/* local function prototypes */
static void smgrshutdown(int code, Datum arg);
static void smgr_internal_unlink(RelFileNode rnode, int which,
bool isTemp, bool isRedo);
/*
* smgrinit(), smgrshutdown() -- Initialize or shut down all storage
* managers.
*
* Note: in the normal multiprocess scenario with a postmaster, these are
* called at postmaster start and stop, not per-backend.
*/
int
void
smgrinit(void)
{
int i;
@@ -128,7 +116,7 @@ smgrinit(void)
{
if (smgrsw[i].smgr_init)
{
if ((*(smgrsw[i].smgr_init)) () == SM_FAIL)
if (! (*(smgrsw[i].smgr_init)) ())
elog(FATAL, "smgr initialization failed on %s: %m",
DatumGetCString(DirectFunctionCall1(smgrout,
Int16GetDatum(i))));
@@ -137,8 +125,6 @@ smgrinit(void)
/* register the shutdown proc */
on_proc_exit(smgrshutdown, 0);
return SM_SUCCESS;
}
static void
@@ -150,7 +136,7 @@ smgrshutdown(int code, Datum arg)
{
if (smgrsw[i].smgr_shutdown)
{
if ((*(smgrsw[i].smgr_shutdown)) () == SM_FAIL)
if (! (*(smgrsw[i].smgr_shutdown)) ())
elog(FATAL, "smgr shutdown failed on %s: %m",
DatumGetCString(DirectFunctionCall1(smgrout,
Int16GetDatum(i))));
@@ -159,57 +145,177 @@ smgrshutdown(int code, Datum arg)
}
/*
* smgrcreate() -- Create a new relation.
* smgropen() -- Return an SMgrRelation object, creating it if need be.
*
* This routine takes a reldesc, creates the relation on the appropriate
* device, and returns a file descriptor for it.
* This does not attempt to actually open the object.
*/
int
smgrcreate(int16 which, Relation reln)
SMgrRelation
smgropen(RelFileNode rnode)
{
int fd;
PendingRelDelete *pending;
SMgrRelation reln;
bool found;
if ((fd = (*(smgrsw[which].smgr_create)) (reln)) < 0)
if (SMgrRelationHash == NULL)
{
/* First time through: initialize the hash table */
HASHCTL ctl;
MemSet(&ctl, 0, sizeof(ctl));
ctl.keysize = sizeof(RelFileNode);
ctl.entrysize = sizeof(SMgrRelationData);
ctl.hash = tag_hash;
SMgrRelationHash = hash_create("smgr relation table", 400,
&ctl, HASH_ELEM | HASH_FUNCTION);
}
/* Look up or create an entry */
reln = (SMgrRelation) hash_search(SMgrRelationHash,
(void *) &rnode,
HASH_ENTER, &found);
if (reln == NULL)
ereport(ERROR,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of memory")));
/* Initialize it if not present before */
if (!found)
{
/* hash_search already filled in the lookup key */
reln->smgr_which = 0; /* we only have md.c at present */
reln->md_fd = NULL; /* mark it not open */
}
return reln;
}
/*
* smgrclose() -- Close and delete an SMgrRelation object.
*
* It is the caller's responsibility not to leave any dangling references
* to the object. (Pointers should be cleared after successful return;
* on the off chance of failure, the SMgrRelation object will still exist.)
*/
void
smgrclose(SMgrRelation reln)
{
if (! (*(smgrsw[reln->smgr_which].smgr_close)) (reln))
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not create relation \"%s\": %m",
RelationGetRelationName(reln))));
errmsg("could not close relation %u/%u: %m",
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode)));
if (hash_search(SMgrRelationHash,
(void *) &(reln->smgr_rnode),
HASH_REMOVE, NULL) == NULL)
elog(ERROR, "SMgrRelation hashtable corrupted");
}
/*
* smgrcloseall() -- Close all existing SMgrRelation objects.
*
* It is the caller's responsibility not to leave any dangling references.
*/
void
smgrcloseall(void)
{
HASH_SEQ_STATUS status;
SMgrRelation reln;
/* Nothing to do if hashtable not set up */
if (SMgrRelationHash == NULL)
return;
hash_seq_init(&status, SMgrRelationHash);
while ((reln = (SMgrRelation) hash_seq_search(&status)) != NULL)
{
smgrclose(reln);
}
}
/*
* smgrclosenode() -- Close SMgrRelation object for given RelFileNode,
* if one exists.
*
* This has the same effects as smgrclose(smgropen(rnode)), but it avoids
* uselessly creating a hashtable entry only to drop it again when no
* such entry exists already.
*
* It is the caller's responsibility not to leave any dangling references.
*/
void
smgrclosenode(RelFileNode rnode)
{
SMgrRelation reln;
/* Nothing to do if hashtable not set up */
if (SMgrRelationHash == NULL)
return;
reln = (SMgrRelation) hash_search(SMgrRelationHash,
(void *) &rnode,
HASH_FIND, NULL);
if (reln != NULL)
smgrclose(reln);
}
/*
* smgrcreate() -- Create a new relation.
*
* Given an already-created (but presumably unused) SMgrRelation,
* cause the underlying disk file or other storage to be created.
*
* If isRedo is true, it is okay for the underlying file to exist
* already because we are in a WAL replay sequence. In this case
* we should make no PendingRelDelete entry; the WAL sequence will
* tell whether to drop the file.
*/
void
smgrcreate(SMgrRelation reln, bool isTemp, bool isRedo)
{
PendingRelDelete *pending;
if (! (*(smgrsw[reln->smgr_which].smgr_create)) (reln, isRedo))
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not create relation %u/%u: %m",
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode)));
if (isRedo)
return;
/* Add the relation to the list of stuff to delete at abort */
pending = (PendingRelDelete *)
MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
pending->relnode = reln->rd_node;
pending->which = which;
pending->isTemp = reln->rd_istemp;
pending->relnode = reln->smgr_rnode;
pending->which = reln->smgr_which;
pending->isTemp = isTemp;
pending->atCommit = false; /* delete if abort */
pending->next = pendingDeletes;
pendingDeletes = pending;
return fd;
}
/*
* smgrunlink() -- Unlink a relation.
* smgrscheduleunlink() -- Schedule unlinking a relation at xact commit.
*
* The relation is removed from the store. Actually, we just remember
* that we want to do this at transaction commit.
* The relation is marked to be removed from the store if we
* successfully commit the current transaction.
*
* This also implies smgrclose() on the SMgrRelation object.
*/
int
smgrunlink(int16 which, Relation reln)
void
smgrscheduleunlink(SMgrRelation reln, bool isTemp)
{
PendingRelDelete *pending;
/* Make sure the file is closed */
if (reln->rd_fd >= 0)
smgrclose(which, reln);
/* Add the relation to the list of stuff to delete at commit */
pending = (PendingRelDelete *)
MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
pending->relnode = reln->rd_node;
pending->which = which;
pending->isTemp = reln->rd_istemp;
pending->relnode = reln->smgr_rnode;
pending->which = reln->smgr_which;
pending->isTemp = isTemp;
pending->atCommit = true; /* delete if commit */
pending->next = pendingDeletes;
pendingDeletes = pending;
@@ -224,7 +330,63 @@ smgrunlink(int16 which, Relation reln)
* immediately, but for now I'll keep the logic simple.
*/
return SM_SUCCESS;
/* Now close the file and throw away the hashtable entry */
smgrclose(reln);
}
/*
* smgrdounlink() -- Immediately unlink a relation.
*
* The relation is removed from the store. This should not be used
* during transactional operations, since it can't be undone.
*
* If isRedo is true, it is okay for the underlying file to be gone
* already. (In practice isRedo will always be true.)
*
* This also implies smgrclose() on the SMgrRelation object.
*/
void
smgrdounlink(SMgrRelation reln, bool isTemp, bool isRedo)
{
RelFileNode rnode = reln->smgr_rnode;
int which = reln->smgr_which;
/* Close the file and throw away the hashtable entry */
smgrclose(reln);
smgr_internal_unlink(rnode, which, isTemp, isRedo);
}
/*
* Shared subroutine that actually does the unlink ...
*/
static void
smgr_internal_unlink(RelFileNode rnode, int which, bool isTemp, bool isRedo)
{
/*
* Get rid of any leftover buffers for the rel (shouldn't be any in the
* commit case, but there can be in the abort case).
*/
DropRelFileNodeBuffers(rnode, isTemp);
/*
* Tell the free space map to forget this relation. It won't be accessed
* any more anyway, but we may as well recycle the map space quickly.
*/
FreeSpaceMapForgetRel(&rnode);
/*
* And delete the physical files.
*
* Note: we treat deletion failure as a WARNING, not an error,
* because we've already decided to commit or abort the current xact.
*/
if (! (*(smgrsw[which].smgr_unlink)) (rnode, isRedo))
ereport(WARNING,
(errcode_for_file_access(),
errmsg("could not unlink relation %u/%u: %m",
rnode.tblNode,
rnode.relNode)));
}
/*
@@ -234,68 +396,17 @@ smgrunlink(int16 which, Relation reln)
* specified position. However, we are expecting to extend the
* relation (ie, blocknum is the current EOF), and so in case of
* failure we clean up by truncating.
*
* Returns SM_SUCCESS on success; aborts the current transaction on
* failure.
*/
int
smgrextend(int16 which, Relation reln, BlockNumber blocknum, char *buffer)
void
smgrextend(SMgrRelation reln, BlockNumber blocknum, char *buffer)
{
int status;
status = (*(smgrsw[which].smgr_extend)) (reln, blocknum, buffer);
if (status == SM_FAIL)
if (! (*(smgrsw[reln->smgr_which].smgr_extend)) (reln, blocknum, buffer))
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not extend relation \"%s\": %m",
RelationGetRelationName(reln)),
errmsg("could not extend relation %u/%u: %m",
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode),
errhint("Check free disk space.")));
return status;
}
/*
* smgropen() -- Open a relation using a particular storage manager.
*
* Returns the fd for the open relation on success.
*
* On failure, returns -1 if failOK, else aborts the transaction.
*/
int
smgropen(int16 which, Relation reln, bool failOK)
{
int fd;
if (reln->rd_rel->relkind == RELKIND_VIEW)
return -1;
if (reln->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
return -1;
if ((fd = (*(smgrsw[which].smgr_open)) (reln)) < 0)
if (!failOK)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open file \"%s\": %m",
RelationGetRelationName(reln))));
return fd;
}
/*
* smgrclose() -- Close a relation.
*
* Returns SM_SUCCESS on success, aborts on failure.
*/
int
smgrclose(int16 which, Relation reln)
{
if ((*(smgrsw[which].smgr_close)) (reln) == SM_FAIL)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not close relation \"%s\": %m",
RelationGetRelationName(reln))));
return SM_SUCCESS;
}
/*
@@ -304,24 +415,18 @@ smgrclose(int16 which, Relation reln)
*
* This routine is called from the buffer manager in order to
* instantiate pages in the shared buffer cache. All storage managers
* return pages in the format that POSTGRES expects. This routine
* dispatches the read. On success, it returns SM_SUCCESS. On failure,
* the current transaction is aborted.
* return pages in the format that POSTGRES expects.
*/
int
smgrread(int16 which, Relation reln, BlockNumber blocknum, char *buffer)
void
smgrread(SMgrRelation reln, BlockNumber blocknum, char *buffer)
{
int status;
status = (*(smgrsw[which].smgr_read)) (reln, blocknum, buffer);
if (status == SM_FAIL)
if (! (*(smgrsw[reln->smgr_which].smgr_read)) (reln, blocknum, buffer))
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not read block %d of relation \"%s\": %m",
blocknum, RelationGetRelationName(reln))));
return status;
errmsg("could not read block %u of relation %u/%u: %m",
blocknum,
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode)));
}
/*
@@ -329,56 +434,17 @@ smgrread(int16 which, Relation reln, BlockNumber blocknum, char *buffer)
*
* This is not a synchronous write -- the block is not necessarily
* on disk at return, only dumped out to the kernel.
*
* The buffer is written out via the appropriate
* storage manager. This routine returns SM_SUCCESS or aborts
* the current transaction.
*/
int
smgrwrite(int16 which, Relation reln, BlockNumber blocknum, char *buffer)
void
smgrwrite(SMgrRelation reln, BlockNumber blocknum, char *buffer)
{
int status;
status = (*(smgrsw[which].smgr_write)) (reln, blocknum, buffer);
if (status == SM_FAIL)
if (! (*(smgrsw[reln->smgr_which].smgr_write)) (reln, blocknum, buffer))
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write block %d of relation \"%s\": %m",
blocknum, RelationGetRelationName(reln))));
return status;
}
/*
* smgrblindwrt() -- Write a page out blind.
*
* In some cases, we may find a page in the buffer cache that we
* can't make a reldesc for. This happens, for example, when we
* want to reuse a dirty page that was written by a transaction
* that has not yet committed, which created a new relation. In
* this case, the buffer manager will call smgrblindwrt() with
* the name and OID of the database and the relation to which the
* buffer belongs. Every storage manager must be able to write
* this page out to stable storage in this circumstance.
*/
int
smgrblindwrt(int16 which,
RelFileNode rnode,
BlockNumber blkno,
char *buffer)
{
int status;
status = (*(smgrsw[which].smgr_blindwrt)) (rnode, blkno, buffer);
if (status == SM_FAIL)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write block %d of %u/%u blind: %m",
blkno, rnode.tblNode, rnode.relNode)));
return status;
errmsg("could not write block %u of relation %u/%u: %m",
blocknum,
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode)));
}
/*
@@ -389,11 +455,11 @@ smgrblindwrt(int16 which,
* transaction on failure.
*/
BlockNumber
smgrnblocks(int16 which, Relation reln)
smgrnblocks(SMgrRelation reln)
{
BlockNumber nblocks;
nblocks = (*(smgrsw[which].smgr_nblocks)) (reln);
nblocks = (*(smgrsw[reln->smgr_which].smgr_nblocks)) (reln);
/*
* NOTE: if a relation ever did grow to 2^32-1 blocks, this code would
@@ -404,8 +470,9 @@ smgrnblocks(int16 which, Relation reln)
if (nblocks == InvalidBlockNumber)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not count blocks of relation \"%s\": %m",
RelationGetRelationName(reln))));
errmsg("could not count blocks of relation %u/%u: %m",
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode)));
return nblocks;
}
@@ -418,27 +485,25 @@ smgrnblocks(int16 which, Relation reln)
* transaction on failure.
*/
BlockNumber
smgrtruncate(int16 which, Relation reln, BlockNumber nblocks)
smgrtruncate(SMgrRelation reln, BlockNumber nblocks)
{
BlockNumber newblks;
newblks = nblocks;
if (smgrsw[which].smgr_truncate)
{
/*
* 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->rd_node, nblocks);
/*
* 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, nblocks);
newblks = (*(smgrsw[which].smgr_truncate)) (reln, nblocks);
if (newblks == InvalidBlockNumber)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not truncate relation \"%s\" to %u blocks: %m",
RelationGetRelationName(reln), nblocks)));
}
newblks = (*(smgrsw[reln->smgr_which].smgr_truncate)) (reln, nblocks);
if (newblks == InvalidBlockNumber)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not truncate relation %u/%u to %u blocks: %m",
reln->smgr_rnode.tblNode,
reln->smgr_rnode.relNode,
nblocks)));
return newblks;
}
@@ -446,7 +511,7 @@ smgrtruncate(int16 which, Relation reln, BlockNumber nblocks)
/*
* smgrDoPendingDeletes() -- Take care of relation deletes at end of xact.
*/
int
void
smgrDoPendingDeletes(bool isCommit)
{
while (pendingDeletes != NULL)
@@ -455,39 +520,12 @@ smgrDoPendingDeletes(bool isCommit)
pendingDeletes = pending->next;
if (pending->atCommit == isCommit)
{
/*
* Get rid of any leftover buffers for the rel (shouldn't be
* any in the commit case, but there can be in the abort
* case).
*/
DropRelFileNodeBuffers(pending->relnode, pending->isTemp);
/*
* Tell the free space map to forget this relation. It won't
* be accessed any more anyway, but we may as well recycle the
* map space quickly.
*/
FreeSpaceMapForgetRel(&pending->relnode);
/*
* And delete the physical files.
*
* Note: we treat deletion failure as a WARNING, not an error,
* because we've already decided to commit or abort the
* current xact.
*/
if ((*(smgrsw[pending->which].smgr_unlink)) (pending->relnode) == SM_FAIL)
ereport(WARNING,
(errcode_for_file_access(),
errmsg("could not unlink %u/%u: %m",
pending->relnode.tblNode,
pending->relnode.relNode)));
}
smgr_internal_unlink(pending->relnode,
pending->which,
pending->isTemp,
false);
pfree(pending);
}
return SM_SUCCESS;
}
/*
@@ -496,7 +534,7 @@ smgrDoPendingDeletes(bool isCommit)
*
* This is called before we actually commit.
*/
int
void
smgrcommit(void)
{
int i;
@@ -505,20 +543,18 @@ smgrcommit(void)
{
if (smgrsw[i].smgr_commit)
{
if ((*(smgrsw[i].smgr_commit)) () == SM_FAIL)
if (! (*(smgrsw[i].smgr_commit)) ())
elog(FATAL, "transaction commit failed on %s: %m",
DatumGetCString(DirectFunctionCall1(smgrout,
Int16GetDatum(i))));
}
}
return SM_SUCCESS;
}
/*
* smgrabort() -- Abort changes made during the current transaction.
*/
int
void
smgrabort(void)
{
int i;
@@ -527,20 +563,18 @@ smgrabort(void)
{
if (smgrsw[i].smgr_abort)
{
if ((*(smgrsw[i].smgr_abort)) () == SM_FAIL)
if (! (*(smgrsw[i].smgr_abort)) ())
elog(FATAL, "transaction abort failed on %s: %m",
DatumGetCString(DirectFunctionCall1(smgrout,
Int16GetDatum(i))));
}
}
return SM_SUCCESS;
}
/*
* smgrsync() -- Sync files to disk at checkpoint time.
*/
int
void
smgrsync(void)
{
int i;
@@ -549,26 +583,14 @@ smgrsync(void)
{
if (smgrsw[i].smgr_sync)
{
if ((*(smgrsw[i].smgr_sync)) () == SM_FAIL)
if (! (*(smgrsw[i].smgr_sync)) ())
elog(PANIC, "storage sync failed on %s: %m",
DatumGetCString(DirectFunctionCall1(smgrout,
Int16GetDatum(i))));
}
}
return SM_SUCCESS;
}
#ifdef NOT_USED
bool
smgriswo(int16 smgrno)
{
if (smgrno < 0 || smgrno >= NSmgr)
elog(ERROR, "invalid storage manager id: %d", smgrno);
return smgrwo[smgrno];
}
#endif
void
smgr_redo(XLogRecPtr lsn, XLogRecord *record)

19
src/backend/storage/smgr/smgrtype.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/smgr/smgrtype.c,v 1.22 2003/11/29 19:51:57 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/storage/smgr/smgrtype.c,v 1.23 2004/02/10 01:55:26 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -16,26 +16,21 @@
#include "storage/smgr.h"
typedef struct smgrid
{
char *smgr_name;
const char *smgr_name;
} smgrid;
/*
* StorageManager[] -- List of defined storage managers.
*
* The weird comma placement is to keep compilers happy no matter
* which of these is (or is not) defined.
*/
static smgrid StorageManager[] = {
{"magnetic disk"},
#ifdef STABLE_MEMORY_STORAGE
{"main memory"}
#endif
static const smgrid StorageManager[] = {
{"magnetic disk"}
};
static int NStorageManagers = lengthof(StorageManager);
static const int NStorageManagers = lengthof(StorageManager);
Datum
smgrin(PG_FUNCTION_ARGS)