From c24dcd0cfd949bdf245814c4c2b3df828ee7db36 Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Wed, 7 Nov 2018 09:51:50 +1300 Subject: [PATCH] Use pg_pread() and pg_pwrite() for data files and WAL. Cut down on system calls by doing random I/O using offset-based OS routines where available. Remove the code for tracking the 'virtual' seek position. The only reason left to call FileSeek() was to get the file's size, so provide a new function FileSize() instead. Author: Oskari Saarenmaa, Thomas Munro Reviewed-by: Thomas Munro, Jesper Pedersen, Tom Lane, Alvaro Herrera Discussion: https://postgr.es/m/CAEepm=02rapCpPR3ZGF2vW=SBHSdFYO_bz_f-wwWJonmA3APgw@mail.gmail.com Discussion: https://postgr.es/m/b8748d39-0b19-0514-a1b9-4e5a28e6a208%40gmail.com Discussion: https://postgr.es/m/a86bd200-ebbe-d829-e3ca-0c4474b2fcb7%40ohmu.fi --- src/backend/access/heap/rewriteheap.c | 2 +- src/backend/access/transam/xlog.c | 30 +--- src/backend/storage/file/buffile.c | 46 +----- src/backend/storage/file/fd.c | 205 ++++---------------------- src/backend/storage/smgr/md.c | 35 +---- src/include/storage/fd.h | 12 +- 6 files changed, 42 insertions(+), 288 deletions(-) diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c index 7127788964..c5db75afa1 100644 --- a/src/backend/access/heap/rewriteheap.c +++ b/src/backend/access/heap/rewriteheap.c @@ -935,7 +935,7 @@ logical_heap_rewrite_flush_mappings(RewriteState state) * Note that we deviate from the usual WAL coding practices here, * check the above "Logical rewrite support" comment for reasoning. */ - written = FileWrite(src->vfd, waldata_start, len, + written = FileWrite(src->vfd, waldata_start, len, src->off, WAIT_EVENT_LOGICAL_REWRITE_WRITE); if (written != len) ereport(ERROR, diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 246869bba2..7eed5866d2 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -2478,18 +2478,6 @@ XLogWrite(XLogwrtRqst WriteRqst, bool flexible) Size nleft; int written; - /* Need to seek in the file? */ - if (openLogOff != startoffset) - { - if (lseek(openLogFile, (off_t) startoffset, SEEK_SET) < 0) - ereport(PANIC, - (errcode_for_file_access(), - errmsg("could not seek in log file %s to offset %u: %m", - XLogFileNameP(ThisTimeLineID, openLogSegNo), - startoffset))); - openLogOff = startoffset; - } - /* OK to write the page(s) */ from = XLogCtl->pages + startidx * (Size) XLOG_BLCKSZ; nbytes = npages * (Size) XLOG_BLCKSZ; @@ -2498,7 +2486,7 @@ XLogWrite(XLogwrtRqst WriteRqst, bool flexible) { errno = 0; pgstat_report_wait_start(WAIT_EVENT_WAL_WRITE); - written = write(openLogFile, from, nleft); + written = pg_pwrite(openLogFile, from, nleft, startoffset); pgstat_report_wait_end(); if (written <= 0) { @@ -2513,6 +2501,7 @@ XLogWrite(XLogwrtRqst WriteRqst, bool flexible) } nleft -= written; from += written; + startoffset += written; } while (nleft > 0); /* Update state for write */ @@ -11821,22 +11810,9 @@ retry: /* Read the requested page */ readOff = targetPageOff; - if (lseek(readFile, (off_t) readOff, SEEK_SET) < 0) - { - char fname[MAXFNAMELEN]; - int save_errno = errno; - - XLogFileName(fname, curFileTLI, readSegNo, wal_segment_size); - errno = save_errno; - ereport(emode_for_corrupt_record(emode, targetPagePtr + reqLen), - (errcode_for_file_access(), - errmsg("could not seek in log segment %s to offset %u: %m", - fname, readOff))); - goto next_record_is_invalid; - } pgstat_report_wait_start(WAIT_EVENT_WAL_READ); - r = read(readFile, readBuf, XLOG_BLCKSZ); + r = pg_pread(readFile, readBuf, XLOG_BLCKSZ, (off_t) readOff); if (r != XLOG_BLCKSZ) { char fname[MAXFNAMELEN]; diff --git a/src/backend/storage/file/buffile.c b/src/backend/storage/file/buffile.c index e93813d973..dd687dfe71 100644 --- a/src/backend/storage/file/buffile.c +++ b/src/backend/storage/file/buffile.c @@ -67,12 +67,6 @@ struct BufFile int numFiles; /* number of physical files in set */ /* all files except the last have length exactly MAX_PHYSICAL_FILESIZE */ File *files; /* palloc'd array with numFiles entries */ - off_t *offsets; /* palloc'd array with numFiles entries */ - - /* - * offsets[i] is the current seek position of files[i]. We use this to - * avoid making redundant FileSeek calls. - */ bool isInterXact; /* keep open over transactions? */ bool dirty; /* does buffer need to be written? */ @@ -116,7 +110,6 @@ makeBufFileCommon(int nfiles) BufFile *file = (BufFile *) palloc(sizeof(BufFile)); file->numFiles = nfiles; - file->offsets = (off_t *) palloc0(sizeof(off_t) * nfiles); file->isInterXact = false; file->dirty = false; file->resowner = CurrentResourceOwner; @@ -170,10 +163,7 @@ extendBufFile(BufFile *file) file->files = (File *) repalloc(file->files, (file->numFiles + 1) * sizeof(File)); - file->offsets = (off_t *) repalloc(file->offsets, - (file->numFiles + 1) * sizeof(off_t)); file->files[file->numFiles] = pfile; - file->offsets[file->numFiles] = 0L; file->numFiles++; } @@ -396,7 +386,6 @@ BufFileClose(BufFile *file) FileClose(file->files[i]); /* release the buffer space */ pfree(file->files); - pfree(file->offsets); pfree(file); } @@ -422,27 +411,17 @@ BufFileLoadBuffer(BufFile *file) file->curOffset = 0L; } - /* - * May need to reposition physical file. - */ - thisfile = file->files[file->curFile]; - if (file->curOffset != file->offsets[file->curFile]) - { - if (FileSeek(thisfile, file->curOffset, SEEK_SET) != file->curOffset) - return; /* seek failed, read nothing */ - file->offsets[file->curFile] = file->curOffset; - } - /* * Read whatever we can get, up to a full bufferload. */ + thisfile = file->files[file->curFile]; file->nbytes = FileRead(thisfile, file->buffer.data, sizeof(file->buffer), + file->curOffset, WAIT_EVENT_BUFFILE_READ); if (file->nbytes < 0) file->nbytes = 0; - file->offsets[file->curFile] += file->nbytes; /* we choose not to advance curOffset here */ if (file->nbytes > 0) @@ -491,23 +470,14 @@ BufFileDumpBuffer(BufFile *file) if ((off_t) bytestowrite > availbytes) bytestowrite = (int) availbytes; - /* - * May need to reposition physical file. - */ thisfile = file->files[file->curFile]; - if (file->curOffset != file->offsets[file->curFile]) - { - if (FileSeek(thisfile, file->curOffset, SEEK_SET) != file->curOffset) - return; /* seek failed, give up */ - file->offsets[file->curFile] = file->curOffset; - } bytestowrite = FileWrite(thisfile, file->buffer.data + wpos, bytestowrite, + file->curOffset, WAIT_EVENT_BUFFILE_WRITE); if (bytestowrite <= 0) return; /* failed to write */ - file->offsets[file->curFile] += bytestowrite; file->curOffset += bytestowrite; wpos += bytestowrite; @@ -803,11 +773,10 @@ BufFileSize(BufFile *file) { off_t lastFileSize; - /* Get the size of the last physical file by seeking to end. */ - lastFileSize = FileSeek(file->files[file->numFiles - 1], 0, SEEK_END); + /* Get the size of the last physical file. */ + lastFileSize = FileSize(file->files[file->numFiles - 1]); if (lastFileSize < 0) return -1; - file->offsets[file->numFiles - 1] = lastFileSize; return ((file->numFiles - 1) * (off_t) MAX_PHYSICAL_FILESIZE) + lastFileSize; @@ -849,13 +818,8 @@ BufFileAppend(BufFile *target, BufFile *source) target->files = (File *) repalloc(target->files, sizeof(File) * newNumFiles); - target->offsets = (off_t *) - repalloc(target->offsets, sizeof(off_t) * newNumFiles); for (i = target->numFiles; i < newNumFiles; i++) - { target->files[i] = source->files[i - target->numFiles]; - target->offsets[i] = source->offsets[i - target->numFiles]; - } target->numFiles = newNumFiles; return startBlock; diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c index 8dd51f1767..6611edbbd2 100644 --- a/src/backend/storage/file/fd.c +++ b/src/backend/storage/file/fd.c @@ -16,8 +16,8 @@ * including base tables, scratch files (e.g., sort and hash spool * files), and random calls to C library routines like system(3); it * is quite easy to exceed system limits on the number of open files a - * single process can have. (This is around 256 on many modern - * operating systems, but can be as low as 32 on others.) + * single process can have. (This is around 1024 on many modern + * operating systems, but may be lower on others.) * * VFDs are managed as an LRU pool, with actual OS file descriptors * being opened and closed as needed. Obviously, if a routine is @@ -167,15 +167,6 @@ int max_safe_fds = 32; /* default if not changed */ #define FileIsNotOpen(file) (VfdCache[file].fd == VFD_CLOSED) -/* - * Note: a VFD's seekPos is normally always valid, but if for some reason - * an lseek() fails, it might become set to FileUnknownPos. We can struggle - * along without knowing the seek position in many cases, but in some places - * we have to fail if we don't have it. - */ -#define FileUnknownPos ((off_t) -1) -#define FilePosIsUnknown(pos) ((pos) < 0) - /* these are the assigned bits in fdstate below: */ #define FD_DELETE_AT_CLOSE (1 << 0) /* T = delete when closed */ #define FD_CLOSE_AT_EOXACT (1 << 1) /* T = close at eoXact */ @@ -189,7 +180,6 @@ typedef struct vfd File nextFree; /* link to next free VFD, if in freelist */ File lruMoreRecently; /* doubly linked recency-of-use list */ File lruLessRecently; - off_t seekPos; /* current logical file position, or -1 */ off_t fileSize; /* current size of file (0 if not temporary) */ char *fileName; /* name of file, or NULL for unused VFD */ /* NB: fileName is malloc'd, and must be free'd when closing the VFD */ @@ -407,9 +397,7 @@ pg_fdatasync(int fd) /* * pg_flush_data --- advise OS that the described dirty data should be flushed * - * offset of 0 with nbytes 0 means that the entire file should be flushed; - * in this case, this function may have side-effects on the file's - * seek position! + * offset of 0 with nbytes 0 means that the entire file should be flushed */ void pg_flush_data(int fd, off_t offset, off_t nbytes) @@ -1029,22 +1017,6 @@ LruDelete(File file) vfdP = &VfdCache[file]; - /* - * Normally we should know the seek position, but if for some reason we - * have lost track of it, try again to get it. If we still can't get it, - * we have a problem: we will be unable to restore the file seek position - * when and if the file is re-opened. But we can't really throw an error - * and refuse to close the file, or activities such as transaction cleanup - * will be broken. - */ - if (FilePosIsUnknown(vfdP->seekPos)) - { - vfdP->seekPos = lseek(vfdP->fd, (off_t) 0, SEEK_CUR); - if (FilePosIsUnknown(vfdP->seekPos)) - elog(LOG, "could not seek file \"%s\" before closing: %m", - vfdP->fileName); - } - /* * Close the file. We aren't expecting this to fail; if it does, better * to leak the FD than to mess up our internal state. @@ -1113,33 +1085,6 @@ LruInsert(File file) { ++nfile; } - - /* - * Seek to the right position. We need no special case for seekPos - * equal to FileUnknownPos, as lseek() will certainly reject that - * (thus completing the logic noted in LruDelete() that we will fail - * to re-open a file if we couldn't get its seek position before - * closing). - */ - if (vfdP->seekPos != (off_t) 0) - { - if (lseek(vfdP->fd, vfdP->seekPos, SEEK_SET) < 0) - { - /* - * If we fail to restore the seek position, treat it like an - * open() failure. - */ - int save_errno = errno; - - elog(LOG, "could not seek file \"%s\" after re-opening: %m", - vfdP->fileName); - (void) close(vfdP->fd); - vfdP->fd = VFD_CLOSED; - --nfile; - errno = save_errno; - return -1; - } - } } /* @@ -1406,7 +1351,6 @@ PathNameOpenFilePerm(const char *fileName, int fileFlags, mode_t fileMode) /* Saved flags are adjusted to be OK for re-opening file */ vfdP->fileFlags = fileFlags & ~(O_CREAT | O_TRUNC | O_EXCL); vfdP->fileMode = fileMode; - vfdP->seekPos = 0; vfdP->fileSize = 0; vfdP->fdstate = 0x0; vfdP->resowner = NULL; @@ -1820,7 +1764,6 @@ FileClose(File file) /* * FilePrefetch - initiate asynchronous read of a given range of the file. - * The logical seek position is unaffected. * * Currently the only implementation of this function is using posix_fadvise * which is the simplest standardized interface that accomplishes this. @@ -1867,10 +1810,6 @@ FileWriteback(File file, off_t offset, off_t nbytes, uint32 wait_event_info) file, VfdCache[file].fileName, (int64) offset, (int64) nbytes)); - /* - * Caution: do not call pg_flush_data with nbytes = 0, it could trash the - * file's seek position. We prefer to define that as a no-op here. - */ if (nbytes <= 0) return; @@ -1884,7 +1823,8 @@ FileWriteback(File file, off_t offset, off_t nbytes, uint32 wait_event_info) } int -FileRead(File file, char *buffer, int amount, uint32 wait_event_info) +FileRead(File file, char *buffer, int amount, off_t offset, + uint32 wait_event_info) { int returnCode; Vfd *vfdP; @@ -1893,7 +1833,7 @@ FileRead(File file, char *buffer, int amount, uint32 wait_event_info) DO_DB(elog(LOG, "FileRead: %d (%s) " INT64_FORMAT " %d %p", file, VfdCache[file].fileName, - (int64) VfdCache[file].seekPos, + (int64) offset, amount, buffer)); returnCode = FileAccess(file); @@ -1904,16 +1844,10 @@ FileRead(File file, char *buffer, int amount, uint32 wait_event_info) retry: pgstat_report_wait_start(wait_event_info); - returnCode = read(vfdP->fd, buffer, amount); + returnCode = pg_pread(vfdP->fd, buffer, amount, offset); pgstat_report_wait_end(); - if (returnCode >= 0) - { - /* if seekPos is unknown, leave it that way */ - if (!FilePosIsUnknown(vfdP->seekPos)) - vfdP->seekPos += returnCode; - } - else + if (returnCode < 0) { /* * Windows may run out of kernel buffers and return "Insufficient @@ -1939,16 +1873,14 @@ retry: /* OK to retry if interrupted */ if (errno == EINTR) goto retry; - - /* Trouble, so assume we don't know the file position anymore */ - vfdP->seekPos = FileUnknownPos; } return returnCode; } int -FileWrite(File file, char *buffer, int amount, uint32 wait_event_info) +FileWrite(File file, char *buffer, int amount, off_t offset, + uint32 wait_event_info) { int returnCode; Vfd *vfdP; @@ -1957,7 +1889,7 @@ FileWrite(File file, char *buffer, int amount, uint32 wait_event_info) DO_DB(elog(LOG, "FileWrite: %d (%s) " INT64_FORMAT " %d %p", file, VfdCache[file].fileName, - (int64) VfdCache[file].seekPos, + (int64) offset, amount, buffer)); returnCode = FileAccess(file); @@ -1976,26 +1908,13 @@ FileWrite(File file, char *buffer, int amount, uint32 wait_event_info) */ if (temp_file_limit >= 0 && (vfdP->fdstate & FD_TEMP_FILE_LIMIT)) { - off_t newPos; + off_t past_write = offset + amount; - /* - * Normally we should know the seek position, but if for some reason - * we have lost track of it, try again to get it. Here, it's fine to - * throw an error if we still can't get it. - */ - if (FilePosIsUnknown(vfdP->seekPos)) - { - vfdP->seekPos = lseek(vfdP->fd, (off_t) 0, SEEK_CUR); - if (FilePosIsUnknown(vfdP->seekPos)) - elog(ERROR, "could not seek file \"%s\": %m", vfdP->fileName); - } - - newPos = vfdP->seekPos + amount; - if (newPos > vfdP->fileSize) + if (past_write > vfdP->fileSize) { uint64 newTotal = temporary_files_size; - newTotal += newPos - vfdP->fileSize; + newTotal += past_write - vfdP->fileSize; if (newTotal > (uint64) temp_file_limit * (uint64) 1024) ereport(ERROR, (errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED), @@ -2007,7 +1926,7 @@ FileWrite(File file, char *buffer, int amount, uint32 wait_event_info) retry: errno = 0; pgstat_report_wait_start(wait_event_info); - returnCode = write(vfdP->fd, buffer, amount); + returnCode = pg_pwrite(VfdCache[file].fd, buffer, amount, offset); pgstat_report_wait_end(); /* if write didn't set errno, assume problem is no disk space */ @@ -2016,10 +1935,6 @@ retry: if (returnCode >= 0) { - /* if seekPos is unknown, leave it that way */ - if (!FilePosIsUnknown(vfdP->seekPos)) - vfdP->seekPos += returnCode; - /* * Maintain fileSize and temporary_files_size if it's a temp file. * @@ -2029,12 +1944,12 @@ retry: */ if (vfdP->fdstate & FD_TEMP_FILE_LIMIT) { - off_t newPos = vfdP->seekPos; + off_t past_write = offset + amount; - if (newPos > vfdP->fileSize) + if (past_write > vfdP->fileSize) { - temporary_files_size += newPos - vfdP->fileSize; - vfdP->fileSize = newPos; + temporary_files_size += past_write - vfdP->fileSize; + vfdP->fileSize = past_write; } } } @@ -2060,9 +1975,6 @@ retry: /* OK to retry if interrupted */ if (errno == EINTR) goto retry; - - /* Trouble, so assume we don't know the file position anymore */ - vfdP->seekPos = FileUnknownPos; } return returnCode; @@ -2090,93 +2002,26 @@ FileSync(File file, uint32 wait_event_info) } off_t -FileSeek(File file, off_t offset, int whence) +FileSize(File file) { Vfd *vfdP; Assert(FileIsValid(file)); - DO_DB(elog(LOG, "FileSeek: %d (%s) " INT64_FORMAT " " INT64_FORMAT " %d", - file, VfdCache[file].fileName, - (int64) VfdCache[file].seekPos, - (int64) offset, whence)); + DO_DB(elog(LOG, "FileSize %d (%s)", + file, VfdCache[file].fileName)); vfdP = &VfdCache[file]; if (FileIsNotOpen(file)) { - switch (whence) - { - case SEEK_SET: - if (offset < 0) - { - errno = EINVAL; - return (off_t) -1; - } - vfdP->seekPos = offset; - break; - case SEEK_CUR: - if (FilePosIsUnknown(vfdP->seekPos) || - vfdP->seekPos + offset < 0) - { - errno = EINVAL; - return (off_t) -1; - } - vfdP->seekPos += offset; - break; - case SEEK_END: - if (FileAccess(file) < 0) - return (off_t) -1; - vfdP->seekPos = lseek(vfdP->fd, offset, whence); - break; - default: - elog(ERROR, "invalid whence: %d", whence); - break; - } - } - else - { - switch (whence) - { - case SEEK_SET: - if (offset < 0) - { - errno = EINVAL; - return (off_t) -1; - } - if (vfdP->seekPos != offset) - vfdP->seekPos = lseek(vfdP->fd, offset, whence); - break; - case SEEK_CUR: - if (offset != 0 || FilePosIsUnknown(vfdP->seekPos)) - vfdP->seekPos = lseek(vfdP->fd, offset, whence); - break; - case SEEK_END: - vfdP->seekPos = lseek(vfdP->fd, offset, whence); - break; - default: - elog(ERROR, "invalid whence: %d", whence); - break; - } + if (FileAccess(file) < 0) + return (off_t) -1; } - return vfdP->seekPos; + return lseek(VfdCache[file].fd, 0, SEEK_END); } -/* - * XXX not actually used but here for completeness - */ -#ifdef NOT_USED -off_t -FileTell(File file) -{ - Assert(FileIsValid(file)); - DO_DB(elog(LOG, "FileTell %d (%s)", - file, VfdCache[file].fileName)); - return VfdCache[file].seekPos; -} -#endif - int FileTruncate(File file, off_t offset, uint32 wait_event_info) { diff --git a/src/backend/storage/smgr/md.c b/src/backend/storage/smgr/md.c index f4374d077b..86013a5c8b 100644 --- a/src/backend/storage/smgr/md.c +++ b/src/backend/storage/smgr/md.c @@ -522,22 +522,7 @@ mdextend(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum, Assert(seekpos < (off_t) BLCKSZ * RELSEG_SIZE); - /* - * Note: because caller usually obtained blocknum by calling mdnblocks, - * which did a seek(SEEK_END), this seek is often redundant and will be - * optimized away by fd.c. It's not redundant, however, if there is a - * partial page at the end of the file. In that case we want to try to - * overwrite the partial page with a full page. It's also not redundant - * if bufmgr.c had to dump another buffer of the same file to make room - * for the new page's buffer. - */ - if (FileSeek(v->mdfd_vfd, seekpos, SEEK_SET) != seekpos) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not seek to block %u in file \"%s\": %m", - blocknum, FilePathName(v->mdfd_vfd)))); - - if ((nbytes = FileWrite(v->mdfd_vfd, buffer, BLCKSZ, WAIT_EVENT_DATA_FILE_EXTEND)) != BLCKSZ) + if ((nbytes = FileWrite(v->mdfd_vfd, buffer, BLCKSZ, seekpos, WAIT_EVENT_DATA_FILE_EXTEND)) != BLCKSZ) { if (nbytes < 0) ereport(ERROR, @@ -748,13 +733,7 @@ mdread(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum, Assert(seekpos < (off_t) BLCKSZ * RELSEG_SIZE); - if (FileSeek(v->mdfd_vfd, seekpos, SEEK_SET) != seekpos) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not seek to block %u in file \"%s\": %m", - blocknum, FilePathName(v->mdfd_vfd)))); - - nbytes = FileRead(v->mdfd_vfd, buffer, BLCKSZ, WAIT_EVENT_DATA_FILE_READ); + nbytes = FileRead(v->mdfd_vfd, buffer, BLCKSZ, seekpos, WAIT_EVENT_DATA_FILE_READ); TRACE_POSTGRESQL_SMGR_MD_READ_DONE(forknum, blocknum, reln->smgr_rnode.node.spcNode, @@ -824,13 +803,7 @@ mdwrite(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum, Assert(seekpos < (off_t) BLCKSZ * RELSEG_SIZE); - if (FileSeek(v->mdfd_vfd, seekpos, SEEK_SET) != seekpos) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not seek to block %u in file \"%s\": %m", - blocknum, FilePathName(v->mdfd_vfd)))); - - nbytes = FileWrite(v->mdfd_vfd, buffer, BLCKSZ, WAIT_EVENT_DATA_FILE_WRITE); + nbytes = FileWrite(v->mdfd_vfd, buffer, BLCKSZ, seekpos, WAIT_EVENT_DATA_FILE_WRITE); TRACE_POSTGRESQL_SMGR_MD_WRITE_DONE(forknum, blocknum, reln->smgr_rnode.node.spcNode, @@ -1979,7 +1952,7 @@ _mdnblocks(SMgrRelation reln, ForkNumber forknum, MdfdVec *seg) { off_t len; - len = FileSeek(seg->mdfd_vfd, 0L, SEEK_END); + len = FileSize(seg->mdfd_vfd); if (len < 0) ereport(ERROR, (errcode_for_file_access(), diff --git a/src/include/storage/fd.h b/src/include/storage/fd.h index 8e7c9728f4..1289589a46 100644 --- a/src/include/storage/fd.h +++ b/src/include/storage/fd.h @@ -15,7 +15,7 @@ /* * calls: * - * File {Close, Read, Write, Seek, Tell, Sync} + * File {Close, Read, Write, Size, Sync} * {Path Name Open, Allocate, Free} File * * These are NOT JUST RENAMINGS OF THE UNIX ROUTINES. @@ -42,10 +42,6 @@ #include -/* - * FileSeek uses the standard UNIX lseek(2) flags. - */ - typedef int File; @@ -68,10 +64,10 @@ extern File PathNameOpenFilePerm(const char *fileName, int fileFlags, mode_t fil extern File OpenTemporaryFile(bool interXact); extern void FileClose(File file); extern int FilePrefetch(File file, off_t offset, int amount, uint32 wait_event_info); -extern int FileRead(File file, char *buffer, int amount, uint32 wait_event_info); -extern int FileWrite(File file, char *buffer, int amount, uint32 wait_event_info); +extern int FileRead(File file, char *buffer, int amount, off_t offset, uint32 wait_event_info); +extern int FileWrite(File file, char *buffer, int amount, off_t offset, uint32 wait_event_info); extern int FileSync(File file, uint32 wait_event_info); -extern off_t FileSeek(File file, off_t offset, int whence); +extern off_t FileSize(File file); extern int FileTruncate(File file, off_t offset, uint32 wait_event_info); extern void FileWriteback(File file, off_t offset, off_t nbytes, uint32 wait_event_info); extern char *FilePathName(File file);