diff options
Diffstat (limited to 'db2/mp/mp_bh.c')
| -rw-r--r-- | db2/mp/mp_bh.c | 176 |
1 files changed, 92 insertions, 84 deletions
diff --git a/db2/mp/mp_bh.c b/db2/mp/mp_bh.c index d89f9c2ded..12c53417d9 100644 --- a/db2/mp/mp_bh.c +++ b/db2/mp/mp_bh.c @@ -7,7 +7,7 @@ #include "config.h" #ifndef lint -static const char sccsid[] = "@(#)mp_bh.c 10.38 (Sleepycat) 5/20/98"; +static const char sccsid[] = "@(#)mp_bh.c 10.45 (Sleepycat) 11/25/98"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES @@ -42,11 +42,13 @@ __memp_bhwrite(dbmp, mfp, bhp, restartp, wrotep) { DB_MPOOLFILE *dbmfp; DB_MPREG *mpreg; + int incremented, ret; if (restartp != NULL) *restartp = 0; if (wrotep != NULL) *wrotep = 0; + incremented = 0; /* * Walk the process' DB_MPOOLFILE list and find a file descriptor for @@ -63,6 +65,13 @@ __memp_bhwrite(dbmp, mfp, bhp, restartp, wrotep) UNLOCKHANDLE(dbmp, dbmp->mutexp); return (0); } + + /* + * Increment the reference count -- see the comment in + * memp_fclose(). + */ + ++dbmfp->ref; + incremented = 1; break; } UNLOCKHANDLE(dbmp, dbmp->mutexp); @@ -117,7 +126,15 @@ __memp_bhwrite(dbmp, mfp, bhp, restartp, wrotep) 0, 0, mfp->stat.st_pagesize, 0, NULL, &dbmfp) != 0) return (0); -found: return (__memp_pgwrite(dbmfp, bhp, restartp, wrotep)); +found: ret = __memp_pgwrite(dbmfp, bhp, restartp, wrotep); + + if (incremented) { + LOCKHANDLE(dbmp, dbmp->mutexp); + --dbmfp->ref; + UNLOCKHANDLE(dbmp, dbmp->mutexp); + } + + return (ret); } /* @@ -132,11 +149,12 @@ __memp_pgread(dbmfp, bhp, can_create) BH *bhp; int can_create; { + DB_IO db_io; DB_MPOOL *dbmp; MPOOLFILE *mfp; - size_t pagesize; + size_t len, pagesize; ssize_t nr; - int ret; + int created, ret; dbmp = dbmfp->dbmp; mfp = dbmfp->mfp; @@ -147,70 +165,63 @@ __memp_pgread(dbmfp, bhp, can_create) UNLOCKREGION(dbmp); /* - * Temporary files may not yet have been created. - * - * Seek to the page location. + * Temporary files may not yet have been created. We don't create + * them now, we create them when the pages have to be flushed. */ - ret = 0; - LOCKHANDLE(dbmp, dbmfp->mutexp); - if (dbmfp->fd == -1 || (ret = - __db_seek(dbmfp->fd, pagesize, bhp->pgno, 0, 0, SEEK_SET)) != 0) { - if (!can_create) { - if (dbmfp->fd == -1) - ret = EINVAL; - UNLOCKHANDLE(dbmp, dbmfp->mutexp); + nr = 0; + if (dbmfp->fd == -1) + ret = 0; + else { + /* + * Ignore read errors if we have permission to create the page. + * Assume that the page doesn't exist, and that we'll create it + * when we write it out. + */ + db_io.fd_io = dbmfp->fd; + db_io.fd_lock = dbmp->reginfo.fd; + db_io.mutexp = + F_ISSET(dbmp, MP_LOCKHANDLE) ? dbmfp->mutexp : NULL; + db_io.pagesize = db_io.bytes = pagesize; + db_io.pgno = bhp->pgno; + db_io.buf = bhp->buf; + + ret = __os_io(&db_io, DB_IO_READ, &nr); + } + + created = 0; + if (nr < (ssize_t)pagesize) { + if (can_create) + created = 1; + else { + /* If we had a short read, ret may be 0. */ + if (ret == 0) + ret = EIO; __db_err(dbmp->dbenv, "%s: page %lu doesn't exist, create flag not set", __memp_fn(dbmfp), (u_long)bhp->pgno); goto err; } - UNLOCKHANDLE(dbmp, dbmfp->mutexp); - - /* Clear the created page. */ - if (mfp->clear_len == 0) - memset(bhp->buf, 0, pagesize); - else { - memset(bhp->buf, 0, mfp->clear_len); -#ifdef DIAGNOSTIC - memset(bhp->buf + mfp->clear_len, - 0xff, pagesize - mfp->clear_len); -#endif - } - - goto pgin; } /* - * Read the page; short reads are treated like creates, although - * any valid data is preserved. + * Clear any bytes we didn't read that need to be cleared. If we're + * running in diagnostic mode, smash any bytes on the page that are + * unknown quantities for the caller. */ - ret = __db_read(dbmfp->fd, bhp->buf, pagesize, &nr); - UNLOCKHANDLE(dbmp, dbmfp->mutexp); - if (ret != 0) - goto err; - - if (nr == (ssize_t)pagesize) - can_create = 0; - else { - if (!can_create) { - ret = EINVAL; - goto err; - } - - /* - * If we didn't fail until we tried the read, don't clear the - * whole page, it wouldn't be insane for a filesystem to just - * always behave that way. Else, clear any uninitialized data. - */ - if (nr == 0) - memset(bhp->buf, 0, - mfp->clear_len == 0 ? pagesize : mfp->clear_len); - else - memset(bhp->buf + nr, 0, pagesize - nr); + if (nr != (ssize_t)pagesize) { + len = mfp->clear_len == 0 ? pagesize : mfp->clear_len; + if (nr < (ssize_t)len) + memset(bhp->buf + nr, 0, len - nr); +#ifdef DIAGNOSTIC + if (nr > (ssize_t)len) + len = nr; + if (len < pagesize) + memset(bhp->buf + len, 0xdb, pagesize - len); +#endif } /* Call any pgin function. */ -pgin: ret = mfp->ftype == 0 ? 0 : __memp_pg(dbmfp, bhp, 1); + ret = mfp->ftype == 0 ? 0 : __memp_pg(dbmfp, bhp, 1); /* Unlock the buffer and reacquire the region lock. */ err: UNLOCKBUFFER(dbmp, bhp); @@ -225,7 +236,7 @@ err: UNLOCKBUFFER(dbmp, bhp); F_CLR(bhp, BH_TRASH); /* Update the statistics. */ - if (can_create) { + if (created) { ++dbmp->mp->stat.st_page_create; ++mfp->stat.st_page_create; } else { @@ -250,12 +261,12 @@ __memp_pgwrite(dbmfp, bhp, restartp, wrotep) int *restartp, *wrotep; { DB_ENV *dbenv; + DB_IO db_io; DB_LOG *lg_info; DB_LSN lsn; DB_MPOOL *dbmp; MPOOL *mp; MPOOLFILE *mfp; - size_t pagesize; ssize_t nw; int callpgin, ret, syncfail; const char *fail; @@ -270,7 +281,6 @@ __memp_pgwrite(dbmfp, bhp, restartp, wrotep) if (wrotep != NULL) *wrotep = 0; callpgin = 0; - pagesize = mfp->stat.st_pagesize; /* * Check the dirty bit -- this buffer may have been written since we @@ -326,34 +336,32 @@ __memp_pgwrite(dbmfp, bhp, restartp, wrotep) } /* Temporary files may not yet have been created. */ - LOCKHANDLE(dbmp, dbmfp->mutexp); - if (dbmfp->fd == -1 && - ((ret = __db_appname(dbenv, DB_APP_TMP, NULL, NULL, - DB_CREATE | DB_EXCL | DB_TEMPORARY, &dbmfp->fd, NULL)) != 0 || - dbmfp->fd == -1)) { + if (dbmfp->fd == -1) { + LOCKHANDLE(dbmp, dbmfp->mutexp); + if (dbmfp->fd == -1 && ((ret = __db_appname(dbenv, + DB_APP_TMP, NULL, NULL, DB_CREATE | DB_EXCL | DB_TEMPORARY, + &dbmfp->fd, NULL)) != 0 || dbmfp->fd == -1)) { + UNLOCKHANDLE(dbmp, dbmfp->mutexp); + __db_err(dbenv, + "unable to create temporary backing file"); + goto err; + } UNLOCKHANDLE(dbmp, dbmfp->mutexp); - __db_err(dbenv, "unable to create temporary backing file"); - goto err; } - /* - * Write the page out. - * - * XXX - * Shut the compiler up; it doesn't understand the correlation between - * the failing clauses to __db_lseek and __db_write and this ret != 0. - */ - COMPQUIET(fail, NULL); - if ((ret = - __db_seek(dbmfp->fd, pagesize, bhp->pgno, 0, 0, SEEK_SET)) != 0) - fail = "seek"; - else if ((ret = __db_write(dbmfp->fd, bhp->buf, pagesize, &nw)) != 0) + /* Write the page. */ + db_io.fd_io = dbmfp->fd; + db_io.fd_lock = dbmp->reginfo.fd; + db_io.mutexp = F_ISSET(dbmp, MP_LOCKHANDLE) ? dbmfp->mutexp : NULL; + db_io.pagesize = db_io.bytes = mfp->stat.st_pagesize; + db_io.pgno = bhp->pgno; + db_io.buf = bhp->buf; + if ((ret = __os_io(&db_io, DB_IO_WRITE, &nw)) != 0) { + __db_panic(dbenv, ret); fail = "write"; - UNLOCKHANDLE(dbmp, dbmfp->mutexp); - if (ret != 0) goto syserr; - - if (nw != (ssize_t)pagesize) { + } + if (nw != (ssize_t)mfp->stat.st_pagesize) { ret = EIO; fail = "write"; goto syserr; @@ -394,7 +402,7 @@ __memp_pgwrite(dbmfp, bhp, restartp, wrotep) if (F_ISSET(bhp, BH_WRITE)) { if (mfp->lsn_cnt == 1) { UNLOCKREGION(dbmp); - syncfail = __db_fsync(dbmfp->fd) != 0; + syncfail = __os_fsync(dbmfp->fd) != 0; LOCKREGION(dbmp); if (syncfail) F_SET(mp, MP_LSN_RETRY); @@ -574,11 +582,11 @@ __memp_upgrade(dbmp, dbmfp, mfp) ret = 1; } else { /* Swap the descriptors and set the upgrade flag. */ - (void)__db_close(dbmfp->fd); + (void)__os_close(dbmfp->fd); dbmfp->fd = fd; F_SET(dbmfp, MP_UPGRADE); ret = 0; } - FREES(rpath); + __os_freestr(rpath); return (ret); } |