diff options
author | Ulrich Drepper <drepper@redhat.com> | 1999-06-13 13:36:34 +0000 |
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committer | Ulrich Drepper <drepper@redhat.com> | 1999-06-13 13:36:34 +0000 |
commit | ec239360d13518a13f572b635d036c7d10028010 (patch) | |
tree | bdb5111363f45d2107849c2456b575d72779174c /db2/mp/mp_fopen.c | |
parent | fc3703521650a9b6db910a50c4fc0f410496e134 (diff) | |
download | glibc-ec239360d13518a13f572b635d036c7d10028010.tar.gz glibc-ec239360d13518a13f572b635d036c7d10028010.tar.xz glibc-ec239360d13518a13f572b635d036c7d10028010.zip |
Update.
* db2/Makefile (distribute): Remove files which do not exist anymore.
Diffstat (limited to 'db2/mp/mp_fopen.c')
-rw-r--r-- | db2/mp/mp_fopen.c | 123 |
1 files changed, 89 insertions, 34 deletions
diff --git a/db2/mp/mp_fopen.c b/db2/mp/mp_fopen.c index a4cbac8d4e..dd02662fd8 100644 --- a/db2/mp/mp_fopen.c +++ b/db2/mp/mp_fopen.c @@ -7,7 +7,7 @@ #include "config.h" #ifndef lint -static const char sccsid[] = "@(#)mp_fopen.c 10.47 (Sleepycat) 5/4/98"; +static const char sccsid[] = "@(#)mp_fopen.c 10.60 (Sleepycat) 1/1/99"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES @@ -43,6 +43,8 @@ memp_fopen(dbmp, path, flags, mode, pagesize, finfop, retp) { int ret; + MP_PANIC_CHECK(dbmp); + /* Validate arguments. */ if ((ret = __db_fchk(dbmp->dbenv, "memp_fopen", flags, DB_CREATE | DB_NOMMAP | DB_RDONLY)) != 0) @@ -53,6 +55,8 @@ memp_fopen(dbmp, path, flags, mode, pagesize, finfop, retp) __db_err(dbmp->dbenv, "memp_fopen: pagesize not specified"); return (EINVAL); } + if (finfop != NULL && finfop->clear_len > pagesize) + return (EINVAL); return (__memp_fopen(dbmp, NULL, path, flags, mode, pagesize, 1, finfop, retp)); @@ -80,7 +84,7 @@ __memp_fopen(dbmp, mfp, path, flags, mode, pagesize, needlock, finfop, retp) DB_MPOOLFILE *dbmfp; DB_MPOOL_FINFO finfo; db_pgno_t last_pgno; - size_t size; + size_t maxmap; u_int32_t mbytes, bytes; int ret; u_int8_t idbuf[DB_FILE_ID_LEN]; @@ -115,13 +119,11 @@ __memp_fopen(dbmp, mfp, path, flags, mode, pagesize, needlock, finfop, retp) } /* Allocate and initialize the per-process structure. */ - if ((dbmfp = - (DB_MPOOLFILE *)__db_calloc(1, sizeof(DB_MPOOLFILE))) == NULL) { - __db_err(dbenv, "memp_fopen: %s", strerror(ENOMEM)); - return (ENOMEM); - } + if ((ret = __os_calloc(1, sizeof(DB_MPOOLFILE), &dbmfp)) != 0) + return (ret); dbmfp->dbmp = dbmp; dbmfp->fd = -1; + dbmfp->ref = 1; if (LF_ISSET(DB_RDONLY)) F_SET(dbmfp, MP_READONLY); @@ -132,7 +134,6 @@ __memp_fopen(dbmp, mfp, path, flags, mode, pagesize, needlock, finfop, retp) ret = EINVAL; goto err; } - size = 0; last_pgno = 0; } else { /* Get the real name for this file and open it. */ @@ -146,21 +147,40 @@ __memp_fopen(dbmp, mfp, path, flags, mode, pagesize, needlock, finfop, retp) goto err; } - /* Don't permit files that aren't a multiple of the pagesize. */ - if ((ret = __db_ioinfo(rpath, + /* + * Don't permit files that aren't a multiple of the pagesize, + * and find the number of the last page in the file, all the + * time being careful not to overflow 32 bits. + * + * !!! + * We can't use off_t's here, or in any code in the mainline + * library for that matter. (We have to use them in the os + * stubs, of course, as there are system calls that take them + * as arguments.) The reason is that some customers build in + * environments where an off_t is 32-bits, but still run where + * offsets are 64-bits, and they pay us a lot of money. + */ + if ((ret = __os_ioinfo(rpath, dbmfp->fd, &mbytes, &bytes, NULL)) != 0) { __db_err(dbenv, "%s: %s", rpath, strerror(ret)); goto err; } - if (bytes % pagesize) { + + /* Page sizes have to be a power-of-two, ignore mbytes. */ + if (bytes % pagesize != 0) { __db_err(dbenv, "%s: file size not a multiple of the pagesize", rpath); ret = EINVAL; goto err; } - size = mbytes * MEGABYTE + bytes; - last_pgno = size == 0 ? 0 : (size - 1) / pagesize; + + last_pgno = mbytes * (MEGABYTE / pagesize); + last_pgno += bytes / pagesize; + + /* Correction: page numbers are zero-based, not 1-based. */ + if (last_pgno != 0) + --last_pgno; /* * Get the file id if we weren't given one. Generated file id's @@ -168,7 +188,7 @@ __memp_fopen(dbmp, mfp, path, flags, mode, pagesize, needlock, finfop, retp) * other process joining the party. */ if (finfop->fileid == NULL) { - if ((ret = __db_fileid(dbenv, rpath, 0, idbuf)) != 0) + if ((ret = __os_fileid(dbenv, rpath, 0, idbuf)) != 0) goto err; finfop->fileid = idbuf; } @@ -191,7 +211,7 @@ __memp_fopen(dbmp, mfp, path, flags, mode, pagesize, needlock, finfop, retp) } if (ret == 0 && F_ISSET(dbmp, MP_LOCKHANDLE) && (ret = - __memp_ralloc(dbmp, sizeof(db_mutex_t), NULL, &dbmfp->mutexp)) == 0) + __memp_alloc(dbmp, sizeof(db_mutex_t), NULL, &dbmfp->mutexp)) == 0) LOCKINIT(dbmp, dbmfp->mutexp); if (needlock) @@ -232,13 +252,15 @@ __memp_fopen(dbmp, mfp, path, flags, mode, pagesize, needlock, finfop, retp) F_CLR(mfp, MP_CAN_MMAP); if (LF_ISSET(DB_NOMMAP)) F_CLR(mfp, MP_CAN_MMAP); - if (size > (dbenv == NULL || dbenv->mp_mmapsize == 0 ? - DB_MAXMMAPSIZE : dbenv->mp_mmapsize)) + maxmap = dbenv == NULL || dbenv->mp_mmapsize == 0 ? + DB_MAXMMAPSIZE : dbenv->mp_mmapsize; + if (mbytes > maxmap / MEGABYTE || + (mbytes == maxmap / MEGABYTE && bytes >= maxmap % MEGABYTE)) F_CLR(mfp, MP_CAN_MMAP); } dbmfp->addr = NULL; if (F_ISSET(mfp, MP_CAN_MMAP)) { - dbmfp->len = size; + dbmfp->len = (size_t)mbytes * MEGABYTE + bytes; if (__db_mapfile(rpath, dbmfp->fd, dbmfp->len, 1, &dbmfp->addr) != 0) { dbmfp->addr = NULL; @@ -246,7 +268,7 @@ __memp_fopen(dbmp, mfp, path, flags, mode, pagesize, needlock, finfop, retp) } } if (rpath != NULL) - FREES(rpath); + __os_freestr(rpath); LOCKHANDLE(dbmp, dbmp->mutexp); TAILQ_INSERT_TAIL(&dbmp->dbmfq, dbmfp, q); @@ -260,11 +282,11 @@ err: /* * never get to here after we have successfully allocated it. */ if (rpath != NULL) - FREES(rpath); + __os_freestr(rpath); if (dbmfp->fd != -1) - (void)__db_close(dbmfp->fd); + (void)__os_close(dbmfp->fd); if (dbmfp != NULL) - FREE(dbmfp, sizeof(DB_MPOOLFILE)); + __os_free(dbmfp, sizeof(DB_MPOOLFILE)); return (ret); } @@ -315,7 +337,7 @@ __memp_mf_open(dbmp, path, pagesize, last_pgno, finfop, retp) } /* Allocate a new MPOOLFILE. */ - if ((ret = __memp_ralloc(dbmp, sizeof(MPOOLFILE), NULL, &mfp)) != 0) + if ((ret = __memp_alloc(dbmp, sizeof(MPOOLFILE), NULL, &mfp)) != 0) return (ret); *retp = mfp; @@ -334,21 +356,22 @@ __memp_mf_open(dbmp, path, pagesize, last_pgno, finfop, retp) mfp->stat.st_pagesize = pagesize; mfp->orig_last_pgno = mfp->last_pgno = last_pgno; - F_SET(mfp, MP_CAN_MMAP); if (ISTEMPORARY) F_SET(mfp, MP_TEMP); else { /* Copy the file path into shared memory. */ - if ((ret = __memp_ralloc(dbmp, + if ((ret = __memp_alloc(dbmp, strlen(path) + 1, &mfp->path_off, &p)) != 0) goto err; memcpy(p, path, strlen(path) + 1); /* Copy the file identification string into shared memory. */ - if ((ret = __memp_ralloc(dbmp, + if ((ret = __memp_alloc(dbmp, DB_FILE_ID_LEN, &mfp->fileid_off, &p)) != 0) goto err; memcpy(p, finfop->fileid, DB_FILE_ID_LEN); + + F_SET(mfp, MP_CAN_MMAP); } /* Copy the page cookie into shared memory. */ @@ -356,7 +379,7 @@ __memp_mf_open(dbmp, path, pagesize, last_pgno, finfop, retp) mfp->pgcookie_len = 0; mfp->pgcookie_off = 0; } else { - if ((ret = __memp_ralloc(dbmp, + if ((ret = __memp_alloc(dbmp, finfop->pgcookie->size, &mfp->pgcookie_off, &p)) != 0) goto err; memcpy(p, finfop->pgcookie->data, finfop->pgcookie->size); @@ -394,16 +417,48 @@ memp_fclose(dbmfp) dbmp = dbmfp->dbmp; ret = 0; + MP_PANIC_CHECK(dbmp); + + for (;;) { + LOCKHANDLE(dbmp, dbmp->mutexp); + + /* + * We have to reference count DB_MPOOLFILE structures as other + * threads may be using them. The problem only happens if the + * application makes a bad design choice. Here's the path: + * + * Thread A opens a database. + * Thread B uses thread A's DB_MPOOLFILE to write a buffer + * in order to free up memory in the mpool cache. + * Thread A closes the database while thread B is using the + * DB_MPOOLFILE structure. + * + * By opening all databases before creating the threads, and + * closing them after the threads have exited, applications + * get better performance and avoid the problem path entirely. + * + * Regardless, holding the DB_MPOOLFILE to flush a dirty buffer + * is a short-term lock, even in worst case, since we better be + * the only thread of control using the DB_MPOOLFILE structure + * to read pages *into* the cache. Wait until we're the only + * reference holder and remove the DB_MPOOLFILE structure from + * the list, so nobody else can even find it. + */ + if (dbmfp->ref == 1) { + TAILQ_REMOVE(&dbmp->dbmfq, dbmfp, q); + break; + } + UNLOCKHANDLE(dbmp, dbmp->mutexp); + + (void)__os_sleep(1, 0); + } + UNLOCKHANDLE(dbmp, dbmp->mutexp); + /* Complain if pinned blocks never returned. */ if (dbmfp->pinref != 0) __db_err(dbmp->dbenv, "%s: close: %lu blocks left pinned", __memp_fn(dbmfp), (u_long)dbmfp->pinref); - /* Remove the DB_MPOOLFILE structure from the list. */ - LOCKHANDLE(dbmp, dbmp->mutexp); - TAILQ_REMOVE(&dbmp->dbmfq, dbmfp, q); - UNLOCKHANDLE(dbmp, dbmp->mutexp); - /* Close the underlying MPOOLFILE. */ (void)__memp_mf_close(dbmp, dbmfp); @@ -414,7 +469,7 @@ memp_fclose(dbmfp) "%s: %s", __memp_fn(dbmfp), strerror(ret)); /* Close the file; temporary files may not yet have been created. */ - if (dbmfp->fd != -1 && (t_ret = __db_close(dbmfp->fd)) != 0) { + if (dbmfp->fd != -1 && (t_ret = __os_close(dbmfp->fd)) != 0) { __db_err(dbmp->dbenv, "%s: %s", __memp_fn(dbmfp), strerror(t_ret)); if (ret != 0) @@ -429,7 +484,7 @@ memp_fclose(dbmfp) } /* Discard the DB_MPOOLFILE structure. */ - FREE(dbmfp, sizeof(DB_MPOOLFILE)); + __os_free(dbmfp, sizeof(DB_MPOOLFILE)); return (ret); } |