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| author | Marc Horowitz <marc@mit.edu> | 1996-07-22 20:49:46 +0000 |
|---|---|---|
| committer | Marc Horowitz <marc@mit.edu> | 1996-07-22 20:49:46 +0000 |
| commit | edf8b4d8a6a665c2aa150993cd813ea6c5cf12e1 (patch) | |
| tree | 6c2974a97b448c040fa4a31708ec5e02f187526c /src/util/db2/mpool/mpool.c | |
| parent | 013bb1391582ed9e653ae706e398ddb8d08cfcc9 (diff) | |
| download | krb5-edf8b4d8a6a665c2aa150993cd813ea6c5cf12e1.tar.gz krb5-edf8b4d8a6a665c2aa150993cd813ea6c5cf12e1.tar.xz krb5-edf8b4d8a6a665c2aa150993cd813ea6c5cf12e1.zip | |
this commit includes all the changes on the OV_9510_INTEGRATION and
OV_MERGE branches. This includes, but is not limited to, the new openvision
admin system, and major changes to gssapi to add functionality, and bring
the implementation in line with rfc1964. before committing, the
code was built and tested for netbsd and solaris.
git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@8774 dc483132-0cff-0310-8789-dd5450dbe970
Diffstat (limited to 'src/util/db2/mpool/mpool.c')
| -rw-r--r-- | src/util/db2/mpool/mpool.c | 502 |
1 files changed, 502 insertions, 0 deletions
diff --git a/src/util/db2/mpool/mpool.c b/src/util/db2/mpool/mpool.c new file mode 100644 index 000000000..12e557d03 --- /dev/null +++ b/src/util/db2/mpool/mpool.c @@ -0,0 +1,502 @@ +/*- + * Copyright (c) 1990, 1993, 1994 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)mpool.c 8.7 (Berkeley) 11/2/95"; +#endif /* LIBC_SCCS and not lint */ + +#include <sys/param.h> +#include <sys/stat.h> + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "db-int.h" +#include "mpool.h" + +static BKT *mpool_bkt __P((MPOOL *)); +static BKT *mpool_look __P((MPOOL *, db_pgno_t)); +static int mpool_write __P((MPOOL *, BKT *)); + +/* + * mpool_open -- + * Initialize a memory pool. + */ +MPOOL * +mpool_open(key, fd, pagesize, maxcache) + void *key; + int fd; + db_pgno_t pagesize, maxcache; +{ + struct stat sb; + MPOOL *mp; + int entry; + + /* + * Get information about the file. + * + * XXX + * We don't currently handle pipes, although we should. + */ + if (fstat(fd, &sb)) + return (NULL); + if (!S_ISREG(sb.st_mode)) { + errno = ESPIPE; + return (NULL); + } + + /* Allocate and initialize the MPOOL cookie. */ + if ((mp = (MPOOL *)calloc(1, sizeof(MPOOL))) == NULL) + return (NULL); + CIRCLEQ_INIT(&mp->lqh); + for (entry = 0; entry < HASHSIZE; ++entry) + CIRCLEQ_INIT(&mp->hqh[entry]); + mp->maxcache = maxcache; + mp->npages = sb.st_size / pagesize; + mp->pagesize = pagesize; + mp->fd = fd; + return (mp); +} + +/* + * mpool_filter -- + * Initialize input/output filters. + */ +void +mpool_filter(mp, pgin, pgout, pgcookie) + MPOOL *mp; + void (*pgin) __P((void *, db_pgno_t, void *)); + void (*pgout) __P((void *, db_pgno_t, void *)); + void *pgcookie; +{ + mp->pgin = pgin; + mp->pgout = pgout; + mp->pgcookie = pgcookie; +} + +/* + * mpool_new -- + * Get a new page of memory. + */ +void * +mpool_new(mp, pgnoaddr, flags) + MPOOL *mp; + db_pgno_t *pgnoaddr; + u_int flags; +{ + struct _hqh *head; + BKT *bp; + + if (mp->npages == MAX_PAGE_NUMBER) { + (void)fprintf(stderr, "mpool_new: page allocation overflow.\n"); + abort(); + } +#ifdef STATISTICS + ++mp->pagenew; +#endif + /* + * Get a BKT from the cache. Assign a new page number, attach + * it to the head of the hash chain, the tail of the lru chain, + * and return. + */ + if ((bp = mpool_bkt(mp)) == NULL) + return (NULL); + if (flags == MPOOL_PAGE_REQUEST) { + mp->npages++; + bp->pgno = *pgnoaddr; + } else + bp->pgno = *pgnoaddr = mp->npages++; + + bp->flags = MPOOL_PINNED | MPOOL_INUSE; + + head = &mp->hqh[HASHKEY(bp->pgno)]; + CIRCLEQ_INSERT_HEAD(head, bp, hq); + CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q); + return (bp->page); +} + +int +mpool_delete(mp, page) + MPOOL *mp; + void *page; +{ + struct _hqh *head; + BKT *bp; + + bp = (BKT *)((char *)page - sizeof(BKT)); + +#ifdef DEBUG + if (!(bp->flags & MPOOL_PINNED)) { + (void)fprintf(stderr, + "mpool_delete: page %d not pinned\n", bp->pgno); + abort(); + } +#endif + + /* Remove from the hash and lru queues. */ + head = &mp->hqh[HASHKEY(bp->pgno)]; + CIRCLEQ_REMOVE(head, bp, hq); + CIRCLEQ_REMOVE(&mp->lqh, bp, q); + + free(bp); + return (RET_SUCCESS); +} + +/* + * mpool_get + * Get a page. + */ +void * +mpool_get(mp, pgno, flags) + MPOOL *mp; + db_pgno_t pgno; + u_int flags; /* XXX not used? */ +{ + struct _hqh *head; + BKT *bp; + off_t off; + int nr; + +#ifdef STATISTICS + ++mp->pageget; +#endif + + /* Check for a page that is cached. */ + if ((bp = mpool_look(mp, pgno)) != NULL) { +#ifdef DEBUG + if (!(flags & MPOOL_IGNOREPIN) && bp->flags & MPOOL_PINNED) { + (void)fprintf(stderr, + "mpool_get: page %d already pinned\n", bp->pgno); + abort(); + } +#endif + /* + * Move the page to the head of the hash chain and the tail + * of the lru chain. + */ + head = &mp->hqh[HASHKEY(bp->pgno)]; + CIRCLEQ_REMOVE(head, bp, hq); + CIRCLEQ_INSERT_HEAD(head, bp, hq); + CIRCLEQ_REMOVE(&mp->lqh, bp, q); + CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q); + + /* Return a pinned page. */ + bp->flags |= MPOOL_PINNED; + return (bp->page); + } + + /* Get a page from the cache. */ + if ((bp = mpool_bkt(mp)) == NULL) + return (NULL); + + /* Read in the contents. */ +#ifdef STATISTICS + ++mp->pageread; +#endif + off = mp->pagesize * pgno; + if (lseek(mp->fd, off, SEEK_SET) != off) + return (NULL); + + if ((nr = read(mp->fd, bp->page, mp->pagesize)) != mp->pagesize) { + if (nr > 0) { + /* A partial read is definitely bad. */ + errno = EINVAL; + return (NULL); + } else { + /* + * A zero-length reads, means you need to create a + * new page. + */ + memset(bp->page, 0, mp->pagesize); + } + } + + /* Set the page number, pin the page. */ + bp->pgno = pgno; + if (!(flags & MPOOL_IGNOREPIN)) + bp->flags = MPOOL_PINNED; + bp->flags |= MPOOL_INUSE; + + /* + * Add the page to the head of the hash chain and the tail + * of the lru chain. + */ + head = &mp->hqh[HASHKEY(bp->pgno)]; + CIRCLEQ_INSERT_HEAD(head, bp, hq); + CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q); + + /* Run through the user's filter. */ + if (mp->pgin != NULL) + (mp->pgin)(mp->pgcookie, bp->pgno, bp->page); + + return (bp->page); +} + +/* + * mpool_put + * Return a page. + */ +int +mpool_put(mp, page, flags) + MPOOL *mp; + void *page; + u_int flags; +{ + BKT *bp; + +#ifdef STATISTICS + ++mp->pageput; +#endif + bp = (BKT *)((char *)page - sizeof(BKT)); +#ifdef DEBUG + if (!(bp->flags & MPOOL_PINNED)) { + (void)fprintf(stderr, + "mpool_put: page %d not pinned\n", bp->pgno); + abort(); + } +#endif + bp->flags &= ~MPOOL_PINNED; + if (flags & MPOOL_DIRTY) + bp->flags |= flags & MPOOL_DIRTY; + return (RET_SUCCESS); +} + +/* + * mpool_close + * Close the buffer pool. + */ +int +mpool_close(mp) + MPOOL *mp; +{ + BKT *bp; + + /* Free up any space allocated to the lru pages. */ + while ((bp = mp->lqh.cqh_first) != (void *)&mp->lqh) { + CIRCLEQ_REMOVE(&mp->lqh, mp->lqh.cqh_first, q); + free(bp); + } + + /* Free the MPOOL cookie. */ + free(mp); + return (RET_SUCCESS); +} + +/* + * mpool_sync + * Sync the pool to disk. + */ +int +mpool_sync(mp) + MPOOL *mp; +{ + BKT *bp; + + /* Walk the lru chain, flushing any dirty pages to disk. */ + for (bp = mp->lqh.cqh_first; + bp != (void *)&mp->lqh; bp = bp->q.cqe_next) + if (bp->flags & MPOOL_DIRTY && + mpool_write(mp, bp) == RET_ERROR) + return (RET_ERROR); + + /* Sync the file descriptor. */ + return (fsync(mp->fd) ? RET_ERROR : RET_SUCCESS); +} + +/* + * mpool_bkt + * Get a page from the cache (or create one). + */ +static BKT * +mpool_bkt(mp) + MPOOL *mp; +{ + struct _hqh *head; + BKT *bp; + + /* If under the max cached, always create a new page. */ + if (mp->curcache < mp->maxcache) + goto new; + + /* + * If the cache is max'd out, walk the lru list for a buffer we + * can flush. If we find one, write it (if necessary) and take it + * off any lists. If we don't find anything we grow the cache anyway. + * The cache never shrinks. + */ + for (bp = mp->lqh.cqh_first; + bp != (void *)&mp->lqh; bp = bp->q.cqe_next) + if (!(bp->flags & MPOOL_PINNED)) { + /* Flush if dirty. */ + if (bp->flags & MPOOL_DIRTY && + mpool_write(mp, bp) == RET_ERROR) + return (NULL); +#ifdef STATISTICS + ++mp->pageflush; +#endif + /* Remove from the hash and lru queues. */ + head = &mp->hqh[HASHKEY(bp->pgno)]; + CIRCLEQ_REMOVE(head, bp, hq); + CIRCLEQ_REMOVE(&mp->lqh, bp, q); +#ifdef DEBUG + { void *spage; + spage = bp->page; + memset(bp, 0xff, sizeof(BKT) + mp->pagesize); + bp->page = spage; + } +#endif + bp->flags = 0; + return (bp); + } + +new: if ((bp = (BKT *)malloc(sizeof(BKT) + mp->pagesize)) == NULL) + return (NULL); +#ifdef STATISTICS + ++mp->pagealloc; +#endif +#if defined(DEBUG) || defined(PURIFY) + memset(bp, 0xff, sizeof(BKT) + mp->pagesize); +#endif + bp->page = (char *)bp + sizeof(BKT); + bp->flags = 0; + ++mp->curcache; + return (bp); +} + +/* + * mpool_write + * Write a page to disk. + */ +static int +mpool_write(mp, bp) + MPOOL *mp; + BKT *bp; +{ + off_t off; + +#ifdef STATISTICS + ++mp->pagewrite; +#endif + + /* Run through the user's filter. */ + if (mp->pgout) + (mp->pgout)(mp->pgcookie, bp->pgno, bp->page); + + off = mp->pagesize * bp->pgno; + if (lseek(mp->fd, off, SEEK_SET) != off) + return (RET_ERROR); + if (write(mp->fd, bp->page, mp->pagesize) != mp->pagesize) + return (RET_ERROR); + + bp->flags &= ~MPOOL_DIRTY; + return (RET_SUCCESS); +} + +/* + * mpool_look + * Lookup a page in the cache. + */ +static BKT * +mpool_look(mp, pgno) + MPOOL *mp; + db_pgno_t pgno; +{ + struct _hqh *head; + BKT *bp; + + head = &mp->hqh[HASHKEY(pgno)]; + for (bp = head->cqh_first; bp != (void *)head; bp = bp->hq.cqe_next) + if ((bp->pgno == pgno) && + (bp->flags & MPOOL_INUSE == MPOOL_INUSE)) { +#ifdef STATISTICS + ++mp->cachehit; +#endif + return (bp); + } +#ifdef STATISTICS + ++mp->cachemiss; +#endif + return (NULL); +} + +#ifdef STATISTICS +/* + * mpool_stat + * Print out cache statistics. + */ +void +mpool_stat(mp) + MPOOL *mp; +{ + BKT *bp; + int cnt; + char *sep; + + (void)fprintf(stderr, "%lu pages in the file\n", mp->npages); + (void)fprintf(stderr, + "page size %lu, cacheing %lu pages of %lu page max cache\n", + mp->pagesize, mp->curcache, mp->maxcache); + (void)fprintf(stderr, "%lu page puts, %lu page gets, %lu page new\n", + mp->pageput, mp->pageget, mp->pagenew); + (void)fprintf(stderr, "%lu page allocs, %lu page flushes\n", + mp->pagealloc, mp->pageflush); + if (mp->cachehit + mp->cachemiss) + (void)fprintf(stderr, + "%.0f%% cache hit rate (%lu hits, %lu misses)\n", + ((double)mp->cachehit / (mp->cachehit + mp->cachemiss)) + * 100, mp->cachehit, mp->cachemiss); + (void)fprintf(stderr, "%lu page reads, %lu page writes\n", + mp->pageread, mp->pagewrite); + + sep = ""; + cnt = 0; + for (bp = mp->lqh.cqh_first; + bp != (void *)&mp->lqh; bp = bp->q.cqe_next) { + (void)fprintf(stderr, "%s%d", sep, bp->pgno); + if (bp->flags & MPOOL_DIRTY) + (void)fprintf(stderr, "d"); + if (bp->flags & MPOOL_PINNED) + (void)fprintf(stderr, "P"); + if (++cnt == 10) { + sep = "\n"; + cnt = 0; + } else + sep = ", "; + + } + (void)fprintf(stderr, "\n"); +} +#endif |
