diff options
Diffstat (limited to 'usr.sbin/makefs/ffs/buf.c')
| -rw-r--r-- | usr.sbin/makefs/ffs/buf.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/usr.sbin/makefs/ffs/buf.c b/usr.sbin/makefs/ffs/buf.c new file mode 100644 index 000000000000..5fdb517208f9 --- /dev/null +++ b/usr.sbin/makefs/ffs/buf.c @@ -0,0 +1,219 @@ +/* $NetBSD: buf.c,v 1.13 2004/06/20 22:20:18 jmc Exp $ */ + +/*- + * SPDX-License-Identifier: BSD-4-Clause + * + * Copyright (c) 2001 Wasabi Systems, Inc. + * All rights reserved. + * + * Written by Luke Mewburn for Wasabi Systems, Inc. + * + * 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 for the NetBSD Project by + * Wasabi Systems, Inc. + * 4. The name of Wasabi Systems, Inc. may not be used to endorse + * or promote products derived from this software without specific prior + * written permission. + * + * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC + * 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. + */ + +#include <sys/param.h> +#include <sys/time.h> + +#include <assert.h> +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <util.h> + +#include "makefs.h" +#include "buf.h" + +static TAILQ_HEAD(buftailhead, m_buf) buftail; + +int +bread(struct m_vnode *vp, daddr_t blkno, int size, struct ucred *u1 __unused, + struct m_buf **bpp) +{ + off_t offset; + ssize_t rv; + fsinfo_t *fs = vp->fs; + + assert (bpp != NULL); + + if (debug & DEBUG_BUF_BREAD) + printf("%s: blkno %lld size %d\n", __func__, (long long)blkno, + size); + *bpp = getblk(vp, blkno, size, 0, 0, 0); + offset = (off_t)(*bpp)->b_blkno * fs->sectorsize + fs->offset; + if (debug & DEBUG_BUF_BREAD) + printf("%s: blkno %lld offset %lld bcount %ld\n", __func__, + (long long)(*bpp)->b_blkno, (long long) offset, + (*bpp)->b_bcount); + if (lseek((*bpp)->b_fs->fd, offset, SEEK_SET) == -1) + err(1, "%s: lseek %lld (%lld)", __func__, + (long long)(*bpp)->b_blkno, (long long)offset); + rv = read((*bpp)->b_fs->fd, (*bpp)->b_data, (size_t)(*bpp)->b_bcount); + if (debug & DEBUG_BUF_BREAD) + printf("%s: read %ld (%lld) returned %d\n", __func__, + (*bpp)->b_bcount, (long long)offset, (int)rv); + if (rv == -1) /* read error */ + err(1, "%s: read %ld (%lld) returned %d", __func__, + (*bpp)->b_bcount, (long long)offset, (int)rv); + else if (rv != (*bpp)->b_bcount) /* short read */ + err(1, "%s: read %ld (%lld) returned %d", __func__, + (*bpp)->b_bcount, (long long)offset, (int)rv); + else + return (0); +} + +void +brelse(struct m_buf *bp) +{ + + assert (bp != NULL); + assert (bp->b_data != NULL); + + if (bp->b_lblkno < 0) { + /* + * XXX don't remove any buffers with negative logical block + * numbers (lblkno), so that we retain the mapping + * of negative lblkno -> real blkno that ffs_balloc() + * sets up. + * + * if we instead released these buffers, and implemented + * ufs_strategy() (and ufs_bmaparray()) and called those + * from bread() and bwrite() to convert the lblkno to + * a real blkno, we'd add a lot more code & complexity + * and reading off disk, for little gain, because this + * simple hack works for our purpose. + */ + bp->b_bcount = 0; + return; + } + + TAILQ_REMOVE(&buftail, bp, b_tailq); + free(bp->b_data); + free(bp); +} + +int +bwrite(struct m_buf *bp) +{ + off_t offset; + ssize_t rv; + size_t bytes; + int e; + fsinfo_t *fs = bp->b_fs; + + assert (bp != NULL); + offset = (off_t)bp->b_blkno * fs->sectorsize + fs->offset; + bytes = (size_t)bp->b_bcount; + if (debug & DEBUG_BUF_BWRITE) + printf("%s: blkno %lld offset %lld bcount %zu\n", __func__, + (long long)bp->b_blkno, (long long) offset, bytes); + if (lseek(bp->b_fs->fd, offset, SEEK_SET) == -1) { + brelse(bp); + return (errno); + } + rv = write(bp->b_fs->fd, bp->b_data, bytes); + e = errno; + if (debug & DEBUG_BUF_BWRITE) + printf("%s: write %ld (offset %lld) returned %lld\n", __func__, + bp->b_bcount, (long long)offset, (long long)rv); + brelse(bp); + if (rv == (ssize_t)bytes) + return (0); + if (rv == -1) /* write error */ + return (e); + return (EAGAIN); +} + +void +bcleanup(void) +{ + struct m_buf *bp; + + /* + * XXX this really shouldn't be necessary, but i'm curious to + * know why there's still some buffers lying around that + * aren't brelse()d + */ + + if (TAILQ_EMPTY(&buftail)) + return; + + printf("%s: unflushed buffers:\n", __func__); + TAILQ_FOREACH(bp, &buftail, b_tailq) { + printf("\tlblkno %10lld blkno %10lld count %6ld bufsize %6ld\n", + (long long)bp->b_lblkno, (long long)bp->b_blkno, + bp->b_bcount, bp->b_bufsize); + } + printf("%s: done\n", __func__); +} + +struct m_buf * +getblk(struct m_vnode *vp, daddr_t blkno, int size, int u1 __unused, + int u2 __unused, int u3 __unused) +{ + static int buftailinitted; + struct m_buf *bp; + void *n; + + if (debug & DEBUG_BUF_GETBLK) + printf("%s: blkno %lld size %d\n", __func__, (long long)blkno, + size); + + bp = NULL; + if (!buftailinitted) { + if (debug & DEBUG_BUF_GETBLK) + printf("%s: initialising tailq\n", __func__); + TAILQ_INIT(&buftail); + buftailinitted = 1; + } else { + TAILQ_FOREACH(bp, &buftail, b_tailq) { + if (bp->b_lblkno != blkno) + continue; + break; + } + } + if (bp == NULL) { + bp = ecalloc(1, sizeof(*bp)); + bp->b_bufsize = 0; + bp->b_blkno = bp->b_lblkno = blkno; + bp->b_fs = vp->fs; + bp->b_data = NULL; + TAILQ_INSERT_HEAD(&buftail, bp, b_tailq); + } + bp->b_bcount = size; + if (bp->b_data == NULL || bp->b_bcount > bp->b_bufsize) { + n = erealloc(bp->b_data, (size_t)size); + memset(n, 0, (size_t)size); + bp->b_data = n; + bp->b_bufsize = size; + } + + return (bp); +} |