usr.sbin/makefs/ffs/buf.c

   1 /*      $NetBSD: buf.c,v 1.11 2003/10/16 06:31:38 itojun Exp $  */
   2
   3 /*
   4  * Copyright (c) 2001 Wasabi Systems, Inc.
   5  * All rights reserved.
   6  *
   7  * Written by Luke Mewburn for Wasabi Systems, Inc.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed for the NetBSD Project by
  20  *      Wasabi Systems, Inc.
  21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
  22  *    or promote products derived from this software without specific prior
  23  *    written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
  29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  35  * POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 #if HAVE_NBTOOL_CONFIG_H
  39 #include "nbtool_config.h"
  40 #endif
  41
  42 #include <sys/cdefs.h>
  43 #if defined(__RCSID) && !defined(__lint)
  44 __RCSID("$NetBSD: buf.c,v 1.11 2003/10/16 06:31:38 itojun Exp $");
  45 #endif  /* !__lint */
  46
  47 #include <sys/param.h>
  48 #include <sys/time.h>
  49
  50 #include <assert.h>
  51 #include <errno.h>
  52 #include <stdio.h>
  53 #include <stdlib.h>
  54 #include <unistd.h>
  55
  56 #include "makefs.h"
  57
  58 #include <ufs/ufs/dinode.h>
  59 #include <ufs/ffs/fs.h>
  60
  61 #include "ffs/buf.h"
  62 #include "ffs/ufs_inode.h"
  63
  64 extern int sectorsize;          /* XXX: from ffs.c & mkfs.c */
  65
  66 TAILQ_HEAD(buftailhead,buf) buftail;
  67
  68 int
  69 bread(int fd, struct fs *fs, daddr_t blkno, int size, struct buf **bpp)
  70 {
  71         off_t   offset;
  72         ssize_t rv;
  73
  74         assert (fs != NULL);
  75         assert (bpp != NULL);
  76
  77         if (debug & DEBUG_BUF_BREAD)
  78                 printf("bread: fs %p blkno %lld size %d\n",
  79                     fs, (long long)blkno, size);
  80         *bpp = getblk(fd, fs, blkno, size);
  81         offset = (*bpp)->b_blkno * sectorsize;  /* XXX */
  82         if (debug & DEBUG_BUF_BREAD)
  83                 printf("bread: bp %p blkno %lld offset %lld bcount %ld\n",
  84                     (*bpp), (long long)(*bpp)->b_blkno, (long long) offset,
  85                     (*bpp)->b_bcount);
  86         if (lseek((*bpp)->b_fd, offset, SEEK_SET) == -1)
  87                 err(1, "bread: lseek %lld (%lld)",
  88                     (long long)(*bpp)->b_blkno, (long long)offset);
  89         rv = read((*bpp)->b_fd, (*bpp)->b_data, (*bpp)->b_bcount);
  90         if (debug & DEBUG_BUF_BREAD)
  91                 printf("bread: read %ld (%lld) returned %d\n",
  92                     (*bpp)->b_bcount, (long long)offset, (int)rv);
  93         if (rv == -1)                           /* read error */
  94                 err(1, "bread: read %ld (%lld) returned %d",
  95                     (*bpp)->b_bcount, (long long)offset, (int)rv);
  96         else if (rv != (*bpp)->b_bcount)        /* short read */
  97                 err(1, "bread: read %ld (%lld) returned %d",
  98                     (*bpp)->b_bcount, (long long)offset, (int)rv);
  99         else
 100                 return (0);
 101 }
 102
 103 void
 104 brelse(struct buf *bp)
 105 {
 106
 107         assert (bp != NULL);
 108         assert (bp->b_data != NULL);
 109
 110         if (bp->b_lblkno < 0) {
 111                 /*
 112                  * XXX  don't remove any buffers with negative logical block
 113                  *      numbers (lblkno), so that we retain the mapping
 114                  *      of negative lblkno -> real blkno that ffs_balloc()
 115                  *      sets up.
 116                  *
 117                  *      if we instead released these buffers, and implemented
 118                  *      ufs_strategy() (and ufs_bmaparray()) and called those
 119                  *      from bread() and bwrite() to convert the lblkno to
 120                  *      a real blkno, we'd add a lot more code & complexity
 121                  *      and reading off disk, for little gain, because this
 122                  *      simple hack works for our purpose.
 123                  */
 124                 bp->b_bcount = 0;
 125                 return;
 126         }
 127
 128         TAILQ_REMOVE(&buftail, bp, b_tailq);
 129         free(bp->b_data);
 130         free(bp);
 131 }
 132
 133 int
 134 bwrite(struct buf *bp)
 135 {
 136         off_t   offset;
 137         ssize_t rv;
 138
 139         assert (bp != NULL);
 140         offset = bp->b_blkno * sectorsize;      /* XXX */
 141         if (debug & DEBUG_BUF_BWRITE)
 142                 printf("bwrite: bp %p blkno %lld offset %lld bcount %ld\n",
 143                     bp, (long long)bp->b_blkno, (long long) offset,
 144                     bp->b_bcount);
 145         if (lseek(bp->b_fd, offset, SEEK_SET) == -1)
 146                 return (errno);
 147         rv = write(bp->b_fd, bp->b_data, bp->b_bcount);
 148         if (debug & DEBUG_BUF_BWRITE)
 149                 printf("bwrite: write %ld (offset %lld) returned %lld\n",
 150                     bp->b_bcount, (long long)offset, (long long)rv);
 151         if (rv == bp->b_bcount)
 152                 return (0);
 153         else if (rv == -1)              /* write error */
 154                 return (errno);
 155         else                            /* short write ? */
 156                 return (EAGAIN);
 157 }
 158
 159 void
 160 bcleanup(void)
 161 {
 162         struct buf *bp;
 163
 164         /*
 165          * XXX  this really shouldn't be necessary, but i'm curious to
 166          *      know why there's still some buffers lying around that
 167          *      aren't brelse()d
 168          */
 169
 170         if (TAILQ_EMPTY(&buftail))
 171                 return;
 172
 173         printf("bcleanup: unflushed buffers:\n");
 174         TAILQ_FOREACH(bp, &buftail, b_tailq) {
 175                 printf("\tlblkno %10lld  blkno %10lld  count %6ld  bufsize %6ld\n",
 176                     (long long)bp->b_lblkno, (long long)bp->b_blkno,
 177                     bp->b_bcount, bp->b_bufsize);
 178         }
 179         printf("bcleanup: done\n");
 180 }
 181
 182 struct buf *
 183 getblk(int fd, struct fs *fs, daddr_t blkno, int size)
 184 {
 185         static int buftailinitted;
 186         struct buf *bp;
 187         void *n;
 188
 189         assert (fs != NULL);
 190         if (debug & DEBUG_BUF_GETBLK)
 191                 printf("getblk: fs %p blkno %lld size %d\n", fs,
 192                     (long long)blkno, size);
 193
 194         bp = NULL;
 195         if (!buftailinitted) {
 196                 if (debug & DEBUG_BUF_GETBLK)
 197                         printf("getblk: initialising tailq\n");
 198                 TAILQ_INIT(&buftail);
 199                 buftailinitted = 1;
 200         } else {
 201                 TAILQ_FOREACH(bp, &buftail, b_tailq) {
 202                         if (bp->b_lblkno != blkno)
 203                                 continue;
 204                         break;
 205                 }
 206         }
 207         if (bp == NULL) {
 208                 if ((bp = calloc(1, sizeof(struct buf))) == NULL)
 209                         err(1, "getblk: calloc");
 210
 211                 bp->b_bufsize = 0;
 212                 bp->b_blkno = bp->b_lblkno = blkno;
 213                 bp->b_fd = fd;
 214                 bp->b_fs = fs;
 215                 bp->b_data = NULL;
 216                 TAILQ_INSERT_HEAD(&buftail, bp, b_tailq);
 217         }
 218         bp->b_bcount = size;
 219         if (bp->b_data == NULL || bp->b_bcount > bp->b_bufsize) {
 220                 n = realloc(bp->b_data, size);
 221                 if (n == NULL)
 222                         err(1, "getblk: realloc b_data %ld", bp->b_bcount);
 223                 bp->b_data = n;
 224                 bp->b_bufsize = size;
 225         }
 226
 227         return (bp);
 228 }