sys/fs/filecorefs/filecore_bmap.c

   1 /*      $NetBSD: filecore_bmap.c,v 1.8 2008/05/16 09:21:59 hannken Exp $        */
   2
   3 /*-
   4  * Copyright (c) 1994 The Regents of the University of California.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      filecore_bmap.c         1.1     1998/6/26
  32  */
  33
  34 /*-
  35  * Copyright (c) 1998 Andrew McMurry
  36  *
  37  * Redistribution and use in source and binary forms, with or without
  38  * modification, are permitted provided that the following conditions
  39  * are met:
  40  * 1. Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  * 2. Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in the
  44  *    documentation and/or other materials provided with the distribution.
  45  * 3. All advertising materials mentioning features or use of this software
  46  *    must display the following acknowledgement:
  47  *      This product includes software developed by the University of
  48  *      California, Berkeley and its contributors.
  49  * 4. Neither the name of the University nor the names of its contributors
  50  *    may be used to endorse or promote products derived from this software
  51  *    without specific prior written permission.
  52  *
  53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  63  * SUCH DAMAGE.
  64  *
  65  *      filecore_bmap.c         1.1     1998/6/26
  66  */
  67
  68 #include <sys/cdefs.h>
  69 __KERNEL_RCSID(0, "$NetBSD: filecore_bmap.c,v 1.8 2008/05/16 09:21:59 hannken Exp $");
  70
  71 #include <sys/param.h>
  72 #include <sys/systm.h>
  73 #include <sys/namei.h>
  74 #include <sys/buf.h>
  75 #include <sys/file.h>
  76 #include <sys/vnode.h>
  77 #include <sys/mount.h>
  78 #include <sys/kauth.h>
  79
  80 #include <fs/filecorefs/filecore.h>
  81 #include <fs/filecorefs/filecore_extern.h>
  82 #include <fs/filecorefs/filecore_node.h>
  83
  84 /*
  85  * Bmap converts a the logical block number of a file to its physical block
  86  * number on the disk. The conversion is done by using the logical block
  87  * number to index into the data block (extent) for the file.
  88  */
  89 int
  90 filecore_bmap(void *v)
  91 {
  92         struct vop_bmap_args /* {
  93                 struct vnode *a_vp;
  94                 daddr_t a_bn;
  95                 struct vnode **a_vpp;
  96                 daddr_t *a_bnp;
  97                 int *a_runp;
  98         } */ *ap = v;
  99         struct filecore_node *ip = VTOI(ap->a_vp);
 100         struct filecore_mnt *fcmp = ip->i_mnt;
 101         daddr_t lbn = ap->a_bn;
 102
 103         /*
 104          * Check for underlying vnode requests and ensure that logical
 105          * to physical mapping is requested.
 106          */
 107         if (ap->a_vpp != NULL)
 108                 *ap->a_vpp = ip->i_devvp;
 109         if (ap->a_bnp == NULL)
 110                 return (0);
 111
 112         /*
 113          * Determine maximum number of readahead blocks following the
 114          * requested block.
 115          */
 116         if (ap->a_runp) {
 117                 int nblk;
 118                 int bshift=fcmp->log2bsize;
 119
 120                 nblk = (ip->i_size >> bshift) - (lbn + 1);
 121                 if (nblk <= 0)
 122                         *ap->a_runp = 0;
 123                 else if (nblk >= (MAXBSIZE >> bshift))
 124                         *ap->a_runp = (MAXBSIZE >> bshift) - 1;
 125                 else
 126                         *ap->a_runp = nblk;
 127         }
 128         /*
 129          * Compute the requested block number
 130          */
 131         return filecore_map(fcmp, ip->i_dirent.addr, lbn, ap->a_bnp);
 132 }
 133
 134 int
 135 filecore_map(struct filecore_mnt *fcmp, u_int32_t addr, daddr_t lbn, daddr_t *bnp)
 136 {
 137         struct buf *bp;
 138         u_long frag, sect, zone, izone, a, b, m, n;
 139         u_int64_t zaddr;
 140         u_long *ptr;
 141         long c;
 142         int error = 0;
 143
 144 #ifdef FILECORE_DEBUG
 145         printf("filecore_map(addr=%x, lbn=%llx)\n", addr, (long long)lbn);
 146 #endif
 147         frag = addr >> 8;
 148         sect = (addr & 0xff) +
 149                 ((lbn << fcmp->log2bsize) >> fcmp->drec.log2secsize);
 150         if (frag != 2)
 151                 zone = frag / fcmp->idspz;
 152         else
 153                 zone = fcmp->drec.nzones / 2;
 154         izone = zone;
 155         if (zone != 0)
 156                 zaddr=((8<<fcmp->drec.log2secsize)-fcmp->drec.zone_spare)*zone
 157                   - 8*FILECORE_DISCREC_SIZE;
 158         else
 159                 zaddr = 0;
 160         if (sect > 0)
 161                 sect--;
 162         sect <<= fcmp->drec.share_size;
 163         do {
 164                 error=bread(fcmp->fc_devvp, fcmp->map + zone,
 165                             1 << fcmp->drec.log2secsize, NOCRED, 0, &bp);
 166 #ifdef FILECORE_DEBUG_BR
 167                 printf("bread(%p, %lx, %d, CRED, %p)=%d\n", fcmp->fc_devvp,
 168                        fcmp->map+zone, 1 << fcmp->drec.log2secsize, bp, error);
 169                 printf("block is at %p\n", bp->b_data);
 170 #endif
 171                 if (error != 0) {
 172 #ifdef FILECORE_DEBUG_BR
 173                         printf("brelse(%p) bm1\n", bp);
 174 #endif
 175                         brelse(bp, 0);
 176                         return error;
 177                 }
 178                 ptr = (u_long *)(bp->b_data) + 1; /* skip map zone header */
 179                 if (zone == 0)
 180                         ptr += FILECORE_DISCREC_SIZE >> 2;
 181                 b = 0;
 182                 while (b < (8 << (fcmp->drec.log2secsize))
 183                    - fcmp->drec.zone_spare) {
 184                         a = ptr[b >> 5] >> (b & 31);
 185                         c = 32 - (b & 31) - fcmp->drec.idlen;
 186                         if (c <= 0) {
 187                                 m = ptr[(b >> 5) + 1];
 188                                 a |= m << (fcmp->drec.idlen+c);
 189                                 m >>= -c;
 190                                 c += 32;
 191                         } else
 192                                 m = a >> fcmp->drec.idlen;
 193                         n = fcmp->drec.idlen + 1;
 194                         while ((m & 1) == 0) {
 195                                 m >>= 1;
 196                                 n++;
 197                                 if (--c == 0) {
 198                                         c=32;
 199                                         m = ptr[(b + n - 1) >> 5];
 200                                 }
 201                         }
 202                         a &= fcmp->mask;
 203                         if (a == frag) {
 204                                 if (sect << fcmp->drec.log2secsize < n
 205                                     << fcmp->drec.log2bpmb) {
 206                                         *bnp = (((zaddr+b)
 207                                             << fcmp->drec.log2bpmb)
 208                                             >> fcmp->drec.log2secsize) + sect;
 209
 210 #ifdef FILECORE_DEBUG_BR
 211                                         printf("brelse(%p) bm2\n", bp);
 212 #endif
 213                                         brelse(bp, 0);
 214                                         return 0;
 215                                 } else
 216                                         sect -= (n<<fcmp->drec.log2bpmb)
 217                                             >> fcmp->drec.log2secsize;
 218                         }
 219                         b += n;
 220                 }
 221 #ifdef FILECORE_DEBUG_BR
 222                 printf("brelse(%p) bm3\n", bp);
 223 #endif
 224                 brelse(bp, 0);
 225                 if (++zone == fcmp->drec.nzones) {
 226                         zone = 0;
 227                         zaddr=0;
 228                 } else
 229                         zaddr += ((8 << fcmp->drec.log2secsize)
 230                             - fcmp->drec.zone_spare);
 231         } while (zone != izone);
 232         return (E2BIG);
 233 }
 234
 235 int
 236 filecore_bread(struct filecore_mnt *fcmp, u_int32_t addr, int size, kauth_cred_t cred, struct buf **bp)
 237 {
 238         int error = 0;
 239         daddr_t bn;
 240
 241         error = filecore_map(fcmp, addr, 0, &bn);
 242         if (error) {
 243
 244 #ifdef FILECORE_DEBUG
 245                 printf("filecore_bread(error=%d)\n", error);
 246 #endif
 247                 return error;
 248         }
 249         error = bread(fcmp->fc_devvp, bn, size, cred, 0, bp);
 250 #ifdef FILECORE_DEBUG_BR
 251         printf("bread(%p, %llx, %d, CRED, %p)=%d\n", fcmp->fc_devvp,
 252             (long long)bn, size, *bp, error);
 253 #endif
 254         return error;
 255 }
 256
 257 int
 258 filecore_dbread(struct filecore_node *ip, struct buf **bp)
 259 {
 260         int error = 0;
 261
 262         if (ip->i_block == -1)
 263                 error = filecore_map(ip->i_mnt, ip->i_dirent.addr,
 264                         0, &(ip->i_block));
 265         if (error)
 266                 return error;
 267         error = bread(ip->i_mnt->fc_devvp, ip->i_block, FILECORE_DIR_SIZE,
 268                       NOCRED, 0, bp);
 269 #ifdef FILECORE_DEBUG_BR
 270         printf("bread(%p, %llx, %d, CRED, %p)=%d\n", ip->i_mnt->fc_devvp,
 271                (long long)ip->i_block, FILECORE_DIR_SIZE, *bp, error);
 272 #endif
 273         return error;
 274 }