The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/geom/geom_vol_ffs.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (c) 2002, 2003 Gordon Tetlow
    3  * All rights reserved.
    4  *
    5  * Redistribution and use in source and binary forms, with or without
    6  * modification, are permitted provided that the following conditions
    7  * are met:
    8  * 1. Redistributions of source code must retain the above copyright
    9  *    notice, this list of conditions and the following disclaimer.
   10  * 2. Redistributions in binary form must reproduce the above copyright
   11  *    notice, this list of conditions and the following disclaimer in the
   12  *    documentation and/or other materials provided with the distribution.
   13  *
   14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   24  * SUCH DAMAGE.
   25  */
   26 
   27 #include <sys/cdefs.h>
   28 __FBSDID("$FreeBSD: releng/9.1/sys/geom/geom_vol_ffs.c 219029 2011-02-25 10:24:35Z netchild $");
   29 
   30 #include <sys/param.h>
   31 #include <sys/errno.h>
   32 #include <sys/systm.h>
   33 #include <sys/sysctl.h>
   34 #include <sys/kernel.h>
   35 #include <sys/malloc.h>
   36 #include <sys/bio.h>
   37 #include <sys/lock.h>
   38 #include <sys/mutex.h>
   39 
   40 #include <ufs/ufs/dinode.h>
   41 #include <ufs/ffs/fs.h>
   42 
   43 #include <geom/geom.h>
   44 #include <geom/geom_slice.h>
   45 
   46 FEATURE(geom_vol, "GEOM support for volume names from UFS superblock");
   47 
   48 #define VOL_FFS_CLASS_NAME "VOL_FFS"
   49 
   50 static int superblocks[] = SBLOCKSEARCH;
   51 
   52 struct g_vol_ffs_softc {
   53         char *  vol;
   54 };
   55 
   56 static int
   57 g_vol_ffs_start(struct bio *bp __unused)
   58 {
   59         return(0);
   60 }
   61 
   62 static struct g_geom *
   63 g_vol_ffs_taste(struct g_class *mp, struct g_provider *pp, int flags)
   64 {
   65         struct g_geom *gp;
   66         struct g_consumer *cp;
   67         struct g_vol_ffs_softc *ms;
   68         int sb, superblock;
   69         struct fs *fs;
   70 
   71         g_trace(G_T_TOPOLOGY, "vol_taste(%s,%s)", mp->name, pp->name);
   72         g_topology_assert();
   73 
   74         /* 
   75          * XXX This is a really weak way to make sure we don't recurse.
   76          * Probably ought to use BIO_GETATTR to check for this.
   77          */
   78         if (flags == G_TF_NORMAL &&
   79             !strcmp(pp->geom->class->name, VOL_FFS_CLASS_NAME))
   80                 return (NULL);
   81 
   82         gp = g_slice_new(mp, 1, pp, &cp, &ms, sizeof(*ms), g_vol_ffs_start);
   83         if (gp == NULL)
   84                 return (NULL);
   85         g_topology_unlock();
   86         /*
   87          * Walk through the standard places that superblocks hide and look
   88          * for UFS magic. If we find magic, then check that the size in the
   89          * superblock corresponds to the size of the underlying provider.
   90          * Finally, look for a volume label and create an appropriate 
   91          * provider based on that.
   92          */
   93         for (sb=0; (superblock = superblocks[sb]) != -1; sb++) {
   94                 /*
   95                  * Take care not to issue an invalid I/O request.  The
   96                  * offset and size of the superblock candidate must be
   97                  * multiples of the provider's sector size, otherwise an
   98                  * FFS can't exist on the provider anyway.
   99                  */
  100                 if (superblock % cp->provider->sectorsize != 0 ||
  101                     SBLOCKSIZE % cp->provider->sectorsize != 0)
  102                         continue;
  103 
  104                 fs = (struct fs *) g_read_data(cp, superblock,
  105                         SBLOCKSIZE, NULL);
  106                 if (fs == NULL)
  107                         continue;
  108                 /* Check for magic and make sure things are the right size */
  109                 if (fs->fs_magic == FS_UFS1_MAGIC) {
  110                         if (fs->fs_old_size * fs->fs_fsize !=
  111                             (int32_t) pp->mediasize) {
  112                                 g_free(fs);
  113                                 continue;
  114                         }
  115                 } else if (fs->fs_magic == FS_UFS2_MAGIC) {
  116                         if (fs->fs_size * fs->fs_fsize !=
  117                             (int64_t) pp->mediasize) {
  118                                 g_free(fs);
  119                                 continue;
  120                         }
  121                 } else {
  122                         g_free(fs);
  123                         continue;
  124                 }
  125                 /* Check for volume label */
  126                 if (fs->fs_volname[0] == '\0') {
  127                         g_free(fs);
  128                         continue;
  129                 }
  130                 /* XXX We need to check for namespace conflicts. */
  131                 /* XXX How do you handle a mirror set? */
  132                 /* XXX We don't validate the volume name. */
  133                 g_topology_lock();
  134                 /* Alright, we have a label and a volume name, reconfig. */
  135                 g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t) 0,
  136                     pp->mediasize, pp->sectorsize, "vol/%s",
  137                     fs->fs_volname);
  138                 g_free(fs);
  139                 g_topology_unlock();
  140                 break;
  141         }
  142         g_topology_lock();
  143         g_access(cp, -1, 0, 0);
  144         if (LIST_EMPTY(&gp->provider)) {
  145                 g_slice_spoiled(cp);
  146                 return (NULL);
  147         }
  148         return (gp);
  149 }
  150 
  151 static struct g_class g_vol_ffs_class   = {
  152         .name = VOL_FFS_CLASS_NAME,
  153         .version = G_VERSION,
  154         .taste = g_vol_ffs_taste,
  155 };
  156 
  157 DECLARE_GEOM_CLASS(g_vol_ffs_class, g_vol_ffs);

Cache object: 8370ae9bdd80ddd2fdb31726e7690049


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.