geom_vol_ffs.c revision 114508
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 * $FreeBSD: head/sys/geom/geom_vol_ffs.c 114508 2003-05-02 06:36:14Z phk $ 27 */ 28 29#include <sys/param.h> 30#include <sys/errno.h> 31#include <sys/systm.h> 32#include <sys/kernel.h> 33#include <sys/malloc.h> 34#include <sys/bio.h> 35#include <sys/lock.h> 36#include <sys/mutex.h> 37 38#include <ufs/ufs/dinode.h> 39#include <ufs/ffs/fs.h> 40 41#include <geom/geom.h> 42#include <geom/geom_slice.h> 43 44#define VOL_FFS_CLASS_NAME "VOL_FFS" 45 46static int superblocks[] = SBLOCKSEARCH; 47 48struct g_vol_ffs_softc { 49 char * vol; 50}; 51 52static int 53g_vol_ffs_start(struct bio *bp __unused) 54{ 55 return(0); 56} 57 58static struct g_geom * 59g_vol_ffs_taste(struct g_class *mp, struct g_provider *pp, int flags) 60{ 61 struct g_geom *gp; 62 struct g_consumer *cp; 63 struct g_vol_ffs_softc *ms; 64 int error, sb, superblock; 65 struct fs *fs; 66 67 g_trace(G_T_TOPOLOGY, "vol_taste(%s,%s)", mp->name, pp->name); 68 g_topology_assert(); 69 70 /* 71 * XXX This is a really weak way to make sure we don't recurse. 72 * Probably ought to use BIO_GETATTR to check for this. 73 */ 74 if (flags == G_TF_NORMAL && 75 !strcmp(pp->geom->class->name, VOL_FFS_CLASS_NAME)) 76 return (NULL); 77 78 gp = g_slice_new(mp, 1, pp, &cp, &ms, sizeof(*ms), g_vol_ffs_start); 79 if (gp == NULL) 80 return (NULL); 81 g_topology_unlock(); 82 /* 83 * Walk through the standard places that superblocks hide and look 84 * for UFS magic. If we find magic, then check that the size in the 85 * superblock corresponds to the size of the underlying provider. 86 * Finally, look for a volume label and create an appropriate 87 * provider based on that. 88 */ 89 for (sb=0; (superblock = superblocks[sb]) != -1; sb++) { 90 fs = (struct fs *) g_read_data(cp, superblock, 91 SBLOCKSIZE, &error); 92 if (fs == NULL) 93 continue; 94 if (error != 0) { 95 g_free(fs); 96 continue; 97 } 98 /* Check for magic and make sure things are the right size */ 99 if (fs->fs_magic == FS_UFS1_MAGIC) { 100 if (fs->fs_old_size * fs->fs_fsize != 101 (int32_t) pp->mediasize) { 102 g_free(fs); 103 continue; 104 } 105 } else if (fs->fs_magic == FS_UFS2_MAGIC) { 106 if (fs->fs_size * fs->fs_fsize != 107 (int64_t) pp->mediasize) { 108 g_free(fs); 109 continue; 110 } 111 } else { 112 g_free(fs); 113 continue; 114 } 115 /* Check for volume label */ 116 if (fs->fs_volname[0] == '\0') { 117 g_free(fs); 118 continue; 119 } 120 /* XXX We need to check for namespace conflicts. */ 121 /* XXX How do you handle a mirror set? */ 122 /* XXX We don't validate the volume name. */ 123 g_topology_lock(); 124 /* Alright, we have a label and a volume name, reconfig. */ 125 g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t) 0, 126 pp->mediasize, pp->sectorsize, "vol/%s", 127 fs->fs_volname); 128 g_free(fs); 129 g_topology_unlock(); 130 break; 131 } 132 g_topology_lock(); 133 g_access_rel(cp, -1, 0, 0); 134 if (LIST_EMPTY(&gp->provider)) { 135 g_slice_spoiled(cp); 136 return (NULL); 137 } 138 return (gp); 139} 140 141static struct g_class g_vol_ffs_class = { 142 .name = VOL_FFS_CLASS_NAME, 143 .taste = g_vol_ffs_taste, 144 G_CLASS_INITIALIZER 145}; 146 147DECLARE_GEOM_CLASS(g_vol_ffs_class, g_vol_ffs); 148