freebsd-skq/sys/geom/geom_vol_ffs.c

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/*-
* Copyright (c) 2002, 2003 Gordon Tetlow
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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.
*/
2003-06-11 06:49:16 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#include <geom/geom.h>
#include <geom/geom_slice.h>
#define VOL_FFS_CLASS_NAME "VOL_FFS"
static int superblocks[] = SBLOCKSEARCH;
struct g_vol_ffs_softc {
char * vol;
};
static int
g_vol_ffs_start(struct bio *bp __unused)
{
return(0);
}
static struct g_geom *
g_vol_ffs_taste(struct g_class *mp, struct g_provider *pp, int flags)
{
struct g_geom *gp;
struct g_consumer *cp;
struct g_vol_ffs_softc *ms;
int error, sb, superblock;
struct fs *fs;
g_trace(G_T_TOPOLOGY, "vol_taste(%s,%s)", mp->name, pp->name);
g_topology_assert();
/*
* XXX This is a really weak way to make sure we don't recurse.
* Probably ought to use BIO_GETATTR to check for this.
*/
if (flags == G_TF_NORMAL &&
!strcmp(pp->geom->class->name, VOL_FFS_CLASS_NAME))
return (NULL);
gp = g_slice_new(mp, 1, pp, &cp, &ms, sizeof(*ms), g_vol_ffs_start);
if (gp == NULL)
return (NULL);
g_topology_unlock();
/*
* Walk through the standard places that superblocks hide and look
* for UFS magic. If we find magic, then check that the size in the
* superblock corresponds to the size of the underlying provider.
* Finally, look for a volume label and create an appropriate
* provider based on that.
*/
for (sb=0; (superblock = superblocks[sb]) != -1; sb++) {
fs = (struct fs *) g_read_data(cp, superblock,
SBLOCKSIZE, &error);
if (fs == NULL || error != 0)
continue;
/* Check for magic and make sure things are the right size */
if (fs->fs_magic == FS_UFS1_MAGIC) {
if (fs->fs_old_size * fs->fs_fsize !=
(int32_t) pp->mediasize) {
g_free(fs);
continue;
}
} else if (fs->fs_magic == FS_UFS2_MAGIC) {
if (fs->fs_size * fs->fs_fsize !=
(int64_t) pp->mediasize) {
g_free(fs);
continue;
}
} else {
g_free(fs);
continue;
}
/* Check for volume label */
if (fs->fs_volname[0] == '\0') {
g_free(fs);
continue;
}
/* XXX We need to check for namespace conflicts. */
/* XXX How do you handle a mirror set? */
/* XXX We don't validate the volume name. */
g_topology_lock();
/* Alright, we have a label and a volume name, reconfig. */
g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t) 0,
pp->mediasize, pp->sectorsize, "vol/%s",
fs->fs_volname);
g_free(fs);
g_topology_unlock();
break;
}
g_topology_lock();
g_access_rel(cp, -1, 0, 0);
if (LIST_EMPTY(&gp->provider)) {
g_slice_spoiled(cp);
return (NULL);
}
return (gp);
}
static struct g_class g_vol_ffs_class = {
.name = VOL_FFS_CLASS_NAME,
.taste = g_vol_ffs_taste,
};
DECLARE_GEOM_CLASS(g_vol_ffs_class, g_vol_ffs);