spa_boot.c revision e7cbe64f7a72dae5cb44f100db60ca88f3313c65
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/spa.h>
#include <sys/sunddi.h>
char *
spa_get_bootfs()
{
char *zfs_bp;
if (ddi_prop_lookup_string(DDI_DEV_T_ANY, ddi_root_node(),
DDI_PROP_DONTPASS, "zfs-bootfs", &zfs_bp) !=
DDI_SUCCESS)
return (NULL);
return (zfs_bp);
}
void
spa_free_bootfs(char *bootfs)
{
ddi_prop_free(bootfs);
}
/*
* Calculate how many device pathnames are in devpath_list.
* The devpath_list could look like this:
*
* "/pci@1f,0/ide@d/disk@0,0:a /pci@1f,o/ide@d/disk@2,0:a"
*/
static int
spa_count_devpath(char *devpath_list)
{
int numpath;
char *tmp_path, *blank;
numpath = 0;
tmp_path = devpath_list;
/* skip leading blanks */
while (*tmp_path == ' ')
tmp_path++;
while ((blank = strchr(tmp_path, ' ')) != NULL) {
numpath++;
/* skip contiguous blanks */
while (*blank == ' ')
blank++;
tmp_path = blank;
}
if (strlen(tmp_path) > 0)
numpath++;
return (numpath);
}
/*
* Only allow booting the device if it has the same vdev information as
* the most recently updated vdev (highest txg) and is in a valid state.
*
* GRUB passes online/active device path names, e.g.
* "/pci@1f,0/ide@d/disk@0,0:a /pci@1f,o/ide@d/disk@2,0:a"
* to the kernel. The best vdev should have the same matching online/active
* list as what GRUB passes in.
*/
static int
spa_check_devstate(char *devpath_list, char *dev, nvlist_t *conf)
{
nvlist_t *nvtop, **child;
uint_t label_path, grub_path, c, children;
char *type;
VERIFY(nvlist_lookup_nvlist(conf, ZPOOL_CONFIG_VDEV_TREE,
&nvtop) == 0);
VERIFY(nvlist_lookup_string(nvtop, ZPOOL_CONFIG_TYPE, &type) == 0);
if (strcmp(type, VDEV_TYPE_DISK) == 0)
return (spa_rootdev_validate(nvtop)? 0 : EINVAL);
ASSERT(strcmp(type, VDEV_TYPE_MIRROR) == 0);
VERIFY(nvlist_lookup_nvlist_array(nvtop, ZPOOL_CONFIG_CHILDREN,
&child, &children) == 0);
/*
* Check if the devpath_list is the same as the path list in conf.
* If these two lists are different, then the booting device is not an
* up-to-date device that can be booted.
*/
label_path = 0;
for (c = 0; c < children; c++) {
char *physpath;
if (nvlist_lookup_string(child[c], ZPOOL_CONFIG_PHYS_PATH,
&physpath) != 0)
return (EINVAL);
if (spa_rootdev_validate(child[c])) {
if (strstr(devpath_list, physpath) == NULL)
return (EINVAL);
label_path++;
} else {
char *blank;
if (blank = strchr(dev, ' '))
*blank = '\0';
if (strcmp(physpath, dev) == 0)
return (EINVAL);
if (blank)
*blank = ' ';
}
}
grub_path = spa_count_devpath(devpath_list);
if (label_path != grub_path)
return (EINVAL);
return (0);
}
/*
* Given a list of vdev physpath names, pick the vdev with the most recent txg,
* and return the point of the device's physpath in the list and the device's
* label configuration. The content of the label would be the most recent
* updated information.
*/
int
spa_get_rootconf(char *devpath_list, char **bestdev, nvlist_t **bestconf)
{
nvlist_t *conf = NULL;
char *dev = NULL;
uint64_t txg = 0;
char *devpath, *blank;
devpath = devpath_list;
dev = devpath;
while (devpath[0] == ' ')
devpath++;
while ((blank = strchr(devpath, ' ')) != NULL) {
*blank = '\0';
spa_check_rootconf(devpath, &dev, &conf, &txg);
*blank = ' ';
while (*blank == ' ')
blank++;
devpath = blank;
}
/* for the only or the last devpath in the devpath_list */
if (strlen(devpath) > 0)
spa_check_rootconf(devpath, &dev, &conf, &txg);
if (conf == NULL)
return (EINVAL);
/*
* dev/conf is the vdev with the most recent txg.
* Check if the device is in a bootable state.
* dev may have a trailing blank since it points to a string
* in the devpath_list.
*/
if (spa_check_devstate(devpath_list, dev, conf) != 0)
return (EINVAL);
*bestdev = dev;
*bestconf = conf;
return (0);
}