lib/libdevinfo/devfsinfo.c

/*
 * 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 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <stdlib.h>
#include <thread.h>
#include <synch.h>
#include <sys/types.h>
#include <ctype.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/modctl.h>
#include <errno.h>
#include <sys/openpromio.h>
#include <ftw.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <limits.h>

#include "device_info.h"

/*
 * #define's
 */

/* alias node searching return values */
#define	NO_MATCH	-1
#define	EXACT_MATCH	1
#define	INEXACT_MATCH	2

/* for prom io operations */
#define	BUFSIZE		4096
#define	MAXPROPSIZE	256
#define	MAXVALSIZE	(BUFSIZE - MAXPROPSIZE - sizeof (uint_t))

/* prom_obp_vers() return values */
#define	OBP_OF			0x4	/* versions OBP 3.x */
#define	OBP_NO_ALIAS_NODE	0x8	/* No alias node */

/* for nftw call */
#define	FT_DEPTH	15

/* default logical and physical device name space */
#define	DEV	"/dev"
#define	DEVICES	"/devices"

/* for boot device identification on x86 */
#define	CREATE_DISKMAP		"/boot/solaris/bin/create_diskmap"
#define	GRUBDISK_MAP		"/var/run/solaris_grubdisk.map"

/*
 * internal structure declarations
 */

/* for prom io functions */
typedef union {
	char buf[BUFSIZE];
	struct openpromio opp;
} Oppbuf;

/* used to manage lists of devices and aliases */
struct name_list {
	char *name;
	struct name_list *next;
};

/*
 * internal global data
 */

/* global since nftw does not let you pass args to be updated */
static struct name_list **dev_list;

/* global since nftw does not let you pass args to be updated */
static struct boot_dev **bootdev_list;

/* mutex to protect bootdev_list and dev_list */
static mutex_t dev_lists_lk = DEFAULTMUTEX;

/*
 * internal function prototypes
 */

static int prom_open(int);
static void prom_close(int);
static int is_openprom(int);

static int prom_dev_to_alias(char *dev, uint_t options, char ***ret_buf);
static int alias_to_prom_dev(char *alias, char *ret_buf);
static int prom_srch_aliases_by_def(char *, struct name_list **,
    struct name_list **, int);
static int prom_find_aliases_node(int fd);
static int prom_compare_devs(char *prom_dev1, char *prom_dev2);
static int _prom_strcmp(char *s1, char *s2);
static int prom_srch_node(int fd, char *prop_name, char *ret_buf);
static uint_t prom_next_node(int fd, uint_t node_id);
static uint_t prom_child_node(int fd, uint_t node_id);

static int prom_obp_vers(void);

static void parse_name(char *, char **, char **, char **);
static int process_bootdev(const char *, const char *, struct boot_dev ***);
static int process_minor_name(char *dev_path, const char *default_root);
static void options_override(char *prom_path, char *alias_name);
static int devfs_phys_to_logical(struct boot_dev **bootdev_array,
	const int array_size, const char *default_root);
static int check_logical_dev(const char *, const struct stat *, int,
	struct FTW *);
static struct boot_dev *alloc_bootdev(char *);
static void free_name_list(struct name_list *list, int free_name);
static int insert_alias_list(struct name_list **list,
	char *alias_name);
static int get_boot_dev_var(struct openpromio *opp);
static int set_boot_dev_var(struct openpromio *opp, char *bootdev);
static int devfs_prom_to_dev_name(char *prom_path, char *dev_path);
static int devfs_dev_to_prom_names(char *dev_path, char *prom_path, size_t len);

/*
 * frees a list of paths from devfs_get_prom_name_list
 */
static void
prom_list_free(char **prom_list)
{
	int i = 0;

	if (!prom_list)
		return;

	while (prom_list[i]) {
		free(prom_list[i]);
		i++;
	}
	free(prom_list);
}

static int
devfs_get_prom_name_list(const char *dev_name, char ***prom_list)
{
	char *prom_path = NULL;
	int count = 0;		/* # of slots we will need in prom_list */
	int ret, i, len;
	char **list;
	char *ptr;

	if (dev_name == NULL)
		return (DEVFS_INVAL);
	if (*dev_name != '/')
		return (DEVFS_INVAL);
	if (prom_list == NULL)
		return (DEVFS_INVAL);

	/*
	 * make sure we are on a machine which supports a prom
	 * and we have permission to use /dev/openprom
	 */
	if ((ret = prom_obp_vers()) < 0)
		return (ret);
	if ((prom_path = (char *)malloc(MAXVALSIZE)) == NULL)
		return (DEVFS_NOMEM);
	/*
	 * get the prom path name
	 */
	ret = devfs_dev_to_prom_names((char *)dev_name, prom_path, MAXVALSIZE);
	if (ret < 0) {
		free(prom_path);
		return (ret);
	}
	/* deal with list of names */
	for (i = 0; i < ret; i++)
		if (prom_path[i] == '\0')
			count++;

	if ((list = (char **)calloc(count + 1, sizeof (char *))) == NULL) {
		free(prom_path);
		return (DEVFS_NOMEM);
	}

	ptr = prom_path;
	for (i = 0; i < count; i++) {
		len = strlen(ptr) + 1;
		if ((list[i] = (char *)malloc(len)) == NULL) {
			free(prom_path);
			free(list);
			return (DEVFS_NOMEM);
		}
		(void) snprintf(list[i], len, "%s", ptr);
		ptr += len;
	}

	free(prom_path);

	*prom_list = list;
	return (0);
}

/*
 * retrieve the list of prom representations for a given device name
 * the list will be sorted in the following order: exact aliases,
 * inexact aliases, prom device path name.  If multiple matches occur
 * for exact or inexact aliases, then these are sorted in collating
 * order. The list is returned in prom_list
 *
 * the list may be restricted by specifying the correct flags in options.
 */
int
devfs_get_prom_names(const char *dev_name, uint_t options, char ***prom_list)
{
	char *prom_path = NULL;
	int count = 0;		/* # of slots we will need in prom_list */
	char **alias_list = NULL;
	char **list;
	int ret;

	if (dev_name == NULL) {
		return (DEVFS_INVAL);
	}
	if (*dev_name != '/') {
		return (DEVFS_INVAL);
	}
	if (prom_list == NULL) {
		return (DEVFS_INVAL);
	}
	/*
	 * make sure we are on a machine which supports a prom
	 * and we have permission to use /dev/openprom
	 */
	if ((ret = prom_obp_vers()) < 0) {
		return (ret);
	}
	if ((prom_path = (char *)malloc(MAXPATHLEN)) == NULL) {
		return (DEVFS_NOMEM);
	}
	/*
	 * get the prom path name
	 */
	ret = devfs_dev_to_prom_name((char *)dev_name, prom_path);
	if (ret < 0) {
		free(prom_path);
		return (ret);
	}
	/* get the list of aliases (exact and inexact) */
	if ((ret = prom_dev_to_alias(prom_path, options, &alias_list)) < 0) {
		free(prom_path);
		return (ret);
	}
	/* now figure out how big the return array must be */
	if (alias_list != NULL) {
		while (alias_list[count] != NULL) {
			count++;
		}
	}
	if ((options & BOOTDEV_NO_PROM_PATH) == 0) {
		count++;	/* # of slots we will need in prom_list */
	}
	count++;	/* for the null terminator */

	/* allocate space for the list */
	if ((list = (char **)calloc(count, sizeof (char *))) == NULL) {
		count = 0;
		while ((alias_list) && (alias_list[count] != NULL)) {
			free(alias_list[count]);
			count++;
		}
		free(alias_list);
		free(prom_path);
		return (DEVFS_NOMEM);
	}
	/* fill in the array and free the name list of aliases. */
	count = 0;
	while ((alias_list) && (alias_list[count] != NULL)) {
		list[count] = alias_list[count];
		count++;
	}
	if ((options & BOOTDEV_NO_PROM_PATH) == 0) {
		list[count] = prom_path;
	}
	if (alias_list != NULL) {
		free(alias_list);
	}
	*prom_list = list;
	return (0);
}

/*
 * Get a list prom-path translations for a solaris device.
 *
 * Returns the number of and all OBP paths and alias variants that
 * reference the Solaris device path passed in.
 */
int
devfs_get_all_prom_names(const char *solaris_path, uint_t flags,
    struct devfs_prom_path **paths)
{
	int ret, len, i, count = 0;
	char *ptr, *prom_path;
	struct devfs_prom_path *cur = NULL, *new;

	if ((ret = prom_obp_vers()) < 0)
		return (ret);
	if ((prom_path = (char *)malloc(MAXVALSIZE)) == NULL)
		return (DEVFS_NOMEM);

	if ((ret = devfs_dev_to_prom_names((char *)solaris_path,
	    prom_path, MAXVALSIZE)) < 0) {
		free(prom_path);
		return (ret);
	}

	for (i = 0; i < ret; i++)
		if (prom_path[i] == '\0')
			count++;

	*paths = NULL;
	ptr = prom_path;
	for (i = 0; i < count; i++) {
		if ((new = (struct devfs_prom_path *)calloc(
		    sizeof (struct devfs_prom_path), 1)) == NULL) {
			free(prom_path);
			devfs_free_all_prom_names(*paths);
			return (DEVFS_NOMEM);
		}

		if (cur == NULL)
			*paths = new;
		else
			cur->next = new;
		cur = new;

		len = strlen(ptr) + 1;
		if ((cur->obp_path = (char *)calloc(len, 1)) == NULL) {
			free(prom_path);
			devfs_free_all_prom_names(*paths);
			return (DEVFS_NOMEM);
		}

		(void) snprintf(cur->obp_path, len, "%s", ptr);
		ptr += len;
		if ((ret = prom_dev_to_alias(cur->obp_path, flags,
		    &(cur->alias_list))) < 0) {
			free(prom_path);
			devfs_free_all_prom_names(*paths);
			return (ret);
		}
	}

	free(prom_path);
	return (count);
}

void
devfs_free_all_prom_names(struct devfs_prom_path *paths)
{
	int i;

	if (paths == NULL)
		return;

	devfs_free_all_prom_names(paths->next);

	if (paths->obp_path != NULL)
		free(paths->obp_path);

	if (paths->alias_list != NULL) {
		for (i = 0; paths->alias_list[i] != NULL; i++)
			if (paths->alias_list[i] != NULL)
				free(paths->alias_list[i]);

		free(paths->alias_list);
	}

	free(paths);
}

/*
 * Accepts a device name as an input argument.  Uses this to set the
 * boot-device (or like) variable
 *
 * By default, this routine prepends to the list and converts the
 * logical device name to its most compact prom representation.
 * Available options include: converting the device name to a prom
 * path name (but not an alias) or performing no conversion at all;
 * overwriting the existing contents of boot-device rather than
 * prepending.
 */
int
devfs_bootdev_set_list(const char *dev_name, const uint_t options)
{
	char *prom_path;
	char *new_bootdev;
	char *ptr;
	char **alias_list = NULL;
	char **prom_list = NULL;
	Oppbuf  oppbuf;
	struct openpromio *opp = &(oppbuf.opp);
	int ret, len, i, j;

	if (devfs_bootdev_modifiable() != 0) {
		return (DEVFS_NOTSUP);
	}
	if (dev_name == NULL) {
		return (DEVFS_INVAL);
	}
	if (strlen(dev_name) >= MAXPATHLEN)
		return (DEVFS_INVAL);

	if ((*dev_name != '/') && !(options & BOOTDEV_LITERAL)) {
		return (DEVFS_INVAL);
	}
	if ((options & BOOTDEV_LITERAL) && (options & BOOTDEV_PROMDEV)) {
		return (DEVFS_INVAL);
	}
	/*
	 * if we are prepending, make sure that this obp rev
	 * supports multiple boot device entries.
	 */
	ret = prom_obp_vers();
	if (ret < 0) {
		return (ret);
	}

	if ((prom_path = (char *)malloc(MAXVALSIZE)) == NULL) {
		return (DEVFS_NOMEM);
	}
	if (options & BOOTDEV_LITERAL) {
		(void) strcpy(prom_path, dev_name);
	} else {
		/* need to convert to prom representation */
		ret = devfs_get_prom_name_list(dev_name, &prom_list);
		if (ret < 0) {
			free(prom_path);
			return (ret);
		}

		len = MAXVALSIZE;
		i = 0;
		ptr = prom_path;
		while (prom_list && prom_list[i]) {
			if (!(options & BOOTDEV_PROMDEV)) {
				ret = prom_dev_to_alias(prom_list[i], 0,
					&alias_list);
				if (ret < 0) {
					free(prom_path);
					prom_list_free(prom_list);
					return (ret);
				}
				if ((alias_list != NULL) &&
				    (alias_list[0] != NULL)) {
					(void) snprintf(ptr, len, "%s ",
					    alias_list[0]);
					for (ret = 0; alias_list[ret] != NULL;
					    ret++)
						free(alias_list[ret]);
				} else {
					(void) snprintf(ptr, len, "%s ",
					    prom_list[i]);
				}
				if (alias_list != NULL)
					free(alias_list);
			} else {
				(void) snprintf(ptr, len, "%s ", prom_list[i]);
			}
			j = strlen(ptr);
			len -= j;
			ptr += j;
			i++;
		}
		ptr--;
		*ptr = NULL;

		prom_list_free(prom_list);
	}
	if (options & BOOTDEV_OVERWRITE) {
		new_bootdev = prom_path;
	} else {
		/* retrieve the current value of boot-device */
		ret = get_boot_dev_var(opp);
		if (ret < 0) {
			free(prom_path);
			return (ret);
		}
		/* prepend new entry - deal with duplicates */
		new_bootdev = (char *)malloc(strlen(opp->oprom_array)
		    + strlen(prom_path) + 2);
		if (new_bootdev == NULL) {
			free(prom_path);
			return (DEVFS_NOMEM);
		}
		(void) strcpy(new_bootdev, prom_path);
		if (opp->oprom_size > 0) {
			for (ptr = strtok(opp->oprom_array, " "); ptr != NULL;
			    ptr = strtok(NULL, " ")) {
				/* we strip out duplicates */
				if (strcmp(prom_path, ptr) == 0) {
					continue;
				}
				(void) strcat(new_bootdev, " ");
				(void) strcat(new_bootdev, ptr);
			}
		}
	}

	/* now set the new value */
	ret = set_boot_dev_var(opp, new_bootdev);

	if (options & BOOTDEV_OVERWRITE) {
		free(prom_path);
	} else {
		free(new_bootdev);
		free(prom_path);
	}

	return (ret);
}

/*
 * sets the string bootdev as the new value for boot-device
 */
static int
set_boot_dev_var(struct openpromio *opp, char *bootdev)
{
	int prom_fd;
	int i;
	int ret;
	char *valbuf;
	char *save_bootdev;
	char *bootdev_variables[] = {
		"boot-device",
		"bootdev",
		"boot-from",
		NULL
	};
	int found = 0;
	int *ip = (int *)((void *)opp->oprom_array);

	/* query the prom */
	prom_fd = prom_open(O_RDWR);
	if (prom_fd < 0) {
		return (prom_fd);
	}

	/* get the diagnostic-mode? property */
	(void) strcpy(opp->oprom_array, "diagnostic-mode?");
	opp->oprom_size = MAXVALSIZE;
	if (ioctl(prom_fd, OPROMGETOPT, opp) >= 0) {
		if ((opp->oprom_size > 0) &&
		    (strcmp(opp->oprom_array, "true") == 0)) {
			prom_close(prom_fd);
			return (DEVFS_ERR);
		}
	}
	/* get the diag-switch? property */
	(void) strcpy(opp->oprom_array, "diag-switch?");
	opp->oprom_size = MAXVALSIZE;
	if (ioctl(prom_fd, OPROMGETOPT, opp) >= 0) {
		if ((opp->oprom_size > 0) &&
		    (strcmp(opp->oprom_array, "true") == 0)) {
			prom_close(prom_fd);
			return (DEVFS_ERR);
		}
	}
	/*
	 * look for one of the following properties in order:
	 *	boot-device
	 *	bootdev
	 *	boot-from
	 *
	 * Use the first one that we find.
	 */
	*ip = 0;
	opp->oprom_size = MAXPROPSIZE;
	while ((opp->oprom_size != 0) && (!found)) {
		opp->oprom_size = MAXPROPSIZE;
		if (ioctl(prom_fd, OPROMNXTOPT, opp) < 0) {
			break;
		}
		for (i = 0; bootdev_variables[i] != NULL; i++) {
			if (strcmp(opp->oprom_array, bootdev_variables[i])
			    == 0) {
				found = 1;
				break;
			}
		}
	}
	if (found) {
		(void) strcpy(opp->oprom_array, bootdev_variables[i]);
		opp->oprom_size = MAXVALSIZE;
		if (ioctl(prom_fd, OPROMGETOPT, opp) < 0) {
			prom_close(prom_fd);
			return (DEVFS_NOTSUP);
		}
	} else {
		prom_close(prom_fd);
		return (DEVFS_NOTSUP);
	}

	/* save the old copy in case we fail */
	if ((save_bootdev = strdup(opp->oprom_array)) == NULL) {
		prom_close(prom_fd);
		return (DEVFS_NOMEM);
	}
	/* set up the new value of boot-device */
	(void) strcpy(opp->oprom_array, bootdev_variables[i]);
	valbuf = opp->oprom_array + strlen(opp->oprom_array) + 1;
	(void) strcpy(valbuf, bootdev);

	opp->oprom_size = strlen(valbuf) + strlen(opp->oprom_array) + 2;

	if (ioctl(prom_fd, OPROMSETOPT, opp) < 0) {
		free(save_bootdev);
		prom_close(prom_fd);
		return (DEVFS_ERR);
	}

	/*
	 * now read it back to make sure it took
	 */
	(void) strcpy(opp->oprom_array, bootdev_variables[i]);
	opp->oprom_size = MAXVALSIZE;
	if (ioctl(prom_fd, OPROMGETOPT, opp) >= 0) {
		if (_prom_strcmp(opp->oprom_array, bootdev) == 0) {
			/* success */
			free(save_bootdev);
			prom_close(prom_fd);
			return (0);
		}
		/* deal with setting it to "" */
		if ((strlen(bootdev) == 0) && (opp->oprom_size == 0)) {
			/* success */
			free(save_bootdev);
			prom_close(prom_fd);
			return (0);
		}
	}
	/*
	 * something did not take - write out the old value and
	 * hope that we can restore things...
	 *
	 * unfortunately, there is no way for us to differentiate
	 * whether we exceeded the maximum number of characters
	 * allowable.  The limit varies from prom rev to prom
	 * rev, and on some proms, when the limit is
	 * exceeded, whatever was in the
	 * boot-device variable becomes unreadable.
	 *
	 * so if we fail, we will assume we ran out of room.  If we
	 * not able to restore the original setting, then we will
	 * return DEVFS_ERR instead.
	 */
	ret = DEVFS_LIMIT;
	(void) strcpy(opp->oprom_array, bootdev_variables[i]);
	valbuf = opp->oprom_array + strlen(opp->oprom_array) + 1;
	(void) strcpy(valbuf, save_bootdev);

	opp->oprom_size = strlen(valbuf) + strlen(opp->oprom_array) + 2;

	if (ioctl(prom_fd, OPROMSETOPT, opp) < 0) {
		ret = DEVFS_ERR;
	}
	free(save_bootdev);
	prom_close(prom_fd);
	return (ret);
}
/*
 * retrieve the current value for boot-device
 */
static int
get_boot_dev_var(struct openpromio *opp)
{
	int prom_fd;
	int i;
	char *bootdev_variables[] = {
		"boot-device",
		"bootdev",
		"boot-from",
		NULL
	};
	int found = 0;
	int *ip = (int *)((void *)opp->oprom_array);

	/* query the prom */
	prom_fd = prom_open(O_RDONLY);
	if (prom_fd < 0) {
		return (prom_fd);
	}

	/* get the diagnostic-mode? property */
	(void) strcpy(opp->oprom_array, "diagnostic-mode?");
	opp->oprom_size = MAXVALSIZE;
	if (ioctl(prom_fd, OPROMGETOPT, opp) >= 0) {
		if ((opp->oprom_size > 0) &&
		    (strcmp(opp->oprom_array, "true") == 0)) {
			prom_close(prom_fd);
			return (DEVFS_ERR);
		}
	}
	/* get the diag-switch? property */
	(void) strcpy(opp->oprom_array, "diag-switch?");
	opp->oprom_size = MAXVALSIZE;
	if (ioctl(prom_fd, OPROMGETOPT, opp) >= 0) {
		if ((opp->oprom_size > 0) &&
		    (strcmp(opp->oprom_array, "true") == 0)) {
			prom_close(prom_fd);
			return (DEVFS_ERR);
		}
	}
	/*
	 * look for one of the following properties in order:
	 *	boot-device
	 *	bootdev
	 *	boot-from
	 *
	 * Use the first one that we find.
	 */
	*ip = 0;
	opp->oprom_size = MAXPROPSIZE;
	while ((opp->oprom_size != 0) && (!found)) {
		opp->oprom_size = MAXPROPSIZE;
		if (ioctl(prom_fd, OPROMNXTOPT, opp) < 0) {
			break;
		}
		for (i = 0; bootdev_variables[i] != NULL; i++) {
			if (strcmp(opp->oprom_array, bootdev_variables[i])
			    == 0) {
				found = 1;
				break;
			}
		}
	}
	if (found) {
		(void) strcpy(opp->oprom_array, bootdev_variables[i]);
		opp->oprom_size = MAXVALSIZE;
		if (ioctl(prom_fd, OPROMGETOPT, opp) < 0) {
			prom_close(prom_fd);
			return (DEVFS_ERR);
		}
		/* boot-device exists but contains nothing */
		if (opp->oprom_size == 0) {
			*opp->oprom_array = '\0';
		}
	} else {
		prom_close(prom_fd);
		return (DEVFS_NOTSUP);
	}
	prom_close(prom_fd);
	return (0);
}

#ifndef __sparc
static FILE *
open_diskmap(void)
{
	FILE *fp;
	char cmd[PATH_MAX];

	/* make sure we have a map file */
	fp = fopen(GRUBDISK_MAP, "r");
	if (fp == NULL) {
		(void) snprintf(cmd, sizeof (cmd),
		    "%s > /dev/null", CREATE_DISKMAP);
		(void) system(cmd);
		fp = fopen(GRUBDISK_MAP, "r");
	}
	return (fp);
}

static int
find_x86_boot_device(struct openpromio *opp)
{
	int ret = DEVFS_ERR;
	char *cp, line[MAXVALSIZE + 6];
	FILE *file;

	file = open_diskmap();
	if (file == NULL)
		return (DEVFS_ERR);

	while (fgets(line, MAXVALSIZE + 6, file)) {
		if (strncmp(line, "0 ", 2) != 0)
			continue;
		/* drop new-line */
		line[strlen(line) - 1] = '\0';
		/*
		 * an x86 BIOS only boots a disk, not a partition
		 * or a slice, so hard-code :q (p0)
		 */
		cp = strchr(line + 2, ' ');
		if (cp == NULL)
			break;
		(void) snprintf(opp->oprom_array, MAXVALSIZE,
		    "%s:q", cp + 1);
		opp->oprom_size = MAXVALSIZE;
		ret = 0;
		break;
	}
	(void) fclose(file);
	return (ret);
}
#endif /* ndef __sparc */

/*
 * retrieve the list of entries in the boot-device configuration
 * variable.  An array of boot_dev structs will be created, one entry
 * for each device name in the boot-device variable.  Each entry
 * in the array will contain the logical device representation of the
 * boot-device entry, if any.
 *
 * default_root. if set, is used to locate logical device entries in
 * directories other than /dev
 */
int
devfs_bootdev_get_list(const char *default_root,
	struct boot_dev ***bootdev_list)
{
	Oppbuf  oppbuf;
	struct openpromio *opp = &(oppbuf.opp);
	int i;
	struct boot_dev **tmp_list;

	if (default_root == NULL) {
		default_root = "";
	} else if (*default_root != '/') {
		return (DEVFS_INVAL);
	}

	if (bootdev_list == NULL) {
		return (DEVFS_INVAL);
	}

	/* get the boot-device variable */
#if defined(sparc)
	i = get_boot_dev_var(opp);
#else
	i = find_x86_boot_device(opp);
#endif
	if (i < 0) {
		return (i);
	}
	/* now try to translate each entry to a logical device. */
	i = process_bootdev(opp->oprom_array, default_root, &tmp_list);
	if (i == 0) {
		*bootdev_list = tmp_list;
		return (0);
	} else {
		return (i);
	}
}

/*
 * loop thru the list of entries in a boot-device configuration
 * variable.
 */
static int
process_bootdev(const char *bootdevice, const char *default_root,
	struct boot_dev ***list)
{
	int i;
	char *entry, *ptr;
	char prom_path[MAXPATHLEN];
	char ret_buf[MAXPATHLEN];
	struct boot_dev **bootdev_array;
	int num_entries = 0;
	int found = 0;
	int vers;

	if ((entry = (char *)malloc(strlen(bootdevice) + 1)) == NULL) {
		return (DEVFS_NOMEM);
	}
	/* count the number of entries */
	(void) strcpy(entry, bootdevice);
	for (ptr = strtok(entry, " "); ptr != NULL;
	    ptr = strtok(NULL, " ")) {
		num_entries++;
	}
	(void) strcpy(entry, bootdevice);

	bootdev_array = (struct boot_dev **)
	    calloc((size_t)num_entries + 1, sizeof (struct boot_dev *));

	if (bootdev_array == NULL) {
		free(entry);
		return (DEVFS_NOMEM);
	}

	vers = prom_obp_vers();
	if (vers < 0) {
		free(entry);
		return (vers);
	}

	/* for each entry in boot-device, do... */
	for (ptr = strtok(entry, " "), i = 0; ptr != NULL;
	    ptr = strtok(NULL, " "), i++) {

		if ((bootdev_array[i] = alloc_bootdev(ptr)) == NULL) {
			devfs_bootdev_free_list(bootdev_array);
			free(entry);
			return (DEVFS_NOMEM);
		}

		/*
		 * prom boot-device may be aliased, so we need to do
		 * the necessary prom alias to dev translation.
		 */
		if (*ptr != '/') {
			if (alias_to_prom_dev(ptr, prom_path) < 0) {
				continue;
			}
		} else {
			(void) strcpy(prom_path, ptr);
		}

		/* now we have a prom device path - convert to a devfs name */
		if (devfs_prom_to_dev_name(prom_path, ret_buf) < 0) {
		    continue;
		}

		/* append any default minor names necessary */
		if (process_minor_name(ret_buf, default_root) < 0) {
		    continue;
		}
		found = 1;

		/*
		 * store the physical device path for now - when
		 * we are all done with the entries, we will convert
		 * these to their logical device name equivalents
		 */
		bootdev_array[i]->bootdev_trans[0] = strdup(ret_buf);
	}
	/*
	 * Convert all of the boot-device entries that translated to a
	 * physical device path in /devices to a logical device path
	 * in /dev (note that there may be several logical device paths
	 * associated with a single physical device path - return them all
	 */
	if (found) {
		if (devfs_phys_to_logical(bootdev_array, num_entries,
		    default_root) < 0) {
			devfs_bootdev_free_list(bootdev_array);
			bootdev_array = NULL;
		}
	}
	free(entry);
	*list = bootdev_array;
	return (0);
}

/*
 * We may get a device path from the prom that has no minor name
 * information included in it.  Since this device name will not
 * correspond directly to a physical device in /devices, we do our
 * best to append what the default minor name should be and try this.
 *
 * For sparc: we append slice 0 (:a).
 * For x86: we append fdisk partition 0 (:q).
 */
static int
process_minor_name(char *dev_path, const char *root)
{
	char *cp;
#if defined(sparc)
	const char *default_minor_name = "a";
#else
	const char *default_minor_name = "q";
#endif
	int n;
	struct stat stat_buf;
	char path[MAXPATHLEN];

	(void) snprintf(path, sizeof (path), "%s%s%s", root, DEVICES, dev_path);
	/*
	 * if the device file already exists as given to us, there
	 * is nothing to do but return.
	 */
	if (stat(path, &stat_buf) == 0) {
		return (0);
	}
	/*
	 * if there is no ':' after the last '/' character, or if there is
	 * a ':' with no specifier, append the default segment specifier
	 * ; if there is a ':' followed by a digit, this indicates
	 * a partition number (which does not map into the /devices name
	 * space), so strip the number and replace it with the letter
	 * that represents the partition index
	 */
	if ((cp = strrchr(dev_path, '/')) != NULL) {
		if ((cp = strchr(cp, ':')) == NULL) {
			(void) strcat(dev_path, ":");
			(void) strcat(dev_path, default_minor_name);
		} else if (*++cp == '\0') {
			(void) strcat(dev_path, default_minor_name);
		} else if (isdigit(*cp)) {
			n = atoi(cp);
			/* make sure to squash the digit */
			*cp = '\0';
			switch (n) {
			    case 0:	(void) strcat(dev_path, "q");
					break;
			    case 1:	(void) strcat(dev_path, "r");
					break;
			    case 2:	(void) strcat(dev_path, "s");
					break;
			    case 3:	(void) strcat(dev_path, "t");
					break;
			    case 4:	(void) strcat(dev_path, "u");
					break;
			    default:	(void) strcat(dev_path, "a");
					break;
			}
		}
	}
	/*
	 * see if we can find something now.
	 */
	(void) snprintf(path, sizeof (path), "%s%s%s", root, DEVICES, dev_path);

	if (stat(path, &stat_buf) == 0) {
		return (0);
	} else {
		return (-1);
	}
}

/*
 * for each entry in bootdev_array, convert the physical device
 * representation of the boot-device entry to one or more logical device
 * entries.  We use the hammer method - walk through the logical device
 * name space looking for matches (/dev).  We use nftw to do this.
 */
static int
devfs_phys_to_logical(struct boot_dev **bootdev_array, const int array_size,
    const char *default_root)
{
	int walk_flags = FTW_PHYS | FTW_MOUNT;
	char *full_path;
	struct name_list *list;
	int count, i;
	char **dev_name_array;
	size_t default_root_len;
	char *dev_dir = DEV;
	int len;

	if (array_size < 0) {
		return (-1);
	}

	if (bootdev_array == NULL) {
		return (-1);
	}
	if (default_root == NULL) {
		return (-1);
	}
	default_root_len = strlen(default_root);
	if ((default_root_len != 0) && (*default_root != '/')) {
		return (-1);
	}

	/* short cut for an empty array */
	if (*bootdev_array == NULL) {
		return (0);
	}

	/* tell nftw where to start (default: /dev) */
	len = default_root_len + strlen(dev_dir) + 1;
	if ((full_path = (char *)malloc(len)) == NULL) {
		return (-1);
	}

	/*
	 * if the default root path is terminated with a /, we have to
	 * make sure we don't end up with one too many slashes in the
	 * path we are building.
	 */
	if ((default_root_len > (size_t)0) &&
	    (default_root[default_root_len - 1] == '/')) {
		(void) snprintf(full_path, len, "%s%s", default_root,
		    &dev_dir[1]);
	} else {
		(void) snprintf(full_path, len, "%s%s", default_root, dev_dir);
	}

	/*
	 * we need to muck with global data to make nftw work
	 * so single thread access
	 */
	(void) mutex_lock(&dev_lists_lk);

	/*
	 * set the global vars bootdev_list and dev_list for use by nftw
	 * dev_list is an array of lists - one for each boot-device
	 * entry.  The nftw function will create a list of logical device
	 * entries for each boot-device and put all of the lists in
	 * dev_list.
	 */
	dev_list = (struct name_list **)
	    calloc(array_size, sizeof (struct name_list *));
	if (dev_list == NULL) {
		free(full_path);
		(void) mutex_unlock(&dev_lists_lk);
		return (-1);
	}
	bootdev_list = bootdev_array;

	if (nftw(full_path, check_logical_dev, FT_DEPTH, walk_flags) == -1) {
		bootdev_list = NULL;
		free(full_path);
		for (i = 0; i < array_size; i++) {
			free_name_list(dev_list[i], 1);
		}
		/* don't free dev_list here because it's been handed off */
		dev_list = NULL;
		(void) mutex_unlock(&dev_lists_lk);
		return (-1);
	}

	/*
	 * now we