freebsd-nq/lib/libgeom/geom_util.c
Ulf Lilleengen f805f204b6 - Add a new ioctl for getting the provider name of a geom provider.
- Add a routine for looking up a device and checking if it is a valid geom
  provider given a partial or full path to its device node.

Reviewed by:	phk
Approved by:	pjd (mentor)
2008-09-07 13:54:57 +00:00

317 lines
6.2 KiB
C

/*-
* Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* 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 AUTHORS 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 AUTHORS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/disk.h>
#include <sys/stat.h>
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <paths.h>
#include <libgeom.h>
static char *g_device_path_open(const char *, int *, int);
/*
* Open the given provider and at least check if this is a block device.
*/
int
g_open(const char *name, int dowrite)
{
char *path;
int fd;
path = g_device_path_open(name, &fd, dowrite);
if (path != NULL)
free(path);
if (fd == -1)
return (-1);
return (fd);
}
int
g_close(int fd)
{
return (close(fd));
}
static int
g_ioctl_arg(int fd, unsigned long cmd, void *arg)
{
int ret;
if (arg != NULL)
ret = ioctl(fd, cmd, arg);
else
ret = ioctl(fd, cmd);
return (ret >= 0 ? 0 : -1);
}
static int
g_ioctl(int fd, unsigned long cmd)
{
return (g_ioctl_arg(fd, cmd, NULL));
}
/*
* Return media size of the given provider.
*/
off_t
g_mediasize(int fd)
{
off_t mediasize;
if (g_ioctl_arg(fd, DIOCGMEDIASIZE, &mediasize) == -1)
mediasize = -1;
return (mediasize);
}
/*
* Return sector size of the given provider.
*/
ssize_t
g_sectorsize(int fd)
{
u_int sectorsize;
if (g_ioctl_arg(fd, DIOCGSECTORSIZE, &sectorsize) == -1)
return (-1);
return ((ssize_t)sectorsize);
}
/*
* Return the correct provider name.
*/
char *
g_providername(int fd)
{
char name[MAXPATHLEN];
if (g_ioctl_arg(fd, DIOCGPROVIDERNAME, name) == -1)
return (NULL);
return (strdup(name));
}
/*
* Call BIO_FLUSH for the given provider.
*/
int
g_flush(int fd)
{
return (g_ioctl(fd, DIOCGFLUSH));
}
/*
* Call BIO_DELETE for the given range.
*/
int
g_delete(int fd, off_t offset, off_t length)
{
off_t arg[2];
arg[0] = offset;
arg[1] = length;
return (g_ioctl_arg(fd, DIOCGDELETE, arg));
}
/*
* Return ID of the given provider.
*/
int
g_get_ident(int fd, char *ident, size_t size)
{
char lident[DISK_IDENT_SIZE];
if (g_ioctl_arg(fd, DIOCGIDENT, lident) == -1)
return (-1);
if (lident[0] == '\0') {
errno = ENOENT;
return (-1);
}
if (strlcpy(ident, lident, size) >= size) {
errno = ENAMETOOLONG;
return (-1);
}
return (0);
}
/*
* Return name of the provider, which has the given ID.
*/
int
g_get_name(const char *ident, char *name, size_t size)
{
int fd;
fd = g_open_by_ident(ident, 0, name, size);
if (fd == -1)
return (-1);
g_close(fd);
return (0);
}
/*
* Find provider name by the given ID.
*/
int
g_open_by_ident(const char *ident, int dowrite, char *name, size_t size)
{
char lident[DISK_IDENT_SIZE];
struct gmesh mesh;
struct gclass *mp;
struct ggeom *gp;
struct gprovider *pp;
int error, fd;
error = geom_gettree(&mesh);
if (error != 0) {
errno = error;
return (-1);
}
error = ENOENT;
fd = -1;
LIST_FOREACH(mp, &mesh.lg_class, lg_class) {
LIST_FOREACH(gp, &mp->lg_geom, lg_geom) {
LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
fd = g_open(pp->lg_name, dowrite);
if (fd == -1)
continue;
if (g_get_ident(fd, lident,
sizeof(lident)) == -1) {
g_close(fd);
continue;
}
if (strcmp(ident, lident) != 0) {
g_close(fd);
continue;
}
error = 0;
if (name != NULL && strlcpy(name, pp->lg_name,
size) >= size) {
error = ENAMETOOLONG;
g_close(fd);
}
goto end;
}
}
}
end:
geom_deletetree(&mesh);
if (error != 0) {
errno = error;
return (-1);
}
return (fd);
}
/*
* Return the device path device given a partial or full path to its node.
* A pointer can be provided, which will be set to an opened file descriptor of
* not NULL.
*/
static char *
g_device_path_open(const char *devpath, int *fdp, int dowrite)
{
char *path;
int fd;
/* Make sure that we can fail. */
if (fdp != NULL)
*fdp = -1;
/* Use the device node if we're able to open it. */
do {
fd = open(devpath, dowrite ? O_RDWR : O_RDONLY);
if (fd == -1)
break;
/*
* Let try to get sectorsize, which will prove it is a GEOM
* provider.
*/
if (g_sectorsize(fd) == -1) {
close(fd);
errno = EFTYPE;
return (NULL);
}
if ((path = strdup(devpath)) == NULL) {
close(fd);
return (NULL);
}
if (fdp != NULL)
*fdp = fd;
else
close(fd);
return (path);
} while (0);
/* If we're not given an absolute path, assume /dev/ prefix. */
if (*devpath != '/') {
asprintf(&path, "%s%s", _PATH_DEV, devpath);
if (path == NULL)
return (NULL);
fd = open(path, dowrite ? O_RDWR : O_RDONLY);
if (fd == -1) {
free(path);
return (NULL);
}
/*
* Let try to get sectorsize, which will prove it is a GEOM
* provider.
*/
if (g_sectorsize(fd) == -1) {
free(path);
close(fd);
errno = EFTYPE;
return (NULL);
}
if (fdp != NULL)
*fdp = fd;
else
close(fd);
return (path);
}
return (NULL);
}
char *
g_device_path(const char *devpath)
{
return (g_device_path_open(devpath, NULL, 0));
}