/*
* Returns 1 if the device is private LVM device.
*/
int sysfs_devno_is_lvm_private(dev_t devno)
{
struct sysfs_cxt cxt = UL_SYSFSCXT_EMPTY;
char *uuid = NULL;
int rc = 0;
if (sysfs_init(&cxt, devno, NULL) != 0)
return 0;
uuid = sysfs_strdup(&cxt, "dm/uuid");
/* Private LVM devices use "LVM-<uuid>-<name>" uuid format (important
* is the "LVM" prefix and "-<name>" postfix).
*/
if (uuid && strncmp(uuid, "LVM-", 4) == 0) {
char *p = strrchr(uuid + 4, '-');
if (p && *(p + 1))
rc = 1;
}
sysfs_deinit(&cxt);
free(uuid);
return rc;
}
/*
* @lc: context
*
* Returns (allocated) string with path to the file assicieted
* with the current loop device.
*/
char *loopcxt_get_backing_file(struct loopdev_cxt *lc)
{
struct sysfs_cxt *sysfs = loopcxt_get_sysfs(lc);
char *res = NULL;
if (sysfs)
/*
* This is always preffered, the loop_info64
* has too small buffer for the filename.
*/
res = sysfs_strdup(sysfs, "loop/backing_file");
if (!res && loopcxt_ioctl_enabled(lc)) {
struct loop_info64 *lo = loopcxt_get_info(lc);
if (lo) {
lo->lo_file_name[LO_NAME_SIZE - 2] = '*';
lo->lo_file_name[LO_NAME_SIZE - 1] = '\0';
res = strdup((char *) lo->lo_file_name);
}
}
DBG(lc, loopdev_debug("get_backing_file [%s]", res));
return res;
}
/*
* Returns by @diskdevno whole disk device devno and (optionaly) by
* @diskname the whole disk device name.
*/
int sysfs_devno_to_wholedisk(dev_t dev, char *diskname,
size_t len, dev_t *diskdevno)
{
struct sysfs_cxt cxt;
int is_part = 0;
if (!dev || sysfs_init(&cxt, dev, NULL) != 0)
return -1;
is_part = sysfs_has_attribute(&cxt, "partition");
if (!is_part) {
/*
* Extra case for partitions mapped by device-mapper.
*
* All regualar partitions (added by BLKPG ioctl or kernel PT
* parser) have the /sys/.../partition file. The partitions
* mapped by DM don't have such file, but they have "part"
* prefix in DM UUID.
*/
char *uuid = sysfs_strdup(&cxt, "dm/uuid");
char *tmp = uuid;
char *prefix = uuid ? strsep(&tmp, "-") : NULL;
if (prefix && strncasecmp(prefix, "part", 4) == 0)
is_part = 1;
free(uuid);
if (is_part &&
get_dm_wholedisk(&cxt, diskname, len, diskdevno) == 0)
/*
* partitioned device, mapped by DM
*/
goto done;
is_part = 0;
}
if (!is_part) {
/*
* unpartitioned device
*/
if (diskname && len) {
if (!sysfs_get_devname(&cxt, diskname, len))
goto err;
}
if (diskdevno)
*diskdevno = dev;
} else {
/*
* partitioned device
* - readlink /sys/dev/block/8:1 = ../../block/sda/sda1
* - dirname ../../block/sda/sda1 = ../../block/sda
* - basename ../../block/sda = sda
*/
char linkpath[PATH_MAX];
char *name;
int linklen;
linklen = sysfs_readlink(&cxt, NULL,
linkpath, sizeof(linkpath) - 1);
if (linklen < 0)
goto err;
linkpath[linklen] = '\0';
stripoff_last_component(linkpath); /* dirname */
name = stripoff_last_component(linkpath); /* basename */
if (!name)
goto err;
if (diskname && len) {
strncpy(diskname, name, len);
diskname[len - 1] = '\0';
}
if (diskdevno) {
*diskdevno = sysfs_devname_to_devno(name, NULL);
if (!*diskdevno)
goto err;
}
}
done:
sysfs_deinit(&cxt);
return 0;
err:
sysfs_deinit(&cxt);
return -1;
}