int fd_is_raid (int fd)
{
struct stat st;
if (!md_major())
return 0; /* not a RAID device */
if (fstat(fd, &st)) {
perror("fstat()");
return 0; /* ugh.. shouldn't happen */
}
return (major(st.st_rdev) == md_major());
}
/*
* "md" (RAID) devices have per-member "start" offsets.
* Realistically, we can only support raid1 arrays here,
* and only then when all members have the same "start" offsets.
*/
static int get_raid1_start_lba (int fd, __u64 *start_lba)
{
char buf[32];
unsigned int member, raid_disks;
__u64 start = 0, offset = 0;
if (sysfs_get_attr(fd, "md/level", "%s", buf, NULL, 0)
|| sysfs_get_attr(fd, "md/raid_disks", "%u", &raid_disks, NULL, 0))
return ENODEV;
if (strcmp(buf, "raid1") || !raid_disks)
return EINVAL;
for (member = 0; member < raid_disks; ++member) {
__u64 member_start, member_offset;
char member_path[32];
sprintf(member_path, "md/rd%u/offset", member);
if (sysfs_get_attr(fd, member_path, "%llu", &member_offset, NULL, 0))
member_offset = 0;
sprintf(member_path, "md/rd%u/block/dev", member);
if (sysfs_get_attr(fd, member_path, "%s", buf, NULL, 0))
return EINVAL;
if (md_major() == (unsigned)atoi(buf)) /* disallow recursive RAIDs */
return EINVAL;
sprintf(member_path, "md/rd%u/block/start", member);
if (sysfs_get_attr(fd, member_path, "%llu", &member_start, NULL, 0))
return ENODEV;
if (member == 0) {
start = member_start;
offset = member_offset;
} else if (member_start != start || member_offset != offset)
return EINVAL;
/* FIXME? Should --fibmap should account for member_offset in calculations? */
}
*start_lba = start;
return 0;
}
static int _is_partitionable(struct device *dev)
{
int parts = max_partitions(MAJOR(dev->dev));
/* All MD devices are partitionable via blkext (as of 2.6.28) */
if (MAJOR(dev->dev) == md_major())
return 1;
if ((parts <= 1) || (MINOR(dev->dev) % parts))
return 0;
return 1;
}
static int _md_sysfs_attribute_snprintf(char *path, size_t size,
const char *sysfs_dir,
struct device *blkdev,
const char *attribute)
{
struct stat info;
dev_t dev = blkdev->dev;
int ret = -1;
if (!sysfs_dir || !*sysfs_dir)
return ret;
if (MAJOR(dev) == blkext_major()) {
/* lookup parent MD device from blkext partition */
if (!get_primary_dev(sysfs_dir, blkdev, &dev))
return ret;
}
if (MAJOR(dev) != md_major())
return ret;
ret = dm_snprintf(path, size, "%s/dev/block/%d:%d/md/%s", sysfs_dir,
(int)MAJOR(dev), (int)MINOR(dev), attribute);
if (ret < 0) {
log_error("dm_snprintf md %s failed", attribute);
return ret;
}
if (stat(path, &info) == -1) {
if (errno != ENOENT) {
log_sys_error("stat", path);
return ret;
}
/* old sysfs structure */
ret = dm_snprintf(path, size, "%s/block/md%d/md/%s",
sysfs_dir, (int)MINOR(dev), attribute);
if (ret < 0) {
log_error("dm_snprintf old md %s failed", attribute);
return ret;
}
}
return ret;
}
