diff options
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/md.c | 36 |
1 files changed, 30 insertions, 6 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 5022be183390..554bf213c043 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -5162,6 +5162,15 @@ static void no_op(struct percpu_ref *r) {} static int md_alloc(dev_t dev, char *name) { + /* + * If dev is zero, name is the name of a device to allocate with + * an arbitrary minor number. It will be "md_???" + * If dev is non-zero it must be a device number with a MAJOR of + * MD_MAJOR or mdp_major. In this case, if "name" is NULL, then + * the device is being created by opening a node in /dev. + * If "name" is not NULL, the device is being created by + * writing to /sys/module/md_mod/parameters/new_array. + */ static DEFINE_MUTEX(disks_mutex); struct mddev *mddev = mddev_find(dev); struct gendisk *disk; @@ -5187,7 +5196,7 @@ static int md_alloc(dev_t dev, char *name) if (mddev->gendisk) goto abort; - if (name) { + if (name && !dev) { /* Need to ensure that 'name' is not a duplicate. */ struct mddev *mddev2; @@ -5201,6 +5210,11 @@ static int md_alloc(dev_t dev, char *name) } spin_unlock(&all_mddevs_lock); } + if (name && dev) + /* + * Creating /dev/mdNNN via "newarray", so adjust hold_active. + */ + mddev->hold_active = UNTIL_STOP; error = -ENOMEM; mddev->queue = blk_alloc_queue(GFP_KERNEL); @@ -5277,21 +5291,31 @@ static struct kobject *md_probe(dev_t dev, int *part, void *data) static int add_named_array(const char *val, struct kernel_param *kp) { - /* val must be "md_*" where * is not all digits. - * We allocate an array with a large free minor number, and + /* + * val must be "md_*" or "mdNNN". + * For "md_*" we allocate an array with a large free minor number, and * set the name to val. val must not already be an active name. + * For "mdNNN" we allocate an array with the minor number NNN + * which must not already be in use. */ int len = strlen(val); char buf[DISK_NAME_LEN]; + unsigned long devnum; while (len && val[len-1] == '\n') len--; if (len >= DISK_NAME_LEN) return -E2BIG; strlcpy(buf, val, len+1); - if (strncmp(buf, "md_", 3) != 0) - return -EINVAL; - return md_alloc(0, buf); + if (strncmp(buf, "md_", 3) == 0) + return md_alloc(0, buf); + if (strncmp(buf, "md", 2) == 0 && + isdigit(buf[2]) && + kstrtoul(buf+2, 10, &devnum) == 0 && + devnum <= MINORMASK) + return md_alloc(MKDEV(MD_MAJOR, devnum), NULL); + + return -EINVAL; } static void md_safemode_timeout(unsigned long data) |