diff options
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/md.c | 119 |
1 files changed, 101 insertions, 18 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 38697283aaf4..f5cbb9d2371a 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -249,17 +249,51 @@ static mddev_t * mddev_find(dev_t unit) retry: spin_lock(&all_mddevs_lock); - list_for_each_entry(mddev, &all_mddevs, all_mddevs) - if (mddev->unit == unit) { - mddev_get(mddev); + + if (unit) { + list_for_each_entry(mddev, &all_mddevs, all_mddevs) + if (mddev->unit == unit) { + mddev_get(mddev); + spin_unlock(&all_mddevs_lock); + kfree(new); + return mddev; + } + + if (new) { + list_add(&new->all_mddevs, &all_mddevs); spin_unlock(&all_mddevs_lock); - kfree(new); - return mddev; + new->hold_active = UNTIL_IOCTL; + return new; } - - if (new) { + } else if (new) { + /* find an unused unit number */ + static int next_minor = 512; + int start = next_minor; + int is_free = 0; + int dev = 0; + while (!is_free) { + dev = MKDEV(MD_MAJOR, next_minor); + next_minor++; + if (next_minor > MINORMASK) + next_minor = 0; + if (next_minor == start) { + /* Oh dear, all in use. */ + spin_unlock(&all_mddevs_lock); + kfree(new); + return NULL; + } + + is_free = 1; + list_for_each_entry(mddev, &all_mddevs, all_mddevs) + if (mddev->unit == dev) { + is_free = 0; + break; + } + } + new->unit = dev; + new->md_minor = MINOR(dev); + new->hold_active = UNTIL_STOP; list_add(&new->all_mddevs, &all_mddevs); - mddev->hold_active = UNTIL_IOCTL; spin_unlock(&all_mddevs_lock); return new; } @@ -3491,18 +3525,22 @@ static struct kobj_type md_ktype = { int mdp_major = 0; -static struct kobject *md_probe(dev_t dev, int *part, void *data) +static int md_alloc(dev_t dev, char *name) { static DEFINE_MUTEX(disks_mutex); mddev_t *mddev = mddev_find(dev); struct gendisk *disk; - int partitioned = (MAJOR(dev) != MD_MAJOR); - int shift = partitioned ? MdpMinorShift : 0; - int unit = MINOR(dev) >> shift; + int partitioned; + int shift; + int unit; int error; if (!mddev) - return NULL; + return -ENODEV; + + partitioned = (MAJOR(mddev->unit) != MD_MAJOR); + shift = partitioned ? MdpMinorShift : 0; + unit = MINOR(mddev->unit) >> shift; /* wait for any previous instance if this device * to be completed removed (mddev_delayed_delete). @@ -3513,14 +3551,29 @@ static struct kobject *md_probe(dev_t dev, int *part, void *data) if (mddev->gendisk) { mutex_unlock(&disks_mutex); mddev_put(mddev); - return NULL; + return -EEXIST; + } + + if (name) { + /* Need to ensure that 'name' is not a duplicate. + */ + mddev_t *mddev2; + spin_lock(&all_mddevs_lock); + + list_for_each_entry(mddev2, &all_mddevs, all_mddevs) + if (mddev2->gendisk && + strcmp(mddev2->gendisk->disk_name, name) == 0) { + spin_unlock(&all_mddevs_lock); + return -EEXIST; + } + spin_unlock(&all_mddevs_lock); } mddev->queue = blk_alloc_queue(GFP_KERNEL); if (!mddev->queue) { mutex_unlock(&disks_mutex); mddev_put(mddev); - return NULL; + return -ENOMEM; } /* Can be unlocked because the queue is new: no concurrency */ queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, mddev->queue); @@ -3533,11 +3586,13 @@ static struct kobject *md_probe(dev_t dev, int *part, void *data) blk_cleanup_queue(mddev->queue); mddev->queue = NULL; mddev_put(mddev); - return NULL; + return -ENOMEM; } - disk->major = MAJOR(dev); + disk->major = MAJOR(mddev->unit); disk->first_minor = unit << shift; - if (partitioned) + if (name) + strcpy(disk->disk_name, name); + else if (partitioned) sprintf(disk->disk_name, "md_d%d", unit); else sprintf(disk->disk_name, "md%d", unit); @@ -3562,9 +3617,34 @@ static struct kobject *md_probe(dev_t dev, int *part, void *data) mddev->sysfs_state = sysfs_get_dirent(mddev->kobj.sd, "array_state"); } mddev_put(mddev); + return 0; +} + +static struct kobject *md_probe(dev_t dev, int *part, void *data) +{ + md_alloc(dev, NULL); return NULL; } +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 + * set the name to val. val must not already be an active name. + */ + int len = strlen(val); + char buf[DISK_NAME_LEN]; + + 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); +} + static void md_safemode_timeout(unsigned long data) { mddev_t *mddev = (mddev_t *) data; @@ -4025,6 +4105,8 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open) mddev->barriers_work = 0; mddev->safemode = 0; kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE); + if (mddev->hold_active == UNTIL_STOP) + mddev->hold_active = 0; } else if (mddev->pers) printk(KERN_INFO "md: %s switched to read-only mode.\n", @@ -6502,6 +6584,7 @@ static int set_ro(const char *val, struct kernel_param *kp) module_param_call(start_ro, set_ro, get_ro, NULL, S_IRUSR|S_IWUSR); module_param(start_dirty_degraded, int, S_IRUGO|S_IWUSR); +module_param_call(new_array, add_named_array, NULL, NULL, S_IWUSR); EXPORT_SYMBOL(register_md_personality); EXPORT_SYMBOL(unregister_md_personality); |