diff --git a/drivers/block/brd.c b/drivers/block/brd.c index a8a77a1efe1e..b2c109f08808 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -368,8 +368,40 @@ __setup("ramdisk_size=", ramdisk_size); * (should share code eventually). */ static LIST_HEAD(brd_devices); +static DEFINE_MUTEX(brd_devices_mutex); static struct dentry *brd_debugfs_dir; +static struct brd_device *brd_find_or_alloc_device(int i) +{ + struct brd_device *brd; + + mutex_lock(&brd_devices_mutex); + list_for_each_entry(brd, &brd_devices, brd_list) { + if (brd->brd_number == i) { + mutex_unlock(&brd_devices_mutex); + return ERR_PTR(-EEXIST); + } + } + + brd = kzalloc(sizeof(*brd), GFP_KERNEL); + if (!brd) { + mutex_unlock(&brd_devices_mutex); + return ERR_PTR(-ENOMEM); + } + brd->brd_number = i; + list_add_tail(&brd->brd_list, &brd_devices); + mutex_unlock(&brd_devices_mutex); + return brd; +} + +static void brd_free_device(struct brd_device *brd) +{ + mutex_lock(&brd_devices_mutex); + list_del(&brd->brd_list); + mutex_unlock(&brd_devices_mutex); + kfree(brd); +} + static int brd_alloc(int i) { struct brd_device *brd; @@ -377,14 +409,9 @@ static int brd_alloc(int i) char buf[DISK_NAME_LEN]; int err = -ENOMEM; - list_for_each_entry(brd, &brd_devices, brd_list) - if (brd->brd_number == i) - return -EEXIST; - brd = kzalloc(sizeof(*brd), GFP_KERNEL); - if (!brd) - return -ENOMEM; - brd->brd_number = i; - list_add_tail(&brd->brd_list, &brd_devices); + brd = brd_find_or_alloc_device(i); + if (IS_ERR(brd)) + return PTR_ERR(brd); spin_lock_init(&brd->brd_lock); INIT_RADIX_TREE(&brd->brd_pages, GFP_ATOMIC); @@ -428,8 +455,7 @@ static int brd_alloc(int i) out_cleanup_disk: put_disk(disk); out_free_dev: - list_del(&brd->brd_list); - kfree(brd); + brd_free_device(brd); return err; } @@ -448,8 +474,7 @@ static void brd_cleanup(void) del_gendisk(brd->brd_disk); put_disk(brd->brd_disk); brd_free_pages(brd); - list_del(&brd->brd_list); - kfree(brd); + brd_free_device(brd); } } @@ -476,16 +501,6 @@ static int __init brd_init(void) { int err, i; - brd_check_and_reset_par(); - - brd_debugfs_dir = debugfs_create_dir("ramdisk_pages", NULL); - - for (i = 0; i < rd_nr; i++) { - err = brd_alloc(i); - if (err) - goto out_free; - } - /* * brd module now has a feature to instantiate underlying device * structure on-demand, provided that there is an access dev node. @@ -501,11 +516,18 @@ static int __init brd_init(void) * dynamically. */ + brd_check_and_reset_par(); + + brd_debugfs_dir = debugfs_create_dir("ramdisk_pages", NULL); + if (__register_blkdev(RAMDISK_MAJOR, "ramdisk", brd_probe)) { err = -EIO; goto out_free; } + for (i = 0; i < rd_nr; i++) + brd_alloc(i); + pr_info("brd: module loaded\n"); return 0;