12b2af54aSKay Sievers /* 22b2af54aSKay Sievers * devtmpfs - kernel-maintained tmpfs-based /dev 32b2af54aSKay Sievers * 42b2af54aSKay Sievers * Copyright (C) 2009, Kay Sievers <kay.sievers@vrfy.org> 52b2af54aSKay Sievers * 62b2af54aSKay Sievers * During bootup, before any driver core device is registered, 72b2af54aSKay Sievers * devtmpfs, a tmpfs-based filesystem is created. Every driver-core 82b2af54aSKay Sievers * device which requests a device node, will add a node in this 9e454cea2SKay Sievers * filesystem. 1002fbe5e6SPeter Korsgaard * By default, all devices are named after the name of the device, 1102fbe5e6SPeter Korsgaard * owned by root and have a default mode of 0600. Subsystems can 1202fbe5e6SPeter Korsgaard * overwrite the default setting if needed. 132b2af54aSKay Sievers */ 142b2af54aSKay Sievers 152b2af54aSKay Sievers #include <linux/kernel.h> 162b2af54aSKay Sievers #include <linux/syscalls.h> 172b2af54aSKay Sievers #include <linux/mount.h> 182b2af54aSKay Sievers #include <linux/device.h> 192b2af54aSKay Sievers #include <linux/genhd.h> 202b2af54aSKay Sievers #include <linux/namei.h> 212b2af54aSKay Sievers #include <linux/fs.h> 222b2af54aSKay Sievers #include <linux/shmem_fs.h> 23da5e4ef7SPeter Korsgaard #include <linux/ramfs.h> 24e454cea2SKay Sievers #include <linux/sched.h> 255a0e3ad6STejun Heo #include <linux/slab.h> 262780f1ffSAl Viro #include <linux/kthread.h> 272b2af54aSKay Sievers 282780f1ffSAl Viro static struct task_struct *thread; 292b2af54aSKay Sievers 302b2af54aSKay Sievers #if defined CONFIG_DEVTMPFS_MOUNT 31fc14f2feSAl Viro static int mount_dev = 1; 322b2af54aSKay Sievers #else 33fc14f2feSAl Viro static int mount_dev; 342b2af54aSKay Sievers #endif 352b2af54aSKay Sievers 362780f1ffSAl Viro static DEFINE_SPINLOCK(req_lock); 372780f1ffSAl Viro 382780f1ffSAl Viro static struct req { 392780f1ffSAl Viro struct req *next; 402780f1ffSAl Viro struct completion done; 412780f1ffSAl Viro int err; 422780f1ffSAl Viro const char *name; 432c9ede55SAl Viro umode_t mode; /* 0 => delete */ 442780f1ffSAl Viro struct device *dev; 452780f1ffSAl Viro } *requests; 46ed413ae6SKay Sievers 472b2af54aSKay Sievers static int __init mount_param(char *str) 482b2af54aSKay Sievers { 49fc14f2feSAl Viro mount_dev = simple_strtoul(str, NULL, 0); 502b2af54aSKay Sievers return 1; 512b2af54aSKay Sievers } 522b2af54aSKay Sievers __setup("devtmpfs.mount=", mount_param); 532b2af54aSKay Sievers 54fc14f2feSAl Viro static struct dentry *dev_mount(struct file_system_type *fs_type, int flags, 55fc14f2feSAl Viro const char *dev_name, void *data) 562b2af54aSKay Sievers { 57da5e4ef7SPeter Korsgaard #ifdef CONFIG_TMPFS 58fc14f2feSAl Viro return mount_single(fs_type, flags, data, shmem_fill_super); 59da5e4ef7SPeter Korsgaard #else 60fc14f2feSAl Viro return mount_single(fs_type, flags, data, ramfs_fill_super); 61da5e4ef7SPeter Korsgaard #endif 622b2af54aSKay Sievers } 632b2af54aSKay Sievers 642b2af54aSKay Sievers static struct file_system_type dev_fs_type = { 652b2af54aSKay Sievers .name = "devtmpfs", 66fc14f2feSAl Viro .mount = dev_mount, 672b2af54aSKay Sievers .kill_sb = kill_litter_super, 682b2af54aSKay Sievers }; 692b2af54aSKay Sievers 702b2af54aSKay Sievers #ifdef CONFIG_BLOCK 712b2af54aSKay Sievers static inline int is_blockdev(struct device *dev) 722b2af54aSKay Sievers { 732b2af54aSKay Sievers return dev->class == &block_class; 742b2af54aSKay Sievers } 752b2af54aSKay Sievers #else 762b2af54aSKay Sievers static inline int is_blockdev(struct device *dev) { return 0; } 772b2af54aSKay Sievers #endif 782b2af54aSKay Sievers 792780f1ffSAl Viro int devtmpfs_create_node(struct device *dev) 802780f1ffSAl Viro { 812780f1ffSAl Viro const char *tmp = NULL; 822780f1ffSAl Viro struct req req; 832780f1ffSAl Viro 842780f1ffSAl Viro if (!thread) 852780f1ffSAl Viro return 0; 862780f1ffSAl Viro 872780f1ffSAl Viro req.mode = 0; 882780f1ffSAl Viro req.name = device_get_devnode(dev, &req.mode, &tmp); 892780f1ffSAl Viro if (!req.name) 902780f1ffSAl Viro return -ENOMEM; 912780f1ffSAl Viro 922780f1ffSAl Viro if (req.mode == 0) 932780f1ffSAl Viro req.mode = 0600; 942780f1ffSAl Viro if (is_blockdev(dev)) 952780f1ffSAl Viro req.mode |= S_IFBLK; 962780f1ffSAl Viro else 972780f1ffSAl Viro req.mode |= S_IFCHR; 982780f1ffSAl Viro 992780f1ffSAl Viro req.dev = dev; 1002780f1ffSAl Viro 1012780f1ffSAl Viro init_completion(&req.done); 1022780f1ffSAl Viro 1032780f1ffSAl Viro spin_lock(&req_lock); 1042780f1ffSAl Viro req.next = requests; 1052780f1ffSAl Viro requests = &req; 1062780f1ffSAl Viro spin_unlock(&req_lock); 1072780f1ffSAl Viro 1082780f1ffSAl Viro wake_up_process(thread); 1092780f1ffSAl Viro wait_for_completion(&req.done); 1102780f1ffSAl Viro 1112780f1ffSAl Viro kfree(tmp); 1122780f1ffSAl Viro 1132780f1ffSAl Viro return req.err; 1142780f1ffSAl Viro } 1152780f1ffSAl Viro 1162780f1ffSAl Viro int devtmpfs_delete_node(struct device *dev) 1172780f1ffSAl Viro { 1182780f1ffSAl Viro const char *tmp = NULL; 1192780f1ffSAl Viro struct req req; 1202780f1ffSAl Viro 1212780f1ffSAl Viro if (!thread) 1222780f1ffSAl Viro return 0; 1232780f1ffSAl Viro 1242780f1ffSAl Viro req.name = device_get_devnode(dev, NULL, &tmp); 1252780f1ffSAl Viro if (!req.name) 1262780f1ffSAl Viro return -ENOMEM; 1272780f1ffSAl Viro 1282780f1ffSAl Viro req.mode = 0; 1292780f1ffSAl Viro req.dev = dev; 1302780f1ffSAl Viro 1312780f1ffSAl Viro init_completion(&req.done); 1322780f1ffSAl Viro 1332780f1ffSAl Viro spin_lock(&req_lock); 1342780f1ffSAl Viro req.next = requests; 1352780f1ffSAl Viro requests = &req; 1362780f1ffSAl Viro spin_unlock(&req_lock); 1372780f1ffSAl Viro 1382780f1ffSAl Viro wake_up_process(thread); 1392780f1ffSAl Viro wait_for_completion(&req.done); 1402780f1ffSAl Viro 1412780f1ffSAl Viro kfree(tmp); 1422780f1ffSAl Viro return req.err; 1432780f1ffSAl Viro } 1442780f1ffSAl Viro 145fbd48a69SAl Viro static int dev_mkdir(const char *name, umode_t mode) 1462b2af54aSKay Sievers { 1472b2af54aSKay Sievers struct dentry *dentry; 14869753a0fSAl Viro struct path path; 1492b2af54aSKay Sievers int err; 1502b2af54aSKay Sievers 15169753a0fSAl Viro dentry = kern_path_create(AT_FDCWD, name, &path, 1); 15269753a0fSAl Viro if (IS_ERR(dentry)) 15369753a0fSAl Viro return PTR_ERR(dentry); 1542b2af54aSKay Sievers 15569753a0fSAl Viro err = vfs_mkdir(path.dentry->d_inode, dentry, mode); 156015bf43bSKay Sievers if (!err) 157015bf43bSKay Sievers /* mark as kernel-created inode */ 1582780f1ffSAl Viro dentry->d_inode->i_private = &thread; 1592b2af54aSKay Sievers dput(dentry); 16069753a0fSAl Viro mutex_unlock(&path.dentry->d_inode->i_mutex); 16169753a0fSAl Viro path_put(&path); 1622b2af54aSKay Sievers return err; 1632b2af54aSKay Sievers } 1642b2af54aSKay Sievers 1652b2af54aSKay Sievers static int create_path(const char *nodepath) 1662b2af54aSKay Sievers { 167ed413ae6SKay Sievers char *path; 1682b2af54aSKay Sievers char *s; 1699d108d25SAl Viro int err = 0; 1702b2af54aSKay Sievers 1712b2af54aSKay Sievers /* parent directories do not exist, create them */ 172ed413ae6SKay Sievers path = kstrdup(nodepath, GFP_KERNEL); 1735da4e689SAl Viro if (!path) 1745da4e689SAl Viro return -ENOMEM; 1755da4e689SAl Viro 1762b2af54aSKay Sievers s = path; 177ed413ae6SKay Sievers for (;;) { 1782b2af54aSKay Sievers s = strchr(s, '/'); 1792b2af54aSKay Sievers if (!s) 1802b2af54aSKay Sievers break; 1812b2af54aSKay Sievers s[0] = '\0'; 1822b2af54aSKay Sievers err = dev_mkdir(path, 0755); 1832b2af54aSKay Sievers if (err && err != -EEXIST) 1842b2af54aSKay Sievers break; 1852b2af54aSKay Sievers s[0] = '/'; 1862b2af54aSKay Sievers s++; 1872b2af54aSKay Sievers } 1882b2af54aSKay Sievers kfree(path); 1892b2af54aSKay Sievers return err; 1902b2af54aSKay Sievers } 1912b2af54aSKay Sievers 192fbd48a69SAl Viro static int handle_create(const char *nodename, umode_t mode, struct device *dev) 1932b2af54aSKay Sievers { 1942b2af54aSKay Sievers struct dentry *dentry; 19569753a0fSAl Viro struct path path; 1962b2af54aSKay Sievers int err; 1972b2af54aSKay Sievers 19869753a0fSAl Viro dentry = kern_path_create(AT_FDCWD, nodename, &path, 0); 19969753a0fSAl Viro if (dentry == ERR_PTR(-ENOENT)) { 2002b2af54aSKay Sievers create_path(nodename); 20169753a0fSAl Viro dentry = kern_path_create(AT_FDCWD, nodename, &path, 0); 20200926996SKay Sievers } 20369753a0fSAl Viro if (IS_ERR(dentry)) 20469753a0fSAl Viro return PTR_ERR(dentry); 2052b2af54aSKay Sievers 20669753a0fSAl Viro err = vfs_mknod(path.dentry->d_inode, 2072b2af54aSKay Sievers dentry, mode, dev->devt); 20800926996SKay Sievers if (!err) { 20900926996SKay Sievers struct iattr newattrs; 21000926996SKay Sievers 21100926996SKay Sievers /* fixup possibly umasked mode */ 21200926996SKay Sievers newattrs.ia_mode = mode; 21300926996SKay Sievers newattrs.ia_valid = ATTR_MODE; 21400926996SKay Sievers mutex_lock(&dentry->d_inode->i_mutex); 21500926996SKay Sievers notify_change(dentry, &newattrs); 21600926996SKay Sievers mutex_unlock(&dentry->d_inode->i_mutex); 21700926996SKay Sievers 21800926996SKay Sievers /* mark as kernel-created inode */ 2192780f1ffSAl Viro dentry->d_inode->i_private = &thread; 22000926996SKay Sievers } 2212b2af54aSKay Sievers dput(dentry); 2222b2af54aSKay Sievers 22369753a0fSAl Viro mutex_unlock(&path.dentry->d_inode->i_mutex); 22469753a0fSAl Viro path_put(&path); 2252b2af54aSKay Sievers return err; 2262b2af54aSKay Sievers } 2272b2af54aSKay Sievers 2282b2af54aSKay Sievers static int dev_rmdir(const char *name) 2292b2af54aSKay Sievers { 2302b2af54aSKay Sievers struct nameidata nd; 2312b2af54aSKay Sievers struct dentry *dentry; 2322b2af54aSKay Sievers int err; 2332b2af54aSKay Sievers 2342780f1ffSAl Viro err = kern_path_parent(name, &nd); 2352b2af54aSKay Sievers if (err) 2362b2af54aSKay Sievers return err; 2372b2af54aSKay Sievers 2382b2af54aSKay Sievers mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); 2392b2af54aSKay Sievers dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len); 2402b2af54aSKay Sievers if (!IS_ERR(dentry)) { 241015bf43bSKay Sievers if (dentry->d_inode) { 2422780f1ffSAl Viro if (dentry->d_inode->i_private == &thread) 243015bf43bSKay Sievers err = vfs_rmdir(nd.path.dentry->d_inode, 244015bf43bSKay Sievers dentry); 2452b2af54aSKay Sievers else 246015bf43bSKay Sievers err = -EPERM; 247015bf43bSKay Sievers } else { 2482b2af54aSKay Sievers err = -ENOENT; 249015bf43bSKay Sievers } 2502b2af54aSKay Sievers dput(dentry); 2512b2af54aSKay Sievers } else { 2522b2af54aSKay Sievers err = PTR_ERR(dentry); 2532b2af54aSKay Sievers } 2542b2af54aSKay Sievers 255015bf43bSKay Sievers mutex_unlock(&nd.path.dentry->d_inode->i_mutex); 2562b2af54aSKay Sievers path_put(&nd.path); 2572b2af54aSKay Sievers return err; 2582b2af54aSKay Sievers } 2592b2af54aSKay Sievers 2602b2af54aSKay Sievers static int delete_path(const char *nodepath) 2612b2af54aSKay Sievers { 2622b2af54aSKay Sievers const char *path; 2632b2af54aSKay Sievers int err = 0; 2642b2af54aSKay Sievers 2652b2af54aSKay Sievers path = kstrdup(nodepath, GFP_KERNEL); 2662b2af54aSKay Sievers if (!path) 2672b2af54aSKay Sievers return -ENOMEM; 2682b2af54aSKay Sievers 269ed413ae6SKay Sievers for (;;) { 2702b2af54aSKay Sievers char *base; 2712b2af54aSKay Sievers 2722b2af54aSKay Sievers base = strrchr(path, '/'); 2732b2af54aSKay Sievers if (!base) 2742b2af54aSKay Sievers break; 2752b2af54aSKay Sievers base[0] = '\0'; 2762b2af54aSKay Sievers err = dev_rmdir(path); 2772b2af54aSKay Sievers if (err) 2782b2af54aSKay Sievers break; 2792b2af54aSKay Sievers } 2802b2af54aSKay Sievers 2812b2af54aSKay Sievers kfree(path); 2822b2af54aSKay Sievers return err; 2832b2af54aSKay Sievers } 2842b2af54aSKay Sievers 2852b2af54aSKay Sievers static int dev_mynode(struct device *dev, struct inode *inode, struct kstat *stat) 2862b2af54aSKay Sievers { 2872b2af54aSKay Sievers /* did we create it */ 2882780f1ffSAl Viro if (inode->i_private != &thread) 2892b2af54aSKay Sievers return 0; 2902b2af54aSKay Sievers 2912b2af54aSKay Sievers /* does the dev_t match */ 2922b2af54aSKay Sievers if (is_blockdev(dev)) { 2932b2af54aSKay Sievers if (!S_ISBLK(stat->mode)) 2942b2af54aSKay Sievers return 0; 2952b2af54aSKay Sievers } else { 2962b2af54aSKay Sievers if (!S_ISCHR(stat->mode)) 2972b2af54aSKay Sievers return 0; 2982b2af54aSKay Sievers } 2992b2af54aSKay Sievers if (stat->rdev != dev->devt) 3002b2af54aSKay Sievers return 0; 3012b2af54aSKay Sievers 3022b2af54aSKay Sievers /* ours */ 3032b2af54aSKay Sievers return 1; 3042b2af54aSKay Sievers } 3052b2af54aSKay Sievers 3062780f1ffSAl Viro static int handle_remove(const char *nodename, struct device *dev) 3072b2af54aSKay Sievers { 3082b2af54aSKay Sievers struct nameidata nd; 3092b2af54aSKay Sievers struct dentry *dentry; 3102b2af54aSKay Sievers struct kstat stat; 3112b2af54aSKay Sievers int deleted = 1; 3122b2af54aSKay Sievers int err; 3132b2af54aSKay Sievers 3142780f1ffSAl Viro err = kern_path_parent(nodename, &nd); 3152b2af54aSKay Sievers if (err) 3162780f1ffSAl Viro return err; 3172b2af54aSKay Sievers 3182b2af54aSKay Sievers mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); 3192b2af54aSKay Sievers dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len); 3202b2af54aSKay Sievers if (!IS_ERR(dentry)) { 3212b2af54aSKay Sievers if (dentry->d_inode) { 3222b2af54aSKay Sievers err = vfs_getattr(nd.path.mnt, dentry, &stat); 3232b2af54aSKay Sievers if (!err && dev_mynode(dev, dentry->d_inode, &stat)) { 3245e31d76fSKay Sievers struct iattr newattrs; 3255e31d76fSKay Sievers /* 3265e31d76fSKay Sievers * before unlinking this node, reset permissions 3275e31d76fSKay Sievers * of possible references like hardlinks 3285e31d76fSKay Sievers */ 3295e31d76fSKay Sievers newattrs.ia_uid = 0; 3305e31d76fSKay Sievers newattrs.ia_gid = 0; 3315e31d76fSKay Sievers newattrs.ia_mode = stat.mode & ~0777; 3325e31d76fSKay Sievers newattrs.ia_valid = 3335e31d76fSKay Sievers ATTR_UID|ATTR_GID|ATTR_MODE; 3345e31d76fSKay Sievers mutex_lock(&dentry->d_inode->i_mutex); 3355e31d76fSKay Sievers notify_change(dentry, &newattrs); 3365e31d76fSKay Sievers mutex_unlock(&dentry->d_inode->i_mutex); 3372b2af54aSKay Sievers err = vfs_unlink(nd.path.dentry->d_inode, 3382b2af54aSKay Sievers dentry); 3392b2af54aSKay Sievers if (!err || err == -ENOENT) 3402b2af54aSKay Sievers deleted = 1; 3412b2af54aSKay Sievers } 3422b2af54aSKay Sievers } else { 3432b2af54aSKay Sievers err = -ENOENT; 3442b2af54aSKay Sievers } 3452b2af54aSKay Sievers dput(dentry); 3462b2af54aSKay Sievers } else { 3472b2af54aSKay Sievers err = PTR_ERR(dentry); 3482b2af54aSKay Sievers } 3492b2af54aSKay Sievers mutex_unlock(&nd.path.dentry->d_inode->i_mutex); 3502b2af54aSKay Sievers 3512b2af54aSKay Sievers path_put(&nd.path); 3522b2af54aSKay Sievers if (deleted && strchr(nodename, '/')) 3532b2af54aSKay Sievers delete_path(nodename); 3542b2af54aSKay Sievers return err; 3552b2af54aSKay Sievers } 3562b2af54aSKay Sievers 3572b2af54aSKay Sievers /* 3582b2af54aSKay Sievers * If configured, or requested by the commandline, devtmpfs will be 3592b2af54aSKay Sievers * auto-mounted after the kernel mounted the root filesystem. 3602b2af54aSKay Sievers */ 361073120ccSKay Sievers int devtmpfs_mount(const char *mntdir) 3622b2af54aSKay Sievers { 3632b2af54aSKay Sievers int err; 3642b2af54aSKay Sievers 365fc14f2feSAl Viro if (!mount_dev) 3662b2af54aSKay Sievers return 0; 3672b2af54aSKay Sievers 3682780f1ffSAl Viro if (!thread) 3692b2af54aSKay Sievers return 0; 3702b2af54aSKay Sievers 371073120ccSKay Sievers err = sys_mount("devtmpfs", (char *)mntdir, "devtmpfs", MS_SILENT, NULL); 3722b2af54aSKay Sievers if (err) 3732b2af54aSKay Sievers printk(KERN_INFO "devtmpfs: error mounting %i\n", err); 3742b2af54aSKay Sievers else 3752b2af54aSKay Sievers printk(KERN_INFO "devtmpfs: mounted\n"); 3762b2af54aSKay Sievers return err; 3772b2af54aSKay Sievers } 3782b2af54aSKay Sievers 379f9e0b159SArnaud Lacombe static DECLARE_COMPLETION(setup_done); 3802780f1ffSAl Viro 381fbd48a69SAl Viro static int handle(const char *name, umode_t mode, struct device *dev) 3822780f1ffSAl Viro { 3832780f1ffSAl Viro if (mode) 3842780f1ffSAl Viro return handle_create(name, mode, dev); 3852780f1ffSAl Viro else 3862780f1ffSAl Viro return handle_remove(name, dev); 3872780f1ffSAl Viro } 3882780f1ffSAl Viro 3892780f1ffSAl Viro static int devtmpfsd(void *p) 3902780f1ffSAl Viro { 3912780f1ffSAl Viro char options[] = "mode=0755"; 3922780f1ffSAl Viro int *err = p; 3932780f1ffSAl Viro *err = sys_unshare(CLONE_NEWNS); 3942780f1ffSAl Viro if (*err) 3952780f1ffSAl Viro goto out; 3962780f1ffSAl Viro *err = sys_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, options); 3972780f1ffSAl Viro if (*err) 3982780f1ffSAl Viro goto out; 3992780f1ffSAl Viro sys_chdir("/.."); /* will traverse into overmounted root */ 4002780f1ffSAl Viro sys_chroot("."); 4012780f1ffSAl Viro complete(&setup_done); 4022780f1ffSAl Viro while (1) { 4032780f1ffSAl Viro spin_lock(&req_lock); 4042780f1ffSAl Viro while (requests) { 4052780f1ffSAl Viro struct req *req = requests; 4062780f1ffSAl Viro requests = NULL; 4072780f1ffSAl Viro spin_unlock(&req_lock); 4082780f1ffSAl Viro while (req) { 409e13889baSAl Viro struct req *next = req->next; 4102780f1ffSAl Viro req->err = handle(req->name, req->mode, req->dev); 4112780f1ffSAl Viro complete(&req->done); 412e13889baSAl Viro req = next; 4132780f1ffSAl Viro } 4142780f1ffSAl Viro spin_lock(&req_lock); 4152780f1ffSAl Viro } 41665e6757bSKautuk Consul __set_current_state(TASK_INTERRUPTIBLE); 4172780f1ffSAl Viro spin_unlock(&req_lock); 4182780f1ffSAl Viro schedule(); 4192780f1ffSAl Viro } 4202780f1ffSAl Viro return 0; 4212780f1ffSAl Viro out: 4222780f1ffSAl Viro complete(&setup_done); 4232780f1ffSAl Viro return *err; 4242780f1ffSAl Viro } 4252780f1ffSAl Viro 4262b2af54aSKay Sievers /* 4272b2af54aSKay Sievers * Create devtmpfs instance, driver-core devices will add their device 4282b2af54aSKay Sievers * nodes here. 4292b2af54aSKay Sievers */ 4302b2af54aSKay Sievers int __init devtmpfs_init(void) 4312b2af54aSKay Sievers { 4322780f1ffSAl Viro int err = register_filesystem(&dev_fs_type); 4332b2af54aSKay Sievers if (err) { 4342b2af54aSKay Sievers printk(KERN_ERR "devtmpfs: unable to register devtmpfs " 4352b2af54aSKay Sievers "type %i\n", err); 4362b2af54aSKay Sievers return err; 4372b2af54aSKay Sievers } 4382b2af54aSKay Sievers 4392780f1ffSAl Viro thread = kthread_run(devtmpfsd, &err, "kdevtmpfs"); 4402780f1ffSAl Viro if (!IS_ERR(thread)) { 4412780f1ffSAl Viro wait_for_completion(&setup_done); 4422780f1ffSAl Viro } else { 4432780f1ffSAl Viro err = PTR_ERR(thread); 4442780f1ffSAl Viro thread = NULL; 4452780f1ffSAl Viro } 4462780f1ffSAl Viro 4472780f1ffSAl Viro if (err) { 4482b2af54aSKay Sievers printk(KERN_ERR "devtmpfs: unable to create devtmpfs %i\n", err); 4492b2af54aSKay Sievers unregister_filesystem(&dev_fs_type); 4502b2af54aSKay Sievers return err; 4512b2af54aSKay Sievers } 4522b2af54aSKay Sievers 4532b2af54aSKay Sievers printk(KERN_INFO "devtmpfs: initialized\n"); 4542b2af54aSKay Sievers return 0; 4552b2af54aSKay Sievers } 456