Merge branch 'quilt/driver-core'

Conflicts:
	init/main.c

41 files changed, 501 insertions, 93 deletions

diff --git a/block/genhd.c b/block/genhd.c
index f4c64c2b303a..bc75f9cbc273 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -901,7 +901,7 @@ static struct attribute_group disk_attr_group = {
 	.attrs = disk_attrs,
 };
 
-static struct attribute_group *disk_attr_groups[] = {
+static const struct attribute_group *disk_attr_groups[] = {
 	&disk_attr_group,
 	NULL
 };
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 8f006f96ff53..ee377270beb9 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -8,6 +8,31 @@ config UEVENT_HELPER_PATH
 	  Path to uevent helper program forked by the kernel for
 	  every uevent.
 
+config DEVTMPFS
+	bool "Create a kernel maintained /dev tmpfs (EXPERIMENTAL)"
+	depends on HOTPLUG && SHMEM && TMPFS
+	help
+	  This creates a tmpfs filesystem, and mounts it at bootup
+	  and mounts it at /dev. The kernel driver core creates device
+	  nodes for all registered devices in that filesystem. All device
+	  nodes are owned by root and have the default mode of 0600.
+	  Userspace can add and delete the nodes as needed. This is
+	  intended to simplify bootup, and make it possible to delay
+	  the initial coldplug at bootup done by udev in userspace.
+	  It should also provide a simpler way for rescue systems
+	  to bring up a kernel with dynamic major/minor numbers.
+	  Meaningful symlinks, permissions and device ownership must
+	  still be handled by userspace.
+	  If unsure, say N here.
+
+config DEVTMPFS_MOUNT
+	bool "Automount devtmpfs at /dev"
+	depends on DEVTMPFS
+	help
+	  This will mount devtmpfs at /dev if the kernel mounts the root
+	  filesystem. It will not affect initramfs based mounting.
+	  If unsure, say N here.
+
 config STANDALONE
 	bool "Select only drivers that don't need compile-time external firmware" if EXPERIMENTAL
 	default y
diff --git a/drivers/base/Makefile b/drivers/base/Makefile
index b5b8ba512b28..68b225aa2266 100644
--- a/drivers/base/Makefile
+++ b/drivers/base/Makefile
@@ -4,6 +4,7 @@ obj-y			:= core.o sys.o bus.o dd.o \
 			   driver.o class.o platform.o \
 			   cpu.o firmware.o init.o map.o devres.o \
 			   attribute_container.o transport_class.o
+obj-$(CONFIG_DEVTMPFS)	+= devtmpfs.o
 obj-y			+= power/
 obj-$(CONFIG_HAS_DMA)	+= dma-mapping.o
 obj-$(CONFIG_ISA)	+= isa.o
diff --git a/drivers/base/base.h b/drivers/base/base.h
index ebb7ef4f1668..639914d91c01 100644
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -139,3 +139,9 @@ static inline void module_add_driver(struct module *mod,
 				     struct device_driver *drv) { }
 static inline void module_remove_driver(struct device_driver *drv) { }
 #endif
+
+#ifdef CONFIG_DEVTMPFS
+extern int devtmpfs_init(void);
+#else
+static inline int devtmpfs_init(void) { return 0; }
+#endif
diff --git a/drivers/base/core.c b/drivers/base/core.c
index f97261b84389..6629098c559f 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -341,7 +341,7 @@ static void device_remove_attributes(struct device *dev,
 }
 
 static int device_add_groups(struct device *dev,
-			     struct attribute_group **groups)
+			     const struct attribute_group **groups)
 {
 	int error = 0;
 	int i;
@@ -361,7 +361,7 @@ static int device_add_groups(struct device *dev,
 }
 
 static void device_remove_groups(struct device *dev,
-				 struct attribute_group **groups)
+				 const struct attribute_group **groups)
 {
 	int i;
 
@@ -929,6 +929,8 @@ int device_add(struct device *dev)
 		error = device_create_sys_dev_entry(dev);
 		if (error)
 			goto devtattrError;
+
+		devtmpfs_create_node(dev);
 	}
 
 	error = device_add_class_symlinks(dev);
@@ -1075,6 +1077,7 @@ void device_del(struct device *dev)
 	if (parent)
 		klist_del(&dev->p->knode_parent);
 	if (MAJOR(dev->devt)) {
+		devtmpfs_delete_node(dev);
 		device_remove_sys_dev_entry(dev);
 		device_remove_file(dev, &devt_attr);
 	}
diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
new file mode 100644
index 000000000000..51c410ffa145
--- /dev/null
+++ b/drivers/base/devtmpfs.c
@@ -0,0 +1,367 @@
+/*
+ * devtmpfs - kernel-maintained tmpfs-based /dev
+ *
+ * Copyright (C) 2009, Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * During bootup, before any driver core device is registered,
+ * devtmpfs, a tmpfs-based filesystem is created. Every driver-core
+ * device which requests a device node, will add a node in this
+ * filesystem. The node is named after the the name of the device,
+ * or the susbsytem can provide a custom name. All devices are
+ * owned by root and have a mode of 0600.
+ */
+
+#include <linux/kernel.h>
+#include <linux/syscalls.h>
+#include <linux/mount.h>
+#include <linux/device.h>
+#include <linux/genhd.h>
+#include <linux/namei.h>
+#include <linux/fs.h>
+#include <linux/shmem_fs.h>
+#include <linux/cred.h>
+#include <linux/init_task.h>
+
+static struct vfsmount *dev_mnt;
+
+#if defined CONFIG_DEVTMPFS_MOUNT
+static int dev_mount = 1;
+#else
+static int dev_mount;
+#endif
+
+static int __init mount_param(char *str)
+{
+	dev_mount = simple_strtoul(str, NULL, 0);
+	return 1;
+}
+__setup("devtmpfs.mount=", mount_param);
+
+static int dev_get_sb(struct file_system_type *fs_type, int flags,
+		      const char *dev_name, void *data, struct vfsmount *mnt)
+{
+	return get_sb_single(fs_type, flags, data, shmem_fill_super, mnt);
+}
+
+static struct file_system_type dev_fs_type = {
+	.name = "devtmpfs",
+	.get_sb = dev_get_sb,
+	.kill_sb = kill_litter_super,
+};
+
+#ifdef CONFIG_BLOCK
+static inline int is_blockdev(struct device *dev)
+{
+	return dev->class == &block_class;
+}
+#else
+static inline int is_blockdev(struct device *dev) { return 0; }
+#endif
+
+static int dev_mkdir(const char *name, mode_t mode)
+{
+	struct nameidata nd;
+	struct dentry *dentry;
+	int err;
+
+	err = vfs_path_lookup(dev_mnt->mnt_root, dev_mnt,
+			      name, LOOKUP_PARENT, &nd);
+	if (err)
+		return err;
+
+	dentry = lookup_create(&nd, 1);
+	if (!IS_ERR(dentry)) {
+		err = vfs_mkdir(nd.path.dentry->d_inode, dentry, mode);
+		dput(dentry);
+	} else {
+		err = PTR_ERR(dentry);
+	}
+	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+
+	path_put(&nd.path);
+	return err;
+}
+
+static int create_path(const char *nodepath)
+{
+	char *path;
+	struct nameidata nd;
+	int err = 0;
+
+	path = kstrdup(nodepath, GFP_KERNEL);
+	if (!path)
+		return -ENOMEM;
+
+	err = vfs_path_lookup(dev_mnt->mnt_root, dev_mnt,
+			      path, LOOKUP_PARENT, &nd);
+	if (err == 0) {
+		struct dentry *dentry;
+
+		/* create directory right away */
+		dentry = lookup_create(&nd, 1);
+		if (!IS_ERR(dentry)) {
+			err = vfs_mkdir(nd.path.dentry->d_inode,
+					dentry, 0775);
+			dput(dentry);
+		}
+		mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+
+		path_put(&nd.path);
+	} else if (err == -ENOENT) {
+		char *s;
+
+		/* parent directories do not exist, create them */
+		s = path;
+		while (1) {
+			s = strchr(s, '/');
+			if (!s)
+				break;
+			s[0] = '\0';
+			err = dev_mkdir(path, 0755);
+			if (err && err != -EEXIST)
+				break;
+			s[0] = '/';
+			s++;
+		}
+	}
+
+	kfree(path);
+	return err;
+}
+
+int devtmpfs_create_node(struct device *dev)
+{
+	const char *tmp = NULL;
+	const char *nodename;
+	const struct cred *curr_cred;
+	mode_t mode;
+	struct nameidata nd;
+	struct dentry *dentry;
+	int err;
+
+	if (!dev_mnt)
+		return 0;
+
+	nodename = device_get_nodename(dev, &tmp);
+	if (!nodename)
+		return -ENOMEM;
+
+	if (is_blockdev(dev))
+		mode = S_IFBLK|0600;
+	else
+		mode = S_IFCHR|0600;
+
+	curr_cred = override_creds(&init_cred);
+	err = vfs_path_lookup(dev_mnt->mnt_root, dev_mnt,
+			      nodename, LOOKUP_PARENT, &nd);
+	if (err == -ENOENT) {
+		/* create missing parent directories */
+		create_path(nodename);
+		err = vfs_path_lookup(dev_mnt->mnt_root, dev_mnt,
+				      nodename, LOOKUP_PARENT, &nd);
+		if (err)
+			goto out;
+	}
+
+	dentry = lookup_create(&nd, 0);
+	if (!IS_ERR(dentry)) {
+		err = vfs_mknod(nd.path.dentry->d_inode,
+				dentry, mode, dev->devt);
+		/* mark as kernel created inode */
+		if (!err)
+			dentry->d_inode->i_private = &dev_mnt;
+		dput(dentry);
+	} else {
+		err = PTR_ERR(dentry);
+	}
+	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+
+	path_put(&nd.path);
+out:
+	kfree(tmp);
+	revert_creds(curr_cred);
+	return err;
+}
+
+static int dev_rmdir(const char *name)
+{
+	struct nameidata nd;
+	struct dentry *dentry;
+	int err;
+
+	err = vfs_path_lookup(dev_mnt->mnt_root, dev_mnt,
+			      name, LOOKUP_PARENT, &nd);
+	if (err)
+		return err;
+
+	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+	dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);
+	if (!IS_ERR(dentry)) {
+		if (dentry->d_inode)
+			err = vfs_rmdir(nd.path.dentry->d_inode, dentry);
+		else
+			err = -ENOENT;
+		dput(dentry);
+	} else {
+		err = PTR_ERR(dentry);
+	}
+	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+
+	path_put(&nd.path);
+	return err;
+}
+
+static int delete_path(const char *nodepath)
+{
+	const char *path;
+	int err = 0;
+
+	path = kstrdup(nodepath, GFP_KERNEL);
+	if (!path)
+		return -ENOMEM;
+
+	while (1) {
+		char *base;
+
+		base = strrchr(path, '/');
+		if (!base)
+			break;
+		base[0] = '\0';
+		err = dev_rmdir(path);
+		if (err)
+			break;
+	}
+
+	kfree(path);
+	return err;
+}
+
+static int dev_mynode(struct device *dev, struct inode *inode, struct kstat *stat)
+{
+	/* did we create it */
+	if (inode->i_private != &dev_mnt)
+		return 0;
+
+	/* does the dev_t match */
+	if (is_blockdev(dev)) {
+		if (!S_ISBLK(stat->mode))
+			return 0;
+	} else {
+		if (!S_ISCHR(stat->mode))
+			return 0;
+	}
+	if (stat->rdev != dev->devt)
+		return 0;
+
+	/* ours */
+	return 1;
+}
+
+int devtmpfs_delete_node(struct device *dev)
+{
+	const char *tmp = NULL;
+	const char *nodename;
+	const struct cred *curr_cred;
+	struct nameidata nd;
+	struct dentry *dentry;
+	struct kstat stat;
+	int deleted = 1;
+	int err;
+
+	if (!dev_mnt)
+		return 0;
+
+	nodename = device_get_nodename(dev, &tmp);
+	if (!nodename)
+		return -ENOMEM;
+
+	curr_cred = override_creds(&init_cred);
+	err = vfs_path_lookup(dev_mnt->mnt_root, dev_mnt,
+			      nodename, LOOKUP_PARENT, &nd);
+	if (err)
+		goto out;
+
+	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+	dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);
+	if (!IS_ERR(dentry)) {
+		if (dentry->d_inode) {
+			err = vfs_getattr(nd.path.mnt, dentry, &stat);
+			if (!err && dev_mynode(dev, dentry->d_inode, &stat)) {
+				err = vfs_unlink(nd.path.dentry->d_inode,
+						 dentry);
+				if (!err || err == -ENOENT)
+					deleted = 1;
+			}
+		} else {
+			err = -ENOENT;
+		}
+		dput(dentry);
+	} else {
+		err = PTR_ERR(dentry);
+	}
+	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+
+	path_put(&nd.path);
+	if (deleted && strchr(nodename, '/'))
+		delete_path(nodename);
+out:
+	kfree(tmp);
+	revert_creds(curr_cred);
+	return err;
+}
+
+/*
+ * If configured, or requested by the commandline, devtmpfs will be
+ * auto-mounted after the kernel mounted the root filesystem.
+ */
+int devtmpfs_mount(const char *mountpoint)
+{
+	struct path path;
+	int err;
+
+	if (!dev_mount)
+		return 0;
+
+	if (!dev_mnt)
+		return 0;
+
+	err = kern_path(mountpoint, LOOKUP_FOLLOW, &path);
+	if (err)
+		return err;
+	err = do_add_mount(dev_mnt, &path, 0, NULL);
+	if (err)
+		printk(KERN_INFO "devtmpfs: error mounting %i\n", err);
+	else
+		printk(KERN_INFO "devtmpfs: mounted\n");
+	path_put(&path);
+	return err;
+}
+
+/*
+ * Create devtmpfs instance, driver-core devices will add their device
+ * nodes here.
+ */
+int __init devtmpfs_init(void)
+{
+	int err;
+	struct vfsmount *mnt;
+
+	err = register_filesystem(&dev_fs_type);
+	if (err) {
+		printk(KERN_ERR "devtmpfs: unable to register devtmpfs "
+		       "type %i\n", err);
+		return err;
+	}
+
+	mnt = kern_mount(&dev_fs_type);
+	if (IS_ERR(mnt)) {
+		err = PTR_ERR(mnt);
+		printk(KERN_ERR "devtmpfs: unable to create devtmpfs %i\n", err);
+		unregister_filesystem(&dev_fs_type);
+		return err;
+	}
+	dev_mnt = mnt;
+
+	printk(KERN_INFO "devtmpfs: initialized\n");
+	return 0;
+}
diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index 8ae0f63602e0..ed2ebd3c287d 100644
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -181,7 +181,7 @@ void put_driver(struct device_driver *drv)
 EXPORT_SYMBOL_GPL(put_driver);
 
 static int driver_add_groups(struct device_driver *drv,
-			     struct attribute_group **groups)
+			     const struct attribute_group **groups)
 {
 	int error = 0;
 	int i;
@@ -201,7 +201,7 @@ static int driver_add_groups(struct device_driver *drv,
 }
 
 static void driver_remove_groups(struct device_driver *drv,
-				 struct attribute_group **groups)
+				 const struct attribute_group **groups)
 {
 	int i;
 
diff --git a/drivers/base/init.c b/drivers/base/init.c
index 7bd9b6a5b01f..c8a934e79421 100644
--- a/drivers/base/init.c
+++ b/drivers/base/init.c
@@ -20,6 +20,7 @@
 void __init driver_init(void)
 {
 	/* These are the core pieces */
+	devtmpfs_init();
 	devices_init();
 	buses_init();
 	classes_init();
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index a52cc7fe45ea..92b39fc654c6 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -572,7 +572,7 @@ static struct attribute_group cciss_dev_attr_group = {
 	.attrs = cciss_dev_attrs,
 };
 
-static struct attribute_group *cciss_dev_attr_groups[] = {
+static const struct attribute_group *cciss_dev_attr_groups[] = {
 	&cciss_dev_attr_group,
 	NULL
 };
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 645237bda682..bed3503184e4 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -864,71 +864,67 @@ static const struct file_operations kmsg_fops = {
 	.write =	kmsg_write,
 };
 
-static const struct {
-	unsigned int		minor;
-	char			*name;
-	umode_t			mode;
-	const struct file_operations	*fops;
-	struct backing_dev_info	*dev_info;
-} devlist[] = { /* list of minor devices */
-	{1, "mem",     S_IRUSR | S_IWUSR | S_IRGRP, &mem_fops,
-		&directly_mappable_cdev_bdi},
+static const struct memdev {
+	const char *name;
+	const struct file_operations *fops;
+	struct backing_dev_info *dev_info;
+} devlist[] = {
+	[ 1] = { "mem", &mem_fops, &directly_mappable_cdev_bdi },
 #ifdef CONFIG_DEVKMEM
-	{2, "kmem",    S_IRUSR | S_IWUSR | S_IRGRP, &kmem_fops,
-		&directly_mappable_cdev_bdi},
+	[ 2] = { "kmem", &kmem_fops, &directly_mappable_cdev_bdi },
 #endif
-	{3, "null",    S_IRUGO | S_IWUGO,           &null_fops, NULL},
+	[ 3] = {"null", &null_fops, NULL },
 #ifdef CONFIG_DEVPORT
-	{4, "port",    S_IRUSR | S_IWUSR | S_IRGRP, &port_fops, NULL},
+	[ 4] = { "port", &port_fops, NULL },
 #endif
-	{5, "zero",    S_IRUGO | S_IWUGO,           &zero_fops, &zero_bdi},
-	{7, "full",    S_IRUGO | S_IWUGO,           &full_fops, NULL},
-	{8, "random",  S_IRUGO | S_IWUSR,           &random_fops, NULL},
-	{9, "urandom", S_IRUGO | S_IWUSR,           &urandom_fops, NULL},
-	{11,"kmsg",    S_IRUGO | S_IWUSR,           &kmsg_fops, NULL},
+	[ 5] = { "zero", &zero_fops, &zero_bdi },
+	[ 6] = { "full", &full_fops, NULL },
+	[ 7] = { "random", &random_fops, NULL },
+	[ 9] = { "urandom", &urandom_fops, NULL },
+	[11] = { "kmsg", &kmsg_fops, NULL },
 #ifdef CONFIG_CRASH_DUMP
-	{12,"oldmem",    S_IRUSR | S_IWUSR | S_IRGRP, &oldmem_fops, NULL},
+	[12] = { "oldmem", &oldmem_fops, NULL },
 #endif
 };
 
 static int memory_open(struct inode *inode, struct file *filp)
 {
-	int ret = 0;
-	int i;
+	int minor;
+	const struct memdev *dev;
+	int ret = -ENXIO;
 
 	lock_kernel();
 
-	for (i = 0; i < ARRAY_SIZE(devlist); i++) {
-		if (devlist[i].minor == iminor(inode)) {
-			filp->f_op = devlist[i].fops;
-			if (devlist[i].dev_info) {
-				filp->f_mapping->backing_dev_info =
-					devlist[i].dev_info;
-			}
+	minor = iminor(inode);
+	if (minor >= ARRAY_SIZE(devlist))
+		goto out;
 
-			break;
-		}
-	}
+	dev = &devlist[minor];
+	if (!dev->fops)
+		goto out;
 
-	if (i == ARRAY_SIZE(devlist))
-		ret = -ENXIO;
-	else
-		if (filp->f_op && filp->f_op->open)
-			ret = filp->f_op->open(inode, filp);
+	filp->f_op = dev->fops;
+	if (dev->dev_info)
+		filp->f_mapping->backing_dev_info = dev->dev_info;
 
+	if (dev->fops->open)
+		ret = dev->fops->open(inode, filp);
+	else
+		ret = 0;
+out:
 	unlock_kernel();
 	return ret;
 }
 
 static const struct file_operations memory_fops = {
-	.open		= memory_open,	/* just a selector for the real open */
+	.open		= memory_open,
 };
 
 static struct class *mem_class;
 
 static int __init chr_dev_init(void)
 {
-	int i;
+	int minor;
 	int err;
 
 	err = bdi_init(&zero_bdi);
@@ -939,10 +935,12 @@ static int __init chr_dev_init(void)
 		printk("unable to get major %d for memory devs\n", MEM_MAJOR);
 
 	mem_class = class_create(THIS_MODULE, "mem");
-	for (i = 0; i < ARRAY_SIZE(devlist); i++)
-		device_create(mem_class, NULL,
-			      MKDEV(MEM_MAJOR, devlist[i].minor), NULL,
-			      devlist[i].name);
+	for (minor = 1; minor < ARRAY_SIZE(devlist); minor++) {
+		if (!devlist[minor].name)
+			continue;
+		device_create(mem_class, NULL, MKDEV(MEM_MAJOR, minor),
+			      NULL, devlist[minor].name);
+	}
 
 	return 0;
 }
diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
index 97e656af2d22..9d0dfcbe2c1c 100644
--- a/drivers/firewire/core-device.c
+++ b/drivers/firewire/core-device.c
@@ -312,7 +312,7 @@ static void init_fw_attribute_group(struct device *dev,
 	group->groups[0] = &group->group;
 	group->groups[1] = NULL;
 	group->group.attrs = group->attrs;
-	dev->groups = group->groups;
+	dev->groups = (const struct attribute_group **) group->groups;
 }
 
 static ssize_t modalias_show(struct device *dev,
diff --git a/drivers/firmware/dmi-id.c b/drivers/firmware/dmi-id.c
index 5a76d056b9d0..dbdf6fadfc79 100644
--- a/drivers/firmware/dmi-id.c
+++ b/drivers/firmware/dmi-id.c
@@ -139,7 +139,7 @@ static struct attribute_group sys_dmi_attribute_group = {
 	.attrs = sys_dmi_attributes,
 };
 
-static struct attribute_group* sys_dmi_attribute_groups[] = {
+static const struct attribute_group* sys_dmi_attribute_groups[] = {
 	&sys_dmi_attribute_group,
 	NULL
 };
diff --git a/drivers/infiniband/hw/ehca/ehca_main.c b/drivers/infiniband/hw/ehca/ehca_main.c
index 5b635aa5947e..fb2d83c5bf01 100644
--- a/drivers/infiniband/hw/ehca/ehca_main.c
+++ b/drivers/infiniband/hw/ehca/ehca_main.c
@@ -623,7 +623,7 @@ static struct attribute_group ehca_drv_attr_grp = {
 	.attrs = ehca_drv_attrs
 };
 
-static struct attribute_group *ehca_drv_attr_groups[] = {
+static const struct attribute_group *ehca_drv_attr_groups[] = {
 	&ehca_drv_attr_grp,
 	NULL,
 };
diff --git a/drivers/infiniband/hw/ipath/ipath_kernel.h b/drivers/infiniband/hw/ipath/ipath_kernel.h
index 6ba4861dd6ac..b3d7efcdf021 100644
--- a/drivers/infiniband/hw/ipath/ipath_kernel.h
+++ b/drivers/infiniband/hw/ipath/ipath_kernel.h
@@ -1286,7 +1286,7 @@ struct device_driver;
 
 extern const char ib_ipath_version[];
 
-extern struct attribute_group *ipath_driver_attr_groups[];
+extern const struct attribute_group *ipath_driver_attr_groups[];
 
 int ipath_device_create_group(struct device *, struct ipath_devdata *);
 void ipath_device_remove_group(struct device *, struct ipath_devdata *);
diff --git a/drivers/infiniband/hw/ipath/ipath_sysfs.c b/drivers/infiniband/hw/ipath/ipath_sysfs.c
index a6c8efbdc0c9..b8cb2f145ae4 100644
--- a/drivers/infiniband/hw/ipath/ipath_sysfs.c
+++ b/drivers/infiniband/hw/ipath/ipath_sysfs.c
@@ -1069,7 +1069,7 @@ static ssize_t show_tempsense(struct device *dev,
 	return ret;
 }
 
-struct attribute_group *ipath_driver_attr_groups[] = {
+const struct attribute_group *ipath_driver_attr_groups[] = {
 	&driver_attr_group,
 	NULL,
 };
diff --git a/drivers/input/input.c b/drivers/input/input.c
index 7c237e6ac711..851791d955f3 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -1144,7 +1144,7 @@ static struct attribute_group input_dev_caps_attr_group = {
 	.attrs	= input_dev_caps_attrs,
 };
 
-static struct attribute_group *input_dev_attr_groups[] = {
+static const struct attribute_group *input_dev_attr_groups[] = {
 	&input_dev_attr_group,
 	&input_dev_id_attr_group,
 	&input_dev_caps_attr_group,
diff --git a/drivers/misc/enclosure.c b/drivers/misc/enclosure.c
index 348443bdb23b..b5dd532cbbd1 100644
--- a/drivers/misc/enclosure.c
+++ b/drivers/misc/enclosure.c
@@ -218,7 +218,7 @@ static void enclosure_component_release(struct device *dev)
 	put_device(dev->parent);
 }
 
-static struct attribute_group *enclosure_groups[];
+static const struct attribute_group *enclosure_groups[];
 
 /**
  * enclosure_component_register - add a particular component to an enclosure
@@ -507,7 +507,7 @@ static struct attribute_group enclosure_group = {
 	.attrs = enclosure_component_attrs,
 };
 
-static struct attribute_group *enclosure_groups[] = {
+static const struct attribute_group *enclosure_groups[] = {
 	&enclosure_group,
 	NULL
 };
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 06084dbf1277..2fb9d5f271ea 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -276,7 +276,7 @@ static struct attribute_group mmc_std_attr_group = {
 	.attrs = mmc_std_attrs,
 };
 
-static struct attribute_group *mmc_attr_groups[] = {
+static const struct attribute_group *mmc_attr_groups[] = {
 	&mmc_std_attr_group,
 	NULL,
 };
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index cd81c395e164..7ad646fe077e 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -314,7 +314,7 @@ static struct attribute_group sd_std_attr_group = {
 	.attrs = sd_std_attrs,
 };
 
-static struct attribute_group *sd_attr_groups[] = {
+static const struct attribute_group *sd_attr_groups[] = {
 	&sd_std_attr_group,
 	NULL,
 };
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index fac54a3fa3f1..05a16beabcc6 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -217,7 +217,7 @@ struct attribute_group mtd_group = {
 	.attrs		= mtd_attrs,
 };
 
-struct attribute_group *mtd_groups[] = {
+const struct attribute_group *mtd_groups[] = {
 	&mtd_group,
 	NULL,
 };
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 85d43c6bcb66..a8393258a728 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -273,7 +273,7 @@ static struct attribute_group subch_attr_group = {
 	.attrs = subch_attrs,
 };
 
-static struct attribute_group *default_subch_attr_groups[] = {
+static const struct attribute_group *default_subch_attr_groups[] = {
 	&subch_attr_group,
 	NULL,
 };
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 3c57c1a18bb8..66232bef788d 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -624,7 +624,7 @@ static struct attribute_group ccwdev_attr_group = {
 	.attrs = ccwdev_attrs,
 };
 
-static struct attribute_group *ccwdev_attr_groups[] = {
+static const struct attribute_group *ccwdev_attr_groups[] = {
 	&ccwdev_attr_group,
 	NULL,
 };
diff --git a/drivers/s390/net/netiucv.c b/drivers/s390/net/netiucv.c
index bb1183a2ed66..9e3a1061f09a 100644
--- a/drivers/s390/net/netiucv.c
+++ b/drivers/s390/net/netiucv.c
@@ -2159,7 +2159,7 @@ static struct attribute_group netiucv_drv_attr_group = {
 	.attrs = netiucv_drv_attrs,
 };
 
-static struct attribute_group *netiucv_drv_attr_groups[] = {
+static const struct attribute_group *netiucv_drv_attr_groups[] = {
 	&netiucv_drv_attr_group,
 	NULL,
 };
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index 021e503c8c44..1fbf7c78bba0 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -132,7 +132,7 @@ extern struct scsi_transport_template blank_transport_template;
 extern void __scsi_remove_device(struct scsi_device *);
 
 extern struct bus_type scsi_bus_type;
-extern struct attribute_group *scsi_sysfs_shost_attr_groups[];
+extern const struct attribute_group *scsi_sysfs_shost_attr_groups[];
 
 /* scsi_netlink.c */
 #ifdef CONFIG_SCSI_NETLINK
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 91482f2dcc50..fde54537d715 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -275,7 +275,7 @@ struct attribute_group scsi_shost_attr_group = {
 	.attrs =	scsi_sysfs_shost_attrs,
 };
 
-struct attribute_group *scsi_sysfs_shost_attr_groups[] = {
+const struct attribute_group *scsi_sysfs_shost_attr_groups[] = {
 	&scsi_shost_attr_group,
 	NULL
 };
@@ -745,7 +745,7 @@ static struct attribute_group scsi_sdev_attr_group = {
 	.attrs =	scsi_sdev_attrs,
 };
 
-static struct attribute_group *scsi_sdev_attr_groups[] = {
+static const struct attribute_group *scsi_sdev_attr_groups[] = {
 	&scsi_sdev_attr_group,
 	NULL
 };
diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
index 7f86534de269..45200fd68534 100644
--- a/drivers/uio/Kconfig
+++ b/drivers/uio/Kconfig
@@ -1,7 +1,6 @@
 menuconfig UIO
 	tristate "Userspace I/O drivers"
 	depends on !S390
-	default n
 	help
 	  Enable this to allow the userspace driver core code to be
 	  built.  This code allows userspace programs easy access to
@@ -16,7 +15,6 @@ if UIO
 config UIO_CIF
 	tristate "generic Hilscher CIF Card driver"
 	depends on PCI
-	default n
 	help
 	  Driver for Hilscher CIF DeviceNet and Profibus cards.  This
 	  driver requires a userspace component that handles all of the
@@ -48,7 +46,6 @@ config UIO_PDRV_GENIRQ
 
 config UIO_SMX
 	tristate "SMX cryptengine UIO interface"
-	default n
 	help
 	  Userspace IO interface to the Cryptography engine found on the
 	  Nias Digital SMX boards.  These will be available from Q4 2008
@@ -61,7 +58,6 @@ config UIO_SMX
 config UIO_AEC
 	tristate "AEC video timestamp device"
 	depends on PCI
-	default n
 	help
 
 	  UIO driver for the Adrienne Electronics Corporation PCI time
@@ -78,7 +74,6 @@ config UIO_AEC
 
 config UIO_SERCOS3
 	tristate "Automata Sercos III PCI card driver"
-	default n
 	help
 	  Userspace I/O interface for the Sercos III PCI card from
 	  Automata GmbH. The userspace part of this driver will be
diff --git a/drivers/usb/core/endpoint.c b/drivers/usb/core/endpoint.c
index bc39fc40bbde..fdfaa7885515 100644
--- a/drivers/usb/core/endpoint.c
+++ b/drivers/usb/core/endpoint.c
@@ -154,7 +154,7 @@ static struct attribute *ep_dev_attrs[] = {
 static struct attribute_group ep_dev_attr_grp = {
 	.attrs = ep_dev_attrs,
 };
-static struct attribute_group *ep_dev_groups[] = {
+static const struct attribute_group *ep_dev_groups[] = {
 	&ep_dev_attr_grp,
 	NULL
 };
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index b5c72e458943..7ec3041ae79e 100644
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -573,7 +573,7 @@ static struct attribute_group dev_string_attr_grp = {
 	.is_visible =	dev_string_attrs_are_visible,
 };
 
-struct attribute_group *usb_device_groups[] = {
+const struct attribute_group *usb_device_groups[] = {
 	&dev_attr_grp,
 	&dev_string_attr_grp,
 	NULL
@@ -799,7 +799,7 @@ static struct attribute_group intf_assoc_attr_grp = {
 	.is_visible =	intf_assoc_attrs_are_visible,
 };
 
-struct attribute_group *usb_interface_groups[] = {
+const struct attribute_group *usb_interface_groups[] = {
 	&intf_attr_grp,
 	&intf_assoc_attr_grp,
 	NULL
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index e2a8cfaade1d..c0e0ae2bb8e7 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -152,8 +152,8 @@ static inline int is_active(const struct usb_interface *f)
 extern const char *usbcore_name;
 
 /* sysfs stuff */
-extern struct attribute_group *usb_device_groups[];
-extern struct attribute_group *usb_interface_groups[];
+extern const struct attribute_group *usb_device_groups[];
+extern const struct attribute_group *usb_interface_groups[];
 
 /* usbfs stuff */
 extern struct mutex usbfs_mutex;
diff --git a/drivers/uwb/lc-dev.c b/drivers/uwb/lc-dev.c
index e9fe1bb7eb23..1097e81b56d0 100644
--- a/drivers/uwb/lc-dev.c
+++ b/drivers/uwb/lc-dev.c
@@ -255,7 +255,7 @@ static struct attribute_group dev_attr_group = {
 	.attrs = dev_attrs,
 };
 
-static struct attribute_group *groups[] = {
+static const struct attribute_group *groups[] = {
 	&dev_attr_group,
 	NULL,
 };
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index ea4e6cb29e13..e79e6285ad28 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -302,7 +302,7 @@ static struct attribute_group part_attr_group = {
 	.attrs = part_attrs,
 };
 
-static struct attribute_group *part_attr_groups[] = {
+static const struct attribute_group *part_attr_groups[] = {
 	&part_attr_group,
 #ifdef CONFIG_BLK_DEV_IO_TRACE
 	&blk_trace_attr_group,
diff --git a/include/linux/attribute_container.h b/include/linux/attribute_container.h
index 794ad74b1d61..c3ab81428c66 100644
--- a/include/linux/attribute_container.h
+++ b/include/linux/attribute_container.h
@@ -17,7 +17,7 @@ struct attribute_container {
 	struct list_head	node;
 	struct klist		containers;
 	struct class		*class;
-	struct attribute_group	*grp;
+	const struct attribute_group *grp;
 	struct device_attribute **attrs;
 	int (*match)(struct attribute_container *, struct device *);
 #define	ATTRIBUTE_CONTAINER_NO_CLASSDEVS	0x01
diff --git a/include/linux/device.h b/include/linux/device.h
index f16511b70e28..f7b7487c49eb 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -131,7 +131,7 @@ struct device_driver {
 	void (*shutdown) (struct device *dev);
 	int (*suspend) (struct device *dev, pm_message_t state);
 	int (*resume) (struct device *dev);
-	struct attribute_group **groups;
+	const struct attribute_group **groups;
 
 	struct dev_pm_ops *pm;
 
@@ -287,7 +287,7 @@ extern void class_destroy(struct class *cls);
  */
 struct device_type {
 	const char *name;
-	struct attribute_group **groups;
+	const struct attribute_group **groups;
 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
 	char *(*nodename)(struct device *dev);
 	void (*release)(struct device *dev);
@@ -411,7 +411,7 @@ struct device {
 
 	struct klist_node	knode_class;
 	struct class		*class;
-	struct attribute_group	**groups;	/* optional groups */
+	const struct attribute_group **groups;	/* optional groups */
 
 	void	(*release)(struct device *dev);
 };
@@ -538,6 +538,16 @@ extern void put_device(struct device *dev);
 
 extern void wait_for_device_probe(void);
 
+#ifdef CONFIG_DEVTMPFS
+extern int devtmpfs_create_node(struct device *dev);
+extern int devtmpfs_delete_node(struct device *dev);
+extern int devtmpfs_mount(const char *mountpoint);
+#else
+static inline int devtmpfs_create_node(struct device *dev) { return 0; }
+static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
+static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
+#endif
+
 /* drivers/base/power/shutdown.c */
 extern void device_shutdown(void);
 
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 9f25ab2899de..cc658558bbc6 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -885,7 +885,7 @@ struct net_device
 	/* class/net/name entry */
 	struct device		dev;
 	/* space for optional statistics and wireless sysfs groups */
-	struct attribute_group  *sysfs_groups[3];
+	const struct attribute_group *sysfs_groups[3];
 
 	/* rtnetlink link ops */
 	const struct rtnl_link_ops *rtnl_link_ops;
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index abff6c9b413c..e44e8c4337a9 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -38,6 +38,9 @@ static inline struct shmem_inode_info *SHMEM_I(struct inode *inode)
 	return container_of(inode, struct shmem_inode_info, vfs_inode);
 }
 
+extern int init_tmpfs(void);
+extern int shmem_fill_super(struct super_block *sb, void *data, int silent);
+
 #ifdef CONFIG_TMPFS_POSIX_ACL
 int shmem_permission(struct inode *, int);
 int shmem_acl_init(struct inode *, struct inode *);
diff --git a/include/linux/transport_class.h b/include/linux/transport_class.h
index eaec1ea9558e..9ae8da3e6407 100644
--- a/include/linux/transport_class.h
+++ b/include/linux/transport_class.h
@@ -55,7 +55,7 @@ struct anon_transport_class cls = {				\
 
 struct transport_container {
 	struct attribute_container ac;
-	struct attribute_group *statistics;
+	const struct attribute_group *statistics;
 };
 
 #define attribute_container_to_transport_container(x) \
diff --git a/init/do_mounts.c b/init/do_mounts.c
index 093f65915501..bb008d064c1a 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -415,7 +415,7 @@ void __init prepare_namespace(void)
 
 	mount_root();
 out:
+	devtmpfs_mount("dev");
 	sys_mount(".", "/", NULL, MS_MOVE, NULL);
 	sys_chroot(".");
 }
-
diff --git a/init/main.c b/init/main.c
index 59f911c3135c..2568d29b82b3 100644
--- a/init/main.c
+++ b/init/main.c
@@ -69,6 +69,7 @@
 #include <linux/kmemcheck.h>
 #include <linux/kmemtrace.h>
 #include <linux/sfi.h>
+#include <linux/shmem_fs.h>
 #include <trace/boot.h>
 
 #include <asm/io.h>
@@ -781,6 +782,7 @@ static void __init do_basic_setup(void)
 	init_workqueues();
 	cpuset_init_smp();
 	usermodehelper_init();
+	init_tmpfs();
 	driver_init();
 	init_irq_proc();
 	do_ctors();
diff --git a/mm/shmem.c b/mm/shmem.c
index d713239ce2ce..044465116ac3 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2298,8 +2298,7 @@ static void shmem_put_super(struct super_block *sb)
 	sb->s_fs_info = NULL;
 }
 
-static int shmem_fill_super(struct super_block *sb,
-			    void *data, int silent)
+int shmem_fill_super(struct super_block *sb, void *data, int silent)
 {
 	struct inode *inode;
 	struct dentry *root;
@@ -2519,7 +2518,7 @@ static struct file_system_type tmpfs_fs_type = {
 	.kill_sb	= kill_litter_super,
 };
 
-static int __init init_tmpfs(void)
+int __init init_tmpfs(void)
 {
 	int error;
 
@@ -2576,7 +2575,7 @@ static struct file_system_type tmpfs_fs_type = {
 	.kill_sb	= kill_litter_super,
 };
 
-static int __init init_tmpfs(void)
+int __init init_tmpfs(void)
 {
 	BUG_ON(register_filesystem(&tmpfs_fs_type) != 0);
 
@@ -2687,5 +2686,3 @@ int shmem_zero_setup(struct vm_area_struct *vma)
 	vma->vm_ops = &shmem_vm_ops;
 	return 0;
 }
-
-module_init(init_tmpfs)
diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
index 95f7a7a544b4..7f939ce29801 100644
--- a/net/bluetooth/hci_sysfs.c
+++ b/net/bluetooth/hci_sysfs.c
@@ -68,7 +68,7 @@ static struct attribute_group bt_link_group = {
 	.attrs = bt_link_attrs,
 };
 
-static struct attribute_group *bt_link_groups[] = {
+static const struct attribute_group *bt_link_groups[] = {
 	&bt_link_group,
 	NULL
 };
@@ -392,7 +392,7 @@ static struct attribute_group bt_host_group = {
 	.attrs = bt_host_attrs,
 };
 
-static struct attribute_group *bt_host_groups[] = {
+static const struct attribute_group *bt_host_groups[] = {
 	&bt_host_group,
 	NULL
 };
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 3994680c08b9..a51def23efdd 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -493,7 +493,7 @@ void netdev_unregister_kobject(struct net_device * net)
 int netdev_register_kobject(struct net_device *net)
 {
 	struct device *dev = &(net->dev);
-	struct attribute_group **groups = net->sysfs_groups;
+	const struct attribute_group **groups = net->sysfs_groups;
 
 	dev->class = &net_class;
 	dev->platform_data = net;