Driver Core patches for 2.6.10-rc1

diff -Nru a/fs/sysfs/bin.c b/fs/sysfs/bin.c
@@ -17,8 +17,8 @@
 static int
 fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
 {
-	struct bin_attribute * attr = dentry->d_fsdata;
-	struct kobject * kobj = dentry->d_parent->d_fsdata;
+	struct bin_attribute * attr = to_bin_attr(dentry);
+	struct kobject * kobj = to_kobj(dentry->d_parent);
 
 	return attr->read(kobj, buffer, off, count);
 }

@@ -60,8 +60,8 @@
 static int
 flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
 {
-	struct bin_attribute *attr = dentry->d_fsdata;
-	struct kobject *kobj = dentry->d_parent->d_fsdata;
+	struct bin_attribute *attr = to_bin_attr(dentry->d_parent);
+	struct kobject *kobj = to_kobj(dentry);
 
 	return attr->write(kobj, buffer, offset, count);
 }

@@ -95,7 +95,7 @@
 static int open(struct inode * inode, struct file * file)
 {
 	struct kobject *kobj = sysfs_get_kobject(file->f_dentry->d_parent);
-	struct bin_attribute * attr = file->f_dentry->d_fsdata;
+	struct bin_attribute * attr = to_bin_attr(file->f_dentry);
 	int error = -EINVAL;
 
 	if (!kobj || !attr)

@@ -130,8 +130,8 @@
 
 static int release(struct inode * inode, struct file * file)
 {
-	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
-	struct bin_attribute * attr = file->f_dentry->d_fsdata;
+	struct kobject * kobj = to_kobj(file->f_dentry->d_parent);
+	struct bin_attribute * attr = to_bin_attr(file->f_dentry);
 	u8 * buffer = file->private_data;
 
 	if (kobj) 

diff -Nru a/fs/sysfs/file.c b/fs/sysfs/file.c
@@ -67,7 +67,7 @@
 
 /**
  *	fill_read_buffer - allocate and fill buffer from object.
- *	@file:		file pointer.
+ *	@dentry:	dentry pointer.
  *	@buffer:	data buffer for file.
  *
  *	Allocate @buffer->page, if it hasn't been already, then call the

@@ -75,10 +75,10 @@
  *	data. 
  *	This is called only once, on the file's first read. 
  */
-static int fill_read_buffer(struct file * file, struct sysfs_buffer * buffer)
+static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer)
 {
-	struct attribute * attr = file->f_dentry->d_fsdata;
-	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+	struct attribute * attr = to_attr(dentry);
+	struct kobject * kobj = to_kobj(dentry->d_parent);
 	struct sysfs_ops * ops = buffer->ops;
 	int ret = 0;
 	ssize_t count;

@@ -150,7 +150,7 @@
 	ssize_t retval = 0;
 
 	if (!*ppos) {
-		if ((retval = fill_read_buffer(file,buffer)))
+		if ((retval = fill_read_buffer(file->f_dentry,buffer)))
 			return retval;
 	}
 	pr_debug("%s: count = %d, ppos = %lld, buf = %s\n",

@@ -197,10 +197,10 @@
  */
 
 static int 
-flush_write_buffer(struct file * file, struct sysfs_buffer * buffer, size_t count)
+flush_write_buffer(struct dentry * dentry, struct sysfs_buffer * buffer, size_t count)
 {
-	struct attribute * attr = file->f_dentry->d_fsdata;
-	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+	struct attribute * attr = to_attr(dentry);
+	struct kobject * kobj = to_kobj(dentry->d_parent);
 	struct sysfs_ops * ops = buffer->ops;
 
 	return ops->store(kobj,attr,buffer->page,count);

@@ -231,7 +231,7 @@
 
 	count = fill_write_buffer(buffer,buf,count);
 	if (count > 0)
-		count = flush_write_buffer(file,buffer,count);
+		count = flush_write_buffer(file->f_dentry,buffer,count);
 	if (count > 0)
 		*ppos += count;
 	return count;

@@ -240,7 +240,7 @@
 static int check_perm(struct inode * inode, struct file * file)
 {
 	struct kobject *kobj = sysfs_get_kobject(file->f_dentry->d_parent);
-	struct attribute * attr = file->f_dentry->d_fsdata;
+	struct attribute * attr = to_attr(file->f_dentry);
 	struct sysfs_buffer * buffer;
 	struct sysfs_ops * ops = NULL;
 	int error = 0;

@@ -321,8 +321,8 @@
 
 static int sysfs_release(struct inode * inode, struct file * filp)
 {
-	struct kobject * kobj = filp->f_dentry->d_parent->d_fsdata;
-	struct attribute * attr = filp->f_dentry->d_fsdata;
+	struct kobject * kobj = to_kobj(filp->f_dentry->d_parent);
+	struct attribute * attr = to_attr(filp->f_dentry);
 	struct sysfs_buffer * buffer = filp->private_data;
 
 	if (kobj) 

diff -Nru a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
@@ -16,14 +16,30 @@
 extern void sysfs_put_link(struct dentry *, struct nameidata *);
 extern struct rw_semaphore sysfs_rename_sem;
 
+static inline struct kobject * to_kobj(struct dentry * dentry)
+{
+	return ((struct kobject *) dentry->d_fsdata);
+}
+
+static inline struct attribute * to_attr(struct dentry * dentry)
+{
+	return ((struct attribute *) dentry->d_fsdata);
+}
+
+static inline struct bin_attribute * to_bin_attr(struct dentry * dentry)
+{
+	return ((struct bin_attribute *) dentry->d_fsdata);
+}
+
 static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)
 {
 	struct kobject * kobj = NULL;
 
 	spin_lock(&dcache_lock);
 	if (!d_unhashed(dentry))
-		kobj = kobject_get(dentry->d_fsdata);
+		kobj = kobject_get(to_kobj(dentry));
 	spin_unlock(&dcache_lock);
 
 	return kobj;
 }
+

diff -Nru a/fs/sysfs/bin.c b/fs/sysfs/bin.c
@@ -60,8 +60,8 @@
 static int
 flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
 {
-	struct bin_attribute *attr = to_bin_attr(dentry->d_parent);
-	struct kobject *kobj = to_kobj(dentry);
+	struct bin_attribute *attr = to_bin_attr(dentry);
+	struct kobject *kobj = to_kobj(dentry->d_parent);
 
 	return attr->write(kobj, buffer, offset, count);
 }

diff -Nru a/fs/sysfs/bin.c b/fs/sysfs/bin.c
@@ -160,24 +160,26 @@
 {
 	struct dentry * dentry;
 	struct dentry * parent;
+	umode_t mode = (attr->attr.mode & S_IALLUGO) | S_IFREG;
 	int error = 0;
 
-	if (!kobj || !attr)
-		return -EINVAL;
+	BUG_ON(!kobj || !kobj->dentry || !attr);
 
 	parent = kobj->dentry;
 
 	down(&parent->d_inode->i_sem);
 	dentry = sysfs_get_dentry(parent,attr->attr.name);
 	if (!IS_ERR(dentry)) {
-		dentry->d_fsdata = (void *)attr;
-		error = sysfs_create(dentry,
-				     (attr->attr.mode & S_IALLUGO) | S_IFREG,
-				     NULL);
+		error = sysfs_create(dentry, mode, NULL);
 		if (!error) {
 			dentry->d_inode->i_size = attr->size;
 			dentry->d_inode->i_fop = &bin_fops;
+			error = sysfs_make_dirent(parent->d_fsdata, dentry,
+						  (void *) attr, mode,
+						  SYSFS_KOBJ_BIN_ATTR);
 		}
+		if (error)
+			d_drop(dentry);
 		dput(dentry);
 	} else
 		error = PTR_ERR(dentry);

135 lines not on this page · raw message

diff -Nru a/fs/sysfs/file.c b/fs/sysfs/file.c
@@ -346,19 +346,22 @@
 };
 
 
-int sysfs_add_file(struct dentry * dir, const struct attribute * attr)
+int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type)
 {
 	struct dentry * dentry;
-	int error;
+	struct sysfs_dirent * parent_sd = dir->d_fsdata;
+	umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
+	int error = 0;
 
 	down(&dir->d_inode->i_sem);
 	dentry = sysfs_get_dentry(dir,attr->name);
 	if (!IS_ERR(dentry)) {
-		error = sysfs_create(dentry,
-				     (attr->mode & S_IALLUGO) | S_IFREG,
-				     init_file);
+		error = sysfs_create(dentry, mode, init_file);
 		if (!error)
-			dentry->d_fsdata = (void *)attr;
+			error = sysfs_make_dirent(parent_sd, dentry,
+						(void *) attr, mode, type);
+		if (error)
+			d_drop(dentry);
 		dput(dentry);
 	} else
 		error = PTR_ERR(dentry);

@@ -375,9 +378,10 @@
 
 int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
 {
-	if (kobj && attr)
-		return sysfs_add_file(kobj->dentry,attr);
-	return -EINVAL;
+	BUG_ON(!kobj || !kobj->dentry || !attr);
+
+	return sysfs_add_file(kobj->dentry, attr, SYSFS_KOBJ_ATTR);
+
 }
 
 

@@ -409,7 +413,8 @@
 			 */
 			dput(victim);
 			res = 0;
-		}
+		} else
+			d_drop(victim);
 		
 		/**
 		 * Drop the reference acquired from sysfs_get_dentry() above.

diff -Nru a/fs/sysfs/group.c b/fs/sysfs/group.c
@@ -31,7 +31,7 @@
 	int error = 0;
 
 	for (attr = grp->attrs; *attr && !error; attr++) {
-		error = sysfs_add_file(dir,*attr);
+		error = sysfs_add_file(dir, *attr, SYSFS_KOBJ_ATTR);
 	}
 	if (error)
 		remove_files(dir,grp);

@@ -44,6 +44,8 @@
 {
 	struct dentry * dir;
 	int error;
+
+	BUG_ON(!kobj || !kobj->dentry);
 
 	if (grp->name) {
 		error = sysfs_create_subdir(kobj,grp->name,&dir);

diff -Nru a/fs/sysfs/inode.c b/fs/sysfs/inode.c
@@ -11,6 +11,8 @@
 #include <linux/pagemap.h>
 #include <linux/namei.h>
 #include <linux/backing-dev.h>
+#include "sysfs.h"
+
 extern struct super_block * sysfs_sb;
 
 static struct address_space_operations sysfs_aops = {

@@ -91,6 +93,7 @@
 void sysfs_hash_and_remove(struct dentry * dir, const char * name)
 {
 	struct dentry * victim;
+	struct sysfs_dirent * sd;
 
 	down(&dir->d_inode->i_sem);
 	victim = sysfs_get_dentry(dir,name);

@@ -101,14 +104,17 @@
 			pr_debug("sysfs: Removing %s (%d)\n", victim->d_name.name,
 				 atomic_read(&victim->d_count));
 
+			sd = victim->d_fsdata;
 			d_drop(victim);
 			/* release the target kobject in case of 
 			 * a symlink
 			 */
 			if (S_ISLNK(victim->d_inode->i_mode))
-				kobject_put(victim->d_fsdata);
+				kobject_put(sd->s_element);
+			list_del_init(&sd->s_sibling);
 			simple_unlink(dir->d_inode,victim);
-		}
+		} else
+			d_drop(victim);
 		/*
 		 * Drop reference from sysfs_get_dentry() above.
 		 */

diff -Nru a/fs/sysfs/mount.c b/fs/sysfs/mount.c
@@ -22,6 +22,13 @@
 	.drop_inode	= generic_delete_inode,
 };
 
+struct sysfs_dirent sysfs_root = {
+	.s_sibling	= LIST_HEAD_INIT(sysfs_root.s_sibling),
+	.s_children	= LIST_HEAD_INIT(sysfs_root.s_children),
+	.s_element	= NULL,
+	.s_type		= SYSFS_ROOT,
+};
+
 static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
 {
 	struct inode *inode;

@@ -50,6 +57,7 @@
 		iput(inode);
 		return -ENOMEM;
 	}
+	root->d_fsdata = &sysfs_root;
 	sb->s_root = root;
 	return 0;
 }

diff -Nru a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
@@ -55,6 +55,36 @@
 	}
 }
 
+static int sysfs_add_link(struct dentry * dentry, char * name, struct kobject * target)
+{
+	struct sysfs_dirent * parent_sd = dentry->d_parent->d_fsdata;
+	struct sysfs_symlink * sl;
+	int error = 0;
+
+	error = -ENOMEM;
+	sl = kmalloc(sizeof(*sl), GFP_KERNEL);
+	if (!sl)
+		goto exit1;
+
+	sl->link_name = kmalloc(strlen(name) + 1, GFP_KERNEL);
+	if (!sl->link_name)
+		goto exit2;
+
+	strcpy(sl->link_name, name);
+	sl->target_kobj = kobject_get(target);
+
+	error = sysfs_make_dirent(parent_sd, dentry, sl, S_IFLNK|S_IRWXUGO,
+				SYSFS_KOBJ_LINK);
+	if (!error)
+		return 0;
+
+	kfree(sl->link_name);
+exit2:
+	kfree(sl);
+exit1:
+	return error;
+}
+
 /**
  *	sysfs_create_link - create symlink between two objects.
  *	@kobj:	object whose directory we're creating the link in.

@@ -67,15 +97,16 @@
 	struct dentry * d;
 	int error = 0;
 
+	BUG_ON(!kobj || !kobj->dentry || !name);
+
 	down(&dentry->d_inode->i_sem);
 	d = sysfs_get_dentry(dentry,name);
 	if (!IS_ERR(d)) {
 		error = sysfs_create(d, S_IFLNK|S_IRWXUGO, init_symlink);
 		if (!error)
-			/* 
-			 * associate the link dentry with the target kobject 
-			 */
-			d->d_fsdata = kobject_get(target);
+			error = sysfs_add_link(d, name, target);
+		if (error)
+			d_drop(d);
 		dput(d);
 	} else 
 		error = PTR_ERR(d);

diff -Nru a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
@@ -4,9 +4,11 @@
 extern struct inode * sysfs_new_inode(mode_t mode);
 extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
 
+extern int sysfs_make_dirent(struct sysfs_dirent *, struct dentry *, void *,
+				umode_t, int);
 extern struct dentry * sysfs_get_dentry(struct dentry *, const char *);
 
-extern int sysfs_add_file(struct dentry * dir, const struct attribute * attr);
+extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
 extern void sysfs_hash_and_remove(struct dentry * dir, const char * name);
 
 extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);

@@ -16,19 +18,27 @@
 extern void sysfs_put_link(struct dentry *, struct nameidata *);
 extern struct rw_semaphore sysfs_rename_sem;
 
+struct sysfs_symlink {
+	char * link_name;
+	struct kobject * target_kobj;
+};
+
 static inline struct kobject * to_kobj(struct dentry * dentry)
 {
-	return ((struct kobject *) dentry->d_fsdata);
+	struct sysfs_dirent * sd = dentry->d_fsdata;
+	return ((struct kobject *) sd->s_element);
 }
 
 static inline struct attribute * to_attr(struct dentry * dentry)
 {
-	return ((struct attribute *) dentry->d_fsdata);
+	struct sysfs_dirent * sd = dentry->d_fsdata;
+	return ((struct attribute *) sd->s_element);
 }
 
 static inline struct bin_attribute * to_bin_attr(struct dentry * dentry)
 {
-	return ((struct bin_attribute *) dentry->d_fsdata);
+	struct sysfs_dirent * sd = dentry->d_fsdata;
+	return ((struct bin_attribute *) sd->s_element);
 }
 
 static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)

@@ -36,10 +46,27 @@
 	struct kobject * kobj = NULL;
 
 	spin_lock(&dcache_lock);
-	if (!d_unhashed(dentry))
-		kobj = kobject_get(to_kobj(dentry));
+	if (!d_unhashed(dentry)) {
+		struct sysfs_dirent * sd = dentry->d_fsdata;
+		if (sd->s_type & SYSFS_KOBJ_LINK) {
+			struct sysfs_symlink * sl = sd->s_element;
+			kobj = kobject_get(sl->target_kobj);
+		} else
+			kobj = kobject_get(sd->s_element);
+	}
 	spin_unlock(&dcache_lock);
 
 	return kobj;
+}
+
+static inline void release_sysfs_dirent(struct sysfs_dirent * sd)
+{
+	if (sd->s_type & SYSFS_KOBJ_LINK) {
+		struct sysfs_symlink * sl = sd->s_element;
+		kfree(sl->link_name);
+		kobject_put(sl->target_kobj);
+		kfree(sl);
+	}
+	kfree(sd);
 }
 

diff -Nru a/include/linux/sysfs.h b/include/linux/sysfs.h
@@ -9,6 +9,8 @@
 #ifndef _SYSFS_H_
 #define _SYSFS_H_
 
+#include <asm/atomic.h>
+
 struct kobject;
 struct module;
 

@@ -56,6 +58,23 @@
 	ssize_t	(*show)(struct kobject *, struct attribute *,char *);
 	ssize_t	(*store)(struct kobject *,struct attribute *,const char *, size_t);
 };
+
+struct sysfs_dirent {
+	atomic_t		s_count;
+	struct list_head	s_sibling;
+	struct list_head	s_children;
+	void 			* s_element;
+	int			s_type;
+	umode_t			s_mode;
+	struct dentry		* s_dentry;
+};
+
+#define SYSFS_ROOT		0x0001
+#define SYSFS_DIR		0x0002
+#define SYSFS_KOBJ_ATTR 	0x0004
+#define SYSFS_KOBJ_BIN_ATTR	0x0008
+#define SYSFS_KOBJ_LINK 	0x0020
+#define SYSFS_NOT_PINNED	(SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR | SYSFS_KOBJ_LINK)
 
 #ifdef CONFIG_SYSFS
 

diff -Nru a/fs/sysfs/dir.c b/fs/sysfs/dir.c
@@ -19,7 +19,7 @@
 	if (sd) {
 		BUG_ON(sd->s_dentry != dentry);
 		sd->s_dentry = NULL;
-		release_sysfs_dirent(sd);
+		sysfs_put(sd);
 	}
 	iput(inode);
 }

@@ -61,7 +61,7 @@
 	sd->s_mode = mode;
 	sd->s_type = type;
 	sd->s_dentry = dentry;
-	dentry->d_fsdata = sd;
+	dentry->d_fsdata = sysfs_get(sd);
 	dentry->d_op = &sysfs_dentry_ops;
 
 	return 0;

@@ -146,6 +146,7 @@
 	d_delete(d);
 	sd = d->d_fsdata;
  	list_del_init(&sd->s_sibling);
+	sysfs_put(sd);
 	if (d->d_inode)
 		simple_rmdir(parent->d_inode,d);
 

@@ -173,49 +174,22 @@
 
 void sysfs_remove_dir(struct kobject * kobj)
 {
-	struct list_head * node;
 	struct dentry * dentry = dget(kobj->dentry);
+	struct sysfs_dirent * parent_sd = dentry->d_fsdata;
+	struct sysfs_dirent * sd, * tmp;
 
 	if (!dentry)
 		return;
 
 	pr_debug("sysfs %s: removing dir\n",dentry->d_name.name);
 	down(&dentry->d_inode->i_sem);
-
-	spin_lock(&dcache_lock);
-restart:
-	node = dentry->d_subdirs.next;
-	while (node != &dentry->d_subdirs) {
-		struct dentry * d = list_entry(node,struct dentry,d_child);
-
-		node = node->next;
-		pr_debug(" o %s (%d): ",d->d_name.name,atomic_read(&d->d_count));
-		if (!d_unhashed(d) && (d->d_inode)) {
-			struct sysfs_dirent * sd = d->d_fsdata;
-			d = dget_locked(d);
-			pr_debug("removing");
-
-			/**
-			 * Unlink and unhash.
-			 */
-			__d_drop(d);
-			spin_unlock(&dcache_lock);
-			/* release the target kobject in case of 
-			 * a symlink
-			 */
-			if (S_ISLNK(d->d_inode->i_mode))
-				kobject_put(sd->s_element);
-			
-			list_del_init(&sd->s_sibling);
-			simple_unlink(dentry->d_inode,d);
-			dput(d);
-			pr_debug(" done\n");
-			spin_lock(&dcache_lock);
-			/* re-acquired dcache_lock, need to restart */
-			goto restart;
-		}
+	list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) {
+		if (!sd->s_element)
+			continue;
+		list_del_init(&sd->s_sibling);
+		sysfs_drop_dentry(sd, dentry);
+		sysfs_put(sd);
 	}
-	spin_unlock(&dcache_lock);
 	up(&dentry->d_inode->i_sem);
 
 	remove_dir(dentry);

116 lines not on this page · raw message

diff -Nru a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
@@ -14,6 +14,9 @@
 extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);
 extern void sysfs_remove_subdir(struct dentry *);
 
+extern const unsigned char * sysfs_get_name(struct sysfs_dirent *sd);
+extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent);
+
 extern int sysfs_follow_link(struct dentry *, struct nameidata *);
 extern void sysfs_put_link(struct dentry *, struct nameidata *);
 extern struct rw_semaphore sysfs_rename_sem;

@@ -68,5 +71,20 @@
 		kfree(sl);
 	}
 	kfree(sd);
+}
+
+static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
+{
+	if (sd) {
+		WARN_ON(!atomic_read(&sd->s_count));
+		atomic_inc(&sd->s_count);
+	}
+	return sd;
+}
+
+static inline void sysfs_put(struct sysfs_dirent * sd)
+{
+	if (atomic_dec_and_test(&sd->s_count))
+		release_sysfs_dirent(sd);
 }
 

diff -Nru a/fs/sysfs/dir.c b/fs/sysfs/dir.c
@@ -70,7 +70,7 @@
 static int init_dir(struct inode * inode)
 {
 	inode->i_op = &simple_dir_inode_operations;
-	inode->i_fop = &simple_dir_operations;
+	inode->i_fop = &sysfs_dir_operations;
 
 	/* directory inodes start off with i_nlink == 2 (for "." entry) */
 	inode->i_nlink++;

@@ -232,6 +232,145 @@
 
 	return error;
 }
+
+static int sysfs_dir_open(struct inode *inode, struct file *file)
+{
+	struct dentry * dentry = file->f_dentry;
+	struct sysfs_dirent * parent_sd = dentry->d_fsdata;
+
+	down(&dentry->d_inode->i_sem);
+	file->private_data = sysfs_new_dirent(parent_sd, NULL);
+	up(&dentry->d_inode->i_sem);
+
+	return file->private_data ? 0 : -ENOMEM;
+
+}
+
+static int sysfs_dir_close(struct inode *inode, struct file *file)
+{
+	struct dentry * dentry = file->f_dentry;
+	struct sysfs_dirent * cursor = file->private_data;
+
+	down(&dentry->d_inode->i_sem);
+	list_del_init(&cursor->s_sibling);
+	up(&dentry->d_inode->i_sem);
+	sysfs_put(file->private_data);
+
+	return 0;
+}
+
+/* Relationship between s_mode and the DT_xxx types */
+static inline unsigned char dt_type(struct sysfs_dirent *sd)
+{
+	return (sd->s_mode >> 12) & 15;
+}
+
+static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
+{
+	struct dentry *dentry = filp->f_dentry;
+	struct sysfs_dirent * parent_sd = dentry->d_fsdata;
+	struct sysfs_dirent *cursor = filp->private_data;
+	struct list_head *p, *q = &cursor->s_sibling;
+	ino_t ino;
+	int i = filp->f_pos;
+
+	switch (i) {
+		case 0:
+			ino = dentry->d_inode->i_ino;
+			if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
+				break;
+			filp->f_pos++;
+			i++;
+			/* fallthrough */
+		case 1:
+			ino = parent_ino(dentry);
+			if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
+				break;
+			filp->f_pos++;
+			i++;
+			/* fallthrough */
+		default:
+			if (filp->f_pos == 2) {
+				list_del(q);
+				list_add(q, &parent_sd->s_children);
+			}
+			for (p=q->next; p!= &parent_sd->s_children; p=p->next) {
+				struct sysfs_dirent *next;
+				const char * name;
+				int len;
+
+				next = list_entry(p, struct sysfs_dirent,
+						   s_sibling);
+				if (!next->s_element)
+					continue;
+
+				name = sysfs_get_name(next);
+				len = strlen(name);
+				if (next->s_dentry)
+					ino = next->s_dentry->d_inode->i_ino;
+				else
+					ino = iunique(sysfs_sb, 2);
+
+				if (filldir(dirent, name, len, filp->f_pos, ino,
+						 dt_type(next)) < 0)
+					return 0;
+
+				list_del(q);
+				list_add(q, p);
+				p = q;
+				filp->f_pos++;
+			}
+	}
+	return 0;
+}
+
+static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
+{
+	struct dentry * dentry = file->f_dentry;
+
+	down(&dentry->d_inode->i_sem);
+	switch (origin) {
+		case 1:
+			offset += file->f_pos;
+		case 0:
+			if (offset >= 0)
+				break;
+		default:
+			up(&file->f_dentry->d_inode->i_sem);
+			return -EINVAL;
+	}
+	if (offset != file->f_pos) {
+		file->f_pos = offset;
+		if (file->f_pos >= 2) {
+			struct sysfs_dirent *sd = dentry->d_fsdata;
+			struct sysfs_dirent *cursor = file->private_data;
+			struct list_head *p;
+			loff_t n = file->f_pos - 2;
+
+			list_del(&cursor->s_sibling);
+			p = sd->s_children.next;
+			while (n && p != &sd->s_children) {
+				struct sysfs_dirent *next;
+				next = list_entry(p, struct sysfs_dirent,
+						   s_sibling);
+				if (next->s_element)
+					n--;
+				p = p->next;
+			}
+			list_add_tail(&cursor->s_sibling, p);
+		}
+	}
+	up(&dentry->d_inode->i_sem);
+	return offset;
+}
+
+struct file_operations sysfs_dir_operations = {
+	.open		= sysfs_dir_open,
+	.release	= sysfs_dir_close,
+	.llseek		= sysfs_dir_lseek,
+	.read		= generic_read_dir,
+	.readdir	= sysfs_readdir,
+};
 
 EXPORT_SYMBOL_GPL(sysfs_create_dir);
 EXPORT_SYMBOL_GPL(sysfs_remove_dir);

diff -Nru a/fs/sysfs/mount.c b/fs/sysfs/mount.c
@@ -43,7 +43,7 @@
 	inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO);
 	if (inode) {
 		inode->i_op = &simple_dir_inode_operations;
-		inode->i_fop = &simple_dir_operations;
+		inode->i_fop = &sysfs_dir_operations;
 		/* directory inodes start off with i_nlink == 2 (for "." entry) */
 		inode->i_nlink++;	
 	} else {

diff -Nru a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
@@ -20,6 +20,8 @@
 extern int sysfs_follow_link(struct dentry *, struct nameidata *);
 extern void sysfs_put_link(struct dentry *, struct nameidata *);
 extern struct rw_semaphore sysfs_rename_sem;
+extern struct super_block * sysfs_sb;
+extern struct file_operations sysfs_dir_operations;
 
 struct sysfs_symlink {
 	char * link_name;

diff -Nru a/fs/sysfs/bin.c b/fs/sysfs/bin.c
@@ -141,7 +141,7 @@
 	return 0;
 }
 
-static struct file_operations bin_fops = {
+struct file_operations bin_fops = {
 	.read		= read,
 	.write		= write,
 	.llseek		= generic_file_llseek,

@@ -158,33 +158,9 @@
 
 int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
 {
-	struct dentry * dentry;
-	struct dentry * parent;
-	umode_t mode = (attr->attr.mode & S_IALLUGO) | S_IFREG;
-	int error = 0;
-
 	BUG_ON(!kobj || !kobj->dentry || !attr);
 
-	parent = kobj->dentry;
-
-	down(&parent->d_inode->i_sem);
-	dentry = sysfs_get_dentry(parent,attr->attr.name);
-	if (!IS_ERR(dentry)) {
-		error = sysfs_create(dentry, mode, NULL);
-		if (!error) {
-			dentry->d_inode->i_size = attr->size;
-			dentry->d_inode->i_fop = &bin_fops;
-			error = sysfs_make_dirent(parent->d_fsdata, dentry,
-						  (void *) attr, mode,
-						  SYSFS_KOBJ_BIN_ATTR);
-		}
-		if (error)
-			d_drop(dentry);
-		dput(dentry);
-	} else
-		error = PTR_ERR(dentry);
-	up(&parent->d_inode->i_sem);
-	return error;
+	return sysfs_add_file(kobj->dentry, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
 }
 
 

150 lines not on this page · raw message

diff -Nru a/fs/sysfs/file.c b/fs/sysfs/file.c
@@ -9,15 +9,6 @@
 
 #include "sysfs.h"
 
-static struct file_operations sysfs_file_operations;
-
-static int init_file(struct inode * inode)
-{
-	inode->i_size = PAGE_SIZE;
-	inode->i_fop = &sysfs_file_operations;
-	return 0;
-}
-
 #define to_subsys(k) container_of(k,struct subsystem,kset.kobj)
 #define to_sattr(a) container_of(a,struct subsys_attribute,attr)
 

@@ -337,7 +328,7 @@
 	return 0;
 }
 
-static struct file_operations sysfs_file_operations = {
+struct file_operations sysfs_file_operations = {
 	.read		= sysfs_read_file,
 	.write		= sysfs_write_file,
 	.llseek		= generic_file_llseek,

@@ -348,24 +339,14 @@
 
 int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type)
 {
-	struct dentry * dentry;
 	struct sysfs_dirent * parent_sd = dir->d_fsdata;
 	umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
 	int error = 0;
 
 	down(&dir->d_inode->i_sem);
-	dentry = sysfs_get_dentry(dir,attr->name);
-	if (!IS_ERR(dentry)) {
-		error = sysfs_create(dentry, mode, init_file);
-		if (!error)
-			error = sysfs_make_dirent(parent_sd, dentry,
-						(void *) attr, mode, type);
-		if (error)
-			d_drop(dentry);
-		dput(dentry);
-	} else
-		error = PTR_ERR(dentry);
+	error = sysfs_make_dirent(parent_sd, NULL, (void *) attr, mode, type);
 	up(&dir->d_inode->i_sem);
+
 	return error;
 }
 

diff -Nru a/fs/sysfs/mount.c b/fs/sysfs/mount.c
@@ -42,7 +42,7 @@
 
 	inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO);
 	if (inode) {
-		inode->i_op = &simple_dir_inode_operations;
+		inode->i_op = &sysfs_dir_inode_operations;
 		inode->i_fop = &sysfs_dir_operations;
 		/* directory inodes start off with i_nlink == 2 (for "." entry) */
 		inode->i_nlink++;	

diff -Nru a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
@@ -9,18 +9,12 @@
 
 #include "sysfs.h"
 
-static struct inode_operations sysfs_symlink_inode_operations = {
+struct inode_operations sysfs_symlink_inode_operations = {
 	.readlink = generic_readlink,
 	.follow_link = sysfs_follow_link,
 	.put_link = sysfs_put_link,
 };
 
-static int init_symlink(struct inode * inode)
-{
-	inode->i_op = &sysfs_symlink_inode_operations;
-	return 0;
-}
-
 static int object_depth(struct kobject * kobj)
 {
 	struct kobject * p = kobj;

@@ -55,9 +49,9 @@
 	}
 }
 
-static int sysfs_add_link(struct dentry * dentry, char * name, struct kobject * target)
+static int sysfs_add_link(struct dentry * parent, char * name, struct kobject * target)
 {
-	struct sysfs_dirent * parent_sd = dentry->d_parent->d_fsdata;
+	struct sysfs_dirent * parent_sd = parent->d_fsdata;
 	struct sysfs_symlink * sl;
 	int error = 0;
 

@@ -73,7 +67,7 @@
 	strcpy(sl->link_name, name);
 	sl->target_kobj = kobject_get(target);
 
-	error = sysfs_make_dirent(parent_sd, dentry, sl, S_IFLNK|S_IRWXUGO,
+	error = sysfs_make_dirent(parent_sd, NULL, sl, S_IFLNK|S_IRWXUGO,
 				SYSFS_KOBJ_LINK);
 	if (!error)
 		return 0;

@@ -94,22 +88,12 @@
 int sysfs_create_link(struct kobject * kobj, struct kobject * target, char * name)
 {
 	struct dentry * dentry = kobj->dentry;
-	struct dentry * d;
 	int error = 0;
 
 	BUG_ON(!kobj || !kobj->dentry || !name);
 
 	down(&dentry->d_inode->i_sem);
-	d = sysfs_get_dentry(dentry,name);
-	if (!IS_ERR(d)) {
-		error = sysfs_create(d, S_IFLNK|S_IRWXUGO, init_symlink);
-		if (!error)
-			error = sysfs_add_link(d, name, target);
-		if (error)
-			d_drop(d);
-		dput(d);
-	} else 
-		error = PTR_ERR(d);
+	error = sysfs_add_link(dentry, name, target);
 	up(&dentry->d_inode->i_sem);
 	return error;
 }

diff -Nru a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
@@ -22,6 +22,10 @@
 extern struct rw_semaphore sysfs_rename_sem;
 extern struct super_block * sysfs_sb;
 extern struct file_operations sysfs_dir_operations;
+extern struct file_operations sysfs_file_operations;
+extern struct file_operations bin_fops;
+extern struct inode_operations sysfs_dir_inode_operations;
+extern struct inode_operations sysfs_symlink_inode_operations;
 
 struct sysfs_symlink {
 	char * link_name;

diff -Nru a/fs/sysfs/file.c b/fs/sysfs/file.c
@@ -6,6 +6,7 @@
 #include <linux/dnotify.h>
 #include <linux/kobject.h>
 #include <asm/uaccess.h>
+#include <asm/semaphore.h>
 
 #include "sysfs.h"
 

@@ -53,6 +54,7 @@
 	loff_t			pos;
 	char			* page;
 	struct sysfs_ops	* ops;
+	struct semaphore	sem;
 };
 
 

@@ -106,6 +108,9 @@
 {
 	int error;
 
+	if (*ppos > buffer->count)
+		return 0;
+
 	if (count > (buffer->count - *ppos))
 		count = buffer->count - *ppos;
 

@@ -140,13 +145,17 @@
 	struct sysfs_buffer * buffer = file->private_data;
 	ssize_t retval = 0;
 
-	if (!*ppos) {
+	down(&buffer->sem);
+	if ((!*ppos) || (!buffer->page)) {
 		if ((retval = fill_read_buffer(file->f_dentry,buffer)))
-			return retval;
+			goto out;
 	}
 	pr_debug("%s: count = %d, ppos = %lld, buf = %s\n",
 		 __FUNCTION__,count,*ppos,buffer->page);
-	return flush_read_buffer(buffer,buf,count,ppos);
+	retval = flush_read_buffer(buffer,buf,count,ppos);
+out:
+	up(&buffer->sem);
+	return retval;
 }
 
 

@@ -220,11 +229,13 @@
 {
 	struct sysfs_buffer * buffer = file->private_data;
 
+	down(&buffer->sem);
 	count = fill_write_buffer(buffer,buf,count);
 	if (count > 0)
 		count = flush_write_buffer(file->f_dentry,buffer,count);
 	if (count > 0)
 		*ppos += count;
+	up(&buffer->sem);
 	return count;
 }
 

@@ -287,6 +298,7 @@
 	buffer = kmalloc(sizeof(struct sysfs_buffer),GFP_KERNEL);
 	if (buffer) {
 		memset(buffer,0,sizeof(struct sysfs_buffer));
+		init_MUTEX(&buffer->sem);
 		buffer->ops = ops;
 		file->private_data = buffer;
 	} else

diff -Nru a/fs/sysfs/file.c b/fs/sysfs/file.c
@@ -55,6 +55,7 @@
 	char			* page;
 	struct sysfs_ops	* ops;
 	struct semaphore	sem;
+	int			needs_read_fill;
 };
 
 

@@ -82,6 +83,7 @@
 		return -ENOMEM;
 
 	count = ops->show(kobj,attr,buffer->page);
+	buffer->needs_read_fill = 0;
 	BUG_ON(count > (ssize_t)PAGE_SIZE);
 	if (count >= 0)
 		buffer->count = count;

@@ -146,7 +148,7 @@
 	ssize_t retval = 0;
 
 	down(&buffer->sem);
-	if ((!*ppos) || (!buffer->page)) {
+	if (buffer->needs_read_fill) {
 		if ((retval = fill_read_buffer(file->f_dentry,buffer)))
 			goto out;
 	}

@@ -182,6 +184,7 @@
 	if (count >= PAGE_SIZE)
 		count = PAGE_SIZE - 1;
 	error = copy_from_user(buffer->page,buf,count);
+	buffer->needs_read_fill = 1;
 	return error ? -EFAULT : count;
 }
 

@@ -299,6 +302,7 @@
 	if (buffer) {
 		memset(buffer,0,sizeof(struct sysfs_buffer));
 		init_MUTEX(&buffer->sem);
+		buffer->needs_read_fill = 1;
 		buffer->ops = ops;
 		file->private_data = buffer;
 	} else

diff -Nru a/drivers/base/power/main.c b/drivers/base/power/main.c
@@ -28,6 +28,7 @@
 LIST_HEAD(dpm_off_irq);
 
 DECLARE_MUTEX(dpm_sem);
+DECLARE_MUTEX(dpm_list_sem);
 
 /*
  * PM Reference Counting.

@@ -75,12 +76,12 @@
 	pr_debug("PM: Adding info for %s:%s\n",
 		 dev->bus ? dev->bus->name : "No Bus", dev->kobj.name);
 	atomic_set(&dev->power.pm_users, 0);
-	down(&dpm_sem);
+	down(&dpm_list_sem);
 	list_add_tail(&dev->power.entry, &dpm_active);
 	device_pm_set_parent(dev, dev->parent);
 	if ((error = dpm_sysfs_add(dev)))
 		list_del(&dev->power.entry);
-	up(&dpm_sem);
+	up(&dpm_list_sem);
 	return error;
 }
 

@@ -88,11 +89,11 @@
 {
 	pr_debug("PM: Removing info for %s:%s\n",
 		 dev->bus ? dev->bus->name : "No Bus", dev->kobj.name);
-	down(&dpm_sem);
+	down(&dpm_list_sem);
 	dpm_sysfs_remove(dev);
 	device_pm_release(dev->power.pm_parent);
-	list_del(&dev->power.entry);
-	up(&dpm_sem);
+	list_del_init(&dev->power.entry);
+	up(&dpm_list_sem);
 }
 
 

diff -Nru a/drivers/base/power/power.h b/drivers/base/power/power.h
@@ -28,6 +28,11 @@
 extern struct semaphore dpm_sem;
 
 /*
+ * Used to serialize changes to the dpm_* lists.
+ */
+extern struct semaphore dpm_list_sem;
+
+/*
  * The PM lists.
  */
 extern struct list_head dpm_active;

diff -Nru a/drivers/base/power/resume.c b/drivers/base/power/resume.c
@@ -31,16 +31,22 @@
 
 void dpm_resume(void)
 {
+	down(&dpm_list_sem);
 	while(!list_empty(&dpm_off)) {
 		struct list_head * entry = dpm_off.next;
 		struct device * dev = to_device(entry);
+
+		get_device(dev);
 		list_del_init(entry);
+		list_add_tail(entry, &dpm_active);
 
+		up(&dpm_list_sem);
 		if (!dev->power.prev_state)
 			resume_device(dev);
-
-		list_add_tail(entry, &dpm_active);
+		down(&dpm_list_sem);
+		put_device(dev);
 	}
+	up(&dpm_list_sem);
 }
 
 

@@ -76,9 +82,13 @@
 {
 	while(!list_empty(&dpm_off_irq)) {
 		struct list_head * entry = dpm_off_irq.next;
+		struct device * dev = to_device(entry);
+
+		get_device(dev);
 		list_del_init(entry);
-		resume_device(to_device(entry));
 		list_add_tail(entry, &dpm_active);
+		resume_device(dev);
+		put_device(dev);
 	}
 }
 

65 lines not on this page · raw message

diff -Nru a/drivers/base/bus.c b/drivers/base/bus.c
@@ -288,7 +288,7 @@
  *	Walk the list of drivers that the bus has and call bus_match()
  *	for each pair. If a compatible pair is found, break out and return.
  */
-static int device_attach(struct device * dev)
+int device_attach(struct device * dev)
 {
  	struct bus_type * bus = dev->bus;
 	struct list_head * entry;

@@ -728,6 +728,8 @@
 
 EXPORT_SYMBOL_GPL(device_bind_driver);
 EXPORT_SYMBOL_GPL(device_release_driver);
+EXPORT_SYMBOL_GPL(device_attach);
+EXPORT_SYMBOL_GPL(driver_attach);
 
 EXPORT_SYMBOL_GPL(bus_add_device);
 EXPORT_SYMBOL_GPL(bus_remove_device);

diff -Nru a/include/linux/device.h b/include/linux/device.h
@@ -327,6 +327,7 @@
  */
 extern void device_bind_driver(struct device * dev);
 extern void device_release_driver(struct device * dev);
+extern int  device_attach(struct device * dev);
 extern void driver_attach(struct device_driver * drv);
 
 

diff -Nru a/drivers/base/bus.c b/drivers/base/bus.c
@@ -250,34 +250,35 @@
 
 
 /**
- *	bus_match - check compatibility between device & driver.
- *	@dev:	device.
+ *	driver_probe_device - attempt to bind device & driver.
  *	@drv:	driver.
+ *	@dev:	device.
  *
- *	First, we call the bus's match function, which should compare
- *	the device IDs the driver supports with the device IDs of the
- *	device. Note we don't do this ourselves because we don't know
- *	the format of the ID structures, nor what is to be considered
- *	a match and what is not.
+ *	First, we call the bus's match function, if one present, which
+ *	should compare the device IDs the driver supports with the
+ *	device IDs of the device. Note we don't do this ourselves
+ *	because we don't know the format of the ID structures, nor what
+ *	is to be considered a match and what is not.
  *
  *	If we find a match, we call @drv->probe(@dev) if it exists, and
- *	call attach() above.
+ *	call device_bind_driver() above.
  */
-static int bus_match(struct device * dev, struct device_driver * drv)
+int driver_probe_device(struct device_driver * drv, struct device * dev)
 {
-	int error = -ENODEV;
-	if (dev->bus->match(dev, drv)) {
-		dev->driver = drv;
-		if (drv->probe) {
-			if ((error = drv->probe(dev))) {
-				dev->driver = NULL;
-				return error;
-			}
+	if (drv->bus->match && !drv->bus->match(dev, drv))
+		return -ENODEV;
+
+	dev->driver = drv;
+	if (drv->probe) {
+		int error = drv->probe(dev);
+		if (error) {
+			dev->driver = NULL;
+			return error;
 		}
-		device_bind_driver(dev);
-		error = 0;
 	}
-	return error;
+
+	device_bind_driver(dev);
+	return 0;
 }
 
 

@@ -285,8 +286,9 @@
  *	device_attach - try to attach device to a driver.
  *	@dev:	device.
  *
- *	Walk the list of drivers that the bus has and call bus_match()
- *	for each pair. If a compatible pair is found, break out and return.
+ *	Walk the list of drivers that the bus has and call
+ *	driver_probe_device() for each pair. If a compatible
+ *	pair is found, break out and return.
  */
 int device_attach(struct device * dev)
 {

@@ -302,7 +304,7 @@
 	if (bus->match) {
 		list_for_each(entry, &bus->drivers.list) {
 			struct device_driver * drv = to_drv(entry);
-			error = bus_match(dev, drv);
+			error = driver_probe_device(drv, dev);
 			if (!error)
 				/* success, driver matched */
 				return 1;

@@ -327,8 +329,8 @@
  *	If bus_match() returns 0 and the @dev->driver is set, we've found
  *	a compatible pair.
  *
- *	Note that we ignore the -ENODEV error from bus_match(), since it's
- *	perfectly valid for a driver not to bind to any devices.
+ *	Note that we ignore the -ENODEV error from driver_probe_device(),
+ *	since it's perfectly valid for a driver not to bind to any devices.
  */
 void driver_attach(struct device_driver * drv)
 {

@@ -342,7 +344,7 @@
 	list_for_each(entry, &bus->devices.list) {
 		struct device * dev = container_of(entry, struct device, bus_list);
 		if (!dev->driver) {
-			error = bus_match(dev, drv);
+			error = driver_probe_device(drv, dev);
 			if (error && (error != -ENODEV))
 				/* driver matched but the probe failed */
 				printk(KERN_WARNING

@@ -726,6 +728,7 @@
 EXPORT_SYMBOL_GPL(bus_for_each_dev);
 EXPORT_SYMBOL_GPL(bus_for_each_drv);
 
+EXPORT_SYMBOL_GPL(driver_probe_device);
 EXPORT_SYMBOL_GPL(device_bind_driver);
 EXPORT_SYMBOL_GPL(device_release_driver);
 EXPORT_SYMBOL_GPL(device_attach);

diff -Nru a/include/linux/device.h b/include/linux/device.h
@@ -322,9 +322,10 @@
 		     int (*fn)(struct device *, void *));
 
 /*
- * Manual binding of a device to driver. See drivers/base/bus.c 
+ * Manual binding of a device to driver. See drivers/base/bus.c
  * for information on use.
  */
+extern int  driver_probe_device(struct device_driver * drv, struct device * dev);
 extern void device_bind_driver(struct device * dev);
 extern void device_release_driver(struct device * dev);
 extern int  device_attach(struct device * dev);

diff -Nru a/lib/kobject_uevent.c b/lib/kobject_uevent.c
@@ -23,6 +23,9 @@
 #include <linux/kobject.h>
 #include <net/sock.h>
 
+#define BUFFER_SIZE	1024	/* buffer for the hotplug env */
+#define NUM_ENVP	32	/* number of env pointers */
+
 #if defined(CONFIG_KOBJECT_UEVENT) || defined(CONFIG_HOTPLUG)
 static char *action_to_string(enum kobject_action action)
 {

@@ -53,12 +56,11 @@
  *
  * @signal: signal name
  * @obj: object path (kobject)
- * @buf: buffer used to pass auxiliary data like the hotplug environment
- * @buflen:
- * gfp_mask:
+ * @envp: possible hotplug environment to pass with the message
+ * @gfp_mask:
  */
-static int send_uevent(const char *signal, const char *obj, const void *buf,
-			int buflen, int gfp_mask)
+static int send_uevent(const char *signal, const char *obj,
+		       char **envp, int gfp_mask)
 {
 	struct sk_buff *skb;
 	char *pos;

@@ -69,16 +71,25 @@
 
 	len = strlen(signal) + 1;
 	len += strlen(obj) + 1;
-	len += buflen;
 
-	skb = alloc_skb(len, gfp_mask);
+	/* allocate buffer with the maximum possible message size */
+	skb = alloc_skb(len + BUFFER_SIZE, gfp_mask);
 	if (!skb)
 		return -ENOMEM;
 
 	pos = skb_put(skb, len);
+	sprintf(pos, "%s@%s", signal, obj);
 
-	pos += sprintf(pos, "%s@%s", signal, obj) + 1;
-	memcpy(pos, buf, buflen);
+	/* copy the environment key by key to our continuous buffer */
+	if (envp) {
+		int i;
+
+		for (i = 2; envp[i]; i++) {
+			len = strlen(envp[i]) + 1;
+			pos = skb_put(skb, len);
+			strcpy(pos, envp[i]);
+		}
+	}
 
 	return netlink_broadcast(uevent_sock, skb, 0, 1, gfp_mask);
 }

@@ -107,10 +118,10 @@
 		if (!attrpath)
 			goto exit;
 		sprintf(attrpath, "%s/%s", path, attr->name);
-		rc = send_uevent(signal, attrpath, NULL, 0, gfp_mask);
+		rc = send_uevent(signal, attrpath, NULL, gfp_mask);
 		kfree(attrpath);
 	} else {
-		rc = send_uevent(signal, path, NULL, 0, gfp_mask);
+		rc = send_uevent(signal, path, NULL, gfp_mask);
 	}
 
 exit:

@@ -169,8 +180,6 @@
 u64 hotplug_seqnum;
 static spinlock_t sequence_lock = SPIN_LOCK_UNLOCKED;
 
-#define BUFFER_SIZE	1024	/* should be enough memory for the env */
-#define NUM_ENVP	32	/* number of env pointers */
 /**
  * kobject_hotplug - notify userspace by executing /sbin/hotplug
  *

@@ -182,6 +191,7 @@
 	char *argv [3];
 	char **envp = NULL;
 	char *buffer = NULL;
+	char *seq_buff;
 	char *scratch;
 	int i = 0;
 	int retval;

@@ -258,6 +268,11 @@
 	envp [i++] = scratch;
 	scratch += sprintf(scratch, "SUBSYSTEM=%s", name) + 1;
 
+	/* reserve space for the sequence,
+	 * put the real one in after the hotplug call */
+	envp[i++] = seq_buff = scratch;
+	scratch += strlen("SEQNUM=18446744073709551616") + 1;
+
 	if (hotplug_ops->hotplug) {
 		/* have the kset specific function add its stuff */
 		retval = hotplug_ops->hotplug (kset, kobj,

@@ -273,15 +288,13 @@
 	spin_lock(&sequence_lock);
 	seq = ++hotplug_seqnum;
 	spin_unlock(&sequence_lock);
-
-	envp [i++] = scratch;
-	scratch += sprintf(scratch, "SEQNUM=%lld", (long long)seq) + 1;
+	sprintf(seq_buff, "SEQNUM=%lld", (long long)seq);
 
 	pr_debug ("%s: %s %s seq=%lld %s %s %s %s %s\n",
 		  __FUNCTION__, argv[0], argv[1], (long long)seq,
 		  envp[0], envp[1], envp[2], envp[3], envp[4]);
 
-	send_uevent(action_string, kobj_path, buffer, scratch - buffer, GFP_KERNEL);
+	send_uevent(action_string, kobj_path, envp, GFP_KERNEL);
 
 	if (!hotplug_path[0])
 		goto exit;

diff -Nru a/drivers/base/bus.c b/drivers/base/bus.c
@@ -246,6 +246,7 @@
 	list_add_tail(&dev->driver_list, &dev->driver->devices);
 	sysfs_create_link(&dev->driver->kobj, &dev->kobj,
 			  kobject_name(&dev->kobj));
+	sysfs_create_link(&dev->kobj, &dev->driver->kobj, "driver");
 }
 
 

@@ -370,6 +371,7 @@
 	struct device_driver * drv = dev->driver;
 	if (drv) {
 		sysfs_remove_link(&drv->kobj, kobject_name(&dev->kobj));
+		sysfs_remove_link(&dev->kobj, "driver");
 		list_del_init(&dev->driver_list);
 		device_detach_shutdown(dev);
 		if (drv->remove)

diff -Nru a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
@@ -246,11 +246,6 @@
 	return sprintf(buf, "%s\n", serio->name);
 }
 
-static ssize_t serio_show_driver(struct device *dev, char *buf)
-{
-	return sprintf(buf, "%s\n", dev->driver ? dev->driver->name : "(none)");
-}
-
 static ssize_t serio_rebind_driver(struct device *dev, const char *buf, size_t count)
 {
 	struct serio *serio = to_serio_port(dev);

@@ -307,7 +302,7 @@
 
 static struct device_attribute serio_device_attrs[] = {
 	__ATTR(description, S_IRUGO, serio_show_description, NULL),
-	__ATTR(driver, S_IWUSR | S_IRUGO, serio_show_driver, serio_rebind_driver),
+	__ATTR(drvctl, S_IWUSR, NULL, serio_rebind_driver),
 	__ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode),
 	__ATTR_NULL
 };

diff -Nru a/drivers/input/input.c b/drivers/input/input.c
@@ -19,7 +19,7 @@
 #include <linux/major.h>
 #include <linux/pm.h>
 #include <linux/proc_fs.h>
-#include <linux/kmod.h>
+#include <linux/kobject_uevent.h>
 #include <linux/interrupt.h>
 #include <linux/poll.h>
 #include <linux/device.h>

diff -Nru a/drivers/pnp/pnpbios/core.c b/drivers/pnp/pnpbios/core.c
@@ -56,7 +56,7 @@
 #include <linux/mm.h>
 #include <linux/smp.h>
 #include <linux/slab.h>
-#include <linux/kmod.h>
+#include <linux/kobject_uevent.h>
 #include <linux/completion.h>
 #include <linux/spinlock.h>
 #include <linux/dmi.h>

diff -Nru a/drivers/s390/crypto/z90main.c b/drivers/s390/crypto/z90main.c
@@ -33,6 +33,7 @@
 #include <linux/ioctl32.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/kobject_uevent.h>
 #include <linux/proc_fs.h>
 #include <linux/syscalls.h>
 #include <linux/version.h>

diff -Nru a/include/linux/kmod.h b/include/linux/kmod.h
@@ -37,8 +37,4 @@
 extern int call_usermodehelper(char *path, char *argv[], char *envp[], int wait);
 extern void usermodehelper_init(void);
 
-#ifdef CONFIG_HOTPLUG
-extern char hotplug_path [];
-#endif
-
 #endif /* __LINUX_KMOD_H__ */

diff -Nru a/include/linux/kobject_uevent.h b/include/linux/kobject_uevent.h
@@ -11,6 +11,11 @@
 #ifndef _KOBJECT_EVENT_H_
 #define _KOBJECT_EVENT_H_
 
+#define HOTPLUG_PATH_LEN	256
+
+/* path to the hotplug userspace helper executed on an event */
+extern char hotplug_path[];
+
 /*
  * If you add an action here, you must also add the proper string to the
  * lib/kobject_uevent.c file.

diff -Nru a/kernel/cpu.c b/kernel/cpu.c
@@ -11,7 +11,6 @@
 #include <linux/unistd.h>
 #include <linux/cpu.h>
 #include <linux/module.h>
-#include <linux/kmod.h>		/* for hotplug_path */
 #include <linux/kthread.h>
 #include <linux/stop_machine.h>
 #include <asm/semaphore.h>

diff -Nru a/kernel/kmod.c b/kernel/kmod.c
@@ -115,29 +115,6 @@
 EXPORT_SYMBOL(request_module);
 #endif /* CONFIG_KMOD */
 
-#ifdef CONFIG_HOTPLUG
-/*
-	hotplug path is set via /proc/sys
-	invoked by hotplug-aware bus drivers,
-	with call_usermodehelper
-
-	argv [0] = hotplug_path;
-	argv [1] = "usb", "scsi", "pci", "network", etc;
-	... plus optional type-specific parameters
-	argv [n] = 0;
-
-	envp [*] = HOME, PATH; optional type-specific parameters
-
-	a hotplug bus should invoke this for device add/remove
-	events.  the command is expected to load drivers when
-	necessary, and may perform additional system setup.
-*/
-char hotplug_path[KMOD_PATH_LEN] = "/sbin/hotplug";
-
-EXPORT_SYMBOL(hotplug_path);
-
-#endif /* CONFIG_HOTPLUG */
-
 struct subprocess_info {
 	struct completion *complete;
 	char *path;

diff -Nru a/kernel/sysctl.c b/kernel/sysctl.c
@@ -394,7 +394,7 @@
 		.ctl_name	= KERN_HOTPLUG,
 		.procname	= "hotplug",
 		.data		= &hotplug_path,
-		.maxlen		= KMOD_PATH_LEN,
+		.maxlen		= HOTPLUG_PATH_LEN,
 		.mode		= 0644,
 		.proc_handler	= &proc_dostring,
 		.strategy	= &sysctl_string,

diff -Nru a/lib/kobject_uevent.c b/lib/kobject_uevent.c
@@ -177,6 +177,7 @@
 
 
 #ifdef CONFIG_HOTPLUG
+char hotplug_path[HOTPLUG_PATH_LEN] = "/sbin/hotplug";
 u64 hotplug_seqnum;
 static spinlock_t sequence_lock = SPIN_LOCK_UNLOCKED;