X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fsysfs%2Fsymlink.c;h=d2eac3ceed5f31cf9735a68ecc69dc4a6c6771ed;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=3169fe516e6f6c21b8dc61e6596ba1fbe3ad0f30;hpb=c7b5ebbddf7bcd3651947760f423e3783bbe6573;p=linux-2.6.git

diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index 3169fe516..d2eac3cee 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -9,18 +9,6 @@
 
 #include "sysfs.h"
 
-static 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;
@@ -55,31 +43,54 @@ static void fill_object_path(struct kobject * kobj, char * buffer, int length)
 	}
 }
 
+static int sysfs_add_link(struct dentry * parent, const char * name, struct kobject * target)
+{
+	struct sysfs_dirent * parent_sd = 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, NULL, sl, S_IFLNK|S_IRWXUGO,
+				SYSFS_KOBJ_LINK);
+	if (!error)
+		return 0;
+
+	kobject_put(target);
+	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.
  *	@target:	object we're pointing to.
  *	@name:		name of the symlink.
  */
-int sysfs_create_link(struct kobject * kobj, struct kobject * target, char * name)
+int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char * name)
 {
 	struct dentry * dentry = kobj->dentry;
-	struct dentry * d;
-	int error = 0;
+	int error = -EEXIST;
+
+	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);
-		dput(d);
-	} else 
-		error = PTR_ERR(d);
-	up(&dentry->d_inode->i_sem);
+	mutex_lock(&dentry->d_inode->i_mutex);
+	if (!sysfs_dirent_exist(dentry->d_fsdata, name))
+		error = sysfs_add_link(dentry, name, target);
+	mutex_unlock(&dentry->d_inode->i_mutex);
 	return error;
 }
 
@@ -90,13 +101,13 @@ int sysfs_create_link(struct kobject * kobj, struct kobject * target, char * nam
  *	@name:	name of the symlink to remove.
  */
 
-void sysfs_remove_link(struct kobject * kobj, char * name)
+void sysfs_remove_link(struct kobject * kobj, const char * name)
 {
 	sysfs_hash_and_remove(kobj->dentry,name);
 }
 
 static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target,
-				   char *path)
+				 char *path)
 {
 	char * s;
 	int depth, size;
@@ -142,23 +153,29 @@ static int sysfs_getlink(struct dentry *dentry, char * path)
 
 }
 
-int sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
 	int error = -ENOMEM;
 	unsigned long page = get_zeroed_page(GFP_KERNEL);
 	if (page)
 		error = sysfs_getlink(dentry, (char *) page); 
 	nd_set_link(nd, error ? ERR_PTR(error) : (char *)page);
-	return 0;
+	return NULL;
 }
 
-void sysfs_put_link(struct dentry *dentry, struct nameidata *nd)
+static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
 {
 	char *page = nd_get_link(nd);
 	if (!IS_ERR(page))
 		free_page((unsigned long)page);
 }
 
-EXPORT_SYMBOL(sysfs_create_link);
-EXPORT_SYMBOL(sysfs_remove_link);
+struct inode_operations sysfs_symlink_inode_operations = {
+	.readlink = generic_readlink,
+	.follow_link = sysfs_follow_link,
+	.put_link = sysfs_put_link,
+};
+
 
+EXPORT_SYMBOL_GPL(sysfs_create_link);
+EXPORT_SYMBOL_GPL(sysfs_remove_link);