X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fsysfs%2Fsymlink.c;h=dfdf70174354097df7f0924d3ff871dec48fb1c2;hb=6a77f38946aaee1cd85eeec6cf4229b204c15071;hp=c8bfec6b74286a1d9a318d74f43218b946b8b8d9;hpb=9213980e6a70d8473e0ffd4b39ab5b6caaba9ff5;p=linux-2.6.git diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index c8bfec6b7..dfdf70174 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -5,20 +5,10 @@ #include #include #include +#include #include "sysfs.h" -static struct inode_operations sysfs_symlink_inode_operations = { - .readlink = sysfs_readlink, - .follow_link = sysfs_follow_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; @@ -53,6 +43,36 @@ static void fill_object_path(struct kobject * kobj, char * buffer, int length) } } +static int sysfs_add_link(struct dentry * parent, 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; + + 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. @@ -62,21 +82,12 @@ static void fill_object_path(struct kobject * kobj, char * buffer, int length) 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) - /* - * associate the link dentry with the target kobject - */ - d->d_fsdata = kobject_get(target); - dput(d); - } else - error = PTR_ERR(d); + error = sysfs_add_link(dentry, name, target); up(&dentry->d_inode->i_sem); return error; } @@ -140,40 +151,30 @@ static int sysfs_getlink(struct dentry *dentry, char * path) } -int sysfs_readlink(struct dentry *dentry, char __user *buffer, int buflen) +static int sysfs_follow_link(struct dentry *dentry, struct nameidata *nd) { - int error = 0; + int error = -ENOMEM; unsigned long page = get_zeroed_page(GFP_KERNEL); - - if (!page) - return -ENOMEM; - - error = sysfs_getlink(dentry, (char *) page); - if (!error) - error = vfs_readlink(dentry, buffer, buflen, (char *) page); - - free_page(page); - - return error; + if (page) + error = sysfs_getlink(dentry, (char *) page); + nd_set_link(nd, error ? ERR_PTR(error) : (char *)page); + return 0; } -int sysfs_follow_link(struct dentry *dentry, struct nameidata *nd) +static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd) { - int error = 0; - unsigned long page = get_zeroed_page(GFP_KERNEL); - - if (!page) - return -ENOMEM; - - error = sysfs_getlink(dentry, (char *) page); - if (!error) - error = vfs_follow_link(nd, (char *) page); + char *page = nd_get_link(nd); + if (!IS_ERR(page)) + free_page((unsigned long)page); +} - free_page(page); +struct inode_operations sysfs_symlink_inode_operations = { + .readlink = generic_readlink, + .follow_link = sysfs_follow_link, + .put_link = sysfs_put_link, +}; - return error; -} -EXPORT_SYMBOL(sysfs_create_link); -EXPORT_SYMBOL(sysfs_remove_link); +EXPORT_SYMBOL_GPL(sysfs_create_link); +EXPORT_SYMBOL_GPL(sysfs_remove_link);