diff options
Diffstat (limited to 'fs/sysfs/symlink.c')
-rw-r--r-- | fs/sysfs/symlink.c | 137 |
1 files changed, 0 insertions, 137 deletions
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index b137aa3a486..6797c9c2e43 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -11,53 +11,13 @@ */ #include <linux/fs.h> -#include <linux/gfp.h> -#include <linux/mount.h> #include <linux/module.h> #include <linux/kobject.h> -#include <linux/namei.h> #include <linux/mutex.h> #include <linux/security.h> #include "sysfs.h" -/** - * kernfs_create_link - create a symlink - * @parent: directory to create the symlink in - * @name: name of the symlink - * @target: target node for the symlink to point to - * - * Returns the created node on success, ERR_PTR() value on error. - */ -struct sysfs_dirent *kernfs_create_link(struct sysfs_dirent *parent, - const char *name, - struct sysfs_dirent *target) -{ - struct sysfs_dirent *sd; - struct sysfs_addrm_cxt acxt; - int error; - - sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK); - if (!sd) - return ERR_PTR(-ENOMEM); - - if (parent->s_flags & SYSFS_FLAG_NS) - sd->s_ns = target->s_ns; - sd->s_symlink.target_sd = target; - kernfs_get(target); /* ref owned by symlink */ - - sysfs_addrm_start(&acxt); - error = sysfs_add_one(&acxt, sd, parent); - sysfs_addrm_finish(&acxt); - - if (!error) - return sd; - - kernfs_put(sd); - return ERR_PTR(error); -} - - static int sysfs_do_create_link_sd(struct sysfs_dirent *parent_sd, struct kobject *target, const char *name, int warn) @@ -235,100 +195,3 @@ out: return result; } EXPORT_SYMBOL_GPL(sysfs_rename_link_ns); - -static int sysfs_get_target_path(struct sysfs_dirent *parent_sd, - struct sysfs_dirent *target_sd, char *path) -{ - struct sysfs_dirent *base, *sd; - char *s = path; - int len = 0; - - /* go up to the root, stop at the base */ - base = parent_sd; - while (base->s_parent) { - sd = target_sd->s_parent; - while (sd->s_parent && base != sd) - sd = sd->s_parent; - - if (base == sd) - break; - - strcpy(s, "../"); - s += 3; - base = base->s_parent; - } - - /* determine end of target string for reverse fillup */ - sd = target_sd; - while (sd->s_parent && sd != base) { - len += strlen(sd->s_name) + 1; - sd = sd->s_parent; - } - - /* check limits */ - if (len < 2) - return -EINVAL; - len--; - if ((s - path) + len > PATH_MAX) - return -ENAMETOOLONG; - - /* reverse fillup of target string from target to base */ - sd = target_sd; - while (sd->s_parent && sd != base) { - int slen = strlen(sd->s_name); - - len -= slen; - strncpy(s + len, sd->s_name, slen); - if (len) - s[--len] = '/'; - - sd = sd->s_parent; - } - - return 0; -} - -static int sysfs_getlink(struct dentry *dentry, char *path) -{ - struct sysfs_dirent *sd = dentry->d_fsdata; - struct sysfs_dirent *parent_sd = sd->s_parent; - struct sysfs_dirent *target_sd = sd->s_symlink.target_sd; - int error; - - mutex_lock(&sysfs_mutex); - error = sysfs_get_target_path(parent_sd, target_sd, path); - mutex_unlock(&sysfs_mutex); - - return error; -} - -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); - if (error < 0) - free_page((unsigned long)page); - } - nd_set_link(nd, error ? ERR_PTR(error) : (char *)page); - return NULL; -} - -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); -} - -const struct inode_operations sysfs_symlink_inode_operations = { - .setxattr = sysfs_setxattr, - .readlink = generic_readlink, - .follow_link = sysfs_follow_link, - .put_link = sysfs_put_link, - .setattr = sysfs_setattr, - .getattr = sysfs_getattr, - .permission = sysfs_permission, -}; |