don't pass nameidata to ->follow_link()

its only use is getting passed to nd_jump_link(), which can obtain
it from current->nameidata
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Documentation/filesystems/Locking

@@ -50,7 +50,7 @@ prototypes:
 	int (*rename2) (struct inode *, struct dentry *,
 			struct inode *, struct dentry *, unsigned int);
 	int (*readlink) (struct dentry *, char __user *,int);
-	const char *(*follow_link) (struct dentry *, void **, struct nameidata *);
+	const char *(*follow_link) (struct dentry *, void **);
 	void (*put_link) (struct dentry *, void *);
 	void (*truncate) (struct inode *);
 	int (*permission) (struct inode *, int, unsigned int);

Documentation/filesystems/vfs.txt

@@ -350,7 +350,7 @@ struct inode_operations {
 	int (*rename2) (struct inode *, struct dentry *,
 			struct inode *, struct dentry *, unsigned int);
 	int (*readlink) (struct dentry *, char __user *,int);
-	const char *(*follow_link) (struct dentry *, void **, struct nameidata *);
+	const char *(*follow_link) (struct dentry *, void **);
 	void (*put_link) (struct dentry *, void *);
 	int (*permission) (struct inode *, int);
 	int (*get_acl)(struct inode *, int);

drivers/staging/lustre/lustre/llite/symlink.c

@@ -118,7 +118,7 @@ static int ll_readlink_internal(struct inode *inode,
 	return rc;
 }
 
-static const char *ll_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *ll_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct inode *inode = d_inode(dentry);
 	struct ptlrpc_request *request = NULL;

fs/9p/vfs_inode.c

@@ -1230,7 +1230,7 @@ ino_t v9fs_qid2ino(struct p9_qid *qid)
  *
  */
 
-static const char *v9fs_vfs_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *v9fs_vfs_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct v9fs_session_info *v9ses = v9fs_dentry2v9ses(dentry);
 	struct p9_fid *fid = v9fs_fid_lookup(dentry);

fs/9p/vfs_inode_dotl.c

@@ -910,7 +910,7 @@ v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
  */
 
 static const char *
-v9fs_vfs_follow_link_dotl(struct dentry *dentry, void **cookie, struct nameidata *nd)
+v9fs_vfs_follow_link_dotl(struct dentry *dentry, void **cookie)
 {
 	struct p9_fid *fid = v9fs_fid_lookup(dentry);
 	char *target;

fs/autofs4/symlink.c

@@ -12,7 +12,7 @@
 
 #include "autofs_i.h"
 
-static const char *autofs4_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *autofs4_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);

fs/befs/linuxvfs.c

@@ -42,7 +42,7 @@ static struct inode *befs_iget(struct super_block *, unsigned long);
 static struct inode *befs_alloc_inode(struct super_block *sb);
 static void befs_destroy_inode(struct inode *inode);
 static void befs_destroy_inodecache(void);
-static const char *befs_follow_link(struct dentry *, void **, struct nameidata *nd);
+static const char *befs_follow_link(struct dentry *, void **);
 static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
 			char **out, int *out_len);
 static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
@@ -464,7 +464,7 @@ befs_destroy_inodecache(void)
  * flag is set.
  */
 static const char *
-befs_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+befs_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct super_block *sb = dentry->d_sb;
 	struct befs_inode_info *befs_ino = BEFS_I(d_inode(dentry));

fs/cifs/cifsfs.h

@@ -120,7 +120,7 @@ extern struct vfsmount *cifs_dfs_d_automount(struct path *path);
 #endif
 
 /* Functions related to symlinks */
-extern const char *cifs_follow_link(struct dentry *direntry, void **cookie, struct nameidata *nd);
+extern const char *cifs_follow_link(struct dentry *direntry, void **cookie);
 extern int cifs_readlink(struct dentry *direntry, char __user *buffer,
 			 int buflen);
 extern int cifs_symlink(struct inode *inode, struct dentry *direntry,

fs/cifs/link.c

@@ -627,7 +627,7 @@ cifs_hardlink(struct dentry *old_file, struct inode *inode,
 }
 
 const char *
-cifs_follow_link(struct dentry *direntry, void **cookie, struct nameidata *nd)
+cifs_follow_link(struct dentry *direntry, void **cookie)
 {
 	struct inode *inode = d_inode(direntry);
 	int rc = -ENOMEM;

fs/configfs/symlink.c

@@ -279,7 +279,7 @@ static int configfs_getlink(struct dentry *dentry, char * path)
 
 }
 
-static const char *configfs_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *configfs_follow_link(struct dentry *dentry, void **cookie)
 {
 	unsigned long page = get_zeroed_page(GFP_KERNEL);
 	int error;

fs/ecryptfs/inode.c

@@ -675,7 +675,7 @@ static char *ecryptfs_readlink_lower(struct dentry *dentry, size_t *bufsiz)
 	return rc ? ERR_PTR(rc) : buf;
 }
 
-static const char *ecryptfs_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *ecryptfs_follow_link(struct dentry *dentry, void **cookie)
 {
 	size_t len;
 	char *buf = ecryptfs_readlink_lower(dentry, &len);

fs/ext4/symlink.c

@@ -23,7 +23,7 @@
 #include "xattr.h"
 
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-static const char *ext4_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *ext4_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct page *cpage = NULL;
 	char *caddr, *paddr = NULL;

fs/f2fs/namei.c

@@ -296,9 +296,9 @@ static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
 	return err;
 }
 
-static const char *f2fs_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *f2fs_follow_link(struct dentry *dentry, void **cookie)
 {
-	const char *link = page_follow_link_light(dentry, cookie, nd);
+	const char *link = page_follow_link_light(dentry, cookie);
 	if (!IS_ERR(link) && !*link) {
 		/* this is broken symlink case */
 		page_put_link(dentry, *cookie);

fs/fuse/dir.c

@@ -1365,7 +1365,7 @@ static int fuse_readdir(struct file *file, struct dir_context *ctx)
 	return err;
 }
 
-static const char *fuse_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *fuse_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct inode *inode = d_inode(dentry);
 	struct fuse_conn *fc = get_fuse_conn(inode);

fs/gfs2/inode.c

@@ -1548,7 +1548,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
  * Returns: 0 on success or error code
  */
 
-static const char *gfs2_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *gfs2_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct gfs2_inode *ip = GFS2_I(d_inode(dentry));
 	struct gfs2_holder i_gh;

fs/hostfs/hostfs_kern.c

@@ -892,7 +892,7 @@ static const struct inode_operations hostfs_dir_iops = {
 	.setattr	= hostfs_setattr,
 };
 
-static const char *hostfs_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *hostfs_follow_link(struct dentry *dentry, void **cookie)
 {
 	char *link = __getname();
 	if (link) {

fs/hppfs/hppfs.c

@@ -642,11 +642,11 @@ static int hppfs_readlink(struct dentry *dentry, char __user *buffer,
 						    buflen);
 }
 
-static const char *hppfs_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *hppfs_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct dentry *proc_dentry = HPPFS_I(d_inode(dentry))->proc_dentry;
 
-	return d_inode(proc_dentry)->i_op->follow_link(proc_dentry, cookie, nd);
+	return d_inode(proc_dentry)->i_op->follow_link(proc_dentry, cookie);
 }
 
 static void hppfs_put_link(struct dentry *dentry, void *cookie)

fs/kernfs/symlink.c

@@ -112,7 +112,7 @@ static int kernfs_getlink(struct dentry *dentry, char *path)
 	return error;
 }
 
-static const char *kernfs_iop_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *kernfs_iop_follow_link(struct dentry *dentry, void **cookie)
 {
 	int error = -ENOMEM;
 	unsigned long page = get_zeroed_page(GFP_KERNEL);

fs/libfs.c

@@ -1091,7 +1091,7 @@ simple_nosetlease(struct file *filp, long arg, struct file_lock **flp,
 }
 EXPORT_SYMBOL(simple_nosetlease);
 
-const char *simple_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+const char *simple_follow_link(struct dentry *dentry, void **cookie)
 {
 	return d_inode(dentry)->i_link;
 }

fs/namei.c

@@ -753,8 +753,9 @@ static inline void path_to_nameidata(const struct path *path,
  * Helper to directly jump to a known parsed path from ->follow_link,
  * caller must have taken a reference to path beforehand.
  */
-void nd_jump_link(struct nameidata *nd, struct path *path)
+void nd_jump_link(struct path *path)
 {
+	struct nameidata *nd = current->nameidata;
 	path_put(&nd->path);
 
 	nd->path = *path;
@@ -916,7 +917,7 @@ const char *get_link(struct nameidata *nd)
 	nd->last_type = LAST_BIND;
 	res = inode->i_link;
 	if (!res) {
-		res = inode->i_op->follow_link(dentry, &last->cookie, nd);
+		res = inode->i_op->follow_link(dentry, &last->cookie);
 		if (IS_ERR(res)) {
 out:
 			path_put(&last->link);
@@ -4485,12 +4486,12 @@ int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 	int res;
 
 	if (!link) {
-		link = dentry->d_inode->i_op->follow_link(dentry, &cookie, NULL);
+		link = dentry->d_inode->i_op->follow_link(dentry, &cookie);
 		if (IS_ERR(link))
 			return PTR_ERR(link);
 	}
 	res = readlink_copy(buffer, buflen, link);
-	if (cookie && dentry->d_inode->i_op->put_link)
+	if (dentry->d_inode->i_op->put_link)
 		dentry->d_inode->i_op->put_link(dentry, cookie);
 	return res;
 }
@@ -4523,7 +4524,7 @@ int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 }
 EXPORT_SYMBOL(page_readlink);
 
-const char *page_follow_link_light(struct dentry *dentry, void **cookie, struct nameidata *nd)
+const char *page_follow_link_light(struct dentry *dentry, void **cookie)
 {
 	struct page *page = NULL;
 	char *res = page_getlink(dentry, &page);

fs/nfs/symlink.c

@@ -42,7 +42,7 @@ static int nfs_symlink_filler(struct inode *inode, struct page *page)
 	return -EIO;
 }
 
-static const char *nfs_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *nfs_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct inode *inode = d_inode(dentry);
 	struct page *page;

fs/overlayfs/inode.c

@@ -140,7 +140,7 @@ struct ovl_link_data {
 	void *cookie;
 };
 
-static const char *ovl_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *ovl_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct dentry *realdentry;
 	struct inode *realinode;
@@ -160,7 +160,7 @@ static const char *ovl_follow_link(struct dentry *dentry, void **cookie, struct
 		data->realdentry = realdentry;
 	}
 
-	ret = realinode->i_op->follow_link(realdentry, cookie, nd);
+	ret = realinode->i_op->follow_link(realdentry, cookie);
 	if (IS_ERR_OR_NULL(ret)) {
 		kfree(data);
 		return ret;

fs/proc/base.c

@@ -1380,7 +1380,7 @@ static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
 		return -ENOENT;
 }
 
-static const char *proc_pid_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *proc_pid_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct inode *inode = d_inode(dentry);
 	struct path path;
@@ -1394,7 +1394,7 @@ static const char *proc_pid_follow_link(struct dentry *dentry, void **cookie, st
 	if (error)
 		goto out;
 
-	nd_jump_link(nd, &path);
+	nd_jump_link(&path);
 	return NULL;
 out:
 	return ERR_PTR(error);

fs/proc/inode.c

@@ -393,7 +393,7 @@ static const struct file_operations proc_reg_file_ops_no_compat = {
 };
 #endif
 
-static const char *proc_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *proc_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct proc_dir_entry *pde = PDE(d_inode(dentry));
 	if (unlikely(!use_pde(pde)))

fs/proc/namespaces.c

@@ -30,7 +30,7 @@ static const struct proc_ns_operations *ns_entries[] = {
 	&mntns_operations,
 };
 
-static const char *proc_ns_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *proc_ns_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct inode *inode = d_inode(dentry);
 	const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops;
@@ -45,7 +45,7 @@ static const char *proc_ns_follow_link(struct dentry *dentry, void **cookie, str
 	if (ptrace_may_access(task, PTRACE_MODE_READ)) {
 		error = ns_get_path(&ns_path, task, ns_ops);
 		if (!error)
-			nd_jump_link(nd, &ns_path);
+			nd_jump_link(&ns_path);
 	}
 	put_task_struct(task);
 	return error;

fs/proc/self.c

@@ -18,7 +18,7 @@ static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
 	return readlink_copy(buffer, buflen, tmp);
 }
 
-static const char *proc_self_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *proc_self_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct pid_namespace *ns = dentry->d_sb->s_fs_info;
 	pid_t tgid = task_tgid_nr_ns(current, ns);

fs/proc/thread_self.c

@@ -19,7 +19,7 @@ static int proc_thread_self_readlink(struct dentry *dentry, char __user *buffer,
 	return readlink_copy(buffer, buflen, tmp);
 }
 
-static const char *proc_thread_self_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *proc_thread_self_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct pid_namespace *ns = dentry->d_sb->s_fs_info;
 	pid_t tgid = task_tgid_nr_ns(current, ns);

fs/xfs/xfs_iops.c

@@ -416,8 +416,7 @@ xfs_vn_rename(
 STATIC const char *
 xfs_vn_follow_link(
 	struct dentry		*dentry,
-	void			**cookie,
-	struct nameidata	*nd)
+	void			**cookie)
 {
 	char			*link;
 	int			error = -ENOMEM;

include/linux/fs.h

@@ -1608,7 +1608,7 @@ struct file_operations {
 
 struct inode_operations {
 	struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
-	const char * (*follow_link) (struct dentry *, void **, struct nameidata *);
+	const char * (*follow_link) (struct dentry *, void **);
 	int (*permission) (struct inode *, int);
 	struct posix_acl * (*get_acl)(struct inode *, int);
 
@@ -2705,7 +2705,7 @@ extern const struct file_operations generic_ro_fops;
 
 extern int readlink_copy(char __user *, int, const char *);
 extern int page_readlink(struct dentry *, char __user *, int);
-extern const char *page_follow_link_light(struct dentry *, void **, struct nameidata *);
+extern const char *page_follow_link_light(struct dentry *, void **);
 extern void page_put_link(struct dentry *, void *);
 extern int __page_symlink(struct inode *inode, const char *symname, int len,
 		int nofs);
@@ -2722,7 +2722,7 @@ void __inode_sub_bytes(struct inode *inode, loff_t bytes);
 void inode_sub_bytes(struct inode *inode, loff_t bytes);
 loff_t inode_get_bytes(struct inode *inode);
 void inode_set_bytes(struct inode *inode, loff_t bytes);
-const char *simple_follow_link(struct dentry *, void **, struct nameidata *);
+const char *simple_follow_link(struct dentry *, void **);
 extern const struct inode_operations simple_symlink_inode_operations;
 
 extern int iterate_dir(struct file *, struct dir_context *);

include/linux/namei.h

@@ -72,7 +72,7 @@ extern int follow_up(struct path *);
 extern struct dentry *lock_rename(struct dentry *, struct dentry *);
 extern void unlock_rename(struct dentry *, struct dentry *);
 
-extern void nd_jump_link(struct nameidata *nd, struct path *path);
+extern void nd_jump_link(struct path *path);
 
 static inline void nd_terminate_link(void *name, size_t len, size_t maxlen)
 {

mm/shmem.c

@@ -2475,7 +2475,7 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
 	return 0;
 }
 
-static const char *shmem_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *shmem_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct page *page = NULL;
 	int error = shmem_getpage(d_inode(dentry), 0, &page, SGP_READ, NULL);