From: Al Viro <v...@zeniv.linux.org.uk>

don't bother with separate variables for link and cookie in trailing
symlink loops; use nd->stack[0] for that.  That makes *all* callers
of put_link() (and follow_link()) operate on nd->stack[nd->depth].link
and nd->stack[nd->depth].cookie.  Trim the argument lists.

Signed-off-by: Al Viro <v...@zeniv.linux.org.uk>
---
 fs/namei.c | 42 ++++++++++++++++++++----------------------
 1 file changed, 20 insertions(+), 22 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 1c967d1..a8d6751 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -752,12 +752,14 @@ static inline char *nd_get_link(struct nameidata *nd)
        return nd->stack[nd->depth].body;
 }
 
-static inline void put_link(struct nameidata *nd, struct path *link, void 
*cookie)
+static inline void put_link(struct nameidata *nd)
 {
-       struct inode *inode = link->dentry->d_inode;
+       struct saved *last = nd->stack + nd->depth;
+       struct inode *inode = last->link.dentry->d_inode;
        if (inode->i_op->put_link)
-               inode->i_op->put_link(link->dentry, nd_get_link(nd), cookie);
-       path_put(link);
+               inode->i_op->put_link(last->link.dentry, last->body,
+                                     last->cookie);
+       path_put(&last->link);
 }
 
 int sysctl_protected_symlinks __read_mostly = 0;
@@ -925,14 +927,16 @@ out:
        return res;
 }
 
-static int follow_link(struct path *link, struct nameidata *nd, void **p)
+static int follow_link(struct nameidata *nd, struct path *link)
 {
        char *s;
        int error = may_follow_link(link, nd);
+       struct saved *last = nd->stack + nd->depth;
        if (unlikely(error))
                return error;
        nd->flags |= LOOKUP_PARENT;
-       s = get_link(link, nd, p);
+       last->link = *link;
+       s = get_link(&last->link, nd, &last->cookie);
        if (unlikely(IS_ERR(s)))
                return PTR_ERR(s);
        if (unlikely(!s))
@@ -948,7 +952,7 @@ static int follow_link(struct path *link, struct nameidata 
*nd, void **p)
        nd->inode = nd->path.dentry->d_inode;
        error = link_path_walk(s, nd);
        if (unlikely(error))
-               put_link(nd, link, *p);
+               put_link(nd);
        return error;
 }
 
@@ -1869,7 +1873,7 @@ Walked:
                        err = 0;
                        if (unlikely(!s)) {
                                /* jumped */
-                               put_link(nd, &last->link, last->cookie);
+                               put_link(nd);
                                nd->link_count--;
                                nd->depth--;
                                last--;
@@ -1900,7 +1904,7 @@ Walked:
        terminate_walk(nd);
 Err:
        while (unlikely(nd->depth)) {
-               put_link(nd, &last->link, last->cookie);
+               put_link(nd);
                nd->link_count--;
                nd->depth--;
                last--;
@@ -1910,7 +1914,7 @@ OK:
        if (unlikely(nd->depth)) {
                name = last->name;
                err = walk_component(nd, &next, LOOKUP_FOLLOW);
-               put_link(nd, &last->link, last->cookie);
+               put_link(nd);
                nd->link_count--;
                nd->depth--;
                last--;
@@ -2065,13 +2069,11 @@ static int path_lookupat(int dfd, const struct filename 
*name,
        if (!err && !(flags & LOOKUP_PARENT)) {
                err = lookup_last(nd, &path);
                while (err > 0) {
-                       void *cookie;
-                       struct path link = path;
-                       err = follow_link(&link, nd, &cookie);
+                       err = follow_link(nd, &path);
                        if (err)
                                break;
                        err = lookup_last(nd, &path);
-                       put_link(nd, &link, cookie);
+                       put_link(nd);
                }
        }
 
@@ -2426,13 +2428,11 @@ path_mountpoint(int dfd, const struct filename *name, 
struct path *path,
 
        err = mountpoint_last(&nd, path);
        while (err > 0) {
-               void *cookie;
-               struct path link = *path;
-               err = follow_link(&link, &nd, &cookie);
+               err = follow_link(&nd, path);
                if (err)
                        break;
                err = mountpoint_last(&nd, path);
-               put_link(&nd, &link, cookie);
+               put_link(&nd);
        }
 out:
        path_cleanup(&nd);
@@ -3310,8 +3310,6 @@ static struct file *path_openat(int dfd, struct filename 
*pathname,
 
        error = do_last(nd, &path, file, op, &opened, pathname);
        while (unlikely(error > 0)) { /* trailing symlink */
-               struct path link = path;
-               void *cookie;
                if (!(nd->flags & LOOKUP_FOLLOW)) {
                        path_put_conditional(&path, nd);
                        path_put(&nd->path);
@@ -3319,11 +3317,11 @@ static struct file *path_openat(int dfd, struct 
filename *pathname,
                        break;
                }
                nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL);
-               error = follow_link(&link, nd, &cookie);
+               error = follow_link(nd, &path);
                if (unlikely(error))
                        break;
                error = do_last(nd, &path, file, op, &opened, pathname);
-               put_link(nd, &link, cookie);
+               put_link(nd);
        }
 out:
        path_cleanup(nd);
-- 
2.1.4

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