path_init(): store the "base" pointer to file in nameidata itself

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/namei.c b/fs/namei.c
index 398a73b..e967f43 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -496,6 +496,7 @@ struct nameidata {
        unsigned        seq, m_seq;
        int             last_type;
        unsigned        depth;
+       struct file     *base;
        char *saved_names[MAX_NESTED_LINKS + 1];
 };
 
@@ -1845,13 +1846,14 @@ static int link_path_walk(const char *name, struct nameidata *nd)
 }
 
 static int path_init(int dfd, const char *name, unsigned int flags,
-                    struct nameidata *nd, struct file **fp)
+                    struct nameidata *nd)
 {
        int retval = 0;
 
        nd->last_type = LAST_ROOT; /* if there are only slashes... */
        nd->flags = flags | LOOKUP_JUMPED;
        nd->depth = 0;
+       nd->base = NULL;
        if (flags & LOOKUP_ROOT) {
                struct dentry *root = nd->root.dentry;
                struct inode *inode = root->d_inode;
@@ -1921,7 +1923,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
                nd->path = f.file->f_path;
                if (flags & LOOKUP_RCU) {
                        if (f.flags & FDPUT_FPUT)
-                               *fp = f.file;
+                               nd->base = f.file;
                        nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq);
                        rcu_read_lock();
                } else {
@@ -1954,7 +1956,6 @@ static inline int lookup_last(struct nameidata *nd, struct path *path)
 static int path_lookupat(int dfd, const char *name,
                                unsigned int flags, struct nameidata *nd)
 {
-       struct file *base = NULL;
        struct path path;
        int err;
 
@@ -1972,7 +1973,7 @@ static int path_lookupat(int dfd, const char *name,
         * be handled by restarting a traditional ref-walk (which will always
         * be able to complete).
         */
-       err = path_init(dfd, name, flags | LOOKUP_PARENT, nd, &base);
+       err = path_init(dfd, name, flags | LOOKUP_PARENT, nd);
 
        if (unlikely(err))
                goto out;
@@ -2008,8 +2009,8 @@ static int path_lookupat(int dfd, const char *name,
        }
 
 out:
-       if (base)
-               fput(base);
+       if (nd->base)
+               fput(nd->base);
 
        if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) {
                path_put(&nd->root);
@@ -2321,11 +2322,10 @@ out:
 static int
 path_mountpoint(int dfd, const char *name, struct path *path, unsigned int flags)
 {
-       struct file *base = NULL;
        struct nameidata nd;
        int err;
 
-       err = path_init(dfd, name, flags | LOOKUP_PARENT, &nd, &base);
+       err = path_init(dfd, name, flags | LOOKUP_PARENT, &nd);
        if (unlikely(err))
                goto out;
 
@@ -2349,8 +2349,8 @@ path_mountpoint(int dfd, const char *name, struct path *path, unsigned int flags
                put_link(&nd, &link, cookie);
        }
 out:
-       if (base)
-               fput(base);
+       if (nd.base)
+               fput(nd.base);
 
        if (nd.root.mnt && !(nd.flags & LOOKUP_ROOT))
                path_put(&nd.root);
@@ -3205,7 +3205,6 @@ out:
 static struct file *path_openat(int dfd, struct filename *pathname,
                struct nameidata *nd, const struct open_flags *op, int flags)
 {
-       struct file *base = NULL;
        struct file *file;
        struct path path;
        int opened = 0;
@@ -3222,7 +3221,7 @@ static struct file *path_openat(int dfd, struct filename *pathname,
                goto out;
        }
 
-       error = path_init(dfd, pathname->name, flags | LOOKUP_PARENT, nd, &base);
+       error = path_init(dfd, pathname->name, flags | LOOKUP_PARENT, nd);
        if (unlikely(error))
                goto out;
 
@@ -3255,8 +3254,8 @@ static struct file *path_openat(int dfd, struct filename *pathname,
 out:
        if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT))
                path_put(&nd->root);
-       if (base)
-               fput(base);
+       if (nd->base)
+               fput(nd->base);
        if (!(opened & FILE_OPENED)) {
                BUG_ON(!error);
                put_filp(file);