Merge tag 'iwlwifi-next-for-kalle-2014-12-30' of https://git.kernel.org/pub/scm/linux...

[cascardo/linux.git] / fs / namei.c

diff --git a/fs/namei.c b/fs/namei.c
index ca81416..bc35b02 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -487,6 +487,19 @@ void path_put(const struct path *path)
 }
 EXPORT_SYMBOL(path_put);
 
+struct nameidata {
+       struct path     path;
+       struct qstr     last;
+       struct path     root;
+       struct inode    *inode; /* path.dentry.d_inode */
+       unsigned int    flags;
+       unsigned        seq, m_seq;
+       int             last_type;
+       unsigned        depth;
+       struct file     *base;
+       char *saved_names[MAX_NESTED_LINKS + 1];
+};
+
 /*
  * Path walking has 2 modes, rcu-walk and ref-walk (see
  * Documentation/filesystems/path-lookup.txt).  In situations when we can't
@@ -695,6 +708,18 @@ void nd_jump_link(struct nameidata *nd, struct path *path)
        nd->flags |= LOOKUP_JUMPED;
 }
 
+void nd_set_link(struct nameidata *nd, char *path)
+{
+       nd->saved_names[nd->depth] = path;
+}
+EXPORT_SYMBOL(nd_set_link);
+
+char *nd_get_link(struct nameidata *nd)
+{
+       return nd->saved_names[nd->depth];
+}
+EXPORT_SYMBOL(nd_get_link);
+
 static inline void put_link(struct nameidata *nd, struct path *link, void *cookie)
 {
        struct inode *inode = link->dentry->d_inode;
@@ -1821,13 +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->flags = flags | LOOKUP_JUMPED | LOOKUP_PARENT;
        nd->depth = 0;
+       nd->base = NULL;
        if (flags & LOOKUP_ROOT) {
                struct dentry *root = nd->root.dentry;
                struct inode *inode = root->d_inode;
@@ -1847,7 +1873,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
                } else {
                        path_get(&nd->path);
                }
-               return 0;
+               goto done;
        }
 
        nd->root.mnt = NULL;
@@ -1897,7 +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 {
@@ -1908,13 +1934,26 @@ static int path_init(int dfd, const char *name, unsigned int flags,
 
        nd->inode = nd->path.dentry->d_inode;
        if (!(flags & LOOKUP_RCU))
-               return 0;
+               goto done;
        if (likely(!read_seqcount_retry(&nd->path.dentry->d_seq, nd->seq)))
-               return 0;
+               goto done;
        if (!(nd->flags & LOOKUP_ROOT))
                nd->root.mnt = NULL;
        rcu_read_unlock();
        return -ECHILD;
+done:
+       current->total_link_count = 0;
+       return link_path_walk(name, nd);
+}
+
+static void path_cleanup(struct nameidata *nd)
+{
+       if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) {
+               path_put(&nd->root);
+               nd->root.mnt = NULL;
+       }
+       if (unlikely(nd->base))
+               fput(nd->base);
 }
 
 static inline int lookup_last(struct nameidata *nd, struct path *path)
@@ -1930,7 +1969,6 @@ 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;
 
@@ -1948,14 +1986,7 @@ 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);
-
-       if (unlikely(err))
-               goto out;
-
-       current->total_link_count = 0;
-       err = link_path_walk(name, nd);
-
+       err = path_init(dfd, name, flags, nd);
        if (!err && !(flags & LOOKUP_PARENT)) {
                err = lookup_last(nd, &path);
                while (err > 0) {
@@ -1983,14 +2014,7 @@ static int path_lookupat(int dfd, const char *name,
                }
        }
 
-out:
-       if (base)
-               fput(base);
-
-       if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) {
-               path_put(&nd->root);
-               nd->root.mnt = NULL;
-       }
+       path_cleanup(nd);
        return err;
 }
 
@@ -2297,19 +2321,13 @@ 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, &nd);
        if (unlikely(err))
                goto out;
 
-       current->total_link_count = 0;
-       err = link_path_walk(name, &nd);
-       if (err)
-               goto out;
-
        err = mountpoint_last(&nd, path);
        while (err > 0) {
                void *cookie;
@@ -2325,12 +2343,7 @@ 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.root.mnt && !(nd.flags & LOOKUP_ROOT))
-               path_put(&nd.root);
-
+       path_cleanup(&nd);
        return err;
 }
 
@@ -3181,7 +3194,6 @@ 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;
@@ -3198,12 +3210,7 @@ static struct file *path_openat(int dfd, struct filename *pathname,
                goto out;
        }
 
-       error = path_init(dfd, pathname->name, flags | LOOKUP_PARENT, nd, &base);
-       if (unlikely(error))
-               goto out;
-
-       current->total_link_count = 0;
-       error = link_path_walk(pathname->name, nd);
+       error = path_init(dfd, pathname->name, flags, nd);
        if (unlikely(error))
                goto out;
 
@@ -3229,10 +3236,7 @@ static struct file *path_openat(int dfd, struct filename *pathname,
                put_link(nd, &link, cookie);
        }
 out:
-       if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT))
-               path_put(&nd->root);
-       if (base)
-               fput(base);
+       path_cleanup(nd);
        if (!(opened & FILE_OPENED)) {
                BUG_ON(!error);
                put_filp(file);