Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

[pandora-kernel.git] / fs / namei.c

diff --git a/fs/namei.c b/fs/namei.c
index b85f158..145e852 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -501,6 +501,7 @@ struct path {
 static inline int __do_follow_link(struct path *path, struct nameidata *nd)
 {
        int error;
+       void *cookie;
        struct dentry *dentry = path->dentry;
 
        touch_atime(path->mnt, dentry);
@@ -508,13 +509,15 @@ static inline int __do_follow_link(struct path *path, struct nameidata *nd)
 
        if (path->mnt == nd->mnt)
                mntget(path->mnt);
-       error = dentry->d_inode->i_op->follow_link(dentry, nd);
-       if (!error) {
+       cookie = dentry->d_inode->i_op->follow_link(dentry, nd);
+       error = PTR_ERR(cookie);
+       if (!IS_ERR(cookie)) {
                char *s = nd_get_link(nd);
+               error = 0;
                if (s)
                        error = __vfs_follow_link(nd, s);
                if (dentry->d_inode->i_op->put_link)
-                       dentry->d_inode->i_op->put_link(dentry, nd);
+                       dentry->d_inode->i_op->put_link(dentry, nd, cookie);
        }
        dput(dentry);
        mntput(path->mnt);
@@ -522,6 +525,22 @@ static inline int __do_follow_link(struct path *path, struct nameidata *nd)
        return error;
 }
 
+static inline void dput_path(struct path *path, struct nameidata *nd)
+{
+       dput(path->dentry);
+       if (path->mnt != nd->mnt)
+               mntput(path->mnt);
+}
+
+static inline void path_to_nameidata(struct path *path, struct nameidata *nd)
+{
+       dput(nd->dentry);
+       if (nd->mnt != path->mnt)
+               mntput(nd->mnt);
+       nd->mnt = path->mnt;
+       nd->dentry = path->dentry;
+}
+
 /*
  * This limits recursive symlink follows to 8, while
  * limiting consecutive symlinks to 40.
@@ -549,9 +568,7 @@ static inline int do_follow_link(struct path *path, struct nameidata *nd)
        nd->depth--;
        return err;
 loop:
-       dput(path->dentry);
-       if (path->mnt != nd->mnt)
-               mntput(path->mnt);
+       dput_path(path, nd);
        path_release(nd);
        return err;
 }
@@ -810,13 +827,8 @@ static fastcall int __link_path_walk(const char * name, struct nameidata *nd)
                        err = -ENOTDIR; 
                        if (!inode->i_op)
                                break;
-               } else {
-                       dput(nd->dentry);
-                       if (nd->mnt != next.mnt)
-                               mntput(nd->mnt);
-                       nd->mnt = next.mnt;
-                       nd->dentry = next.dentry;
-               }
+               } else
+                       path_to_nameidata(&next, nd);
                err = -ENOTDIR; 
                if (!inode->i_op->lookup)
                        break;
@@ -856,13 +868,8 @@ last_component:
                        if (err)
                                goto return_err;
                        inode = nd->dentry->d_inode;
-               } else {
-                       dput(nd->dentry);
-                       if (nd->mnt != next.mnt)
-                               mntput(nd->mnt);
-                       nd->mnt = next.mnt;
-                       nd->dentry = next.dentry;
-               }
+               } else
+                       path_to_nameidata(&next, nd);
                err = -ENOENT;
                if (!inode)
                        break;
@@ -898,9 +905,7 @@ return_reval:
 return_base:
                return 0;
 out_dput:
-               dput(next.dentry);
-               if (nd->mnt != next.mnt)
-                       mntput(next.mnt);
+               dput_path(&next, nd);
                break;
        }
        path_release(nd);
@@ -1504,11 +1509,7 @@ do_last:
        if (path.dentry->d_inode->i_op && path.dentry->d_inode->i_op->follow_link)
                goto do_link;
 
-       dput(nd->dentry);
-       nd->dentry = path.dentry;
-       if (nd->mnt != path.mnt)
-               mntput(nd->mnt);
-       nd->mnt = path.mnt;
+       path_to_nameidata(&path, nd);
        error = -EISDIR;
        if (path.dentry->d_inode && S_ISDIR(path.dentry->d_inode->i_mode))
                goto exit;
@@ -1519,9 +1520,7 @@ ok:
        return 0;
 
 exit_dput:
-       dput(path.dentry);
-       if (nd->mnt != path.mnt)
-               mntput(path.mnt);
+       dput_path(&path, nd);
 exit:
        path_release(nd);
        return error;
@@ -2344,15 +2343,17 @@ out:
 int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 {
        struct nameidata nd;
-       int res;
+       void *cookie;
+
        nd.depth = 0;
-       res = dentry->d_inode->i_op->follow_link(dentry, &nd);
-       if (!res) {
-               res = vfs_readlink(dentry, buffer, buflen, nd_get_link(&nd));
+       cookie = dentry->d_inode->i_op->follow_link(dentry, &nd);
+       if (!IS_ERR(cookie)) {
+               int res = vfs_readlink(dentry, buffer, buflen, nd_get_link(&nd));
                if (dentry->d_inode->i_op->put_link)
-                       dentry->d_inode->i_op->put_link(dentry, &nd);
+                       dentry->d_inode->i_op->put_link(dentry, &nd, cookie);
+               cookie = ERR_PTR(res);
        }
-       return res;
+       return PTR_ERR(cookie);
 }
 
 int vfs_follow_link(struct nameidata *nd, const char *link)
@@ -2395,23 +2396,20 @@ int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
        return res;
 }
 
-int page_follow_link_light(struct dentry *dentry, struct nameidata *nd)
+void *page_follow_link_light(struct dentry *dentry, struct nameidata *nd)
 {
-       struct page *page;
+       struct page *page = NULL;
        nd_set_link(nd, page_getlink(dentry, &page));
-       return 0;
+       return page;
 }
 
-void page_put_link(struct dentry *dentry, struct nameidata *nd)
+void page_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
 {
-       if (!IS_ERR(nd_get_link(nd))) {
-               struct page *page;
-               page = find_get_page(dentry->d_inode->i_mapping, 0);
-               if (!page)
-                       BUG();
+       struct page *page = cookie;
+
+       if (page) {
                kunmap(page);
                page_cache_release(page);
-               page_cache_release(page);
        }
 }