[PATCH] VFS: Permit filesystem to override root dentry on mount

[mirror_ubuntu-zesty-kernel.git] / fs / debugfs / inode.c

diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index a86ac4aeaedb8136a14861e1aa16be95fbd05549..440128ebef3b04ed4a90c0d247475f1a701b4c2c 100644 (file)
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -67,12 +67,13 @@ static struct inode *debugfs_get_inode(struct super_block *sb, int mode, dev_t d
 static int debugfs_mknod(struct inode *dir, struct dentry *dentry,
                         int mode, dev_t dev)
 {
-       struct inode *inode = debugfs_get_inode(dir->i_sb, mode, dev);
+       struct inode *inode;
        int error = -EPERM;
 
        if (dentry->d_inode)
                return -EEXIST;
 
+       inode = debugfs_get_inode(dir->i_sb, mode, dev);
        if (inode) {
                d_instantiate(dentry, inode);
                dget(dentry);
@@ -110,11 +111,11 @@ static int debug_fill_super(struct super_block *sb, void *data, int silent)
        return simple_fill_super(sb, DEBUGFS_MAGIC, debug_files);
 }
 
-static struct super_block *debug_get_sb(struct file_system_type *fs_type,
-                                       int flags, const char *dev_name,
-                                       void *data)
+static int debug_get_sb(struct file_system_type *fs_type,
+                       int flags, const char *dev_name,
+                       void *data, struct vfsmount *mnt)
 {
-       return get_sb_single(fs_type, flags, data, debug_fill_super);
+       return get_sb_single(fs_type, flags, data, debug_fill_super, mnt);
 }
 
 static struct file_system_type debug_fs_type = {
@@ -146,7 +147,7 @@ static int debugfs_create_by_name(const char *name, mode_t mode,
        }
 
        *dentry = NULL;
-       down(&parent->d_inode->i_sem);
+       mutex_lock(&parent->d_inode->i_mutex);
        *dentry = lookup_one_len(name, parent, strlen(name));
        if (!IS_ERR(dentry)) {
                if ((mode & S_IFMT) == S_IFDIR)
@@ -155,7 +156,7 @@ static int debugfs_create_by_name(const char *name, mode_t mode,
                        error = debugfs_create(parent->d_inode, *dentry, mode);
        } else
                error = PTR_ERR(dentry);
-       up(&parent->d_inode->i_sem);
+       mutex_unlock(&parent->d_inode->i_mutex);
 
        return error;
 }
@@ -191,7 +192,7 @@ static int debugfs_create_by_name(const char *name, mode_t mode,
  */
 struct dentry *debugfs_create_file(const char *name, mode_t mode,
                                   struct dentry *parent, void *data,
-                                  struct file_operations *fops)
+                                  const struct file_operations *fops)
 {
        struct dentry *dentry = NULL;
        int error;
@@ -273,7 +274,7 @@ void debugfs_remove(struct dentry *dentry)
        if (!parent || !parent->d_inode)
                return;
 
-       down(&parent->d_inode->i_sem);
+       mutex_lock(&parent->d_inode->i_mutex);
        if (debugfs_positive(dentry)) {
                if (dentry->d_inode) {
                        if (S_ISDIR(dentry->d_inode->i_mode))
@@ -283,7 +284,7 @@ void debugfs_remove(struct dentry *dentry)
                dput(dentry);
                }
        }
-       up(&parent->d_inode->i_sem);
+       mutex_unlock(&parent->d_inode->i_mutex);
        simple_release_fs(&debugfs_mount, &debugfs_mount_count);
 }
 EXPORT_SYMBOL_GPL(debugfs_remove);