mmc: block: Add missing mmc_blk_put() in power_ro_lock_show()

[linux-2.6-block.git] / fs / seq_file.c

diff --git a/fs/seq_file.c b/fs/seq_file.c
index 52b492721603db1e37a8fb424a7f112a4932da2f..ce9e39fd5dafc768c27b2ceaa4e69a02c3ed1e6e 100644 (file)
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -48,18 +48,21 @@ static void *seq_buf_alloc(unsigned long size)
  *     ERR_PTR(error).  In the end of sequence they return %NULL. ->show()
  *     returns 0 in case of success and negative number in case of error.
  *     Returning SEQ_SKIP means "discard this element and move on".
+ *     Note: seq_open() will allocate a struct seq_file and store its
+ *     pointer in @file->private_data. This pointer should not be modified.
  */
 int seq_open(struct file *file, const struct seq_operations *op)
 {
-       struct seq_file *p = file->private_data;
+       struct seq_file *p;
+
+       WARN_ON(file->private_data);
+
+       p = kzalloc(sizeof(*p), GFP_KERNEL);
+       if (!p)
+               return -ENOMEM;
+
+       file->private_data = p;
 
-       if (!p) {
-               p = kmalloc(sizeof(*p), GFP_KERNEL);
-               if (!p)
-                       return -ENOMEM;
-               file->private_data = p;
-       }
-       memset(p, 0, sizeof(*p));
        mutex_init(&p->lock);
        p->op = op;
 #ifdef CONFIG_USER_NS
@@ -487,6 +490,20 @@ int seq_path(struct seq_file *m, const struct path *path, const char *esc)
 }
 EXPORT_SYMBOL(seq_path);
 
+/**
+ * seq_file_path - seq_file interface to print a pathname of a file
+ * @m: the seq_file handle
+ * @file: the struct file to print
+ * @esc: set of characters to escape in the output
+ *
+ * return the absolute path to the file.
+ */
+int seq_file_path(struct seq_file *m, struct file *file, const char *esc)
+{
+       return seq_path(m, &file->f_path, esc);
+}
+EXPORT_SYMBOL(seq_file_path);
+
 /*
  * Same as seq_path, but relative to supplied root.
  */