debugfs: add support for self-protecting attribute file fops

[linux-2.6-microblaze.git] / fs / debugfs / file.c

diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index 6eb58a8..8ef56d9 100644 (file)
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -284,6 +284,34 @@ const struct file_operations debugfs_full_proxy_file_operations = {
        .open = full_proxy_open,
 };
 
+ssize_t debugfs_attr_read(struct file *file, char __user *buf,
+                       size_t len, loff_t *ppos)
+{
+       ssize_t ret;
+       int srcu_idx;
+
+       ret = debugfs_use_file_start(F_DENTRY(file), &srcu_idx);
+       if (likely(!ret))
+               ret = simple_attr_read(file, buf, len, ppos);
+       debugfs_use_file_finish(srcu_idx);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(debugfs_attr_read);
+
+ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
+                        size_t len, loff_t *ppos)
+{
+       ssize_t ret;
+       int srcu_idx;
+
+       ret = debugfs_use_file_start(F_DENTRY(file), &srcu_idx);
+       if (likely(!ret))
+               ret = simple_attr_write(file, buf, len, ppos);
+       debugfs_use_file_finish(srcu_idx);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(debugfs_attr_write);
+
 static struct dentry *debugfs_create_mode(const char *name, umode_t mode,
                                          struct dentry *parent, void *value,
                                          const struct file_operations *fops,