UBIFS: add debugfs knob to switch to R/O mode
This patch adds another debugfs knob which switches UBIFS to R/O mode.
I needed it while trying to reproduce the 'first log node is not CS node'
bug. Without this debugfs knob you have to perform a power cut to repruduce
the bug. The knob is named 'ro_error' and all it does is it sets the
'ro_error' UBIFS flag which makes UBIFS disallow any further writes - even
write-back will fail with -EROFS. Useful for debugging.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index 486a8e0..8b8cc4e 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -79,6 +79,10 @@
* @dfs_chk_lprops: debugfs knob to enable UBIFS LEP properties extra checks
* @dfs_chk_fs: debugfs knob to enable UBIFS contents extra checks
* @dfs_tst_rcvry: debugfs knob to enable UBIFS recovery testing
+ * @dfs_ro_error: debugfs knob to switch UBIFS to R/O mode (different to
+ * re-mounting to R/O mode because it does not flush any buffers
+ * and UBIFS just starts returning -EROFS on all write
+ * operations)
*/
struct ubifs_debug_info {
struct ubifs_zbranch old_zroot;
@@ -122,6 +126,7 @@
struct dentry *dfs_chk_lprops;
struct dentry *dfs_chk_fs;
struct dentry *dfs_tst_rcvry;
+ struct dentry *dfs_ro_error;
};
/**