[JFFS2] Fix summary handling of unknown but compatible nodes.

For RWCOMPAT and ROCOMPAT nodes, we should still allow the mount to
succeed. Just abandon the summary and fall through to the full scan.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 20 insertions, 4 deletions

diff --git a/fs/jffs2/summary.c b/fs/jffs2/summary.c
index 53a84b468cf..9ced3aa9581 100644
--- a/fs/jffs2/summary.c
+++ b/fs/jffs2/summary.c
@@ -554,9 +554,21 @@ static int jffs2_sum_process_sum_data(struct jffs2_sb_info *c, struct jffs2_eras
 			}
 #endif
 			default : {
-printk("nodetype = %#04x\n",je16_to_cpu(((struct jffs2_sum_unknown_flash *)sp)->nodetype));
-				JFFS2_WARNING("Unsupported node type found in summary! Exiting...");
-				return -EIO;
+				uint16_t nodetype = je16_to_cpu(((struct jffs2_sum_unknown_flash *)sp)->nodetype);
+				JFFS2_WARNING("Unsupported node type %x found in summary! Exiting...\n", nodetype);
+				if ((nodetype & JFFS2_COMPAT_MASK) == JFFS2_FEATURE_INCOMPAT)
+					return -EIO;
+
+				/* For compatible node types, just fall back to the full scan */
+				c->wasted_size -= jeb->wasted_size;
+				c->free_size += c->sector_size - jeb->free_size;
+				c->used_size -= jeb->used_size;
+				c->dirty_size -= jeb->dirty_size;
+				jeb->wasted_size = jeb->used_size = jeb->dirty_size = 0;
+				jeb->free_size = c->sector_size;
+
+				jffs2_free_all_node_refs(c, jeb);
+				return -ENOTRECOVERABLE;
 			}
 		}
 	}
@@ -642,8 +654,12 @@ int jffs2_sum_scan_sumnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb
 	}
 
 	ret = jffs2_sum_process_sum_data(c, jeb, summary, pseudo_random);
+	/* -ENOTRECOVERABLE isn't a fatal error -- it means we should do a full
+	   scan of this eraseblock. So return zero */
+	if (ret == -ENOTRECOVERABLE)
+		return 0;
 	if (ret)
-		return ret;
+		return ret;		/* real error */
 
 	/* for PARANOIA_CHECK */
 	cache_ref = jffs2_alloc_raw_node_ref();