ext4: don't allow overlapping system zones

[linux-2.6-microblaze.git] / fs / ext4 / block_validity.c

diff --git a/fs/ext4/block_validity.c b/fs/ext4/block_validity.c
index 16e9b2f..b394a50 100644 (file)
--- a/fs/ext4/block_validity.c
+++ b/fs/ext4/block_validity.c
@@ -68,7 +68,7 @@ static int add_system_zone(struct ext4_system_blocks *system_blks,
                           ext4_fsblk_t start_blk,
                           unsigned int count)
 {
-       struct ext4_system_zone *new_entry = NULL, *entry;
+       struct ext4_system_zone *new_entry, *entry;
        struct rb_node **n = &system_blks->root.rb_node, *node;
        struct rb_node *parent = NULL, *new_node = NULL;
 
@@ -79,30 +79,20 @@ static int add_system_zone(struct ext4_system_blocks *system_blks,
                        n = &(*n)->rb_left;
                else if (start_blk >= (entry->start_blk + entry->count))
                        n = &(*n)->rb_right;
-               else {
-                       if (start_blk + count > (entry->start_blk +
-                                                entry->count))
-                               entry->count = (start_blk + count -
-                                               entry->start_blk);
-                       new_node = *n;
-                       new_entry = rb_entry(new_node, struct ext4_system_zone,
-                                            node);
-                       break;
-               }
+               else    /* Unexpected overlap of system zones. */
+                       return -EFSCORRUPTED;
        }
 
-       if (!new_entry) {
-               new_entry = kmem_cache_alloc(ext4_system_zone_cachep,
-                                            GFP_KERNEL);
-               if (!new_entry)
-                       return -ENOMEM;
-               new_entry->start_blk = start_blk;
-               new_entry->count = count;
-               new_node = &new_entry->node;
-
-               rb_link_node(new_node, parent, n);
-               rb_insert_color(new_node, &system_blks->root);
-       }
+       new_entry = kmem_cache_alloc(ext4_system_zone_cachep,
+                                    GFP_KERNEL);
+       if (!new_entry)
+               return -ENOMEM;
+       new_entry->start_blk = start_blk;
+       new_entry->count = count;
+       new_node = &new_entry->node;
+
+       rb_link_node(new_node, parent, n);
+       rb_insert_color(new_node, &system_blks->root);
 
        /* Can we merge to the left? */
        node = rb_prev(new_node);