f2fs: support 64-bits key in f2fs rb-tree node entry

then, we can add specified entry into rb-tree with 64-bits segment time
as key.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/extent_cache.c

@@ -58,6 +58,29 @@ struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
 	return re;
 }
 
+struct rb_node **f2fs_lookup_rb_tree_ext(struct f2fs_sb_info *sbi,
+					struct rb_root_cached *root,
+					struct rb_node **parent,
+					unsigned long long key, bool *leftmost)
+{
+	struct rb_node **p = &root->rb_root.rb_node;
+	struct rb_entry *re;
+
+	while (*p) {
+		*parent = *p;
+		re = rb_entry(*parent, struct rb_entry, rb_node);
+
+		if (key < re->key) {
+			p = &(*p)->rb_left;
+		} else {
+			p = &(*p)->rb_right;
+			*leftmost = false;
+		}
+	}
+
+	return p;
+}
+
 struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
 				struct rb_root_cached *root,
 				struct rb_node **parent,
@@ -166,7 +189,7 @@ struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
 }
 
 bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
-						struct rb_root_cached *root)
+				struct rb_root_cached *root, bool check_key)
 {
 #ifdef CONFIG_F2FS_CHECK_FS
 	struct rb_node *cur = rb_first_cached(root), *next;
@@ -183,13 +206,23 @@ bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
 		cur_re = rb_entry(cur, struct rb_entry, rb_node);
 		next_re = rb_entry(next, struct rb_entry, rb_node);
 
+		if (check_key) {
+			if (cur_re->key > next_re->key) {
+				f2fs_info(sbi, "inconsistent rbtree, "
+					"cur(%llu) next(%llu)",
+					cur_re->key, next_re->key);
+				return false;
+			}
+			goto next;
+		}
+
 		if (cur_re->ofs + cur_re->len > next_re->ofs) {
 			f2fs_info(sbi, "inconsistent rbtree, cur(%u, %u) next(%u, %u)",
 				  cur_re->ofs, cur_re->len,
 				  next_re->ofs, next_re->len);
 			return false;
 		}
-
+next:
 		cur = next;
 	}
 #endif

fs/f2fs/f2fs.h

@@ -612,8 +612,13 @@ enum {
 
 struct rb_entry {
 	struct rb_node rb_node;		/* rb node located in rb-tree */
-	unsigned int ofs;		/* start offset of the entry */
-	unsigned int len;		/* length of the entry */
+	union {
+		struct {
+			unsigned int ofs;	/* start offset of the entry */
+			unsigned int len;	/* length of the entry */
+		};
+		unsigned long long key;		/* 64-bits key */
+	};
 };
 
 struct extent_info {
@@ -3806,6 +3811,10 @@ void f2fs_leave_shrinker(struct f2fs_sb_info *sbi);
  */
 struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
 				struct rb_entry *cached_re, unsigned int ofs);
+struct rb_node **f2fs_lookup_rb_tree_ext(struct f2fs_sb_info *sbi,
+				struct rb_root_cached *root,
+				struct rb_node **parent,
+				unsigned long long key, bool *left_most);
 struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
 				struct rb_root_cached *root,
 				struct rb_node **parent,
@@ -3816,7 +3825,7 @@ struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
 		struct rb_node ***insert_p, struct rb_node **insert_parent,
 		bool force, bool *leftmost);
 bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
-						struct rb_root_cached *root);
+				struct rb_root_cached *root, bool check_key);
 unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink);
 void f2fs_init_extent_tree(struct inode *inode, struct page *ipage);
 void f2fs_drop_extent_tree(struct inode *inode);

fs/f2fs/segment.c

@@ -1525,7 +1525,7 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
 			goto next;
 		if (unlikely(dcc->rbtree_check))
 			f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
-								&dcc->root));
+							&dcc->root, false));
 		blk_start_plug(&plug);
 		list_for_each_entry_safe(dc, tmp, pend_list, list) {
 			f2fs_bug_on(sbi, dc->state != D_PREP);
@@ -2892,7 +2892,7 @@ static unsigned int __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
 	mutex_lock(&dcc->cmd_lock);
 	if (unlikely(dcc->rbtree_check))
 		f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
-								&dcc->root));
+							&dcc->root, false));
 
 	dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
 					NULL, start,