btrfs: replace hardcoded value with SEQ_LAST macro

Define the SEQ_LAST macro to replace (u64)-1 in places where said
value triggers a special-case ref search behavior.

Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Reviewed-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

3 files changed, 12 insertions, 10 deletions

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 6ce7281749a8..24865da63d8f 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -538,7 +538,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
          * slot==nritems. In that case, go to the next leaf before we continue.
          */
         if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
-                if (time_seq == (u64)-1)
+                if (time_seq == SEQ_LAST)
                         ret = btrfs_next_leaf(root, path);
                 else
                         ret = btrfs_next_old_leaf(root, path, time_seq);
@@ -582,7 +582,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
                         eie = NULL;
                 }
 next:
-                if (time_seq == (u64)-1)
+                if (time_seq == SEQ_LAST)
                         ret = btrfs_next_item(root, path);
                 else
                         ret = btrfs_next_old_item(root, path, time_seq);
@@ -634,7 +634,7 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
 
         if (path->search_commit_root)
                 root_level = btrfs_header_level(root->commit_root);
-        else if (time_seq == (u64)-1)
+        else if (time_seq == SEQ_LAST)
                 root_level = btrfs_header_level(root->node);
         else
                 root_level = btrfs_old_root_level(root, time_seq);
@@ -645,7 +645,7 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
         }
 
         path->lowest_level = level;
-        if (time_seq == (u64)-1)
+        if (time_seq == SEQ_LAST)
                 ret = btrfs_search_slot(NULL, root, &ref->key_for_search, path,
                                         0, 0);
         else
@@ -1199,7 +1199,7 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
  *
  * NOTE: This can return values > 0
  *
- * If time_seq is set to (u64)-1, it will not search delayed_refs, and behave
+ * If time_seq is set to SEQ_LAST, it will not search delayed_refs, and behave
  * much like trans == NULL case, the difference only lies in it will not
  * commit root.
  * The special case is for qgroup to search roots in commit_transaction().
@@ -1246,7 +1246,7 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
                 path->skip_locking = 1;
         }
 
-        if (time_seq == (u64)-1)
+        if (time_seq == SEQ_LAST)
                 path->skip_locking = 1;
 
         /*
@@ -1276,9 +1276,9 @@ again:
 
 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
         if (trans && likely(trans->type != __TRANS_DUMMY) &&
-            time_seq != (u64)-1) {
+            time_seq != SEQ_LAST) {
 #else
-        if (trans && time_seq != (u64)-1) {
+        if (trans && time_seq != SEQ_LAST) {
 #endif
                 /*
                  * look if there are updates for this ref queued and lock the
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 7343bf7f2b35..e9d77115e695 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -659,6 +659,8 @@ struct seq_list {
 
 #define SEQ_LIST_INIT(name)     { .list = LIST_HEAD_INIT((name).list), .seq = 0 }
 
+#define SEQ_LAST        ((u64)-1)
+
 enum btrfs_orphan_cleanup_state {
         ORPHAN_CLEANUP_STARTED  = 1,
         ORPHAN_CLEANUP_DONE     = 2,
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index b2fdefc6d191..21647a414aa5 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -2055,12 +2055,12 @@ int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans,
 
                 if (!ret) {
                         /*
-                         * Use (u64)-1 as time_seq to do special search, which
+                         * Use SEQ_LAST as time_seq to do special search, which
                          * doesn't lock tree or delayed_refs and search current
                          * root. It's safe inside commit_transaction().
                          */
                         ret = btrfs_find_all_roots(trans, fs_info,
-                                        record->bytenr, (u64)-1, &new_roots);
+                                        record->bytenr, SEQ_LAST, &new_roots);
                         if (ret < 0)
                                 goto cleanup;
                         if (qgroup_to_skip)