bcachefs: Split out SPOS_MAX

Internal btree code really wants a POS_MAX with all fields ~0; external
code more likely wants the snapshot field to be 0, because when we're
passing it to bch2_trans_get_iter() it's used for the snapshot we're
operating in, which should be 0 for most btrees that don't use
snapshots.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

fs/bcachefs/bcachefs_format.h

@@ -152,7 +152,8 @@ static inline struct bpos SPOS(__u64 inode, __u64 offset, __u32 snapshot)
 }
 
 #define POS_MIN				SPOS(0, 0, 0)
-#define POS_MAX				SPOS(KEY_INODE_MAX, KEY_OFFSET_MAX, KEY_SNAPSHOT_MAX)
+#define POS_MAX				SPOS(KEY_INODE_MAX, KEY_OFFSET_MAX, 0)
+#define SPOS_MAX			SPOS(KEY_INODE_MAX, KEY_OFFSET_MAX, KEY_SNAPSHOT_MAX)
 #define POS(_inode, _offset)		SPOS(_inode, _offset, 0)
 
 /* Empty placeholder struct, for container_of() */

fs/bcachefs/btree_gc.c

@@ -962,7 +962,7 @@ static int bch2_gc_btree_init(struct bch_fs *c,
 		goto fsck_err;
 	}
 
-	if (mustfix_fsck_err_on(bpos_cmp(b->data->max_key, POS_MAX), c,
+	if (mustfix_fsck_err_on(bpos_cmp(b->data->max_key, SPOS_MAX), c,
 			"btree root with incorrect max_key: %s",
 			(bch2_bpos_to_text(&PBUF(buf), b->data->max_key), buf))) {
 		bch_err(c, "repair unimplemented");

fs/bcachefs/btree_gc.h

@@ -87,7 +87,7 @@ static inline struct gc_pos gc_pos_btree_node(struct btree *b)
  */
 static inline struct gc_pos gc_pos_btree_root(enum btree_id id)
 {
-	return gc_pos_btree(id, POS_MAX, BTREE_MAX_DEPTH);
+	return gc_pos_btree(id, SPOS_MAX, BTREE_MAX_DEPTH);
 }
 
 static inline bool gc_visited(struct bch_fs *c, struct gc_pos pos)

fs/bcachefs/btree_iter.c

@@ -1081,7 +1081,7 @@ static inline int btree_iter_lock_root(struct btree_iter *iter,
 		}
 
 		lock_type = __btree_lock_want(iter, iter->level);
-		if (unlikely(!btree_node_lock(b, POS_MAX, iter->level,
+		if (unlikely(!btree_node_lock(b, SPOS_MAX, iter->level,
 					      iter, lock_type,
 					      lock_root_check_fn, rootp,
 					      trace_ip)))
@@ -1602,7 +1602,7 @@ static void btree_iter_set_search_pos(struct btree_iter *iter, struct bpos new_p
 inline bool bch2_btree_iter_advance(struct btree_iter *iter)
 {
 	struct bpos pos = iter->k.p;
-	bool ret = bpos_cmp(pos, POS_MAX) != 0;
+	bool ret = bpos_cmp(pos, SPOS_MAX) != 0;
 
 	if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
 		pos = bkey_successor(iter, pos);
@@ -1624,7 +1624,7 @@ inline bool bch2_btree_iter_rewind(struct btree_iter *iter)
 static inline bool btree_iter_set_pos_to_next_leaf(struct btree_iter *iter)
 {
 	struct bpos next_pos = iter->l[0].b->key.k.p;
-	bool ret = bpos_cmp(next_pos, POS_MAX) != 0;
+	bool ret = bpos_cmp(next_pos, SPOS_MAX) != 0;
 
 	/*
 	 * Typically, we don't want to modify iter->pos here, since that
@@ -1634,7 +1634,7 @@ static inline bool btree_iter_set_pos_to_next_leaf(struct btree_iter *iter)
 	if (ret)
 		btree_iter_set_search_pos(iter, bpos_successor(next_pos));
 	else
-		bch2_btree_iter_set_pos(iter, POS_MAX);
+		bch2_btree_iter_set_pos(iter, SPOS_MAX);
 
 	return ret;
 }

fs/bcachefs/btree_update_interior.c

@@ -367,7 +367,7 @@ static struct btree *__btree_root_alloc(struct btree_update *as, unsigned level)
 	struct btree *b = bch2_btree_node_alloc(as, level);
 
 	btree_set_min(b, POS_MIN);
-	btree_set_max(b, POS_MAX);
+	btree_set_max(b, SPOS_MAX);
 	b->data->format = bch2_btree_calc_format(b);
 
 	btree_node_set_format(b, b->data->format);
@@ -1590,7 +1590,7 @@ int __bch2_foreground_maybe_merge(struct bch_fs *c,
 	b = iter->l[level].b;
 
 	if ((sib == btree_prev_sib && !bpos_cmp(b->data->min_key, POS_MIN)) ||
-	    (sib == btree_next_sib && !bpos_cmp(b->data->max_key, POS_MAX))) {
+	    (sib == btree_next_sib && !bpos_cmp(b->data->max_key, SPOS_MAX))) {
 		b->sib_u64s[sib] = U16_MAX;
 		goto out;
 	}
@@ -2014,7 +2014,7 @@ void bch2_btree_root_alloc(struct bch_fs *c, enum btree_id id)
 	b->c.btree_id	= id;
 
 	bkey_btree_ptr_init(&b->key);
-	b->key.k.p = POS_MAX;
+	b->key.k.p = SPOS_MAX;
 	*((u64 *) bkey_i_to_btree_ptr(&b->key)->v.start) = U64_MAX - id;
 
 	bch2_bset_init_first(b, &b->data->keys);
@@ -2022,7 +2022,7 @@ void bch2_btree_root_alloc(struct bch_fs *c, enum btree_id id)
 
 	b->data->flags = 0;
 	btree_set_min(b, POS_MIN);
-	btree_set_max(b, POS_MAX);
+	btree_set_max(b, SPOS_MAX);
 	b->data->format = bch2_btree_calc_format(b);
 	btree_node_set_format(b, b->data->format);
 

fs/bcachefs/debug.c

@@ -313,7 +313,7 @@ static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
 	if (err)
 		return err;
 
-	if (!i->size || !bpos_cmp(POS_MAX, i->from))
+	if (!i->size || !bpos_cmp(SPOS_MAX, i->from))
 		return i->ret;
 
 	bch2_trans_init(&trans, i->c, 0, 0);
@@ -329,7 +329,7 @@ static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
 		 * can't easily correctly restart a btree node traversal across
 		 * all nodes, meh
 		 */
-		i->from = bpos_cmp(POS_MAX, b->key.k.p)
+		i->from = bpos_cmp(SPOS_MAX, b->key.k.p)
 			? bpos_successor(b->key.k.p)
 			: b->key.k.p;
 

fs/bcachefs/move.c

@@ -769,7 +769,7 @@ static int bch2_move_btree(struct bch_fs *c,
 				break;
 
 			if ((cmp_int(id, end_btree_id) ?:
-			     bkey_cmp(b->key.k.p, end_pos)) > 0)
+			     bpos_cmp(b->key.k.p, end_pos)) > 0)
 				break;
 
 			stats->pos = iter->pos;
@@ -921,7 +921,7 @@ int bch2_scan_old_btree_nodes(struct bch_fs *c, struct bch_move_stats *stats)
 
 	ret = bch2_move_btree(c,
 			      0,		POS_MIN,
-			      BTREE_ID_NR,	POS_MAX,
+			      BTREE_ID_NR,	SPOS_MAX,
 			      rewrite_old_nodes_pred, c, stats);
 	if (!ret) {
 		mutex_lock(&c->sb_lock);