bcachefs: Fix bkey format generation for 32 bit fields

Having a packed format that can represent a field larger than the
unpacked type breaks bkey_packed_successor() assertions - we need to fix this to start using the snapshot filed.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 27 insertions, 1 deletions

diff --git a/fs/bcachefs/move.c b/fs/bcachefs/move.c
index ed18abf8bf14..de3554e3854b 100644
--- a/fs/bcachefs/move.c
+++ b/fs/bcachefs/move.c
@@ -829,13 +829,38 @@ static enum data_cmd migrate_btree_pred(struct bch_fs *c, void *arg,
 	return migrate_pred(c, arg, bkey_i_to_s_c(&b->key), io_opts, data_opts);
 }
 
+static bool bformat_needs_redo(struct bkey_format *f)
+{
+	unsigned i;
+
+	for (i = 0; i < f->nr_fields; i++) {
+		unsigned unpacked_bits = bch2_bkey_format_current.bits_per_field[i];
+		u64 unpacked_mask = ~((~0ULL << 1) << (unpacked_bits - 1));
+		u64 field_offset = le64_to_cpu(f->field_offset[i]);
+
+		if (f->bits_per_field[i] > unpacked_bits)
+			return true;
+
+		if ((f->bits_per_field[i] == unpacked_bits) && field_offset)
+			return true;
+
+		if (((field_offset + ((1ULL << f->bits_per_field[i]) - 1)) &
+		     unpacked_mask) <
+		    field_offset)
+			return true;
+	}
+
+	return false;
+}
+
 static enum data_cmd rewrite_old_nodes_pred(struct bch_fs *c, void *arg,
 					    struct btree *b,
 					    struct bch_io_opts *io_opts,
 					    struct data_opts *data_opts)
 {
 	if (b->version_ondisk != c->sb.version ||
-	    btree_node_need_rewrite(b)) {
+	    btree_node_need_rewrite(b) ||
+	    bformat_needs_redo(&b->format)) {
 		data_opts->target		= 0;
 		data_opts->nr_replicas		= 1;
 		data_opts->btree_insert_flags	= 0;
@@ -856,6 +881,7 @@ int bch2_scan_old_btree_nodes(struct bch_fs *c, struct bch_move_stats *stats)
 	if (!ret) {
 		mutex_lock(&c->sb_lock);
 		c->disk_sb.sb->compat[0] |= 1ULL << BCH_COMPAT_FEAT_EXTENTS_ABOVE_BTREE_UPDATES_DONE;
+		c->disk_sb.sb->compat[0] |= 1ULL << BCH_COMPAT_FEAT_BFORMAT_OVERFLOW_DONE;
 		c->disk_sb.sb->version_min = c->disk_sb.sb->version;
 		bch2_write_super(c);
 		mutex_unlock(&c->sb_lock);