bcachefs: BCH_DATA_OP_drop_extra_replicas

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

diff --git a/fs/bcachefs/bcachefs_ioctl.h b/fs/bcachefs/bcachefs_ioctl.h
index d40ebfe05b0b5809e26c73a5e34747404845e863..18eb325401cf647662ed0b2ec1d1d623669214ae 100644 (file)
--- a/fs/bcachefs/bcachefs_ioctl.h
+++ b/fs/bcachefs/bcachefs_ioctl.h
@@ -177,7 +177,8 @@ struct bch_ioctl_disk_set_state {
        x(scrub,                0)      \
        x(rereplicate,          1)      \
        x(migrate,              2)      \
-       x(rewrite_old_nodes,    3)
+       x(rewrite_old_nodes,    3)      \
+       x(drop_extra_replicas,  4)
 
 enum bch_data_ops {
 #define x(t, n) BCH_DATA_OP_##t = n,

diff --git a/fs/bcachefs/move.c b/fs/bcachefs/move.c
index 0772b973405edb33847198eecccd48106ad7ba40..d99742fbdb19f8218ff6bd5c1a4c6f247684579b 100644 (file)
--- a/fs/bcachefs/move.c
+++ b/fs/bcachefs/move.c
@@ -1013,6 +1013,41 @@ int bch2_scan_old_btree_nodes(struct bch_fs *c, struct bch_move_stats *stats)
        return ret;
 }
 
+static bool drop_extra_replicas_pred(struct bch_fs *c, void *arg,
+                            struct bkey_s_c k,
+                            struct bch_io_opts *io_opts,
+                            struct data_update_opts *data_opts)
+{
+       unsigned durability = bch2_bkey_durability(c, k);
+       unsigned replicas = bkey_is_btree_ptr(k.k)
+               ? c->opts.metadata_replicas
+               : io_opts->data_replicas;
+       const union bch_extent_entry *entry;
+       struct extent_ptr_decoded p;
+       unsigned i = 0;
+
+       bkey_for_each_ptr_decode(k.k, bch2_bkey_ptrs_c(k), p, entry) {
+               unsigned d = bch2_extent_ptr_durability(c, &p);
+
+               if (d && durability - d >= replicas) {
+                       data_opts->kill_ptrs |= BIT(i);
+                       durability -= d;
+               }
+
+               i++;
+       }
+
+       return data_opts->kill_ptrs != 0;
+}
+
+static bool drop_extra_replicas_btree_pred(struct bch_fs *c, void *arg,
+                                  struct btree *b,
+                                  struct bch_io_opts *io_opts,
+                                  struct data_update_opts *data_opts)
+{
+       return drop_extra_replicas_pred(c, arg, bkey_i_to_s_c(&b->key), io_opts, data_opts);
+}
+
 int bch2_data_job(struct bch_fs *c,
                  struct bch_move_stats *stats,
                  struct bch_ioctl_data op)
@@ -1030,11 +1065,8 @@ int bch2_data_job(struct bch_fs *c,
        case BCH_DATA_OP_rereplicate:
                stats->data_type = BCH_DATA_journal;
                ret = bch2_journal_flush_device_pins(&c->journal, -1);
-
                ret = bch2_move_btree(c, start, end,
                                      rereplicate_btree_pred, c, stats) ?: ret;
-               ret = bch2_replicas_gc2(c) ?: ret;
-
                ret = bch2_move_data(c, start, end,
                                     NULL,
                                     stats,
@@ -1049,11 +1081,8 @@ int bch2_data_job(struct bch_fs *c,
 
                stats->data_type = BCH_DATA_journal;
                ret = bch2_journal_flush_device_pins(&c->journal, op.migrate.dev);
-
                ret = bch2_move_btree(c, start, end,
                                      migrate_btree_pred, &op, stats) ?: ret;
-               ret = bch2_replicas_gc2(c) ?: ret;
-
                ret = bch2_move_data(c, start, end,
                                     NULL,
                                     stats,
@@ -1065,6 +1094,15 @@ int bch2_data_job(struct bch_fs *c,
        case BCH_DATA_OP_rewrite_old_nodes:
                ret = bch2_scan_old_btree_nodes(c, stats);
                break;
+       case BCH_DATA_OP_drop_extra_replicas:
+               ret = bch2_move_btree(c, start, end,
+                               drop_extra_replicas_btree_pred, c, stats) ?: ret;
+               ret = bch2_move_data(c, start, end, NULL, stats,
+                               writepoint_hashed((unsigned long) current),
+                               true,
+                               drop_extra_replicas_pred, c) ?: ret;
+               ret = bch2_replicas_gc2(c) ?: ret;
+               break;
        default:
                ret = -EINVAL;
        }