move Rust sources to top level, C sources into c_src

[bcachefs-tools-debian] / c_src / libbcachefs / migrate.c

diff --git a/c_src/libbcachefs/migrate.c b/c_src/libbcachefs/migrate.c
new file mode 100644 (file)
index 0000000..5623cee
--- /dev/null
+++ b/c_src/libbcachefs/migrate.c
@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Code for moving data off a device.
+ */
+
+#include "bcachefs.h"
+#include "bkey_buf.h"
+#include "btree_update.h"
+#include "btree_update_interior.h"
+#include "buckets.h"
+#include "errcode.h"
+#include "extents.h"
+#include "io_write.h"
+#include "journal.h"
+#include "keylist.h"
+#include "migrate.h"
+#include "move.h"
+#include "replicas.h"
+#include "super-io.h"
+
+static int drop_dev_ptrs(struct bch_fs *c, struct bkey_s k,
+                        unsigned dev_idx, int flags, bool metadata)
+{
+       unsigned replicas = metadata ? c->opts.metadata_replicas : c->opts.data_replicas;
+       unsigned lost = metadata ? BCH_FORCE_IF_METADATA_LOST : BCH_FORCE_IF_DATA_LOST;
+       unsigned degraded = metadata ? BCH_FORCE_IF_METADATA_DEGRADED : BCH_FORCE_IF_DATA_DEGRADED;
+       unsigned nr_good;
+
+       bch2_bkey_drop_device(k, dev_idx);
+
+       nr_good = bch2_bkey_durability(c, k.s_c);
+       if ((!nr_good && !(flags & lost)) ||
+           (nr_good < replicas && !(flags & degraded)))
+               return -EINVAL;
+
+       return 0;
+}
+
+static int bch2_dev_usrdata_drop_key(struct btree_trans *trans,
+                                    struct btree_iter *iter,
+                                    struct bkey_s_c k,
+                                    unsigned dev_idx,
+                                    int flags)
+{
+       struct bch_fs *c = trans->c;
+       struct bkey_i *n;
+       int ret;
+
+       if (!bch2_bkey_has_device_c(k, dev_idx))
+               return 0;
+
+       n = bch2_bkey_make_mut(trans, iter, &k, BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE);
+       ret = PTR_ERR_OR_ZERO(n);
+       if (ret)
+               return ret;
+
+       ret = drop_dev_ptrs(c, bkey_i_to_s(n), dev_idx, flags, false);
+       if (ret)
+               return ret;
+
+       /*
+        * If the new extent no longer has any pointers, bch2_extent_normalize()
+        * will do the appropriate thing with it (turning it into a
+        * KEY_TYPE_error key, or just a discard if it was a cached extent)
+        */
+       bch2_extent_normalize(c, bkey_i_to_s(n));
+
+       /*
+        * Since we're not inserting through an extent iterator
+        * (BTREE_ITER_ALL_SNAPSHOTS iterators aren't extent iterators),
+        * we aren't using the extent overwrite path to delete, we're
+        * just using the normal key deletion path:
+        */
+       if (bkey_deleted(&n->k))
+               n->k.size = 0;
+       return 0;
+}
+
+static int bch2_dev_usrdata_drop(struct bch_fs *c, unsigned dev_idx, int flags)
+{
+       struct btree_trans *trans = bch2_trans_get(c);
+       enum btree_id id;
+       int ret = 0;
+
+       for (id = 0; id < BTREE_ID_NR; id++) {
+               if (!btree_type_has_ptrs(id))
+                       continue;
+
+               ret = for_each_btree_key_commit(trans, iter, id, POS_MIN,
+                               BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS, k,
+                               NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
+                       bch2_dev_usrdata_drop_key(trans, &iter, k, dev_idx, flags));
+               if (ret)
+                       break;
+       }
+
+       bch2_trans_put(trans);
+
+       return ret;
+}
+
+static int bch2_dev_metadata_drop(struct bch_fs *c, unsigned dev_idx, int flags)
+{
+       struct btree_trans *trans;
+       struct btree_iter iter;
+       struct closure cl;
+       struct btree *b;
+       struct bkey_buf k;
+       unsigned id;
+       int ret;
+
+       /* don't handle this yet: */
+       if (flags & BCH_FORCE_IF_METADATA_LOST)
+               return -EINVAL;
+
+       trans = bch2_trans_get(c);
+       bch2_bkey_buf_init(&k);
+       closure_init_stack(&cl);
+
+       for (id = 0; id < BTREE_ID_NR; id++) {
+               bch2_trans_node_iter_init(trans, &iter, id, POS_MIN, 0, 0,
+                                         BTREE_ITER_PREFETCH);
+retry:
+               ret = 0;
+               while (bch2_trans_begin(trans),
+                      (b = bch2_btree_iter_peek_node(&iter)) &&
+                      !(ret = PTR_ERR_OR_ZERO(b))) {
+                       if (!bch2_bkey_has_device_c(bkey_i_to_s_c(&b->key), dev_idx))
+                               goto next;
+
+                       bch2_bkey_buf_copy(&k, c, &b->key);
+
+                       ret = drop_dev_ptrs(c, bkey_i_to_s(k.k),
+                                           dev_idx, flags, true);
+                       if (ret) {
+                               bch_err(c, "Cannot drop device without losing data");
+                               break;
+                       }
+
+                       ret = bch2_btree_node_update_key(trans, &iter, b, k.k, 0, false);
+                       if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) {
+                               ret = 0;
+                               continue;
+                       }
+
+                       bch_err_msg(c, ret, "updating btree node key");
+                       if (ret)
+                               break;
+next:
+                       bch2_btree_iter_next_node(&iter);
+               }
+               if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
+                       goto retry;
+
+               bch2_trans_iter_exit(trans, &iter);
+
+               if (ret)
+                       goto err;
+       }
+
+       bch2_btree_interior_updates_flush(c);
+       ret = 0;
+err:
+       bch2_bkey_buf_exit(&k, c);
+       bch2_trans_put(trans);
+
+       BUG_ON(bch2_err_matches(ret, BCH_ERR_transaction_restart));
+
+       return ret;
+}
+
+int bch2_dev_data_drop(struct bch_fs *c, unsigned dev_idx, int flags)
+{
+       return bch2_dev_usrdata_drop(c, dev_idx, flags) ?:
+               bch2_dev_metadata_drop(c, dev_idx, flags);
+}