bcachefs: Fix for when compressed extent is split during journal replay

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

diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c
index db95257cec11a282b68c87d1906b0abdf02b105c..9997a2793e0a4d5c42b721143a2248ca2747dd07 100644 (file)
--- a/fs/bcachefs/journal_io.c
+++ b/fs/bcachefs/journal_io.c
@@ -823,6 +823,63 @@ fsck_err:
 
 /* journal replay: */
 
+static int bch2_extent_replay_key(struct bch_fs *c, struct bkey_i *k)
+{
+       /*
+        * We might cause compressed extents to be
+        * split, so we need to pass in a
+        * disk_reservation:
+        */
+       struct disk_reservation disk_res =
+               bch2_disk_reservation_init(c, 0);
+       BKEY_PADDED(k) split;
+       struct btree_iter iter;
+       int ret;
+
+       bch2_btree_iter_init(&iter, c, BTREE_ID_EXTENTS,
+                            bkey_start_pos(&k->k),
+                            BTREE_ITER_INTENT);
+       do {
+               ret = bch2_btree_iter_traverse(&iter);
+               if (ret)
+                       break;
+
+               bkey_copy(&split.k, k);
+               bch2_cut_front(iter.pos, &split.k);
+               bch2_extent_trim_atomic(&split.k, &iter);
+
+               ret = bch2_disk_reservation_add(c, &disk_res,
+                               split.k.k.size *
+                               bch2_bkey_nr_dirty_ptrs(bkey_i_to_s_c(&split.k)),
+                               BCH_DISK_RESERVATION_NOFAIL);
+               BUG_ON(ret);
+
+               ret = bch2_btree_insert_at(c, &disk_res, NULL,
+                                          BTREE_INSERT_ATOMIC|
+                                          BTREE_INSERT_NOFAIL|
+                                          BTREE_INSERT_JOURNAL_REPLAY,
+                                          BTREE_INSERT_ENTRY(&iter, &split.k));
+       } while ((!ret || ret == -EINTR) &&
+                bkey_cmp(k->k.p, iter.pos));
+
+       bch2_disk_reservation_put(c, &disk_res);
+
+       /*
+        * This isn't strictly correct - we should only be relying on the btree
+        * node lock for synchronization with gc when we've got a write lock
+        * held.
+        *
+        * but - there are other correctness issues if btree gc were to run
+        * before journal replay finishes
+        */
+       bch2_mark_key(c, bkey_i_to_s_c(k), false, -((s64) k->k.size),
+                     gc_pos_btree_node(iter.l[0].b),
+                     NULL, 0, 0);
+       bch2_btree_iter_unlock(&iter);
+
+       return ret;
+}
+
 int bch2_journal_replay(struct bch_fs *c, struct list_head *list)
 {
        struct journal *j = &c->journal;
@@ -835,27 +892,20 @@ int bch2_journal_replay(struct bch_fs *c, struct list_head *list)
                j->replay_journal_seq = le64_to_cpu(i->j.seq);
 
                for_each_jset_key(k, _n, entry, &i->j) {
-
-                       if (entry->btree_id == BTREE_ID_ALLOC) {
-                               /*
-                                * allocation code handles replay for
-                                * BTREE_ID_ALLOC keys:
-                                */
+                       switch (entry->btree_id) {
+                       case BTREE_ID_ALLOC:
                                ret = bch2_alloc_replay_key(c, k);
-                       } else {
-                               /*
-                                * We might cause compressed extents to be
-                                * split, so we need to pass in a
-                                * disk_reservation:
-                                */
-                               struct disk_reservation disk_res =
-                                       bch2_disk_reservation_init(c, 0);
-
+                               break;
+                       case BTREE_ID_EXTENTS:
+                               ret = bch2_extent_replay_key(c, k);
+                               break;
+                       default:
                                ret = bch2_btree_insert(c, entry->btree_id, k,
-                                               &disk_res, NULL,
+                                               NULL, NULL,
                                                BTREE_INSERT_NOFAIL|
                                                BTREE_INSERT_JOURNAL_REPLAY|
                                                BTREE_INSERT_NOMARK);
+                               break;
                        }
 
                        if (ret) {