Merge tag 'bcachefs-2024-06-12' of https://evilpiepirate.org/git/bcachefs

Pull bcachefs fixes from Kent Overstreet:

 - fix kworker explosion, due to calling submit_bio() (which can block)
   from a multithreaded workqueue

 - fix error handling in btree node scan

 - forward compat fix: kill an old debug assert

 - key cache shrinker fixes

   This is a partial fix for stalls doing multithreaded creates - there
   were various O(n^2) issues the key cache shrinker was hitting [1].

   There's more work coming here; I'm working on a patch to delete the
   key cache lock, which initial testing shows to be a pretty drastic
   performance improvement

 - assorted syzbot fixes

Link: https://lore.kernel.org/linux-bcachefs/CAGudoHGenxzk0ZqPXXi1_QDbfqQhGHu+wUwzyS6WmfkUZ1HiXA@mail.gmail.com/ [1]

* tag 'bcachefs-2024-06-12' of https://evilpiepirate.org/git/bcachefs:
  bcachefs: Fix rcu_read_lock() leak in drop_extra_replicas
  bcachefs: Add missing bch_inode_info.ei_flags init
  bcachefs: Add missing synchronize_srcu_expedited() call when shutting down
  bcachefs: Check for invalid bucket from bucket_gen(), gc_bucket()
  bcachefs: Replace bucket_valid() asserts in bucket lookup with proper checks
  bcachefs: Fix snapshot_create_lock lock ordering
  bcachefs: Fix refcount leak in check_fix_ptrs()
  bcachefs: Leave a buffer in the btree key cache to avoid lock thrashing
  bcachefs: Fix reporting of freed objects from key cache shrinker
  bcachefs: set sb->s_shrinker->seeks = 0
  bcachefs: increase key cache shrinker batch size
  bcachefs: Enable automatic shrinking for rhashtables
  bcachefs: fix the display format for show-super
  bcachefs: fix stack frame size in fsck.c
  bcachefs: Delete incorrect BTREE_ID_NR assertion
  bcachefs: Fix incorrect error handling found_btree_node_is_readable()
  bcachefs: Split out btree_write_submit_wq

1 files changed, 15 insertions, 4 deletions

diff --git a/fs/bcachefs/io_write.c b/fs/bcachefs/io_write.c
index 9401d13e31bb..05e0cbef420b 100644
--- a/fs/bcachefs/io_write.c
+++ b/fs/bcachefs/io_write.c
@@ -1220,7 +1220,7 @@ static void bch2_nocow_write(struct bch_write_op *op)
 	DARRAY_PREALLOCATED(struct bucket_to_lock, 3) buckets;
 	u32 snapshot;
 	struct bucket_to_lock *stale_at;
-	int ret;
+	int stale, ret;
 
 	if (op->flags & BCH_WRITE_MOVE)
 		return;
@@ -1299,7 +1299,8 @@ retry:
 						 BUCKET_NOCOW_LOCK_UPDATE);
 
 			rcu_read_lock();
-			bool stale = gen_after(*bucket_gen(ca, i->b.offset), i->gen);
+			u8 *gen = bucket_gen(ca, i->b.offset);
+			stale = !gen ? -1 : gen_after(*gen, i->gen);
 			rcu_read_unlock();
 
 			if (unlikely(stale)) {
@@ -1380,8 +1381,18 @@ err_bucket_stale:
 			break;
 	}
 
-	/* We can retry this: */
-	ret = -BCH_ERR_transaction_restart;
+	struct printbuf buf = PRINTBUF;
+	if (bch2_fs_inconsistent_on(stale < 0, c,
+				    "pointer to invalid bucket in nocow path on device %llu\n  %s",
+				    stale_at->b.inode,
+				    (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
+		ret = -EIO;
+	} else {
+		/* We can retry this: */
+		ret = -BCH_ERR_transaction_restart;
+	}
+	printbuf_exit(&buf);
+
 	goto err_get_ioref;
 }