bcachefs: minor lru fsck fixes

check_lru_key() wasn't using write buffer updates for deleting bad lru
entries - dating from before the lru btree used the btree write buffer.

And when possibly flushing the btree write buffer (to make sure we're
seeing a real inconsistency), we need to be using the modern
bch2_btree_write_buffer_maybe_flush().

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

diff --git a/fs/bcachefs/lru.c b/fs/bcachefs/lru.c
index 96f2f4f8c39787e79fc5f831d9a12edd4f0dae95..dd5df668131a0dc759ff1bbd0dfa48119d1f554e 100644 (file)
--- a/fs/bcachefs/lru.c
+++ b/fs/bcachefs/lru.c
@@ -2,6 +2,7 @@
 
 #include "bcachefs.h"
 #include "alloc_background.h"
+#include "bkey_buf.h"
 #include "btree_iter.h"
 #include "btree_update.h"
 #include "btree_write_buffer.h"
@@ -118,7 +119,7 @@ fsck_err:
 static int bch2_check_lru_key(struct btree_trans *trans,
                              struct btree_iter *lru_iter,
                              struct bkey_s_c lru_k,
-                             struct bpos *last_flushed_pos)
+                             struct bkey_buf *last_flushed)
 {
        struct bch_fs *c = trans->c;
        struct btree_iter iter;
@@ -136,7 +137,7 @@ static int bch2_check_lru_key(struct btree_trans *trans,
                        trans, lru_entry_to_invalid_bucket,
                        "lru key points to nonexistent device:bucket %llu:%llu",
                        alloc_pos.inode, alloc_pos.offset))
-               return bch2_btree_delete_at(trans, lru_iter, 0);
+               return bch2_btree_bit_mod_buffered(trans, BTREE_ID_lru, lru_iter->pos, false);
 
        k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_alloc, alloc_pos, 0);
        ret = bkey_err(k);
@@ -156,12 +157,9 @@ static int bch2_check_lru_key(struct btree_trans *trans,
 
        if (lru_k.k->type != KEY_TYPE_set ||
            lru_pos_time(lru_k.k->p) != idx) {
-               if (!bpos_eq(*last_flushed_pos, lru_k.k->p)) {
-                       *last_flushed_pos = lru_k.k->p;
-                       ret = bch2_btree_write_buffer_flush_sync(trans) ?:
-                               -BCH_ERR_transaction_restart_write_buffer_flush;
-                       goto out;
-               }
+               ret = bch2_btree_write_buffer_maybe_flush(trans, lru_k, last_flushed);
+               if (ret)
+                       goto err;
 
                if (fsck_err(trans, lru_entry_bad,
                             "incorrect lru entry: lru %s time %llu\n"
@@ -171,9 +169,8 @@ static int bch2_check_lru_key(struct btree_trans *trans,
                             lru_pos_time(lru_k.k->p),
                             (bch2_bkey_val_to_text(&buf1, c, lru_k), buf1.buf),
                             (bch2_bkey_val_to_text(&buf2, c, k), buf2.buf)))
-                       ret = bch2_btree_delete_at(trans, lru_iter, 0);
+                       ret = bch2_btree_bit_mod_buffered(trans, BTREE_ID_lru, lru_iter->pos, false);
        }
-out:
 err:
 fsck_err:
        bch2_trans_iter_exit(trans, &iter);
@@ -184,12 +181,18 @@ fsck_err:
 
 int bch2_check_lrus(struct bch_fs *c)
 {
-       struct bpos last_flushed_pos = POS_MIN;
+       struct bkey_buf last_flushed;
+
+       bch2_bkey_buf_init(&last_flushed);
+       bkey_init(&last_flushed.k->k);
+
        int ret = bch2_trans_run(c,
                for_each_btree_key_commit(trans, iter,
                                BTREE_ID_lru, POS_MIN, BTREE_ITER_prefetch, k,
                                NULL, NULL, BCH_TRANS_COMMIT_no_enospc|BCH_TRANS_COMMIT_lazy_rw,
-                       bch2_check_lru_key(trans, &iter, k, &last_flushed_pos)));
+                       bch2_check_lru_key(trans, &iter, k, &last_flushed)));
+
+       bch2_bkey_buf_exit(&last_flushed, c);
        bch_err_fn(c, ret);
        return ret;