return ret < 0 ? ret : 0;
}
-static bool bch2_invalidate_one_bucket(struct bch_fs *c, struct bch_dev *ca,
- size_t bucket, u64 *flush_seq)
-{
- struct bucket_mark m;
-
- percpu_down_read(&c->mark_lock);
- spin_lock(&c->freelist_lock);
-
- bch2_invalidate_bucket(c, ca, bucket, &m);
-
- verify_not_on_freelist(c, ca, bucket);
- BUG_ON(!fifo_push(&ca->free_inc, bucket));
-
- spin_unlock(&c->freelist_lock);
-
- bucket_io_clock_reset(c, ca, bucket, READ);
- bucket_io_clock_reset(c, ca, bucket, WRITE);
-
- percpu_up_read(&c->mark_lock);
-
- *flush_seq = max(*flush_seq, bucket_journal_seq(c, m));
-
- return m.cached_sectors != 0;
-}
-
/*
* Pull buckets off ca->alloc_heap, invalidate them, move them to ca->free_inc:
*/
return 0;
}
-static bool flush_held_btree_writes(struct bch_fs *c)
-{
- struct bucket_table *tbl;
- struct rhash_head *pos;
- struct btree *b;
- bool nodes_unwritten;
- size_t i;
-again:
- cond_resched();
- nodes_unwritten = false;
-
- if (bch2_journal_error(&c->journal))
- return true;
-
- rcu_read_lock();
- for_each_cached_btree(b, c, tbl, i, pos)
- if (btree_node_need_write(b)) {
- if (btree_node_may_write(b)) {
- rcu_read_unlock();
- btree_node_lock_type(c, b, SIX_LOCK_read);
- bch2_btree_node_write(c, b, SIX_LOCK_read);
- six_unlock_read(&b->c.lock);
- goto again;
- } else {
- nodes_unwritten = true;
- }
- }
- rcu_read_unlock();
-
- return !nodes_unwritten &&
- !bch2_btree_interior_updates_nr_pending(c);
-}
-
-static void allocator_start_issue_discards(struct bch_fs *c)
-{
- struct bch_dev *ca;
- unsigned dev_iter;
- size_t bu;
-
- for_each_rw_member(ca, c, dev_iter)
- while (fifo_pop(&ca->free_inc, bu))
- blkdev_issue_discard(ca->disk_sb.bdev,
- bucket_to_sector(ca, bu),
- ca->mi.bucket_size, GFP_NOIO);
-}
-
-static int resize_free_inc(struct bch_dev *ca)
-{
- alloc_fifo free_inc;
-
- if (!fifo_full(&ca->free_inc))
- return 0;
-
- if (!init_fifo(&free_inc,
- ca->free_inc.size * 2,
- GFP_KERNEL))
- return -ENOMEM;
-
- fifo_move(&free_inc, &ca->free_inc);
- swap(free_inc, ca->free_inc);
- free_fifo(&free_inc);
- return 0;
-}
-
-static bool bch2_fs_allocator_start_fast(struct bch_fs *c)
-{
- struct bch_dev *ca;
- unsigned dev_iter;
- bool ret = true;
-
- if (test_alloc_startup(c))
- return false;
-
- down_read(&c->gc_lock);
-
- /* Scan for buckets that are already invalidated: */
- for_each_rw_member(ca, c, dev_iter) {
- struct bucket_array *buckets;
- struct bucket_mark m;
- long bu;
-
- down_read(&ca->bucket_lock);
- buckets = bucket_array(ca);
-
- for (bu = buckets->first_bucket;
- bu < buckets->nbuckets; bu++) {
- m = READ_ONCE(buckets->b[bu].mark);
-
- if (!buckets->b[bu].gen_valid ||
- !is_available_bucket(m) ||
- m.cached_sectors ||
- (ca->buckets_nouse &&
- test_bit(bu, ca->buckets_nouse)))
- continue;
-
- percpu_down_read(&c->mark_lock);
- bch2_mark_alloc_bucket(c, ca, bu, true,
- gc_pos_alloc(c, NULL), 0);
- percpu_up_read(&c->mark_lock);
-
- fifo_push(&ca->free_inc, bu);
-
- discard_invalidated_buckets(c, ca);
-
- if (fifo_full(&ca->free[RESERVE_BTREE]))
- break;
- }
- up_read(&ca->bucket_lock);
- }
-
- up_read(&c->gc_lock);
-
- /* did we find enough buckets? */
- for_each_rw_member(ca, c, dev_iter)
- if (!fifo_full(&ca->free[RESERVE_BTREE]))
- ret = false;
-
- return ret;
-}
-
-int bch2_fs_allocator_start(struct bch_fs *c)
-{
- struct bch_dev *ca;
- unsigned dev_iter;
- u64 journal_seq = 0;
- bool wrote;
- long bu;
- int ret = 0;
-
- if (!test_alloc_startup(c) &&
- bch2_fs_allocator_start_fast(c))
- return 0;
-
- pr_debug("not enough empty buckets; scanning for reclaimable buckets");
-
- /*
- * We're moving buckets to freelists _before_ they've been marked as
- * invalidated on disk - we have to so that we can allocate new btree
- * nodes to mark them as invalidated on disk.
- *
- * However, we can't _write_ to any of these buckets yet - they might
- * have cached data in them, which is live until they're marked as
- * invalidated on disk:
- */
- set_bit(BCH_FS_HOLD_BTREE_WRITES, &c->flags);
-
- down_read(&c->gc_lock);
- do {
- wrote = false;
-
- for_each_rw_member(ca, c, dev_iter) {
- find_reclaimable_buckets(c, ca);
-
- while (!fifo_full(&ca->free[RESERVE_BTREE]) &&
- (bu = next_alloc_bucket(ca)) >= 0) {
- ret = resize_free_inc(ca);
- if (ret) {
- percpu_ref_put(&ca->io_ref);
- up_read(&c->gc_lock);
- goto err;
- }
-
- bch2_invalidate_one_bucket(c, ca, bu,
- &journal_seq);
-
- fifo_push(&ca->free[RESERVE_BTREE], bu);
- }
- }
-
- pr_debug("done scanning for reclaimable buckets");
-
- /*
- * XXX: it's possible for this to deadlock waiting on journal reclaim,
- * since we're holding btree writes. What then?
- */
- ret = bch2_alloc_write(c,
- BTREE_INSERT_NOCHECK_RW|
- BTREE_INSERT_USE_ALLOC_RESERVE|
- BTREE_INSERT_NOWAIT, &wrote);
-
- /*
- * If bch2_alloc_write() did anything, it may have used some
- * buckets, and we need the RESERVE_BTREE freelist full - so we
- * need to loop and scan again.
- * And if it errored, it may have been because there weren't
- * enough buckets, so just scan and loop again as long as it
- * made some progress:
- */
- } while (wrote);
- up_read(&c->gc_lock);
-
- if (ret)
- goto err;
-
- pr_debug("flushing journal");
-
- ret = bch2_journal_flush(&c->journal);
- if (ret)
- goto err;
-
- pr_debug("issuing discards");
- allocator_start_issue_discards(c);
-err:
- clear_bit(BCH_FS_HOLD_BTREE_WRITES, &c->flags);
- closure_wait_event(&c->btree_interior_update_wait,
- flush_held_btree_writes(c));
-
- return ret;
-}
-
void bch2_fs_allocator_background_init(struct bch_fs *c)
{
spin_lock_init(&c->freelist_lock);
projects / linux-block.git / commitdiff