path: root/fs/bcachefs/btree_trans_commit.c

// SPDX-License-Identifier: GPL-2.0

#include "bcachefs.h"
#include "alloc_foreground.h"
#include "btree_gc.h"
#include "btree_io.h"
#include "btree_iter.h"
#include "btree_journal_iter.h"
#include "btree_key_cache.h"
#include "btree_update_interior.h"
#include "btree_write_buffer.h"
#include "buckets.h"
#include "disk_accounting.h"
#include "enumerated_ref.h"
#include "errcode.h"
#include "error.h"
#include "journal.h"
#include "journal_io.h"
#include "journal_reclaim.h"
#include "replicas.h"
#include "snapshot.h"

#include <linux/prefetch.h>
#include <linux/string_helpers.h>

static const char * const trans_commit_flags_strs[] = {
#define x(n, ...) #n,
	BCH_TRANS_COMMIT_FLAGS()
#undef x
	NULL
};

void bch2_trans_commit_flags_to_text(struct printbuf *out, enum bch_trans_commit_flags flags)
{
	enum bch_watermark watermark = flags & BCH_WATERMARK_MASK;

	prt_printf(out, "watermark=%s", bch2_watermarks[watermark]);

	flags >>= BCH_WATERMARK_BITS;
	if (flags) {
		prt_char(out, ' ');
		bch2_prt_bitflags(out, trans_commit_flags_strs, flags);
	}
}

static void verify_update_old_key(struct btree_trans *trans, struct btree_insert_entry *i)
{
#ifdef CONFIG_BCACHEFS_DEBUG
	struct bch_fs *c = trans->c;
	struct bkey u;
	struct bkey_s_c k = bch2_btree_path_peek_slot_exact(trans->paths + i->path, &u);

	if (unlikely(trans->journal_replay_not_finished)) {
		struct bkey_i *j_k =
			bch2_journal_keys_peek_slot(c, i->btree_id, i->level, i->k->k.p);

		if (j_k)
			k = bkey_i_to_s_c(j_k);
	}

	u = *k.k;
	u.needs_whiteout = i->old_k.needs_whiteout;

	BUG_ON(memcmp(&i->old_k, &u, sizeof(struct bkey)));
	BUG_ON(i->old_v != k.v);
#endif
}

static inline struct btree_path_level *insert_l(struct btree_trans *trans, struct btree_insert_entry *i)
{
	return (trans->paths + i->path)->l + i->level;
}

static inline bool same_leaf_as_prev(struct btree_trans *trans,
				     struct btree_insert_entry *i)
{
	return i != trans->updates &&
		insert_l(trans, &i[0])->b == insert_l(trans, &i[-1])->b;
}

static inline bool same_leaf_as_next(struct btree_trans *trans,
				     struct btree_insert_entry *i)
{
	return i + 1 < trans->updates + trans->nr_updates &&
		insert_l(trans, &i[0])->b == insert_l(trans, &i[1])->b;
}

inline void bch2_btree_node_prep_for_write(struct btree_trans *trans,
					   struct btree_path *path,
					   struct btree *b)
{
	struct bch_fs *c = trans->c;

	if (unlikely(btree_node_just_written(b)) &&
	    bch2_btree_post_write_cleanup(c, b))
		bch2_trans_node_reinit_iter(trans, b);

	/*
	 * If the last bset has been written, or if it's gotten too big - start
	 * a new bset to insert into:
	 */
	if (want_new_bset(c, b))
		bch2_btree_init_next(trans, b);
}

static noinline int trans_lock_write_fail(struct btree_trans *trans, struct btree_insert_entry *i)
{
	while (--i >= trans->updates) {
		if (same_leaf_as_prev(trans, i))
			continue;

		bch2_btree_node_unlock_write(trans, trans->paths + i->path, insert_l(trans, i)->b);
	}

	trace_and_count(trans->c, trans_restart_would_deadlock_write, trans);
	return btree_trans_restart(trans, BCH_ERR_transaction_restart_would_deadlock_write);
}

static inline int bch2_trans_lock_write(struct btree_trans *trans)
{
	EBUG_ON(trans->write_locked);

	trans_for_each_update(trans, i) {
		if (same_leaf_as_prev(trans, i))
			continue;

		if (bch2_btree_node_lock_write(trans, trans->paths + i->path, &insert_l(trans, i)->b->c))
			return trans_lock_write_fail(trans, i);

		if (!i->cached)
			bch2_btree_node_prep_for_write