path: root/fs/bcachefs/debug.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Assorted bcachefs debug code
 *
 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
 * Copyright 2012 Google, Inc.
 */

#include "bcachefs.h"
#include "bkey_methods.h"
#include "btree_cache.h"
#include "btree_io.h"
#include "btree_iter.h"
#include "btree_locking.h"
#include "btree_update.h"
#include "btree_update_interior.h"
#include "buckets.h"
#include "debug.h"
#include "error.h"
#include "extents.h"
#include "fsck.h"
#include "inode.h"
#include "super.h"

#include <linux/console.h>
#include <linux/debugfs.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/seq_file.h>

static struct dentry *bch_debug;

static bool bch2_btree_verify_replica(struct bch_fs *c, struct btree *b,
				      struct extent_ptr_decoded pick)
{
	struct btree *v = c->verify_data;
	struct btree_node *n_ondisk = c->verify_ondisk;
	struct btree_node *n_sorted = c->verify_data->data;
	struct bset *sorted, *inmemory = &b->data->keys;
	struct bio *bio;
	bool failed = false, saw_error = false;

	struct bch_dev *ca = bch2_dev_get_ioref(c, pick.ptr.dev, READ);
	if (!ca)
		return false;

	bio = bio_alloc_bioset(ca->disk_sb.bdev,
			       buf_pages(n_sorted, btree_buf_bytes(b)),
			       REQ_OP_READ|REQ_META,
			       GFP_NOFS,
			       &c->btree_bio);
	bio->bi_iter.bi_sector	= pick.ptr.offset;
	bch2_bio_map(bio, n_sorted, btree_buf_bytes(b));

	submit_bio_wait(bio);

	bio_put(bio);
	percpu_ref_put(&ca->io_ref);

	memcpy(n_ondisk, n_sorted, btree_buf_bytes(b));

	v->written = 0;
	if (bch2_btree_node_read_done(c, ca, v, false, &saw_error) || saw_error)
		return false;

	n_sorted = c->verify_data->data;
	sorted = &n_sorted->keys;

	if (inmemory->u64s != sorted->u64s ||
	    memcmp(inmemory->start,
		   sorted->start,
		   vstruct_end(inmemory) - (void *) inmemory->start)) {
		unsigned offset = 0, sectors;
		struct bset *i;
		unsigned j;

		console_lock();

		printk(KERN_ERR "*** in memory:\n");
		bch2_dump_bset(c, b, inmemory, 0);

		printk(KERN_ERR "*** read back in:\n");
		bch2_dump_bset(c, v, sorted, 0);

		while (offset < v->written) {
			if (!offset) {
				i = &n_ondisk->keys;
				sectors = vstruct_blocks(n_ondisk, c->block_bits) <<
					c->block_bits;
			} else {
				struct btree_node_entry *bne =
					(void *) n_ondisk + (offset << 9);
				i = &bne->keys;

				sectors = vstruct_blocks(bne, c->block_bits) <<
					c->block_bits;
			}

			printk(KERN_ERR "*** on disk block %u:\n", offset);
			bch2_dump_bset(c, b, i, offset);

			offset += sectors;
		}

		for (j = 0; j < le16_to_cpu(inmemory->u64s); j++)
			if (inmemory->_data[j] != sorted->_data[j])
				break;

		console_unlock();
		bch_err(c, "verify failed at key %u", j);

		failed = true;
	}

	if (v->written != b->written) {
		bch_err(c, "written wrong: expected %u, got %u",
			b->written, v->written);
		failed = true;
	}

	return failed;
}

void __bch2_btree_verify(struct bch_fs *c, struct btree *b)
{
	struct bkey_ptrs_c ptrs;
	struct extent_ptr_decoded p;
	const union bch_extent_entry *entry;
	struct btree *v;
	struct bset *inmemory = &b->data->keys;
	struct bkey_packed *k;
	bool failed = false;

	if (c->opts.nochanges)
		return;

	bch2_btree_node_io_lock(b);
	mutex_lock(&c->verify_lock);

	if (!c->verify_ondisk) {
		c->verify_ondisk = kvmalloc(btree_buf_bytes(b), GFP_KERNEL);
		if (!c->verify_ondisk)
			goto out;
	}

	if (!c->verify_data) {
		c->verify_data = __bch2_btree_node_mem_alloc(c);
		if (!c->verify_data)
			goto out;

		list_del_init(&c->verify_data->list);
	}

	BUG_ON(b->nsets != 1);

	for (k = inmemory->start; k != vstruct_last(inmemory); k = bkey_p_next(k))
		if (k->type == KEY_TYPE_btree_ptr_v2)
			((struct bch_btree_ptr_v2 *) bkeyp_val(&b->format, k))->mem_ptr = 0;

	v = c->verify_data;
	bkey_copy(&v->key, &b->key);
	v->c.level	= b->c.level;
	v->c.btree_id	= b->c.btree_id;
	bch2_btree_keys_init(v);

	ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(&b->key));
	bkey_for_each_ptr_decode(&b->key.k, ptrs, p, entry)
		failed |= bch2_btree_verify_replica(c, b, p);

	if (failed) {
		struct printbuf buf = PRINTBUF;

		bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
		bch2_fs_fatal_error(c, ": btree node verify fail