https://github.com/torvalds/linux
Tip revision: 92ed301919932f777713b9172e525674157e983d authored by Linus Torvalds on 26 July 2020, 21:14:06 UTC
Linux 5.8-rc7
Linux 5.8-rc7
Tip revision: 92ed301
debug.c
// SPDX-License-Identifier: GPL-2.0
/*
* Assorted bcache debug code
*
* Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
* Copyright 2012 Google, Inc.
*/
#include "bcache.h"
#include "btree.h"
#include "debug.h"
#include "extents.h"
#include <linux/console.h>
#include <linux/debugfs.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/seq_file.h>
struct dentry *bcache_debug;
#ifdef CONFIG_BCACHE_DEBUG
#define for_each_written_bset(b, start, i) \
for (i = (start); \
(void *) i < (void *) (start) + (KEY_SIZE(&b->key) << 9) &&\
i->seq == (start)->seq; \
i = (void *) i + set_blocks(i, block_bytes(b->c)) * \
block_bytes(b->c))
void bch_btree_verify(struct btree *b)
{
struct btree *v = b->c->verify_data;
struct bset *ondisk, *sorted, *inmemory;
struct bio *bio;
if (!b->c->verify || !b->c->verify_ondisk)
return;
down(&b->io_mutex);
mutex_lock(&b->c->verify_lock);
ondisk = b->c->verify_ondisk;
sorted = b->c->verify_data->keys.set->data;
inmemory = b->keys.set->data;
bkey_copy(&v->key, &b->key);
v->written = 0;
v->level = b->level;
v->keys.ops = b->keys.ops;
bio = bch_bbio_alloc(b->c);
bio_set_dev(bio, PTR_CACHE(b->c, &b->key, 0)->bdev);
bio->bi_iter.bi_sector = PTR_OFFSET(&b->key, 0);
bio->bi_iter.bi_size = KEY_SIZE(&v->key) << 9;
bio->bi_opf = REQ_OP_READ | REQ_META;
bch_bio_map(bio, sorted);
submit_bio_wait(bio);
bch_bbio_free(bio, b->c);
memcpy(ondisk, sorted, KEY_SIZE(&v->key) << 9);
bch_btree_node_read_done(v);
sorted = v->keys.set->data;
if (inmemory->keys != sorted->keys ||
memcmp(inmemory->start,
sorted->start,
(void *) bset_bkey_last(inmemory) -
(void *) inmemory->start)) {
struct bset *i;
unsigned int j;
console_lock();
pr_err("*** in memory:\n");
bch_dump_bset(&b->keys, inmemory, 0);
pr_err("*** read back in:\n");
bch_dump_bset(&v->keys, sorted, 0);
for_each_written_bset(b, ondisk, i) {
unsigned int block = ((void *) i - (void *) ondisk) /
block_bytes(b->c);
pr_err("*** on disk block %u:\n", block);
bch_dump_bset(&b->keys, i, block);
}
pr_err("*** block %zu not written\n",
((void *) i - (void *) ondisk) / block_bytes(b->c));
for (j = 0; j < inmemory->keys; j++)
if (inmemory->d[j] != sorted->d[j])
break;
pr_err("b->written %u\n", b->written);
console_unlock();
panic("verify failed at %u\n", j);
}
mutex_unlock(&b->c->verify_lock);
up(&b->io_mutex);
}
void bch_data_verify(struct cached_dev *dc, struct bio *bio)
{
struct bio *check;
struct bio_vec bv, cbv;
struct bvec_iter iter, citer = { 0 };
check = bio_kmalloc(GFP_NOIO, bio_segments(bio));
if (!check)
return;
check->bi_disk = bio->bi_disk;
check->bi_opf = REQ_OP_READ;
check->bi_iter.bi_sector = bio->bi_iter.bi_sector;
check->bi_iter.bi_size = bio->bi_iter.bi_size;
bch_bio_map(check, NULL);
if (bch_bio_alloc_pages(check, GFP_NOIO))
goto out_put;
submit_bio_wait(check);
citer.bi_size = UINT_MAX;
bio_for_each_segment(bv, bio, iter) {
void *p1 = kmap_atomic(bv.bv_page);
void *p2;
cbv = bio_iter_iovec(check, citer);
p2 = page_address(cbv.bv_page);
cache_set_err_on(memcmp(p1 + bv.bv_offset,
p2 + bv.bv_offset,
bv.bv_len),
dc->disk.c,
"verify failed at dev %s sector %llu",
dc->backing_dev_name,
(uint64_t) bio->bi_iter.bi_sector);
kunmap_atomic(p1);
bio_advance_iter(check, &citer, bv.bv_len);
}
bio_free_pages(check);
out_put:
bio_put(check);
}
#endif
#ifdef CONFIG_DEBUG_FS
/* XXX: cache set refcounting */
struct dump_iterator {
char buf[PAGE_SIZE];
size_t bytes;
struct cache_set *c;
struct keybuf keys;
};
static bool dump_pred(struct keybuf *buf, struct bkey *k)
{
return true;
}
static ssize_t bch_dump_read(struct file *file, char __user *buf,
size_t size, loff_t *ppos)
{
struct dump_iterator *i = file->private_data;
ssize_t ret = 0;
char kbuf[80];
while (size) {
struct keybuf_key *w;
unsigned int bytes = min(i->bytes, size);
if (copy_to_user(buf, i->buf, bytes))
return -EFAULT;
ret += bytes;
buf += bytes;
size -= bytes;
i->bytes -= bytes;
memmove(i->buf, i->buf + bytes, i->bytes);
if (i->bytes)
break;
w = bch_keybuf_next_rescan(i->c, &i->keys, &MAX_KEY, dump_pred);
if (!w)
break;
bch_extent_to_text(kbuf, sizeof(kbuf), &w->key);
i->bytes = snprintf(i->buf, PAGE_SIZE, "%s\n", kbuf);
bch_keybuf_del(&i->keys, w);
}
return ret;
}
static int bch_dump_open(struct inode *inode, struct file *file)
{
struct cache_set *c = inode->i_private;
struct dump_iterator *i;
i = kzalloc(sizeof(struct dump_iterator), GFP_KERNEL);
if (!i)
return -ENOMEM;
file->private_data = i;
i->c = c;
bch_keybuf_init(&i->keys);
i->keys.last_scanned = KEY(0, 0, 0);
return 0;
}
static int bch_dump_release(struct inode *inode, struct file *file)
{
kfree(file->private_data);
return 0;
}
static const struct file_operations cache_set_debug_ops = {
.owner = THIS_MODULE,
.open = bch_dump_open,
.read = bch_dump_read,
.release = bch_dump_release
};
void bch_debug_init_cache_set(struct cache_set *c)
{
if (!IS_ERR_OR_NULL(bcache_debug)) {
char name[50];
snprintf(name, 50, "bcache-%pU", c->sb.set_uuid);
c->debug = debugfs_create_file(name, 0400, bcache_debug, c,
&cache_set_debug_ops);
}
}
#endif
void bch_debug_exit(void)
{
debugfs_remove_recursive(bcache_debug);
}
void __init bch_debug_init(void)
{
/*
* it is unnecessary to check return value of
* debugfs_create_file(), we should not care
* about this.
*/
bcache_debug = debugfs_create_dir("bcache", NULL);
}