xref: /linux/fs/bcachefs/debug.c (revision 8080ff5ac656b9ca6c282e4044be19d2b8a837df)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Assorted bcachefs debug code
4  *
5  * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
6  * Copyright 2012 Google, Inc.
7  */
8 
9 #include "bcachefs.h"
10 #include "bkey_methods.h"
11 #include "btree_cache.h"
12 #include "btree_io.h"
13 #include "btree_iter.h"
14 #include "btree_locking.h"
15 #include "btree_update.h"
16 #include "btree_update_interior.h"
17 #include "buckets.h"
18 #include "debug.h"
19 #include "error.h"
20 #include "extents.h"
21 #include "fsck.h"
22 #include "inode.h"
23 #include "journal_reclaim.h"
24 #include "super.h"
25 
26 #include <linux/console.h>
27 #include <linux/debugfs.h>
28 #include <linux/module.h>
29 #include <linux/random.h>
30 #include <linux/seq_file.h>
31 
32 static struct dentry *bch_debug;
33 
bch2_btree_verify_replica(struct bch_fs * c,struct btree * b,struct extent_ptr_decoded pick)34 static bool bch2_btree_verify_replica(struct bch_fs *c, struct btree *b,
35 				      struct extent_ptr_decoded pick)
36 {
37 	struct btree *v = c->verify_data;
38 	struct btree_node *n_ondisk = c->verify_ondisk;
39 	struct btree_node *n_sorted = c->verify_data->data;
40 	struct bset *sorted, *inmemory = &b->data->keys;
41 	struct bio *bio;
42 	bool failed = false, saw_error = false;
43 
44 	struct bch_dev *ca = bch2_dev_get_ioref(c, pick.ptr.dev, READ);
45 	if (!ca)
46 		return false;
47 
48 	bio = bio_alloc_bioset(ca->disk_sb.bdev,
49 			       buf_pages(n_sorted, btree_buf_bytes(b)),
50 			       REQ_OP_READ|REQ_META,
51 			       GFP_NOFS,
52 			       &c->btree_bio);
53 	bio->bi_iter.bi_sector	= pick.ptr.offset;
54 	bch2_bio_map(bio, n_sorted, btree_buf_bytes(b));
55 
56 	submit_bio_wait(bio);
57 
58 	bio_put(bio);
59 	percpu_ref_put(&ca->io_ref);
60 
61 	memcpy(n_ondisk, n_sorted, btree_buf_bytes(b));
62 
63 	v->written = 0;
64 	if (bch2_btree_node_read_done(c, ca, v, false, &saw_error) || saw_error)
65 		return false;
66 
67 	n_sorted = c->verify_data->data;
68 	sorted = &n_sorted->keys;
69 
70 	if (inmemory->u64s != sorted->u64s ||
71 	    memcmp(inmemory->start,
72 		   sorted->start,
73 		   vstruct_end(inmemory) - (void *) inmemory->start)) {
74 		unsigned offset = 0, sectors;
75 		struct bset *i;
76 		unsigned j;
77 
78 		console_lock();
79 
80 		printk(KERN_ERR "*** in memory:\n");
81 		bch2_dump_bset(c, b, inmemory, 0);
82 
83 		printk(KERN_ERR "*** read back in:\n");
84 		bch2_dump_bset(c, v, sorted, 0);
85 
86 		while (offset < v->written) {
87 			if (!offset) {
88 				i = &n_ondisk->keys;
89 				sectors = vstruct_blocks(n_ondisk, c->block_bits) <<
90 					c->block_bits;
91 			} else {
92 				struct btree_node_entry *bne =
93 					(void *) n_ondisk + (offset << 9);
94 				i = &bne->keys;
95 
96 				sectors = vstruct_blocks(bne, c->block_bits) <<
97 					c->block_bits;
98 			}
99 
100 			printk(KERN_ERR "*** on disk block %u:\n", offset);
101 			bch2_dump_bset(c, b, i, offset);
102 
103 			offset += sectors;
104 		}
105 
106 		for (j = 0; j < le16_to_cpu(inmemory->u64s); j++)
107 			if (inmemory->_data[j] != sorted->_data[j])
108 				break;
109 
110 		console_unlock();
111 		bch_err(c, "verify failed at key %u", j);
112 
113 		failed = true;
114 	}
115 
116 	if (v->written != b->written) {
117 		bch_err(c, "written wrong: expected %u, got %u",
118 			b->written, v->written);
119 		failed = true;
120 	}
121 
122 	return failed;
123 }
124 
__bch2_btree_verify(struct bch_fs * c,struct btree * b)125 void __bch2_btree_verify(struct bch_fs *c, struct btree *b)
126 {
127 	struct bkey_ptrs_c ptrs;
128 	struct extent_ptr_decoded p;
129 	const union bch_extent_entry *entry;
130 	struct btree *v;
131 	struct bset *inmemory = &b->data->keys;
132 	struct bkey_packed *k;
133 	bool failed = false;
134 
135 	if (c->opts.nochanges)
136 		return;
137 
138 	bch2_btree_node_io_lock(b);
139 	mutex_lock(&c->verify_lock);
140 
141 	if (!c->verify_ondisk) {
142 		c->verify_ondisk = kvmalloc(btree_buf_bytes(b), GFP_KERNEL);
143 		if (!c->verify_ondisk)
144 			goto out;
145 	}
146 
147 	if (!c->verify_data) {
148 		c->verify_data = __bch2_btree_node_mem_alloc(c);
149 		if (!c->verify_data)
150 			goto out;
151 
152 		list_del_init(&c->verify_data->list);
153 	}
154 
155 	BUG_ON(b->nsets != 1);
156 
157 	for (k = inmemory->start; k != vstruct_last(inmemory); k = bkey_p_next(k))
158 		if (k->type == KEY_TYPE_btree_ptr_v2)
159 			((struct bch_btree_ptr_v2 *) bkeyp_val(&b->format, k))->mem_ptr = 0;
160 
161 	v = c->verify_data;
162 	bkey_copy(&v->key, &b->key);
163 	v->c.level	= b->c.level;
164 	v->c.btree_id	= b->c.btree_id;
165 	bch2_btree_keys_init(v);
166 
167 	ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(&b->key));
168 	bkey_for_each_ptr_decode(&b->key.k, ptrs, p, entry)
169 		failed |= bch2_btree_verify_replica(c, b, p);
170 
171 	if (failed) {
172 		struct printbuf buf = PRINTBUF;
173 
174 		bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
175 		bch2_fs_fatal_error(c, ": btree node verify failed for: %s\n", buf.buf);
176 		printbuf_exit(&buf);
177 	}
178 out:
179 	mutex_unlock(&c->verify_lock);
180 	bch2_btree_node_io_unlock(b);
181 }
182 
bch2_btree_node_ondisk_to_text(struct printbuf * out,struct bch_fs * c,const struct btree * b)183 void bch2_btree_node_ondisk_to_text(struct printbuf *out, struct bch_fs *c,
184 				    const struct btree *b)
185 {
186 	struct btree_node *n_ondisk = NULL;
187 	struct extent_ptr_decoded pick;
188 	struct bch_dev *ca;
189 	struct bio *bio = NULL;
190 	unsigned offset = 0;
191 	int ret;
192 
193 	if (bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key), NULL, &pick) <= 0) {
194 		prt_printf(out, "error getting device to read from: invalid device\n");
195 		return;
196 	}
197 
198 	ca = bch2_dev_get_ioref(c, pick.ptr.dev, READ);
199 	if (!ca) {
200 		prt_printf(out, "error getting device to read from: not online\n");
201 		return;
202 	}
203 
204 	n_ondisk = kvmalloc(btree_buf_bytes(b), GFP_KERNEL);
205 	if (!n_ondisk) {
206 		prt_printf(out, "memory allocation failure\n");
207 		goto out;
208 	}
209 
210 	bio = bio_alloc_bioset(ca->disk_sb.bdev,
211 			       buf_pages(n_ondisk, btree_buf_bytes(b)),
212 			       REQ_OP_READ|REQ_META,
213 			       GFP_NOFS,
214 			       &c->btree_bio);
215 	bio->bi_iter.bi_sector	= pick.ptr.offset;
216 	bch2_bio_map(bio, n_ondisk, btree_buf_bytes(b));
217 
218 	ret = submit_bio_wait(bio);
219 	if (ret) {
220 		prt_printf(out, "IO error reading btree node: %s\n", bch2_err_str(ret));
221 		goto out;
222 	}
223 
224 	while (offset < btree_sectors(c)) {
225 		struct bset *i;
226 		struct nonce nonce;
227 		struct bch_csum csum;
228 		struct bkey_packed *k;
229 		unsigned sectors;
230 
231 		if (!offset) {
232 			i = &n_ondisk->keys;
233 
234 			if (!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i))) {
235 				prt_printf(out, "unknown checksum type at offset %u: %llu\n",
236 					   offset, BSET_CSUM_TYPE(i));
237 				goto out;
238 			}
239 
240 			nonce = btree_nonce(i, offset << 9);
241 			csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, n_ondisk);
242 
243 			if (bch2_crc_cmp(csum, n_ondisk->csum)) {
244 				prt_printf(out, "invalid checksum\n");
245 				goto out;
246 			}
247 
248 			bset_encrypt(c, i, offset << 9);
249 
250 			sectors = vstruct_sectors(n_ondisk, c->block_bits);
251 		} else {
252 			struct btree_node_entry *bne = (void *) n_ondisk + (offset << 9);
253 
254 			i = &bne->keys;
255 
256 			if (i->seq != n_ondisk->keys.seq)
257 				break;
258 
259 			if (!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i))) {
260 				prt_printf(out, "unknown checksum type at offset %u: %llu\n",
261 					   offset, BSET_CSUM_TYPE(i));
262 				goto out;
263 			}
264 
265 			nonce = btree_nonce(i, offset << 9);
266 			csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bne);
267 
268 			if (bch2_crc_cmp(csum, bne->csum)) {
269 				prt_printf(out, "invalid checksum");
270 				goto out;
271 			}
272 
273 			bset_encrypt(c, i, offset << 9);
274 
275 			sectors = vstruct_sectors(bne, c->block_bits);
276 		}
277 
278 		prt_printf(out, "  offset %u version %u, journal seq %llu\n",
279 			   offset,
280 			   le16_to_cpu(i->version),
281 			   le64_to_cpu(i->journal_seq));
282 		offset += sectors;
283 
284 		printbuf_indent_add(out, 4);
285 
286 		for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k)) {
287 			struct bkey u;
288 
289 			bch2_bkey_val_to_text(out, c, bkey_disassemble(b, k, &u));
290 			prt_newline(out);
291 		}
292 
293 		printbuf_indent_sub(out, 4);
294 	}
295 out:
296 	if (bio)
297 		bio_put(bio);
298 	kvfree(n_ondisk);
299 	percpu_ref_put(&ca->io_ref);
300 }
301 
302 #ifdef CONFIG_DEBUG_FS
303 
304 /* XXX: bch_fs refcounting */
305 
306 struct dump_iter {
307 	struct bch_fs		*c;
308 	enum btree_id		id;
309 	struct bpos		from;
310 	struct bpos		prev_node;
311 	u64			iter;
312 
313 	struct printbuf		buf;
314 
315 	char __user		*ubuf;	/* destination user buffer */
316 	size_t			size;	/* size of requested read */
317 	ssize_t			ret;	/* bytes read so far */
318 };
319 
flush_buf(struct dump_iter * i)320 static ssize_t flush_buf(struct dump_iter *i)
321 {
322 	if (i->buf.pos) {
323 		size_t bytes = min_t(size_t, i->buf.pos, i->size);
324 		int copied = bytes - copy_to_user(i->ubuf, i->buf.buf, bytes);
325 
326 		i->ret	 += copied;
327 		i->ubuf	 += copied;
328 		i->size	 -= copied;
329 		i->buf.pos -= copied;
330 		memmove(i->buf.buf, i->buf.buf + copied, i->buf.pos);
331 
332 		if (copied != bytes)
333 			return -EFAULT;
334 	}
335 
336 	return i->size ? 0 : i->ret;
337 }
338 
bch2_dump_open(struct inode * inode,struct file * file)339 static int bch2_dump_open(struct inode *inode, struct file *file)
340 {
341 	struct btree_debug *bd = inode->i_private;
342 	struct dump_iter *i;
343 
344 	i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
345 	if (!i)
346 		return -ENOMEM;
347 
348 	file->private_data = i;
349 	i->from = POS_MIN;
350 	i->iter	= 0;
351 	i->c	= container_of(bd, struct bch_fs, btree_debug[bd->id]);
352 	i->id	= bd->id;
353 	i->buf	= PRINTBUF;
354 
355 	return 0;
356 }
357 
bch2_dump_release(struct inode * inode,struct file * file)358 static int bch2_dump_release(struct inode *inode, struct file *file)
359 {
360 	struct dump_iter *i = file->private_data;
361 
362 	printbuf_exit(&i->buf);
363 	kfree(i);
364 	return 0;
365 }
366 
bch2_read_btree(struct file * file,char __user * buf,size_t size,loff_t * ppos)367 static ssize_t bch2_read_btree(struct file *file, char __user *buf,
368 			       size_t size, loff_t *ppos)
369 {
370 	struct dump_iter *i = file->private_data;
371 
372 	i->ubuf = buf;
373 	i->size	= size;
374 	i->ret	= 0;
375 
376 	return flush_buf(i) ?:
377 		bch2_trans_run(i->c,
378 			for_each_btree_key(trans, iter, i->id, i->from,
379 					   BTREE_ITER_prefetch|
380 					   BTREE_ITER_all_snapshots, k, ({
381 				bch2_bkey_val_to_text(&i->buf, i->c, k);
382 				prt_newline(&i->buf);
383 				bch2_trans_unlock(trans);
384 				i->from = bpos_successor(iter.pos);
385 				flush_buf(i);
386 			}))) ?:
387 		i->ret;
388 }
389 
390 static const struct file_operations btree_debug_ops = {
391 	.owner		= THIS_MODULE,
392 	.open		= bch2_dump_open,
393 	.release	= bch2_dump_release,
394 	.read		= bch2_read_btree,
395 };
396 
bch2_read_btree_formats(struct file * file,char __user * buf,size_t size,loff_t * ppos)397 static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
398 				       size_t size, loff_t *ppos)
399 {
400 	struct dump_iter *i = file->private_data;
401 
402 	i->ubuf = buf;
403 	i->size	= size;
404 	i->ret	= 0;
405 
406 	ssize_t ret = flush_buf(i);
407 	if (ret)
408 		return ret;
409 
410 	if (bpos_eq(SPOS_MAX, i->from))
411 		return i->ret;
412 
413 	return bch2_trans_run(i->c,
414 		for_each_btree_node(trans, iter, i->id, i->from, 0, b, ({
415 			bch2_btree_node_to_text(&i->buf, i->c, b);
416 			i->from = !bpos_eq(SPOS_MAX, b->key.k.p)
417 				? bpos_successor(b->key.k.p)
418 				: b->key.k.p;
419 
420 			drop_locks_do(trans, flush_buf(i));
421 		}))) ?: i->ret;
422 }
423 
424 static const struct file_operations btree_format_debug_ops = {
425 	.owner		= THIS_MODULE,
426 	.open		= bch2_dump_open,
427 	.release	= bch2_dump_release,
428 	.read		= bch2_read_btree_formats,
429 };
430 
bch2_read_bfloat_failed(struct file * file,char __user * buf,size_t size,loff_t * ppos)431 static ssize_t bch2_read_bfloat_failed(struct file *file, char __user *buf,
432 				       size_t size, loff_t *ppos)
433 {
434 	struct dump_iter *i = file->private_data;
435 
436 	i->ubuf = buf;
437 	i->size	= size;
438 	i->ret	= 0;
439 
440 	return flush_buf(i) ?:
441 		bch2_trans_run(i->c,
442 			for_each_btree_key(trans, iter, i->id, i->from,
443 					   BTREE_ITER_prefetch|
444 					   BTREE_ITER_all_snapshots, k, ({
445 				struct btree_path_level *l =
446 					&btree_iter_path(trans, &iter)->l[0];
447 				struct bkey_packed *_k =
448 					bch2_btree_node_iter_peek(&l->iter, l->b);
449 
450 				if (bpos_gt(l->b->key.k.p, i->prev_node)) {
451 					bch2_btree_node_to_text(&i->buf, i->c, l->b);
452 					i->prev_node = l->b->key.k.p;
453 				}
454 
455 				bch2_bfloat_to_text(&i->buf, l->b, _k);
456 				bch2_trans_unlock(trans);
457 				i->from = bpos_successor(iter.pos);
458 				flush_buf(i);
459 			}))) ?:
460 		i->ret;
461 }
462 
463 static const struct file_operations bfloat_failed_debug_ops = {
464 	.owner		= THIS_MODULE,
465 	.open		= bch2_dump_open,
466 	.release	= bch2_dump_release,
467 	.read		= bch2_read_bfloat_failed,
468 };
469 
bch2_cached_btree_node_to_text(struct printbuf * out,struct bch_fs * c,struct btree * b)470 static void bch2_cached_btree_node_to_text(struct printbuf *out, struct bch_fs *c,
471 					   struct btree *b)
472 {
473 	if (!out->nr_tabstops)
474 		printbuf_tabstop_push(out, 32);
475 
476 	prt_printf(out, "%px ", b);
477 	bch2_btree_id_level_to_text(out, b->c.btree_id, b->c.level);
478 	prt_printf(out, "\n");
479 
480 	printbuf_indent_add(out, 2);
481 
482 	bch2_bkey_val_to_text(out, c, bkey_i_to_s_c(&b->key));
483 	prt_newline(out);
484 
485 	prt_printf(out, "flags:\t");
486 	prt_bitflags(out, bch2_btree_node_flags, b->flags);
487 	prt_newline(out);
488 
489 	prt_printf(out, "pcpu read locks:\t%u\n",	b->c.lock.readers != NULL);
490 	prt_printf(out, "written:\t%u\n",		b->written);
491 	prt_printf(out, "writes blocked:\t%u\n",	!list_empty_careful(&b->write_blocked));
492 	prt_printf(out, "will make reachable:\t%lx\n",	b->will_make_reachable);
493 
494 	prt_printf(out, "journal pin %px:\t%llu\n",
495 		   &b->writes[0].journal, b->writes[0].journal.seq);
496 	prt_printf(out, "journal pin %px:\t%llu\n",
497 		   &b->writes[1].journal, b->writes[1].journal.seq);
498 
499 	printbuf_indent_sub(out, 2);
500 }
501 
bch2_cached_btree_nodes_read(struct file * file,char __user * buf,size_t size,loff_t * ppos)502 static ssize_t bch2_cached_btree_nodes_read(struct file *file, char __user *buf,
503 					    size_t size, loff_t *ppos)
504 {
505 	struct dump_iter *i = file->private_data;
506 	struct bch_fs *c = i->c;
507 	bool done = false;
508 	ssize_t ret = 0;
509 
510 	i->ubuf = buf;
511 	i->size	= size;
512 	i->ret	= 0;
513 
514 	do {
515 		struct bucket_table *tbl;
516 		struct rhash_head *pos;
517 		struct btree *b;
518 
519 		ret = flush_buf(i);
520 		if (ret)
521 			return ret;
522 
523 		rcu_read_lock();
524 		i->buf.atomic++;
525 		tbl = rht_dereference_rcu(c->btree_cache.table.tbl,
526 					  &c->btree_cache.table);
527 		if (i->iter < tbl->size) {
528 			rht_for_each_entry_rcu(b, pos, tbl, i->iter, hash)
529 				bch2_cached_btree_node_to_text(&i->buf, c, b);
530 			i->iter++;
531 		} else {
532 			done = true;
533 		}
534 		--i->buf.atomic;
535 		rcu_read_unlock();
536 	} while (!done);
537 
538 	if (i->buf.allocation_failure)
539 		ret = -ENOMEM;
540 
541 	if (!ret)
542 		ret = flush_buf(i);
543 
544 	return ret ?: i->ret;
545 }
546 
547 static const struct file_operations cached_btree_nodes_ops = {
548 	.owner		= THIS_MODULE,
549 	.open		= bch2_dump_open,
550 	.release	= bch2_dump_release,
551 	.read		= bch2_cached_btree_nodes_read,
552 };
553 
554 typedef int (*list_cmp_fn)(const struct list_head *l, const struct list_head *r);
555 
list_sort(struct list_head * head,list_cmp_fn cmp)556 static void list_sort(struct list_head *head, list_cmp_fn cmp)
557 {
558 	struct list_head *pos;
559 
560 	list_for_each(pos, head)
561 		while (!list_is_last(pos, head) &&
562 		       cmp(pos, pos->next) > 0) {
563 			struct list_head *pos2, *next = pos->next;
564 
565 			list_del(next);
566 			list_for_each(pos2, head)
567 				if (cmp(next, pos2) < 0)
568 					goto pos_found;
569 			BUG();
570 pos_found:
571 			list_add_tail(next, pos2);
572 		}
573 }
574 
list_ptr_order_cmp(const struct list_head * l,const struct list_head * r)575 static int list_ptr_order_cmp(const struct list_head *l, const struct list_head *r)
576 {
577 	return cmp_int(l, r);
578 }
579 
bch2_btree_transactions_read(struct file * file,char __user * buf,size_t size,loff_t * ppos)580 static ssize_t bch2_btree_transactions_read(struct file *file, char __user *buf,
581 					    size_t size, loff_t *ppos)
582 {
583 	struct dump_iter *i = file->private_data;
584 	struct bch_fs *c = i->c;
585 	struct btree_trans *trans;
586 	ssize_t ret = 0;
587 
588 	i->ubuf = buf;
589 	i->size	= size;
590 	i->ret	= 0;
591 restart:
592 	seqmutex_lock(&c->btree_trans_lock);
593 	list_sort(&c->btree_trans_list, list_ptr_order_cmp);
594 
595 	list_for_each_entry(trans, &c->btree_trans_list, list) {
596 		if ((ulong) trans <= i->iter)
597 			continue;
598 
599 		i->iter = (ulong) trans;
600 
601 		if (!closure_get_not_zero(&trans->ref))
602 			continue;
603 
604 		u32 seq = seqmutex_unlock(&c->btree_trans_lock);
605 
606 		bch2_btree_trans_to_text(&i->buf, trans);
607 
608 		prt_printf(&i->buf, "backtrace:\n");
609 		printbuf_indent_add(&i->buf, 2);
610 		bch2_prt_task_backtrace(&i->buf, trans->locking_wait.task, 0, GFP_KERNEL);
611 		printbuf_indent_sub(&i->buf, 2);
612 		prt_newline(&i->buf);
613 
614 		closure_put(&trans->ref);
615 
616 		ret = flush_buf(i);
617 		if (ret)
618 			goto unlocked;
619 
620 		if (!seqmutex_relock(&c->btree_trans_lock, seq))
621 			goto restart;
622 	}
623 	seqmutex_unlock(&c->btree_trans_lock);
624 unlocked:
625 	if (i->buf.allocation_failure)
626 		ret = -ENOMEM;
627 
628 	if (!ret)
629 		ret = flush_buf(i);
630 
631 	return ret ?: i->ret;
632 }
633 
634 static const struct file_operations btree_transactions_ops = {
635 	.owner		= THIS_MODULE,
636 	.open		= bch2_dump_open,
637 	.release	= bch2_dump_release,
638 	.read		= bch2_btree_transactions_read,
639 };
640 
bch2_journal_pins_read(struct file * file,char __user * buf,size_t size,loff_t * ppos)641 static ssize_t bch2_journal_pins_read(struct file *file, char __user *buf,
642 				      size_t size, loff_t *ppos)
643 {
644 	struct dump_iter *i = file->private_data;
645 	struct bch_fs *c = i->c;
646 	bool done = false;
647 	int err;
648 
649 	i->ubuf = buf;
650 	i->size	= size;
651 	i->ret	= 0;
652 
653 	while (1) {
654 		err = flush_buf(i);
655 		if (err)
656 			return err;
657 
658 		if (!i->size)
659 			break;
660 
661 		if (done)
662 			break;
663 
664 		done = bch2_journal_seq_pins_to_text(&i->buf, &c->journal, &i->iter);
665 		i->iter++;
666 	}
667 
668 	if (i->buf.allocation_failure)
669 		return -ENOMEM;
670 
671 	return i->ret;
672 }
673 
674 static const struct file_operations journal_pins_ops = {
675 	.owner		= THIS_MODULE,
676 	.open		= bch2_dump_open,
677 	.release	= bch2_dump_release,
678 	.read		= bch2_journal_pins_read,
679 };
680 
bch2_btree_updates_read(struct file * file,char __user * buf,size_t size,loff_t * ppos)681 static ssize_t bch2_btree_updates_read(struct file *file, char __user *buf,
682 				       size_t size, loff_t *ppos)
683 {
684 	struct dump_iter *i = file->private_data;
685 	struct bch_fs *c = i->c;
686 	int err;
687 
688 	i->ubuf = buf;
689 	i->size	= size;
690 	i->ret	= 0;
691 
692 	if (!i->iter) {
693 		bch2_btree_updates_to_text(&i->buf, c);
694 		i->iter++;
695 	}
696 
697 	err = flush_buf(i);
698 	if (err)
699 		return err;
700 
701 	if (i->buf.allocation_failure)
702 		return -ENOMEM;
703 
704 	return i->ret;
705 }
706 
707 static const struct file_operations btree_updates_ops = {
708 	.owner		= THIS_MODULE,
709 	.open		= bch2_dump_open,
710 	.release	= bch2_dump_release,
711 	.read		= bch2_btree_updates_read,
712 };
713 
btree_transaction_stats_open(struct inode * inode,struct file * file)714 static int btree_transaction_stats_open(struct inode *inode, struct file *file)
715 {
716 	struct bch_fs *c = inode->i_private;
717 	struct dump_iter *i;
718 
719 	i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
720 	if (!i)
721 		return -ENOMEM;
722 
723 	i->iter = 1;
724 	i->c    = c;
725 	i->buf  = PRINTBUF;
726 	file->private_data = i;
727 
728 	return 0;
729 }
730 
btree_transaction_stats_release(struct inode * inode,struct file * file)731 static int btree_transaction_stats_release(struct inode *inode, struct file *file)
732 {
733 	struct dump_iter *i = file->private_data;
734 
735 	printbuf_exit(&i->buf);
736 	kfree(i);
737 
738 	return 0;
739 }
740 
btree_transaction_stats_read(struct file * file,char __user * buf,size_t size,loff_t * ppos)741 static ssize_t btree_transaction_stats_read(struct file *file, char __user *buf,
742 					    size_t size, loff_t *ppos)
743 {
744 	struct dump_iter        *i = file->private_data;
745 	struct bch_fs *c = i->c;
746 	int err;
747 
748 	i->ubuf = buf;
749 	i->size = size;
750 	i->ret  = 0;
751 
752 	while (1) {
753 		struct btree_transaction_stats *s = &c->btree_transaction_stats[i->iter];
754 
755 		err = flush_buf(i);
756 		if (err)
757 			return err;
758 
759 		if (!i->size)
760 			break;
761 
762 		if (i->iter == ARRAY_SIZE(bch2_btree_transaction_fns) ||
763 		    !bch2_btree_transaction_fns[i->iter])
764 			break;
765 
766 		prt_printf(&i->buf, "%s:\n", bch2_btree_transaction_fns[i->iter]);
767 		printbuf_indent_add(&i->buf, 2);
768 
769 		mutex_lock(&s->lock);
770 
771 		prt_printf(&i->buf, "Max mem used: %u\n", s->max_mem);
772 		prt_printf(&i->buf, "Transaction duration:\n");
773 
774 		printbuf_indent_add(&i->buf, 2);
775 		bch2_time_stats_to_text(&i->buf, &s->duration);
776 		printbuf_indent_sub(&i->buf, 2);
777 
778 		if (IS_ENABLED(CONFIG_BCACHEFS_LOCK_TIME_STATS)) {
779 			prt_printf(&i->buf, "Lock hold times:\n");
780 
781 			printbuf_indent_add(&i->buf, 2);
782 			bch2_time_stats_to_text(&i->buf, &s->lock_hold_times);
783 			printbuf_indent_sub(&i->buf, 2);
784 		}
785 
786 		if (s->max_paths_text) {
787 			prt_printf(&i->buf, "Maximum allocated btree paths (%u):\n", s->nr_max_paths);
788 
789 			printbuf_indent_add(&i->buf, 2);
790 			prt_str_indented(&i->buf, s->max_paths_text);
791 			printbuf_indent_sub(&i->buf, 2);
792 		}
793 
794 		mutex_unlock(&s->lock);
795 
796 		printbuf_indent_sub(&i->buf, 2);
797 		prt_newline(&i->buf);
798 		i->iter++;
799 	}
800 
801 	if (i->buf.allocation_failure)
802 		return -ENOMEM;
803 
804 	return i->ret;
805 }
806 
807 static const struct file_operations btree_transaction_stats_op = {
808 	.owner		= THIS_MODULE,
809 	.open		= btree_transaction_stats_open,
810 	.release	= btree_transaction_stats_release,
811 	.read		= btree_transaction_stats_read,
812 };
813 
814 /* walk btree transactions until we find a deadlock and print it */
btree_deadlock_to_text(struct printbuf * out,struct bch_fs * c)815 static void btree_deadlock_to_text(struct printbuf *out, struct bch_fs *c)
816 {
817 	struct btree_trans *trans;
818 	ulong iter = 0;
819 restart:
820 	seqmutex_lock(&c->btree_trans_lock);
821 	list_sort(&c->btree_trans_list, list_ptr_order_cmp);
822 
823 	list_for_each_entry(trans, &c->btree_trans_list, list) {
824 		if ((ulong) trans <= iter)
825 			continue;
826 
827 		iter = (ulong) trans;
828 
829 		if (!closure_get_not_zero(&trans->ref))
830 			continue;
831 
832 		u32 seq = seqmutex_unlock(&c->btree_trans_lock);
833 
834 		bool found = bch2_check_for_deadlock(trans, out) != 0;
835 
836 		closure_put(&trans->ref);
837 
838 		if (found)
839 			return;
840 
841 		if (!seqmutex_relock(&c->btree_trans_lock, seq))
842 			goto restart;
843 	}
844 	seqmutex_unlock(&c->btree_trans_lock);
845 }
846 
bch2_btree_deadlock_read(struct file * file,char __user * buf,size_t size,loff_t * ppos)847 static ssize_t bch2_btree_deadlock_read(struct file *file, char __user *buf,
848 					    size_t size, loff_t *ppos)
849 {
850 	struct dump_iter *i = file->private_data;
851 	struct bch_fs *c = i->c;
852 	ssize_t ret = 0;
853 
854 	i->ubuf = buf;
855 	i->size	= size;
856 	i->ret	= 0;
857 
858 	if (!i->iter) {
859 		btree_deadlock_to_text(&i->buf, c);
860 		i->iter++;
861 	}
862 
863 	if (i->buf.allocation_failure)
864 		ret = -ENOMEM;
865 
866 	if (!ret)
867 		ret = flush_buf(i);
868 
869 	return ret ?: i->ret;
870 }
871 
872 static const struct file_operations btree_deadlock_ops = {
873 	.owner		= THIS_MODULE,
874 	.open		= bch2_dump_open,
875 	.release	= bch2_dump_release,
876 	.read		= bch2_btree_deadlock_read,
877 };
878 
bch2_fs_debug_exit(struct bch_fs * c)879 void bch2_fs_debug_exit(struct bch_fs *c)
880 {
881 	if (!IS_ERR_OR_NULL(c->fs_debug_dir))
882 		debugfs_remove_recursive(c->fs_debug_dir);
883 }
884 
bch2_fs_debug_btree_init(struct bch_fs * c,struct btree_debug * bd)885 static void bch2_fs_debug_btree_init(struct bch_fs *c, struct btree_debug *bd)
886 {
887 	struct dentry *d;
888 
889 	d = debugfs_create_dir(bch2_btree_id_str(bd->id), c->btree_debug_dir);
890 
891 	debugfs_create_file("keys", 0400, d, bd, &btree_debug_ops);
892 
893 	debugfs_create_file("formats", 0400, d, bd, &btree_format_debug_ops);
894 
895 	debugfs_create_file("bfloat-failed", 0400, d, bd,
896 			    &bfloat_failed_debug_ops);
897 }
898 
bch2_fs_debug_init(struct bch_fs * c)899 void bch2_fs_debug_init(struct bch_fs *c)
900 {
901 	struct btree_debug *bd;
902 	char name[100];
903 
904 	if (IS_ERR_OR_NULL(bch_debug))
905 		return;
906 
907 	snprintf(name, sizeof(name), "%pU", c->sb.user_uuid.b);
908 	c->fs_debug_dir = debugfs_create_dir(name, bch_debug);
909 	if (IS_ERR_OR_NULL(c->fs_debug_dir))
910 		return;
911 
912 	debugfs_create_file("cached_btree_nodes", 0400, c->fs_debug_dir,
913 			    c->btree_debug, &cached_btree_nodes_ops);
914 
915 	debugfs_create_file("btree_transactions", 0400, c->fs_debug_dir,
916 			    c->btree_debug, &btree_transactions_ops);
917 
918 	debugfs_create_file("journal_pins", 0400, c->fs_debug_dir,
919 			    c->btree_debug, &journal_pins_ops);
920 
921 	debugfs_create_file("btree_updates", 0400, c->fs_debug_dir,
922 			    c->btree_debug, &btree_updates_ops);
923 
924 	debugfs_create_file("btree_transaction_stats", 0400, c->fs_debug_dir,
925 			    c, &btree_transaction_stats_op);
926 
927 	debugfs_create_file("btree_deadlock", 0400, c->fs_debug_dir,
928 			    c->btree_debug, &btree_deadlock_ops);
929 
930 	c->btree_debug_dir = debugfs_create_dir("btrees", c->fs_debug_dir);
931 	if (IS_ERR_OR_NULL(c->btree_debug_dir))
932 		return;
933 
934 	for (bd = c->btree_debug;
935 	     bd < c->btree_debug + ARRAY_SIZE(c->btree_debug);
936 	     bd++) {
937 		bd->id = bd - c->btree_debug;
938 		bch2_fs_debug_btree_init(c, bd);
939 	}
940 }
941 
942 #endif
943 
bch2_debug_exit(void)944 void bch2_debug_exit(void)
945 {
946 	if (!IS_ERR_OR_NULL(bch_debug))
947 		debugfs_remove_recursive(bch_debug);
948 }
949 
bch2_debug_init(void)950 int __init bch2_debug_init(void)
951 {
952 	bch_debug = debugfs_create_dir("bcachefs", NULL);
953 	return 0;
954 }
955