]> git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/debug.c
Update bcachefs sources to 841a95c29f4c bcachefs: fix userspace build errors
[bcachefs-tools-debian] / libbcachefs / debug.c
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 "buckets.h"
17 #include "debug.h"
18 #include "error.h"
19 #include "extents.h"
20 #include "fsck.h"
21 #include "inode.h"
22 #include "super.h"
23
24 #include <linux/console.h>
25 #include <linux/debugfs.h>
26 #include <linux/module.h>
27 #include <linux/random.h>
28 #include <linux/seq_file.h>
29
30 static struct dentry *bch_debug;
31
32 static bool bch2_btree_verify_replica(struct bch_fs *c, struct btree *b,
33                                       struct extent_ptr_decoded pick)
34 {
35         struct btree *v = c->verify_data;
36         struct btree_node *n_ondisk = c->verify_ondisk;
37         struct btree_node *n_sorted = c->verify_data->data;
38         struct bset *sorted, *inmemory = &b->data->keys;
39         struct bch_dev *ca = bch_dev_bkey_exists(c, pick.ptr.dev);
40         struct bio *bio;
41         bool failed = false, saw_error = false;
42
43         if (!bch2_dev_get_ioref(ca, READ))
44                 return false;
45
46         bio = bio_alloc_bioset(ca->disk_sb.bdev,
47                                buf_pages(n_sorted, btree_bytes(c)),
48                                REQ_OP_READ|REQ_META,
49                                GFP_NOFS,
50                                &c->btree_bio);
51         bio->bi_iter.bi_sector  = pick.ptr.offset;
52         bch2_bio_map(bio, n_sorted, btree_bytes(c));
53
54         submit_bio_wait(bio);
55
56         bio_put(bio);
57         percpu_ref_put(&ca->io_ref);
58
59         memcpy(n_ondisk, n_sorted, btree_bytes(c));
60
61         v->written = 0;
62         if (bch2_btree_node_read_done(c, ca, v, false, &saw_error) || saw_error)
63                 return false;
64
65         n_sorted = c->verify_data->data;
66         sorted = &n_sorted->keys;
67
68         if (inmemory->u64s != sorted->u64s ||
69             memcmp(inmemory->start,
70                    sorted->start,
71                    vstruct_end(inmemory) - (void *) inmemory->start)) {
72                 unsigned offset = 0, sectors;
73                 struct bset *i;
74                 unsigned j;
75
76                 console_lock();
77
78                 printk(KERN_ERR "*** in memory:\n");
79                 bch2_dump_bset(c, b, inmemory, 0);
80
81                 printk(KERN_ERR "*** read back in:\n");
82                 bch2_dump_bset(c, v, sorted, 0);
83
84                 while (offset < v->written) {
85                         if (!offset) {
86                                 i = &n_ondisk->keys;
87                                 sectors = vstruct_blocks(n_ondisk, c->block_bits) <<
88                                         c->block_bits;
89                         } else {
90                                 struct btree_node_entry *bne =
91                                         (void *) n_ondisk + (offset << 9);
92                                 i = &bne->keys;
93
94                                 sectors = vstruct_blocks(bne, c->block_bits) <<
95                                         c->block_bits;
96                         }
97
98                         printk(KERN_ERR "*** on disk block %u:\n", offset);
99                         bch2_dump_bset(c, b, i, offset);
100
101                         offset += sectors;
102                 }
103
104                 for (j = 0; j < le16_to_cpu(inmemory->u64s); j++)
105                         if (inmemory->_data[j] != sorted->_data[j])
106                                 break;
107
108                 console_unlock();
109                 bch_err(c, "verify failed at key %u", j);
110
111                 failed = true;
112         }
113
114         if (v->written != b->written) {
115                 bch_err(c, "written wrong: expected %u, got %u",
116                         b->written, v->written);
117                 failed = true;
118         }
119
120         return failed;
121 }
122
123 void __bch2_btree_verify(struct bch_fs *c, struct btree *b)
124 {
125         struct bkey_ptrs_c ptrs;
126         struct extent_ptr_decoded p;
127         const union bch_extent_entry *entry;
128         struct btree *v;
129         struct bset *inmemory = &b->data->keys;
130         struct bkey_packed *k;
131         bool failed = false;
132
133         if (c->opts.nochanges)
134                 return;
135
136         bch2_btree_node_io_lock(b);
137         mutex_lock(&c->verify_lock);
138
139         if (!c->verify_ondisk) {
140                 c->verify_ondisk = kvpmalloc(btree_bytes(c), GFP_KERNEL);
141                 if (!c->verify_ondisk)
142                         goto out;
143         }
144
145         if (!c->verify_data) {
146                 c->verify_data = __bch2_btree_node_mem_alloc(c);
147                 if (!c->verify_data)
148                         goto out;
149
150                 list_del_init(&c->verify_data->list);
151         }
152
153         BUG_ON(b->nsets != 1);
154
155         for (k = inmemory->start; k != vstruct_last(inmemory); k = bkey_p_next(k))
156                 if (k->type == KEY_TYPE_btree_ptr_v2)
157                         ((struct bch_btree_ptr_v2 *) bkeyp_val(&b->format, k))->mem_ptr = 0;
158
159         v = c->verify_data;
160         bkey_copy(&v->key, &b->key);
161         v->c.level      = b->c.level;
162         v->c.btree_id   = b->c.btree_id;
163         bch2_btree_keys_init(v);
164
165         ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(&b->key));
166         bkey_for_each_ptr_decode(&b->key.k, ptrs, p, entry)
167                 failed |= bch2_btree_verify_replica(c, b, p);
168
169         if (failed) {
170                 struct printbuf buf = PRINTBUF;
171
172                 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
173                 bch2_fs_fatal_error(c, "btree node verify failed for : %s\n", buf.buf);
174                 printbuf_exit(&buf);
175         }
176 out:
177         mutex_unlock(&c->verify_lock);
178         bch2_btree_node_io_unlock(b);
179 }
180
181 void bch2_btree_node_ondisk_to_text(struct printbuf *out, struct bch_fs *c,
182                                     const struct btree *b)
183 {
184         struct btree_node *n_ondisk = NULL;
185         struct extent_ptr_decoded pick;
186         struct bch_dev *ca;
187         struct bio *bio = NULL;
188         unsigned offset = 0;
189         int ret;
190
191         if (bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key), NULL, &pick) <= 0) {
192                 prt_printf(out, "error getting device to read from: invalid device\n");
193                 return;
194         }
195
196         ca = bch_dev_bkey_exists(c, pick.ptr.dev);
197         if (!bch2_dev_get_ioref(ca, READ)) {
198                 prt_printf(out, "error getting device to read from: not online\n");
199                 return;
200         }
201
202         n_ondisk = kvpmalloc(btree_bytes(c), GFP_KERNEL);
203         if (!n_ondisk) {
204                 prt_printf(out, "memory allocation failure\n");
205                 goto out;
206         }
207
208         bio = bio_alloc_bioset(ca->disk_sb.bdev,
209                                buf_pages(n_ondisk, btree_bytes(c)),
210                                REQ_OP_READ|REQ_META,
211                                GFP_NOFS,
212                                &c->btree_bio);
213         bio->bi_iter.bi_sector  = pick.ptr.offset;
214         bch2_bio_map(bio, n_ondisk, btree_bytes(c));
215
216         ret = submit_bio_wait(bio);
217         if (ret) {
218                 prt_printf(out, "IO error reading btree node: %s\n", bch2_err_str(ret));
219                 goto out;
220         }
221
222         while (offset < btree_sectors(c)) {
223                 struct bset *i;
224                 struct nonce nonce;
225                 struct bch_csum csum;
226                 struct bkey_packed *k;
227                 unsigned sectors;
228
229                 if (!offset) {
230                         i = &n_ondisk->keys;
231
232                         if (!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i))) {
233                                 prt_printf(out, "unknown checksum type at offset %u: %llu\n",
234                                            offset, BSET_CSUM_TYPE(i));
235                                 goto out;
236                         }
237
238                         nonce = btree_nonce(i, offset << 9);
239                         csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, n_ondisk);
240
241                         if (bch2_crc_cmp(csum, n_ondisk->csum)) {
242                                 prt_printf(out, "invalid checksum\n");
243                                 goto out;
244                         }
245
246                         bset_encrypt(c, i, offset << 9);
247
248                         sectors = vstruct_sectors(n_ondisk, c->block_bits);
249                 } else {
250                         struct btree_node_entry *bne = (void *) n_ondisk + (offset << 9);
251
252                         i = &bne->keys;
253
254                         if (i->seq != n_ondisk->keys.seq)
255                                 break;
256
257                         if (!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i))) {
258                                 prt_printf(out, "unknown checksum type at offset %u: %llu\n",
259                                            offset, BSET_CSUM_TYPE(i));
260                                 goto out;
261                         }
262
263                         nonce = btree_nonce(i, offset << 9);
264                         csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bne);
265
266                         if (bch2_crc_cmp(csum, bne->csum)) {
267                                 prt_printf(out, "invalid checksum");
268                                 goto out;
269                         }
270
271                         bset_encrypt(c, i, offset << 9);
272
273                         sectors = vstruct_sectors(bne, c->block_bits);
274                 }
275
276                 prt_printf(out, "  offset %u version %u, journal seq %llu\n",
277                            offset,
278                            le16_to_cpu(i->version),
279                            le64_to_cpu(i->journal_seq));
280                 offset += sectors;
281
282                 printbuf_indent_add(out, 4);
283
284                 for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k)) {
285                         struct bkey u;
286
287                         bch2_bkey_val_to_text(out, c, bkey_disassemble(b, k, &u));
288                         prt_newline(out);
289                 }
290
291                 printbuf_indent_sub(out, 4);
292         }
293 out:
294         if (bio)
295                 bio_put(bio);
296         kvpfree(n_ondisk, btree_bytes(c));
297         percpu_ref_put(&ca->io_ref);
298 }
299
300 #ifdef CONFIG_DEBUG_FS
301
302 /* XXX: bch_fs refcounting */
303
304 struct dump_iter {
305         struct bch_fs           *c;
306         enum btree_id           id;
307         struct bpos             from;
308         struct bpos             prev_node;
309         u64                     iter;
310
311         struct printbuf         buf;
312
313         char __user             *ubuf;  /* destination user buffer */
314         size_t                  size;   /* size of requested read */
315         ssize_t                 ret;    /* bytes read so far */
316 };
317
318 static ssize_t flush_buf(struct dump_iter *i)
319 {
320         if (i->buf.pos) {
321                 size_t bytes = min_t(size_t, i->buf.pos, i->size);
322                 int copied = bytes - copy_to_user(i->ubuf, i->buf.buf, bytes);
323
324                 i->ret   += copied;
325                 i->ubuf  += copied;
326                 i->size  -= copied;
327                 i->buf.pos -= copied;
328                 memmove(i->buf.buf, i->buf.buf + copied, i->buf.pos);
329
330                 if (copied != bytes)
331                         return -EFAULT;
332         }
333
334         return i->size ? 0 : i->ret;
335 }
336
337 static int bch2_dump_open(struct inode *inode, struct file *file)
338 {
339         struct btree_debug *bd = inode->i_private;
340         struct dump_iter *i;
341
342         i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
343         if (!i)
344                 return -ENOMEM;
345
346         file->private_data = i;
347         i->from = POS_MIN;
348         i->iter = 0;
349         i->c    = container_of(bd, struct bch_fs, btree_debug[bd->id]);
350         i->id   = bd->id;
351         i->buf  = PRINTBUF;
352
353         return 0;
354 }
355
356 static int bch2_dump_release(struct inode *inode, struct file *file)
357 {
358         struct dump_iter *i = file->private_data;
359
360         printbuf_exit(&i->buf);
361         kfree(i);
362         return 0;
363 }
364
365 static ssize_t bch2_read_btree(struct file *file, char __user *buf,
366                                size_t size, loff_t *ppos)
367 {
368         struct dump_iter *i = file->private_data;
369         struct btree_trans *trans;
370         struct btree_iter iter;
371         struct bkey_s_c k;
372         ssize_t ret;
373
374         i->ubuf = buf;
375         i->size = size;
376         i->ret  = 0;
377
378         ret = flush_buf(i);
379         if (ret)
380                 return ret;
381
382         trans = bch2_trans_get(i->c);
383         ret = for_each_btree_key(trans, iter, i->id, i->from,
384                                  BTREE_ITER_PREFETCH|
385                                  BTREE_ITER_ALL_SNAPSHOTS, k, ({
386                 bch2_bkey_val_to_text(&i->buf, i->c, k);
387                 prt_newline(&i->buf);
388                 bch2_trans_unlock(trans);
389                 flush_buf(i);
390         }));
391         i->from = iter.pos;
392
393         bch2_trans_put(trans);
394
395         if (!ret)
396                 ret = flush_buf(i);
397
398         return ret ?: i->ret;
399 }
400
401 static const struct file_operations btree_debug_ops = {
402         .owner          = THIS_MODULE,
403         .open           = bch2_dump_open,
404         .release        = bch2_dump_release,
405         .read           = bch2_read_btree,
406 };
407
408 static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
409                                        size_t size, loff_t *ppos)
410 {
411         struct dump_iter *i = file->private_data;
412         struct btree_trans *trans;
413         struct btree_iter iter;
414         struct btree *b;
415         ssize_t ret;
416
417         i->ubuf = buf;
418         i->size = size;
419         i->ret  = 0;
420
421         ret = flush_buf(i);
422         if (ret)
423                 return ret;
424
425         if (bpos_eq(SPOS_MAX, i->from))
426                 return i->ret;
427
428         trans = bch2_trans_get(i->c);
429 retry:
430         bch2_trans_begin(trans);
431
432         for_each_btree_node(trans, iter, i->id, i->from, 0, b, ret) {
433                 bch2_btree_node_to_text(&i->buf, i->c, b);
434                 i->from = !bpos_eq(SPOS_MAX, b->key.k.p)
435                         ? bpos_successor(b->key.k.p)
436                         : b->key.k.p;
437
438                 ret = drop_locks_do(trans, flush_buf(i));
439                 if (ret)
440                         break;
441         }
442         bch2_trans_iter_exit(trans, &iter);
443
444         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
445                 goto retry;
446
447         bch2_trans_put(trans);
448
449         if (!ret)
450                 ret = flush_buf(i);
451
452         return ret ?: i->ret;
453 }
454
455 static const struct file_operations btree_format_debug_ops = {
456         .owner          = THIS_MODULE,
457         .open           = bch2_dump_open,
458         .release        = bch2_dump_release,
459         .read           = bch2_read_btree_formats,
460 };
461
462 static ssize_t bch2_read_bfloat_failed(struct file *file, char __user *buf,
463                                        size_t size, loff_t *ppos)
464 {
465         struct dump_iter *i = file->private_data;
466         struct btree_trans *trans;
467         struct btree_iter iter;
468         struct bkey_s_c k;
469         ssize_t ret;
470
471         i->ubuf = buf;
472         i->size = size;
473         i->ret  = 0;
474
475         ret = flush_buf(i);
476         if (ret)
477                 return ret;
478
479         trans = bch2_trans_get(i->c);
480
481         ret = for_each_btree_key(trans, iter, i->id, i->from,
482                                  BTREE_ITER_PREFETCH|
483                                  BTREE_ITER_ALL_SNAPSHOTS, k, ({
484                 struct btree_path_level *l =
485                         &btree_iter_path(trans, &iter)->l[0];
486                 struct bkey_packed *_k =
487                         bch2_btree_node_iter_peek(&l->iter, l->b);
488
489                 if (bpos_gt(l->b->key.k.p, i->prev_node)) {
490                         bch2_btree_node_to_text(&i->buf, i->c, l->b);
491                         i->prev_node = l->b->key.k.p;
492                 }
493
494                 bch2_bfloat_to_text(&i->buf, l->b, _k);
495                 bch2_trans_unlock(trans);
496                 flush_buf(i);
497         }));
498         i->from = iter.pos;
499
500         bch2_trans_put(trans);
501
502         if (!ret)
503                 ret = flush_buf(i);
504
505         return ret ?: i->ret;
506 }
507
508 static const struct file_operations bfloat_failed_debug_ops = {
509         .owner          = THIS_MODULE,
510         .open           = bch2_dump_open,
511         .release        = bch2_dump_release,
512         .read           = bch2_read_bfloat_failed,
513 };
514
515 static void bch2_cached_btree_node_to_text(struct printbuf *out, struct bch_fs *c,
516                                            struct btree *b)
517 {
518         if (!out->nr_tabstops)
519                 printbuf_tabstop_push(out, 32);
520
521         prt_printf(out, "%px btree=%s l=%u ",
522                b,
523                bch2_btree_id_str(b->c.btree_id),
524                b->c.level);
525         prt_newline(out);
526
527         printbuf_indent_add(out, 2);
528
529         bch2_bkey_val_to_text(out, c, bkey_i_to_s_c(&b->key));
530         prt_newline(out);
531
532         prt_printf(out, "flags: ");
533         prt_tab(out);
534         prt_bitflags(out, bch2_btree_node_flags, b->flags);
535         prt_newline(out);
536
537         prt_printf(out, "pcpu read locks: ");
538         prt_tab(out);
539         prt_printf(out, "%u", b->c.lock.readers != NULL);
540         prt_newline(out);
541
542         prt_printf(out, "written:");
543         prt_tab(out);
544         prt_printf(out, "%u", b->written);
545         prt_newline(out);
546
547         prt_printf(out, "writes blocked:");
548         prt_tab(out);
549         prt_printf(out, "%u", !list_empty_careful(&b->write_blocked));
550         prt_newline(out);
551
552         prt_printf(out, "will make reachable:");
553         prt_tab(out);
554         prt_printf(out, "%lx", b->will_make_reachable);
555         prt_newline(out);
556
557         prt_printf(out, "journal pin %px:", &b->writes[0].journal);
558         prt_tab(out);
559         prt_printf(out, "%llu", b->writes[0].journal.seq);
560         prt_newline(out);
561
562         prt_printf(out, "journal pin %px:", &b->writes[1].journal);
563         prt_tab(out);
564         prt_printf(out, "%llu", b->writes[1].journal.seq);
565         prt_newline(out);
566
567         printbuf_indent_sub(out, 2);
568 }
569
570 static ssize_t bch2_cached_btree_nodes_read(struct file *file, char __user *buf,
571                                             size_t size, loff_t *ppos)
572 {
573         struct dump_iter *i = file->private_data;
574         struct bch_fs *c = i->c;
575         bool done = false;
576         ssize_t ret = 0;
577
578         i->ubuf = buf;
579         i->size = size;
580         i->ret  = 0;
581
582         do {
583                 struct bucket_table *tbl;
584                 struct rhash_head *pos;
585                 struct btree *b;
586
587                 ret = flush_buf(i);
588                 if (ret)
589                         return ret;
590
591                 rcu_read_lock();
592                 i->buf.atomic++;
593                 tbl = rht_dereference_rcu(c->btree_cache.table.tbl,
594                                           &c->btree_cache.table);
595                 if (i->iter < tbl->size) {
596                         rht_for_each_entry_rcu(b, pos, tbl, i->iter, hash)
597                                 bch2_cached_btree_node_to_text(&i->buf, c, b);
598                         i->iter++;
599                 } else {
600                         done = true;
601                 }
602                 --i->buf.atomic;
603                 rcu_read_unlock();
604         } while (!done);
605
606         if (i->buf.allocation_failure)
607                 ret = -ENOMEM;
608
609         if (!ret)
610                 ret = flush_buf(i);
611
612         return ret ?: i->ret;
613 }
614
615 static const struct file_operations cached_btree_nodes_ops = {
616         .owner          = THIS_MODULE,
617         .open           = bch2_dump_open,
618         .release        = bch2_dump_release,
619         .read           = bch2_cached_btree_nodes_read,
620 };
621
622 static ssize_t bch2_btree_transactions_read(struct file *file, char __user *buf,
623                                             size_t size, loff_t *ppos)
624 {
625         struct dump_iter *i = file->private_data;
626         struct bch_fs *c = i->c;
627         struct btree_trans *trans;
628         ssize_t ret = 0;
629         u32 seq;
630
631         i->ubuf = buf;
632         i->size = size;
633         i->ret  = 0;
634 restart:
635         seqmutex_lock(&c->btree_trans_lock);
636         list_for_each_entry(trans, &c->btree_trans_list, list) {
637                 struct task_struct *task = READ_ONCE(trans->locking_wait.task);
638
639                 if (!task || task->pid <= i->iter)
640                         continue;
641
642                 closure_get(&trans->ref);
643                 seq = seqmutex_seq(&c->btree_trans_lock);
644                 seqmutex_unlock(&c->btree_trans_lock);
645
646                 ret = flush_buf(i);
647                 if (ret) {
648                         closure_put(&trans->ref);
649                         goto unlocked;
650                 }
651
652                 bch2_btree_trans_to_text(&i->buf, trans);
653
654                 prt_printf(&i->buf, "backtrace:");
655                 prt_newline(&i->buf);
656                 printbuf_indent_add(&i->buf, 2);
657                 bch2_prt_task_backtrace(&i->buf, task);
658                 printbuf_indent_sub(&i->buf, 2);
659                 prt_newline(&i->buf);
660
661                 i->iter = task->pid;
662
663                 closure_put(&trans->ref);
664
665                 if (!seqmutex_relock(&c->btree_trans_lock, seq))
666                         goto restart;
667         }
668         seqmutex_unlock(&c->btree_trans_lock);
669 unlocked:
670         if (i->buf.allocation_failure)
671                 ret = -ENOMEM;
672
673         if (!ret)
674                 ret = flush_buf(i);
675
676         return ret ?: i->ret;
677 }
678
679 static const struct file_operations btree_transactions_ops = {
680         .owner          = THIS_MODULE,
681         .open           = bch2_dump_open,
682         .release        = bch2_dump_release,
683         .read           = bch2_btree_transactions_read,
684 };
685
686 static ssize_t bch2_journal_pins_read(struct file *file, char __user *buf,
687                                       size_t size, loff_t *ppos)
688 {
689         struct dump_iter *i = file->private_data;
690         struct bch_fs *c = i->c;
691         bool done = false;
692         int err;
693
694         i->ubuf = buf;
695         i->size = size;
696         i->ret  = 0;
697
698         do {
699                 err = flush_buf(i);
700                 if (err)
701                         return err;
702
703                 if (!i->size)
704                         break;
705
706                 done = bch2_journal_seq_pins_to_text(&i->buf, &c->journal, &i->iter);
707                 i->iter++;
708         } while (!done);
709
710         if (i->buf.allocation_failure)
711                 return -ENOMEM;
712
713         return i->ret;
714 }
715
716 static const struct file_operations journal_pins_ops = {
717         .owner          = THIS_MODULE,
718         .open           = bch2_dump_open,
719         .release        = bch2_dump_release,
720         .read           = bch2_journal_pins_read,
721 };
722
723 static int lock_held_stats_open(struct inode *inode, struct file *file)
724 {
725         struct bch_fs *c = inode->i_private;
726         struct dump_iter *i;
727
728         i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
729
730         if (!i)
731                 return -ENOMEM;
732
733         i->iter = 0;
734         i->c    = c;
735         i->buf  = PRINTBUF;
736         file->private_data = i;
737
738         return 0;
739 }
740
741 static int lock_held_stats_release(struct inode *inode, struct file *file)
742 {
743         struct dump_iter *i = file->private_data;
744
745         printbuf_exit(&i->buf);
746         kfree(i);
747
748         return 0;
749 }
750
751 static ssize_t lock_held_stats_read(struct file *file, char __user *buf,
752                                       size_t size, loff_t *ppos)
753 {
754         struct dump_iter        *i = file->private_data;
755         struct bch_fs *c = i->c;
756         int err;
757
758         i->ubuf = buf;
759         i->size = size;
760         i->ret  = 0;
761
762         while (1) {
763                 struct btree_transaction_stats *s = &c->btree_transaction_stats[i->iter];
764
765                 err = flush_buf(i);
766                 if (err)
767                         return err;
768
769                 if (!i->size)
770                         break;
771
772                 if (i->iter == ARRAY_SIZE(bch2_btree_transaction_fns) ||
773                     !bch2_btree_transaction_fns[i->iter])
774                         break;
775
776                 prt_printf(&i->buf, "%s: ", bch2_btree_transaction_fns[i->iter]);
777                 prt_newline(&i->buf);
778                 printbuf_indent_add(&i->buf, 2);
779
780                 mutex_lock(&s->lock);
781
782                 prt_printf(&i->buf, "Max mem used: %u", s->max_mem);
783                 prt_newline(&i->buf);
784
785                 if (IS_ENABLED(CONFIG_BCACHEFS_LOCK_TIME_STATS)) {
786                         prt_printf(&i->buf, "Lock hold times:");
787                         prt_newline(&i->buf);
788
789                         printbuf_indent_add(&i->buf, 2);
790                         bch2_time_stats_to_text(&i->buf, &s->lock_hold_times);
791                         printbuf_indent_sub(&i->buf, 2);
792                 }
793
794                 if (s->max_paths_text) {
795                         prt_printf(&i->buf, "Maximum allocated btree paths (%u):", s->nr_max_paths);
796                         prt_newline(&i->buf);
797
798                         printbuf_indent_add(&i->buf, 2);
799                         prt_str_indented(&i->buf, s->max_paths_text);
800                         printbuf_indent_sub(&i->buf, 2);
801                 }
802
803                 mutex_unlock(&s->lock);
804
805                 printbuf_indent_sub(&i->buf, 2);
806                 prt_newline(&i->buf);
807                 i->iter++;
808         }
809
810         if (i->buf.allocation_failure)
811                 return -ENOMEM;
812
813         return i->ret;
814 }
815
816 static const struct file_operations lock_held_stats_op = {
817         .owner = THIS_MODULE,
818         .open = lock_held_stats_open,
819         .release = lock_held_stats_release,
820         .read = lock_held_stats_read,
821 };
822
823 static ssize_t bch2_btree_deadlock_read(struct file *file, char __user *buf,
824                                             size_t size, loff_t *ppos)
825 {
826         struct dump_iter *i = file->private_data;
827         struct bch_fs *c = i->c;
828         struct btree_trans *trans;
829         ssize_t ret = 0;
830         u32 seq;
831
832         i->ubuf = buf;
833         i->size = size;
834         i->ret  = 0;
835
836         if (i->iter)
837                 goto out;
838 restart:
839         seqmutex_lock(&c->btree_trans_lock);
840         list_for_each_entry(trans, &c->btree_trans_list, list) {
841                 struct task_struct *task = READ_ONCE(trans->locking_wait.task);
842
843                 if (!task || task->pid <= i->iter)
844                         continue;
845
846                 closure_get(&trans->ref);
847                 seq = seqmutex_seq(&c->btree_trans_lock);
848                 seqmutex_unlock(&c->btree_trans_lock);
849
850                 ret = flush_buf(i);
851                 if (ret) {
852                         closure_put(&trans->ref);
853                         goto out;
854                 }
855
856                 bch2_check_for_deadlock(trans, &i->buf);
857
858                 i->iter = task->pid;
859
860                 closure_put(&trans->ref);
861
862                 if (!seqmutex_relock(&c->btree_trans_lock, seq))
863                         goto restart;
864         }
865         seqmutex_unlock(&c->btree_trans_lock);
866 out:
867         if (i->buf.allocation_failure)
868                 ret = -ENOMEM;
869
870         if (!ret)
871                 ret = flush_buf(i);
872
873         return ret ?: i->ret;
874 }
875
876 static const struct file_operations btree_deadlock_ops = {
877         .owner          = THIS_MODULE,
878         .open           = bch2_dump_open,
879         .release        = bch2_dump_release,
880         .read           = bch2_btree_deadlock_read,
881 };
882
883 void bch2_fs_debug_exit(struct bch_fs *c)
884 {
885         if (!IS_ERR_OR_NULL(c->fs_debug_dir))
886                 debugfs_remove_recursive(c->fs_debug_dir);
887 }
888
889 void bch2_fs_debug_init(struct bch_fs *c)
890 {
891         struct btree_debug *bd;
892         char name[100];
893
894         if (IS_ERR_OR_NULL(bch_debug))
895                 return;
896
897         snprintf(name, sizeof(name), "%pU", c->sb.user_uuid.b);
898         c->fs_debug_dir = debugfs_create_dir(name, bch_debug);
899         if (IS_ERR_OR_NULL(c->fs_debug_dir))
900                 return;
901
902         debugfs_create_file("cached_btree_nodes", 0400, c->fs_debug_dir,
903                             c->btree_debug, &cached_btree_nodes_ops);
904
905         debugfs_create_file("btree_transactions", 0400, c->fs_debug_dir,
906                             c->btree_debug, &btree_transactions_ops);
907
908         debugfs_create_file("journal_pins", 0400, c->fs_debug_dir,
909                             c->btree_debug, &journal_pins_ops);
910
911         debugfs_create_file("btree_transaction_stats", 0400, c->fs_debug_dir,
912                             c, &lock_held_stats_op);
913
914         debugfs_create_file("btree_deadlock", 0400, c->fs_debug_dir,
915                             c->btree_debug, &btree_deadlock_ops);
916
917         c->btree_debug_dir = debugfs_create_dir("btrees", c->fs_debug_dir);
918         if (IS_ERR_OR_NULL(c->btree_debug_dir))
919                 return;
920
921         for (bd = c->btree_debug;
922              bd < c->btree_debug + ARRAY_SIZE(c->btree_debug);
923              bd++) {
924                 bd->id = bd - c->btree_debug;
925                 debugfs_create_file(bch2_btree_id_str(bd->id),
926                                     0400, c->btree_debug_dir, bd,
927                                     &btree_debug_ops);
928
929                 snprintf(name, sizeof(name), "%s-formats",
930                          bch2_btree_id_str(bd->id));
931
932                 debugfs_create_file(name, 0400, c->btree_debug_dir, bd,
933                                     &btree_format_debug_ops);
934
935                 snprintf(name, sizeof(name), "%s-bfloat-failed",
936                          bch2_btree_id_str(bd->id));
937
938                 debugfs_create_file(name, 0400, c->btree_debug_dir, bd,
939                                     &bfloat_failed_debug_ops);
940         }
941 }
942
943 #endif
944
945 void bch2_debug_exit(void)
946 {
947         if (!IS_ERR_OR_NULL(bch_debug))
948                 debugfs_remove_recursive(bch_debug);
949 }
950
951 int __init bch2_debug_init(void)
952 {
953         int ret = 0;
954
955         bch_debug = debugfs_create_dir("bcachefs", NULL);
956         return ret;
957 }