git.sesse.net Git - bcachefs-tools-debian/blob - 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_update.h"
  15 #include "buckets.h"
  16 #include "debug.h"
  17 #include "error.h"
  18 #include "extents.h"
  19 #include "fsck.h"
  20 #include "inode.h"
  21 #include "io.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;
  42
  43         if (!bch2_dev_get_ioref(ca, READ))
  44                 return false;
  45
  46         bio = bio_alloc_bioset(GFP_NOIO,
  47                         buf_pages(n_sorted, btree_bytes(c)),
  48                         &c->btree_bio);
  49         bio_set_dev(bio, ca->disk_sb.bdev);
  50         bio->bi_opf             = REQ_OP_READ|REQ_META;
  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))
  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_next(k))
 156                 if (k->type == KEY_TYPE_btree_ptr_v2) {
 157                         struct bch_btree_ptr_v2 *v = (void *) bkeyp_val(&b->format, k);
 158                         v->mem_ptr = 0;
 159                 }
 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
 183 #ifdef CONFIG_DEBUG_FS
 184
 185 /* XXX: bch_fs refcounting */
 186
 187 struct dump_iter {
 188         struct bpos             from;
 189         struct bch_fs   *c;
 190         enum btree_id           id;
 191
 192         struct printbuf         buf;
 193
 194         char __user             *ubuf;  /* destination user buffer */
 195         size_t                  size;   /* size of requested read */
 196         ssize_t                 ret;    /* bytes read so far */
 197 };
 198
 199 static int flush_buf(struct dump_iter *i)
 200 {
 201         if (i->buf.pos) {
 202                 size_t bytes = min_t(size_t, i->buf.pos, i->size);
 203                 int err = copy_to_user(i->ubuf, i->buf.buf, bytes);
 204
 205                 if (err)
 206                         return err;
 207
 208                 i->ret   += bytes;
 209                 i->ubuf  += bytes;
 210                 i->size  -= bytes;
 211                 i->buf.pos -= bytes;
 212                 memmove(i->buf.buf, i->buf.buf + bytes, i->buf.pos);
 213         }
 214
 215         return 0;
 216 }
 217
 218 static int bch2_dump_open(struct inode *inode, struct file *file)
 219 {
 220         struct btree_debug *bd = inode->i_private;
 221         struct dump_iter *i;
 222
 223         i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
 224         if (!i)
 225                 return -ENOMEM;
 226
 227         file->private_data = i;
 228         i->from = POS_MIN;
 229         i->c    = container_of(bd, struct bch_fs, btree_debug[bd->id]);
 230         i->id   = bd->id;
 231         i->buf  = PRINTBUF;
 232
 233         return 0;
 234 }
 235
 236 static int bch2_dump_release(struct inode *inode, struct file *file)
 237 {
 238         struct dump_iter *i = file->private_data;
 239
 240         printbuf_exit(&i->buf);
 241         kfree(i);
 242         return 0;
 243 }
 244
 245 static ssize_t bch2_read_btree(struct file *file, char __user *buf,
 246                                size_t size, loff_t *ppos)
 247 {
 248         struct dump_iter *i = file->private_data;
 249         struct btree_trans trans;
 250         struct btree_iter iter;
 251         struct bkey_s_c k;
 252         int err;
 253
 254         i->ubuf = buf;
 255         i->size = size;
 256         i->ret  = 0;
 257
 258         err = flush_buf(i);
 259         if (err)
 260                 return err;
 261
 262         if (!i->size)
 263                 return i->ret;
 264
 265         bch2_trans_init(&trans, i->c, 0, 0);
 266
 267         bch2_trans_iter_init(&trans, &iter, i->id, i->from,
 268                              BTREE_ITER_PREFETCH|
 269                              BTREE_ITER_ALL_SNAPSHOTS);
 270         k = bch2_btree_iter_peek(&iter);
 271
 272         while (k.k && !(err = bkey_err(k))) {
 273                 bch2_bkey_val_to_text(&i->buf, i->c, k);
 274                 pr_char(&i->buf, '\n');
 275
 276                 k = bch2_btree_iter_next(&iter);
 277                 i->from = iter.pos;
 278
 279                 err = flush_buf(i);
 280                 if (err)
 281                         break;
 282
 283                 if (!i->size)
 284                         break;
 285         }
 286         bch2_trans_iter_exit(&trans, &iter);
 287
 288         bch2_trans_exit(&trans);
 289
 290         return err < 0 ? err : i->ret;
 291 }
 292
 293 static const struct file_operations btree_debug_ops = {
 294         .owner          = THIS_MODULE,
 295         .open           = bch2_dump_open,
 296         .release        = bch2_dump_release,
 297         .read           = bch2_read_btree,
 298 };
 299
 300 static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
 301                                        size_t size, loff_t *ppos)
 302 {
 303         struct dump_iter *i = file->private_data;
 304         struct btree_trans trans;
 305         struct btree_iter iter;
 306         struct btree *b;
 307         int err;
 308
 309         i->ubuf = buf;
 310         i->size = size;
 311         i->ret  = 0;
 312
 313         err = flush_buf(i);
 314         if (err)
 315                 return err;
 316
 317         if (!i->size || !bpos_cmp(SPOS_MAX, i->from))
 318                 return i->ret;
 319
 320         bch2_trans_init(&trans, i->c, 0, 0);
 321
 322         for_each_btree_node(&trans, iter, i->id, i->from, 0, b, err) {
 323                 bch2_btree_node_to_text(&i->buf, i->c, b);
 324                 err = flush_buf(i);
 325                 if (err)
 326                         break;
 327
 328                 /*
 329                  * can't easily correctly restart a btree node traversal across
 330                  * all nodes, meh
 331                  */
 332                 i->from = bpos_cmp(SPOS_MAX, b->key.k.p)
 333                         ? bpos_successor(b->key.k.p)
 334                         : b->key.k.p;
 335
 336                 if (!i->size)
 337                         break;
 338         }
 339         bch2_trans_iter_exit(&trans, &iter);
 340
 341         bch2_trans_exit(&trans);
 342
 343         return err < 0 ? err : i->ret;
 344 }
 345
 346 static const struct file_operations btree_format_debug_ops = {
 347         .owner          = THIS_MODULE,
 348         .open           = bch2_dump_open,
 349         .release        = bch2_dump_release,
 350         .read           = bch2_read_btree_formats,
 351 };
 352
 353 static ssize_t bch2_read_bfloat_failed(struct file *file, char __user *buf,
 354                                        size_t size, loff_t *ppos)
 355 {
 356         struct dump_iter *i = file->private_data;
 357         struct btree_trans trans;
 358         struct btree_iter iter;
 359         struct bkey_s_c k;
 360         struct btree *prev_node = NULL;
 361         int err;
 362
 363         i->ubuf = buf;
 364         i->size = size;
 365         i->ret  = 0;
 366
 367         err = flush_buf(i);
 368         if (err)
 369                 return err;
 370
 371         if (!i->size)
 372                 return i->ret;
 373
 374         bch2_trans_init(&trans, i->c, 0, 0);
 375
 376         bch2_trans_iter_init(&trans, &iter, i->id, i->from,
 377                              BTREE_ITER_PREFETCH|
 378                              BTREE_ITER_ALL_SNAPSHOTS);
 379
 380         while ((k = bch2_btree_iter_peek(&iter)).k &&
 381                !(err = bkey_err(k))) {
 382                 struct btree_path_level *l = &iter.path->l[0];
 383                 struct bkey_packed *_k =
 384                         bch2_btree_node_iter_peek(&l->iter, l->b);
 385
 386                 if (l->b != prev_node) {
 387                         bch2_btree_node_to_text(&i->buf, i->c, l->b);
 388                         err = flush_buf(i);
 389                         if (err)
 390                                 break;
 391                 }
 392                 prev_node = l->b;
 393
 394                 bch2_bfloat_to_text(&i->buf, l->b, _k);
 395                 err = flush_buf(i);
 396                 if (err)
 397                         break;
 398
 399                 bch2_btree_iter_advance(&iter);
 400                 i->from = iter.pos;
 401
 402                 err = flush_buf(i);
 403                 if (err)
 404                         break;
 405
 406                 if (!i->size)
 407                         break;
 408         }
 409         bch2_trans_iter_exit(&trans, &iter);
 410
 411         bch2_trans_exit(&trans);
 412
 413         return err < 0 ? err : i->ret;
 414 }
 415
 416 static const struct file_operations bfloat_failed_debug_ops = {
 417         .owner          = THIS_MODULE,
 418         .open           = bch2_dump_open,
 419         .release        = bch2_dump_release,
 420         .read           = bch2_read_bfloat_failed,
 421 };
 422
 423 void bch2_fs_debug_exit(struct bch_fs *c)
 424 {
 425         if (!IS_ERR_OR_NULL(c->debug))
 426                 debugfs_remove_recursive(c->debug);
 427 }
 428
 429 void bch2_fs_debug_init(struct bch_fs *c)
 430 {
 431         struct btree_debug *bd;
 432         char name[100];
 433
 434         if (IS_ERR_OR_NULL(bch_debug))
 435                 return;
 436
 437         snprintf(name, sizeof(name), "%pU", c->sb.user_uuid.b);
 438         c->debug = debugfs_create_dir(name, bch_debug);
 439         if (IS_ERR_OR_NULL(c->debug))
 440                 return;
 441
 442         for (bd = c->btree_debug;
 443              bd < c->btree_debug + ARRAY_SIZE(c->btree_debug);
 444              bd++) {
 445                 bd->id = bd - c->btree_debug;
 446                 bd->btree = debugfs_create_file(bch2_btree_ids[bd->id],
 447                                                 0400, c->debug, bd,
 448                                                 &btree_debug_ops);
 449
 450                 snprintf(name, sizeof(name), "%s-formats",
 451                          bch2_btree_ids[bd->id]);
 452
 453                 bd->btree_format = debugfs_create_file(name, 0400, c->debug, bd,
 454                                                        &btree_format_debug_ops);
 455
 456                 snprintf(name, sizeof(name), "%s-bfloat-failed",
 457                          bch2_btree_ids[bd->id]);
 458
 459                 bd->failed = debugfs_create_file(name, 0400, c->debug, bd,
 460                                                  &bfloat_failed_debug_ops);
 461         }
 462 }
 463
 464 #endif
 465
 466 void bch2_debug_exit(void)
 467 {
 468         if (!IS_ERR_OR_NULL(bch_debug))
 469                 debugfs_remove_recursive(bch_debug);
 470 }
 471
 472 int __init bch2_debug_init(void)
 473 {
 474         int ret = 0;
 475
 476         bch_debug = debugfs_create_dir("bcachefs", NULL);
 477         return ret;
 478 }