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 #ifdef CONFIG_BCACHEFS_DEBUG
  33
  34 void __bch2_btree_verify(struct bch_fs *c, struct btree *b)
  35 {
  36         struct btree *v = c->verify_data;
  37         struct btree_node *n_ondisk, *n_sorted, *n_inmemory;
  38         struct bset *sorted, *inmemory;
  39         struct extent_ptr_decoded pick;
  40         struct bch_dev *ca;
  41         struct bio *bio;
  42
  43         if (c->opts.nochanges)
  44                 return;
  45
  46         btree_node_io_lock(b);
  47         mutex_lock(&c->verify_lock);
  48
  49         n_ondisk = c->verify_ondisk;
  50         n_sorted = c->verify_data->data;
  51         n_inmemory = b->data;
  52
  53         bkey_copy(&v->key, &b->key);
  54         v->written      = 0;
  55         v->c.level      = b->c.level;
  56         v->c.btree_id   = b->c.btree_id;
  57         bch2_btree_keys_init(v, &c->expensive_debug_checks);
  58
  59         if (bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key),
  60                                        NULL, &pick) <= 0)
  61                 return;
  62
  63         ca = bch_dev_bkey_exists(c, pick.ptr.dev);
  64         if (!bch2_dev_get_ioref(ca, READ))
  65                 return;
  66
  67         bio = bio_alloc_bioset(GFP_NOIO,
  68                         buf_pages(n_sorted, btree_bytes(c)),
  69                         &c->btree_bio);
  70         bio_set_dev(bio, ca->disk_sb.bdev);
  71         bio->bi_opf             = REQ_OP_READ|REQ_META;
  72         bio->bi_iter.bi_sector  = pick.ptr.offset;
  73         bch2_bio_map(bio, n_sorted, btree_bytes(c));
  74
  75         submit_bio_wait(bio);
  76
  77         bio_put(bio);
  78         percpu_ref_put(&ca->io_ref);
  79
  80         memcpy(n_ondisk, n_sorted, btree_bytes(c));
  81
  82         if (bch2_btree_node_read_done(c, v, false))
  83                 goto out;
  84
  85         n_sorted = c->verify_data->data;
  86         sorted = &n_sorted->keys;
  87         inmemory = &n_inmemory->keys;
  88
  89         if (inmemory->u64s != sorted->u64s ||
  90             memcmp(inmemory->start,
  91                    sorted->start,
  92                    vstruct_end(inmemory) - (void *) inmemory->start)) {
  93                 unsigned offset = 0, sectors;
  94                 struct bset *i;
  95                 unsigned j;
  96
  97                 console_lock();
  98
  99                 printk(KERN_ERR "*** in memory:\n");
 100                 bch2_dump_bset(b, inmemory, 0);
 101
 102                 printk(KERN_ERR "*** read back in:\n");
 103                 bch2_dump_bset(v, sorted, 0);
 104
 105                 while (offset < b->written) {
 106                         if (!offset ) {
 107                                 i = &n_ondisk->keys;
 108                                 sectors = vstruct_blocks(n_ondisk, c->block_bits) <<
 109                                         c->block_bits;
 110                         } else {
 111                                 struct btree_node_entry *bne =
 112                                         (void *) n_ondisk + (offset << 9);
 113                                 i = &bne->keys;
 114
 115                                 sectors = vstruct_blocks(bne, c->block_bits) <<
 116                                         c->block_bits;
 117                         }
 118
 119                         printk(KERN_ERR "*** on disk block %u:\n", offset);
 120                         bch2_dump_bset(b, i, offset);
 121
 122                         offset += sectors;
 123                 }
 124
 125                 printk(KERN_ERR "*** block %u/%u not written\n",
 126                        offset >> c->block_bits, btree_blocks(c));
 127
 128                 for (j = 0; j < le16_to_cpu(inmemory->u64s); j++)
 129                         if (inmemory->_data[j] != sorted->_data[j])
 130                                 break;
 131
 132                 printk(KERN_ERR "b->written %u\n", b->written);
 133
 134                 console_unlock();
 135                 panic("verify failed at %u\n", j);
 136         }
 137 out:
 138         mutex_unlock(&c->verify_lock);
 139         btree_node_io_unlock(b);
 140 }
 141
 142 #endif
 143
 144 #ifdef CONFIG_DEBUG_FS
 145
 146 /* XXX: bch_fs refcounting */
 147
 148 struct dump_iter {
 149         struct bpos             from;
 150         struct bch_fs   *c;
 151         enum btree_id           id;
 152
 153         char                    buf[PAGE_SIZE];
 154         size_t                  bytes;  /* what's currently in buf */
 155
 156         char __user             *ubuf;  /* destination user buffer */
 157         size_t                  size;   /* size of requested read */
 158         ssize_t                 ret;    /* bytes read so far */
 159 };
 160
 161 static int flush_buf(struct dump_iter *i)
 162 {
 163         if (i->bytes) {
 164                 size_t bytes = min(i->bytes, i->size);
 165                 int err = copy_to_user(i->ubuf, i->buf, bytes);
 166
 167                 if (err)
 168                         return err;
 169
 170                 i->ret   += bytes;
 171                 i->ubuf  += bytes;
 172                 i->size  -= bytes;
 173                 i->bytes -= bytes;
 174                 memmove(i->buf, i->buf + bytes, i->bytes);
 175         }
 176
 177         return 0;
 178 }
 179
 180 static int bch2_dump_open(struct inode *inode, struct file *file)
 181 {
 182         struct btree_debug *bd = inode->i_private;
 183         struct dump_iter *i;
 184
 185         i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
 186         if (!i)
 187                 return -ENOMEM;
 188
 189         file->private_data = i;
 190         i->from = POS_MIN;
 191         i->c    = container_of(bd, struct bch_fs, btree_debug[bd->id]);
 192         i->id   = bd->id;
 193
 194         return 0;
 195 }
 196
 197 static int bch2_dump_release(struct inode *inode, struct file *file)
 198 {
 199         kfree(file->private_data);
 200         return 0;
 201 }
 202
 203 static ssize_t bch2_read_btree(struct file *file, char __user *buf,
 204                                size_t size, loff_t *ppos)
 205 {
 206         struct dump_iter *i = file->private_data;
 207         struct btree_trans trans;
 208         struct btree_iter *iter;
 209         struct bkey_s_c k;
 210         int err;
 211
 212         i->ubuf = buf;
 213         i->size = size;
 214         i->ret  = 0;
 215
 216         err = flush_buf(i);
 217         if (err)
 218                 return err;
 219
 220         if (!i->size)
 221                 return i->ret;
 222
 223         bch2_trans_init(&trans, i->c, 0, 0);
 224
 225         iter = bch2_trans_get_iter(&trans, i->id, i->from, BTREE_ITER_PREFETCH);
 226         k = bch2_btree_iter_peek(iter);
 227
 228         while (k.k && !(err = bkey_err(k))) {
 229                 bch2_bkey_val_to_text(&PBUF(i->buf), i->c, k);
 230                 i->bytes = strlen(i->buf);
 231                 BUG_ON(i->bytes >= PAGE_SIZE);
 232                 i->buf[i->bytes] = '\n';
 233                 i->bytes++;
 234
 235                 k = bch2_btree_iter_next(iter);
 236                 i->from = iter->pos;
 237
 238                 err = flush_buf(i);
 239                 if (err)
 240                         break;
 241
 242                 if (!i->size)
 243                         break;
 244         }
 245         bch2_trans_exit(&trans);
 246
 247         return err < 0 ? err : i->ret;
 248 }
 249
 250 static const struct file_operations btree_debug_ops = {
 251         .owner          = THIS_MODULE,
 252         .open           = bch2_dump_open,
 253         .release        = bch2_dump_release,
 254         .read           = bch2_read_btree,
 255 };
 256
 257 static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
 258                                        size_t size, loff_t *ppos)
 259 {
 260         struct dump_iter *i = file->private_data;
 261         struct btree_trans trans;
 262         struct btree_iter *iter;
 263         struct btree *b;
 264         int err;
 265
 266         i->ubuf = buf;
 267         i->size = size;
 268         i->ret  = 0;
 269
 270         err = flush_buf(i);
 271         if (err)
 272                 return err;
 273
 274         if (!i->size || !bkey_cmp(POS_MAX, i->from))
 275                 return i->ret;
 276
 277         bch2_trans_init(&trans, i->c, 0, 0);
 278
 279         for_each_btree_node(&trans, iter, i->id, i->from, 0, b) {
 280                 bch2_btree_node_to_text(&PBUF(i->buf), i->c, b);
 281                 i->bytes = strlen(i->buf);
 282                 err = flush_buf(i);
 283                 if (err)
 284                         break;
 285
 286                 /*
 287                  * can't easily correctly restart a btree node traversal across
 288                  * all nodes, meh
 289                  */
 290                 i->from = bkey_cmp(POS_MAX, b->key.k.p)
 291                         ? bkey_successor(b->key.k.p)
 292                         : b->key.k.p;
 293
 294                 if (!i->size)
 295                         break;
 296         }
 297         bch2_trans_exit(&trans);
 298
 299         return err < 0 ? err : i->ret;
 300 }
 301
 302 static const struct file_operations btree_format_debug_ops = {
 303         .owner          = THIS_MODULE,
 304         .open           = bch2_dump_open,
 305         .release        = bch2_dump_release,
 306         .read           = bch2_read_btree_formats,
 307 };
 308
 309 static ssize_t bch2_read_bfloat_failed(struct file *file, char __user *buf,
 310                                        size_t size, loff_t *ppos)
 311 {
 312         struct dump_iter *i = file->private_data;
 313         struct btree_trans trans;
 314         struct btree_iter *iter;
 315         struct bkey_s_c k;
 316         struct btree *prev_node = NULL;
 317         int err;
 318
 319         i->ubuf = buf;
 320         i->size = size;
 321         i->ret  = 0;
 322
 323         err = flush_buf(i);
 324         if (err)
 325                 return err;
 326
 327         if (!i->size)
 328                 return i->ret;
 329
 330         bch2_trans_init(&trans, i->c, 0, 0);
 331
 332         iter = bch2_trans_get_iter(&trans, i->id, i->from, BTREE_ITER_PREFETCH);
 333
 334         while ((k = bch2_btree_iter_peek(iter)).k &&
 335                !(err = bkey_err(k))) {
 336                 struct btree_iter_level *l = &iter->l[0];
 337                 struct bkey_packed *_k =
 338                         bch2_btree_node_iter_peek(&l->iter, l->b);
 339
 340                 if (l->b != prev_node) {
 341                         bch2_btree_node_to_text(&PBUF(i->buf), i->c, l->b);
 342                         i->bytes = strlen(i->buf);
 343                         err = flush_buf(i);
 344                         if (err)
 345                                 break;
 346                 }
 347                 prev_node = l->b;
 348
 349                 bch2_bfloat_to_text(&PBUF(i->buf), l->b, _k);
 350                 i->bytes = strlen(i->buf);
 351                 err = flush_buf(i);
 352                 if (err)
 353                         break;
 354
 355                 bch2_btree_iter_next(iter);
 356                 i->from = iter->pos;
 357
 358                 err = flush_buf(i);
 359                 if (err)
 360                         break;
 361
 362                 if (!i->size)
 363                         break;
 364         }
 365         bch2_trans_exit(&trans);
 366
 367         return err < 0 ? err : i->ret;
 368 }
 369
 370 static const struct file_operations bfloat_failed_debug_ops = {
 371         .owner          = THIS_MODULE,
 372         .open           = bch2_dump_open,
 373         .release        = bch2_dump_release,
 374         .read           = bch2_read_bfloat_failed,
 375 };
 376
 377 void bch2_fs_debug_exit(struct bch_fs *c)
 378 {
 379         if (!IS_ERR_OR_NULL(c->debug))
 380                 debugfs_remove_recursive(c->debug);
 381 }
 382
 383 void bch2_fs_debug_init(struct bch_fs *c)
 384 {
 385         struct btree_debug *bd;
 386         char name[100];
 387
 388         if (IS_ERR_OR_NULL(bch_debug))
 389                 return;
 390
 391         snprintf(name, sizeof(name), "%pU", c->sb.user_uuid.b);
 392         c->debug = debugfs_create_dir(name, bch_debug);
 393         if (IS_ERR_OR_NULL(c->debug))
 394                 return;
 395
 396         for (bd = c->btree_debug;
 397              bd < c->btree_debug + ARRAY_SIZE(c->btree_debug);
 398              bd++) {
 399                 bd->id = bd - c->btree_debug;
 400                 bd->btree = debugfs_create_file(bch2_btree_ids[bd->id],
 401                                                 0400, c->debug, bd,
 402                                                 &btree_debug_ops);
 403
 404                 snprintf(name, sizeof(name), "%s-formats",
 405                          bch2_btree_ids[bd->id]);
 406
 407                 bd->btree_format = debugfs_create_file(name, 0400, c->debug, bd,
 408                                                        &btree_format_debug_ops);
 409
 410                 snprintf(name, sizeof(name), "%s-bfloat-failed",
 411                          bch2_btree_ids[bd->id]);
 412
 413                 bd->failed = debugfs_create_file(name, 0400, c->debug, bd,
 414                                                  &bfloat_failed_debug_ops);
 415         }
 416 }
 417
 418 #endif
 419
 420 void bch2_debug_exit(void)
 421 {
 422         if (!IS_ERR_OR_NULL(bch_debug))
 423                 debugfs_remove_recursive(bch_debug);
 424 }
 425
 426 int __init bch2_debug_init(void)
 427 {
 428         int ret = 0;
 429
 430         bch_debug = debugfs_create_dir("bcachefs", NULL);
 431         return ret;
 432 }