git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/debug.c

   1 /*
   2  * Assorted bcachefs debug code
   3  *
   4  * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
   5  * Copyright 2012 Google, Inc.
   6  */
   7
   8 #include "bcachefs.h"
   9 #include "bkey_methods.h"
  10 #include "btree_cache.h"
  11 #include "btree_io.h"
  12 #include "btree_iter.h"
  13 #include "btree_update.h"
  14 #include "buckets.h"
  15 #include "debug.h"
  16 #include "error.h"
  17 #include "extents.h"
  18 #include "fsck.h"
  19 #include "inode.h"
  20 #include "io.h"
  21 #include "super.h"
  22
  23 #include <linux/console.h>
  24 #include <linux/debugfs.h>
  25 #include <linux/module.h>
  26 #include <linux/random.h>
  27 #include <linux/seq_file.h>
  28
  29 static struct dentry *bch_debug;
  30
  31 #ifdef CONFIG_BCACHEFS_DEBUG
  32
  33 void __bch2_btree_verify(struct bch_fs *c, struct btree *b)
  34 {
  35         struct btree *v = c->verify_data;
  36         struct btree_node *n_ondisk, *n_sorted, *n_inmemory;
  37         struct bset *sorted, *inmemory;
  38         struct extent_ptr_decoded pick;
  39         struct bch_dev *ca;
  40         struct bio *bio;
  41
  42         if (c->opts.nochanges)
  43                 return;
  44
  45         btree_node_io_lock(b);
  46         mutex_lock(&c->verify_lock);
  47
  48         n_ondisk = c->verify_ondisk;
  49         n_sorted = c->verify_data->data;
  50         n_inmemory = b->data;
  51
  52         bkey_copy(&v->key, &b->key);
  53         v->written      = 0;
  54         v->level        = b->level;
  55         v->btree_id     = b->btree_id;
  56         bch2_btree_keys_init(v, &c->expensive_debug_checks);
  57
  58         if (bch2_btree_pick_ptr(c, b, NULL, &pick) <= 0)
  59                 return;
  60
  61         ca = bch_dev_bkey_exists(c, pick.ptr.dev);
  62         if (!bch2_dev_get_ioref(ca, READ))
  63                 return;
  64
  65         bio = bio_alloc_bioset(GFP_NOIO,
  66                         buf_pages(n_sorted, btree_bytes(c)),
  67                         &c->btree_bio);
  68         bio_set_dev(bio, ca->disk_sb.bdev);
  69         bio->bi_opf             = REQ_OP_READ|REQ_META;
  70         bio->bi_iter.bi_sector  = pick.ptr.offset;
  71         bio->bi_iter.bi_size    = btree_bytes(c);
  72         bch2_bio_map(bio, n_sorted);
  73
  74         submit_bio_wait(bio);
  75
  76         bio_put(bio);
  77         percpu_ref_put(&ca->io_ref);
  78
  79         memcpy(n_ondisk, n_sorted, btree_bytes(c));
  80
  81         if (bch2_btree_node_read_done(c, v, false))
  82                 goto out;
  83
  84         n_sorted = c->verify_data->data;
  85         sorted = &n_sorted->keys;
  86         inmemory = &n_inmemory->keys;
  87
  88         if (inmemory->u64s != sorted->u64s ||
  89             memcmp(inmemory->start,
  90                    sorted->start,
  91                    vstruct_end(inmemory) - (void *) inmemory->start)) {
  92                 unsigned offset = 0, sectors;
  93                 struct bset *i;
  94                 unsigned j;
  95
  96                 console_lock();
  97
  98                 printk(KERN_ERR "*** in memory:\n");
  99                 bch2_dump_bset(b, inmemory, 0);
 100
 101                 printk(KERN_ERR "*** read back in:\n");
 102                 bch2_dump_bset(v, sorted, 0);
 103
 104                 while (offset < b->written) {
 105                         if (!offset ) {
 106                                 i = &n_ondisk->keys;
 107                                 sectors = vstruct_blocks(n_ondisk, c->block_bits) <<
 108                                         c->block_bits;
 109                         } else {
 110                                 struct btree_node_entry *bne =
 111                                         (void *) n_ondisk + (offset << 9);
 112                                 i = &bne->keys;
 113
 114                                 sectors = vstruct_blocks(bne, c->block_bits) <<
 115                                         c->block_bits;
 116                         }
 117
 118                         printk(KERN_ERR "*** on disk block %u:\n", offset);
 119                         bch2_dump_bset(b, i, offset);
 120
 121                         offset += sectors;
 122                 }
 123
 124                 printk(KERN_ERR "*** block %u/%u not written\n",
 125                        offset >> c->block_bits, btree_blocks(c));
 126
 127                 for (j = 0; j < le16_to_cpu(inmemory->u64s); j++)
 128                         if (inmemory->_data[j] != sorted->_data[j])
 129                                 break;
 130
 131                 printk(KERN_ERR "b->written %u\n", b->written);
 132
 133                 console_unlock();
 134                 panic("verify failed at %u\n", j);
 135         }
 136 out:
 137         mutex_unlock(&c->verify_lock);
 138         btree_node_io_unlock(b);
 139 }
 140
 141 #endif
 142
 143 #ifdef CONFIG_DEBUG_FS
 144
 145 /* XXX: bch_fs refcounting */
 146
 147 struct dump_iter {
 148         struct bpos             from;
 149         struct bch_fs   *c;
 150         enum btree_id           id;
 151
 152         char                    buf[PAGE_SIZE];
 153         size_t                  bytes;  /* what's currently in buf */
 154
 155         char __user             *ubuf;  /* destination user buffer */
 156         size_t                  size;   /* size of requested read */
 157         ssize_t                 ret;    /* bytes read so far */
 158 };
 159
 160 static int flush_buf(struct dump_iter *i)
 161 {
 162         if (i->bytes) {
 163                 size_t bytes = min(i->bytes, i->size);
 164                 int err = copy_to_user(i->ubuf, i->buf, bytes);
 165
 166                 if (err)
 167                         return err;
 168
 169                 i->ret   += bytes;
 170                 i->ubuf  += bytes;
 171                 i->size  -= bytes;
 172                 i->bytes -= bytes;
 173                 memmove(i->buf, i->buf + bytes, i->bytes);
 174         }
 175
 176         return 0;
 177 }
 178
 179 static int bch2_dump_open(struct inode *inode, struct file *file)
 180 {
 181         struct btree_debug *bd = inode->i_private;
 182         struct dump_iter *i;
 183
 184         i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
 185         if (!i)
 186                 return -ENOMEM;
 187
 188         file->private_data = i;
 189         i->from = POS_MIN;
 190         i->c    = container_of(bd, struct bch_fs, btree_debug[bd->id]);
 191         i->id   = bd->id;
 192
 193         return 0;
 194 }
 195
 196 static int bch2_dump_release(struct inode *inode, struct file *file)
 197 {
 198         kfree(file->private_data);
 199         return 0;
 200 }
 201
 202 static ssize_t bch2_read_btree(struct file *file, char __user *buf,
 203                                size_t size, loff_t *ppos)
 204 {
 205         struct dump_iter *i = file->private_data;
 206         struct btree_iter iter;
 207         struct bkey_s_c k;
 208         int err;
 209
 210         i->ubuf = buf;
 211         i->size = size;
 212         i->ret  = 0;
 213
 214         err = flush_buf(i);
 215         if (err)
 216                 return err;
 217
 218         if (!i->size)
 219                 return i->ret;
 220
 221         bch2_btree_iter_init(&iter, i->c, i->id, i->from, BTREE_ITER_PREFETCH);
 222         k = bch2_btree_iter_peek(&iter);
 223
 224         while (k.k && !(err = btree_iter_err(k))) {
 225                 bch2_bkey_val_to_text(&PBUF(i->buf), i->c,
 226                                       bkey_type(0, i->id), k);
 227                 i->bytes = strlen(i->buf);
 228                 BUG_ON(i->bytes >= PAGE_SIZE);
 229                 i->buf[i->bytes] = '\n';
 230                 i->bytes++;
 231
 232                 k = bch2_btree_iter_next(&iter);
 233                 i->from = iter.pos;
 234
 235                 err = flush_buf(i);
 236                 if (err)
 237                         break;
 238
 239                 if (!i->size)
 240                         break;
 241         }
 242         bch2_btree_iter_unlock(&iter);
 243
 244         return err < 0 ? err : i->ret;
 245 }
 246
 247 static const struct file_operations btree_debug_ops = {
 248         .owner          = THIS_MODULE,
 249         .open           = bch2_dump_open,
 250         .release        = bch2_dump_release,
 251         .read           = bch2_read_btree,
 252 };
 253
 254 static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
 255                                        size_t size, loff_t *ppos)
 256 {
 257         struct dump_iter *i = file->private_data;
 258         struct btree_iter iter;
 259         struct btree *b;
 260         int err;
 261
 262         i->ubuf = buf;
 263         i->size = size;
 264         i->ret  = 0;
 265
 266         err = flush_buf(i);
 267         if (err)
 268                 return err;
 269
 270         if (!i->size || !bkey_cmp(POS_MAX, i->from))
 271                 return i->ret;
 272
 273         for_each_btree_node(&iter, i->c, i->id, i->from, 0, b) {
 274                 bch2_btree_node_to_text(&PBUF(i->buf), i->c, b);
 275                 i->bytes = strlen(i->buf);
 276                 err = flush_buf(i);
 277                 if (err)
 278                         break;
 279
 280                 /*
 281                  * can't easily correctly restart a btree node traversal across
 282                  * all nodes, meh
 283                  */
 284                 i->from = bkey_cmp(POS_MAX, b->key.k.p)
 285                         ? bkey_successor(b->key.k.p)
 286                         : b->key.k.p;
 287
 288                 if (!i->size)
 289                         break;
 290         }
 291         bch2_btree_iter_unlock(&iter);
 292
 293         return err < 0 ? err : i->ret;
 294 }
 295
 296 static const struct file_operations btree_format_debug_ops = {
 297         .owner          = THIS_MODULE,
 298         .open           = bch2_dump_open,
 299         .release        = bch2_dump_release,
 300         .read           = bch2_read_btree_formats,
 301 };
 302
 303 static ssize_t bch2_read_bfloat_failed(struct file *file, char __user *buf,
 304                                        size_t size, loff_t *ppos)
 305 {
 306         struct dump_iter *i = file->private_data;
 307         struct btree_iter iter;
 308         struct bkey_s_c k;
 309         struct btree *prev_node = NULL;
 310         int err;
 311
 312         i->ubuf = buf;
 313         i->size = size;
 314         i->ret  = 0;
 315
 316         err = flush_buf(i);
 317         if (err)
 318                 return err;
 319
 320         if (!i->size)
 321                 return i->ret;
 322
 323         bch2_btree_iter_init(&iter, i->c, i->id, i->from, BTREE_ITER_PREFETCH);
 324
 325         while ((k = bch2_btree_iter_peek(&iter)).k &&
 326                !(err = btree_iter_err(k))) {
 327                 struct btree_iter_level *l = &iter.l[0];
 328                 struct bkey_packed *_k =
 329                         bch2_btree_node_iter_peek(&l->iter, l->b);
 330
 331                 if (l->b != prev_node) {
 332                         bch2_btree_node_to_text(&PBUF(i->buf), i->c, l->b);
 333                         i->bytes = strlen(i->buf);
 334                         err = flush_buf(i);
 335                         if (err)
 336                                 break;
 337                 }
 338                 prev_node = l->b;
 339
 340                 bch2_bfloat_to_text(&PBUF(i->buf), l->b, _k);
 341                 i->bytes = strlen(i->buf);
 342                 err = flush_buf(i);
 343                 if (err)
 344                         break;
 345
 346                 bch2_btree_iter_next(&iter);
 347                 i->from = iter.pos;
 348
 349                 err = flush_buf(i);
 350                 if (err)
 351                         break;
 352
 353                 if (!i->size)
 354                         break;
 355         }
 356         bch2_btree_iter_unlock(&iter);
 357
 358         return err < 0 ? err : i->ret;
 359 }
 360
 361 static const struct file_operations bfloat_failed_debug_ops = {
 362         .owner          = THIS_MODULE,
 363         .open           = bch2_dump_open,
 364         .release        = bch2_dump_release,
 365         .read           = bch2_read_bfloat_failed,
 366 };
 367
 368 void bch2_fs_debug_exit(struct bch_fs *c)
 369 {
 370         if (!IS_ERR_OR_NULL(c->debug))
 371                 debugfs_remove_recursive(c->debug);
 372 }
 373
 374 void bch2_fs_debug_init(struct bch_fs *c)
 375 {
 376         struct btree_debug *bd;
 377         char name[100];
 378
 379         if (IS_ERR_OR_NULL(bch_debug))
 380                 return;
 381
 382         snprintf(name, sizeof(name), "%pU", c->sb.user_uuid.b);
 383         c->debug = debugfs_create_dir(name, bch_debug);
 384         if (IS_ERR_OR_NULL(c->debug))
 385                 return;
 386
 387         for (bd = c->btree_debug;
 388              bd < c->btree_debug + ARRAY_SIZE(c->btree_debug);
 389              bd++) {
 390                 bd->id = bd - c->btree_debug;
 391                 bd->btree = debugfs_create_file(bch2_btree_ids[bd->id],
 392                                                 0400, c->debug, bd,
 393                                                 &btree_debug_ops);
 394
 395                 snprintf(name, sizeof(name), "%s-formats",
 396                          bch2_btree_ids[bd->id]);
 397
 398                 bd->btree_format = debugfs_create_file(name, 0400, c->debug, bd,
 399                                                        &btree_format_debug_ops);
 400
 401                 snprintf(name, sizeof(name), "%s-bfloat-failed",
 402                          bch2_btree_ids[bd->id]);
 403
 404                 bd->failed = debugfs_create_file(name, 0400, c->debug, bd,
 405                                                  &bfloat_failed_debug_ops);
 406         }
 407 }
 408
 409 #endif
 410
 411 void bch2_debug_exit(void)
 412 {
 413         if (!IS_ERR_OR_NULL(bch_debug))
 414                 debugfs_remove_recursive(bch_debug);
 415 }
 416
 417 int __init bch2_debug_init(void)
 418 {
 419         int ret = 0;
 420
 421         bch_debug = debugfs_create_dir("bcachefs", NULL);
 422         return ret;
 423 }