1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Assorted bcache debug code 4 * 5 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> 6 * Copyright 2012 Google, Inc. 7 */ 8 9 #include "bcache.h" 10 #include "btree.h" 11 #include "debug.h" 12 #include "extents.h" 13 14 #include <linux/console.h> 15 #include <linux/debugfs.h> 16 #include <linux/module.h> 17 #include <linux/random.h> 18 #include <linux/seq_file.h> 19 20 static struct dentry *debug; 21 22 #ifdef CONFIG_BCACHE_DEBUG 23 24 #define for_each_written_bset(b, start, i) \ 25 for (i = (start); \ 26 (void *) i < (void *) (start) + (KEY_SIZE(&b->key) << 9) &&\ 27 i->seq == (start)->seq; \ 28 i = (void *) i + set_blocks(i, block_bytes(b->c)) * \ 29 block_bytes(b->c)) 30 31 void bch_btree_verify(struct btree *b) 32 { 33 struct btree *v = b->c->verify_data; 34 struct bset *ondisk, *sorted, *inmemory; 35 struct bio *bio; 36 37 if (!b->c->verify || !b->c->verify_ondisk) 38 return; 39 40 down(&b->io_mutex); 41 mutex_lock(&b->c->verify_lock); 42 43 ondisk = b->c->verify_ondisk; 44 sorted = b->c->verify_data->keys.set->data; 45 inmemory = b->keys.set->data; 46 47 bkey_copy(&v->key, &b->key); 48 v->written = 0; 49 v->level = b->level; 50 v->keys.ops = b->keys.ops; 51 52 bio = bch_bbio_alloc(b->c); 53 bio_set_dev(bio, PTR_CACHE(b->c, &b->key, 0)->bdev); 54 bio->bi_iter.bi_sector = PTR_OFFSET(&b->key, 0); 55 bio->bi_iter.bi_size = KEY_SIZE(&v->key) << 9; 56 bio->bi_opf = REQ_OP_READ | REQ_META; 57 bch_bio_map(bio, sorted); 58 59 submit_bio_wait(bio); 60 bch_bbio_free(bio, b->c); 61 62 memcpy(ondisk, sorted, KEY_SIZE(&v->key) << 9); 63 64 bch_btree_node_read_done(v); 65 sorted = v->keys.set->data; 66 67 if (inmemory->keys != sorted->keys || 68 memcmp(inmemory->start, 69 sorted->start, 70 (void *) bset_bkey_last(inmemory) - (void *) inmemory->start)) { 71 struct bset *i; 72 unsigned j; 73 74 console_lock(); 75 76 printk(KERN_ERR "*** in memory:\n"); 77 bch_dump_bset(&b->keys, inmemory, 0); 78 79 printk(KERN_ERR "*** read back in:\n"); 80 bch_dump_bset(&v->keys, sorted, 0); 81 82 for_each_written_bset(b, ondisk, i) { 83 unsigned block = ((void *) i - (void *) ondisk) / 84 block_bytes(b->c); 85 86 printk(KERN_ERR "*** on disk block %u:\n", block); 87 bch_dump_bset(&b->keys, i, block); 88 } 89 90 printk(KERN_ERR "*** block %zu not written\n", 91 ((void *) i - (void *) ondisk) / block_bytes(b->c)); 92 93 for (j = 0; j < inmemory->keys; j++) 94 if (inmemory->d[j] != sorted->d[j]) 95 break; 96 97 printk(KERN_ERR "b->written %u\n", b->written); 98 99 console_unlock(); 100 panic("verify failed at %u\n", j); 101 } 102 103 mutex_unlock(&b->c->verify_lock); 104 up(&b->io_mutex); 105 } 106 107 void bch_data_verify(struct cached_dev *dc, struct bio *bio) 108 { 109 char name[BDEVNAME_SIZE]; 110 struct bio *check; 111 struct bio_vec bv, cbv; 112 struct bvec_iter iter, citer = { 0 }; 113 114 check = bio_clone_kmalloc(bio, GFP_NOIO); 115 if (!check) 116 return; 117 check->bi_opf = REQ_OP_READ; 118 119 if (bch_bio_alloc_pages(check, GFP_NOIO)) 120 goto out_put; 121 122 submit_bio_wait(check); 123 124 citer.bi_size = UINT_MAX; 125 bio_for_each_segment(bv, bio, iter) { 126 void *p1 = kmap_atomic(bv.bv_page); 127 void *p2; 128 129 cbv = bio_iter_iovec(check, citer); 130 p2 = page_address(cbv.bv_page); 131 132 cache_set_err_on(memcmp(p1 + bv.bv_offset, 133 p2 + bv.bv_offset, 134 bv.bv_len), 135 dc->disk.c, 136 "verify failed at dev %s sector %llu", 137 bdevname(dc->bdev, name), 138 (uint64_t) bio->bi_iter.bi_sector); 139 140 kunmap_atomic(p1); 141 bio_advance_iter(check, &citer, bv.bv_len); 142 } 143 144 bio_free_pages(check); 145 out_put: 146 bio_put(check); 147 } 148 149 #endif 150 151 #ifdef CONFIG_DEBUG_FS 152 153 /* XXX: cache set refcounting */ 154 155 struct dump_iterator { 156 char buf[PAGE_SIZE]; 157 size_t bytes; 158 struct cache_set *c; 159 struct keybuf keys; 160 }; 161 162 static bool dump_pred(struct keybuf *buf, struct bkey *k) 163 { 164 return true; 165 } 166 167 static ssize_t bch_dump_read(struct file *file, char __user *buf, 168 size_t size, loff_t *ppos) 169 { 170 struct dump_iterator *i = file->private_data; 171 ssize_t ret = 0; 172 char kbuf[80]; 173 174 while (size) { 175 struct keybuf_key *w; 176 unsigned bytes = min(i->bytes, size); 177 178 int err = copy_to_user(buf, i->buf, bytes); 179 if (err) 180 return err; 181 182 ret += bytes; 183 buf += bytes; 184 size -= bytes; 185 i->bytes -= bytes; 186 memmove(i->buf, i->buf + bytes, i->bytes); 187 188 if (i->bytes) 189 break; 190 191 w = bch_keybuf_next_rescan(i->c, &i->keys, &MAX_KEY, dump_pred); 192 if (!w) 193 break; 194 195 bch_extent_to_text(kbuf, sizeof(kbuf), &w->key); 196 i->bytes = snprintf(i->buf, PAGE_SIZE, "%s\n", kbuf); 197 bch_keybuf_del(&i->keys, w); 198 } 199 200 return ret; 201 } 202 203 static int bch_dump_open(struct inode *inode, struct file *file) 204 { 205 struct cache_set *c = inode->i_private; 206 struct dump_iterator *i; 207 208 i = kzalloc(sizeof(struct dump_iterator), GFP_KERNEL); 209 if (!i) 210 return -ENOMEM; 211 212 file->private_data = i; 213 i->c = c; 214 bch_keybuf_init(&i->keys); 215 i->keys.last_scanned = KEY(0, 0, 0); 216 217 return 0; 218 } 219 220 static int bch_dump_release(struct inode *inode, struct file *file) 221 { 222 kfree(file->private_data); 223 return 0; 224 } 225 226 static const struct file_operations cache_set_debug_ops = { 227 .owner = THIS_MODULE, 228 .open = bch_dump_open, 229 .read = bch_dump_read, 230 .release = bch_dump_release 231 }; 232 233 void bch_debug_init_cache_set(struct cache_set *c) 234 { 235 if (!IS_ERR_OR_NULL(debug)) { 236 char name[50]; 237 snprintf(name, 50, "bcache-%pU", c->sb.set_uuid); 238 239 c->debug = debugfs_create_file(name, 0400, debug, c, 240 &cache_set_debug_ops); 241 } 242 } 243 244 #endif 245 246 void bch_debug_exit(void) 247 { 248 if (!IS_ERR_OR_NULL(debug)) 249 debugfs_remove_recursive(debug); 250 } 251 252 int __init bch_debug_init(struct kobject *kobj) 253 { 254 debug = debugfs_create_dir("bcache", NULL); 255 256 return IS_ERR_OR_NULL(debug); 257 } 258