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 struct dentry *bcache_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 struct bio *check; 110 struct bio_vec bv, cbv; 111 struct bvec_iter iter, citer = { 0 }; 112 113 check = bio_clone_kmalloc(bio, GFP_NOIO); 114 if (!check) 115 return; 116 check->bi_opf = REQ_OP_READ; 117 118 if (bch_bio_alloc_pages(check, GFP_NOIO)) 119 goto out_put; 120 121 submit_bio_wait(check); 122 123 citer.bi_size = UINT_MAX; 124 bio_for_each_segment(bv, bio, iter) { 125 void *p1 = kmap_atomic(bv.bv_page); 126 void *p2; 127 128 cbv = bio_iter_iovec(check, citer); 129 p2 = page_address(cbv.bv_page); 130 131 cache_set_err_on(memcmp(p1 + bv.bv_offset, 132 p2 + bv.bv_offset, 133 bv.bv_len), 134 dc->disk.c, 135 "verify failed at dev %s sector %llu", 136 dc->backing_dev_name, 137 (uint64_t) bio->bi_iter.bi_sector); 138 139 kunmap_atomic(p1); 140 bio_advance_iter(check, &citer, bv.bv_len); 141 } 142 143 bio_free_pages(check); 144 out_put: 145 bio_put(check); 146 } 147 148 #endif 149 150 #ifdef CONFIG_DEBUG_FS 151 152 /* XXX: cache set refcounting */ 153 154 struct dump_iterator { 155 char buf[PAGE_SIZE]; 156 size_t bytes; 157 struct cache_set *c; 158 struct keybuf keys; 159 }; 160 161 static bool dump_pred(struct keybuf *buf, struct bkey *k) 162 { 163 return true; 164 } 165 166 static ssize_t bch_dump_read(struct file *file, char __user *buf, 167 size_t size, loff_t *ppos) 168 { 169 struct dump_iterator *i = file->private_data; 170 ssize_t ret = 0; 171 char kbuf[80]; 172 173 while (size) { 174 struct keybuf_key *w; 175 unsigned bytes = min(i->bytes, size); 176 177 int err = copy_to_user(buf, i->buf, bytes); 178 if (err) 179 return err; 180 181 ret += bytes; 182 buf += bytes; 183 size -= bytes; 184 i->bytes -= bytes; 185 memmove(i->buf, i->buf + bytes, i->bytes); 186 187 if (i->bytes) 188 break; 189 190 w = bch_keybuf_next_rescan(i->c, &i->keys, &MAX_KEY, dump_pred); 191 if (!w) 192 break; 193 194 bch_extent_to_text(kbuf, sizeof(kbuf), &w->key); 195 i->bytes = snprintf(i->buf, PAGE_SIZE, "%s\n", kbuf); 196 bch_keybuf_del(&i->keys, w); 197 } 198 199 return ret; 200 } 201 202 static int bch_dump_open(struct inode *inode, struct file *file) 203 { 204 struct cache_set *c = inode->i_private; 205 struct dump_iterator *i; 206 207 i = kzalloc(sizeof(struct dump_iterator), GFP_KERNEL); 208 if (!i) 209 return -ENOMEM; 210 211 file->private_data = i; 212 i->c = c; 213 bch_keybuf_init(&i->keys); 214 i->keys.last_scanned = KEY(0, 0, 0); 215 216 return 0; 217 } 218 219 static int bch_dump_release(struct inode *inode, struct file *file) 220 { 221 kfree(file->private_data); 222 return 0; 223 } 224 225 static const struct file_operations cache_set_debug_ops = { 226 .owner = THIS_MODULE, 227 .open = bch_dump_open, 228 .read = bch_dump_read, 229 .release = bch_dump_release 230 }; 231 232 void bch_debug_init_cache_set(struct cache_set *c) 233 { 234 if (!IS_ERR_OR_NULL(bcache_debug)) { 235 char name[50]; 236 snprintf(name, 50, "bcache-%pU", c->sb.set_uuid); 237 238 c->debug = debugfs_create_file(name, 0400, bcache_debug, c, 239 &cache_set_debug_ops); 240 } 241 } 242 243 #endif 244 245 void bch_debug_exit(void) 246 { 247 if (!IS_ERR_OR_NULL(bcache_debug)) 248 debugfs_remove_recursive(bcache_debug); 249 } 250 251 int __init bch_debug_init(struct kobject *kobj) 252 { 253 if (!IS_ENABLED(CONFIG_DEBUG_FS)) 254 return 0; 255 256 bcache_debug = debugfs_create_dir("bcache", NULL); 257 return IS_ERR_OR_NULL(bcache_debug); 258 } 259