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8#include "bcache.h"
9#include "btree.h"
10#include "debug.h"
11#include "request.h"
12
13#include <linux/console.h>
14#include <linux/debugfs.h>
15#include <linux/module.h>
16#include <linux/random.h>
17#include <linux/seq_file.h>
18
19static struct dentry *debug;
20
21const char *bch_ptr_status(struct cache_set *c, const struct bkey *k)
22{
23 unsigned i;
24
25 for (i = 0; i < KEY_PTRS(k); i++)
26 if (ptr_available(c, k, i)) {
27 struct cache *ca = PTR_CACHE(c, k, i);
28 size_t bucket = PTR_BUCKET_NR(c, k, i);
29 size_t r = bucket_remainder(c, PTR_OFFSET(k, i));
30
31 if (KEY_SIZE(k) + r > c->sb.bucket_size)
32 return "bad, length too big";
33 if (bucket < ca->sb.first_bucket)
34 return "bad, short offset";
35 if (bucket >= ca->sb.nbuckets)
36 return "bad, offset past end of device";
37 if (ptr_stale(c, k, i))
38 return "stale";
39 }
40
41 if (!bkey_cmp(k, &ZERO_KEY))
42 return "bad, null key";
43 if (!KEY_PTRS(k))
44 return "bad, no pointers";
45 if (!KEY_SIZE(k))
46 return "zeroed key";
47 return "";
48}
49
50int bch_bkey_to_text(char *buf, size_t size, const struct bkey *k)
51{
52 unsigned i = 0;
53 char *out = buf, *end = buf + size;
54
55#define p(...) (out += scnprintf(out, end - out, __VA_ARGS__))
56
57 p("%llu:%llu len %llu -> [", KEY_INODE(k), KEY_OFFSET(k), KEY_SIZE(k));
58
59 if (KEY_PTRS(k))
60 while (1) {
61 p("%llu:%llu gen %llu",
62 PTR_DEV(k, i), PTR_OFFSET(k, i), PTR_GEN(k, i));
63
64 if (++i == KEY_PTRS(k))
65 break;
66
67 p(", ");
68 }
69
70 p("]");
71
72 if (KEY_DIRTY(k))
73 p(" dirty");
74 if (KEY_CSUM(k))
75 p(" cs%llu %llx", KEY_CSUM(k), k->ptr[1]);
76#undef p
77 return out - buf;
78}
79
80int bch_btree_to_text(char *buf, size_t size, const struct btree *b)
81{
82 return scnprintf(buf, size, "%zu level %i/%i",
83 PTR_BUCKET_NR(b->c, &b->key, 0),
84 b->level, b->c->root ? b->c->root->level : -1);
85}
86
87#if defined(CONFIG_BCACHE_DEBUG) || defined(CONFIG_BCACHE_EDEBUG)
88
89static bool skipped_backwards(struct btree *b, struct bkey *k)
90{
91 return bkey_cmp(k, (!b->level)
92 ? &START_KEY(bkey_next(k))
93 : bkey_next(k)) > 0;
94}
95
96static void dump_bset(struct btree *b, struct bset *i)
97{
98 struct bkey *k;
99 unsigned j;
100 char buf[80];
101
102 for (k = i->start; k < end(i); k = bkey_next(k)) {
103 bch_bkey_to_text(buf, sizeof(buf), k);
104 printk(KERN_ERR "block %zu key %zi/%u: %s", index(i, b),
105 (uint64_t *) k - i->d, i->keys, buf);
106
107 for (j = 0; j < KEY_PTRS(k); j++) {
108 size_t n = PTR_BUCKET_NR(b->c, k, j);
109 printk(" bucket %zu", n);
110
111 if (n >= b->c->sb.first_bucket && n < b->c->sb.nbuckets)
112 printk(" prio %i",
113 PTR_BUCKET(b->c, k, j)->prio);
114 }
115
116 printk(" %s\n", bch_ptr_status(b->c, k));
117
118 if (bkey_next(k) < end(i) &&
119 skipped_backwards(b, k))
120 printk(KERN_ERR "Key skipped backwards\n");
121 }
122}
123
124#endif
125
126#ifdef CONFIG_BCACHE_DEBUG
127
128void bch_btree_verify(struct btree *b, struct bset *new)
129{
130 struct btree *v = b->c->verify_data;
131 struct closure cl;
132 closure_init_stack(&cl);
133
134 if (!b->c->verify)
135 return;
136
137 closure_wait_event(&b->io.wait, &cl,
138 atomic_read(&b->io.cl.remaining) == -1);
139
140 mutex_lock(&b->c->verify_lock);
141
142 bkey_copy(&v->key, &b->key);
143 v->written = 0;
144 v->level = b->level;
145
146 bch_btree_node_read(v);
147 closure_wait_event(&v->io.wait, &cl,
148 atomic_read(&b->io.cl.remaining) == -1);
149
150 if (new->keys != v->sets[0].data->keys ||
151 memcmp(new->start,
152 v->sets[0].data->start,
153 (void *) end(new) - (void *) new->start)) {
154 unsigned i, j;
155
156 console_lock();
157
158 printk(KERN_ERR "*** original memory node:\n");
159 for (i = 0; i <= b->nsets; i++)
160 dump_bset(b, b->sets[i].data);
161
162 printk(KERN_ERR "*** sorted memory node:\n");
163 dump_bset(b, new);
164
165 printk(KERN_ERR "*** on disk node:\n");
166 dump_bset(v, v->sets[0].data);
167
168 for (j = 0; j < new->keys; j++)
169 if (new->d[j] != v->sets[0].data->d[j])
170 break;
171
172 console_unlock();
173 panic("verify failed at %u\n", j);
174 }
175
176 mutex_unlock(&b->c->verify_lock);
177}
178
179static void data_verify_endio(struct bio *bio, int error)
180{
181 struct closure *cl = bio->bi_private;
182 closure_put(cl);
183}
184
185void bch_data_verify(struct search *s)
186{
187 char name[BDEVNAME_SIZE];
188 struct cached_dev *dc = container_of(s->d, struct cached_dev, disk);
189 struct closure *cl = &s->cl;
190 struct bio *check;
191 struct bio_vec *bv;
192 int i;
193
194 if (!s->unaligned_bvec)
195 bio_for_each_segment(bv, s->orig_bio, i)
196 bv->bv_offset = 0, bv->bv_len = PAGE_SIZE;
197
198 check = bio_clone(s->orig_bio, GFP_NOIO);
199 if (!check)
200 return;
201
202 if (bio_alloc_pages(check, GFP_NOIO))
203 goto out_put;
204
205 check->bi_rw = READ_SYNC;
206 check->bi_private = cl;
207 check->bi_end_io = data_verify_endio;
208
209 closure_bio_submit(check, cl, &dc->disk);
210 closure_sync(cl);
211
212 bio_for_each_segment(bv, s->orig_bio, i) {
213 void *p1 = kmap(bv->bv_page);
214 void *p2 = kmap(check->bi_io_vec[i].bv_page);
215
216 if (memcmp(p1 + bv->bv_offset,
217 p2 + bv->bv_offset,
218 bv->bv_len))
219 printk(KERN_ERR
220 "bcache (%s): verify failed at sector %llu\n",
221 bdevname(dc->bdev, name),
222 (uint64_t) s->orig_bio->bi_sector);
223
224 kunmap(bv->bv_page);
225 kunmap(check->bi_io_vec[i].bv_page);
226 }
227
228 __bio_for_each_segment(bv, check, i, 0)
229 __free_page(bv->bv_page);
230out_put:
231 bio_put(check);
232}
233
234#endif
235
236#ifdef CONFIG_BCACHE_EDEBUG
237
238unsigned bch_count_data(struct btree *b)
239{
240 unsigned ret = 0;
241 struct btree_iter iter;
242 struct bkey *k;
243
244 if (!b->level)
245 for_each_key(b, k, &iter)
246 ret += KEY_SIZE(k);
247 return ret;
248}
249
250static void vdump_bucket_and_panic(struct btree *b, const char *fmt,
251 va_list args)
252{
253 unsigned i;
254 char buf[80];
255
256 console_lock();
257
258 for (i = 0; i <= b->nsets; i++)
259 dump_bset(b, b->sets[i].data);
260
261 vprintk(fmt, args);
262
263 console_unlock();
264
265 bch_btree_to_text(buf, sizeof(buf), b);
266 panic("at %s\n", buf);
267}
268
269void bch_check_key_order_msg(struct btree *b, struct bset *i,
270 const char *fmt, ...)
271{
272 struct bkey *k;
273
274 if (!i->keys)
275 return;
276
277 for (k = i->start; bkey_next(k) < end(i); k = bkey_next(k))
278 if (skipped_backwards(b, k)) {
279 va_list args;
280 va_start(args, fmt);
281
282 vdump_bucket_and_panic(b, fmt, args);
283 va_end(args);
284 }
285}
286
287void bch_check_keys(struct btree *b, const char *fmt, ...)
288{
289 va_list args;
290 struct bkey *k, *p = NULL;
291 struct btree_iter iter;
292
293 if (b->level)
294 return;
295
296 for_each_key(b, k, &iter) {
297 if (p && bkey_cmp(&START_KEY(p), &START_KEY(k)) > 0) {
298 printk(KERN_ERR "Keys out of order:\n");
299 goto bug;
300 }
301
302 if (bch_ptr_invalid(b, k))
303 continue;
304
305 if (p && bkey_cmp(p, &START_KEY(k)) > 0) {
306 printk(KERN_ERR "Overlapping keys:\n");
307 goto bug;
308 }
309 p = k;
310 }
311 return;
312bug:
313 va_start(args, fmt);
314 vdump_bucket_and_panic(b, fmt, args);
315 va_end(args);
316}
317
318#endif
319
320#ifdef CONFIG_DEBUG_FS
321
322
323
324struct dump_iterator {
325 char buf[PAGE_SIZE];
326 size_t bytes;
327 struct cache_set *c;
328 struct keybuf keys;
329};
330
331static bool dump_pred(struct keybuf *buf, struct bkey *k)
332{
333 return true;
334}
335
336static ssize_t bch_dump_read(struct file *file, char __user *buf,
337 size_t size, loff_t *ppos)
338{
339 struct dump_iterator *i = file->private_data;
340 ssize_t ret = 0;
341 char kbuf[80];
342
343 while (size) {
344 struct keybuf_key *w;
345 unsigned bytes = min(i->bytes, size);
346
347 int err = copy_to_user(buf, i->buf, bytes);
348 if (err)
349 return err;
350
351 ret += bytes;
352 buf += bytes;
353 size -= bytes;
354 i->bytes -= bytes;
355 memmove(i->buf, i->buf + bytes, i->bytes);
356
357 if (i->bytes)
358 break;
359
360 w = bch_keybuf_next_rescan(i->c, &i->keys, &MAX_KEY, dump_pred);
361 if (!w)
362 break;
363
364 bch_bkey_to_text(kbuf, sizeof(kbuf), &w->key);
365 i->bytes = snprintf(i->buf, PAGE_SIZE, "%s\n", kbuf);
366 bch_keybuf_del(&i->keys, w);
367 }
368
369 return ret;
370}
371
372static int bch_dump_open(struct inode *inode, struct file *file)
373{
374 struct cache_set *c = inode->i_private;
375 struct dump_iterator *i;
376
377 i = kzalloc(sizeof(struct dump_iterator), GFP_KERNEL);
378 if (!i)
379 return -ENOMEM;
380
381 file->private_data = i;
382 i->c = c;
383 bch_keybuf_init(&i->keys);
384 i->keys.last_scanned = KEY(0, 0, 0);
385
386 return 0;
387}
388
389static int bch_dump_release(struct inode *inode, struct file *file)
390{
391 kfree(file->private_data);
392 return 0;
393}
394
395static const struct file_operations cache_set_debug_ops = {
396 .owner = THIS_MODULE,
397 .open = bch_dump_open,
398 .read = bch_dump_read,
399 .release = bch_dump_release
400};
401
402void bch_debug_init_cache_set(struct cache_set *c)
403{
404 if (!IS_ERR_OR_NULL(debug)) {
405 char name[50];
406 snprintf(name, 50, "bcache-%pU", c->sb.set_uuid);
407
408 c->debug = debugfs_create_file(name, 0400, debug, c,
409 &cache_set_debug_ops);
410 }
411}
412
413#endif
414
415void bch_debug_exit(void)
416{
417 if (!IS_ERR_OR_NULL(debug))
418 debugfs_remove_recursive(debug);
419}
420
421int __init bch_debug_init(struct kobject *kobj)
422{
423 int ret = 0;
424
425 debug = debugfs_create_dir("bcache", NULL);
426 return ret;
427}
428
