]> git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/inode.c
Update bcachefs sources to 18686af684 bcachefs: Inode backpointers
[bcachefs-tools-debian] / libbcachefs / inode.c
1 // SPDX-License-Identifier: GPL-2.0
2
3 #include "bcachefs.h"
4 #include "btree_key_cache.h"
5 #include "bkey_methods.h"
6 #include "btree_update.h"
7 #include "error.h"
8 #include "extents.h"
9 #include "inode.h"
10 #include "str_hash.h"
11 #include "varint.h"
12
13 #include <linux/random.h>
14
15 #include <asm/unaligned.h>
16
17 const char * const bch2_inode_opts[] = {
18 #define x(name, ...)    #name,
19         BCH_INODE_OPTS()
20 #undef  x
21         NULL,
22 };
23
24 static const u8 byte_table[8] = { 1, 2, 3, 4, 6, 8, 10, 13 };
25 static const u8 bits_table[8] = {
26         1  * 8 - 1,
27         2  * 8 - 2,
28         3  * 8 - 3,
29         4  * 8 - 4,
30         6  * 8 - 5,
31         8  * 8 - 6,
32         10 * 8 - 7,
33         13 * 8 - 8,
34 };
35
36 static int inode_encode_field(u8 *out, u8 *end, u64 hi, u64 lo)
37 {
38         __be64 in[2] = { cpu_to_be64(hi), cpu_to_be64(lo), };
39         unsigned shift, bytes, bits = likely(!hi)
40                 ? fls64(lo)
41                 : fls64(hi) + 64;
42
43         for (shift = 1; shift <= 8; shift++)
44                 if (bits < bits_table[shift - 1])
45                         goto got_shift;
46
47         BUG();
48 got_shift:
49         bytes = byte_table[shift - 1];
50
51         BUG_ON(out + bytes > end);
52
53         memcpy(out, (u8 *) in + 16 - bytes, bytes);
54         *out |= (1 << 8) >> shift;
55
56         return bytes;
57 }
58
59 static int inode_decode_field(const u8 *in, const u8 *end,
60                               u64 out[2], unsigned *out_bits)
61 {
62         __be64 be[2] = { 0, 0 };
63         unsigned bytes, shift;
64         u8 *p;
65
66         if (in >= end)
67                 return -1;
68
69         if (!*in)
70                 return -1;
71
72         /*
73          * position of highest set bit indicates number of bytes:
74          * shift = number of bits to remove in high byte:
75          */
76         shift   = 8 - __fls(*in); /* 1 <= shift <= 8 */
77         bytes   = byte_table[shift - 1];
78
79         if (in + bytes > end)
80                 return -1;
81
82         p = (u8 *) be + 16 - bytes;
83         memcpy(p, in, bytes);
84         *p ^= (1 << 8) >> shift;
85
86         out[0] = be64_to_cpu(be[0]);
87         out[1] = be64_to_cpu(be[1]);
88         *out_bits = out[0] ? 64 + fls64(out[0]) : fls64(out[1]);
89
90         return bytes;
91 }
92
93 static noinline void bch2_inode_pack_v1(struct bkey_inode_buf *packed,
94                                         const struct bch_inode_unpacked *inode)
95 {
96         struct bkey_i_inode *k = &packed->inode;
97         u8 *out = k->v.fields;
98         u8 *end = (void *) &packed[1];
99         u8 *last_nonzero_field = out;
100         unsigned nr_fields = 0, last_nonzero_fieldnr = 0;
101         unsigned bytes;
102
103 #define x(_name, _bits)                                                 \
104         out += inode_encode_field(out, end, 0, inode->_name);           \
105         nr_fields++;                                                    \
106                                                                         \
107         if (inode->_name) {                                             \
108                 last_nonzero_field = out;                               \
109                 last_nonzero_fieldnr = nr_fields;                       \
110         }
111
112         BCH_INODE_FIELDS()
113 #undef  x
114
115         out = last_nonzero_field;
116         nr_fields = last_nonzero_fieldnr;
117
118         bytes = out - (u8 *) &packed->inode.v;
119         set_bkey_val_bytes(&packed->inode.k, bytes);
120         memset_u64s_tail(&packed->inode.v, 0, bytes);
121
122         SET_INODE_NR_FIELDS(&k->v, nr_fields);
123 }
124
125 static void bch2_inode_pack_v2(struct bkey_inode_buf *packed,
126                                const struct bch_inode_unpacked *inode)
127 {
128         struct bkey_i_inode *k = &packed->inode;
129         u8 *out = k->v.fields;
130         u8 *end = (void *) &packed[1];
131         u8 *last_nonzero_field = out;
132         unsigned nr_fields = 0, last_nonzero_fieldnr = 0;
133         unsigned bytes;
134         int ret;
135
136 #define x(_name, _bits)                                                 \
137         nr_fields++;                                                    \
138                                                                         \
139         if (inode->_name) {                                             \
140                 ret = bch2_varint_encode(out, inode->_name);            \
141                 out += ret;                                             \
142                                                                         \
143                 if (_bits > 64)                                         \
144                         *out++ = 0;                                     \
145                                                                         \
146                 last_nonzero_field = out;                               \
147                 last_nonzero_fieldnr = nr_fields;                       \
148         } else {                                                        \
149                 *out++ = 0;                                             \
150                                                                         \
151                 if (_bits > 64)                                         \
152                         *out++ = 0;                                     \
153         }
154
155         BCH_INODE_FIELDS()
156 #undef  x
157         BUG_ON(out > end);
158
159         out = last_nonzero_field;
160         nr_fields = last_nonzero_fieldnr;
161
162         bytes = out - (u8 *) &packed->inode.v;
163         set_bkey_val_bytes(&packed->inode.k, bytes);
164         memset_u64s_tail(&packed->inode.v, 0, bytes);
165
166         SET_INODE_NR_FIELDS(&k->v, nr_fields);
167 }
168
169 void bch2_inode_pack(struct bch_fs *c,
170                      struct bkey_inode_buf *packed,
171                      const struct bch_inode_unpacked *inode)
172 {
173         bkey_inode_init(&packed->inode.k_i);
174         packed->inode.k.p.offset        = inode->bi_inum;
175         packed->inode.v.bi_hash_seed    = inode->bi_hash_seed;
176         packed->inode.v.bi_flags        = cpu_to_le32(inode->bi_flags);
177         packed->inode.v.bi_mode         = cpu_to_le16(inode->bi_mode);
178
179         if (c->sb.features & (1ULL << BCH_FEATURE_new_varint)) {
180                 SET_INODE_NEW_VARINT(&packed->inode.v, true);
181                 bch2_inode_pack_v2(packed, inode);
182         } else {
183                 bch2_inode_pack_v1(packed, inode);
184         }
185
186         if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG)) {
187                 struct bch_inode_unpacked unpacked;
188
189                 int ret = bch2_inode_unpack(inode_i_to_s_c(&packed->inode),
190                                            &unpacked);
191                 BUG_ON(ret);
192                 BUG_ON(unpacked.bi_inum         != inode->bi_inum);
193                 BUG_ON(unpacked.bi_hash_seed    != inode->bi_hash_seed);
194                 BUG_ON(unpacked.bi_mode         != inode->bi_mode);
195
196 #define x(_name, _bits) if (unpacked._name != inode->_name)             \
197                         panic("unpacked %llu should be %llu",           \
198                               (u64) unpacked._name, (u64) inode->_name);
199                 BCH_INODE_FIELDS()
200 #undef  x
201         }
202 }
203
204 static noinline int bch2_inode_unpack_v1(struct bkey_s_c_inode inode,
205                                 struct bch_inode_unpacked *unpacked)
206 {
207         const u8 *in = inode.v->fields;
208         const u8 *end = bkey_val_end(inode);
209         u64 field[2];
210         unsigned fieldnr = 0, field_bits;
211         int ret;
212
213 #define x(_name, _bits)                                 \
214         if (fieldnr++ == INODE_NR_FIELDS(inode.v)) {                    \
215                 memset(&unpacked->_name, 0,                             \
216                        sizeof(*unpacked) -                              \
217                        offsetof(struct bch_inode_unpacked, _name));     \
218                 return 0;                                               \
219         }                                                               \
220                                                                         \
221         ret = inode_decode_field(in, end, field, &field_bits);          \
222         if (ret < 0)                                                    \
223                 return ret;                                             \
224                                                                         \
225         if (field_bits > sizeof(unpacked->_name) * 8)                   \
226                 return -1;                                              \
227                                                                         \
228         unpacked->_name = field[1];                                     \
229         in += ret;
230
231         BCH_INODE_FIELDS()
232 #undef  x
233
234         /* XXX: signal if there were more fields than expected? */
235         return 0;
236 }
237
238 static int bch2_inode_unpack_v2(struct bkey_s_c_inode inode,
239                                 struct bch_inode_unpacked *unpacked)
240 {
241         const u8 *in = inode.v->fields;
242         const u8 *end = bkey_val_end(inode);
243         unsigned fieldnr = 0;
244         int ret;
245         u64 v[2];
246
247 #define x(_name, _bits)                                                 \
248         if (fieldnr < INODE_NR_FIELDS(inode.v)) {                       \
249                 ret = bch2_varint_decode(in, end, &v[0]);               \
250                 if (ret < 0)                                            \
251                         return ret;                                     \
252                 in += ret;                                              \
253                                                                         \
254                 if (_bits > 64) {                                       \
255                         ret = bch2_varint_decode(in, end, &v[1]);       \
256                         if (ret < 0)                                    \
257                                 return ret;                             \
258                         in += ret;                                      \
259                 } else {                                                \
260                         v[1] = 0;                                       \
261                 }                                                       \
262         } else {                                                        \
263                 v[0] = v[1] = 0;                                        \
264         }                                                               \
265                                                                         \
266         unpacked->_name = v[0];                                         \
267         if (v[1] || v[0] != unpacked->_name)                            \
268                 return -1;                                              \
269         fieldnr++;
270
271         BCH_INODE_FIELDS()
272 #undef  x
273
274         /* XXX: signal if there were more fields than expected? */
275         return 0;
276 }
277
278 int bch2_inode_unpack(struct bkey_s_c_inode inode,
279                       struct bch_inode_unpacked *unpacked)
280 {
281         unpacked->bi_inum       = inode.k->p.offset;
282         unpacked->bi_hash_seed  = inode.v->bi_hash_seed;
283         unpacked->bi_flags      = le32_to_cpu(inode.v->bi_flags);
284         unpacked->bi_mode       = le16_to_cpu(inode.v->bi_mode);
285
286         if (INODE_NEW_VARINT(inode.v)) {
287                 return bch2_inode_unpack_v2(inode, unpacked);
288         } else {
289                 return bch2_inode_unpack_v1(inode, unpacked);
290         }
291
292         return 0;
293 }
294
295 struct btree_iter *bch2_inode_peek(struct btree_trans *trans,
296                                    struct bch_inode_unpacked *inode,
297                                    u64 inum, unsigned flags)
298 {
299         struct btree_iter *iter;
300         struct bkey_s_c k;
301         int ret;
302
303         iter = bch2_trans_get_iter(trans, BTREE_ID_inodes, POS(0, inum),
304                                    BTREE_ITER_CACHED|flags);
305         k = bch2_btree_iter_peek_cached(iter);
306         ret = bkey_err(k);
307         if (ret)
308                 goto err;
309
310         ret = k.k->type == KEY_TYPE_inode ? 0 : -EIO;
311         if (ret)
312                 goto err;
313
314         ret = bch2_inode_unpack(bkey_s_c_to_inode(k), inode);
315         if (ret)
316                 goto err;
317
318         return iter;
319 err:
320         bch2_trans_iter_put(trans, iter);
321         return ERR_PTR(ret);
322 }
323
324 int bch2_inode_write(struct btree_trans *trans,
325                      struct btree_iter *iter,
326                      struct bch_inode_unpacked *inode)
327 {
328         struct bkey_inode_buf *inode_p;
329
330         inode_p = bch2_trans_kmalloc(trans, sizeof(*inode_p));
331         if (IS_ERR(inode_p))
332                 return PTR_ERR(inode_p);
333
334         bch2_inode_pack(trans->c, inode_p, inode);
335         inode_p->inode.k.p.snapshot = iter->snapshot;
336         bch2_trans_update(trans, iter, &inode_p->inode.k_i, 0);
337         return 0;
338 }
339
340 const char *bch2_inode_invalid(const struct bch_fs *c, struct bkey_s_c k)
341 {
342                 struct bkey_s_c_inode inode = bkey_s_c_to_inode(k);
343                 struct bch_inode_unpacked unpacked;
344
345         if (k.k->p.inode)
346                 return "nonzero k.p.inode";
347
348         if (bkey_val_bytes(k.k) < sizeof(struct bch_inode))
349                 return "incorrect value size";
350
351         if (k.k->p.offset < BLOCKDEV_INODE_MAX)
352                 return "fs inode in blockdev range";
353
354         if (INODE_STR_HASH(inode.v) >= BCH_STR_HASH_NR)
355                 return "invalid str hash type";
356
357         if (bch2_inode_unpack(inode, &unpacked))
358                 return "invalid variable length fields";
359
360         if (unpacked.bi_data_checksum >= BCH_CSUM_OPT_NR + 1)
361                 return "invalid data checksum type";
362
363         if (unpacked.bi_compression >= BCH_COMPRESSION_OPT_NR + 1)
364                 return "invalid data checksum type";
365
366         if ((unpacked.bi_flags & BCH_INODE_UNLINKED) &&
367             unpacked.bi_nlink != 0)
368                 return "flagged as unlinked but bi_nlink != 0";
369
370         return NULL;
371 }
372
373 void bch2_inode_to_text(struct printbuf *out, struct bch_fs *c,
374                        struct bkey_s_c k)
375 {
376         struct bkey_s_c_inode inode = bkey_s_c_to_inode(k);
377         struct bch_inode_unpacked unpacked;
378
379         if (bch2_inode_unpack(inode, &unpacked)) {
380                 pr_buf(out, "(unpack error)");
381                 return;
382         }
383
384         pr_buf(out, "mode: %o ", unpacked.bi_mode);
385
386 #define x(_name, _bits)                                         \
387         pr_buf(out, #_name ": %llu ", (u64) unpacked._name);
388         BCH_INODE_FIELDS()
389 #undef  x
390 }
391
392 const char *bch2_inode_generation_invalid(const struct bch_fs *c,
393                                           struct bkey_s_c k)
394 {
395         if (k.k->p.inode)
396                 return "nonzero k.p.inode";
397
398         if (bkey_val_bytes(k.k) != sizeof(struct bch_inode_generation))
399                 return "incorrect value size";
400
401         return NULL;
402 }
403
404 void bch2_inode_generation_to_text(struct printbuf *out, struct bch_fs *c,
405                                    struct bkey_s_c k)
406 {
407         struct bkey_s_c_inode_generation gen = bkey_s_c_to_inode_generation(k);
408
409         pr_buf(out, "generation: %u", le32_to_cpu(gen.v->bi_generation));
410 }
411
412 void bch2_inode_init_early(struct bch_fs *c,
413                            struct bch_inode_unpacked *inode_u)
414 {
415         enum bch_str_hash_type str_hash =
416                 bch2_str_hash_opt_to_type(c, c->opts.str_hash);
417
418         memset(inode_u, 0, sizeof(*inode_u));
419
420         /* ick */
421         inode_u->bi_flags |= str_hash << INODE_STR_HASH_OFFSET;
422         get_random_bytes(&inode_u->bi_hash_seed,
423                          sizeof(inode_u->bi_hash_seed));
424 }
425
426 void bch2_inode_init_late(struct bch_inode_unpacked *inode_u, u64 now,
427                           uid_t uid, gid_t gid, umode_t mode, dev_t rdev,
428                           struct bch_inode_unpacked *parent)
429 {
430         inode_u->bi_mode        = mode;
431         inode_u->bi_uid         = uid;
432         inode_u->bi_gid         = gid;
433         inode_u->bi_dev         = rdev;
434         inode_u->bi_atime       = now;
435         inode_u->bi_mtime       = now;
436         inode_u->bi_ctime       = now;
437         inode_u->bi_otime       = now;
438
439         if (parent && parent->bi_mode & S_ISGID) {
440                 inode_u->bi_gid = parent->bi_gid;
441                 if (S_ISDIR(mode))
442                         inode_u->bi_mode |= S_ISGID;
443         }
444
445         if (parent) {
446 #define x(_name, ...)   inode_u->bi_##_name = parent->bi_##_name;
447                 BCH_INODE_OPTS()
448 #undef x
449         }
450 }
451
452 void bch2_inode_init(struct bch_fs *c, struct bch_inode_unpacked *inode_u,
453                      uid_t uid, gid_t gid, umode_t mode, dev_t rdev,
454                      struct bch_inode_unpacked *parent)
455 {
456         bch2_inode_init_early(c, inode_u);
457         bch2_inode_init_late(inode_u, bch2_current_time(c),
458                              uid, gid, mode, rdev, parent);
459 }
460
461 static inline u32 bkey_generation(struct bkey_s_c k)
462 {
463         switch (k.k->type) {
464         case KEY_TYPE_inode:
465                 BUG();
466         case KEY_TYPE_inode_generation:
467                 return le32_to_cpu(bkey_s_c_to_inode_generation(k).v->bi_generation);
468         default:
469                 return 0;
470         }
471 }
472
473 struct btree_iter *bch2_inode_create(struct btree_trans *trans,
474                                      struct bch_inode_unpacked *inode_u)
475 {
476         struct bch_fs *c = trans->c;
477         struct btree_iter *iter = NULL;
478         struct bkey_s_c k;
479         u64 min, max, start, *hint;
480         int ret;
481
482         u64 cpu = raw_smp_processor_id();
483         unsigned bits = (c->opts.inodes_32bit
484                 ? 31 : 63) - c->inode_shard_bits;
485
486         min = (cpu << bits);
487         max = (cpu << bits) | ~(ULLONG_MAX << bits);
488
489         min = max_t(u64, min, BLOCKDEV_INODE_MAX);
490         hint = c->unused_inode_hints + cpu;
491
492         start = READ_ONCE(*hint);
493
494         if (start >= max || start < min)
495                 start = min;
496 again:
497         for_each_btree_key(trans, iter, BTREE_ID_inodes, POS(0, start),
498                            BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) {
499                 if (bkey_cmp(iter->pos, POS(0, max)) > 0)
500                         break;
501
502                 /*
503                  * There's a potential cache coherency issue with the btree key
504                  * cache code here - we're iterating over the btree, skipping
505                  * that cache. We should never see an empty slot that isn't
506                  * actually empty due to a pending update in the key cache
507                  * because the update that creates the inode isn't done with a
508                  * cached iterator, but - better safe than sorry, check the
509                  * cache before using a slot:
510                  */
511                 if (k.k->type != KEY_TYPE_inode &&
512                     !bch2_btree_key_cache_find(c, BTREE_ID_inodes, iter->pos))
513                         goto found_slot;
514         }
515
516         bch2_trans_iter_put(trans, iter);
517
518         if (ret)
519                 return ERR_PTR(ret);
520
521         if (start != min) {
522                 /* Retry from start */
523                 start = min;
524                 goto again;
525         }
526
527         return ERR_PTR(-ENOSPC);
528 found_slot:
529         *hint                   = k.k->p.offset;
530         inode_u->bi_inum        = k.k->p.offset;
531         inode_u->bi_generation  = bkey_generation(k);
532         return iter;
533 }
534
535 int bch2_inode_rm(struct bch_fs *c, u64 inode_nr, bool cached)
536 {
537         struct btree_trans trans;
538         struct btree_iter *iter = NULL;
539         struct bkey_i_inode_generation delete;
540         struct bpos start = POS(inode_nr, 0);
541         struct bpos end = POS(inode_nr + 1, 0);
542         struct bch_inode_unpacked inode_u;
543         struct bkey_s_c k;
544         int ret;
545
546         bch2_trans_init(&trans, c, 0, 0);
547
548         /*
549          * If this was a directory, there shouldn't be any real dirents left -
550          * but there could be whiteouts (from hash collisions) that we should
551          * delete:
552          *
553          * XXX: the dirent could ideally would delete whiteouts when they're no
554          * longer needed
555          */
556         ret   = bch2_btree_delete_range_trans(&trans, BTREE_ID_extents,
557                                               start, end, NULL) ?:
558                 bch2_btree_delete_range_trans(&trans, BTREE_ID_xattrs,
559                                               start, end, NULL) ?:
560                 bch2_btree_delete_range_trans(&trans, BTREE_ID_dirents,
561                                               start, end, NULL);
562         if (ret)
563                 goto err;
564 retry:
565         bch2_trans_begin(&trans);
566
567         if (cached) {
568                 iter = bch2_trans_get_iter(&trans, BTREE_ID_inodes, POS(0, inode_nr),
569                                            BTREE_ITER_CACHED|BTREE_ITER_INTENT);
570                 k = bch2_btree_iter_peek_cached(iter);
571         } else {
572                 iter = bch2_trans_get_iter(&trans, BTREE_ID_inodes, POS(0, inode_nr),
573                                            BTREE_ITER_SLOTS|BTREE_ITER_INTENT);
574                 k = bch2_btree_iter_peek_slot(iter);
575         }
576
577         ret = bkey_err(k);
578         if (ret)
579                 goto err;
580
581         if (k.k->type != KEY_TYPE_inode) {
582                 bch2_fs_inconsistent(trans.c,
583                                      "inode %llu not found when deleting",
584                                      inode_nr);
585                 ret = -EIO;
586                 goto err;
587         }
588
589         bch2_inode_unpack(bkey_s_c_to_inode(k), &inode_u);
590
591         bkey_inode_generation_init(&delete.k_i);
592         delete.k.p = iter->pos;
593         delete.v.bi_generation = cpu_to_le32(inode_u.bi_generation + 1);
594
595         bch2_trans_update(&trans, iter, &delete.k_i, 0);
596
597         ret = bch2_trans_commit(&trans, NULL, NULL,
598                                 BTREE_INSERT_NOFAIL);
599 err:
600         bch2_trans_iter_put(&trans, iter);
601         if (ret == -EINTR)
602                 goto retry;
603
604         bch2_trans_exit(&trans);
605         return ret;
606 }
607
608 int __bch2_inode_find_by_inum_trans(struct btree_trans *trans, u64 inode_nr,
609                                     struct bch_inode_unpacked *inode,
610                                     unsigned flags)
611 {
612         struct btree_iter *iter;
613         struct bkey_s_c k;
614         int ret;
615
616         iter = bch2_trans_get_iter(trans, BTREE_ID_inodes,
617                         POS(0, inode_nr), flags);
618         k = (flags & BTREE_ITER_TYPE) == BTREE_ITER_CACHED
619                 ? bch2_btree_iter_peek_cached(iter)
620                 : bch2_btree_iter_peek_slot(iter);
621         ret = bkey_err(k);
622         if (ret)
623                 goto err;
624
625         ret = k.k->type == KEY_TYPE_inode
626                 ? bch2_inode_unpack(bkey_s_c_to_inode(k), inode)
627                 : -ENOENT;
628 err:
629         bch2_trans_iter_put(trans, iter);
630         return ret;
631 }
632
633 int bch2_inode_find_by_inum_trans(struct btree_trans *trans, u64 inode_nr,
634                                   struct bch_inode_unpacked *inode)
635 {
636         return __bch2_inode_find_by_inum_trans(trans, inode_nr,
637                                                inode, BTREE_ITER_CACHED);
638
639 }
640
641 int bch2_inode_find_by_inum(struct bch_fs *c, u64 inode_nr,
642                             struct bch_inode_unpacked *inode)
643 {
644         return bch2_trans_do(c, NULL, NULL, 0,
645                 bch2_inode_find_by_inum_trans(&trans, inode_nr, inode));
646 }