1// SPDX-License-Identifier: GPL-2.0
2#include "bcachefs.h"
3#include "bkey_buf.h"
4#include "btree_update.h"
5#include "buckets.h"
6#include "error.h"
7#include "extents.h"
8#include "inode.h"
9#include "io_misc.h"
10#include "io_write.h"
11#include "rebalance.h"
12#include "reflink.h"
13#include "subvolume.h"
14#include "super-io.h"
15
16#include <linux/sched/signal.h>
17
18static inline unsigned bkey_type_to_indirect(const struct bkey *k)
19{
20 switch (k->type) {
21 case KEY_TYPE_extent:
22 return KEY_TYPE_reflink_v;
23 case KEY_TYPE_inline_data:
24 return KEY_TYPE_indirect_inline_data;
25 default:
26 return 0;
27 }
28}
29
30/* reflink pointers */
31
32int bch2_reflink_p_invalid(struct bch_fs *c, struct bkey_s_c k,
33 enum bkey_invalid_flags flags,
34 struct printbuf *err)
35{
36 struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
37 int ret = 0;
38
39 bkey_fsck_err_on(le64_to_cpu(p.v->idx) < le32_to_cpu(p.v->front_pad),
40 c, err, reflink_p_front_pad_bad,
41 "idx < front_pad (%llu < %u)",
42 le64_to_cpu(p.v->idx), le32_to_cpu(p.v->front_pad));
43fsck_err:
44 return ret;
45}
46
47void bch2_reflink_p_to_text(struct printbuf *out, struct bch_fs *c,
48 struct bkey_s_c k)
49{
50 struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
51
52 prt_printf(out, "idx %llu front_pad %u back_pad %u",
53 le64_to_cpu(p.v->idx),
54 le32_to_cpu(p.v->front_pad),
55 le32_to_cpu(p.v->back_pad));
56}
57
58bool bch2_reflink_p_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
59{
60 struct bkey_s_reflink_p l = bkey_s_to_reflink_p(k: _l);
61 struct bkey_s_c_reflink_p r = bkey_s_c_to_reflink_p(k: _r);
62
63 /*
64 * Disabled for now, the triggers code needs to be reworked for merging
65 * of reflink pointers to work:
66 */
67 return false;
68
69 if (le64_to_cpu(l.v->idx) + l.k->size != le64_to_cpu(r.v->idx))
70 return false;
71
72 bch2_key_resize(k: l.k, new_size: l.k->size + r.k->size);
73 return true;
74}
75
76static int trans_trigger_reflink_p_segment(struct btree_trans *trans,
77 struct bkey_s_c_reflink_p p,
78 u64 *idx, unsigned flags)
79{
80 struct bch_fs *c = trans->c;
81 struct btree_iter iter;
82 struct bkey_i *k;
83 __le64 *refcount;
84 int add = !(flags & BTREE_TRIGGER_OVERWRITE) ? 1 : -1;
85 struct printbuf buf = PRINTBUF;
86 int ret;
87
88 k = bch2_bkey_get_mut_noupdate(trans, iter: &iter,
89 btree_id: BTREE_ID_reflink, POS(0, *idx),
90 flags: BTREE_ITER_WITH_UPDATES);
91 ret = PTR_ERR_OR_ZERO(ptr: k);
92 if (ret)
93 goto err;
94
95 refcount = bkey_refcount(k: bkey_i_to_s(k));
96 if (!refcount) {
97 bch2_bkey_val_to_text(&buf, c, p.s_c);
98 bch2_trans_inconsistent(trans,
99 "nonexistent indirect extent at %llu while marking\n %s",
100 *idx, buf.buf);
101 ret = -EIO;
102 goto err;
103 }
104
105 if (!*refcount && (flags & BTREE_TRIGGER_OVERWRITE)) {
106 bch2_bkey_val_to_text(&buf, c, p.s_c);
107 bch2_trans_inconsistent(trans,
108 "indirect extent refcount underflow at %llu while marking\n %s",
109 *idx, buf.buf);
110 ret = -EIO;
111 goto err;
112 }
113
114 if (flags & BTREE_TRIGGER_INSERT) {
115 struct bch_reflink_p *v = (struct bch_reflink_p *) p.v;
116 u64 pad;
117
118 pad = max_t(s64, le32_to_cpu(v->front_pad),
119 le64_to_cpu(v->idx) - bkey_start_offset(&k->k));
120 BUG_ON(pad > U32_MAX);
121 v->front_pad = cpu_to_le32(pad);
122
123 pad = max_t(s64, le32_to_cpu(v->back_pad),
124 k->k.p.offset - p.k->size - le64_to_cpu(v->idx));
125 BUG_ON(pad > U32_MAX);
126 v->back_pad = cpu_to_le32(pad);
127 }
128
129 le64_add_cpu(var: refcount, val: add);
130
131 bch2_btree_iter_set_pos_to_extent_start(iter: &iter);
132 ret = bch2_trans_update(trans, &iter, k, 0);
133 if (ret)
134 goto err;
135
136 *idx = k->k.p.offset;
137err:
138 bch2_trans_iter_exit(trans, &iter);
139 printbuf_exit(&buf);
140 return ret;
141}
142
143static s64 gc_trigger_reflink_p_segment(struct btree_trans *trans,
144 struct bkey_s_c_reflink_p p,
145 u64 *idx, unsigned flags, size_t r_idx)
146{
147 struct bch_fs *c = trans->c;
148 struct reflink_gc *r;
149 int add = !(flags & BTREE_TRIGGER_OVERWRITE) ? 1 : -1;
150 u64 start = le64_to_cpu(p.v->idx);
151 u64 end = le64_to_cpu(p.v->idx) + p.k->size;
152 u64 next_idx = end + le32_to_cpu(p.v->back_pad);
153 s64 ret = 0;
154 struct printbuf buf = PRINTBUF;
155
156 if (r_idx >= c->reflink_gc_nr)
157 goto not_found;
158
159 r = genradix_ptr(&c->reflink_gc_table, r_idx);
160 next_idx = min(next_idx, r->offset - r->size);
161 if (*idx < next_idx)
162 goto not_found;
163
164 BUG_ON((s64) r->refcount + add < 0);
165
166 r->refcount += add;
167 *idx = r->offset;
168 return 0;
169not_found:
170 if (fsck_err(c, reflink_p_to_missing_reflink_v,
171 "pointer to missing indirect extent\n"
172 " %s\n"
173 " missing range %llu-%llu",
174 (bch2_bkey_val_to_text(&buf, c, p.s_c), buf.buf),
175 *idx, next_idx)) {
176 struct bkey_i *update = bch2_bkey_make_mut_noupdate(trans, k: p.s_c);
177 ret = PTR_ERR_OR_ZERO(ptr: update);
178 if (ret)
179 goto err;
180
181 if (next_idx <= start) {
182 bkey_i_to_reflink_p(k: update)->v.front_pad = cpu_to_le32(start - next_idx);
183 } else if (*idx >= end) {
184 bkey_i_to_reflink_p(k: update)->v.back_pad = cpu_to_le32(*idx - end);
185 } else {
186 bkey_error_init(k: update);
187 update->k.p = p.k->p;
188 update->k.size = p.k->size;
189 set_bkey_val_u64s(k: &update->k, val_u64s: 0);
190 }
191
192 ret = bch2_btree_insert_trans(trans, BTREE_ID_extents, update, BTREE_TRIGGER_NORUN);
193 }
194
195 *idx = next_idx;
196err:
197fsck_err:
198 printbuf_exit(&buf);
199 return ret;
200}
201
202static int __trigger_reflink_p(struct btree_trans *trans,
203 enum btree_id btree_id, unsigned level,
204 struct bkey_s_c k, unsigned flags)
205{
206 struct bch_fs *c = trans->c;
207 struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
208 int ret = 0;
209
210 u64 idx = le64_to_cpu(p.v->idx) - le32_to_cpu(p.v->front_pad);
211 u64 end = le64_to_cpu(p.v->idx) + p.k->size + le32_to_cpu(p.v->back_pad);
212
213 if (flags & BTREE_TRIGGER_TRANSACTIONAL) {
214 while (idx < end && !ret)
215 ret = trans_trigger_reflink_p_segment(trans, p, idx: &idx, flags);
216 }
217
218 if (flags & BTREE_TRIGGER_GC) {
219 size_t l = 0, r = c->reflink_gc_nr;
220
221 while (l < r) {
222 size_t m = l + (r - l) / 2;
223 struct reflink_gc *ref = genradix_ptr(&c->reflink_gc_table, m);
224 if (ref->offset <= idx)
225 l = m + 1;
226 else
227 r = m;
228 }
229
230 while (idx < end && !ret)
231 ret = gc_trigger_reflink_p_segment(trans, p, idx: &idx, flags, r_idx: l++);
232 }
233
234 return ret;
235}
236
237int bch2_trigger_reflink_p(struct btree_trans *trans,
238 enum btree_id btree_id, unsigned level,
239 struct bkey_s_c old,
240 struct bkey_s new,
241 unsigned flags)
242{
243 if ((flags & BTREE_TRIGGER_TRANSACTIONAL) &&
244 (flags & BTREE_TRIGGER_INSERT)) {
245 struct bch_reflink_p *v = bkey_s_to_reflink_p(k: new).v;
246
247 v->front_pad = v->back_pad = 0;
248 }
249
250 return trigger_run_overwrite_then_insert(__trigger_reflink_p, trans, btree_id, level, old, new, flags);
251}
252
253/* indirect extents */
254
255int bch2_reflink_v_invalid(struct bch_fs *c, struct bkey_s_c k,
256 enum bkey_invalid_flags flags,
257 struct printbuf *err)
258{
259 return bch2_bkey_ptrs_invalid(c, k, flags, err);
260}
261
262void bch2_reflink_v_to_text(struct printbuf *out, struct bch_fs *c,
263 struct bkey_s_c k)
264{
265 struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(k);
266
267 prt_printf(out, "refcount: %llu ", le64_to_cpu(r.v->refcount));
268
269 bch2_bkey_ptrs_to_text(out, c, k);
270}
271
272#if 0
273Currently disabled, needs to be debugged:
274
275bool bch2_reflink_v_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
276{
277 struct bkey_s_reflink_v l = bkey_s_to_reflink_v(_l);
278 struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(_r);
279
280 return l.v->refcount == r.v->refcount && bch2_extent_merge(c, _l, _r);
281}
282#endif
283
284static inline void check_indirect_extent_deleting(struct bkey_s new, unsigned *flags)
285{
286 if ((*flags & BTREE_TRIGGER_INSERT) && !*bkey_refcount(k: new)) {
287 new.k->type = KEY_TYPE_deleted;
288 new.k->size = 0;
289 set_bkey_val_u64s(k: new.k, val_u64s: 0);
290 *flags &= ~BTREE_TRIGGER_INSERT;
291 }
292}
293
294int bch2_trigger_reflink_v(struct btree_trans *trans,
295 enum btree_id btree_id, unsigned level,
296 struct bkey_s_c old, struct bkey_s new,
297 unsigned flags)
298{
299 if ((flags & BTREE_TRIGGER_TRANSACTIONAL) &&
300 (flags & BTREE_TRIGGER_INSERT))
301 check_indirect_extent_deleting(new, flags: &flags);
302
303 return bch2_trigger_extent(trans, btree_id, level, old, new, flags);
304}
305
306/* indirect inline data */
307
308int bch2_indirect_inline_data_invalid(struct bch_fs *c, struct bkey_s_c k,
309 enum bkey_invalid_flags flags,
310 struct printbuf *err)
311{
312 return 0;
313}
314
315void bch2_indirect_inline_data_to_text(struct printbuf *out,
316 struct bch_fs *c, struct bkey_s_c k)
317{
318 struct bkey_s_c_indirect_inline_data d = bkey_s_c_to_indirect_inline_data(k);
319 unsigned datalen = bkey_inline_data_bytes(k: k.k);
320
321 prt_printf(out, "refcount %llu datalen %u: %*phN",
322 le64_to_cpu(d.v->refcount), datalen,
323 min(datalen, 32U), d.v->data);
324}
325
326int bch2_trigger_indirect_inline_data(struct btree_trans *trans,
327 enum btree_id btree_id, unsigned level,
328 struct bkey_s_c old, struct bkey_s new,
329 unsigned flags)
330{
331 check_indirect_extent_deleting(new, flags: &flags);
332
333 return 0;
334}
335
336static int bch2_make_extent_indirect(struct btree_trans *trans,
337 struct btree_iter *extent_iter,
338 struct bkey_i *orig)
339{
340 struct bch_fs *c = trans->c;
341 struct btree_iter reflink_iter = { NULL };
342 struct bkey_s_c k;
343 struct bkey_i *r_v;
344 struct bkey_i_reflink_p *r_p;
345 __le64 *refcount;
346 int ret;
347
348 if (orig->k.type == KEY_TYPE_inline_data)
349 bch2_check_set_feature(c, feat: BCH_FEATURE_reflink_inline_data);
350
351 bch2_trans_iter_init(trans, iter: &reflink_iter, btree_id: BTREE_ID_reflink, POS_MAX,
352 flags: BTREE_ITER_INTENT);
353 k = bch2_btree_iter_peek_prev(&reflink_iter);
354 ret = bkey_err(k);
355 if (ret)
356 goto err;
357
358 r_v = bch2_trans_kmalloc(trans, size: sizeof(__le64) + bkey_bytes(&orig->k));
359 ret = PTR_ERR_OR_ZERO(ptr: r_v);
360 if (ret)
361 goto err;
362
363 bkey_init(k: &r_v->k);
364 r_v->k.type = bkey_type_to_indirect(k: &orig->k);
365 r_v->k.p = reflink_iter.pos;
366 bch2_key_resize(k: &r_v->k, new_size: orig->k.size);
367 r_v->k.version = orig->k.version;
368
369 set_bkey_val_bytes(k: &r_v->k, bytes: sizeof(__le64) + bkey_val_bytes(k: &orig->k));
370
371 refcount = bkey_refcount(k: bkey_i_to_s(k: r_v));
372 *refcount = 0;
373 memcpy(refcount + 1, &orig->v, bkey_val_bytes(&orig->k));
374
375 ret = bch2_trans_update(trans, &reflink_iter, r_v, 0);
376 if (ret)
377 goto err;
378
379 /*
380 * orig is in a bkey_buf which statically allocates 5 64s for the val,
381 * so we know it will be big enough:
382 */
383 orig->k.type = KEY_TYPE_reflink_p;
384 r_p = bkey_i_to_reflink_p(k: orig);
385 set_bkey_val_bytes(k: &r_p->k, bytes: sizeof(r_p->v));
386
387 /* FORTIFY_SOURCE is broken here, and doesn't provide unsafe_memset() */
388#if !defined(__NO_FORTIFY) && defined(__OPTIMIZE__) && defined(CONFIG_FORTIFY_SOURCE)
389 __underlying_memset(&r_p->v, 0, sizeof(r_p->v));
390#else
391 memset(&r_p->v, 0, sizeof(r_p->v));
392#endif
393
394 r_p->v.idx = cpu_to_le64(bkey_start_offset(&r_v->k));
395
396 ret = bch2_trans_update(trans, extent_iter, &r_p->k_i,
397 BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE);
398err:
399 bch2_trans_iter_exit(trans, &reflink_iter);
400
401 return ret;
402}
403
404static struct bkey_s_c get_next_src(struct btree_iter *iter, struct bpos end)
405{
406 struct bkey_s_c k;
407 int ret;
408
409 for_each_btree_key_upto_continue_norestart(*iter, end, 0, k, ret) {
410 if (bkey_extent_is_unwritten(k))
411 continue;
412
413 if (bkey_extent_is_data(k: k.k))
414 return k;
415 }
416
417 if (bkey_ge(l: iter->pos, r: end))
418 bch2_btree_iter_set_pos(iter, new_pos: end);
419 return ret ? bkey_s_c_err(ret) : bkey_s_c_null;
420}
421
422s64 bch2_remap_range(struct bch_fs *c,
423 subvol_inum dst_inum, u64 dst_offset,
424 subvol_inum src_inum, u64 src_offset,
425 u64 remap_sectors,
426 u64 new_i_size, s64 *i_sectors_delta)
427{
428 struct btree_trans *trans;
429 struct btree_iter dst_iter, src_iter;
430 struct bkey_s_c src_k;
431 struct bkey_buf new_dst, new_src;
432 struct bpos dst_start = POS(dst_inum.inum, dst_offset);
433 struct bpos src_start = POS(src_inum.inum, src_offset);
434 struct bpos dst_end = dst_start, src_end = src_start;
435 struct bch_io_opts opts;
436 struct bpos src_want;
437 u64 dst_done = 0;
438 u32 dst_snapshot, src_snapshot;
439 int ret = 0, ret2 = 0;
440
441 if (!bch2_write_ref_tryget(c, ref: BCH_WRITE_REF_reflink))
442 return -BCH_ERR_erofs_no_writes;
443
444 bch2_check_set_feature(c, feat: BCH_FEATURE_reflink);
445
446 dst_end.offset += remap_sectors;
447 src_end.offset += remap_sectors;
448
449 bch2_bkey_buf_init(s: &new_dst);
450 bch2_bkey_buf_init(s: &new_src);
451 trans = bch2_trans_get(c);
452
453 ret = bch2_inum_opts_get(trans, src_inum, &opts);
454 if (ret)
455 goto err;
456
457 bch2_trans_iter_init(trans, iter: &src_iter, btree_id: BTREE_ID_extents, pos: src_start,
458 flags: BTREE_ITER_INTENT);
459 bch2_trans_iter_init(trans, iter: &dst_iter, btree_id: BTREE_ID_extents, pos: dst_start,
460 flags: BTREE_ITER_INTENT);
461
462 while ((ret == 0 ||
463 bch2_err_matches(ret, BCH_ERR_transaction_restart)) &&
464 bkey_lt(l: dst_iter.pos, r: dst_end)) {
465 struct disk_reservation disk_res = { 0 };
466
467 bch2_trans_begin(trans);
468
469 if (fatal_signal_pending(current)) {
470 ret = -EINTR;
471 break;
472 }
473
474 ret = bch2_subvolume_get_snapshot(trans, src_inum.subvol,
475 &src_snapshot);
476 if (ret)
477 continue;
478
479 bch2_btree_iter_set_snapshot(iter: &src_iter, snapshot: src_snapshot);
480
481 ret = bch2_subvolume_get_snapshot(trans, dst_inum.subvol,
482 &dst_snapshot);
483 if (ret)
484 continue;
485
486 bch2_btree_iter_set_snapshot(iter: &dst_iter, snapshot: dst_snapshot);
487
488 if (dst_inum.inum < src_inum.inum) {
489 /* Avoid some lock cycle transaction restarts */
490 ret = bch2_btree_iter_traverse(&dst_iter);
491 if (ret)
492 continue;
493 }
494
495 dst_done = dst_iter.pos.offset - dst_start.offset;
496 src_want = POS(src_start.inode, src_start.offset + dst_done);
497 bch2_btree_iter_set_pos(iter: &src_iter, new_pos: src_want);
498
499 src_k = get_next_src(iter: &src_iter, end: src_end);
500 ret = bkey_err(src_k);
501 if (ret)
502 continue;
503
504 if (bkey_lt(l: src_want, r: src_iter.pos)) {
505 ret = bch2_fpunch_at(trans, &dst_iter, dst_inum,
506 min(dst_end.offset,
507 dst_iter.pos.offset +
508 src_iter.pos.offset - src_want.offset),
509 i_sectors_delta);
510 continue;
511 }
512
513 if (src_k.k->type != KEY_TYPE_reflink_p) {
514 bch2_btree_iter_set_pos_to_extent_start(iter: &src_iter);
515
516 bch2_bkey_buf_reassemble(s: &new_src, c, k: src_k);
517 src_k = bkey_i_to_s_c(k: new_src.k);
518
519 ret = bch2_make_extent_indirect(trans, extent_iter: &src_iter,
520 orig: new_src.k);
521 if (ret)
522 continue;
523
524 BUG_ON(src_k.k->type != KEY_TYPE_reflink_p);
525 }
526
527 if (src_k.k->type == KEY_TYPE_reflink_p) {
528 struct bkey_s_c_reflink_p src_p =
529 bkey_s_c_to_reflink_p(k: src_k);
530 struct bkey_i_reflink_p *dst_p =
531 bkey_reflink_p_init(k: new_dst.k);
532
533 u64 offset = le64_to_cpu(src_p.v->idx) +
534 (src_want.offset -
535 bkey_start_offset(k: src_k.k));
536
537 dst_p->v.idx = cpu_to_le64(offset);
538 } else {
539 BUG();
540 }
541
542 new_dst.k->k.p = dst_iter.pos;
543 bch2_key_resize(k: &new_dst.k->k,
544 min(src_k.k->p.offset - src_want.offset,
545 dst_end.offset - dst_iter.pos.offset));
546
547 ret = bch2_bkey_set_needs_rebalance(c, new_dst.k, &opts) ?:
548 bch2_extent_update(trans, dst_inum, &dst_iter,
549 new_dst.k, &disk_res,
550 new_i_size, i_sectors_delta,
551 true);
552 bch2_disk_reservation_put(c, res: &disk_res);
553 }
554 bch2_trans_iter_exit(trans, &dst_iter);
555 bch2_trans_iter_exit(trans, &src_iter);
556
557 BUG_ON(!ret && !bkey_eq(dst_iter.pos, dst_end));
558 BUG_ON(bkey_gt(dst_iter.pos, dst_end));
559
560 dst_done = dst_iter.pos.offset - dst_start.offset;
561 new_i_size = min(dst_iter.pos.offset << 9, new_i_size);
562
563 do {
564 struct bch_inode_unpacked inode_u;
565 struct btree_iter inode_iter = { NULL };
566
567 bch2_trans_begin(trans);
568
569 ret2 = bch2_inode_peek(trans, &inode_iter, &inode_u,
570 dst_inum, BTREE_ITER_INTENT);
571
572 if (!ret2 &&
573 inode_u.bi_size < new_i_size) {
574 inode_u.bi_size = new_i_size;
575 ret2 = bch2_inode_write(trans, iter: &inode_iter, inode: &inode_u) ?:
576 bch2_trans_commit(trans, NULL, NULL,
577 flags: BCH_TRANS_COMMIT_no_enospc);
578 }
579
580 bch2_trans_iter_exit(trans, &inode_iter);
581 } while (bch2_err_matches(ret2, BCH_ERR_transaction_restart));
582err:
583 bch2_trans_put(trans);
584 bch2_bkey_buf_exit(s: &new_src, c);
585 bch2_bkey_buf_exit(s: &new_dst, c);
586
587 bch2_write_ref_put(c, ref: BCH_WRITE_REF_reflink);
588
589 return dst_done ?: ret ?: ret2;
590}
591

source code of linux/fs/bcachefs/reflink.c