summaryrefslogtreecommitdiff
path: root/fs/bcachefs/reflink.c
blob: 6e1bfe9feb59e4abe96e1dc74b30196fa5766f48 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
// SPDX-License-Identifier: GPL-2.0
#include "bcachefs.h"
#include "bkey_buf.h"
#include "btree_update.h"
#include "buckets.h"
#include "extents.h"
#include "inode.h"
#include "io_misc.h"
#include "io_write.h"
#include "rebalance.h"
#include "reflink.h"
#include "subvolume.h"
#include "super-io.h"

#include <linux/sched/signal.h>

static inline unsigned bkey_type_to_indirect(const struct bkey *k)
{
	switch (k->type) {
	case KEY_TYPE_extent:
		return KEY_TYPE_reflink_v;
	case KEY_TYPE_inline_data:
		return KEY_TYPE_indirect_inline_data;
	default:
		return 0;
	}
}

/* reflink pointers */

int bch2_reflink_p_invalid(struct bch_fs *c, struct bkey_s_c k,
			   enum bkey_invalid_flags flags,
			   struct printbuf *err)
{
	struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);

	if (c->sb.version >= bcachefs_metadata_version_reflink_p_fix &&
	    le64_to_cpu(p.v->idx) < le32_to_cpu(p.v->front_pad)) {
		prt_printf(err, "idx < front_pad (%llu < %u)",
		       le64_to_cpu(p.v->idx), le32_to_cpu(p.v->front_pad));
		return -EINVAL;
	}

	return 0;
}

void bch2_reflink_p_to_text(struct printbuf *out, struct bch_fs *c,
			    struct bkey_s_c k)
{
	struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);

	prt_printf(out, "idx %llu front_pad %u back_pad %u",
	       le64_to_cpu(p.v->idx),
	       le32_to_cpu(p.v->front_pad),
	       le32_to_cpu(p.v->back_pad));
}

bool bch2_reflink_p_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
{
	struct bkey_s_reflink_p l = bkey_s_to_reflink_p(_l);
	struct bkey_s_c_reflink_p r = bkey_s_c_to_reflink_p(_r);

	/*
	 * Disabled for now, the triggers code needs to be reworked for merging
	 * of reflink pointers to work:
	 */
	return false;

	if (le64_to_cpu(l.v->idx) + l.k->size != le64_to_cpu(r.v->idx))
		return false;

	bch2_key_resize(l.k, l.k->size + r.k->size);
	return true;
}

/* indirect extents */

int bch2_reflink_v_invalid(struct bch_fs *c, struct bkey_s_c k,
			   enum bkey_invalid_flags flags,
			   struct printbuf *err)
{
	return bch2_bkey_ptrs_invalid(c, k, flags, err);
}

void bch2_reflink_v_to_text(struct printbuf *out, struct bch_fs *c,
			    struct bkey_s_c k)
{
	struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(k);

	prt_printf(out, "refcount: %llu ", le64_to_cpu(r.v->refcount));

	bch2_bkey_ptrs_to_text(out, c, k);
}

#if 0
Currently disabled, needs to be debugged:

bool bch2_reflink_v_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
{
	struct bkey_s_reflink_v   l = bkey_s_to_reflink_v(_l);
	struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(_r);

	return l.v->refcount == r.v->refcount && bch2_extent_merge(c, _l, _r);
}
#endif

static inline void check_indirect_extent_deleting(struct bkey_i *new, unsigned *flags)
{
	if ((*flags & BTREE_TRIGGER_INSERT) && !*bkey_refcount(new)) {
		new->k.type = KEY_TYPE_deleted;
		new->k.size = 0;
		set_bkey_val_u64s(&new->k, 0);;
		*flags &= ~BTREE_TRIGGER_INSERT;
	}
}

int bch2_trans_mark_reflink_v(struct btree_trans *trans,
			      enum btree_id btree_id, unsigned level,
			      struct bkey_s_c old, struct bkey_i *new,
			      unsigned flags)
{
	check_indirect_extent_deleting(new, &flags);

	return bch2_trans_mark_extent(trans, btree_id, level, old, new, flags);
}

/* indirect inline data */

int bch2_indirect_inline_data_invalid(struct bch_fs *c, struct bkey_s_c k,
				      enum bkey_invalid_flags flags,
				      struct printbuf *err)
{
	return 0;
}

void bch2_indirect_inline_data_to_text(struct printbuf *out,
				       struct bch_fs *c, struct bkey_s_c k)
{
	struct bkey_s_c_indirect_inline_data d = bkey_s_c_to_indirect_inline_data(k);
	unsigned datalen = bkey_inline_data_bytes(k.k);

	prt_printf(out, "refcount %llu datalen %u: %*phN",
	       le64_to_cpu(d.v->refcount), datalen,
	       min(datalen, 32U), d.v->data);
}

int bch2_trans_mark_indirect_inline_data(struct btree_trans *trans,
			      enum btree_id btree_id, unsigned level,
			      struct bkey_s_c old, struct bkey_i *new,
			      unsigned flags)
{
	check_indirect_extent_deleting(new, &flags);

	return 0;
}

static int bch2_make_extent_indirect(struct btree_trans *trans,
				     struct btree_iter *extent_iter,
				     struct bkey_i *orig)
{
	struct bch_fs *c = trans->c;
	struct btree_iter reflink_iter = { NULL };
	struct bkey_s_c k;
	struct bkey_i *r_v;
	struct bkey_i_reflink_p *r_p;
	__le64 *refcount;
	int ret;

	if (orig->k.type == KEY_TYPE_inline_data)
		bch2_check_set_feature(c, BCH_FEATURE_reflink_inline_data);

	bch2_trans_iter_init(trans, &reflink_iter, BTREE_ID_reflink, POS_MAX,
			     BTREE_ITER_INTENT);
	k = bch2_btree_iter_peek_prev(&reflink_iter);
	ret = bkey_err(k);
	if (ret)
		goto err;

	r_v = bch2_trans_kmalloc(trans, sizeof(__le64) + bkey_bytes(&orig->k));
	ret = PTR_ERR_OR_ZERO(r_v);
	if (ret)
		goto err;

	bkey_init(&r_v->k);
	r_v->k.type	= bkey_type_to_indirect(&orig->k);
	r_v->k.p	= reflink_iter.pos;
	bch2_key_resize(&r_v->k, orig->k.size);
	r_v->k.version	= orig->k.version;

	set_bkey_val_bytes(&r_v->k, sizeof(__le64) + bkey_val_bytes(&orig->k));

	refcount	= bkey_refcount(r_v);
	*refcount	= 0;
	memcpy(refcount + 1, &orig->v, bkey_val_bytes(&orig->k));

	ret = bch2_trans_update(trans, &reflink_iter, r_v, 0);
	if (ret)
		goto err;

	/*
	 * orig is in a bkey_buf which statically allocates 5 64s for the val,
	 * so we know it will be big enough:
	 */
	orig->k.type = KEY_TYPE_reflink_p;
	r_p = bkey_i_to_reflink_p(orig);
	set_bkey_val_bytes(&r_p->k, sizeof(r_p->v));

	/* FORTIFY_SOURCE is broken here, and doesn't provide unsafe_memset() */
#if !defined(__NO_FORTIFY) && defined(__OPTIMIZE__) && defined(CONFIG_FORTIFY_SOURCE)
	__underlying_memset(&r_p->v, 0, sizeof(r_p->v));
#else
	memset(&r_p->v, 0, sizeof(r_p->v));
#endif

	r_p->v.idx = cpu_to_le64(bkey_start_offset(&r_v->k));

	ret = bch2_trans_update(trans, extent_iter, &r_p->k_i,
				BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE);
err:
	bch2_trans_iter_exit(trans, &reflink_iter);

	return ret;
}

static struct bkey_s_c get_next_src(struct btree_iter *iter, struct bpos end)
{
	struct bkey_s_c k;
	int ret;

	for_each_btree_key_upto_continue_norestart(*iter, end, 0, k, ret) {
		if (bkey_extent_is_unwritten(k))
			continue;

		if (bkey_extent_is_data(k.k))
			return k;
	}

	if (bkey_ge(iter->pos, end))
		bch2_btree_iter_set_pos(iter, end);
	return ret ? bkey_s_c_err(ret) : bkey_s_c_null;
}

s64 bch2_remap_range(struct bch_fs *c,
		     subvol_inum dst_inum, u64 dst_offset,
		     subvol_inum src_inum, u64 src_offset,
		     u64 remap_sectors,
		     u64 new_i_size, s64 *i_sectors_delta)
{
	struct btree_trans *trans;
	struct btree_iter dst_iter, src_iter;
	struct bkey_s_c src_k;
	struct bkey_buf new_dst, new_src;
	struct bpos dst_start = POS(dst_inum.inum, dst_offset);
	struct bpos src_start = POS(src_inum.inum, src_offset);
	struct bpos dst_end = dst_start, src_end = src_start;
	struct bch_io_opts opts;
	struct bpos src_want;
	u64 dst_done = 0;
	u32 dst_snapshot, src_snapshot;
	int ret = 0, ret2 = 0;

	if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_reflink))
		return -BCH_ERR_erofs_no_writes;

	bch2_check_set_feature(c, BCH_FEATURE_reflink);

	dst_end.offset += remap_sectors;
	src_end.offset += remap_sectors;

	bch2_bkey_buf_init(&new_dst);
	bch2_bkey_buf_init(&new_src);
	trans = bch2_trans_get(c);

	ret = bch2_inum_opts_get(trans, src_inum, &opts);
	if (ret)
		goto err;

	bch2_trans_iter_init(trans, &src_iter, BTREE_ID_extents, src_start,
			     BTREE_ITER_INTENT);
	bch2_trans_iter_init(trans, &dst_iter, BTREE_ID_extents, dst_start,
			     BTREE_ITER_INTENT);

	while ((ret == 0 ||
		bch2_err_matches(ret, BCH_ERR_transaction_restart)) &&
	       bkey_lt(dst_iter.pos, dst_end)) {
		struct disk_reservation disk_res = { 0 };

		bch2_trans_begin(trans);

		if (fatal_signal_pending(current)) {
			ret = -EINTR;
			break;
		}

		ret = bch2_subvolume_get_snapshot(trans, src_inum.subvol,
						  &src_snapshot);
		if (ret)
			continue;

		bch2_btree_iter_set_snapshot(&src_iter, src_snapshot);

		ret = bch2_subvolume_get_snapshot(trans, dst_inum.subvol,
						  &dst_snapshot);
		if (ret)
			continue;

		bch2_btree_iter_set_snapshot(&dst_iter, dst_snapshot);

		dst_done = dst_iter.pos.offset - dst_start.offset;
		src_want = POS(src_start.inode, src_start.offset + dst_done);
		bch2_btree_iter_set_pos(&src_iter, src_want);

		src_k = get_next_src(&src_iter, src_end);
		ret = bkey_err(src_k);
		if (ret)
			continue;

		if (bkey_lt(src_want, src_iter.pos)) {
			ret = bch2_fpunch_at(trans, &dst_iter, dst_inum,
					min(dst_end.offset,
					    dst_iter.pos.offset +
					    src_iter.pos.offset - src_want.offset),
					i_sectors_delta);
			continue;
		}

		if (src_k.k->type != KEY_TYPE_reflink_p) {
			bch2_btree_iter_set_pos_to_extent_start(&src_iter);

			bch2_bkey_buf_reassemble(&new_src, c, src_k);
			src_k = bkey_i_to_s_c(new_src.k);

			ret = bch2_make_extent_indirect(trans, &src_iter,
						new_src.k);
			if (ret)
				continue;

			BUG_ON(src_k.k->type != KEY_TYPE_reflink_p);
		}

		if (src_k.k->type == KEY_TYPE_reflink_p) {
			struct bkey_s_c_reflink_p src_p =
				bkey_s_c_to_reflink_p(src_k);
			struct bkey_i_reflink_p *dst_p =
				bkey_reflink_p_init(new_dst.k);

			u64 offset = le64_to_cpu(src_p.v->idx) +
				(src_want.offset -
				 bkey_start_offset(src_k.k));

			dst_p->v.idx = cpu_to_le64(offset);
		} else {
			BUG();
		}

		new_dst.k->k.p = dst_iter.pos;
		bch2_key_resize(&new_dst.k->k,
				min(src_k.k->p.offset - src_want.offset,
				    dst_end.offset - dst_iter.pos.offset));

		ret =   bch2_bkey_set_needs_rebalance(c, new_dst.k,
					opts.background_target,
					opts.background_compression) ?:
			bch2_extent_update(trans, dst_inum, &dst_iter,
					new_dst.k, &disk_res,
					new_i_size, i_sectors_delta,
					true);
		bch2_disk_reservation_put(c, &disk_res);
	}
	bch2_trans_iter_exit(trans, &dst_iter);
	bch2_trans_iter_exit(trans, &src_iter);

	BUG_ON(!ret && !bkey_eq(dst_iter.pos, dst_end));
	BUG_ON(bkey_gt(dst_iter.pos, dst_end));

	dst_done = dst_iter.pos.offset - dst_start.offset;
	new_i_size = min(dst_iter.pos.offset << 9, new_i_size);

	do {
		struct bch_inode_unpacked inode_u;
		struct btree_iter inode_iter = { NULL };

		bch2_trans_begin(trans);

		ret2 = bch2_inode_peek(trans, &inode_iter, &inode_u,
				       dst_inum, BTREE_ITER_INTENT);

		if (!ret2 &&
		    inode_u.bi_size < new_i_size) {
			inode_u.bi_size = new_i_size;
			ret2  = bch2_inode_write(trans, &inode_iter, &inode_u) ?:
				bch2_trans_commit(trans, NULL, NULL,
						  BTREE_INSERT_NOFAIL);
		}

		bch2_trans_iter_exit(trans, &inode_iter);
	} while (bch2_err_matches(ret2, BCH_ERR_transaction_restart));
err:
	bch2_trans_put(trans);
	bch2_bkey_buf_exit(&new_src, c);
	bch2_bkey_buf_exit(&new_dst, c);

	bch2_write_ref_put(c, BCH_WRITE_REF_reflink);

	return dst_done ?: ret ?: ret2;
}