xref: /linux/fs/bcachefs/compress.c (revision f96a974170b749e3a56844e25b31d46a7233b6f6)
1 // SPDX-License-Identifier: GPL-2.0
2 #include "bcachefs.h"
3 #include "checksum.h"
4 #include "compress.h"
5 #include "error.h"
6 #include "extents.h"
7 #include "opts.h"
8 #include "super-io.h"
9 
10 #include <linux/lz4.h>
11 #include <linux/zlib.h>
12 #include <linux/zstd.h>
13 
14 static inline enum bch_compression_opts bch2_compression_type_to_opt(enum bch_compression_type type)
15 {
16 	switch (type) {
17 	case BCH_COMPRESSION_TYPE_none:
18 	case BCH_COMPRESSION_TYPE_incompressible:
19 		return BCH_COMPRESSION_OPT_none;
20 	case BCH_COMPRESSION_TYPE_lz4_old:
21 	case BCH_COMPRESSION_TYPE_lz4:
22 		return BCH_COMPRESSION_OPT_lz4;
23 	case BCH_COMPRESSION_TYPE_gzip:
24 		return BCH_COMPRESSION_OPT_gzip;
25 	case BCH_COMPRESSION_TYPE_zstd:
26 		return BCH_COMPRESSION_OPT_zstd;
27 	default:
28 		BUG();
29 	}
30 }
31 
32 /* Bounce buffer: */
33 struct bbuf {
34 	void		*b;
35 	enum {
36 		BB_NONE,
37 		BB_VMAP,
38 		BB_KMALLOC,
39 		BB_MEMPOOL,
40 	}		type;
41 	int		rw;
42 };
43 
44 static struct bbuf __bounce_alloc(struct bch_fs *c, unsigned size, int rw)
45 {
46 	void *b;
47 
48 	BUG_ON(size > c->opts.encoded_extent_max);
49 
50 	b = kmalloc(size, GFP_NOFS|__GFP_NOWARN);
51 	if (b)
52 		return (struct bbuf) { .b = b, .type = BB_KMALLOC, .rw = rw };
53 
54 	b = mempool_alloc(&c->compression_bounce[rw], GFP_NOFS);
55 	if (b)
56 		return (struct bbuf) { .b = b, .type = BB_MEMPOOL, .rw = rw };
57 
58 	BUG();
59 }
60 
61 static bool bio_phys_contig(struct bio *bio, struct bvec_iter start)
62 {
63 	struct bio_vec bv;
64 	struct bvec_iter iter;
65 	void *expected_start = NULL;
66 
67 	__bio_for_each_bvec(bv, bio, iter, start) {
68 		if (expected_start &&
69 		    expected_start != page_address(bv.bv_page) + bv.bv_offset)
70 			return false;
71 
72 		expected_start = page_address(bv.bv_page) +
73 			bv.bv_offset + bv.bv_len;
74 	}
75 
76 	return true;
77 }
78 
79 static struct bbuf __bio_map_or_bounce(struct bch_fs *c, struct bio *bio,
80 				       struct bvec_iter start, int rw)
81 {
82 	struct bbuf ret;
83 	struct bio_vec bv;
84 	struct bvec_iter iter;
85 	unsigned nr_pages = 0;
86 	struct page *stack_pages[16];
87 	struct page **pages = NULL;
88 	void *data;
89 
90 	BUG_ON(start.bi_size > c->opts.encoded_extent_max);
91 
92 	if (!PageHighMem(bio_iter_page(bio, start)) &&
93 	    bio_phys_contig(bio, start))
94 		return (struct bbuf) {
95 			.b = page_address(bio_iter_page(bio, start)) +
96 				bio_iter_offset(bio, start),
97 			.type = BB_NONE, .rw = rw
98 		};
99 
100 	/* check if we can map the pages contiguously: */
101 	__bio_for_each_segment(bv, bio, iter, start) {
102 		if (iter.bi_size != start.bi_size &&
103 		    bv.bv_offset)
104 			goto bounce;
105 
106 		if (bv.bv_len < iter.bi_size &&
107 		    bv.bv_offset + bv.bv_len < PAGE_SIZE)
108 			goto bounce;
109 
110 		nr_pages++;
111 	}
112 
113 	BUG_ON(DIV_ROUND_UP(start.bi_size, PAGE_SIZE) > nr_pages);
114 
115 	pages = nr_pages > ARRAY_SIZE(stack_pages)
116 		? kmalloc_array(nr_pages, sizeof(struct page *), GFP_NOFS)
117 		: stack_pages;
118 	if (!pages)
119 		goto bounce;
120 
121 	nr_pages = 0;
122 	__bio_for_each_segment(bv, bio, iter, start)
123 		pages[nr_pages++] = bv.bv_page;
124 
125 	data = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
126 	if (pages != stack_pages)
127 		kfree(pages);
128 
129 	if (data)
130 		return (struct bbuf) {
131 			.b = data + bio_iter_offset(bio, start),
132 			.type = BB_VMAP, .rw = rw
133 		};
134 bounce:
135 	ret = __bounce_alloc(c, start.bi_size, rw);
136 
137 	if (rw == READ)
138 		memcpy_from_bio(ret.b, bio, start);
139 
140 	return ret;
141 }
142 
143 static struct bbuf bio_map_or_bounce(struct bch_fs *c, struct bio *bio, int rw)
144 {
145 	return __bio_map_or_bounce(c, bio, bio->bi_iter, rw);
146 }
147 
148 static void bio_unmap_or_unbounce(struct bch_fs *c, struct bbuf buf)
149 {
150 	switch (buf.type) {
151 	case BB_NONE:
152 		break;
153 	case BB_VMAP:
154 		vunmap((void *) ((unsigned long) buf.b & PAGE_MASK));
155 		break;
156 	case BB_KMALLOC:
157 		kfree(buf.b);
158 		break;
159 	case BB_MEMPOOL:
160 		mempool_free(buf.b, &c->compression_bounce[buf.rw]);
161 		break;
162 	}
163 }
164 
165 static inline void zlib_set_workspace(z_stream *strm, void *workspace)
166 {
167 #ifdef __KERNEL__
168 	strm->workspace = workspace;
169 #endif
170 }
171 
172 static int __bio_uncompress(struct bch_fs *c, struct bio *src,
173 			    void *dst_data, struct bch_extent_crc_unpacked crc)
174 {
175 	struct bbuf src_data = { NULL };
176 	size_t src_len = src->bi_iter.bi_size;
177 	size_t dst_len = crc.uncompressed_size << 9;
178 	void *workspace;
179 	int ret;
180 
181 	enum bch_compression_opts opt = bch2_compression_type_to_opt(crc.compression_type);
182 	mempool_t *workspace_pool = &c->compress_workspace[opt];
183 	if (unlikely(!mempool_initialized(workspace_pool))) {
184 		if (fsck_err(c, compression_type_not_marked_in_sb,
185 			     "compression type %s set but not marked in superblock",
186 			     __bch2_compression_types[crc.compression_type]))
187 			ret = bch2_check_set_has_compressed_data(c, opt);
188 		else
189 			ret = -BCH_ERR_compression_workspace_not_initialized;
190 		if (ret)
191 			goto out;
192 	}
193 
194 	src_data = bio_map_or_bounce(c, src, READ);
195 
196 	switch (crc.compression_type) {
197 	case BCH_COMPRESSION_TYPE_lz4_old:
198 	case BCH_COMPRESSION_TYPE_lz4:
199 		ret = LZ4_decompress_safe_partial(src_data.b, dst_data,
200 						  src_len, dst_len, dst_len);
201 		if (ret != dst_len)
202 			goto err;
203 		break;
204 	case BCH_COMPRESSION_TYPE_gzip: {
205 		z_stream strm = {
206 			.next_in	= src_data.b,
207 			.avail_in	= src_len,
208 			.next_out	= dst_data,
209 			.avail_out	= dst_len,
210 		};
211 
212 		workspace = mempool_alloc(workspace_pool, GFP_NOFS);
213 
214 		zlib_set_workspace(&strm, workspace);
215 		zlib_inflateInit2(&strm, -MAX_WBITS);
216 		ret = zlib_inflate(&strm, Z_FINISH);
217 
218 		mempool_free(workspace, workspace_pool);
219 
220 		if (ret != Z_STREAM_END)
221 			goto err;
222 		break;
223 	}
224 	case BCH_COMPRESSION_TYPE_zstd: {
225 		ZSTD_DCtx *ctx;
226 		size_t real_src_len = le32_to_cpup(src_data.b);
227 
228 		if (real_src_len > src_len - 4)
229 			goto err;
230 
231 		workspace = mempool_alloc(workspace_pool, GFP_NOFS);
232 		ctx = zstd_init_dctx(workspace, zstd_dctx_workspace_bound());
233 
234 		ret = zstd_decompress_dctx(ctx,
235 				dst_data,	dst_len,
236 				src_data.b + 4, real_src_len);
237 
238 		mempool_free(workspace, workspace_pool);
239 
240 		if (ret != dst_len)
241 			goto err;
242 		break;
243 	}
244 	default:
245 		BUG();
246 	}
247 	ret = 0;
248 fsck_err:
249 out:
250 	bio_unmap_or_unbounce(c, src_data);
251 	return ret;
252 err:
253 	ret = -EIO;
254 	goto out;
255 }
256 
257 int bch2_bio_uncompress_inplace(struct bch_fs *c, struct bio *bio,
258 				struct bch_extent_crc_unpacked *crc)
259 {
260 	struct bbuf data = { NULL };
261 	size_t dst_len = crc->uncompressed_size << 9;
262 
263 	/* bio must own its pages: */
264 	BUG_ON(!bio->bi_vcnt);
265 	BUG_ON(DIV_ROUND_UP(crc->live_size, PAGE_SECTORS) > bio->bi_max_vecs);
266 
267 	if (crc->uncompressed_size << 9	> c->opts.encoded_extent_max ||
268 	    crc->compressed_size << 9	> c->opts.encoded_extent_max) {
269 		bch_err(c, "error rewriting existing data: extent too big");
270 		return -EIO;
271 	}
272 
273 	data = __bounce_alloc(c, dst_len, WRITE);
274 
275 	if (__bio_uncompress(c, bio, data.b, *crc)) {
276 		if (!c->opts.no_data_io)
277 			bch_err(c, "error rewriting existing data: decompression error");
278 		bio_unmap_or_unbounce(c, data);
279 		return -EIO;
280 	}
281 
282 	/*
283 	 * XXX: don't have a good way to assert that the bio was allocated with
284 	 * enough space, we depend on bch2_move_extent doing the right thing
285 	 */
286 	bio->bi_iter.bi_size = crc->live_size << 9;
287 
288 	memcpy_to_bio(bio, bio->bi_iter, data.b + (crc->offset << 9));
289 
290 	crc->csum_type		= 0;
291 	crc->compression_type	= 0;
292 	crc->compressed_size	= crc->live_size;
293 	crc->uncompressed_size	= crc->live_size;
294 	crc->offset		= 0;
295 	crc->csum		= (struct bch_csum) { 0, 0 };
296 
297 	bio_unmap_or_unbounce(c, data);
298 	return 0;
299 }
300 
301 int bch2_bio_uncompress(struct bch_fs *c, struct bio *src,
302 		       struct bio *dst, struct bvec_iter dst_iter,
303 		       struct bch_extent_crc_unpacked crc)
304 {
305 	struct bbuf dst_data = { NULL };
306 	size_t dst_len = crc.uncompressed_size << 9;
307 	int ret;
308 
309 	if (crc.uncompressed_size << 9	> c->opts.encoded_extent_max ||
310 	    crc.compressed_size << 9	> c->opts.encoded_extent_max)
311 		return -EIO;
312 
313 	dst_data = dst_len == dst_iter.bi_size
314 		? __bio_map_or_bounce(c, dst, dst_iter, WRITE)
315 		: __bounce_alloc(c, dst_len, WRITE);
316 
317 	ret = __bio_uncompress(c, src, dst_data.b, crc);
318 	if (ret)
319 		goto err;
320 
321 	if (dst_data.type != BB_NONE &&
322 	    dst_data.type != BB_VMAP)
323 		memcpy_to_bio(dst, dst_iter, dst_data.b + (crc.offset << 9));
324 err:
325 	bio_unmap_or_unbounce(c, dst_data);
326 	return ret;
327 }
328 
329 static int attempt_compress(struct bch_fs *c,
330 			    void *workspace,
331 			    void *dst, size_t dst_len,
332 			    void *src, size_t src_len,
333 			    struct bch_compression_opt compression)
334 {
335 	enum bch_compression_type compression_type =
336 		__bch2_compression_opt_to_type[compression.type];
337 
338 	switch (compression_type) {
339 	case BCH_COMPRESSION_TYPE_lz4:
340 		if (compression.level < LZ4HC_MIN_CLEVEL) {
341 			int len = src_len;
342 			int ret = LZ4_compress_destSize(
343 					src,		dst,
344 					&len,		dst_len,
345 					workspace);
346 			if (len < src_len)
347 				return -len;
348 
349 			return ret;
350 		} else {
351 			int ret = LZ4_compress_HC(
352 					src,		dst,
353 					src_len,	dst_len,
354 					compression.level,
355 					workspace);
356 
357 			return ret ?: -1;
358 		}
359 	case BCH_COMPRESSION_TYPE_gzip: {
360 		z_stream strm = {
361 			.next_in	= src,
362 			.avail_in	= src_len,
363 			.next_out	= dst,
364 			.avail_out	= dst_len,
365 		};
366 
367 		zlib_set_workspace(&strm, workspace);
368 		zlib_deflateInit2(&strm,
369 				  compression.level
370 				  ? clamp_t(unsigned, compression.level,
371 					    Z_BEST_SPEED, Z_BEST_COMPRESSION)
372 				  : Z_DEFAULT_COMPRESSION,
373 				  Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL,
374 				  Z_DEFAULT_STRATEGY);
375 
376 		if (zlib_deflate(&strm, Z_FINISH) != Z_STREAM_END)
377 			return 0;
378 
379 		if (zlib_deflateEnd(&strm) != Z_OK)
380 			return 0;
381 
382 		return strm.total_out;
383 	}
384 	case BCH_COMPRESSION_TYPE_zstd: {
385 		/*
386 		 * rescale:
387 		 * zstd max compression level is 22, our max level is 15
388 		 */
389 		unsigned level = min((compression.level * 3) / 2, zstd_max_clevel());
390 		ZSTD_parameters params = zstd_get_params(level, c->opts.encoded_extent_max);
391 		ZSTD_CCtx *ctx = zstd_init_cctx(workspace, c->zstd_workspace_size);
392 
393 		/*
394 		 * ZSTD requires that when we decompress we pass in the exact
395 		 * compressed size - rounding it up to the nearest sector
396 		 * doesn't work, so we use the first 4 bytes of the buffer for
397 		 * that.
398 		 *
399 		 * Additionally, the ZSTD code seems to have a bug where it will
400 		 * write just past the end of the buffer - so subtract a fudge
401 		 * factor (7 bytes) from the dst buffer size to account for
402 		 * that.
403 		 */
404 		size_t len = zstd_compress_cctx(ctx,
405 				dst + 4,	dst_len - 4 - 7,
406 				src,		src_len,
407 				&params);
408 		if (zstd_is_error(len))
409 			return 0;
410 
411 		*((__le32 *) dst) = cpu_to_le32(len);
412 		return len + 4;
413 	}
414 	default:
415 		BUG();
416 	}
417 }
418 
419 static unsigned __bio_compress(struct bch_fs *c,
420 			       struct bio *dst, size_t *dst_len,
421 			       struct bio *src, size_t *src_len,
422 			       struct bch_compression_opt compression)
423 {
424 	struct bbuf src_data = { NULL }, dst_data = { NULL };
425 	void *workspace;
426 	enum bch_compression_type compression_type =
427 		__bch2_compression_opt_to_type[compression.type];
428 	unsigned pad;
429 	int ret = 0;
430 
431 	/* bch2_compression_decode catches unknown compression types: */
432 	BUG_ON(compression.type >= BCH_COMPRESSION_OPT_NR);
433 
434 	mempool_t *workspace_pool = &c->compress_workspace[compression.type];
435 	if (unlikely(!mempool_initialized(workspace_pool))) {
436 		if (fsck_err(c, compression_opt_not_marked_in_sb,
437 			     "compression opt %s set but not marked in superblock",
438 			     bch2_compression_opts[compression.type])) {
439 			ret = bch2_check_set_has_compressed_data(c, compression.type);
440 			if (ret) /* memory allocation failure, don't compress */
441 				return 0;
442 		} else {
443 			return 0;
444 		}
445 	}
446 
447 	/* If it's only one block, don't bother trying to compress: */
448 	if (src->bi_iter.bi_size <= c->opts.block_size)
449 		return BCH_COMPRESSION_TYPE_incompressible;
450 
451 	dst_data = bio_map_or_bounce(c, dst, WRITE);
452 	src_data = bio_map_or_bounce(c, src, READ);
453 
454 	workspace = mempool_alloc(workspace_pool, GFP_NOFS);
455 
456 	*src_len = src->bi_iter.bi_size;
457 	*dst_len = dst->bi_iter.bi_size;
458 
459 	/*
460 	 * XXX: this algorithm sucks when the compression code doesn't tell us
461 	 * how much would fit, like LZ4 does:
462 	 */
463 	while (1) {
464 		if (*src_len <= block_bytes(c)) {
465 			ret = -1;
466 			break;
467 		}
468 
469 		ret = attempt_compress(c, workspace,
470 				       dst_data.b,	*dst_len,
471 				       src_data.b,	*src_len,
472 				       compression);
473 		if (ret > 0) {
474 			*dst_len = ret;
475 			ret = 0;
476 			break;
477 		}
478 
479 		/* Didn't fit: should we retry with a smaller amount?  */
480 		if (*src_len <= *dst_len) {
481 			ret = -1;
482 			break;
483 		}
484 
485 		/*
486 		 * If ret is negative, it's a hint as to how much data would fit
487 		 */
488 		BUG_ON(-ret >= *src_len);
489 
490 		if (ret < 0)
491 			*src_len = -ret;
492 		else
493 			*src_len -= (*src_len - *dst_len) / 2;
494 		*src_len = round_down(*src_len, block_bytes(c));
495 	}
496 
497 	mempool_free(workspace, workspace_pool);
498 
499 	if (ret)
500 		goto err;
501 
502 	/* Didn't get smaller: */
503 	if (round_up(*dst_len, block_bytes(c)) >= *src_len)
504 		goto err;
505 
506 	pad = round_up(*dst_len, block_bytes(c)) - *dst_len;
507 
508 	memset(dst_data.b + *dst_len, 0, pad);
509 	*dst_len += pad;
510 
511 	if (dst_data.type != BB_NONE &&
512 	    dst_data.type != BB_VMAP)
513 		memcpy_to_bio(dst, dst->bi_iter, dst_data.b);
514 
515 	BUG_ON(!*dst_len || *dst_len > dst->bi_iter.bi_size);
516 	BUG_ON(!*src_len || *src_len > src->bi_iter.bi_size);
517 	BUG_ON(*dst_len & (block_bytes(c) - 1));
518 	BUG_ON(*src_len & (block_bytes(c) - 1));
519 	ret = compression_type;
520 out:
521 	bio_unmap_or_unbounce(c, src_data);
522 	bio_unmap_or_unbounce(c, dst_data);
523 	return ret;
524 err:
525 	ret = BCH_COMPRESSION_TYPE_incompressible;
526 	goto out;
527 fsck_err:
528 	ret = 0;
529 	goto out;
530 }
531 
532 unsigned bch2_bio_compress(struct bch_fs *c,
533 			   struct bio *dst, size_t *dst_len,
534 			   struct bio *src, size_t *src_len,
535 			   unsigned compression_opt)
536 {
537 	unsigned orig_dst = dst->bi_iter.bi_size;
538 	unsigned orig_src = src->bi_iter.bi_size;
539 	unsigned compression_type;
540 
541 	/* Don't consume more than BCH_ENCODED_EXTENT_MAX from @src: */
542 	src->bi_iter.bi_size = min_t(unsigned, src->bi_iter.bi_size,
543 				     c->opts.encoded_extent_max);
544 	/* Don't generate a bigger output than input: */
545 	dst->bi_iter.bi_size = min(dst->bi_iter.bi_size, src->bi_iter.bi_size);
546 
547 	compression_type =
548 		__bio_compress(c, dst, dst_len, src, src_len,
549 			       bch2_compression_decode(compression_opt));
550 
551 	dst->bi_iter.bi_size = orig_dst;
552 	src->bi_iter.bi_size = orig_src;
553 	return compression_type;
554 }
555 
556 static int __bch2_fs_compress_init(struct bch_fs *, u64);
557 
558 #define BCH_FEATURE_none	0
559 
560 static const unsigned bch2_compression_opt_to_feature[] = {
561 #define x(t, n) [BCH_COMPRESSION_OPT_##t] = BCH_FEATURE_##t,
562 	BCH_COMPRESSION_OPTS()
563 #undef x
564 };
565 
566 #undef BCH_FEATURE_none
567 
568 static int __bch2_check_set_has_compressed_data(struct bch_fs *c, u64 f)
569 {
570 	int ret = 0;
571 
572 	if ((c->sb.features & f) == f)
573 		return 0;
574 
575 	mutex_lock(&c->sb_lock);
576 
577 	if ((c->sb.features & f) == f) {
578 		mutex_unlock(&c->sb_lock);
579 		return 0;
580 	}
581 
582 	ret = __bch2_fs_compress_init(c, c->sb.features|f);
583 	if (ret) {
584 		mutex_unlock(&c->sb_lock);
585 		return ret;
586 	}
587 
588 	c->disk_sb.sb->features[0] |= cpu_to_le64(f);
589 	bch2_write_super(c);
590 	mutex_unlock(&c->sb_lock);
591 
592 	return 0;
593 }
594 
595 int bch2_check_set_has_compressed_data(struct bch_fs *c,
596 				       unsigned compression_opt)
597 {
598 	unsigned compression_type = bch2_compression_decode(compression_opt).type;
599 
600 	BUG_ON(compression_type >= ARRAY_SIZE(bch2_compression_opt_to_feature));
601 
602 	return compression_type
603 		? __bch2_check_set_has_compressed_data(c,
604 				1ULL << bch2_compression_opt_to_feature[compression_type])
605 		: 0;
606 }
607 
608 void bch2_fs_compress_exit(struct bch_fs *c)
609 {
610 	unsigned i;
611 
612 	for (i = 0; i < ARRAY_SIZE(c->compress_workspace); i++)
613 		mempool_exit(&c->compress_workspace[i]);
614 	mempool_exit(&c->compression_bounce[WRITE]);
615 	mempool_exit(&c->compression_bounce[READ]);
616 }
617 
618 static int __bch2_fs_compress_init(struct bch_fs *c, u64 features)
619 {
620 	ZSTD_parameters params = zstd_get_params(zstd_max_clevel(),
621 						 c->opts.encoded_extent_max);
622 
623 	c->zstd_workspace_size = zstd_cctx_workspace_bound(&params.cParams);
624 
625 	struct {
626 		unsigned			feature;
627 		enum bch_compression_opts	type;
628 		size_t				compress_workspace;
629 	} compression_types[] = {
630 		{ BCH_FEATURE_lz4, BCH_COMPRESSION_OPT_lz4,
631 			max_t(size_t, LZ4_MEM_COMPRESS, LZ4HC_MEM_COMPRESS) },
632 		{ BCH_FEATURE_gzip, BCH_COMPRESSION_OPT_gzip,
633 			max(zlib_deflate_workspacesize(MAX_WBITS, DEF_MEM_LEVEL),
634 			    zlib_inflate_workspacesize()) },
635 		{ BCH_FEATURE_zstd, BCH_COMPRESSION_OPT_zstd,
636 			max(c->zstd_workspace_size,
637 			    zstd_dctx_workspace_bound()) },
638 	}, *i;
639 	bool have_compressed = false;
640 
641 	for (i = compression_types;
642 	     i < compression_types + ARRAY_SIZE(compression_types);
643 	     i++)
644 		have_compressed |= (features & (1 << i->feature)) != 0;
645 
646 	if (!have_compressed)
647 		return 0;
648 
649 	if (!mempool_initialized(&c->compression_bounce[READ]) &&
650 	    mempool_init_kvmalloc_pool(&c->compression_bounce[READ],
651 				       1, c->opts.encoded_extent_max))
652 		return -BCH_ERR_ENOMEM_compression_bounce_read_init;
653 
654 	if (!mempool_initialized(&c->compression_bounce[WRITE]) &&
655 	    mempool_init_kvmalloc_pool(&c->compression_bounce[WRITE],
656 				       1, c->opts.encoded_extent_max))
657 		return -BCH_ERR_ENOMEM_compression_bounce_write_init;
658 
659 	for (i = compression_types;
660 	     i < compression_types + ARRAY_SIZE(compression_types);
661 	     i++) {
662 		if (!(features & (1 << i->feature)))
663 			continue;
664 
665 		if (mempool_initialized(&c->compress_workspace[i->type]))
666 			continue;
667 
668 		if (mempool_init_kvmalloc_pool(
669 				&c->compress_workspace[i->type],
670 				1, i->compress_workspace))
671 			return -BCH_ERR_ENOMEM_compression_workspace_init;
672 	}
673 
674 	return 0;
675 }
676 
677 static u64 compression_opt_to_feature(unsigned v)
678 {
679 	unsigned type = bch2_compression_decode(v).type;
680 
681 	return BIT_ULL(bch2_compression_opt_to_feature[type]);
682 }
683 
684 int bch2_fs_compress_init(struct bch_fs *c)
685 {
686 	u64 f = c->sb.features;
687 
688 	f |= compression_opt_to_feature(c->opts.compression);
689 	f |= compression_opt_to_feature(c->opts.background_compression);
690 
691 	return __bch2_fs_compress_init(c, f);
692 }
693 
694 int bch2_opt_compression_parse(struct bch_fs *c, const char *_val, u64 *res,
695 			       struct printbuf *err)
696 {
697 	char *val = kstrdup(_val, GFP_KERNEL);
698 	char *p = val, *type_str, *level_str;
699 	struct bch_compression_opt opt = { 0 };
700 	int ret;
701 
702 	if (!val)
703 		return -ENOMEM;
704 
705 	type_str = strsep(&p, ":");
706 	level_str = p;
707 
708 	ret = match_string(bch2_compression_opts, -1, type_str);
709 	if (ret < 0 && err)
710 		prt_str(err, "invalid compression type");
711 	if (ret < 0)
712 		goto err;
713 
714 	opt.type = ret;
715 
716 	if (level_str) {
717 		unsigned level;
718 
719 		ret = kstrtouint(level_str, 10, &level);
720 		if (!ret && !opt.type && level)
721 			ret = -EINVAL;
722 		if (!ret && level > 15)
723 			ret = -EINVAL;
724 		if (ret < 0 && err)
725 			prt_str(err, "invalid compression level");
726 		if (ret < 0)
727 			goto err;
728 
729 		opt.level = level;
730 	}
731 
732 	*res = bch2_compression_encode(opt);
733 err:
734 	kfree(val);
735 	return ret;
736 }
737 
738 void bch2_compression_opt_to_text(struct printbuf *out, u64 v)
739 {
740 	struct bch_compression_opt opt = bch2_compression_decode(v);
741 
742 	if (opt.type < BCH_COMPRESSION_OPT_NR)
743 		prt_str(out, bch2_compression_opts[opt.type]);
744 	else
745 		prt_printf(out, "(unknown compression opt %u)", opt.type);
746 	if (opt.level)
747 		prt_printf(out, ":%u", opt.level);
748 }
749 
750 void bch2_opt_compression_to_text(struct printbuf *out,
751 				  struct bch_fs *c,
752 				  struct bch_sb *sb,
753 				  u64 v)
754 {
755 	return bch2_compression_opt_to_text(out, v);
756 }
757 
758 int bch2_opt_compression_validate(u64 v, struct printbuf *err)
759 {
760 	if (!bch2_compression_opt_valid(v)) {
761 		prt_printf(err, "invalid compression opt %llu", v);
762 		return -BCH_ERR_invalid_sb_opt_compression;
763 	}
764 
765 	return 0;
766 }
767