1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Feature set bits and string conversion.
4 * Inspired by ext4's features compat/incompat/ro_compat related code.
5 *
6 * Copyright 2020 Coly Li <colyli@suse.de>
7 *
8 */
9#include "bcache_ondisk.h"
10#include "bcache.h"
11#include "features.h"
12
13struct feature {
14	int		compat;
15	unsigned int	mask;
16	const char	*string;
17};
18
19static struct feature feature_list[] = {
20	{BCH_FEATURE_INCOMPAT, BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE,
21		"large_bucket"},
22	{0, 0, NULL },
23};
24
25#define compose_feature_string(type)				\
26({									\
27	struct feature *f;						\
28	bool first = true;						\
29									\
30	for (f = &feature_list[0]; f->compat != 0; f++) {		\
31		if (f->compat != BCH_FEATURE_ ## type)			\
32			continue;					\
33		if (BCH_HAS_ ## type ## _FEATURE(&c->cache->sb, f->mask)) {	\
34			if (first) {					\
35				out += snprintf(out, buf + size - out,	\
36						"[");	\
37			} else {					\
38				out += snprintf(out, buf + size - out,	\
39						" [");			\
40			}						\
41		} else if (!first) {					\
42			out += snprintf(out, buf + size - out, " ");	\
43		}							\
44									\
45		out += snprintf(out, buf + size - out, "%s", f->string);\
46									\
47		if (BCH_HAS_ ## type ## _FEATURE(&c->cache->sb, f->mask))	\
48			out += snprintf(out, buf + size - out, "]");	\
49									\
50		first = false;						\
51	}								\
52	if (!first)							\
53		out += snprintf(out, buf + size - out, "\n");		\
54})
55
56int bch_print_cache_set_feature_compat(struct cache_set *c, char *buf, int size)
57{
58	char *out = buf;
59	compose_feature_string(COMPAT);
60	return out - buf;
61}
62
63int bch_print_cache_set_feature_ro_compat(struct cache_set *c, char *buf, int size)
64{
65	char *out = buf;
66	compose_feature_string(RO_COMPAT);
67	return out - buf;
68}
69
70int bch_print_cache_set_feature_incompat(struct cache_set *c, char *buf, int size)
71{
72	char *out = buf;
73	compose_feature_string(INCOMPAT);
74	return out - buf;
75}
76