xref: /OK3568_Linux_fs/kernel/drivers/md/bcache/features.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Feature set bits and string conversion.
4*4882a593Smuzhiyun  * Inspired by ext4's features compat/incompat/ro_compat related code.
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Copyright 2020 Coly Li <colyli@suse.de>
7*4882a593Smuzhiyun  *
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun #include <linux/bcache.h>
10*4882a593Smuzhiyun #include "bcache.h"
11*4882a593Smuzhiyun #include "features.h"
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun struct feature {
14*4882a593Smuzhiyun 	int		compat;
15*4882a593Smuzhiyun 	unsigned int	mask;
16*4882a593Smuzhiyun 	const char	*string;
17*4882a593Smuzhiyun };
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun static struct feature feature_list[] = {
20*4882a593Smuzhiyun 	{BCH_FEATURE_INCOMPAT, BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE,
21*4882a593Smuzhiyun 		"large_bucket"},
22*4882a593Smuzhiyun 	{0, 0, 0 },
23*4882a593Smuzhiyun };
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun #define compose_feature_string(type)				\
26*4882a593Smuzhiyun ({									\
27*4882a593Smuzhiyun 	struct feature *f;						\
28*4882a593Smuzhiyun 	bool first = true;						\
29*4882a593Smuzhiyun 									\
30*4882a593Smuzhiyun 	for (f = &feature_list[0]; f->compat != 0; f++) {		\
31*4882a593Smuzhiyun 		if (f->compat != BCH_FEATURE_ ## type)			\
32*4882a593Smuzhiyun 			continue;					\
33*4882a593Smuzhiyun 		if (BCH_HAS_ ## type ## _FEATURE(&c->cache->sb, f->mask)) {	\
34*4882a593Smuzhiyun 			if (first) {					\
35*4882a593Smuzhiyun 				out += snprintf(out, buf + size - out,	\
36*4882a593Smuzhiyun 						"[");	\
37*4882a593Smuzhiyun 			} else {					\
38*4882a593Smuzhiyun 				out += snprintf(out, buf + size - out,	\
39*4882a593Smuzhiyun 						" [");			\
40*4882a593Smuzhiyun 			}						\
41*4882a593Smuzhiyun 		} else if (!first) {					\
42*4882a593Smuzhiyun 			out += snprintf(out, buf + size - out, " ");	\
43*4882a593Smuzhiyun 		}							\
44*4882a593Smuzhiyun 									\
45*4882a593Smuzhiyun 		out += snprintf(out, buf + size - out, "%s", f->string);\
46*4882a593Smuzhiyun 									\
47*4882a593Smuzhiyun 		if (BCH_HAS_ ## type ## _FEATURE(&c->cache->sb, f->mask))	\
48*4882a593Smuzhiyun 			out += snprintf(out, buf + size - out, "]");	\
49*4882a593Smuzhiyun 									\
50*4882a593Smuzhiyun 		first = false;						\
51*4882a593Smuzhiyun 	}								\
52*4882a593Smuzhiyun 	if (!first)							\
53*4882a593Smuzhiyun 		out += snprintf(out, buf + size - out, "\n");		\
54*4882a593Smuzhiyun })
55*4882a593Smuzhiyun 
bch_print_cache_set_feature_compat(struct cache_set * c,char * buf,int size)56*4882a593Smuzhiyun int bch_print_cache_set_feature_compat(struct cache_set *c, char *buf, int size)
57*4882a593Smuzhiyun {
58*4882a593Smuzhiyun 	char *out = buf;
59*4882a593Smuzhiyun 	compose_feature_string(COMPAT);
60*4882a593Smuzhiyun 	return out - buf;
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun 
bch_print_cache_set_feature_ro_compat(struct cache_set * c,char * buf,int size)63*4882a593Smuzhiyun int bch_print_cache_set_feature_ro_compat(struct cache_set *c, char *buf, int size)
64*4882a593Smuzhiyun {
65*4882a593Smuzhiyun 	char *out = buf;
66*4882a593Smuzhiyun 	compose_feature_string(RO_COMPAT);
67*4882a593Smuzhiyun 	return out - buf;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun 
bch_print_cache_set_feature_incompat(struct cache_set * c,char * buf,int size)70*4882a593Smuzhiyun int bch_print_cache_set_feature_incompat(struct cache_set *c, char *buf, int size)
71*4882a593Smuzhiyun {
72*4882a593Smuzhiyun 	char *out = buf;
73*4882a593Smuzhiyun 	compose_feature_string(INCOMPAT);
74*4882a593Smuzhiyun 	return out - buf;
75*4882a593Smuzhiyun }
76