bcache in userspace; userspace fsck

1 files changed, 179 insertions, 0 deletions

diff --git a/libbcache/opts.c b/libbcache/opts.c
new file mode 100644
index 0000000..249dd5d
--- /dev/null
+++ b/libbcache/opts.c
@@ -0,0 +1,179 @@
+
+#include <linux/kernel.h>
+
+#include "opts.h"
+#include "util.h"
+
+const char * const bch_bool_opt[] = {
+	"0",
+	"1",
+	NULL
+};
+
+const char * const bch_uint_opt[] = {
+	NULL
+};
+
+const char * const bch_error_actions[] = {
+	"continue",
+	"remount-ro",
+	"panic",
+	NULL
+};
+
+const char * const bch_csum_types[] = {
+	"none",
+	"crc32c",
+	"crc64",
+	NULL
+};
+
+const char * const bch_compression_types[] = {
+	"none",
+	"lz4",
+	"gzip",
+	NULL
+};
+
+const char * const bch_str_hash_types[] = {
+	"crc32c",
+	"crc64",
+	"siphash",
+	"sha1",
+	NULL
+};
+
+enum bch_opts {
+#define CACHE_SET_OPT(_name, _choices, _min, _max, _sb_opt, _perm)	\
+	Opt_##_name,
+
+	CACHE_SET_VISIBLE_OPTS()
+#undef CACHE_SET_OPT
+
+	Opt_bad_opt,
+};
+
+struct bch_option {
+	const char		*name;
+	const char * const	*opts;
+	unsigned long		min, max;
+};
+
+struct bch_opt_result {
+	enum bch_opts		opt;
+	unsigned		val;
+};
+
+static int parse_bool_opt(const struct bch_option *opt, const char *s)
+{
+	if (!strcmp(opt->name, s))
+		return true;
+
+	if (!strncmp("no", s, 2) && !strcmp(opt->name, s + 2))
+		return false;
+
+	return -1;
+}
+
+static int parse_uint_opt(const struct bch_option *opt, const char *s)
+{
+	unsigned long v;
+	int ret;
+
+	if (strncmp(opt->name, s, strlen(opt->name)))
+		return -1;
+
+	s += strlen(opt->name);
+
+	if (*s != '=')
+		return -1;
+
+	s++;
+
+	ret = kstrtoul(s, 10, &v);
+	if (ret)
+		return ret;
+
+	if (v < opt->min || v >= opt->max)
+		return -ERANGE;
+
+	return 0;
+}
+
+static int parse_string_opt(const struct bch_option *opt, const char *s)
+{
+	if (strncmp(opt->name, s, strlen(opt->name)))
+		return -1;
+
+	s += strlen(opt->name);
+
+	if (*s != '=')
+		return -1;
+
+	s++;
+
+	return bch_read_string_list(s, opt->opts);
+}
+
+static struct bch_opt_result parse_one_opt(const char *opt)
+{
+	static const struct bch_option opt_table[] = {
+#define CACHE_SET_OPT(_name, _choices, _min, _max, _sb_opt, _perm)	\
+		[Opt_##_name] = {					\
+			.name = #_name,					\
+			.opts = _choices,				\
+			.min = _min,					\
+			.max = _max,					\
+		},
+		CACHE_SET_VISIBLE_OPTS()
+#undef CACHE_SET_OPT
+	}, *i;
+
+	for (i = opt_table;
+	     i < opt_table + ARRAY_SIZE(opt_table);
+	     i++) {
+		int res = i->opts == bch_bool_opt ? parse_bool_opt(i, opt)
+			: i->opts == bch_uint_opt ? parse_uint_opt(i, opt)
+			: parse_string_opt(i, opt);
+
+		if (res >= 0)
+			return (struct bch_opt_result) {
+				i - opt_table, res
+			};
+	}
+
+	return (struct bch_opt_result) { Opt_bad_opt };
+}
+
+int bch_parse_options(struct cache_set_opts *opts, int flags, char *options)
+{
+	char *p;
+
+	*opts = cache_set_opts_empty();
+
+	opts->read_only = (flags & MS_RDONLY) != 0;
+
+	if (!options)
+		return 0;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		struct bch_opt_result res = parse_one_opt(p);
+
+		switch (res.opt) {
+#define CACHE_SET_OPT(_name, _choices, _min, _max, _sb_opt, _perm)	\
+		case Opt_##_name:					\
+			opts->_name = res.val;				\
+			break;
+
+		CACHE_SET_VISIBLE_OPTS()
+#undef CACHE_SET_OPT
+
+		case Opt_bad_opt:
+			return -EINVAL;
+		default:
+			BUG();
+		}
+	}
+
+	return 0;
+}