bcache: A block layer cache
Does writethrough and writeback caching, handles unclean shutdown, and
has a bunch of other nifty features motivated by real world usage.
See the wiki at http://bcache.evilpiepirate.org for more.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
diff --git a/drivers/md/bcache/sysfs.h b/drivers/md/bcache/sysfs.h
new file mode 100644
index 0000000..34e4ba1
--- /dev/null
+++ b/drivers/md/bcache/sysfs.h
@@ -0,0 +1,110 @@
+#ifndef _BCACHE_SYSFS_H_
+#define _BCACHE_SYSFS_H_
+
+#define KTYPE(type) \
+struct kobj_type type ## _ktype = { \
+ .release = type ## _release, \
+ .sysfs_ops = &((const struct sysfs_ops) { \
+ .show = type ## _show, \
+ .store = type ## _store \
+ }), \
+ .default_attrs = type ## _files \
+}
+
+#define SHOW(fn) \
+static ssize_t fn ## _show(struct kobject *kobj, struct attribute *attr,\
+ char *buf) \
+
+#define STORE(fn) \
+static ssize_t fn ## _store(struct kobject *kobj, struct attribute *attr,\
+ const char *buf, size_t size) \
+
+#define SHOW_LOCKED(fn) \
+SHOW(fn) \
+{ \
+ ssize_t ret; \
+ mutex_lock(&bch_register_lock); \
+ ret = __ ## fn ## _show(kobj, attr, buf); \
+ mutex_unlock(&bch_register_lock); \
+ return ret; \
+}
+
+#define STORE_LOCKED(fn) \
+STORE(fn) \
+{ \
+ ssize_t ret; \
+ mutex_lock(&bch_register_lock); \
+ ret = __ ## fn ## _store(kobj, attr, buf, size); \
+ mutex_unlock(&bch_register_lock); \
+ return ret; \
+}
+
+#define __sysfs_attribute(_name, _mode) \
+ static struct attribute sysfs_##_name = \
+ { .name = #_name, .mode = _mode }
+
+#define write_attribute(n) __sysfs_attribute(n, S_IWUSR)
+#define read_attribute(n) __sysfs_attribute(n, S_IRUGO)
+#define rw_attribute(n) __sysfs_attribute(n, S_IRUGO|S_IWUSR)
+
+#define sysfs_printf(file, fmt, ...) \
+do { \
+ if (attr == &sysfs_ ## file) \
+ return snprintf(buf, PAGE_SIZE, fmt "\n", __VA_ARGS__); \
+} while (0)
+
+#define sysfs_print(file, var) \
+do { \
+ if (attr == &sysfs_ ## file) \
+ return snprint(buf, PAGE_SIZE, var); \
+} while (0)
+
+#define sysfs_hprint(file, val) \
+do { \
+ if (attr == &sysfs_ ## file) { \
+ ssize_t ret = hprint(buf, val); \
+ strcat(buf, "\n"); \
+ return ret + 1; \
+ } \
+} while (0)
+
+#define var_printf(_var, fmt) sysfs_printf(_var, fmt, var(_var))
+#define var_print(_var) sysfs_print(_var, var(_var))
+#define var_hprint(_var) sysfs_hprint(_var, var(_var))
+
+#define sysfs_strtoul(file, var) \
+do { \
+ if (attr == &sysfs_ ## file) \
+ return strtoul_safe(buf, var) ?: (ssize_t) size; \
+} while (0)
+
+#define sysfs_strtoul_clamp(file, var, min, max) \
+do { \
+ if (attr == &sysfs_ ## file) \
+ return strtoul_safe_clamp(buf, var, min, max) \
+ ?: (ssize_t) size; \
+} while (0)
+
+#define strtoul_or_return(cp) \
+({ \
+ unsigned long _v; \
+ int _r = kstrtoul(cp, 10, &_v); \
+ if (_r) \
+ return _r; \
+ _v; \
+})
+
+#define strtoi_h_or_return(cp, v) \
+do { \
+ int _r = strtoi_h(cp, &v); \
+ if (_r) \
+ return _r; \
+} while (0)
+
+#define sysfs_hatoi(file, var) \
+do { \
+ if (attr == &sysfs_ ## file) \
+ return strtoi_h(buf, &var) ?: (ssize_t) size; \
+} while (0)
+
+#endif /* _BCACHE_SYSFS_H_ */