From: Vyacheslav Dubeyko <[email protected]> Subject: [PATCH v2 1/9] nilfs2: add /sys/fs/nilfs/features group
This patch adds code of creation /sys/fs/nilfs group and /sys/fs/nilfs/features group. The features group contains attributes that describe NILFS file system driver features: (1) revision - show current revision of NILFS file system driver. (2) time_format - show/set time format. There are two formats - seconds and human-readable format. You can set preferable time format by command (for example, setting human-readable format): 'echo human-readable > /sys/fs/nilfs/features/time_format' It was reported by Michael L. Semon <[email protected]> that timestamp output in human-readable format should be changed from "2014-4-12 14:5:38" to "2014-04-12 14:05:38". Second version of the patch fixes this issue. Reported-by: Michael L. Semon <[email protected]> Signed-off-by: Vyacheslav Dubeyko <[email protected]> CC: Vyacheslav Dubeyko <[email protected]> CC: Ryusuke Konishi <[email protected]> --- fs/nilfs2/sysfs.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/nilfs2/sysfs.h | 59 ++++++++++++++++++++ 2 files changed, 217 insertions(+) create mode 100644 fs/nilfs2/sysfs.c create mode 100644 fs/nilfs2/sysfs.h diff --git a/fs/nilfs2/sysfs.c b/fs/nilfs2/sysfs.c new file mode 100644 index 0000000..5a36902 --- /dev/null +++ b/fs/nilfs2/sysfs.c @@ -0,0 +1,158 @@ +/* + * sysfs.c - sysfs support implementation. + * + * Copyright (C) 2005-2014 Nippon Telegraph and Telephone Corporation. + * Copyright (C) 2014 HGST, Inc., a Western Digital Company. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Written by Vyacheslav Dubeyko <[email protected]> + */ + +#include <linux/kobject.h> + +#include "nilfs.h" +#include "mdt.h" +#include "sufile.h" +#include "cpfile.h" +#include "sysfs.h" + +/* /sys/fs/nilfs/ */ +static struct kset *nilfs_kset; + +enum { + NILFS_SHOW_TIME_SECONDS = 0, + NILFS_SHOW_HUMAN_READABLE_TIME = 1 +}; + +#define NILFS_SECONDS_STR "seconds" +#define NILFS_HUMAN_READABLE_STR "human-readable" + +static int nilfs_show_time_format = NILFS_SHOW_HUMAN_READABLE_TIME; + +#define NILFS_SHOW_TIME(time_t_val, buf) ({ \ + struct tm res; \ + int count = 0; \ + time_to_tm(time_t_val, 0, &res); \ + res.tm_year += 1900; \ + res.tm_mon += 1; \ + count = scnprintf(buf, PAGE_SIZE, \ + "%ld-%.2d-%.2d %.2d:%.2d:%.2d\n", \ + res.tm_year, res.tm_mon, res.tm_mday, \ + res.tm_hour, res.tm_min, res.tm_sec);\ + count; \ +}) + +/************************************************************************ + * NILFS feature attrs * + ************************************************************************/ + +static ssize_t nilfs_feature_revision_show(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%d.%d\n", + NILFS_CURRENT_REV, NILFS_MINOR_REV); +} + +static ssize_t +nilfs_feature_time_format_show(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%s\n", + (nilfs_show_time_format == NILFS_SHOW_TIME_SECONDS ? + NILFS_SECONDS_STR : NILFS_HUMAN_READABLE_STR)); +} + +static ssize_t +nilfs_feature_time_format_store(struct kobject *kobj, + struct attribute *attr, + const char *buf, size_t count) +{ + size_t secs_len = strlen(NILFS_SECONDS_STR); + size_t hr_len = strlen(NILFS_HUMAN_READABLE_STR); + + if (strncmp(buf, NILFS_SECONDS_STR, secs_len) == 0) + nilfs_show_time_format = NILFS_SHOW_TIME_SECONDS; + else if (strncmp(buf, NILFS_HUMAN_READABLE_STR, hr_len) == 0) + nilfs_show_time_format = NILFS_SHOW_HUMAN_READABLE_TIME; + else { + printk(KERN_ERR "NILFS: unrecognized time format! You should use 'seconds' or 'human-readable' strings only\n"); + return -EOPNOTSUPP; + } + + return count; +} + +static const char features_readme_str[] = + "The features group contains attributes that describe NILFS file\n" + "system driver features.\n\n" + "(1) revision\n\tshow current revision of NILFS file system driver.\n\n" + "(2) time_format\n\tshow/set time format.\n\n" + "\tThere are two formats - seconds and human-readable format.\n" + "\tYou can set preferable time format by command:\n\n" + "\t'echo human-readable > /sys/fs/nilfs/features/time_format'\n\n"; + +static ssize_t nilfs_feature_README_show(struct kobject *kobj, + struct attribute *attr, + char *buf) +{ + return snprintf(buf, PAGE_SIZE, features_readme_str); +} + +NILFS_FEATURE_RO_ATTR(revision); +NILFS_FEATURE_RW_ATTR(time_format); +NILFS_FEATURE_RO_ATTR(README); + +static struct attribute *nilfs_feature_attrs[] = { + NILFS_FEATURE_ATTR_LIST(revision), + NILFS_FEATURE_ATTR_LIST(time_format), + NILFS_FEATURE_ATTR_LIST(README), + NULL, +}; + +static const struct attribute_group nilfs_feature_attr_group = { + .name = "features", + .attrs = nilfs_feature_attrs, +}; + +int __init nilfs_sysfs_init(void) +{ + int err; + + nilfs_kset = kset_create_and_add("nilfs", NULL, fs_kobj); + if (!nilfs_kset) { + err = -ENOMEM; + printk(KERN_ERR "NILFS: unable to create sysfs entry: err %d\n", + err); + goto failed_sysfs_init; + } + + err = sysfs_create_group(&nilfs_kset->kobj, &nilfs_feature_attr_group); + if (unlikely(err)) { + printk(KERN_ERR "NILFS: unable to create feature group: err %d\n", + err); + goto cleanup_sysfs_init; + } + + return 0; + +cleanup_sysfs_init: + kset_unregister(nilfs_kset); + +failed_sysfs_init: + return err; +} + +void nilfs_sysfs_exit(void) +{ + sysfs_remove_group(&nilfs_kset->kobj, &nilfs_feature_attr_group); + kset_unregister(nilfs_kset); +} diff --git a/fs/nilfs2/sysfs.h b/fs/nilfs2/sysfs.h new file mode 100644 index 0000000..b3ba2e4 --- /dev/null +++ b/fs/nilfs2/sysfs.h @@ -0,0 +1,59 @@ +/* + * sysfs.h - sysfs support declarations. + * + * Copyright (C) 2005-2014 Nippon Telegraph and Telephone Corporation. + * Copyright (C) 2014 HGST, Inc., a Western Digital Company. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Written by Vyacheslav Dubeyko <[email protected]> + */ + +#ifndef _NILFS_SYSFS_H +#define _NILFS_SYSFS_H + +#include <linux/sysfs.h> + +#define NILFS_COMMON_ATTR_STRUCT(name) \ +struct nilfs_##name##_attr { \ + struct attribute attr; \ + ssize_t (*show)(struct kobject *, struct attribute *, \ + char *); \ + ssize_t (*store)(struct kobject *, struct attribute *, \ + const char *, size_t); \ +}; + +NILFS_COMMON_ATTR_STRUCT(feature); + +#define NILFS_ATTR(type, name, mode, show, store) \ + static struct nilfs_##type##_attr nilfs_##type##_attr_##name = \ + __ATTR(name, mode, show, store) + +#define NILFS_INFO_ATTR(type, name) \ + NILFS_ATTR(type, name, 0444, NULL, NULL) +#define NILFS_RO_ATTR(type, name) \ + NILFS_ATTR(type, name, 0444, nilfs_##type##_##name##_show, NULL) +#define NILFS_RW_ATTR(type, name) \ + NILFS_ATTR(type, name, 0644, \ + nilfs_##type##_##name##_show, \ + nilfs_##type##_##name##_store) + +#define NILFS_FEATURE_INFO_ATTR(name) \ + NILFS_INFO_ATTR(feature, name) +#define NILFS_FEATURE_RO_ATTR(name) \ + NILFS_RO_ATTR(feature, name) +#define NILFS_FEATURE_RW_ATTR(name) \ + NILFS_RW_ATTR(feature, name) + +#define NILFS_FEATURE_ATTR_LIST(name) \ + (&nilfs_feature_attr_##name.attr) + +#endif /* _NILFS_SYSFS_H */ -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
