From caa05d49dfd7fe04820ba8b7e424343d5426a7f3 Mon Sep 17 00:00:00 2001 From: Vyacheslav Dubeyko Date: Fri, 8 Aug 2014 14:20:42 -0700 Subject: [PATCH] nilfs2: add /sys/fs/nilfs2//superblock group This patch adds creation of /sys/fs/nilfs2//superblock group. The superblock group contains attributes that describe superblock's details: (1) sb_write_time - show previous write time of super block in human-readable format. (2) sb_write_time_secs - show previous write time of super block in seconds. (3) sb_write_count - show write count of super block. (4) sb_update_frequency - show/set interval of periodical update of superblock (in seconds). You can set preferable frequency of superblock update by command: echo > /sys/fs/nilfs2//superblock/sb_update_frequency Signed-off-by: Vyacheslav Dubeyko Cc: Vyacheslav Dubeyko Cc: Ryusuke Konishi Cc: Michael L. Semon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/ABI/testing/sysfs-fs-nilfs2 | 33 +++++ fs/nilfs2/sysfs.c | 218 +++++++++++++++++++++++++++++- fs/nilfs2/sysfs.h | 19 +++ fs/nilfs2/the_nilfs.c | 1 + fs/nilfs2/the_nilfs.h | 8 +- 5 files changed, 277 insertions(+), 2 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-fs-nilfs2 b/Documentation/ABI/testing/sysfs-fs-nilfs2 index 0a521d0..e9b4c61 100644 --- a/Documentation/ABI/testing/sysfs-fs-nilfs2 +++ b/Documentation/ABI/testing/sysfs-fs-nilfs2 @@ -56,3 +56,36 @@ Date: April 2014 Contact: "Vyacheslav Dubeyko" Description: Describe attributes of /sys/fs/nilfs2/ group. + +What: /sys/fs/nilfs2//superblock/sb_write_time +Date: April 2014 +Contact: "Vyacheslav Dubeyko" +Description: + Show last write time of super block in human-readable + format. + +What: /sys/fs/nilfs2//superblock/sb_write_time_secs +Date: April 2014 +Contact: "Vyacheslav Dubeyko" +Description: + Show last write time of super block in seconds. + +What: /sys/fs/nilfs2//superblock/sb_write_count +Date: April 2014 +Contact: "Vyacheslav Dubeyko" +Description: + Show current write count of super block. + +What: /sys/fs/nilfs2//superblock/sb_update_frequency +Date: April 2014 +Contact: "Vyacheslav Dubeyko" +Description: + Show/Set interval of periodical update of superblock + (in seconds). + +What: /sys/fs/nilfs2//superblock/README +Date: April 2014 +Contact: "Vyacheslav Dubeyko" +Description: + Describe attributes of /sys/fs/nilfs2//superblock + group. diff --git a/fs/nilfs2/sysfs.c b/fs/nilfs2/sysfs.c index 780d0f5..239f239 100644 --- a/fs/nilfs2/sysfs.c +++ b/fs/nilfs2/sysfs.c @@ -41,6 +41,202 @@ static struct kset *nilfs_kset; count; \ }) +#define NILFS_DEV_INT_GROUP_OPS(name, parent_name) \ +static ssize_t nilfs_##name##_attr_show(struct kobject *kobj, \ + struct attribute *attr, char *buf) \ +{ \ + struct the_nilfs *nilfs = container_of(kobj->parent, \ + struct the_nilfs, \ + ns_##parent_name##_kobj); \ + struct nilfs_##name##_attr *a = container_of(attr, \ + struct nilfs_##name##_attr, \ + attr); \ + return a->show ? a->show(a, nilfs, buf) : 0; \ +} \ +static ssize_t nilfs_##name##_attr_store(struct kobject *kobj, \ + struct attribute *attr, \ + const char *buf, size_t len) \ +{ \ + struct the_nilfs *nilfs = container_of(kobj->parent, \ + struct the_nilfs, \ + ns_##parent_name##_kobj); \ + struct nilfs_##name##_attr *a = container_of(attr, \ + struct nilfs_##name##_attr, \ + attr); \ + return a->store ? a->store(a, nilfs, buf, len) : 0; \ +} \ +static const struct sysfs_ops nilfs_##name##_attr_ops = { \ + .show = nilfs_##name##_attr_show, \ + .store = nilfs_##name##_attr_store, \ +}; + +#define NILFS_DEV_INT_GROUP_TYPE(name, parent_name) \ +static void nilfs_##name##_attr_release(struct kobject *kobj) \ +{ \ + struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \ + struct the_nilfs *nilfs = container_of(kobj->parent, \ + struct the_nilfs, \ + ns_##parent_name##_kobj); \ + subgroups = nilfs->ns_##parent_name##_subgroups; \ + complete(&subgroups->sg_##name##_kobj_unregister); \ +} \ +static struct kobj_type nilfs_##name##_ktype = { \ + .default_attrs = nilfs_##name##_attrs, \ + .sysfs_ops = &nilfs_##name##_attr_ops, \ + .release = nilfs_##name##_attr_release, \ +}; + +#define NILFS_DEV_INT_GROUP_FNS(name, parent_name) \ +int nilfs_sysfs_create_##name##_group(struct the_nilfs *nilfs) \ +{ \ + struct kobject *parent; \ + struct kobject *kobj; \ + struct completion *kobj_unregister; \ + struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \ + int err; \ + subgroups = nilfs->ns_##parent_name##_subgroups; \ + kobj = &subgroups->sg_##name##_kobj; \ + kobj_unregister = &subgroups->sg_##name##_kobj_unregister; \ + parent = &nilfs->ns_##parent_name##_kobj; \ + kobj->kset = nilfs_kset; \ + init_completion(kobj_unregister); \ + err = kobject_init_and_add(kobj, &nilfs_##name##_ktype, parent, \ + #name); \ + if (err) \ + return err; \ + return 0; \ +} \ +void nilfs_sysfs_delete_##name##_group(struct the_nilfs *nilfs) \ +{ \ + kobject_del(&nilfs->ns_##parent_name##_subgroups->sg_##name##_kobj); \ +} + +/************************************************************************ + * NILFS superblock attrs * + ************************************************************************/ + +static ssize_t +nilfs_superblock_sb_write_time_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + time_t sbwtime; + + down_read(&nilfs->ns_sem); + sbwtime = nilfs->ns_sbwtime; + up_read(&nilfs->ns_sem); + + return NILFS_SHOW_TIME(sbwtime, buf); +} + +static ssize_t +nilfs_superblock_sb_write_time_secs_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + time_t sbwtime; + + down_read(&nilfs->ns_sem); + sbwtime = nilfs->ns_sbwtime; + up_read(&nilfs->ns_sem); + + return snprintf(buf, PAGE_SIZE, "%llu\n", (unsigned long long)sbwtime); +} + +static ssize_t +nilfs_superblock_sb_write_count_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + unsigned sbwcount; + + down_read(&nilfs->ns_sem); + sbwcount = nilfs->ns_sbwcount; + up_read(&nilfs->ns_sem); + + return snprintf(buf, PAGE_SIZE, "%u\n", sbwcount); +} + +static ssize_t +nilfs_superblock_sb_update_frequency_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + unsigned sb_update_freq; + + down_read(&nilfs->ns_sem); + sb_update_freq = nilfs->ns_sb_update_freq; + up_read(&nilfs->ns_sem); + + return snprintf(buf, PAGE_SIZE, "%u\n", sb_update_freq); +} + +static ssize_t +nilfs_superblock_sb_update_frequency_store(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + const char *buf, size_t count) +{ + unsigned val; + int err; + + err = kstrtouint(skip_spaces(buf), 0, &val); + if (err) { + printk(KERN_ERR "NILFS: unable to convert string: err=%d\n", + err); + return err; + } + + if (val < NILFS_SB_FREQ) { + val = NILFS_SB_FREQ; + printk(KERN_WARNING "NILFS: superblock update frequency cannot be lesser than 10 seconds\n"); + } + + down_write(&nilfs->ns_sem); + nilfs->ns_sb_update_freq = val; + up_write(&nilfs->ns_sem); + + return count; +} + +static const char sb_readme_str[] = + "The superblock group contains attributes that describe\n" + "superblock's details.\n\n" + "(1) sb_write_time\n\tshow previous write time of super block " + "in human-readable format.\n\n" + "(2) sb_write_time_secs\n\tshow previous write time of super block " + "in seconds.\n\n" + "(3) sb_write_count\n\tshow write count of super block.\n\n" + "(4) sb_update_frequency\n" + "\tshow/set interval of periodical update of superblock (in seconds).\n\n" + "\tYou can set preferable frequency of superblock update by command:\n\n" + "\t'echo > /sys/fs///superblock/sb_update_frequency'\n"; + +static ssize_t +nilfs_superblock_README_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, char *buf) +{ + return snprintf(buf, PAGE_SIZE, sb_readme_str); +} + +NILFS_SUPERBLOCK_RO_ATTR(sb_write_time); +NILFS_SUPERBLOCK_RO_ATTR(sb_write_time_secs); +NILFS_SUPERBLOCK_RO_ATTR(sb_write_count); +NILFS_SUPERBLOCK_RW_ATTR(sb_update_frequency); +NILFS_SUPERBLOCK_RO_ATTR(README); + +static struct attribute *nilfs_superblock_attrs[] = { + NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time), + NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time_secs), + NILFS_SUPERBLOCK_ATTR_LIST(sb_write_count), + NILFS_SUPERBLOCK_ATTR_LIST(sb_update_frequency), + NILFS_SUPERBLOCK_ATTR_LIST(README), + NULL, +}; + +NILFS_DEV_INT_GROUP_OPS(superblock, dev); +NILFS_DEV_INT_GROUP_TYPE(superblock, dev); +NILFS_DEV_INT_GROUP_FNS(superblock, dev); + /************************************************************************ * NILFS device attrs * ************************************************************************/ @@ -189,24 +385,44 @@ static struct kobj_type nilfs_dev_ktype = { int nilfs_sysfs_create_device_group(struct super_block *sb) { struct the_nilfs *nilfs = sb->s_fs_info; + size_t devgrp_size = sizeof(struct nilfs_sysfs_dev_subgroups); int err; + nilfs->ns_dev_subgroups = kzalloc(devgrp_size, GFP_KERNEL); + if (unlikely(!nilfs->ns_dev_subgroups)) { + err = -ENOMEM; + printk(KERN_ERR "NILFS: unable to allocate memory for device group\n"); + goto failed_create_device_group; + } + nilfs->ns_dev_kobj.kset = nilfs_kset; init_completion(&nilfs->ns_dev_kobj_unregister); err = kobject_init_and_add(&nilfs->ns_dev_kobj, &nilfs_dev_ktype, NULL, "%s", sb->s_id); if (err) - goto failed_create_device_group; + goto free_dev_subgroups; + + err = nilfs_sysfs_create_superblock_group(nilfs); + if (err) + goto cleanup_dev_kobject; return 0; +cleanup_dev_kobject: + kobject_del(&nilfs->ns_dev_kobj); + +free_dev_subgroups: + kfree(nilfs->ns_dev_subgroups); + failed_create_device_group: return err; } void nilfs_sysfs_delete_device_group(struct the_nilfs *nilfs) { + nilfs_sysfs_delete_superblock_group(nilfs); kobject_del(&nilfs->ns_dev_kobj); + kfree(nilfs->ns_dev_subgroups); } /************************************************************************ diff --git a/fs/nilfs2/sysfs.h b/fs/nilfs2/sysfs.h index 2353b28..1d76af5 100644 --- a/fs/nilfs2/sysfs.h +++ b/fs/nilfs2/sysfs.h @@ -24,6 +24,17 @@ #define NILFS_ROOT_GROUP_NAME "nilfs2" +/* + * struct nilfs_sysfs_dev_subgroups - device subgroup kernel objects + * @sg_superblock_kobj: /sys/fs///superblock + * @sg_superblock_kobj_unregister: completion state + */ +struct nilfs_sysfs_dev_subgroups { + /* /sys/fs///superblock */ + struct kobject sg_superblock_kobj; + struct completion sg_superblock_kobj_unregister; +}; + #define NILFS_COMMON_ATTR_STRUCT(name) \ struct nilfs_##name##_attr { \ struct attribute attr; \ @@ -45,6 +56,7 @@ struct nilfs_##name##_attr { \ }; NILFS_DEV_ATTR_STRUCT(dev); +NILFS_DEV_ATTR_STRUCT(superblock); #define NILFS_ATTR(type, name, mode, show, store) \ static struct nilfs_##type##_attr nilfs_##type##_attr_##name = \ @@ -73,9 +85,16 @@ NILFS_DEV_ATTR_STRUCT(dev); #define NILFS_DEV_RW_ATTR(name) \ NILFS_RW_ATTR(dev, name) +#define NILFS_SUPERBLOCK_RO_ATTR(name) \ + NILFS_RO_ATTR(superblock, name) +#define NILFS_SUPERBLOCK_RW_ATTR(name) \ + NILFS_RW_ATTR(superblock, name) + #define NILFS_FEATURE_ATTR_LIST(name) \ (&nilfs_feature_attr_##name.attr) #define NILFS_DEV_ATTR_LIST(name) \ (&nilfs_dev_attr_##name.attr) +#define NILFS_SUPERBLOCK_ATTR_LIST(name) \ + (&nilfs_superblock_attr_##name.attr) #endif /* _NILFS_SYSFS_H */ diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c index 8ba8229..59d5008 100644 --- a/fs/nilfs2/the_nilfs.c +++ b/fs/nilfs2/the_nilfs.c @@ -85,6 +85,7 @@ struct the_nilfs *alloc_nilfs(struct block_device *bdev) nilfs->ns_cptree = RB_ROOT; spin_lock_init(&nilfs->ns_cptree_lock); init_rwsem(&nilfs->ns_segctor_sem); + nilfs->ns_sb_update_freq = NILFS_SB_FREQ; return nilfs; } diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h index 34bc7bd..7fe8223 100644 --- a/fs/nilfs2/the_nilfs.h +++ b/fs/nilfs2/the_nilfs.h @@ -33,6 +33,7 @@ #include struct nilfs_sc_info; +struct nilfs_sysfs_dev_subgroups; /* the_nilfs struct */ enum { @@ -54,6 +55,7 @@ enum { * @ns_sbwcount: write count of super block * @ns_sbsize: size of valid data in super block * @ns_mount_state: file system state + * @ns_sb_update_freq: interval of periodical update of superblocks (in seconds) * @ns_seg_seq: segment sequence counter * @ns_segnum: index number of the latest full segment. * @ns_nextnum: index number of the full segment index to be used next @@ -97,6 +99,7 @@ enum { * @ns_crc_seed: seed value of CRC32 calculation * @ns_dev_kobj: /sys/fs// * @ns_dev_kobj_unregister: completion state + * @ns_dev_subgroups: subgroups pointer */ struct the_nilfs { unsigned long ns_flags; @@ -116,6 +119,7 @@ struct the_nilfs { unsigned ns_sbwcount; unsigned ns_sbsize; unsigned ns_mount_state; + unsigned ns_sb_update_freq; /* * Following fields are dedicated to a writable FS-instance. @@ -194,6 +198,7 @@ struct the_nilfs { /* /sys/fs// */ struct kobject ns_dev_kobj; struct completion ns_dev_kobj_unregister; + struct nilfs_sysfs_dev_subgroups *ns_dev_subgroups; }; #define THE_NILFS_FNS(bit, name) \ @@ -260,7 +265,8 @@ struct nilfs_root { static inline int nilfs_sb_need_update(struct the_nilfs *nilfs) { u64 t = get_seconds(); - return t < nilfs->ns_sbwtime || t > nilfs->ns_sbwtime + NILFS_SB_FREQ; + return t < nilfs->ns_sbwtime || + t > nilfs->ns_sbwtime + nilfs->ns_sb_update_freq; } static inline int nilfs_sb_will_flip(struct the_nilfs *nilfs) -- 2.7.4