Re: [f2fs-dev] [PATCH 1/2 v2] f2fs: expose /sys/fs/f2fs/features
From: Chao Yu
Date: Fri Jul 28 2017 - 08:41:09 EST
Hi Jaegeuk,
On 2017/7/27 5:44, Jaegeuk Kim wrote:
> Change log from v1:
> - add /sys/fs/f2fs/dev/features
>
> This patch exposes what features are supported by current f2fs build to sysfs
> entry via:
>
> /sys/fs/f2fs/features/> /sys/fs/f2fs/dev/features
>
> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> ---
> fs/f2fs/sysfs.c | 138 +++++++++++++++++++++++++++++++++++++++++++++-----------
> 1 file changed, 112 insertions(+), 26 deletions(-)
>
> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> index 5a78b9af92ef..83ab0dd73b2c 100644
> --- a/fs/f2fs/sysfs.c
> +++ b/fs/f2fs/sysfs.c
> @@ -18,7 +18,6 @@
> #include "gc.h"
>
> static struct proc_dir_entry *f2fs_proc_root;
> -static struct kset *f2fs_kset;
>
> /* Sysfs support for f2fs */
> enum {
> @@ -41,6 +40,7 @@ struct f2fs_attr {
> const char *, size_t);
> int struct_type;
> int offset;
> + int id;
> };
>
> static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
> @@ -76,6 +76,28 @@ static ssize_t lifetime_write_kbytes_show(struct f2fs_attr *a,
> BD_PART_WRITTEN(sbi)));
> }
>
> +static ssize_t features_show(struct f2fs_attr *a,
> + struct f2fs_sb_info *sbi, char *buf)
> +{
> + struct super_block *sb = sbi->sb;
> + int len = 0;
> +
> + if (!sb->s_bdev->bd_part)
> + return snprintf(buf, PAGE_SIZE, "0\n");
> +
> + if (f2fs_sb_has_crypto(sb))
> + len += snprintf(buf, PAGE_SIZE - len, "%s\n", "encryption");
How about printing as below:
len += snprintf(buf, PAGE_SIZE - len, "%s\n", "encryption ");
It avoids unneeded ',' in the beginning of output string:
cat /sys/fs/f2fs/zram0/features
, extra_attr, projquota, inode_checksum
> + if (f2fs_sb_mounted_blkzoned(sb))
> + len += snprintf(buf, PAGE_SIZE - len, "%s\n", ", blkzoned");
len += snprintf(buf, PAGE_SIZE - len, "%s\n", "blkzoned ");
> + if (f2fs_sb_has_extra_attr(sb))
> + len += snprintf(buf, PAGE_SIZE - len, "%s\n", ", extra_attr");
ditto
> + if (f2fs_sb_has_project_quota(sb))
> + len += snprintf(buf, PAGE_SIZE - len, "%s\n", ", projquota");
ditto
> + if (f2fs_sb_has_inode_chksum(sb))
> + len += snprintf(buf, PAGE_SIZE - len, "%s\n", ", inode_checksum");
ditto
> + return len;
> +}
> +
> static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
> struct f2fs_sb_info *sbi, char *buf)
> {
> @@ -155,6 +177,24 @@ static void f2fs_sb_release(struct kobject *kobj)
> complete(&sbi->s_kobj_unregister);
> }
>
> +enum feat_id {
> + FEAT_CRYPTO = 0,
> + FEAT_BLKZONED,
> + FEAT_ATOMIC_WRITE,
Adds below missing macro:
FEAT_EXTRA_ATTR,
FEAT_PROJECT_QUOTA,
FEAT_INODE_CHECKSUM,
> +};
> +
> +static ssize_t f2fs_feature_show(struct f2fs_attr *a,
> + struct f2fs_sb_info *sbi, char *buf)
> +{
> + switch (a->id) {
> + case FEAT_CRYPTO:
> + case FEAT_BLKZONED:
> + case FEAT_ATOMIC_WRITE:
case FEAT_EXTRA_ATTR:
case FEAT_PROJECT_QUOTA:
case FEAT_INODE_CHECKSUM:
> + return snprintf(buf, PAGE_SIZE, "supported\n");
> + }
> + return 0;
> +}
> +
> #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
> static struct f2fs_attr f2fs_attr_##_name = { \
> .attr = {.name = __stringify(_name), .mode = _mode }, \
> @@ -172,6 +212,13 @@ static struct f2fs_attr f2fs_attr_##_name = { \
> #define F2FS_GENERAL_RO_ATTR(name) \
> static struct f2fs_attr f2fs_attr_##name = __ATTR(name, 0444, name##_show, NULL)
>
> +#define F2FS_FEATURE_RO_ATTR(_name, _id) \
> +static struct f2fs_attr f2fs_attr_##_name = { \
> + .attr = {.name = __stringify(_name), .mode = 0444 }, \
> + .show = f2fs_feature_show, \
> + .id = _id, \
> +}
> +
> F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
> F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
> F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
> @@ -196,6 +243,15 @@ F2FS_RW_ATTR(FAULT_INFO_RATE, f2fs_fault_info, inject_rate, inject_rate);
> F2FS_RW_ATTR(FAULT_INFO_TYPE, f2fs_fault_info, inject_type, inject_type);
> #endif
> F2FS_GENERAL_RO_ATTR(lifetime_write_kbytes);
> +F2FS_GENERAL_RO_ATTR(features);
> +
> +#ifdef CONFIG_F2FS_FS_ENCRYPTION
> +F2FS_FEATURE_RO_ATTR(encryption, FEAT_CRYPTO);
> +#endif
> +#ifdef CONFIG_BLK_DEV_ZONED
> +F2FS_FEATURE_RO_ATTR(block_zoned, FEAT_BLKZONED);
> +#endif
> +F2FS_FEATURE_RO_ATTR(atomic_write, FEAT_ATOMIC_WRITE);
F2FS_FEATURE_RO_ATTR(extra_attr, FEAT_EXTRA_ATTR);
F2FS_FEATURE_RO_ATTR(project_quota, FEAT_PROJECT_QUOTA);
F2FS_FEATURE_RO_ATTR(inode_checksum, FEAT_INODE_CHECKSUM);
>
> #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
> static struct attribute *f2fs_attrs[] = {
> @@ -222,21 +278,50 @@ static struct attribute *f2fs_attrs[] = {
> ATTR_LIST(inject_type),
> #endif
> ATTR_LIST(lifetime_write_kbytes),
> + ATTR_LIST(features),
> ATTR_LIST(reserved_blocks),
> NULL,
> };
>
> +static struct attribute *f2fs_feat_attrs[] = {
> +#ifdef CONFIG_F2FS_FS_ENCRYPTION
> + ATTR_LIST(encryption),
> +#endif
> +#ifdef CONFIG_BLK_DEV_ZONED
> + ATTR_LIST(block_zoned),
> +#endif
> + ATTR_LIST(atomic_write),
ATTR_LIST(extra_attr),
ATTR_LIST(project_quota),
ATTR_LIST(inode_checksum),
Thanks,
> + NULL,
> +};
> +
> static const struct sysfs_ops f2fs_attr_ops = {
> .show = f2fs_attr_show,
> .store = f2fs_attr_store,
> };
>
> -static struct kobj_type f2fs_ktype = {
> +static struct kobj_type f2fs_sb_ktype = {
> .default_attrs = f2fs_attrs,
> .sysfs_ops = &f2fs_attr_ops,
> .release = f2fs_sb_release,
> };
>
> +static struct kobj_type f2fs_ktype = {
> + .sysfs_ops = &f2fs_attr_ops,
> +};
> +
> +static struct kset f2fs_kset = {
> + .kobj = {.ktype = &f2fs_ktype},
> +};
> +
> +static struct kobj_type f2fs_feat_ktype = {
> + .default_attrs = f2fs_feat_attrs,
> + .sysfs_ops = &f2fs_attr_ops,
> +};
> +
> +static struct kobject f2fs_feat = {
> + .kset = &f2fs_kset,
> +};
> +
> static int segment_info_seq_show(struct seq_file *seq, void *offset)
> {
> struct super_block *sb = seq->private;
> @@ -306,18 +391,29 @@ F2FS_PROC_FILE_DEF(segment_bits);
>
> int __init f2fs_init_sysfs(void)
> {
> - f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
> + int ret;
>
> - f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
> - if (!f2fs_kset)
> - return -ENOMEM;
> - return 0;
> + kobject_set_name(&f2fs_kset.kobj, "f2fs");
> + f2fs_kset.kobj.parent = fs_kobj;
> + ret = kset_register(&f2fs_kset);
> + if (ret)
> + return ret;
> +
> + ret = kobject_init_and_add(&f2fs_feat, &f2fs_feat_ktype,
> + NULL, "features");
> + if (ret)
> + kset_unregister(&f2fs_kset);
> + else
> + f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
> + return ret;
> }
>
> void f2fs_exit_sysfs(void)
> {
> - kset_unregister(f2fs_kset);
> + kobject_put(&f2fs_feat);
> + kset_unregister(&f2fs_kset);
> remove_proc_entry("fs/f2fs", NULL);
> + f2fs_proc_root = NULL;
> }
>
> int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
> @@ -325,6 +421,13 @@ int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
> struct super_block *sb = sbi->sb;
> int err;
>
> + sbi->s_kobj.kset = &f2fs_kset;
> + init_completion(&sbi->s_kobj_unregister);
> + err = kobject_init_and_add(&sbi->s_kobj, &f2fs_sb_ktype, NULL,
> + "%s", sb->s_id);
> + if (err)
> + return err;
> +
> if (f2fs_proc_root)
> sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
>
> @@ -334,32 +437,15 @@ int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
> proc_create_data("segment_bits", S_IRUGO, sbi->s_proc,
> &f2fs_seq_segment_bits_fops, sb);
> }
> -
> - sbi->s_kobj.kset = f2fs_kset;
> - init_completion(&sbi->s_kobj_unregister);
> - err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
> - "%s", sb->s_id);
> - if (err)
> - goto err_out;
> return 0;
> -err_out:
> - if (sbi->s_proc) {
> - remove_proc_entry("segment_info", sbi->s_proc);
> - remove_proc_entry("segment_bits", sbi->s_proc);
> - remove_proc_entry(sb->s_id, f2fs_proc_root);
> - }
> - return err;
> }
>
> void f2fs_unregister_sysfs(struct f2fs_sb_info *sbi)
> {
> - kobject_del(&sbi->s_kobj);
> - kobject_put(&sbi->s_kobj);
> - wait_for_completion(&sbi->s_kobj_unregister);
> -
> if (sbi->s_proc) {
> remove_proc_entry("segment_info", sbi->s_proc);
> remove_proc_entry("segment_bits", sbi->s_proc);
> remove_proc_entry(sbi->sb->s_id, f2fs_proc_root);
> }
> + kobject_del(&sbi->s_kobj);
> }
>