Subject: Re: [Ocfs2-devel] [PATCH v4 2/5] ocfs2: sysfile interfaces for online
 file check
To: Gang He <ghe@suse.com>, mfasheh@suse.com, rgoldwyn@suse.de
References: <1456723082-13838-1-git-send-email-ghe@suse.com>
 <1456723082-13838-3-git-send-email-ghe@suse.com>
Cc: linux-kernel@vger.kernel.org, ocfs2-devel@oss.oracle.com
From: Eric Ren <zren@suse.com>
Message-ID: <56DFB756.2090305@suse.com>
Date: Wed, 9 Mar 2016 13:40:38 +0800
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On 02/29/2016 01:17 PM, Gang He wrote:
> Implement online file check sysfile interfaces, e.g.
> how to create the related sysfile according to device name,
> how to display/handle file check request from the sysfile.
>
> Signed-off-by: Gang He <ghe@suse.com>
Tested-by: Eric Ren <zren@suse.com>
> ---
>   fs/ocfs2/Makefile    |   3 +-
>   fs/ocfs2/filecheck.c | 606 +++++++++++++++++++++++++++++++++++++++++++++++++++
>   fs/ocfs2/filecheck.h |  49 +++++
>   fs/ocfs2/inode.h     |   3 +
>   4 files changed, 660 insertions(+), 1 deletion(-)
>   create mode 100644 fs/ocfs2/filecheck.c
>   create mode 100644 fs/ocfs2/filecheck.h
>
> diff --git a/fs/ocfs2/Makefile b/fs/ocfs2/Makefile
> index ce210d4..e27e652 100644
> --- a/fs/ocfs2/Makefile
> +++ b/fs/ocfs2/Makefile
> @@ -41,7 +41,8 @@ ocfs2-objs := \
>   	quota_local.o		\
>   	quota_global.o		\
>   	xattr.o			\
> -	acl.o
> +	acl.o	\
> +	filecheck.o
>   
>   ocfs2_stackglue-objs := stackglue.o
>   ocfs2_stack_o2cb-objs := stack_o2cb.o
> diff --git a/fs/ocfs2/filecheck.c b/fs/ocfs2/filecheck.c
> new file mode 100644
> index 0000000..2cabbcf
> --- /dev/null
> +++ b/fs/ocfs2/filecheck.c
> @@ -0,0 +1,606 @@
> +/* -*- mode: c; c-basic-offset: 8; -*-
> + * vim: noexpandtab sw=8 ts=8 sts=0:
> + *
> + * filecheck.c
> + *
> + * Code which implements online file check.
> + *
> + * Copyright (C) 2016 SuSE.  All rights reserved.
> + *
> + * 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, version 2.
> + *
> + * 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.
> + */
> +
> +#include <linux/list.h>
> +#include <linux/spinlock.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include <linux/kmod.h>
> +#include <linux/fs.h>
> +#include <linux/kobject.h>
> +#include <linux/sysfs.h>
> +#include <linux/sysctl.h>
> +#include <cluster/masklog.h>
> +
> +#include "ocfs2.h"
> +#include "ocfs2_fs.h"
> +#include "stackglue.h"
> +#include "inode.h"
> +
> +#include "filecheck.h"
> +
> +
> +/* File check error strings,
> + * must correspond with error number in header file.
> + */
> +static const char * const ocfs2_filecheck_errs[] = {
> +	"SUCCESS",
> +	"FAILED",
> +	"INPROGRESS",
> +	"READONLY",
> +	"INJBD",
> +	"INVALIDINO",
> +	"BLOCKECC",
> +	"BLOCKNO",
> +	"VALIDFLAG",
> +	"GENERATION",
> +	"UNSUPPORTED"
> +};
> +
> +static DEFINE_SPINLOCK(ocfs2_filecheck_sysfs_lock);
> +static LIST_HEAD(ocfs2_filecheck_sysfs_list);
> +
> +struct ocfs2_filecheck {
> +	struct list_head fc_head;	/* File check entry list head */
> +	spinlock_t fc_lock;
> +	unsigned int fc_max;	/* Maximum number of entry in list */
> +	unsigned int fc_size;	/* Current entry count in list */
> +	unsigned int fc_done;	/* Finished entry count in list */
> +};
> +
> +struct ocfs2_filecheck_sysfs_entry {	/* sysfs entry per mounting */
> +	struct list_head fs_list;
> +	atomic_t fs_count;
> +	struct super_block *fs_sb;
> +	struct kset *fs_devicekset;
> +	struct kset *fs_fcheckkset;
> +	struct ocfs2_filecheck *fs_fcheck;
> +};
> +
> +#define OCFS2_FILECHECK_MAXSIZE		100
> +#define OCFS2_FILECHECK_MINSIZE		10
> +
> +/* File check operation type */
> +enum {
> +	OCFS2_FILECHECK_TYPE_CHK = 0,	/* Check a file(inode) */
> +	OCFS2_FILECHECK_TYPE_FIX,	/* Fix a file(inode) */
> +	OCFS2_FILECHECK_TYPE_SET = 100	/* Set entry list maximum size */
> +};
> +
> +struct ocfs2_filecheck_entry {
> +	struct list_head fe_list;
> +	unsigned long fe_ino;
> +	unsigned int fe_type;
> +	unsigned int fe_done:1;
> +	unsigned int fe_status:31;
> +};
> +
> +struct ocfs2_filecheck_args {
> +	unsigned int fa_type;
> +	union {
> +		unsigned long fa_ino;
> +		unsigned int fa_len;
> +	};
> +};
> +
> +static const char *
> +ocfs2_filecheck_error(int errno)
> +{
> +	if (!errno)
> +		return ocfs2_filecheck_errs[errno];
> +
> +	BUG_ON(errno < OCFS2_FILECHECK_ERR_START ||
> +	       errno > OCFS2_FILECHECK_ERR_END);
> +	return ocfs2_filecheck_errs[errno - OCFS2_FILECHECK_ERR_START + 1];
> +}
> +
> +static ssize_t ocfs2_filecheck_show(struct kobject *kobj,
> +				    struct kobj_attribute *attr,
> +				    char *buf);
> +static ssize_t ocfs2_filecheck_store(struct kobject *kobj,
> +				     struct kobj_attribute *attr,
> +				     const char *buf, size_t count);
> +static struct kobj_attribute ocfs2_attr_filecheck_chk =
> +					__ATTR(check, S_IRUSR | S_IWUSR,
> +					ocfs2_filecheck_show,
> +					ocfs2_filecheck_store);
> +static struct kobj_attribute ocfs2_attr_filecheck_fix =
> +					__ATTR(fix, S_IRUSR | S_IWUSR,
> +					ocfs2_filecheck_show,
> +					ocfs2_filecheck_store);
> +static struct kobj_attribute ocfs2_attr_filecheck_set =
> +					__ATTR(set, S_IRUSR | S_IWUSR,
> +					ocfs2_filecheck_show,
> +					ocfs2_filecheck_store);
> +
> +static int ocfs2_filecheck_sysfs_wait(atomic_t *p)
> +{
> +	schedule();
> +	return 0;
> +}
> +
> +static void
> +ocfs2_filecheck_sysfs_free(struct ocfs2_filecheck_sysfs_entry *entry)
> +{
> +	struct ocfs2_filecheck_entry *p;
> +
> +	if (!atomic_dec_and_test(&entry->fs_count))
> +		wait_on_atomic_t(&entry->fs_count, ocfs2_filecheck_sysfs_wait,
> +				 TASK_UNINTERRUPTIBLE);
> +
> +	spin_lock(&entry->fs_fcheck->fc_lock);
> +	while (!list_empty(&entry->fs_fcheck->fc_head)) {
> +		p = list_first_entry(&entry->fs_fcheck->fc_head,
> +				     struct ocfs2_filecheck_entry, fe_list);
> +		list_del(&p->fe_list);
> +		BUG_ON(!p->fe_done); /* To free a undone file check entry */
> +		kfree(p);
> +	}
> +	spin_unlock(&entry->fs_fcheck->fc_lock);
> +
> +	kset_unregister(entry->fs_fcheckkset);
> +	kset_unregister(entry->fs_devicekset);
> +	kfree(entry->fs_fcheck);
> +	kfree(entry);
> +}
> +
> +static void
> +ocfs2_filecheck_sysfs_add(struct ocfs2_filecheck_sysfs_entry *entry)
> +{
> +	spin_lock(&ocfs2_filecheck_sysfs_lock);
> +	list_add_tail(&entry->fs_list, &ocfs2_filecheck_sysfs_list);
> +	spin_unlock(&ocfs2_filecheck_sysfs_lock);
> +}
> +
> +static int ocfs2_filecheck_sysfs_del(const char *devname)
> +{
> +	struct ocfs2_filecheck_sysfs_entry *p;
> +
> +	spin_lock(&ocfs2_filecheck_sysfs_lock);
> +	list_for_each_entry(p, &ocfs2_filecheck_sysfs_list, fs_list) {
> +		if (!strcmp(p->fs_sb->s_id, devname)) {
> +			list_del(&p->fs_list);
> +			spin_unlock(&ocfs2_filecheck_sysfs_lock);
> +			ocfs2_filecheck_sysfs_free(p);
> +			return 0;
> +		}
> +	}
> +	spin_unlock(&ocfs2_filecheck_sysfs_lock);
> +	return 1;
> +}
> +
> +static void
> +ocfs2_filecheck_sysfs_put(struct ocfs2_filecheck_sysfs_entry *entry)
> +{
> +	if (atomic_dec_and_test(&entry->fs_count))
> +		wake_up_atomic_t(&entry->fs_count);
> +}
> +
> +static struct ocfs2_filecheck_sysfs_entry *
> +ocfs2_filecheck_sysfs_get(const char *devname)
> +{
> +	struct ocfs2_filecheck_sysfs_entry *p = NULL;
> +
> +	spin_lock(&ocfs2_filecheck_sysfs_lock);
> +	list_for_each_entry(p, &ocfs2_filecheck_sysfs_list, fs_list) {
> +		if (!strcmp(p->fs_sb->s_id, devname)) {
> +			atomic_inc(&p->fs_count);
> +			spin_unlock(&ocfs2_filecheck_sysfs_lock);
> +			return p;
> +		}
> +	}
> +	spin_unlock(&ocfs2_filecheck_sysfs_lock);
> +	return NULL;
> +}
> +
> +int ocfs2_filecheck_create_sysfs(struct super_block *sb)
> +{
> +	int ret = 0;
> +	struct kset *device_kset = NULL;
> +	struct kset *fcheck_kset = NULL;
> +	struct ocfs2_filecheck *fcheck = NULL;
> +	struct ocfs2_filecheck_sysfs_entry *entry = NULL;
> +	struct attribute **attrs = NULL;
> +	struct attribute_group attrgp;
> +
> +	if (!ocfs2_kset)
> +		return -ENOMEM;
> +
> +	attrs = kmalloc(sizeof(struct attribute *) * 4, GFP_NOFS);
> +	if (!attrs) {
> +		ret = -ENOMEM;
> +		goto error;
> +	} else {
> +		attrs[0] = &ocfs2_attr_filecheck_chk.attr;
> +		attrs[1] = &ocfs2_attr_filecheck_fix.attr;
> +		attrs[2] = &ocfs2_attr_filecheck_set.attr;
> +		attrs[3] = NULL;
> +		memset(&attrgp, 0, sizeof(attrgp));
> +		attrgp.attrs = attrs;
> +	}
> +
> +	fcheck = kmalloc(sizeof(struct ocfs2_filecheck), GFP_NOFS);
> +	if (!fcheck) {
> +		ret = -ENOMEM;
> +		goto error;
> +	} else {
> +		INIT_LIST_HEAD(&fcheck->fc_head);
> +		spin_lock_init(&fcheck->fc_lock);
> +		fcheck->fc_max = OCFS2_FILECHECK_MINSIZE;
> +		fcheck->fc_size = 0;
> +		fcheck->fc_done = 0;
> +	}
> +
> +	if (strlen(sb->s_id) <= 0) {
> +		mlog(ML_ERROR,
> +		"Cannot get device basename when create filecheck sysfs\n");
> +		ret = -ENODEV;
> +		goto error;
> +	}
> +
> +	device_kset = kset_create_and_add(sb->s_id, NULL, &ocfs2_kset->kobj);
> +	if (!device_kset) {
> +		ret = -ENOMEM;
> +		goto error;
> +	}
> +
> +	fcheck_kset = kset_create_and_add("filecheck", NULL,
> +					  &device_kset->kobj);
> +	if (!fcheck_kset) {
> +		ret = -ENOMEM;
> +		goto error;
> +	}
> +
> +	ret = sysfs_create_group(&fcheck_kset->kobj, &attrgp);
> +	if (ret)
> +		goto error;
> +
> +	entry = kmalloc(sizeof(struct ocfs2_filecheck_sysfs_entry), GFP_NOFS);
> +	if (!entry) {
> +		ret = -ENOMEM;
> +		goto error;
> +	} else {
> +		atomic_set(&entry->fs_count, 1);
> +		entry->fs_sb = sb;
> +		entry->fs_devicekset = device_kset;
> +		entry->fs_fcheckkset = fcheck_kset;
> +		entry->fs_fcheck = fcheck;
> +		ocfs2_filecheck_sysfs_add(entry);
> +	}
> +
> +	kfree(attrs);
> +	return 0;
> +
> +error:
> +	kfree(attrs);
> +	kfree(entry);
> +	kfree(fcheck);
> +	kset_unregister(fcheck_kset);
> +	kset_unregister(device_kset);
> +	return ret;
> +}
> +
> +int ocfs2_filecheck_remove_sysfs(struct super_block *sb)
> +{
> +	return ocfs2_filecheck_sysfs_del(sb->s_id);
> +}
> +
> +static int
> +ocfs2_filecheck_erase_entries(struct ocfs2_filecheck_sysfs_entry *ent,
> +			      unsigned int count);
> +static int
> +ocfs2_filecheck_adjust_max(struct ocfs2_filecheck_sysfs_entry *ent,
> +			   unsigned int len)
> +{
> +	int ret;
> +
> +	if ((len < OCFS2_FILECHECK_MINSIZE) || (len > OCFS2_FILECHECK_MAXSIZE))
> +		return -EINVAL;
> +
> +	spin_lock(&ent->fs_fcheck->fc_lock);
> +	if (len < (ent->fs_fcheck->fc_size - ent->fs_fcheck->fc_done)) {
> +		mlog(ML_ERROR,
> +		"Cannot set online file check maximum entry number "
> +		"to %u due to too many pending entries(%u)\n",
> +		len, ent->fs_fcheck->fc_size - ent->fs_fcheck->fc_done);
> +		ret = -EBUSY;
> +	} else {
> +		if (len < ent->fs_fcheck->fc_size)
> +			BUG_ON(!ocfs2_filecheck_erase_entries(ent,
> +				ent->fs_fcheck->fc_size - len));
> +
> +		ent->fs_fcheck->fc_max = len;
> +		ret = 0;
> +	}
> +	spin_unlock(&ent->fs_fcheck->fc_lock);
> +
> +	return ret;
> +}
> +
> +#define OCFS2_FILECHECK_ARGS_LEN	24
> +static int
> +ocfs2_filecheck_args_get_long(const char *buf, size_t count,
> +			      unsigned long *val)
> +{
> +	char buffer[OCFS2_FILECHECK_ARGS_LEN];
> +
> +	memcpy(buffer, buf, count);
> +	buffer[count] = '\0';
> +
> +	if (kstrtoul(buffer, 0, val))
> +		return 1;
> +
> +	return 0;
> +}
> +
> +static int
> +ocfs2_filecheck_type_parse(const char *name, unsigned int *type)
> +{
> +	if (!strncmp(name, "fix", 4))
> +		*type = OCFS2_FILECHECK_TYPE_FIX;
> +	else if (!strncmp(name, "check", 6))
> +		*type = OCFS2_FILECHECK_TYPE_CHK;
> +	else if (!strncmp(name, "set", 4))
> +		*type = OCFS2_FILECHECK_TYPE_SET;
> +	else
> +		return 1;
> +
> +	return 0;
> +}
> +
> +static int
> +ocfs2_filecheck_args_parse(const char *name, const char *buf, size_t count,
> +			   struct ocfs2_filecheck_args *args)
> +{
> +	unsigned long val = 0;
> +	unsigned int type;
> +
> +	/* too short/long args length */
> +	if ((count < 1) || (count >= OCFS2_FILECHECK_ARGS_LEN))
> +		return 1;
> +
> +	if (ocfs2_filecheck_type_parse(name, &type))
> +		return 1;
> +	if (ocfs2_filecheck_args_get_long(buf, count, &val))
> +		return 1;
> +
> +	if (val <= 0)
> +		return 1;
> +
> +	args->fa_type = type;
> +	if (type == OCFS2_FILECHECK_TYPE_SET)
> +		args->fa_len = (unsigned int)val;
> +	else
> +		args->fa_ino = val;
> +
> +	return 0;
> +}
> +
> +static ssize_t ocfs2_filecheck_show(struct kobject *kobj,
> +				    struct kobj_attribute *attr,
> +				    char *buf)
> +{
> +
> +	ssize_t ret = 0, total = 0, remain = PAGE_SIZE;
> +	unsigned int type;
> +	struct ocfs2_filecheck_entry *p;
> +	struct ocfs2_filecheck_sysfs_entry *ent;
> +
> +	if (ocfs2_filecheck_type_parse(attr->attr.name, &type))
> +		return -EINVAL;
> +
> +	ent = ocfs2_filecheck_sysfs_get(kobj->parent->name);
> +	if (!ent) {
> +		mlog(ML_ERROR,
> +		"Cannot get the corresponding entry via device basename %s\n",
> +		kobj->name);
> +		return -ENODEV;
> +	}
> +
> +	if (type == OCFS2_FILECHECK_TYPE_SET) {
> +		spin_lock(&ent->fs_fcheck->fc_lock);
> +		total = snprintf(buf, remain, "%u\n", ent->fs_fcheck->fc_max);
> +		spin_unlock(&ent->fs_fcheck->fc_lock);
> +		goto exit;
> +	}
> +
> +	ret = snprintf(buf, remain, "INO\t\tDONE\tERROR\n");
> +	total += ret;
> +	remain -= ret;
> +	spin_lock(&ent->fs_fcheck->fc_lock);
> +	list_for_each_entry(p, &ent->fs_fcheck->fc_head, fe_list) {
> +		if (p->fe_type != type)
> +			continue;
> +
> +		ret = snprintf(buf + total, remain, "%lu\t\t%u\t%s\n",
> +			       p->fe_ino, p->fe_done,
> +			       ocfs2_filecheck_error(p->fe_status));
> +		if (ret < 0) {
> +			total = ret;
> +			break;
> +		}
> +		if (ret == remain) {
> +			/* snprintf() didn't fit */
> +			total = -E2BIG;
> +			break;
> +		}
> +		total += ret;
> +		remain -= ret;
> +	}
> +	spin_unlock(&ent->fs_fcheck->fc_lock);
> +
> +exit:
> +	ocfs2_filecheck_sysfs_put(ent);
> +	return total;
> +}
> +
> +static int
> +ocfs2_filecheck_erase_entry(struct ocfs2_filecheck_sysfs_entry *ent)
> +{
> +	struct ocfs2_filecheck_entry *p;
> +
> +	list_for_each_entry(p, &ent->fs_fcheck->fc_head, fe_list) {
> +		if (p->fe_done) {
> +			list_del(&p->fe_list);
> +			kfree(p);
> +			ent->fs_fcheck->fc_size--;
> +			ent->fs_fcheck->fc_done--;
> +			return 1;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int
> +ocfs2_filecheck_erase_entries(struct ocfs2_filecheck_sysfs_entry *ent,
> +			      unsigned int count)
> +{
> +	unsigned int i = 0;
> +	unsigned int ret = 0;
> +
> +	while (i++ < count) {
> +		if (ocfs2_filecheck_erase_entry(ent))
> +			ret++;
> +		else
> +			break;
> +	}
> +
> +	return (ret == count ? 1 : 0);
> +}
> +
> +static void
> +ocfs2_filecheck_done_entry(struct ocfs2_filecheck_sysfs_entry *ent,
> +			   struct ocfs2_filecheck_entry *entry)
> +{
> +	entry->fe_done = 1;
> +	spin_lock(&ent->fs_fcheck->fc_lock);
> +	ent->fs_fcheck->fc_done++;
> +	spin_unlock(&ent->fs_fcheck->fc_lock);
> +}
> +
> +static unsigned int
> +ocfs2_filecheck_handle(struct super_block *sb,
> +		       unsigned long ino, unsigned int flags)
> +{
> +	unsigned int ret = OCFS2_FILECHECK_ERR_SUCCESS;
> +	struct inode *inode = NULL;
> +	int rc;
> +
> +	inode = ocfs2_iget(OCFS2_SB(sb), ino, flags, 0);
> +	if (IS_ERR(inode)) {
> +		rc = (int)(-(long)inode);
> +		if (rc >= OCFS2_FILECHECK_ERR_START &&
> +		    rc < OCFS2_FILECHECK_ERR_END)
> +			ret = rc;
> +		else
> +			ret = OCFS2_FILECHECK_ERR_FAILED;
> +	} else
> +		iput(inode);
> +
> +	return ret;
> +}
> +
> +static void
> +ocfs2_filecheck_handle_entry(struct ocfs2_filecheck_sysfs_entry *ent,
> +			     struct ocfs2_filecheck_entry *entry)
> +{
> +	if (entry->fe_type == OCFS2_FILECHECK_TYPE_CHK)
> +		entry->fe_status = ocfs2_filecheck_handle(ent->fs_sb,
> +				entry->fe_ino, OCFS2_FI_FLAG_FILECHECK_CHK);
> +	else if (entry->fe_type == OCFS2_FILECHECK_TYPE_FIX)
> +		entry->fe_status = ocfs2_filecheck_handle(ent->fs_sb,
> +				entry->fe_ino, OCFS2_FI_FLAG_FILECHECK_FIX);
> +	else
> +		entry->fe_status = OCFS2_FILECHECK_ERR_UNSUPPORTED;
> +
> +	ocfs2_filecheck_done_entry(ent, entry);
> +}
> +
> +static ssize_t ocfs2_filecheck_store(struct kobject *kobj,
> +				     struct kobj_attribute *attr,
> +				     const char *buf, size_t count)
> +{
> +	struct ocfs2_filecheck_args args;
> +	struct ocfs2_filecheck_entry *entry;
> +	struct ocfs2_filecheck_sysfs_entry *ent;
> +	ssize_t ret = 0;
> +
> +	if (count == 0)
> +		return count;
> +
> +	if (ocfs2_filecheck_args_parse(attr->attr.name, buf, count, &args)) {
> +		mlog(ML_ERROR, "Invalid arguments for online file check\n");
> +		return -EINVAL;
> +	}
> +
> +	ent = ocfs2_filecheck_sysfs_get(kobj->parent->name);
> +	if (!ent) {
> +		mlog(ML_ERROR,
> +		"Cannot get the corresponding entry via device basename %s\n",
> +		kobj->parent->name);
> +		return -ENODEV;
> +	}
> +
> +	if (args.fa_type == OCFS2_FILECHECK_TYPE_SET) {
> +		ret = ocfs2_filecheck_adjust_max(ent, args.fa_len);
> +		goto exit;
> +	}
> +
> +	entry = kmalloc(sizeof(struct ocfs2_filecheck_entry), GFP_NOFS);
> +	if (!entry) {
> +		ret = -ENOMEM;
> +		goto exit;
> +	}
> +
> +	spin_lock(&ent->fs_fcheck->fc_lock);
> +	if ((ent->fs_fcheck->fc_size >= ent->fs_fcheck->fc_max) &&
> +	    (ent->fs_fcheck->fc_done == 0)) {
> +		mlog(ML_ERROR,
> +		"Cannot do more file check "
> +		"since file check queue(%u) is full now\n",
> +		ent->fs_fcheck->fc_max);
> +		ret = -EBUSY;
> +		kfree(entry);
> +	} else {
> +		if ((ent->fs_fcheck->fc_size >= ent->fs_fcheck->fc_max) &&
> +		    (ent->fs_fcheck->fc_done > 0)) {
> +			/* Delete the oldest entry which was done,
> +			 * make sure the entry size in list does
> +			 * not exceed maximum value
> +			 */
> +			BUG_ON(!ocfs2_filecheck_erase_entry(ent));
> +		}
> +
> +		entry->fe_ino = args.fa_ino;
> +		entry->fe_type = args.fa_type;
> +		entry->fe_done = 0;
> +		entry->fe_status = OCFS2_FILECHECK_ERR_INPROGRESS;
> +		list_add_tail(&entry->fe_list, &ent->fs_fcheck->fc_head);
> +		ent->fs_fcheck->fc_size++;
> +	}
> +	spin_unlock(&ent->fs_fcheck->fc_lock);
> +
> +	if (!ret)
> +		ocfs2_filecheck_handle_entry(ent, entry);
> +
> +exit:
> +	ocfs2_filecheck_sysfs_put(ent);
> +	return (!ret ? count : ret);
> +}
> diff --git a/fs/ocfs2/filecheck.h b/fs/ocfs2/filecheck.h
> new file mode 100644
> index 0000000..e5cd002
> --- /dev/null
> +++ b/fs/ocfs2/filecheck.h
> @@ -0,0 +1,49 @@
> +/* -*- mode: c; c-basic-offset: 8; -*-
> + * vim: noexpandtab sw=8 ts=8 sts=0:
> + *
> + * filecheck.h
> + *
> + * Online file check.
> + *
> + * Copyright (C) 2016 SuSE.  All rights reserved.
> + *
> + * 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, version 2.
> + *
> + * 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.
> + */
> +
> +
> +#ifndef FILECHECK_H
> +#define FILECHECK_H
> +
> +#include <linux/types.h>
> +#include <linux/list.h>
> +
> +
> +/* File check errno */
> +enum {
> +	OCFS2_FILECHECK_ERR_SUCCESS = 0,	/* Success */
> +	OCFS2_FILECHECK_ERR_FAILED = 1000,	/* Other failure */
> +	OCFS2_FILECHECK_ERR_INPROGRESS,		/* In progress */
> +	OCFS2_FILECHECK_ERR_READONLY,		/* Read only */
> +	OCFS2_FILECHECK_ERR_INJBD,		/* Buffer in jbd */
> +	OCFS2_FILECHECK_ERR_INVALIDINO,		/* Invalid ino */
> +	OCFS2_FILECHECK_ERR_BLOCKECC,		/* Block ecc */
> +	OCFS2_FILECHECK_ERR_BLOCKNO,		/* Block number */
> +	OCFS2_FILECHECK_ERR_VALIDFLAG,		/* Inode valid flag */
> +	OCFS2_FILECHECK_ERR_GENERATION,		/* Inode generation */
> +	OCFS2_FILECHECK_ERR_UNSUPPORTED		/* Unsupported */
> +};
> +
> +#define OCFS2_FILECHECK_ERR_START	OCFS2_FILECHECK_ERR_FAILED
> +#define OCFS2_FILECHECK_ERR_END		OCFS2_FILECHECK_ERR_UNSUPPORTED
> +
> +int ocfs2_filecheck_create_sysfs(struct super_block *sb);
> +int ocfs2_filecheck_remove_sysfs(struct super_block *sb);
> +
> +#endif  /* FILECHECK_H */
> diff --git a/fs/ocfs2/inode.h b/fs/ocfs2/inode.h
> index aac8b86..01635e0 100644
> --- a/fs/ocfs2/inode.h
> +++ b/fs/ocfs2/inode.h
> @@ -139,6 +139,9 @@ int ocfs2_drop_inode(struct inode *inode);
>   /* Flags for ocfs2_iget() */
>   #define OCFS2_FI_FLAG_SYSFILE		0x1
>   #define OCFS2_FI_FLAG_ORPHAN_RECOVERY	0x2
> +#define OCFS2_FI_FLAG_FILECHECK_CHK	0x4
> +#define OCFS2_FI_FLAG_FILECHECK_FIX	0x8
> +
>   struct inode *ocfs2_ilookup(struct super_block *sb, u64 feoff);
>   struct inode *ocfs2_iget(struct ocfs2_super *osb, u64 feoff, unsigned flags,
>   			 int sysfile_type);