[PATCH v3 0/4] Add online file check feature

[PATCH v3 0/4] Add online file check feature

[Gang He]

When there are errors in the ocfs2 filesystem,
they are usually accompanied by the inode number which caused the error.
This inode number would be the input to fixing the file.
One of these options could be considered:
A file in the sys filesytem which would accept inode numbers.
This could be used to communication back what has to be fixed or is fixed.
You could write:
$# echo "<inode>" > /sys/fs/ocfs2/devname/filecheck/check
or
$# echo "<inode>" > /sys/fs/ocfs2/devname/filecheck/fix

Compare with second version, I re-design filecheck sysfs interfaces, there
are three sysfs files(check, fix and set) under filecheck directory(see above),
sysfs will accept only one argument <inode>. Second, I adjust some code in 
ocfs2_filecheck_repair_inode_block() function according to upstream feedback,
we cannot just add VALID_FL flag back as a inode block fix, then we will not 
fix this field corruption currently until having a complete solution.
Compare with first version, I use strncasecmp instead of double strncmp
functions. Second, update the source file contribution vendor.

Gang He (4):
  ocfs2: export ocfs2_kset for online file check
  ocfs2: sysfile interfaces for online file check
  ocfs2: create/remove sysfile for online file check
  ocfs2: check/fix inode block for online file check

 fs/ocfs2/Makefile      |   3 +-
 fs/ocfs2/filecheck.c   | 605 +++++++++++++++++++++++++++++++++++++++++++++++++
 fs/ocfs2/filecheck.h   |  48 ++++
 fs/ocfs2/inode.c       | 200 +++++++++++++++-
 fs/ocfs2/inode.h       |   3 +
 fs/ocfs2/ocfs2_trace.h |   2 +
 fs/ocfs2/stackglue.c   |   3 +-
 fs/ocfs2/stackglue.h   |   2 +
 fs/ocfs2/super.c       |   5 +
 9 files changed, 863 insertions(+), 8 deletions(-)
 create mode 100644 fs/ocfs2/filecheck.c
 create mode 100644 fs/ocfs2/filecheck.h

-- 
2.1.2

[PATCH v3 1/4] ocfs2: export ocfs2_kset for online file check

[Gang He]

Export ocfs2_kset object from ocfs2_stackglue kernel module,
then online file check code will create the related sysfiles
under ocfs2_kset object.

Signed-off-by: Gang He <ghe@suse.com>
---
 fs/ocfs2/stackglue.c | 3 ++-
 fs/ocfs2/stackglue.h | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index 5d965e8..13219ed 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -629,7 +629,8 @@ static struct attribute_group ocfs2_attr_group = {
 	.attrs = ocfs2_attrs,
 };
 
-static struct kset *ocfs2_kset;
+struct kset *ocfs2_kset;
+EXPORT_SYMBOL_GPL(ocfs2_kset);
 
 static void ocfs2_sysfs_exit(void)
 {
diff --git a/fs/ocfs2/stackglue.h b/fs/ocfs2/stackglue.h
index 66334a3..f2dce10 100644
--- a/fs/ocfs2/stackglue.h
+++ b/fs/ocfs2/stackglue.h
@@ -298,4 +298,6 @@ void ocfs2_stack_glue_set_max_proto_version(struct ocfs2_protocol_version *max_p
 int ocfs2_stack_glue_register(struct ocfs2_stack_plugin *plugin);
 void ocfs2_stack_glue_unregister(struct ocfs2_stack_plugin *plugin);
 
+extern struct kset *ocfs2_kset;
+
 #endif  /* STACKGLUE_H */
-- 
2.1.2

[PATCH v3 2/4] ocfs2: sysfile interfaces for online file check

[Gang He]

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>
---
 fs/ocfs2/Makefile    |   3 +-
 fs/ocfs2/filecheck.c | 605 +++++++++++++++++++++++++++++++++++++++++++++++++++
 fs/ocfs2/filecheck.h |  48 ++++
 fs/ocfs2/inode.h     |   3 +
 4 files changed, 658 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..a83e4ba
--- /dev/null
+++ b/fs/ocfs2/filecheck.c
@@ -0,0 +1,605 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * filecheck.c
+ *
+ * Code which implements online file check.
+ *
+ * Copyright (C) 2015 Novell.  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",
+	"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 short fe_done:1;
+	unsigned short fe_status:15;
+};
+
+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 short
+ocfs2_filecheck_handle(struct super_block *sb,
+		       unsigned long ino, unsigned int flags)
+{
+	unsigned short 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..5ec331b
--- /dev/null
+++ b/fs/ocfs2/filecheck.h
@@ -0,0 +1,48 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * filecheck.h
+ *
+ * Online file check.
+ *
+ * Copyright (C) 2015 Novell.  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_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);
-- 
2.1.2

[PATCH v3 3/4] ocfs2: create/remove sysfile for online file check

[Gang He]

Create online file check sysfile when ocfs2 mount,
remove the related sysfile when ocfs2 umount.

Signed-off-by: Gang He <ghe@suse.com>
---
 fs/ocfs2/super.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 2de4c8a..5ef88b8 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -74,6 +74,7 @@
 #include "suballoc.h"
 
 #include "buffer_head_io.h"
+#include "filecheck.h"
 
 static struct kmem_cache *ocfs2_inode_cachep;
 struct kmem_cache *ocfs2_dquot_cachep;
@@ -1204,6 +1205,9 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
 	/* Start this when the mount is almost sure of being successful */
 	ocfs2_orphan_scan_start(osb);
 
+	/* Create filecheck sysfile /sys/fs/ocfs2/<devname>/filecheck */
+	ocfs2_filecheck_create_sysfs(sb);
+
 	return status;
 
 read_super_error:
@@ -1671,6 +1675,7 @@ static void ocfs2_put_super(struct super_block *sb)
 
 	ocfs2_sync_blockdev(sb);
 	ocfs2_dismount_volume(sb, 0);
+	ocfs2_filecheck_remove_sysfs(sb);
 }
 
 static int ocfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
-- 
2.1.2

[PATCH v3 4/4] ocfs2: check/fix inode block for online file check

[Gang He]

Implement online check or fix inode block during
reading a inode block to memory.

Signed-off-by: Gang He <ghe@suse.com>
---
 fs/ocfs2/inode.c       | 200 +++++++++++++++++++++++++++++++++++++++++++++++--
 fs/ocfs2/ocfs2_trace.h |   2 +
 2 files changed, 196 insertions(+), 6 deletions(-)

diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 8f87e05..6ac2f19 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -53,6 +53,7 @@
 #include "xattr.h"
 #include "refcounttree.h"
 #include "ocfs2_trace.h"
+#include "filecheck.h"
 
 #include "buffer_head_io.h"
 
@@ -74,6 +75,14 @@ static int ocfs2_truncate_for_delete(struct ocfs2_super *osb,
 				    struct inode *inode,
 				    struct buffer_head *fe_bh);
 
+static int ocfs2_filecheck_read_inode_block_full(struct inode *inode,
+						 struct buffer_head **bh,
+						 int flags, int type);
+static int ocfs2_filecheck_validate_inode_block(struct super_block *sb,
+						struct buffer_head *bh);
+static int ocfs2_filecheck_repair_inode_block(struct super_block *sb,
+					      struct buffer_head *bh);
+
 void ocfs2_set_inode_flags(struct inode *inode)
 {
 	unsigned int flags = OCFS2_I(inode)->ip_attr;
@@ -127,6 +136,7 @@ struct inode *ocfs2_ilookup(struct super_block *sb, u64 blkno)
 struct inode *ocfs2_iget(struct ocfs2_super *osb, u64 blkno, unsigned flags,
 			 int sysfile_type)
 {
+	int rc = 0;
 	struct inode *inode = NULL;
 	struct super_block *sb = osb->sb;
 	struct ocfs2_find_inode_args args;
@@ -161,12 +171,17 @@ struct inode *ocfs2_iget(struct ocfs2_super *osb, u64 blkno, unsigned flags,
 	}
 	trace_ocfs2_iget5_locked(inode->i_state);
 	if (inode->i_state & I_NEW) {
-		ocfs2_read_locked_inode(inode, &args);
+		rc = ocfs2_read_locked_inode(inode, &args);
 		unlock_new_inode(inode);
 	}
 	if (is_bad_inode(inode)) {
 		iput(inode);
-		inode = ERR_PTR(-ESTALE);
+		if ((flags & OCFS2_FI_FLAG_FILECHECK_CHK) ||
+		    (flags & OCFS2_FI_FLAG_FILECHECK_FIX))
+			/* Return OCFS2_FILECHECK_ERR_XXX related errno */
+			inode = ERR_PTR(rc);
+		else
+			inode = ERR_PTR(-ESTALE);
 		goto bail;
 	}
 
@@ -494,16 +509,32 @@ static int ocfs2_read_locked_inode(struct inode *inode,
 	}
 
 	if (can_lock) {
-		status = ocfs2_read_inode_block_full(inode, &bh,
-						     OCFS2_BH_IGNORE_CACHE);
+		if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_CHK)
+			status = ocfs2_filecheck_read_inode_block_full(inode,
+						&bh, OCFS2_BH_IGNORE_CACHE, 0);
+		else if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_FIX)
+			status = ocfs2_filecheck_read_inode_block_full(inode,
+						&bh, OCFS2_BH_IGNORE_CACHE, 1);
+		else
+			status = ocfs2_read_inode_block_full(inode,
+						&bh, OCFS2_BH_IGNORE_CACHE);
 	} else {
 		status = ocfs2_read_blocks_sync(osb, args->fi_blkno, 1, &bh);
 		/*
 		 * If buffer is in jbd, then its checksum may not have been
 		 * computed as yet.
 		 */
-		if (!status && !buffer_jbd(bh))
-			status = ocfs2_validate_inode_block(osb->sb, bh);
+		if (!status && !buffer_jbd(bh)) {
+			if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_CHK)
+				status = ocfs2_filecheck_validate_inode_block(
+								osb->sb, bh);
+			else if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_FIX)
+				status = ocfs2_filecheck_repair_inode_block(
+								osb->sb, bh);
+			else
+				status = ocfs2_validate_inode_block(
+								osb->sb, bh);
+		}
 	}
 	if (status < 0) {
 		mlog_errno(status);
@@ -531,6 +562,14 @@ static int ocfs2_read_locked_inode(struct inode *inode,
 
 	BUG_ON(args->fi_blkno != le64_to_cpu(fe->i_blkno));
 
+	if (buffer_dirty(bh)) {
+		status = ocfs2_write_block(osb, bh, INODE_CACHE(inode));
+		if (status < 0) {
+			mlog_errno(status);
+			goto bail;
+		}
+	}
+
 	status = 0;
 
 bail:
@@ -1396,6 +1435,155 @@ bail:
 	return rc;
 }
 
+static int ocfs2_filecheck_validate_inode_block(struct super_block *sb,
+						struct buffer_head *bh)
+{
+	int rc = 0;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)bh->b_data;
+
+	trace_ocfs2_filecheck_validate_inode_block(
+		(unsigned long long)bh->b_blocknr);
+
+	BUG_ON(!buffer_uptodate(bh));
+
+	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &di->i_check);
+	if (rc) {
+		mlog(ML_ERROR,
+		     "Filecheck: checksum failed for dinode %llu\n",
+		     (unsigned long long)bh->b_blocknr);
+		rc = -OCFS2_FILECHECK_ERR_BLOCKECC;
+		goto bail;
+	}
+
+	if (!OCFS2_IS_VALID_DINODE(di)) {
+		mlog(ML_ERROR,
+		     "Filecheck: invalid dinode #%llu: signature = %.*s\n",
+		     (unsigned long long)bh->b_blocknr, 7, di->i_signature);
+		rc = -OCFS2_FILECHECK_ERR_INVALIDINO;
+		goto bail;
+	}
+
+	if (le64_to_cpu(di->i_blkno) != bh->b_blocknr) {
+		mlog(ML_ERROR,
+		     "Filecheck: invalid dinode #%llu: i_blkno is %llu\n",
+		     (unsigned long long)bh->b_blocknr,
+		     (unsigned long long)le64_to_cpu(di->i_blkno));
+		rc = -OCFS2_FILECHECK_ERR_BLOCKNO;
+		goto bail;
+	}
+
+	if (!(di->i_flags & cpu_to_le32(OCFS2_VALID_FL))) {
+		mlog(ML_ERROR,
+		     "Filecheck: invalid dinode #%llu: OCFS2_VALID_FL "
+		     "not set\n",
+		     (unsigned long long)bh->b_blocknr);
+		rc = -OCFS2_FILECHECK_ERR_VALIDFLAG;
+		goto bail;
+	}
+
+	if (le32_to_cpu(di->i_fs_generation) !=
+	    OCFS2_SB(sb)->fs_generation) {
+		mlog(ML_ERROR,
+		     "Filecheck: invalid dinode #%llu: fs_generation is %u\n",
+		     (unsigned long long)bh->b_blocknr,
+		     le32_to_cpu(di->i_fs_generation));
+		rc = -OCFS2_FILECHECK_ERR_GENERATION;
+		goto bail;
+	}
+
+bail:
+	return rc;
+}
+
+static int ocfs2_filecheck_repair_inode_block(struct super_block *sb,
+					      struct buffer_head *bh)
+{
+	int changed = 0;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)bh->b_data;
+
+	if (!ocfs2_filecheck_validate_inode_block(sb, bh))
+		return 0;
+
+	trace_ocfs2_filecheck_repair_inode_block(
+		(unsigned long long)bh->b_blocknr);
+
+	if (ocfs2_is_hard_readonly(OCFS2_SB(sb)) ||
+	    ocfs2_is_soft_readonly(OCFS2_SB(sb))) {
+		mlog(ML_ERROR,
+		     "Filecheck: cannot repair dinode #%llu "
+		     "on readonly filesystem\n",
+		     (unsigned long long)bh->b_blocknr);
+		return -OCFS2_FILECHECK_ERR_READONLY;
+	}
+
+	if (!OCFS2_IS_VALID_DINODE(di)) {
+		/* Cannot fix invalid inode block */
+		return -OCFS2_FILECHECK_ERR_INVALIDINO;
+	}
+
+	if (!(di->i_flags & cpu_to_le32(OCFS2_VALID_FL))) {
+		/* Cannot just add VALID_FL flag back as a fix,
+		 * need more things to check here.
+		 */
+		return -OCFS2_FILECHECK_ERR_VALIDFLAG;
+	}
+
+	if (le64_to_cpu(di->i_blkno) != bh->b_blocknr) {
+		di->i_blkno = cpu_to_le64(bh->b_blocknr);
+		changed = 1;
+		mlog(ML_ERROR,
+		     "Filecheck: reset dinode #%llu: i_blkno to %llu\n",
+		     (unsigned long long)bh->b_blocknr,
+		     (unsigned long long)le64_to_cpu(di->i_blkno));
+	}
+
+	if (le32_to_cpu(di->i_fs_generation) !=
+	    OCFS2_SB(sb)->fs_generation) {
+		di->i_fs_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation);
+		changed = 1;
+		mlog(ML_ERROR,
+		     "Filecheck: reset dinode #%llu: fs_generation to %u\n",
+		     (unsigned long long)bh->b_blocknr,
+		     le32_to_cpu(di->i_fs_generation));
+	}
+
+	if (changed || ocfs2_validate_meta_ecc(sb, bh->b_data, &di->i_check)) {
+		ocfs2_compute_meta_ecc(sb, bh->b_data, &di->i_check);
+		mark_buffer_dirty(bh);
+		mlog(ML_ERROR,
+		     "Filecheck: reset dinode #%llu: compute meta ecc\n",
+		     (unsigned long long)bh->b_blocknr);
+	}
+
+	return 0;
+}
+
+static int
+ocfs2_filecheck_read_inode_block_full(struct inode *inode,
+				      struct buffer_head **bh,
+				      int flags, int type)
+{
+	int rc;
+	struct buffer_head *tmp = *bh;
+
+	if (!type) /* Check inode block */
+		rc = ocfs2_read_blocks(INODE_CACHE(inode),
+				OCFS2_I(inode)->ip_blkno,
+				1, &tmp, flags,
+				ocfs2_filecheck_validate_inode_block);
+	else /* Repair inode block */
+		rc = ocfs2_read_blocks(INODE_CACHE(inode),
+				OCFS2_I(inode)->ip_blkno,
+				1, &tmp, flags,
+				ocfs2_filecheck_repair_inode_block);
+
+	/* If ocfs2_read_blocks() got us a new bh, pass it up. */
+	if (!rc && !*bh)
+		*bh = tmp;
+
+	return rc;
+}
+
 int ocfs2_read_inode_block_full(struct inode *inode, struct buffer_head **bh,
 				int flags)
 {
diff --git a/fs/ocfs2/ocfs2_trace.h b/fs/ocfs2/ocfs2_trace.h
index 6cb019b..d9205e0 100644
--- a/fs/ocfs2/ocfs2_trace.h
+++ b/fs/ocfs2/ocfs2_trace.h
@@ -1540,6 +1540,8 @@ DEFINE_OCFS2_ULL_INT_EVENT(ocfs2_read_locked_inode);
 DEFINE_OCFS2_INT_INT_EVENT(ocfs2_check_orphan_recovery_state);
 
 DEFINE_OCFS2_ULL_EVENT(ocfs2_validate_inode_block);
+DEFINE_OCFS2_ULL_EVENT(ocfs2_filecheck_validate_inode_block);
+DEFINE_OCFS2_ULL_EVENT(ocfs2_filecheck_repair_inode_block);
 
 TRACE_EVENT(ocfs2_inode_is_valid_to_delete,
 	TP_PROTO(void *task, void *dc_task, unsigned long long ino,
-- 
2.1.2

Re: [PATCH v3 1/4] ocfs2: export ocfs2_kset for online file check

[Andrew Morton]

On Fri, 25 Dec 2015 15:16:16 +0800 Gang He <ghe@suse.com> wrote:

> Export ocfs2_kset object from ocfs2_stackglue kernel module,
> then online file check code will create the related sysfiles
> under ocfs2_kset object.
> 
> ...
>
> --- a/fs/ocfs2/stackglue.c
> +++ b/fs/ocfs2/stackglue.c
> @@ -629,7 +629,8 @@ static struct attribute_group ocfs2_attr_group = {
>  	.attrs = ocfs2_attrs,
>  };
>  
> -static struct kset *ocfs2_kset;
> +struct kset *ocfs2_kset;
> +EXPORT_SYMBOL_GPL(ocfs2_kset);

The EXPORT_SYMBOL is only needed if this symbol is to be referred to
from a different module.  That isn't the case here - everything which
refers to ocfs2_kset is linked into ocfs2.ko, correct?

Re: [PATCH v3 0/4] Add online file check feature

[Andrew Morton]

On Fri, 25 Dec 2015 15:16:15 +0800 Gang He <ghe@suse.com> wrote:

> When there are errors in the ocfs2 filesystem,
> they are usually accompanied by the inode number which caused the error.
> This inode number would be the input to fixing the file.
> One of these options could be considered:
> A file in the sys filesytem which would accept inode numbers.
> This could be used to communication back what has to be fixed or is fixed.
> You could write:
> $# echo "<inode>" > /sys/fs/ocfs2/devname/filecheck/check
> or
> $# echo "<inode>" > /sys/fs/ocfs2/devname/filecheck/fix
> 
> Compare with second version, I re-design filecheck sysfs interfaces, there
> are three sysfs files(check, fix and set) under filecheck directory(see above),
> sysfs will accept only one argument <inode>. Second, I adjust some code in 
> ocfs2_filecheck_repair_inode_block() function according to upstream feedback,
> we cannot just add VALID_FL flag back as a inode block fix, then we will not 
> fix this field corruption currently until having a complete solution.
> Compare with first version, I use strncasecmp instead of double strncmp
> functions. Second, update the source file contribution vendor.

This feature should be documented, please.  That means all pseudo-file
locations, all inputs, all outputs, expected behaviour etc etc.  Enough
info so that our users can usefully and fully use this feature in the
minimum time.  Documentation/filesystems/ocfs2.txt is the place for that.

Re: [PATCH v3 0/4] Add online file check feature

[Gang He]

Hello Andrew  and Mark,


>>> 
> On Fri, 25 Dec 2015 15:16:15 +0800 Gang He <ghe@suse.com> wrote:
> 
>> When there are errors in the ocfs2 filesystem,
>> they are usually accompanied by the inode number which caused the error.
>> This inode number would be the input to fixing the file.
>> One of these options could be considered:
>> A file in the sys filesytem which would accept inode numbers.
>> This could be used to communication back what has to be fixed or is fixed.
>> You could write:
>> $# echo "<inode>" > /sys/fs/ocfs2/devname/filecheck/check
>> or
>> $# echo "<inode>" > /sys/fs/ocfs2/devname/filecheck/fix
>> 
>> Compare with second version, I re-design filecheck sysfs interfaces, there
>> are three sysfs files(check, fix and set) under filecheck directory(see 
> above),
>> sysfs will accept only one argument <inode>. Second, I adjust some code in 
>> ocfs2_filecheck_repair_inode_block() function according to upstream 
> feedback,
>> we cannot just add VALID_FL flag back as a inode block fix, then we will not 
> 
>> fix this field corruption currently until having a complete solution.
>> Compare with first version, I use strncasecmp instead of double strncmp
>> functions. Second, update the source file contribution vendor.
>  
> This feature should be documented, please.  That means all pseudo-file
> locations, all inputs, all outputs, expected behaviour etc etc.  Enough
> info so that our users can usefully and fully use this feature in the
> minimum time.  Documentation/filesystems/ocfs2.txt is the place for that.
I ever sent out a document which describes this feature, I will modify that document sightly since sysfs interfaces have been adjusted,
then send out to the list as a separated patch. Is it OK for you?

Thanks
Gang

Re: [PATCH v3 0/4] Add online file check feature

[Andrew Morton]

On Tue, 29 Dec 2015 20:00:08 -0700 "Gang He" <ghe@suse.com> wrote:

> > This feature should be documented, please.  That means all pseudo-file
> > locations, all inputs, all outputs, expected behaviour etc etc.  Enough
> > info so that our users can usefully and fully use this feature in the
> > minimum time.  Documentation/filesystems/ocfs2.txt is the place for that.
> I ever sent out a document which describes this feature, I will modify that document sightly since sysfs interfaces have been adjusted,
> then send out to the list as a separated patch. Is it OK for you?

Sounds good, thanks.  The documentation is important because it permits
reviewers to understand the proposed interfaces, which need to be
nailed down before there's any point in looking at the implementation.

Re: [PATCH v3 1/4] ocfs2: export ocfs2_kset for online file check

[Gang He]

Hello Andrew,


>>> 
> On Fri, 25 Dec 2015 15:16:16 +0800 Gang He <ghe@suse.com> wrote:
> 
>> Export ocfs2_kset object from ocfs2_stackglue kernel module,
>> then online file check code will create the related sysfiles
>> under ocfs2_kset object.
>> 
>> ...
>>
>> --- a/fs/ocfs2/stackglue.c
>> +++ b/fs/ocfs2/stackglue.c
>> @@ -629,7 +629,8 @@ static struct attribute_group ocfs2_attr_group = {
>>  	.attrs = ocfs2_attrs,
>>  };
>>  
>> -static struct kset *ocfs2_kset;
>> +struct kset *ocfs2_kset;
>> +EXPORT_SYMBOL_GPL(ocfs2_kset);
> 
> The EXPORT_SYMBOL is only needed if this symbol is to be referred to
> from a different module.  That isn't the case here - everything which
> refers to ocfs2_kset is linked into ocfs2.ko, correct?
There are some kernel modules (Not single KO file) for OCFS2 file system, the variable ocfs2_kset is located in ocfs2_stackglue.ko kernel module,
if the main kernel module ocfs2.ko wants to refer to this variable, it looks to have to export this symbol? 

Thanks
Gang  

Re: [PATCH v3 1/4] ocfs2: export ocfs2_kset for online file check

[Mark Fasheh]

On Fri, Dec 25, 2015 at 03:16:16PM +0800, Gang He wrote:
> Export ocfs2_kset object from ocfs2_stackglue kernel module,
> then online file check code will create the related sysfiles
> under ocfs2_kset object.
> 
> Signed-off-by: Gang He <ghe@suse.com>

Reviewed-by: Mark Fasheh <mfasheh@suse.de>

This was easy to review, though you might consider adding a note that we're
exporting this because it's built in ocfs2_stackglue.ko.
	--Mark


> ---
>  fs/ocfs2/stackglue.c | 3 ++-
>  fs/ocfs2/stackglue.h | 2 ++
>  2 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
> index 5d965e8..13219ed 100644
> --- a/fs/ocfs2/stackglue.c
> +++ b/fs/ocfs2/stackglue.c
> @@ -629,7 +629,8 @@ static struct attribute_group ocfs2_attr_group = {
>  	.attrs = ocfs2_attrs,
>  };
>  
> -static struct kset *ocfs2_kset;
> +struct kset *ocfs2_kset;
> +EXPORT_SYMBOL_GPL(ocfs2_kset);
>  
>  static void ocfs2_sysfs_exit(void)
>  {
> diff --git a/fs/ocfs2/stackglue.h b/fs/ocfs2/stackglue.h
> index 66334a3..f2dce10 100644
> --- a/fs/ocfs2/stackglue.h
> +++ b/fs/ocfs2/stackglue.h
> @@ -298,4 +298,6 @@ void ocfs2_stack_glue_set_max_proto_version(struct ocfs2_protocol_version *max_p
>  int ocfs2_stack_glue_register(struct ocfs2_stack_plugin *plugin);
>  void ocfs2_stack_glue_unregister(struct ocfs2_stack_plugin *plugin);
>  
> +extern struct kset *ocfs2_kset;
> +
>  #endif  /* STACKGLUE_H */
> -- 
> 2.1.2
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
--
Mark Fasheh

Re: [PATCH v3 1/4] ocfs2: export ocfs2_kset for online file check

[Andrew Morton]

On Wed, 13 Jan 2016 15:02:28 -0800 Mark Fasheh <mfasheh@suse.de> wrote:

> On Fri, Dec 25, 2015 at 03:16:16PM +0800, Gang He wrote:
> > Export ocfs2_kset object from ocfs2_stackglue kernel module,
> > then online file check code will create the related sysfiles
> > under ocfs2_kset object.
> > 
> > Signed-off-by: Gang He <ghe@suse.com>
> 
> Reviewed-by: Mark Fasheh <mfasheh@suse.de>
> 
> This was easy to review, though you might consider adding a note that we're
> exporting this because it's built in ocfs2_stackglue.ko.

I've updated the changelog to reflect that.  (copy-n-paste is still in
my skillset).

Re: [PATCH v3 2/4] ocfs2: sysfile interfaces for online file check

[Mark Fasheh]

On Fri, Dec 25, 2015 at 03:16:17PM +0800, 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>

Most of this looks good, I have two comments below. Also thank you for
redoing the interface to be more sysfs friendly.


> diff --git a/fs/ocfs2/filecheck.c b/fs/ocfs2/filecheck.c
> new file mode 100644
> index 0000000..a83e4ba
> --- /dev/null
> +++ b/fs/ocfs2/filecheck.c
> @@ -0,0 +1,605 @@
> +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 */

What is the point of fc_max? Only root can initiate file check so we need
not worry about a malicious user eating up our memory. That should let us
drop a bunch of the code below that is concerned with setting/reporting it.


> +	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 short fe_done:1;
> +	unsigned short fe_status:15;

I don't see the need to use a short here (or bitfield) for fc_status. IMHO
it is less error-prone if we just make it an int or unsigned int.


This is a bit off topic but I dream of the day when we can return errors
which userspace undestands but are outside the tiny range of 0-255  :)

Thanks,
	--Mark

--
Mark Fasheh

Re: [PATCH v3 3/4] ocfs2: create/remove sysfile for online file check

[Mark Fasheh]

On Fri, Dec 25, 2015 at 03:16:18PM +0800, Gang He wrote:
> Create online file check sysfile when ocfs2 mount,
> remove the related sysfile when ocfs2 umount.
> 
> Signed-off-by: Gang He <ghe@suse.com>

Reviewed-by: Mark Fasheh <mfasheh@suse.de>
	--Mark

--
Mark Fasheh

Re: [Ocfs2-devel] [PATCH v3 4/4] ocfs2: check/fix inode block for online file check

[Mark Fasheh]

On Fri, Dec 25, 2015 at 03:16:19PM +0800, Gang He wrote:
> Implement online check or fix inode block during
> reading a inode block to memory.
> 
> Signed-off-by: Gang He <ghe@suse.com>
> ---
>  fs/ocfs2/inode.c       | 200 +++++++++++++++++++++++++++++++++++++++++++++++--
>  fs/ocfs2/ocfs2_trace.h |   2 +
>  2 files changed, 196 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
> index 8f87e05..6ac2f19 100644
> --- a/fs/ocfs2/inode.c
> +++ b/fs/ocfs2/inode.c
> @@ -53,6 +53,7 @@
>  #include "xattr.h"
>  #include "refcounttree.h"
>  #include "ocfs2_trace.h"
> +#include "filecheck.h"
>  
>  #include "buffer_head_io.h"
>  
> @@ -74,6 +75,14 @@ static int ocfs2_truncate_for_delete(struct ocfs2_super *osb,
>  				    struct inode *inode,
>  				    struct buffer_head *fe_bh);
>  
> +static int ocfs2_filecheck_read_inode_block_full(struct inode *inode,
> +						 struct buffer_head **bh,
> +						 int flags, int type);
> +static int ocfs2_filecheck_validate_inode_block(struct super_block *sb,
> +						struct buffer_head *bh);
> +static int ocfs2_filecheck_repair_inode_block(struct super_block *sb,
> +					      struct buffer_head *bh);
> +
>  void ocfs2_set_inode_flags(struct inode *inode)
>  {
>  	unsigned int flags = OCFS2_I(inode)->ip_attr;
> @@ -127,6 +136,7 @@ struct inode *ocfs2_ilookup(struct super_block *sb, u64 blkno)
>  struct inode *ocfs2_iget(struct ocfs2_super *osb, u64 blkno, unsigned flags,
>  			 int sysfile_type)
>  {
> +	int rc = 0;
>  	struct inode *inode = NULL;
>  	struct super_block *sb = osb->sb;
>  	struct ocfs2_find_inode_args args;
> @@ -161,12 +171,17 @@ struct inode *ocfs2_iget(struct ocfs2_super *osb, u64 blkno, unsigned flags,
>  	}
>  	trace_ocfs2_iget5_locked(inode->i_state);
>  	if (inode->i_state & I_NEW) {
> -		ocfs2_read_locked_inode(inode, &args);
> +		rc = ocfs2_read_locked_inode(inode, &args);
>  		unlock_new_inode(inode);
>  	}
>  	if (is_bad_inode(inode)) {
>  		iput(inode);
> -		inode = ERR_PTR(-ESTALE);
> +		if ((flags & OCFS2_FI_FLAG_FILECHECK_CHK) ||
> +		    (flags & OCFS2_FI_FLAG_FILECHECK_FIX))
> +			/* Return OCFS2_FILECHECK_ERR_XXX related errno */
> +			inode = ERR_PTR(rc);
> +		else
> +			inode = ERR_PTR(-ESTALE);
>  		goto bail;
>  	}
>  
> @@ -494,16 +509,32 @@ static int ocfs2_read_locked_inode(struct inode *inode,
>  	}
>  
>  	if (can_lock) {
> -		status = ocfs2_read_inode_block_full(inode, &bh,
> -						     OCFS2_BH_IGNORE_CACHE);
> +		if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_CHK)
> +			status = ocfs2_filecheck_read_inode_block_full(inode,
> +						&bh, OCFS2_BH_IGNORE_CACHE, 0);
> +		else if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_FIX)
> +			status = ocfs2_filecheck_read_inode_block_full(inode,
> +						&bh, OCFS2_BH_IGNORE_CACHE, 1);
> +		else
> +			status = ocfs2_read_inode_block_full(inode,
> +						&bh, OCFS2_BH_IGNORE_CACHE);
>  	} else {
>  		status = ocfs2_read_blocks_sync(osb, args->fi_blkno, 1, &bh);
>  		/*
>  		 * If buffer is in jbd, then its checksum may not have been
>  		 * computed as yet.
>  		 */
> -		if (!status && !buffer_jbd(bh))
> -			status = ocfs2_validate_inode_block(osb->sb, bh);
> +		if (!status && !buffer_jbd(bh)) {
> +			if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_CHK)
> +				status = ocfs2_filecheck_validate_inode_block(
> +								osb->sb, bh);
> +			else if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_FIX)
> +				status = ocfs2_filecheck_repair_inode_block(
> +								osb->sb, bh);
> +			else
> +				status = ocfs2_validate_inode_block(
> +								osb->sb, bh);
> +		}
>  	}
>  	if (status < 0) {
>  		mlog_errno(status);
> @@ -531,6 +562,14 @@ static int ocfs2_read_locked_inode(struct inode *inode,
>  
>  	BUG_ON(args->fi_blkno != le64_to_cpu(fe->i_blkno));
>  
> +	if (buffer_dirty(bh)) {
> +		status = ocfs2_write_block(osb, bh, INODE_CACHE(inode));
> +		if (status < 0) {
> +			mlog_errno(status);
> +			goto bail;
> +		}
> +	}

This reminds me, we should be checking for a readonly file system up top in
the 'fix' helper.

Also, I'm concerned that the buffer in question might be journaled. In that
case, writing it to disk like this could cause corruptions (if the buffer
contains not-committed changes).

The answer might be to journal the changes we make but I'm not sure if that
can deadlock with other iget() calls.
	--Mark

--
Mark Fasheh

Re: [PATCH v3 2/4] ocfs2: sysfile interfaces for online file check

[Gang He]

Hello Mark,


>>> 
> On Fri, Dec 25, 2015 at 03:16:17PM +0800, 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>
> 
> Most of this looks good, I have two comments below. Also thank you for
> redoing the interface to be more sysfs friendly.
> 
> 
>> diff --git a/fs/ocfs2/filecheck.c b/fs/ocfs2/filecheck.c
>> new file mode 100644
>> index 0000000..a83e4ba
>> --- /dev/null
>> +++ b/fs/ocfs2/filecheck.c
>> @@ -0,0 +1,605 @@
>> +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 */
> 
> What is the point of fc_max? Only root can initiate file check so we need
> not worry about a malicious user eating up our memory. That should let us
> drop a bunch of the code below that is concerned with setting/reporting it.
the fc_max item is used to set the maximum number of file check entry (include doing and finished) in the list,
this means the kernel module will keep how many filecheck results (history records) at most when uses cat sysfile to inquire the filecheck results.
the kernel module will not cache all finished filecheck results, I think we need a value to limit this size.

> 
> 
>> +	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 short fe_done:1;
>> +	unsigned short fe_status:15;
> 
> I don't see the need to use a short here (or bitfield) for fc_status. IMHO
> it is less error-prone if we just make it an int or unsigned int.
OK, I will make it an unsigned int type, but a bit field have to be used to indicate this file check entry is done, or under processing. 
Since we use this flag (fe_done) when we shrink the result records, we only can get rid of finished entries. 

> 
> 
> This is a bit off topic but I dream of the day when we can return errors
> which userspace undestands but are outside the tiny range of 0-255  :)
Yes, this is why we return a error string in the result, not a error number.
 Second, these file check errors (most) are not generic, then we can not utilize system error numbers. 

> 
> Thanks,
> 	--Mark
> 
> --
> Mark Fasheh

Re: [Ocfs2-devel] [PATCH v3 4/4] ocfs2: check/fix inode block for online file check

[Gang He]

Hello Mark,


>>> 
> On Fri, Dec 25, 2015 at 03:16:19PM +0800, Gang He wrote:
>> Implement online check or fix inode block during
>> reading a inode block to memory.
>> 
>> Signed-off-by: Gang He <ghe@suse.com>
>> ---
>>  fs/ocfs2/inode.c       | 200 
> +++++++++++++++++++++++++++++++++++++++++++++++--
>>  fs/ocfs2/ocfs2_trace.h |   2 +
>>  2 files changed, 196 insertions(+), 6 deletions(-)
>> 
>> diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
>> index 8f87e05..6ac2f19 100644
>> --- a/fs/ocfs2/inode.c
>> +++ b/fs/ocfs2/inode.c
>> @@ -53,6 +53,7 @@
>>  #include "xattr.h"
>>  #include "refcounttree.h"
>>  #include "ocfs2_trace.h"
>> +#include "filecheck.h"
>>  
>>  #include "buffer_head_io.h"
>>  
>> @@ -74,6 +75,14 @@ static int ocfs2_truncate_for_delete(struct ocfs2_super 
> *osb,
>>  				    struct inode *inode,
>>  				    struct buffer_head *fe_bh);
>>  
>> +static int ocfs2_filecheck_read_inode_block_full(struct inode *inode,
>> +						 struct buffer_head **bh,
>> +						 int flags, int type);
>> +static int ocfs2_filecheck_validate_inode_block(struct super_block *sb,
>> +						struct buffer_head *bh);
>> +static int ocfs2_filecheck_repair_inode_block(struct super_block *sb,
>> +					      struct buffer_head *bh);
>> +
>>  void ocfs2_set_inode_flags(struct inode *inode)
>>  {
>>  	unsigned int flags = OCFS2_I(inode)->ip_attr;
>> @@ -127,6 +136,7 @@ struct inode *ocfs2_ilookup(struct super_block *sb, u64 
> blkno)
>>  struct inode *ocfs2_iget(struct ocfs2_super *osb, u64 blkno, unsigned 
> flags,
>>  			 int sysfile_type)
>>  {
>> +	int rc = 0;
>>  	struct inode *inode = NULL;
>>  	struct super_block *sb = osb->sb;
>>  	struct ocfs2_find_inode_args args;
>> @@ -161,12 +171,17 @@ struct inode *ocfs2_iget(struct ocfs2_super *osb, u64 
> blkno, unsigned flags,
>>  	}
>>  	trace_ocfs2_iget5_locked(inode->i_state);
>>  	if (inode->i_state & I_NEW) {
>> -		ocfs2_read_locked_inode(inode, &args);
>> +		rc = ocfs2_read_locked_inode(inode, &args);
>>  		unlock_new_inode(inode);
>>  	}
>>  	if (is_bad_inode(inode)) {
>>  		iput(inode);
>> -		inode = ERR_PTR(-ESTALE);
>> +		if ((flags & OCFS2_FI_FLAG_FILECHECK_CHK) ||
>> +		    (flags & OCFS2_FI_FLAG_FILECHECK_FIX))
>> +			/* Return OCFS2_FILECHECK_ERR_XXX related errno */
>> +			inode = ERR_PTR(rc);
>> +		else
>> +			inode = ERR_PTR(-ESTALE);
>>  		goto bail;
>>  	}
>>  
>> @@ -494,16 +509,32 @@ static int ocfs2_read_locked_inode(struct inode *inode,
>>  	}
>>  
>>  	if (can_lock) {
>> -		status = ocfs2_read_inode_block_full(inode, &bh,
>> -						     OCFS2_BH_IGNORE_CACHE);
>> +		if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_CHK)
>> +			status = ocfs2_filecheck_read_inode_block_full(inode,
>> +						&bh, OCFS2_BH_IGNORE_CACHE, 0);
>> +		else if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_FIX)
>> +			status = ocfs2_filecheck_read_inode_block_full(inode,
>> +						&bh, OCFS2_BH_IGNORE_CACHE, 1);
>> +		else
>> +			status = ocfs2_read_inode_block_full(inode,
>> +						&bh, OCFS2_BH_IGNORE_CACHE);
>>  	} else {
>>  		status = ocfs2_read_blocks_sync(osb, args->fi_blkno, 1, &bh);
>>  		/*
>>  		 * If buffer is in jbd, then its checksum may not have been
>>  		 * computed as yet.
>>  		 */
>> -		if (!status && !buffer_jbd(bh))
>> -			status = ocfs2_validate_inode_block(osb->sb, bh);
>> +		if (!status && !buffer_jbd(bh)) {
>> +			if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_CHK)
>> +				status = ocfs2_filecheck_validate_inode_block(
>> +								osb->sb, bh);
>> +			else if (args->fi_flags & OCFS2_FI_FLAG_FILECHECK_FIX)
>> +				status = ocfs2_filecheck_repair_inode_block(
>> +								osb->sb, bh);
>> +			else
>> +				status = ocfs2_validate_inode_block(
>> +								osb->sb, bh);
>> +		}
>>  	}
>>  	if (status < 0) {
>>  		mlog_errno(status);
>> @@ -531,6 +562,14 @@ static int ocfs2_read_locked_inode(struct inode *inode,
>>  
>>  	BUG_ON(args->fi_blkno != le64_to_cpu(fe->i_blkno));
>>  
>> +	if (buffer_dirty(bh)) {
>> +		status = ocfs2_write_block(osb, bh, INODE_CACHE(inode));
>> +		if (status < 0) {
>> +			mlog_errno(status);
>> +			goto bail;
>> +		}
>> +	}
> 
> This reminds me, we should be checking for a readonly file system up top in
> the 'fix' helper.
When the file system becomes read-only, we still can check certain file via it's inode number and report the result (the inode block is integrated or not),
but we cannot fix this file in file system read-only status, otherwise the subsequent logic will become too complex in case we modify/write a inode block under a read-only file system.
Actually, online file check feature should be combined with "errors=continues" option for better using.

> 
> Also, I'm concerned that the buffer in question might be journaled. In that 
> case, writing it to disk like this could cause corruptions (if the buffer
> contains not-committed changes). 
I ever though of journaling this changed inode block in case file check fixing, but you know, we are being on inode block loading stage, the journal related structs are not prepared at this moment, then I write this block back to the disk synchronously within ocfs2_inode_lock, it looks a little tricky, but not bring any risk. in case the machine crashes when writing the inode block back to the disk, this will not affect file system integrity, since this inode block original is corrupted, the user can fix this inode block via file check again after the machine is recovered.
Anyway, I just want to let all know what I think behind this part code, maybe it is not right, please give your feedback again.

Thanks
Gang

 
> 
> The answer might be to journal the changes we make but I'm not sure if that
> can deadlock with other iget() calls.
> 	--Mark
> 
> --
> Mark Fasheh