linux-brain/fs/ocfs2/cluster/masklog.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* -*- mode: c; c-basic-offset: 8; -*-
 * vim: noexpandtab sw=8 ts=8 sts=0:
 *
 * Copyright (C) 2004, 2005 Oracle.  All rights reserved.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/uaccess.h>

#include "masklog.h"

struct mlog_bits mlog_and_bits = MLOG_BITS_RHS(MLOG_INITIAL_AND_MASK);
EXPORT_SYMBOL_GPL(mlog_and_bits);
struct mlog_bits mlog_not_bits = MLOG_BITS_RHS(0);
EXPORT_SYMBOL_GPL(mlog_not_bits);

static ssize_t mlog_mask_show(u64 mask, char *buf)
{
	char *state;

	if (__mlog_test_u64(mask, mlog_and_bits))
		state = "allow";
	else if (__mlog_test_u64(mask, mlog_not_bits))
		state = "deny";
	else
		state = "off";

	return snprintf(buf, PAGE_SIZE, "%s\n", state);
}

static ssize_t mlog_mask_store(u64 mask, const char *buf, size_t count)
{
	if (!strncasecmp(buf, "allow", 5)) {
		__mlog_set_u64(mask, mlog_and_bits);
		__mlog_clear_u64(mask, mlog_not_bits);
	} else if (!strncasecmp(buf, "deny", 4)) {
		__mlog_set_u64(mask, mlog_not_bits);
		__mlog_clear_u64(mask, mlog_and_bits);
	} else if (!strncasecmp(buf, "off", 3)) {
		__mlog_clear_u64(mask, mlog_not_bits);
		__mlog_clear_u64(mask, mlog_and_bits);
	} else
		return -EINVAL;

	return count;
}

void __mlog_printk(const u64 *mask, const char *func, int line,
		   const char *fmt, ...)
{
	struct va_format vaf;
	va_list args;
	const char *level;
	const char *prefix = "";

	if (!__mlog_test_u64(*mask, mlog_and_bits) ||
	    __mlog_test_u64(*mask, mlog_not_bits))
		return;

	if (*mask & ML_ERROR) {
		level = KERN_ERR;
		prefix = "ERROR: ";
	} else if (*mask & ML_NOTICE) {
		level = KERN_NOTICE;
	} else {
		level = KERN_INFO;
	}

	va_start(args, fmt);

	vaf.fmt = fmt;
	vaf.va = &args;

	printk("%s(%s,%u,%u):%s:%d %s%pV",
	       level, current->comm, task_pid_nr(current),
	       raw_smp_processor_id(), func, line, prefix, &vaf);

	va_end(args);
}
EXPORT_SYMBOL_GPL(__mlog_printk);

struct mlog_attribute {
	struct attribute attr;
	u64 mask;
};

#define to_mlog_attr(_attr) container_of(_attr, struct mlog_attribute, attr)

#define define_mask(_name) {			\
	.attr = {				\
		.name = #_name,			\
		.mode = S_IRUGO | S_IWUSR,	\
	},					\
	.mask = ML_##_name,			\
}

static struct mlog_attribute mlog_attrs[MLOG_MAX_BITS] = {
	define_mask(TCP),
	define_mask(MSG),
	define_mask(SOCKET),
	define_mask(HEARTBEAT),
	define_mask(HB_BIO),
	define_mask(DLMFS),
	define_mask(DLM),
	define_mask(DLM_DOMAIN),
	define_mask(DLM_THREAD),
	define_mask(DLM_MASTER),
	define_mask(DLM_RECOVERY),
	define_mask(DLM_GLUE),
	define_mask(VOTE),
	define_mask(CONN),
	define_mask(QUORUM),
	define_mask(BASTS),
	define_mask(CLUSTER),
	define_mask(ERROR),
	define_mask(NOTICE),
	define_mask(KTHREAD),
};

static struct attribute *mlog_attr_ptrs[MLOG_MAX_BITS] = {NULL, };

static ssize_t mlog_show(struct kobject *obj, struct attribute *attr,
			 char *buf)
{
	struct mlog_attribute *mlog_attr = to_mlog_attr(attr);

	return mlog_mask_show(mlog_attr->mask, buf);
}

static ssize_t mlog_store(struct kobject *obj, struct attribute *attr,
			  const char *buf, size_t count)
{
	struct mlog_attribute *mlog_attr = to_mlog_attr(attr);

	return mlog_mask_store(mlog_attr->mask, buf, count);
}

static const struct sysfs_ops mlog_attr_ops = {
	.show  = mlog_show,
	.store = mlog_store,
};

static struct kobj_type mlog_ktype = {
	.default_attrs = mlog_attr_ptrs,
	.sysfs_ops     = &mlog_attr_ops,
};

static struct kset mlog_kset = {
	.kobj   = {.ktype = &mlog_ktype},
};

int mlog_sys_init(struct kset *o2cb_kset)
{
	int i = 0;

	while (mlog_attrs[i].attr.mode) {
		mlog_attr_ptrs[i] = &mlog_attrs[i].attr;
		i++;
	}
	mlog_attr_ptrs[i] = NULL;

	kobject_set_name(&mlog_kset.kobj, "logmask");
	mlog_kset.kobj.kset = o2cb_kset;
	return kset_register(&mlog_kset);
}

void mlog_sys_shutdown(void)
{
	kset_unregister(&mlog_kset);
}