mars/kernel/brick_checking.h

/*
 * MARS Long Distance Replication Software
 *
 * This file is part of MARS project: http://schoebel.github.io/mars/
 *
 * Copyright (C) 2010-2014 Thomas Schoebel-Theuer
 * Copyright (C) 2011-2014 1&1 Internet AG
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef BRICK_CHECKING_H
#define BRICK_CHECKING_H

/////////////////////////////////////////////////////////////////////////

// checking

#if defined(CONFIG_MARS_DEBUG) || defined(CONFIG_MARS_CHECKS)
#define BRICK_CHECKING true
#else
#define BRICK_CHECKING false
#endif

#define _CHECK_ATOMIC(atom,OP,minval)					\
do {									\
	if (BRICK_CHECKING) {						\
		int __test = atomic_read(atom);				\
		if (unlikely(__test OP (minval))) {			\
			atomic_set(atom, minval);			\
			BRICK_ERR("%d: atomic " #atom " " #OP " " #minval " (%d)\n", __LINE__, __test); \
		}							\
	}								\
} while (0)

#define CHECK_ATOMIC(atom,minval)		\
	_CHECK_ATOMIC(atom, <, minval)

#define CHECK_HEAD_EMPTY(head)						\
do {									\
	if (BRICK_CHECKING &&						\
	    unlikely(!list_empty(head) &&				\
		     (head)->next &&					\
		     (head)->next != LIST_POISON1 &&			\
		     (head)->prev != LIST_POISON2)) {			\
		list_del_init(head);					\
		BRICK_ERR("%d: list_head " #head " (%p) not empty\n", __LINE__, head); \
	}								\
} while (0)

#ifdef CONFIG_MARS_DEBUG_MEM
#define CHECK_PTR_DEAD(ptr,label)					\
do {									\
	if (BRICK_CHECKING &&						\
	    unlikely(							\
		((unsigned long)(ptr) & 0xffffffff) == 0x5a5a5a5a ||	\
		((unsigned long)(ptr) & 0xffffffff) == 0x6b6b6b6b)) {	\
		BRICK_FAT("%d: pointer '" #ptr "' is DEAD\n", __LINE__); \
		goto label;						\
	}								\
} while (0)
#else
#define CHECK_PTR_DEAD(ptr,label) /*empty*/
#endif

/* Counterpart of CHECK_PTR_NULL().
 * Most of the consequences should be caught by the compiler,
 * without producing code (potentially except some debugging code).
 * Otherwise, or when dump_stack()ing at runtime, code inspection should be
 * tightened.
 * So this is essentially a self-check against common bugs, often introduced
 * during reorgs.
 */
#ifdef BRICK_CHECKING
#define SET_PTR_NULL(ptr) (ptr) = NULL
#else
#define SET_PTR_NULL(ptr) /* empty */
#endif

#define CHECK_PTR_NULL(ptr,label)					\
do {									\
	CHECK_PTR_DEAD(ptr, label);					\
	if (BRICK_CHECKING && unlikely(!(ptr))) {		        \
		BRICK_FAT("%d: pointer '" #ptr "' is NULL\n", __LINE__); \
		goto label;						\
	}								\
} while (0)

#ifdef CONFIG_MARS_DEBUG
#define CHECK_PTR(ptr,label)						\
do {									\
	CHECK_PTR_NULL(ptr, label);					\
	if (BRICK_CHECKING && unlikely(!virt_addr_valid(ptr))) {	\
		BRICK_FAT("%d: pointer '" #ptr "' (%p) is no valid virtual KERNEL address\n", __LINE__, ptr); \
		goto label;						\
	}								\
} while (0)
#else
#define CHECK_PTR(ptr,label) CHECK_PTR_NULL(ptr,label)
#endif

#define CHECK_ASPECT(a_ptr, o_ptr,label)				\
  do {								        \
	  if (BRICK_CHECKING && unlikely((a_ptr)->object != o_ptr)) {	\
		  BRICK_FAT("%d: aspect pointer '" #a_ptr "' (%p) belongs to object %p, not to " #o_ptr " (%p)\n", __LINE__, a_ptr, (a_ptr)->object, o_ptr); \
		  goto label;						\
	  }								\
} while (0)

#define _CHECK(ptr,label)						\
do {									\
	if (BRICK_CHECKING && unlikely(!(ptr))) {			\
		BRICK_FAT("%d: condition '" #ptr "' is VIOLATED\n", __LINE__); \
		goto label;						\
	}								\
} while (0)

#endif