list_debug.c

Go to the documentation of this file.

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2022 - Google LLC
 * Author: Keir Fraser <keirf@google.com>
 */
 
#include <linux/list.h>
#include <linux/bug.h>
 
static inline __must_check bool nvhe_check_data_corruption(bool v)
{
    return v;
}
 
#define NVHE_CHECK_DATA_CORRUPTION(condition)                \
    nvhe_check_data_corruption(({                    \
        bool corruption = unlikely(condition);           \
        if (corruption) {                    \
            if (IS_ENABLED(CONFIG_BUG_ON_DATA_CORRUPTION)) { \
                BUG_ON(1);               \
            } else                       \
                WARN_ON(1);              \
        }                            \
        corruption;                      \
    }))
 
/* The predicates checked here are taken from lib/list_debug.c. */
 
__list_valid_slowpath
bool __list_add_valid_or_report(struct list_head *new, struct list_head *prev,
                struct list_head *next)
{
    if (NVHE_CHECK_DATA_CORRUPTION(next->prev != prev) ||
        NVHE_CHECK_DATA_CORRUPTION(prev->next != next) ||
        NVHE_CHECK_DATA_CORRUPTION(new == prev || new == next))
        return false;
 
    return true;
}
 
__list_valid_slowpath
bool __list_del_entry_valid_or_report(struct list_head *entry)
{
    struct list_head *prev, *next;
 
    prev = entry->prev;
    next = entry->next;
 
    if (NVHE_CHECK_DATA_CORRUPTION(next == LIST_POISON1) ||
        NVHE_CHECK_DATA_CORRUPTION(prev == LIST_POISON2) ||
        NVHE_CHECK_DATA_CORRUPTION(prev->next != entry) ||
        NVHE_CHECK_DATA_CORRUPTION(next->prev != entry))
        return false;
 
    return true;
}