ladybird/Kernel/Heap/kmalloc.h
Andreas Kling c1f74bf327 Kernel: Never validate access to the kmalloc memory range
Memory validation is used to verify that user syscalls are allowed to
access a given memory range. Ring 0 threads never make syscalls, and
so will never end up in validation anyway.

The reason we were allowing kmalloc memory accesses is because kernel
thread stacks used to be allocated in kmalloc memory. Since that's no
longer the case, we can stop making exceptions for kmalloc in the
validation code.
2020-01-27 12:43:21 +01:00

61 lines
2.5 KiB
C

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/Types.h>
//#define KMALLOC_DEBUG_LARGE_ALLOCATIONS
void kmalloc_init();
[[gnu::malloc, gnu::returns_nonnull, gnu::alloc_size(1)]] void* kmalloc_impl(size_t);
[[gnu::malloc, gnu::returns_nonnull, gnu::alloc_size(1)]] void* kmalloc_eternal(size_t);
[[gnu::malloc, gnu::returns_nonnull, gnu::alloc_size(1)]] void* kmalloc_page_aligned(size_t);
[[gnu::malloc, gnu::returns_nonnull, gnu::alloc_size(1)]] void* kmalloc_aligned(size_t, size_t alignment);
void* krealloc(void*, size_t);
void kfree(void*);
void kfree_aligned(void*);
extern volatile size_t sum_alloc;
extern volatile size_t sum_free;
extern volatile size_t kmalloc_sum_eternal;
extern volatile size_t kmalloc_sum_page_aligned;
extern u32 g_kmalloc_call_count;
extern u32 g_kfree_call_count;
extern bool g_dump_kmalloc_stacks;
inline void* operator new(size_t, void* p) { return p; }
inline void* operator new[](size_t, void* p) { return p; }
[[gnu::always_inline]] inline void* kmalloc(size_t size)
{
#ifdef KMALLOC_DEBUG_LARGE_ALLOCATIONS
// Any kernel allocation >= 1M is 99.9% a bug.
if (size >= 1048576)
asm volatile("cli;hlt");
#endif
return kmalloc_impl(size);
}