mirror of
https://github.com/google/pebble.git
synced 2025-05-02 08:11:39 -04:00
44 lines
1.6 KiB
C
44 lines
1.6 KiB
C
/*
|
|
* Copyright 2024 Google LLC
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#include "cpu_cache.h"
|
|
#include "syscall/syscall_internal.h"
|
|
|
|
#include "mcu/cache.h"
|
|
|
|
DEFINE_SYSCALL(void, memory_cache_flush, void *start, size_t size) {
|
|
// We need to align the address and size properly for the cache functions. It needs to be done
|
|
// before we do syscall_assert_userspace_buffer though, because otherwise the user could
|
|
// potentially abuse this behavior to flush+invalidate kernel memory. Theoretically that
|
|
// shouldn't actually have any really effect, but it's better to be safe than sorry.
|
|
// That should only be possible if the user region is not cache aligned, so in any realistic
|
|
// case this won't even matter.
|
|
uintptr_t start_addr = (uintptr_t)start;
|
|
icache_align(&start_addr, &size);
|
|
dcache_align(&start_addr, &size);
|
|
start = (void *)start_addr;
|
|
|
|
if (PRIVILEGE_WAS_ELEVATED) {
|
|
syscall_assert_userspace_buffer(start, size);
|
|
}
|
|
|
|
if (dcache_is_enabled()) {
|
|
dcache_flush(start, size);
|
|
}
|
|
if (icache_is_enabled()) {
|
|
icache_invalidate(start, size);
|
|
}
|
|
}
|