ladybird/Kernel/Devices/MBVGADevice.cpp
Andreas Kling ab14b0ac64 Kernel: Hoist VM range allocation up to sys$mmap() itself
Instead of letting each File subclass do range allocation in their
mmap() override, do it up front in sys$mmap().

This makes us honor alignment requests for file-backed memory mappings
and simplifies the code somwhat.
2021-01-25 18:57:06 +01:00

122 lines
4.0 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.
*/
#include <Kernel/Devices/MBVGADevice.h>
#include <Kernel/Process.h>
#include <Kernel/VM/AnonymousVMObject.h>
#include <Kernel/VM/MemoryManager.h>
#include <LibC/errno_numbers.h>
#include <LibC/sys/ioctl_numbers.h>
namespace Kernel {
static MBVGADevice* s_the;
MBVGADevice& MBVGADevice::the()
{
return *s_the;
}
MBVGADevice::MBVGADevice(PhysicalAddress addr, size_t pitch, size_t width, size_t height)
: BlockDevice(29, 0)
, m_framebuffer_address(addr)
, m_framebuffer_pitch(pitch)
, m_framebuffer_width(width)
, m_framebuffer_height(height)
{
dbgln("MBVGADevice address={}, pitch={}, width={}, height={}", addr, pitch, width, height);
s_the = this;
}
KResultOr<Region*> MBVGADevice::mmap(Process& process, FileDescription&, const Range& range, size_t offset, int prot, bool shared)
{
REQUIRE_PROMISE(video);
if (!shared)
return ENODEV;
ASSERT(offset == 0);
ASSERT(range.size() == framebuffer_size_in_bytes());
auto vmobject = AnonymousVMObject::create_for_physical_range(m_framebuffer_address, framebuffer_size_in_bytes());
if (!vmobject)
return ENOMEM;
return process.allocate_region_with_vmobject(
range,
vmobject.release_nonnull(),
0,
"MBVGA Framebuffer",
prot,
shared);
}
int MBVGADevice::ioctl(FileDescription&, unsigned request, FlatPtr arg)
{
REQUIRE_PROMISE(video);
switch (request) {
case FB_IOCTL_GET_SIZE_IN_BYTES: {
auto* out = (size_t*)arg;
size_t value = framebuffer_size_in_bytes();
if (!copy_to_user(out, &value))
return -EFAULT;
return 0;
}
case FB_IOCTL_GET_BUFFER: {
auto* index = (int*)arg;
int value = 0;
if (!copy_to_user(index, &value))
return -EFAULT;
return 0;
}
case FB_IOCTL_GET_RESOLUTION: {
auto* user_resolution = (FBResolution*)arg;
FBResolution resolution;
resolution.pitch = m_framebuffer_pitch;
resolution.width = m_framebuffer_width;
resolution.height = m_framebuffer_height;
if (!copy_to_user(user_resolution, &resolution))
return -EFAULT;
return 0;
}
case FB_IOCTL_SET_RESOLUTION: {
auto* user_resolution = (FBResolution*)arg;
FBResolution resolution;
resolution.pitch = m_framebuffer_pitch;
resolution.width = m_framebuffer_width;
resolution.height = m_framebuffer_height;
if (!copy_to_user(user_resolution, &resolution))
return -EFAULT;
return 0;
}
default:
return -EINVAL;
};
}
String MBVGADevice::device_name() const
{
return String::formatted("fb{}", minor());
}
}