ladybird/Kernel/Devices/MBVGADevice.cpp
Andreas Kling f1b5def8fd Kernel: Factor address space management out of the Process class
This patch adds Space, a class representing a process's address space.

- Each Process has a Space.
- The Space owns the PageDirectory and all Regions in the Process.

This allows us to reorganize sys$execve() so that it constructs and
populates a new Space fully before committing to it.

Previously, we would construct the new address space while still
running in the old one, and encountering an error meant we had to do
tedious and error-prone rollback.

Those problems are now gone, replaced by what's hopefully a set of much
smaller problems and missing cleanups. :^)
2021-02-08 18:27:28 +01:00

124 lines
4.1 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;
if (offset != 0)
return ENXIO;
if (range.size() != PAGE_ROUND_UP(framebuffer_size_in_bytes()))
return EOVERFLOW;
auto vmobject = AnonymousVMObject::create_for_physical_range(m_framebuffer_address, framebuffer_size_in_bytes());
if (!vmobject)
return ENOMEM;
return process.space().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());
}
}