mirror of
https://github.com/RGBCube/serenity
synced 2025-05-28 08:45:09 +00:00
ecfa7cb824
This patch allocates a physical page for each of the virtqueues and memcpys to it when receiving a buffer to get a physical, aligned contiguous buffer as required by the virtio specification. Co-authored-by: Sahan <sahan.h.fernando@gmail.com>
106 lines
3.8 KiB
C++
106 lines
3.8 KiB
C++
/*
|
|
* Copyright (c) 2020, the SerenityOS developers.
|
|
* 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/StdLib.h>
|
|
#include <Kernel/VirtIO/VirtIOQueue.h>
|
|
|
|
namespace Kernel {
|
|
|
|
VirtIOQueue::VirtIOQueue(u16 queue_size, u16 notify_offset)
|
|
: m_queue_size(queue_size)
|
|
, m_notify_offset(notify_offset)
|
|
, m_free_buffers(queue_size)
|
|
{
|
|
size_t size_of_descriptors = sizeof(VirtIOQueueDescriptor) * queue_size;
|
|
size_t size_of_driver = sizeof(VirtIOQueueDriver) + queue_size * sizeof(u16);
|
|
size_t size_of_device = sizeof(VirtIOQueueDevice) + queue_size * sizeof(VirtIOQueueDeviceItem);
|
|
m_region = MM.allocate_contiguous_kernel_region(page_round_up(size_of_descriptors + size_of_driver + size_of_device), "VirtIO Queue", Region::Access::Read | Region::Access::Write);
|
|
if (m_region) {
|
|
// TODO: ensure alignment!!!
|
|
u8* ptr = m_region->vaddr().as_ptr();
|
|
memset(ptr, 0, m_region->size());
|
|
m_descriptors = reinterpret_cast<VirtIOQueueDescriptor*>(ptr);
|
|
m_driver = reinterpret_cast<VirtIOQueueDriver*>(ptr + size_of_descriptors);
|
|
m_device = reinterpret_cast<VirtIOQueueDevice*>(ptr + size_of_descriptors + size_of_driver);
|
|
|
|
enable_interrupts();
|
|
}
|
|
}
|
|
|
|
VirtIOQueue::~VirtIOQueue()
|
|
{
|
|
}
|
|
|
|
void VirtIOQueue::enable_interrupts()
|
|
{
|
|
m_driver->flags = 0;
|
|
}
|
|
|
|
void VirtIOQueue::disable_interrupts()
|
|
{
|
|
m_driver->flags = 1;
|
|
}
|
|
|
|
bool VirtIOQueue::supply_buffer(Badge<VirtIODevice>, const u8* buffer, u32 length, BufferType buffer_type)
|
|
{
|
|
VERIFY(buffer && length > 0);
|
|
VERIFY(m_free_buffers > 0);
|
|
|
|
auto descriptor_index = m_free_head;
|
|
m_descriptors[descriptor_index].flags = static_cast<u16>(buffer_type);
|
|
m_descriptors[descriptor_index].address = reinterpret_cast<u64>(buffer);
|
|
m_descriptors[descriptor_index].length = length;
|
|
|
|
m_free_buffers--;
|
|
m_free_head = (m_free_head + 1) % m_queue_size;
|
|
|
|
m_driver->rings[m_driver_index_shadow % m_queue_size] = descriptor_index; // m_driver_index_shadow is used to prevent accesses to index before the rings are updated
|
|
|
|
full_memory_barrier();
|
|
|
|
m_driver_index_shadow++;
|
|
m_driver->index++;
|
|
|
|
full_memory_barrier();
|
|
|
|
auto device_flags = m_device->flags;
|
|
return !(device_flags & 1); // if bit 1 is enabled the device disabled interrupts
|
|
}
|
|
bool VirtIOQueue::new_data_available() const
|
|
{
|
|
return m_device->index != m_used_tail;
|
|
}
|
|
bool VirtIOQueue::handle_interrupt()
|
|
{
|
|
if (!new_data_available())
|
|
return false;
|
|
|
|
if (on_data_available)
|
|
on_data_available();
|
|
return true;
|
|
}
|
|
|
|
}
|