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/*
* Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
* 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.
*/
//#define STORAGE_DEVICE_DEBUG
#include <AK/Memory.h>
#include <AK/StringView.h>
#include <Kernel/FileSystem/FileDescription.h>
#include <Kernel/Storage/StorageDevice.h>
namespace Kernel {
StorageDevice::StorageDevice(const StorageController& controller, int major, int minor, size_t sector_size, size_t max_addressable_block)
: BlockDevice(major, minor, sector_size)
, m_storage_controller(controller)
, m_max_addressable_block(max_addressable_block)
{
}
const char* StorageDevice::class_name() const
{
return "StorageDevice";
}
NonnullRefPtr<StorageController> StorageDevice::controller() const
{
return m_storage_controller;
}
KResultOr<size_t> StorageDevice::read(FileDescription&, size_t offset, UserOrKernelBuffer& outbuf, size_t len)
{
unsigned index = offset / block_size();
u16 whole_blocks = len / block_size();
ssize_t remaining = len % block_size();
unsigned blocks_per_page = PAGE_SIZE / block_size();
// PATAChannel will chuck a wobbly if we try to read more than PAGE_SIZE
// at a time, because it uses a single page for its DMA buffer.
if (whole_blocks >= blocks_per_page) {
whole_blocks = blocks_per_page;
remaining = 0;
}
#ifdef STORAGE_DEVICE_DEBUG
klog() << "StorageDevice::read() index=" << index << " whole_blocks=" << whole_blocks << " remaining=" << remaining;
#endif
if (whole_blocks > 0) {
auto read_request = make_request<AsyncBlockDeviceRequest>(AsyncBlockDeviceRequest::Read, index, whole_blocks, outbuf, whole_blocks * block_size());
auto result = read_request->wait();
if (result.wait_result().was_interrupted())
return KResult(-EINTR);
switch (result.request_result()) {
case AsyncDeviceRequest::Failure:
case AsyncDeviceRequest::Cancelled:
return KResult(-EIO);
case AsyncDeviceRequest::MemoryFault:
return KResult(-EFAULT);
default:
break;
}
}
off_t pos = whole_blocks * block_size();
if (remaining > 0) {
auto data = ByteBuffer::create_uninitialized(block_size());
auto data_buffer = UserOrKernelBuffer::for_kernel_buffer(data.data());
auto read_request = make_request<AsyncBlockDeviceRequest>(AsyncBlockDeviceRequest::Read, index + whole_blocks, 1, data_buffer, block_size());
auto result = read_request->wait();
if (result.wait_result().was_interrupted())
return KResult(-EINTR);
switch (result.request_result()) {
case AsyncDeviceRequest::Failure:
return pos;
case AsyncDeviceRequest::Cancelled:
return KResult(-EIO);
case AsyncDeviceRequest::MemoryFault:
// This should never happen, we're writing to a kernel buffer!
ASSERT_NOT_REACHED();
default:
break;
}
if (!outbuf.write(data.data(), pos, remaining))
return KResult(-EFAULT);
}
return pos + remaining;
}
bool StorageDevice::can_read(const FileDescription&, size_t offset) const
{
return offset < (max_addressable_block() * block_size());
}
KResultOr<size_t> StorageDevice::write(FileDescription&, size_t offset, const UserOrKernelBuffer& inbuf, size_t len)
{
unsigned index = offset / block_size();
u16 whole_blocks = len / block_size();
ssize_t remaining = len % block_size();
unsigned blocks_per_page = PAGE_SIZE / block_size();
// PATAChannel will chuck a wobbly if we try to write more than PAGE_SIZE
// at a time, because it uses a single page for its DMA buffer.
if (whole_blocks >= blocks_per_page) {
whole_blocks = blocks_per_page;
remaining = 0;
}
#ifdef STORAGE_DEVICE_DEBUG
klog() << "StorageDevice::write() index=" << index << " whole_blocks=" << whole_blocks << " remaining=" << remaining;
#endif
if (whole_blocks > 0) {
auto write_request = make_request<AsyncBlockDeviceRequest>(AsyncBlockDeviceRequest::Write, index, whole_blocks, inbuf, whole_blocks * block_size());
auto result = write_request->wait();
if (result.wait_result().was_interrupted())
return KResult(-EINTR);
switch (result.request_result()) {
case AsyncDeviceRequest::Failure:
case AsyncDeviceRequest::Cancelled:
return KResult(-EIO);
case AsyncDeviceRequest::MemoryFault:
return KResult(-EFAULT);
default:
break;
}
}
off_t pos = whole_blocks * block_size();
// since we can only write in block_size() increments, if we want to do a
// partial write, we have to read the block's content first, modify it,
// then write the whole block back to the disk.
if (remaining > 0) {
auto data = ByteBuffer::create_zeroed(block_size());
auto data_buffer = UserOrKernelBuffer::for_kernel_buffer(data.data());
{
auto read_request = make_request<AsyncBlockDeviceRequest>(AsyncBlockDeviceRequest::Read, index + whole_blocks, 1, data_buffer, block_size());
auto result = read_request->wait();
if (result.wait_result().was_interrupted())
return KResult(-EINTR);
switch (result.request_result()) {
case AsyncDeviceRequest::Failure:
return pos;
case AsyncDeviceRequest::Cancelled:
return KResult(-EIO);
case AsyncDeviceRequest::MemoryFault:
// This should never happen, we're writing to a kernel buffer!
ASSERT_NOT_REACHED();
default:
break;
}
}
if (!inbuf.read(data.data(), pos, remaining))
return KResult(-EFAULT);
{
auto write_request = make_request<AsyncBlockDeviceRequest>(AsyncBlockDeviceRequest::Write, index + whole_blocks, 1, data_buffer, block_size());
auto result = write_request->wait();
if (result.wait_result().was_interrupted())
return KResult(-EINTR);
switch (result.request_result()) {
case AsyncDeviceRequest::Failure:
return pos;
case AsyncDeviceRequest::Cancelled:
return KResult(-EIO);
case AsyncDeviceRequest::MemoryFault:
// This should never happen, we're writing to a kernel buffer!
ASSERT_NOT_REACHED();
default:
break;
}
}
}
return pos + remaining;
}
bool StorageDevice::can_write(const FileDescription&, size_t offset) const
{
return offset < (max_addressable_block() * block_size());
}
}
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