LLE Mapped Buffer: Add unmapping, zero-size, and multiple page handling

This commit is contained in:
NarcolepticK 2018-09-11 14:34:18 -04:00
parent 9f972b9f5c
commit 19291ba465
2 changed files with 40 additions and 12 deletions

View File

@ -128,7 +128,11 @@ ResultCode TranslateCommandBuffer(SharedPtr<Thread> src_thread, SharedPtr<Thread
u32 num_pages =
Common::AlignUp(page_offset + size, Memory::PAGE_SIZE) >> Memory::PAGE_BITS;
ASSERT(num_pages >= 1);
// Skip when the size is zero
if (size == 0) {
i += 1;
break;
}
if (reply) {
// TODO(Subv): Scan the target's command buffer to make sure that there was a
@ -139,13 +143,23 @@ ResultCode TranslateCommandBuffer(SharedPtr<Thread> src_thread, SharedPtr<Thread
// process again because they were (presumably) not modified. This behavior is
// consistent with the real kernel.
if (permissions == IPC::MappedBufferPermissions::R) {
ResultCode result = src_process->vm_manager.UnmapRange(
page_start, num_pages * Memory::PAGE_SIZE);
ASSERT(result == RESULT_SUCCESS);
} else {
const auto vma_iter = src_process->vm_manager.vma_map.find(source_address);
const auto& vma = vma_iter->second;
const VAddr dest_address = vma.originating_buffer_address;
auto buffer = std::make_shared<std::vector<u8>>(size);
Memory::ReadBlock(*src_process, source_address, buffer->data(), size);
Memory::WriteBlock(*dst_process, dest_address, buffer->data(), size);
ResultCode result = src_process->vm_manager.UnmapRange(
page_start, num_pages * Memory::PAGE_SIZE);
ASSERT(result == RESULT_SUCCESS);
}
ASSERT_MSG(permissions == IPC::MappedBufferPermissions::R,
"Unmapping Write MappedBuffers is unimplemented");
i += 1;
break;
}
@ -156,19 +170,13 @@ ResultCode TranslateCommandBuffer(SharedPtr<Thread> src_thread, SharedPtr<Thread
return (address & Memory::PAGE_MASK) == 0;
};
// TODO(Subv): Support more than 1 page and aligned page mappings
ASSERT_MSG(
num_pages == 1 &&
(!IsPageAligned(source_address) || !IsPageAligned(source_address + size)),
"MappedBuffers of more than one page or aligned transfers are not implemented");
// TODO(Subv): Perform permission checks.
// TODO(Subv): Leave a page of Reserved memory before the first page and after the last
// TODO(Subv): Leave a page of unmapped memory before the first page and after the last
// page.
if (!IsPageAligned(source_address) ||
(num_pages == 1 && !IsPageAligned(source_address + size))) {
if (num_pages == 1 && !IsPageAligned(source_address) &&
!IsPageAligned(source_address + size)) {
// If the address of the source buffer is not page-aligned or if the buffer doesn't
// fill an entire page, then we have to allocate a page of memory in the target
// process and copy over the data from the input buffer. This allocated buffer will
@ -195,7 +203,24 @@ ResultCode TranslateCommandBuffer(SharedPtr<Thread> src_thread, SharedPtr<Thread
buffer, 0, static_cast<u32>(buffer->size()),
Kernel::MemoryState::Shared)
.Unwrap();
} else {
auto buffer = std::make_shared<std::vector<u8>>(num_pages * Memory::PAGE_SIZE);
Memory::ReadBlock(*src_process, source_address, buffer->data() + page_offset, size);
// Map the pages into the target process' address space.
target_address =
dst_process->vm_manager
.MapMemoryBlockToBase(Memory::IPC_MAPPING_VADDR + Memory::PAGE_SIZE,
Memory::IPC_MAPPING_SIZE - Memory::PAGE_SIZE, buffer,
0, static_cast<u32>(buffer->size()),
Kernel::MemoryState::Shared)
.Unwrap();
}
// Save the original address we copied the buffer from so that we can copy the modified
// buffer back, if needed
auto vma_iter = dst_process->vm_manager.vma_map.find(target_address + page_offset);
auto& vma = vma_iter->second;
vma.originating_buffer_address = source_address;
cmd_buf[i++] = target_address + page_offset;
break;

View File

@ -86,6 +86,9 @@ struct VirtualMemoryArea {
PAddr paddr = 0;
Memory::MMIORegionPointer mmio_handler = nullptr;
/// Originating address of the IPC mapped buffer
VAddr originating_buffer_address = 0;
/// Tests if this area can be merged to the right with `next`.
bool CanBeMergedWith(const VirtualMemoryArea& next) const;
};