Kernel: Implemented shared memory permissions.

This commit is contained in:
Subv 2016-04-17 21:58:51 -05:00
parent 9005cda664
commit 0fb6d2a247
4 changed files with 50 additions and 9 deletions

View file

@ -46,6 +46,7 @@ SharedPtr<SharedMemory> SharedMemory::Create(SharedPtr<Process> owner_process, u
Kernel::g_current_process->vm_manager.RefreshMemoryBlockMappings(linheap_memory.get());
}
} else {
// TODO(Subv): What happens if an application tries to create multiple memory blocks pointing to the same address?
auto& vm_manager = shared_memory->owner_process->vm_manager;
// The memory is already available and mapped in the owner process.
auto vma = vm_manager.FindVMA(address)->second;
@ -56,6 +57,8 @@ SharedPtr<SharedMemory> SharedMemory::Create(SharedPtr<Process> owner_process, u
vm_manager.UnmapRange(address, size);
// Map our own block into the address space
vm_manager.MapMemoryBlock(address, shared_memory->backing_block, 0, size, MemoryState::Shared);
// Reprotect the block with the new permissions
vm_manager.ReprotectRange(address, size, ConvertPermissions(permissions));
}
shared_memory->base_address = address;
@ -65,8 +68,28 @@ SharedPtr<SharedMemory> SharedMemory::Create(SharedPtr<Process> owner_process, u
ResultCode SharedMemory::Map(Process* target_process, VAddr address, MemoryPermission permissions,
MemoryPermission other_permissions) {
// TODO(Subv): Return E0E01BEE when permissions and other_permissions don't
// match what was specified when the memory block was created.
MemoryPermission own_other_permissions = target_process == owner_process ? this->permissions : this->other_permissions;
// Automatically allocated memory blocks can only be mapped with other_permissions = DontCare
if (base_address == 0 && other_permissions != MemoryPermission::DontCare) {
return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::OS, ErrorSummary::InvalidArgument, ErrorLevel::Usage);
}
// Error out if the requested permissions don't match what the creator process allows.
if (static_cast<u32>(permissions) & ~static_cast<u32>(own_other_permissions)) {
return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::OS, ErrorSummary::InvalidArgument, ErrorLevel::Usage);
}
// Heap-backed memory blocks can not be mapped with other_permissions = DontCare
if (base_address != 0 && other_permissions == MemoryPermission::DontCare) {
return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::OS, ErrorSummary::InvalidArgument, ErrorLevel::Usage);
}
// Error out if the provided permissions are not compatible with what the creator process needs.
if (other_permissions != MemoryPermission::DontCare &&
static_cast<u32>(this->permissions) & ~static_cast<u32>(other_permissions)) {
return ResultCode(ErrorDescription::WrongPermission, ErrorModule::OS, ErrorSummary::WrongArgument, ErrorLevel::Permanent);
}
// TODO(Subv): Check for the Shared Device Mem flag in the creator process.
/*if (was_created_with_shared_device_mem && address != 0) {
@ -76,12 +99,14 @@ ResultCode SharedMemory::Map(Process* target_process, VAddr address, MemoryPermi
// TODO(Subv): The same process that created a SharedMemory object
// can not map it in its own address space unless it was created with addr=0, result 0xD900182C.
if (address != 0) {
if (address < Memory::HEAP_VADDR || address + size >= Memory::SHARED_MEMORY_VADDR_END) {
LOG_ERROR(Kernel, "cannot map id=%u, address=0x%08X name=%s, invalid address",
GetObjectId(), address, name.c_str());
return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::OS,
ErrorSummary::InvalidArgument, ErrorLevel::Usage);
}
}
VAddr target_address = address;
@ -91,9 +116,11 @@ ResultCode SharedMemory::Map(Process* target_process, VAddr address, MemoryPermi
}
// Map the memory block into the target process
target_process->vm_manager.MapMemoryBlock(target_address, backing_block, backing_block_offset, size, MemoryState::Shared);
auto result = target_process->vm_manager.MapMemoryBlock(target_address, backing_block, backing_block_offset, size, MemoryState::Shared);
if (result.Failed())
return result.Code();
return RESULT_SUCCESS;
return target_process->vm_manager.ReprotectRange(target_address, size, ConvertPermissions(permissions));
}
ResultCode SharedMemory::Unmap(Process* target_process, VAddr address) {
@ -101,6 +128,11 @@ ResultCode SharedMemory::Unmap(Process* target_process, VAddr address) {
return target_process->vm_manager.UnmapRange(address, size);
}
VMAPermission SharedMemory::ConvertPermissions(MemoryPermission permission) {
u32 masked_permissions = static_cast<u32>(permission) & static_cast<u32>(MemoryPermission::ReadWriteExecute);
return static_cast<VMAPermission>(masked_permissions);
};
u8* SharedMemory::GetPointer(u32 offset) {
return backing_block->data() + backing_block_offset + offset;
}

View file

@ -48,6 +48,12 @@ public:
static const HandleType HANDLE_TYPE = HandleType::SharedMemory;
HandleType GetHandleType() const override { return HANDLE_TYPE; }
/**
* Converts the specified MemoryPermission into the equivalent VMAPermission.
* @param permission The MemoryPermission to convert.
*/
static VMAPermission ConvertPermissions(MemoryPermission permission);
/**
* Maps a shared memory block to an address in the target process' address space
* @param target_process Process on which to map the memory block.

View file

@ -17,6 +17,7 @@
/// Detailed description of the error. This listing is likely incomplete.
enum class ErrorDescription : u32 {
Success = 0,
WrongPermission = 46,
OS_InvalidBufferDescriptor = 48,
WrongAddress = 53,
FS_NotFound = 120,

View file

@ -99,6 +99,7 @@ static ResultCode ControlMemory(u32* out_addr, u32 operation, u32 addr0, u32 add
switch (operation & MEMOP_OPERATION_MASK) {
case MEMOP_FREE:
{
// TODO(Subv): What happens if an application tries to FREE a block of memory that has a SharedMemory pointing to it?
if (addr0 >= Memory::HEAP_VADDR && addr0 < Memory::HEAP_VADDR_END) {
ResultCode result = process.HeapFree(addr0, size);
if (result.IsError()) return result;
@ -798,6 +799,7 @@ static ResultCode CreateMemoryBlock(Handle* out_handle, u32 addr, u32 size, u32
case MemoryPermission::Read:
case MemoryPermission::Write:
case MemoryPermission::ReadWrite:
case MemoryPermission::DontCare:
return true;
default:
return false;