yuzu/src/core/hle/kernel/process_capability.h
Lioncash 27caf71204 kernel/process_capability: Handle the priority mask and core mask flags
Handles the priority mask and core mask flags to allow building up the
masks to determine the usable thread priorities and cores for a kernel
process instance.
2018-12-21 07:05:34 -05:00

220 lines
8.9 KiB
C++

// Copyright 2018 yuzu emulator team
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <bitset>
#include "common/common_types.h"
union ResultCode;
namespace Kernel {
class VMManager;
/// Handles kernel capability descriptors that are provided by
/// application metadata. These descriptors provide information
/// that alters certain parameters for kernel process instance
/// that will run said application (or applet).
///
/// Capabilities are a sequence of flag descriptors, that indicate various
/// configurations and constraints for a particular process.
///
/// Flag types are indicated by a sequence of set low bits. E.g. the
/// types are indicated with the low bits as follows (where x indicates "don't care"):
///
/// - Priority and core mask : 0bxxxxxxxxxxxx0111
/// - Allowed service call mask: 0bxxxxxxxxxxx01111
/// - Map physical memory : 0bxxxxxxxxx0111111
/// - Map IO memory : 0bxxxxxxxx01111111
/// - Interrupts : 0bxxxx011111111111
/// - Application type : 0bxx01111111111111
/// - Kernel version : 0bx011111111111111
/// - Handle table size : 0b0111111111111111
/// - Debugger flags : 0b1111111111111111
///
/// These are essentially a bit offset subtracted by 1 to create a mask.
/// e.g. The first entry in the above list is simply bit 3 (value 8 -> 0b1000)
/// subtracted by one (7 -> 0b0111)
///
/// An example of a bit layout (using the map physical layout):
/// <example>
/// The MapPhysical type indicates a sequence entry pair of:
///
/// [initial, memory_flags], where:
///
/// initial:
/// bits:
/// 7-24: Starting page to map memory at.
/// 25 : Indicates if the memory should be mapped as read only.
///
/// memory_flags:
/// bits:
/// 7-20 : Number of pages to map
/// 21-25: Seems to be reserved (still checked against though)
/// 26 : Whether or not the memory being mapped is IO memory, or physical memory
/// </example>
///
class ProcessCapabilities {
public:
using InterruptCapabilities = std::bitset<1024>;
using SyscallCapabilities = std::bitset<128>;
ProcessCapabilities() = default;
ProcessCapabilities(const ProcessCapabilities&) = delete;
ProcessCapabilities(ProcessCapabilities&&) = default;
ProcessCapabilities& operator=(const ProcessCapabilities&) = delete;
ProcessCapabilities& operator=(ProcessCapabilities&&) = default;
/// Initializes this process capabilities instance for a kernel process.
///
/// @param capabilities The capabilities to parse
/// @param num_capabilities The number of capabilities to parse.
/// @param vm_manager The memory manager to use for handling any mapping-related
/// operations (such as mapping IO memory, etc).
///
/// @returns RESULT_SUCCESS if this capabilities instance was able to be initialized,
/// otherwise, an error code upon failure.
///
ResultCode InitializeForKernelProcess(const u32* capabilities, std::size_t num_capabilities,
VMManager& vm_manager);
/// Initializes this process capabilities instance for a userland process.
///
/// @param capabilities The capabilities to parse.
/// @param num_capabilities The total number of capabilities to parse.
/// @param vm_manager The memory manager to use for handling any mapping-related
/// operations (such as mapping IO memory, etc).
///
/// @returns RESULT_SUCCESS if this capabilities instance was able to be initialized,
/// otherwise, an error code upon failure.
///
ResultCode InitializeForUserProcess(const u32* capabilities, std::size_t num_capabilities,
VMManager& vm_manager);
/// Initializes this process capabilities instance for a process that does not
/// have any metadata to parse.
///
/// This is necessary, as we allow running raw executables, and the internal
/// kernel process capabilities also determine what CPU cores the process is
/// allowed to run on, and what priorities are allowed for threads. It also
/// determines the max handle table size, what the program type is, whether or
/// not the process can be debugged, or whether it's possible for a process to
/// forcibly debug another process.
///
/// Given the above, this essentially enables all capabilities across the board
/// for the process. It allows the process to:
///
/// - Run on any core
/// - Use any thread priority
/// - Use the maximum amount of handles a process is allowed to.
/// - Be debuggable
/// - Forcibly debug other processes.
///
/// Note that this is not a behavior that the kernel allows a process to do via
/// a single function like this. This is yuzu-specific behavior to handle
/// executables with no capability descriptors whatsoever to derive behavior from.
/// It being yuzu-specific is why this is also not the default behavior and not
/// done by default in the constructor.
///
void InitializeForMetadatalessProcess();
/// Gets the allowable core mask
u64 GetCoreMask() const {
return core_mask;
}
/// Gets the allowable priority mask
u64 GetPriorityMask() const {
return priority_mask;
}
private:
/// Attempts to parse a given sequence of capability descriptors.
///
/// @param capabilities The sequence of capability descriptors to parse.
/// @param num_capabilities The number of descriptors within the given sequence.
/// @param vm_manager The memory manager that will perform any memory
/// mapping if necessary.
///
/// @return RESULT_SUCCESS if no errors occur, otherwise an error code.
///
ResultCode ParseCapabilities(const u32* capabilities, std::size_t num_capabilities,
VMManager& vm_manager);
/// Attempts to parse a capability descriptor that is only represented by a
/// single flag set.
///
/// @param set_flags Running set of flags that are used to catch
/// flags being initialized more than once when they shouldn't be.
/// @param set_svc_bits Running set of bits representing the allowed supervisor calls mask.
/// @param flag The flag to attempt to parse.
/// @param vm_manager The memory manager that will perform any memory
/// mapping if necessary.
///
/// @return RESULT_SUCCESS if no errors occurred, otherwise an error code.
///
ResultCode ParseSingleFlagCapability(u32& set_flags, u32& set_svc_bits, u32 flag,
VMManager& vm_manager);
/// Clears the internal state of this process capability instance. Necessary,
/// to have a sane starting point due to us allowing running executables without
/// configuration metadata. We assume a process is not going to have metadata,
/// and if it turns out that the process does, in fact, have metadata, then
/// we attempt to parse it. Thus, we need this to reset data members back to
/// a good state.
///
/// DO NOT ever make this a public member function. This isn't an invariant
/// anything external should depend upon (and if anything comes to rely on it,
/// you should immediately be questioning the design of that thing, not this
/// class. If the kernel itself can run without depending on behavior like that,
/// then so can yuzu).
///
void Clear();
/// Handles flags related to the priority and core number capability flags.
ResultCode HandlePriorityCoreNumFlags(u32 flags);
/// Handles flags related to determining the allowable SVC mask.
ResultCode HandleSyscallFlags(u32& set_svc_bits, u32 flags);
/// Handles flags related to mapping physical memory pages.
ResultCode HandleMapPhysicalFlags(u32 flags, u32 size_flags, VMManager& vm_manager);
/// Handles flags related to mapping IO pages.
ResultCode HandleMapIOFlags(u32 flags, VMManager& vm_manager);
/// Handles flags related to the interrupt capability flags.
ResultCode HandleInterruptFlags(u32 flags);
/// Handles flags related to the program type.
ResultCode HandleProgramTypeFlags(u32 flags);
/// Handles flags related to the handle table size.
ResultCode HandleHandleTableFlags(u32 flags);
/// Handles flags related to the kernel version capability flags.
ResultCode HandleKernelVersionFlags(u32 flags);
/// Handles flags related to debug-specific capabilities.
ResultCode HandleDebugFlags(u32 flags);
SyscallCapabilities svc_capabilities;
InterruptCapabilities interrupt_capabilities;
u64 core_mask = 0;
u64 priority_mask = 0;
u32 handle_table_size = 0;
u32 kernel_version = 0;
u32 program_type = 0;
bool is_debuggable = false;
bool can_force_debug = false;
};
} // namespace Kernel