Rework the nvdrv core for accuracy and support new deserialisation

Devices will need to be moved over in order to support this new
interface, IOCTL2/3 support will be added in a later commit.

app/src/main/cpp/skyline/services/nvdrv/INvDrvServices.cpp

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: MPL-2.0
+// SPDX-License-Identifier: MIT OR MPL-2.0
 // Copyright © 2020 Skyline Team and Contributors (https://github.com/skyline-emu/)
 
 #include <kernel/types/KProcess.h>
@@ -6,72 +6,72 @@
 #include "driver.h"
 #include "devices/nvdevice.h"
 
+#define NVRESULT(x) [&response](NvResult err) { response.Push<NvResult>(err); return Result{}; }(x)
+
 namespace skyline::service::nvdrv {
-    INvDrvServices::INvDrvServices(const DeviceState &state, ServiceManager &manager) : driver(nvdrv::driver.expired() ? std::make_shared<Driver>(state) : nvdrv::driver.lock()), BaseService(state, manager) {
-        if (nvdrv::driver.expired())
-            nvdrv::driver = driver;
-    }
+    INvDrvServices::INvDrvServices(const DeviceState &state, ServiceManager &manager, Driver &driver, const SessionPermissions &perms) : BaseService(state, manager), driver(driver), ctx(SessionContext{.perms = perms}) {}
 
     Result INvDrvServices::Open(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
-        auto path{request.inputBuf.at(0).as_string()};
+        constexpr FileDescriptor SessionFdLimit{sizeof(u64) * 2 * 8}; //!< Nvdrv uses two 64 bit variables to store a bitset
 
-        response.Push<u32>(driver->OpenDevice(path));
-        response.Push(device::NvStatus::Success);
+        auto path{request.inputBuf.at(0).as_string(true)};
+        if (path.empty() || nextFdIndex == SessionFdLimit) {
+            response.Push<FileDescriptor>(InvalidFileDescriptor);
+            return NVRESULT(NvResult::FileOperationFailed);
+        }
 
-        return {};
+        if (auto err{driver.OpenDevice(path, nextFdIndex, ctx)}; err != NvResult::Success) {
+            response.Push<FileDescriptor>(InvalidFileDescriptor);
+            return NVRESULT(err);
+        }
+
+        response.Push(nextFdIndex++);
+        return NVRESULT(NvResult::Success);
     }
 
     Result INvDrvServices::Ioctl(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
-        auto fd{request.Pop<u32>()};
-        auto cmd{request.Pop<u32>()};
+        auto fd{request.Pop<FileDescriptor>()};
+        auto ioctl{request.Pop<IoctlDescriptor>()};
 
-        auto device{driver->GetDevice(fd)};
+        auto inBuf{request.inputBuf.at(0)};
+        auto outBuf{request.outputBuf.at(0)};
 
-        // Strip the permissions from the command leaving only the ID
-        cmd &= 0xFFFF;
+        if (ioctl.in && inBuf.size() < ioctl.size)
+            return NVRESULT(NvResult::InvalidSize);
 
-        span<u8> buffer{};
-        if (request.inputBuf.empty() || request.outputBuf.empty()) {
-            if (!request.inputBuf.empty())
-                buffer = request.inputBuf.at(0);
-            else if (!request.outputBuf.empty())
-                buffer = request.outputBuf.at(0);
-            else
-                throw exception("No IOCTL Buffers");
-        } else if (request.inputBuf[0].data() == request.outputBuf[0].data()) {
-            if (request.inputBuf[0].size() >= request.outputBuf[0].size())
-                buffer = request.inputBuf[0];
-            else
-                buffer = request.outputBuf[0];
-        } else {
-            throw exception("IOCTL Input Buffer (0x{:X}) != Output Buffer (0x{:X})", request.inputBuf[0].data(), request.outputBuf[0].data());
+        if (ioctl.out && outBuf.size() < ioctl.size)
+            return NVRESULT(NvResult::InvalidSize);
+
+        if (ioctl.in && ioctl.out) {
+            if (outBuf.size() < inBuf.size())
+                return NVRESULT(NvResult::InvalidSize);
+
+            // Copy in buf to out buf for inout ioctls to avoid needing to pass around two buffers everywhere
+            if (outBuf.data() != inBuf.data())
+                outBuf.copy_from(inBuf, ioctl.size);
         }
 
-        response.Push(device->HandleIoctl(cmd, device::IoctlType::Ioctl, buffer, {}));
-        return {};
+        return NVRESULT(driver.Ioctl(fd, ioctl, ioctl.out ? outBuf : inBuf));
     }
 
     Result INvDrvServices::Close(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
         auto fd{request.Pop<u32>()};
         state.logger->Debug("Closing NVDRV device ({})", fd);
 
-        driver->CloseDevice(fd);
+        driver.CloseDevice(fd);
 
-        response.Push(device::NvStatus::Success);
-        return {};
+        return NVRESULT(NvResult::Success);
     }
 
     Result INvDrvServices::Initialize(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
-        response.Push(device::NvStatus::Success);
-        return {};
+        return NVRESULT(NvResult::Success);
     }
 
     Result INvDrvServices::QueryEvent(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
         auto fd{request.Pop<u32>()};
         auto eventId{request.Pop<u32>()};
 
-        auto device{driver->GetDevice(fd)};
-        auto event{device->QueryEvent(eventId)};
+        auto event{driver.QueryEvent(fd, eventId)};
 
         if (event != nullptr) {
             auto handle{state.process->InsertItem<type::KEvent>(event)};
@@ -79,70 +79,16 @@ namespace skyline::service::nvdrv {
             state.logger->Debug("FD: {}, Event ID: {}, Handle: 0x{:X}", fd, eventId, handle);
             response.copyHandles.push_back(handle);
 
-            response.Push(device::NvStatus::Success);
+            return NVRESULT(NvResult::Success);
         } else {
-            response.Push(device::NvStatus::BadValue);
+            return NVRESULT(NvResult::BadValue);
         }
-
-        return {};
     }
 
     Result INvDrvServices::SetAruid(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
-        response.Push(device::NvStatus::Success);
-        return {};
+        return NVRESULT(NvResult::Success);
     }
 
-    Result INvDrvServices::Ioctl2(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
-        auto fd{request.Pop<u32>()};
-        auto cmd{request.Pop<u32>()};
-
-        auto device{driver->GetDevice(fd)};
-
-        // Strip the permissions from the command leaving only the ID
-        cmd &= 0xFFFF;
-
-        if (request.inputBuf.size() < 2 || request.outputBuf.empty())
-            throw exception("Inadequate amount of buffers for IOCTL2: I - {}, O - {}", request.inputBuf.size(), request.outputBuf.size());
-        else if (request.inputBuf[0].data() != request.outputBuf[0].data())
-            throw exception("IOCTL2 Input Buffer (0x{:X}) != Output Buffer (0x{:X}) [Input Buffer #2: 0x{:X}]", request.inputBuf[0].data(), request.outputBuf[0].data(), request.inputBuf[1].data());
-
-        span<u8> buffer{};
-        if (request.inputBuf[0].size() >= request.outputBuf[0].size())
-            buffer = request.inputBuf[0];
-        else
-            buffer = request.outputBuf[0];
-
-        response.Push(device->HandleIoctl(cmd, device::IoctlType::Ioctl2, buffer, request.inputBuf[1]));
-        return {};
-    }
-
-    Result INvDrvServices::Ioctl3(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
-        auto fd{request.Pop<u32>()};
-        auto cmd{request.Pop<u32>()};
-
-        auto device{driver->GetDevice(fd)};
-
-        // Strip the permissions from the command leaving only the ID
-        cmd &= 0xFFFF;
-
-        if (request.inputBuf.empty() || request.outputBuf.empty()) {
-            throw exception("Inadequate amount of buffers for IOCTL3: I - {}, O - {}", request.inputBuf.size(), request.outputBuf.size());
-        } else if (request.inputBuf[0].data() != request.outputBuf[0].data()) {
-            if (request.outputBuf.size() >= 2)
-                throw exception("IOCTL3 Input Buffer (0x{:X}) != Output Buffer (0x{:X}) [Output Buffer #2: 0x{:X}]", request.inputBuf[0].data(), request.outputBuf[0].data(), request.outputBuf[1].data());
-            else
-                throw exception("IOCTL3 Input Buffer (0x{:X}) != Output Buffer (0x{:X})", request.inputBuf[0].data(), request.outputBuf[0].data());
-        }
-
-        span<u8> buffer{};
-        if (request.inputBuf[0].size() >= request.outputBuf[0].size())
-            buffer = request.inputBuf[0];
-        else
-            buffer = request.outputBuf[0];
-
-        response.Push(device->HandleIoctl(cmd, device::IoctlType::Ioctl3, buffer, request.outputBuf.size() >= 2 ? request.outputBuf[1] : span<u8>()));
-        return {};
-    }
 
     Result INvDrvServices::SetGraphicsFirmwareMemoryMarginEnabled(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
         return {};

app/src/main/cpp/skyline/services/nvdrv/INvDrvServices.h

@@ -1,9 +1,10 @@
-// SPDX-License-Identifier: MPL-2.0
+// SPDX-License-Identifier: MIT OR MPL-2.0
 // Copyright © 2020 Skyline Team and Contributors (https://github.com/skyline-emu/)
 
 #pragma once
 
 #include <services/serviceman.h>
+#include "types.h"
 
 namespace skyline::service::nvdrv {
     class Driver;
@@ -14,10 +15,13 @@ namespace skyline::service::nvdrv {
      */
     class INvDrvServices : public BaseService {
       private:
-        std::shared_ptr<Driver> driver;
+        Driver &driver; //!< The global nvdrv driver this session accesses
+        SessionContext ctx; //!< Session specific context
+
+        FileDescriptor nextFdIndex{1}; //!< The index for the next allocated file descriptor
 
       public:
-        INvDrvServices(const DeviceState &state, ServiceManager &manager);
+        INvDrvServices(const DeviceState &state, ServiceManager &manager, Driver &driver, const SessionPermissions &perms);
 
         /**
          * @brief Open a specific device and return a FD
@@ -59,13 +63,13 @@ namespace skyline::service::nvdrv {
          * @brief Perform an IOCTL on the specified FD with an extra input buffer
          * @url https://switchbrew.org/wiki/NV_services#Ioctl2
          */
-        Result Ioctl2(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response);
+     //   Result Ioctl2(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response);
 
         /**
          * @brief Perform an IOCTL on the specified FD with an extra output buffer
          * @url https://switchbrew.org/wiki/NV_services#Ioctl3
          */
-        Result Ioctl3(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response);
+     //   Result Ioctl3(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response);
 
         /**
          * @brief Enables the graphics firmware memory margin
@@ -80,8 +84,7 @@ namespace skyline::service::nvdrv {
             SFUNC(0x3, INvDrvServices, Initialize),
             SFUNC(0x4, INvDrvServices, QueryEvent),
             SFUNC(0x8, INvDrvServices, SetAruid),
-            SFUNC(0xB, INvDrvServices, Ioctl2),
-            SFUNC(0xC, INvDrvServices, Ioctl3),
+
             SFUNC(0xD, INvDrvServices, SetGraphicsFirmwareMemoryMarginEnabled)
         )
     };

app/src/main/cpp/skyline/services/nvdrv/core/core.h

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: MIT OR MPL-2.0
+// Copyright © 2021 Skyline Team and Contributors (https://github.com/skyline-emu/)
+
+#pragma once
+
+#include "nvmap.h"
+#include "syncpoint_manager.h"
+
+namespace skyline::service::nvdrv {
+    /**
+     * @brief Holds the global state of nvdrv
+     */
+    struct Core {
+        core::NvMap nvMap;
+        core::SyncpointManager syncpointManager;
+
+        Core(const DeviceState &state) : nvMap(state), syncpointManager(state) {}
+    };
+}

app/src/main/cpp/skyline/services/nvdrv/devices/nvdevice.cpp

@@ -1,11 +1,12 @@
-// SPDX-License-Identifier: MPL-2.0
-// Copyright © 2020 Skyline Team and Contributors (https://github.com/skyline-emu/)
+// SPDX-License-Identifier: MIT OR MPL-2.0
+// Copyright © 2021 Skyline Team and Contributors (https://github.com/skyline-emu/)
 
 #include <cxxabi.h>
-#include <common/trace.h>
 #include "nvdevice.h"
 
 namespace skyline::service::nvdrv::device {
+    NvDevice::NvDevice(const DeviceState &state, Core &core, const SessionContext &ctx) : state(state), core(core), ctx(ctx) {}
+
     const std::string &NvDevice::GetName() {
         if (name.empty()) {
             auto mangledName{typeid(*this).name()};
@@ -18,32 +19,4 @@ namespace skyline::service::nvdrv::device {
         }
         return name;
     }
-
-    NvStatus NvDevice::HandleIoctl(u32 cmd, IoctlType type, span<u8> buffer, span<u8> inlineBuffer) {
-        std::string_view typeString{[type] {
-            switch (type) {
-                case IoctlType::Ioctl:
-                    return "IOCTL";
-                case IoctlType::Ioctl2:
-                    return "IOCTL2";
-                case IoctlType::Ioctl3:
-                    return "IOCTL3";
-            }
-        }()};
-
-        NvDeviceFunctionDescriptor function;
-        try {
-            function = GetIoctlFunction(cmd);
-            state.logger->DebugNoPrefix("{}: {}", typeString, function.name);
-        } catch (std::out_of_range &) {
-            state.logger->Warn("Cannot find IOCTL for device '{}': 0x{:X}", GetName(), cmd);
-            return NvStatus::NotImplemented;
-        }
-        TRACE_EVENT("service", perfetto::StaticString{function.name});
-        try {
-            return function(type, buffer, inlineBuffer);
-        } catch (const std::exception &e) {
-            throw exception("{} ({}: {})", e.what(), typeString, function.name);
-        }
-    }
 }

app/src/main/cpp/skyline/services/nvdrv/devices/nvdevice.h

@@ -1,66 +1,19 @@
-// SPDX-License-Identifier: MPL-2.0
-// Copyright © 2020 Skyline Team and Contributors (https://github.com/skyline-emu/)
+// SPDX-License-Identifier: MIT OR MPL-2.0
+// Copyright © 2021 Skyline Team and Contributors (https://github.com/skyline-emu/)
 
 #pragma once
 
 #include <kernel/ipc.h>
 #include <kernel/types/KEvent.h>
+#include <services/common/result.h>
+#include <services/nvdrv/types.h>
+#include <services/nvdrv/core/core.h>
 
-#define NV_STRINGIFY(string) #string
-#define NVFUNC(id, Class, Function) std::pair<u32, std::pair<NvStatus(Class::*)(IoctlType, span<u8>, span<u8>), const char*>>{id, {&Class::Function, NV_STRINGIFY(Class::Function)}}
-#define NVDEVICE_DECL_AUTO(name, value) decltype(value) name = value
-#define NVDEVICE_DECL(...)                                                                \
-NVDEVICE_DECL_AUTO(functions, frz::make_unordered_map({__VA_ARGS__}));                    \
-NvDeviceFunctionDescriptor GetIoctlFunction(u32 id) override {                            \
-    auto& function{functions.at(id)};                                                     \
-    return NvDeviceFunctionDescriptor{                                                    \
-        reinterpret_cast<DerivedDevice*>(this),                                           \
-        reinterpret_cast<decltype(NvDeviceFunctionDescriptor::function)>(function.first), \
-        function.second                                                                   \
-    };                                                                                    \
-}
+#include "deserialisation/types.h"
 
 namespace skyline::service::nvdrv::device {
     using namespace kernel;
-
-    /**
-     * @brief All the possible error codes returned by the Nvidia driver
-     * @url https://switchbrew.org/wiki/NV_services#Errors
-     */
-    enum class NvStatus : u32 {
-        Success = 0x0, //!< The operation has succeeded
-        NotImplemented = 0x1, //!< The operation is not implemented
-        NotSupported = 0x2, //!< The operation is not supported
-        NotInitialized = 0x3, //!< The operation uses an uninitialized object
-        BadParameter = 0x4, //!< The operation was provided a bad parameter
-        Timeout = 0x5, //!< The operation has timed out
-        InsufficientMemory = 0x6, //!< The device ran out of memory during the operation
-        ReadOnlyAttribute = 0x7, //!< The mutating operation was performed on a read only section
-        InvalidState = 0x8, //!< The state of the device was invalid
-        InvalidAddress = 0x9, //!< The provided address is invalid
-        InvalidSize = 0xA, //!< The provided size is invalid
-        BadValue = 0xB, //!< The operation was provided a bad value
-        AlreadyAllocated = 0xD, //!< An object was tried to be reallocated
-        Busy = 0xE, //!< The device is busy
-        ResourceError = 0xF, //!< There was an error accessing the resource
-        CountMismatch = 0x10, //!< ?
-        SharedMemoryTooSmall = 0x1000, //!< The shared memory segment is too small
-        FileOperationFailed = 0x30003, //!< The file operation has failed
-        DirOperationFailed = 0x30004, //!< The directory operation has failed
-        IoctlFailed = 0x3000F, //!< The IOCTL operation has failed
-        AccessDenied = 0x30010, //!< The access to a resource was denied
-        FileNotFound = 0x30013, //!< A file was not found
-        ModuleNotPresent = 0xA000E, //!< A module was not present
-    };
-
-    /**
-     * @brief The IOCTL call variants, they have different buffer configurations
-     */
-    enum class IoctlType : u8 {
-        Ioctl,  //!< 1 input/output buffer
-        Ioctl2, //!< 1 input/output buffer + 1 input buffer
-        Ioctl3, //!< 1 input/output buffer + 1 output buffer
-    };
+    using namespace deserialisation;
 
     /**
      * @brief NvDevice is the base class that all /dev/nv* devices inherit from
@@ -71,40 +24,25 @@ namespace skyline::service::nvdrv::device {
 
       protected:
         const DeviceState &state;
-
-        class DerivedDevice; //!< A placeholder derived class which is used for class function semantics
-
-        /**
-         * @brief A per-function descriptor for NvDevice functions
-         */
-        struct NvDeviceFunctionDescriptor {
-            DerivedDevice *clazz; //!< A pointer to the class that this was derived from, it's used as the 'this' pointer for the function
-            NvStatus (DerivedDevice::*function)(IoctlType, span<u8>, span<u8>); //!< A function pointer to the implementation of the function
-            const char *name; //!< A pointer to a static string in the format "Class::Function" for the specific device class/function
-
-            constexpr NvStatus operator()(IoctlType type, span<u8> buffer, span<u8> inlineBuffer) {
-                return (clazz->*function)(type, buffer, inlineBuffer);
-            }
-        };
+        Core &core;
+        SessionContext ctx;
 
       public:
-        NvDevice(const DeviceState &state) : state(state) {}
+        NvDevice(const DeviceState &state, Core &core, const SessionContext &ctx);
 
         virtual ~NvDevice() = default;
 
-        virtual NvDeviceFunctionDescriptor GetIoctlFunction(u32 id) = 0;
-
         /**
          * @return The name of the class
          * @note The lifetime of the returned string is tied to that of the class
          */
         const std::string &GetName();
 
-        /**
-         * @brief Handles IOCTL calls for devices
-         * @param cmd The IOCTL command that was called
-         */
-        NvStatus HandleIoctl(u32 cmd, IoctlType type, span<u8> buffer, span<u8> inlineBuffer);
+        virtual PosixResult Ioctl(IoctlDescriptor cmd, span<u8> buffer) = 0;
+
+        virtual PosixResult Ioctl2(IoctlDescriptor cmd, span<u8> buffer, span<u8> inlineOutput) { return PosixResult::NotSupported; }
+
+        virtual PosixResult Ioctl3(IoctlDescriptor cmd, span<u8> buffer, span<u8> inlineInput) { return PosixResult::NotSupported; }
 
         virtual std::shared_ptr<kernel::type::KEvent> QueryEvent(u32 eventId) {
             return nullptr;

app/src/main/cpp/skyline/services/nvdrv/driver.cpp

@@ -1,61 +1,121 @@
-// SPDX-License-Identifier: MPL-2.0
+// SPDX-License-Identifier: MIT OR MPL-2.0
 // Copyright © 2020 Skyline Team and Contributors (https://github.com/skyline-emu/)
 
 #include "driver.h"
-#include "devices/nvhost_ctrl.h"
-#include "devices/nvhost_ctrl_gpu.h"
 #include "devices/nvmap.h"
-#include "devices/nvhost_channel.h"
-#include "devices/nvhost_as_gpu.h"
+#include "devices/nvhost/ctrl.h"
+#include "devices/nvhost/ctrl_gpu.h"
+#include "devices/nvhost/gpu_channel.h"
+#include "devices/nvhost/as_gpu.h"
+
 
 namespace skyline::service::nvdrv {
-    Driver::Driver(const DeviceState &state) : state(state), hostSyncpoint(state) {}
+    Driver::Driver(const DeviceState &state) : state(state), core(state) {}
 
-    u32 Driver::OpenDevice(std::string_view path) {
-        state.logger->Debug("Opening NVDRV device ({}): {}", fdIndex, path);
+    NvResult Driver::OpenDevice(std::string_view path, FileDescriptor fd, const SessionContext &ctx) {
+        state.logger->Debug("Opening NvDrv device ({}): {}", fd, path);
+        auto pathHash{util::Hash(path)};
 
-        switch (util::Hash(path)) {
-            #define NVDEVICE(type, name, devicePath)                     \
-                case util::Hash(devicePath): {                           \
-                    std::shared_ptr<device::type> device{};              \
-                    if (name.expired()) {                                \
-                        device = std::make_shared<device::type>(state);  \
-                        name = device;                                   \
-                    } else {                                             \
-                        device = name.lock();                            \
-                    }                                                    \
-                    devices.push_back(device);                           \
+        #define DEVICE_SWITCH(cases) \
+            switch (pathHash) {      \
+                cases;               \
+                default:             \
                     break;           \
             }
-            NVDEVICE_LIST
-            #undef NVDEVICE
 
+        #define DEVICE_CASE(path, object) \
+            case util::Hash(path): \
+                devices.emplace(fd, std::make_unique<device::object>(state, core, ctx)); \
+                return NvResult::Success;
+
+        DEVICE_SWITCH(
+            DEVICE_CASE("/dev/nvmap", NvMap)
+            DEVICE_CASE("/dev/nvhost-ctrl", nvhost::Ctrl)
+        );
+
+        if (ctx.perms.AccessGpu) {
+            DEVICE_SWITCH(
+                DEVICE_CASE("/dev/nvhost-as-gpu", nvhost::AsGpu)
+                DEVICE_CASE("/dev/nvhost-ctrl-gpu", nvhost::CtrlGpu)
+                DEVICE_CASE("/dev/nvhost-gpu", nvhost::GpuChannel)
+            );
+        }/*
+
+        if (ctx.perms.AccessVic) {
+            switch (pathHash) {
+                ENTRY("/dev/nvhost-vic", nvhost::Vic)
                 default:
-                throw exception("Cannot find NVDRV device");
+                    break;
+            }
         }
 
-        return fdIndex++;
+        if (ctx.perms.AccessVideoDecoder) {
+            switch (pathHash) {
+                ENTRY("/dev/nvhost-nvdec", nvhost::NvDec)
+                default:
+                    break;
+            }
         }
 
-    std::shared_ptr<device::NvDevice> Driver::GetDevice(u32 fd) {
+        if (ctx.perms.AccessJpeg) {
+            switch (pathHash) {
+                ENTRY("/dev/nvhost-nvjpg", nvhost::NvJpg)
+                default:
+                    break;
+            }
+        }*/
+
+        #undef DEVICE_CASE
+        #undef DEVICE_SWITCH
+
+        // Device doesn't exist/no permissions
+        return NvResult::FileOperationFailed;
+    }
+
+    static NvResult ConvertResult(PosixResult result) {
+        switch (result) {
+            case PosixResult::Success:
+                return NvResult::Success;
+            case PosixResult::NotPermitted:
+                return NvResult::AccessDenied;
+            case PosixResult::TryAgain:
+                return NvResult::Timeout;
+            case PosixResult::Busy:
+                return NvResult::Busy;
+            case PosixResult::InvalidArgument:
+                return NvResult::BadValue;
+            case PosixResult::InappropriateIoctlForDevice:
+                return NvResult::IoctlFailed;
+            case PosixResult::NotSupported:
+                return NvResult::NotSupported;
+            case PosixResult::TimedOut:
+                return NvResult::Timeout;
+            default:
+                throw exception("Unhandled POSIX result: {}!", static_cast<i32>(result));
+        }
+
+    }
+    NvResult Driver::Ioctl(u32 fd, IoctlDescriptor cmd, span<u8> buffer) {
         try {
-            auto item{devices.at(fd)};
-            if (!item)
-                throw exception("GetDevice was called with a closed file descriptor: 0x{:X}", fd);
-            return item;
-        } catch (std::out_of_range) {
+            return ConvertResult(devices.at(fd)->Ioctl(cmd, buffer));
+        } catch (const std::out_of_range &) {
             throw exception("GetDevice was called with invalid file descriptor: 0x{:X}", fd);
         }
     }
 
     void Driver::CloseDevice(u32 fd) {
         try {
-            auto &device{devices.at(fd)};
-            device.reset();
+            devices.at(fd).reset();
         } catch (const std::out_of_range &) {
             state.logger->Warn("Trying to close non-existent FD");
         }
     }
 
-    std::weak_ptr<Driver> driver{};
+    std::shared_ptr<kernel::type::KEvent> Driver::QueryEvent(u32 fd, u32 eventId) {
+        try {
+            return devices.at(fd)->QueryEvent(eventId);
+        } catch (const std::exception &) {
+            throw exception("QueryEvent was called with invalid file descriptor: 0x{:X}", fd);
+        }
+    }
 }

app/src/main/cpp/skyline/services/nvdrv/driver.h

@@ -1,76 +1,45 @@
-// SPDX-License-Identifier: MPL-2.0
+// SPDX-License-Identifier: MIT OR MPL-2.0
 // Copyright © 2020 Skyline Team and Contributors (https://github.com/skyline-emu/)
 
 #pragma once
 
-#include "devices/nvhost_syncpoint.h"
-
-#define NVDEVICE_LIST                                              \
-    NVDEVICE(NvHostCtrl,    nvHostCtrl,    "/dev/nvhost-ctrl")     \
-    NVDEVICE(NvHostChannel, nvHostGpu,     "/dev/nvhost-gpu")      \
-    NVDEVICE(NvHostChannel, nvHostNvdec,   "/dev/nvhost-nvdec")    \
-    NVDEVICE(NvHostChannel, nvHostVic,     "/dev/nvhost-vic")      \
-    NVDEVICE(NvMap,         nvMap,         "/dev/nvmap")           \
-    NVDEVICE(NvHostAsGpu,   nvHostAsGpu,   "/dev/nvhost-as-gpu")   \
-    NVDEVICE(NvHostCtrlGpu, nvHostCtrlGpu, "/dev/nvhost-ctrl-gpu")
+#include <common.h>
+#include "types.h"
+#include "devices/nvdevice.h"
+#include "core/core.h"
 
 namespace skyline::service::nvdrv {
-    namespace device {
-        class NvDevice;
-
-        #define NVDEVICE(type, name, path) class type;
-        NVDEVICE_LIST
-        #undef NVDEVICE
-    }
-
-    /**
-     * @brief nvnflinger:dispdrv or nns::hosbinder::IHOSBinderDriver is responsible for writing buffers to the display
-     */
     class Driver {
       private:
         const DeviceState &state;
-        std::vector<std::shared_ptr<device::NvDevice>> devices; //!< A vector of shared pointers to NvDevice object that correspond to FDs
-        u32 fdIndex{}; //!< The next file descriptor to assign
+        std::unordered_map<FileDescriptor, std::unique_ptr<device::NvDevice>> devices;
 
       public:
-        NvHostSyncpoint hostSyncpoint;
-
-        #define NVDEVICE(type, name, path) std::weak_ptr<device::type> name;
-        NVDEVICE_LIST
-        #undef NVDEVICE
+        Core core; //!< The core global state object of nvdrv that is accessed by devices
 
         Driver(const DeviceState &state);
 
         /**
-         * @brief Open a specific device and return a FD
-         * @param path The path of the device to open an FD to
-         * @return The file descriptor to the device
+         * @brief Creates a new device as specified by path
+         * @param path The /dev path that corresponds to the device
+         * @param fd The fd that will be used to refer to the device
+         * @param ctx The context to be attached to the device
          */
-        u32 OpenDevice(std::string_view path);
+        NvResult OpenDevice(std::string_view path, FileDescriptor fd, const SessionContext &ctx);
 
         /**
-         * @brief Returns a particular device with a specific FD
-         * @param fd The file descriptor to retrieve
-         * @return A shared pointer to the device
+         * @brief Calls an IOCTL on the device specified by `fd`
          */
-        std::shared_ptr<device::NvDevice> GetDevice(u32 fd);
+        NvResult Ioctl(u32 fd, IoctlDescriptor cmd, span<u8> buffer);
 
         /**
-         * @brief Returns a particular device with a specific FD
-         * @tparam objectClass The class of the device to return
-         * @param fd The file descriptor to retrieve
-         * @return A shared pointer to the device
+         * @brief Queries a KEvent for the given `eventId` for the device specified by `fd`
          */
-        template<typename objectClass>
-        std::shared_ptr<objectClass> GetDevice(u32 fd) {
-            return std::static_pointer_cast<objectClass>(GetDevice(fd));
-        }
+        std::shared_ptr<kernel::type::KEvent> QueryEvent(u32 fd, u32 eventId);
 
         /**
-         * @brief Closes the specified device with its file descriptor
+         * @brief Closes the device specified by `fd`
          */
         void CloseDevice(u32 fd);
     };
-
-    extern std::weak_ptr<Driver> driver; //!< A globally shared instance of the Driver
 }

app/src/main/cpp/skyline/services/nvdrv/types.h

@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: MIT OR MPL-2.0
+// Copyright © 2021 Skyline Team and Contributors (https://github.com/skyline-emu/)
+
+#pragma once
+
+#include <common.h>
+
+namespace skyline::service::nvdrv {
+    using FileDescriptor = i32;
+    constexpr FileDescriptor InvalidFileDescriptor{-1};
+
+    /**
+     * @brief Holds the permissions for an nvdrv instance
+     */
+    struct SessionPermissions {
+        bool AccessGpu;
+        bool AccessGpuDebug;
+        bool AccessGpuSchedule;
+        bool AccessVic;
+        bool AccessVideoEncoder;
+        bool AccessVideoDecoder;
+        bool AccessTsec;
+        bool AccessJpeg;
+        bool AccessDisplay;
+        bool AccessImportMemory;
+        bool NoCheckedAruid;
+        bool ModifyGraphicsMargin;
+        bool DuplicateNvMapHandles;
+        bool ExportNvMapHandles;
+    };
+
+    /**
+     * @brief Holds the per-session context for nvdrv
+     */
+    struct SessionContext {
+        SessionPermissions perms;
+        bool internalSession;
+    };
+
+    /**
+     * @brief Permissions that applications have when using the 'nvdrv' service
+     */
+    static constexpr SessionPermissions ApplicationSessionPermissions {
+        .AccessGpu = true,
+        .AccessGpuDebug = true,
+        .AccessVic = true,
+        .AccessVideoDecoder = true,
+        .ModifyGraphicsMargin = true
+    };
+
+    /**
+     * @brief An bitfield struct that unpacks an ioctl number, used as an alternative to Linux's macros
+     */
+    union IoctlDescriptor {
+        struct {
+            u8 function; //!< The function number corresponding to a specific call in the driver
+            i8 magic; //!< Unique to each driver
+            u16 size : 14; //!< Size of the argument buffer
+            bool in : 1; //!< Guest is writing, we are reading
+            bool out : 1; //!< Guest is reading, we are writing
+        };
+
+        u32 raw;
+    };
+    static_assert(sizeof(IoctlDescriptor) == sizeof(u32));
+
+    /**
+     * @brief NvRm result codes that are translated from the POSIX error codes used internally
+     * @url https://switchbrew.org/wiki/NV_services#NvError
+     */
+    enum class NvResult : i32 {
+        Success = 0x0,
+        NotImplemented = 0x1,
+        NotSupported = 0x2,
+        NotInitialized = 0x3,
+        BadParameter = 0x4,
+        Timeout = 0x5,
+        InsufficientMemory = 0x6,
+        ReadOnlyAttribute = 0x7,
+        InvalidState = 0x8,
+        InvalidAddress = 0x9,
+        InvalidSize = 0xA,
+        BadValue = 0xB,
+        AlreadyAllocated = 0xD,
+        Busy = 0xE,
+        ResourceError = 0xF,
+        CountMismatch = 0x10,
+        Overflow = 0x11,
+        FileOperationFailed = 0x30003,
+        AccessDenied = 0x30010,
+        IoctlFailed = 0x3000F
+    };
+}

app/src/main/cpp/skyline/services/serviceman.cpp

@@ -18,7 +18,8 @@
 #include "glue/IStaticService.h"
 #include "services/timesrv/core.h"
 #include "fssrv/IFileSystemProxy.h"
-#include "services/nvdrv/INvDrvServices.h"
+#include "nvdrv/INvDrvServices.h"
+#include "nvdrv/driver.h"
 #include "hosbinder/IHOSBinderDriver.h"
 #include "visrv/IApplicationRootService.h"
 #include "visrv/ISystemRootService.h"
@@ -48,8 +49,9 @@
 namespace skyline::service {
     struct GlobalServiceState {
         timesrv::core::TimeServiceObject timesrv;
+        nvdrv::Driver nvdrv;
 
-        explicit GlobalServiceState(const DeviceState &state) : timesrv(state) {}
+        explicit GlobalServiceState(const DeviceState &state) : timesrv(state), nvdrv(state) {}
     };
 
     ServiceManager::ServiceManager(const DeviceState &state) : state(state), smUserInterface(std::make_shared<sm::IUserInterface>(state, *this)), globalServiceState(std::make_shared<GlobalServiceState>(state)) {}
@@ -76,11 +78,8 @@ namespace skyline::service {
             SERVICE_CASE(glue::IStaticService, "time:r", globalServiceState->timesrv.managerServer.GetStaticServiceAsRepair(state, *this), globalServiceState->timesrv, timesrv::constant::StaticServiceRepairPermissions)
             SERVICE_CASE(glue::IStaticService, "time:u", globalServiceState->timesrv.managerServer.GetStaticServiceAsUser(state, *this), globalServiceState->timesrv, timesrv::constant::StaticServiceUserPermissions)
             SERVICE_CASE(fssrv::IFileSystemProxy, "fsp-srv")
-            SERVICE_CASE(nvdrv::INvDrvServices, "nvdrv")
-            SERVICE_CASE(nvdrv::INvDrvServices, "nvdrv:a")
-            SERVICE_CASE(nvdrv::INvDrvServices, "nvdrv:s")
-            SERVICE_CASE(nvdrv::INvDrvServices, "nvdrv:t")
-            SERVICE_CASE(hosbinder::IHOSBinderDriver, "dispdrv")
+            SERVICE_CASE(nvdrv::INvDrvServices, "nvdrv", globalServiceState->nvdrv, nvdrv::ApplicationSessionPermissions)
+            SERVICE_CASE(hosbinder::IHOSBinderDriver, "dispdrv", globalServiceState->nvdrv.core.nvMap)
             SERVICE_CASE(visrv::IApplicationRootService, "vi:u")
             SERVICE_CASE(visrv::ISystemRootService, "vi:s")
             SERVICE_CASE(visrv::IManagerRootService, "vi:m")