In certain situations such as constant buffer updates, we desire to use the guest buffer as a shadow buffer forwarding all writes directly to it while we update the host using inline buffer updates so they happen in-sequence. This requires special behavior as we cannot let any synchronization operations take place as they would break the shadow buffer, as a result, an external synchronization flag has been added to prevent this from happening.
It should be noted that this flag is not respected for buffer recreation which will lead to UB, this can and will break updates in certain cases and this change isn't complete without buffer manager support.
The offset of the view wasn't added to the `vkCmdUpdateBuffer`, this would cause the offset to be incorrect given the buffer was a view of a larger buffer that wasn't the start of it. This commit fixes that by adding the offset of the view to the buffer update.
We didn't call `MarkGpuDirty` on textures/buffers prior to GPU usage, this would cause them to not be R/W protected when they should be and provide outdated copies if there were any read accesses from the CPU (which are not possible at the moment since we assume all accesses are writes at the moment). This has now been fixed by calling it after synchronizing the resource.
The terminology "Non-Graphics pass" was deemed to be fairly inaccurate since it simply covered all Vulkan commands (not "passes") outside the render-pass scope, these may be graphical operations such as blits and therefore it is more accurate to use the new terminology of "Outside-RenderPass command" due to the lack of such an implication while being consistent with the Vulkan specification.
Previously constant buffer updates would be handled on the CPU and only the end result would be synced to the GPU before execute. This caused issues as if the constant buffer contents was changed between each draw in a renderpass (e.g. text rendering) the draws themselves would only see the final resulting constant buffer. Fix this by updating cbufs on the GPU/CPU seperately, only ever syncing them back at the start or after a guest side CPU write, at the moment only a single word is updated at a time however this can be optimised in the future to batch all consecutive updates into one large one.
We require certain buffers to only be on the host while being accessible through the same abstractions as a guest buffer as they must be interchangeable in usage.
We needed to block stack frame lookups past JNI code as Java doesn't follow the ARMv8 frame pointer ABI which leads to invalid pointer dereferences. Any JNI function that throws or handles exceptions must do this now or it may lead to a `SIGSEGV`.
Some games may pass empty TICs as inputs to shaders while not actually using them within the shader. Create an empty texture and pass this in instead when we hit this case, the nullDescriptor feature could be used but it's not supported by all devices so we chose to do it this way instead.
Skyline's `exception` class now stores a list of all stack frames during the invocation of the exception. These can later be parsed by the exception handler to generate a human-readable stack trace. To assist with more complete stack traces, `-fno-omit-frame-pointer` is now passed on debug builds which forces the inclusion of frames on function calls.
NCE is implicitly depended on by the `GPU` class due to the NCE Memory Trapping API so the destruction of it must take place after the destruction of the `GPU` class. Additionally, to prevent bugs the NCE destructor must set `staticNce` to `nullptr` as the signal handler will potentially access a destroyed instance of NCE otherwise.
Without this sRGB textures would be interpreted as RGB leading to colours being slighly off. The sRGB flag isn't stored as part of format word so we reuse the _pad_ field of it to store the flag for the switch case.
We don't want to actually exit the process as it'll automatically be restarted gracefully due to a timeout after being unable to exit within a fixed duration so we just want to infinite sleep during termination. This should fix issues where exiting any game would cause the app to force close after some time as exception signal handling would fail in the background, the app should stay open now and automatically restart itself when another game is loaded in.
A lot of logs are incomplete due to being unable to flush inside the signal handler, now we flush after any exceptions so that there is a guarantee of any exceptions being logged as this is crucial for proper debugging.
B5G6R5 isn't generally supported by the swapchain and the format is used for R5G6B5 with swapped R/B channels to avoid aliasing so we reverse that by using R5G6B5 as the underlying Vulkan format for the swapchain which should be automatically handled by the driver for any copies from B5G6R5 textures and the data representation should be the same as B5G6R5 with swapped R/B channels so not reporting the correct texture::Format should be fine.
The DMA engine is used to perform DMA buffer/texture copies directly on the GPU. It can deswizzle arbritary regions of input textures, perform component remapping and swizzle into output textures.
This impl only supports 1D buffer copies, 2D ones will come later.
If we have a Nx1x1 image then determining the type from dimensions will result in a 1D image being created thus preventing us from creating a 2D view. By using the image view type we can avoid this for textures from TICs since we know in advance how they will be used
This enforces that the depth RT outlives the draw, without this the depth RT could be freed while in active use by command executor leading to UAFs and crashes.
This was erroneously included while migrating from older code where stack creation was entirely handled with host constructs such as `mmap` directly to using `KPrivateMemory` to manage it, we would create a guard page with `mprotect` that the guest was unaware about and would cause a segfault when a guest accessed the extents of the stack as reported to the guest.
A partial implementation of the `GetThreadContext3` SVC, we cannot return the whole thread context as the kernel only stores the registers we need according to the ARMv8 ABI convention and so far usages of this SVC do not require the unavailable registers but all future usage must be monitored and potentially require extending the amount of saved registers.
The vibration device had to be set manually prior which led to it generally not being set at all even though a user might want vibration, this commit fixes that by making controller #0 use the built-in vibrator by default.
Any Skyline files that should have been user-accessible were moved from `/data/data/skyline.emu/files` to `/sdcard/Android/data/skyline.emu/files` as the former directory is entirely private and cannot be accessed without either adb or root. This made retrieving certain data such as saves or loading custom driver shared objects extremely hard to do while this can be trivially done now.
In some games such as SMO thousands of constant buffers are bound per frame which was causing an unreasonable number of lookups in both vmm and the buffer manager. Work around this by introducing a simple hashmap based cache, eviction is currently unsupported but not really necessary yet due to the small size of the buffers in the cache.
We cannot ignore accesses from the host to a region protected by the NCE Memory Trapping API, there's often access to regions which have overlap with a protected region unintentionally and those accesses need to be handled correctly rather than leading to a crash. This is done by implementing an additional signal handler `NCE::HostSignalHandler` to lookup any potential traps on a `SIGSEGV` and handle them correctly or when there isn't a corresponding trap raise a `SIGTRAP` when debugger is connected or delegate to `signal::ExceptionalSignalHandler` when it isn't.
To cut down memory usage we now page out memory that is RW trapped via the NCE memory trapping API, the callbacks are supposed to page in the memory. This behavior is backed up by Texture/Buffer syncing which would read the host copies of data and write it to the guest, by paging the corresponding data on the guest we're avoiding redundant memory usage.
The `FileDescriptor` class is a RAII wrapper over FDs which handles their lifetimes alongside other C++ semantics such as moving and copying. It has been used in `skyline::kernel::MemoryManager` to handle the lifetime of the ashmem FD correctly, it wasn't being destroyed earlier which can result in leaking FDs across runs.
Initially this commit was only intended to update LLVM but due to a compilation error on latest LLVM libcxx due to the C++ stdlib header `<algorithm>` being a transitive dependency that is no longer transitively included on the latest LLVM libcxx (as of https://reviews.llvm.org/D119667), this required changes in Skyline and Oboe which were done in https://github.com/google/oboe/pull/1521 and the submodule has been updated to include those changes.
