fs: implement newer allocator templates

libraries/libstratosphere/include/stratosphere/fs/fs_memory_management.hpp

@@ -28,6 +28,94 @@ namespace ams::fs {
         void *Allocate(size_t size);
         void Deallocate(void *ptr, size_t size);
 
+        void LockAllocatorMutex();
+        void UnlockAllocatorMutex();
+
+        void *AllocateUnsafe(size_t size);
+        void DeallocateUnsafe(void *ptr, size_t size);
+
+        class AllocatorImpl {
+            public:
+                static ALWAYS_INLINE void *Allocate(size_t size) { return ::ams::fs::impl::Allocate(size); }
+                static ALWAYS_INLINE void *AllocateUnsafe(size_t size) { return ::ams::fs::impl::AllocateUnsafe(size); }
+
+                static ALWAYS_INLINE void Deallocate(void *ptr, size_t size) { return ::ams::fs::impl::Deallocate(ptr, size); }
+                static ALWAYS_INLINE void DeallocateUnsafe(void *ptr, size_t size) { return ::ams::fs::impl::DeallocateUnsafe(ptr, size); }
+
+                static ALWAYS_INLINE void LockAllocatorMutex() { return ::ams::fs::impl::LockAllocatorMutex(); }
+                static ALWAYS_INLINE void UnlockAllocatorMutex() { return ::ams::fs::impl::UnlockAllocatorMutex(); }
+        };
+
+        template<typename T, typename Impl, bool AllocateWhileLocked>
+        class AllocatorTemplate : public std::allocator<T> {
+            public:
+                template<typename U>
+                struct rebind {
+                    using other = AllocatorTemplate<U, Impl, AllocateWhileLocked>;
+                };
+            private:
+                bool m_allocation_failed;
+            private:
+                static ALWAYS_INLINE T *AllocateImpl(::std::size_t n) {
+                    if constexpr (AllocateWhileLocked) {
+                        auto * const p = Impl::AllocateUnsafe(sizeof(T) * n);
+                        Impl::UnlockAllocatorMutex();
+                        return static_cast<T *>(p);
+                    } else {
+                        return static_cast<T *>(Impl::Allocate(sizeof(T) * n));
+                    }
+                }
+            public:
+                AllocatorTemplate() : m_allocation_failed(false) { /* ... */ }
+
+                template<typename U>
+                AllocatorTemplate(const AllocatorTemplate<U, Impl, AllocateWhileLocked> &rhs) : m_allocation_failed(rhs.IsAllocationFailed()) { /* ... */ }
+
+                bool IsAllocationFailed() const { return m_allocation_failed; }
+
+                [[nodiscard]] T *allocate(::std::size_t n) {
+                    auto * const p = AllocateImpl(n);
+                    if (AMS_UNLIKELY(p == nullptr) && n) {
+                        m_allocation_failed = true;
+                    }
+                    return p;
+                }
+
+                void deallocate(T *p, ::std::size_t n) {
+                    Impl::Deallocate(p, sizeof(T) * n);
+                }
+        };
+
+        template<typename T, typename Impl>
+        using AllocatorTemplateForAllocateShared = AllocatorTemplate<T, Impl, true>;
+
+        template<typename T, template<typename, typename> class AllocatorTemplateT, typename Impl, typename... Args>
+        std::shared_ptr<T> AllocateSharedImpl(Args &&... args) {
+            /* Try to allocate. */
+            {
+                /* Acquire exclusive access to the allocator. */
+                Impl::LockAllocatorMutex();
+
+                /* Check that we can allocate memory (using overestimate of 0x80 + sizeof(T)). */
+                if (auto * const p = Impl::Allocate(0x80 + sizeof(T)); AMS_LIKELY(p != nullptr)) {
+                    /* Free the memory we allocated. */
+                    Impl::Deallocate(p, 0x80 + sizeof(T));
+
+                    /* Get allocator type. */
+                    using AllocatorType = AllocatorTemplateT<T, Impl>;
+
+                    /* Allocate the shared pointer. */
+                    return std::allocate_shared<T>(AllocatorType{}, std::forward<Args>(args)...);
+                } else {
+                    /* We can't allocate. */
+                    Impl::UnlockAllocatorMutex();
+                }
+            }
+
+            /* We failed. */
+            return nullptr;
+        }
+
         class Deleter {
             private:
                 size_t m_size;
@@ -59,4 +147,9 @@ namespace ams::fs {
 
     }
 
+    template<typename T, typename... Args>
+    std::shared_ptr<T> AllocateShared(Args &&... args) {
+        return ::ams::fs::impl::AllocateSharedImpl<T, ::ams::fs::impl::AllocatorTemplateForAllocateShared, ::ams::fs::impl::AllocatorImpl>(std::forward<Args>(args)...);
+    }
+
 }

libraries/libstratosphere/source/fs/fs_memory_management.cpp

@@ -19,7 +19,7 @@ namespace ams::fs {
 
     namespace {
 
-        bool g_used_default_allocator;
+        constinit bool g_used_default_allocator = false;
 
         void *DefaultAllocate(size_t size) {
             g_used_default_allocator = true;
@@ -31,7 +31,7 @@ namespace ams::fs {
             ams::Free(ptr);
         }
 
-        constinit os::SdkMutex g_lock;
+        constinit os::SdkMutex g_mutex;
         constinit AllocateFunction g_allocate_func     = DefaultAllocate;
         constinit DeallocateFunction g_deallocate_func = DefaultDeallocate;
 
@@ -59,26 +59,61 @@ namespace ams::fs {
 
     namespace impl {
 
-        void *Allocate(size_t size) {
-            void *ptr;
-            {
-                std::scoped_lock lk(g_lock);
-                ptr = g_allocate_func(size);
-                if (!util::IsAligned(reinterpret_cast<uintptr_t>(ptr), RequiredAlignment)) {
-                    R_ABORT_UNLESS(fs::ResultAllocatorAlignmentViolation());
-                }
+        void LockAllocatorMutex() {
+            g_mutex.Lock();
+        }
+
+        void UnlockAllocatorMutex() {
+            g_mutex.Unlock();
+        }
+
+        void *AllocateUnsafe(size_t size) {
+            /* Check pre-conditions. */
+            AMS_ASSERT(g_mutex.IsLockedByCurrentThread());
+
+            /* Allocate. */
+            void * const ptr = g_allocate_func(size);
+
+            /* Check alignment. */
+            if (AMS_UNLIKELY(!util::IsAligned(reinterpret_cast<uintptr_t>(ptr), RequiredAlignment))) {
+                R_ABORT_UNLESS(fs::ResultAllocatorAlignmentViolation());
             }
+
+            /* Return allocated pointer. */
             return ptr;
         }
 
-        void Deallocate(void *ptr, size_t size) {
-            if (ptr == nullptr) {
-                return;
-            }
-            std::scoped_lock lk(g_lock);
+        void DeallocateUnsafe(void *ptr, size_t size) {
+            /* Check pre-conditions. */
+            AMS_ASSERT(g_mutex.IsLockedByCurrentThread());
+
+            /* Deallocate the pointer. */
             g_deallocate_func(ptr, size);
         }
 
+        void *Allocate(size_t size) {
+            /* Check pre-conditions. */
+            AMS_ASSERT(g_allocate_func != nullptr);
+
+            /* Lock the allocator. */
+            std::scoped_lock lk(g_mutex);
+
+            return AllocateUnsafe(size);
+        }
+
+        void Deallocate(void *ptr, size_t size) {
+            /* Check pre-conditions. */
+            AMS_ASSERT(g_deallocate_func != nullptr);
+
+            /* If the pointer is non-null, deallocate it. */
+            if (ptr != nullptr) {
+                /* Lock the allocator. */
+                std::scoped_lock lk(g_mutex);
+
+                DeallocateUnsafe(ptr, size);
+            }
+        }
+
     }
 
 }

libraries/libstratosphere/source/fssystem/fssystem_nca_file_system_driver.cpp

@@ -352,7 +352,7 @@ namespace ams::fssystem {
         R_UNLESS(storage_size > 0, fs::ResultInvalidNcaHeader());
 
         /* Allocate a substorage. */
-        *out = AllocateShared<DerivedStorageHolder<fs::SubStorage, 0>>(m_reader->GetBodyStorage(), storage_offset, storage_size, m_reader);
+        *out = fssystem::AllocateShared<DerivedStorageHolder<fs::SubStorage, 0>>(m_reader->GetBodyStorage(), storage_offset, storage_size, m_reader);
         R_UNLESS(*out != nullptr, fs::ResultAllocationFailureInAllocateShared());
 
         return ResultSuccess();