Atmosphere/libraries/libmesosphere/include/mesosphere/kern_k_transfer_memory.hpp

/*
 * Copyright (c) Atmosphère-NX
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#pragma once
#include <mesosphere/kern_common.hpp>
#include <mesosphere/kern_k_auto_object.hpp>
#include <mesosphere/kern_slab_helpers.hpp>

namespace ams::kern {

    class KTransferMemory final : public KAutoObjectWithSlabHeapAndContainer<KTransferMemory, KAutoObjectWithList> {
        MESOSPHERE_AUTOOBJECT_TRAITS(KTransferMemory, KAutoObject);
        private:
            util::TypedStorage<KPageGroup> m_page_group;
            KProcess *m_owner;
            KProcessAddress m_address;
            KLightLock m_lock;
            ams::svc::MemoryPermission m_owner_perm;
            bool m_is_initialized;
            bool m_is_mapped;
        public:
            explicit KTransferMemory() : m_owner(nullptr), m_address(Null<KProcessAddress>), m_owner_perm(ams::svc::MemoryPermission_None), m_is_initialized(false), m_is_mapped(false) {
                /* ... */
            }

            Result Initialize(KProcessAddress addr, size_t size, ams::svc::MemoryPermission own_perm);
            void Finalize();

            bool IsInitialized() const { return m_is_initialized; }
            uintptr_t GetPostDestroyArgument() const { return reinterpret_cast<uintptr_t>(m_owner); }
            static void PostDestroy(uintptr_t arg);

            Result Map(KProcessAddress address, size_t size, ams::svc::MemoryPermission map_perm);
            Result Unmap(KProcessAddress address, size_t size);

            KProcess *GetOwner() const { return m_owner; }
            KProcessAddress GetSourceAddress() { return m_address; }
            size_t GetSize() const { return m_is_initialized ? GetReference(m_page_group).GetNumPages() * PageSize : 0; }

            constexpr uintptr_t GetHint() const {
                /* Get memory size. */
                const size_t size = this->GetSize();

                /* TODO: Is this architecture specific? */
                if (size >= 2_MB) {
                    return GetInteger(m_address) & (2_MB - 1);
                } else if (size >= 64_KB) {
                    return GetInteger(m_address) & (64_KB - 1);
                } else if (size >= 4_KB) {
                    return GetInteger(m_address) & (4_KB - 1);
                } else {
                    return 0;
                }
            }
    };

}