1 files changed, 245 insertions, 0 deletions
diff --git a/src/core/hle/kernel/vm_manager.cpp b/src/core/hle/kernel/vm_manager.cpp
new file mode 100644
index 00000000..b2dd2154
--- /dev/null
+++ b/src/core/hle/kernel/vm_manager.cpp
@@ -0,0 +1,245 @@
+// Copyright 2015 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/assert.h"
+
+#include "core/hle/kernel/vm_manager.h"
+#include "core/memory_setup.h"
+
+namespace Kernel {
+
+bool VirtualMemoryArea::CanBeMergedWith(const VirtualMemoryArea& next) const {
+    ASSERT(base + size == next.base);
+    if (permissions != next.permissions ||
+            meminfo_state != next.meminfo_state ||
+            type != next.type) {
+        return false;
+    }
+    if (type == VMAType::AllocatedMemoryBlock &&
+            (backing_block != next.backing_block || offset + size != next.offset)) {
+        return false;
+    }
+    if (type == VMAType::BackingMemory && backing_memory + size != next.backing_memory) {
+        return false;
+    }
+    if (type == VMAType::MMIO && paddr + size != next.paddr) {
+        return false;
+    }
+    return true;
+}
+
+VMManager::VMManager() {
+    Reset();
+}
+
+void VMManager::Reset() {
+    vma_map.clear();
+
+    // Initialize the map with a single free region covering the entire managed space.
+    VirtualMemoryArea initial_vma;
+    initial_vma.size = MAX_ADDRESS;
+    vma_map.emplace(initial_vma.base, initial_vma);
+
+    UpdatePageTableForVMA(initial_vma);
+}
+
+VMManager::VMAHandle VMManager::FindVMA(VAddr target) const {
+    return std::prev(vma_map.upper_bound(target));
+}
+
+ResultVal<VMManager::VMAHandle> VMManager::MapMemoryBlock(VAddr target,
+        std::shared_ptr<std::vector<u8>> block, u32 offset, u32 size, MemoryState state) {
+    ASSERT(block != nullptr);
+    ASSERT(offset + size <= block->size());
+
+    // This is the appropriately sized VMA that will turn into our allocation.
+    CASCADE_RESULT(VMAIter vma_handle, CarveVMA(target, size));
+    VirtualMemoryArea& final_vma = vma_handle->second;
+    ASSERT(final_vma.size == size);
+
+    final_vma.type = VMAType::AllocatedMemoryBlock;
+    final_vma.permissions = VMAPermission::ReadWrite;
+    final_vma.meminfo_state = state;
+    final_vma.backing_block = block;
+    final_vma.offset = offset;
+    UpdatePageTableForVMA(final_vma);
+
+    return MakeResult<VMAHandle>(MergeAdjacent(vma_handle));
+}
+
+ResultVal<VMManager::VMAHandle> VMManager::MapBackingMemory(VAddr target, u8 * memory, u32 size, MemoryState state) {
+    ASSERT(memory != nullptr);
+
+    // This is the appropriately sized VMA that will turn into our allocation.
+    CASCADE_RESULT(VMAIter vma_handle, CarveVMA(target, size));
+    VirtualMemoryArea& final_vma = vma_handle->second;
+    ASSERT(final_vma.size == size);
+
+    final_vma.type = VMAType::BackingMemory;
+    final_vma.permissions = VMAPermission::ReadWrite;
+    final_vma.meminfo_state = state;
+    final_vma.backing_memory = memory;
+    UpdatePageTableForVMA(final_vma);
+
+    return MakeResult<VMAHandle>(MergeAdjacent(vma_handle));
+}
+
+ResultVal<VMManager::VMAHandle> VMManager::MapMMIO(VAddr target, PAddr paddr, u32 size, MemoryState state) {
+    // This is the appropriately sized VMA that will turn into our allocation.
+    CASCADE_RESULT(VMAIter vma_handle, CarveVMA(target, size));
+    VirtualMemoryArea& final_vma = vma_handle->second;
+    ASSERT(final_vma.size == size);
+
+    final_vma.type = VMAType::MMIO;
+    final_vma.permissions = VMAPermission::ReadWrite;
+    final_vma.meminfo_state = state;
+    final_vma.paddr = paddr;
+    UpdatePageTableForVMA(final_vma);
+
+    return MakeResult<VMAHandle>(MergeAdjacent(vma_handle));
+}
+
+void VMManager::Unmap(VMAHandle vma_handle) {
+    VMAIter iter = StripIterConstness(vma_handle);
+
+    VirtualMemoryArea& vma = iter->second;
+    vma.type = VMAType::Free;
+    vma.permissions = VMAPermission::None;
+    vma.meminfo_state = MemoryState::Free;
+
+    vma.backing_block = nullptr;
+    vma.offset = 0;
+    vma.backing_memory = nullptr;
+    vma.paddr = 0;
+
+    UpdatePageTableForVMA(vma);
+
+    MergeAdjacent(iter);
+}
+
+void VMManager::Reprotect(VMAHandle vma_handle, VMAPermission new_perms) {
+    VMAIter iter = StripIterConstness(vma_handle);
+
+    VirtualMemoryArea& vma = iter->second;
+    vma.permissions = new_perms;
+    UpdatePageTableForVMA(vma);
+
+    MergeAdjacent(iter);
+}
+
+VMManager::VMAIter VMManager::StripIterConstness(const VMAHandle & iter) {
+    // This uses a neat C++ trick to convert a const_iterator to a regular iterator, given
+    // non-const access to its container.
+    return vma_map.erase(iter, iter); // Erases an empty range of elements
+}
+
+ResultVal<VMManager::VMAIter> VMManager::CarveVMA(VAddr base, u32 size) {
+    ASSERT_MSG((size & Memory::PAGE_MASK) == 0, "non-page aligned size: %8X", size);
+    ASSERT_MSG((base & Memory::PAGE_MASK) == 0, "non-page aligned base: %08X", base);
+
+    VMAIter vma_handle = StripIterConstness(FindVMA(base));
+    if (vma_handle == vma_map.end()) {
+        // Target address is outside the range managed by the kernel
+        return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::OS,
+                ErrorSummary::InvalidArgument, ErrorLevel::Usage); // 0xE0E01BF5
+    }
+
+    VirtualMemoryArea& vma = vma_handle->second;
+    if (vma.type != VMAType::Free) {
+        // Region is already allocated
+        return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::OS,
+                ErrorSummary::InvalidState, ErrorLevel::Usage); // 0xE0A01BF5
+    }
+
+    u32 start_in_vma = base - vma.base;
+    u32 end_in_vma = start_in_vma + size;
+
+    if (end_in_vma > vma.size) {
+        // Requested allocation doesn't fit inside VMA
+        return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::OS,
+                ErrorSummary::InvalidState, ErrorLevel::Usage); // 0xE0A01BF5
+    }
+
+    if (end_in_vma != vma.size) {
+        // Split VMA at the end of the allocated region
+        SplitVMA(vma_handle, end_in_vma);
+    }
+    if (start_in_vma != 0) {
+        // Split VMA at the start of the allocated region
+        vma_handle = SplitVMA(vma_handle, start_in_vma);
+    }
+
+    return MakeResult<VMAIter>(vma_handle);
+}
+
+VMManager::VMAIter VMManager::SplitVMA(VMAIter vma_handle, u32 offset_in_vma) {
+    VirtualMemoryArea& old_vma = vma_handle->second;
+    VirtualMemoryArea new_vma = old_vma; // Make a copy of the VMA
+
+    // For now, don't allow no-op VMA splits (trying to split at a boundary) because it's probably
+    // a bug. This restriction might be removed later.
+    ASSERT(offset_in_vma < old_vma.size);
+    ASSERT(offset_in_vma > 0);
+
+    old_vma.size = offset_in_vma;
+    new_vma.base += offset_in_vma;
+    new_vma.size -= offset_in_vma;
+
+    switch (new_vma.type) {
+    case VMAType::Free:
+        break;
+    case VMAType::AllocatedMemoryBlock:
+        new_vma.offset += offset_in_vma;
+        break;
+    case VMAType::BackingMemory:
+        new_vma.backing_memory += offset_in_vma;
+        break;
+    case VMAType::MMIO:
+        new_vma.paddr += offset_in_vma;
+        break;
+    }
+
+    ASSERT(old_vma.CanBeMergedWith(new_vma));
+
+    return vma_map.emplace_hint(std::next(vma_handle), new_vma.base, new_vma);
+}
+
+VMManager::VMAIter VMManager::MergeAdjacent(VMAIter iter) {
+    VMAIter next_vma = std::next(iter);
+    if (next_vma != vma_map.end() && iter->second.CanBeMergedWith(next_vma->second)) {
+        iter->second.size += next_vma->second.size;
+        vma_map.erase(next_vma);
+    }
+
+    if (iter != vma_map.begin()) {
+        VMAIter prev_vma = std::prev(iter);
+        if (prev_vma->second.CanBeMergedWith(iter->second)) {
+            prev_vma->second.size += iter->second.size;
+            vma_map.erase(iter);
+            iter = prev_vma;
+        }
+    }
+
+    return iter;
+}
+
+void VMManager::UpdatePageTableForVMA(const VirtualMemoryArea& vma) {
+    switch (vma.type) {
+    case VMAType::Free:
+        Memory::UnmapRegion(vma.base, vma.size);
+        break;
+    case VMAType::AllocatedMemoryBlock:
+        Memory::MapMemoryRegion(vma.base, vma.size, vma.backing_block->data() + vma.offset);
+        break;
+    case VMAType::BackingMemory:
+        Memory::MapMemoryRegion(vma.base, vma.size, vma.backing_memory);
+        break;
+    case VMAType::MMIO:
+        // TODO(yuriks): Add support for MMIO handlers.
+        Memory::MapIoRegion(vma.base, vma.size);
+        break;
+    }
+}
+
+}