// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "address_space_base.h"

bool AddressSpaceBase::AddMapping(std::unique_ptr<GpuMapping> gpu_mapping)
{
    auto iter = mappings_.upper_bound(gpu_mapping->gpu_addr());
    if (iter != mappings_.end() &&
        (gpu_mapping->gpu_addr() + gpu_mapping->page_count() * PAGE_SIZE >
         iter->second->gpu_addr()))
        return DRETF(false, "Mapping overlaps existing mapping");
    // Find the mapping with the highest VA that's <= this.
    if (iter != mappings_.begin()) {
        --iter;
        // Check if the previous mapping overlaps this.
        if (iter->second->gpu_addr() + iter->second->page_count() * PAGE_SIZE >
            gpu_mapping->gpu_addr())
            return DRETF(false, "Mapping overlaps existing mapping");
    }

    if (!Insert(gpu_mapping->gpu_addr(), gpu_mapping->bus_mapping(), gpu_mapping->page_count()))
        return DRETF(false, "failed to insert mapping");

    auto platform_buffer = gpu_mapping->buffer()->platform_buffer();

    std::pair<map_container_t::iterator, bool> result =
        mappings_.insert({gpu_mapping->gpu_addr(), std::move(gpu_mapping)});
    DASSERT(result.second);

    mappings_by_buffer_.insert({platform_buffer, result.first});

    return true;
}

bool AddressSpaceBase::RemoveMapping(magma::PlatformBuffer* buffer, gpu_addr_t gpu_addr)
{
    auto range = mappings_by_buffer_.equal_range(buffer);
    for (auto iter = range.first; iter != range.second; iter++) {
        std::shared_ptr<GpuMapping> gpu_mapping = iter->second->second;
        if (gpu_mapping->gpu_addr() == gpu_addr) {
            mappings_.erase(iter->second);
            mappings_by_buffer_.erase(iter);
            return true;
        }
    }
    return DRETF(false, "failed to remove mapping");
}

void AddressSpaceBase::ReleaseBuffer(magma::PlatformBuffer* buffer, uint32_t* released_count_out)
{
    *released_count_out = 0;
    auto range = mappings_by_buffer_.equal_range(buffer);
    for (auto iter = range.first; iter != range.second;) {
        mappings_.erase(iter->second);
        iter = mappings_by_buffer_.erase(iter);
        *released_count_out += 1;
    }
}