zircon/system/ulib/minfs/allocator/metadata.cpp

// Copyright 2019 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 <utility>

#include "metadata.h"

namespace minfs {

AllocatorFvmMetadata::AllocatorFvmMetadata() = default;
AllocatorFvmMetadata::AllocatorFvmMetadata(uint32_t* data_slices,
                                           uint32_t* metadata_slices,
                                           uint64_t slice_size) :
        data_slices_(data_slices), metadata_slices_(metadata_slices),
        slice_size_(slice_size) {}
AllocatorFvmMetadata::AllocatorFvmMetadata(AllocatorFvmMetadata&&) = default;
AllocatorFvmMetadata& AllocatorFvmMetadata::operator=(AllocatorFvmMetadata&&) = default;
AllocatorFvmMetadata::~AllocatorFvmMetadata() = default;

uint32_t AllocatorFvmMetadata::UnitsPerSlices(uint32_t slices, uint32_t unit_size) const {
    uint64_t units = (slice_size_ * slices) / unit_size;
    ZX_DEBUG_ASSERT(units <= std::numeric_limits<uint32_t>::max());
    return static_cast<uint32_t>(units);
}

// NOTE: This helper is only intended to be called for
// values of |blocks| which are known to be convertible to slices
// without loss. This is checked by a runtime assertion.
uint32_t AllocatorFvmMetadata::BlocksToSlices(uint32_t blocks) const {
    const size_t kBlocksPerSlice = slice_size_ / kMinfsBlockSize;
    uint32_t slices = static_cast<uint32_t>(blocks / kBlocksPerSlice);
    ZX_DEBUG_ASSERT(UnitsPerSlices(slices, kMinfsBlockSize) == blocks);
    return slices;
}

AllocatorMetadata::AllocatorMetadata() = default;
AllocatorMetadata::AllocatorMetadata(blk_t data_start_block,
                                     blk_t metadata_start_block, bool using_fvm,
                                     AllocatorFvmMetadata fvm,
                                     uint32_t* pool_used, uint32_t* pool_total) :
    data_start_block_(data_start_block), metadata_start_block_(metadata_start_block),
    using_fvm_(using_fvm), fvm_(std::move(fvm)),
    pool_used_(pool_used), pool_total_(pool_total) {}
AllocatorMetadata::AllocatorMetadata(AllocatorMetadata&&) = default;
AllocatorMetadata& AllocatorMetadata::operator=(AllocatorMetadata&&) = default;
AllocatorMetadata::~AllocatorMetadata() = default;

} // namespace minfs