Mbed OS Reference | MBRBlockDevice.h Source File

 /* mbed Microcontroller Library
  * Copyright (c) 2017-2020 ARM Limited
  * SPDX-License-Identifier: Apache-2.0
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 
 /** \addtogroup storage */
 /** @{*/
 
 #ifndef MBED_MBR_BLOCK_DEVICE_H
 #define MBED_MBR_BLOCK_DEVICE_H
 
 #include "BlockDevice.h"
 
 namespace mbed {
 
 /** Additional error codes used for MBR records
  */
 enum {
     BD_ERROR_INVALID_MBR       = -3101,
     BD_ERROR_INVALID_PARTITION = -3102,
 };
 
 
 /** Block device for managing a Master Boot Record
  *  https://en.wikipedia.org/wiki/Master_boot_record
  *
  *  @note
  *  The MBR partition table is relatively limited:
  *  - At most 4 partitions are supported
  *  - Extended partitions are currently not supported and will error during init
  */
 class MBRBlockDevice : public BlockDevice {
 public:
     /** Format the MBR to contain the following partition
      *
      *  @param bd       Block device to partition
      *  @param part     Partition to use, 1-4
      *  @param type     8-bit partition type to specify the filesystem to use in this partition.
      *                  It can be found in the filesystem documentation or refer to
      *                  https://en.wikipedia.org/wiki/Partition_type#List_of_partition_IDs
      *  @param start    Start block address to map to block 0 of partition.
      *                  Negative addresses are calculated from the end of the
      *                  underlying block devices. Block 0 is implicitly ignored
      *                  from the range to store the MBR.
      *  @return         0 on success or a negative error code on failure.
      *  @note This is the same as partition(bd, part, type, start, bd->size())
      */
     static int partition(BlockDevice *bd, int part, uint8_t type, bd_addr_t start);
 
     /** Format the MBR to contain the following partition
      *
      *  @param bd       Block device to partition
      *  @param part     Partition to use, 1-4
      *  @param type     8-bit partition type to specify the filesystem to use in this partition.
      *                  It can be found in the filesystem documentation or refer to
      *                  https://en.wikipedia.org/wiki/Partition_type#List_of_partition_IDs
      *  @param start    Start block address to map to block 0 of partition,
      *                  negative addresses are calculated from the end of the
      *                  underlying block devices. Block 0 is implicitly ignored
      *                  from the range to store the MBR.
      *  @param stop     End block address to mark the end of the partition.
      *                  This block is not mapped: negative addresses are calculated
      *                  from the end of the underlying block device.
      *  @return         0 on success or a negative error code on failure.
      */
     static int partition(BlockDevice *bd, int part, uint8_t type, bd_addr_t start, bd_addr_t stop);
 
     /** Lifetime of the block device
      *
      *  @param bd       Block device to back the MBRBlockDevice
      *  @param part     Partition to use, 1-4
      */
     MBRBlockDevice(BlockDevice *bd, int part);
 
     /** Lifetime of the block device
      */
     virtual ~MBRBlockDevice() {};
 
     /** Initialize a block device
      *
      *  @return         0 on success or a negative error code on failure
      */
     virtual int init();
 
     /** Deinitialize a block device
      *
      *  @return         0 on success or a negative error code on failure
      */
     virtual int deinit();
 
     /** Ensure data on storage is in sync with the driver
      *
      *  @return         0 on success or a negative error code on failure
      */
     virtual int sync();
 
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to read blocks into
      *  @param addr     Address of block to begin reading from
      *  @param size     Size to read in bytes, must be a multiple of read block size
      *  @return         0 on success or a negative error code on failure
      */
     virtual int read(void *buffer, bd_addr_t addr, bd_size_t size);
 
     /** Program blocks to a block device
      *
      *  The blocks must have been erased prior to being programmed
      *
      *  @param buffer   Buffer of data to write to blocks
      *  @param addr     Address of block to begin writing to
      *  @param size     Size to write in bytes, must be a multiple of program block size
      *  @return         0 on success or a negative error code on failure
      */
     virtual int program(const void *buffer, bd_addr_t addr, bd_size_t size);
 
     /** Erase blocks on a block device
      *
      *  The state of an erased block is undefined until it has been programmed,
      *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
      *  @return         0 on success or a negative error code on failure
      */
     virtual int erase(bd_addr_t addr, bd_size_t size);
 
     /** Get the size of a readable block
      *
      *  @return         Size of a readable block in bytes
      */
     virtual bd_size_t get_read_size() const;
 
     /** Get the size of a programmable block
      *
      *  @return         Size of a programmable block in bytes
      *  @note Must be a multiple of the read size
      */
     virtual bd_size_t get_program_size() const;
 
     /** Get the size of an erasable block
      *
      *  @return         Size of an erasable block in bytes
      *  @note Must be a multiple of the program size
      */
     virtual bd_size_t get_erase_size() const;
 
     /** Get the size of an erasable block given address
      *
      *  @param addr     Address within the erasable block
      *  @return         Size of an erasable block in bytes
      *  @note Must be a multiple of the program size
      */
     virtual bd_size_t get_erase_size(bd_addr_t addr) const;
 
     /** Get the value of storage when erased
      *
      *  If get_erase_value returns a non-negative byte value, the underlying
      *  storage is set to that value when erased, and storage containing
      *  that value can be programmed without another erase.
      *
      *  @return         The value of storage when erased, or -1 if you can't
      *                  rely on the value of erased storage
      */
     virtual int get_erase_value() const;
 
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes
      */
     virtual bd_size_t size() const;
 
     /** Get the offset of the partition on the underlying block device
      *  @return         Offset of the partition on the underlying device
      */
     virtual bd_addr_t get_partition_start() const;
 
     /** Get size of partition on underlying block device
      *  @return         Size of the partition on the underlying device
      */
     virtual bd_addr_t get_partition_stop() const;
 
     /** Get 8-bit type of the partition
      *  @return         8-bit type of partition assigned during format
      */
     virtual uint8_t get_partition_type() const;
 
     /** Get the partition number
      *  @return         The partition number, 1-4
      */
     virtual int get_partition_number() const;
 
     /** Get the BlockDevice class type.
      *
      *  @return         A string represent the BlockDevice class type.
      */
     virtual const char *get_type() const;
 
 protected:
     BlockDevice *_bd;
     bd_size_t _offset;
     bd_size_t _size;
     uint8_t _type;
     uint8_t _part;
     uint32_t _init_ref_count;
     bool _is_initialized;
 };
 
 } // namespace mbed
 
 // Added "using" for backwards compatibility
 #ifndef MBED_NO_GLOBAL_USING_DIRECTIVE
 using mbed::MBRBlockDevice;
 #endif
 
 #endif
 
 /** @}*/
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