Nicolas Borla
/
BBR_1Ebene
BBR 1 Ebene
Diff: mbed-os/features/filesystem/bd/SlicingBlockDevice.h
- Revision:
- 0:fbdae7e6d805
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-os/features/filesystem/bd/SlicingBlockDevice.h Mon May 14 11:29:06 2018 +0000 @@ -0,0 +1,171 @@ +/* mbed Microcontroller Library + * Copyright (c) 2017 ARM Limited + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ +#ifndef MBED_SLICING_BLOCK_DEVICE_H +#define MBED_SLICING_BLOCK_DEVICE_H + +#include "BlockDevice.h" +#include "mbed.h" + + +/** Block device for mapping to a slice of another block device + * + * @code + * #include "mbed.h" + * #include "HeapBlockDevice.h" + * #include "SlicingBlockDevice.h" + * + * // Create a block device with 64 blocks of size 512 + * HeapBlockDevice mem(64*512, 512); + * + * // Create a block device that maps to the first 32 blocks + * SlicingBlockDevice slice1(&mem, 0*512, 32*512); + * + * // Create a block device that maps to the last 32 blocks + * SlicingBlockDevice slice2(&mem, 32*512); + * + * // Create a block device that maps to the middle 32 blocks + * SlicingBlockDevice slice3(&mem, 16*512, -16*512); + * @endcode + */ +class SlicingBlockDevice : public BlockDevice +{ +public: + /** Lifetime of the memory block device + * + * @param bd Block device to back the SlicingBlockDevice + * @param start Start block address to map to block 0, negative addresses + * are calculated from the end of the underlying block device + * @param end End block address to mark the end of the block device, + * this block is not mapped, negative addresses are + * calculated from the end of the underlying block device. + * The default stops at end of the underlying block device. + */ + SlicingBlockDevice(BlockDevice *bd, bd_addr_t start, bd_addr_t end = 0); + + /** Lifetime of a block device + */ + virtual ~SlicingBlockDevice() {}; + + /** 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, 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, 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, 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; + +protected: + BlockDevice *_bd; + bool _start_from_end; + bd_size_t _start; + bool _stop_from_end; + bd_size_t _stop; +}; + + +#endif