ExhaustibleBlockDevice.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2017 ARM Limited
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy
00005  * of this software and associated documentation files (the "Software"), to deal
00006  * in the Software without restriction, including without limitation the rights
00007  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008  * copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in
00012  * all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
00020  * SOFTWARE.
00021  */
00022 #ifndef MBED_EXHAUSTIBLE_BLOCK_DEVICE_H
00023 #define MBED_EXHAUSTIBLE_BLOCK_DEVICE_H
00024 
00025 #include "BlockDevice.h"
00026 
00027 
00028 /** Heap backed block device which simulates failures
00029  *
00030  * Similar to heap block device but sectors wear out and are no longer programmable
00031  * after a configurable number of cycles.
00032  *
00033  */
00034 class ExhaustibleBlockDevice : public BlockDevice
00035 {
00036 public:
00037     /** Lifetime of the block device
00038      *
00039      * @param bd            Block device to back the ExhaustibleBlockDevice
00040      * @param erase_cycles  Number of erase cycles before failure
00041      */
00042     ExhaustibleBlockDevice(BlockDevice *bd, uint32_t erase_cycles);
00043     virtual ~ExhaustibleBlockDevice();
00044 
00045     /**
00046      * Get the number of erase cycles remaining on a block
00047      *
00048      * @param addr      Any address in the block being queried for erase cycles
00049      * @return          Number of erase cycles remaining
00050      */
00051     uint32_t get_erase_cycles(bd_addr_t addr) const;
00052 
00053     /**
00054      * Set the number of erase cycles before failure
00055      *
00056      * @param addr      Any address in the block being queried for erase cycles
00057      * @param cycles    Erase cycles before the block malfunctions
00058      */
00059     void set_erase_cycles(bd_addr_t addr, uint32_t cycles);
00060 
00061     /** Initialize a block device
00062      *
00063      *  @return         0 on success or a negative error code on failure
00064      */
00065     virtual int init();
00066 
00067     /** Deinitialize a block device
00068      *
00069      *  @return         0 on success or a negative error code on failure
00070      */
00071     virtual int deinit();
00072 
00073     /** Read blocks from a block device
00074      *
00075      *  @param buffer   Buffer to read blocks into
00076      *  @param addr     Address of block to begin reading from
00077      *  @param size     Size to read in bytes, must be a multiple of read block size
00078      *  @return         0 on success, negative error code on failure
00079      */
00080     virtual int read(void *buffer, bd_addr_t addr, bd_size_t size);
00081 
00082     /** Program blocks to a block device
00083      *
00084      *  The blocks must have been erased prior to being programmed
00085      *
00086      *  @param buffer   Buffer of data to write to blocks
00087      *  @param addr     Address of block to begin writing to
00088      *  @param size     Size to write in bytes, must be a multiple of program block size
00089      *  @return         0 on success, negative error code on failure
00090      */
00091     virtual int program(const void *buffer, bd_addr_t addr, bd_size_t size);
00092 
00093     /** Erase blocks on a block device
00094      *
00095      *  The state of an erased block is undefined until it has been programmed
00096      *
00097      *  @param addr     Address of block to begin erasing
00098      *  @param size     Size to erase in bytes, must be a multiple of erase block size
00099      *  @return         0 on success, negative error code on failure
00100      */
00101     virtual int erase(bd_addr_t addr, bd_size_t size);
00102 
00103     /** Get the size of a readable block
00104      *
00105      *  @return         Size of a readable block in bytes
00106      */
00107     virtual bd_size_t get_read_size() const;
00108 
00109     /** Get the size of a programmable block
00110      *
00111      *  @return         Size of a programmable block in bytes
00112      */
00113     virtual bd_size_t get_program_size() const;
00114 
00115     /** Get the size of a erasable block
00116      *
00117      *  @return         Size of a erasable block in bytes
00118      */
00119     virtual bd_size_t get_erase_size() const;
00120 
00121     /** Get the total size of the underlying device
00122      *
00123      *  @return         Size of the underlying device in bytes
00124      */
00125     virtual bd_size_t size() const;
00126 
00127 private:
00128     BlockDevice *_bd;
00129     uint32_t *_erase_array;
00130     uint32_t _erase_cycles;
00131 };
00132 
00133 
00134 #endif