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Diffstat (limited to 'os/various/ramdisk.c')
| -rw-r--r-- | os/various/ramdisk.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/os/various/ramdisk.c b/os/various/ramdisk.c new file mode 100644 index 0000000..23bf658 --- /dev/null +++ b/os/various/ramdisk.c @@ -0,0 +1,219 @@ +/* + ChibiOS/HAL - Copyright (C) 2016 Uladzimir Pylinsky aka barthess + + 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. +*/ + +/** + * @file ramdisk.c + * @brief Virtual block devise driver source. + * + * @addtogroup ramdisk + * @{ + */ + +#include "hal.h" + +#include "ramdisk.h" + +#include <string.h> + +/*===========================================================================*/ +/* Driver local definitions. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver exported variables. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver local variables. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver local functions. */ +/*===========================================================================*/ + +/* + * Interface implementation. + */ +static bool overflow(const RamDisk *rd, uint32_t startblk, uint32_t n) { + return (startblk + n) > rd->blk_num; +} + +static bool is_inserted(void *instance) { + (void)instance; + return true; +} + +static bool is_protected(void *instance) { + RamDisk *rd = instance; + if (BLK_READY == rd->state) { + return rd->readonly; + } + else { + return true; + } +} + +static bool connect(void *instance) { + RamDisk *rd = instance; + if (BLK_STOP == rd->state) { + rd->state = BLK_READY; + } + return HAL_SUCCESS; +} + +static bool disconnect(void *instance) { + RamDisk *rd = instance; + if (BLK_STOP != rd->state) { + rd->state = BLK_STOP; + } + return HAL_SUCCESS; +} + +static bool read(void *instance, uint32_t startblk, + uint8_t *buffer, uint32_t n) { + + RamDisk *rd = instance; + + if (overflow(rd, startblk, n)) { + return HAL_FAILED; + } + else { + const uint32_t bs = rd->blk_size; + memcpy(buffer, &rd->storage[startblk * bs], n * bs); + return HAL_SUCCESS; + } +} + +static bool write(void *instance, uint32_t startblk, + const uint8_t *buffer, uint32_t n) { + + RamDisk *rd = instance; + if (overflow(rd, startblk, n)) { + return HAL_FAILED; + } + else { + const uint32_t bs = rd->blk_size; + memcpy(&rd->storage[startblk * bs], buffer, n * bs); + return HAL_SUCCESS; + } +} + +static bool sync(void *instance) { + + RamDisk *rd = instance; + if (BLK_READY != rd->state) { + return HAL_FAILED; + } + else { + return HAL_SUCCESS; + } +} + +static bool get_info(void *instance, BlockDeviceInfo *bdip) { + + RamDisk *rd = instance; + if (BLK_READY != rd->state) { + return HAL_FAILED; + } + else { + bdip->blk_num = rd->blk_num; + bdip->blk_size = rd->blk_size; + return HAL_SUCCESS; + } +} + +/** + * + */ +static const struct BaseBlockDeviceVMT vmt = { + is_inserted, + is_protected, + connect, + disconnect, + read, + write, + sync, + get_info +}; + +/*===========================================================================*/ +/* Driver interrupt handlers. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver exported functions. */ +/*===========================================================================*/ + +/** + * @brief RAM disk object initialization. + * + * @param[in] rdp pointer to @p RamDisk object + * + * @init + */ +void ramdiskObjectInit(RamDisk *rdp) { + + rdp->vmt = &vmt; + rdp->state = BLK_STOP; +} + +/** + * @brief Starts RAM disk. + * + * @param[in] rdp pointer to @p RamDisk object + * @param[in] storage pointer to array representing disk storage + * @param[in] blksize size of blocks in bytes + * @param[in] blknum total number of blocks in device + * @param[in] readonly read only flag + * + * @api + */ +void ramdiskStart(RamDisk *rdp, uint8_t *storage, uint32_t blksize, + uint32_t blknum, bool readonly) { + + osalDbgCheck(rdp != NULL); + + osalSysLock(); + osalDbgAssert((rdp->state == BLK_STOP) || (rdp->state == BLK_READY), + "invalid state"); + rdp->blk_num = blknum; + rdp->blk_size = blksize; + rdp->readonly = readonly; + rdp->storage = storage; + rdp->state = BLK_READY; + osalSysUnlock(); +} + +/** + * @brief Stops RAM disk. + * + * @param[in] rdp pointer to @p RamDisk object + * + * @api + */ +void ramdiskStop(RamDisk *rdp) { + + osalDbgCheck(rdp != NULL); + + osalSysLock(); + osalDbgAssert((rdp->state == BLK_STOP) || (rdp->state == BLK_READY), + "invalid state"); + rdp->storage = NULL; + rdp->state = BLK_STOP; + osalSysUnlock(); +} + +/** @} */ |