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Diffstat (limited to 'include/rtems/sparse-disk.h')
| -rw-r--r-- | include/rtems/sparse-disk.h | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/include/rtems/sparse-disk.h b/include/rtems/sparse-disk.h new file mode 100644 index 0000000000..e558e08925 --- /dev/null +++ b/include/rtems/sparse-disk.h @@ -0,0 +1,137 @@ +/** + * @file + * + * @ingroup rtems_sparse_disk + * + * @brief Sparse disk block device API. + */ + +/* + * Copyright (c) 2012 embedded brains GmbH. All rights reserved. + * + * embedded brains GmbH + * Obere Lagerstr. 30 + * 82178 Puchheim + * Germany + * <rtems@embedded-brains.de> + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.org/license/LICENSE. + */ + +#ifndef SPARSE_DISK_H +#define SPARSE_DISK_H + +#include <stddef.h> +#include <stdint.h> +#include <rtems.h> +#include <rtems/diskdevs.h> + +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ + +/** + * @defgroup rtems_sparse_disk Sparse Disk Device + * + * @ingroup rtems_blkdev + * + */ +/**@{**/ + +typedef struct { + rtems_blkdev_bnum block; + void *data; +} rtems_sparse_disk_key; + +typedef struct rtems_sparse_disk rtems_sparse_disk; + +typedef void (*rtems_sparse_disk_delete_handler)(rtems_sparse_disk *sparse_disk); + +struct rtems_sparse_disk { + rtems_id mutex; + rtems_blkdev_bnum blocks_with_buffer; + size_t used_count; + uint32_t media_block_size; + rtems_sparse_disk_delete_handler delete_handler; + uint8_t fill_pattern; + rtems_sparse_disk_key *key_table; +}; + +/** + * @brief Creates and registers a sparse disk. + * + * @param[in] device_file_name The device file name path. + * @param[in] media_block_size The media block size in bytes. + * @param[in] blocks_with_buffer Blocks of the device with a buffer. Other + * blocks can store only fill pattern value bytes. + * @param[in] block_count The media block count of the device. It is the sum + * of blocks with buffer and blocks that contain only fill pattern value bytes. + * @param[in] fill_pattern The fill pattern specifies the byte value of blocks + * without a buffer. It is also the initial value for blocks with a buffer. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_NUMBER Media block size or media block count is not + * positive. The blocks with buffer count is greater than the media block count. + * @retval RTEMS_NO_MEMORY Not enough memory. + * @retval RTEMS_TOO_MANY Cannot create semaphore. + * @retval RTEMS_UNSATISFIED Cannot create generic device node. + * + * @see rtems_sparse_disk_register(). + */ +rtems_status_code rtems_sparse_disk_create_and_register( + const char *device_file_name, + uint32_t media_block_size, + rtems_blkdev_bnum blocks_with_buffer, + rtems_blkdev_bnum media_block_count, + uint8_t fill_pattern +); + +/** + * @brief Frees a sparse disk. + * + * Calls free() on the sparse disk pointer. + */ +void rtems_sparse_disk_free( rtems_sparse_disk *sparse_disk ); + +/** + * @brief Initializes and registers a sparse disk. + * + * This will create one semaphore for mutual exclusion. + * + * @param[in] device_file_name The device file name path. + * @param[in, out] sparse_disk The sparse disk. + * @param[in] media_block_size The media block size in bytes. + * @param[in] blocks_with_buffer Blocks of the device with a buffer. Other + * blocks can store only fill pattern value bytes. + * @param[in] block_count The media block count of the device. It is the sum + * of blocks with buffer and blocks that contain only fill pattern value bytes. + * @param[in] fill_pattern The fill pattern specifies the byte value of blocks + * without a buffer. It is also the initial value for blocks with a buffer. + * @param[in] sparse_disk_delete The sparse disk delete handler. + * + * @retval RTEMS_SUCCESSFUL Successful operation. + * @retval RTEMS_INVALID_NUMBER Media block size or media block count is not + * positive. The blocks with buffer count is greater than the media block count. + * @retval RTEMS_INVALID_ADDRESS Invalid sparse disk address. + * @retval RTEMS_TOO_MANY Cannot create semaphore. + * @retval RTEMS_UNSATISFIED Cannot create generic device node. + */ +rtems_status_code rtems_sparse_disk_register( + const char *device_file_name, + rtems_sparse_disk *sparse_disk, + uint32_t media_block_size, + rtems_blkdev_bnum blocks_with_buffer, + rtems_blkdev_bnum media_block_count, + uint8_t fill_pattern, + rtems_sparse_disk_delete_handler sparse_disk_delete +); + +/** @} */ + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + +#endif /* SPARSE_DISK_H */ |