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 /**
  * @file
  *
  * @ingroup rtems_blkdev
  *
  * @brief Block Device Management
  */
 
 /*
  * Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia
  * Author: Victor V. Vengerov <vvv@oktet.ru>
  */
 
 #ifndef _RTEMS_BLKDEV_H
 #define _RTEMS_BLKDEV_H
 
 #include <rtems.h>
 #include <rtems/diskdevs.h>
 #include <rtems/print.h>
 #include <sys/ioccom.h>
 #include <stdio.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 /**
  * @defgroup rtems_blkdev Block Device Management
  *
  * @ingroup rtems_libblock
  *
  * Interface between device drivers and the
  * @ref rtems_bdbuf "block device buffer module".
  *
  * The heart of the block device driver is the @ref RTEMS_BLKIO_REQUEST IO
  * control. This call puts IO @ref rtems_blkdev_request "requests" to the block
  * device for asynchronous processing. When a driver executes a request, it
  * invokes the request done callback function to finish the request.
  */
 /**@{**/
 
 /**
  * @brief Block device request type.
  *
  * @warning The sync request is an IO one and only used from the cache. Use the
  *          Block IO when operating at the device level. We need a sync request
  *          to avoid requests looping for ever.
  */
 typedef enum rtems_blkdev_request_op {
   RTEMS_BLKDEV_REQ_READ,       /**< Read the requested blocks of data. */
   RTEMS_BLKDEV_REQ_WRITE,      /**< Write the requested blocks of data. */
   RTEMS_BLKDEV_REQ_SYNC        /**< Sync any data with the media. */
 } rtems_blkdev_request_op;
 
 struct rtems_blkdev_request;
 
 /**
  * @brief Block device request done callback function type.
  */
 typedef void (*rtems_blkdev_request_cb)(
   struct rtems_blkdev_request *req,
   rtems_status_code status
 );
 
 /**
  * @brief Block device scatter or gather buffer structure.
  */
 typedef struct rtems_blkdev_sg_buffer {
   /**
    * Block index.
    */
   rtems_blkdev_bnum block;
 
   /**
    * Buffer length.
    */
   uint32_t length;
 
   /**
    * Buffer pointer.
    */
   void *buffer;
 
   /**
    * User pointer.
    */
   void *user;
 } rtems_blkdev_sg_buffer;
 
 /**
  * @brief The block device transfer request is used to read or write a number
  * of blocks from or to the device.
  *
  * Transfer requests are issued to the disk device driver with the
  * @ref RTEMS_BLKIO_REQUEST IO control.  The transfer request completion status
  * must be signalled with rtems_blkdev_request_done().  This function must be
  * called exactly once per request.  The return value of the IO control will be
  * ignored for transfer requests.
  *
  * @see rtems_blkdev_create().
  */
 typedef struct rtems_blkdev_request {
   /**
    * Block device operation (read or write).
    */
   rtems_blkdev_request_op req;
 
   /**
    * Request done callback function.
    */
   rtems_blkdev_request_cb done;
 
   /**
    * Argument to be passed to callback function.
    */
   void *done_arg;
 
   /**
    * Last IO operation completion status.
    */
   rtems_status_code status;
 
   /**
    * Number of blocks for this request.
    */
   uint32_t bufnum;
 
   /**
    * The task requesting the IO operation.
    */
   rtems_id io_task;
 
   /*
    * TODO: The use of these req blocks is not a great design. The req is a
    *       struct with a single 'bufs' declared in the req struct and the
    *       others are added in the outer level struct. This relies on the
    *       structs joining as a single array and that assumes the compiler
    *       packs the structs. Why not just place on a list ? The BD has a
    *       node that can be used.
    */
 
   /**
    * List of scatter or gather buffers.
    */
   rtems_blkdev_sg_buffer bufs[RTEMS_ZERO_LENGTH_ARRAY];
 } rtems_blkdev_request;
 
 /**
  * @brief Signals transfer request completion status.
  *
  * This function must be called exactly once per request.
  *
  * @param[in,out] req The transfer request.
  * @param[in] status The status of the operation should be
  *  - @c RTEMS_SUCCESSFUL, if the operation was successful,
  *  - @c RTEMS_IO_ERROR, if some sort of input or output error occurred, or
  *  - @c RTEMS_UNSATISFIED, if media is no more present.
  */
 static inline void rtems_blkdev_request_done(
   rtems_blkdev_request *req,
   rtems_status_code status
 )
 {
   (*req->done)(req, status);
 }
 
 /**
  * @brief The start block in a request.
  *
  * Only valid if the driver has returned the
  * @ref RTEMS_BLKDEV_CAP_MULTISECTOR_CONT capability.
  */
 #define RTEMS_BLKDEV_START_BLOCK(req) (req->bufs[0].block)
 
 /**
  * @name IO Control Request Codes
  */
 /**@{**/
 
 #define RTEMS_BLKIO_REQUEST         _IOWR('B', 1, rtems_blkdev_request)
 #define RTEMS_BLKIO_GETMEDIABLKSIZE _IOR('B', 2, uint32_t)
 #define RTEMS_BLKIO_GETBLKSIZE      _IOR('B', 3, uint32_t)
 #define RTEMS_BLKIO_SETBLKSIZE      _IOW('B', 4, uint32_t)
 #define RTEMS_BLKIO_GETSIZE         _IOR('B', 5, rtems_blkdev_bnum)
 #define RTEMS_BLKIO_SYNCDEV         _IO('B', 6)
 #define RTEMS_BLKIO_DELETED         _IO('B', 7)
 #define RTEMS_BLKIO_CAPABILITIES    _IO('B', 8)
 #define RTEMS_BLKIO_GETDISKDEV      _IOR('B', 9, rtems_disk_device *)
 #define RTEMS_BLKIO_PURGEDEV        _IO('B', 10)
 #define RTEMS_BLKIO_GETDEVSTATS     _IOR('B', 11, rtems_blkdev_stats *)
 #define RTEMS_BLKIO_RESETDEVSTATS   _IO('B', 12)
 
 /** @} */
 
 static inline int rtems_disk_fd_get_media_block_size(
   int fd,
   uint32_t *media_block_size
 )
 {
   return ioctl(fd, RTEMS_BLKIO_GETMEDIABLKSIZE, media_block_size);
 }
 
 static inline int rtems_disk_fd_get_block_size(int fd, uint32_t *block_size)
 {
   return ioctl(fd, RTEMS_BLKIO_GETBLKSIZE, block_size);
 }
 
 static inline int rtems_disk_fd_set_block_size(int fd, uint32_t block_size)
 {
   return ioctl(fd, RTEMS_BLKIO_SETBLKSIZE, &block_size);
 }
 
 static inline int rtems_disk_fd_get_block_count(
   int fd,
   rtems_blkdev_bnum *block_count
 )
 {
   return ioctl(fd, RTEMS_BLKIO_GETSIZE, block_count);
 }
 
 static inline int rtems_disk_fd_get_disk_device(
   int fd,
   rtems_disk_device **dd_ptr
 )
 {
   return ioctl(fd, RTEMS_BLKIO_GETDISKDEV, dd_ptr);
 }
 
 static inline int rtems_disk_fd_sync(int fd)
 {
   return ioctl(fd, RTEMS_BLKIO_SYNCDEV);
 }
 
 static inline int rtems_disk_fd_purge(int fd)
 {
   return ioctl(fd, RTEMS_BLKIO_PURGEDEV);
 }
 
 static inline int rtems_disk_fd_get_device_stats(
   int fd,
   rtems_blkdev_stats *stats
 )
 {
   return ioctl(fd, RTEMS_BLKIO_GETDEVSTATS, stats);
 }
 
 static inline int rtems_disk_fd_reset_device_stats(int fd)
 {
   return ioctl(fd, RTEMS_BLKIO_RESETDEVSTATS);
 }
 
 /**
  * @name Block Device Driver Capabilities
  */
 /**@{**/
 
 /**
  * @brief Only consecutive multi-sector buffer requests are supported.
  *
  * This option means the cache will only supply multiple buffers that are
  * inorder so the ATA multi-sector command for example can be used. This is a
  * hack to work around the current ATA driver.
  */
 #define RTEMS_BLKDEV_CAP_MULTISECTOR_CONT (1 << 0)
 
 /**
  * @brief The driver will accept a sync call.
  *
  * A sync call is made to a driver after a bdbuf cache sync has finished.
  */
 #define RTEMS_BLKDEV_CAP_SYNC (1 << 1)
 
 /** @} */
 
 /**
  * @brief Common IO control primitive.
  *
  * Use this in all block devices to handle the common set of IO control
  * requests.
  */
 int
 rtems_blkdev_ioctl(rtems_disk_device *dd, uint32_t req, void *argp);
 
 /**
  * @brief Creates a block device.
  *
  * The block size is set to the media block size.
  *
  * @param[in] device The path for the new block device.
  * @param[in] media_block_size The media block size in bytes.  Must be positive.
  * @param[in] media_block_count The media block count.  Must be positive.
  * @param[in] handler The block device IO control handler.  Must not be @c NULL.
  * @param[in] driver_data The block device driver data.
  *
  * @retval RTEMS_SUCCESSFUL Successful operation.
  * @retval RTEMS_INVALID_NUMBER Media block size or count is not positive.
  * @retval RTEMS_NO_MEMORY Not enough memory.
  * @retval RTEMS_UNSATISFIED Cannot create generic device node.
  * @retval RTEMS_INCORRECT_STATE Cannot initialize bdbuf.
  *
  * @see rtems_blkdev_create_partition(), rtems_bdbuf_set_block_size(), and
  * rtems_blkdev_request.
  */
 rtems_status_code rtems_blkdev_create(
   const char *device,
   uint32_t media_block_size,
   rtems_blkdev_bnum media_block_count,
   rtems_block_device_ioctl handler,
   void *driver_data
 );
 
 /**
  * @brief Creates a partition within a parent block device.
  *
  * A partition manages a subset of consecutive blocks contained in a parent block
  * device.  The blocks must be within the range of blocks managed by the
  * associated parent block device.  The media block size and IO control
  * handler are inherited by the parent block device.  The block size is set to
  * the media block size.
  *
  * @param[in] partition The path for the new partition device.
  * @param[in] parent_block_device The parent block device path.
  * @param[in] media_block_begin The media block begin of the partition within
  * the parent block device.
  * @param[in] media_block_count The media block count of the partition.
  *
  * @retval RTEMS_SUCCESSFUL Successful operation.
  * @retval RTEMS_INVALID_ID Block device node does not exist.
  * @retval RTEMS_INVALID_NODE File system node is not a block device.
  * @retval RTEMS_NOT_IMPLEMENTED Block device implementation is incomplete.
  * @retval RTEMS_INVALID_NUMBER Block begin or block count is invalid.
  * @retval RTEMS_NO_MEMORY Not enough memory.
  * @retval RTEMS_UNSATISFIED Cannot create generic device node.
  *
  * @see rtems_blkdev_create() and rtems_bdbuf_set_block_size().
  */
 rtems_status_code rtems_blkdev_create_partition(
   const char *partition,
   const char *parent_block_device,
   rtems_blkdev_bnum media_block_begin,
   rtems_blkdev_bnum media_block_count
 );
 
 /**
  * @brief Prints the block device statistics.
  */
 void rtems_blkdev_print_stats(
   const rtems_blkdev_stats *stats,
   uint32_t media_block_size,
   uint32_t media_block_count,
   uint32_t block_size,
   const rtems_printer* printer
 );
 
 /**
  * @brief Block device statistics command.
  */
 void rtems_blkstats(
   const rtems_printer *printer,
   const char *device,
   bool reset
 );
 
 /** @} */
 
 /**
  * @defgroup rtems_blkdev_generic Generic Disk Device
  *
  * @ingroup rtems_blkdev
  *
  * Generic disk device operations for standard RTEMS IO drivers.
  */
 /**@{**/
 
 /**
  * The device driver interface conventions suppose that a driver may contain an
  * initialize, open, close, read, write and IO control entry points. These
  * primitives (except initialize) can be implemented in a generic fashion based
  * upon the supplied block device driver IO control handler. Every block device
  * driver should provide an initialize entry point, which registers the
  * appropriate IO control handler.
  */
 #define RTEMS_GENERIC_BLOCK_DEVICE_DRIVER_ENTRIES \
   rtems_blkdev_generic_open, \
   rtems_blkdev_generic_close, \
   rtems_blkdev_generic_read, \
   rtems_blkdev_generic_write, \
   rtems_blkdev_generic_ioctl
 
 /* Use rtems_blkdev_create() instead */
 RTEMS_DEPRECATED rtems_device_driver
 rtems_blkdev_generic_read(
     rtems_device_major_number major,
     rtems_device_minor_number minor,
     void                    * arg
 );
 
 /* Use rtems_blkdev_create() instead */
 RTEMS_DEPRECATED rtems_device_driver
 rtems_blkdev_generic_write(
     rtems_device_major_number major,
     rtems_device_minor_number minor,
     void                    * arg
 );
 
 /* Use rtems_blkdev_create() instead */
 RTEMS_DEPRECATED rtems_device_driver
 rtems_blkdev_generic_open(
     rtems_device_major_number major,
     rtems_device_minor_number minor,
     void                    * arg
 );
 
 /* Use rtems_blkdev_create() instead */
 RTEMS_DEPRECATED rtems_device_driver
 rtems_blkdev_generic_close(
     rtems_device_major_number major,
     rtems_device_minor_number minor,
     void                    * arg
 );
 
 /* Use rtems_blkdev_create() instead */
 RTEMS_DEPRECATED rtems_device_driver
 rtems_blkdev_generic_ioctl(
     rtems_device_major_number major,
     rtems_device_minor_number minor,
     void                    * arg
 );
 
 /* Use rtems_blkdev_create() instead */
 RTEMS_DEPRECATED extern const rtems_driver_address_table rtems_blkdev_generic_ops;
 
 /** @} */
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif

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