1 files changed, 276 insertions, 0 deletions
diff --git a/cpukit/libblock/include/rtems/blkdev.h b/cpukit/libblock/include/rtems/blkdev.h
new file mode 100644
index 0000000000..e9fa86b248
--- /dev/null
+++ b/cpukit/libblock/include/rtems/blkdev.h
@@ -0,0 +1,276 @@
+/**
+ * @file
+ *
+ * @ingroup rtems_blkdev
+ *
+ * Block device management.
+ */
+
+/*
+ * Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia
+ * Author: Victor V. Vengerov <vvv@oktet.ru>
+ *
+ * @(#) $Id$
+ */
+
+#ifndef _RTEMS_BLKDEV_H
+#define _RTEMS_BLKDEV_H
+
+#include <rtems.h>
+#include <rtems/diskdevs.h>
+#include <sys/ioctl.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.
+ *
+ * @{
+ */
+
+/**
+ * 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;
+
+/**
+ * @brief Block device request done callback function type.
+ *
+ * The first parameter @a arg must be the argument provided by the block device
+ * request structure @ref rtems_blkdev_request.
+ *
+ * The second parameter @a status should contain the status of the operation:
+ *  - @c RTEMS_SUCCESSFUL Operation was successful.
+ *  - @c RTEMS_IO_ERROR Some sort of input or output error.
+ *  - @c RTEMS_UNSATISFIED Media no more present.
+ */
+typedef void (*rtems_blkdev_request_cb)(void *arg, rtems_status_code status);
+
+/**
+ * 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;
+
+/**
+ * The block device request structure is used to read or write a number of
+ * blocks from or to the device.
+ *
+ * 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.
+ */
+typedef struct rtems_blkdev_request {
+  /**
+   * Block device operation (read or write).
+   */
+  rtems_blkdev_request_op req;
+
+  /**
+   * Request done callback function.
+   */
+  rtems_blkdev_request_cb req_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;
+
+  /**
+   * List of scatter or gather buffers.
+   */
+  rtems_blkdev_sg_buffer bufs[0];
+} rtems_blkdev_request;
+
+/**
+ * The start block in a request.
+ *
+ * Only valid if the driver has returned the @ref RTEMS_BLKIO_CAPABILITIES of
+ * @ref RTEMS_BLKDEV_CAP_MULTISECTOR_CONT.
+ */
+#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)
+
+/** @} */
+
+/**
+ * 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)
+
+/**
+ * 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)
+
+/**
+ * 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
+
+/**
+ * Generic block device read primitive.
+ *
+ * Implemented using block device buffer management primitives.
+ */
+rtems_device_driver
+rtems_blkdev_generic_read(
+    rtems_device_major_number major,
+    rtems_device_minor_number minor,
+    void                    * arg
+);
+
+/**
+ * Generic block device write primitive.
+ *
+ * Implemented using block device buffer management primitives.
+ */
+rtems_device_driver
+rtems_blkdev_generic_write(
+    rtems_device_major_number major,
+    rtems_device_minor_number minor,
+    void                    * arg
+);
+
+/**
+ * Generic block device open primitive.
+ *
+ * Implemented using block device buffer management primitives.
+ */
+rtems_device_driver
+rtems_blkdev_generic_open(
+    rtems_device_major_number major,
+    rtems_device_minor_number minor,
+    void                    * arg
+);
+
+/**
+ * Generic block device close primitive.
+ *
+ * Implemented using block device buffer management primitives.
+ */
+rtems_device_driver
+rtems_blkdev_generic_close(
+    rtems_device_major_number major,
+    rtems_device_minor_number minor,
+    void                    * arg
+);
+
+/**
+ * Generic block device IO control primitive.
+ *
+ * Implemented using block device buffer management primitives.
+ */
+rtems_device_driver
+rtems_blkdev_generic_ioctl(
+    rtems_device_major_number major,
+    rtems_device_minor_number minor,
+    void                    * arg
+);
+
+/**
+ * Common IO control primitive.
+ *
+ * Use this in all block devices to handle the common set of ioctl requests.
+ */
+int
+rtems_blkdev_ioctl(rtems_disk_device *dd, uint32_t req, void *argp);
+
+/**
+ * @brief Generic block operations driver address table.
+ */
+extern const rtems_driver_address_table rtems_blkdev_generic_ops;
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif