1 | /* |
---|
2 | * blkdev.h - block device driver interface definitions |
---|
3 | * |
---|
4 | * Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia |
---|
5 | * Author: Victor V. Vengerov <vvv@oktet.ru> |
---|
6 | * |
---|
7 | * @(#) $Id$ |
---|
8 | */ |
---|
9 | |
---|
10 | #ifndef __RTEMS_LIBBLOCK_BLKDEV_H__ |
---|
11 | #define __RTEMS_LIBBLOCK_BLKDEV_H__ |
---|
12 | |
---|
13 | #include <rtems.h> |
---|
14 | #include <sys/ioctl.h> |
---|
15 | |
---|
16 | #ifdef __cplusplus |
---|
17 | extern "C" { |
---|
18 | #endif |
---|
19 | |
---|
20 | /* Interface with device drivers |
---|
21 | * Block device looks, initialized and behaves like traditional RTEMS device |
---|
22 | * driver. Heart of the block device driver is in BIOREQUEST ioctl. This call |
---|
23 | * puts I/O request to the block device queue, in priority order, for |
---|
24 | * asynchronous processing. When driver executes request, req_done |
---|
25 | * function invoked, so callee knows about it. Look for details below. |
---|
26 | */ |
---|
27 | |
---|
28 | |
---|
29 | /* Block device block number datatype */ |
---|
30 | typedef rtems_unsigned32 blkdev_bnum; |
---|
31 | |
---|
32 | /* Block device request type */ |
---|
33 | typedef enum blkdev_request_op { |
---|
34 | BLKDEV_REQ_READ, /* Read operation */ |
---|
35 | BLKDEV_REQ_WRITE /* Write operation */ |
---|
36 | } blkdev_request_op; |
---|
37 | |
---|
38 | /* Type for block device request done callback function. |
---|
39 | * |
---|
40 | * PARAMETERS: |
---|
41 | * arg - argument supplied in blkdev_request |
---|
42 | * status - rtems status code for this operation |
---|
43 | * errno - errno value to be passed to the user when |
---|
44 | * status != RTEMS_SUCCESSFUL |
---|
45 | */ |
---|
46 | typedef void (* blkdev_request_cb)(void *arg, |
---|
47 | rtems_status_code status, |
---|
48 | int error); |
---|
49 | |
---|
50 | /* blkdev_sg_buffer |
---|
51 | * Block device scatter/gather buffer structure |
---|
52 | */ |
---|
53 | typedef struct blkdev_sg_buffer { |
---|
54 | rtems_unsigned32 length; /* Buffer length */ |
---|
55 | void *buffer; /* Buffer pointer */ |
---|
56 | } blkdev_sg_buffer; |
---|
57 | |
---|
58 | /* blkdev_request (Block Device Request) structure is |
---|
59 | * used to read/write a number of blocks from/to device. |
---|
60 | */ |
---|
61 | typedef struct blkdev_request { |
---|
62 | blkdev_request_op req; /* Block device operation (read or write) */ |
---|
63 | blkdev_request_cb req_done; /* Callback function */ |
---|
64 | void *done_arg; /* Argument to be passed to callback function*/ |
---|
65 | rtems_status_code status; /* Last I/O operation completion status */ |
---|
66 | int error; /* If status != RTEMS_SUCCESSFUL, this field |
---|
67 | * contains error code |
---|
68 | */ |
---|
69 | blkdev_bnum start; /* Start block number */ |
---|
70 | rtems_unsigned32 count; /* Number of blocks to be exchanged */ |
---|
71 | rtems_unsigned32 bufnum; /* Number of buffers provided */ |
---|
72 | |
---|
73 | blkdev_sg_buffer bufs[0];/* List of scatter/gather buffers */ |
---|
74 | } blkdev_request; |
---|
75 | |
---|
76 | /* Block device IOCTL request codes */ |
---|
77 | #define BLKIO_REQUEST _IOWR('B', 1, blkdev_request) |
---|
78 | #define BLKIO_GETBLKSIZE _IO('B', 2) |
---|
79 | #define BLKIO_GETSIZE _IO('B', 3) |
---|
80 | #define BLKIO_SYNCDEV _IO('B', 4) |
---|
81 | |
---|
82 | /* Device driver interface conventions suppose that driver may |
---|
83 | * contain initialize/open/close/read/write/ioctl entry points. These |
---|
84 | * primitives (except initialize) can be implemented in generic fashion, |
---|
85 | * based upon supplied block device driver ioctl handler. Every block |
---|
86 | * device driver should provide initialize entry point, which is register |
---|
87 | * all block devices and appropriate ioctl handlers. |
---|
88 | */ |
---|
89 | |
---|
90 | #define GENERIC_BLOCK_DEVICE_DRIVER_ENTRIES \ |
---|
91 | rtems_blkdev_generic_open, rtems_blkdev_generic_close, \ |
---|
92 | rtems_blkdev_generic_read, rtems_blkdev_generic_write, \ |
---|
93 | rtems_blkdev_generic_ioctl |
---|
94 | |
---|
95 | /* blkdev_generic_read -- |
---|
96 | * Generic block device read primitive. Implemented using block device |
---|
97 | * buffer management primitives. |
---|
98 | */ |
---|
99 | rtems_device_driver |
---|
100 | rtems_blkdev_generic_read( |
---|
101 | rtems_device_major_number major, |
---|
102 | rtems_device_minor_number minor, |
---|
103 | void * arg |
---|
104 | ); |
---|
105 | |
---|
106 | /* blkdev_generic_write -- |
---|
107 | * Generic block device driver write primitive. Implemented using block |
---|
108 | * device buffer management primitives. |
---|
109 | */ |
---|
110 | rtems_device_driver |
---|
111 | rtems_blkdev_generic_write( |
---|
112 | rtems_device_major_number major, |
---|
113 | rtems_device_minor_number minor, |
---|
114 | void * arg |
---|
115 | ); |
---|
116 | |
---|
117 | /* blkdev_generic_open -- |
---|
118 | * Generic block device open primitive. |
---|
119 | */ |
---|
120 | rtems_device_driver |
---|
121 | rtems_blkdev_generic_open( |
---|
122 | rtems_device_major_number major, |
---|
123 | rtems_device_minor_number minor, |
---|
124 | void * arg |
---|
125 | ); |
---|
126 | |
---|
127 | /* blkdev_generic_close -- |
---|
128 | * Generic block device close primitive. |
---|
129 | */ |
---|
130 | rtems_device_driver |
---|
131 | rtems_blkdev_generic_close( |
---|
132 | rtems_device_major_number major, |
---|
133 | rtems_device_minor_number minor, |
---|
134 | void * arg |
---|
135 | ); |
---|
136 | |
---|
137 | /* blkdev_generic_ioctl -- |
---|
138 | * Generic block device ioctl primitive. |
---|
139 | */ |
---|
140 | rtems_device_driver |
---|
141 | rtems_blkdev_generic_ioctl( |
---|
142 | rtems_device_major_number major, |
---|
143 | rtems_device_minor_number minor, |
---|
144 | void * arg |
---|
145 | ); |
---|
146 | |
---|
147 | #ifdef __cplusplus |
---|
148 | } |
---|
149 | #endif |
---|
150 | |
---|
151 | #endif |
---|