1 | /** |
---|
2 | * @file rtems/diskdevs.h |
---|
3 | * Physical and logical block devices (disks) support |
---|
4 | */ |
---|
5 | |
---|
6 | /* |
---|
7 | * Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia |
---|
8 | * Author: Victor V. Vengerov <vvv@oktet.ru> |
---|
9 | * |
---|
10 | * @(#) $Id$ |
---|
11 | */ |
---|
12 | |
---|
13 | #ifndef _RTEMS_DISKDEVS_H |
---|
14 | #define _RTEMS_DISKDEVS_H |
---|
15 | |
---|
16 | #ifdef __cplusplus |
---|
17 | extern "C" { |
---|
18 | #endif |
---|
19 | |
---|
20 | #include <rtems.h> |
---|
21 | #include <rtems/libio.h> |
---|
22 | #include <stdlib.h> |
---|
23 | |
---|
24 | /* Buffer pool identifier */ |
---|
25 | typedef int rtems_bdpool_id; |
---|
26 | |
---|
27 | #include "rtems/blkdev.h" |
---|
28 | |
---|
29 | /* Driver capabilities. */ |
---|
30 | |
---|
31 | /* Block device ioctl handler */ |
---|
32 | typedef int (* rtems_block_device_ioctl) (dev_t dev, uint32_t req, void *argp); |
---|
33 | |
---|
34 | /* rtems_disk_device: Entry of this type created for every disk device |
---|
35 | * (both for logical and physical disks). |
---|
36 | * Array of arrays of pointers to disk_device structures maintained. First |
---|
37 | * table indexed by major number and second table indexed by minor number. |
---|
38 | * Such data organization allow quick lookup using data structure of |
---|
39 | * moderated size. |
---|
40 | */ |
---|
41 | typedef struct rtems_disk_device { |
---|
42 | dev_t dev; /* Device ID (major + minor) */ |
---|
43 | struct rtems_disk_device *phys_dev; /* Physical device ID (the same |
---|
44 | as dev if this entry specifies |
---|
45 | the physical device) */ |
---|
46 | uint32_t capabilities; /* Driver capabilities. */ |
---|
47 | char *name; /* Disk device name */ |
---|
48 | int uses; /* Use counter. Device couldn't be |
---|
49 | removed if it is in use. */ |
---|
50 | uint32_t start; /* Starting block number (0 for |
---|
51 | physical devices, block offset |
---|
52 | on the related physical device |
---|
53 | for logical device) */ |
---|
54 | uint32_t size; /* Size of physical or logical disk |
---|
55 | in disk blocks */ |
---|
56 | uint32_t block_size; /* Size of device block (minimum |
---|
57 | transfer unit) in bytes |
---|
58 | (must be power of 2) */ |
---|
59 | uint32_t block_size_log2; /* log2 of block_size */ |
---|
60 | rtems_bdpool_id pool; /* Buffer pool assigned to this |
---|
61 | device */ |
---|
62 | rtems_block_device_ioctl ioctl; /* ioctl handler for this block |
---|
63 | device */ |
---|
64 | } rtems_disk_device; |
---|
65 | |
---|
66 | /* rtems_disk_create_phys -- |
---|
67 | * Create physical disk entry. This function usually invoked from |
---|
68 | * block device driver initialization code when physical device |
---|
69 | * detected in the system. Device driver should provide ioctl handler |
---|
70 | * to allow block device access operations. This primitive will register |
---|
71 | * device in rtems (invoke rtems_io_register_name). |
---|
72 | * |
---|
73 | * PARAMETERS: |
---|
74 | * dev - device identifier (major, minor numbers) |
---|
75 | * block_size - size of disk block (minimum data transfer unit); must be |
---|
76 | * power of 2 |
---|
77 | * disk_size - number of blocks on device |
---|
78 | * handler - IOCTL handler (function providing basic block input/output |
---|
79 | * request handling BIOREQUEST and other device management |
---|
80 | * operations) |
---|
81 | * name - character name of device (e.g. /dev/hda) |
---|
82 | * |
---|
83 | * RETURNS: |
---|
84 | * RTEMS_SUCCESSFUL if information about new physical disk added, or |
---|
85 | * error code if error occured (device already registered, wrong block |
---|
86 | * size value, no memory available). |
---|
87 | */ |
---|
88 | rtems_status_code |
---|
89 | rtems_disk_create_phys(dev_t dev, int block_size, int disk_size, |
---|
90 | rtems_block_device_ioctl handler, |
---|
91 | const char *name); |
---|
92 | |
---|
93 | /* rtems_disk_create_log -- |
---|
94 | * Create logical disk entry. Logical disk is contiguous area on physical |
---|
95 | * disk. Disk may be splitted to several logical disks in several ways: |
---|
96 | * manually or using information stored in blocks on physical disk |
---|
97 | * (DOS-like partition table, BSD disk label, etc). This function usually |
---|
98 | * invoked from application when application-specific splitting are in use, |
---|
99 | * or from generic code which handle different logical disk organizations. |
---|
100 | * This primitive will register device in rtems (invoke |
---|
101 | * rtems_io_register_name). |
---|
102 | * |
---|
103 | * PARAMETERS: |
---|
104 | * dev - logical device identifier (major, minor numbers) |
---|
105 | * phys - physical device (block device which holds this logical disk) |
---|
106 | * identifier |
---|
107 | * start - starting block number on the physical device |
---|
108 | * size - logical disk size in blocks |
---|
109 | * name - logical disk name |
---|
110 | * |
---|
111 | * RETURNS: |
---|
112 | * RTEMS_SUCCESSFUL if logical device successfully added, or error code |
---|
113 | * if error occured (device already registered, no physical device |
---|
114 | * exists, logical disk is out of physical disk boundaries, no memory |
---|
115 | * available). |
---|
116 | */ |
---|
117 | rtems_status_code |
---|
118 | rtems_disk_create_log(dev_t dev, dev_t phys, int start, int size, char *name); |
---|
119 | |
---|
120 | /* rtems_disk_delete -- |
---|
121 | * Delete physical or logical disk device. Device may be deleted if its |
---|
122 | * use counter (and use counters of all logical devices - if it is |
---|
123 | * physical device) equal to 0. When physical device deleted, |
---|
124 | * all logical devices deleted inherently. Appropriate devices removed |
---|
125 | * from "/dev" filesystem. |
---|
126 | * |
---|
127 | * PARAMETERS: |
---|
128 | * dev - device identifier (major, minor numbers) |
---|
129 | * |
---|
130 | * RETURNS: |
---|
131 | * RTEMS_SUCCESSFUL if block device successfully deleted, or error code |
---|
132 | * if error occured (device is not defined, device is in use). |
---|
133 | */ |
---|
134 | rtems_status_code |
---|
135 | rtems_disk_delete(dev_t dev); |
---|
136 | |
---|
137 | /* rtems_disk_obtain -- |
---|
138 | * Find block device descriptor by its device identifier. This function |
---|
139 | * increment usage counter to 1. User should release disk_device structure |
---|
140 | * by invoking rtems_disk_release primitive. |
---|
141 | * |
---|
142 | * PARAMETERS: |
---|
143 | * dev - device identifier (major, minor numbers) |
---|
144 | * |
---|
145 | * RETURNS: |
---|
146 | * pointer to the block device descriptor, or NULL if no such device |
---|
147 | * exists. |
---|
148 | */ |
---|
149 | rtems_disk_device * |
---|
150 | rtems_disk_obtain(dev_t dev); |
---|
151 | |
---|
152 | /* rtems_disk_release -- |
---|
153 | * Release disk_device structure (decrement usage counter to 1). |
---|
154 | * |
---|
155 | * PARAMETERS: |
---|
156 | * dd - pointer to disk device structure |
---|
157 | * |
---|
158 | * RETURNS: |
---|
159 | * RTEMS_SUCCESSFUL |
---|
160 | * |
---|
161 | * NOTE: |
---|
162 | * It should be implemented as inline function. |
---|
163 | */ |
---|
164 | rtems_status_code |
---|
165 | rtems_disk_release(rtems_disk_device *dd); |
---|
166 | |
---|
167 | /* rtems_disk_next -- |
---|
168 | * Disk device enumerator. Looking for device having device number larger |
---|
169 | * than dev and return disk device descriptor for it. If there are no |
---|
170 | * such device, NULL value returned. |
---|
171 | * |
---|
172 | * PARAMETERS: |
---|
173 | * dev - device number (use -1 to start search) |
---|
174 | * |
---|
175 | * RETURNS: |
---|
176 | * Pointer to the disk descriptor for next disk device, or NULL if all |
---|
177 | * devices enumerated. */ |
---|
178 | rtems_disk_device * |
---|
179 | rtems_disk_next(dev_t dev); |
---|
180 | |
---|
181 | /* rtems_diskio_initialize -- |
---|
182 | * Initialization of disk device library (initialize all data structures, |
---|
183 | * etc.) |
---|
184 | * |
---|
185 | * PARAMETERS: |
---|
186 | * none |
---|
187 | * |
---|
188 | * RETURNS: |
---|
189 | * RTEMS_SUCCESSFUL if library initialized, or error code if error |
---|
190 | * occured. |
---|
191 | */ |
---|
192 | rtems_status_code |
---|
193 | rtems_disk_io_initialize(void); |
---|
194 | |
---|
195 | /* rtems_diskio_done -- |
---|
196 | * Release all resources allocated for disk device interface. |
---|
197 | * |
---|
198 | * PARAMETERS: |
---|
199 | * none |
---|
200 | * |
---|
201 | * RETURNS: |
---|
202 | * RTEMS_SUCCESSFUL if all resources released, or error code if error |
---|
203 | * occured. |
---|
204 | */ |
---|
205 | rtems_status_code |
---|
206 | rtems_disk_io_done(void); |
---|
207 | |
---|
208 | #ifdef __cplusplus |
---|
209 | } |
---|
210 | #endif |
---|
211 | |
---|
212 | #endif |
---|