[e51bd96] | 1 | /* |
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| 2 | * diskdevs.c - Physical and logical block devices (disks) support |
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| 3 | * |
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| 4 | * Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia |
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| 5 | * Author: Victor V. Vengerov <vvv@oktet.ru> |
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| 6 | * |
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| 7 | * @(#) $Id$ |
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| 8 | */ |
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| 9 | |
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| 10 | |
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| 11 | #include <rtems.h> |
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| 12 | #include <rtems/libio.h> |
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| 13 | #include <stdlib.h> |
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[f1c22e0] | 14 | #include <unistd.h> /* unlink */ |
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[e51bd96] | 15 | #include <string.h> |
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| 16 | |
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| 17 | #include "rtems/diskdevs.h" |
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| 18 | #include "rtems/bdbuf.h" |
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| 19 | |
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| 20 | #define DISKTAB_INITIAL_SIZE 32 |
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| 21 | |
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| 22 | /* Table of disk devices having the same major number */ |
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| 23 | struct disk_device_table { |
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| 24 | disk_device **minor; /* minor-indexed disk device table */ |
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| 25 | int size; /* Number of entries in the table */ |
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| 26 | }; |
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| 27 | |
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| 28 | /* Pointer to [major].minor[minor] indexed array of disk devices */ |
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| 29 | static struct disk_device_table *disktab; |
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| 30 | |
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| 31 | /* Number of allocated entries in disktab table */ |
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| 32 | static int disktab_size; |
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| 33 | |
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| 34 | /* Mutual exclusion semaphore for disk devices table */ |
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| 35 | static rtems_id diskdevs_mutex; |
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| 36 | |
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| 37 | /* Flag meaning that disk I/O, buffering etc. already has been initialized. */ |
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| 38 | static boolean disk_io_initialized = FALSE; |
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| 39 | |
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| 40 | /* diskdevs data structures protection flag. |
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| 41 | * Normally, only table lookup operations performed. It is quite fast, so |
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| 42 | * it is possible to done lookups when interrupts are disabled, avoiding |
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| 43 | * obtaining the semaphore. This flags sets immediately after entering in |
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| 44 | * mutex-protected section and cleared before leaving this section in |
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| 45 | * "big" primitives like add/delete new device etc. Lookup function first |
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| 46 | * disable interrupts and check this flag. If it is set, lookup function |
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| 47 | * will be blocked on semaphore and lookup operation will be performed in |
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| 48 | * semaphore-protected code. If it is not set (very-very frequent case), |
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| 49 | * we can do lookup safely, enable interrupts and return result. |
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| 50 | */ |
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| 51 | static volatile rtems_boolean diskdevs_protected; |
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| 52 | |
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| 53 | /* create_disk_entry -- |
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| 54 | * Return pointer to the disk_entry structure for the specified device, or |
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| 55 | * create one if it is not exists. |
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| 56 | * |
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| 57 | * PARAMETERS: |
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| 58 | * dev - device id (major, minor) |
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| 59 | * |
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| 60 | * RETURNS: |
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| 61 | * pointer to the disk device descirptor entry, or NULL if no memory |
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| 62 | * available for its creation. |
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| 63 | */ |
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| 64 | static disk_device * |
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| 65 | create_disk_entry(dev_t dev) |
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| 66 | { |
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| 67 | rtems_device_major_number major; |
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| 68 | rtems_device_minor_number minor; |
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| 69 | struct disk_device **d; |
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| 70 | |
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| 71 | rtems_filesystem_split_dev_t (dev, major, minor); |
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| 72 | |
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| 73 | if (major >= disktab_size) |
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| 74 | { |
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| 75 | struct disk_device_table *p; |
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| 76 | int newsize; |
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| 77 | int i; |
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| 78 | newsize = disktab_size * 2; |
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| 79 | if (major >= newsize) |
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| 80 | newsize = major + 1; |
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| 81 | p = realloc(disktab, sizeof(struct disk_device_table) * newsize); |
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| 82 | if (p == NULL) |
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| 83 | return NULL; |
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| 84 | p += disktab_size; |
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| 85 | for (i = disktab_size; i < newsize; i++, p++) |
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| 86 | { |
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| 87 | p->minor = NULL; |
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| 88 | p->size = 0; |
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| 89 | } |
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| 90 | disktab_size = newsize; |
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| 91 | } |
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| 92 | |
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| 93 | if ((disktab[major].minor == NULL) || |
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| 94 | (minor >= disktab[major].size)) |
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| 95 | { |
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| 96 | int newsize; |
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| 97 | disk_device **p; |
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| 98 | int i; |
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| 99 | int s = disktab[major].size; |
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| 100 | |
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| 101 | if (s == 0) |
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| 102 | newsize = DISKTAB_INITIAL_SIZE; |
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| 103 | else |
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| 104 | newsize = s * 2; |
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| 105 | if (minor >= newsize) |
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| 106 | newsize = minor + 1; |
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| 107 | |
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| 108 | p = realloc(disktab[major].minor, sizeof(disk_device *) * newsize); |
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| 109 | if (p == NULL) |
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| 110 | return NULL; |
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| 111 | disktab[major].minor = p; |
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| 112 | p += s; |
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| 113 | for (i = s; i < newsize; i++, p++) |
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| 114 | *p = NULL; |
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| 115 | disktab[major].size = newsize; |
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| 116 | } |
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| 117 | |
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| 118 | d = disktab[major].minor + minor; |
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| 119 | if (*d == NULL) |
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| 120 | { |
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| 121 | *d = calloc(1, sizeof(disk_device)); |
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| 122 | } |
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| 123 | return *d; |
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| 124 | } |
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| 125 | |
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| 126 | /* get_disk_entry -- |
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| 127 | * Get disk device descriptor by device number. |
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| 128 | * |
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| 129 | * PARAMETERS: |
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| 130 | * dev - block device number |
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| 131 | * |
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| 132 | * RETURNS: |
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| 133 | * Pointer to the disk device descriptor corresponding to the specified |
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| 134 | * device number, or NULL if disk device with such number not exists. |
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| 135 | */ |
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| 136 | static inline disk_device * |
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| 137 | get_disk_entry(dev_t dev) |
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| 138 | { |
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| 139 | rtems_device_major_number major; |
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| 140 | rtems_device_minor_number minor; |
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| 141 | struct disk_device_table *dtab; |
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| 142 | |
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| 143 | rtems_filesystem_split_dev_t (dev, major, minor); |
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| 144 | |
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| 145 | if ((major >= disktab_size) || (disktab == NULL)) |
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| 146 | return NULL; |
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| 147 | |
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| 148 | dtab = disktab + major; |
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| 149 | |
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| 150 | if ((minor >= dtab->size) || (dtab->minor == NULL)) |
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| 151 | return NULL; |
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| 152 | |
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| 153 | return dtab->minor[minor]; |
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| 154 | } |
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| 155 | |
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| 156 | /* create_disk -- |
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| 157 | * Check that disk entry for specified device number is not defined |
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| 158 | * and create it. |
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| 159 | * |
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| 160 | * PARAMETERS: |
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| 161 | * dev - device identifier (major, minor numbers) |
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| 162 | * name - character name of device (e.g. /dev/hda) |
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| 163 | * disdev - placeholder for pointer to created disk descriptor |
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| 164 | * |
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| 165 | * RETURNS: |
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| 166 | * RTEMS_SUCCESSFUL if disk entry successfully created, or |
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| 167 | * error code if error occured (device already registered, |
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| 168 | * no memory available). |
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| 169 | */ |
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| 170 | static rtems_status_code |
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| 171 | create_disk(dev_t dev, char *name, disk_device **diskdev) |
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| 172 | { |
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| 173 | disk_device *dd; |
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| 174 | char *n; |
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| 175 | |
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| 176 | dd = get_disk_entry(dev); |
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| 177 | if (dd != NULL) |
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| 178 | { |
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| 179 | return RTEMS_RESOURCE_IN_USE; |
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| 180 | } |
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| 181 | |
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| 182 | if (name == NULL) |
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| 183 | { |
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| 184 | n = NULL; |
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| 185 | } |
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| 186 | else |
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| 187 | { |
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| 188 | int nlen = strlen(name) + 1; |
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| 189 | n = malloc(nlen); |
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| 190 | if (n == NULL) |
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| 191 | return RTEMS_NO_MEMORY; |
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| 192 | strncpy(n, name, nlen); |
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| 193 | } |
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| 194 | |
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| 195 | dd = create_disk_entry(dev); |
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| 196 | if (dd == NULL) |
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| 197 | { |
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| 198 | free(n); |
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| 199 | return RTEMS_NO_MEMORY; |
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| 200 | } |
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| 201 | |
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| 202 | dd->dev = dev; |
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| 203 | dd->name = n; |
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| 204 | |
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| 205 | *diskdev = dd; |
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| 206 | |
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| 207 | return RTEMS_SUCCESSFUL; |
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| 208 | } |
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| 209 | |
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| 210 | /* rtems_disk_create_phys -- |
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| 211 | * Create physical disk entry. This function usually invoked from |
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| 212 | * block device driver initialization code when physical device |
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| 213 | * detected in the system. Device driver should provide ioctl handler |
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| 214 | * to allow block device access operations. This primitive will register |
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| 215 | * device in rtems (invoke rtems_io_register_name). |
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| 216 | * |
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| 217 | * PARAMETERS: |
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| 218 | * dev - device identifier (major, minor numbers) |
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| 219 | * block_size - size of disk block (minimum data transfer unit); must be |
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| 220 | * power of 2 |
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| 221 | * disk_size - number of blocks on device |
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| 222 | * handler - IOCTL handler (function providing basic block input/output |
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| 223 | * request handling BIOREQUEST and other device management |
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| 224 | * operations) |
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| 225 | * name - character name of device (e.g. /dev/hda) |
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| 226 | * |
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| 227 | * RETURNS: |
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| 228 | * RTEMS_SUCCESSFUL if information about new physical disk added, or |
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| 229 | * error code if error occured (device already registered, wrong block |
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| 230 | * size value, no memory available). |
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| 231 | */ |
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| 232 | rtems_status_code |
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| 233 | rtems_disk_create_phys(dev_t dev, int block_size, int disk_size, |
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| 234 | block_device_ioctl handler, |
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| 235 | char *name) |
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| 236 | { |
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| 237 | int bs_log2; |
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| 238 | int i; |
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| 239 | disk_device *dd; |
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| 240 | rtems_status_code rc; |
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| 241 | rtems_bdpool_id pool; |
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| 242 | rtems_device_major_number major; |
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| 243 | rtems_device_minor_number minor; |
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| 244 | |
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| 245 | rtems_filesystem_split_dev_t (dev, major, minor); |
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| 246 | |
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| 247 | |
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| 248 | for (bs_log2 = 0, i = block_size; (i & 1) == 0; i >>= 1, bs_log2++); |
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| 249 | if ((bs_log2 < 9) || (i != 1)) /* block size < 512 or not power of 2 */ |
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| 250 | return RTEMS_INVALID_NUMBER; |
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| 251 | |
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| 252 | rc = rtems_semaphore_obtain(diskdevs_mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT); |
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| 253 | if (rc != RTEMS_SUCCESSFUL) |
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| 254 | return rc; |
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| 255 | diskdevs_protected = TRUE; |
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| 256 | |
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| 257 | rc = rtems_bdbuf_find_pool(block_size, &pool); |
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| 258 | if (rc != RTEMS_SUCCESSFUL) |
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| 259 | { |
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| 260 | diskdevs_protected = FALSE; |
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| 261 | rtems_semaphore_release(diskdevs_mutex); |
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| 262 | return rc; |
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| 263 | } |
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| 264 | |
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| 265 | rc = create_disk(dev, name, &dd); |
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| 266 | if (rc != RTEMS_SUCCESSFUL) |
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| 267 | { |
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| 268 | diskdevs_protected = FALSE; |
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| 269 | rtems_semaphore_release(diskdevs_mutex); |
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| 270 | return rc; |
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| 271 | } |
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| 272 | |
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| 273 | dd->phys_dev = dd; |
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| 274 | dd->uses = 0; |
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| 275 | dd->start = 0; |
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| 276 | dd->size = disk_size; |
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| 277 | dd->block_size = block_size; |
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| 278 | dd->block_size_log2 = bs_log2; |
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| 279 | dd->ioctl = handler; |
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| 280 | dd->pool = pool; |
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| 281 | |
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| 282 | rc = rtems_io_register_name(name, major, minor); |
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| 283 | |
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| 284 | diskdevs_protected = FALSE; |
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| 285 | rtems_semaphore_release(diskdevs_mutex); |
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| 286 | |
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| 287 | return rc; |
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| 288 | } |
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| 289 | |
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| 290 | /* rtems_disk_create_log -- |
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| 291 | * Create logical disk entry. Logical disk is contiguous area on physical |
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| 292 | * disk. Disk may be splitted to several logical disks in several ways: |
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| 293 | * manually or using information stored in blocks on physical disk |
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| 294 | * (DOS-like partition table, BSD disk label, etc). This function usually |
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| 295 | * invoked from application when application-specific splitting are in use, |
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| 296 | * or from generic code which handle different logical disk organizations. |
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| 297 | * This primitive will register device in rtems (invoke |
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| 298 | * rtems_io_register_name). |
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| 299 | * |
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| 300 | * PARAMETERS: |
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| 301 | * dev - logical device identifier (major, minor numbers) |
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| 302 | * phys - physical device (block device which holds this logical disk) |
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| 303 | * identifier |
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| 304 | * start - starting block number on the physical device |
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| 305 | * size - logical disk size in blocks |
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| 306 | * name - logical disk name |
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| 307 | * |
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| 308 | * RETURNS: |
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| 309 | * RTEMS_SUCCESSFUL if logical device successfully added, or error code |
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| 310 | * if error occured (device already registered, no physical device |
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| 311 | * exists, logical disk is out of physical disk boundaries, no memory |
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| 312 | * available). |
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| 313 | */ |
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| 314 | rtems_status_code |
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| 315 | rtems_disk_create_log(dev_t dev, dev_t phys, int start, int size, char *name) |
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| 316 | { |
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| 317 | disk_device *dd; |
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| 318 | disk_device *pdd; |
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| 319 | rtems_status_code rc; |
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| 320 | rtems_device_major_number major; |
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| 321 | rtems_device_minor_number minor; |
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| 322 | |
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| 323 | rtems_filesystem_split_dev_t (dev, major, minor); |
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| 324 | |
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| 325 | rc = rtems_semaphore_obtain(diskdevs_mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT); |
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| 326 | if (rc != RTEMS_SUCCESSFUL) |
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| 327 | return rc; |
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| 328 | diskdevs_protected = TRUE; |
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| 329 | |
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| 330 | pdd = get_disk_entry(phys); |
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| 331 | if (pdd == NULL) |
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| 332 | { |
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| 333 | diskdevs_protected = FALSE; |
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| 334 | rtems_semaphore_release(diskdevs_mutex); |
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| 335 | return RTEMS_INVALID_NUMBER; |
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| 336 | } |
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| 337 | |
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| 338 | rc = create_disk(dev, name, &dd); |
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| 339 | if (rc != RTEMS_SUCCESSFUL) |
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| 340 | { |
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| 341 | diskdevs_protected = FALSE; |
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| 342 | rtems_semaphore_release(diskdevs_mutex); |
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| 343 | return rc; |
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| 344 | } |
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| 345 | |
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| 346 | dd->phys_dev = pdd; |
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| 347 | dd->uses = 0; |
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| 348 | dd->start = start; |
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| 349 | dd->size = size; |
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| 350 | dd->block_size = pdd->block_size; |
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| 351 | dd->block_size_log2 = pdd->block_size_log2; |
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| 352 | dd->ioctl = pdd->ioctl; |
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| 353 | |
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| 354 | rc = rtems_io_register_name(name, major, minor); |
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| 355 | |
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| 356 | diskdevs_protected = FALSE; |
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| 357 | rc = rtems_semaphore_release(diskdevs_mutex); |
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| 358 | |
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| 359 | return rc; |
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| 360 | } |
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| 361 | |
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| 362 | /* rtems_disk_delete -- |
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| 363 | * Delete physical or logical disk device. Device may be deleted if its |
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| 364 | * use counter (and use counters of all logical devices - if it is |
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| 365 | * physical device) equal to 0. When physical device deleted, |
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| 366 | * all logical devices deleted inherently. Appropriate devices removed |
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| 367 | * from "/dev" filesystem. |
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| 368 | * |
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| 369 | * PARAMETERS: |
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| 370 | * dev - device identifier (major, minor numbers) |
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| 371 | * |
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| 372 | * RETURNS: |
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| 373 | * RTEMS_SUCCESSFUL if block device successfully deleted, or error code |
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| 374 | * if error occured (device is not defined, device is in use). |
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| 375 | */ |
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| 376 | rtems_status_code |
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| 377 | rtems_disk_delete(dev_t dev) |
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| 378 | { |
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| 379 | rtems_status_code rc; |
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| 380 | int used; |
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| 381 | rtems_device_major_number maj; |
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| 382 | rtems_device_minor_number min; |
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| 383 | |
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| 384 | rc = rtems_semaphore_obtain(diskdevs_mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT); |
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| 385 | if (rc != RTEMS_SUCCESSFUL) |
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| 386 | return rc; |
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| 387 | diskdevs_protected = TRUE; |
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| 388 | |
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| 389 | /* Check if this device is in use -- calculate usage counter */ |
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| 390 | used = 0; |
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| 391 | for (maj = 0; maj < disktab_size; maj++) |
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| 392 | { |
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| 393 | struct disk_device_table *dtab = disktab + maj; |
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| 394 | if (dtab != NULL) |
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| 395 | { |
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| 396 | for (min = 0; min < dtab->size; min++) |
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| 397 | { |
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| 398 | disk_device *dd = dtab->minor[min]; |
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| 399 | if ((dd != NULL) && (dd->phys_dev->dev == dev)) |
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| 400 | used += dd->uses; |
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| 401 | } |
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| 402 | } |
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| 403 | } |
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| 404 | |
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| 405 | if (used != 0) |
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| 406 | { |
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| 407 | diskdevs_protected = FALSE; |
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| 408 | rtems_semaphore_release(diskdevs_mutex); |
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| 409 | return RTEMS_RESOURCE_IN_USE; |
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| 410 | } |
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| 411 | |
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| 412 | /* Delete this device and all of its logical devices */ |
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| 413 | for (maj = 0; maj < disktab_size; maj++) |
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| 414 | { |
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| 415 | struct disk_device_table *dtab = disktab +maj; |
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| 416 | if (dtab != NULL) |
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| 417 | { |
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| 418 | for (min = 0; min < dtab->size; min++) |
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| 419 | { |
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| 420 | disk_device *dd = dtab->minor[min]; |
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| 421 | if ((dd != NULL) && (dd->phys_dev->dev == dev)) |
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| 422 | { |
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| 423 | unlink(dd->name); |
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| 424 | free(dd->name); |
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| 425 | free(dd); |
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| 426 | dtab->minor[min] = NULL; |
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| 427 | } |
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| 428 | } |
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| 429 | } |
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| 430 | } |
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| 431 | |
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| 432 | diskdevs_protected = FALSE; |
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| 433 | rc = rtems_semaphore_release(diskdevs_mutex); |
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| 434 | return rc; |
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| 435 | } |
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| 436 | |
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| 437 | /* rtems_disk_lookup -- |
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| 438 | * Find block device descriptor by its device identifier. |
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| 439 | * |
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| 440 | * PARAMETERS: |
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| 441 | * dev - device identifier (major, minor numbers) |
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| 442 | * |
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| 443 | * RETURNS: |
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| 444 | * pointer to the block device descriptor, or NULL if no such device |
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| 445 | * exists. |
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| 446 | */ |
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| 447 | disk_device * |
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| 448 | rtems_disk_lookup(dev_t dev) |
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| 449 | { |
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| 450 | rtems_interrupt_level level; |
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| 451 | disk_device *dd; |
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| 452 | rtems_status_code rc; |
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| 453 | |
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| 454 | rtems_interrupt_disable(level); |
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| 455 | if (diskdevs_protected) |
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| 456 | { |
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| 457 | rtems_interrupt_enable(level); |
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| 458 | rc = rtems_semaphore_obtain(diskdevs_mutex, RTEMS_WAIT, |
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| 459 | RTEMS_NO_TIMEOUT); |
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| 460 | if (rc != RTEMS_SUCCESSFUL) |
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| 461 | return NULL; |
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| 462 | diskdevs_protected = TRUE; |
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| 463 | dd = get_disk_entry(dev); |
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| 464 | dd->uses++; |
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| 465 | diskdevs_protected = FALSE; |
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| 466 | rtems_semaphore_release(diskdevs_mutex); |
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| 467 | return dd; |
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| 468 | } |
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| 469 | else |
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| 470 | { |
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| 471 | /* Frequent and quickest case */ |
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| 472 | dd = get_disk_entry(dev); |
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| 473 | dd->uses++; |
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| 474 | rtems_interrupt_enable(level); |
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| 475 | return dd; |
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| 476 | } |
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| 477 | } |
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| 478 | |
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| 479 | /* rtems_disk_release -- |
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| 480 | * Release disk_device structure (decrement usage counter to 1). |
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| 481 | * |
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| 482 | * PARAMETERS: |
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| 483 | * dd - pointer to disk device structure |
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| 484 | * |
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| 485 | * RETURNS: |
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| 486 | * RTEMS_SUCCESSFUL |
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| 487 | */ |
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| 488 | rtems_status_code |
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| 489 | rtems_disk_release(disk_device *dd) |
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| 490 | { |
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| 491 | rtems_interrupt_level level; |
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| 492 | rtems_interrupt_disable(level); |
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| 493 | dd->uses--; |
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| 494 | rtems_interrupt_enable(level); |
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| 495 | return RTEMS_SUCCESSFUL; |
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| 496 | } |
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| 497 | |
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| 498 | /* rtems_disk_next -- |
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| 499 | * Disk device enumerator. Looking for device having device number larger |
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| 500 | * than dev and return disk device descriptor for it. If there are no |
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| 501 | * such device, NULL value returned. |
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| 502 | * |
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| 503 | * PARAMETERS: |
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| 504 | * dev - device number (use -1 to start search) |
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| 505 | * |
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| 506 | * RETURNS: |
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| 507 | * Pointer to the disk descriptor for next disk device, or NULL if all |
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| 508 | * devices enumerated. |
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| 509 | */ |
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| 510 | disk_device * |
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| 511 | rtems_disk_next(dev_t dev) |
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| 512 | { |
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| 513 | rtems_device_major_number major; |
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| 514 | rtems_device_minor_number minor; |
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| 515 | struct disk_device_table *dtab; |
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| 516 | |
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| 517 | dev++; |
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| 518 | rtems_filesystem_split_dev_t (dev, major, minor); |
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| 519 | |
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| 520 | if (major >= disktab_size) |
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| 521 | return NULL; |
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| 522 | |
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| 523 | dtab = disktab + major; |
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| 524 | while (TRUE) |
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| 525 | { |
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| 526 | if ((dtab == NULL) || (minor > dtab->size)) |
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| 527 | { |
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| 528 | major++; minor = 0; |
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| 529 | if (major >= disktab_size) |
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| 530 | return NULL; |
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| 531 | dtab = disktab + major; |
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| 532 | } |
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| 533 | else if (dtab->minor[minor] == NULL) |
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| 534 | { |
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| 535 | minor++; |
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| 536 | } |
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| 537 | else |
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| 538 | return dtab->minor[minor]; |
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| 539 | } |
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| 540 | } |
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| 541 | |
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| 542 | /* rtems_disk_initialize -- |
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| 543 | * Initialization of disk device library (initialize all data structures, |
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| 544 | * etc.) |
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| 545 | * |
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| 546 | * PARAMETERS: |
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| 547 | * none |
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| 548 | * |
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| 549 | * RETURNS: |
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| 550 | * RTEMS_SUCCESSFUL if library initialized, or error code if error |
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| 551 | * occured. |
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| 552 | */ |
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| 553 | rtems_status_code |
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| 554 | rtems_disk_io_initialize(void) |
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| 555 | { |
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| 556 | rtems_status_code rc; |
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| 557 | |
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| 558 | if (disk_io_initialized) |
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| 559 | return RTEMS_SUCCESSFUL; |
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| 560 | |
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| 561 | disktab_size = DISKTAB_INITIAL_SIZE; |
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| 562 | disktab = calloc(disktab_size, sizeof(struct disk_device_table)); |
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| 563 | if (disktab == NULL) |
---|
| 564 | return RTEMS_NO_MEMORY; |
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| 565 | |
---|
| 566 | diskdevs_protected = FALSE; |
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| 567 | rc = rtems_semaphore_create( |
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| 568 | rtems_build_name('D', 'D', 'E', 'V'), 1, |
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| 569 | RTEMS_FIFO | RTEMS_BINARY_SEMAPHORE | RTEMS_NO_INHERIT_PRIORITY | |
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| 570 | RTEMS_NO_PRIORITY_CEILING | RTEMS_LOCAL, 0, &diskdevs_mutex); |
---|
| 571 | |
---|
| 572 | if (rc != RTEMS_SUCCESSFUL) |
---|
| 573 | { |
---|
| 574 | free(disktab); |
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| 575 | return rc; |
---|
| 576 | } |
---|
| 577 | |
---|
| 578 | rc = rtems_bdbuf_init(rtems_bdbuf_configuration, |
---|
| 579 | rtems_bdbuf_configuration_size); |
---|
| 580 | |
---|
| 581 | if (rc != RTEMS_SUCCESSFUL) |
---|
| 582 | { |
---|
| 583 | rtems_semaphore_delete(diskdevs_mutex); |
---|
| 584 | free(disktab); |
---|
| 585 | return rc; |
---|
| 586 | } |
---|
| 587 | |
---|
| 588 | disk_io_initialized = 1; |
---|
| 589 | return RTEMS_SUCCESSFUL; |
---|
| 590 | } |
---|
| 591 | |
---|
| 592 | /* rtems_disk_io_done -- |
---|
| 593 | * Release all resources allocated for disk device interface. |
---|
| 594 | * |
---|
| 595 | * PARAMETERS: |
---|
| 596 | * none |
---|
| 597 | * |
---|
| 598 | * RETURNS: |
---|
| 599 | * RTEMS_SUCCESSFUL if all resources released, or error code if error |
---|
| 600 | * occured. |
---|
| 601 | */ |
---|
| 602 | rtems_status_code |
---|
| 603 | rtems_disk_io_done(void) |
---|
| 604 | { |
---|
| 605 | rtems_device_major_number maj; |
---|
| 606 | rtems_device_minor_number min; |
---|
| 607 | rtems_status_code rc; |
---|
| 608 | |
---|
| 609 | /* Free data structures */ |
---|
| 610 | for (maj = 0; maj < disktab_size; maj++) |
---|
| 611 | { |
---|
| 612 | struct disk_device_table *dtab = disktab + maj; |
---|
| 613 | if (dtab != NULL) |
---|
| 614 | { |
---|
| 615 | for (min = 0; min < dtab->size; min++) |
---|
| 616 | { |
---|
| 617 | disk_device *dd = dtab->minor[min]; |
---|
| 618 | unlink(dd->name); |
---|
| 619 | free(dd->name); |
---|
| 620 | free(dd); |
---|
| 621 | } |
---|
| 622 | free(dtab); |
---|
| 623 | } |
---|
| 624 | } |
---|
| 625 | free(disktab); |
---|
| 626 | |
---|
| 627 | rc = rtems_semaphore_release(diskdevs_mutex); |
---|
| 628 | |
---|
| 629 | /* XXX bdbuf should be released too! */ |
---|
| 630 | disk_io_initialized = 0; |
---|
| 631 | return rc; |
---|
| 632 | } |
---|