drivers/block/z2ram.c

   1 /*
   2 ** z2ram - Amiga pseudo-driver to access 16bit-RAM in ZorroII space
   3 **         as a block device, to be used as a RAM disk or swap space
   4 **
   5 ** Copyright (C) 1994 by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)
   6 **
   7 ** ++Geert: support for zorro_unused_z2ram, better range checking
   8 ** ++roman: translate accesses via an array
   9 ** ++Milan: support for ChipRAM usage
  10 ** ++yambo: converted to 2.0 kernel
  11 ** ++yambo: modularized and support added for 3 minor devices including:
  12 **          MAJOR  MINOR  DESCRIPTION
  13 **          -----  -----  ----------------------------------------------
  14 **          37     0       Use Zorro II and Chip ram
  15 **          37     1       Use only Zorro II ram
  16 **          37     2       Use only Chip ram
  17 **
  18 ** Permission to use, copy, modify, and distribute this software and its
  19 ** documentation for any purpose and without fee is hereby granted, provided
  20 ** that the above copyright notice appear in all copies and that both that
  21 ** copyright notice and this permission notice appear in supporting
  22 ** documentation.  This software is provided "as is" without express or
  23 ** implied warranty.
  24 */
  25
  26 #define MAJOR_NR    Z2RAM_MAJOR
  27
  28 #include <linux/major.h>
  29 #include <linux/malloc.h>
  30 #include <linux/blk.h>
  31 #include <linux/init.h>
  32
  33 #if defined(MODULE)
  34 #include <linux/module.h>
  35 #endif
  36
  37 #include <asm/setup.h>
  38 #include <asm/bitops.h>
  39 #include <asm/amigahw.h>
  40 #include <linux/zorro.h>
  41
  42 #define TRUE                  (1)
  43 #define FALSE                 (0)
  44
  45 #define Z2MINOR_COMBINED      (0)
  46 #define Z2MINOR_Z2ONLY        (1)
  47 #define Z2MINOR_CHIPONLY      (2)
  48
  49 #define Z2RAM_CHUNK1024       ( Z2RAM_CHUNKSIZE >> 10 )
  50
  51 static u_long *z2ram_map    = NULL;
  52 static u_long z2ram_size    = 0;
  53 static int z2_blocksizes[3] = { 1024, 1024, 1024 };
  54 static int z2_sizes[3]      = {    0,    0,    0 };
  55 static int z2_count         = 0;
  56 static int chip_count       = 0;
  57 static int current_device   = -1;
  58
  59 static void
  60 do_z2_request( void )
  61 {
  62     u_long start, len, addr, size;
  63
  64     while ( TRUE )
  65     {
  66         INIT_REQUEST;
  67
  68         start = CURRENT->sector << 9;
  69         len  = CURRENT->current_nr_sectors << 9;
  70
  71         if ( ( start + len ) > z2ram_size )
  72         {
  73             printk( KERN_ERR DEVICE_NAME ": bad access: block=%ld, count=%ld\n",
  74                 CURRENT->sector,
  75                 CURRENT->current_nr_sectors);
  76             end_request( FALSE );
  77             continue;
  78         }
  79
  80         if ( ( CURRENT->cmd != READ ) && ( CURRENT->cmd != WRITE ) )
  81         {
  82             printk( KERN_ERR DEVICE_NAME ": bad command: %d\n", CURRENT->cmd );
  83             end_request( FALSE );
  84             continue;
  85         }
  86
  87         while ( len )
  88         {
  89             addr = start & Z2RAM_CHUNKMASK;
  90             size = Z2RAM_CHUNKSIZE - addr;
  91             if ( len < size )
  92                 size = len;
  93
  94             addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
  95
  96             if ( CURRENT->cmd == READ )
  97                 memcpy( CURRENT->buffer, (char *)addr, size );
  98             else
  99                 memcpy( (char *)addr, CURRENT->buffer, size );
 100
 101             start += size;
 102             len -= size;
 103         }
 104
 105         end_request( TRUE );
 106     }
 107 }
 108
 109 static void
 110 get_z2ram( void )
 111 {
 112     int i;
 113
 114     for ( i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++ )
 115     {
 116         if ( test_bit( i, zorro_unused_z2ram ) )
 117         {
 118             z2_count++;
 119             z2ram_map[ z2ram_size++ ] =
 120                 ZTWO_VADDR( Z2RAM_START ) + ( i << Z2RAM_CHUNKSHIFT );
 121             clear_bit( i, zorro_unused_z2ram );
 122         }
 123     }
 124
 125     return;
 126 }
 127
 128 static void
 129 get_chipram( void )
 130 {
 131
 132     while ( amiga_chip_avail() > ( Z2RAM_CHUNKSIZE * 4 ) )
 133     {
 134         chip_count++;
 135         z2ram_map[ z2ram_size ] =
 136             (u_long)amiga_chip_alloc( Z2RAM_CHUNKSIZE );
 137
 138         if ( z2ram_map[ z2ram_size ] == 0 )
 139         {
 140             break;
 141         }
 142
 143         z2ram_size++;
 144     }
 145
 146     return;
 147 }
 148
 149 static int
 150 z2_open( struct inode *inode, struct file *filp )
 151 {
 152     int device;
 153     int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
 154         sizeof( z2ram_map[0] );
 155     int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
 156         sizeof( z2ram_map[0] );
 157
 158     device = DEVICE_NR( inode->i_rdev );
 159
 160     if ( current_device != -1 && current_device != device )
 161     {
 162         return -EBUSY;
 163     }
 164
 165     if ( current_device == -1 )
 166     {
 167         z2_count   = 0;
 168         chip_count = 0;
 169         z2ram_size = 0;
 170
 171         switch ( device )
 172         {
 173             case Z2MINOR_COMBINED:
 174
 175                 z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
 176                 if ( z2ram_map == NULL )
 177                 {
 178                     printk( KERN_ERR DEVICE_NAME
 179                         ": cannot get mem for z2ram_map\n" );
 180                     return -ENOMEM;
 181                 }
 182
 183                 get_z2ram();
 184                 get_chipram();
 185
 186                 if ( z2ram_size != 0 )
 187                     printk( KERN_INFO DEVICE_NAME
 188                         ": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
 189                         z2_count * Z2RAM_CHUNK1024,
 190                         chip_count * Z2RAM_CHUNK1024,
 191                         ( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
 192
 193             break;
 194
 195             case Z2MINOR_Z2ONLY:
 196                 z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
 197                 if ( z2ram_map == NULL )
 198                 {
 199                     printk( KERN_ERR DEVICE_NAME
 200                         ": cannot get mem for z2ram_map\n" );
 201                     return -ENOMEM;
 202                 }
 203
 204                 get_z2ram();
 205
 206                 if ( z2ram_size != 0 )
 207                     printk( KERN_INFO DEVICE_NAME
 208                         ": using %iK of Zorro II RAM\n",
 209                         z2_count * Z2RAM_CHUNK1024 );
 210
 211             break;
 212
 213             case Z2MINOR_CHIPONLY:
 214                 z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
 215                 if ( z2ram_map == NULL )
 216                 {
 217                     printk( KERN_ERR DEVICE_NAME
 218                         ": cannot get mem for z2ram_map\n" );
 219                     return -ENOMEM;
 220                 }
 221
 222                 get_chipram();
 223
 224                 if ( z2ram_size != 0 )
 225                     printk( KERN_INFO DEVICE_NAME
 226                         ": using %iK Chip RAM\n",
 227                         chip_count * Z2RAM_CHUNK1024 );
 228
 229             break;
 230
 231             default:
 232                 return -ENODEV;
 233         }
 234
 235         if ( z2ram_size == 0 )
 236         {
 237             kfree( z2ram_map );
 238             printk( KERN_NOTICE DEVICE_NAME
 239                 ": no unused ZII/Chip RAM found\n" );
 240             return -ENOMEM;
 241         }
 242
 243         current_device = device;
 244         z2ram_size <<= Z2RAM_CHUNKSHIFT;
 245         z2_sizes[ device ] = z2ram_size >> 10;
 246         blk_size[ MAJOR_NR ] = z2_sizes;
 247     }
 248
 249 #if defined(MODULE)
 250     MOD_INC_USE_COUNT;
 251 #endif
 252
 253     return 0;
 254 }
 255
 256 static void
 257 z2_release( struct inode *inode, struct file *filp )
 258 {
 259
 260     if ( current_device == -1 )
 261         return;
 262
 263     sync_dev( inode->i_rdev );
 264
 265 #if defined(MODULE)
 266     MOD_DEC_USE_COUNT;
 267 #endif
 268
 269     return;
 270 }
 271
 272 static struct file_operations z2_fops =
 273 {
 274         NULL,                   /* lseek - default */
 275         block_read,             /* read - general block-dev read */
 276         block_write,            /* write - general block-dev write */
 277         NULL,                   /* readdir - bad */
 278         NULL,                   /* poll */
 279         NULL,                   /* ioctl */
 280         NULL,                   /* mmap */
 281         z2_open,                /* open */
 282         NULL,                   /* flush */
 283         z2_release,             /* release */
 284         block_fsync             /* fsync */
 285 };
 286
 287 __initfunc(int
 288 z2_init( void ))
 289 {
 290
 291     if ( !MACH_IS_AMIGA )
 292         return -ENXIO;
 293
 294     if ( register_blkdev( MAJOR_NR, DEVICE_NAME, &z2_fops ) )
 295     {
 296         printk( KERN_ERR DEVICE_NAME ": Unable to get major %d\n",
 297             MAJOR_NR );
 298         return -EBUSY;
 299     }
 300
 301     blk_dev[ MAJOR_NR ].request_fn = DEVICE_REQUEST;
 302     blksize_size[ MAJOR_NR ] = z2_blocksizes;
 303     blk_size[ MAJOR_NR ] = z2_sizes;
 304
 305     return 0;
 306 }
 307
 308 #if defined(MODULE)
 309 int
 310 init_module( void )
 311 {
 312     int error;
 313
 314     error = z2_init();
 315     if ( error == 0 )
 316     {
 317         printk( KERN_INFO DEVICE_NAME ": loaded as module\n" );
 318     }
 319
 320     return error;
 321 }
 322
 323 void
 324 cleanup_module( void )
 325 {
 326     int i, j;
 327
 328     if ( unregister_blkdev( MAJOR_NR, DEVICE_NAME ) != 0 )
 329         printk( KERN_ERR DEVICE_NAME ": unregister of device failed\n");
 330
 331     if ( current_device != -1 )
 332     {
 333         i = 0;
 334
 335         for ( j = 0 ; j < z2_count; j++ )
 336         {
 337             set_bit( i++, zorro_unused_z2ram );
 338         }
 339
 340         for ( j = 0 ; j < chip_count; j++ )
 341         {
 342             if ( z2ram_map[ i ] )
 343             {
 344                 amiga_chip_free( (void *) z2ram_map[ i++ ] );
 345             }
 346         }
 347
 348         if ( z2ram_map != NULL )
 349         {
 350             kfree( z2ram_map );
 351         }
 352     }
 353
 354     return;
 355 }
 356 #endif