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 **          37     4-7     Use memory list entry 1-4 (first is 0)
  18 ** ++jskov: support for 1-4th memory list entry.
  19 **
  20 ** Permission to use, copy, modify, and distribute this software and its
  21 ** documentation for any purpose and without fee is hereby granted, provided
  22 ** that the above copyright notice appear in all copies and that both that
  23 ** copyright notice and this permission notice appear in supporting
  24 ** documentation.  This software is provided "as is" without express or
  25 ** implied warranty.
  26 */
  27
  28 #define DEVICE_NAME "Z2RAM"
  29
  30 #include <linux/major.h>
  31 #include <linux/vmalloc.h>
  32 #include <linux/init.h>
  33 #include <linux/module.h>
  34 #include <linux/blkdev.h>
  35 #include <linux/bitops.h>
  36
  37 #include <asm/setup.h>
  38 #include <asm/amigahw.h>
  39 #include <asm/pgtable.h>
  40
  41 #include <linux/zorro.h>
  42
  43
  44 extern int m68k_realnum_memory;
  45 extern struct mem_info m68k_memory[NUM_MEMINFO];
  46
  47 #define Z2MINOR_COMBINED      (0)
  48 #define Z2MINOR_Z2ONLY        (1)
  49 #define Z2MINOR_CHIPONLY      (2)
  50 #define Z2MINOR_MEMLIST1      (4)
  51 #define Z2MINOR_MEMLIST2      (5)
  52 #define Z2MINOR_MEMLIST3      (6)
  53 #define Z2MINOR_MEMLIST4      (7)
  54 #define Z2MINOR_COUNT         (8) /* Move this down when adding a new minor */
  55
  56 #define Z2RAM_CHUNK1024       ( Z2RAM_CHUNKSIZE >> 10 )
  57
  58 static u_long *z2ram_map    = NULL;
  59 static u_long z2ram_size    = 0;
  60 static int z2_count         = 0;
  61 static int chip_count       = 0;
  62 static int list_count       = 0;
  63 static int current_device   = -1;
  64
  65 static DEFINE_SPINLOCK(z2ram_lock);
  66
  67 static struct block_device_operations z2_fops;
  68 static struct gendisk *z2ram_gendisk;
  69
  70 static void do_z2_request(struct request_queue *q)
  71 {
  72         struct request *req;
  73         while ((req = elv_next_request(q)) != NULL) {
  74                 unsigned long start = req->sector << 9;
  75                 unsigned long len  = req->current_nr_sectors << 9;
  76
  77                 if (start + len > z2ram_size) {
  78                         printk( KERN_ERR DEVICE_NAME ": bad access: block=%lu, count=%u\n",
  79                                 req->sector, req->current_nr_sectors);
  80                         end_request(req, 0);
  81                         continue;
  82                 }
  83                 while (len) {
  84                         unsigned long addr = start & Z2RAM_CHUNKMASK;
  85                         unsigned long size = Z2RAM_CHUNKSIZE - addr;
  86                         if (len < size)
  87                                 size = len;
  88                         addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
  89                         if (rq_data_dir(req) == READ)
  90                                 memcpy(req->buffer, (char *)addr, size);
  91                         else
  92                                 memcpy((char *)addr, req->buffer, size);
  93                         start += size;
  94                         len -= size;
  95                 }
  96                 end_request(req, 1);
  97         }
  98 }
  99
 100 static void
 101 get_z2ram( void )
 102 {
 103     int i;
 104
 105     for ( i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++ )
 106     {
 107         if ( test_bit( i, zorro_unused_z2ram ) )
 108         {
 109             z2_count++;
 110             z2ram_map[ z2ram_size++ ] =
 111                 ZTWO_VADDR( Z2RAM_START ) + ( i << Z2RAM_CHUNKSHIFT );
 112             clear_bit( i, zorro_unused_z2ram );
 113         }
 114     }
 115
 116     return;
 117 }
 118
 119 static void
 120 get_chipram( void )
 121 {
 122
 123     while ( amiga_chip_avail() > ( Z2RAM_CHUNKSIZE * 4 ) )
 124     {
 125         chip_count++;
 126         z2ram_map[ z2ram_size ] =
 127             (u_long)amiga_chip_alloc( Z2RAM_CHUNKSIZE, "z2ram" );
 128
 129         if ( z2ram_map[ z2ram_size ] == 0 )
 130         {
 131             break;
 132         }
 133
 134         z2ram_size++;
 135     }
 136
 137     return;
 138 }
 139
 140 static int
 141 z2_open( struct inode *inode, struct file *filp )
 142 {
 143     int device;
 144     int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
 145         sizeof( z2ram_map[0] );
 146     int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
 147         sizeof( z2ram_map[0] );
 148     int rc = -ENOMEM;
 149
 150     device = iminor(inode);
 151
 152     if ( current_device != -1 && current_device != device )
 153     {
 154         rc = -EBUSY;
 155         goto err_out;
 156     }
 157
 158     if ( current_device == -1 )
 159     {
 160         z2_count   = 0;
 161         chip_count = 0;
 162         list_count = 0;
 163         z2ram_size = 0;
 164
 165         /* Use a specific list entry. */
 166         if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
 167                 int index = device - Z2MINOR_MEMLIST1 + 1;
 168                 unsigned long size, paddr, vaddr;
 169
 170                 if (index >= m68k_realnum_memory) {
 171                         printk( KERN_ERR DEVICE_NAME
 172                                 ": no such entry in z2ram_map\n" );
 173                         goto err_out;
 174                 }
 175
 176                 paddr = m68k_memory[index].addr;
 177                 size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
 178
 179 #ifdef __powerpc__
 180                 /* FIXME: ioremap doesn't build correct memory tables. */
 181                 {
 182                         vfree(vmalloc (size));
 183                 }
 184
 185                 vaddr = (unsigned long) __ioremap (paddr, size,
 186                                                    _PAGE_WRITETHRU);
 187
 188 #else
 189                 vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
 190 #endif
 191                 z2ram_map =
 192                         kmalloc((size/Z2RAM_CHUNKSIZE)*sizeof(z2ram_map[0]),
 193                                 GFP_KERNEL);
 194                 if ( z2ram_map == NULL )
 195                 {
 196                     printk( KERN_ERR DEVICE_NAME
 197                         ": cannot get mem for z2ram_map\n" );
 198                     goto err_out;
 199                 }
 200
 201                 while (size) {
 202                         z2ram_map[ z2ram_size++ ] = vaddr;
 203                         size -= Z2RAM_CHUNKSIZE;
 204                         vaddr += Z2RAM_CHUNKSIZE;
 205                         list_count++;
 206                 }
 207
 208                 if ( z2ram_size != 0 )
 209                     printk( KERN_INFO DEVICE_NAME
 210                         ": using %iK List Entry %d Memory\n",
 211                         list_count * Z2RAM_CHUNK1024, index );
 212         } else
 213
 214         switch ( device )
 215         {
 216             case Z2MINOR_COMBINED:
 217
 218                 z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
 219                 if ( z2ram_map == NULL )
 220                 {
 221                     printk( KERN_ERR DEVICE_NAME
 222                         ": cannot get mem for z2ram_map\n" );
 223                     goto err_out;
 224                 }
 225
 226                 get_z2ram();
 227                 get_chipram();
 228
 229                 if ( z2ram_size != 0 )
 230                     printk( KERN_INFO DEVICE_NAME
 231                         ": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
 232                         z2_count * Z2RAM_CHUNK1024,
 233                         chip_count * Z2RAM_CHUNK1024,
 234                         ( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
 235
 236             break;
 237
 238             case Z2MINOR_Z2ONLY:
 239                 z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
 240                 if ( z2ram_map == NULL )
 241                 {
 242                     printk( KERN_ERR DEVICE_NAME
 243                         ": cannot get mem for z2ram_map\n" );
 244                     goto err_out;
 245                 }
 246
 247                 get_z2ram();
 248
 249                 if ( z2ram_size != 0 )
 250                     printk( KERN_INFO DEVICE_NAME
 251                         ": using %iK of Zorro II RAM\n",
 252                         z2_count * Z2RAM_CHUNK1024 );
 253
 254             break;
 255
 256             case Z2MINOR_CHIPONLY:
 257                 z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
 258                 if ( z2ram_map == NULL )
 259                 {
 260                     printk( KERN_ERR DEVICE_NAME
 261                         ": cannot get mem for z2ram_map\n" );
 262                     goto err_out;
 263                 }
 264
 265                 get_chipram();
 266
 267                 if ( z2ram_size != 0 )
 268                     printk( KERN_INFO DEVICE_NAME
 269                         ": using %iK Chip RAM\n",
 270                         chip_count * Z2RAM_CHUNK1024 );
 271
 272             break;
 273
 274             default:
 275                 rc = -ENODEV;
 276                 goto err_out;
 277
 278             break;
 279         }
 280
 281         if ( z2ram_size == 0 )
 282         {
 283             printk( KERN_NOTICE DEVICE_NAME
 284                 ": no unused ZII/Chip RAM found\n" );
 285             goto err_out_kfree;
 286         }
 287
 288         current_device = device;
 289         z2ram_size <<= Z2RAM_CHUNKSHIFT;
 290         set_capacity(z2ram_gendisk, z2ram_size >> 9);
 291     }
 292
 293     return 0;
 294
 295 err_out_kfree:
 296     kfree(z2ram_map);
 297 err_out:
 298     return rc;
 299 }
 300
 301 static int
 302 z2_release( struct inode *inode, struct file *filp )
 303 {
 304     if ( current_device == -1 )
 305         return 0;
 306
 307     /*
 308      * FIXME: unmap memory
 309      */
 310
 311     return 0;
 312 }
 313
 314 static struct block_device_operations z2_fops =
 315 {
 316         .owner          = THIS_MODULE,
 317         .open           = z2_open,
 318         .release        = z2_release,
 319 };
 320
 321 static struct kobject *z2_find(dev_t dev, int *part, void *data)
 322 {
 323         *part = 0;
 324         return get_disk(z2ram_gendisk);
 325 }
 326
 327 static struct request_queue *z2_queue;
 328
 329 static int __init
 330 z2_init(void)
 331 {
 332     int ret;
 333
 334     if (!MACH_IS_AMIGA)
 335         return -ENODEV;
 336
 337     ret = -EBUSY;
 338     if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
 339         goto err;
 340
 341     ret = -ENOMEM;
 342     z2ram_gendisk = alloc_disk(1);
 343     if (!z2ram_gendisk)
 344         goto out_disk;
 345
 346     z2_queue = blk_init_queue(do_z2_request, &z2ram_lock);
 347     if (!z2_queue)
 348         goto out_queue;
 349
 350     z2ram_gendisk->major = Z2RAM_MAJOR;
 351     z2ram_gendisk->first_minor = 0;
 352     z2ram_gendisk->fops = &z2_fops;
 353     sprintf(z2ram_gendisk->disk_name, "z2ram");
 354
 355     z2ram_gendisk->queue = z2_queue;
 356     add_disk(z2ram_gendisk);
 357     blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
 358                                 z2_find, NULL, NULL);
 359
 360     return 0;
 361
 362 out_queue:
 363     put_disk(z2ram_gendisk);
 364 out_disk:
 365     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
 366 err:
 367     return ret;
 368 }
 369
 370 static void __exit z2_exit(void)
 371 {
 372     int i, j;
 373     blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), 256);
 374     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
 375     del_gendisk(z2ram_gendisk);
 376     put_disk(z2ram_gendisk);
 377     blk_cleanup_queue(z2_queue);
 378
 379     if ( current_device != -1 )
 380     {
 381         i = 0;
 382
 383         for ( j = 0 ; j < z2_count; j++ )
 384         {
 385             set_bit( i++, zorro_unused_z2ram );
 386         }
 387
 388         for ( j = 0 ; j < chip_count; j++ )
 389         {
 390             if ( z2ram_map[ i ] )
 391             {
 392                 amiga_chip_free( (void *) z2ram_map[ i++ ] );
 393             }
 394         }
 395
 396         if ( z2ram_map != NULL )
 397         {
 398             kfree( z2ram_map );
 399         }
 400     }
 401
 402     return;
 403 }
 404
 405 module_init(z2_init);
 406 module_exit(z2_exit);
 407 MODULE_LICENSE("GPL");