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 z2_open(struct block_device *bdev, fmode_t mode)
 141 {
 142     int device;
 143     int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
 144         sizeof( z2ram_map[0] );
 145     int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
 146         sizeof( z2ram_map[0] );
 147     int rc = -ENOMEM;
 148
 149     device = MINOR(bdev->bd_dev);
 150
 151     if ( current_device != -1 && current_device != device )
 152     {
 153         rc = -EBUSY;
 154         goto err_out;
 155     }
 156
 157     if ( current_device == -1 )
 158     {
 159         z2_count   = 0;
 160         chip_count = 0;
 161         list_count = 0;
 162         z2ram_size = 0;
 163
 164         /* Use a specific list entry. */
 165         if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
 166                 int index = device - Z2MINOR_MEMLIST1 + 1;
 167                 unsigned long size, paddr, vaddr;
 168
 169                 if (index >= m68k_realnum_memory) {
 170                         printk( KERN_ERR DEVICE_NAME
 171                                 ": no such entry in z2ram_map\n" );
 172                         goto err_out;
 173                 }
 174
 175                 paddr = m68k_memory[index].addr;
 176                 size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
 177
 178 #ifdef __powerpc__
 179                 /* FIXME: ioremap doesn't build correct memory tables. */
 180                 {
 181                         vfree(vmalloc (size));
 182                 }
 183
 184                 vaddr = (unsigned long) __ioremap (paddr, size,
 185                                                    _PAGE_WRITETHRU);
 186
 187 #else
 188                 vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
 189 #endif
 190                 z2ram_map =
 191                         kmalloc((size/Z2RAM_CHUNKSIZE)*sizeof(z2ram_map[0]),
 192                                 GFP_KERNEL);
 193                 if ( z2ram_map == NULL )
 194                 {
 195                     printk( KERN_ERR DEVICE_NAME
 196                         ": cannot get mem for z2ram_map\n" );
 197                     goto err_out;
 198                 }
 199
 200                 while (size) {
 201                         z2ram_map[ z2ram_size++ ] = vaddr;
 202                         size -= Z2RAM_CHUNKSIZE;
 203                         vaddr += Z2RAM_CHUNKSIZE;
 204                         list_count++;
 205                 }
 206
 207                 if ( z2ram_size != 0 )
 208                     printk( KERN_INFO DEVICE_NAME
 209                         ": using %iK List Entry %d Memory\n",
 210                         list_count * Z2RAM_CHUNK1024, index );
 211         } else
 212
 213         switch ( device )
 214         {
 215             case Z2MINOR_COMBINED:
 216
 217                 z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
 218                 if ( z2ram_map == NULL )
 219                 {
 220                     printk( KERN_ERR DEVICE_NAME
 221                         ": cannot get mem for z2ram_map\n" );
 222                     goto err_out;
 223                 }
 224
 225                 get_z2ram();
 226                 get_chipram();
 227
 228                 if ( z2ram_size != 0 )
 229                     printk( KERN_INFO DEVICE_NAME
 230                         ": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
 231                         z2_count * Z2RAM_CHUNK1024,
 232                         chip_count * Z2RAM_CHUNK1024,
 233                         ( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
 234
 235             break;
 236
 237             case Z2MINOR_Z2ONLY:
 238                 z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
 239                 if ( z2ram_map == NULL )
 240                 {
 241                     printk( KERN_ERR DEVICE_NAME
 242                         ": cannot get mem for z2ram_map\n" );
 243                     goto err_out;
 244                 }
 245
 246                 get_z2ram();
 247
 248                 if ( z2ram_size != 0 )
 249                     printk( KERN_INFO DEVICE_NAME
 250                         ": using %iK of Zorro II RAM\n",
 251                         z2_count * Z2RAM_CHUNK1024 );
 252
 253             break;
 254
 255             case Z2MINOR_CHIPONLY:
 256                 z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
 257                 if ( z2ram_map == NULL )
 258                 {
 259                     printk( KERN_ERR DEVICE_NAME
 260                         ": cannot get mem for z2ram_map\n" );
 261                     goto err_out;
 262                 }
 263
 264                 get_chipram();
 265
 266                 if ( z2ram_size != 0 )
 267                     printk( KERN_INFO DEVICE_NAME
 268                         ": using %iK Chip RAM\n",
 269                         chip_count * Z2RAM_CHUNK1024 );
 270
 271             break;
 272
 273             default:
 274                 rc = -ENODEV;
 275                 goto err_out;
 276
 277             break;
 278         }
 279
 280         if ( z2ram_size == 0 )
 281         {
 282             printk( KERN_NOTICE DEVICE_NAME
 283                 ": no unused ZII/Chip RAM found\n" );
 284             goto err_out_kfree;
 285         }
 286
 287         current_device = device;
 288         z2ram_size <<= Z2RAM_CHUNKSHIFT;
 289         set_capacity(z2ram_gendisk, z2ram_size >> 9);
 290     }
 291
 292     return 0;
 293
 294 err_out_kfree:
 295     kfree(z2ram_map);
 296 err_out:
 297     return rc;
 298 }
 299
 300 static int
 301 z2_release(struct gendisk *disk, fmode_t mode)
 302 {
 303     if ( current_device == -1 )
 304         return 0;
 305
 306     /*
 307      * FIXME: unmap memory
 308      */
 309
 310     return 0;
 311 }
 312
 313 static struct block_device_operations z2_fops =
 314 {
 315         .owner          = THIS_MODULE,
 316         .open           = z2_open,
 317         .release        = z2_release,
 318 };
 319
 320 static struct kobject *z2_find(dev_t dev, int *part, void *data)
 321 {
 322         *part = 0;
 323         return get_disk(z2ram_gendisk);
 324 }
 325
 326 static struct request_queue *z2_queue;
 327
 328 static int __init
 329 z2_init(void)
 330 {
 331     int ret;
 332
 333     if (!MACH_IS_AMIGA)
 334         return -ENODEV;
 335
 336     ret = -EBUSY;
 337     if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
 338         goto err;
 339
 340     ret = -ENOMEM;
 341     z2ram_gendisk = alloc_disk(1);
 342     if (!z2ram_gendisk)
 343         goto out_disk;
 344
 345     z2_queue = blk_init_queue(do_z2_request, &z2ram_lock);
 346     if (!z2_queue)
 347         goto out_queue;
 348
 349     z2ram_gendisk->major = Z2RAM_MAJOR;
 350     z2ram_gendisk->first_minor = 0;
 351     z2ram_gendisk->fops = &z2_fops;
 352     sprintf(z2ram_gendisk->disk_name, "z2ram");
 353
 354     z2ram_gendisk->queue = z2_queue;
 355     add_disk(z2ram_gendisk);
 356     blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
 357                                 z2_find, NULL, NULL);
 358
 359     return 0;
 360
 361 out_queue:
 362     put_disk(z2ram_gendisk);
 363 out_disk:
 364     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
 365 err:
 366     return ret;
 367 }
 368
 369 static void __exit z2_exit(void)
 370 {
 371     int i, j;
 372     blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), 256);
 373     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
 374     del_gendisk(z2ram_gendisk);
 375     put_disk(z2ram_gendisk);
 376     blk_cleanup_queue(z2_queue);
 377
 378     if ( current_device != -1 )
 379     {
 380         i = 0;
 381
 382         for ( j = 0 ; j < z2_count; j++ )
 383         {
 384             set_bit( i++, zorro_unused_z2ram );
 385         }
 386
 387         for ( j = 0 ; j < chip_count; j++ )
 388         {
 389             if ( z2ram_map[ i ] )
 390             {
 391                 amiga_chip_free( (void *) z2ram_map[ i++ ] );
 392             }
 393         }
 394
 395         if ( z2ram_map != NULL )
 396         {
 397             kfree( z2ram_map );
 398         }
 399     }
 400
 401     return;
 402 }
 403
 404 module_init(z2_init);
 405 module_exit(z2_exit);
 406 MODULE_LICENSE("GPL");