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 #include <linux/mutex.h>
  37 #include <linux/slab.h>
  38
  39 #include <asm/setup.h>
  40 #include <asm/amigahw.h>
  41 #include <asm/pgtable.h>
  42
  43 #include <linux/zorro.h>
  44
  45
  46 extern int m68k_realnum_memory;
  47 extern struct mem_info m68k_memory[NUM_MEMINFO];
  48
  49 #define Z2MINOR_COMBINED      (0)
  50 #define Z2MINOR_Z2ONLY        (1)
  51 #define Z2MINOR_CHIPONLY      (2)
  52 #define Z2MINOR_MEMLIST1      (4)
  53 #define Z2MINOR_MEMLIST2      (5)
  54 #define Z2MINOR_MEMLIST3      (6)
  55 #define Z2MINOR_MEMLIST4      (7)
  56 #define Z2MINOR_COUNT         (8) /* Move this down when adding a new minor */
  57
  58 #define Z2RAM_CHUNK1024       ( Z2RAM_CHUNKSIZE >> 10 )
  59
  60 static DEFINE_MUTEX(z2ram_mutex);
  61 static u_long *z2ram_map    = NULL;
  62 static u_long z2ram_size    = 0;
  63 static int z2_count         = 0;
  64 static int chip_count       = 0;
  65 static int list_count       = 0;
  66 static int current_device   = -1;
  67
  68 static DEFINE_SPINLOCK(z2ram_lock);
  69
  70 static struct gendisk *z2ram_gendisk;
  71
  72 static void do_z2_request(struct request_queue *q)
  73 {
  74         struct request *req;
  75
  76         req = blk_fetch_request(q);
  77         while (req) {
  78                 unsigned long start = blk_rq_pos(req) << 9;
  79                 unsigned long len  = blk_rq_cur_bytes(req);
  80                 int err = 0;
  81
  82                 if (start + len > z2ram_size) {
  83                         printk( KERN_ERR DEVICE_NAME ": bad access: block=%lu, count=%u\n",
  84                                 blk_rq_pos(req), blk_rq_cur_sectors(req));
  85                         err = -EIO;
  86                         goto done;
  87                 }
  88                 while (len) {
  89                         unsigned long addr = start & Z2RAM_CHUNKMASK;
  90                         unsigned long size = Z2RAM_CHUNKSIZE - addr;
  91                         if (len < size)
  92                                 size = len;
  93                         addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
  94                         if (rq_data_dir(req) == READ)
  95                                 memcpy(req->buffer, (char *)addr, size);
  96                         else
  97                                 memcpy((char *)addr, req->buffer, size);
  98                         start += size;
  99                         len -= size;
 100                 }
 101         done:
 102                 if (!__blk_end_request_cur(req, err))
 103                         req = blk_fetch_request(q);
 104         }
 105 }
 106
 107 static void
 108 get_z2ram( void )
 109 {
 110     int i;
 111
 112     for ( i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++ )
 113     {
 114         if ( test_bit( i, zorro_unused_z2ram ) )
 115         {
 116             z2_count++;
 117             z2ram_map[ z2ram_size++ ] =
 118                 ZTWO_VADDR( Z2RAM_START ) + ( i << Z2RAM_CHUNKSHIFT );
 119             clear_bit( i, zorro_unused_z2ram );
 120         }
 121     }
 122
 123     return;
 124 }
 125
 126 static void
 127 get_chipram( void )
 128 {
 129
 130     while ( amiga_chip_avail() > ( Z2RAM_CHUNKSIZE * 4 ) )
 131     {
 132         chip_count++;
 133         z2ram_map[ z2ram_size ] =
 134             (u_long)amiga_chip_alloc( Z2RAM_CHUNKSIZE, "z2ram" );
 135
 136         if ( z2ram_map[ z2ram_size ] == 0 )
 137         {
 138             break;
 139         }
 140
 141         z2ram_size++;
 142     }
 143
 144     return;
 145 }
 146
 147 static int z2_open(struct block_device *bdev, fmode_t mode)
 148 {
 149     int device;
 150     int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
 151         sizeof( z2ram_map[0] );
 152     int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
 153         sizeof( z2ram_map[0] );
 154     int rc = -ENOMEM;
 155
 156     device = MINOR(bdev->bd_dev);
 157
 158     mutex_lock(&z2ram_mutex);
 159     if ( current_device != -1 && current_device != device )
 160     {
 161         rc = -EBUSY;
 162         goto err_out;
 163     }
 164
 165     if ( current_device == -1 )
 166     {
 167         z2_count   = 0;
 168         chip_count = 0;
 169         list_count = 0;
 170         z2ram_size = 0;
 171
 172         /* Use a specific list entry. */
 173         if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
 174                 int index = device - Z2MINOR_MEMLIST1 + 1;
 175                 unsigned long size, paddr, vaddr;
 176
 177                 if (index >= m68k_realnum_memory) {
 178                         printk( KERN_ERR DEVICE_NAME
 179                                 ": no such entry in z2ram_map\n" );
 180                         goto err_out;
 181                 }
 182
 183                 paddr = m68k_memory[index].addr;
 184                 size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
 185
 186 #ifdef __powerpc__
 187                 /* FIXME: ioremap doesn't build correct memory tables. */
 188                 {
 189                         vfree(vmalloc (size));
 190                 }
 191
 192                 vaddr = (unsigned long) __ioremap (paddr, size,
 193                                                    _PAGE_WRITETHRU);
 194
 195 #else
 196                 vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
 197 #endif
 198                 z2ram_map =
 199                         kmalloc((size/Z2RAM_CHUNKSIZE)*sizeof(z2ram_map[0]),
 200                                 GFP_KERNEL);
 201                 if ( z2ram_map == NULL )
 202                 {
 203                     printk( KERN_ERR DEVICE_NAME
 204                         ": cannot get mem for z2ram_map\n" );
 205                     goto err_out;
 206                 }
 207
 208                 while (size) {
 209                         z2ram_map[ z2ram_size++ ] = vaddr;
 210                         size -= Z2RAM_CHUNKSIZE;
 211                         vaddr += Z2RAM_CHUNKSIZE;
 212                         list_count++;
 213                 }
 214
 215                 if ( z2ram_size != 0 )
 216                     printk( KERN_INFO DEVICE_NAME
 217                         ": using %iK List Entry %d Memory\n",
 218                         list_count * Z2RAM_CHUNK1024, index );
 219         } else
 220
 221         switch ( device )
 222         {
 223             case Z2MINOR_COMBINED:
 224
 225                 z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
 226                 if ( z2ram_map == NULL )
 227                 {
 228                     printk( KERN_ERR DEVICE_NAME
 229                         ": cannot get mem for z2ram_map\n" );
 230                     goto err_out;
 231                 }
 232
 233                 get_z2ram();
 234                 get_chipram();
 235
 236                 if ( z2ram_size != 0 )
 237                     printk( KERN_INFO DEVICE_NAME
 238                         ": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
 239                         z2_count * Z2RAM_CHUNK1024,
 240                         chip_count * Z2RAM_CHUNK1024,
 241                         ( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
 242
 243             break;
 244
 245             case Z2MINOR_Z2ONLY:
 246                 z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
 247                 if ( z2ram_map == NULL )
 248                 {
 249                     printk( KERN_ERR DEVICE_NAME
 250                         ": cannot get mem for z2ram_map\n" );
 251                     goto err_out;
 252                 }
 253
 254                 get_z2ram();
 255
 256                 if ( z2ram_size != 0 )
 257                     printk( KERN_INFO DEVICE_NAME
 258                         ": using %iK of Zorro II RAM\n",
 259                         z2_count * Z2RAM_CHUNK1024 );
 260
 261             break;
 262
 263             case Z2MINOR_CHIPONLY:
 264                 z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
 265                 if ( z2ram_map == NULL )
 266                 {
 267                     printk( KERN_ERR DEVICE_NAME
 268                         ": cannot get mem for z2ram_map\n" );
 269                     goto err_out;
 270                 }
 271
 272                 get_chipram();
 273
 274                 if ( z2ram_size != 0 )
 275                     printk( KERN_INFO DEVICE_NAME
 276                         ": using %iK Chip RAM\n",
 277                         chip_count * Z2RAM_CHUNK1024 );
 278
 279             break;
 280
 281             default:
 282                 rc = -ENODEV;
 283                 goto err_out;
 284
 285             break;
 286         }
 287
 288         if ( z2ram_size == 0 )
 289         {
 290             printk( KERN_NOTICE DEVICE_NAME
 291                 ": no unused ZII/Chip RAM found\n" );
 292             goto err_out_kfree;
 293         }
 294
 295         current_device = device;
 296         z2ram_size <<= Z2RAM_CHUNKSHIFT;
 297         set_capacity(z2ram_gendisk, z2ram_size >> 9);
 298     }
 299
 300     mutex_unlock(&z2ram_mutex);
 301     return 0;
 302
 303 err_out_kfree:
 304     kfree(z2ram_map);
 305 err_out:
 306     mutex_unlock(&z2ram_mutex);
 307     return rc;
 308 }
 309
 310 static int
 311 z2_release(struct gendisk *disk, fmode_t mode)
 312 {
 313     mutex_lock(&z2ram_mutex);
 314     if ( current_device == -1 ) {
 315         mutex_unlock(&z2ram_mutex);
 316         return 0;
 317     }
 318     mutex_unlock(&z2ram_mutex);
 319     /*
 320      * FIXME: unmap memory
 321      */
 322
 323     return 0;
 324 }
 325
 326 static const struct block_device_operations z2_fops =
 327 {
 328         .owner          = THIS_MODULE,
 329         .open           = z2_open,
 330         .release        = z2_release,
 331 };
 332
 333 static struct kobject *z2_find(dev_t dev, int *part, void *data)
 334 {
 335         *part = 0;
 336         return get_disk(z2ram_gendisk);
 337 }
 338
 339 static struct request_queue *z2_queue;
 340
 341 static int __init
 342 z2_init(void)
 343 {
 344     int ret;
 345
 346     if (!MACH_IS_AMIGA)
 347         return -ENODEV;
 348
 349     ret = -EBUSY;
 350     if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
 351         goto err;
 352
 353     ret = -ENOMEM;
 354     z2ram_gendisk = alloc_disk(1);
 355     if (!z2ram_gendisk)
 356         goto out_disk;
 357
 358     z2_queue = blk_init_queue(do_z2_request, &z2ram_lock);
 359     if (!z2_queue)
 360         goto out_queue;
 361
 362     z2ram_gendisk->major = Z2RAM_MAJOR;
 363     z2ram_gendisk->first_minor = 0;
 364     z2ram_gendisk->fops = &z2_fops;
 365     sprintf(z2ram_gendisk->disk_name, "z2ram");
 366
 367     z2ram_gendisk->queue = z2_queue;
 368     add_disk(z2ram_gendisk);
 369     blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
 370                                 z2_find, NULL, NULL);
 371
 372     return 0;
 373
 374 out_queue:
 375     put_disk(z2ram_gendisk);
 376 out_disk:
 377     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
 378 err:
 379     return ret;
 380 }
 381
 382 static void __exit z2_exit(void)
 383 {
 384     int i, j;
 385     blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT);
 386     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
 387     del_gendisk(z2ram_gendisk);
 388     put_disk(z2ram_gendisk);
 389     blk_cleanup_queue(z2_queue);
 390
 391     if ( current_device != -1 )
 392     {
 393         i = 0;
 394
 395         for ( j = 0 ; j < z2_count; j++ )
 396         {
 397             set_bit( i++, zorro_unused_z2ram );
 398         }
 399
 400         for ( j = 0 ; j < chip_count; j++ )
 401         {
 402             if ( z2ram_map[ i ] )
 403             {
 404                 amiga_chip_free( (void *) z2ram_map[ i++ ] );
 405             }
 406         }
 407
 408         if ( z2ram_map != NULL )
 409         {
 410             kfree( z2ram_map );
 411         }
 412     }
 413
 414     return;
 415 }
 416
 417 module_init(z2_init);
 418 module_exit(z2_exit);
 419 MODULE_LICENSE("GPL");