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