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