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