linux/drivers/block/z2ram.c
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   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
  44extern int m68k_realnum_memory;
  45extern 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
  58static u_long *z2ram_map    = NULL;
  59static u_long z2ram_size    = 0;
  60static int z2_count         = 0;
  61static int chip_count       = 0;
  62static int list_count       = 0;
  63static int current_device   = -1;
  64
  65static DEFINE_SPINLOCK(z2ram_lock);
  66
  67static struct gendisk *z2ram_gendisk;
  68
  69static 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
 104static void
 105get_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
 123static void
 124get_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
 144static 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
 298err_out_kfree:
 299    kfree(z2ram_map);
 300err_out:
 301    return rc;
 302}
 303
 304static int
 305z2_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
 317static const struct block_device_operations z2_fops =
 318{
 319        .owner          = THIS_MODULE,
 320        .open           = z2_open,
 321        .release        = z2_release,
 322};
 323
 324static struct kobject *z2_find(dev_t dev, int *part, void *data)
 325{
 326        *part = 0;
 327        return get_disk(z2ram_gendisk);
 328}
 329
 330static struct request_queue *z2_queue;
 331
 332static int __init 
 333z2_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
 365out_queue:
 366    put_disk(z2ram_gendisk);
 367out_disk:
 368    unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
 369err:
 370    return ret;
 371}
 372
 373static 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
 408module_init(z2_init);
 409module_exit(z2_exit);
 410MODULE_LICENSE("GPL");
 411