WSL2-Linux-Kernel/drivers/block/z2ram.c

419 строки
9.2 KiB
C

/*
** z2ram - Amiga pseudo-driver to access 16bit-RAM in ZorroII space
** as a block device, to be used as a RAM disk or swap space
**
** Copyright (C) 1994 by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)
**
** ++Geert: support for zorro_unused_z2ram, better range checking
** ++roman: translate accesses via an array
** ++Milan: support for ChipRAM usage
** ++yambo: converted to 2.0 kernel
** ++yambo: modularized and support added for 3 minor devices including:
** MAJOR MINOR DESCRIPTION
** ----- ----- ----------------------------------------------
** 37 0 Use Zorro II and Chip ram
** 37 1 Use only Zorro II ram
** 37 2 Use only Chip ram
** 37 4-7 Use memory list entry 1-4 (first is 0)
** ++jskov: support for 1-4th memory list entry.
**
** Permission to use, copy, modify, and distribute this software and its
** documentation for any purpose and without fee is hereby granted, provided
** that the above copyright notice appear in all copies and that both that
** copyright notice and this permission notice appear in supporting
** documentation. This software is provided "as is" without express or
** implied warranty.
*/
#define DEVICE_NAME "Z2RAM"
#include <linux/major.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/bitops.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <asm/setup.h>
#include <asm/amigahw.h>
#include <asm/pgtable.h>
#include <linux/zorro.h>
#define Z2MINOR_COMBINED (0)
#define Z2MINOR_Z2ONLY (1)
#define Z2MINOR_CHIPONLY (2)
#define Z2MINOR_MEMLIST1 (4)
#define Z2MINOR_MEMLIST2 (5)
#define Z2MINOR_MEMLIST3 (6)
#define Z2MINOR_MEMLIST4 (7)
#define Z2MINOR_COUNT (8) /* Move this down when adding a new minor */
#define Z2RAM_CHUNK1024 ( Z2RAM_CHUNKSIZE >> 10 )
static DEFINE_MUTEX(z2ram_mutex);
static u_long *z2ram_map = NULL;
static u_long z2ram_size = 0;
static int z2_count = 0;
static int chip_count = 0;
static int list_count = 0;
static int current_device = -1;
static DEFINE_SPINLOCK(z2ram_lock);
static struct gendisk *z2ram_gendisk;
static void do_z2_request(struct request_queue *q)
{
struct request *req;
req = blk_fetch_request(q);
while (req) {
unsigned long start = blk_rq_pos(req) << 9;
unsigned long len = blk_rq_cur_bytes(req);
blk_status_t err = BLK_STS_OK;
if (start + len > z2ram_size) {
pr_err(DEVICE_NAME ": bad access: block=%llu, "
"count=%u\n",
(unsigned long long)blk_rq_pos(req),
blk_rq_cur_sectors(req));
err = BLK_STS_IOERR;
goto done;
}
while (len) {
unsigned long addr = start & Z2RAM_CHUNKMASK;
unsigned long size = Z2RAM_CHUNKSIZE - addr;
void *buffer = bio_data(req->bio);
if (len < size)
size = len;
addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
if (rq_data_dir(req) == READ)
memcpy(buffer, (char *)addr, size);
else
memcpy((char *)addr, buffer, size);
start += size;
len -= size;
}
done:
if (!__blk_end_request_cur(req, err))
req = blk_fetch_request(q);
}
}
static void
get_z2ram( void )
{
int i;
for ( i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++ )
{
if ( test_bit( i, zorro_unused_z2ram ) )
{
z2_count++;
z2ram_map[z2ram_size++] = (unsigned long)ZTWO_VADDR(Z2RAM_START) +
(i << Z2RAM_CHUNKSHIFT);
clear_bit( i, zorro_unused_z2ram );
}
}
return;
}
static void
get_chipram( void )
{
while ( amiga_chip_avail() > ( Z2RAM_CHUNKSIZE * 4 ) )
{
chip_count++;
z2ram_map[ z2ram_size ] =
(u_long)amiga_chip_alloc( Z2RAM_CHUNKSIZE, "z2ram" );
if ( z2ram_map[ z2ram_size ] == 0 )
{
break;
}
z2ram_size++;
}
return;
}
static int z2_open(struct block_device *bdev, fmode_t mode)
{
int device;
int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
sizeof( z2ram_map[0] );
int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
sizeof( z2ram_map[0] );
int rc = -ENOMEM;
device = MINOR(bdev->bd_dev);
mutex_lock(&z2ram_mutex);
if ( current_device != -1 && current_device != device )
{
rc = -EBUSY;
goto err_out;
}
if ( current_device == -1 )
{
z2_count = 0;
chip_count = 0;
list_count = 0;
z2ram_size = 0;
/* Use a specific list entry. */
if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
int index = device - Z2MINOR_MEMLIST1 + 1;
unsigned long size, paddr, vaddr;
if (index >= m68k_realnum_memory) {
printk( KERN_ERR DEVICE_NAME
": no such entry in z2ram_map\n" );
goto err_out;
}
paddr = m68k_memory[index].addr;
size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
#ifdef __powerpc__
/* FIXME: ioremap doesn't build correct memory tables. */
{
vfree(vmalloc (size));
}
vaddr = (unsigned long) __ioremap (paddr, size,
_PAGE_WRITETHRU);
#else
vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
#endif
z2ram_map =
kmalloc((size/Z2RAM_CHUNKSIZE)*sizeof(z2ram_map[0]),
GFP_KERNEL);
if ( z2ram_map == NULL )
{
printk( KERN_ERR DEVICE_NAME
": cannot get mem for z2ram_map\n" );
goto err_out;
}
while (size) {
z2ram_map[ z2ram_size++ ] = vaddr;
size -= Z2RAM_CHUNKSIZE;
vaddr += Z2RAM_CHUNKSIZE;
list_count++;
}
if ( z2ram_size != 0 )
printk( KERN_INFO DEVICE_NAME
": using %iK List Entry %d Memory\n",
list_count * Z2RAM_CHUNK1024, index );
} else
switch ( device )
{
case Z2MINOR_COMBINED:
z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
if ( z2ram_map == NULL )
{
printk( KERN_ERR DEVICE_NAME
": cannot get mem for z2ram_map\n" );
goto err_out;
}
get_z2ram();
get_chipram();
if ( z2ram_size != 0 )
printk( KERN_INFO DEVICE_NAME
": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
z2_count * Z2RAM_CHUNK1024,
chip_count * Z2RAM_CHUNK1024,
( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
break;
case Z2MINOR_Z2ONLY:
z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
if ( z2ram_map == NULL )
{
printk( KERN_ERR DEVICE_NAME
": cannot get mem for z2ram_map\n" );
goto err_out;
}
get_z2ram();
if ( z2ram_size != 0 )
printk( KERN_INFO DEVICE_NAME
": using %iK of Zorro II RAM\n",
z2_count * Z2RAM_CHUNK1024 );
break;
case Z2MINOR_CHIPONLY:
z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
if ( z2ram_map == NULL )
{
printk( KERN_ERR DEVICE_NAME
": cannot get mem for z2ram_map\n" );
goto err_out;
}
get_chipram();
if ( z2ram_size != 0 )
printk( KERN_INFO DEVICE_NAME
": using %iK Chip RAM\n",
chip_count * Z2RAM_CHUNK1024 );
break;
default:
rc = -ENODEV;
goto err_out;
break;
}
if ( z2ram_size == 0 )
{
printk( KERN_NOTICE DEVICE_NAME
": no unused ZII/Chip RAM found\n" );
goto err_out_kfree;
}
current_device = device;
z2ram_size <<= Z2RAM_CHUNKSHIFT;
set_capacity(z2ram_gendisk, z2ram_size >> 9);
}
mutex_unlock(&z2ram_mutex);
return 0;
err_out_kfree:
kfree(z2ram_map);
err_out:
mutex_unlock(&z2ram_mutex);
return rc;
}
static void
z2_release(struct gendisk *disk, fmode_t mode)
{
mutex_lock(&z2ram_mutex);
if ( current_device == -1 ) {
mutex_unlock(&z2ram_mutex);
return;
}
mutex_unlock(&z2ram_mutex);
/*
* FIXME: unmap memory
*/
}
static const struct block_device_operations z2_fops =
{
.owner = THIS_MODULE,
.open = z2_open,
.release = z2_release,
};
static struct kobject *z2_find(dev_t dev, int *part, void *data)
{
*part = 0;
return get_disk(z2ram_gendisk);
}
static struct request_queue *z2_queue;
static int __init
z2_init(void)
{
int ret;
if (!MACH_IS_AMIGA)
return -ENODEV;
ret = -EBUSY;
if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
goto err;
ret = -ENOMEM;
z2ram_gendisk = alloc_disk(1);
if (!z2ram_gendisk)
goto out_disk;
z2_queue = blk_init_queue(do_z2_request, &z2ram_lock);
if (!z2_queue)
goto out_queue;
z2ram_gendisk->major = Z2RAM_MAJOR;
z2ram_gendisk->first_minor = 0;
z2ram_gendisk->fops = &z2_fops;
sprintf(z2ram_gendisk->disk_name, "z2ram");
z2ram_gendisk->queue = z2_queue;
add_disk(z2ram_gendisk);
blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
z2_find, NULL, NULL);
return 0;
out_queue:
put_disk(z2ram_gendisk);
out_disk:
unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
err:
return ret;
}
static void __exit z2_exit(void)
{
int i, j;
blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT);
unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
del_gendisk(z2ram_gendisk);
put_disk(z2ram_gendisk);
blk_cleanup_queue(z2_queue);
if ( current_device != -1 )
{
i = 0;
for ( j = 0 ; j < z2_count; j++ )
{
set_bit( i++, zorro_unused_z2ram );
}
for ( j = 0 ; j < chip_count; j++ )
{
if ( z2ram_map[ i ] )
{
amiga_chip_free( (void *) z2ram_map[ i++ ] );
}
}
if ( z2ram_map != NULL )
{
kfree( z2ram_map );
}
}
return;
}
module_init(z2_init);
module_exit(z2_exit);
MODULE_LICENSE("GPL");