linux/drivers/block/z2ram.c
Jens Axboe b4f42e2831 block: remove struct request buffer member
This was used in the olden days, back when onions were proper
yellow. Basically it mapped to the current buffer to be
transferred. With highmem being added more than a decade ago,
most drivers map pages out of a bio, and rq->buffer isn't
pointing at anything valid.

Convert old style drivers to just use bio_data().

For the discard payload use case, just reference the page
in the bio.

Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-15 14:03:02 -06:00

419 lines
9.1 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);
int err = 0;
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 = -EIO;
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");