kernel/drivers/block/z2ram.c
2024-07-22 17:22:30 +08:00

412 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/blk-mq.h>
#include <linux/bitops.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/pgtable.h>
#include <asm/setup.h>
#include <asm/amigahw.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[Z2MINOR_COUNT];
static blk_status_t z2_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct request *req = bd->rq;
unsigned long start = blk_rq_pos(req) << 9;
unsigned long len = blk_rq_cur_bytes(req);
blk_mq_start_request(req);
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));
return BLK_STS_IOERR;
}
spin_lock_irq(&z2ram_lock);
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;
}
spin_unlock_irq(&z2ram_lock);
blk_mq_end_request(req, BLK_STS_OK);
return BLK_STS_OK;
}
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_wt(paddr, size);
#else
vaddr =
(unsigned long)z_remap_nocache_nonser(paddr, size);
#endif
z2ram_map =
kmalloc_array(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)
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)
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[device], 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 blk_mq_tag_set tag_set;
static const struct blk_mq_ops z2_mq_ops = {
.queue_rq = z2_queue_rq,
};
static int z2ram_register_disk(int minor)
{
struct gendisk *disk;
disk = blk_mq_alloc_disk(&tag_set, NULL);
if (IS_ERR(disk))
return PTR_ERR(disk);
disk->major = Z2RAM_MAJOR;
disk->first_minor = minor;
disk->minors = 1;
disk->fops = &z2_fops;
if (minor)
sprintf(disk->disk_name, "z2ram%d", minor);
else
sprintf(disk->disk_name, "z2ram");
z2ram_gendisk[minor] = disk;
add_disk(disk);
return 0;
}
static int __init z2_init(void)
{
int ret, i;
if (!MACH_IS_AMIGA)
return -ENODEV;
if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
return -EBUSY;
tag_set.ops = &z2_mq_ops;
tag_set.nr_hw_queues = 1;
tag_set.nr_maps = 1;
tag_set.queue_depth = 16;
tag_set.numa_node = NUMA_NO_NODE;
tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
ret = blk_mq_alloc_tag_set(&tag_set);
if (ret)
goto out_unregister_blkdev;
for (i = 0; i < Z2MINOR_COUNT; i++) {
ret = z2ram_register_disk(i);
if (ret && i == 0)
goto out_free_tagset;
}
return 0;
out_free_tagset:
blk_mq_free_tag_set(&tag_set);
out_unregister_blkdev:
unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
return ret;
}
static void __exit z2_exit(void)
{
int i, j;
unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
for (i = 0; i < Z2MINOR_COUNT; i++) {
del_gendisk(z2ram_gendisk[i]);
blk_cleanup_queue(z2ram_gendisk[i]->queue);
put_disk(z2ram_gendisk[i]);
}
blk_mq_free_tag_set(&tag_set);
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");