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/*
* ARAnyM block device driver
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/blkdev.h>
#include <linux/hdreg.h>
#include <linux/slab.h>
#include <asm/natfeat.h>
static long nfhd_id;
enum {
/* emulation entry points */
NFHD_READ_WRITE = 10,
NFHD_GET_CAPACITY = 14,
/* skip ACSI devices */
NFHD_DEV_OFFSET = 8,
};
static inline s32 nfhd_read_write(u32 major, u32 minor, u32 rwflag, u32 recno,
u32 count, u32 buf)
{
return nf_call(nfhd_id + NFHD_READ_WRITE, major, minor, rwflag, recno,
count, buf);
}
static inline s32 nfhd_get_capacity(u32 major, u32 minor, u32 *blocks,
u32 *blocksize)
{
return nf_call(nfhd_id + NFHD_GET_CAPACITY, major, minor,
virt_to_phys(blocks), virt_to_phys(blocksize));
}
static LIST_HEAD(nfhd_list);
static int major_num;
module_param(major_num, int, 0);
struct nfhd_device {
struct list_head list;
int id;
u32 blocks, bsize;
int bshift;
struct gendisk *disk;
};
static void nfhd_submit_bio(struct bio *bio)
{
struct nfhd_device *dev = bio->bi_bdev->bd_disk->private_data;
struct bio_vec bvec;
struct bvec_iter iter;
int dir, len, shift;
sector_t sec = bio->bi_iter.bi_sector;
dir = bio_data_dir(bio);
shift = dev->bshift;
bio_for_each_segment(bvec, bio, iter) {
len = bvec.bv_len;
len >>= 9;
nfhd_read_write(dev->id, 0, dir, sec >> shift, len >> shift,
page_to_phys(bvec.bv_page) + bvec.bv_offset);
sec += len;
}
bio_endio(bio);
}
static int nfhd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct nfhd_device *dev = bdev->bd_disk->private_data;
geo->cylinders = dev->blocks >> (6 - dev->bshift);
geo->heads = 4;
geo->sectors = 16;
return 0;
}
static const struct block_device_operations nfhd_ops = {
.owner = THIS_MODULE,
.submit_bio = nfhd_submit_bio,
.getgeo = nfhd_getgeo,
};
static int __init nfhd_init_one(int id, u32 blocks, u32 bsize)
{
struct nfhd_device *dev;
int dev_id = id - NFHD_DEV_OFFSET;
int err = -ENOMEM;
pr_info("nfhd%u: found device with %u blocks (%u bytes)\n", dev_id,
blocks, bsize);
if (bsize < 512 || (bsize & (bsize - 1))) {
pr_warn("nfhd%u: invalid block size\n", dev_id);
return -EINVAL;
}
dev = kmalloc(sizeof(struct nfhd_device), GFP_KERNEL);
if (!dev)
goto out;
dev->id = id;
dev->blocks = blocks;
dev->bsize = bsize;
dev->bshift = ffs(bsize) - 10;
dev->disk = blk_alloc_disk(NUMA_NO_NODE);
if (!dev->disk)
goto free_dev;
dev->disk->major = major_num;
dev->disk->first_minor = dev_id * 16;
dev->disk->minors = 16;
dev->disk->fops = &nfhd_ops;
dev->disk->private_data = dev;
sprintf(dev->disk->disk_name, "nfhd%u", dev_id);
set_capacity(dev->disk, (sector_t)blocks * (bsize / 512));
blk_queue_logical_block_size(dev->disk->queue, bsize);
err = add_disk(dev->disk);
if (err)
goto out_cleanup_disk;
list_add_tail(&dev->list, &nfhd_list);
return 0;
out_cleanup_disk:
put_disk(dev->disk);
free_dev:
kfree(dev);
out:
return err;
}
static int __init nfhd_init(void)
{
u32 blocks, bsize;
int ret;
int i;
nfhd_id = nf_get_id("XHDI");
if (!nfhd_id)
return -ENODEV;
ret = register_blkdev(major_num, "nfhd");
if (ret < 0) {
pr_warn("nfhd: unable to get major number\n");
return ret;
}
if (!major_num)
major_num = ret;
for (i = NFHD_DEV_OFFSET; i < 24; i++) {
if (nfhd_get_capacity(i, 0, &blocks, &bsize))
continue;
nfhd_init_one(i, blocks, bsize);
}
return 0;
}
static void __exit nfhd_exit(void)
{
struct nfhd_device *dev, *next;
list_for_each_entry_safe(dev, next, &nfhd_list, list) {
list_del(&dev->list);
del_gendisk(dev->disk);
put_disk(dev->disk);
kfree(dev);
}
unregister_blkdev(major_num, "nfhd");
}
module_init(nfhd_init);
module_exit(nfhd_exit);
MODULE_LICENSE("GPL");
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