diff options
Diffstat (limited to 'arch/m68k/emu/nfblock.c')
| -rw-r--r-- | arch/m68k/emu/nfblock.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/arch/m68k/emu/nfblock.c b/arch/m68k/emu/nfblock.c new file mode 100644 index 0000000000..a708fbd5a8 --- /dev/null +++ b/arch/m68k/emu/nfblock.c @@ -0,0 +1,192 @@ +/* + * 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"); |