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