1 /* 2 * ARAnyM block device driver 3 * 4 * This file is subject to the terms and conditions of the GNU General Public 5 * License. See the file COPYING in the main directory of this archive 6 * for more details. 7 */ 8 9 #include <linux/module.h> 10 #include <linux/moduleparam.h> 11 #include <linux/init.h> 12 13 #include <linux/kernel.h> 14 #include <linux/errno.h> 15 #include <linux/types.h> 16 #include <linux/genhd.h> 17 #include <linux/blkdev.h> 18 #include <linux/hdreg.h> 19 #include <linux/slab.h> 20 21 #include <asm/natfeat.h> 22 23 static long nfhd_id; 24 25 enum { 26 /* emulation entry points */ 27 NFHD_READ_WRITE = 10, 28 NFHD_GET_CAPACITY = 14, 29 30 /* skip ACSI devices */ 31 NFHD_DEV_OFFSET = 8, 32 }; 33 34 static inline s32 nfhd_read_write(u32 major, u32 minor, u32 rwflag, u32 recno, 35 u32 count, u32 buf) 36 { 37 return nf_call(nfhd_id + NFHD_READ_WRITE, major, minor, rwflag, recno, 38 count, buf); 39 } 40 41 static inline s32 nfhd_get_capacity(u32 major, u32 minor, u32 *blocks, 42 u32 *blocksize) 43 { 44 return nf_call(nfhd_id + NFHD_GET_CAPACITY, major, minor, 45 virt_to_phys(blocks), virt_to_phys(blocksize)); 46 } 47 48 static LIST_HEAD(nfhd_list); 49 50 static int major_num; 51 module_param(major_num, int, 0); 52 53 struct nfhd_device { 54 struct list_head list; 55 int id; 56 u32 blocks, bsize; 57 int bshift; 58 struct request_queue *queue; 59 struct gendisk *disk; 60 }; 61 62 static void nfhd_make_request(struct request_queue *queue, struct bio *bio) 63 { 64 struct nfhd_device *dev = queue->queuedata; 65 struct bio_vec *bvec; 66 int i, dir, len, shift; 67 sector_t sec = bio->bi_sector; 68 69 dir = bio_data_dir(bio); 70 shift = dev->bshift; 71 bio_for_each_segment(bvec, bio, i) { 72 len = bvec->bv_len; 73 len >>= 9; 74 nfhd_read_write(dev->id, 0, dir, sec >> shift, len >> shift, 75 bvec_to_phys(bvec)); 76 sec += len; 77 } 78 bio_endio(bio, 0); 79 } 80 81 static int nfhd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 82 { 83 struct nfhd_device *dev = bdev->bd_disk->private_data; 84 85 geo->cylinders = dev->blocks >> (6 - dev->bshift); 86 geo->heads = 4; 87 geo->sectors = 16; 88 89 return 0; 90 } 91 92 static const struct block_device_operations nfhd_ops = { 93 .owner = THIS_MODULE, 94 .getgeo = nfhd_getgeo, 95 }; 96 97 static int __init nfhd_init_one(int id, u32 blocks, u32 bsize) 98 { 99 struct nfhd_device *dev; 100 int dev_id = id - NFHD_DEV_OFFSET; 101 102 pr_info("nfhd%u: found device with %u blocks (%u bytes)\n", dev_id, 103 blocks, bsize); 104 105 if (bsize < 512 || (bsize & (bsize - 1))) { 106 pr_warn("nfhd%u: invalid block size\n", dev_id); 107 return -EINVAL; 108 } 109 110 dev = kmalloc(sizeof(struct nfhd_device), GFP_KERNEL); 111 if (!dev) 112 goto out; 113 114 dev->id = id; 115 dev->blocks = blocks; 116 dev->bsize = bsize; 117 dev->bshift = ffs(bsize) - 10; 118 119 dev->queue = blk_alloc_queue(GFP_KERNEL); 120 if (dev->queue == NULL) 121 goto free_dev; 122 123 dev->queue->queuedata = dev; 124 blk_queue_make_request(dev->queue, nfhd_make_request); 125 blk_queue_logical_block_size(dev->queue, bsize); 126 127 dev->disk = alloc_disk(16); 128 if (!dev->disk) 129 goto free_queue; 130 131 dev->disk->major = major_num; 132 dev->disk->first_minor = dev_id * 16; 133 dev->disk->fops = &nfhd_ops; 134 dev->disk->private_data = dev; 135 sprintf(dev->disk->disk_name, "nfhd%u", dev_id); 136 set_capacity(dev->disk, (sector_t)blocks * (bsize / 512)); 137 dev->disk->queue = dev->queue; 138 139 add_disk(dev->disk); 140 141 list_add_tail(&dev->list, &nfhd_list); 142 143 return 0; 144 145 free_queue: 146 blk_cleanup_queue(dev->queue); 147 free_dev: 148 kfree(dev); 149 out: 150 return -ENOMEM; 151 } 152 153 static int __init nfhd_init(void) 154 { 155 u32 blocks, bsize; 156 int i; 157 158 nfhd_id = nf_get_id("XHDI"); 159 if (!nfhd_id) 160 return -ENODEV; 161 162 major_num = register_blkdev(major_num, "nfhd"); 163 if (major_num <= 0) { 164 pr_warn("nfhd: unable to get major number\n"); 165 return major_num; 166 } 167 168 for (i = NFHD_DEV_OFFSET; i < 24; i++) { 169 if (nfhd_get_capacity(i, 0, &blocks, &bsize)) 170 continue; 171 nfhd_init_one(i, blocks, bsize); 172 } 173 174 return 0; 175 } 176 177 static void __exit nfhd_exit(void) 178 { 179 struct nfhd_device *dev, *next; 180 181 list_for_each_entry_safe(dev, next, &nfhd_list, list) { 182 list_del(&dev->list); 183 del_gendisk(dev->disk); 184 put_disk(dev->disk); 185 blk_cleanup_queue(dev->queue); 186 kfree(dev); 187 } 188 unregister_blkdev(major_num, "nfhd"); 189 } 190 191 module_init(nfhd_init); 192 module_exit(nfhd_exit); 193 194 MODULE_LICENSE("GPL"); 195