Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 1 | //#define DEBUG |
| 2 | #include <linux/spinlock.h> |
| 3 | #include <linux/blkdev.h> |
| 4 | #include <linux/hdreg.h> |
| 5 | #include <linux/virtio.h> |
| 6 | #include <linux/virtio_blk.h> |
Jens Axboe | 3d1266c | 2007-10-24 13:21:21 +0200 | [diff] [blame] | 7 | #include <linux/scatterlist.h> |
| 8 | |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 9 | #define PART_BITS 4 |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 10 | |
Christian Borntraeger | d50ed90 | 2008-02-01 09:05:00 +0100 | [diff] [blame] | 11 | static int major, index; |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 12 | |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 13 | struct virtio_blk |
| 14 | { |
| 15 | spinlock_t lock; |
| 16 | |
| 17 | struct virtio_device *vdev; |
| 18 | struct virtqueue *vq; |
| 19 | |
| 20 | /* The disk structure for the kernel. */ |
| 21 | struct gendisk *disk; |
| 22 | |
| 23 | /* Request tracking. */ |
| 24 | struct list_head reqs; |
| 25 | |
| 26 | mempool_t *pool; |
| 27 | |
Rusty Russell | 0864b79 | 2008-12-30 09:26:05 -0600 | [diff] [blame] | 28 | /* What host tells us, plus 2 for header & tailer. */ |
| 29 | unsigned int sg_elems; |
| 30 | |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 31 | /* Scatterlist: can be too big for stack. */ |
Rusty Russell | 0864b79 | 2008-12-30 09:26:05 -0600 | [diff] [blame] | 32 | struct scatterlist sg[/*sg_elems*/]; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 33 | }; |
| 34 | |
| 35 | struct virtblk_req |
| 36 | { |
| 37 | struct list_head list; |
| 38 | struct request *req; |
| 39 | struct virtio_blk_outhdr out_hdr; |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 40 | struct virtio_scsi_inhdr in_hdr; |
Rusty Russell | cb38fa2 | 2008-05-02 21:50:45 -0500 | [diff] [blame] | 41 | u8 status; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 42 | }; |
| 43 | |
Rusty Russell | 18445c4 | 2008-02-04 23:49:57 -0500 | [diff] [blame] | 44 | static void blk_done(struct virtqueue *vq) |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 45 | { |
| 46 | struct virtio_blk *vblk = vq->vdev->priv; |
| 47 | struct virtblk_req *vbr; |
| 48 | unsigned int len; |
| 49 | unsigned long flags; |
| 50 | |
| 51 | spin_lock_irqsave(&vblk->lock, flags); |
| 52 | while ((vbr = vblk->vq->vq_ops->get_buf(vblk->vq, &len)) != NULL) { |
Kiyoshi Ueda | 8316982 | 2008-10-01 10:11:20 -0400 | [diff] [blame] | 53 | int error; |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 54 | |
Rusty Russell | cb38fa2 | 2008-05-02 21:50:45 -0500 | [diff] [blame] | 55 | switch (vbr->status) { |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 56 | case VIRTIO_BLK_S_OK: |
Kiyoshi Ueda | 8316982 | 2008-10-01 10:11:20 -0400 | [diff] [blame] | 57 | error = 0; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 58 | break; |
| 59 | case VIRTIO_BLK_S_UNSUPP: |
Kiyoshi Ueda | 8316982 | 2008-10-01 10:11:20 -0400 | [diff] [blame] | 60 | error = -ENOTTY; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 61 | break; |
| 62 | default: |
Kiyoshi Ueda | 8316982 | 2008-10-01 10:11:20 -0400 | [diff] [blame] | 63 | error = -EIO; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 64 | break; |
| 65 | } |
| 66 | |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 67 | if (blk_pc_request(vbr->req)) { |
| 68 | vbr->req->resid_len = vbr->in_hdr.residual; |
| 69 | vbr->req->sense_len = vbr->in_hdr.sense_len; |
| 70 | vbr->req->errors = vbr->in_hdr.errors; |
| 71 | } |
| 72 | |
Tejun Heo | 40cbbb7 | 2009-04-23 11:05:19 +0900 | [diff] [blame] | 73 | __blk_end_request_all(vbr->req, error); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 74 | list_del(&vbr->list); |
| 75 | mempool_free(vbr, vblk->pool); |
| 76 | } |
| 77 | /* In case queue is stopped waiting for more buffers. */ |
| 78 | blk_start_queue(vblk->disk->queue); |
| 79 | spin_unlock_irqrestore(&vblk->lock, flags); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 80 | } |
| 81 | |
| 82 | static bool do_req(struct request_queue *q, struct virtio_blk *vblk, |
| 83 | struct request *req) |
| 84 | { |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 85 | unsigned long num, out = 0, in = 0; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 86 | struct virtblk_req *vbr; |
| 87 | |
| 88 | vbr = mempool_alloc(vblk->pool, GFP_ATOMIC); |
| 89 | if (!vbr) |
| 90 | /* When another request finishes we'll try again. */ |
| 91 | return false; |
| 92 | |
| 93 | vbr->req = req; |
| 94 | if (blk_fs_request(vbr->req)) { |
| 95 | vbr->out_hdr.type = 0; |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 96 | vbr->out_hdr.sector = blk_rq_pos(vbr->req); |
Fernando Luis Vázquez Cao | 766ca44 | 2008-08-14 09:59:13 +0200 | [diff] [blame] | 97 | vbr->out_hdr.ioprio = req_get_ioprio(vbr->req); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 98 | } else if (blk_pc_request(vbr->req)) { |
| 99 | vbr->out_hdr.type = VIRTIO_BLK_T_SCSI_CMD; |
| 100 | vbr->out_hdr.sector = 0; |
Fernando Luis Vázquez Cao | 766ca44 | 2008-08-14 09:59:13 +0200 | [diff] [blame] | 101 | vbr->out_hdr.ioprio = req_get_ioprio(vbr->req); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 102 | } else { |
| 103 | /* We don't put anything else in the queue. */ |
| 104 | BUG(); |
| 105 | } |
| 106 | |
| 107 | if (blk_barrier_rq(vbr->req)) |
| 108 | vbr->out_hdr.type |= VIRTIO_BLK_T_BARRIER; |
| 109 | |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 110 | sg_set_buf(&vblk->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr)); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 111 | |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 112 | /* |
| 113 | * If this is a packet command we need a couple of additional headers. |
| 114 | * Behind the normal outhdr we put a segment with the scsi command |
| 115 | * block, and before the normal inhdr we put the sense data and the |
| 116 | * inhdr with additional status information before the normal inhdr. |
| 117 | */ |
| 118 | if (blk_pc_request(vbr->req)) |
| 119 | sg_set_buf(&vblk->sg[out++], vbr->req->cmd, vbr->req->cmd_len); |
| 120 | |
| 121 | num = blk_rq_map_sg(q, vbr->req, vblk->sg + out); |
| 122 | |
| 123 | if (blk_pc_request(vbr->req)) { |
| 124 | sg_set_buf(&vblk->sg[num + out + in++], vbr->req->sense, 96); |
| 125 | sg_set_buf(&vblk->sg[num + out + in++], &vbr->in_hdr, |
| 126 | sizeof(vbr->in_hdr)); |
| 127 | } |
| 128 | |
| 129 | sg_set_buf(&vblk->sg[num + out + in++], &vbr->status, |
| 130 | sizeof(vbr->status)); |
| 131 | |
| 132 | if (num) { |
| 133 | if (rq_data_dir(vbr->req) == WRITE) { |
| 134 | vbr->out_hdr.type |= VIRTIO_BLK_T_OUT; |
| 135 | out += num; |
| 136 | } else { |
| 137 | vbr->out_hdr.type |= VIRTIO_BLK_T_IN; |
| 138 | in += num; |
| 139 | } |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 140 | } |
| 141 | |
| 142 | if (vblk->vq->vq_ops->add_buf(vblk->vq, vblk->sg, out, in, vbr)) { |
| 143 | mempool_free(vbr, vblk->pool); |
| 144 | return false; |
| 145 | } |
| 146 | |
| 147 | list_add_tail(&vbr->list, &vblk->reqs); |
| 148 | return true; |
| 149 | } |
| 150 | |
| 151 | static void do_virtblk_request(struct request_queue *q) |
| 152 | { |
Christoph Hellwig | 6c3b46f | 2009-05-18 14:38:28 +0200 | [diff] [blame] | 153 | struct virtio_blk *vblk = q->queuedata; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 154 | struct request *req; |
| 155 | unsigned int issued = 0; |
| 156 | |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 157 | while ((req = blk_peek_request(q)) != NULL) { |
Rusty Russell | 0864b79 | 2008-12-30 09:26:05 -0600 | [diff] [blame] | 158 | BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 159 | |
| 160 | /* If this request fails, stop queue and wait for something to |
| 161 | finish to restart it. */ |
| 162 | if (!do_req(q, vblk, req)) { |
| 163 | blk_stop_queue(q); |
| 164 | break; |
| 165 | } |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 166 | blk_start_request(req); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 167 | issued++; |
| 168 | } |
| 169 | |
| 170 | if (issued) |
| 171 | vblk->vq->vq_ops->kick(vblk->vq); |
| 172 | } |
| 173 | |
john cooper | 1d589bb | 2009-06-09 14:41:40 +0200 | [diff] [blame] | 174 | /* return ATA identify data |
| 175 | */ |
| 176 | static int virtblk_identify(struct gendisk *disk, void *argp) |
| 177 | { |
| 178 | struct virtio_blk *vblk = disk->private_data; |
| 179 | void *opaque; |
| 180 | int err = -ENOMEM; |
| 181 | |
| 182 | opaque = kmalloc(VIRTIO_BLK_ID_BYTES, GFP_KERNEL); |
| 183 | if (!opaque) |
| 184 | goto out; |
| 185 | |
| 186 | err = virtio_config_buf(vblk->vdev, VIRTIO_BLK_F_IDENTIFY, |
| 187 | offsetof(struct virtio_blk_config, identify), opaque, |
| 188 | VIRTIO_BLK_ID_BYTES); |
| 189 | |
| 190 | if (err) |
| 191 | goto out_kfree; |
| 192 | |
| 193 | if (copy_to_user(argp, opaque, VIRTIO_BLK_ID_BYTES)) |
| 194 | err = -EFAULT; |
| 195 | |
| 196 | out_kfree: |
| 197 | kfree(opaque); |
| 198 | out: |
| 199 | return err; |
| 200 | } |
| 201 | |
Al Viro | 4e10985 | 2008-03-02 10:22:33 -0500 | [diff] [blame] | 202 | static int virtblk_ioctl(struct block_device *bdev, fmode_t mode, |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 203 | unsigned cmd, unsigned long data) |
| 204 | { |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 205 | struct gendisk *disk = bdev->bd_disk; |
| 206 | struct virtio_blk *vblk = disk->private_data; |
john cooper | 1d589bb | 2009-06-09 14:41:40 +0200 | [diff] [blame] | 207 | void __user *argp = (void __user *)data; |
| 208 | |
| 209 | if (cmd == HDIO_GET_IDENTITY) |
| 210 | return virtblk_identify(disk, argp); |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 211 | |
| 212 | /* |
| 213 | * Only allow the generic SCSI ioctls if the host can support it. |
| 214 | */ |
| 215 | if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI)) |
Christoph Hellwig | d9ecdea | 2009-06-20 21:29:41 +0200 | [diff] [blame] | 216 | return -ENOTTY; |
Hannes Reinecke | 1cde26f | 2009-05-18 14:41:30 +0200 | [diff] [blame] | 217 | |
john cooper | 1d589bb | 2009-06-09 14:41:40 +0200 | [diff] [blame] | 218 | return scsi_cmd_ioctl(disk->queue, disk, mode, cmd, argp); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 219 | } |
| 220 | |
Christian Borntraeger | 135da0b | 2008-01-23 17:56:50 +0100 | [diff] [blame] | 221 | /* We provide getgeo only to please some old bootloader/partitioning tools */ |
| 222 | static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo) |
| 223 | { |
Ryan Harper | 48e4043 | 2008-04-16 13:56:37 -0500 | [diff] [blame] | 224 | struct virtio_blk *vblk = bd->bd_disk->private_data; |
| 225 | struct virtio_blk_geometry vgeo; |
| 226 | int err; |
| 227 | |
| 228 | /* see if the host passed in geometry config */ |
| 229 | err = virtio_config_val(vblk->vdev, VIRTIO_BLK_F_GEOMETRY, |
| 230 | offsetof(struct virtio_blk_config, geometry), |
| 231 | &vgeo); |
| 232 | |
| 233 | if (!err) { |
| 234 | geo->heads = vgeo.heads; |
| 235 | geo->sectors = vgeo.sectors; |
| 236 | geo->cylinders = vgeo.cylinders; |
| 237 | } else { |
| 238 | /* some standard values, similar to sd */ |
| 239 | geo->heads = 1 << 6; |
| 240 | geo->sectors = 1 << 5; |
| 241 | geo->cylinders = get_capacity(bd->bd_disk) >> 11; |
| 242 | } |
Christian Borntraeger | 135da0b | 2008-01-23 17:56:50 +0100 | [diff] [blame] | 243 | return 0; |
| 244 | } |
| 245 | |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 246 | static struct block_device_operations virtblk_fops = { |
Al Viro | 4e10985 | 2008-03-02 10:22:33 -0500 | [diff] [blame] | 247 | .locked_ioctl = virtblk_ioctl, |
Christian Borntraeger | 135da0b | 2008-01-23 17:56:50 +0100 | [diff] [blame] | 248 | .owner = THIS_MODULE, |
| 249 | .getgeo = virtblk_getgeo, |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 250 | }; |
| 251 | |
Christian Borntraeger | d50ed90 | 2008-02-01 09:05:00 +0100 | [diff] [blame] | 252 | static int index_to_minor(int index) |
| 253 | { |
| 254 | return index << PART_BITS; |
| 255 | } |
| 256 | |
Mike Frysinger | 98e9444 | 2009-05-18 03:39:09 -0400 | [diff] [blame] | 257 | static int __devinit virtblk_probe(struct virtio_device *vdev) |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 258 | { |
| 259 | struct virtio_blk *vblk; |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 260 | int err; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 261 | u64 cap; |
| 262 | u32 v; |
Rusty Russell | 0864b79 | 2008-12-30 09:26:05 -0600 | [diff] [blame] | 263 | u32 blk_size, sg_elems; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 264 | |
Christian Borntraeger | d50ed90 | 2008-02-01 09:05:00 +0100 | [diff] [blame] | 265 | if (index_to_minor(index) >= 1 << MINORBITS) |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 266 | return -ENOSPC; |
| 267 | |
Rusty Russell | 0864b79 | 2008-12-30 09:26:05 -0600 | [diff] [blame] | 268 | /* We need to know how many segments before we allocate. */ |
| 269 | err = virtio_config_val(vdev, VIRTIO_BLK_F_SEG_MAX, |
| 270 | offsetof(struct virtio_blk_config, seg_max), |
| 271 | &sg_elems); |
| 272 | if (err) |
| 273 | sg_elems = 1; |
| 274 | |
| 275 | /* We need an extra sg elements at head and tail. */ |
| 276 | sg_elems += 2; |
| 277 | vdev->priv = vblk = kmalloc(sizeof(*vblk) + |
| 278 | sizeof(vblk->sg[0]) * sg_elems, GFP_KERNEL); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 279 | if (!vblk) { |
| 280 | err = -ENOMEM; |
| 281 | goto out; |
| 282 | } |
| 283 | |
| 284 | INIT_LIST_HEAD(&vblk->reqs); |
| 285 | spin_lock_init(&vblk->lock); |
| 286 | vblk->vdev = vdev; |
Rusty Russell | 0864b79 | 2008-12-30 09:26:05 -0600 | [diff] [blame] | 287 | vblk->sg_elems = sg_elems; |
| 288 | sg_init_table(vblk->sg, vblk->sg_elems); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 289 | |
| 290 | /* We expect one virtqueue, for output. */ |
Michael S. Tsirkin | d2a7ddd | 2009-06-12 22:16:36 -0600 | [diff] [blame] | 291 | vblk->vq = virtio_find_single_vq(vdev, blk_done, "requests"); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 292 | if (IS_ERR(vblk->vq)) { |
| 293 | err = PTR_ERR(vblk->vq); |
| 294 | goto out_free_vblk; |
| 295 | } |
| 296 | |
| 297 | vblk->pool = mempool_create_kmalloc_pool(1,sizeof(struct virtblk_req)); |
| 298 | if (!vblk->pool) { |
| 299 | err = -ENOMEM; |
| 300 | goto out_free_vq; |
| 301 | } |
| 302 | |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 303 | /* FIXME: How many partitions? How long is a piece of string? */ |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 304 | vblk->disk = alloc_disk(1 << PART_BITS); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 305 | if (!vblk->disk) { |
| 306 | err = -ENOMEM; |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 307 | goto out_mempool; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 308 | } |
| 309 | |
| 310 | vblk->disk->queue = blk_init_queue(do_virtblk_request, &vblk->lock); |
| 311 | if (!vblk->disk->queue) { |
| 312 | err = -ENOMEM; |
| 313 | goto out_put_disk; |
| 314 | } |
| 315 | |
Christoph Hellwig | 6c3b46f | 2009-05-18 14:38:28 +0200 | [diff] [blame] | 316 | vblk->disk->queue->queuedata = vblk; |
Fernando Luis Vázquez Cao | 7d116b6 | 2008-10-27 18:45:15 +0900 | [diff] [blame] | 317 | queue_flag_set_unlocked(QUEUE_FLAG_VIRT, vblk->disk->queue); |
| 318 | |
Christian Borntraeger | d50ed90 | 2008-02-01 09:05:00 +0100 | [diff] [blame] | 319 | if (index < 26) { |
| 320 | sprintf(vblk->disk->disk_name, "vd%c", 'a' + index % 26); |
| 321 | } else if (index < (26 + 1) * 26) { |
| 322 | sprintf(vblk->disk->disk_name, "vd%c%c", |
| 323 | 'a' + index / 26 - 1, 'a' + index % 26); |
| 324 | } else { |
| 325 | const unsigned int m1 = (index / 26 - 1) / 26 - 1; |
| 326 | const unsigned int m2 = (index / 26 - 1) % 26; |
| 327 | const unsigned int m3 = index % 26; |
| 328 | sprintf(vblk->disk->disk_name, "vd%c%c%c", |
| 329 | 'a' + m1, 'a' + m2, 'a' + m3); |
| 330 | } |
| 331 | |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 332 | vblk->disk->major = major; |
Christian Borntraeger | d50ed90 | 2008-02-01 09:05:00 +0100 | [diff] [blame] | 333 | vblk->disk->first_minor = index_to_minor(index); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 334 | vblk->disk->private_data = vblk; |
| 335 | vblk->disk->fops = &virtblk_fops; |
Jeremy Katz | c483934 | 2008-03-02 17:00:15 -0500 | [diff] [blame] | 336 | vblk->disk->driverfs_dev = &vdev->dev; |
Christian Borntraeger | d50ed90 | 2008-02-01 09:05:00 +0100 | [diff] [blame] | 337 | index++; |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 338 | |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 339 | /* If barriers are supported, tell block layer that queue is ordered */ |
Rusty Russell | c45a681 | 2008-05-02 21:50:50 -0500 | [diff] [blame] | 340 | if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER)) |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 341 | blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_TAG, NULL); |
| 342 | |
Christian Borntraeger | 3ef5360 | 2008-05-16 11:17:03 +0200 | [diff] [blame] | 343 | /* If disk is read-only in the host, the guest should obey */ |
| 344 | if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO)) |
| 345 | set_disk_ro(vblk->disk, 1); |
| 346 | |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame] | 347 | /* Host must always specify the capacity. */ |
Rusty Russell | 72e61eb | 2008-05-02 21:50:49 -0500 | [diff] [blame] | 348 | vdev->config->get(vdev, offsetof(struct virtio_blk_config, capacity), |
| 349 | &cap, sizeof(cap)); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 350 | |
| 351 | /* If capacity is too big, truncate with warning. */ |
| 352 | if ((sector_t)cap != cap) { |
| 353 | dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n", |
| 354 | (unsigned long long)cap); |
| 355 | cap = (sector_t)-1; |
| 356 | } |
| 357 | set_capacity(vblk->disk, cap); |
| 358 | |
Rusty Russell | 0864b79 | 2008-12-30 09:26:05 -0600 | [diff] [blame] | 359 | /* We can handle whatever the host told us to handle. */ |
| 360 | blk_queue_max_phys_segments(vblk->disk->queue, vblk->sg_elems-2); |
| 361 | blk_queue_max_hw_segments(vblk->disk->queue, vblk->sg_elems-2); |
| 362 | |
Christoph Hellwig | 4eff3ca | 2009-07-17 21:47:45 -0600 | [diff] [blame] | 363 | /* No need to bounce any requests */ |
| 364 | blk_queue_bounce_limit(vblk->disk->queue, BLK_BOUNCE_ANY); |
| 365 | |
Rusty Russell | 4b7f7e2 | 2008-12-30 09:26:04 -0600 | [diff] [blame] | 366 | /* No real sector limit. */ |
| 367 | blk_queue_max_sectors(vblk->disk->queue, -1U); |
| 368 | |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame] | 369 | /* Host can optionally specify maximum segment size and number of |
| 370 | * segments. */ |
| 371 | err = virtio_config_val(vdev, VIRTIO_BLK_F_SIZE_MAX, |
| 372 | offsetof(struct virtio_blk_config, size_max), |
| 373 | &v); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 374 | if (!err) |
| 375 | blk_queue_max_segment_size(vblk->disk->queue, v); |
Rusty Russell | 4b7f7e2 | 2008-12-30 09:26:04 -0600 | [diff] [blame] | 376 | else |
Randy Dunlap | b194aee | 2008-11-26 13:15:50 -0800 | [diff] [blame] | 377 | blk_queue_max_segment_size(vblk->disk->queue, -1U); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 378 | |
Christian Borntraeger | 066f4d8 | 2008-05-29 11:08:26 +0200 | [diff] [blame] | 379 | /* Host can optionally specify the block size of the device */ |
| 380 | err = virtio_config_val(vdev, VIRTIO_BLK_F_BLK_SIZE, |
| 381 | offsetof(struct virtio_blk_config, blk_size), |
| 382 | &blk_size); |
| 383 | if (!err) |
Martin K. Petersen | e1defc4 | 2009-05-22 17:17:49 -0400 | [diff] [blame] | 384 | blk_queue_logical_block_size(vblk->disk->queue, blk_size); |
Christian Borntraeger | 066f4d8 | 2008-05-29 11:08:26 +0200 | [diff] [blame] | 385 | |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 386 | add_disk(vblk->disk); |
| 387 | return 0; |
| 388 | |
| 389 | out_put_disk: |
| 390 | put_disk(vblk->disk); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 391 | out_mempool: |
| 392 | mempool_destroy(vblk->pool); |
| 393 | out_free_vq: |
Michael S. Tsirkin | d2a7ddd | 2009-06-12 22:16:36 -0600 | [diff] [blame] | 394 | vdev->config->del_vqs(vdev); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 395 | out_free_vblk: |
| 396 | kfree(vblk); |
| 397 | out: |
| 398 | return err; |
| 399 | } |
| 400 | |
Mike Frysinger | 98e9444 | 2009-05-18 03:39:09 -0400 | [diff] [blame] | 401 | static void __devexit virtblk_remove(struct virtio_device *vdev) |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 402 | { |
| 403 | struct virtio_blk *vblk = vdev->priv; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 404 | |
Rusty Russell | 6e5aa7e | 2008-02-04 23:50:03 -0500 | [diff] [blame] | 405 | /* Nothing should be pending. */ |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 406 | BUG_ON(!list_empty(&vblk->reqs)); |
Rusty Russell | 6e5aa7e | 2008-02-04 23:50:03 -0500 | [diff] [blame] | 407 | |
| 408 | /* Stop all the virtqueues. */ |
| 409 | vdev->config->reset(vdev); |
| 410 | |
Chris Lalancette | ac9d463 | 2008-05-30 15:09:41 -0500 | [diff] [blame] | 411 | del_gendisk(vblk->disk); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 412 | blk_cleanup_queue(vblk->disk->queue); |
| 413 | put_disk(vblk->disk); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 414 | mempool_destroy(vblk->pool); |
Michael S. Tsirkin | d2a7ddd | 2009-06-12 22:16:36 -0600 | [diff] [blame] | 415 | vdev->config->del_vqs(vdev); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 416 | kfree(vblk); |
| 417 | } |
| 418 | |
| 419 | static struct virtio_device_id id_table[] = { |
| 420 | { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID }, |
| 421 | { 0 }, |
| 422 | }; |
| 423 | |
Rusty Russell | c45a681 | 2008-05-02 21:50:50 -0500 | [diff] [blame] | 424 | static unsigned int features[] = { |
| 425 | VIRTIO_BLK_F_BARRIER, VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, |
Christian Borntraeger | 066f4d8 | 2008-05-29 11:08:26 +0200 | [diff] [blame] | 426 | VIRTIO_BLK_F_GEOMETRY, VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, |
john cooper | 1d589bb | 2009-06-09 14:41:40 +0200 | [diff] [blame] | 427 | VIRTIO_BLK_F_SCSI, VIRTIO_BLK_F_IDENTIFY |
Rusty Russell | c45a681 | 2008-05-02 21:50:50 -0500 | [diff] [blame] | 428 | }; |
| 429 | |
Rakib Mullick | 4fbfff76 | 2009-07-17 20:13:22 +0600 | [diff] [blame] | 430 | /* |
| 431 | * virtio_blk causes spurious section mismatch warning by |
| 432 | * simultaneously referring to a __devinit and a __devexit function. |
| 433 | * Use __refdata to avoid this warning. |
| 434 | */ |
| 435 | static struct virtio_driver __refdata virtio_blk = { |
Rusty Russell | c45a681 | 2008-05-02 21:50:50 -0500 | [diff] [blame] | 436 | .feature_table = features, |
| 437 | .feature_table_size = ARRAY_SIZE(features), |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 438 | .driver.name = KBUILD_MODNAME, |
| 439 | .driver.owner = THIS_MODULE, |
| 440 | .id_table = id_table, |
| 441 | .probe = virtblk_probe, |
| 442 | .remove = __devexit_p(virtblk_remove), |
| 443 | }; |
| 444 | |
| 445 | static int __init init(void) |
| 446 | { |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 447 | major = register_blkdev(0, "virtblk"); |
| 448 | if (major < 0) |
| 449 | return major; |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 450 | return register_virtio_driver(&virtio_blk); |
| 451 | } |
| 452 | |
| 453 | static void __exit fini(void) |
| 454 | { |
Christian Borntraeger | 4f3bf19 | 2008-01-31 15:53:53 +0100 | [diff] [blame] | 455 | unregister_blkdev(major, "virtblk"); |
Rusty Russell | e467cde | 2007-10-22 11:03:38 +1000 | [diff] [blame] | 456 | unregister_virtio_driver(&virtio_blk); |
| 457 | } |
| 458 | module_init(init); |
| 459 | module_exit(fini); |
| 460 | |
| 461 | MODULE_DEVICE_TABLE(virtio, id_table); |
| 462 | MODULE_DESCRIPTION("Virtio block driver"); |
| 463 | MODULE_LICENSE("GPL"); |