Commit | Line | Data |
---|---|---|
e467cde2 RR |
1 | //#define DEBUG |
2 | #include <linux/spinlock.h> | |
5a0e3ad6 | 3 | #include <linux/slab.h> |
e467cde2 RR |
4 | #include <linux/blkdev.h> |
5 | #include <linux/hdreg.h> | |
0c8d44f2 | 6 | #include <linux/module.h> |
4678d6f9 | 7 | #include <linux/mutex.h> |
ad71473d | 8 | #include <linux/interrupt.h> |
e467cde2 RR |
9 | #include <linux/virtio.h> |
10 | #include <linux/virtio_blk.h> | |
3d1266c7 | 11 | #include <linux/scatterlist.h> |
7a7c924c | 12 | #include <linux/string_helpers.h> |
6917f83f | 13 | #include <scsi/scsi_cmnd.h> |
5087a50e | 14 | #include <linux/idr.h> |
1cf7e9c6 | 15 | #include <linux/blk-mq.h> |
ad71473d | 16 | #include <linux/blk-mq-virtio.h> |
1cf7e9c6 | 17 | #include <linux/numa.h> |
3d1266c7 | 18 | |
4f3bf19c | 19 | #define PART_BITS 4 |
6a27b656 | 20 | #define VQ_NAME_LEN 16 |
e467cde2 | 21 | |
5087a50e MT |
22 | static int major; |
23 | static DEFINE_IDA(vd_index_ida); | |
24 | ||
2a647bfe | 25 | static struct workqueue_struct *virtblk_wq; |
4f3bf19c | 26 | |
6a27b656 ML |
27 | struct virtio_blk_vq { |
28 | struct virtqueue *vq; | |
29 | spinlock_t lock; | |
30 | char name[VQ_NAME_LEN]; | |
31 | } ____cacheline_aligned_in_smp; | |
32 | ||
bb6ec576 | 33 | struct virtio_blk { |
e467cde2 | 34 | struct virtio_device *vdev; |
e467cde2 RR |
35 | |
36 | /* The disk structure for the kernel. */ | |
37 | struct gendisk *disk; | |
38 | ||
24d2f903 CH |
39 | /* Block layer tags. */ |
40 | struct blk_mq_tag_set tag_set; | |
41 | ||
7a7c924c CH |
42 | /* Process context for config space updates */ |
43 | struct work_struct config_work; | |
44 | ||
0864b79a RR |
45 | /* What host tells us, plus 2 for header & tailer. */ |
46 | unsigned int sg_elems; | |
47 | ||
5087a50e MT |
48 | /* Ida index - used to track minor number allocations. */ |
49 | int index; | |
6a27b656 ML |
50 | |
51 | /* num of vqs */ | |
52 | int num_vqs; | |
53 | struct virtio_blk_vq *vqs; | |
e467cde2 RR |
54 | }; |
55 | ||
bb6ec576 | 56 | struct virtblk_req { |
97b50a65 CH |
57 | #ifdef CONFIG_VIRTIO_BLK_SCSI |
58 | struct scsi_request sreq; /* for SCSI passthrough, must be first */ | |
59 | u8 sense[SCSI_SENSE_BUFFERSIZE]; | |
1cde26f9 | 60 | struct virtio_scsi_inhdr in_hdr; |
97b50a65 CH |
61 | #endif |
62 | struct virtio_blk_outhdr out_hdr; | |
cb38fa23 | 63 | u8 status; |
a98755c5 | 64 | struct scatterlist sg[]; |
e467cde2 RR |
65 | }; |
66 | ||
a98755c5 AH |
67 | static inline int virtblk_result(struct virtblk_req *vbr) |
68 | { | |
69 | switch (vbr->status) { | |
70 | case VIRTIO_BLK_S_OK: | |
71 | return 0; | |
72 | case VIRTIO_BLK_S_UNSUPP: | |
73 | return -ENOTTY; | |
74 | default: | |
75 | return -EIO; | |
76 | } | |
77 | } | |
78 | ||
97b50a65 CH |
79 | /* |
80 | * If this is a packet command we need a couple of additional headers. Behind | |
81 | * the normal outhdr we put a segment with the scsi command block, and before | |
82 | * the normal inhdr we put the sense data and the inhdr with additional status | |
83 | * information. | |
84 | */ | |
85 | #ifdef CONFIG_VIRTIO_BLK_SCSI | |
86 | static int virtblk_add_req_scsi(struct virtqueue *vq, struct virtblk_req *vbr, | |
87 | struct scatterlist *data_sg, bool have_data) | |
c85a1f91 | 88 | { |
20af3cfd | 89 | struct scatterlist hdr, status, cmd, sense, inhdr, *sgs[6]; |
8f39db9d PB |
90 | unsigned int num_out = 0, num_in = 0; |
91 | ||
92 | sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr)); | |
93 | sgs[num_out++] = &hdr; | |
97b50a65 CH |
94 | sg_init_one(&cmd, vbr->sreq.cmd, vbr->sreq.cmd_len); |
95 | sgs[num_out++] = &cmd; | |
96 | ||
97 | if (have_data) { | |
98 | if (vbr->out_hdr.type & cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT)) | |
99 | sgs[num_out++] = data_sg; | |
100 | else | |
101 | sgs[num_out + num_in++] = data_sg; | |
102 | } | |
103 | ||
104 | sg_init_one(&sense, vbr->sense, SCSI_SENSE_BUFFERSIZE); | |
105 | sgs[num_out + num_in++] = &sense; | |
106 | sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr)); | |
107 | sgs[num_out + num_in++] = &inhdr; | |
108 | sg_init_one(&status, &vbr->status, sizeof(vbr->status)); | |
109 | sgs[num_out + num_in++] = &status; | |
110 | ||
111 | return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC); | |
112 | } | |
113 | ||
a1a6e62b | 114 | static inline void virtblk_scsi_request_done(struct request *req) |
97b50a65 CH |
115 | { |
116 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); | |
117 | struct virtio_blk *vblk = req->q->queuedata; | |
118 | struct scsi_request *sreq = &vbr->sreq; | |
119 | ||
120 | sreq->resid_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.residual); | |
121 | sreq->sense_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.sense_len); | |
17d5363b | 122 | sreq->result = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.errors); |
97b50a65 CH |
123 | } |
124 | ||
125 | static int virtblk_ioctl(struct block_device *bdev, fmode_t mode, | |
126 | unsigned int cmd, unsigned long data) | |
127 | { | |
128 | struct gendisk *disk = bdev->bd_disk; | |
129 | struct virtio_blk *vblk = disk->private_data; | |
8f39db9d | 130 | |
20af3cfd | 131 | /* |
97b50a65 | 132 | * Only allow the generic SCSI ioctls if the host can support it. |
20af3cfd | 133 | */ |
97b50a65 CH |
134 | if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI)) |
135 | return -ENOTTY; | |
136 | ||
137 | return scsi_cmd_blk_ioctl(bdev, mode, cmd, | |
138 | (void __user *)data); | |
139 | } | |
140 | #else | |
141 | static inline int virtblk_add_req_scsi(struct virtqueue *vq, | |
142 | struct virtblk_req *vbr, struct scatterlist *data_sg, | |
143 | bool have_data) | |
144 | { | |
145 | return -EIO; | |
146 | } | |
a1a6e62b | 147 | static inline void virtblk_scsi_request_done(struct request *req) |
97b50a65 CH |
148 | { |
149 | } | |
150 | #define virtblk_ioctl NULL | |
151 | #endif /* CONFIG_VIRTIO_BLK_SCSI */ | |
152 | ||
153 | static int virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr, | |
154 | struct scatterlist *data_sg, bool have_data) | |
155 | { | |
156 | struct scatterlist hdr, status, *sgs[3]; | |
157 | unsigned int num_out = 0, num_in = 0; | |
158 | ||
159 | sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr)); | |
160 | sgs[num_out++] = &hdr; | |
20af3cfd | 161 | |
0a11cc36 | 162 | if (have_data) { |
19c1c5a6 | 163 | if (vbr->out_hdr.type & cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT)) |
20af3cfd | 164 | sgs[num_out++] = data_sg; |
8f39db9d | 165 | else |
20af3cfd PB |
166 | sgs[num_out + num_in++] = data_sg; |
167 | } | |
168 | ||
8f39db9d PB |
169 | sg_init_one(&status, &vbr->status, sizeof(vbr->status)); |
170 | sgs[num_out + num_in++] = &status; | |
171 | ||
172 | return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC); | |
5ee21a52 PB |
173 | } |
174 | ||
5124c285 | 175 | static inline void virtblk_request_done(struct request *req) |
a98755c5 | 176 | { |
9d74e257 | 177 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); |
a98755c5 | 178 | |
aebf526b CH |
179 | switch (req_op(req)) { |
180 | case REQ_OP_SCSI_IN: | |
181 | case REQ_OP_SCSI_OUT: | |
a1a6e62b | 182 | virtblk_scsi_request_done(req); |
97b50a65 | 183 | break; |
a98755c5 AH |
184 | } |
185 | ||
d19633d5 | 186 | blk_mq_end_request(req, virtblk_result(vbr)); |
a98755c5 AH |
187 | } |
188 | ||
189 | static void virtblk_done(struct virtqueue *vq) | |
e467cde2 RR |
190 | { |
191 | struct virtio_blk *vblk = vq->vdev->priv; | |
1cf7e9c6 | 192 | bool req_done = false; |
6a27b656 | 193 | int qid = vq->index; |
e467cde2 | 194 | struct virtblk_req *vbr; |
e467cde2 | 195 | unsigned long flags; |
a98755c5 | 196 | unsigned int len; |
e467cde2 | 197 | |
6a27b656 | 198 | spin_lock_irqsave(&vblk->vqs[qid].lock, flags); |
bb811108 AH |
199 | do { |
200 | virtqueue_disable_cb(vq); | |
6a27b656 | 201 | while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) { |
85dada09 CH |
202 | struct request *req = blk_mq_rq_from_pdu(vbr); |
203 | ||
d19633d5 | 204 | blk_mq_complete_request(req, 0); |
1cf7e9c6 | 205 | req_done = true; |
33659ebb | 206 | } |
7f03b17d HG |
207 | if (unlikely(virtqueue_is_broken(vq))) |
208 | break; | |
bb811108 | 209 | } while (!virtqueue_enable_cb(vq)); |
1cf7e9c6 | 210 | |
e467cde2 | 211 | /* In case queue is stopped waiting for more buffers. */ |
a98755c5 | 212 | if (req_done) |
1b4a3258 | 213 | blk_mq_start_stopped_hw_queues(vblk->disk->queue, true); |
6a27b656 | 214 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
a98755c5 AH |
215 | } |
216 | ||
74c45052 JA |
217 | static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, |
218 | const struct blk_mq_queue_data *bd) | |
e467cde2 | 219 | { |
1cf7e9c6 | 220 | struct virtio_blk *vblk = hctx->queue->queuedata; |
74c45052 | 221 | struct request *req = bd->rq; |
9d74e257 | 222 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); |
1cf7e9c6 | 223 | unsigned long flags; |
20af3cfd | 224 | unsigned int num; |
6a27b656 | 225 | int qid = hctx->queue_num; |
5261b85e | 226 | int err; |
e8edca6f | 227 | bool notify = false; |
aebf526b | 228 | u32 type; |
e467cde2 | 229 | |
1cf7e9c6 | 230 | BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems); |
e467cde2 | 231 | |
aebf526b CH |
232 | switch (req_op(req)) { |
233 | case REQ_OP_READ: | |
234 | case REQ_OP_WRITE: | |
235 | type = 0; | |
236 | break; | |
237 | case REQ_OP_FLUSH: | |
238 | type = VIRTIO_BLK_T_FLUSH; | |
239 | break; | |
240 | case REQ_OP_SCSI_IN: | |
241 | case REQ_OP_SCSI_OUT: | |
242 | type = VIRTIO_BLK_T_SCSI_CMD; | |
243 | break; | |
244 | case REQ_OP_DRV_IN: | |
245 | type = VIRTIO_BLK_T_GET_ID; | |
246 | break; | |
247 | default: | |
248 | WARN_ON_ONCE(1); | |
249 | return BLK_MQ_RQ_QUEUE_ERROR; | |
e467cde2 RR |
250 | } |
251 | ||
aebf526b CH |
252 | vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, type); |
253 | vbr->out_hdr.sector = type ? | |
254 | 0 : cpu_to_virtio64(vblk->vdev, blk_rq_pos(req)); | |
255 | vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(req)); | |
256 | ||
e2490073 CH |
257 | blk_mq_start_request(req); |
258 | ||
85dada09 | 259 | num = blk_rq_map_sg(hctx->queue, req, vbr->sg); |
1cde26f9 | 260 | if (num) { |
85dada09 | 261 | if (rq_data_dir(req) == WRITE) |
19c1c5a6 | 262 | vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_OUT); |
20af3cfd | 263 | else |
19c1c5a6 | 264 | vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_IN); |
e467cde2 RR |
265 | } |
266 | ||
6a27b656 | 267 | spin_lock_irqsave(&vblk->vqs[qid].lock, flags); |
aebf526b | 268 | if (req_op(req) == REQ_OP_SCSI_IN || req_op(req) == REQ_OP_SCSI_OUT) |
97b50a65 CH |
269 | err = virtblk_add_req_scsi(vblk->vqs[qid].vq, vbr, vbr->sg, num); |
270 | else | |
271 | err = virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num); | |
5261b85e | 272 | if (err) { |
6a27b656 | 273 | virtqueue_kick(vblk->vqs[qid].vq); |
1cf7e9c6 | 274 | blk_mq_stop_hw_queue(hctx); |
6a27b656 | 275 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
5261b85e RR |
276 | /* Out of mem doesn't actually happen, since we fall back |
277 | * to direct descriptors */ | |
278 | if (err == -ENOMEM || err == -ENOSPC) | |
279 | return BLK_MQ_RQ_QUEUE_BUSY; | |
280 | return BLK_MQ_RQ_QUEUE_ERROR; | |
a98755c5 AH |
281 | } |
282 | ||
74c45052 | 283 | if (bd->last && virtqueue_kick_prepare(vblk->vqs[qid].vq)) |
e8edca6f | 284 | notify = true; |
6a27b656 | 285 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
e8edca6f ML |
286 | |
287 | if (notify) | |
6a27b656 | 288 | virtqueue_notify(vblk->vqs[qid].vq); |
1cf7e9c6 | 289 | return BLK_MQ_RQ_QUEUE_OK; |
a98755c5 AH |
290 | } |
291 | ||
4cb2ea28 | 292 | /* return id (s/n) string for *disk to *id_str |
293 | */ | |
294 | static int virtblk_get_id(struct gendisk *disk, char *id_str) | |
295 | { | |
296 | struct virtio_blk *vblk = disk->private_data; | |
f9596695 | 297 | struct request_queue *q = vblk->disk->queue; |
4cb2ea28 | 298 | struct request *req; |
e4c4776d | 299 | int err; |
4cb2ea28 | 300 | |
aebf526b | 301 | req = blk_get_request(q, REQ_OP_DRV_IN, GFP_KERNEL); |
f9596695 | 302 | if (IS_ERR(req)) |
4cb2ea28 | 303 | return PTR_ERR(req); |
f9596695 CH |
304 | |
305 | err = blk_rq_map_kern(q, req, id_str, VIRTIO_BLK_ID_BYTES, GFP_KERNEL); | |
306 | if (err) | |
307 | goto out; | |
308 | ||
b7819b92 | 309 | blk_execute_rq(vblk->disk->queue, vblk->disk, req, false); |
d19633d5 | 310 | err = virtblk_result(blk_mq_rq_to_pdu(req)); |
f9596695 | 311 | out: |
e4c4776d | 312 | blk_put_request(req); |
e4c4776d | 313 | return err; |
4cb2ea28 | 314 | } |
315 | ||
135da0b0 CB |
316 | /* We provide getgeo only to please some old bootloader/partitioning tools */ |
317 | static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo) | |
318 | { | |
48e4043d | 319 | struct virtio_blk *vblk = bd->bd_disk->private_data; |
48e4043d RH |
320 | |
321 | /* see if the host passed in geometry config */ | |
855e0c52 RR |
322 | if (virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_GEOMETRY)) { |
323 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
324 | geometry.cylinders, &geo->cylinders); | |
325 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
326 | geometry.heads, &geo->heads); | |
327 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
328 | geometry.sectors, &geo->sectors); | |
48e4043d RH |
329 | } else { |
330 | /* some standard values, similar to sd */ | |
331 | geo->heads = 1 << 6; | |
332 | geo->sectors = 1 << 5; | |
333 | geo->cylinders = get_capacity(bd->bd_disk) >> 11; | |
334 | } | |
135da0b0 CB |
335 | return 0; |
336 | } | |
337 | ||
83d5cde4 | 338 | static const struct block_device_operations virtblk_fops = { |
8a6cfeb6 | 339 | .ioctl = virtblk_ioctl, |
135da0b0 CB |
340 | .owner = THIS_MODULE, |
341 | .getgeo = virtblk_getgeo, | |
e467cde2 RR |
342 | }; |
343 | ||
d50ed907 CB |
344 | static int index_to_minor(int index) |
345 | { | |
346 | return index << PART_BITS; | |
347 | } | |
348 | ||
5087a50e MT |
349 | static int minor_to_index(int minor) |
350 | { | |
351 | return minor >> PART_BITS; | |
352 | } | |
353 | ||
a5eb9e4f RH |
354 | static ssize_t virtblk_serial_show(struct device *dev, |
355 | struct device_attribute *attr, char *buf) | |
356 | { | |
357 | struct gendisk *disk = dev_to_disk(dev); | |
358 | int err; | |
359 | ||
360 | /* sysfs gives us a PAGE_SIZE buffer */ | |
361 | BUILD_BUG_ON(PAGE_SIZE < VIRTIO_BLK_ID_BYTES); | |
362 | ||
363 | buf[VIRTIO_BLK_ID_BYTES] = '\0'; | |
364 | err = virtblk_get_id(disk, buf); | |
365 | if (!err) | |
366 | return strlen(buf); | |
367 | ||
368 | if (err == -EIO) /* Unsupported? Make it empty. */ | |
369 | return 0; | |
370 | ||
371 | return err; | |
372 | } | |
393c525b MT |
373 | |
374 | static DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL); | |
a5eb9e4f | 375 | |
7a7c924c CH |
376 | static void virtblk_config_changed_work(struct work_struct *work) |
377 | { | |
378 | struct virtio_blk *vblk = | |
379 | container_of(work, struct virtio_blk, config_work); | |
380 | struct virtio_device *vdev = vblk->vdev; | |
381 | struct request_queue *q = vblk->disk->queue; | |
382 | char cap_str_2[10], cap_str_10[10]; | |
9d9598b8 | 383 | char *envp[] = { "RESIZE=1", NULL }; |
b9f28d86 | 384 | u64 capacity; |
7a7c924c CH |
385 | |
386 | /* Host must always specify the capacity. */ | |
855e0c52 | 387 | virtio_cread(vdev, struct virtio_blk_config, capacity, &capacity); |
7a7c924c CH |
388 | |
389 | /* If capacity is too big, truncate with warning. */ | |
390 | if ((sector_t)capacity != capacity) { | |
391 | dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n", | |
392 | (unsigned long long)capacity); | |
393 | capacity = (sector_t)-1; | |
394 | } | |
395 | ||
b9f28d86 JB |
396 | string_get_size(capacity, queue_logical_block_size(q), |
397 | STRING_UNITS_2, cap_str_2, sizeof(cap_str_2)); | |
398 | string_get_size(capacity, queue_logical_block_size(q), | |
399 | STRING_UNITS_10, cap_str_10, sizeof(cap_str_10)); | |
7a7c924c CH |
400 | |
401 | dev_notice(&vdev->dev, | |
402 | "new size: %llu %d-byte logical blocks (%s/%s)\n", | |
403 | (unsigned long long)capacity, | |
404 | queue_logical_block_size(q), | |
405 | cap_str_10, cap_str_2); | |
406 | ||
407 | set_capacity(vblk->disk, capacity); | |
e9986f30 | 408 | revalidate_disk(vblk->disk); |
9d9598b8 | 409 | kobject_uevent_env(&disk_to_dev(vblk->disk)->kobj, KOBJ_CHANGE, envp); |
7a7c924c CH |
410 | } |
411 | ||
412 | static void virtblk_config_changed(struct virtio_device *vdev) | |
413 | { | |
414 | struct virtio_blk *vblk = vdev->priv; | |
415 | ||
416 | queue_work(virtblk_wq, &vblk->config_work); | |
417 | } | |
418 | ||
6abd6e5a AS |
419 | static int init_vq(struct virtio_blk *vblk) |
420 | { | |
2ff98449 | 421 | int err; |
6a27b656 ML |
422 | int i; |
423 | vq_callback_t **callbacks; | |
424 | const char **names; | |
425 | struct virtqueue **vqs; | |
426 | unsigned short num_vqs; | |
427 | struct virtio_device *vdev = vblk->vdev; | |
ad71473d | 428 | struct irq_affinity desc = { 0, }; |
6a27b656 ML |
429 | |
430 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ, | |
431 | struct virtio_blk_config, num_queues, | |
432 | &num_vqs); | |
433 | if (err) | |
434 | num_vqs = 1; | |
435 | ||
668866b6 | 436 | vblk->vqs = kmalloc_array(num_vqs, sizeof(*vblk->vqs), GFP_KERNEL); |
347a5293 MH |
437 | if (!vblk->vqs) |
438 | return -ENOMEM; | |
6a27b656 | 439 | |
668866b6 ME |
440 | names = kmalloc_array(num_vqs, sizeof(*names), GFP_KERNEL); |
441 | callbacks = kmalloc_array(num_vqs, sizeof(*callbacks), GFP_KERNEL); | |
442 | vqs = kmalloc_array(num_vqs, sizeof(*vqs), GFP_KERNEL); | |
347a5293 MH |
443 | if (!names || !callbacks || !vqs) { |
444 | err = -ENOMEM; | |
445 | goto out; | |
446 | } | |
6abd6e5a | 447 | |
6a27b656 ML |
448 | for (i = 0; i < num_vqs; i++) { |
449 | callbacks[i] = virtblk_done; | |
450 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req.%d", i); | |
451 | names[i] = vblk->vqs[i].name; | |
452 | } | |
453 | ||
454 | /* Discover virtqueues and write information to configuration. */ | |
fb5e31d9 | 455 | err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names, |
ad71473d | 456 | &desc); |
6a27b656 | 457 | if (err) |
347a5293 | 458 | goto out; |
6abd6e5a | 459 | |
6a27b656 ML |
460 | for (i = 0; i < num_vqs; i++) { |
461 | spin_lock_init(&vblk->vqs[i].lock); | |
462 | vblk->vqs[i].vq = vqs[i]; | |
463 | } | |
464 | vblk->num_vqs = num_vqs; | |
465 | ||
347a5293 | 466 | out: |
6a27b656 | 467 | kfree(vqs); |
6a27b656 | 468 | kfree(callbacks); |
6a27b656 | 469 | kfree(names); |
6a27b656 ML |
470 | if (err) |
471 | kfree(vblk->vqs); | |
6abd6e5a AS |
472 | return err; |
473 | } | |
474 | ||
c0aa3e09 RM |
475 | /* |
476 | * Legacy naming scheme used for virtio devices. We are stuck with it for | |
477 | * virtio blk but don't ever use it for any new driver. | |
478 | */ | |
479 | static int virtblk_name_format(char *prefix, int index, char *buf, int buflen) | |
480 | { | |
481 | const int base = 'z' - 'a' + 1; | |
482 | char *begin = buf + strlen(prefix); | |
483 | char *end = buf + buflen; | |
484 | char *p; | |
485 | int unit; | |
486 | ||
487 | p = end - 1; | |
488 | *p = '\0'; | |
489 | unit = base; | |
490 | do { | |
491 | if (p == begin) | |
492 | return -EINVAL; | |
493 | *--p = 'a' + (index % unit); | |
494 | index = (index / unit) - 1; | |
495 | } while (index >= 0); | |
496 | ||
497 | memmove(begin, p, end - p); | |
498 | memcpy(buf, prefix, strlen(prefix)); | |
499 | ||
500 | return 0; | |
501 | } | |
502 | ||
cd5d5038 PB |
503 | static int virtblk_get_cache_mode(struct virtio_device *vdev) |
504 | { | |
505 | u8 writeback; | |
506 | int err; | |
507 | ||
855e0c52 RR |
508 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE, |
509 | struct virtio_blk_config, wce, | |
510 | &writeback); | |
592002f5 MT |
511 | |
512 | /* | |
513 | * If WCE is not configurable and flush is not available, | |
514 | * assume no writeback cache is in use. | |
515 | */ | |
cd5d5038 | 516 | if (err) |
592002f5 | 517 | writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH); |
cd5d5038 PB |
518 | |
519 | return writeback; | |
520 | } | |
521 | ||
522 | static void virtblk_update_cache_mode(struct virtio_device *vdev) | |
523 | { | |
524 | u8 writeback = virtblk_get_cache_mode(vdev); | |
525 | struct virtio_blk *vblk = vdev->priv; | |
526 | ||
ad9126ac | 527 | blk_queue_write_cache(vblk->disk->queue, writeback, false); |
cd5d5038 PB |
528 | revalidate_disk(vblk->disk); |
529 | } | |
530 | ||
531 | static const char *const virtblk_cache_types[] = { | |
532 | "write through", "write back" | |
533 | }; | |
534 | ||
535 | static ssize_t | |
536 | virtblk_cache_type_store(struct device *dev, struct device_attribute *attr, | |
537 | const char *buf, size_t count) | |
538 | { | |
539 | struct gendisk *disk = dev_to_disk(dev); | |
540 | struct virtio_blk *vblk = disk->private_data; | |
541 | struct virtio_device *vdev = vblk->vdev; | |
542 | int i; | |
cd5d5038 PB |
543 | |
544 | BUG_ON(!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_CONFIG_WCE)); | |
545 | for (i = ARRAY_SIZE(virtblk_cache_types); --i >= 0; ) | |
546 | if (sysfs_streq(buf, virtblk_cache_types[i])) | |
547 | break; | |
548 | ||
549 | if (i < 0) | |
550 | return -EINVAL; | |
551 | ||
855e0c52 | 552 | virtio_cwrite8(vdev, offsetof(struct virtio_blk_config, wce), i); |
cd5d5038 PB |
553 | virtblk_update_cache_mode(vdev); |
554 | return count; | |
555 | } | |
556 | ||
557 | static ssize_t | |
558 | virtblk_cache_type_show(struct device *dev, struct device_attribute *attr, | |
559 | char *buf) | |
560 | { | |
561 | struct gendisk *disk = dev_to_disk(dev); | |
562 | struct virtio_blk *vblk = disk->private_data; | |
563 | u8 writeback = virtblk_get_cache_mode(vblk->vdev); | |
564 | ||
565 | BUG_ON(writeback >= ARRAY_SIZE(virtblk_cache_types)); | |
566 | return snprintf(buf, 40, "%s\n", virtblk_cache_types[writeback]); | |
567 | } | |
568 | ||
569 | static const struct device_attribute dev_attr_cache_type_ro = | |
570 | __ATTR(cache_type, S_IRUGO, | |
571 | virtblk_cache_type_show, NULL); | |
572 | static const struct device_attribute dev_attr_cache_type_rw = | |
573 | __ATTR(cache_type, S_IRUGO|S_IWUSR, | |
574 | virtblk_cache_type_show, virtblk_cache_type_store); | |
575 | ||
24d2f903 CH |
576 | static int virtblk_init_request(void *data, struct request *rq, |
577 | unsigned int hctx_idx, unsigned int request_idx, | |
578 | unsigned int numa_node) | |
e9b267d9 CH |
579 | { |
580 | struct virtio_blk *vblk = data; | |
581 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(rq); | |
582 | ||
97b50a65 | 583 | #ifdef CONFIG_VIRTIO_BLK_SCSI |
82ed4db4 | 584 | vbr->sreq.sense = vbr->sense; |
97b50a65 | 585 | #endif |
e9b267d9 CH |
586 | sg_init_table(vbr->sg, vblk->sg_elems); |
587 | return 0; | |
588 | } | |
589 | ||
ad71473d CH |
590 | static int virtblk_map_queues(struct blk_mq_tag_set *set) |
591 | { | |
592 | struct virtio_blk *vblk = set->driver_data; | |
593 | ||
594 | return blk_mq_virtio_map_queues(set, vblk->vdev, 0); | |
595 | } | |
596 | ||
f363b089 | 597 | static const struct blk_mq_ops virtio_mq_ops = { |
1cf7e9c6 | 598 | .queue_rq = virtio_queue_rq, |
5124c285 | 599 | .complete = virtblk_request_done, |
24d2f903 | 600 | .init_request = virtblk_init_request, |
ad71473d | 601 | .map_queues = virtblk_map_queues, |
1cf7e9c6 JA |
602 | }; |
603 | ||
24d2f903 CH |
604 | static unsigned int virtblk_queue_depth; |
605 | module_param_named(queue_depth, virtblk_queue_depth, uint, 0444); | |
1cf7e9c6 | 606 | |
8d85fce7 | 607 | static int virtblk_probe(struct virtio_device *vdev) |
e467cde2 RR |
608 | { |
609 | struct virtio_blk *vblk; | |
69740c8b | 610 | struct request_queue *q; |
5087a50e | 611 | int err, index; |
a98755c5 | 612 | |
e467cde2 | 613 | u64 cap; |
69740c8b CH |
614 | u32 v, blk_size, sg_elems, opt_io_size; |
615 | u16 min_io_size; | |
616 | u8 physical_block_exp, alignment_offset; | |
e467cde2 | 617 | |
a4379fd8 MT |
618 | if (!vdev->config->get) { |
619 | dev_err(&vdev->dev, "%s failure: config access disabled\n", | |
620 | __func__); | |
621 | return -EINVAL; | |
622 | } | |
623 | ||
5087a50e MT |
624 | err = ida_simple_get(&vd_index_ida, 0, minor_to_index(1 << MINORBITS), |
625 | GFP_KERNEL); | |
626 | if (err < 0) | |
627 | goto out; | |
628 | index = err; | |
4f3bf19c | 629 | |
0864b79a | 630 | /* We need to know how many segments before we allocate. */ |
855e0c52 RR |
631 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SEG_MAX, |
632 | struct virtio_blk_config, seg_max, | |
633 | &sg_elems); | |
a5b365a6 CH |
634 | |
635 | /* We need at least one SG element, whatever they say. */ | |
636 | if (err || !sg_elems) | |
0864b79a RR |
637 | sg_elems = 1; |
638 | ||
639 | /* We need an extra sg elements at head and tail. */ | |
640 | sg_elems += 2; | |
1cf7e9c6 | 641 | vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL); |
e467cde2 RR |
642 | if (!vblk) { |
643 | err = -ENOMEM; | |
5087a50e | 644 | goto out_free_index; |
e467cde2 RR |
645 | } |
646 | ||
e467cde2 | 647 | vblk->vdev = vdev; |
0864b79a | 648 | vblk->sg_elems = sg_elems; |
a98755c5 | 649 | |
7a7c924c | 650 | INIT_WORK(&vblk->config_work, virtblk_config_changed_work); |
e467cde2 | 651 | |
6abd6e5a AS |
652 | err = init_vq(vblk); |
653 | if (err) | |
e467cde2 | 654 | goto out_free_vblk; |
e467cde2 | 655 | |
e467cde2 | 656 | /* FIXME: How many partitions? How long is a piece of string? */ |
4f3bf19c | 657 | vblk->disk = alloc_disk(1 << PART_BITS); |
e467cde2 RR |
658 | if (!vblk->disk) { |
659 | err = -ENOMEM; | |
1cf7e9c6 | 660 | goto out_free_vq; |
e467cde2 RR |
661 | } |
662 | ||
fc4324b4 | 663 | /* Default queue sizing is to fill the ring. */ |
24d2f903 | 664 | if (!virtblk_queue_depth) { |
6a27b656 | 665 | virtblk_queue_depth = vblk->vqs[0].vq->num_free; |
fc4324b4 RR |
666 | /* ... but without indirect descs, we use 2 descs per req */ |
667 | if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC)) | |
24d2f903 | 668 | virtblk_queue_depth /= 2; |
fc4324b4 | 669 | } |
24d2f903 CH |
670 | |
671 | memset(&vblk->tag_set, 0, sizeof(vblk->tag_set)); | |
672 | vblk->tag_set.ops = &virtio_mq_ops; | |
24d2f903 CH |
673 | vblk->tag_set.queue_depth = virtblk_queue_depth; |
674 | vblk->tag_set.numa_node = NUMA_NO_NODE; | |
675 | vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; | |
676 | vblk->tag_set.cmd_size = | |
1cf7e9c6 JA |
677 | sizeof(struct virtblk_req) + |
678 | sizeof(struct scatterlist) * sg_elems; | |
24d2f903 | 679 | vblk->tag_set.driver_data = vblk; |
6a27b656 | 680 | vblk->tag_set.nr_hw_queues = vblk->num_vqs; |
1cf7e9c6 | 681 | |
24d2f903 CH |
682 | err = blk_mq_alloc_tag_set(&vblk->tag_set); |
683 | if (err) | |
684 | goto out_put_disk; | |
685 | ||
6bf6b0aa | 686 | q = blk_mq_init_queue(&vblk->tag_set); |
35b489d3 | 687 | if (IS_ERR(q)) { |
e467cde2 | 688 | err = -ENOMEM; |
24d2f903 | 689 | goto out_free_tags; |
e467cde2 | 690 | } |
6bf6b0aa | 691 | vblk->disk->queue = q; |
e467cde2 | 692 | |
69740c8b | 693 | q->queuedata = vblk; |
7d116b62 | 694 | |
c0aa3e09 | 695 | virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN); |
d50ed907 | 696 | |
e467cde2 | 697 | vblk->disk->major = major; |
d50ed907 | 698 | vblk->disk->first_minor = index_to_minor(index); |
e467cde2 RR |
699 | vblk->disk->private_data = vblk; |
700 | vblk->disk->fops = &virtblk_fops; | |
5fa3142d | 701 | vblk->disk->flags |= GENHD_FL_EXT_DEVT; |
5087a50e | 702 | vblk->index = index; |
4f3bf19c | 703 | |
02c42b7a | 704 | /* configure queue flush support */ |
cd5d5038 | 705 | virtblk_update_cache_mode(vdev); |
e467cde2 | 706 | |
3ef53609 CB |
707 | /* If disk is read-only in the host, the guest should obey */ |
708 | if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO)) | |
709 | set_disk_ro(vblk->disk, 1); | |
710 | ||
a586d4f6 | 711 | /* Host must always specify the capacity. */ |
855e0c52 | 712 | virtio_cread(vdev, struct virtio_blk_config, capacity, &cap); |
e467cde2 RR |
713 | |
714 | /* If capacity is too big, truncate with warning. */ | |
715 | if ((sector_t)cap != cap) { | |
716 | dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n", | |
717 | (unsigned long long)cap); | |
718 | cap = (sector_t)-1; | |
719 | } | |
720 | set_capacity(vblk->disk, cap); | |
721 | ||
0864b79a | 722 | /* We can handle whatever the host told us to handle. */ |
ee714f2d | 723 | blk_queue_max_segments(q, vblk->sg_elems-2); |
0864b79a | 724 | |
4eff3cae | 725 | /* No need to bounce any requests */ |
69740c8b | 726 | blk_queue_bounce_limit(q, BLK_BOUNCE_ANY); |
4eff3cae | 727 | |
4b7f7e20 | 728 | /* No real sector limit. */ |
ee714f2d | 729 | blk_queue_max_hw_sectors(q, -1U); |
4b7f7e20 | 730 | |
a586d4f6 RR |
731 | /* Host can optionally specify maximum segment size and number of |
732 | * segments. */ | |
855e0c52 RR |
733 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SIZE_MAX, |
734 | struct virtio_blk_config, size_max, &v); | |
e467cde2 | 735 | if (!err) |
69740c8b | 736 | blk_queue_max_segment_size(q, v); |
4b7f7e20 | 737 | else |
69740c8b | 738 | blk_queue_max_segment_size(q, -1U); |
e467cde2 | 739 | |
066f4d82 | 740 | /* Host can optionally specify the block size of the device */ |
855e0c52 RR |
741 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE, |
742 | struct virtio_blk_config, blk_size, | |
743 | &blk_size); | |
066f4d82 | 744 | if (!err) |
69740c8b CH |
745 | blk_queue_logical_block_size(q, blk_size); |
746 | else | |
747 | blk_size = queue_logical_block_size(q); | |
748 | ||
749 | /* Use topology information if available */ | |
855e0c52 RR |
750 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
751 | struct virtio_blk_config, physical_block_exp, | |
752 | &physical_block_exp); | |
69740c8b CH |
753 | if (!err && physical_block_exp) |
754 | blk_queue_physical_block_size(q, | |
755 | blk_size * (1 << physical_block_exp)); | |
756 | ||
855e0c52 RR |
757 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
758 | struct virtio_blk_config, alignment_offset, | |
759 | &alignment_offset); | |
69740c8b CH |
760 | if (!err && alignment_offset) |
761 | blk_queue_alignment_offset(q, blk_size * alignment_offset); | |
762 | ||
855e0c52 RR |
763 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
764 | struct virtio_blk_config, min_io_size, | |
765 | &min_io_size); | |
69740c8b CH |
766 | if (!err && min_io_size) |
767 | blk_queue_io_min(q, blk_size * min_io_size); | |
768 | ||
855e0c52 RR |
769 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
770 | struct virtio_blk_config, opt_io_size, | |
771 | &opt_io_size); | |
69740c8b CH |
772 | if (!err && opt_io_size) |
773 | blk_queue_io_opt(q, blk_size * opt_io_size); | |
774 | ||
7a11370e MT |
775 | virtio_device_ready(vdev); |
776 | ||
0d52c756 | 777 | device_add_disk(&vdev->dev, vblk->disk); |
a5eb9e4f RH |
778 | err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial); |
779 | if (err) | |
780 | goto out_del_disk; | |
781 | ||
cd5d5038 PB |
782 | if (virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) |
783 | err = device_create_file(disk_to_dev(vblk->disk), | |
784 | &dev_attr_cache_type_rw); | |
785 | else | |
786 | err = device_create_file(disk_to_dev(vblk->disk), | |
787 | &dev_attr_cache_type_ro); | |
788 | if (err) | |
789 | goto out_del_disk; | |
e467cde2 RR |
790 | return 0; |
791 | ||
a5eb9e4f RH |
792 | out_del_disk: |
793 | del_gendisk(vblk->disk); | |
794 | blk_cleanup_queue(vblk->disk->queue); | |
24d2f903 CH |
795 | out_free_tags: |
796 | blk_mq_free_tag_set(&vblk->tag_set); | |
e467cde2 RR |
797 | out_put_disk: |
798 | put_disk(vblk->disk); | |
e467cde2 | 799 | out_free_vq: |
d2a7ddda | 800 | vdev->config->del_vqs(vdev); |
e467cde2 RR |
801 | out_free_vblk: |
802 | kfree(vblk); | |
5087a50e MT |
803 | out_free_index: |
804 | ida_simple_remove(&vd_index_ida, index); | |
e467cde2 RR |
805 | out: |
806 | return err; | |
807 | } | |
808 | ||
8d85fce7 | 809 | static void virtblk_remove(struct virtio_device *vdev) |
e467cde2 RR |
810 | { |
811 | struct virtio_blk *vblk = vdev->priv; | |
5087a50e | 812 | int index = vblk->index; |
f4953fe6 | 813 | int refc; |
e467cde2 | 814 | |
cc74f719 MT |
815 | /* Make sure no work handler is accessing the device. */ |
816 | flush_work(&vblk->config_work); | |
7a7c924c | 817 | |
02e2b124 | 818 | del_gendisk(vblk->disk); |
483001c7 | 819 | blk_cleanup_queue(vblk->disk->queue); |
02e2b124 | 820 | |
24d2f903 CH |
821 | blk_mq_free_tag_set(&vblk->tag_set); |
822 | ||
6e5aa7ef RR |
823 | /* Stop all the virtqueues. */ |
824 | vdev->config->reset(vdev); | |
825 | ||
2c935bc5 | 826 | refc = kref_read(&disk_to_dev(vblk->disk)->kobj.kref); |
e467cde2 | 827 | put_disk(vblk->disk); |
d2a7ddda | 828 | vdev->config->del_vqs(vdev); |
6a27b656 | 829 | kfree(vblk->vqs); |
e467cde2 | 830 | kfree(vblk); |
f4953fe6 AG |
831 | |
832 | /* Only free device id if we don't have any users */ | |
833 | if (refc == 1) | |
834 | ida_simple_remove(&vd_index_ida, index); | |
e467cde2 RR |
835 | } |
836 | ||
89107000 | 837 | #ifdef CONFIG_PM_SLEEP |
f8fb5bc2 AS |
838 | static int virtblk_freeze(struct virtio_device *vdev) |
839 | { | |
840 | struct virtio_blk *vblk = vdev->priv; | |
841 | ||
842 | /* Ensure we don't receive any more interrupts */ | |
843 | vdev->config->reset(vdev); | |
844 | ||
cc74f719 | 845 | /* Make sure no work handler is accessing the device. */ |
f8fb5bc2 AS |
846 | flush_work(&vblk->config_work); |
847 | ||
1cf7e9c6 | 848 | blk_mq_stop_hw_queues(vblk->disk->queue); |
f8fb5bc2 AS |
849 | |
850 | vdev->config->del_vqs(vdev); | |
851 | return 0; | |
852 | } | |
853 | ||
854 | static int virtblk_restore(struct virtio_device *vdev) | |
855 | { | |
856 | struct virtio_blk *vblk = vdev->priv; | |
857 | int ret; | |
858 | ||
f8fb5bc2 | 859 | ret = init_vq(vdev->priv); |
6d62c37f MT |
860 | if (ret) |
861 | return ret; | |
862 | ||
863 | virtio_device_ready(vdev); | |
1cf7e9c6 | 864 | |
6d62c37f MT |
865 | blk_mq_start_stopped_hw_queues(vblk->disk->queue, true); |
866 | return 0; | |
f8fb5bc2 AS |
867 | } |
868 | #endif | |
869 | ||
47483e25 | 870 | static const struct virtio_device_id id_table[] = { |
e467cde2 RR |
871 | { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID }, |
872 | { 0 }, | |
873 | }; | |
874 | ||
19c1c5a6 | 875 | static unsigned int features_legacy[] = { |
02c42b7a | 876 | VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY, |
97b50a65 CH |
877 | VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, |
878 | #ifdef CONFIG_VIRTIO_BLK_SCSI | |
879 | VIRTIO_BLK_F_SCSI, | |
880 | #endif | |
592002f5 | 881 | VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE, |
6a27b656 | 882 | VIRTIO_BLK_F_MQ, |
19c1c5a6 MT |
883 | } |
884 | ; | |
885 | static unsigned int features[] = { | |
886 | VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY, | |
887 | VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, | |
592002f5 | 888 | VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE, |
19c1c5a6 | 889 | VIRTIO_BLK_F_MQ, |
c45a6816 RR |
890 | }; |
891 | ||
8d85fce7 | 892 | static struct virtio_driver virtio_blk = { |
19c1c5a6 MT |
893 | .feature_table = features, |
894 | .feature_table_size = ARRAY_SIZE(features), | |
895 | .feature_table_legacy = features_legacy, | |
896 | .feature_table_size_legacy = ARRAY_SIZE(features_legacy), | |
897 | .driver.name = KBUILD_MODNAME, | |
898 | .driver.owner = THIS_MODULE, | |
899 | .id_table = id_table, | |
900 | .probe = virtblk_probe, | |
901 | .remove = virtblk_remove, | |
902 | .config_changed = virtblk_config_changed, | |
89107000 | 903 | #ifdef CONFIG_PM_SLEEP |
19c1c5a6 MT |
904 | .freeze = virtblk_freeze, |
905 | .restore = virtblk_restore, | |
f8fb5bc2 | 906 | #endif |
e467cde2 RR |
907 | }; |
908 | ||
909 | static int __init init(void) | |
910 | { | |
7a7c924c CH |
911 | int error; |
912 | ||
913 | virtblk_wq = alloc_workqueue("virtio-blk", 0, 0); | |
914 | if (!virtblk_wq) | |
915 | return -ENOMEM; | |
916 | ||
4f3bf19c | 917 | major = register_blkdev(0, "virtblk"); |
7a7c924c CH |
918 | if (major < 0) { |
919 | error = major; | |
920 | goto out_destroy_workqueue; | |
921 | } | |
922 | ||
923 | error = register_virtio_driver(&virtio_blk); | |
924 | if (error) | |
925 | goto out_unregister_blkdev; | |
926 | return 0; | |
927 | ||
928 | out_unregister_blkdev: | |
929 | unregister_blkdev(major, "virtblk"); | |
930 | out_destroy_workqueue: | |
931 | destroy_workqueue(virtblk_wq); | |
932 | return error; | |
e467cde2 RR |
933 | } |
934 | ||
935 | static void __exit fini(void) | |
936 | { | |
937 | unregister_virtio_driver(&virtio_blk); | |
38f37b57 | 938 | unregister_blkdev(major, "virtblk"); |
7a7c924c | 939 | destroy_workqueue(virtblk_wq); |
e467cde2 RR |
940 | } |
941 | module_init(init); | |
942 | module_exit(fini); | |
943 | ||
944 | MODULE_DEVICE_TABLE(virtio, id_table); | |
945 | MODULE_DESCRIPTION("Virtio block driver"); | |
946 | MODULE_LICENSE("GPL"); |