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Commit | Line | Data |
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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 | ||
114 | static inline void virtblk_scsi_reques_done(struct request *req) | |
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); | |
122 | req->errors = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.errors); | |
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 | } | |
147 | static inline void virtblk_scsi_reques_done(struct request *req) | |
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 AH |
178 | int error = virtblk_result(vbr); |
179 | ||
aebf526b CH |
180 | switch (req_op(req)) { |
181 | case REQ_OP_SCSI_IN: | |
182 | case REQ_OP_SCSI_OUT: | |
97b50a65 CH |
183 | virtblk_scsi_reques_done(req); |
184 | break; | |
aebf526b | 185 | case REQ_OP_DRV_IN: |
a98755c5 | 186 | req->errors = (error != 0); |
97b50a65 | 187 | break; |
a98755c5 AH |
188 | } |
189 | ||
c8a446ad | 190 | blk_mq_end_request(req, error); |
a98755c5 AH |
191 | } |
192 | ||
193 | static void virtblk_done(struct virtqueue *vq) | |
e467cde2 RR |
194 | { |
195 | struct virtio_blk *vblk = vq->vdev->priv; | |
1cf7e9c6 | 196 | bool req_done = false; |
6a27b656 | 197 | int qid = vq->index; |
e467cde2 | 198 | struct virtblk_req *vbr; |
e467cde2 | 199 | unsigned long flags; |
a98755c5 | 200 | unsigned int len; |
e467cde2 | 201 | |
6a27b656 | 202 | spin_lock_irqsave(&vblk->vqs[qid].lock, flags); |
bb811108 AH |
203 | do { |
204 | virtqueue_disable_cb(vq); | |
6a27b656 | 205 | while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) { |
85dada09 CH |
206 | struct request *req = blk_mq_rq_from_pdu(vbr); |
207 | ||
208 | blk_mq_complete_request(req, req->errors); | |
1cf7e9c6 | 209 | req_done = true; |
33659ebb | 210 | } |
7f03b17d HG |
211 | if (unlikely(virtqueue_is_broken(vq))) |
212 | break; | |
bb811108 | 213 | } while (!virtqueue_enable_cb(vq)); |
1cf7e9c6 | 214 | |
e467cde2 | 215 | /* In case queue is stopped waiting for more buffers. */ |
a98755c5 | 216 | if (req_done) |
1b4a3258 | 217 | blk_mq_start_stopped_hw_queues(vblk->disk->queue, true); |
6a27b656 | 218 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
a98755c5 AH |
219 | } |
220 | ||
74c45052 JA |
221 | static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, |
222 | const struct blk_mq_queue_data *bd) | |
e467cde2 | 223 | { |
1cf7e9c6 | 224 | struct virtio_blk *vblk = hctx->queue->queuedata; |
74c45052 | 225 | struct request *req = bd->rq; |
9d74e257 | 226 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); |
1cf7e9c6 | 227 | unsigned long flags; |
20af3cfd | 228 | unsigned int num; |
6a27b656 | 229 | int qid = hctx->queue_num; |
5261b85e | 230 | int err; |
e8edca6f | 231 | bool notify = false; |
aebf526b | 232 | u32 type; |
e467cde2 | 233 | |
1cf7e9c6 | 234 | BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems); |
e467cde2 | 235 | |
aebf526b CH |
236 | switch (req_op(req)) { |
237 | case REQ_OP_READ: | |
238 | case REQ_OP_WRITE: | |
239 | type = 0; | |
240 | break; | |
241 | case REQ_OP_FLUSH: | |
242 | type = VIRTIO_BLK_T_FLUSH; | |
243 | break; | |
244 | case REQ_OP_SCSI_IN: | |
245 | case REQ_OP_SCSI_OUT: | |
246 | type = VIRTIO_BLK_T_SCSI_CMD; | |
247 | break; | |
248 | case REQ_OP_DRV_IN: | |
249 | type = VIRTIO_BLK_T_GET_ID; | |
250 | break; | |
251 | default: | |
252 | WARN_ON_ONCE(1); | |
253 | return BLK_MQ_RQ_QUEUE_ERROR; | |
e467cde2 RR |
254 | } |
255 | ||
aebf526b CH |
256 | vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, type); |
257 | vbr->out_hdr.sector = type ? | |
258 | 0 : cpu_to_virtio64(vblk->vdev, blk_rq_pos(req)); | |
259 | vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(req)); | |
260 | ||
e2490073 CH |
261 | blk_mq_start_request(req); |
262 | ||
85dada09 | 263 | num = blk_rq_map_sg(hctx->queue, req, vbr->sg); |
1cde26f9 | 264 | if (num) { |
85dada09 | 265 | if (rq_data_dir(req) == WRITE) |
19c1c5a6 | 266 | vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_OUT); |
20af3cfd | 267 | else |
19c1c5a6 | 268 | vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_IN); |
e467cde2 RR |
269 | } |
270 | ||
6a27b656 | 271 | spin_lock_irqsave(&vblk->vqs[qid].lock, flags); |
aebf526b | 272 | if (req_op(req) == REQ_OP_SCSI_IN || req_op(req) == REQ_OP_SCSI_OUT) |
97b50a65 CH |
273 | err = virtblk_add_req_scsi(vblk->vqs[qid].vq, vbr, vbr->sg, num); |
274 | else | |
275 | err = virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num); | |
5261b85e | 276 | if (err) { |
6a27b656 | 277 | virtqueue_kick(vblk->vqs[qid].vq); |
1cf7e9c6 | 278 | blk_mq_stop_hw_queue(hctx); |
6a27b656 | 279 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
5261b85e RR |
280 | /* Out of mem doesn't actually happen, since we fall back |
281 | * to direct descriptors */ | |
282 | if (err == -ENOMEM || err == -ENOSPC) | |
283 | return BLK_MQ_RQ_QUEUE_BUSY; | |
284 | return BLK_MQ_RQ_QUEUE_ERROR; | |
a98755c5 AH |
285 | } |
286 | ||
74c45052 | 287 | if (bd->last && virtqueue_kick_prepare(vblk->vqs[qid].vq)) |
e8edca6f | 288 | notify = true; |
6a27b656 | 289 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
e8edca6f ML |
290 | |
291 | if (notify) | |
6a27b656 | 292 | virtqueue_notify(vblk->vqs[qid].vq); |
1cf7e9c6 | 293 | return BLK_MQ_RQ_QUEUE_OK; |
a98755c5 AH |
294 | } |
295 | ||
4cb2ea28 | 296 | /* return id (s/n) string for *disk to *id_str |
297 | */ | |
298 | static int virtblk_get_id(struct gendisk *disk, char *id_str) | |
299 | { | |
300 | struct virtio_blk *vblk = disk->private_data; | |
f9596695 | 301 | struct request_queue *q = vblk->disk->queue; |
4cb2ea28 | 302 | struct request *req; |
e4c4776d | 303 | int err; |
4cb2ea28 | 304 | |
aebf526b | 305 | req = blk_get_request(q, REQ_OP_DRV_IN, GFP_KERNEL); |
f9596695 | 306 | if (IS_ERR(req)) |
4cb2ea28 | 307 | return PTR_ERR(req); |
f9596695 CH |
308 | |
309 | err = blk_rq_map_kern(q, req, id_str, VIRTIO_BLK_ID_BYTES, GFP_KERNEL); | |
310 | if (err) | |
311 | goto out; | |
312 | ||
e4c4776d | 313 | err = blk_execute_rq(vblk->disk->queue, vblk->disk, req, false); |
f9596695 | 314 | out: |
e4c4776d | 315 | blk_put_request(req); |
e4c4776d | 316 | return err; |
4cb2ea28 | 317 | } |
318 | ||
135da0b0 CB |
319 | /* We provide getgeo only to please some old bootloader/partitioning tools */ |
320 | static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo) | |
321 | { | |
48e4043d | 322 | struct virtio_blk *vblk = bd->bd_disk->private_data; |
48e4043d RH |
323 | |
324 | /* see if the host passed in geometry config */ | |
855e0c52 RR |
325 | if (virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_GEOMETRY)) { |
326 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
327 | geometry.cylinders, &geo->cylinders); | |
328 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
329 | geometry.heads, &geo->heads); | |
330 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
331 | geometry.sectors, &geo->sectors); | |
48e4043d RH |
332 | } else { |
333 | /* some standard values, similar to sd */ | |
334 | geo->heads = 1 << 6; | |
335 | geo->sectors = 1 << 5; | |
336 | geo->cylinders = get_capacity(bd->bd_disk) >> 11; | |
337 | } | |
135da0b0 CB |
338 | return 0; |
339 | } | |
340 | ||
83d5cde4 | 341 | static const struct block_device_operations virtblk_fops = { |
8a6cfeb6 | 342 | .ioctl = virtblk_ioctl, |
135da0b0 CB |
343 | .owner = THIS_MODULE, |
344 | .getgeo = virtblk_getgeo, | |
e467cde2 RR |
345 | }; |
346 | ||
d50ed907 CB |
347 | static int index_to_minor(int index) |
348 | { | |
349 | return index << PART_BITS; | |
350 | } | |
351 | ||
5087a50e MT |
352 | static int minor_to_index(int minor) |
353 | { | |
354 | return minor >> PART_BITS; | |
355 | } | |
356 | ||
a5eb9e4f RH |
357 | static ssize_t virtblk_serial_show(struct device *dev, |
358 | struct device_attribute *attr, char *buf) | |
359 | { | |
360 | struct gendisk *disk = dev_to_disk(dev); | |
361 | int err; | |
362 | ||
363 | /* sysfs gives us a PAGE_SIZE buffer */ | |
364 | BUILD_BUG_ON(PAGE_SIZE < VIRTIO_BLK_ID_BYTES); | |
365 | ||
366 | buf[VIRTIO_BLK_ID_BYTES] = '\0'; | |
367 | err = virtblk_get_id(disk, buf); | |
368 | if (!err) | |
369 | return strlen(buf); | |
370 | ||
371 | if (err == -EIO) /* Unsupported? Make it empty. */ | |
372 | return 0; | |
373 | ||
374 | return err; | |
375 | } | |
393c525b MT |
376 | |
377 | static DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL); | |
a5eb9e4f | 378 | |
7a7c924c CH |
379 | static void virtblk_config_changed_work(struct work_struct *work) |
380 | { | |
381 | struct virtio_blk *vblk = | |
382 | container_of(work, struct virtio_blk, config_work); | |
383 | struct virtio_device *vdev = vblk->vdev; | |
384 | struct request_queue *q = vblk->disk->queue; | |
385 | char cap_str_2[10], cap_str_10[10]; | |
9d9598b8 | 386 | char *envp[] = { "RESIZE=1", NULL }; |
b9f28d86 | 387 | u64 capacity; |
7a7c924c CH |
388 | |
389 | /* Host must always specify the capacity. */ | |
855e0c52 | 390 | virtio_cread(vdev, struct virtio_blk_config, capacity, &capacity); |
7a7c924c CH |
391 | |
392 | /* If capacity is too big, truncate with warning. */ | |
393 | if ((sector_t)capacity != capacity) { | |
394 | dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n", | |
395 | (unsigned long long)capacity); | |
396 | capacity = (sector_t)-1; | |
397 | } | |
398 | ||
b9f28d86 JB |
399 | string_get_size(capacity, queue_logical_block_size(q), |
400 | STRING_UNITS_2, cap_str_2, sizeof(cap_str_2)); | |
401 | string_get_size(capacity, queue_logical_block_size(q), | |
402 | STRING_UNITS_10, cap_str_10, sizeof(cap_str_10)); | |
7a7c924c CH |
403 | |
404 | dev_notice(&vdev->dev, | |
405 | "new size: %llu %d-byte logical blocks (%s/%s)\n", | |
406 | (unsigned long long)capacity, | |
407 | queue_logical_block_size(q), | |
408 | cap_str_10, cap_str_2); | |
409 | ||
410 | set_capacity(vblk->disk, capacity); | |
e9986f30 | 411 | revalidate_disk(vblk->disk); |
9d9598b8 | 412 | kobject_uevent_env(&disk_to_dev(vblk->disk)->kobj, KOBJ_CHANGE, envp); |
7a7c924c CH |
413 | } |
414 | ||
415 | static void virtblk_config_changed(struct virtio_device *vdev) | |
416 | { | |
417 | struct virtio_blk *vblk = vdev->priv; | |
418 | ||
419 | queue_work(virtblk_wq, &vblk->config_work); | |
420 | } | |
421 | ||
6abd6e5a AS |
422 | static int init_vq(struct virtio_blk *vblk) |
423 | { | |
2ff98449 | 424 | int err; |
6a27b656 ML |
425 | int i; |
426 | vq_callback_t **callbacks; | |
427 | const char **names; | |
428 | struct virtqueue **vqs; | |
429 | unsigned short num_vqs; | |
430 | struct virtio_device *vdev = vblk->vdev; | |
ad71473d | 431 | struct irq_affinity desc = { 0, }; |
6a27b656 ML |
432 | |
433 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ, | |
434 | struct virtio_blk_config, num_queues, | |
435 | &num_vqs); | |
436 | if (err) | |
437 | num_vqs = 1; | |
438 | ||
668866b6 | 439 | vblk->vqs = kmalloc_array(num_vqs, sizeof(*vblk->vqs), GFP_KERNEL); |
347a5293 MH |
440 | if (!vblk->vqs) |
441 | return -ENOMEM; | |
6a27b656 | 442 | |
668866b6 ME |
443 | names = kmalloc_array(num_vqs, sizeof(*names), GFP_KERNEL); |
444 | callbacks = kmalloc_array(num_vqs, sizeof(*callbacks), GFP_KERNEL); | |
445 | vqs = kmalloc_array(num_vqs, sizeof(*vqs), GFP_KERNEL); | |
347a5293 MH |
446 | if (!names || !callbacks || !vqs) { |
447 | err = -ENOMEM; | |
448 | goto out; | |
449 | } | |
6abd6e5a | 450 | |
6a27b656 ML |
451 | for (i = 0; i < num_vqs; i++) { |
452 | callbacks[i] = virtblk_done; | |
453 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req.%d", i); | |
454 | names[i] = vblk->vqs[i].name; | |
455 | } | |
456 | ||
457 | /* Discover virtqueues and write information to configuration. */ | |
fb5e31d9 | 458 | err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names, |
ad71473d | 459 | &desc); |
6a27b656 | 460 | if (err) |
347a5293 | 461 | goto out; |
6abd6e5a | 462 | |
6a27b656 ML |
463 | for (i = 0; i < num_vqs; i++) { |
464 | spin_lock_init(&vblk->vqs[i].lock); | |
465 | vblk->vqs[i].vq = vqs[i]; | |
466 | } | |
467 | vblk->num_vqs = num_vqs; | |
468 | ||
347a5293 | 469 | out: |
6a27b656 | 470 | kfree(vqs); |
6a27b656 | 471 | kfree(callbacks); |
6a27b656 | 472 | kfree(names); |
6a27b656 ML |
473 | if (err) |
474 | kfree(vblk->vqs); | |
6abd6e5a AS |
475 | return err; |
476 | } | |
477 | ||
c0aa3e09 RM |
478 | /* |
479 | * Legacy naming scheme used for virtio devices. We are stuck with it for | |
480 | * virtio blk but don't ever use it for any new driver. | |
481 | */ | |
482 | static int virtblk_name_format(char *prefix, int index, char *buf, int buflen) | |
483 | { | |
484 | const int base = 'z' - 'a' + 1; | |
485 | char *begin = buf + strlen(prefix); | |
486 | char *end = buf + buflen; | |
487 | char *p; | |
488 | int unit; | |
489 | ||
490 | p = end - 1; | |
491 | *p = '\0'; | |
492 | unit = base; | |
493 | do { | |
494 | if (p == begin) | |
495 | return -EINVAL; | |
496 | *--p = 'a' + (index % unit); | |
497 | index = (index / unit) - 1; | |
498 | } while (index >= 0); | |
499 | ||
500 | memmove(begin, p, end - p); | |
501 | memcpy(buf, prefix, strlen(prefix)); | |
502 | ||
503 | return 0; | |
504 | } | |
505 | ||
cd5d5038 PB |
506 | static int virtblk_get_cache_mode(struct virtio_device *vdev) |
507 | { | |
508 | u8 writeback; | |
509 | int err; | |
510 | ||
855e0c52 RR |
511 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE, |
512 | struct virtio_blk_config, wce, | |
513 | &writeback); | |
592002f5 MT |
514 | |
515 | /* | |
516 | * If WCE is not configurable and flush is not available, | |
517 | * assume no writeback cache is in use. | |
518 | */ | |
cd5d5038 | 519 | if (err) |
592002f5 | 520 | writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH); |
cd5d5038 PB |
521 | |
522 | return writeback; | |
523 | } | |
524 | ||
525 | static void virtblk_update_cache_mode(struct virtio_device *vdev) | |
526 | { | |
527 | u8 writeback = virtblk_get_cache_mode(vdev); | |
528 | struct virtio_blk *vblk = vdev->priv; | |
529 | ||
ad9126ac | 530 | blk_queue_write_cache(vblk->disk->queue, writeback, false); |
cd5d5038 PB |
531 | revalidate_disk(vblk->disk); |
532 | } | |
533 | ||
534 | static const char *const virtblk_cache_types[] = { | |
535 | "write through", "write back" | |
536 | }; | |
537 | ||
538 | static ssize_t | |
539 | virtblk_cache_type_store(struct device *dev, struct device_attribute *attr, | |
540 | const char *buf, size_t count) | |
541 | { | |
542 | struct gendisk *disk = dev_to_disk(dev); | |
543 | struct virtio_blk *vblk = disk->private_data; | |
544 | struct virtio_device *vdev = vblk->vdev; | |
545 | int i; | |
cd5d5038 PB |
546 | |
547 | BUG_ON(!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_CONFIG_WCE)); | |
548 | for (i = ARRAY_SIZE(virtblk_cache_types); --i >= 0; ) | |
549 | if (sysfs_streq(buf, virtblk_cache_types[i])) | |
550 | break; | |
551 | ||
552 | if (i < 0) | |
553 | return -EINVAL; | |
554 | ||
855e0c52 | 555 | virtio_cwrite8(vdev, offsetof(struct virtio_blk_config, wce), i); |
cd5d5038 PB |
556 | virtblk_update_cache_mode(vdev); |
557 | return count; | |
558 | } | |
559 | ||
560 | static ssize_t | |
561 | virtblk_cache_type_show(struct device *dev, struct device_attribute *attr, | |
562 | char *buf) | |
563 | { | |
564 | struct gendisk *disk = dev_to_disk(dev); | |
565 | struct virtio_blk *vblk = disk->private_data; | |
566 | u8 writeback = virtblk_get_cache_mode(vblk->vdev); | |
567 | ||
568 | BUG_ON(writeback >= ARRAY_SIZE(virtblk_cache_types)); | |
569 | return snprintf(buf, 40, "%s\n", virtblk_cache_types[writeback]); | |
570 | } | |
571 | ||
572 | static const struct device_attribute dev_attr_cache_type_ro = | |
573 | __ATTR(cache_type, S_IRUGO, | |
574 | virtblk_cache_type_show, NULL); | |
575 | static const struct device_attribute dev_attr_cache_type_rw = | |
576 | __ATTR(cache_type, S_IRUGO|S_IWUSR, | |
577 | virtblk_cache_type_show, virtblk_cache_type_store); | |
578 | ||
24d2f903 CH |
579 | static int virtblk_init_request(void *data, struct request *rq, |
580 | unsigned int hctx_idx, unsigned int request_idx, | |
581 | unsigned int numa_node) | |
e9b267d9 CH |
582 | { |
583 | struct virtio_blk *vblk = data; | |
584 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(rq); | |
585 | ||
97b50a65 | 586 | #ifdef CONFIG_VIRTIO_BLK_SCSI |
82ed4db4 | 587 | vbr->sreq.sense = vbr->sense; |
97b50a65 | 588 | #endif |
e9b267d9 CH |
589 | sg_init_table(vbr->sg, vblk->sg_elems); |
590 | return 0; | |
591 | } | |
592 | ||
ad71473d CH |
593 | static int virtblk_map_queues(struct blk_mq_tag_set *set) |
594 | { | |
595 | struct virtio_blk *vblk = set->driver_data; | |
596 | ||
597 | return blk_mq_virtio_map_queues(set, vblk->vdev, 0); | |
598 | } | |
599 | ||
f363b089 | 600 | static const struct blk_mq_ops virtio_mq_ops = { |
1cf7e9c6 | 601 | .queue_rq = virtio_queue_rq, |
5124c285 | 602 | .complete = virtblk_request_done, |
24d2f903 | 603 | .init_request = virtblk_init_request, |
ad71473d | 604 | .map_queues = virtblk_map_queues, |
1cf7e9c6 JA |
605 | }; |
606 | ||
24d2f903 CH |
607 | static unsigned int virtblk_queue_depth; |
608 | module_param_named(queue_depth, virtblk_queue_depth, uint, 0444); | |
1cf7e9c6 | 609 | |
8d85fce7 | 610 | static int virtblk_probe(struct virtio_device *vdev) |
e467cde2 RR |
611 | { |
612 | struct virtio_blk *vblk; | |
69740c8b | 613 | struct request_queue *q; |
5087a50e | 614 | int err, index; |
a98755c5 | 615 | |
e467cde2 | 616 | u64 cap; |
69740c8b CH |
617 | u32 v, blk_size, sg_elems, opt_io_size; |
618 | u16 min_io_size; | |
619 | u8 physical_block_exp, alignment_offset; | |
e467cde2 | 620 | |
a4379fd8 MT |
621 | if (!vdev->config->get) { |
622 | dev_err(&vdev->dev, "%s failure: config access disabled\n", | |
623 | __func__); | |
624 | return -EINVAL; | |
625 | } | |
626 | ||
5087a50e MT |
627 | err = ida_simple_get(&vd_index_ida, 0, minor_to_index(1 << MINORBITS), |
628 | GFP_KERNEL); | |
629 | if (err < 0) | |
630 | goto out; | |
631 | index = err; | |
4f3bf19c | 632 | |
0864b79a | 633 | /* We need to know how many segments before we allocate. */ |
855e0c52 RR |
634 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SEG_MAX, |
635 | struct virtio_blk_config, seg_max, | |
636 | &sg_elems); | |
a5b365a6 CH |
637 | |
638 | /* We need at least one SG element, whatever they say. */ | |
639 | if (err || !sg_elems) | |
0864b79a RR |
640 | sg_elems = 1; |
641 | ||
642 | /* We need an extra sg elements at head and tail. */ | |
643 | sg_elems += 2; | |
1cf7e9c6 | 644 | vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL); |
e467cde2 RR |
645 | if (!vblk) { |
646 | err = -ENOMEM; | |
5087a50e | 647 | goto out_free_index; |
e467cde2 RR |
648 | } |
649 | ||
e467cde2 | 650 | vblk->vdev = vdev; |
0864b79a | 651 | vblk->sg_elems = sg_elems; |
a98755c5 | 652 | |
7a7c924c | 653 | INIT_WORK(&vblk->config_work, virtblk_config_changed_work); |
e467cde2 | 654 | |
6abd6e5a AS |
655 | err = init_vq(vblk); |
656 | if (err) | |
e467cde2 | 657 | goto out_free_vblk; |
e467cde2 | 658 | |
e467cde2 | 659 | /* FIXME: How many partitions? How long is a piece of string? */ |
4f3bf19c | 660 | vblk->disk = alloc_disk(1 << PART_BITS); |
e467cde2 RR |
661 | if (!vblk->disk) { |
662 | err = -ENOMEM; | |
1cf7e9c6 | 663 | goto out_free_vq; |
e467cde2 RR |
664 | } |
665 | ||
fc4324b4 | 666 | /* Default queue sizing is to fill the ring. */ |
24d2f903 | 667 | if (!virtblk_queue_depth) { |
6a27b656 | 668 | virtblk_queue_depth = vblk->vqs[0].vq->num_free; |
fc4324b4 RR |
669 | /* ... but without indirect descs, we use 2 descs per req */ |
670 | if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC)) | |
24d2f903 | 671 | virtblk_queue_depth /= 2; |
fc4324b4 | 672 | } |
24d2f903 CH |
673 | |
674 | memset(&vblk->tag_set, 0, sizeof(vblk->tag_set)); | |
675 | vblk->tag_set.ops = &virtio_mq_ops; | |
24d2f903 CH |
676 | vblk->tag_set.queue_depth = virtblk_queue_depth; |
677 | vblk->tag_set.numa_node = NUMA_NO_NODE; | |
678 | vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; | |
679 | vblk->tag_set.cmd_size = | |
1cf7e9c6 JA |
680 | sizeof(struct virtblk_req) + |
681 | sizeof(struct scatterlist) * sg_elems; | |
24d2f903 | 682 | vblk->tag_set.driver_data = vblk; |
6a27b656 | 683 | vblk->tag_set.nr_hw_queues = vblk->num_vqs; |
1cf7e9c6 | 684 | |
24d2f903 CH |
685 | err = blk_mq_alloc_tag_set(&vblk->tag_set); |
686 | if (err) | |
687 | goto out_put_disk; | |
688 | ||
6bf6b0aa | 689 | q = blk_mq_init_queue(&vblk->tag_set); |
35b489d3 | 690 | if (IS_ERR(q)) { |
e467cde2 | 691 | err = -ENOMEM; |
24d2f903 | 692 | goto out_free_tags; |
e467cde2 | 693 | } |
6bf6b0aa | 694 | vblk->disk->queue = q; |
e467cde2 | 695 | |
69740c8b | 696 | q->queuedata = vblk; |
7d116b62 | 697 | |
c0aa3e09 | 698 | virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN); |
d50ed907 | 699 | |
e467cde2 | 700 | vblk->disk->major = major; |
d50ed907 | 701 | vblk->disk->first_minor = index_to_minor(index); |
e467cde2 RR |
702 | vblk->disk->private_data = vblk; |
703 | vblk->disk->fops = &virtblk_fops; | |
5fa3142d | 704 | vblk->disk->flags |= GENHD_FL_EXT_DEVT; |
5087a50e | 705 | vblk->index = index; |
4f3bf19c | 706 | |
02c42b7a | 707 | /* configure queue flush support */ |
cd5d5038 | 708 | virtblk_update_cache_mode(vdev); |
e467cde2 | 709 | |
3ef53609 CB |
710 | /* If disk is read-only in the host, the guest should obey */ |
711 | if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO)) | |
712 | set_disk_ro(vblk->disk, 1); | |
713 | ||
a586d4f6 | 714 | /* Host must always specify the capacity. */ |
855e0c52 | 715 | virtio_cread(vdev, struct virtio_blk_config, capacity, &cap); |
e467cde2 RR |
716 | |
717 | /* If capacity is too big, truncate with warning. */ | |
718 | if ((sector_t)cap != cap) { | |
719 | dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n", | |
720 | (unsigned long long)cap); | |
721 | cap = (sector_t)-1; | |
722 | } | |
723 | set_capacity(vblk->disk, cap); | |
724 | ||
0864b79a | 725 | /* We can handle whatever the host told us to handle. */ |
ee714f2d | 726 | blk_queue_max_segments(q, vblk->sg_elems-2); |
0864b79a | 727 | |
4eff3cae | 728 | /* No need to bounce any requests */ |
69740c8b | 729 | blk_queue_bounce_limit(q, BLK_BOUNCE_ANY); |
4eff3cae | 730 | |
4b7f7e20 | 731 | /* No real sector limit. */ |
ee714f2d | 732 | blk_queue_max_hw_sectors(q, -1U); |
4b7f7e20 | 733 | |
a586d4f6 RR |
734 | /* Host can optionally specify maximum segment size and number of |
735 | * segments. */ | |
855e0c52 RR |
736 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SIZE_MAX, |
737 | struct virtio_blk_config, size_max, &v); | |
e467cde2 | 738 | if (!err) |
69740c8b | 739 | blk_queue_max_segment_size(q, v); |
4b7f7e20 | 740 | else |
69740c8b | 741 | blk_queue_max_segment_size(q, -1U); |
e467cde2 | 742 | |
066f4d82 | 743 | /* Host can optionally specify the block size of the device */ |
855e0c52 RR |
744 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE, |
745 | struct virtio_blk_config, blk_size, | |
746 | &blk_size); | |
066f4d82 | 747 | if (!err) |
69740c8b CH |
748 | blk_queue_logical_block_size(q, blk_size); |
749 | else | |
750 | blk_size = queue_logical_block_size(q); | |
751 | ||
752 | /* Use topology information if available */ | |
855e0c52 RR |
753 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
754 | struct virtio_blk_config, physical_block_exp, | |
755 | &physical_block_exp); | |
69740c8b CH |
756 | if (!err && physical_block_exp) |
757 | blk_queue_physical_block_size(q, | |
758 | blk_size * (1 << physical_block_exp)); | |
759 | ||
855e0c52 RR |
760 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
761 | struct virtio_blk_config, alignment_offset, | |
762 | &alignment_offset); | |
69740c8b CH |
763 | if (!err && alignment_offset) |
764 | blk_queue_alignment_offset(q, blk_size * alignment_offset); | |
765 | ||
855e0c52 RR |
766 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
767 | struct virtio_blk_config, min_io_size, | |
768 | &min_io_size); | |
69740c8b CH |
769 | if (!err && min_io_size) |
770 | blk_queue_io_min(q, blk_size * min_io_size); | |
771 | ||
855e0c52 RR |
772 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
773 | struct virtio_blk_config, opt_io_size, | |
774 | &opt_io_size); | |
69740c8b CH |
775 | if (!err && opt_io_size) |
776 | blk_queue_io_opt(q, blk_size * opt_io_size); | |
777 | ||
7a11370e MT |
778 | virtio_device_ready(vdev); |
779 | ||
0d52c756 | 780 | device_add_disk(&vdev->dev, vblk->disk); |
a5eb9e4f RH |
781 | err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial); |
782 | if (err) | |
783 | goto out_del_disk; | |
784 | ||
cd5d5038 PB |
785 | if (virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) |
786 | err = device_create_file(disk_to_dev(vblk->disk), | |
787 | &dev_attr_cache_type_rw); | |
788 | else | |
789 | err = device_create_file(disk_to_dev(vblk->disk), | |
790 | &dev_attr_cache_type_ro); | |
791 | if (err) | |
792 | goto out_del_disk; | |
e467cde2 RR |
793 | return 0; |
794 | ||
a5eb9e4f RH |
795 | out_del_disk: |
796 | del_gendisk(vblk->disk); | |
797 | blk_cleanup_queue(vblk->disk->queue); | |
24d2f903 CH |
798 | out_free_tags: |
799 | blk_mq_free_tag_set(&vblk->tag_set); | |
e467cde2 RR |
800 | out_put_disk: |
801 | put_disk(vblk->disk); | |
e467cde2 | 802 | out_free_vq: |
d2a7ddda | 803 | vdev->config->del_vqs(vdev); |
e467cde2 RR |
804 | out_free_vblk: |
805 | kfree(vblk); | |
5087a50e MT |
806 | out_free_index: |
807 | ida_simple_remove(&vd_index_ida, index); | |
e467cde2 RR |
808 | out: |
809 | return err; | |
810 | } | |
811 | ||
8d85fce7 | 812 | static void virtblk_remove(struct virtio_device *vdev) |
e467cde2 RR |
813 | { |
814 | struct virtio_blk *vblk = vdev->priv; | |
5087a50e | 815 | int index = vblk->index; |
f4953fe6 | 816 | int refc; |
e467cde2 | 817 | |
cc74f719 MT |
818 | /* Make sure no work handler is accessing the device. */ |
819 | flush_work(&vblk->config_work); | |
7a7c924c | 820 | |
02e2b124 | 821 | del_gendisk(vblk->disk); |
483001c7 | 822 | blk_cleanup_queue(vblk->disk->queue); |
02e2b124 | 823 | |
24d2f903 CH |
824 | blk_mq_free_tag_set(&vblk->tag_set); |
825 | ||
6e5aa7ef RR |
826 | /* Stop all the virtqueues. */ |
827 | vdev->config->reset(vdev); | |
828 | ||
2c935bc5 | 829 | refc = kref_read(&disk_to_dev(vblk->disk)->kobj.kref); |
e467cde2 | 830 | put_disk(vblk->disk); |
d2a7ddda | 831 | vdev->config->del_vqs(vdev); |
6a27b656 | 832 | kfree(vblk->vqs); |
e467cde2 | 833 | kfree(vblk); |
f4953fe6 AG |
834 | |
835 | /* Only free device id if we don't have any users */ | |
836 | if (refc == 1) | |
837 | ida_simple_remove(&vd_index_ida, index); | |
e467cde2 RR |
838 | } |
839 | ||
89107000 | 840 | #ifdef CONFIG_PM_SLEEP |
f8fb5bc2 AS |
841 | static int virtblk_freeze(struct virtio_device *vdev) |
842 | { | |
843 | struct virtio_blk *vblk = vdev->priv; | |
844 | ||
845 | /* Ensure we don't receive any more interrupts */ | |
846 | vdev->config->reset(vdev); | |
847 | ||
cc74f719 | 848 | /* Make sure no work handler is accessing the device. */ |
f8fb5bc2 AS |
849 | flush_work(&vblk->config_work); |
850 | ||
1cf7e9c6 | 851 | blk_mq_stop_hw_queues(vblk->disk->queue); |
f8fb5bc2 AS |
852 | |
853 | vdev->config->del_vqs(vdev); | |
854 | return 0; | |
855 | } | |
856 | ||
857 | static int virtblk_restore(struct virtio_device *vdev) | |
858 | { | |
859 | struct virtio_blk *vblk = vdev->priv; | |
860 | int ret; | |
861 | ||
f8fb5bc2 | 862 | ret = init_vq(vdev->priv); |
6d62c37f MT |
863 | if (ret) |
864 | return ret; | |
865 | ||
866 | virtio_device_ready(vdev); | |
1cf7e9c6 | 867 | |
6d62c37f MT |
868 | blk_mq_start_stopped_hw_queues(vblk->disk->queue, true); |
869 | return 0; | |
f8fb5bc2 AS |
870 | } |
871 | #endif | |
872 | ||
47483e25 | 873 | static const struct virtio_device_id id_table[] = { |
e467cde2 RR |
874 | { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID }, |
875 | { 0 }, | |
876 | }; | |
877 | ||
19c1c5a6 | 878 | static unsigned int features_legacy[] = { |
02c42b7a | 879 | VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY, |
97b50a65 CH |
880 | VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, |
881 | #ifdef CONFIG_VIRTIO_BLK_SCSI | |
882 | VIRTIO_BLK_F_SCSI, | |
883 | #endif | |
592002f5 | 884 | VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE, |
6a27b656 | 885 | VIRTIO_BLK_F_MQ, |
19c1c5a6 MT |
886 | } |
887 | ; | |
888 | static unsigned int features[] = { | |
889 | VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY, | |
890 | VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, | |
592002f5 | 891 | VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE, |
19c1c5a6 | 892 | VIRTIO_BLK_F_MQ, |
c45a6816 RR |
893 | }; |
894 | ||
8d85fce7 | 895 | static struct virtio_driver virtio_blk = { |
19c1c5a6 MT |
896 | .feature_table = features, |
897 | .feature_table_size = ARRAY_SIZE(features), | |
898 | .feature_table_legacy = features_legacy, | |
899 | .feature_table_size_legacy = ARRAY_SIZE(features_legacy), | |
900 | .driver.name = KBUILD_MODNAME, | |
901 | .driver.owner = THIS_MODULE, | |
902 | .id_table = id_table, | |
903 | .probe = virtblk_probe, | |
904 | .remove = virtblk_remove, | |
905 | .config_changed = virtblk_config_changed, | |
89107000 | 906 | #ifdef CONFIG_PM_SLEEP |
19c1c5a6 MT |
907 | .freeze = virtblk_freeze, |
908 | .restore = virtblk_restore, | |
f8fb5bc2 | 909 | #endif |
e467cde2 RR |
910 | }; |
911 | ||
912 | static int __init init(void) | |
913 | { | |
7a7c924c CH |
914 | int error; |
915 | ||
916 | virtblk_wq = alloc_workqueue("virtio-blk", 0, 0); | |
917 | if (!virtblk_wq) | |
918 | return -ENOMEM; | |
919 | ||
4f3bf19c | 920 | major = register_blkdev(0, "virtblk"); |
7a7c924c CH |
921 | if (major < 0) { |
922 | error = major; | |
923 | goto out_destroy_workqueue; | |
924 | } | |
925 | ||
926 | error = register_virtio_driver(&virtio_blk); | |
927 | if (error) | |
928 | goto out_unregister_blkdev; | |
929 | return 0; | |
930 | ||
931 | out_unregister_blkdev: | |
932 | unregister_blkdev(major, "virtblk"); | |
933 | out_destroy_workqueue: | |
934 | destroy_workqueue(virtblk_wq); | |
935 | return error; | |
e467cde2 RR |
936 | } |
937 | ||
938 | static void __exit fini(void) | |
939 | { | |
940 | unregister_virtio_driver(&virtio_blk); | |
38f37b57 | 941 | unregister_blkdev(major, "virtblk"); |
7a7c924c | 942 | destroy_workqueue(virtblk_wq); |
e467cde2 RR |
943 | } |
944 | module_init(init); | |
945 | module_exit(fini); | |
946 | ||
947 | MODULE_DEVICE_TABLE(virtio, id_table); | |
948 | MODULE_DESCRIPTION("Virtio block driver"); | |
949 | MODULE_LICENSE("GPL"); |