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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> |
e467cde2 RR |
8 | #include <linux/virtio.h> |
9 | #include <linux/virtio_blk.h> | |
3d1266c7 | 10 | #include <linux/scatterlist.h> |
7a7c924c | 11 | #include <linux/string_helpers.h> |
6917f83f | 12 | #include <scsi/scsi_cmnd.h> |
5087a50e | 13 | #include <linux/idr.h> |
1cf7e9c6 JA |
14 | #include <linux/blk-mq.h> |
15 | #include <linux/numa.h> | |
3d1266c7 | 16 | |
4f3bf19c | 17 | #define PART_BITS 4 |
6a27b656 | 18 | #define VQ_NAME_LEN 16 |
e467cde2 | 19 | |
5087a50e MT |
20 | static int major; |
21 | static DEFINE_IDA(vd_index_ida); | |
22 | ||
2a647bfe | 23 | static struct workqueue_struct *virtblk_wq; |
4f3bf19c | 24 | |
6a27b656 ML |
25 | struct virtio_blk_vq { |
26 | struct virtqueue *vq; | |
27 | spinlock_t lock; | |
28 | char name[VQ_NAME_LEN]; | |
29 | } ____cacheline_aligned_in_smp; | |
30 | ||
bb6ec576 | 31 | struct virtio_blk { |
e467cde2 | 32 | struct virtio_device *vdev; |
e467cde2 RR |
33 | |
34 | /* The disk structure for the kernel. */ | |
35 | struct gendisk *disk; | |
36 | ||
24d2f903 CH |
37 | /* Block layer tags. */ |
38 | struct blk_mq_tag_set tag_set; | |
39 | ||
7a7c924c CH |
40 | /* Process context for config space updates */ |
41 | struct work_struct config_work; | |
42 | ||
0864b79a RR |
43 | /* What host tells us, plus 2 for header & tailer. */ |
44 | unsigned int sg_elems; | |
45 | ||
5087a50e MT |
46 | /* Ida index - used to track minor number allocations. */ |
47 | int index; | |
6a27b656 ML |
48 | |
49 | /* num of vqs */ | |
50 | int num_vqs; | |
51 | struct virtio_blk_vq *vqs; | |
e467cde2 RR |
52 | }; |
53 | ||
bb6ec576 | 54 | struct virtblk_req { |
97b50a65 CH |
55 | #ifdef CONFIG_VIRTIO_BLK_SCSI |
56 | struct scsi_request sreq; /* for SCSI passthrough, must be first */ | |
57 | u8 sense[SCSI_SENSE_BUFFERSIZE]; | |
1cde26f9 | 58 | struct virtio_scsi_inhdr in_hdr; |
97b50a65 CH |
59 | #endif |
60 | struct virtio_blk_outhdr out_hdr; | |
cb38fa23 | 61 | u8 status; |
a98755c5 | 62 | struct scatterlist sg[]; |
e467cde2 RR |
63 | }; |
64 | ||
a98755c5 AH |
65 | static inline int virtblk_result(struct virtblk_req *vbr) |
66 | { | |
67 | switch (vbr->status) { | |
68 | case VIRTIO_BLK_S_OK: | |
69 | return 0; | |
70 | case VIRTIO_BLK_S_UNSUPP: | |
71 | return -ENOTTY; | |
72 | default: | |
73 | return -EIO; | |
74 | } | |
75 | } | |
76 | ||
97b50a65 CH |
77 | /* |
78 | * If this is a packet command we need a couple of additional headers. Behind | |
79 | * the normal outhdr we put a segment with the scsi command block, and before | |
80 | * the normal inhdr we put the sense data and the inhdr with additional status | |
81 | * information. | |
82 | */ | |
83 | #ifdef CONFIG_VIRTIO_BLK_SCSI | |
84 | static int virtblk_add_req_scsi(struct virtqueue *vq, struct virtblk_req *vbr, | |
85 | struct scatterlist *data_sg, bool have_data) | |
c85a1f91 | 86 | { |
20af3cfd | 87 | struct scatterlist hdr, status, cmd, sense, inhdr, *sgs[6]; |
8f39db9d PB |
88 | unsigned int num_out = 0, num_in = 0; |
89 | ||
90 | sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr)); | |
91 | sgs[num_out++] = &hdr; | |
97b50a65 CH |
92 | sg_init_one(&cmd, vbr->sreq.cmd, vbr->sreq.cmd_len); |
93 | sgs[num_out++] = &cmd; | |
94 | ||
95 | if (have_data) { | |
96 | if (vbr->out_hdr.type & cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT)) | |
97 | sgs[num_out++] = data_sg; | |
98 | else | |
99 | sgs[num_out + num_in++] = data_sg; | |
100 | } | |
101 | ||
102 | sg_init_one(&sense, vbr->sense, SCSI_SENSE_BUFFERSIZE); | |
103 | sgs[num_out + num_in++] = &sense; | |
104 | sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr)); | |
105 | sgs[num_out + num_in++] = &inhdr; | |
106 | sg_init_one(&status, &vbr->status, sizeof(vbr->status)); | |
107 | sgs[num_out + num_in++] = &status; | |
108 | ||
109 | return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC); | |
110 | } | |
111 | ||
112 | static inline void virtblk_scsi_reques_done(struct request *req) | |
113 | { | |
114 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); | |
115 | struct virtio_blk *vblk = req->q->queuedata; | |
116 | struct scsi_request *sreq = &vbr->sreq; | |
117 | ||
118 | sreq->resid_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.residual); | |
119 | sreq->sense_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.sense_len); | |
120 | req->errors = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.errors); | |
121 | } | |
122 | ||
123 | static int virtblk_ioctl(struct block_device *bdev, fmode_t mode, | |
124 | unsigned int cmd, unsigned long data) | |
125 | { | |
126 | struct gendisk *disk = bdev->bd_disk; | |
127 | struct virtio_blk *vblk = disk->private_data; | |
8f39db9d | 128 | |
20af3cfd | 129 | /* |
97b50a65 | 130 | * Only allow the generic SCSI ioctls if the host can support it. |
20af3cfd | 131 | */ |
97b50a65 CH |
132 | if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI)) |
133 | return -ENOTTY; | |
134 | ||
135 | return scsi_cmd_blk_ioctl(bdev, mode, cmd, | |
136 | (void __user *)data); | |
137 | } | |
138 | #else | |
139 | static inline int virtblk_add_req_scsi(struct virtqueue *vq, | |
140 | struct virtblk_req *vbr, struct scatterlist *data_sg, | |
141 | bool have_data) | |
142 | { | |
143 | return -EIO; | |
144 | } | |
145 | static inline void virtblk_scsi_reques_done(struct request *req) | |
146 | { | |
147 | } | |
148 | #define virtblk_ioctl NULL | |
149 | #endif /* CONFIG_VIRTIO_BLK_SCSI */ | |
150 | ||
151 | static int virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr, | |
152 | struct scatterlist *data_sg, bool have_data) | |
153 | { | |
154 | struct scatterlist hdr, status, *sgs[3]; | |
155 | unsigned int num_out = 0, num_in = 0; | |
156 | ||
157 | sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr)); | |
158 | sgs[num_out++] = &hdr; | |
20af3cfd | 159 | |
0a11cc36 | 160 | if (have_data) { |
19c1c5a6 | 161 | if (vbr->out_hdr.type & cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT)) |
20af3cfd | 162 | sgs[num_out++] = data_sg; |
8f39db9d | 163 | else |
20af3cfd PB |
164 | sgs[num_out + num_in++] = data_sg; |
165 | } | |
166 | ||
8f39db9d PB |
167 | sg_init_one(&status, &vbr->status, sizeof(vbr->status)); |
168 | sgs[num_out + num_in++] = &status; | |
169 | ||
170 | return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC); | |
5ee21a52 PB |
171 | } |
172 | ||
5124c285 | 173 | static inline void virtblk_request_done(struct request *req) |
a98755c5 | 174 | { |
9d74e257 | 175 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); |
a98755c5 AH |
176 | int error = virtblk_result(vbr); |
177 | ||
97b50a65 CH |
178 | switch (req->cmd_type) { |
179 | case REQ_TYPE_BLOCK_PC: | |
180 | virtblk_scsi_reques_done(req); | |
181 | break; | |
182 | case REQ_TYPE_DRV_PRIV: | |
a98755c5 | 183 | req->errors = (error != 0); |
97b50a65 | 184 | break; |
a98755c5 AH |
185 | } |
186 | ||
c8a446ad | 187 | blk_mq_end_request(req, error); |
a98755c5 AH |
188 | } |
189 | ||
190 | static void virtblk_done(struct virtqueue *vq) | |
e467cde2 RR |
191 | { |
192 | struct virtio_blk *vblk = vq->vdev->priv; | |
1cf7e9c6 | 193 | bool req_done = false; |
6a27b656 | 194 | int qid = vq->index; |
e467cde2 | 195 | struct virtblk_req *vbr; |
e467cde2 | 196 | unsigned long flags; |
a98755c5 | 197 | unsigned int len; |
e467cde2 | 198 | |
6a27b656 | 199 | spin_lock_irqsave(&vblk->vqs[qid].lock, flags); |
bb811108 AH |
200 | do { |
201 | virtqueue_disable_cb(vq); | |
6a27b656 | 202 | while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) { |
85dada09 CH |
203 | struct request *req = blk_mq_rq_from_pdu(vbr); |
204 | ||
205 | blk_mq_complete_request(req, req->errors); | |
1cf7e9c6 | 206 | req_done = true; |
33659ebb | 207 | } |
7f03b17d HG |
208 | if (unlikely(virtqueue_is_broken(vq))) |
209 | break; | |
bb811108 | 210 | } while (!virtqueue_enable_cb(vq)); |
1cf7e9c6 | 211 | |
e467cde2 | 212 | /* In case queue is stopped waiting for more buffers. */ |
a98755c5 | 213 | if (req_done) |
1b4a3258 | 214 | blk_mq_start_stopped_hw_queues(vblk->disk->queue, true); |
6a27b656 | 215 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
a98755c5 AH |
216 | } |
217 | ||
74c45052 JA |
218 | static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, |
219 | const struct blk_mq_queue_data *bd) | |
e467cde2 | 220 | { |
1cf7e9c6 | 221 | struct virtio_blk *vblk = hctx->queue->queuedata; |
74c45052 | 222 | struct request *req = bd->rq; |
9d74e257 | 223 | struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); |
1cf7e9c6 | 224 | unsigned long flags; |
20af3cfd | 225 | unsigned int num; |
6a27b656 | 226 | int qid = hctx->queue_num; |
5261b85e | 227 | int err; |
e8edca6f | 228 | bool notify = false; |
e467cde2 | 229 | |
1cf7e9c6 | 230 | BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems); |
e467cde2 | 231 | |
3a5e02ce | 232 | if (req_op(req) == REQ_OP_FLUSH) { |
19c1c5a6 | 233 | vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_FLUSH); |
4cb2ea28 | 234 | vbr->out_hdr.sector = 0; |
85dada09 | 235 | vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(req)); |
dd40e456 FT |
236 | } else { |
237 | switch (req->cmd_type) { | |
238 | case REQ_TYPE_FS: | |
239 | vbr->out_hdr.type = 0; | |
85dada09 CH |
240 | vbr->out_hdr.sector = cpu_to_virtio64(vblk->vdev, blk_rq_pos(req)); |
241 | vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(req)); | |
dd40e456 FT |
242 | break; |
243 | case REQ_TYPE_BLOCK_PC: | |
19c1c5a6 | 244 | vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_SCSI_CMD); |
f1b0ef06 | 245 | vbr->out_hdr.sector = 0; |
85dada09 | 246 | vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(req)); |
f1b0ef06 | 247 | break; |
4f8c9510 | 248 | case REQ_TYPE_DRV_PRIV: |
19c1c5a6 | 249 | vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_GET_ID); |
dd40e456 | 250 | vbr->out_hdr.sector = 0; |
85dada09 | 251 | vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(req)); |
dd40e456 FT |
252 | break; |
253 | default: | |
254 | /* We don't put anything else in the queue. */ | |
255 | BUG(); | |
f1b0ef06 | 256 | } |
e467cde2 RR |
257 | } |
258 | ||
e2490073 CH |
259 | blk_mq_start_request(req); |
260 | ||
85dada09 | 261 | num = blk_rq_map_sg(hctx->queue, req, vbr->sg); |
1cde26f9 | 262 | if (num) { |
85dada09 | 263 | if (rq_data_dir(req) == WRITE) |
19c1c5a6 | 264 | vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_OUT); |
20af3cfd | 265 | else |
19c1c5a6 | 266 | vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_IN); |
e467cde2 RR |
267 | } |
268 | ||
6a27b656 | 269 | spin_lock_irqsave(&vblk->vqs[qid].lock, flags); |
97b50a65 CH |
270 | if (req->cmd_type == REQ_TYPE_BLOCK_PC) |
271 | err = virtblk_add_req_scsi(vblk->vqs[qid].vq, vbr, vbr->sg, num); | |
272 | else | |
273 | err = virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num); | |
5261b85e | 274 | if (err) { |
6a27b656 | 275 | virtqueue_kick(vblk->vqs[qid].vq); |
1cf7e9c6 | 276 | blk_mq_stop_hw_queue(hctx); |
6a27b656 | 277 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
5261b85e RR |
278 | /* Out of mem doesn't actually happen, since we fall back |
279 | * to direct descriptors */ | |
280 | if (err == -ENOMEM || err == -ENOSPC) | |
281 | return BLK_MQ_RQ_QUEUE_BUSY; | |
282 | return BLK_MQ_RQ_QUEUE_ERROR; | |
a98755c5 AH |
283 | } |
284 | ||
74c45052 | 285 | if (bd->last && virtqueue_kick_prepare(vblk->vqs[qid].vq)) |
e8edca6f | 286 | notify = true; |
6a27b656 | 287 | spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags); |
e8edca6f ML |
288 | |
289 | if (notify) | |
6a27b656 | 290 | virtqueue_notify(vblk->vqs[qid].vq); |
1cf7e9c6 | 291 | return BLK_MQ_RQ_QUEUE_OK; |
a98755c5 AH |
292 | } |
293 | ||
4cb2ea28 | 294 | /* return id (s/n) string for *disk to *id_str |
295 | */ | |
296 | static int virtblk_get_id(struct gendisk *disk, char *id_str) | |
297 | { | |
298 | struct virtio_blk *vblk = disk->private_data; | |
f9596695 | 299 | struct request_queue *q = vblk->disk->queue; |
4cb2ea28 | 300 | struct request *req; |
e4c4776d | 301 | int err; |
4cb2ea28 | 302 | |
f9596695 CH |
303 | req = blk_get_request(q, READ, GFP_KERNEL); |
304 | if (IS_ERR(req)) | |
4cb2ea28 | 305 | return PTR_ERR(req); |
4f8c9510 | 306 | req->cmd_type = REQ_TYPE_DRV_PRIV; |
f9596695 CH |
307 | |
308 | err = blk_rq_map_kern(q, req, id_str, VIRTIO_BLK_ID_BYTES, GFP_KERNEL); | |
309 | if (err) | |
310 | goto out; | |
311 | ||
e4c4776d | 312 | err = blk_execute_rq(vblk->disk->queue, vblk->disk, req, false); |
f9596695 | 313 | out: |
e4c4776d | 314 | blk_put_request(req); |
e4c4776d | 315 | return err; |
4cb2ea28 | 316 | } |
317 | ||
135da0b0 CB |
318 | /* We provide getgeo only to please some old bootloader/partitioning tools */ |
319 | static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo) | |
320 | { | |
48e4043d | 321 | struct virtio_blk *vblk = bd->bd_disk->private_data; |
48e4043d RH |
322 | |
323 | /* see if the host passed in geometry config */ | |
855e0c52 RR |
324 | if (virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_GEOMETRY)) { |
325 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
326 | geometry.cylinders, &geo->cylinders); | |
327 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
328 | geometry.heads, &geo->heads); | |
329 | virtio_cread(vblk->vdev, struct virtio_blk_config, | |
330 | geometry.sectors, &geo->sectors); | |
48e4043d RH |
331 | } else { |
332 | /* some standard values, similar to sd */ | |
333 | geo->heads = 1 << 6; | |
334 | geo->sectors = 1 << 5; | |
335 | geo->cylinders = get_capacity(bd->bd_disk) >> 11; | |
336 | } | |
135da0b0 CB |
337 | return 0; |
338 | } | |
339 | ||
83d5cde4 | 340 | static const struct block_device_operations virtblk_fops = { |
8a6cfeb6 | 341 | .ioctl = virtblk_ioctl, |
135da0b0 CB |
342 | .owner = THIS_MODULE, |
343 | .getgeo = virtblk_getgeo, | |
e467cde2 RR |
344 | }; |
345 | ||
d50ed907 CB |
346 | static int index_to_minor(int index) |
347 | { | |
348 | return index << PART_BITS; | |
349 | } | |
350 | ||
5087a50e MT |
351 | static int minor_to_index(int minor) |
352 | { | |
353 | return minor >> PART_BITS; | |
354 | } | |
355 | ||
a5eb9e4f RH |
356 | static ssize_t virtblk_serial_show(struct device *dev, |
357 | struct device_attribute *attr, char *buf) | |
358 | { | |
359 | struct gendisk *disk = dev_to_disk(dev); | |
360 | int err; | |
361 | ||
362 | /* sysfs gives us a PAGE_SIZE buffer */ | |
363 | BUILD_BUG_ON(PAGE_SIZE < VIRTIO_BLK_ID_BYTES); | |
364 | ||
365 | buf[VIRTIO_BLK_ID_BYTES] = '\0'; | |
366 | err = virtblk_get_id(disk, buf); | |
367 | if (!err) | |
368 | return strlen(buf); | |
369 | ||
370 | if (err == -EIO) /* Unsupported? Make it empty. */ | |
371 | return 0; | |
372 | ||
373 | return err; | |
374 | } | |
393c525b MT |
375 | |
376 | static DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL); | |
a5eb9e4f | 377 | |
7a7c924c CH |
378 | static void virtblk_config_changed_work(struct work_struct *work) |
379 | { | |
380 | struct virtio_blk *vblk = | |
381 | container_of(work, struct virtio_blk, config_work); | |
382 | struct virtio_device *vdev = vblk->vdev; | |
383 | struct request_queue *q = vblk->disk->queue; | |
384 | char cap_str_2[10], cap_str_10[10]; | |
9d9598b8 | 385 | char *envp[] = { "RESIZE=1", NULL }; |
b9f28d86 | 386 | u64 capacity; |
7a7c924c CH |
387 | |
388 | /* Host must always specify the capacity. */ | |
855e0c52 | 389 | virtio_cread(vdev, struct virtio_blk_config, capacity, &capacity); |
7a7c924c CH |
390 | |
391 | /* If capacity is too big, truncate with warning. */ | |
392 | if ((sector_t)capacity != capacity) { | |
393 | dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n", | |
394 | (unsigned long long)capacity); | |
395 | capacity = (sector_t)-1; | |
396 | } | |
397 | ||
b9f28d86 JB |
398 | string_get_size(capacity, queue_logical_block_size(q), |
399 | STRING_UNITS_2, cap_str_2, sizeof(cap_str_2)); | |
400 | string_get_size(capacity, queue_logical_block_size(q), | |
401 | STRING_UNITS_10, cap_str_10, sizeof(cap_str_10)); | |
7a7c924c CH |
402 | |
403 | dev_notice(&vdev->dev, | |
404 | "new size: %llu %d-byte logical blocks (%s/%s)\n", | |
405 | (unsigned long long)capacity, | |
406 | queue_logical_block_size(q), | |
407 | cap_str_10, cap_str_2); | |
408 | ||
409 | set_capacity(vblk->disk, capacity); | |
e9986f30 | 410 | revalidate_disk(vblk->disk); |
9d9598b8 | 411 | kobject_uevent_env(&disk_to_dev(vblk->disk)->kobj, KOBJ_CHANGE, envp); |
7a7c924c CH |
412 | } |
413 | ||
414 | static void virtblk_config_changed(struct virtio_device *vdev) | |
415 | { | |
416 | struct virtio_blk *vblk = vdev->priv; | |
417 | ||
418 | queue_work(virtblk_wq, &vblk->config_work); | |
419 | } | |
420 | ||
6abd6e5a AS |
421 | static int init_vq(struct virtio_blk *vblk) |
422 | { | |
2ff98449 | 423 | int err; |
6a27b656 ML |
424 | int i; |
425 | vq_callback_t **callbacks; | |
426 | const char **names; | |
427 | struct virtqueue **vqs; | |
428 | unsigned short num_vqs; | |
429 | struct virtio_device *vdev = vblk->vdev; | |
430 | ||
431 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ, | |
432 | struct virtio_blk_config, num_queues, | |
433 | &num_vqs); | |
434 | if (err) | |
435 | num_vqs = 1; | |
436 | ||
668866b6 | 437 | vblk->vqs = kmalloc_array(num_vqs, sizeof(*vblk->vqs), GFP_KERNEL); |
347a5293 MH |
438 | if (!vblk->vqs) |
439 | return -ENOMEM; | |
6a27b656 | 440 | |
668866b6 ME |
441 | names = kmalloc_array(num_vqs, sizeof(*names), GFP_KERNEL); |
442 | callbacks = kmalloc_array(num_vqs, sizeof(*callbacks), GFP_KERNEL); | |
443 | vqs = kmalloc_array(num_vqs, sizeof(*vqs), GFP_KERNEL); | |
347a5293 MH |
444 | if (!names || !callbacks || !vqs) { |
445 | err = -ENOMEM; | |
446 | goto out; | |
447 | } | |
6abd6e5a | 448 | |
6a27b656 ML |
449 | for (i = 0; i < num_vqs; i++) { |
450 | callbacks[i] = virtblk_done; | |
451 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req.%d", i); | |
452 | names[i] = vblk->vqs[i].name; | |
453 | } | |
454 | ||
455 | /* Discover virtqueues and write information to configuration. */ | |
456 | err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names); | |
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 | ||
1cf7e9c6 JA |
590 | static struct blk_mq_ops virtio_mq_ops = { |
591 | .queue_rq = virtio_queue_rq, | |
5124c285 | 592 | .complete = virtblk_request_done, |
24d2f903 | 593 | .init_request = virtblk_init_request, |
1cf7e9c6 JA |
594 | }; |
595 | ||
24d2f903 CH |
596 | static unsigned int virtblk_queue_depth; |
597 | module_param_named(queue_depth, virtblk_queue_depth, uint, 0444); | |
1cf7e9c6 | 598 | |
8d85fce7 | 599 | static int virtblk_probe(struct virtio_device *vdev) |
e467cde2 RR |
600 | { |
601 | struct virtio_blk *vblk; | |
69740c8b | 602 | struct request_queue *q; |
5087a50e | 603 | int err, index; |
a98755c5 | 604 | |
e467cde2 | 605 | u64 cap; |
69740c8b CH |
606 | u32 v, blk_size, sg_elems, opt_io_size; |
607 | u16 min_io_size; | |
608 | u8 physical_block_exp, alignment_offset; | |
e467cde2 | 609 | |
a4379fd8 MT |
610 | if (!vdev->config->get) { |
611 | dev_err(&vdev->dev, "%s failure: config access disabled\n", | |
612 | __func__); | |
613 | return -EINVAL; | |
614 | } | |
615 | ||
5087a50e MT |
616 | err = ida_simple_get(&vd_index_ida, 0, minor_to_index(1 << MINORBITS), |
617 | GFP_KERNEL); | |
618 | if (err < 0) | |
619 | goto out; | |
620 | index = err; | |
4f3bf19c | 621 | |
0864b79a | 622 | /* We need to know how many segments before we allocate. */ |
855e0c52 RR |
623 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SEG_MAX, |
624 | struct virtio_blk_config, seg_max, | |
625 | &sg_elems); | |
a5b365a6 CH |
626 | |
627 | /* We need at least one SG element, whatever they say. */ | |
628 | if (err || !sg_elems) | |
0864b79a RR |
629 | sg_elems = 1; |
630 | ||
631 | /* We need an extra sg elements at head and tail. */ | |
632 | sg_elems += 2; | |
1cf7e9c6 | 633 | vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL); |
e467cde2 RR |
634 | if (!vblk) { |
635 | err = -ENOMEM; | |
5087a50e | 636 | goto out_free_index; |
e467cde2 RR |
637 | } |
638 | ||
e467cde2 | 639 | vblk->vdev = vdev; |
0864b79a | 640 | vblk->sg_elems = sg_elems; |
a98755c5 | 641 | |
7a7c924c | 642 | INIT_WORK(&vblk->config_work, virtblk_config_changed_work); |
e467cde2 | 643 | |
6abd6e5a AS |
644 | err = init_vq(vblk); |
645 | if (err) | |
e467cde2 | 646 | goto out_free_vblk; |
e467cde2 | 647 | |
e467cde2 | 648 | /* FIXME: How many partitions? How long is a piece of string? */ |
4f3bf19c | 649 | vblk->disk = alloc_disk(1 << PART_BITS); |
e467cde2 RR |
650 | if (!vblk->disk) { |
651 | err = -ENOMEM; | |
1cf7e9c6 | 652 | goto out_free_vq; |
e467cde2 RR |
653 | } |
654 | ||
fc4324b4 | 655 | /* Default queue sizing is to fill the ring. */ |
24d2f903 | 656 | if (!virtblk_queue_depth) { |
6a27b656 | 657 | virtblk_queue_depth = vblk->vqs[0].vq->num_free; |
fc4324b4 RR |
658 | /* ... but without indirect descs, we use 2 descs per req */ |
659 | if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC)) | |
24d2f903 | 660 | virtblk_queue_depth /= 2; |
fc4324b4 | 661 | } |
24d2f903 CH |
662 | |
663 | memset(&vblk->tag_set, 0, sizeof(vblk->tag_set)); | |
664 | vblk->tag_set.ops = &virtio_mq_ops; | |
24d2f903 CH |
665 | vblk->tag_set.queue_depth = virtblk_queue_depth; |
666 | vblk->tag_set.numa_node = NUMA_NO_NODE; | |
667 | vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; | |
668 | vblk->tag_set.cmd_size = | |
1cf7e9c6 JA |
669 | sizeof(struct virtblk_req) + |
670 | sizeof(struct scatterlist) * sg_elems; | |
24d2f903 | 671 | vblk->tag_set.driver_data = vblk; |
6a27b656 | 672 | vblk->tag_set.nr_hw_queues = vblk->num_vqs; |
1cf7e9c6 | 673 | |
24d2f903 CH |
674 | err = blk_mq_alloc_tag_set(&vblk->tag_set); |
675 | if (err) | |
676 | goto out_put_disk; | |
677 | ||
6bf6b0aa | 678 | q = blk_mq_init_queue(&vblk->tag_set); |
35b489d3 | 679 | if (IS_ERR(q)) { |
e467cde2 | 680 | err = -ENOMEM; |
24d2f903 | 681 | goto out_free_tags; |
e467cde2 | 682 | } |
6bf6b0aa | 683 | vblk->disk->queue = q; |
e467cde2 | 684 | |
69740c8b | 685 | q->queuedata = vblk; |
7d116b62 | 686 | |
c0aa3e09 | 687 | virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN); |
d50ed907 | 688 | |
e467cde2 | 689 | vblk->disk->major = major; |
d50ed907 | 690 | vblk->disk->first_minor = index_to_minor(index); |
e467cde2 RR |
691 | vblk->disk->private_data = vblk; |
692 | vblk->disk->fops = &virtblk_fops; | |
5fa3142d | 693 | vblk->disk->flags |= GENHD_FL_EXT_DEVT; |
5087a50e | 694 | vblk->index = index; |
4f3bf19c | 695 | |
02c42b7a | 696 | /* configure queue flush support */ |
cd5d5038 | 697 | virtblk_update_cache_mode(vdev); |
e467cde2 | 698 | |
3ef53609 CB |
699 | /* If disk is read-only in the host, the guest should obey */ |
700 | if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO)) | |
701 | set_disk_ro(vblk->disk, 1); | |
702 | ||
a586d4f6 | 703 | /* Host must always specify the capacity. */ |
855e0c52 | 704 | virtio_cread(vdev, struct virtio_blk_config, capacity, &cap); |
e467cde2 RR |
705 | |
706 | /* If capacity is too big, truncate with warning. */ | |
707 | if ((sector_t)cap != cap) { | |
708 | dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n", | |
709 | (unsigned long long)cap); | |
710 | cap = (sector_t)-1; | |
711 | } | |
712 | set_capacity(vblk->disk, cap); | |
713 | ||
0864b79a | 714 | /* We can handle whatever the host told us to handle. */ |
ee714f2d | 715 | blk_queue_max_segments(q, vblk->sg_elems-2); |
0864b79a | 716 | |
4eff3cae | 717 | /* No need to bounce any requests */ |
69740c8b | 718 | blk_queue_bounce_limit(q, BLK_BOUNCE_ANY); |
4eff3cae | 719 | |
4b7f7e20 | 720 | /* No real sector limit. */ |
ee714f2d | 721 | blk_queue_max_hw_sectors(q, -1U); |
4b7f7e20 | 722 | |
a586d4f6 RR |
723 | /* Host can optionally specify maximum segment size and number of |
724 | * segments. */ | |
855e0c52 RR |
725 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SIZE_MAX, |
726 | struct virtio_blk_config, size_max, &v); | |
e467cde2 | 727 | if (!err) |
69740c8b | 728 | blk_queue_max_segment_size(q, v); |
4b7f7e20 | 729 | else |
69740c8b | 730 | blk_queue_max_segment_size(q, -1U); |
e467cde2 | 731 | |
066f4d82 | 732 | /* Host can optionally specify the block size of the device */ |
855e0c52 RR |
733 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE, |
734 | struct virtio_blk_config, blk_size, | |
735 | &blk_size); | |
066f4d82 | 736 | if (!err) |
69740c8b CH |
737 | blk_queue_logical_block_size(q, blk_size); |
738 | else | |
739 | blk_size = queue_logical_block_size(q); | |
740 | ||
741 | /* Use topology information if available */ | |
855e0c52 RR |
742 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
743 | struct virtio_blk_config, physical_block_exp, | |
744 | &physical_block_exp); | |
69740c8b CH |
745 | if (!err && physical_block_exp) |
746 | blk_queue_physical_block_size(q, | |
747 | blk_size * (1 << physical_block_exp)); | |
748 | ||
855e0c52 RR |
749 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
750 | struct virtio_blk_config, alignment_offset, | |
751 | &alignment_offset); | |
69740c8b CH |
752 | if (!err && alignment_offset) |
753 | blk_queue_alignment_offset(q, blk_size * alignment_offset); | |
754 | ||
855e0c52 RR |
755 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
756 | struct virtio_blk_config, min_io_size, | |
757 | &min_io_size); | |
69740c8b CH |
758 | if (!err && min_io_size) |
759 | blk_queue_io_min(q, blk_size * min_io_size); | |
760 | ||
855e0c52 RR |
761 | err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY, |
762 | struct virtio_blk_config, opt_io_size, | |
763 | &opt_io_size); | |
69740c8b CH |
764 | if (!err && opt_io_size) |
765 | blk_queue_io_opt(q, blk_size * opt_io_size); | |
766 | ||
7a11370e MT |
767 | virtio_device_ready(vdev); |
768 | ||
0d52c756 | 769 | device_add_disk(&vdev->dev, vblk->disk); |
a5eb9e4f RH |
770 | err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial); |
771 | if (err) | |
772 | goto out_del_disk; | |
773 | ||
cd5d5038 PB |
774 | if (virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) |
775 | err = device_create_file(disk_to_dev(vblk->disk), | |
776 | &dev_attr_cache_type_rw); | |
777 | else | |
778 | err = device_create_file(disk_to_dev(vblk->disk), | |
779 | &dev_attr_cache_type_ro); | |
780 | if (err) | |
781 | goto out_del_disk; | |
e467cde2 RR |
782 | return 0; |
783 | ||
a5eb9e4f RH |
784 | out_del_disk: |
785 | del_gendisk(vblk->disk); | |
786 | blk_cleanup_queue(vblk->disk->queue); | |
24d2f903 CH |
787 | out_free_tags: |
788 | blk_mq_free_tag_set(&vblk->tag_set); | |
e467cde2 RR |
789 | out_put_disk: |
790 | put_disk(vblk->disk); | |
e467cde2 | 791 | out_free_vq: |
d2a7ddda | 792 | vdev->config->del_vqs(vdev); |
e467cde2 RR |
793 | out_free_vblk: |
794 | kfree(vblk); | |
5087a50e MT |
795 | out_free_index: |
796 | ida_simple_remove(&vd_index_ida, index); | |
e467cde2 RR |
797 | out: |
798 | return err; | |
799 | } | |
800 | ||
8d85fce7 | 801 | static void virtblk_remove(struct virtio_device *vdev) |
e467cde2 RR |
802 | { |
803 | struct virtio_blk *vblk = vdev->priv; | |
5087a50e | 804 | int index = vblk->index; |
f4953fe6 | 805 | int refc; |
e467cde2 | 806 | |
cc74f719 MT |
807 | /* Make sure no work handler is accessing the device. */ |
808 | flush_work(&vblk->config_work); | |
7a7c924c | 809 | |
02e2b124 | 810 | del_gendisk(vblk->disk); |
483001c7 | 811 | blk_cleanup_queue(vblk->disk->queue); |
02e2b124 | 812 | |
24d2f903 CH |
813 | blk_mq_free_tag_set(&vblk->tag_set); |
814 | ||
6e5aa7ef RR |
815 | /* Stop all the virtqueues. */ |
816 | vdev->config->reset(vdev); | |
817 | ||
f4953fe6 | 818 | refc = atomic_read(&disk_to_dev(vblk->disk)->kobj.kref.refcount); |
e467cde2 | 819 | put_disk(vblk->disk); |
d2a7ddda | 820 | vdev->config->del_vqs(vdev); |
6a27b656 | 821 | kfree(vblk->vqs); |
e467cde2 | 822 | kfree(vblk); |
f4953fe6 AG |
823 | |
824 | /* Only free device id if we don't have any users */ | |
825 | if (refc == 1) | |
826 | ida_simple_remove(&vd_index_ida, index); | |
e467cde2 RR |
827 | } |
828 | ||
89107000 | 829 | #ifdef CONFIG_PM_SLEEP |
f8fb5bc2 AS |
830 | static int virtblk_freeze(struct virtio_device *vdev) |
831 | { | |
832 | struct virtio_blk *vblk = vdev->priv; | |
833 | ||
834 | /* Ensure we don't receive any more interrupts */ | |
835 | vdev->config->reset(vdev); | |
836 | ||
cc74f719 | 837 | /* Make sure no work handler is accessing the device. */ |
f8fb5bc2 AS |
838 | flush_work(&vblk->config_work); |
839 | ||
1cf7e9c6 | 840 | blk_mq_stop_hw_queues(vblk->disk->queue); |
f8fb5bc2 AS |
841 | |
842 | vdev->config->del_vqs(vdev); | |
843 | return 0; | |
844 | } | |
845 | ||
846 | static int virtblk_restore(struct virtio_device *vdev) | |
847 | { | |
848 | struct virtio_blk *vblk = vdev->priv; | |
849 | int ret; | |
850 | ||
f8fb5bc2 | 851 | ret = init_vq(vdev->priv); |
6d62c37f MT |
852 | if (ret) |
853 | return ret; | |
854 | ||
855 | virtio_device_ready(vdev); | |
1cf7e9c6 | 856 | |
6d62c37f MT |
857 | blk_mq_start_stopped_hw_queues(vblk->disk->queue, true); |
858 | return 0; | |
f8fb5bc2 AS |
859 | } |
860 | #endif | |
861 | ||
47483e25 | 862 | static const struct virtio_device_id id_table[] = { |
e467cde2 RR |
863 | { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID }, |
864 | { 0 }, | |
865 | }; | |
866 | ||
19c1c5a6 | 867 | static unsigned int features_legacy[] = { |
02c42b7a | 868 | VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY, |
97b50a65 CH |
869 | VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, |
870 | #ifdef CONFIG_VIRTIO_BLK_SCSI | |
871 | VIRTIO_BLK_F_SCSI, | |
872 | #endif | |
592002f5 | 873 | VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE, |
6a27b656 | 874 | VIRTIO_BLK_F_MQ, |
19c1c5a6 MT |
875 | } |
876 | ; | |
877 | static unsigned int features[] = { | |
878 | VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY, | |
879 | VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, | |
592002f5 | 880 | VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE, |
19c1c5a6 | 881 | VIRTIO_BLK_F_MQ, |
c45a6816 RR |
882 | }; |
883 | ||
8d85fce7 | 884 | static struct virtio_driver virtio_blk = { |
19c1c5a6 MT |
885 | .feature_table = features, |
886 | .feature_table_size = ARRAY_SIZE(features), | |
887 | .feature_table_legacy = features_legacy, | |
888 | .feature_table_size_legacy = ARRAY_SIZE(features_legacy), | |
889 | .driver.name = KBUILD_MODNAME, | |
890 | .driver.owner = THIS_MODULE, | |
891 | .id_table = id_table, | |
892 | .probe = virtblk_probe, | |
893 | .remove = virtblk_remove, | |
894 | .config_changed = virtblk_config_changed, | |
89107000 | 895 | #ifdef CONFIG_PM_SLEEP |
19c1c5a6 MT |
896 | .freeze = virtblk_freeze, |
897 | .restore = virtblk_restore, | |
f8fb5bc2 | 898 | #endif |
e467cde2 RR |
899 | }; |
900 | ||
901 | static int __init init(void) | |
902 | { | |
7a7c924c CH |
903 | int error; |
904 | ||
905 | virtblk_wq = alloc_workqueue("virtio-blk", 0, 0); | |
906 | if (!virtblk_wq) | |
907 | return -ENOMEM; | |
908 | ||
4f3bf19c | 909 | major = register_blkdev(0, "virtblk"); |
7a7c924c CH |
910 | if (major < 0) { |
911 | error = major; | |
912 | goto out_destroy_workqueue; | |
913 | } | |
914 | ||
915 | error = register_virtio_driver(&virtio_blk); | |
916 | if (error) | |
917 | goto out_unregister_blkdev; | |
918 | return 0; | |
919 | ||
920 | out_unregister_blkdev: | |
921 | unregister_blkdev(major, "virtblk"); | |
922 | out_destroy_workqueue: | |
923 | destroy_workqueue(virtblk_wq); | |
924 | return error; | |
e467cde2 RR |
925 | } |
926 | ||
927 | static void __exit fini(void) | |
928 | { | |
929 | unregister_virtio_driver(&virtio_blk); | |
38f37b57 | 930 | unregister_blkdev(major, "virtblk"); |
7a7c924c | 931 | destroy_workqueue(virtblk_wq); |
e467cde2 RR |
932 | } |
933 | module_init(init); | |
934 | module_exit(fini); | |
935 | ||
936 | MODULE_DEVICE_TABLE(virtio, id_table); | |
937 | MODULE_DESCRIPTION("Virtio block driver"); | |
938 | MODULE_LICENSE("GPL"); |