blob: 74b88efde6ad408123de6a9b96ec37460195fe82 [file] [log] [blame]
Paolo Bonzini4fe74b12012-02-05 12:16:00 +01001/*
2 * Virtio SCSI HBA driver
3 *
4 * Copyright IBM Corp. 2010
5 * Copyright Red Hat, Inc. 2011
6 *
7 * Authors:
8 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
9 * Paolo Bonzini <pbonzini@redhat.com>
10 *
11 * This work is licensed under the terms of the GNU GPL, version 2 or later.
12 * See the COPYING file in the top-level directory.
13 *
14 */
15
Wanlong Gaoba06d1e2013-03-12 15:34:40 +103016#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
Paolo Bonzini4fe74b12012-02-05 12:16:00 +010018#include <linux/module.h>
19#include <linux/slab.h>
20#include <linux/mempool.h>
21#include <linux/virtio.h>
22#include <linux/virtio_ids.h>
23#include <linux/virtio_config.h>
24#include <linux/virtio_scsi.h>
Paolo Bonzini9141a4c2013-04-08 23:03:25 +093025#include <linux/cpu.h>
Paolo Bonzini4fe74b12012-02-05 12:16:00 +010026#include <scsi/scsi_host.h>
27#include <scsi/scsi_device.h>
28#include <scsi/scsi_cmnd.h>
29
30#define VIRTIO_SCSI_MEMPOOL_SZ 64
Cong Meng365a7152012-07-05 17:06:43 +080031#define VIRTIO_SCSI_EVENT_LEN 8
Paolo Bonzini9141a4c2013-04-08 23:03:25 +093032#define VIRTIO_SCSI_VQ_BASE 2
Paolo Bonzini4fe74b12012-02-05 12:16:00 +010033
34/* Command queue element */
35struct virtio_scsi_cmd {
36 struct scsi_cmnd *sc;
37 struct completion *comp;
38 union {
39 struct virtio_scsi_cmd_req cmd;
40 struct virtio_scsi_ctrl_tmf_req tmf;
41 struct virtio_scsi_ctrl_an_req an;
42 } req;
43 union {
44 struct virtio_scsi_cmd_resp cmd;
45 struct virtio_scsi_ctrl_tmf_resp tmf;
46 struct virtio_scsi_ctrl_an_resp an;
47 struct virtio_scsi_event evt;
48 } resp;
49} ____cacheline_aligned_in_smp;
50
Cong Meng365a7152012-07-05 17:06:43 +080051struct virtio_scsi_event_node {
52 struct virtio_scsi *vscsi;
53 struct virtio_scsi_event event;
54 struct work_struct work;
55};
56
Paolo Bonzini139fe452012-06-13 16:56:32 +020057struct virtio_scsi_vq {
58 /* Protects vq */
Paolo Bonzini4fe74b12012-02-05 12:16:00 +010059 spinlock_t vq_lock;
60
Paolo Bonzini139fe452012-06-13 16:56:32 +020061 struct virtqueue *vq;
62};
63
Paolo Bonzini9141a4c2013-04-08 23:03:25 +093064/*
65 * Per-target queue state.
66 *
67 * This struct holds the data needed by the queue steering policy. When a
68 * target is sent multiple requests, we need to drive them to the same queue so
69 * that FIFO processing order is kept. However, if a target was idle, we can
70 * choose a queue arbitrarily. In this case the queue is chosen according to
71 * the current VCPU, so the driver expects the number of request queues to be
72 * equal to the number of VCPUs. This makes it easy and fast to select the
73 * queue, and also lets the driver optimize the IRQ affinity for the virtqueues
74 * (each virtqueue's affinity is set to the CPU that "owns" the queue).
75 *
76 * An interesting effect of this policy is that only writes to req_vq need to
77 * take the tgt_lock. Read can be done outside the lock because:
78 *
79 * - writes of req_vq only occur when atomic_inc_return(&tgt->reqs) returns 1.
80 * In that case, no other CPU is reading req_vq: even if they were in
81 * virtscsi_queuecommand_multi, they would be spinning on tgt_lock.
82 *
83 * - reads of req_vq only occur when the target is not idle (reqs != 0).
84 * A CPU that enters virtscsi_queuecommand_multi will not modify req_vq.
85 *
86 * Similarly, decrements of reqs are never concurrent with writes of req_vq.
87 * Thus they can happen outside the tgt_lock, provided of course we make reqs
88 * an atomic_t.
89 */
Paolo Bonzini2bd37f02012-06-13 16:56:34 +020090struct virtio_scsi_target_state {
Paolo Bonzini9141a4c2013-04-08 23:03:25 +093091 /* This spinlock never held at the same time as vq_lock. */
Paolo Bonzini2bd37f02012-06-13 16:56:34 +020092 spinlock_t tgt_lock;
Paolo Bonzini9141a4c2013-04-08 23:03:25 +093093
94 /* Count of outstanding requests. */
95 atomic_t reqs;
96
97 /* Currently active virtqueue for requests sent to this target. */
98 struct virtio_scsi_vq *req_vq;
Paolo Bonzini2bd37f02012-06-13 16:56:34 +020099};
100
Paolo Bonzini139fe452012-06-13 16:56:32 +0200101/* Driver instance state */
102struct virtio_scsi {
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100103 struct virtio_device *vdev;
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200104
Cong Meng365a7152012-07-05 17:06:43 +0800105 /* Get some buffers ready for event vq */
106 struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930107
108 u32 num_queues;
109
110 /* If the affinity hint is set for virtqueues */
111 bool affinity_hint_set;
112
Wanlong Gao285e71e2013-04-08 23:05:49 +0930113 /* CPU hotplug notifier */
114 struct notifier_block nb;
115
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930116 struct virtio_scsi_vq ctrl_vq;
117 struct virtio_scsi_vq event_vq;
118 struct virtio_scsi_vq req_vqs[];
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100119};
120
121static struct kmem_cache *virtscsi_cmd_cache;
122static mempool_t *virtscsi_cmd_pool;
123
124static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev)
125{
126 return vdev->priv;
127}
128
129static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid)
130{
131 if (!resid)
132 return;
133
134 if (!scsi_bidi_cmnd(sc)) {
135 scsi_set_resid(sc, resid);
136 return;
137 }
138
139 scsi_in(sc)->resid = min(resid, scsi_in(sc)->length);
140 scsi_out(sc)->resid = resid - scsi_in(sc)->resid;
141}
142
143/**
144 * virtscsi_complete_cmd - finish a scsi_cmd and invoke scsi_done
145 *
146 * Called with vq_lock held.
147 */
Paolo Bonzini7f82b3c2013-04-08 23:01:38 +0930148static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf)
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100149{
150 struct virtio_scsi_cmd *cmd = buf;
151 struct scsi_cmnd *sc = cmd->sc;
152 struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd;
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930153 struct virtio_scsi_target_state *tgt =
154 scsi_target(sc->device)->hostdata;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100155
156 dev_dbg(&sc->device->sdev_gendev,
157 "cmd %p response %u status %#02x sense_len %u\n",
158 sc, resp->response, resp->status, resp->sense_len);
159
160 sc->result = resp->status;
161 virtscsi_compute_resid(sc, resp->resid);
162 switch (resp->response) {
163 case VIRTIO_SCSI_S_OK:
164 set_host_byte(sc, DID_OK);
165 break;
166 case VIRTIO_SCSI_S_OVERRUN:
167 set_host_byte(sc, DID_ERROR);
168 break;
169 case VIRTIO_SCSI_S_ABORTED:
170 set_host_byte(sc, DID_ABORT);
171 break;
172 case VIRTIO_SCSI_S_BAD_TARGET:
173 set_host_byte(sc, DID_BAD_TARGET);
174 break;
175 case VIRTIO_SCSI_S_RESET:
176 set_host_byte(sc, DID_RESET);
177 break;
178 case VIRTIO_SCSI_S_BUSY:
179 set_host_byte(sc, DID_BUS_BUSY);
180 break;
181 case VIRTIO_SCSI_S_TRANSPORT_FAILURE:
182 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
183 break;
184 case VIRTIO_SCSI_S_TARGET_FAILURE:
185 set_host_byte(sc, DID_TARGET_FAILURE);
186 break;
187 case VIRTIO_SCSI_S_NEXUS_FAILURE:
188 set_host_byte(sc, DID_NEXUS_FAILURE);
189 break;
190 default:
191 scmd_printk(KERN_WARNING, sc, "Unknown response %d",
192 resp->response);
193 /* fall through */
194 case VIRTIO_SCSI_S_FAILURE:
195 set_host_byte(sc, DID_ERROR);
196 break;
197 }
198
199 WARN_ON(resp->sense_len > VIRTIO_SCSI_SENSE_SIZE);
200 if (sc->sense_buffer) {
201 memcpy(sc->sense_buffer, resp->sense,
202 min_t(u32, resp->sense_len, VIRTIO_SCSI_SENSE_SIZE));
203 if (resp->sense_len)
204 set_driver_byte(sc, DRIVER_SENSE);
205 }
206
207 mempool_free(cmd, virtscsi_cmd_pool);
208 sc->scsi_done(sc);
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930209
210 atomic_dec(&tgt->reqs);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100211}
212
Paolo Bonzini10f34f62013-04-08 23:02:07 +0930213static void virtscsi_vq_done(struct virtio_scsi *vscsi,
214 struct virtio_scsi_vq *virtscsi_vq,
Paolo Bonzini7f82b3c2013-04-08 23:01:38 +0930215 void (*fn)(struct virtio_scsi *vscsi, void *buf))
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100216{
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100217 void *buf;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100218 unsigned int len;
Paolo Bonzini10f34f62013-04-08 23:02:07 +0930219 unsigned long flags;
220 struct virtqueue *vq = virtscsi_vq->vq;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100221
Paolo Bonzini10f34f62013-04-08 23:02:07 +0930222 spin_lock_irqsave(&virtscsi_vq->vq_lock, flags);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100223 do {
224 virtqueue_disable_cb(vq);
225 while ((buf = virtqueue_get_buf(vq, &len)) != NULL)
Paolo Bonzini7f82b3c2013-04-08 23:01:38 +0930226 fn(vscsi, buf);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100227 } while (!virtqueue_enable_cb(vq));
Paolo Bonzini10f34f62013-04-08 23:02:07 +0930228 spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100229}
230
231static void virtscsi_req_done(struct virtqueue *vq)
232{
Paolo Bonzini139fe452012-06-13 16:56:32 +0200233 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
234 struct virtio_scsi *vscsi = shost_priv(sh);
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930235 int index = vq->index - VIRTIO_SCSI_VQ_BASE;
236 struct virtio_scsi_vq *req_vq = &vscsi->req_vqs[index];
Paolo Bonzini139fe452012-06-13 16:56:32 +0200237
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930238 /*
239 * Read req_vq before decrementing the reqs field in
240 * virtscsi_complete_cmd.
241 *
242 * With barriers:
243 *
244 * CPU #0 virtscsi_queuecommand_multi (CPU #1)
245 * ------------------------------------------------------------
246 * lock vq_lock
247 * read req_vq
248 * read reqs (reqs = 1)
249 * write reqs (reqs = 0)
250 * increment reqs (reqs = 1)
251 * write req_vq
252 *
253 * Possible reordering without barriers:
254 *
255 * CPU #0 virtscsi_queuecommand_multi (CPU #1)
256 * ------------------------------------------------------------
257 * lock vq_lock
258 * read reqs (reqs = 1)
259 * write reqs (reqs = 0)
260 * increment reqs (reqs = 1)
261 * write req_vq
262 * read (wrong) req_vq
263 *
264 * We do not need a full smp_rmb, because req_vq is required to get
265 * to tgt->reqs: tgt is &vscsi->tgt[sc->device->id], where sc is stored
266 * in the virtqueue as the user token.
267 */
268 smp_read_barrier_depends();
269
270 virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100271};
272
Paolo Bonzini7f82b3c2013-04-08 23:01:38 +0930273static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf)
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100274{
275 struct virtio_scsi_cmd *cmd = buf;
276
277 if (cmd->comp)
278 complete_all(cmd->comp);
Paolo Bonzinie4594bb2012-05-04 12:32:04 +0200279 else
280 mempool_free(cmd, virtscsi_cmd_pool);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100281}
282
283static void virtscsi_ctrl_done(struct virtqueue *vq)
284{
Paolo Bonzini139fe452012-06-13 16:56:32 +0200285 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
286 struct virtio_scsi *vscsi = shost_priv(sh);
Paolo Bonzini139fe452012-06-13 16:56:32 +0200287
Paolo Bonzini10f34f62013-04-08 23:02:07 +0930288 virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100289};
290
Cong Meng365a7152012-07-05 17:06:43 +0800291static int virtscsi_kick_event(struct virtio_scsi *vscsi,
292 struct virtio_scsi_event_node *event_node)
293{
Rusty Russell4614e512012-10-16 23:56:16 +1030294 int err;
Cong Meng365a7152012-07-05 17:06:43 +0800295 struct scatterlist sg;
296 unsigned long flags;
297
Richard W.M. Jones2e9c9df2012-10-02 17:25:46 +0200298 sg_init_one(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
Cong Meng365a7152012-07-05 17:06:43 +0800299
300 spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
301
Rusty Russellbf958292013-03-20 15:44:28 +1030302 err = virtqueue_add_inbuf(vscsi->event_vq.vq, &sg, 1, event_node,
303 GFP_ATOMIC);
Rusty Russell4614e512012-10-16 23:56:16 +1030304 if (!err)
Cong Meng365a7152012-07-05 17:06:43 +0800305 virtqueue_kick(vscsi->event_vq.vq);
306
307 spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags);
308
Rusty Russell4614e512012-10-16 23:56:16 +1030309 return err;
Cong Meng365a7152012-07-05 17:06:43 +0800310}
311
312static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
313{
314 int i;
315
316 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
317 vscsi->event_list[i].vscsi = vscsi;
318 virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
319 }
320
321 return 0;
322}
323
324static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi)
325{
326 int i;
327
328 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++)
329 cancel_work_sync(&vscsi->event_list[i].work);
330}
331
332static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930333 struct virtio_scsi_event *event)
Cong Meng365a7152012-07-05 17:06:43 +0800334{
335 struct scsi_device *sdev;
336 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
337 unsigned int target = event->lun[1];
338 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
339
340 switch (event->reason) {
341 case VIRTIO_SCSI_EVT_RESET_RESCAN:
342 scsi_add_device(shost, 0, target, lun);
343 break;
344 case VIRTIO_SCSI_EVT_RESET_REMOVED:
345 sdev = scsi_device_lookup(shost, 0, target, lun);
346 if (sdev) {
347 scsi_remove_device(sdev);
348 scsi_device_put(sdev);
349 } else {
350 pr_err("SCSI device %d 0 %d %d not found\n",
351 shost->host_no, target, lun);
352 }
353 break;
354 default:
355 pr_info("Unsupport virtio scsi event reason %x\n", event->reason);
356 }
357}
358
Paolo Bonzini865b58c2012-10-02 17:25:48 +0200359static void virtscsi_handle_param_change(struct virtio_scsi *vscsi,
360 struct virtio_scsi_event *event)
361{
362 struct scsi_device *sdev;
363 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
364 unsigned int target = event->lun[1];
365 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
366 u8 asc = event->reason & 255;
367 u8 ascq = event->reason >> 8;
368
369 sdev = scsi_device_lookup(shost, 0, target, lun);
370 if (!sdev) {
371 pr_err("SCSI device %d 0 %d %d not found\n",
372 shost->host_no, target, lun);
373 return;
374 }
375
376 /* Handle "Parameters changed", "Mode parameters changed", and
377 "Capacity data has changed". */
378 if (asc == 0x2a && (ascq == 0x00 || ascq == 0x01 || ascq == 0x09))
379 scsi_rescan_device(&sdev->sdev_gendev);
380
381 scsi_device_put(sdev);
382}
383
Cong Meng365a7152012-07-05 17:06:43 +0800384static void virtscsi_handle_event(struct work_struct *work)
385{
386 struct virtio_scsi_event_node *event_node =
387 container_of(work, struct virtio_scsi_event_node, work);
388 struct virtio_scsi *vscsi = event_node->vscsi;
389 struct virtio_scsi_event *event = &event_node->event;
390
391 if (event->event & VIRTIO_SCSI_T_EVENTS_MISSED) {
392 event->event &= ~VIRTIO_SCSI_T_EVENTS_MISSED;
393 scsi_scan_host(virtio_scsi_host(vscsi->vdev));
394 }
395
396 switch (event->event) {
397 case VIRTIO_SCSI_T_NO_EVENT:
398 break;
399 case VIRTIO_SCSI_T_TRANSPORT_RESET:
400 virtscsi_handle_transport_reset(vscsi, event);
401 break;
Paolo Bonzini865b58c2012-10-02 17:25:48 +0200402 case VIRTIO_SCSI_T_PARAM_CHANGE:
403 virtscsi_handle_param_change(vscsi, event);
404 break;
Cong Meng365a7152012-07-05 17:06:43 +0800405 default:
406 pr_err("Unsupport virtio scsi event %x\n", event->event);
407 }
408 virtscsi_kick_event(vscsi, event_node);
409}
410
Paolo Bonzini7f82b3c2013-04-08 23:01:38 +0930411static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf)
Cong Meng365a7152012-07-05 17:06:43 +0800412{
413 struct virtio_scsi_event_node *event_node = buf;
414
415 INIT_WORK(&event_node->work, virtscsi_handle_event);
416 schedule_work(&event_node->work);
417}
418
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100419static void virtscsi_event_done(struct virtqueue *vq)
420{
Paolo Bonzini139fe452012-06-13 16:56:32 +0200421 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
422 struct virtio_scsi *vscsi = shost_priv(sh);
Paolo Bonzini139fe452012-06-13 16:56:32 +0200423
Paolo Bonzini10f34f62013-04-08 23:02:07 +0930424 virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100425};
426
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100427/**
Wanlong Gao682993b2013-03-20 15:44:28 +1030428 * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue
429 * @vq : the struct virtqueue we're talking about
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100430 * @cmd : command structure
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100431 * @req_size : size of the request buffer
432 * @resp_size : size of the response buffer
Wanlong Gao682993b2013-03-20 15:44:28 +1030433 * @gfp : flags to use for memory allocations
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100434 */
Wanlong Gao682993b2013-03-20 15:44:28 +1030435static int virtscsi_add_cmd(struct virtqueue *vq,
436 struct virtio_scsi_cmd *cmd,
437 size_t req_size, size_t resp_size, gfp_t gfp)
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100438{
439 struct scsi_cmnd *sc = cmd->sc;
Wanlong Gao682993b2013-03-20 15:44:28 +1030440 struct scatterlist *sgs[4], req, resp;
441 struct sg_table *out, *in;
442 unsigned out_num = 0, in_num = 0;
443
444 out = in = NULL;
445
446 if (sc && sc->sc_data_direction != DMA_NONE) {
447 if (sc->sc_data_direction != DMA_FROM_DEVICE)
448 out = &scsi_out(sc)->table;
449 if (sc->sc_data_direction != DMA_TO_DEVICE)
450 in = &scsi_in(sc)->table;
451 }
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100452
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100453 /* Request header. */
Wanlong Gao682993b2013-03-20 15:44:28 +1030454 sg_init_one(&req, &cmd->req, req_size);
455 sgs[out_num++] = &req;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100456
457 /* Data-out buffer. */
Wanlong Gao682993b2013-03-20 15:44:28 +1030458 if (out)
459 sgs[out_num++] = out->sgl;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100460
461 /* Response header. */
Wanlong Gao682993b2013-03-20 15:44:28 +1030462 sg_init_one(&resp, &cmd->resp, resp_size);
463 sgs[out_num + in_num++] = &resp;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100464
465 /* Data-in buffer */
Wanlong Gao682993b2013-03-20 15:44:28 +1030466 if (in)
467 sgs[out_num + in_num++] = in->sgl;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100468
Wanlong Gao682993b2013-03-20 15:44:28 +1030469 return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, gfp);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100470}
471
Wanlong Gao682993b2013-03-20 15:44:28 +1030472static int virtscsi_kick_cmd(struct virtio_scsi_vq *vq,
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100473 struct virtio_scsi_cmd *cmd,
474 size_t req_size, size_t resp_size, gfp_t gfp)
475{
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100476 unsigned long flags;
Rusty Russell4614e512012-10-16 23:56:16 +1030477 int err;
478 bool needs_kick = false;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100479
Wanlong Gao682993b2013-03-20 15:44:28 +1030480 spin_lock_irqsave(&vq->vq_lock, flags);
481 err = virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size, gfp);
Rusty Russell4614e512012-10-16 23:56:16 +1030482 if (!err)
483 needs_kick = virtqueue_kick_prepare(vq->vq);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100484
Paolo Bonzinibce750b2012-06-13 16:56:33 +0200485 spin_unlock_irqrestore(&vq->vq_lock, flags);
Paolo Bonzini139fe452012-06-13 16:56:32 +0200486
Rusty Russell4614e512012-10-16 23:56:16 +1030487 if (needs_kick)
Paolo Bonzini139fe452012-06-13 16:56:32 +0200488 virtqueue_notify(vq->vq);
Rusty Russell4614e512012-10-16 23:56:16 +1030489 return err;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100490}
491
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930492static int virtscsi_queuecommand(struct virtio_scsi *vscsi,
493 struct virtio_scsi_vq *req_vq,
494 struct scsi_cmnd *sc)
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100495{
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100496 struct virtio_scsi_cmd *cmd;
497 int ret;
498
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200499 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
500 BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize);
501
502 /* TODO: check feature bit and fail if unsupported? */
503 BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL);
504
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100505 dev_dbg(&sc->device->sdev_gendev,
506 "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]);
507
508 ret = SCSI_MLQUEUE_HOST_BUSY;
509 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_ATOMIC);
510 if (!cmd)
511 goto out;
512
513 memset(cmd, 0, sizeof(*cmd));
514 cmd->sc = sc;
515 cmd->req.cmd = (struct virtio_scsi_cmd_req){
516 .lun[0] = 1,
517 .lun[1] = sc->device->id,
518 .lun[2] = (sc->device->lun >> 8) | 0x40,
519 .lun[3] = sc->device->lun & 0xff,
520 .tag = (unsigned long)sc,
521 .task_attr = VIRTIO_SCSI_S_SIMPLE,
522 .prio = 0,
523 .crn = 0,
524 };
525
526 BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE);
527 memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len);
528
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930529 if (virtscsi_kick_cmd(req_vq, cmd,
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100530 sizeof cmd->req.cmd, sizeof cmd->resp.cmd,
Rusty Russell4614e512012-10-16 23:56:16 +1030531 GFP_ATOMIC) == 0)
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100532 ret = 0;
Eric Northupb56d1002012-11-08 01:55:50 -0800533 else
534 mempool_free(cmd, virtscsi_cmd_pool);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100535
536out:
537 return ret;
538}
539
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930540static int virtscsi_queuecommand_single(struct Scsi_Host *sh,
541 struct scsi_cmnd *sc)
542{
543 struct virtio_scsi *vscsi = shost_priv(sh);
544 struct virtio_scsi_target_state *tgt =
545 scsi_target(sc->device)->hostdata;
546
547 atomic_inc(&tgt->reqs);
548 return virtscsi_queuecommand(vscsi, &vscsi->req_vqs[0], sc);
549}
550
551static struct virtio_scsi_vq *virtscsi_pick_vq(struct virtio_scsi *vscsi,
552 struct virtio_scsi_target_state *tgt)
553{
554 struct virtio_scsi_vq *vq;
555 unsigned long flags;
556 u32 queue_num;
557
558 spin_lock_irqsave(&tgt->tgt_lock, flags);
559
560 /*
561 * The memory barrier after atomic_inc_return matches
562 * the smp_read_barrier_depends() in virtscsi_req_done.
563 */
564 if (atomic_inc_return(&tgt->reqs) > 1)
565 vq = ACCESS_ONCE(tgt->req_vq);
566 else {
567 queue_num = smp_processor_id();
568 while (unlikely(queue_num >= vscsi->num_queues))
569 queue_num -= vscsi->num_queues;
570
571 tgt->req_vq = vq = &vscsi->req_vqs[queue_num];
572 }
573
574 spin_unlock_irqrestore(&tgt->tgt_lock, flags);
575 return vq;
576}
577
578static int virtscsi_queuecommand_multi(struct Scsi_Host *sh,
579 struct scsi_cmnd *sc)
580{
581 struct virtio_scsi *vscsi = shost_priv(sh);
582 struct virtio_scsi_target_state *tgt =
583 scsi_target(sc->device)->hostdata;
584 struct virtio_scsi_vq *req_vq = virtscsi_pick_vq(vscsi, tgt);
585
586 return virtscsi_queuecommand(vscsi, req_vq, sc);
587}
588
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100589static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
590{
591 DECLARE_COMPLETION_ONSTACK(comp);
Paolo Bonzinie4594bb2012-05-04 12:32:04 +0200592 int ret = FAILED;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100593
594 cmd->comp = &comp;
Wanlong Gao682993b2013-03-20 15:44:28 +1030595 if (virtscsi_kick_cmd(&vscsi->ctrl_vq, cmd,
Paolo Bonzinie4594bb2012-05-04 12:32:04 +0200596 sizeof cmd->req.tmf, sizeof cmd->resp.tmf,
597 GFP_NOIO) < 0)
598 goto out;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100599
600 wait_for_completion(&comp);
Paolo Bonzinie4594bb2012-05-04 12:32:04 +0200601 if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
602 cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
603 ret = SUCCESS;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100604
Paolo Bonzinie4594bb2012-05-04 12:32:04 +0200605out:
606 mempool_free(cmd, virtscsi_cmd_pool);
607 return ret;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100608}
609
610static int virtscsi_device_reset(struct scsi_cmnd *sc)
611{
612 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
613 struct virtio_scsi_cmd *cmd;
614
615 sdev_printk(KERN_INFO, sc->device, "device reset\n");
616 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
617 if (!cmd)
618 return FAILED;
619
620 memset(cmd, 0, sizeof(*cmd));
621 cmd->sc = sc;
622 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
623 .type = VIRTIO_SCSI_T_TMF,
624 .subtype = VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET,
625 .lun[0] = 1,
626 .lun[1] = sc->device->id,
627 .lun[2] = (sc->device->lun >> 8) | 0x40,
628 .lun[3] = sc->device->lun & 0xff,
629 };
630 return virtscsi_tmf(vscsi, cmd);
631}
632
633static int virtscsi_abort(struct scsi_cmnd *sc)
634{
635 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
636 struct virtio_scsi_cmd *cmd;
637
638 scmd_printk(KERN_INFO, sc, "abort\n");
639 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
640 if (!cmd)
641 return FAILED;
642
643 memset(cmd, 0, sizeof(*cmd));
644 cmd->sc = sc;
645 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
646 .type = VIRTIO_SCSI_T_TMF,
647 .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK,
648 .lun[0] = 1,
649 .lun[1] = sc->device->id,
650 .lun[2] = (sc->device->lun >> 8) | 0x40,
651 .lun[3] = sc->device->lun & 0xff,
652 .tag = (unsigned long)sc,
653 };
654 return virtscsi_tmf(vscsi, cmd);
655}
656
Wanlong Gao5c370192013-04-08 23:01:16 +0930657static int virtscsi_target_alloc(struct scsi_target *starget)
658{
659 struct virtio_scsi_target_state *tgt =
660 kmalloc(sizeof(*tgt), GFP_KERNEL);
661 if (!tgt)
662 return -ENOMEM;
663
664 spin_lock_init(&tgt->tgt_lock);
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930665 atomic_set(&tgt->reqs, 0);
666 tgt->req_vq = NULL;
Wanlong Gao5c370192013-04-08 23:01:16 +0930667
668 starget->hostdata = tgt;
669 return 0;
670}
671
672static void virtscsi_target_destroy(struct scsi_target *starget)
673{
674 struct virtio_scsi_target_state *tgt = starget->hostdata;
675 kfree(tgt);
676}
677
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930678static struct scsi_host_template virtscsi_host_template_single = {
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100679 .module = THIS_MODULE,
680 .name = "Virtio SCSI HBA",
681 .proc_name = "virtio_scsi",
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100682 .this_id = -1,
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930683 .queuecommand = virtscsi_queuecommand_single,
684 .eh_abort_handler = virtscsi_abort,
685 .eh_device_reset_handler = virtscsi_device_reset,
686
687 .can_queue = 1024,
688 .dma_boundary = UINT_MAX,
689 .use_clustering = ENABLE_CLUSTERING,
690 .target_alloc = virtscsi_target_alloc,
691 .target_destroy = virtscsi_target_destroy,
692};
693
694static struct scsi_host_template virtscsi_host_template_multi = {
695 .module = THIS_MODULE,
696 .name = "Virtio SCSI HBA",
697 .proc_name = "virtio_scsi",
698 .this_id = -1,
699 .queuecommand = virtscsi_queuecommand_multi,
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100700 .eh_abort_handler = virtscsi_abort,
701 .eh_device_reset_handler = virtscsi_device_reset,
702
703 .can_queue = 1024,
704 .dma_boundary = UINT_MAX,
705 .use_clustering = ENABLE_CLUSTERING,
Wanlong Gao5c370192013-04-08 23:01:16 +0930706 .target_alloc = virtscsi_target_alloc,
707 .target_destroy = virtscsi_target_destroy,
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100708};
709
710#define virtscsi_config_get(vdev, fld) \
711 ({ \
712 typeof(((struct virtio_scsi_config *)0)->fld) __val; \
713 vdev->config->get(vdev, \
714 offsetof(struct virtio_scsi_config, fld), \
715 &__val, sizeof(__val)); \
716 __val; \
717 })
718
719#define virtscsi_config_set(vdev, fld, val) \
720 (void)({ \
721 typeof(((struct virtio_scsi_config *)0)->fld) __val = (val); \
722 vdev->config->set(vdev, \
723 offsetof(struct virtio_scsi_config, fld), \
724 &__val, sizeof(__val)); \
725 })
726
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930727static void __virtscsi_set_affinity(struct virtio_scsi *vscsi, bool affinity)
728{
729 int i;
730 int cpu;
731
732 /* In multiqueue mode, when the number of cpu is equal
733 * to the number of request queues, we let the qeueues
734 * to be private to one cpu by setting the affinity hint
735 * to eliminate the contention.
736 */
737 if ((vscsi->num_queues == 1 ||
738 vscsi->num_queues != num_online_cpus()) && affinity) {
739 if (vscsi->affinity_hint_set)
740 affinity = false;
741 else
742 return;
743 }
744
745 if (affinity) {
746 i = 0;
747 for_each_online_cpu(cpu) {
748 virtqueue_set_affinity(vscsi->req_vqs[i].vq, cpu);
749 i++;
750 }
751
752 vscsi->affinity_hint_set = true;
753 } else {
Asias Heaa52aee2013-08-01 11:07:18 +0930754 for (i = 0; i < vscsi->num_queues; i++)
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930755 virtqueue_set_affinity(vscsi->req_vqs[i].vq, -1);
756
757 vscsi->affinity_hint_set = false;
758 }
759}
760
761static void virtscsi_set_affinity(struct virtio_scsi *vscsi, bool affinity)
762{
763 get_online_cpus();
764 __virtscsi_set_affinity(vscsi, affinity);
765 put_online_cpus();
766}
767
Wanlong Gao285e71e2013-04-08 23:05:49 +0930768static int virtscsi_cpu_callback(struct notifier_block *nfb,
769 unsigned long action, void *hcpu)
770{
771 struct virtio_scsi *vscsi = container_of(nfb, struct virtio_scsi, nb);
772 switch(action) {
773 case CPU_ONLINE:
774 case CPU_ONLINE_FROZEN:
775 case CPU_DEAD:
776 case CPU_DEAD_FROZEN:
777 __virtscsi_set_affinity(vscsi, true);
778 break;
779 default:
780 break;
781 }
782 return NOTIFY_OK;
783}
784
Paolo Bonzini139fe452012-06-13 16:56:32 +0200785static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
786 struct virtqueue *vq)
787{
788 spin_lock_init(&virtscsi_vq->vq_lock);
789 virtscsi_vq->vq = vq;
790}
791
Nicholas Bellinger59057fb2012-07-11 21:22:16 +0000792static void virtscsi_scan(struct virtio_device *vdev)
793{
794 struct Scsi_Host *shost = (struct Scsi_Host *)vdev->priv;
795
796 scsi_scan_host(shost);
797}
798
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200799static void virtscsi_remove_vqs(struct virtio_device *vdev)
800{
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930801 struct Scsi_Host *sh = virtio_scsi_host(vdev);
802 struct virtio_scsi *vscsi = shost_priv(sh);
803
804 virtscsi_set_affinity(vscsi, false);
805
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200806 /* Stop all the virtqueues. */
807 vdev->config->reset(vdev);
808
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200809 vdev->config->del_vqs(vdev);
810}
811
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100812static int virtscsi_init(struct virtio_device *vdev,
Wanlong Gao5c370192013-04-08 23:01:16 +0930813 struct virtio_scsi *vscsi)
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100814{
815 int err;
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930816 u32 i;
817 u32 num_vqs;
818 vq_callback_t **callbacks;
819 const char **names;
820 struct virtqueue **vqs;
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200821
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930822 num_vqs = vscsi->num_queues + VIRTIO_SCSI_VQ_BASE;
823 vqs = kmalloc(num_vqs * sizeof(struct virtqueue *), GFP_KERNEL);
824 callbacks = kmalloc(num_vqs * sizeof(vq_callback_t *), GFP_KERNEL);
825 names = kmalloc(num_vqs * sizeof(char *), GFP_KERNEL);
826
827 if (!callbacks || !vqs || !names) {
828 err = -ENOMEM;
829 goto out;
830 }
831
832 callbacks[0] = virtscsi_ctrl_done;
833 callbacks[1] = virtscsi_event_done;
834 names[0] = "control";
835 names[1] = "event";
836 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++) {
837 callbacks[i] = virtscsi_req_done;
838 names[i] = "request";
839 }
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100840
841 /* Discover virtqueues and write information to configuration. */
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930842 err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100843 if (err)
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930844 goto out;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100845
Paolo Bonzini139fe452012-06-13 16:56:32 +0200846 virtscsi_init_vq(&vscsi->ctrl_vq, vqs[0]);
847 virtscsi_init_vq(&vscsi->event_vq, vqs[1]);
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930848 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++)
849 virtscsi_init_vq(&vscsi->req_vqs[i - VIRTIO_SCSI_VQ_BASE],
850 vqs[i]);
851
852 virtscsi_set_affinity(vscsi, true);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100853
854 virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
855 virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200856
Cong Meng365a7152012-07-05 17:06:43 +0800857 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
858 virtscsi_kick_event_all(vscsi);
859
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930860 err = 0;
861
862out:
863 kfree(names);
864 kfree(callbacks);
865 kfree(vqs);
866 if (err)
867 virtscsi_remove_vqs(vdev);
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200868 return err;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100869}
870
Greg Kroah-Hartman6f039792012-12-21 13:08:55 -0800871static int virtscsi_probe(struct virtio_device *vdev)
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100872{
873 struct Scsi_Host *shost;
874 struct virtio_scsi *vscsi;
875 int err;
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200876 u32 sg_elems, num_targets;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100877 u32 cmd_per_lun;
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930878 u32 num_queues;
879 struct scsi_host_template *hostt;
880
881 /* We need to know how many queues before we allocate. */
882 num_queues = virtscsi_config_get(vdev, num_queues) ? : 1;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100883
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200884 num_targets = virtscsi_config_get(vdev, max_target) + 1;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100885
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930886 if (num_queues == 1)
887 hostt = &virtscsi_host_template_single;
888 else
889 hostt = &virtscsi_host_template_multi;
890
891 shost = scsi_host_alloc(hostt,
892 sizeof(*vscsi) + sizeof(vscsi->req_vqs[0]) * num_queues);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100893 if (!shost)
894 return -ENOMEM;
895
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200896 sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100897 shost->sg_tablesize = sg_elems;
898 vscsi = shost_priv(shost);
899 vscsi->vdev = vdev;
Paolo Bonzini9141a4c2013-04-08 23:03:25 +0930900 vscsi->num_queues = num_queues;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100901 vdev->priv = shost;
902
Wanlong Gao5c370192013-04-08 23:01:16 +0930903 err = virtscsi_init(vdev, vscsi);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100904 if (err)
905 goto virtscsi_init_failed;
906
Wanlong Gao285e71e2013-04-08 23:05:49 +0930907 vscsi->nb.notifier_call = &virtscsi_cpu_callback;
908 err = register_hotcpu_notifier(&vscsi->nb);
909 if (err) {
910 pr_err("registering cpu notifier failed\n");
911 goto scsi_add_host_failed;
912 }
913
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100914 cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
915 shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
916 shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
Paolo Bonzini9da5f5a2012-10-02 17:25:47 +0200917
918 /* LUNs > 256 are reported with format 1, so they go in the range
919 * 16640-32767.
920 */
921 shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1 + 0x4000;
Paolo Bonzini2bd37f02012-06-13 16:56:34 +0200922 shost->max_id = num_targets;
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100923 shost->max_channel = 0;
924 shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE;
925 err = scsi_add_host(shost, &vdev->dev);
926 if (err)
927 goto scsi_add_host_failed;
Nicholas Bellinger59057fb2012-07-11 21:22:16 +0000928 /*
929 * scsi_scan_host() happens in virtscsi_scan() via virtio_driver->scan()
930 * after VIRTIO_CONFIG_S_DRIVER_OK has been set..
931 */
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100932 return 0;
933
934scsi_add_host_failed:
935 vdev->config->del_vqs(vdev);
936virtscsi_init_failed:
937 scsi_host_put(shost);
938 return err;
939}
940
Greg Kroah-Hartman6f039792012-12-21 13:08:55 -0800941static void virtscsi_remove(struct virtio_device *vdev)
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100942{
943 struct Scsi_Host *shost = virtio_scsi_host(vdev);
Cong Meng365a7152012-07-05 17:06:43 +0800944 struct virtio_scsi *vscsi = shost_priv(shost);
945
946 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
947 virtscsi_cancel_event_work(vscsi);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100948
949 scsi_remove_host(shost);
950
Wanlong Gao285e71e2013-04-08 23:05:49 +0930951 unregister_hotcpu_notifier(&vscsi->nb);
952
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100953 virtscsi_remove_vqs(vdev);
954 scsi_host_put(shost);
955}
956
957#ifdef CONFIG_PM
958static int virtscsi_freeze(struct virtio_device *vdev)
959{
960 virtscsi_remove_vqs(vdev);
961 return 0;
962}
963
964static int virtscsi_restore(struct virtio_device *vdev)
965{
966 struct Scsi_Host *sh = virtio_scsi_host(vdev);
967 struct virtio_scsi *vscsi = shost_priv(sh);
968
Wanlong Gao5c370192013-04-08 23:01:16 +0930969 return virtscsi_init(vdev, vscsi);
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100970}
971#endif
972
973static struct virtio_device_id id_table[] = {
974 { VIRTIO_ID_SCSI, VIRTIO_DEV_ANY_ID },
975 { 0 },
976};
977
Cong Meng365a7152012-07-05 17:06:43 +0800978static unsigned int features[] = {
Paolo Bonzini865b58c2012-10-02 17:25:48 +0200979 VIRTIO_SCSI_F_HOTPLUG,
980 VIRTIO_SCSI_F_CHANGE,
Cong Meng365a7152012-07-05 17:06:43 +0800981};
982
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100983static struct virtio_driver virtio_scsi_driver = {
Cong Meng365a7152012-07-05 17:06:43 +0800984 .feature_table = features,
985 .feature_table_size = ARRAY_SIZE(features),
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100986 .driver.name = KBUILD_MODNAME,
987 .driver.owner = THIS_MODULE,
988 .id_table = id_table,
989 .probe = virtscsi_probe,
Nicholas Bellinger59057fb2012-07-11 21:22:16 +0000990 .scan = virtscsi_scan,
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100991#ifdef CONFIG_PM
992 .freeze = virtscsi_freeze,
993 .restore = virtscsi_restore,
994#endif
Greg Kroah-Hartman6f039792012-12-21 13:08:55 -0800995 .remove = virtscsi_remove,
Paolo Bonzini4fe74b12012-02-05 12:16:00 +0100996};
997
998static int __init init(void)
999{
1000 int ret = -ENOMEM;
1001
1002 virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0);
1003 if (!virtscsi_cmd_cache) {
Wanlong Gaoba06d1e2013-03-12 15:34:40 +10301004 pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n");
Paolo Bonzini4fe74b12012-02-05 12:16:00 +01001005 goto error;
1006 }
1007
1008
1009 virtscsi_cmd_pool =
1010 mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ,
1011 virtscsi_cmd_cache);
1012 if (!virtscsi_cmd_pool) {
Wanlong Gaoba06d1e2013-03-12 15:34:40 +10301013 pr_err("mempool_create() for virtscsi_cmd_pool failed\n");
Paolo Bonzini4fe74b12012-02-05 12:16:00 +01001014 goto error;
1015 }
1016 ret = register_virtio_driver(&virtio_scsi_driver);
1017 if (ret < 0)
1018 goto error;
1019
1020 return 0;
1021
1022error:
1023 if (virtscsi_cmd_pool) {
1024 mempool_destroy(virtscsi_cmd_pool);
1025 virtscsi_cmd_pool = NULL;
1026 }
1027 if (virtscsi_cmd_cache) {
1028 kmem_cache_destroy(virtscsi_cmd_cache);
1029 virtscsi_cmd_cache = NULL;
1030 }
1031 return ret;
1032}
1033
1034static void __exit fini(void)
1035{
1036 unregister_virtio_driver(&virtio_scsi_driver);
1037 mempool_destroy(virtscsi_cmd_pool);
1038 kmem_cache_destroy(virtscsi_cmd_cache);
1039}
1040module_init(init);
1041module_exit(fini);
1042
1043MODULE_DEVICE_TABLE(virtio, id_table);
1044MODULE_DESCRIPTION("Virtio SCSI HBA driver");
1045MODULE_LICENSE("GPL");