2 * Virtio SCSI HBA driver
4 * Copyright IBM Corp. 2010
5 * Copyright Red Hat, Inc. 2011
8 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
9 * Paolo Bonzini <pbonzini@redhat.com>
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.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 #include <linux/module.h>
19 #include <linux/slab.h>
20 #include <linux/mempool.h>
21 #include <linux/interrupt.h>
22 #include <linux/virtio.h>
23 #include <linux/virtio_ids.h>
24 #include <linux/virtio_config.h>
25 #include <linux/virtio_scsi.h>
26 #include <linux/cpu.h>
27 #include <linux/blkdev.h>
28 #include <scsi/scsi_host.h>
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_cmnd.h>
31 #include <scsi/scsi_tcq.h>
32 #include <scsi/scsi_devinfo.h>
33 #include <linux/seqlock.h>
34 #include <linux/blk-mq-virtio.h>
36 #define VIRTIO_SCSI_MEMPOOL_SZ 64
37 #define VIRTIO_SCSI_EVENT_LEN 8
38 #define VIRTIO_SCSI_VQ_BASE 2
40 /* Command queue element */
41 struct virtio_scsi_cmd
{
43 struct completion
*comp
;
45 struct virtio_scsi_cmd_req cmd
;
46 struct virtio_scsi_cmd_req_pi cmd_pi
;
47 struct virtio_scsi_ctrl_tmf_req tmf
;
48 struct virtio_scsi_ctrl_an_req an
;
51 struct virtio_scsi_cmd_resp cmd
;
52 struct virtio_scsi_ctrl_tmf_resp tmf
;
53 struct virtio_scsi_ctrl_an_resp an
;
54 struct virtio_scsi_event evt
;
56 } ____cacheline_aligned_in_smp
;
58 struct virtio_scsi_event_node
{
59 struct virtio_scsi
*vscsi
;
60 struct virtio_scsi_event event
;
61 struct work_struct work
;
64 struct virtio_scsi_vq
{
72 * Per-target queue state.
74 * This struct holds the data needed by the queue steering policy. When a
75 * target is sent multiple requests, we need to drive them to the same queue so
76 * that FIFO processing order is kept. However, if a target was idle, we can
77 * choose a queue arbitrarily. In this case the queue is chosen according to
78 * the current VCPU, so the driver expects the number of request queues to be
79 * equal to the number of VCPUs. This makes it easy and fast to select the
80 * queue, and also lets the driver optimize the IRQ affinity for the virtqueues
81 * (each virtqueue's affinity is set to the CPU that "owns" the queue).
83 * tgt_seq is held to serialize reading and writing req_vq.
85 * Decrements of reqs are never concurrent with writes of req_vq: before the
86 * decrement reqs will be != 0; after the decrement the virtqueue completion
87 * routine will not use the req_vq so it can be changed by a new request.
88 * Thus they can happen outside the tgt_seq, provided of course we make reqs
91 struct virtio_scsi_target_state
{
94 /* Currently active virtqueue for requests sent to this target. */
95 struct virtio_scsi_vq
*req_vq
;
98 /* Driver instance state */
100 struct virtio_device
*vdev
;
102 /* Get some buffers ready for event vq */
103 struct virtio_scsi_event_node event_list
[VIRTIO_SCSI_EVENT_LEN
];
107 /* If the affinity hint is set for virtqueues */
108 bool affinity_hint_set
;
110 struct hlist_node node
;
112 /* Protected by event_vq lock */
115 struct virtio_scsi_vq ctrl_vq
;
116 struct virtio_scsi_vq event_vq
;
117 struct virtio_scsi_vq req_vqs
[];
120 static struct kmem_cache
*virtscsi_cmd_cache
;
121 static mempool_t
*virtscsi_cmd_pool
;
123 static inline struct Scsi_Host
*virtio_scsi_host(struct virtio_device
*vdev
)
128 static void virtscsi_compute_resid(struct scsi_cmnd
*sc
, u32 resid
)
133 if (!scsi_bidi_cmnd(sc
)) {
134 scsi_set_resid(sc
, resid
);
138 scsi_in(sc
)->resid
= min(resid
, scsi_in(sc
)->length
);
139 scsi_out(sc
)->resid
= resid
- scsi_in(sc
)->resid
;
143 * virtscsi_complete_cmd - finish a scsi_cmd and invoke scsi_done
145 * Called with vq_lock held.
147 static void virtscsi_complete_cmd(struct virtio_scsi
*vscsi
, void *buf
)
149 struct virtio_scsi_cmd
*cmd
= buf
;
150 struct scsi_cmnd
*sc
= cmd
->sc
;
151 struct virtio_scsi_cmd_resp
*resp
= &cmd
->resp
.cmd
;
153 dev_dbg(&sc
->device
->sdev_gendev
,
154 "cmd %p response %u status %#02x sense_len %u\n",
155 sc
, resp
->response
, resp
->status
, resp
->sense_len
);
157 sc
->result
= resp
->status
;
158 virtscsi_compute_resid(sc
, virtio32_to_cpu(vscsi
->vdev
, resp
->resid
));
159 switch (resp
->response
) {
160 case VIRTIO_SCSI_S_OK
:
161 set_host_byte(sc
, DID_OK
);
163 case VIRTIO_SCSI_S_OVERRUN
:
164 set_host_byte(sc
, DID_ERROR
);
166 case VIRTIO_SCSI_S_ABORTED
:
167 set_host_byte(sc
, DID_ABORT
);
169 case VIRTIO_SCSI_S_BAD_TARGET
:
170 set_host_byte(sc
, DID_BAD_TARGET
);
172 case VIRTIO_SCSI_S_RESET
:
173 set_host_byte(sc
, DID_RESET
);
175 case VIRTIO_SCSI_S_BUSY
:
176 set_host_byte(sc
, DID_BUS_BUSY
);
178 case VIRTIO_SCSI_S_TRANSPORT_FAILURE
:
179 set_host_byte(sc
, DID_TRANSPORT_DISRUPTED
);
181 case VIRTIO_SCSI_S_TARGET_FAILURE
:
182 set_host_byte(sc
, DID_TARGET_FAILURE
);
184 case VIRTIO_SCSI_S_NEXUS_FAILURE
:
185 set_host_byte(sc
, DID_NEXUS_FAILURE
);
188 scmd_printk(KERN_WARNING
, sc
, "Unknown response %d",
191 case VIRTIO_SCSI_S_FAILURE
:
192 set_host_byte(sc
, DID_ERROR
);
196 WARN_ON(virtio32_to_cpu(vscsi
->vdev
, resp
->sense_len
) >
197 VIRTIO_SCSI_SENSE_SIZE
);
198 if (sc
->sense_buffer
) {
199 memcpy(sc
->sense_buffer
, resp
->sense
,
201 virtio32_to_cpu(vscsi
->vdev
, resp
->sense_len
),
202 VIRTIO_SCSI_SENSE_SIZE
));
204 set_driver_byte(sc
, DRIVER_SENSE
);
210 static void virtscsi_vq_done(struct virtio_scsi
*vscsi
,
211 struct virtio_scsi_vq
*virtscsi_vq
,
212 void (*fn
)(struct virtio_scsi
*vscsi
, void *buf
))
217 struct virtqueue
*vq
= virtscsi_vq
->vq
;
219 spin_lock_irqsave(&virtscsi_vq
->vq_lock
, flags
);
221 virtqueue_disable_cb(vq
);
222 while ((buf
= virtqueue_get_buf(vq
, &len
)) != NULL
)
225 if (unlikely(virtqueue_is_broken(vq
)))
227 } while (!virtqueue_enable_cb(vq
));
228 spin_unlock_irqrestore(&virtscsi_vq
->vq_lock
, flags
);
231 static void virtscsi_req_done(struct virtqueue
*vq
)
233 struct Scsi_Host
*sh
= virtio_scsi_host(vq
->vdev
);
234 struct virtio_scsi
*vscsi
= shost_priv(sh
);
235 int index
= vq
->index
- VIRTIO_SCSI_VQ_BASE
;
236 struct virtio_scsi_vq
*req_vq
= &vscsi
->req_vqs
[index
];
238 virtscsi_vq_done(vscsi
, req_vq
, virtscsi_complete_cmd
);
241 static void virtscsi_poll_requests(struct virtio_scsi
*vscsi
)
245 num_vqs
= vscsi
->num_queues
;
246 for (i
= 0; i
< num_vqs
; i
++)
247 virtscsi_vq_done(vscsi
, &vscsi
->req_vqs
[i
],
248 virtscsi_complete_cmd
);
251 static void virtscsi_complete_free(struct virtio_scsi
*vscsi
, void *buf
)
253 struct virtio_scsi_cmd
*cmd
= buf
;
259 static void virtscsi_ctrl_done(struct virtqueue
*vq
)
261 struct Scsi_Host
*sh
= virtio_scsi_host(vq
->vdev
);
262 struct virtio_scsi
*vscsi
= shost_priv(sh
);
264 virtscsi_vq_done(vscsi
, &vscsi
->ctrl_vq
, virtscsi_complete_free
);
267 static void virtscsi_handle_event(struct work_struct
*work
);
269 static int virtscsi_kick_event(struct virtio_scsi
*vscsi
,
270 struct virtio_scsi_event_node
*event_node
)
273 struct scatterlist sg
;
276 INIT_WORK(&event_node
->work
, virtscsi_handle_event
);
277 sg_init_one(&sg
, &event_node
->event
, sizeof(struct virtio_scsi_event
));
279 spin_lock_irqsave(&vscsi
->event_vq
.vq_lock
, flags
);
281 err
= virtqueue_add_inbuf(vscsi
->event_vq
.vq
, &sg
, 1, event_node
,
284 virtqueue_kick(vscsi
->event_vq
.vq
);
286 spin_unlock_irqrestore(&vscsi
->event_vq
.vq_lock
, flags
);
291 static int virtscsi_kick_event_all(struct virtio_scsi
*vscsi
)
295 for (i
= 0; i
< VIRTIO_SCSI_EVENT_LEN
; i
++) {
296 vscsi
->event_list
[i
].vscsi
= vscsi
;
297 virtscsi_kick_event(vscsi
, &vscsi
->event_list
[i
]);
303 static void virtscsi_cancel_event_work(struct virtio_scsi
*vscsi
)
307 /* Stop scheduling work before calling cancel_work_sync. */
308 spin_lock_irq(&vscsi
->event_vq
.vq_lock
);
309 vscsi
->stop_events
= true;
310 spin_unlock_irq(&vscsi
->event_vq
.vq_lock
);
312 for (i
= 0; i
< VIRTIO_SCSI_EVENT_LEN
; i
++)
313 cancel_work_sync(&vscsi
->event_list
[i
].work
);
316 static void virtscsi_handle_transport_reset(struct virtio_scsi
*vscsi
,
317 struct virtio_scsi_event
*event
)
319 struct scsi_device
*sdev
;
320 struct Scsi_Host
*shost
= virtio_scsi_host(vscsi
->vdev
);
321 unsigned int target
= event
->lun
[1];
322 unsigned int lun
= (event
->lun
[2] << 8) | event
->lun
[3];
324 switch (virtio32_to_cpu(vscsi
->vdev
, event
->reason
)) {
325 case VIRTIO_SCSI_EVT_RESET_RESCAN
:
326 scsi_add_device(shost
, 0, target
, lun
);
328 case VIRTIO_SCSI_EVT_RESET_REMOVED
:
329 sdev
= scsi_device_lookup(shost
, 0, target
, lun
);
331 scsi_remove_device(sdev
);
332 scsi_device_put(sdev
);
334 pr_err("SCSI device %d 0 %d %d not found\n",
335 shost
->host_no
, target
, lun
);
339 pr_info("Unsupport virtio scsi event reason %x\n", event
->reason
);
343 static void virtscsi_handle_param_change(struct virtio_scsi
*vscsi
,
344 struct virtio_scsi_event
*event
)
346 struct scsi_device
*sdev
;
347 struct Scsi_Host
*shost
= virtio_scsi_host(vscsi
->vdev
);
348 unsigned int target
= event
->lun
[1];
349 unsigned int lun
= (event
->lun
[2] << 8) | event
->lun
[3];
350 u8 asc
= virtio32_to_cpu(vscsi
->vdev
, event
->reason
) & 255;
351 u8 ascq
= virtio32_to_cpu(vscsi
->vdev
, event
->reason
) >> 8;
353 sdev
= scsi_device_lookup(shost
, 0, target
, lun
);
355 pr_err("SCSI device %d 0 %d %d not found\n",
356 shost
->host_no
, target
, lun
);
360 /* Handle "Parameters changed", "Mode parameters changed", and
361 "Capacity data has changed". */
362 if (asc
== 0x2a && (ascq
== 0x00 || ascq
== 0x01 || ascq
== 0x09))
363 scsi_rescan_device(&sdev
->sdev_gendev
);
365 scsi_device_put(sdev
);
368 static void virtscsi_handle_event(struct work_struct
*work
)
370 struct virtio_scsi_event_node
*event_node
=
371 container_of(work
, struct virtio_scsi_event_node
, work
);
372 struct virtio_scsi
*vscsi
= event_node
->vscsi
;
373 struct virtio_scsi_event
*event
= &event_node
->event
;
376 cpu_to_virtio32(vscsi
->vdev
, VIRTIO_SCSI_T_EVENTS_MISSED
)) {
377 event
->event
&= ~cpu_to_virtio32(vscsi
->vdev
,
378 VIRTIO_SCSI_T_EVENTS_MISSED
);
379 scsi_scan_host(virtio_scsi_host(vscsi
->vdev
));
382 switch (virtio32_to_cpu(vscsi
->vdev
, event
->event
)) {
383 case VIRTIO_SCSI_T_NO_EVENT
:
385 case VIRTIO_SCSI_T_TRANSPORT_RESET
:
386 virtscsi_handle_transport_reset(vscsi
, event
);
388 case VIRTIO_SCSI_T_PARAM_CHANGE
:
389 virtscsi_handle_param_change(vscsi
, event
);
392 pr_err("Unsupport virtio scsi event %x\n", event
->event
);
394 virtscsi_kick_event(vscsi
, event_node
);
397 static void virtscsi_complete_event(struct virtio_scsi
*vscsi
, void *buf
)
399 struct virtio_scsi_event_node
*event_node
= buf
;
401 if (!vscsi
->stop_events
)
402 queue_work(system_freezable_wq
, &event_node
->work
);
405 static void virtscsi_event_done(struct virtqueue
*vq
)
407 struct Scsi_Host
*sh
= virtio_scsi_host(vq
->vdev
);
408 struct virtio_scsi
*vscsi
= shost_priv(sh
);
410 virtscsi_vq_done(vscsi
, &vscsi
->event_vq
, virtscsi_complete_event
);
414 * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue
415 * @vq : the struct virtqueue we're talking about
416 * @cmd : command structure
417 * @req_size : size of the request buffer
418 * @resp_size : size of the response buffer
420 static int virtscsi_add_cmd(struct virtqueue
*vq
,
421 struct virtio_scsi_cmd
*cmd
,
422 size_t req_size
, size_t resp_size
)
424 struct scsi_cmnd
*sc
= cmd
->sc
;
425 struct scatterlist
*sgs
[6], req
, resp
;
426 struct sg_table
*out
, *in
;
427 unsigned out_num
= 0, in_num
= 0;
431 if (sc
&& sc
->sc_data_direction
!= DMA_NONE
) {
432 if (sc
->sc_data_direction
!= DMA_FROM_DEVICE
)
433 out
= &scsi_out(sc
)->table
;
434 if (sc
->sc_data_direction
!= DMA_TO_DEVICE
)
435 in
= &scsi_in(sc
)->table
;
438 /* Request header. */
439 sg_init_one(&req
, &cmd
->req
, req_size
);
440 sgs
[out_num
++] = &req
;
442 /* Data-out buffer. */
444 /* Place WRITE protection SGLs before Data OUT payload */
445 if (scsi_prot_sg_count(sc
))
446 sgs
[out_num
++] = scsi_prot_sglist(sc
);
447 sgs
[out_num
++] = out
->sgl
;
450 /* Response header. */
451 sg_init_one(&resp
, &cmd
->resp
, resp_size
);
452 sgs
[out_num
+ in_num
++] = &resp
;
456 /* Place READ protection SGLs before Data IN payload */
457 if (scsi_prot_sg_count(sc
))
458 sgs
[out_num
+ in_num
++] = scsi_prot_sglist(sc
);
459 sgs
[out_num
+ in_num
++] = in
->sgl
;
462 return virtqueue_add_sgs(vq
, sgs
, out_num
, in_num
, cmd
, GFP_ATOMIC
);
465 static int virtscsi_kick_cmd(struct virtio_scsi_vq
*vq
,
466 struct virtio_scsi_cmd
*cmd
,
467 size_t req_size
, size_t resp_size
)
471 bool needs_kick
= false;
473 spin_lock_irqsave(&vq
->vq_lock
, flags
);
474 err
= virtscsi_add_cmd(vq
->vq
, cmd
, req_size
, resp_size
);
476 needs_kick
= virtqueue_kick_prepare(vq
->vq
);
478 spin_unlock_irqrestore(&vq
->vq_lock
, flags
);
481 virtqueue_notify(vq
->vq
);
485 static void virtio_scsi_init_hdr(struct virtio_device
*vdev
,
486 struct virtio_scsi_cmd_req
*cmd
,
487 struct scsi_cmnd
*sc
)
490 cmd
->lun
[1] = sc
->device
->id
;
491 cmd
->lun
[2] = (sc
->device
->lun
>> 8) | 0x40;
492 cmd
->lun
[3] = sc
->device
->lun
& 0xff;
493 cmd
->tag
= cpu_to_virtio64(vdev
, (unsigned long)sc
);
494 cmd
->task_attr
= VIRTIO_SCSI_S_SIMPLE
;
499 #ifdef CONFIG_BLK_DEV_INTEGRITY
500 static void virtio_scsi_init_hdr_pi(struct virtio_device
*vdev
,
501 struct virtio_scsi_cmd_req_pi
*cmd_pi
,
502 struct scsi_cmnd
*sc
)
504 struct request
*rq
= sc
->request
;
505 struct blk_integrity
*bi
;
507 virtio_scsi_init_hdr(vdev
, (struct virtio_scsi_cmd_req
*)cmd_pi
, sc
);
509 if (!rq
|| !scsi_prot_sg_count(sc
))
512 bi
= blk_get_integrity(rq
->rq_disk
);
514 if (sc
->sc_data_direction
== DMA_TO_DEVICE
)
515 cmd_pi
->pi_bytesout
= cpu_to_virtio32(vdev
,
518 else if (sc
->sc_data_direction
== DMA_FROM_DEVICE
)
519 cmd_pi
->pi_bytesin
= cpu_to_virtio32(vdev
,
525 static int virtscsi_queuecommand(struct virtio_scsi
*vscsi
,
526 struct virtio_scsi_vq
*req_vq
,
527 struct scsi_cmnd
*sc
)
529 struct Scsi_Host
*shost
= virtio_scsi_host(vscsi
->vdev
);
530 struct virtio_scsi_cmd
*cmd
= scsi_cmd_priv(sc
);
535 BUG_ON(scsi_sg_count(sc
) > shost
->sg_tablesize
);
537 /* TODO: check feature bit and fail if unsupported? */
538 BUG_ON(sc
->sc_data_direction
== DMA_BIDIRECTIONAL
);
540 dev_dbg(&sc
->device
->sdev_gendev
,
541 "cmd %p CDB: %#02x\n", sc
, sc
->cmnd
[0]);
545 BUG_ON(sc
->cmd_len
> VIRTIO_SCSI_CDB_SIZE
);
547 #ifdef CONFIG_BLK_DEV_INTEGRITY
548 if (virtio_has_feature(vscsi
->vdev
, VIRTIO_SCSI_F_T10_PI
)) {
549 virtio_scsi_init_hdr_pi(vscsi
->vdev
, &cmd
->req
.cmd_pi
, sc
);
550 memcpy(cmd
->req
.cmd_pi
.cdb
, sc
->cmnd
, sc
->cmd_len
);
551 req_size
= sizeof(cmd
->req
.cmd_pi
);
555 virtio_scsi_init_hdr(vscsi
->vdev
, &cmd
->req
.cmd
, sc
);
556 memcpy(cmd
->req
.cmd
.cdb
, sc
->cmnd
, sc
->cmd_len
);
557 req_size
= sizeof(cmd
->req
.cmd
);
560 ret
= virtscsi_kick_cmd(req_vq
, cmd
, req_size
, sizeof(cmd
->resp
.cmd
));
562 cmd
->resp
.cmd
.response
= VIRTIO_SCSI_S_BAD_TARGET
;
563 spin_lock_irqsave(&req_vq
->vq_lock
, flags
);
564 virtscsi_complete_cmd(vscsi
, cmd
);
565 spin_unlock_irqrestore(&req_vq
->vq_lock
, flags
);
566 } else if (ret
!= 0) {
567 return SCSI_MLQUEUE_HOST_BUSY
;
572 static int virtscsi_queuecommand_single(struct Scsi_Host
*sh
,
573 struct scsi_cmnd
*sc
)
575 struct virtio_scsi
*vscsi
= shost_priv(sh
);
577 return virtscsi_queuecommand(vscsi
, &vscsi
->req_vqs
[0], sc
);
580 static struct virtio_scsi_vq
*virtscsi_pick_vq_mq(struct virtio_scsi
*vscsi
,
581 struct scsi_cmnd
*sc
)
583 u32 tag
= blk_mq_unique_tag(sc
->request
);
584 u16 hwq
= blk_mq_unique_tag_to_hwq(tag
);
586 return &vscsi
->req_vqs
[hwq
];
589 static int virtscsi_queuecommand_multi(struct Scsi_Host
*sh
,
590 struct scsi_cmnd
*sc
)
592 struct virtio_scsi
*vscsi
= shost_priv(sh
);
593 struct virtio_scsi_vq
*req_vq
= virtscsi_pick_vq_mq(vscsi
, sc
);
595 return virtscsi_queuecommand(vscsi
, req_vq
, sc
);
598 static int virtscsi_tmf(struct virtio_scsi
*vscsi
, struct virtio_scsi_cmd
*cmd
)
600 DECLARE_COMPLETION_ONSTACK(comp
);
604 if (virtscsi_kick_cmd(&vscsi
->ctrl_vq
, cmd
,
605 sizeof cmd
->req
.tmf
, sizeof cmd
->resp
.tmf
) < 0)
608 wait_for_completion(&comp
);
609 if (cmd
->resp
.tmf
.response
== VIRTIO_SCSI_S_OK
||
610 cmd
->resp
.tmf
.response
== VIRTIO_SCSI_S_FUNCTION_SUCCEEDED
)
614 * The spec guarantees that all requests related to the TMF have
615 * been completed, but the callback might not have run yet if
616 * we're using independent interrupts (e.g. MSI). Poll the
619 * In the abort case, sc->scsi_done will do nothing, because
620 * the block layer must have detected a timeout and as a result
621 * REQ_ATOM_COMPLETE has been set.
623 virtscsi_poll_requests(vscsi
);
626 mempool_free(cmd
, virtscsi_cmd_pool
);
630 static int virtscsi_device_reset(struct scsi_cmnd
*sc
)
632 struct virtio_scsi
*vscsi
= shost_priv(sc
->device
->host
);
633 struct virtio_scsi_cmd
*cmd
;
635 sdev_printk(KERN_INFO
, sc
->device
, "device reset\n");
636 cmd
= mempool_alloc(virtscsi_cmd_pool
, GFP_NOIO
);
640 memset(cmd
, 0, sizeof(*cmd
));
642 cmd
->req
.tmf
= (struct virtio_scsi_ctrl_tmf_req
){
643 .type
= VIRTIO_SCSI_T_TMF
,
644 .subtype
= cpu_to_virtio32(vscsi
->vdev
,
645 VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET
),
647 .lun
[1] = sc
->device
->id
,
648 .lun
[2] = (sc
->device
->lun
>> 8) | 0x40,
649 .lun
[3] = sc
->device
->lun
& 0xff,
651 return virtscsi_tmf(vscsi
, cmd
);
654 static int virtscsi_device_alloc(struct scsi_device
*sdevice
)
657 * Passed through SCSI targets (e.g. with qemu's 'scsi-block')
658 * may have transfer limits which come from the host SCSI
659 * controller or something on the host side other than the
662 * To make this work properly, the hypervisor can adjust the
663 * target's VPD information to advertise these limits. But
664 * for that to work, the guest has to look at the VPD pages,
665 * which we won't do by default if it is an SPC-2 device, even
666 * if it does actually support it.
668 * So, set the blist to always try to read the VPD pages.
670 sdevice
->sdev_bflags
= BLIST_TRY_VPD_PAGES
;
677 * virtscsi_change_queue_depth() - Change a virtscsi target's queue depth
678 * @sdev: Virtscsi target whose queue depth to change
679 * @qdepth: New queue depth
681 static int virtscsi_change_queue_depth(struct scsi_device
*sdev
, int qdepth
)
683 struct Scsi_Host
*shost
= sdev
->host
;
684 int max_depth
= shost
->cmd_per_lun
;
686 return scsi_change_queue_depth(sdev
, min(max_depth
, qdepth
));
689 static int virtscsi_abort(struct scsi_cmnd
*sc
)
691 struct virtio_scsi
*vscsi
= shost_priv(sc
->device
->host
);
692 struct virtio_scsi_cmd
*cmd
;
694 scmd_printk(KERN_INFO
, sc
, "abort\n");
695 cmd
= mempool_alloc(virtscsi_cmd_pool
, GFP_NOIO
);
699 memset(cmd
, 0, sizeof(*cmd
));
701 cmd
->req
.tmf
= (struct virtio_scsi_ctrl_tmf_req
){
702 .type
= VIRTIO_SCSI_T_TMF
,
703 .subtype
= VIRTIO_SCSI_T_TMF_ABORT_TASK
,
705 .lun
[1] = sc
->device
->id
,
706 .lun
[2] = (sc
->device
->lun
>> 8) | 0x40,
707 .lun
[3] = sc
->device
->lun
& 0xff,
708 .tag
= cpu_to_virtio64(vscsi
->vdev
, (unsigned long)sc
),
710 return virtscsi_tmf(vscsi
, cmd
);
713 static int virtscsi_target_alloc(struct scsi_target
*starget
)
715 struct Scsi_Host
*sh
= dev_to_shost(starget
->dev
.parent
);
716 struct virtio_scsi
*vscsi
= shost_priv(sh
);
718 struct virtio_scsi_target_state
*tgt
=
719 kmalloc(sizeof(*tgt
), GFP_KERNEL
);
723 seqcount_init(&tgt
->tgt_seq
);
724 tgt
->req_vq
= &vscsi
->req_vqs
[0];
726 starget
->hostdata
= tgt
;
730 static void virtscsi_target_destroy(struct scsi_target
*starget
)
732 struct virtio_scsi_target_state
*tgt
= starget
->hostdata
;
736 static int virtscsi_map_queues(struct Scsi_Host
*shost
)
738 struct virtio_scsi
*vscsi
= shost_priv(shost
);
740 return blk_mq_virtio_map_queues(&shost
->tag_set
, vscsi
->vdev
, 2);
744 * The host guarantees to respond to each command, although I/O
745 * latencies might be higher than on bare metal. Reset the timer
746 * unconditionally to give the host a chance to perform EH.
748 static enum blk_eh_timer_return
virtscsi_eh_timed_out(struct scsi_cmnd
*scmnd
)
750 return BLK_EH_RESET_TIMER
;
753 static struct scsi_host_template virtscsi_host_template_single
= {
754 .module
= THIS_MODULE
,
755 .name
= "Virtio SCSI HBA",
756 .proc_name
= "virtio_scsi",
758 .cmd_size
= sizeof(struct virtio_scsi_cmd
),
759 .queuecommand
= virtscsi_queuecommand_single
,
760 .change_queue_depth
= virtscsi_change_queue_depth
,
761 .eh_abort_handler
= virtscsi_abort
,
762 .eh_device_reset_handler
= virtscsi_device_reset
,
763 .eh_timed_out
= virtscsi_eh_timed_out
,
764 .slave_alloc
= virtscsi_device_alloc
,
766 .dma_boundary
= UINT_MAX
,
767 .use_clustering
= ENABLE_CLUSTERING
,
768 .target_alloc
= virtscsi_target_alloc
,
769 .target_destroy
= virtscsi_target_destroy
,
770 .track_queue_depth
= 1,
774 static struct scsi_host_template virtscsi_host_template_multi
= {
775 .module
= THIS_MODULE
,
776 .name
= "Virtio SCSI HBA",
777 .proc_name
= "virtio_scsi",
779 .cmd_size
= sizeof(struct virtio_scsi_cmd
),
780 .queuecommand
= virtscsi_queuecommand_multi
,
781 .change_queue_depth
= virtscsi_change_queue_depth
,
782 .eh_abort_handler
= virtscsi_abort
,
783 .eh_device_reset_handler
= virtscsi_device_reset
,
784 .eh_timed_out
= virtscsi_eh_timed_out
,
785 .slave_alloc
= virtscsi_device_alloc
,
787 .dma_boundary
= UINT_MAX
,
788 .use_clustering
= ENABLE_CLUSTERING
,
789 .target_alloc
= virtscsi_target_alloc
,
790 .target_destroy
= virtscsi_target_destroy
,
791 .map_queues
= virtscsi_map_queues
,
792 .track_queue_depth
= 1,
796 #define virtscsi_config_get(vdev, fld) \
798 typeof(((struct virtio_scsi_config *)0)->fld) __val; \
799 virtio_cread(vdev, struct virtio_scsi_config, fld, &__val); \
803 #define virtscsi_config_set(vdev, fld, val) \
805 typeof(((struct virtio_scsi_config *)0)->fld) __val = (val); \
806 virtio_cwrite(vdev, struct virtio_scsi_config, fld, &__val); \
809 static void virtscsi_init_vq(struct virtio_scsi_vq
*virtscsi_vq
,
810 struct virtqueue
*vq
)
812 spin_lock_init(&virtscsi_vq
->vq_lock
);
813 virtscsi_vq
->vq
= vq
;
816 static void virtscsi_remove_vqs(struct virtio_device
*vdev
)
818 /* Stop all the virtqueues. */
819 vdev
->config
->reset(vdev
);
820 vdev
->config
->del_vqs(vdev
);
823 static int virtscsi_init(struct virtio_device
*vdev
,
824 struct virtio_scsi
*vscsi
)
829 vq_callback_t
**callbacks
;
831 struct virtqueue
**vqs
;
832 struct irq_affinity desc
= { .pre_vectors
= 2 };
834 num_vqs
= vscsi
->num_queues
+ VIRTIO_SCSI_VQ_BASE
;
835 vqs
= kmalloc(num_vqs
* sizeof(struct virtqueue
*), GFP_KERNEL
);
836 callbacks
= kmalloc(num_vqs
* sizeof(vq_callback_t
*), GFP_KERNEL
);
837 names
= kmalloc(num_vqs
* sizeof(char *), GFP_KERNEL
);
839 if (!callbacks
|| !vqs
|| !names
) {
844 callbacks
[0] = virtscsi_ctrl_done
;
845 callbacks
[1] = virtscsi_event_done
;
846 names
[0] = "control";
848 for (i
= VIRTIO_SCSI_VQ_BASE
; i
< num_vqs
; i
++) {
849 callbacks
[i
] = virtscsi_req_done
;
850 names
[i
] = "request";
853 /* Discover virtqueues and write information to configuration. */
854 err
= virtio_find_vqs(vdev
, num_vqs
, vqs
, callbacks
, names
, &desc
);
858 virtscsi_init_vq(&vscsi
->ctrl_vq
, vqs
[0]);
859 virtscsi_init_vq(&vscsi
->event_vq
, vqs
[1]);
860 for (i
= VIRTIO_SCSI_VQ_BASE
; i
< num_vqs
; i
++)
861 virtscsi_init_vq(&vscsi
->req_vqs
[i
- VIRTIO_SCSI_VQ_BASE
],
864 virtscsi_config_set(vdev
, cdb_size
, VIRTIO_SCSI_CDB_SIZE
);
865 virtscsi_config_set(vdev
, sense_size
, VIRTIO_SCSI_SENSE_SIZE
);
874 virtscsi_remove_vqs(vdev
);
878 static int virtscsi_probe(struct virtio_device
*vdev
)
880 struct Scsi_Host
*shost
;
881 struct virtio_scsi
*vscsi
;
883 u32 sg_elems
, num_targets
;
886 struct scsi_host_template
*hostt
;
888 if (!vdev
->config
->get
) {
889 dev_err(&vdev
->dev
, "%s failure: config access disabled\n",
894 /* We need to know how many queues before we allocate. */
895 num_queues
= virtscsi_config_get(vdev
, num_queues
) ? : 1;
897 num_targets
= virtscsi_config_get(vdev
, max_target
) + 1;
900 hostt
= &virtscsi_host_template_single
;
902 hostt
= &virtscsi_host_template_multi
;
904 shost
= scsi_host_alloc(hostt
,
905 sizeof(*vscsi
) + sizeof(vscsi
->req_vqs
[0]) * num_queues
);
909 sg_elems
= virtscsi_config_get(vdev
, seg_max
) ?: 1;
910 shost
->sg_tablesize
= sg_elems
;
911 vscsi
= shost_priv(shost
);
913 vscsi
->num_queues
= num_queues
;
916 err
= virtscsi_init(vdev
, vscsi
);
918 goto virtscsi_init_failed
;
920 shost
->can_queue
= virtqueue_get_vring_size(vscsi
->req_vqs
[0].vq
);
922 cmd_per_lun
= virtscsi_config_get(vdev
, cmd_per_lun
) ?: 1;
923 shost
->cmd_per_lun
= min_t(u32
, cmd_per_lun
, shost
->can_queue
);
924 shost
->max_sectors
= virtscsi_config_get(vdev
, max_sectors
) ?: 0xFFFF;
926 /* LUNs > 256 are reported with format 1, so they go in the range
929 shost
->max_lun
= virtscsi_config_get(vdev
, max_lun
) + 1 + 0x4000;
930 shost
->max_id
= num_targets
;
931 shost
->max_channel
= 0;
932 shost
->max_cmd_len
= VIRTIO_SCSI_CDB_SIZE
;
933 shost
->nr_hw_queues
= num_queues
;
935 #ifdef CONFIG_BLK_DEV_INTEGRITY
936 if (virtio_has_feature(vdev
, VIRTIO_SCSI_F_T10_PI
)) {
939 host_prot
= SHOST_DIF_TYPE1_PROTECTION
| SHOST_DIF_TYPE2_PROTECTION
|
940 SHOST_DIF_TYPE3_PROTECTION
| SHOST_DIX_TYPE1_PROTECTION
|
941 SHOST_DIX_TYPE2_PROTECTION
| SHOST_DIX_TYPE3_PROTECTION
;
943 scsi_host_set_prot(shost
, host_prot
);
944 scsi_host_set_guard(shost
, SHOST_DIX_GUARD_CRC
);
948 err
= scsi_add_host(shost
, &vdev
->dev
);
950 goto scsi_add_host_failed
;
952 virtio_device_ready(vdev
);
954 if (virtio_has_feature(vdev
, VIRTIO_SCSI_F_HOTPLUG
))
955 virtscsi_kick_event_all(vscsi
);
957 scsi_scan_host(shost
);
960 scsi_add_host_failed
:
961 vdev
->config
->del_vqs(vdev
);
962 virtscsi_init_failed
:
963 scsi_host_put(shost
);
967 static void virtscsi_remove(struct virtio_device
*vdev
)
969 struct Scsi_Host
*shost
= virtio_scsi_host(vdev
);
970 struct virtio_scsi
*vscsi
= shost_priv(shost
);
972 if (virtio_has_feature(vdev
, VIRTIO_SCSI_F_HOTPLUG
))
973 virtscsi_cancel_event_work(vscsi
);
975 scsi_remove_host(shost
);
976 virtscsi_remove_vqs(vdev
);
977 scsi_host_put(shost
);
980 #ifdef CONFIG_PM_SLEEP
981 static int virtscsi_freeze(struct virtio_device
*vdev
)
983 virtscsi_remove_vqs(vdev
);
987 static int virtscsi_restore(struct virtio_device
*vdev
)
989 struct Scsi_Host
*sh
= virtio_scsi_host(vdev
);
990 struct virtio_scsi
*vscsi
= shost_priv(sh
);
993 err
= virtscsi_init(vdev
, vscsi
);
997 virtio_device_ready(vdev
);
999 if (virtio_has_feature(vdev
, VIRTIO_SCSI_F_HOTPLUG
))
1000 virtscsi_kick_event_all(vscsi
);
1006 static struct virtio_device_id id_table
[] = {
1007 { VIRTIO_ID_SCSI
, VIRTIO_DEV_ANY_ID
},
1011 static unsigned int features
[] = {
1012 VIRTIO_SCSI_F_HOTPLUG
,
1013 VIRTIO_SCSI_F_CHANGE
,
1014 #ifdef CONFIG_BLK_DEV_INTEGRITY
1015 VIRTIO_SCSI_F_T10_PI
,
1019 static struct virtio_driver virtio_scsi_driver
= {
1020 .feature_table
= features
,
1021 .feature_table_size
= ARRAY_SIZE(features
),
1022 .driver
.name
= KBUILD_MODNAME
,
1023 .driver
.owner
= THIS_MODULE
,
1024 .id_table
= id_table
,
1025 .probe
= virtscsi_probe
,
1026 #ifdef CONFIG_PM_SLEEP
1027 .freeze
= virtscsi_freeze
,
1028 .restore
= virtscsi_restore
,
1030 .remove
= virtscsi_remove
,
1033 static int __init
init(void)
1037 virtscsi_cmd_cache
= KMEM_CACHE(virtio_scsi_cmd
, 0);
1038 if (!virtscsi_cmd_cache
) {
1039 pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n");
1045 mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ
,
1046 virtscsi_cmd_cache
);
1047 if (!virtscsi_cmd_pool
) {
1048 pr_err("mempool_create() for virtscsi_cmd_pool failed\n");
1051 ret
= register_virtio_driver(&virtio_scsi_driver
);
1058 if (virtscsi_cmd_pool
) {
1059 mempool_destroy(virtscsi_cmd_pool
);
1060 virtscsi_cmd_pool
= NULL
;
1062 if (virtscsi_cmd_cache
) {
1063 kmem_cache_destroy(virtscsi_cmd_cache
);
1064 virtscsi_cmd_cache
= NULL
;
1069 static void __exit
fini(void)
1071 unregister_virtio_driver(&virtio_scsi_driver
);
1072 mempool_destroy(virtscsi_cmd_pool
);
1073 kmem_cache_destroy(virtscsi_cmd_cache
);
1078 MODULE_DEVICE_TABLE(virtio
, id_table
);
1079 MODULE_DESCRIPTION("Virtio SCSI HBA driver");
1080 MODULE_LICENSE("GPL");