1 // SPDX-License-Identifier: GPL-2.0+
2 /*******************************************************************************
3 * Vhost kernel TCM fabric driver for virtio SCSI initiators
4 *
5 * (C) Copyright 2010-2013 Datera, Inc.
6 * (C) Copyright 2010-2012 IBM Corp.
7 *
8 * Authors: Nicholas A. Bellinger <nab@daterainc.com>
9 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
10 ****************************************************************************/
11
12 #include <linux/module.h>
13 #include <linux/moduleparam.h>
14 #include <generated/utsrelease.h>
15 #include <linux/utsname.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/kthread.h>
19 #include <linux/types.h>
20 #include <linux/string.h>
21 #include <linux/configfs.h>
22 #include <linux/ctype.h>
23 #include <linux/compat.h>
24 #include <linux/eventfd.h>
25 #include <linux/fs.h>
26 #include <linux/vmalloc.h>
27 #include <linux/miscdevice.h>
28 #include <linux/blk_types.h>
29 #include <linux/bio.h>
30 #include <linux/unaligned.h>
31 #include <scsi/scsi_common.h>
32 #include <scsi/scsi_proto.h>
33 #include <target/target_core_base.h>
34 #include <target/target_core_fabric.h>
35 #include <linux/vhost.h>
36 #include <linux/virtio_scsi.h>
37 #include <linux/llist.h>
38 #include <linux/bitmap.h>
39
40 #include "vhost.h"
41
42 #define VHOST_SCSI_VERSION "v0.1"
43 #define VHOST_SCSI_NAMELEN 256
44 #define VHOST_SCSI_MAX_CDB_SIZE 32
45 #define VHOST_SCSI_PREALLOC_SGLS 2048
46 #define VHOST_SCSI_PREALLOC_UPAGES 2048
47 #define VHOST_SCSI_PREALLOC_PROT_SGLS 2048
48 /*
49 * For the legacy descriptor case we allocate an iov per byte in the
50 * virtio_scsi_cmd_resp struct.
51 */
52 #define VHOST_SCSI_MAX_RESP_IOVS sizeof(struct virtio_scsi_cmd_resp)
53
54 static unsigned int vhost_scsi_inline_sg_cnt = VHOST_SCSI_PREALLOC_SGLS;
55
56 #ifdef CONFIG_ARCH_NO_SG_CHAIN
vhost_scsi_set_inline_sg_cnt(const char * buf,const struct kernel_param * kp)57 static int vhost_scsi_set_inline_sg_cnt(const char *buf,
58 const struct kernel_param *kp)
59 {
60 pr_err("Setting inline_sg_cnt is not supported.\n");
61 return -EOPNOTSUPP;
62 }
63 #else
vhost_scsi_set_inline_sg_cnt(const char * buf,const struct kernel_param * kp)64 static int vhost_scsi_set_inline_sg_cnt(const char *buf,
65 const struct kernel_param *kp)
66 {
67 unsigned int cnt;
68 int ret;
69
70 ret = kstrtouint(buf, 10, &cnt);
71 if (ret)
72 return ret;
73
74 if (cnt > VHOST_SCSI_PREALLOC_SGLS) {
75 pr_err("Max inline_sg_cnt is %u\n", VHOST_SCSI_PREALLOC_SGLS);
76 return -EINVAL;
77 }
78
79 vhost_scsi_inline_sg_cnt = cnt;
80 return 0;
81 }
82 #endif
83
vhost_scsi_get_inline_sg_cnt(char * buf,const struct kernel_param * kp)84 static int vhost_scsi_get_inline_sg_cnt(char *buf,
85 const struct kernel_param *kp)
86 {
87 return sprintf(buf, "%u\n", vhost_scsi_inline_sg_cnt);
88 }
89
90 static const struct kernel_param_ops vhost_scsi_inline_sg_cnt_op = {
91 .get = vhost_scsi_get_inline_sg_cnt,
92 .set = vhost_scsi_set_inline_sg_cnt,
93 };
94
95 module_param_cb(inline_sg_cnt, &vhost_scsi_inline_sg_cnt_op, NULL, 0644);
96 MODULE_PARM_DESC(inline_sg_cnt, "Set the number of scatterlist entries to pre-allocate. The default is 2048.");
97
98 /* Max number of requests before requeueing the job.
99 * Using this limit prevents one virtqueue from starving others with
100 * request.
101 */
102 #define VHOST_SCSI_WEIGHT 256
103
104 struct vhost_scsi_inflight {
105 /* Wait for the flush operation to finish */
106 struct completion comp;
107 /* Refcount for the inflight reqs */
108 struct kref kref;
109 };
110
111 struct vhost_scsi_cmd {
112 /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
113 int tvc_vq_desc;
114 /* The number of scatterlists associated with this cmd */
115 u32 tvc_sgl_count;
116 u32 tvc_prot_sgl_count;
117 u32 copied_iov:1;
118 const void *read_iov;
119 struct iov_iter *read_iter;
120 struct scatterlist *sgl;
121 struct sg_table table;
122 struct scatterlist *prot_sgl;
123 struct sg_table prot_table;
124 /* Fast path response header iovec used when only one vec is needed */
125 struct iovec tvc_resp_iov;
126 /* Number of iovs for response */
127 unsigned int tvc_resp_iovs_cnt;
128 /* Pointer to response header iovecs if more than one is needed */
129 struct iovec *tvc_resp_iovs;
130 /* Pointer to vhost_virtqueue for the cmd */
131 struct vhost_virtqueue *tvc_vq;
132 /* The TCM I/O descriptor that is accessed via container_of() */
133 struct se_cmd tvc_se_cmd;
134 /* Sense buffer that will be mapped into outgoing status */
135 unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
136 /*
137 * Dirty write descriptors of this command.
138 */
139 struct vhost_log *tvc_log;
140 unsigned int tvc_log_num;
141 /* Completed commands list, serviced from vhost worker thread */
142 struct llist_node tvc_completion_list;
143 /* Used to track inflight cmd */
144 struct vhost_scsi_inflight *inflight;
145 };
146
147 struct vhost_scsi_nexus {
148 /* Pointer to TCM session for I_T Nexus */
149 struct se_session *tvn_se_sess;
150 };
151
152 struct vhost_scsi_tpg {
153 /* Vhost port target portal group tag for TCM */
154 u16 tport_tpgt;
155 /* Used to track number of TPG Port/Lun Links wrt to explicit I_T Nexus shutdown */
156 int tv_tpg_port_count;
157 /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
158 int tv_tpg_vhost_count;
159 /* Used for enabling T10-PI with legacy devices */
160 int tv_fabric_prot_type;
161 /* list for vhost_scsi_list */
162 struct list_head tv_tpg_list;
163 /* Used to protect access for tpg_nexus */
164 struct mutex tv_tpg_mutex;
165 /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
166 struct vhost_scsi_nexus *tpg_nexus;
167 /* Pointer back to vhost_scsi_tport */
168 struct vhost_scsi_tport *tport;
169 /* Returned by vhost_scsi_make_tpg() */
170 struct se_portal_group se_tpg;
171 /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
172 struct vhost_scsi *vhost_scsi;
173 };
174
175 struct vhost_scsi_tport {
176 /* SCSI protocol the tport is providing */
177 u8 tport_proto_id;
178 /* Binary World Wide unique Port Name for Vhost Target port */
179 u64 tport_wwpn;
180 /* ASCII formatted WWPN for Vhost Target port */
181 char tport_name[VHOST_SCSI_NAMELEN];
182 /* Returned by vhost_scsi_make_tport() */
183 struct se_wwn tport_wwn;
184 };
185
186 struct vhost_scsi_evt {
187 /* event to be sent to guest */
188 struct virtio_scsi_event event;
189 /* event list, serviced from vhost worker thread */
190 struct llist_node list;
191 };
192
193 enum {
194 VHOST_SCSI_VQ_CTL = 0,
195 VHOST_SCSI_VQ_EVT = 1,
196 VHOST_SCSI_VQ_IO = 2,
197 };
198
199 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
200 static const int vhost_scsi_bits[] = {
201 VHOST_FEATURES,
202 VIRTIO_SCSI_F_HOTPLUG,
203 VIRTIO_SCSI_F_T10_PI
204 };
205
206 #define VHOST_SCSI_FEATURES VHOST_FEATURES_U64(vhost_scsi_bits, 0)
207
208 #define VHOST_SCSI_MAX_TARGET 256
209 #define VHOST_SCSI_MAX_IO_VQ 1024
210 #define VHOST_SCSI_MAX_EVENT 128
211
212 static unsigned vhost_scsi_max_io_vqs = 128;
213 module_param_named(max_io_vqs, vhost_scsi_max_io_vqs, uint, 0644);
214 MODULE_PARM_DESC(max_io_vqs, "Set the max number of IO virtqueues a vhost scsi device can support. The default is 128. The max is 1024.");
215
216 struct vhost_scsi_virtqueue {
217 struct vhost_virtqueue vq;
218 struct vhost_scsi *vs;
219 /*
220 * Reference counting for inflight reqs, used for flush operation. At
221 * each time, one reference tracks new commands submitted, while we
222 * wait for another one to reach 0.
223 */
224 struct vhost_scsi_inflight inflights[2];
225 /*
226 * Indicate current inflight in use, protected by vq->mutex.
227 * Writers must also take dev mutex and flush under it.
228 */
229 int inflight_idx;
230 struct vhost_scsi_cmd *scsi_cmds;
231 struct sbitmap scsi_tags;
232 int max_cmds;
233 struct page **upages;
234
235 struct vhost_work completion_work;
236 struct llist_head completion_list;
237 };
238
239 struct vhost_scsi {
240 /* Protected by vhost_scsi->dev.mutex */
241 struct vhost_scsi_tpg **vs_tpg;
242 char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
243
244 struct vhost_dev dev;
245 struct vhost_scsi_virtqueue *vqs;
246 struct vhost_scsi_inflight **old_inflight;
247
248 struct vhost_work vs_event_work; /* evt injection work item */
249 struct llist_head vs_event_list; /* evt injection queue */
250
251 bool vs_events_missed; /* any missed events, protected by vq->mutex */
252 int vs_events_nr; /* num of pending events, protected by vq->mutex */
253
254 unsigned int inline_sg_cnt;
255 };
256
257 struct vhost_scsi_tmf {
258 struct vhost_work vwork;
259 struct work_struct flush_work;
260 struct vhost_scsi *vhost;
261 struct vhost_scsi_virtqueue *svq;
262
263 struct se_cmd se_cmd;
264 u8 scsi_resp;
265 struct vhost_scsi_inflight *inflight;
266 struct iovec resp_iov;
267 int in_iovs;
268 int vq_desc;
269
270 /*
271 * Dirty write descriptors of this command.
272 */
273 struct vhost_log *tmf_log;
274 unsigned int tmf_log_num;
275 };
276
277 /*
278 * Context for processing request and control queue operations.
279 */
280 struct vhost_scsi_ctx {
281 int head;
282 unsigned int out, in;
283 size_t req_size, rsp_size;
284 size_t out_size, in_size;
285 u8 *target, *lunp;
286 void *req;
287 struct iov_iter out_iter;
288 };
289
290 /*
291 * Global mutex to protect vhost_scsi TPG list for vhost IOCTLs and LIO
292 * configfs management operations.
293 */
294 static DEFINE_MUTEX(vhost_scsi_mutex);
295 static LIST_HEAD(vhost_scsi_list);
296
vhost_scsi_done_inflight(struct kref * kref)297 static void vhost_scsi_done_inflight(struct kref *kref)
298 {
299 struct vhost_scsi_inflight *inflight;
300
301 inflight = container_of(kref, struct vhost_scsi_inflight, kref);
302 complete(&inflight->comp);
303 }
304
vhost_scsi_init_inflight(struct vhost_scsi * vs,struct vhost_scsi_inflight * old_inflight[])305 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
306 struct vhost_scsi_inflight *old_inflight[])
307 {
308 struct vhost_scsi_inflight *new_inflight;
309 struct vhost_virtqueue *vq;
310 int idx, i;
311
312 for (i = 0; i < vs->dev.nvqs; i++) {
313 vq = &vs->vqs[i].vq;
314
315 mutex_lock(&vq->mutex);
316
317 /* store old inflight */
318 idx = vs->vqs[i].inflight_idx;
319 if (old_inflight)
320 old_inflight[i] = &vs->vqs[i].inflights[idx];
321
322 /* setup new inflight */
323 vs->vqs[i].inflight_idx = idx ^ 1;
324 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
325 kref_init(&new_inflight->kref);
326 init_completion(&new_inflight->comp);
327
328 mutex_unlock(&vq->mutex);
329 }
330 }
331
332 static struct vhost_scsi_inflight *
vhost_scsi_get_inflight(struct vhost_virtqueue * vq)333 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
334 {
335 struct vhost_scsi_inflight *inflight;
336 struct vhost_scsi_virtqueue *svq;
337
338 svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
339 inflight = &svq->inflights[svq->inflight_idx];
340 kref_get(&inflight->kref);
341
342 return inflight;
343 }
344
vhost_scsi_put_inflight(struct vhost_scsi_inflight * inflight)345 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
346 {
347 kref_put(&inflight->kref, vhost_scsi_done_inflight);
348 }
349
vhost_scsi_check_true(struct se_portal_group * se_tpg)350 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
351 {
352 return 1;
353 }
354
vhost_scsi_get_fabric_wwn(struct se_portal_group * se_tpg)355 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
356 {
357 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
358 struct vhost_scsi_tpg, se_tpg);
359 struct vhost_scsi_tport *tport = tpg->tport;
360
361 return &tport->tport_name[0];
362 }
363
vhost_scsi_get_tpgt(struct se_portal_group * se_tpg)364 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
365 {
366 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
367 struct vhost_scsi_tpg, se_tpg);
368 return tpg->tport_tpgt;
369 }
370
vhost_scsi_check_prot_fabric_only(struct se_portal_group * se_tpg)371 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
372 {
373 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
374 struct vhost_scsi_tpg, se_tpg);
375
376 return tpg->tv_fabric_prot_type;
377 }
378
vhost_scsi_copy_cmd_log(struct vhost_virtqueue * vq,struct vhost_scsi_cmd * cmd,struct vhost_log * log,unsigned int log_num)379 static int vhost_scsi_copy_cmd_log(struct vhost_virtqueue *vq,
380 struct vhost_scsi_cmd *cmd,
381 struct vhost_log *log,
382 unsigned int log_num)
383 {
384 if (!cmd->tvc_log)
385 cmd->tvc_log = kmalloc_objs(*cmd->tvc_log, vq->dev->iov_limit);
386
387 if (unlikely(!cmd->tvc_log)) {
388 vq_err(vq, "Failed to alloc tvc_log\n");
389 return -ENOMEM;
390 }
391
392 memcpy(cmd->tvc_log, log, sizeof(*cmd->tvc_log) * log_num);
393 cmd->tvc_log_num = log_num;
394
395 return 0;
396 }
397
vhost_scsi_log_write(struct vhost_virtqueue * vq,struct vhost_log * log,unsigned int log_num)398 static void vhost_scsi_log_write(struct vhost_virtqueue *vq,
399 struct vhost_log *log,
400 unsigned int log_num)
401 {
402 if (likely(!vhost_has_feature(vq, VHOST_F_LOG_ALL)))
403 return;
404
405 if (likely(!log_num || !log))
406 return;
407
408 /*
409 * vhost-scsi doesn't support VIRTIO_F_ACCESS_PLATFORM.
410 * No requirement for vq->iotlb case.
411 */
412 WARN_ON_ONCE(unlikely(vq->iotlb));
413 vhost_log_write(vq, log, log_num, U64_MAX, NULL, 0);
414 }
415
vhost_scsi_release_cmd_res(struct se_cmd * se_cmd)416 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
417 {
418 struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
419 struct vhost_scsi_cmd, tvc_se_cmd);
420 struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
421 struct vhost_scsi_virtqueue, vq);
422 struct vhost_scsi *vs = svq->vs;
423 struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
424 struct scatterlist *sg;
425 struct page *page;
426 int i;
427
428 if (tv_cmd->tvc_sgl_count) {
429 for_each_sgtable_sg(&tv_cmd->table, sg, i) {
430 page = sg_page(sg);
431 if (!page)
432 continue;
433
434 if (tv_cmd->copied_iov)
435 __free_page(page);
436 else
437 put_page(page);
438 }
439 kfree(tv_cmd->read_iter);
440 kfree(tv_cmd->read_iov);
441 sg_free_table_chained(&tv_cmd->table, vs->inline_sg_cnt);
442 }
443 if (tv_cmd->tvc_prot_sgl_count) {
444 for_each_sgtable_sg(&tv_cmd->prot_table, sg, i) {
445 page = sg_page(sg);
446 if (page)
447 put_page(page);
448 }
449 sg_free_table_chained(&tv_cmd->prot_table, vs->inline_sg_cnt);
450 }
451
452 if (tv_cmd->tvc_resp_iovs != &tv_cmd->tvc_resp_iov)
453 kfree(tv_cmd->tvc_resp_iovs);
454 sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
455 vhost_scsi_put_inflight(inflight);
456 }
457
vhost_scsi_release_tmf_res(struct vhost_scsi_tmf * tmf)458 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
459 {
460 struct vhost_scsi_inflight *inflight = tmf->inflight;
461
462 /*
463 * tmf->tmf_log is default NULL unless VHOST_F_LOG_ALL is set.
464 */
465 kfree(tmf->tmf_log);
466 kfree(tmf);
467 vhost_scsi_put_inflight(inflight);
468 }
469
vhost_scsi_drop_cmds(struct vhost_scsi_virtqueue * svq)470 static void vhost_scsi_drop_cmds(struct vhost_scsi_virtqueue *svq)
471 {
472 struct vhost_scsi_cmd *cmd, *t;
473 struct llist_node *llnode;
474
475 llnode = llist_del_all(&svq->completion_list);
476 llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list)
477 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
478 }
479
vhost_scsi_release_cmd(struct se_cmd * se_cmd)480 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
481 {
482 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
483 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
484 struct vhost_scsi_tmf, se_cmd);
485
486 schedule_work(&tmf->flush_work);
487 } else {
488 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
489 struct vhost_scsi_cmd, tvc_se_cmd);
490 struct vhost_scsi_virtqueue *svq = container_of(cmd->tvc_vq,
491 struct vhost_scsi_virtqueue, vq);
492
493 llist_add(&cmd->tvc_completion_list, &svq->completion_list);
494 if (!vhost_vq_work_queue(&svq->vq, &svq->completion_work))
495 vhost_scsi_drop_cmds(svq);
496 }
497 }
498
vhost_scsi_write_pending(struct se_cmd * se_cmd)499 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
500 {
501 /* Go ahead and process the write immediately */
502 target_execute_cmd(se_cmd);
503 return 0;
504 }
505
vhost_scsi_queue_data_in(struct se_cmd * se_cmd)506 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
507 {
508 transport_generic_free_cmd(se_cmd, 0);
509 return 0;
510 }
511
vhost_scsi_queue_status(struct se_cmd * se_cmd)512 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
513 {
514 transport_generic_free_cmd(se_cmd, 0);
515 return 0;
516 }
517
vhost_scsi_queue_tm_rsp(struct se_cmd * se_cmd)518 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
519 {
520 struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
521 se_cmd);
522
523 tmf->scsi_resp = se_cmd->se_tmr_req->response;
524 transport_generic_free_cmd(&tmf->se_cmd, 0);
525 }
526
vhost_scsi_aborted_task(struct se_cmd * se_cmd)527 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
528 {
529 return;
530 }
531
vhost_scsi_free_evt(struct vhost_scsi * vs,struct vhost_scsi_evt * evt)532 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
533 {
534 vs->vs_events_nr--;
535 kfree(evt);
536 }
537
538 static struct vhost_scsi_evt *
vhost_scsi_allocate_evt(struct vhost_scsi * vs,u32 event,u32 reason)539 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
540 u32 event, u32 reason)
541 {
542 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
543 struct vhost_scsi_evt *evt;
544
545 if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
546 vs->vs_events_missed = true;
547 return NULL;
548 }
549
550 evt = kzalloc_obj(*evt);
551 if (!evt) {
552 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
553 vs->vs_events_missed = true;
554 return NULL;
555 }
556
557 evt->event.event = cpu_to_vhost32(vq, event);
558 evt->event.reason = cpu_to_vhost32(vq, reason);
559 vs->vs_events_nr++;
560
561 return evt;
562 }
563
vhost_scsi_check_stop_free(struct se_cmd * se_cmd)564 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
565 {
566 return target_put_sess_cmd(se_cmd);
567 }
568
569 static void
vhost_scsi_do_evt_work(struct vhost_scsi * vs,struct vhost_scsi_evt * evt)570 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
571 {
572 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
573 struct virtio_scsi_event *event = &evt->event;
574 struct virtio_scsi_event __user *eventp;
575 struct vhost_log *vq_log;
576 unsigned int log_num;
577 unsigned out, in;
578 int head, ret;
579
580 if (!vhost_vq_get_backend(vq)) {
581 vs->vs_events_missed = true;
582 return;
583 }
584
585 again:
586 vhost_disable_notify(&vs->dev, vq);
587
588 vq_log = unlikely(vhost_has_feature(vq, VHOST_F_LOG_ALL)) ?
589 vq->log : NULL;
590
591 /*
592 * Reset 'log_num' since vhost_get_vq_desc() may reset it only
593 * after certain condition checks.
594 */
595 log_num = 0;
596
597 head = vhost_get_vq_desc(vq, vq->iov,
598 ARRAY_SIZE(vq->iov), &out, &in,
599 vq_log, &log_num);
600 if (head < 0) {
601 vs->vs_events_missed = true;
602 return;
603 }
604 if (head == vq->num) {
605 if (vhost_enable_notify(&vs->dev, vq))
606 goto again;
607 vs->vs_events_missed = true;
608 return;
609 }
610
611 if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
612 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
613 vq->iov[out].iov_len);
614 vs->vs_events_missed = true;
615 return;
616 }
617
618 if (vs->vs_events_missed) {
619 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
620 vs->vs_events_missed = false;
621 }
622
623 eventp = vq->iov[out].iov_base;
624 ret = __copy_to_user(eventp, event, sizeof(*event));
625 if (!ret)
626 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
627 else
628 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
629
630 vhost_scsi_log_write(vq, vq_log, log_num);
631 }
632
vhost_scsi_complete_events(struct vhost_scsi * vs,bool drop)633 static void vhost_scsi_complete_events(struct vhost_scsi *vs, bool drop)
634 {
635 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
636 struct vhost_scsi_evt *evt, *t;
637 struct llist_node *llnode;
638
639 mutex_lock(&vq->mutex);
640 llnode = llist_del_all(&vs->vs_event_list);
641 llist_for_each_entry_safe(evt, t, llnode, list) {
642 if (!drop)
643 vhost_scsi_do_evt_work(vs, evt);
644 vhost_scsi_free_evt(vs, evt);
645 }
646 mutex_unlock(&vq->mutex);
647 }
648
vhost_scsi_evt_work(struct vhost_work * work)649 static void vhost_scsi_evt_work(struct vhost_work *work)
650 {
651 struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
652 vs_event_work);
653 vhost_scsi_complete_events(vs, false);
654 }
655
vhost_scsi_copy_sgl_to_iov(struct vhost_scsi_cmd * cmd)656 static int vhost_scsi_copy_sgl_to_iov(struct vhost_scsi_cmd *cmd)
657 {
658 struct iov_iter *iter = cmd->read_iter;
659 struct scatterlist *sg;
660 struct page *page;
661 size_t len;
662 int i;
663
664 for_each_sgtable_sg(&cmd->table, sg, i) {
665 page = sg_page(sg);
666 if (!page)
667 continue;
668
669 len = sg->length;
670
671 if (copy_page_to_iter(page, 0, len, iter) != len) {
672 pr_err("Could not copy data while handling misaligned cmd. Error %zu\n",
673 len);
674 return -1;
675 }
676 }
677
678 return 0;
679 }
680
681 /* Fill in status and signal that we are done processing this command
682 *
683 * This is scheduled in the vhost work queue so we are called with the owner
684 * process mm and can access the vring.
685 */
vhost_scsi_complete_cmd_work(struct vhost_work * work)686 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
687 {
688 struct vhost_scsi_virtqueue *svq = container_of(work,
689 struct vhost_scsi_virtqueue, completion_work);
690 struct virtio_scsi_cmd_resp v_rsp;
691 struct vhost_scsi_cmd *cmd, *t;
692 struct llist_node *llnode;
693 struct se_cmd *se_cmd;
694 struct iov_iter iov_iter;
695 bool signal = false;
696 int ret;
697
698 llnode = llist_del_all(&svq->completion_list);
699
700 mutex_lock(&svq->vq.mutex);
701
702 llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
703 se_cmd = &cmd->tvc_se_cmd;
704
705 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
706 cmd, se_cmd->residual_count, se_cmd->scsi_status);
707 memset(&v_rsp, 0, sizeof(v_rsp));
708
709 if (cmd->read_iter && vhost_scsi_copy_sgl_to_iov(cmd)) {
710 v_rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
711 } else {
712 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq,
713 se_cmd->residual_count);
714 /* TODO is status_qualifier field needed? */
715 v_rsp.status = se_cmd->scsi_status;
716 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
717 se_cmd->scsi_sense_length);
718 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
719 se_cmd->scsi_sense_length);
720 }
721
722 iov_iter_init(&iov_iter, ITER_DEST, cmd->tvc_resp_iovs,
723 cmd->tvc_resp_iovs_cnt, sizeof(v_rsp));
724 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
725 if (likely(ret == sizeof(v_rsp))) {
726 signal = true;
727
728 vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
729 } else
730 pr_err("Faulted on virtio_scsi_cmd_resp\n");
731
732 vhost_scsi_log_write(cmd->tvc_vq, cmd->tvc_log,
733 cmd->tvc_log_num);
734
735 vhost_scsi_release_cmd_res(se_cmd);
736 }
737
738 mutex_unlock(&svq->vq.mutex);
739
740 if (signal)
741 vhost_signal(&svq->vs->dev, &svq->vq);
742 }
743
744 static struct vhost_scsi_cmd *
vhost_scsi_get_cmd(struct vhost_virtqueue * vq,u64 scsi_tag)745 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, u64 scsi_tag)
746 {
747 struct vhost_scsi_virtqueue *svq = container_of(vq,
748 struct vhost_scsi_virtqueue, vq);
749 struct vhost_scsi_cmd *cmd;
750 struct scatterlist *sgl, *prot_sgl;
751 struct vhost_log *log;
752 int tag;
753
754 tag = sbitmap_get(&svq->scsi_tags);
755 if (tag < 0) {
756 pr_warn_once("Guest sent too many cmds. Returning TASK_SET_FULL.\n");
757 return ERR_PTR(-ENOMEM);
758 }
759
760 cmd = &svq->scsi_cmds[tag];
761 sgl = cmd->sgl;
762 prot_sgl = cmd->prot_sgl;
763 log = cmd->tvc_log;
764 memset(cmd, 0, sizeof(*cmd));
765 cmd->sgl = sgl;
766 cmd->prot_sgl = prot_sgl;
767 cmd->tvc_log = log;
768 cmd->tvc_se_cmd.map_tag = tag;
769 cmd->inflight = vhost_scsi_get_inflight(vq);
770
771 return cmd;
772 }
773
vhost_scsi_revert_map_iov_to_sgl(struct iov_iter * iter,struct scatterlist * curr,struct scatterlist * end)774 static void vhost_scsi_revert_map_iov_to_sgl(struct iov_iter *iter,
775 struct scatterlist *curr,
776 struct scatterlist *end)
777 {
778 size_t revert_bytes = 0;
779 struct page *page;
780
781 while (curr != end) {
782 page = sg_page(curr);
783
784 if (page) {
785 put_page(page);
786 revert_bytes += curr->length;
787 }
788 /* Clear so we can re-use it for the copy path */
789 sg_set_page(curr, NULL, 0, 0);
790 curr = sg_next(curr);
791 }
792 iov_iter_revert(iter, revert_bytes);
793 }
794
795 /*
796 * Map a user memory range into a scatterlist
797 *
798 * Returns the number of scatterlist entries used or -errno on error.
799 */
800 static int
vhost_scsi_map_to_sgl(struct vhost_scsi_cmd * cmd,struct iov_iter * iter,struct sg_table * sg_table,struct scatterlist ** sgl,bool is_prot)801 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
802 struct iov_iter *iter,
803 struct sg_table *sg_table,
804 struct scatterlist **sgl,
805 bool is_prot)
806 {
807 struct vhost_scsi_virtqueue *svq = container_of(cmd->tvc_vq,
808 struct vhost_scsi_virtqueue, vq);
809 struct page **pages = svq->upages;
810 struct scatterlist *sg = *sgl;
811 ssize_t bytes;
812 size_t offset;
813 unsigned int n, npages = 0;
814
815 bytes = iov_iter_get_pages2(iter, pages, LONG_MAX,
816 VHOST_SCSI_PREALLOC_UPAGES, &offset);
817 /* No pages were pinned */
818 if (bytes <= 0)
819 return bytes < 0 ? bytes : -EFAULT;
820
821 while (bytes) {
822 n = min_t(unsigned int, PAGE_SIZE - offset, bytes);
823 /*
824 * The block layer requires bios/requests to be a multiple of
825 * 512 bytes, but Windows can send us vecs that are misaligned.
826 * This can result in bios and later requests with misaligned
827 * sizes if we have to break up a cmd/scatterlist into multiple
828 * bios.
829 *
830 * We currently only break up a command into multiple bios if
831 * we hit the vec/seg limit, so check if our sgl_count is
832 * greater than the max and if a vec in the cmd has a
833 * misaligned offset/size.
834 */
835 if (!is_prot &&
836 (offset & (SECTOR_SIZE - 1) || n & (SECTOR_SIZE - 1)) &&
837 cmd->tvc_sgl_count > BIO_MAX_VECS) {
838 WARN_ONCE(true,
839 "vhost-scsi detected misaligned IO. Performance may be degraded.");
840 goto revert_iter_get_pages;
841 }
842
843 sg_set_page(sg, pages[npages++], n, offset);
844 sg = sg_next(sg);
845 bytes -= n;
846 offset = 0;
847 }
848
849 *sgl = sg;
850 return npages;
851
852 revert_iter_get_pages:
853 vhost_scsi_revert_map_iov_to_sgl(iter, *sgl, sg);
854
855 iov_iter_revert(iter, bytes);
856 while (bytes) {
857 n = min_t(unsigned int, PAGE_SIZE, bytes);
858
859 put_page(pages[npages++]);
860 bytes -= n;
861 }
862
863 return -EINVAL;
864 }
865
866 static int
vhost_scsi_calc_sgls(struct iov_iter * iter,size_t bytes,int max_sgls)867 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
868 {
869 int sgl_count = 0;
870
871 if (!iter || !iter_iov(iter)) {
872 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
873 " present\n", __func__, bytes);
874 return -EINVAL;
875 }
876
877 sgl_count = iov_iter_npages(iter, 0xffff);
878 if (sgl_count > max_sgls) {
879 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
880 " max_sgls: %d\n", __func__, sgl_count, max_sgls);
881 return -EINVAL;
882 }
883 return sgl_count;
884 }
885
886 static int
vhost_scsi_copy_iov_to_sgl(struct vhost_scsi_cmd * cmd,struct iov_iter * iter,struct sg_table * sg_table,int sg_count,int data_dir)887 vhost_scsi_copy_iov_to_sgl(struct vhost_scsi_cmd *cmd, struct iov_iter *iter,
888 struct sg_table *sg_table, int sg_count,
889 int data_dir)
890 {
891 size_t len = iov_iter_count(iter);
892 unsigned int nbytes = 0;
893 struct scatterlist *sg;
894 struct page *page;
895 int i, ret;
896
897 if (data_dir == DMA_FROM_DEVICE) {
898 cmd->read_iter = kzalloc_obj(*cmd->read_iter);
899 if (!cmd->read_iter)
900 return -ENOMEM;
901
902 cmd->read_iov = dup_iter(cmd->read_iter, iter, GFP_KERNEL);
903 if (!cmd->read_iov) {
904 ret = -ENOMEM;
905 goto free_iter;
906 }
907 }
908
909 for_each_sgtable_sg(sg_table, sg, i) {
910 page = alloc_page(GFP_KERNEL);
911 if (!page) {
912 ret = -ENOMEM;
913 goto err;
914 }
915
916 nbytes = min_t(unsigned int, PAGE_SIZE, len);
917 sg_set_page(sg, page, nbytes, 0);
918
919 if (data_dir == DMA_TO_DEVICE &&
920 copy_page_from_iter(page, 0, nbytes, iter) != nbytes) {
921 ret = -EFAULT;
922 goto err;
923 }
924
925 len -= nbytes;
926 }
927
928 cmd->copied_iov = 1;
929 return 0;
930
931 err:
932 pr_err("Could not read %u bytes while handling misaligned cmd\n",
933 nbytes);
934
935 for_each_sgtable_sg(sg_table, sg, i) {
936 page = sg_page(sg);
937 if (page)
938 __free_page(page);
939 }
940 kfree(cmd->read_iov);
941 free_iter:
942 kfree(cmd->read_iter);
943 return ret;
944 }
945
946 static int
vhost_scsi_map_iov_to_sgl(struct vhost_scsi_cmd * cmd,struct iov_iter * iter,struct sg_table * sg_table,int sg_count,bool is_prot)947 vhost_scsi_map_iov_to_sgl(struct vhost_scsi_cmd *cmd, struct iov_iter *iter,
948 struct sg_table *sg_table, int sg_count, bool is_prot)
949 {
950 struct scatterlist *sg = sg_table->sgl;
951 int ret;
952
953 while (iov_iter_count(iter)) {
954 ret = vhost_scsi_map_to_sgl(cmd, iter, sg_table, &sg, is_prot);
955 if (ret < 0) {
956 vhost_scsi_revert_map_iov_to_sgl(iter, sg_table->sgl,
957 sg);
958 return ret;
959 }
960 }
961
962 return 0;
963 }
964
965 static int
vhost_scsi_mapal(struct vhost_scsi * vs,struct vhost_scsi_cmd * cmd,size_t prot_bytes,struct iov_iter * prot_iter,size_t data_bytes,struct iov_iter * data_iter,int data_dir)966 vhost_scsi_mapal(struct vhost_scsi *vs, struct vhost_scsi_cmd *cmd,
967 size_t prot_bytes, struct iov_iter *prot_iter,
968 size_t data_bytes, struct iov_iter *data_iter, int data_dir)
969 {
970 int sgl_count, ret;
971
972 if (prot_bytes) {
973 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
974 VHOST_SCSI_PREALLOC_PROT_SGLS);
975 cmd->prot_table.sgl = cmd->prot_sgl;
976 ret = sg_alloc_table_chained(&cmd->prot_table, sgl_count,
977 cmd->prot_table.sgl,
978 vs->inline_sg_cnt);
979 if (ret)
980 return ret;
981
982 cmd->tvc_prot_sgl_count = sgl_count;
983 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
984 cmd->prot_table.sgl, cmd->tvc_prot_sgl_count);
985
986 ret = vhost_scsi_map_iov_to_sgl(cmd, prot_iter,
987 &cmd->prot_table,
988 cmd->tvc_prot_sgl_count, true);
989 if (ret < 0) {
990 sg_free_table_chained(&cmd->prot_table,
991 vs->inline_sg_cnt);
992 cmd->tvc_prot_sgl_count = 0;
993 return ret;
994 }
995 }
996 sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
997 VHOST_SCSI_PREALLOC_SGLS);
998 if (sgl_count < 0)
999 return sgl_count;
1000
1001 cmd->table.sgl = cmd->sgl;
1002 ret = sg_alloc_table_chained(&cmd->table, sgl_count, cmd->table.sgl,
1003 vs->inline_sg_cnt);
1004 if (ret)
1005 return ret;
1006
1007 cmd->tvc_sgl_count = sgl_count;
1008 pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
1009 cmd->table.sgl, cmd->tvc_sgl_count);
1010
1011 ret = vhost_scsi_map_iov_to_sgl(cmd, data_iter, &cmd->table,
1012 cmd->tvc_sgl_count, false);
1013 if (ret == -EINVAL)
1014 ret = vhost_scsi_copy_iov_to_sgl(cmd, data_iter, &cmd->table,
1015 cmd->tvc_sgl_count, data_dir);
1016 if (ret < 0) {
1017 sg_free_table_chained(&cmd->table, vs->inline_sg_cnt);
1018 cmd->tvc_sgl_count = 0;
1019 return ret;
1020 }
1021 return 0;
1022 }
1023
vhost_scsi_to_tcm_attr(int attr)1024 static int vhost_scsi_to_tcm_attr(int attr)
1025 {
1026 switch (attr) {
1027 case VIRTIO_SCSI_S_SIMPLE:
1028 return TCM_SIMPLE_TAG;
1029 case VIRTIO_SCSI_S_ORDERED:
1030 return TCM_ORDERED_TAG;
1031 case VIRTIO_SCSI_S_HEAD:
1032 return TCM_HEAD_TAG;
1033 case VIRTIO_SCSI_S_ACA:
1034 return TCM_ACA_TAG;
1035 default:
1036 break;
1037 }
1038 return TCM_SIMPLE_TAG;
1039 }
1040
vhost_scsi_target_queue_cmd(struct vhost_scsi_nexus * nexus,struct vhost_scsi_cmd * cmd,unsigned char * cdb,u16 lun,int task_attr,int data_dir,u32 exp_data_len)1041 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_nexus *nexus,
1042 struct vhost_scsi_cmd *cmd,
1043 unsigned char *cdb, u16 lun,
1044 int task_attr, int data_dir,
1045 u32 exp_data_len)
1046 {
1047 struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
1048 struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
1049
1050 /* FIXME: BIDI operation */
1051 if (cmd->tvc_sgl_count) {
1052 sg_ptr = cmd->table.sgl;
1053
1054 if (cmd->tvc_prot_sgl_count)
1055 sg_prot_ptr = cmd->prot_table.sgl;
1056 else
1057 se_cmd->prot_pto = true;
1058 } else {
1059 sg_ptr = NULL;
1060 }
1061
1062 se_cmd->tag = 0;
1063 target_init_cmd(se_cmd, nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
1064 lun, exp_data_len, vhost_scsi_to_tcm_attr(task_attr),
1065 data_dir, TARGET_SCF_ACK_KREF);
1066
1067 if (target_submit_prep(se_cmd, cdb, sg_ptr,
1068 cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
1069 cmd->tvc_prot_sgl_count, GFP_KERNEL))
1070 return;
1071
1072 target_submit(se_cmd);
1073 }
1074
1075 static void
vhost_scsi_send_status(struct vhost_scsi * vs,struct vhost_virtqueue * vq,struct vhost_scsi_ctx * vc,u8 status)1076 vhost_scsi_send_status(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1077 struct vhost_scsi_ctx *vc, u8 status)
1078 {
1079 struct virtio_scsi_cmd_resp rsp;
1080 struct iov_iter iov_iter;
1081 int ret;
1082
1083 memset(&rsp, 0, sizeof(rsp));
1084 rsp.status = status;
1085
1086 iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[vc->out], vc->in,
1087 sizeof(rsp));
1088
1089 ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1090
1091 if (likely(ret == sizeof(rsp)))
1092 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1093 else
1094 pr_err("Faulted on virtio_scsi_cmd_resp\n");
1095 }
1096
1097 #define TYPE_IO_CMD 0
1098 #define TYPE_CTRL_TMF 1
1099 #define TYPE_CTRL_AN 2
1100
1101 static void
vhost_scsi_send_bad_target(struct vhost_scsi * vs,struct vhost_virtqueue * vq,struct vhost_scsi_ctx * vc,int type)1102 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
1103 struct vhost_virtqueue *vq,
1104 struct vhost_scsi_ctx *vc, int type)
1105 {
1106 union {
1107 struct virtio_scsi_cmd_resp cmd;
1108 struct virtio_scsi_ctrl_tmf_resp tmf;
1109 struct virtio_scsi_ctrl_an_resp an;
1110 } rsp;
1111 struct iov_iter iov_iter;
1112 size_t rsp_size;
1113 int ret;
1114
1115 memset(&rsp, 0, sizeof(rsp));
1116
1117 if (type == TYPE_IO_CMD) {
1118 rsp_size = sizeof(struct virtio_scsi_cmd_resp);
1119 rsp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
1120 } else if (type == TYPE_CTRL_TMF) {
1121 rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1122 rsp.tmf.response = VIRTIO_SCSI_S_BAD_TARGET;
1123 } else {
1124 rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1125 rsp.an.response = VIRTIO_SCSI_S_BAD_TARGET;
1126 }
1127
1128 iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[vc->out], vc->in,
1129 rsp_size);
1130
1131 ret = copy_to_iter(&rsp, rsp_size, &iov_iter);
1132
1133 if (likely(ret == rsp_size))
1134 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1135 else
1136 pr_err("Faulted on virtio scsi type=%d\n", type);
1137 }
1138
1139 static int
vhost_scsi_get_desc(struct vhost_scsi * vs,struct vhost_virtqueue * vq,struct vhost_scsi_ctx * vc,struct vhost_log * log,unsigned int * log_num)1140 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1141 struct vhost_scsi_ctx *vc,
1142 struct vhost_log *log, unsigned int *log_num)
1143 {
1144 int ret = -ENXIO;
1145
1146 if (likely(log_num))
1147 *log_num = 0;
1148
1149 vc->head = vhost_get_vq_desc(vq, vq->iov,
1150 ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
1151 log, log_num);
1152
1153 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
1154 vc->head, vc->out, vc->in);
1155
1156 /* On error, stop handling until the next kick. */
1157 if (unlikely(vc->head < 0))
1158 goto done;
1159
1160 /* Nothing new? Wait for eventfd to tell us they refilled. */
1161 if (vc->head == vq->num) {
1162 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
1163 vhost_disable_notify(&vs->dev, vq);
1164 ret = -EAGAIN;
1165 }
1166 goto done;
1167 }
1168
1169 /*
1170 * Get the size of request and response buffers.
1171 * FIXME: Not correct for BIDI operation
1172 */
1173 vc->out_size = iov_length(vq->iov, vc->out);
1174 vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
1175
1176 /*
1177 * Copy over the virtio-scsi request header, which for a
1178 * ANY_LAYOUT enabled guest may span multiple iovecs, or a
1179 * single iovec may contain both the header + outgoing
1180 * WRITE payloads.
1181 *
1182 * copy_from_iter() will advance out_iter, so that it will
1183 * point at the start of the outgoing WRITE payload, if
1184 * DMA_TO_DEVICE is set.
1185 */
1186 iov_iter_init(&vc->out_iter, ITER_SOURCE, vq->iov, vc->out, vc->out_size);
1187 ret = 0;
1188
1189 done:
1190 return ret;
1191 }
1192
1193 static int
vhost_scsi_chk_size(struct vhost_virtqueue * vq,struct vhost_scsi_ctx * vc)1194 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
1195 {
1196 if (unlikely(vc->in_size < vc->rsp_size)) {
1197 vq_err(vq,
1198 "Response buf too small, need min %zu bytes got %zu",
1199 vc->rsp_size, vc->in_size);
1200 return -EINVAL;
1201 } else if (unlikely(vc->out_size < vc->req_size)) {
1202 vq_err(vq,
1203 "Request buf too small, need min %zu bytes got %zu",
1204 vc->req_size, vc->out_size);
1205 return -EIO;
1206 }
1207
1208 return 0;
1209 }
1210
1211 static int
vhost_scsi_get_req(struct vhost_virtqueue * vq,struct vhost_scsi_ctx * vc,struct vhost_scsi_tpg ** tpgp)1212 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
1213 struct vhost_scsi_tpg **tpgp)
1214 {
1215 int ret = -EIO;
1216
1217 if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
1218 &vc->out_iter))) {
1219 vq_err(vq, "Faulted on copy_from_iter_full\n");
1220 } else if (unlikely(*vc->lunp != 1)) {
1221 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
1222 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
1223 } else {
1224 struct vhost_scsi_tpg **vs_tpg, *tpg = NULL;
1225
1226 if (vc->target) {
1227 /* validated at handler entry */
1228 vs_tpg = vhost_vq_get_backend(vq);
1229 tpg = READ_ONCE(vs_tpg[*vc->target]);
1230 if (unlikely(!tpg))
1231 goto out;
1232 }
1233
1234 if (tpgp)
1235 *tpgp = tpg;
1236 ret = 0;
1237 }
1238 out:
1239 return ret;
1240 }
1241
1242 static int
vhost_scsi_setup_resp_iovs(struct vhost_scsi_cmd * cmd,struct iovec * in_iovs,unsigned int in_iovs_cnt)1243 vhost_scsi_setup_resp_iovs(struct vhost_scsi_cmd *cmd, struct iovec *in_iovs,
1244 unsigned int in_iovs_cnt)
1245 {
1246 int i, cnt;
1247
1248 if (!in_iovs_cnt)
1249 return 0;
1250 /*
1251 * Initiators normally just put the virtio_scsi_cmd_resp in the first
1252 * iov, but just in case they wedged in some data with it we check for
1253 * greater than or equal to the response struct.
1254 */
1255 if (in_iovs[0].iov_len >= sizeof(struct virtio_scsi_cmd_resp)) {
1256 cmd->tvc_resp_iovs = &cmd->tvc_resp_iov;
1257 cmd->tvc_resp_iovs_cnt = 1;
1258 } else {
1259 /*
1260 * Legacy descriptor layouts didn't specify that we must put
1261 * the entire response in one iov. Worst case we have a
1262 * iov per byte.
1263 */
1264 cnt = min(VHOST_SCSI_MAX_RESP_IOVS, in_iovs_cnt);
1265 cmd->tvc_resp_iovs = kzalloc_objs(struct iovec, cnt);
1266 if (!cmd->tvc_resp_iovs)
1267 return -ENOMEM;
1268
1269 cmd->tvc_resp_iovs_cnt = cnt;
1270 }
1271
1272 for (i = 0; i < cmd->tvc_resp_iovs_cnt; i++)
1273 cmd->tvc_resp_iovs[i] = in_iovs[i];
1274
1275 return 0;
1276 }
1277
vhost_buf_to_lun(u8 * lun_buf)1278 static u16 vhost_buf_to_lun(u8 *lun_buf)
1279 {
1280 return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
1281 }
1282
1283 static void
vhost_scsi_handle_vq(struct vhost_scsi * vs,struct vhost_virtqueue * vq)1284 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1285 {
1286 struct vhost_scsi_tpg **vs_tpg, *tpg;
1287 struct virtio_scsi_cmd_req v_req;
1288 struct virtio_scsi_cmd_req_pi v_req_pi;
1289 struct vhost_scsi_nexus *nexus;
1290 struct vhost_scsi_ctx vc;
1291 struct vhost_scsi_cmd *cmd;
1292 struct iov_iter in_iter, prot_iter, data_iter;
1293 u64 tag;
1294 u32 exp_data_len, data_direction;
1295 int ret, prot_bytes, c = 0;
1296 u16 lun;
1297 u8 task_attr;
1298 bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
1299 u8 *cdb;
1300 struct vhost_log *vq_log;
1301 unsigned int log_num;
1302
1303 mutex_lock(&vq->mutex);
1304 /*
1305 * We can handle the vq only after the endpoint is setup by calling the
1306 * VHOST_SCSI_SET_ENDPOINT ioctl.
1307 */
1308 vs_tpg = vhost_vq_get_backend(vq);
1309 if (!vs_tpg)
1310 goto out;
1311
1312 memset(&vc, 0, sizeof(vc));
1313 vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
1314
1315 vhost_disable_notify(&vs->dev, vq);
1316
1317 vq_log = unlikely(vhost_has_feature(vq, VHOST_F_LOG_ALL)) ?
1318 vq->log : NULL;
1319
1320 do {
1321 ret = vhost_scsi_get_desc(vs, vq, &vc, vq_log, &log_num);
1322 if (ret)
1323 goto err;
1324
1325 /*
1326 * Setup pointers and values based upon different virtio-scsi
1327 * request header if T10_PI is enabled in KVM guest.
1328 */
1329 if (t10_pi) {
1330 vc.req = &v_req_pi;
1331 vc.req_size = sizeof(v_req_pi);
1332 vc.lunp = &v_req_pi.lun[0];
1333 vc.target = &v_req_pi.lun[1];
1334 } else {
1335 vc.req = &v_req;
1336 vc.req_size = sizeof(v_req);
1337 vc.lunp = &v_req.lun[0];
1338 vc.target = &v_req.lun[1];
1339 }
1340
1341 /*
1342 * Validate the size of request and response buffers.
1343 * Check for a sane response buffer so we can report
1344 * early errors back to the guest.
1345 */
1346 ret = vhost_scsi_chk_size(vq, &vc);
1347 if (ret)
1348 goto err;
1349
1350 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1351 if (ret)
1352 goto err;
1353
1354 ret = -EIO; /* bad target on any error from here on */
1355
1356 /*
1357 * Determine data_direction by calculating the total outgoing
1358 * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
1359 * response headers respectively.
1360 *
1361 * For DMA_TO_DEVICE this is out_iter, which is already pointing
1362 * to the right place.
1363 *
1364 * For DMA_FROM_DEVICE, the iovec will be just past the end
1365 * of the virtio-scsi response header in either the same
1366 * or immediately following iovec.
1367 *
1368 * Any associated T10_PI bytes for the outgoing / incoming
1369 * payloads are included in calculation of exp_data_len here.
1370 */
1371 prot_bytes = 0;
1372
1373 if (vc.out_size > vc.req_size) {
1374 data_direction = DMA_TO_DEVICE;
1375 exp_data_len = vc.out_size - vc.req_size;
1376 data_iter = vc.out_iter;
1377 } else if (vc.in_size > vc.rsp_size) {
1378 data_direction = DMA_FROM_DEVICE;
1379 exp_data_len = vc.in_size - vc.rsp_size;
1380
1381 iov_iter_init(&in_iter, ITER_DEST, &vq->iov[vc.out], vc.in,
1382 vc.rsp_size + exp_data_len);
1383 iov_iter_advance(&in_iter, vc.rsp_size);
1384 data_iter = in_iter;
1385 } else {
1386 data_direction = DMA_NONE;
1387 exp_data_len = 0;
1388 }
1389 /*
1390 * If T10_PI header + payload is present, setup prot_iter values
1391 * and recalculate data_iter for vhost_scsi_mapal() mapping to
1392 * host scatterlists via get_user_pages_fast().
1393 */
1394 if (t10_pi) {
1395 if (v_req_pi.pi_bytesout) {
1396 if (data_direction != DMA_TO_DEVICE) {
1397 vq_err(vq, "Received non zero pi_bytesout,"
1398 " but wrong data_direction\n");
1399 goto err;
1400 }
1401 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1402 } else if (v_req_pi.pi_bytesin) {
1403 if (data_direction != DMA_FROM_DEVICE) {
1404 vq_err(vq, "Received non zero pi_bytesin,"
1405 " but wrong data_direction\n");
1406 goto err;
1407 }
1408 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1409 }
1410 /*
1411 * Set prot_iter to data_iter and truncate it to
1412 * prot_bytes, and advance data_iter past any
1413 * preceding prot_bytes that may be present.
1414 *
1415 * Also fix up the exp_data_len to reflect only the
1416 * actual data payload length.
1417 */
1418 if (prot_bytes) {
1419 exp_data_len -= prot_bytes;
1420 prot_iter = data_iter;
1421 iov_iter_truncate(&prot_iter, prot_bytes);
1422 iov_iter_advance(&data_iter, prot_bytes);
1423 }
1424 tag = vhost64_to_cpu(vq, v_req_pi.tag);
1425 task_attr = v_req_pi.task_attr;
1426 cdb = &v_req_pi.cdb[0];
1427 lun = vhost_buf_to_lun(v_req_pi.lun);
1428 } else {
1429 tag = vhost64_to_cpu(vq, v_req.tag);
1430 task_attr = v_req.task_attr;
1431 cdb = &v_req.cdb[0];
1432 lun = vhost_buf_to_lun(v_req.lun);
1433 }
1434 /*
1435 * Check that the received CDB size does not exceeded our
1436 * hardcoded max for vhost-scsi, then get a pre-allocated
1437 * cmd descriptor for the new virtio-scsi tag.
1438 *
1439 * TODO what if cdb was too small for varlen cdb header?
1440 */
1441 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1442 vq_err(vq, "Received SCSI CDB with command_size: %d that"
1443 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1444 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1445 goto err;
1446 }
1447
1448 nexus = tpg->tpg_nexus;
1449 if (!nexus) {
1450 vq_err(vq, "Unable to locate active struct vhost_scsi_nexus\n");
1451 ret = -EIO;
1452 goto err;
1453 }
1454
1455 cmd = vhost_scsi_get_cmd(vq, tag);
1456 if (IS_ERR(cmd)) {
1457 ret = PTR_ERR(cmd);
1458 vq_err(vq, "vhost_scsi_get_tag failed %d\n", ret);
1459 goto err;
1460 }
1461 cmd->tvc_vq = vq;
1462
1463 ret = vhost_scsi_setup_resp_iovs(cmd, &vq->iov[vc.out], vc.in);
1464 if (ret) {
1465 vq_err(vq, "Failed to alloc recv iovs\n");
1466 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1467 goto err;
1468 }
1469
1470 if (unlikely(vq_log && log_num)) {
1471 ret = vhost_scsi_copy_cmd_log(vq, cmd, vq_log, log_num);
1472 if (unlikely(ret)) {
1473 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1474 goto err;
1475 }
1476 }
1477
1478 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1479 cdb[0], lun);
1480 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1481 " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1482
1483 if (data_direction != DMA_NONE) {
1484 ret = vhost_scsi_mapal(vs, cmd, prot_bytes, &prot_iter,
1485 exp_data_len, &data_iter,
1486 data_direction);
1487 if (unlikely(ret)) {
1488 vq_err(vq, "Failed to map iov to sgl\n");
1489 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1490 goto err;
1491 }
1492 }
1493 /*
1494 * Save the descriptor from vhost_get_vq_desc() to be used to
1495 * complete the virtio-scsi request in TCM callback context via
1496 * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1497 */
1498 cmd->tvc_vq_desc = vc.head;
1499 vhost_scsi_target_queue_cmd(nexus, cmd, cdb, lun, task_attr,
1500 data_direction,
1501 exp_data_len + prot_bytes);
1502 ret = 0;
1503 err:
1504 /*
1505 * ENXIO: No more requests, or read error, wait for next kick
1506 * EINVAL: Invalid response buffer, drop the request
1507 * EIO: Respond with bad target
1508 * EAGAIN: Pending request
1509 * ENOMEM: Could not allocate resources for request
1510 */
1511 if (ret == -ENXIO)
1512 break;
1513 else if (ret == -EIO) {
1514 vhost_scsi_send_bad_target(vs, vq, &vc, TYPE_IO_CMD);
1515 vhost_scsi_log_write(vq, vq_log, log_num);
1516 } else if (ret == -ENOMEM) {
1517 vhost_scsi_send_status(vs, vq, &vc,
1518 SAM_STAT_TASK_SET_FULL);
1519 vhost_scsi_log_write(vq, vq_log, log_num);
1520 }
1521 } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1522 out:
1523 mutex_unlock(&vq->mutex);
1524 }
1525
1526 static void
vhost_scsi_send_tmf_resp(struct vhost_scsi * vs,struct vhost_virtqueue * vq,int in_iovs,int vq_desc,struct iovec * resp_iov,int tmf_resp_code)1527 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1528 int in_iovs, int vq_desc, struct iovec *resp_iov,
1529 int tmf_resp_code)
1530 {
1531 struct virtio_scsi_ctrl_tmf_resp rsp;
1532 struct iov_iter iov_iter;
1533 int ret;
1534
1535 pr_debug("%s\n", __func__);
1536 memset(&rsp, 0, sizeof(rsp));
1537 rsp.response = tmf_resp_code;
1538
1539 iov_iter_init(&iov_iter, ITER_DEST, resp_iov, in_iovs, sizeof(rsp));
1540
1541 ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1542 if (likely(ret == sizeof(rsp)))
1543 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1544 else
1545 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1546 }
1547
vhost_scsi_tmf_resp_work(struct vhost_work * work)1548 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1549 {
1550 struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1551 vwork);
1552 int resp_code;
1553
1554 if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1555 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1556 else
1557 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1558
1559 mutex_lock(&tmf->svq->vq.mutex);
1560 vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1561 tmf->vq_desc, &tmf->resp_iov, resp_code);
1562 vhost_scsi_log_write(&tmf->svq->vq, tmf->tmf_log,
1563 tmf->tmf_log_num);
1564 mutex_unlock(&tmf->svq->vq.mutex);
1565
1566 vhost_scsi_release_tmf_res(tmf);
1567 }
1568
vhost_scsi_tmf_flush_work(struct work_struct * work)1569 static void vhost_scsi_tmf_flush_work(struct work_struct *work)
1570 {
1571 struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1572 flush_work);
1573 struct vhost_virtqueue *vq = &tmf->svq->vq;
1574 /*
1575 * Make sure we have sent responses for other commands before we
1576 * send our response.
1577 */
1578 vhost_dev_flush(vq->dev);
1579 if (!vhost_vq_work_queue(vq, &tmf->vwork))
1580 vhost_scsi_release_tmf_res(tmf);
1581 }
1582
1583 static void
vhost_scsi_handle_tmf(struct vhost_scsi * vs,struct vhost_scsi_tpg * tpg,struct vhost_virtqueue * vq,struct virtio_scsi_ctrl_tmf_req * vtmf,struct vhost_scsi_ctx * vc,struct vhost_log * log,unsigned int log_num)1584 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1585 struct vhost_virtqueue *vq,
1586 struct virtio_scsi_ctrl_tmf_req *vtmf,
1587 struct vhost_scsi_ctx *vc,
1588 struct vhost_log *log, unsigned int log_num)
1589 {
1590 struct vhost_scsi_virtqueue *svq = container_of(vq,
1591 struct vhost_scsi_virtqueue, vq);
1592 struct vhost_scsi_tmf *tmf;
1593
1594 if (vhost32_to_cpu(vq, vtmf->subtype) !=
1595 VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1596 goto send_reject;
1597
1598 if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1599 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1600 goto send_reject;
1601 }
1602
1603 tmf = kzalloc_obj(*tmf);
1604 if (!tmf)
1605 goto send_reject;
1606
1607 INIT_WORK(&tmf->flush_work, vhost_scsi_tmf_flush_work);
1608 vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
1609 tmf->vhost = vs;
1610 tmf->svq = svq;
1611 tmf->resp_iov = vq->iov[vc->out];
1612 tmf->vq_desc = vc->head;
1613 tmf->in_iovs = vc->in;
1614 tmf->inflight = vhost_scsi_get_inflight(vq);
1615
1616 if (unlikely(log && log_num)) {
1617 tmf->tmf_log = kmalloc_objs(*tmf->tmf_log, log_num);
1618 if (tmf->tmf_log) {
1619 memcpy(tmf->tmf_log, log, sizeof(*tmf->tmf_log) * log_num);
1620 tmf->tmf_log_num = log_num;
1621 } else {
1622 pr_err("vhost_scsi tmf log allocation error\n");
1623 vhost_scsi_release_tmf_res(tmf);
1624 goto send_reject;
1625 }
1626 }
1627
1628 if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1629 vhost_buf_to_lun(vtmf->lun), NULL,
1630 TMR_LUN_RESET, GFP_KERNEL, 0,
1631 TARGET_SCF_ACK_KREF) < 0) {
1632 vhost_scsi_release_tmf_res(tmf);
1633 goto send_reject;
1634 }
1635
1636 return;
1637
1638 send_reject:
1639 vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1640 VIRTIO_SCSI_S_FUNCTION_REJECTED);
1641 vhost_scsi_log_write(vq, log, log_num);
1642 }
1643
1644 static void
vhost_scsi_send_an_resp(struct vhost_scsi * vs,struct vhost_virtqueue * vq,struct vhost_scsi_ctx * vc)1645 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1646 struct vhost_virtqueue *vq,
1647 struct vhost_scsi_ctx *vc)
1648 {
1649 struct virtio_scsi_ctrl_an_resp rsp;
1650 struct iov_iter iov_iter;
1651 int ret;
1652
1653 pr_debug("%s\n", __func__);
1654 memset(&rsp, 0, sizeof(rsp)); /* event_actual = 0 */
1655 rsp.response = VIRTIO_SCSI_S_OK;
1656
1657 iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[vc->out], vc->in, sizeof(rsp));
1658
1659 ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1660 if (likely(ret == sizeof(rsp)))
1661 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1662 else
1663 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1664 }
1665
1666 static void
vhost_scsi_ctl_handle_vq(struct vhost_scsi * vs,struct vhost_virtqueue * vq)1667 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1668 {
1669 struct vhost_scsi_tpg *tpg;
1670 union {
1671 __virtio32 type;
1672 struct virtio_scsi_ctrl_an_req an;
1673 struct virtio_scsi_ctrl_tmf_req tmf;
1674 } v_req;
1675 struct vhost_scsi_ctx vc;
1676 size_t typ_size;
1677 int ret, c = 0;
1678 struct vhost_log *vq_log;
1679 unsigned int log_num;
1680
1681 mutex_lock(&vq->mutex);
1682 /*
1683 * We can handle the vq only after the endpoint is setup by calling the
1684 * VHOST_SCSI_SET_ENDPOINT ioctl.
1685 */
1686 if (!vhost_vq_get_backend(vq))
1687 goto out;
1688
1689 memset(&vc, 0, sizeof(vc));
1690
1691 vhost_disable_notify(&vs->dev, vq);
1692
1693 vq_log = unlikely(vhost_has_feature(vq, VHOST_F_LOG_ALL)) ?
1694 vq->log : NULL;
1695
1696 do {
1697 ret = vhost_scsi_get_desc(vs, vq, &vc, vq_log, &log_num);
1698 if (ret)
1699 goto err;
1700
1701 /*
1702 * Get the request type first in order to setup
1703 * other parameters dependent on the type.
1704 */
1705 vc.req = &v_req.type;
1706 typ_size = sizeof(v_req.type);
1707
1708 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1709 &vc.out_iter))) {
1710 vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1711 /*
1712 * The size of the response buffer depends on the
1713 * request type and must be validated against it.
1714 * Since the request type is not known, don't send
1715 * a response.
1716 */
1717 continue;
1718 }
1719
1720 switch (vhost32_to_cpu(vq, v_req.type)) {
1721 case VIRTIO_SCSI_T_TMF:
1722 vc.req = &v_req.tmf;
1723 vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1724 vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1725 vc.lunp = &v_req.tmf.lun[0];
1726 vc.target = &v_req.tmf.lun[1];
1727 break;
1728 case VIRTIO_SCSI_T_AN_QUERY:
1729 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1730 vc.req = &v_req.an;
1731 vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1732 vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1733 vc.lunp = &v_req.an.lun[0];
1734 vc.target = NULL;
1735 break;
1736 default:
1737 vq_err(vq, "Unknown control request %d", v_req.type);
1738 continue;
1739 }
1740
1741 /*
1742 * Validate the size of request and response buffers.
1743 * Check for a sane response buffer so we can report
1744 * early errors back to the guest.
1745 */
1746 ret = vhost_scsi_chk_size(vq, &vc);
1747 if (ret)
1748 goto err;
1749
1750 /*
1751 * Get the rest of the request now that its size is known.
1752 */
1753 vc.req += typ_size;
1754 vc.req_size -= typ_size;
1755
1756 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1757 if (ret)
1758 goto err;
1759
1760 if (v_req.type == VIRTIO_SCSI_T_TMF)
1761 vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc,
1762 vq_log, log_num);
1763 else {
1764 vhost_scsi_send_an_resp(vs, vq, &vc);
1765 vhost_scsi_log_write(vq, vq_log, log_num);
1766 }
1767 err:
1768 /*
1769 * ENXIO: No more requests, or read error, wait for next kick
1770 * EINVAL: Invalid response buffer, drop the request
1771 * EIO: Respond with bad target
1772 * EAGAIN: Pending request
1773 */
1774 if (ret == -ENXIO)
1775 break;
1776 else if (ret == -EIO) {
1777 vhost_scsi_send_bad_target(vs, vq, &vc,
1778 v_req.type == VIRTIO_SCSI_T_TMF ?
1779 TYPE_CTRL_TMF :
1780 TYPE_CTRL_AN);
1781 vhost_scsi_log_write(vq, vq_log, log_num);
1782 }
1783 } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1784 out:
1785 mutex_unlock(&vq->mutex);
1786 }
1787
vhost_scsi_ctl_handle_kick(struct vhost_work * work)1788 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1789 {
1790 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1791 poll.work);
1792 struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1793
1794 pr_debug("%s: The handling func for control queue.\n", __func__);
1795 vhost_scsi_ctl_handle_vq(vs, vq);
1796 }
1797
1798 static void
vhost_scsi_send_evt(struct vhost_scsi * vs,struct vhost_virtqueue * vq,struct vhost_scsi_tpg * tpg,struct se_lun * lun,u32 event,u32 reason)1799 vhost_scsi_send_evt(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1800 struct vhost_scsi_tpg *tpg, struct se_lun *lun,
1801 u32 event, u32 reason)
1802 {
1803 struct vhost_scsi_evt *evt;
1804
1805 evt = vhost_scsi_allocate_evt(vs, event, reason);
1806 if (!evt)
1807 return;
1808
1809 if (tpg && lun) {
1810 /* TODO: share lun setup code with virtio-scsi.ko */
1811 /*
1812 * Note: evt->event is zeroed when we allocate it and
1813 * lun[4-7] need to be zero according to virtio-scsi spec.
1814 */
1815 evt->event.lun[0] = 0x01;
1816 evt->event.lun[1] = tpg->tport_tpgt;
1817 if (lun->unpacked_lun >= 256)
1818 evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1819 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1820 }
1821
1822 llist_add(&evt->list, &vs->vs_event_list);
1823 if (!vhost_vq_work_queue(vq, &vs->vs_event_work))
1824 vhost_scsi_complete_events(vs, true);
1825 }
1826
vhost_scsi_evt_handle_kick(struct vhost_work * work)1827 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1828 {
1829 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1830 poll.work);
1831 struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1832
1833 mutex_lock(&vq->mutex);
1834 if (!vhost_vq_get_backend(vq))
1835 goto out;
1836
1837 if (vs->vs_events_missed)
1838 vhost_scsi_send_evt(vs, vq, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT,
1839 0);
1840 out:
1841 mutex_unlock(&vq->mutex);
1842 }
1843
vhost_scsi_handle_kick(struct vhost_work * work)1844 static void vhost_scsi_handle_kick(struct vhost_work *work)
1845 {
1846 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1847 poll.work);
1848 struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1849
1850 vhost_scsi_handle_vq(vs, vq);
1851 }
1852
1853 /* Callers must hold dev mutex */
vhost_scsi_flush(struct vhost_scsi * vs)1854 static void vhost_scsi_flush(struct vhost_scsi *vs)
1855 {
1856 int i;
1857
1858 /* Init new inflight and remember the old inflight */
1859 vhost_scsi_init_inflight(vs, vs->old_inflight);
1860
1861 /*
1862 * The inflight->kref was initialized to 1. We decrement it here to
1863 * indicate the start of the flush operation so that it will reach 0
1864 * when all the reqs are finished.
1865 */
1866 for (i = 0; i < vs->dev.nvqs; i++)
1867 kref_put(&vs->old_inflight[i]->kref, vhost_scsi_done_inflight);
1868
1869 /* Flush both the vhost poll and vhost work */
1870 vhost_dev_flush(&vs->dev);
1871
1872 /* Wait for all reqs issued before the flush to be finished */
1873 for (i = 0; i < vs->dev.nvqs; i++)
1874 wait_for_completion(&vs->old_inflight[i]->comp);
1875 }
1876
vhost_scsi_destroy_vq_log(struct vhost_virtqueue * vq)1877 static void vhost_scsi_destroy_vq_log(struct vhost_virtqueue *vq)
1878 {
1879 struct vhost_scsi_virtqueue *svq = container_of(vq,
1880 struct vhost_scsi_virtqueue, vq);
1881 struct vhost_scsi_cmd *tv_cmd;
1882 unsigned int i;
1883
1884 if (!svq->scsi_cmds)
1885 return;
1886
1887 for (i = 0; i < svq->max_cmds; i++) {
1888 tv_cmd = &svq->scsi_cmds[i];
1889 kfree(tv_cmd->tvc_log);
1890 tv_cmd->tvc_log = NULL;
1891 tv_cmd->tvc_log_num = 0;
1892 }
1893 }
1894
vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue * vq)1895 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1896 {
1897 struct vhost_scsi_virtqueue *svq = container_of(vq,
1898 struct vhost_scsi_virtqueue, vq);
1899 struct vhost_scsi_cmd *tv_cmd;
1900 unsigned int i;
1901
1902 if (!svq->scsi_cmds)
1903 return;
1904
1905 for (i = 0; i < svq->max_cmds; i++) {
1906 tv_cmd = &svq->scsi_cmds[i];
1907
1908 kfree(tv_cmd->sgl);
1909 kfree(tv_cmd->prot_sgl);
1910 }
1911
1912 sbitmap_free(&svq->scsi_tags);
1913 kfree(svq->upages);
1914 vhost_scsi_destroy_vq_log(vq);
1915 kfree(svq->scsi_cmds);
1916 svq->scsi_cmds = NULL;
1917 }
1918
vhost_scsi_setup_vq_cmds(struct vhost_virtqueue * vq,int max_cmds)1919 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1920 {
1921 struct vhost_scsi_virtqueue *svq = container_of(vq,
1922 struct vhost_scsi_virtqueue, vq);
1923 struct vhost_scsi *vs = svq->vs;
1924 struct vhost_scsi_cmd *tv_cmd;
1925 unsigned int i;
1926
1927 if (svq->scsi_cmds)
1928 return 0;
1929
1930 if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1931 NUMA_NO_NODE, false, true))
1932 return -ENOMEM;
1933 svq->max_cmds = max_cmds;
1934
1935 svq->scsi_cmds = kzalloc_objs(*tv_cmd, max_cmds);
1936 if (!svq->scsi_cmds) {
1937 sbitmap_free(&svq->scsi_tags);
1938 return -ENOMEM;
1939 }
1940
1941 svq->upages = kzalloc_objs(struct page *, VHOST_SCSI_PREALLOC_UPAGES);
1942 if (!svq->upages)
1943 goto out;
1944
1945 for (i = 0; i < max_cmds; i++) {
1946 tv_cmd = &svq->scsi_cmds[i];
1947
1948 if (vs->inline_sg_cnt) {
1949 tv_cmd->sgl = kzalloc_objs(struct scatterlist,
1950 vs->inline_sg_cnt);
1951 if (!tv_cmd->sgl) {
1952 pr_err("Unable to allocate tv_cmd->sgl\n");
1953 goto out;
1954 }
1955 }
1956
1957 if (vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI) &&
1958 vs->inline_sg_cnt) {
1959 tv_cmd->prot_sgl = kzalloc_objs(struct scatterlist,
1960 vs->inline_sg_cnt);
1961 if (!tv_cmd->prot_sgl) {
1962 pr_err("Unable to allocate tv_cmd->prot_sgl\n");
1963 goto out;
1964 }
1965 }
1966 }
1967 return 0;
1968 out:
1969 vhost_scsi_destroy_vq_cmds(vq);
1970 return -ENOMEM;
1971 }
1972
1973 /*
1974 * Called from vhost_scsi_ioctl() context to walk the list of available
1975 * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1976 *
1977 * The lock nesting rule is:
1978 * vs->dev.mutex -> vhost_scsi_mutex -> tpg->tv_tpg_mutex -> vq->mutex
1979 */
1980 static int
vhost_scsi_set_endpoint(struct vhost_scsi * vs,struct vhost_scsi_target * t)1981 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1982 struct vhost_scsi_target *t)
1983 {
1984 struct se_portal_group *se_tpg;
1985 struct vhost_scsi_tport *tv_tport;
1986 struct vhost_scsi_tpg *tpg;
1987 struct vhost_scsi_tpg **vs_tpg;
1988 struct vhost_virtqueue *vq;
1989 int index, ret, i, len;
1990 bool match = false;
1991
1992 mutex_lock(&vs->dev.mutex);
1993
1994 /* Verify that ring has been setup correctly. */
1995 for (index = 0; index < vs->dev.nvqs; ++index) {
1996 /* Verify that ring has been setup correctly. */
1997 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1998 ret = -EFAULT;
1999 goto out;
2000 }
2001 }
2002
2003 if (vs->vs_tpg) {
2004 pr_err("vhost-scsi endpoint already set for %s.\n",
2005 vs->vs_vhost_wwpn);
2006 ret = -EEXIST;
2007 goto out;
2008 }
2009
2010 len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
2011 vs_tpg = kzalloc(len, GFP_KERNEL);
2012 if (!vs_tpg) {
2013 ret = -ENOMEM;
2014 goto out;
2015 }
2016
2017 mutex_lock(&vhost_scsi_mutex);
2018 list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
2019 mutex_lock(&tpg->tv_tpg_mutex);
2020 if (!tpg->tpg_nexus) {
2021 mutex_unlock(&tpg->tv_tpg_mutex);
2022 continue;
2023 }
2024 if (tpg->tv_tpg_vhost_count != 0) {
2025 mutex_unlock(&tpg->tv_tpg_mutex);
2026 continue;
2027 }
2028 tv_tport = tpg->tport;
2029
2030 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
2031 /*
2032 * In order to ensure individual vhost-scsi configfs
2033 * groups cannot be removed while in use by vhost ioctl,
2034 * go ahead and take an explicit se_tpg->tpg_group.cg_item
2035 * dependency now.
2036 */
2037 se_tpg = &tpg->se_tpg;
2038 ret = target_depend_item(&se_tpg->tpg_group.cg_item);
2039 if (ret) {
2040 pr_warn("target_depend_item() failed: %d\n", ret);
2041 mutex_unlock(&tpg->tv_tpg_mutex);
2042 mutex_unlock(&vhost_scsi_mutex);
2043 goto undepend;
2044 }
2045 tpg->tv_tpg_vhost_count++;
2046 tpg->vhost_scsi = vs;
2047 vs_tpg[tpg->tport_tpgt] = tpg;
2048 match = true;
2049 }
2050 mutex_unlock(&tpg->tv_tpg_mutex);
2051 }
2052 mutex_unlock(&vhost_scsi_mutex);
2053
2054 if (match) {
2055 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
2056 sizeof(vs->vs_vhost_wwpn));
2057
2058 for (i = VHOST_SCSI_VQ_IO; i < vs->dev.nvqs; i++) {
2059 vq = &vs->vqs[i].vq;
2060 if (!vhost_vq_is_setup(vq))
2061 continue;
2062
2063 ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
2064 if (ret)
2065 goto destroy_vq_cmds;
2066 }
2067
2068 for (i = 0; i < vs->dev.nvqs; i++) {
2069 vq = &vs->vqs[i].vq;
2070 mutex_lock(&vq->mutex);
2071 vhost_vq_set_backend(vq, vs_tpg);
2072 vhost_vq_init_access(vq);
2073 mutex_unlock(&vq->mutex);
2074 }
2075 ret = 0;
2076 } else {
2077 ret = -ENODEV;
2078 goto free_tpg;
2079 }
2080
2081 /*
2082 * Act as synchronize_rcu to make sure requests after this point
2083 * see a fully setup device.
2084 */
2085 vhost_scsi_flush(vs);
2086 vs->vs_tpg = vs_tpg;
2087 goto out;
2088
2089 destroy_vq_cmds:
2090 for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
2091 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
2092 vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
2093 }
2094 undepend:
2095 for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
2096 tpg = vs_tpg[i];
2097 if (tpg) {
2098 mutex_lock(&tpg->tv_tpg_mutex);
2099 tpg->vhost_scsi = NULL;
2100 tpg->tv_tpg_vhost_count--;
2101 mutex_unlock(&tpg->tv_tpg_mutex);
2102 target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
2103 }
2104 }
2105 free_tpg:
2106 kfree(vs_tpg);
2107 out:
2108 mutex_unlock(&vs->dev.mutex);
2109 return ret;
2110 }
2111
2112 static int
vhost_scsi_clear_endpoint(struct vhost_scsi * vs,struct vhost_scsi_target * t)2113 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
2114 struct vhost_scsi_target *t)
2115 {
2116 struct se_portal_group *se_tpg;
2117 struct vhost_scsi_tport *tv_tport;
2118 struct vhost_scsi_tpg *tpg;
2119 struct vhost_virtqueue *vq;
2120 bool match = false;
2121 int index, ret, i;
2122 u8 target;
2123
2124 mutex_lock(&vs->dev.mutex);
2125 /* Verify that ring has been setup correctly. */
2126 for (index = 0; index < vs->dev.nvqs; ++index) {
2127 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
2128 ret = -EFAULT;
2129 goto err_dev;
2130 }
2131 }
2132
2133 if (!vs->vs_tpg) {
2134 ret = 0;
2135 goto err_dev;
2136 }
2137
2138 for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
2139 target = i;
2140 tpg = vs->vs_tpg[target];
2141 if (!tpg)
2142 continue;
2143
2144 tv_tport = tpg->tport;
2145 if (!tv_tport) {
2146 ret = -ENODEV;
2147 goto err_dev;
2148 }
2149
2150 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
2151 pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
2152 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
2153 tv_tport->tport_name, tpg->tport_tpgt,
2154 t->vhost_wwpn, t->vhost_tpgt);
2155 ret = -EINVAL;
2156 goto err_dev;
2157 }
2158 match = true;
2159 }
2160 if (!match)
2161 goto free_vs_tpg;
2162
2163 /* Prevent new cmds from starting and accessing the tpgs/sessions */
2164 for (i = 0; i < vs->dev.nvqs; i++) {
2165 vq = &vs->vqs[i].vq;
2166 mutex_lock(&vq->mutex);
2167 vhost_vq_set_backend(vq, NULL);
2168 mutex_unlock(&vq->mutex);
2169 }
2170 /* Make sure cmds are not running before tearing them down. */
2171 vhost_scsi_flush(vs);
2172
2173 for (i = 0; i < vs->dev.nvqs; i++) {
2174 vq = &vs->vqs[i].vq;
2175 vhost_scsi_destroy_vq_cmds(vq);
2176 }
2177
2178 /*
2179 * We can now release our hold on the tpg and sessions and userspace
2180 * can free them after this point.
2181 */
2182 for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
2183 target = i;
2184 tpg = vs->vs_tpg[target];
2185 if (!tpg)
2186 continue;
2187
2188 mutex_lock(&tpg->tv_tpg_mutex);
2189
2190 tpg->tv_tpg_vhost_count--;
2191 tpg->vhost_scsi = NULL;
2192 vs->vs_tpg[target] = NULL;
2193
2194 mutex_unlock(&tpg->tv_tpg_mutex);
2195
2196 se_tpg = &tpg->se_tpg;
2197 target_undepend_item(&se_tpg->tpg_group.cg_item);
2198 }
2199
2200 free_vs_tpg:
2201 /*
2202 * Act as synchronize_rcu to make sure access to
2203 * old vs->vs_tpg is finished.
2204 */
2205 vhost_scsi_flush(vs);
2206 kfree(vs->vs_tpg);
2207 vs->vs_tpg = NULL;
2208 memset(vs->vs_vhost_wwpn, 0, sizeof(vs->vs_vhost_wwpn));
2209 WARN_ON(vs->vs_events_nr);
2210 mutex_unlock(&vs->dev.mutex);
2211 return 0;
2212
2213 err_dev:
2214 mutex_unlock(&vs->dev.mutex);
2215 return ret;
2216 }
2217
vhost_scsi_set_features(struct vhost_scsi * vs,u64 features)2218 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
2219 {
2220 struct vhost_virtqueue *vq;
2221 bool is_log, was_log;
2222 int i;
2223
2224 if (features & ~VHOST_SCSI_FEATURES)
2225 return -EOPNOTSUPP;
2226
2227 mutex_lock(&vs->dev.mutex);
2228 if ((features & (1 << VHOST_F_LOG_ALL)) &&
2229 !vhost_log_access_ok(&vs->dev)) {
2230 mutex_unlock(&vs->dev.mutex);
2231 return -EFAULT;
2232 }
2233
2234 if (!vs->dev.nvqs)
2235 goto out;
2236
2237 is_log = features & (1 << VHOST_F_LOG_ALL);
2238 /*
2239 * All VQs should have same feature.
2240 */
2241 was_log = vhost_has_feature(&vs->vqs[0].vq, VHOST_F_LOG_ALL);
2242
2243 for (i = 0; i < vs->dev.nvqs; i++) {
2244 vq = &vs->vqs[i].vq;
2245 mutex_lock(&vq->mutex);
2246 vq->acked_features = features;
2247 mutex_unlock(&vq->mutex);
2248 }
2249
2250 /*
2251 * If VHOST_F_LOG_ALL is removed, free tvc_log after
2252 * vq->acked_features is committed.
2253 */
2254 if (!is_log && was_log) {
2255 for (i = VHOST_SCSI_VQ_IO; i < vs->dev.nvqs; i++) {
2256 if (!vs->vqs[i].scsi_cmds)
2257 continue;
2258
2259 vq = &vs->vqs[i].vq;
2260 mutex_lock(&vq->mutex);
2261 vhost_scsi_destroy_vq_log(vq);
2262 mutex_unlock(&vq->mutex);
2263 }
2264 }
2265
2266 out:
2267 mutex_unlock(&vs->dev.mutex);
2268 return 0;
2269 }
2270
vhost_scsi_open(struct inode * inode,struct file * f)2271 static int vhost_scsi_open(struct inode *inode, struct file *f)
2272 {
2273 struct vhost_scsi_virtqueue *svq;
2274 struct vhost_scsi *vs;
2275 struct vhost_virtqueue **vqs;
2276 int r = -ENOMEM, i, nvqs = vhost_scsi_max_io_vqs;
2277
2278 vs = kvzalloc_obj(*vs);
2279 if (!vs)
2280 goto err_vs;
2281 vs->inline_sg_cnt = vhost_scsi_inline_sg_cnt;
2282
2283 if (nvqs > VHOST_SCSI_MAX_IO_VQ) {
2284 pr_err("Invalid max_io_vqs of %d. Using %d.\n", nvqs,
2285 VHOST_SCSI_MAX_IO_VQ);
2286 nvqs = VHOST_SCSI_MAX_IO_VQ;
2287 } else if (nvqs == 0) {
2288 pr_err("Invalid max_io_vqs of %d. Using 1.\n", nvqs);
2289 nvqs = 1;
2290 }
2291 nvqs += VHOST_SCSI_VQ_IO;
2292
2293 vs->old_inflight = kmalloc_objs(*vs->old_inflight, nvqs,
2294 GFP_KERNEL | __GFP_ZERO);
2295 if (!vs->old_inflight)
2296 goto err_inflight;
2297
2298 vs->vqs = kmalloc_objs(*vs->vqs, nvqs, GFP_KERNEL | __GFP_ZERO);
2299 if (!vs->vqs)
2300 goto err_vqs;
2301
2302 vqs = kmalloc_objs(*vqs, nvqs);
2303 if (!vqs)
2304 goto err_local_vqs;
2305
2306 vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
2307
2308 vs->vs_events_nr = 0;
2309 vs->vs_events_missed = false;
2310
2311 vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
2312 vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
2313 vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
2314 vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
2315 for (i = VHOST_SCSI_VQ_IO; i < nvqs; i++) {
2316 svq = &vs->vqs[i];
2317
2318 vqs[i] = &svq->vq;
2319 svq->vs = vs;
2320 init_llist_head(&svq->completion_list);
2321 vhost_work_init(&svq->completion_work,
2322 vhost_scsi_complete_cmd_work);
2323 svq->vq.handle_kick = vhost_scsi_handle_kick;
2324 }
2325 vhost_dev_init(&vs->dev, vqs, nvqs, UIO_MAXIOV,
2326 VHOST_SCSI_WEIGHT, 0, true, NULL);
2327
2328 vhost_scsi_init_inflight(vs, NULL);
2329
2330 f->private_data = vs;
2331 return 0;
2332
2333 err_local_vqs:
2334 kfree(vs->vqs);
2335 err_vqs:
2336 kfree(vs->old_inflight);
2337 err_inflight:
2338 kvfree(vs);
2339 err_vs:
2340 return r;
2341 }
2342
vhost_scsi_release(struct inode * inode,struct file * f)2343 static int vhost_scsi_release(struct inode *inode, struct file *f)
2344 {
2345 struct vhost_scsi *vs = f->private_data;
2346 struct vhost_scsi_target t;
2347
2348 mutex_lock(&vs->dev.mutex);
2349 memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
2350 mutex_unlock(&vs->dev.mutex);
2351 vhost_scsi_clear_endpoint(vs, &t);
2352 vhost_dev_stop(&vs->dev);
2353 vhost_dev_cleanup(&vs->dev);
2354 kfree(vs->dev.vqs);
2355 kfree(vs->vqs);
2356 kfree(vs->old_inflight);
2357 kvfree(vs);
2358 return 0;
2359 }
2360
2361 static long
vhost_scsi_ioctl(struct file * f,unsigned int ioctl,unsigned long arg)2362 vhost_scsi_ioctl(struct file *f,
2363 unsigned int ioctl,
2364 unsigned long arg)
2365 {
2366 struct vhost_scsi *vs = f->private_data;
2367 struct vhost_scsi_target backend;
2368 void __user *argp = (void __user *)arg;
2369 u64 __user *featurep = argp;
2370 u32 __user *eventsp = argp;
2371 u32 events_missed;
2372 u64 features;
2373 int r, abi_version = VHOST_SCSI_ABI_VERSION;
2374 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
2375
2376 switch (ioctl) {
2377 case VHOST_SCSI_SET_ENDPOINT:
2378 if (copy_from_user(&backend, argp, sizeof backend))
2379 return -EFAULT;
2380 if (backend.reserved != 0)
2381 return -EOPNOTSUPP;
2382
2383 return vhost_scsi_set_endpoint(vs, &backend);
2384 case VHOST_SCSI_CLEAR_ENDPOINT:
2385 if (copy_from_user(&backend, argp, sizeof backend))
2386 return -EFAULT;
2387 if (backend.reserved != 0)
2388 return -EOPNOTSUPP;
2389
2390 return vhost_scsi_clear_endpoint(vs, &backend);
2391 case VHOST_SCSI_GET_ABI_VERSION:
2392 if (copy_to_user(argp, &abi_version, sizeof abi_version))
2393 return -EFAULT;
2394 return 0;
2395 case VHOST_SCSI_SET_EVENTS_MISSED:
2396 if (get_user(events_missed, eventsp))
2397 return -EFAULT;
2398 mutex_lock(&vq->mutex);
2399 vs->vs_events_missed = events_missed;
2400 mutex_unlock(&vq->mutex);
2401 return 0;
2402 case VHOST_SCSI_GET_EVENTS_MISSED:
2403 mutex_lock(&vq->mutex);
2404 events_missed = vs->vs_events_missed;
2405 mutex_unlock(&vq->mutex);
2406 if (put_user(events_missed, eventsp))
2407 return -EFAULT;
2408 return 0;
2409 case VHOST_GET_FEATURES:
2410 features = VHOST_SCSI_FEATURES;
2411 if (copy_to_user(featurep, &features, sizeof features))
2412 return -EFAULT;
2413 return 0;
2414 case VHOST_SET_FEATURES:
2415 if (copy_from_user(&features, featurep, sizeof features))
2416 return -EFAULT;
2417 return vhost_scsi_set_features(vs, features);
2418 case VHOST_NEW_WORKER:
2419 case VHOST_FREE_WORKER:
2420 case VHOST_ATTACH_VRING_WORKER:
2421 case VHOST_GET_VRING_WORKER:
2422 mutex_lock(&vs->dev.mutex);
2423 r = vhost_worker_ioctl(&vs->dev, ioctl, argp);
2424 mutex_unlock(&vs->dev.mutex);
2425 return r;
2426 default:
2427 mutex_lock(&vs->dev.mutex);
2428 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
2429 /* TODO: flush backend after dev ioctl. */
2430 if (r == -ENOIOCTLCMD)
2431 r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
2432 mutex_unlock(&vs->dev.mutex);
2433 return r;
2434 }
2435 }
2436
2437 static const struct file_operations vhost_scsi_fops = {
2438 .owner = THIS_MODULE,
2439 .release = vhost_scsi_release,
2440 .unlocked_ioctl = vhost_scsi_ioctl,
2441 .compat_ioctl = compat_ptr_ioctl,
2442 .open = vhost_scsi_open,
2443 .llseek = noop_llseek,
2444 };
2445
2446 static struct miscdevice vhost_scsi_misc = {
2447 MISC_DYNAMIC_MINOR,
2448 "vhost-scsi",
2449 &vhost_scsi_fops,
2450 };
2451
vhost_scsi_register(void)2452 static int __init vhost_scsi_register(void)
2453 {
2454 return misc_register(&vhost_scsi_misc);
2455 }
2456
vhost_scsi_deregister(void)2457 static void vhost_scsi_deregister(void)
2458 {
2459 misc_deregister(&vhost_scsi_misc);
2460 }
2461
vhost_scsi_dump_proto_id(struct vhost_scsi_tport * tport)2462 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
2463 {
2464 switch (tport->tport_proto_id) {
2465 case SCSI_PROTOCOL_SAS:
2466 return "SAS";
2467 case SCSI_PROTOCOL_FCP:
2468 return "FCP";
2469 case SCSI_PROTOCOL_ISCSI:
2470 return "iSCSI";
2471 default:
2472 break;
2473 }
2474
2475 return "Unknown";
2476 }
2477
2478 static void
vhost_scsi_do_plug(struct vhost_scsi_tpg * tpg,struct se_lun * lun,bool plug)2479 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
2480 struct se_lun *lun, bool plug)
2481 {
2482
2483 struct vhost_scsi *vs = tpg->vhost_scsi;
2484 struct vhost_virtqueue *vq;
2485 u32 reason;
2486
2487 if (!vs)
2488 return;
2489
2490 if (plug)
2491 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
2492 else
2493 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
2494
2495 vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
2496 mutex_lock(&vq->mutex);
2497 /*
2498 * We can't queue events if the backend has been cleared, because
2499 * we could end up queueing an event after the flush.
2500 */
2501 if (!vhost_vq_get_backend(vq))
2502 goto unlock;
2503
2504 if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
2505 vhost_scsi_send_evt(vs, vq, tpg, lun,
2506 VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
2507 unlock:
2508 mutex_unlock(&vq->mutex);
2509 }
2510
vhost_scsi_hotplug(struct vhost_scsi_tpg * tpg,struct se_lun * lun)2511 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2512 {
2513 vhost_scsi_do_plug(tpg, lun, true);
2514 }
2515
vhost_scsi_hotunplug(struct vhost_scsi_tpg * tpg,struct se_lun * lun)2516 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2517 {
2518 vhost_scsi_do_plug(tpg, lun, false);
2519 }
2520
vhost_scsi_port_link(struct se_portal_group * se_tpg,struct se_lun * lun)2521 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
2522 struct se_lun *lun)
2523 {
2524 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2525 struct vhost_scsi_tpg, se_tpg);
2526
2527 mutex_lock(&tpg->tv_tpg_mutex);
2528 tpg->tv_tpg_port_count++;
2529 vhost_scsi_hotplug(tpg, lun);
2530 mutex_unlock(&tpg->tv_tpg_mutex);
2531
2532 return 0;
2533 }
2534
vhost_scsi_port_unlink(struct se_portal_group * se_tpg,struct se_lun * lun)2535 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2536 struct se_lun *lun)
2537 {
2538 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2539 struct vhost_scsi_tpg, se_tpg);
2540
2541 mutex_lock(&tpg->tv_tpg_mutex);
2542 tpg->tv_tpg_port_count--;
2543 vhost_scsi_hotunplug(tpg, lun);
2544 mutex_unlock(&tpg->tv_tpg_mutex);
2545 }
2546
vhost_scsi_tpg_attrib_fabric_prot_type_store(struct config_item * item,const char * page,size_t count)2547 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2548 struct config_item *item, const char *page, size_t count)
2549 {
2550 struct se_portal_group *se_tpg = attrib_to_tpg(item);
2551 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2552 struct vhost_scsi_tpg, se_tpg);
2553 unsigned long val;
2554 int ret = kstrtoul(page, 0, &val);
2555
2556 if (ret) {
2557 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2558 return ret;
2559 }
2560 if (val != 0 && val != 1 && val != 3) {
2561 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2562 return -EINVAL;
2563 }
2564 tpg->tv_fabric_prot_type = val;
2565
2566 return count;
2567 }
2568
vhost_scsi_tpg_attrib_fabric_prot_type_show(struct config_item * item,char * page)2569 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2570 struct config_item *item, char *page)
2571 {
2572 struct se_portal_group *se_tpg = attrib_to_tpg(item);
2573 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2574 struct vhost_scsi_tpg, se_tpg);
2575
2576 return sysfs_emit(page, "%d\n", tpg->tv_fabric_prot_type);
2577 }
2578
2579 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2580
2581 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2582 &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2583 NULL,
2584 };
2585
vhost_scsi_make_nexus(struct vhost_scsi_tpg * tpg,const char * name)2586 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2587 const char *name)
2588 {
2589 struct vhost_scsi_nexus *tv_nexus;
2590
2591 mutex_lock(&tpg->tv_tpg_mutex);
2592 if (tpg->tpg_nexus) {
2593 mutex_unlock(&tpg->tv_tpg_mutex);
2594 pr_debug("tpg->tpg_nexus already exists\n");
2595 return -EEXIST;
2596 }
2597
2598 tv_nexus = kzalloc_obj(*tv_nexus);
2599 if (!tv_nexus) {
2600 mutex_unlock(&tpg->tv_tpg_mutex);
2601 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2602 return -ENOMEM;
2603 }
2604 /*
2605 * Since we are running in 'demo mode' this call will generate a
2606 * struct se_node_acl for the vhost_scsi struct se_portal_group with
2607 * the SCSI Initiator port name of the passed configfs group 'name'.
2608 */
2609 tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2610 TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2611 (unsigned char *)name, tv_nexus, NULL);
2612 if (IS_ERR(tv_nexus->tvn_se_sess)) {
2613 mutex_unlock(&tpg->tv_tpg_mutex);
2614 kfree(tv_nexus);
2615 return -ENOMEM;
2616 }
2617 tpg->tpg_nexus = tv_nexus;
2618
2619 mutex_unlock(&tpg->tv_tpg_mutex);
2620 return 0;
2621 }
2622
vhost_scsi_drop_nexus(struct vhost_scsi_tpg * tpg)2623 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2624 {
2625 struct se_session *se_sess;
2626 struct vhost_scsi_nexus *tv_nexus;
2627
2628 mutex_lock(&tpg->tv_tpg_mutex);
2629 tv_nexus = tpg->tpg_nexus;
2630 if (!tv_nexus) {
2631 mutex_unlock(&tpg->tv_tpg_mutex);
2632 return -ENODEV;
2633 }
2634
2635 se_sess = tv_nexus->tvn_se_sess;
2636 if (!se_sess) {
2637 mutex_unlock(&tpg->tv_tpg_mutex);
2638 return -ENODEV;
2639 }
2640
2641 if (tpg->tv_tpg_port_count != 0) {
2642 mutex_unlock(&tpg->tv_tpg_mutex);
2643 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2644 " active TPG port count: %d\n",
2645 tpg->tv_tpg_port_count);
2646 return -EBUSY;
2647 }
2648
2649 if (tpg->tv_tpg_vhost_count != 0) {
2650 mutex_unlock(&tpg->tv_tpg_mutex);
2651 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2652 " active TPG vhost count: %d\n",
2653 tpg->tv_tpg_vhost_count);
2654 return -EBUSY;
2655 }
2656
2657 pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2658 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2659 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2660
2661 /*
2662 * Release the SCSI I_T Nexus to the emulated vhost Target Port
2663 */
2664 target_remove_session(se_sess);
2665 tpg->tpg_nexus = NULL;
2666 mutex_unlock(&tpg->tv_tpg_mutex);
2667
2668 kfree(tv_nexus);
2669 return 0;
2670 }
2671
vhost_scsi_tpg_nexus_show(struct config_item * item,char * page)2672 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2673 {
2674 struct se_portal_group *se_tpg = to_tpg(item);
2675 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2676 struct vhost_scsi_tpg, se_tpg);
2677 struct vhost_scsi_nexus *tv_nexus;
2678 ssize_t ret;
2679
2680 mutex_lock(&tpg->tv_tpg_mutex);
2681 tv_nexus = tpg->tpg_nexus;
2682 if (!tv_nexus) {
2683 mutex_unlock(&tpg->tv_tpg_mutex);
2684 return -ENODEV;
2685 }
2686 ret = sysfs_emit(page, "%s\n",
2687 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2688 mutex_unlock(&tpg->tv_tpg_mutex);
2689
2690 return ret;
2691 }
2692
vhost_scsi_tpg_nexus_store(struct config_item * item,const char * page,size_t count)2693 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2694 const char *page, size_t count)
2695 {
2696 struct se_portal_group *se_tpg = to_tpg(item);
2697 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2698 struct vhost_scsi_tpg, se_tpg);
2699 struct vhost_scsi_tport *tport_wwn = tpg->tport;
2700 unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2701 int ret;
2702 /*
2703 * Shutdown the active I_T nexus if 'NULL' is passed..
2704 */
2705 if (!strncmp(page, "NULL", 4)) {
2706 ret = vhost_scsi_drop_nexus(tpg);
2707 return (!ret) ? count : ret;
2708 }
2709 /*
2710 * Otherwise make sure the passed virtual Initiator port WWN matches
2711 * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2712 * vhost_scsi_make_nexus().
2713 */
2714 if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2715 pr_err("Emulated NAA Sas Address: %s, exceeds"
2716 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2717 return -EINVAL;
2718 }
2719 snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2720
2721 ptr = strstr(i_port, "naa.");
2722 if (ptr) {
2723 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2724 pr_err("Passed SAS Initiator Port %s does not"
2725 " match target port protoid: %s\n", i_port,
2726 vhost_scsi_dump_proto_id(tport_wwn));
2727 return -EINVAL;
2728 }
2729 port_ptr = &i_port[0];
2730 goto check_newline;
2731 }
2732 ptr = strstr(i_port, "fc.");
2733 if (ptr) {
2734 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2735 pr_err("Passed FCP Initiator Port %s does not"
2736 " match target port protoid: %s\n", i_port,
2737 vhost_scsi_dump_proto_id(tport_wwn));
2738 return -EINVAL;
2739 }
2740 port_ptr = &i_port[3]; /* Skip over "fc." */
2741 goto check_newline;
2742 }
2743 ptr = strstr(i_port, "iqn.");
2744 if (ptr) {
2745 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2746 pr_err("Passed iSCSI Initiator Port %s does not"
2747 " match target port protoid: %s\n", i_port,
2748 vhost_scsi_dump_proto_id(tport_wwn));
2749 return -EINVAL;
2750 }
2751 port_ptr = &i_port[0];
2752 goto check_newline;
2753 }
2754 pr_err("Unable to locate prefix for emulated Initiator Port:"
2755 " %s\n", i_port);
2756 return -EINVAL;
2757 /*
2758 * Clear any trailing newline for the NAA WWN
2759 */
2760 check_newline:
2761 if (i_port[strlen(i_port)-1] == '\n')
2762 i_port[strlen(i_port)-1] = '\0';
2763
2764 ret = vhost_scsi_make_nexus(tpg, port_ptr);
2765 if (ret < 0)
2766 return ret;
2767
2768 return count;
2769 }
2770
2771 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2772
2773 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2774 &vhost_scsi_tpg_attr_nexus,
2775 NULL,
2776 };
2777
2778 static struct se_portal_group *
vhost_scsi_make_tpg(struct se_wwn * wwn,const char * name)2779 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2780 {
2781 struct vhost_scsi_tport *tport = container_of(wwn,
2782 struct vhost_scsi_tport, tport_wwn);
2783
2784 struct vhost_scsi_tpg *tpg;
2785 u16 tpgt;
2786 int ret;
2787
2788 if (strstr(name, "tpgt_") != name)
2789 return ERR_PTR(-EINVAL);
2790 if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2791 return ERR_PTR(-EINVAL);
2792
2793 tpg = kzalloc_obj(*tpg);
2794 if (!tpg) {
2795 pr_err("Unable to allocate struct vhost_scsi_tpg");
2796 return ERR_PTR(-ENOMEM);
2797 }
2798 mutex_init(&tpg->tv_tpg_mutex);
2799 INIT_LIST_HEAD(&tpg->tv_tpg_list);
2800 tpg->tport = tport;
2801 tpg->tport_tpgt = tpgt;
2802
2803 ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2804 if (ret < 0) {
2805 kfree(tpg);
2806 return NULL;
2807 }
2808 mutex_lock(&vhost_scsi_mutex);
2809 list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2810 mutex_unlock(&vhost_scsi_mutex);
2811
2812 return &tpg->se_tpg;
2813 }
2814
vhost_scsi_drop_tpg(struct se_portal_group * se_tpg)2815 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2816 {
2817 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2818 struct vhost_scsi_tpg, se_tpg);
2819
2820 mutex_lock(&vhost_scsi_mutex);
2821 list_del(&tpg->tv_tpg_list);
2822 mutex_unlock(&vhost_scsi_mutex);
2823 /*
2824 * Release the virtual I_T Nexus for this vhost TPG
2825 */
2826 vhost_scsi_drop_nexus(tpg);
2827 /*
2828 * Deregister the se_tpg from TCM..
2829 */
2830 core_tpg_deregister(se_tpg);
2831 kfree(tpg);
2832 }
2833
2834 static struct se_wwn *
vhost_scsi_make_tport(struct target_fabric_configfs * tf,struct config_group * group,const char * name)2835 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2836 struct config_group *group,
2837 const char *name)
2838 {
2839 struct vhost_scsi_tport *tport;
2840 char *ptr;
2841 u64 wwpn = 0;
2842 int off = 0;
2843
2844 /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2845 return ERR_PTR(-EINVAL); */
2846
2847 tport = kzalloc_obj(*tport);
2848 if (!tport) {
2849 pr_err("Unable to allocate struct vhost_scsi_tport");
2850 return ERR_PTR(-ENOMEM);
2851 }
2852 tport->tport_wwpn = wwpn;
2853 /*
2854 * Determine the emulated Protocol Identifier and Target Port Name
2855 * based on the incoming configfs directory name.
2856 */
2857 ptr = strstr(name, "naa.");
2858 if (ptr) {
2859 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2860 goto check_len;
2861 }
2862 ptr = strstr(name, "fc.");
2863 if (ptr) {
2864 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2865 off = 3; /* Skip over "fc." */
2866 goto check_len;
2867 }
2868 ptr = strstr(name, "iqn.");
2869 if (ptr) {
2870 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2871 goto check_len;
2872 }
2873
2874 pr_err("Unable to locate prefix for emulated Target Port:"
2875 " %s\n", name);
2876 kfree(tport);
2877 return ERR_PTR(-EINVAL);
2878
2879 check_len:
2880 if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2881 pr_err("Emulated %s Address: %s, exceeds"
2882 " max: %d\n", vhost_scsi_dump_proto_id(tport), name,
2883 VHOST_SCSI_NAMELEN);
2884 kfree(tport);
2885 return ERR_PTR(-EINVAL);
2886 }
2887 snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2888
2889 pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2890 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2891
2892 return &tport->tport_wwn;
2893 }
2894
vhost_scsi_drop_tport(struct se_wwn * wwn)2895 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2896 {
2897 struct vhost_scsi_tport *tport = container_of(wwn,
2898 struct vhost_scsi_tport, tport_wwn);
2899
2900 pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2901 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2902 tport->tport_name);
2903
2904 kfree(tport);
2905 }
2906
2907 static ssize_t
vhost_scsi_wwn_version_show(struct config_item * item,char * page)2908 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2909 {
2910 return sysfs_emit(page, "TCM_VHOST fabric module %s on %s/%s"
2911 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2912 utsname()->machine);
2913 }
2914
2915 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2916
2917 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2918 &vhost_scsi_wwn_attr_version,
2919 NULL,
2920 };
2921
2922 static const struct target_core_fabric_ops vhost_scsi_ops = {
2923 .module = THIS_MODULE,
2924 .fabric_name = "vhost",
2925 .max_data_sg_nents = VHOST_SCSI_PREALLOC_SGLS,
2926 .tpg_get_wwn = vhost_scsi_get_fabric_wwn,
2927 .tpg_get_tag = vhost_scsi_get_tpgt,
2928 .tpg_check_demo_mode = vhost_scsi_check_true,
2929 .tpg_check_demo_mode_cache = vhost_scsi_check_true,
2930 .tpg_check_prot_fabric_only = vhost_scsi_check_prot_fabric_only,
2931 .release_cmd = vhost_scsi_release_cmd,
2932 .check_stop_free = vhost_scsi_check_stop_free,
2933 .sess_get_initiator_sid = NULL,
2934 .write_pending = vhost_scsi_write_pending,
2935 .queue_data_in = vhost_scsi_queue_data_in,
2936 .queue_status = vhost_scsi_queue_status,
2937 .queue_tm_rsp = vhost_scsi_queue_tm_rsp,
2938 .aborted_task = vhost_scsi_aborted_task,
2939 /*
2940 * Setup callers for generic logic in target_core_fabric_configfs.c
2941 */
2942 .fabric_make_wwn = vhost_scsi_make_tport,
2943 .fabric_drop_wwn = vhost_scsi_drop_tport,
2944 .fabric_make_tpg = vhost_scsi_make_tpg,
2945 .fabric_drop_tpg = vhost_scsi_drop_tpg,
2946 .fabric_post_link = vhost_scsi_port_link,
2947 .fabric_pre_unlink = vhost_scsi_port_unlink,
2948
2949 .tfc_wwn_attrs = vhost_scsi_wwn_attrs,
2950 .tfc_tpg_base_attrs = vhost_scsi_tpg_attrs,
2951 .tfc_tpg_attrib_attrs = vhost_scsi_tpg_attrib_attrs,
2952
2953 .default_submit_type = TARGET_QUEUE_SUBMIT,
2954 .direct_submit_supp = 1,
2955 };
2956
vhost_scsi_init(void)2957 static int __init vhost_scsi_init(void)
2958 {
2959 int ret = -ENOMEM;
2960
2961 pr_debug("TCM_VHOST fabric module %s on %s/%s"
2962 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2963 utsname()->machine);
2964
2965 ret = vhost_scsi_register();
2966 if (ret < 0)
2967 goto out;
2968
2969 ret = target_register_template(&vhost_scsi_ops);
2970 if (ret < 0)
2971 goto out_vhost_scsi_deregister;
2972
2973 return 0;
2974
2975 out_vhost_scsi_deregister:
2976 vhost_scsi_deregister();
2977 out:
2978 return ret;
2979 }
2980
vhost_scsi_exit(void)2981 static void vhost_scsi_exit(void)
2982 {
2983 target_unregister_template(&vhost_scsi_ops);
2984 vhost_scsi_deregister();
2985 }
2986
2987 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2988 MODULE_ALIAS("tcm_vhost");
2989 MODULE_LICENSE("GPL");
2990 module_init(vhost_scsi_init);
2991 module_exit(vhost_scsi_exit);
2992