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