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