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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#include <linux/percpu_ida.h>
50
51#include "vhost.h"
52
53#define VHOST_SCSI_VERSION "v0.1"
54#define VHOST_SCSI_NAMELEN 256
55#define VHOST_SCSI_MAX_CDB_SIZE 32
56#define VHOST_SCSI_DEFAULT_TAGS 256
57#define VHOST_SCSI_PREALLOC_SGLS 2048
58#define VHOST_SCSI_PREALLOC_UPAGES 2048
59#define VHOST_SCSI_PREALLOC_PROT_SGLS 512
60
61struct vhost_scsi_inflight {
62 /* Wait for the flush operation to finish */
63 struct completion comp;
64 /* Refcount for the inflight reqs */
65 struct kref kref;
66};
67
68struct vhost_scsi_cmd {
69 /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
70 int tvc_vq_desc;
71 /* virtio-scsi initiator task attribute */
72 int tvc_task_attr;
73 /* virtio-scsi response incoming iovecs */
74 int tvc_in_iovs;
75 /* virtio-scsi initiator data direction */
76 enum dma_data_direction tvc_data_direction;
77 /* Expected data transfer length from virtio-scsi header */
78 u32 tvc_exp_data_len;
79 /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
80 u64 tvc_tag;
81 /* The number of scatterlists associated with this cmd */
82 u32 tvc_sgl_count;
83 u32 tvc_prot_sgl_count;
84 /* Saved unpacked SCSI LUN for vhost_scsi_submission_work() */
85 u32 tvc_lun;
86 /* Pointer to the SGL formatted memory from virtio-scsi */
87 struct scatterlist *tvc_sgl;
88 struct scatterlist *tvc_prot_sgl;
89 struct page **tvc_upages;
90 /* Pointer to response header iovec */
91 struct iovec tvc_resp_iov;
92 /* Pointer to vhost_scsi for our device */
93 struct vhost_scsi *tvc_vhost;
94 /* Pointer to vhost_virtqueue for the cmd */
95 struct vhost_virtqueue *tvc_vq;
96 /* Pointer to vhost nexus memory */
97 struct vhost_scsi_nexus *tvc_nexus;
98 /* The TCM I/O descriptor that is accessed via container_of() */
99 struct se_cmd tvc_se_cmd;
100 /* work item used for cmwq dispatch to vhost_scsi_submission_work() */
101 struct work_struct work;
102 /* Copy of the incoming SCSI command descriptor block (CDB) */
103 unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
104 /* Sense buffer that will be mapped into outgoing status */
105 unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
106 /* Completed commands list, serviced from vhost worker thread */
107 struct llist_node tvc_completion_list;
108 /* Used to track inflight cmd */
109 struct vhost_scsi_inflight *inflight;
110};
111
112struct vhost_scsi_nexus {
113 /* Pointer to TCM session for I_T Nexus */
114 struct se_session *tvn_se_sess;
115};
116
117struct vhost_scsi_tpg {
118 /* Vhost port target portal group tag for TCM */
119 u16 tport_tpgt;
120 /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
121 int tv_tpg_port_count;
122 /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
123 int tv_tpg_vhost_count;
124 /* Used for enabling T10-PI with legacy devices */
125 int tv_fabric_prot_type;
126 /* list for vhost_scsi_list */
127 struct list_head tv_tpg_list;
128 /* Used to protect access for tpg_nexus */
129 struct mutex tv_tpg_mutex;
130 /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
131 struct vhost_scsi_nexus *tpg_nexus;
132 /* Pointer back to vhost_scsi_tport */
133 struct vhost_scsi_tport *tport;
134 /* Returned by vhost_scsi_make_tpg() */
135 struct se_portal_group se_tpg;
136 /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
137 struct vhost_scsi *vhost_scsi;
138};
139
140struct vhost_scsi_tport {
141 /* SCSI protocol the tport is providing */
142 u8 tport_proto_id;
143 /* Binary World Wide unique Port Name for Vhost Target port */
144 u64 tport_wwpn;
145 /* ASCII formatted WWPN for Vhost Target port */
146 char tport_name[VHOST_SCSI_NAMELEN];
147 /* Returned by vhost_scsi_make_tport() */
148 struct se_wwn tport_wwn;
149};
150
151struct vhost_scsi_evt {
152 /* event to be sent to guest */
153 struct virtio_scsi_event event;
154 /* event list, serviced from vhost worker thread */
155 struct llist_node list;
156};
157
158enum {
159 VHOST_SCSI_VQ_CTL = 0,
160 VHOST_SCSI_VQ_EVT = 1,
161 VHOST_SCSI_VQ_IO = 2,
162};
163
164/* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
165enum {
166 VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
167 (1ULL << VIRTIO_SCSI_F_T10_PI)
168};
169
170#define VHOST_SCSI_MAX_TARGET 256
171#define VHOST_SCSI_MAX_VQ 128
172#define VHOST_SCSI_MAX_EVENT 128
173
174struct vhost_scsi_virtqueue {
175 struct vhost_virtqueue vq;
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};
188
189struct vhost_scsi {
190 /* Protected by vhost_scsi->dev.mutex */
191 struct vhost_scsi_tpg **vs_tpg;
192 char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
193
194 struct vhost_dev dev;
195 struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
196
197 struct vhost_work vs_completion_work; /* cmd completion work item */
198 struct llist_head vs_completion_list; /* cmd completion queue */
199
200 struct vhost_work vs_event_work; /* evt injection work item */
201 struct llist_head vs_event_list; /* evt injection queue */
202
203 bool vs_events_missed; /* any missed events, protected by vq->mutex */
204 int vs_events_nr; /* num of pending events, protected by vq->mutex */
205};
206
207static struct workqueue_struct *vhost_scsi_workqueue;
208
209/* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
210static DEFINE_MUTEX(vhost_scsi_mutex);
211static LIST_HEAD(vhost_scsi_list);
212
213static void vhost_scsi_done_inflight(struct kref *kref)
214{
215 struct vhost_scsi_inflight *inflight;
216
217 inflight = container_of(kref, struct vhost_scsi_inflight, kref);
218 complete(&inflight->comp);
219}
220
221static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
222 struct vhost_scsi_inflight *old_inflight[])
223{
224 struct vhost_scsi_inflight *new_inflight;
225 struct vhost_virtqueue *vq;
226 int idx, i;
227
228 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
229 vq = &vs->vqs[i].vq;
230
231 mutex_lock(&vq->mutex);
232
233 /* store old infight */
234 idx = vs->vqs[i].inflight_idx;
235 if (old_inflight)
236 old_inflight[i] = &vs->vqs[i].inflights[idx];
237
238 /* setup new infight */
239 vs->vqs[i].inflight_idx = idx ^ 1;
240 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
241 kref_init(&new_inflight->kref);
242 init_completion(&new_inflight->comp);
243
244 mutex_unlock(&vq->mutex);
245 }
246}
247
248static struct vhost_scsi_inflight *
249vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
250{
251 struct vhost_scsi_inflight *inflight;
252 struct vhost_scsi_virtqueue *svq;
253
254 svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
255 inflight = &svq->inflights[svq->inflight_idx];
256 kref_get(&inflight->kref);
257
258 return inflight;
259}
260
261static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
262{
263 kref_put(&inflight->kref, vhost_scsi_done_inflight);
264}
265
266static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
267{
268 return 1;
269}
270
271static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
272{
273 return 0;
274}
275
276static char *vhost_scsi_get_fabric_name(void)
277{
278 return "vhost";
279}
280
281static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
282{
283 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
284 struct vhost_scsi_tpg, se_tpg);
285 struct vhost_scsi_tport *tport = tpg->tport;
286
287 return &tport->tport_name[0];
288}
289
290static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
291{
292 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
293 struct vhost_scsi_tpg, se_tpg);
294 return tpg->tport_tpgt;
295}
296
297static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
298{
299 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
300 struct vhost_scsi_tpg, se_tpg);
301
302 return tpg->tv_fabric_prot_type;
303}
304
305static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
306{
307 return 1;
308}
309
310static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
311{
312 struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
313 struct vhost_scsi_cmd, tvc_se_cmd);
314 struct se_session *se_sess = tv_cmd->tvc_nexus->tvn_se_sess;
315 int i;
316
317 if (tv_cmd->tvc_sgl_count) {
318 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
319 put_page(sg_page(&tv_cmd->tvc_sgl[i]));
320 }
321 if (tv_cmd->tvc_prot_sgl_count) {
322 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
323 put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
324 }
325
326 vhost_scsi_put_inflight(tv_cmd->inflight);
327 percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
328}
329
330static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
331{
332 return 0;
333}
334
335static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
336{
337 /* Go ahead and process the write immediately */
338 target_execute_cmd(se_cmd);
339 return 0;
340}
341
342static int vhost_scsi_write_pending_status(struct se_cmd *se_cmd)
343{
344 return 0;
345}
346
347static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
348{
349 return;
350}
351
352static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
353{
354 return 0;
355}
356
357static void vhost_scsi_complete_cmd(struct vhost_scsi_cmd *cmd)
358{
359 struct vhost_scsi *vs = cmd->tvc_vhost;
360
361 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
362
363 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
364}
365
366static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
367{
368 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
369 struct vhost_scsi_cmd, tvc_se_cmd);
370 vhost_scsi_complete_cmd(cmd);
371 return 0;
372}
373
374static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
375{
376 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
377 struct vhost_scsi_cmd, tvc_se_cmd);
378 vhost_scsi_complete_cmd(cmd);
379 return 0;
380}
381
382static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
383{
384 return;
385}
386
387static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
388{
389 return;
390}
391
392static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
393{
394 vs->vs_events_nr--;
395 kfree(evt);
396}
397
398static struct vhost_scsi_evt *
399vhost_scsi_allocate_evt(struct vhost_scsi *vs,
400 u32 event, u32 reason)
401{
402 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
403 struct vhost_scsi_evt *evt;
404
405 if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
406 vs->vs_events_missed = true;
407 return NULL;
408 }
409
410 evt = kzalloc(sizeof(*evt), GFP_KERNEL);
411 if (!evt) {
412 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
413 vs->vs_events_missed = true;
414 return NULL;
415 }
416
417 evt->event.event = cpu_to_vhost32(vq, event);
418 evt->event.reason = cpu_to_vhost32(vq, reason);
419 vs->vs_events_nr++;
420
421 return evt;
422}
423
424static void vhost_scsi_free_cmd(struct vhost_scsi_cmd *cmd)
425{
426 struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
427
428 /* TODO locking against target/backend threads? */
429 transport_generic_free_cmd(se_cmd, 0);
430
431}
432
433static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
434{
435 return target_put_sess_cmd(se_cmd);
436}
437
438static void
439vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
440{
441 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
442 struct virtio_scsi_event *event = &evt->event;
443 struct virtio_scsi_event __user *eventp;
444 unsigned out, in;
445 int head, ret;
446
447 if (!vq->private_data) {
448 vs->vs_events_missed = true;
449 return;
450 }
451
452again:
453 vhost_disable_notify(&vs->dev, vq);
454 head = vhost_get_vq_desc(vq, vq->iov,
455 ARRAY_SIZE(vq->iov), &out, &in,
456 NULL, NULL);
457 if (head < 0) {
458 vs->vs_events_missed = true;
459 return;
460 }
461 if (head == vq->num) {
462 if (vhost_enable_notify(&vs->dev, vq))
463 goto again;
464 vs->vs_events_missed = true;
465 return;
466 }
467
468 if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
469 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
470 vq->iov[out].iov_len);
471 vs->vs_events_missed = true;
472 return;
473 }
474
475 if (vs->vs_events_missed) {
476 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
477 vs->vs_events_missed = false;
478 }
479
480 eventp = vq->iov[out].iov_base;
481 ret = __copy_to_user(eventp, event, sizeof(*event));
482 if (!ret)
483 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
484 else
485 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
486}
487
488static void vhost_scsi_evt_work(struct vhost_work *work)
489{
490 struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
491 vs_event_work);
492 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
493 struct vhost_scsi_evt *evt, *t;
494 struct llist_node *llnode;
495
496 mutex_lock(&vq->mutex);
497 llnode = llist_del_all(&vs->vs_event_list);
498 llist_for_each_entry_safe(evt, t, llnode, list) {
499 vhost_scsi_do_evt_work(vs, evt);
500 vhost_scsi_free_evt(vs, evt);
501 }
502 mutex_unlock(&vq->mutex);
503}
504
505/* Fill in status and signal that we are done processing this command
506 *
507 * This is scheduled in the vhost work queue so we are called with the owner
508 * process mm and can access the vring.
509 */
510static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
511{
512 struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
513 vs_completion_work);
514 DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
515 struct virtio_scsi_cmd_resp v_rsp;
516 struct vhost_scsi_cmd *cmd, *t;
517 struct llist_node *llnode;
518 struct se_cmd *se_cmd;
519 struct iov_iter iov_iter;
520 int ret, vq;
521
522 bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
523 llnode = llist_del_all(&vs->vs_completion_list);
524 llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
525 se_cmd = &cmd->tvc_se_cmd;
526
527 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
528 cmd, se_cmd->residual_count, se_cmd->scsi_status);
529
530 memset(&v_rsp, 0, sizeof(v_rsp));
531 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
532 /* TODO is status_qualifier field needed? */
533 v_rsp.status = se_cmd->scsi_status;
534 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
535 se_cmd->scsi_sense_length);
536 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
537 se_cmd->scsi_sense_length);
538
539 iov_iter_init(&iov_iter, READ, &cmd->tvc_resp_iov,
540 cmd->tvc_in_iovs, sizeof(v_rsp));
541 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
542 if (likely(ret == sizeof(v_rsp))) {
543 struct vhost_scsi_virtqueue *q;
544 vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
545 q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
546 vq = q - vs->vqs;
547 __set_bit(vq, signal);
548 } else
549 pr_err("Faulted on virtio_scsi_cmd_resp\n");
550
551 vhost_scsi_free_cmd(cmd);
552 }
553
554 vq = -1;
555 while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
556 < VHOST_SCSI_MAX_VQ)
557 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
558}
559
560static struct vhost_scsi_cmd *
561vhost_scsi_get_tag(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
562 unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
563 u32 exp_data_len, int data_direction)
564{
565 struct vhost_scsi_cmd *cmd;
566 struct vhost_scsi_nexus *tv_nexus;
567 struct se_session *se_sess;
568 struct scatterlist *sg, *prot_sg;
569 struct page **pages;
570 int tag;
571
572 tv_nexus = tpg->tpg_nexus;
573 if (!tv_nexus) {
574 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
575 return ERR_PTR(-EIO);
576 }
577 se_sess = tv_nexus->tvn_se_sess;
578
579 tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING);
580 if (tag < 0) {
581 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
582 return ERR_PTR(-ENOMEM);
583 }
584
585 cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[tag];
586 sg = cmd->tvc_sgl;
587 prot_sg = cmd->tvc_prot_sgl;
588 pages = cmd->tvc_upages;
589 memset(cmd, 0, sizeof(*cmd));
590 cmd->tvc_sgl = sg;
591 cmd->tvc_prot_sgl = prot_sg;
592 cmd->tvc_upages = pages;
593 cmd->tvc_se_cmd.map_tag = tag;
594 cmd->tvc_tag = scsi_tag;
595 cmd->tvc_lun = lun;
596 cmd->tvc_task_attr = task_attr;
597 cmd->tvc_exp_data_len = exp_data_len;
598 cmd->tvc_data_direction = data_direction;
599 cmd->tvc_nexus = tv_nexus;
600 cmd->inflight = vhost_scsi_get_inflight(vq);
601
602 memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
603
604 return cmd;
605}
606
607/*
608 * Map a user memory range into a scatterlist
609 *
610 * Returns the number of scatterlist entries used or -errno on error.
611 */
612static int
613vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
614 struct iov_iter *iter,
615 struct scatterlist *sgl,
616 bool write)
617{
618 struct page **pages = cmd->tvc_upages;
619 struct scatterlist *sg = sgl;
620 ssize_t bytes;
621 size_t offset;
622 unsigned int npages = 0;
623
624 bytes = iov_iter_get_pages(iter, pages, LONG_MAX,
625 VHOST_SCSI_PREALLOC_UPAGES, &offset);
626 /* No pages were pinned */
627 if (bytes <= 0)
628 return bytes < 0 ? bytes : -EFAULT;
629
630 iov_iter_advance(iter, bytes);
631
632 while (bytes) {
633 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
634 sg_set_page(sg++, pages[npages++], n, offset);
635 bytes -= n;
636 offset = 0;
637 }
638 return npages;
639}
640
641static int
642vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
643{
644 int sgl_count = 0;
645
646 if (!iter || !iter->iov) {
647 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
648 " present\n", __func__, bytes);
649 return -EINVAL;
650 }
651
652 sgl_count = iov_iter_npages(iter, 0xffff);
653 if (sgl_count > max_sgls) {
654 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
655 " max_sgls: %d\n", __func__, sgl_count, max_sgls);
656 return -EINVAL;
657 }
658 return sgl_count;
659}
660
661static int
662vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
663 struct iov_iter *iter,
664 struct scatterlist *sg, int sg_count)
665{
666 struct scatterlist *p = sg;
667 int ret;
668
669 while (iov_iter_count(iter)) {
670 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
671 if (ret < 0) {
672 while (p < sg) {
673 struct page *page = sg_page(p++);
674 if (page)
675 put_page(page);
676 }
677 return ret;
678 }
679 sg += ret;
680 }
681 return 0;
682}
683
684static int
685vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
686 size_t prot_bytes, struct iov_iter *prot_iter,
687 size_t data_bytes, struct iov_iter *data_iter)
688{
689 int sgl_count, ret;
690 bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
691
692 if (prot_bytes) {
693 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
694 VHOST_SCSI_PREALLOC_PROT_SGLS);
695 if (sgl_count < 0)
696 return sgl_count;
697
698 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
699 cmd->tvc_prot_sgl_count = sgl_count;
700 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
701 cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
702
703 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
704 cmd->tvc_prot_sgl,
705 cmd->tvc_prot_sgl_count);
706 if (ret < 0) {
707 cmd->tvc_prot_sgl_count = 0;
708 return ret;
709 }
710 }
711 sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
712 VHOST_SCSI_PREALLOC_SGLS);
713 if (sgl_count < 0)
714 return sgl_count;
715
716 sg_init_table(cmd->tvc_sgl, sgl_count);
717 cmd->tvc_sgl_count = sgl_count;
718 pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
719 cmd->tvc_sgl, cmd->tvc_sgl_count);
720
721 ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
722 cmd->tvc_sgl, cmd->tvc_sgl_count);
723 if (ret < 0) {
724 cmd->tvc_sgl_count = 0;
725 return ret;
726 }
727 return 0;
728}
729
730static int vhost_scsi_to_tcm_attr(int attr)
731{
732 switch (attr) {
733 case VIRTIO_SCSI_S_SIMPLE:
734 return TCM_SIMPLE_TAG;
735 case VIRTIO_SCSI_S_ORDERED:
736 return TCM_ORDERED_TAG;
737 case VIRTIO_SCSI_S_HEAD:
738 return TCM_HEAD_TAG;
739 case VIRTIO_SCSI_S_ACA:
740 return TCM_ACA_TAG;
741 default:
742 break;
743 }
744 return TCM_SIMPLE_TAG;
745}
746
747static void vhost_scsi_submission_work(struct work_struct *work)
748{
749 struct vhost_scsi_cmd *cmd =
750 container_of(work, struct vhost_scsi_cmd, work);
751 struct vhost_scsi_nexus *tv_nexus;
752 struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
753 struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
754 int rc;
755
756 /* FIXME: BIDI operation */
757 if (cmd->tvc_sgl_count) {
758 sg_ptr = cmd->tvc_sgl;
759
760 if (cmd->tvc_prot_sgl_count)
761 sg_prot_ptr = cmd->tvc_prot_sgl;
762 else
763 se_cmd->prot_pto = true;
764 } else {
765 sg_ptr = NULL;
766 }
767 tv_nexus = cmd->tvc_nexus;
768
769 se_cmd->tag = 0;
770 rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
771 cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
772 cmd->tvc_lun, cmd->tvc_exp_data_len,
773 vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
774 cmd->tvc_data_direction, TARGET_SCF_ACK_KREF,
775 sg_ptr, cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
776 cmd->tvc_prot_sgl_count);
777 if (rc < 0) {
778 transport_send_check_condition_and_sense(se_cmd,
779 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
780 transport_generic_free_cmd(se_cmd, 0);
781 }
782}
783
784static void
785vhost_scsi_send_bad_target(struct vhost_scsi *vs,
786 struct vhost_virtqueue *vq,
787 int head, unsigned out)
788{
789 struct virtio_scsi_cmd_resp __user *resp;
790 struct virtio_scsi_cmd_resp rsp;
791 int ret;
792
793 memset(&rsp, 0, sizeof(rsp));
794 rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
795 resp = vq->iov[out].iov_base;
796 ret = __copy_to_user(resp, &rsp, sizeof(rsp));
797 if (!ret)
798 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
799 else
800 pr_err("Faulted on virtio_scsi_cmd_resp\n");
801}
802
803static void
804vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
805{
806 struct vhost_scsi_tpg **vs_tpg, *tpg;
807 struct virtio_scsi_cmd_req v_req;
808 struct virtio_scsi_cmd_req_pi v_req_pi;
809 struct vhost_scsi_cmd *cmd;
810 struct iov_iter out_iter, in_iter, prot_iter, data_iter;
811 u64 tag;
812 u32 exp_data_len, data_direction;
813 unsigned int out = 0, in = 0;
814 int head, ret, prot_bytes;
815 size_t req_size, rsp_size = sizeof(struct virtio_scsi_cmd_resp);
816 size_t out_size, in_size;
817 u16 lun;
818 u8 *target, *lunp, task_attr;
819 bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
820 void *req, *cdb;
821
822 mutex_lock(&vq->mutex);
823 /*
824 * We can handle the vq only after the endpoint is setup by calling the
825 * VHOST_SCSI_SET_ENDPOINT ioctl.
826 */
827 vs_tpg = vq->private_data;
828 if (!vs_tpg)
829 goto out;
830
831 vhost_disable_notify(&vs->dev, vq);
832
833 for (;;) {
834 head = vhost_get_vq_desc(vq, vq->iov,
835 ARRAY_SIZE(vq->iov), &out, &in,
836 NULL, NULL);
837 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
838 head, out, in);
839 /* On error, stop handling until the next kick. */
840 if (unlikely(head < 0))
841 break;
842 /* Nothing new? Wait for eventfd to tell us they refilled. */
843 if (head == vq->num) {
844 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
845 vhost_disable_notify(&vs->dev, vq);
846 continue;
847 }
848 break;
849 }
850 /*
851 * Check for a sane response buffer so we can report early
852 * errors back to the guest.
853 */
854 if (unlikely(vq->iov[out].iov_len < rsp_size)) {
855 vq_err(vq, "Expecting at least virtio_scsi_cmd_resp"
856 " size, got %zu bytes\n", vq->iov[out].iov_len);
857 break;
858 }
859 /*
860 * Setup pointers and values based upon different virtio-scsi
861 * request header if T10_PI is enabled in KVM guest.
862 */
863 if (t10_pi) {
864 req = &v_req_pi;
865 req_size = sizeof(v_req_pi);
866 lunp = &v_req_pi.lun[0];
867 target = &v_req_pi.lun[1];
868 } else {
869 req = &v_req;
870 req_size = sizeof(v_req);
871 lunp = &v_req.lun[0];
872 target = &v_req.lun[1];
873 }
874 /*
875 * FIXME: Not correct for BIDI operation
876 */
877 out_size = iov_length(vq->iov, out);
878 in_size = iov_length(&vq->iov[out], in);
879
880 /*
881 * Copy over the virtio-scsi request header, which for a
882 * ANY_LAYOUT enabled guest may span multiple iovecs, or a
883 * single iovec may contain both the header + outgoing
884 * WRITE payloads.
885 *
886 * copy_from_iter() will advance out_iter, so that it will
887 * point at the start of the outgoing WRITE payload, if
888 * DMA_TO_DEVICE is set.
889 */
890 iov_iter_init(&out_iter, WRITE, vq->iov, out, out_size);
891
892 if (unlikely(!copy_from_iter_full(req, req_size, &out_iter))) {
893 vq_err(vq, "Faulted on copy_from_iter\n");
894 vhost_scsi_send_bad_target(vs, vq, head, out);
895 continue;
896 }
897 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
898 if (unlikely(*lunp != 1)) {
899 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *lunp);
900 vhost_scsi_send_bad_target(vs, vq, head, out);
901 continue;
902 }
903
904 tpg = READ_ONCE(vs_tpg[*target]);
905 if (unlikely(!tpg)) {
906 /* Target does not exist, fail the request */
907 vhost_scsi_send_bad_target(vs, vq, head, out);
908 continue;
909 }
910 /*
911 * Determine data_direction by calculating the total outgoing
912 * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
913 * response headers respectively.
914 *
915 * For DMA_TO_DEVICE this is out_iter, which is already pointing
916 * to the right place.
917 *
918 * For DMA_FROM_DEVICE, the iovec will be just past the end
919 * of the virtio-scsi response header in either the same
920 * or immediately following iovec.
921 *
922 * Any associated T10_PI bytes for the outgoing / incoming
923 * payloads are included in calculation of exp_data_len here.
924 */
925 prot_bytes = 0;
926
927 if (out_size > req_size) {
928 data_direction = DMA_TO_DEVICE;
929 exp_data_len = out_size - req_size;
930 data_iter = out_iter;
931 } else if (in_size > rsp_size) {
932 data_direction = DMA_FROM_DEVICE;
933 exp_data_len = in_size - rsp_size;
934
935 iov_iter_init(&in_iter, READ, &vq->iov[out], in,
936 rsp_size + exp_data_len);
937 iov_iter_advance(&in_iter, rsp_size);
938 data_iter = in_iter;
939 } else {
940 data_direction = DMA_NONE;
941 exp_data_len = 0;
942 }
943 /*
944 * If T10_PI header + payload is present, setup prot_iter values
945 * and recalculate data_iter for vhost_scsi_mapal() mapping to
946 * host scatterlists via get_user_pages_fast().
947 */
948 if (t10_pi) {
949 if (v_req_pi.pi_bytesout) {
950 if (data_direction != DMA_TO_DEVICE) {
951 vq_err(vq, "Received non zero pi_bytesout,"
952 " but wrong data_direction\n");
953 vhost_scsi_send_bad_target(vs, vq, head, out);
954 continue;
955 }
956 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
957 } else if (v_req_pi.pi_bytesin) {
958 if (data_direction != DMA_FROM_DEVICE) {
959 vq_err(vq, "Received non zero pi_bytesin,"
960 " but wrong data_direction\n");
961 vhost_scsi_send_bad_target(vs, vq, head, out);
962 continue;
963 }
964 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
965 }
966 /*
967 * Set prot_iter to data_iter, and advance past any
968 * preceeding prot_bytes that may be present.
969 *
970 * Also fix up the exp_data_len to reflect only the
971 * actual data payload length.
972 */
973 if (prot_bytes) {
974 exp_data_len -= prot_bytes;
975 prot_iter = data_iter;
976 iov_iter_advance(&data_iter, prot_bytes);
977 }
978 tag = vhost64_to_cpu(vq, v_req_pi.tag);
979 task_attr = v_req_pi.task_attr;
980 cdb = &v_req_pi.cdb[0];
981 lun = ((v_req_pi.lun[2] << 8) | v_req_pi.lun[3]) & 0x3FFF;
982 } else {
983 tag = vhost64_to_cpu(vq, v_req.tag);
984 task_attr = v_req.task_attr;
985 cdb = &v_req.cdb[0];
986 lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
987 }
988 /*
989 * Check that the received CDB size does not exceeded our
990 * hardcoded max for vhost-scsi, then get a pre-allocated
991 * cmd descriptor for the new virtio-scsi tag.
992 *
993 * TODO what if cdb was too small for varlen cdb header?
994 */
995 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
996 vq_err(vq, "Received SCSI CDB with command_size: %d that"
997 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
998 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
999 vhost_scsi_send_bad_target(vs, vq, head, out);
1000 continue;
1001 }
1002 cmd = vhost_scsi_get_tag(vq, tpg, cdb, tag, lun, task_attr,
1003 exp_data_len + prot_bytes,
1004 data_direction);
1005 if (IS_ERR(cmd)) {
1006 vq_err(vq, "vhost_scsi_get_tag failed %ld\n",
1007 PTR_ERR(cmd));
1008 vhost_scsi_send_bad_target(vs, vq, head, out);
1009 continue;
1010 }
1011 cmd->tvc_vhost = vs;
1012 cmd->tvc_vq = vq;
1013 cmd->tvc_resp_iov = vq->iov[out];
1014 cmd->tvc_in_iovs = in;
1015
1016 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1017 cmd->tvc_cdb[0], cmd->tvc_lun);
1018 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1019 " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1020
1021 if (data_direction != DMA_NONE) {
1022 ret = vhost_scsi_mapal(cmd,
1023 prot_bytes, &prot_iter,
1024 exp_data_len, &data_iter);
1025 if (unlikely(ret)) {
1026 vq_err(vq, "Failed to map iov to sgl\n");
1027 vhost_scsi_release_cmd(&cmd->tvc_se_cmd);
1028 vhost_scsi_send_bad_target(vs, vq, head, out);
1029 continue;
1030 }
1031 }
1032 /*
1033 * Save the descriptor from vhost_get_vq_desc() to be used to
1034 * complete the virtio-scsi request in TCM callback context via
1035 * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1036 */
1037 cmd->tvc_vq_desc = head;
1038 /*
1039 * Dispatch cmd descriptor for cmwq execution in process
1040 * context provided by vhost_scsi_workqueue. This also ensures
1041 * cmd is executed on the same kworker CPU as this vhost
1042 * thread to gain positive L2 cache locality effects.
1043 */
1044 INIT_WORK(&cmd->work, vhost_scsi_submission_work);
1045 queue_work(vhost_scsi_workqueue, &cmd->work);
1046 }
1047out:
1048 mutex_unlock(&vq->mutex);
1049}
1050
1051static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1052{
1053 pr_debug("%s: The handling func for control queue.\n", __func__);
1054}
1055
1056static void
1057vhost_scsi_send_evt(struct vhost_scsi *vs,
1058 struct vhost_scsi_tpg *tpg,
1059 struct se_lun *lun,
1060 u32 event,
1061 u32 reason)
1062{
1063 struct vhost_scsi_evt *evt;
1064
1065 evt = vhost_scsi_allocate_evt(vs, event, reason);
1066 if (!evt)
1067 return;
1068
1069 if (tpg && lun) {
1070 /* TODO: share lun setup code with virtio-scsi.ko */
1071 /*
1072 * Note: evt->event is zeroed when we allocate it and
1073 * lun[4-7] need to be zero according to virtio-scsi spec.
1074 */
1075 evt->event.lun[0] = 0x01;
1076 evt->event.lun[1] = tpg->tport_tpgt;
1077 if (lun->unpacked_lun >= 256)
1078 evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1079 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1080 }
1081
1082 llist_add(&evt->list, &vs->vs_event_list);
1083 vhost_work_queue(&vs->dev, &vs->vs_event_work);
1084}
1085
1086static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1087{
1088 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1089 poll.work);
1090 struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1091
1092 mutex_lock(&vq->mutex);
1093 if (!vq->private_data)
1094 goto out;
1095
1096 if (vs->vs_events_missed)
1097 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1098out:
1099 mutex_unlock(&vq->mutex);
1100}
1101
1102static void vhost_scsi_handle_kick(struct vhost_work *work)
1103{
1104 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1105 poll.work);
1106 struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1107
1108 vhost_scsi_handle_vq(vs, vq);
1109}
1110
1111static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1112{
1113 vhost_poll_flush(&vs->vqs[index].vq.poll);
1114}
1115
1116/* Callers must hold dev mutex */
1117static void vhost_scsi_flush(struct vhost_scsi *vs)
1118{
1119 struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1120 int i;
1121
1122 /* Init new inflight and remember the old inflight */
1123 vhost_scsi_init_inflight(vs, old_inflight);
1124
1125 /*
1126 * The inflight->kref was initialized to 1. We decrement it here to
1127 * indicate the start of the flush operation so that it will reach 0
1128 * when all the reqs are finished.
1129 */
1130 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1131 kref_put(&old_inflight[i]->kref, vhost_scsi_done_inflight);
1132
1133 /* Flush both the vhost poll and vhost work */
1134 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1135 vhost_scsi_flush_vq(vs, i);
1136 vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1137 vhost_work_flush(&vs->dev, &vs->vs_event_work);
1138
1139 /* Wait for all reqs issued before the flush to be finished */
1140 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1141 wait_for_completion(&old_inflight[i]->comp);
1142}
1143
1144/*
1145 * Called from vhost_scsi_ioctl() context to walk the list of available
1146 * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1147 *
1148 * The lock nesting rule is:
1149 * vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1150 */
1151static int
1152vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1153 struct vhost_scsi_target *t)
1154{
1155 struct se_portal_group *se_tpg;
1156 struct vhost_scsi_tport *tv_tport;
1157 struct vhost_scsi_tpg *tpg;
1158 struct vhost_scsi_tpg **vs_tpg;
1159 struct vhost_virtqueue *vq;
1160 int index, ret, i, len;
1161 bool match = false;
1162
1163 mutex_lock(&vhost_scsi_mutex);
1164 mutex_lock(&vs->dev.mutex);
1165
1166 /* Verify that ring has been setup correctly. */
1167 for (index = 0; index < vs->dev.nvqs; ++index) {
1168 /* Verify that ring has been setup correctly. */
1169 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1170 ret = -EFAULT;
1171 goto out;
1172 }
1173 }
1174
1175 len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1176 vs_tpg = kzalloc(len, GFP_KERNEL);
1177 if (!vs_tpg) {
1178 ret = -ENOMEM;
1179 goto out;
1180 }
1181 if (vs->vs_tpg)
1182 memcpy(vs_tpg, vs->vs_tpg, len);
1183
1184 list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1185 mutex_lock(&tpg->tv_tpg_mutex);
1186 if (!tpg->tpg_nexus) {
1187 mutex_unlock(&tpg->tv_tpg_mutex);
1188 continue;
1189 }
1190 if (tpg->tv_tpg_vhost_count != 0) {
1191 mutex_unlock(&tpg->tv_tpg_mutex);
1192 continue;
1193 }
1194 tv_tport = tpg->tport;
1195
1196 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1197 if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1198 kfree(vs_tpg);
1199 mutex_unlock(&tpg->tv_tpg_mutex);
1200 ret = -EEXIST;
1201 goto out;
1202 }
1203 /*
1204 * In order to ensure individual vhost-scsi configfs
1205 * groups cannot be removed while in use by vhost ioctl,
1206 * go ahead and take an explicit se_tpg->tpg_group.cg_item
1207 * dependency now.
1208 */
1209 se_tpg = &tpg->se_tpg;
1210 ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1211 if (ret) {
1212 pr_warn("configfs_depend_item() failed: %d\n", ret);
1213 kfree(vs_tpg);
1214 mutex_unlock(&tpg->tv_tpg_mutex);
1215 goto out;
1216 }
1217 tpg->tv_tpg_vhost_count++;
1218 tpg->vhost_scsi = vs;
1219 vs_tpg[tpg->tport_tpgt] = tpg;
1220 smp_mb__after_atomic();
1221 match = true;
1222 }
1223 mutex_unlock(&tpg->tv_tpg_mutex);
1224 }
1225
1226 if (match) {
1227 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1228 sizeof(vs->vs_vhost_wwpn));
1229 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1230 vq = &vs->vqs[i].vq;
1231 mutex_lock(&vq->mutex);
1232 vq->private_data = vs_tpg;
1233 vhost_vq_init_access(vq);
1234 mutex_unlock(&vq->mutex);
1235 }
1236 ret = 0;
1237 } else {
1238 ret = -EEXIST;
1239 }
1240
1241 /*
1242 * Act as synchronize_rcu to make sure access to
1243 * old vs->vs_tpg is finished.
1244 */
1245 vhost_scsi_flush(vs);
1246 kfree(vs->vs_tpg);
1247 vs->vs_tpg = vs_tpg;
1248
1249out:
1250 mutex_unlock(&vs->dev.mutex);
1251 mutex_unlock(&vhost_scsi_mutex);
1252 return ret;
1253}
1254
1255static int
1256vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1257 struct vhost_scsi_target *t)
1258{
1259 struct se_portal_group *se_tpg;
1260 struct vhost_scsi_tport *tv_tport;
1261 struct vhost_scsi_tpg *tpg;
1262 struct vhost_virtqueue *vq;
1263 bool match = false;
1264 int index, ret, i;
1265 u8 target;
1266
1267 mutex_lock(&vhost_scsi_mutex);
1268 mutex_lock(&vs->dev.mutex);
1269 /* Verify that ring has been setup correctly. */
1270 for (index = 0; index < vs->dev.nvqs; ++index) {
1271 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1272 ret = -EFAULT;
1273 goto err_dev;
1274 }
1275 }
1276
1277 if (!vs->vs_tpg) {
1278 ret = 0;
1279 goto err_dev;
1280 }
1281
1282 for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1283 target = i;
1284 tpg = vs->vs_tpg[target];
1285 if (!tpg)
1286 continue;
1287
1288 mutex_lock(&tpg->tv_tpg_mutex);
1289 tv_tport = tpg->tport;
1290 if (!tv_tport) {
1291 ret = -ENODEV;
1292 goto err_tpg;
1293 }
1294
1295 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1296 pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1297 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1298 tv_tport->tport_name, tpg->tport_tpgt,
1299 t->vhost_wwpn, t->vhost_tpgt);
1300 ret = -EINVAL;
1301 goto err_tpg;
1302 }
1303 tpg->tv_tpg_vhost_count--;
1304 tpg->vhost_scsi = NULL;
1305 vs->vs_tpg[target] = NULL;
1306 match = true;
1307 mutex_unlock(&tpg->tv_tpg_mutex);
1308 /*
1309 * Release se_tpg->tpg_group.cg_item configfs dependency now
1310 * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1311 */
1312 se_tpg = &tpg->se_tpg;
1313 target_undepend_item(&se_tpg->tpg_group.cg_item);
1314 }
1315 if (match) {
1316 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1317 vq = &vs->vqs[i].vq;
1318 mutex_lock(&vq->mutex);
1319 vq->private_data = NULL;
1320 mutex_unlock(&vq->mutex);
1321 }
1322 }
1323 /*
1324 * Act as synchronize_rcu to make sure access to
1325 * old vs->vs_tpg is finished.
1326 */
1327 vhost_scsi_flush(vs);
1328 kfree(vs->vs_tpg);
1329 vs->vs_tpg = NULL;
1330 WARN_ON(vs->vs_events_nr);
1331 mutex_unlock(&vs->dev.mutex);
1332 mutex_unlock(&vhost_scsi_mutex);
1333 return 0;
1334
1335err_tpg:
1336 mutex_unlock(&tpg->tv_tpg_mutex);
1337err_dev:
1338 mutex_unlock(&vs->dev.mutex);
1339 mutex_unlock(&vhost_scsi_mutex);
1340 return ret;
1341}
1342
1343static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1344{
1345 struct vhost_virtqueue *vq;
1346 int i;
1347
1348 if (features & ~VHOST_SCSI_FEATURES)
1349 return -EOPNOTSUPP;
1350
1351 mutex_lock(&vs->dev.mutex);
1352 if ((features & (1 << VHOST_F_LOG_ALL)) &&
1353 !vhost_log_access_ok(&vs->dev)) {
1354 mutex_unlock(&vs->dev.mutex);
1355 return -EFAULT;
1356 }
1357
1358 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1359 vq = &vs->vqs[i].vq;
1360 mutex_lock(&vq->mutex);
1361 vq->acked_features = features;
1362 mutex_unlock(&vq->mutex);
1363 }
1364 mutex_unlock(&vs->dev.mutex);
1365 return 0;
1366}
1367
1368static int vhost_scsi_open(struct inode *inode, struct file *f)
1369{
1370 struct vhost_scsi *vs;
1371 struct vhost_virtqueue **vqs;
1372 int r = -ENOMEM, i;
1373
1374 vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
1375 if (!vs) {
1376 vs = vzalloc(sizeof(*vs));
1377 if (!vs)
1378 goto err_vs;
1379 }
1380
1381 vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1382 if (!vqs)
1383 goto err_vqs;
1384
1385 vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1386 vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1387
1388 vs->vs_events_nr = 0;
1389 vs->vs_events_missed = false;
1390
1391 vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1392 vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1393 vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1394 vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1395 for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1396 vqs[i] = &vs->vqs[i].vq;
1397 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1398 }
1399 vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1400
1401 vhost_scsi_init_inflight(vs, NULL);
1402
1403 f->private_data = vs;
1404 return 0;
1405
1406err_vqs:
1407 kvfree(vs);
1408err_vs:
1409 return r;
1410}
1411
1412static int vhost_scsi_release(struct inode *inode, struct file *f)
1413{
1414 struct vhost_scsi *vs = f->private_data;
1415 struct vhost_scsi_target t;
1416
1417 mutex_lock(&vs->dev.mutex);
1418 memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1419 mutex_unlock(&vs->dev.mutex);
1420 vhost_scsi_clear_endpoint(vs, &t);
1421 vhost_dev_stop(&vs->dev);
1422 vhost_dev_cleanup(&vs->dev);
1423 /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1424 vhost_scsi_flush(vs);
1425 kfree(vs->dev.vqs);
1426 kvfree(vs);
1427 return 0;
1428}
1429
1430static long
1431vhost_scsi_ioctl(struct file *f,
1432 unsigned int ioctl,
1433 unsigned long arg)
1434{
1435 struct vhost_scsi *vs = f->private_data;
1436 struct vhost_scsi_target backend;
1437 void __user *argp = (void __user *)arg;
1438 u64 __user *featurep = argp;
1439 u32 __user *eventsp = argp;
1440 u32 events_missed;
1441 u64 features;
1442 int r, abi_version = VHOST_SCSI_ABI_VERSION;
1443 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1444
1445 switch (ioctl) {
1446 case VHOST_SCSI_SET_ENDPOINT:
1447 if (copy_from_user(&backend, argp, sizeof backend))
1448 return -EFAULT;
1449 if (backend.reserved != 0)
1450 return -EOPNOTSUPP;
1451
1452 return vhost_scsi_set_endpoint(vs, &backend);
1453 case VHOST_SCSI_CLEAR_ENDPOINT:
1454 if (copy_from_user(&backend, argp, sizeof backend))
1455 return -EFAULT;
1456 if (backend.reserved != 0)
1457 return -EOPNOTSUPP;
1458
1459 return vhost_scsi_clear_endpoint(vs, &backend);
1460 case VHOST_SCSI_GET_ABI_VERSION:
1461 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1462 return -EFAULT;
1463 return 0;
1464 case VHOST_SCSI_SET_EVENTS_MISSED:
1465 if (get_user(events_missed, eventsp))
1466 return -EFAULT;
1467 mutex_lock(&vq->mutex);
1468 vs->vs_events_missed = events_missed;
1469 mutex_unlock(&vq->mutex);
1470 return 0;
1471 case VHOST_SCSI_GET_EVENTS_MISSED:
1472 mutex_lock(&vq->mutex);
1473 events_missed = vs->vs_events_missed;
1474 mutex_unlock(&vq->mutex);
1475 if (put_user(events_missed, eventsp))
1476 return -EFAULT;
1477 return 0;
1478 case VHOST_GET_FEATURES:
1479 features = VHOST_SCSI_FEATURES;
1480 if (copy_to_user(featurep, &features, sizeof features))
1481 return -EFAULT;
1482 return 0;
1483 case VHOST_SET_FEATURES:
1484 if (copy_from_user(&features, featurep, sizeof features))
1485 return -EFAULT;
1486 return vhost_scsi_set_features(vs, features);
1487 default:
1488 mutex_lock(&vs->dev.mutex);
1489 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1490 /* TODO: flush backend after dev ioctl. */
1491 if (r == -ENOIOCTLCMD)
1492 r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1493 mutex_unlock(&vs->dev.mutex);
1494 return r;
1495 }
1496}
1497
1498#ifdef CONFIG_COMPAT
1499static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1500 unsigned long arg)
1501{
1502 return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1503}
1504#endif
1505
1506static const struct file_operations vhost_scsi_fops = {
1507 .owner = THIS_MODULE,
1508 .release = vhost_scsi_release,
1509 .unlocked_ioctl = vhost_scsi_ioctl,
1510#ifdef CONFIG_COMPAT
1511 .compat_ioctl = vhost_scsi_compat_ioctl,
1512#endif
1513 .open = vhost_scsi_open,
1514 .llseek = noop_llseek,
1515};
1516
1517static struct miscdevice vhost_scsi_misc = {
1518 MISC_DYNAMIC_MINOR,
1519 "vhost-scsi",
1520 &vhost_scsi_fops,
1521};
1522
1523static int __init vhost_scsi_register(void)
1524{
1525 return misc_register(&vhost_scsi_misc);
1526}
1527
1528static void vhost_scsi_deregister(void)
1529{
1530 misc_deregister(&vhost_scsi_misc);
1531}
1532
1533static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1534{
1535 switch (tport->tport_proto_id) {
1536 case SCSI_PROTOCOL_SAS:
1537 return "SAS";
1538 case SCSI_PROTOCOL_FCP:
1539 return "FCP";
1540 case SCSI_PROTOCOL_ISCSI:
1541 return "iSCSI";
1542 default:
1543 break;
1544 }
1545
1546 return "Unknown";
1547}
1548
1549static void
1550vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1551 struct se_lun *lun, bool plug)
1552{
1553
1554 struct vhost_scsi *vs = tpg->vhost_scsi;
1555 struct vhost_virtqueue *vq;
1556 u32 reason;
1557
1558 if (!vs)
1559 return;
1560
1561 mutex_lock(&vs->dev.mutex);
1562
1563 if (plug)
1564 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1565 else
1566 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1567
1568 vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1569 mutex_lock(&vq->mutex);
1570 if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
1571 vhost_scsi_send_evt(vs, tpg, lun,
1572 VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1573 mutex_unlock(&vq->mutex);
1574 mutex_unlock(&vs->dev.mutex);
1575}
1576
1577static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1578{
1579 vhost_scsi_do_plug(tpg, lun, true);
1580}
1581
1582static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1583{
1584 vhost_scsi_do_plug(tpg, lun, false);
1585}
1586
1587static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
1588 struct se_lun *lun)
1589{
1590 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1591 struct vhost_scsi_tpg, se_tpg);
1592
1593 mutex_lock(&vhost_scsi_mutex);
1594
1595 mutex_lock(&tpg->tv_tpg_mutex);
1596 tpg->tv_tpg_port_count++;
1597 mutex_unlock(&tpg->tv_tpg_mutex);
1598
1599 vhost_scsi_hotplug(tpg, lun);
1600
1601 mutex_unlock(&vhost_scsi_mutex);
1602
1603 return 0;
1604}
1605
1606static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
1607 struct se_lun *lun)
1608{
1609 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1610 struct vhost_scsi_tpg, se_tpg);
1611
1612 mutex_lock(&vhost_scsi_mutex);
1613
1614 mutex_lock(&tpg->tv_tpg_mutex);
1615 tpg->tv_tpg_port_count--;
1616 mutex_unlock(&tpg->tv_tpg_mutex);
1617
1618 vhost_scsi_hotunplug(tpg, lun);
1619
1620 mutex_unlock(&vhost_scsi_mutex);
1621}
1622
1623static void vhost_scsi_free_cmd_map_res(struct se_session *se_sess)
1624{
1625 struct vhost_scsi_cmd *tv_cmd;
1626 unsigned int i;
1627
1628 if (!se_sess->sess_cmd_map)
1629 return;
1630
1631 for (i = 0; i < VHOST_SCSI_DEFAULT_TAGS; i++) {
1632 tv_cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[i];
1633
1634 kfree(tv_cmd->tvc_sgl);
1635 kfree(tv_cmd->tvc_prot_sgl);
1636 kfree(tv_cmd->tvc_upages);
1637 }
1638}
1639
1640static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
1641 struct config_item *item, const char *page, size_t count)
1642{
1643 struct se_portal_group *se_tpg = attrib_to_tpg(item);
1644 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1645 struct vhost_scsi_tpg, se_tpg);
1646 unsigned long val;
1647 int ret = kstrtoul(page, 0, &val);
1648
1649 if (ret) {
1650 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
1651 return ret;
1652 }
1653 if (val != 0 && val != 1 && val != 3) {
1654 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
1655 return -EINVAL;
1656 }
1657 tpg->tv_fabric_prot_type = val;
1658
1659 return count;
1660}
1661
1662static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
1663 struct config_item *item, char *page)
1664{
1665 struct se_portal_group *se_tpg = attrib_to_tpg(item);
1666 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1667 struct vhost_scsi_tpg, se_tpg);
1668
1669 return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
1670}
1671
1672CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
1673
1674static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
1675 &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
1676 NULL,
1677};
1678
1679static int vhost_scsi_nexus_cb(struct se_portal_group *se_tpg,
1680 struct se_session *se_sess, void *p)
1681{
1682 struct vhost_scsi_cmd *tv_cmd;
1683 unsigned int i;
1684
1685 for (i = 0; i < VHOST_SCSI_DEFAULT_TAGS; i++) {
1686 tv_cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[i];
1687
1688 tv_cmd->tvc_sgl = kzalloc(sizeof(struct scatterlist) *
1689 VHOST_SCSI_PREALLOC_SGLS, GFP_KERNEL);
1690 if (!tv_cmd->tvc_sgl) {
1691 pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1692 goto out;
1693 }
1694
1695 tv_cmd->tvc_upages = kzalloc(sizeof(struct page *) *
1696 VHOST_SCSI_PREALLOC_UPAGES, GFP_KERNEL);
1697 if (!tv_cmd->tvc_upages) {
1698 pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1699 goto out;
1700 }
1701
1702 tv_cmd->tvc_prot_sgl = kzalloc(sizeof(struct scatterlist) *
1703 VHOST_SCSI_PREALLOC_PROT_SGLS, GFP_KERNEL);
1704 if (!tv_cmd->tvc_prot_sgl) {
1705 pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1706 goto out;
1707 }
1708 }
1709 return 0;
1710out:
1711 vhost_scsi_free_cmd_map_res(se_sess);
1712 return -ENOMEM;
1713}
1714
1715static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
1716 const char *name)
1717{
1718 struct vhost_scsi_nexus *tv_nexus;
1719
1720 mutex_lock(&tpg->tv_tpg_mutex);
1721 if (tpg->tpg_nexus) {
1722 mutex_unlock(&tpg->tv_tpg_mutex);
1723 pr_debug("tpg->tpg_nexus already exists\n");
1724 return -EEXIST;
1725 }
1726
1727 tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
1728 if (!tv_nexus) {
1729 mutex_unlock(&tpg->tv_tpg_mutex);
1730 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
1731 return -ENOMEM;
1732 }
1733 /*
1734 * Since we are running in 'demo mode' this call with generate a
1735 * struct se_node_acl for the vhost_scsi struct se_portal_group with
1736 * the SCSI Initiator port name of the passed configfs group 'name'.
1737 */
1738 tv_nexus->tvn_se_sess = target_alloc_session(&tpg->se_tpg,
1739 VHOST_SCSI_DEFAULT_TAGS,
1740 sizeof(struct vhost_scsi_cmd),
1741 TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
1742 (unsigned char *)name, tv_nexus,
1743 vhost_scsi_nexus_cb);
1744 if (IS_ERR(tv_nexus->tvn_se_sess)) {
1745 mutex_unlock(&tpg->tv_tpg_mutex);
1746 kfree(tv_nexus);
1747 return -ENOMEM;
1748 }
1749 tpg->tpg_nexus = tv_nexus;
1750
1751 mutex_unlock(&tpg->tv_tpg_mutex);
1752 return 0;
1753}
1754
1755static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
1756{
1757 struct se_session *se_sess;
1758 struct vhost_scsi_nexus *tv_nexus;
1759
1760 mutex_lock(&tpg->tv_tpg_mutex);
1761 tv_nexus = tpg->tpg_nexus;
1762 if (!tv_nexus) {
1763 mutex_unlock(&tpg->tv_tpg_mutex);
1764 return -ENODEV;
1765 }
1766
1767 se_sess = tv_nexus->tvn_se_sess;
1768 if (!se_sess) {
1769 mutex_unlock(&tpg->tv_tpg_mutex);
1770 return -ENODEV;
1771 }
1772
1773 if (tpg->tv_tpg_port_count != 0) {
1774 mutex_unlock(&tpg->tv_tpg_mutex);
1775 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1776 " active TPG port count: %d\n",
1777 tpg->tv_tpg_port_count);
1778 return -EBUSY;
1779 }
1780
1781 if (tpg->tv_tpg_vhost_count != 0) {
1782 mutex_unlock(&tpg->tv_tpg_mutex);
1783 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1784 " active TPG vhost count: %d\n",
1785 tpg->tv_tpg_vhost_count);
1786 return -EBUSY;
1787 }
1788
1789 pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1790 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
1791 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1792
1793 vhost_scsi_free_cmd_map_res(se_sess);
1794 /*
1795 * Release the SCSI I_T Nexus to the emulated vhost Target Port
1796 */
1797 transport_deregister_session(tv_nexus->tvn_se_sess);
1798 tpg->tpg_nexus = NULL;
1799 mutex_unlock(&tpg->tv_tpg_mutex);
1800
1801 kfree(tv_nexus);
1802 return 0;
1803}
1804
1805static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
1806{
1807 struct se_portal_group *se_tpg = to_tpg(item);
1808 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1809 struct vhost_scsi_tpg, se_tpg);
1810 struct vhost_scsi_nexus *tv_nexus;
1811 ssize_t ret;
1812
1813 mutex_lock(&tpg->tv_tpg_mutex);
1814 tv_nexus = tpg->tpg_nexus;
1815 if (!tv_nexus) {
1816 mutex_unlock(&tpg->tv_tpg_mutex);
1817 return -ENODEV;
1818 }
1819 ret = snprintf(page, PAGE_SIZE, "%s\n",
1820 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1821 mutex_unlock(&tpg->tv_tpg_mutex);
1822
1823 return ret;
1824}
1825
1826static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
1827 const char *page, size_t count)
1828{
1829 struct se_portal_group *se_tpg = to_tpg(item);
1830 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1831 struct vhost_scsi_tpg, se_tpg);
1832 struct vhost_scsi_tport *tport_wwn = tpg->tport;
1833 unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
1834 int ret;
1835 /*
1836 * Shutdown the active I_T nexus if 'NULL' is passed..
1837 */
1838 if (!strncmp(page, "NULL", 4)) {
1839 ret = vhost_scsi_drop_nexus(tpg);
1840 return (!ret) ? count : ret;
1841 }
1842 /*
1843 * Otherwise make sure the passed virtual Initiator port WWN matches
1844 * the fabric protocol_id set in vhost_scsi_make_tport(), and call
1845 * vhost_scsi_make_nexus().
1846 */
1847 if (strlen(page) >= VHOST_SCSI_NAMELEN) {
1848 pr_err("Emulated NAA Sas Address: %s, exceeds"
1849 " max: %d\n", page, VHOST_SCSI_NAMELEN);
1850 return -EINVAL;
1851 }
1852 snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
1853
1854 ptr = strstr(i_port, "naa.");
1855 if (ptr) {
1856 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1857 pr_err("Passed SAS Initiator Port %s does not"
1858 " match target port protoid: %s\n", i_port,
1859 vhost_scsi_dump_proto_id(tport_wwn));
1860 return -EINVAL;
1861 }
1862 port_ptr = &i_port[0];
1863 goto check_newline;
1864 }
1865 ptr = strstr(i_port, "fc.");
1866 if (ptr) {
1867 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1868 pr_err("Passed FCP Initiator Port %s does not"
1869 " match target port protoid: %s\n", i_port,
1870 vhost_scsi_dump_proto_id(tport_wwn));
1871 return -EINVAL;
1872 }
1873 port_ptr = &i_port[3]; /* Skip over "fc." */
1874 goto check_newline;
1875 }
1876 ptr = strstr(i_port, "iqn.");
1877 if (ptr) {
1878 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1879 pr_err("Passed iSCSI Initiator Port %s does not"
1880 " match target port protoid: %s\n", i_port,
1881 vhost_scsi_dump_proto_id(tport_wwn));
1882 return -EINVAL;
1883 }
1884 port_ptr = &i_port[0];
1885 goto check_newline;
1886 }
1887 pr_err("Unable to locate prefix for emulated Initiator Port:"
1888 " %s\n", i_port);
1889 return -EINVAL;
1890 /*
1891 * Clear any trailing newline for the NAA WWN
1892 */
1893check_newline:
1894 if (i_port[strlen(i_port)-1] == '\n')
1895 i_port[strlen(i_port)-1] = '\0';
1896
1897 ret = vhost_scsi_make_nexus(tpg, port_ptr);
1898 if (ret < 0)
1899 return ret;
1900
1901 return count;
1902}
1903
1904CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
1905
1906static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
1907 &vhost_scsi_tpg_attr_nexus,
1908 NULL,
1909};
1910
1911static struct se_portal_group *
1912vhost_scsi_make_tpg(struct se_wwn *wwn,
1913 struct config_group *group,
1914 const char *name)
1915{
1916 struct vhost_scsi_tport *tport = container_of(wwn,
1917 struct vhost_scsi_tport, tport_wwn);
1918
1919 struct vhost_scsi_tpg *tpg;
1920 u16 tpgt;
1921 int ret;
1922
1923 if (strstr(name, "tpgt_") != name)
1924 return ERR_PTR(-EINVAL);
1925 if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
1926 return ERR_PTR(-EINVAL);
1927
1928 tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
1929 if (!tpg) {
1930 pr_err("Unable to allocate struct vhost_scsi_tpg");
1931 return ERR_PTR(-ENOMEM);
1932 }
1933 mutex_init(&tpg->tv_tpg_mutex);
1934 INIT_LIST_HEAD(&tpg->tv_tpg_list);
1935 tpg->tport = tport;
1936 tpg->tport_tpgt = tpgt;
1937
1938 ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
1939 if (ret < 0) {
1940 kfree(tpg);
1941 return NULL;
1942 }
1943 mutex_lock(&vhost_scsi_mutex);
1944 list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
1945 mutex_unlock(&vhost_scsi_mutex);
1946
1947 return &tpg->se_tpg;
1948}
1949
1950static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
1951{
1952 struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1953 struct vhost_scsi_tpg, se_tpg);
1954
1955 mutex_lock(&vhost_scsi_mutex);
1956 list_del(&tpg->tv_tpg_list);
1957 mutex_unlock(&vhost_scsi_mutex);
1958 /*
1959 * Release the virtual I_T Nexus for this vhost TPG
1960 */
1961 vhost_scsi_drop_nexus(tpg);
1962 /*
1963 * Deregister the se_tpg from TCM..
1964 */
1965 core_tpg_deregister(se_tpg);
1966 kfree(tpg);
1967}
1968
1969static struct se_wwn *
1970vhost_scsi_make_tport(struct target_fabric_configfs *tf,
1971 struct config_group *group,
1972 const char *name)
1973{
1974 struct vhost_scsi_tport *tport;
1975 char *ptr;
1976 u64 wwpn = 0;
1977 int off = 0;
1978
1979 /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
1980 return ERR_PTR(-EINVAL); */
1981
1982 tport = kzalloc(sizeof(*tport), GFP_KERNEL);
1983 if (!tport) {
1984 pr_err("Unable to allocate struct vhost_scsi_tport");
1985 return ERR_PTR(-ENOMEM);
1986 }
1987 tport->tport_wwpn = wwpn;
1988 /*
1989 * Determine the emulated Protocol Identifier and Target Port Name
1990 * based on the incoming configfs directory name.
1991 */
1992 ptr = strstr(name, "naa.");
1993 if (ptr) {
1994 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1995 goto check_len;
1996 }
1997 ptr = strstr(name, "fc.");
1998 if (ptr) {
1999 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2000 off = 3; /* Skip over "fc." */
2001 goto check_len;
2002 }
2003 ptr = strstr(name, "iqn.");
2004 if (ptr) {
2005 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2006 goto check_len;
2007 }
2008
2009 pr_err("Unable to locate prefix for emulated Target Port:"
2010 " %s\n", name);
2011 kfree(tport);
2012 return ERR_PTR(-EINVAL);
2013
2014check_len:
2015 if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2016 pr_err("Emulated %s Address: %s, exceeds"
2017 " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2018 VHOST_SCSI_NAMELEN);
2019 kfree(tport);
2020 return ERR_PTR(-EINVAL);
2021 }
2022 snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2023
2024 pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2025 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2026
2027 return &tport->tport_wwn;
2028}
2029
2030static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2031{
2032 struct vhost_scsi_tport *tport = container_of(wwn,
2033 struct vhost_scsi_tport, tport_wwn);
2034
2035 pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2036 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2037 tport->tport_name);
2038
2039 kfree(tport);
2040}
2041
2042static ssize_t
2043vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2044{
2045 return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2046 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2047 utsname()->machine);
2048}
2049
2050CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2051
2052static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2053 &vhost_scsi_wwn_attr_version,
2054 NULL,
2055};
2056
2057static const struct target_core_fabric_ops vhost_scsi_ops = {
2058 .module = THIS_MODULE,
2059 .name = "vhost",
2060 .get_fabric_name = vhost_scsi_get_fabric_name,
2061 .tpg_get_wwn = vhost_scsi_get_fabric_wwn,
2062 .tpg_get_tag = vhost_scsi_get_tpgt,
2063 .tpg_check_demo_mode = vhost_scsi_check_true,
2064 .tpg_check_demo_mode_cache = vhost_scsi_check_true,
2065 .tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2066 .tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2067 .tpg_check_prot_fabric_only = vhost_scsi_check_prot_fabric_only,
2068 .tpg_get_inst_index = vhost_scsi_tpg_get_inst_index,
2069 .release_cmd = vhost_scsi_release_cmd,
2070 .check_stop_free = vhost_scsi_check_stop_free,
2071 .sess_get_index = vhost_scsi_sess_get_index,
2072 .sess_get_initiator_sid = NULL,
2073 .write_pending = vhost_scsi_write_pending,
2074 .write_pending_status = vhost_scsi_write_pending_status,
2075 .set_default_node_attributes = vhost_scsi_set_default_node_attrs,
2076 .get_cmd_state = vhost_scsi_get_cmd_state,
2077 .queue_data_in = vhost_scsi_queue_data_in,
2078 .queue_status = vhost_scsi_queue_status,
2079 .queue_tm_rsp = vhost_scsi_queue_tm_rsp,
2080 .aborted_task = vhost_scsi_aborted_task,
2081 /*
2082 * Setup callers for generic logic in target_core_fabric_configfs.c
2083 */
2084 .fabric_make_wwn = vhost_scsi_make_tport,
2085 .fabric_drop_wwn = vhost_scsi_drop_tport,
2086 .fabric_make_tpg = vhost_scsi_make_tpg,
2087 .fabric_drop_tpg = vhost_scsi_drop_tpg,
2088 .fabric_post_link = vhost_scsi_port_link,
2089 .fabric_pre_unlink = vhost_scsi_port_unlink,
2090
2091 .tfc_wwn_attrs = vhost_scsi_wwn_attrs,
2092 .tfc_tpg_base_attrs = vhost_scsi_tpg_attrs,
2093 .tfc_tpg_attrib_attrs = vhost_scsi_tpg_attrib_attrs,
2094};
2095
2096static int __init vhost_scsi_init(void)
2097{
2098 int ret = -ENOMEM;
2099
2100 pr_debug("TCM_VHOST fabric module %s on %s/%s"
2101 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2102 utsname()->machine);
2103
2104 /*
2105 * Use our own dedicated workqueue for submitting I/O into
2106 * target core to avoid contention within system_wq.
2107 */
2108 vhost_scsi_workqueue = alloc_workqueue("vhost_scsi", 0, 0);
2109 if (!vhost_scsi_workqueue)
2110 goto out;
2111
2112 ret = vhost_scsi_register();
2113 if (ret < 0)
2114 goto out_destroy_workqueue;
2115
2116 ret = target_register_template(&vhost_scsi_ops);
2117 if (ret < 0)
2118 goto out_vhost_scsi_deregister;
2119
2120 return 0;
2121
2122out_vhost_scsi_deregister:
2123 vhost_scsi_deregister();
2124out_destroy_workqueue:
2125 destroy_workqueue(vhost_scsi_workqueue);
2126out:
2127 return ret;
2128};
2129
2130static void vhost_scsi_exit(void)
2131{
2132 target_unregister_template(&vhost_scsi_ops);
2133 vhost_scsi_deregister();
2134 destroy_workqueue(vhost_scsi_workqueue);
2135};
2136
2137MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2138MODULE_ALIAS("tcm_vhost");
2139MODULE_LICENSE("GPL");
2140module_init(vhost_scsi_init);
2141module_exit(vhost_scsi_exit);