Merge tag 'amd-drm-next-5.13-2021-03-23' of https://gitlab.freedesktop.org/agd5f...
[linux-2.6-microblaze.git] / drivers / thunderbolt / xdomain.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Thunderbolt XDomain discovery protocol support
4  *
5  * Copyright (C) 2017, Intel Corporation
6  * Authors: Michael Jamet <michael.jamet@intel.com>
7  *          Mika Westerberg <mika.westerberg@linux.intel.com>
8  */
9
10 #include <linux/device.h>
11 #include <linux/delay.h>
12 #include <linux/kmod.h>
13 #include <linux/module.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/utsname.h>
16 #include <linux/uuid.h>
17 #include <linux/workqueue.h>
18
19 #include "tb.h"
20
21 #define XDOMAIN_DEFAULT_TIMEOUT                 5000 /* ms */
22 #define XDOMAIN_UUID_RETRIES                    10
23 #define XDOMAIN_PROPERTIES_RETRIES              60
24 #define XDOMAIN_PROPERTIES_CHANGED_RETRIES      10
25 #define XDOMAIN_BONDING_WAIT                    100  /* ms */
26
27 struct xdomain_request_work {
28         struct work_struct work;
29         struct tb_xdp_header *pkg;
30         struct tb *tb;
31 };
32
33 static bool tb_xdomain_enabled = true;
34 module_param_named(xdomain, tb_xdomain_enabled, bool, 0444);
35 MODULE_PARM_DESC(xdomain, "allow XDomain protocol (default: true)");
36
37 /* Serializes access to the properties and protocol handlers below */
38 static DEFINE_MUTEX(xdomain_lock);
39
40 /* Properties exposed to the remote domains */
41 static struct tb_property_dir *xdomain_property_dir;
42 static u32 *xdomain_property_block;
43 static u32 xdomain_property_block_len;
44 static u32 xdomain_property_block_gen;
45
46 /* Additional protocol handlers */
47 static LIST_HEAD(protocol_handlers);
48
49 /* UUID for XDomain discovery protocol: b638d70e-42ff-40bb-97c2-90e2c0b2ff07 */
50 static const uuid_t tb_xdp_uuid =
51         UUID_INIT(0xb638d70e, 0x42ff, 0x40bb,
52                   0x97, 0xc2, 0x90, 0xe2, 0xc0, 0xb2, 0xff, 0x07);
53
54 bool tb_is_xdomain_enabled(void)
55 {
56         return tb_xdomain_enabled && tb_acpi_is_xdomain_allowed();
57 }
58
59 static bool tb_xdomain_match(const struct tb_cfg_request *req,
60                              const struct ctl_pkg *pkg)
61 {
62         switch (pkg->frame.eof) {
63         case TB_CFG_PKG_ERROR:
64                 return true;
65
66         case TB_CFG_PKG_XDOMAIN_RESP: {
67                 const struct tb_xdp_header *res_hdr = pkg->buffer;
68                 const struct tb_xdp_header *req_hdr = req->request;
69
70                 if (pkg->frame.size < req->response_size / 4)
71                         return false;
72
73                 /* Make sure route matches */
74                 if ((res_hdr->xd_hdr.route_hi & ~BIT(31)) !=
75                      req_hdr->xd_hdr.route_hi)
76                         return false;
77                 if ((res_hdr->xd_hdr.route_lo) != req_hdr->xd_hdr.route_lo)
78                         return false;
79
80                 /* Check that the XDomain protocol matches */
81                 if (!uuid_equal(&res_hdr->uuid, &req_hdr->uuid))
82                         return false;
83
84                 return true;
85         }
86
87         default:
88                 return false;
89         }
90 }
91
92 static bool tb_xdomain_copy(struct tb_cfg_request *req,
93                             const struct ctl_pkg *pkg)
94 {
95         memcpy(req->response, pkg->buffer, req->response_size);
96         req->result.err = 0;
97         return true;
98 }
99
100 static void response_ready(void *data)
101 {
102         tb_cfg_request_put(data);
103 }
104
105 static int __tb_xdomain_response(struct tb_ctl *ctl, const void *response,
106                                  size_t size, enum tb_cfg_pkg_type type)
107 {
108         struct tb_cfg_request *req;
109
110         req = tb_cfg_request_alloc();
111         if (!req)
112                 return -ENOMEM;
113
114         req->match = tb_xdomain_match;
115         req->copy = tb_xdomain_copy;
116         req->request = response;
117         req->request_size = size;
118         req->request_type = type;
119
120         return tb_cfg_request(ctl, req, response_ready, req);
121 }
122
123 /**
124  * tb_xdomain_response() - Send a XDomain response message
125  * @xd: XDomain to send the message
126  * @response: Response to send
127  * @size: Size of the response
128  * @type: PDF type of the response
129  *
130  * This can be used to send a XDomain response message to the other
131  * domain. No response for the message is expected.
132  *
133  * Return: %0 in case of success and negative errno in case of failure
134  */
135 int tb_xdomain_response(struct tb_xdomain *xd, const void *response,
136                         size_t size, enum tb_cfg_pkg_type type)
137 {
138         return __tb_xdomain_response(xd->tb->ctl, response, size, type);
139 }
140 EXPORT_SYMBOL_GPL(tb_xdomain_response);
141
142 static int __tb_xdomain_request(struct tb_ctl *ctl, const void *request,
143         size_t request_size, enum tb_cfg_pkg_type request_type, void *response,
144         size_t response_size, enum tb_cfg_pkg_type response_type,
145         unsigned int timeout_msec)
146 {
147         struct tb_cfg_request *req;
148         struct tb_cfg_result res;
149
150         req = tb_cfg_request_alloc();
151         if (!req)
152                 return -ENOMEM;
153
154         req->match = tb_xdomain_match;
155         req->copy = tb_xdomain_copy;
156         req->request = request;
157         req->request_size = request_size;
158         req->request_type = request_type;
159         req->response = response;
160         req->response_size = response_size;
161         req->response_type = response_type;
162
163         res = tb_cfg_request_sync(ctl, req, timeout_msec);
164
165         tb_cfg_request_put(req);
166
167         return res.err == 1 ? -EIO : res.err;
168 }
169
170 /**
171  * tb_xdomain_request() - Send a XDomain request
172  * @xd: XDomain to send the request
173  * @request: Request to send
174  * @request_size: Size of the request in bytes
175  * @request_type: PDF type of the request
176  * @response: Response is copied here
177  * @response_size: Expected size of the response in bytes
178  * @response_type: Expected PDF type of the response
179  * @timeout_msec: Timeout in milliseconds to wait for the response
180  *
181  * This function can be used to send XDomain control channel messages to
182  * the other domain. The function waits until the response is received
183  * or when timeout triggers. Whichever comes first.
184  *
185  * Return: %0 in case of success and negative errno in case of failure
186  */
187 int tb_xdomain_request(struct tb_xdomain *xd, const void *request,
188         size_t request_size, enum tb_cfg_pkg_type request_type,
189         void *response, size_t response_size,
190         enum tb_cfg_pkg_type response_type, unsigned int timeout_msec)
191 {
192         return __tb_xdomain_request(xd->tb->ctl, request, request_size,
193                                     request_type, response, response_size,
194                                     response_type, timeout_msec);
195 }
196 EXPORT_SYMBOL_GPL(tb_xdomain_request);
197
198 static inline void tb_xdp_fill_header(struct tb_xdp_header *hdr, u64 route,
199         u8 sequence, enum tb_xdp_type type, size_t size)
200 {
201         u32 length_sn;
202
203         length_sn = (size - sizeof(hdr->xd_hdr)) / 4;
204         length_sn |= (sequence << TB_XDOMAIN_SN_SHIFT) & TB_XDOMAIN_SN_MASK;
205
206         hdr->xd_hdr.route_hi = upper_32_bits(route);
207         hdr->xd_hdr.route_lo = lower_32_bits(route);
208         hdr->xd_hdr.length_sn = length_sn;
209         hdr->type = type;
210         memcpy(&hdr->uuid, &tb_xdp_uuid, sizeof(tb_xdp_uuid));
211 }
212
213 static int tb_xdp_handle_error(const struct tb_xdp_header *hdr)
214 {
215         const struct tb_xdp_error_response *error;
216
217         if (hdr->type != ERROR_RESPONSE)
218                 return 0;
219
220         error = (const struct tb_xdp_error_response *)hdr;
221
222         switch (error->error) {
223         case ERROR_UNKNOWN_PACKET:
224         case ERROR_UNKNOWN_DOMAIN:
225                 return -EIO;
226         case ERROR_NOT_SUPPORTED:
227                 return -ENOTSUPP;
228         case ERROR_NOT_READY:
229                 return -EAGAIN;
230         default:
231                 break;
232         }
233
234         return 0;
235 }
236
237 static int tb_xdp_uuid_request(struct tb_ctl *ctl, u64 route, int retry,
238                                uuid_t *uuid)
239 {
240         struct tb_xdp_uuid_response res;
241         struct tb_xdp_uuid req;
242         int ret;
243
244         memset(&req, 0, sizeof(req));
245         tb_xdp_fill_header(&req.hdr, route, retry % 4, UUID_REQUEST,
246                            sizeof(req));
247
248         memset(&res, 0, sizeof(res));
249         ret = __tb_xdomain_request(ctl, &req, sizeof(req),
250                                    TB_CFG_PKG_XDOMAIN_REQ, &res, sizeof(res),
251                                    TB_CFG_PKG_XDOMAIN_RESP,
252                                    XDOMAIN_DEFAULT_TIMEOUT);
253         if (ret)
254                 return ret;
255
256         ret = tb_xdp_handle_error(&res.hdr);
257         if (ret)
258                 return ret;
259
260         uuid_copy(uuid, &res.src_uuid);
261         return 0;
262 }
263
264 static int tb_xdp_uuid_response(struct tb_ctl *ctl, u64 route, u8 sequence,
265                                 const uuid_t *uuid)
266 {
267         struct tb_xdp_uuid_response res;
268
269         memset(&res, 0, sizeof(res));
270         tb_xdp_fill_header(&res.hdr, route, sequence, UUID_RESPONSE,
271                            sizeof(res));
272
273         uuid_copy(&res.src_uuid, uuid);
274         res.src_route_hi = upper_32_bits(route);
275         res.src_route_lo = lower_32_bits(route);
276
277         return __tb_xdomain_response(ctl, &res, sizeof(res),
278                                      TB_CFG_PKG_XDOMAIN_RESP);
279 }
280
281 static int tb_xdp_error_response(struct tb_ctl *ctl, u64 route, u8 sequence,
282                                  enum tb_xdp_error error)
283 {
284         struct tb_xdp_error_response res;
285
286         memset(&res, 0, sizeof(res));
287         tb_xdp_fill_header(&res.hdr, route, sequence, ERROR_RESPONSE,
288                            sizeof(res));
289         res.error = error;
290
291         return __tb_xdomain_response(ctl, &res, sizeof(res),
292                                      TB_CFG_PKG_XDOMAIN_RESP);
293 }
294
295 static int tb_xdp_properties_request(struct tb_ctl *ctl, u64 route,
296         const uuid_t *src_uuid, const uuid_t *dst_uuid, int retry,
297         u32 **block, u32 *generation)
298 {
299         struct tb_xdp_properties_response *res;
300         struct tb_xdp_properties req;
301         u16 data_len, len;
302         size_t total_size;
303         u32 *data = NULL;
304         int ret;
305
306         total_size = sizeof(*res) + TB_XDP_PROPERTIES_MAX_DATA_LENGTH * 4;
307         res = kzalloc(total_size, GFP_KERNEL);
308         if (!res)
309                 return -ENOMEM;
310
311         memset(&req, 0, sizeof(req));
312         tb_xdp_fill_header(&req.hdr, route, retry % 4, PROPERTIES_REQUEST,
313                            sizeof(req));
314         memcpy(&req.src_uuid, src_uuid, sizeof(*src_uuid));
315         memcpy(&req.dst_uuid, dst_uuid, sizeof(*dst_uuid));
316
317         len = 0;
318         data_len = 0;
319
320         do {
321                 ret = __tb_xdomain_request(ctl, &req, sizeof(req),
322                                            TB_CFG_PKG_XDOMAIN_REQ, res,
323                                            total_size, TB_CFG_PKG_XDOMAIN_RESP,
324                                            XDOMAIN_DEFAULT_TIMEOUT);
325                 if (ret)
326                         goto err;
327
328                 ret = tb_xdp_handle_error(&res->hdr);
329                 if (ret)
330                         goto err;
331
332                 /*
333                  * Package length includes the whole payload without the
334                  * XDomain header. Validate first that the package is at
335                  * least size of the response structure.
336                  */
337                 len = res->hdr.xd_hdr.length_sn & TB_XDOMAIN_LENGTH_MASK;
338                 if (len < sizeof(*res) / 4) {
339                         ret = -EINVAL;
340                         goto err;
341                 }
342
343                 len += sizeof(res->hdr.xd_hdr) / 4;
344                 len -= sizeof(*res) / 4;
345
346                 if (res->offset != req.offset) {
347                         ret = -EINVAL;
348                         goto err;
349                 }
350
351                 /*
352                  * First time allocate block that has enough space for
353                  * the whole properties block.
354                  */
355                 if (!data) {
356                         data_len = res->data_length;
357                         if (data_len > TB_XDP_PROPERTIES_MAX_LENGTH) {
358                                 ret = -E2BIG;
359                                 goto err;
360                         }
361
362                         data = kcalloc(data_len, sizeof(u32), GFP_KERNEL);
363                         if (!data) {
364                                 ret = -ENOMEM;
365                                 goto err;
366                         }
367                 }
368
369                 memcpy(data + req.offset, res->data, len * 4);
370                 req.offset += len;
371         } while (!data_len || req.offset < data_len);
372
373         *block = data;
374         *generation = res->generation;
375
376         kfree(res);
377
378         return data_len;
379
380 err:
381         kfree(data);
382         kfree(res);
383
384         return ret;
385 }
386
387 static int tb_xdp_properties_response(struct tb *tb, struct tb_ctl *ctl,
388         u64 route, u8 sequence, const uuid_t *src_uuid,
389         const struct tb_xdp_properties *req)
390 {
391         struct tb_xdp_properties_response *res;
392         size_t total_size;
393         u16 len;
394         int ret;
395
396         /*
397          * Currently we expect all requests to be directed to us. The
398          * protocol supports forwarding, though which we might add
399          * support later on.
400          */
401         if (!uuid_equal(src_uuid, &req->dst_uuid)) {
402                 tb_xdp_error_response(ctl, route, sequence,
403                                       ERROR_UNKNOWN_DOMAIN);
404                 return 0;
405         }
406
407         mutex_lock(&xdomain_lock);
408
409         if (req->offset >= xdomain_property_block_len) {
410                 mutex_unlock(&xdomain_lock);
411                 return -EINVAL;
412         }
413
414         len = xdomain_property_block_len - req->offset;
415         len = min_t(u16, len, TB_XDP_PROPERTIES_MAX_DATA_LENGTH);
416         total_size = sizeof(*res) + len * 4;
417
418         res = kzalloc(total_size, GFP_KERNEL);
419         if (!res) {
420                 mutex_unlock(&xdomain_lock);
421                 return -ENOMEM;
422         }
423
424         tb_xdp_fill_header(&res->hdr, route, sequence, PROPERTIES_RESPONSE,
425                            total_size);
426         res->generation = xdomain_property_block_gen;
427         res->data_length = xdomain_property_block_len;
428         res->offset = req->offset;
429         uuid_copy(&res->src_uuid, src_uuid);
430         uuid_copy(&res->dst_uuid, &req->src_uuid);
431         memcpy(res->data, &xdomain_property_block[req->offset], len * 4);
432
433         mutex_unlock(&xdomain_lock);
434
435         ret = __tb_xdomain_response(ctl, res, total_size,
436                                     TB_CFG_PKG_XDOMAIN_RESP);
437
438         kfree(res);
439         return ret;
440 }
441
442 static int tb_xdp_properties_changed_request(struct tb_ctl *ctl, u64 route,
443                                              int retry, const uuid_t *uuid)
444 {
445         struct tb_xdp_properties_changed_response res;
446         struct tb_xdp_properties_changed req;
447         int ret;
448
449         memset(&req, 0, sizeof(req));
450         tb_xdp_fill_header(&req.hdr, route, retry % 4,
451                            PROPERTIES_CHANGED_REQUEST, sizeof(req));
452         uuid_copy(&req.src_uuid, uuid);
453
454         memset(&res, 0, sizeof(res));
455         ret = __tb_xdomain_request(ctl, &req, sizeof(req),
456                                    TB_CFG_PKG_XDOMAIN_REQ, &res, sizeof(res),
457                                    TB_CFG_PKG_XDOMAIN_RESP,
458                                    XDOMAIN_DEFAULT_TIMEOUT);
459         if (ret)
460                 return ret;
461
462         return tb_xdp_handle_error(&res.hdr);
463 }
464
465 static int
466 tb_xdp_properties_changed_response(struct tb_ctl *ctl, u64 route, u8 sequence)
467 {
468         struct tb_xdp_properties_changed_response res;
469
470         memset(&res, 0, sizeof(res));
471         tb_xdp_fill_header(&res.hdr, route, sequence,
472                            PROPERTIES_CHANGED_RESPONSE, sizeof(res));
473         return __tb_xdomain_response(ctl, &res, sizeof(res),
474                                      TB_CFG_PKG_XDOMAIN_RESP);
475 }
476
477 /**
478  * tb_register_protocol_handler() - Register protocol handler
479  * @handler: Handler to register
480  *
481  * This allows XDomain service drivers to hook into incoming XDomain
482  * messages. After this function is called the service driver needs to
483  * be able to handle calls to callback whenever a package with the
484  * registered protocol is received.
485  */
486 int tb_register_protocol_handler(struct tb_protocol_handler *handler)
487 {
488         if (!handler->uuid || !handler->callback)
489                 return -EINVAL;
490         if (uuid_equal(handler->uuid, &tb_xdp_uuid))
491                 return -EINVAL;
492
493         mutex_lock(&xdomain_lock);
494         list_add_tail(&handler->list, &protocol_handlers);
495         mutex_unlock(&xdomain_lock);
496
497         return 0;
498 }
499 EXPORT_SYMBOL_GPL(tb_register_protocol_handler);
500
501 /**
502  * tb_unregister_protocol_handler() - Unregister protocol handler
503  * @handler: Handler to unregister
504  *
505  * Removes the previously registered protocol handler.
506  */
507 void tb_unregister_protocol_handler(struct tb_protocol_handler *handler)
508 {
509         mutex_lock(&xdomain_lock);
510         list_del_init(&handler->list);
511         mutex_unlock(&xdomain_lock);
512 }
513 EXPORT_SYMBOL_GPL(tb_unregister_protocol_handler);
514
515 static int rebuild_property_block(void)
516 {
517         u32 *block, len;
518         int ret;
519
520         ret = tb_property_format_dir(xdomain_property_dir, NULL, 0);
521         if (ret < 0)
522                 return ret;
523
524         len = ret;
525
526         block = kcalloc(len, sizeof(u32), GFP_KERNEL);
527         if (!block)
528                 return -ENOMEM;
529
530         ret = tb_property_format_dir(xdomain_property_dir, block, len);
531         if (ret) {
532                 kfree(block);
533                 return ret;
534         }
535
536         kfree(xdomain_property_block);
537         xdomain_property_block = block;
538         xdomain_property_block_len = len;
539         xdomain_property_block_gen++;
540
541         return 0;
542 }
543
544 static void finalize_property_block(void)
545 {
546         const struct tb_property *nodename;
547
548         /*
549          * On first XDomain connection we set up the the system
550          * nodename. This delayed here because userspace may not have it
551          * set when the driver is first probed.
552          */
553         mutex_lock(&xdomain_lock);
554         nodename = tb_property_find(xdomain_property_dir, "deviceid",
555                                     TB_PROPERTY_TYPE_TEXT);
556         if (!nodename) {
557                 tb_property_add_text(xdomain_property_dir, "deviceid",
558                                      utsname()->nodename);
559                 rebuild_property_block();
560         }
561         mutex_unlock(&xdomain_lock);
562 }
563
564 static void tb_xdp_handle_request(struct work_struct *work)
565 {
566         struct xdomain_request_work *xw = container_of(work, typeof(*xw), work);
567         const struct tb_xdp_header *pkg = xw->pkg;
568         const struct tb_xdomain_header *xhdr = &pkg->xd_hdr;
569         struct tb *tb = xw->tb;
570         struct tb_ctl *ctl = tb->ctl;
571         const uuid_t *uuid;
572         int ret = 0;
573         u32 sequence;
574         u64 route;
575
576         route = ((u64)xhdr->route_hi << 32 | xhdr->route_lo) & ~BIT_ULL(63);
577         sequence = xhdr->length_sn & TB_XDOMAIN_SN_MASK;
578         sequence >>= TB_XDOMAIN_SN_SHIFT;
579
580         mutex_lock(&tb->lock);
581         if (tb->root_switch)
582                 uuid = tb->root_switch->uuid;
583         else
584                 uuid = NULL;
585         mutex_unlock(&tb->lock);
586
587         if (!uuid) {
588                 tb_xdp_error_response(ctl, route, sequence, ERROR_NOT_READY);
589                 goto out;
590         }
591
592         finalize_property_block();
593
594         switch (pkg->type) {
595         case PROPERTIES_REQUEST:
596                 ret = tb_xdp_properties_response(tb, ctl, route, sequence, uuid,
597                         (const struct tb_xdp_properties *)pkg);
598                 break;
599
600         case PROPERTIES_CHANGED_REQUEST: {
601                 struct tb_xdomain *xd;
602
603                 ret = tb_xdp_properties_changed_response(ctl, route, sequence);
604
605                 /*
606                  * Since the properties have been changed, let's update
607                  * the xdomain related to this connection as well in
608                  * case there is a change in services it offers.
609                  */
610                 xd = tb_xdomain_find_by_route_locked(tb, route);
611                 if (xd) {
612                         if (device_is_registered(&xd->dev)) {
613                                 queue_delayed_work(tb->wq, &xd->get_properties_work,
614                                                    msecs_to_jiffies(50));
615                         }
616                         tb_xdomain_put(xd);
617                 }
618
619                 break;
620         }
621
622         case UUID_REQUEST_OLD:
623         case UUID_REQUEST:
624                 ret = tb_xdp_uuid_response(ctl, route, sequence, uuid);
625                 break;
626
627         default:
628                 tb_xdp_error_response(ctl, route, sequence,
629                                       ERROR_NOT_SUPPORTED);
630                 break;
631         }
632
633         if (ret) {
634                 tb_warn(tb, "failed to send XDomain response for %#x\n",
635                         pkg->type);
636         }
637
638 out:
639         kfree(xw->pkg);
640         kfree(xw);
641
642         tb_domain_put(tb);
643 }
644
645 static bool
646 tb_xdp_schedule_request(struct tb *tb, const struct tb_xdp_header *hdr,
647                         size_t size)
648 {
649         struct xdomain_request_work *xw;
650
651         xw = kmalloc(sizeof(*xw), GFP_KERNEL);
652         if (!xw)
653                 return false;
654
655         INIT_WORK(&xw->work, tb_xdp_handle_request);
656         xw->pkg = kmemdup(hdr, size, GFP_KERNEL);
657         if (!xw->pkg) {
658                 kfree(xw);
659                 return false;
660         }
661         xw->tb = tb_domain_get(tb);
662
663         schedule_work(&xw->work);
664         return true;
665 }
666
667 /**
668  * tb_register_service_driver() - Register XDomain service driver
669  * @drv: Driver to register
670  *
671  * Registers new service driver from @drv to the bus.
672  */
673 int tb_register_service_driver(struct tb_service_driver *drv)
674 {
675         drv->driver.bus = &tb_bus_type;
676         return driver_register(&drv->driver);
677 }
678 EXPORT_SYMBOL_GPL(tb_register_service_driver);
679
680 /**
681  * tb_unregister_service_driver() - Unregister XDomain service driver
682  * @drv: Driver to unregister
683  *
684  * Unregisters XDomain service driver from the bus.
685  */
686 void tb_unregister_service_driver(struct tb_service_driver *drv)
687 {
688         driver_unregister(&drv->driver);
689 }
690 EXPORT_SYMBOL_GPL(tb_unregister_service_driver);
691
692 static ssize_t key_show(struct device *dev, struct device_attribute *attr,
693                         char *buf)
694 {
695         struct tb_service *svc = container_of(dev, struct tb_service, dev);
696
697         /*
698          * It should be null terminated but anything else is pretty much
699          * allowed.
700          */
701         return sprintf(buf, "%*pE\n", (int)strlen(svc->key), svc->key);
702 }
703 static DEVICE_ATTR_RO(key);
704
705 static int get_modalias(struct tb_service *svc, char *buf, size_t size)
706 {
707         return snprintf(buf, size, "tbsvc:k%sp%08Xv%08Xr%08X", svc->key,
708                         svc->prtcid, svc->prtcvers, svc->prtcrevs);
709 }
710
711 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
712                              char *buf)
713 {
714         struct tb_service *svc = container_of(dev, struct tb_service, dev);
715
716         /* Full buffer size except new line and null termination */
717         get_modalias(svc, buf, PAGE_SIZE - 2);
718         return sprintf(buf, "%s\n", buf);
719 }
720 static DEVICE_ATTR_RO(modalias);
721
722 static ssize_t prtcid_show(struct device *dev, struct device_attribute *attr,
723                            char *buf)
724 {
725         struct tb_service *svc = container_of(dev, struct tb_service, dev);
726
727         return sprintf(buf, "%u\n", svc->prtcid);
728 }
729 static DEVICE_ATTR_RO(prtcid);
730
731 static ssize_t prtcvers_show(struct device *dev, struct device_attribute *attr,
732                              char *buf)
733 {
734         struct tb_service *svc = container_of(dev, struct tb_service, dev);
735
736         return sprintf(buf, "%u\n", svc->prtcvers);
737 }
738 static DEVICE_ATTR_RO(prtcvers);
739
740 static ssize_t prtcrevs_show(struct device *dev, struct device_attribute *attr,
741                              char *buf)
742 {
743         struct tb_service *svc = container_of(dev, struct tb_service, dev);
744
745         return sprintf(buf, "%u\n", svc->prtcrevs);
746 }
747 static DEVICE_ATTR_RO(prtcrevs);
748
749 static ssize_t prtcstns_show(struct device *dev, struct device_attribute *attr,
750                              char *buf)
751 {
752         struct tb_service *svc = container_of(dev, struct tb_service, dev);
753
754         return sprintf(buf, "0x%08x\n", svc->prtcstns);
755 }
756 static DEVICE_ATTR_RO(prtcstns);
757
758 static struct attribute *tb_service_attrs[] = {
759         &dev_attr_key.attr,
760         &dev_attr_modalias.attr,
761         &dev_attr_prtcid.attr,
762         &dev_attr_prtcvers.attr,
763         &dev_attr_prtcrevs.attr,
764         &dev_attr_prtcstns.attr,
765         NULL,
766 };
767
768 static const struct attribute_group tb_service_attr_group = {
769         .attrs = tb_service_attrs,
770 };
771
772 static const struct attribute_group *tb_service_attr_groups[] = {
773         &tb_service_attr_group,
774         NULL,
775 };
776
777 static int tb_service_uevent(struct device *dev, struct kobj_uevent_env *env)
778 {
779         struct tb_service *svc = container_of(dev, struct tb_service, dev);
780         char modalias[64];
781
782         get_modalias(svc, modalias, sizeof(modalias));
783         return add_uevent_var(env, "MODALIAS=%s", modalias);
784 }
785
786 static void tb_service_release(struct device *dev)
787 {
788         struct tb_service *svc = container_of(dev, struct tb_service, dev);
789         struct tb_xdomain *xd = tb_service_parent(svc);
790
791         tb_service_debugfs_remove(svc);
792         ida_simple_remove(&xd->service_ids, svc->id);
793         kfree(svc->key);
794         kfree(svc);
795 }
796
797 struct device_type tb_service_type = {
798         .name = "thunderbolt_service",
799         .groups = tb_service_attr_groups,
800         .uevent = tb_service_uevent,
801         .release = tb_service_release,
802 };
803 EXPORT_SYMBOL_GPL(tb_service_type);
804
805 static int remove_missing_service(struct device *dev, void *data)
806 {
807         struct tb_xdomain *xd = data;
808         struct tb_service *svc;
809
810         svc = tb_to_service(dev);
811         if (!svc)
812                 return 0;
813
814         if (!tb_property_find(xd->properties, svc->key,
815                               TB_PROPERTY_TYPE_DIRECTORY))
816                 device_unregister(dev);
817
818         return 0;
819 }
820
821 static int find_service(struct device *dev, void *data)
822 {
823         const struct tb_property *p = data;
824         struct tb_service *svc;
825
826         svc = tb_to_service(dev);
827         if (!svc)
828                 return 0;
829
830         return !strcmp(svc->key, p->key);
831 }
832
833 static int populate_service(struct tb_service *svc,
834                             struct tb_property *property)
835 {
836         struct tb_property_dir *dir = property->value.dir;
837         struct tb_property *p;
838
839         /* Fill in standard properties */
840         p = tb_property_find(dir, "prtcid", TB_PROPERTY_TYPE_VALUE);
841         if (p)
842                 svc->prtcid = p->value.immediate;
843         p = tb_property_find(dir, "prtcvers", TB_PROPERTY_TYPE_VALUE);
844         if (p)
845                 svc->prtcvers = p->value.immediate;
846         p = tb_property_find(dir, "prtcrevs", TB_PROPERTY_TYPE_VALUE);
847         if (p)
848                 svc->prtcrevs = p->value.immediate;
849         p = tb_property_find(dir, "prtcstns", TB_PROPERTY_TYPE_VALUE);
850         if (p)
851                 svc->prtcstns = p->value.immediate;
852
853         svc->key = kstrdup(property->key, GFP_KERNEL);
854         if (!svc->key)
855                 return -ENOMEM;
856
857         return 0;
858 }
859
860 static void enumerate_services(struct tb_xdomain *xd)
861 {
862         struct tb_service *svc;
863         struct tb_property *p;
864         struct device *dev;
865         int id;
866
867         /*
868          * First remove all services that are not available anymore in
869          * the updated property block.
870          */
871         device_for_each_child_reverse(&xd->dev, xd, remove_missing_service);
872
873         /* Then re-enumerate properties creating new services as we go */
874         tb_property_for_each(xd->properties, p) {
875                 if (p->type != TB_PROPERTY_TYPE_DIRECTORY)
876                         continue;
877
878                 /* If the service exists already we are fine */
879                 dev = device_find_child(&xd->dev, p, find_service);
880                 if (dev) {
881                         put_device(dev);
882                         continue;
883                 }
884
885                 svc = kzalloc(sizeof(*svc), GFP_KERNEL);
886                 if (!svc)
887                         break;
888
889                 if (populate_service(svc, p)) {
890                         kfree(svc);
891                         break;
892                 }
893
894                 id = ida_simple_get(&xd->service_ids, 0, 0, GFP_KERNEL);
895                 if (id < 0) {
896                         kfree(svc->key);
897                         kfree(svc);
898                         break;
899                 }
900                 svc->id = id;
901                 svc->dev.bus = &tb_bus_type;
902                 svc->dev.type = &tb_service_type;
903                 svc->dev.parent = &xd->dev;
904                 dev_set_name(&svc->dev, "%s.%d", dev_name(&xd->dev), svc->id);
905
906                 tb_service_debugfs_init(svc);
907
908                 if (device_register(&svc->dev)) {
909                         put_device(&svc->dev);
910                         break;
911                 }
912         }
913 }
914
915 static int populate_properties(struct tb_xdomain *xd,
916                                struct tb_property_dir *dir)
917 {
918         const struct tb_property *p;
919
920         /* Required properties */
921         p = tb_property_find(dir, "deviceid", TB_PROPERTY_TYPE_VALUE);
922         if (!p)
923                 return -EINVAL;
924         xd->device = p->value.immediate;
925
926         p = tb_property_find(dir, "vendorid", TB_PROPERTY_TYPE_VALUE);
927         if (!p)
928                 return -EINVAL;
929         xd->vendor = p->value.immediate;
930
931         kfree(xd->device_name);
932         xd->device_name = NULL;
933         kfree(xd->vendor_name);
934         xd->vendor_name = NULL;
935
936         /* Optional properties */
937         p = tb_property_find(dir, "deviceid", TB_PROPERTY_TYPE_TEXT);
938         if (p)
939                 xd->device_name = kstrdup(p->value.text, GFP_KERNEL);
940         p = tb_property_find(dir, "vendorid", TB_PROPERTY_TYPE_TEXT);
941         if (p)
942                 xd->vendor_name = kstrdup(p->value.text, GFP_KERNEL);
943
944         return 0;
945 }
946
947 /* Called with @xd->lock held */
948 static void tb_xdomain_restore_paths(struct tb_xdomain *xd)
949 {
950         if (!xd->resume)
951                 return;
952
953         xd->resume = false;
954         if (xd->transmit_path) {
955                 dev_dbg(&xd->dev, "re-establishing DMA path\n");
956                 tb_domain_approve_xdomain_paths(xd->tb, xd);
957         }
958 }
959
960 static inline struct tb_switch *tb_xdomain_parent(struct tb_xdomain *xd)
961 {
962         return tb_to_switch(xd->dev.parent);
963 }
964
965 static int tb_xdomain_update_link_attributes(struct tb_xdomain *xd)
966 {
967         bool change = false;
968         struct tb_port *port;
969         int ret;
970
971         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
972
973         ret = tb_port_get_link_speed(port);
974         if (ret < 0)
975                 return ret;
976
977         if (xd->link_speed != ret)
978                 change = true;
979
980         xd->link_speed = ret;
981
982         ret = tb_port_get_link_width(port);
983         if (ret < 0)
984                 return ret;
985
986         if (xd->link_width != ret)
987                 change = true;
988
989         xd->link_width = ret;
990
991         if (change)
992                 kobject_uevent(&xd->dev.kobj, KOBJ_CHANGE);
993
994         return 0;
995 }
996
997 static void tb_xdomain_get_uuid(struct work_struct *work)
998 {
999         struct tb_xdomain *xd = container_of(work, typeof(*xd),
1000                                              get_uuid_work.work);
1001         struct tb *tb = xd->tb;
1002         uuid_t uuid;
1003         int ret;
1004
1005         ret = tb_xdp_uuid_request(tb->ctl, xd->route, xd->uuid_retries, &uuid);
1006         if (ret < 0) {
1007                 if (xd->uuid_retries-- > 0) {
1008                         queue_delayed_work(xd->tb->wq, &xd->get_uuid_work,
1009                                            msecs_to_jiffies(100));
1010                 } else {
1011                         dev_dbg(&xd->dev, "failed to read remote UUID\n");
1012                 }
1013                 return;
1014         }
1015
1016         if (uuid_equal(&uuid, xd->local_uuid))
1017                 dev_dbg(&xd->dev, "intra-domain loop detected\n");
1018
1019         /*
1020          * If the UUID is different, there is another domain connected
1021          * so mark this one unplugged and wait for the connection
1022          * manager to replace it.
1023          */
1024         if (xd->remote_uuid && !uuid_equal(&uuid, xd->remote_uuid)) {
1025                 dev_dbg(&xd->dev, "remote UUID is different, unplugging\n");
1026                 xd->is_unplugged = true;
1027                 return;
1028         }
1029
1030         /* First time fill in the missing UUID */
1031         if (!xd->remote_uuid) {
1032                 xd->remote_uuid = kmemdup(&uuid, sizeof(uuid_t), GFP_KERNEL);
1033                 if (!xd->remote_uuid)
1034                         return;
1035         }
1036
1037         /* Now we can start the normal properties exchange */
1038         queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
1039                            msecs_to_jiffies(100));
1040         queue_delayed_work(xd->tb->wq, &xd->get_properties_work,
1041                            msecs_to_jiffies(1000));
1042 }
1043
1044 static void tb_xdomain_get_properties(struct work_struct *work)
1045 {
1046         struct tb_xdomain *xd = container_of(work, typeof(*xd),
1047                                              get_properties_work.work);
1048         struct tb_property_dir *dir;
1049         struct tb *tb = xd->tb;
1050         bool update = false;
1051         u32 *block = NULL;
1052         u32 gen = 0;
1053         int ret;
1054
1055         ret = tb_xdp_properties_request(tb->ctl, xd->route, xd->local_uuid,
1056                                         xd->remote_uuid, xd->properties_retries,
1057                                         &block, &gen);
1058         if (ret < 0) {
1059                 if (xd->properties_retries-- > 0) {
1060                         queue_delayed_work(xd->tb->wq, &xd->get_properties_work,
1061                                            msecs_to_jiffies(1000));
1062                 } else {
1063                         /* Give up now */
1064                         dev_err(&xd->dev,
1065                                 "failed read XDomain properties from %pUb\n",
1066                                 xd->remote_uuid);
1067                 }
1068                 return;
1069         }
1070
1071         xd->properties_retries = XDOMAIN_PROPERTIES_RETRIES;
1072
1073         mutex_lock(&xd->lock);
1074
1075         /* Only accept newer generation properties */
1076         if (xd->properties && gen <= xd->property_block_gen) {
1077                 /*
1078                  * On resume it is likely that the properties block is
1079                  * not changed (unless the other end added or removed
1080                  * services). However, we need to make sure the existing
1081                  * DMA paths are restored properly.
1082                  */
1083                 tb_xdomain_restore_paths(xd);
1084                 goto err_free_block;
1085         }
1086
1087         dir = tb_property_parse_dir(block, ret);
1088         if (!dir) {
1089                 dev_err(&xd->dev, "failed to parse XDomain properties\n");
1090                 goto err_free_block;
1091         }
1092
1093         ret = populate_properties(xd, dir);
1094         if (ret) {
1095                 dev_err(&xd->dev, "missing XDomain properties in response\n");
1096                 goto err_free_dir;
1097         }
1098
1099         /* Release the existing one */
1100         if (xd->properties) {
1101                 tb_property_free_dir(xd->properties);
1102                 update = true;
1103         }
1104
1105         xd->properties = dir;
1106         xd->property_block_gen = gen;
1107
1108         tb_xdomain_update_link_attributes(xd);
1109
1110         tb_xdomain_restore_paths(xd);
1111
1112         mutex_unlock(&xd->lock);
1113
1114         kfree(block);
1115
1116         /*
1117          * Now the device should be ready enough so we can add it to the
1118          * bus and let userspace know about it. If the device is already
1119          * registered, we notify the userspace that it has changed.
1120          */
1121         if (!update) {
1122                 if (device_add(&xd->dev)) {
1123                         dev_err(&xd->dev, "failed to add XDomain device\n");
1124                         return;
1125                 }
1126         } else {
1127                 kobject_uevent(&xd->dev.kobj, KOBJ_CHANGE);
1128         }
1129
1130         enumerate_services(xd);
1131         return;
1132
1133 err_free_dir:
1134         tb_property_free_dir(dir);
1135 err_free_block:
1136         kfree(block);
1137         mutex_unlock(&xd->lock);
1138 }
1139
1140 static void tb_xdomain_properties_changed(struct work_struct *work)
1141 {
1142         struct tb_xdomain *xd = container_of(work, typeof(*xd),
1143                                              properties_changed_work.work);
1144         int ret;
1145
1146         ret = tb_xdp_properties_changed_request(xd->tb->ctl, xd->route,
1147                                 xd->properties_changed_retries, xd->local_uuid);
1148         if (ret) {
1149                 if (xd->properties_changed_retries-- > 0)
1150                         queue_delayed_work(xd->tb->wq,
1151                                            &xd->properties_changed_work,
1152                                            msecs_to_jiffies(1000));
1153                 return;
1154         }
1155
1156         xd->properties_changed_retries = XDOMAIN_PROPERTIES_CHANGED_RETRIES;
1157 }
1158
1159 static ssize_t device_show(struct device *dev, struct device_attribute *attr,
1160                            char *buf)
1161 {
1162         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1163
1164         return sprintf(buf, "%#x\n", xd->device);
1165 }
1166 static DEVICE_ATTR_RO(device);
1167
1168 static ssize_t
1169 device_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1170 {
1171         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1172         int ret;
1173
1174         if (mutex_lock_interruptible(&xd->lock))
1175                 return -ERESTARTSYS;
1176         ret = sprintf(buf, "%s\n", xd->device_name ? xd->device_name : "");
1177         mutex_unlock(&xd->lock);
1178
1179         return ret;
1180 }
1181 static DEVICE_ATTR_RO(device_name);
1182
1183 static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
1184                            char *buf)
1185 {
1186         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1187
1188         return sprintf(buf, "%#x\n", xd->vendor);
1189 }
1190 static DEVICE_ATTR_RO(vendor);
1191
1192 static ssize_t
1193 vendor_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1194 {
1195         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1196         int ret;
1197
1198         if (mutex_lock_interruptible(&xd->lock))
1199                 return -ERESTARTSYS;
1200         ret = sprintf(buf, "%s\n", xd->vendor_name ? xd->vendor_name : "");
1201         mutex_unlock(&xd->lock);
1202
1203         return ret;
1204 }
1205 static DEVICE_ATTR_RO(vendor_name);
1206
1207 static ssize_t unique_id_show(struct device *dev, struct device_attribute *attr,
1208                               char *buf)
1209 {
1210         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1211
1212         return sprintf(buf, "%pUb\n", xd->remote_uuid);
1213 }
1214 static DEVICE_ATTR_RO(unique_id);
1215
1216 static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
1217                           char *buf)
1218 {
1219         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1220
1221         return sprintf(buf, "%u.0 Gb/s\n", xd->link_speed);
1222 }
1223
1224 static DEVICE_ATTR(rx_speed, 0444, speed_show, NULL);
1225 static DEVICE_ATTR(tx_speed, 0444, speed_show, NULL);
1226
1227 static ssize_t lanes_show(struct device *dev, struct device_attribute *attr,
1228                           char *buf)
1229 {
1230         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1231
1232         return sprintf(buf, "%u\n", xd->link_width);
1233 }
1234
1235 static DEVICE_ATTR(rx_lanes, 0444, lanes_show, NULL);
1236 static DEVICE_ATTR(tx_lanes, 0444, lanes_show, NULL);
1237
1238 static struct attribute *xdomain_attrs[] = {
1239         &dev_attr_device.attr,
1240         &dev_attr_device_name.attr,
1241         &dev_attr_rx_lanes.attr,
1242         &dev_attr_rx_speed.attr,
1243         &dev_attr_tx_lanes.attr,
1244         &dev_attr_tx_speed.attr,
1245         &dev_attr_unique_id.attr,
1246         &dev_attr_vendor.attr,
1247         &dev_attr_vendor_name.attr,
1248         NULL,
1249 };
1250
1251 static const struct attribute_group xdomain_attr_group = {
1252         .attrs = xdomain_attrs,
1253 };
1254
1255 static const struct attribute_group *xdomain_attr_groups[] = {
1256         &xdomain_attr_group,
1257         NULL,
1258 };
1259
1260 static void tb_xdomain_release(struct device *dev)
1261 {
1262         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1263
1264         put_device(xd->dev.parent);
1265
1266         tb_property_free_dir(xd->properties);
1267         ida_destroy(&xd->service_ids);
1268
1269         kfree(xd->local_uuid);
1270         kfree(xd->remote_uuid);
1271         kfree(xd->device_name);
1272         kfree(xd->vendor_name);
1273         kfree(xd);
1274 }
1275
1276 static void start_handshake(struct tb_xdomain *xd)
1277 {
1278         xd->uuid_retries = XDOMAIN_UUID_RETRIES;
1279         xd->properties_retries = XDOMAIN_PROPERTIES_RETRIES;
1280         xd->properties_changed_retries = XDOMAIN_PROPERTIES_CHANGED_RETRIES;
1281
1282         if (xd->needs_uuid) {
1283                 queue_delayed_work(xd->tb->wq, &xd->get_uuid_work,
1284                                    msecs_to_jiffies(100));
1285         } else {
1286                 /* Start exchanging properties with the other host */
1287                 queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
1288                                    msecs_to_jiffies(100));
1289                 queue_delayed_work(xd->tb->wq, &xd->get_properties_work,
1290                                    msecs_to_jiffies(1000));
1291         }
1292 }
1293
1294 static void stop_handshake(struct tb_xdomain *xd)
1295 {
1296         xd->uuid_retries = 0;
1297         xd->properties_retries = 0;
1298         xd->properties_changed_retries = 0;
1299
1300         cancel_delayed_work_sync(&xd->get_uuid_work);
1301         cancel_delayed_work_sync(&xd->get_properties_work);
1302         cancel_delayed_work_sync(&xd->properties_changed_work);
1303 }
1304
1305 static int __maybe_unused tb_xdomain_suspend(struct device *dev)
1306 {
1307         stop_handshake(tb_to_xdomain(dev));
1308         return 0;
1309 }
1310
1311 static int __maybe_unused tb_xdomain_resume(struct device *dev)
1312 {
1313         struct tb_xdomain *xd = tb_to_xdomain(dev);
1314
1315         /*
1316          * Ask tb_xdomain_get_properties() restore any existing DMA
1317          * paths after properties are re-read.
1318          */
1319         xd->resume = true;
1320         start_handshake(xd);
1321
1322         return 0;
1323 }
1324
1325 static const struct dev_pm_ops tb_xdomain_pm_ops = {
1326         SET_SYSTEM_SLEEP_PM_OPS(tb_xdomain_suspend, tb_xdomain_resume)
1327 };
1328
1329 struct device_type tb_xdomain_type = {
1330         .name = "thunderbolt_xdomain",
1331         .release = tb_xdomain_release,
1332         .pm = &tb_xdomain_pm_ops,
1333 };
1334 EXPORT_SYMBOL_GPL(tb_xdomain_type);
1335
1336 /**
1337  * tb_xdomain_alloc() - Allocate new XDomain object
1338  * @tb: Domain where the XDomain belongs
1339  * @parent: Parent device (the switch through the connection to the
1340  *          other domain is reached).
1341  * @route: Route string used to reach the other domain
1342  * @local_uuid: Our local domain UUID
1343  * @remote_uuid: UUID of the other domain (optional)
1344  *
1345  * Allocates new XDomain structure and returns pointer to that. The
1346  * object must be released by calling tb_xdomain_put().
1347  */
1348 struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent,
1349                                     u64 route, const uuid_t *local_uuid,
1350                                     const uuid_t *remote_uuid)
1351 {
1352         struct tb_switch *parent_sw = tb_to_switch(parent);
1353         struct tb_xdomain *xd;
1354         struct tb_port *down;
1355
1356         /* Make sure the downstream domain is accessible */
1357         down = tb_port_at(route, parent_sw);
1358         tb_port_unlock(down);
1359
1360         xd = kzalloc(sizeof(*xd), GFP_KERNEL);
1361         if (!xd)
1362                 return NULL;
1363
1364         xd->tb = tb;
1365         xd->route = route;
1366         ida_init(&xd->service_ids);
1367         mutex_init(&xd->lock);
1368         INIT_DELAYED_WORK(&xd->get_uuid_work, tb_xdomain_get_uuid);
1369         INIT_DELAYED_WORK(&xd->get_properties_work, tb_xdomain_get_properties);
1370         INIT_DELAYED_WORK(&xd->properties_changed_work,
1371                           tb_xdomain_properties_changed);
1372
1373         xd->local_uuid = kmemdup(local_uuid, sizeof(uuid_t), GFP_KERNEL);
1374         if (!xd->local_uuid)
1375                 goto err_free;
1376
1377         if (remote_uuid) {
1378                 xd->remote_uuid = kmemdup(remote_uuid, sizeof(uuid_t),
1379                                           GFP_KERNEL);
1380                 if (!xd->remote_uuid)
1381                         goto err_free_local_uuid;
1382         } else {
1383                 xd->needs_uuid = true;
1384         }
1385
1386         device_initialize(&xd->dev);
1387         xd->dev.parent = get_device(parent);
1388         xd->dev.bus = &tb_bus_type;
1389         xd->dev.type = &tb_xdomain_type;
1390         xd->dev.groups = xdomain_attr_groups;
1391         dev_set_name(&xd->dev, "%u-%llx", tb->index, route);
1392
1393         /*
1394          * This keeps the DMA powered on as long as we have active
1395          * connection to another host.
1396          */
1397         pm_runtime_set_active(&xd->dev);
1398         pm_runtime_get_noresume(&xd->dev);
1399         pm_runtime_enable(&xd->dev);
1400
1401         return xd;
1402
1403 err_free_local_uuid:
1404         kfree(xd->local_uuid);
1405 err_free:
1406         kfree(xd);
1407
1408         return NULL;
1409 }
1410
1411 /**
1412  * tb_xdomain_add() - Add XDomain to the bus
1413  * @xd: XDomain to add
1414  *
1415  * This function starts XDomain discovery protocol handshake and
1416  * eventually adds the XDomain to the bus. After calling this function
1417  * the caller needs to call tb_xdomain_remove() in order to remove and
1418  * release the object regardless whether the handshake succeeded or not.
1419  */
1420 void tb_xdomain_add(struct tb_xdomain *xd)
1421 {
1422         /* Start exchanging properties with the other host */
1423         start_handshake(xd);
1424 }
1425
1426 static int unregister_service(struct device *dev, void *data)
1427 {
1428         device_unregister(dev);
1429         return 0;
1430 }
1431
1432 /**
1433  * tb_xdomain_remove() - Remove XDomain from the bus
1434  * @xd: XDomain to remove
1435  *
1436  * This will stop all ongoing configuration work and remove the XDomain
1437  * along with any services from the bus. When the last reference to @xd
1438  * is released the object will be released as well.
1439  */
1440 void tb_xdomain_remove(struct tb_xdomain *xd)
1441 {
1442         stop_handshake(xd);
1443
1444         device_for_each_child_reverse(&xd->dev, xd, unregister_service);
1445
1446         /*
1447          * Undo runtime PM here explicitly because it is possible that
1448          * the XDomain was never added to the bus and thus device_del()
1449          * is not called for it (device_del() would handle this otherwise).
1450          */
1451         pm_runtime_disable(&xd->dev);
1452         pm_runtime_put_noidle(&xd->dev);
1453         pm_runtime_set_suspended(&xd->dev);
1454
1455         if (!device_is_registered(&xd->dev))
1456                 put_device(&xd->dev);
1457         else
1458                 device_unregister(&xd->dev);
1459 }
1460
1461 /**
1462  * tb_xdomain_lane_bonding_enable() - Enable lane bonding on XDomain
1463  * @xd: XDomain connection
1464  *
1465  * Lane bonding is disabled by default for XDomains. This function tries
1466  * to enable bonding by first enabling the port and waiting for the CL0
1467  * state.
1468  *
1469  * Return: %0 in case of success and negative errno in case of error.
1470  */
1471 int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd)
1472 {
1473         struct tb_port *port;
1474         int ret;
1475
1476         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1477         if (!port->dual_link_port)
1478                 return -ENODEV;
1479
1480         ret = tb_port_enable(port->dual_link_port);
1481         if (ret)
1482                 return ret;
1483
1484         ret = tb_wait_for_port(port->dual_link_port, true);
1485         if (ret < 0)
1486                 return ret;
1487         if (!ret)
1488                 return -ENOTCONN;
1489
1490         ret = tb_port_lane_bonding_enable(port);
1491         if (ret) {
1492                 tb_port_warn(port, "failed to enable lane bonding\n");
1493                 return ret;
1494         }
1495
1496         tb_xdomain_update_link_attributes(xd);
1497
1498         dev_dbg(&xd->dev, "lane bonding enabled\n");
1499         return 0;
1500 }
1501 EXPORT_SYMBOL_GPL(tb_xdomain_lane_bonding_enable);
1502
1503 /**
1504  * tb_xdomain_lane_bonding_disable() - Disable lane bonding
1505  * @xd: XDomain connection
1506  *
1507  * Lane bonding is disabled by default for XDomains. If bonding has been
1508  * enabled, this function can be used to disable it.
1509  */
1510 void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd)
1511 {
1512         struct tb_port *port;
1513
1514         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1515         if (port->dual_link_port) {
1516                 tb_port_lane_bonding_disable(port);
1517                 tb_port_disable(port->dual_link_port);
1518                 tb_xdomain_update_link_attributes(xd);
1519
1520                 dev_dbg(&xd->dev, "lane bonding disabled\n");
1521         }
1522 }
1523 EXPORT_SYMBOL_GPL(tb_xdomain_lane_bonding_disable);
1524
1525 /**
1526  * tb_xdomain_enable_paths() - Enable DMA paths for XDomain connection
1527  * @xd: XDomain connection
1528  * @transmit_path: HopID of the transmit path the other end is using to
1529  *                 send packets
1530  * @transmit_ring: DMA ring used to receive packets from the other end
1531  * @receive_path: HopID of the receive path the other end is using to
1532  *                receive packets
1533  * @receive_ring: DMA ring used to send packets to the other end
1534  *
1535  * The function enables DMA paths accordingly so that after successful
1536  * return the caller can send and receive packets using high-speed DMA
1537  * path.
1538  *
1539  * Return: %0 in case of success and negative errno in case of error
1540  */
1541 int tb_xdomain_enable_paths(struct tb_xdomain *xd, u16 transmit_path,
1542                             u16 transmit_ring, u16 receive_path,
1543                             u16 receive_ring)
1544 {
1545         int ret;
1546
1547         mutex_lock(&xd->lock);
1548
1549         if (xd->transmit_path) {
1550                 ret = xd->transmit_path == transmit_path ? 0 : -EBUSY;
1551                 goto exit_unlock;
1552         }
1553
1554         xd->transmit_path = transmit_path;
1555         xd->transmit_ring = transmit_ring;
1556         xd->receive_path = receive_path;
1557         xd->receive_ring = receive_ring;
1558
1559         ret = tb_domain_approve_xdomain_paths(xd->tb, xd);
1560
1561 exit_unlock:
1562         mutex_unlock(&xd->lock);
1563
1564         return ret;
1565 }
1566 EXPORT_SYMBOL_GPL(tb_xdomain_enable_paths);
1567
1568 /**
1569  * tb_xdomain_disable_paths() - Disable DMA paths for XDomain connection
1570  * @xd: XDomain connection
1571  *
1572  * This does the opposite of tb_xdomain_enable_paths(). After call to
1573  * this the caller is not expected to use the rings anymore.
1574  *
1575  * Return: %0 in case of success and negative errno in case of error
1576  */
1577 int tb_xdomain_disable_paths(struct tb_xdomain *xd)
1578 {
1579         int ret = 0;
1580
1581         mutex_lock(&xd->lock);
1582         if (xd->transmit_path) {
1583                 xd->transmit_path = 0;
1584                 xd->transmit_ring = 0;
1585                 xd->receive_path = 0;
1586                 xd->receive_ring = 0;
1587
1588                 ret = tb_domain_disconnect_xdomain_paths(xd->tb, xd);
1589         }
1590         mutex_unlock(&xd->lock);
1591
1592         return ret;
1593 }
1594 EXPORT_SYMBOL_GPL(tb_xdomain_disable_paths);
1595
1596 struct tb_xdomain_lookup {
1597         const uuid_t *uuid;
1598         u8 link;
1599         u8 depth;
1600         u64 route;
1601 };
1602
1603 static struct tb_xdomain *switch_find_xdomain(struct tb_switch *sw,
1604         const struct tb_xdomain_lookup *lookup)
1605 {
1606         struct tb_port *port;
1607
1608         tb_switch_for_each_port(sw, port) {
1609                 struct tb_xdomain *xd;
1610
1611                 if (port->xdomain) {
1612                         xd = port->xdomain;
1613
1614                         if (lookup->uuid) {
1615                                 if (xd->remote_uuid &&
1616                                     uuid_equal(xd->remote_uuid, lookup->uuid))
1617                                         return xd;
1618                         } else if (lookup->link &&
1619                                    lookup->link == xd->link &&
1620                                    lookup->depth == xd->depth) {
1621                                 return xd;
1622                         } else if (lookup->route &&
1623                                    lookup->route == xd->route) {
1624                                 return xd;
1625                         }
1626                 } else if (tb_port_has_remote(port)) {
1627                         xd = switch_find_xdomain(port->remote->sw, lookup);
1628                         if (xd)
1629                                 return xd;
1630                 }
1631         }
1632
1633         return NULL;
1634 }
1635
1636 /**
1637  * tb_xdomain_find_by_uuid() - Find an XDomain by UUID
1638  * @tb: Domain where the XDomain belongs to
1639  * @uuid: UUID to look for
1640  *
1641  * Finds XDomain by walking through the Thunderbolt topology below @tb.
1642  * The returned XDomain will have its reference count increased so the
1643  * caller needs to call tb_xdomain_put() when it is done with the
1644  * object.
1645  *
1646  * This will find all XDomains including the ones that are not yet added
1647  * to the bus (handshake is still in progress).
1648  *
1649  * The caller needs to hold @tb->lock.
1650  */
1651 struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid)
1652 {
1653         struct tb_xdomain_lookup lookup;
1654         struct tb_xdomain *xd;
1655
1656         memset(&lookup, 0, sizeof(lookup));
1657         lookup.uuid = uuid;
1658
1659         xd = switch_find_xdomain(tb->root_switch, &lookup);
1660         return tb_xdomain_get(xd);
1661 }
1662 EXPORT_SYMBOL_GPL(tb_xdomain_find_by_uuid);
1663
1664 /**
1665  * tb_xdomain_find_by_link_depth() - Find an XDomain by link and depth
1666  * @tb: Domain where the XDomain belongs to
1667  * @link: Root switch link number
1668  * @depth: Depth in the link
1669  *
1670  * Finds XDomain by walking through the Thunderbolt topology below @tb.
1671  * The returned XDomain will have its reference count increased so the
1672  * caller needs to call tb_xdomain_put() when it is done with the
1673  * object.
1674  *
1675  * This will find all XDomains including the ones that are not yet added
1676  * to the bus (handshake is still in progress).
1677  *
1678  * The caller needs to hold @tb->lock.
1679  */
1680 struct tb_xdomain *tb_xdomain_find_by_link_depth(struct tb *tb, u8 link,
1681                                                  u8 depth)
1682 {
1683         struct tb_xdomain_lookup lookup;
1684         struct tb_xdomain *xd;
1685
1686         memset(&lookup, 0, sizeof(lookup));
1687         lookup.link = link;
1688         lookup.depth = depth;
1689
1690         xd = switch_find_xdomain(tb->root_switch, &lookup);
1691         return tb_xdomain_get(xd);
1692 }
1693
1694 /**
1695  * tb_xdomain_find_by_route() - Find an XDomain by route string
1696  * @tb: Domain where the XDomain belongs to
1697  * @route: XDomain route string
1698  *
1699  * Finds XDomain by walking through the Thunderbolt topology below @tb.
1700  * The returned XDomain will have its reference count increased so the
1701  * caller needs to call tb_xdomain_put() when it is done with the
1702  * object.
1703  *
1704  * This will find all XDomains including the ones that are not yet added
1705  * to the bus (handshake is still in progress).
1706  *
1707  * The caller needs to hold @tb->lock.
1708  */
1709 struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route)
1710 {
1711         struct tb_xdomain_lookup lookup;
1712         struct tb_xdomain *xd;
1713
1714         memset(&lookup, 0, sizeof(lookup));
1715         lookup.route = route;
1716
1717         xd = switch_find_xdomain(tb->root_switch, &lookup);
1718         return tb_xdomain_get(xd);
1719 }
1720 EXPORT_SYMBOL_GPL(tb_xdomain_find_by_route);
1721
1722 bool tb_xdomain_handle_request(struct tb *tb, enum tb_cfg_pkg_type type,
1723                                const void *buf, size_t size)
1724 {
1725         const struct tb_protocol_handler *handler, *tmp;
1726         const struct tb_xdp_header *hdr = buf;
1727         unsigned int length;
1728         int ret = 0;
1729
1730         /* We expect the packet is at least size of the header */
1731         length = hdr->xd_hdr.length_sn & TB_XDOMAIN_LENGTH_MASK;
1732         if (length != size / 4 - sizeof(hdr->xd_hdr) / 4)
1733                 return true;
1734         if (length < sizeof(*hdr) / 4 - sizeof(hdr->xd_hdr) / 4)
1735                 return true;
1736
1737         /*
1738          * Handle XDomain discovery protocol packets directly here. For
1739          * other protocols (based on their UUID) we call registered
1740          * handlers in turn.
1741          */
1742         if (uuid_equal(&hdr->uuid, &tb_xdp_uuid)) {
1743                 if (type == TB_CFG_PKG_XDOMAIN_REQ)
1744                         return tb_xdp_schedule_request(tb, hdr, size);
1745                 return false;
1746         }
1747
1748         mutex_lock(&xdomain_lock);
1749         list_for_each_entry_safe(handler, tmp, &protocol_handlers, list) {
1750                 if (!uuid_equal(&hdr->uuid, handler->uuid))
1751                         continue;
1752
1753                 mutex_unlock(&xdomain_lock);
1754                 ret = handler->callback(buf, size, handler->data);
1755                 mutex_lock(&xdomain_lock);
1756
1757                 if (ret)
1758                         break;
1759         }
1760         mutex_unlock(&xdomain_lock);
1761
1762         return ret > 0;
1763 }
1764
1765 static int update_xdomain(struct device *dev, void *data)
1766 {
1767         struct tb_xdomain *xd;
1768
1769         xd = tb_to_xdomain(dev);
1770         if (xd) {
1771                 queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
1772                                    msecs_to_jiffies(50));
1773         }
1774
1775         return 0;
1776 }
1777
1778 static void update_all_xdomains(void)
1779 {
1780         bus_for_each_dev(&tb_bus_type, NULL, NULL, update_xdomain);
1781 }
1782
1783 static bool remove_directory(const char *key, const struct tb_property_dir *dir)
1784 {
1785         struct tb_property *p;
1786
1787         p = tb_property_find(xdomain_property_dir, key,
1788                              TB_PROPERTY_TYPE_DIRECTORY);
1789         if (p && p->value.dir == dir) {
1790                 tb_property_remove(p);
1791                 return true;
1792         }
1793         return false;
1794 }
1795
1796 /**
1797  * tb_register_property_dir() - Register property directory to the host
1798  * @key: Key (name) of the directory to add
1799  * @dir: Directory to add
1800  *
1801  * Service drivers can use this function to add new property directory
1802  * to the host available properties. The other connected hosts are
1803  * notified so they can re-read properties of this host if they are
1804  * interested.
1805  *
1806  * Return: %0 on success and negative errno on failure
1807  */
1808 int tb_register_property_dir(const char *key, struct tb_property_dir *dir)
1809 {
1810         int ret;
1811
1812         if (WARN_ON(!xdomain_property_dir))
1813                 return -EAGAIN;
1814
1815         if (!key || strlen(key) > 8)
1816                 return -EINVAL;
1817
1818         mutex_lock(&xdomain_lock);
1819         if (tb_property_find(xdomain_property_dir, key,
1820                              TB_PROPERTY_TYPE_DIRECTORY)) {
1821                 ret = -EEXIST;
1822                 goto err_unlock;
1823         }
1824
1825         ret = tb_property_add_dir(xdomain_property_dir, key, dir);
1826         if (ret)
1827                 goto err_unlock;
1828
1829         ret = rebuild_property_block();
1830         if (ret) {
1831                 remove_directory(key, dir);
1832                 goto err_unlock;
1833         }
1834
1835         mutex_unlock(&xdomain_lock);
1836         update_all_xdomains();
1837         return 0;
1838
1839 err_unlock:
1840         mutex_unlock(&xdomain_lock);
1841         return ret;
1842 }
1843 EXPORT_SYMBOL_GPL(tb_register_property_dir);
1844
1845 /**
1846  * tb_unregister_property_dir() - Removes property directory from host
1847  * @key: Key (name) of the directory
1848  * @dir: Directory to remove
1849  *
1850  * This will remove the existing directory from this host and notify the
1851  * connected hosts about the change.
1852  */
1853 void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir)
1854 {
1855         int ret = 0;
1856
1857         mutex_lock(&xdomain_lock);
1858         if (remove_directory(key, dir))
1859                 ret = rebuild_property_block();
1860         mutex_unlock(&xdomain_lock);
1861
1862         if (!ret)
1863                 update_all_xdomains();
1864 }
1865 EXPORT_SYMBOL_GPL(tb_unregister_property_dir);
1866
1867 int tb_xdomain_init(void)
1868 {
1869         xdomain_property_dir = tb_property_create_dir(NULL);
1870         if (!xdomain_property_dir)
1871                 return -ENOMEM;
1872
1873         /*
1874          * Initialize standard set of properties without any service
1875          * directories. Those will be added by service drivers
1876          * themselves when they are loaded.
1877          *
1878          * We also add node name later when first connection is made.
1879          */
1880         tb_property_add_immediate(xdomain_property_dir, "vendorid",
1881                                   PCI_VENDOR_ID_INTEL);
1882         tb_property_add_text(xdomain_property_dir, "vendorid", "Intel Corp.");
1883         tb_property_add_immediate(xdomain_property_dir, "deviceid", 0x1);
1884         tb_property_add_immediate(xdomain_property_dir, "devicerv", 0x80000100);
1885
1886         return 0;
1887 }
1888
1889 void tb_xdomain_exit(void)
1890 {
1891         kfree(xdomain_property_block);
1892         tb_property_free_dir(xdomain_property_dir);
1893 }