1 /*
2 * Intel MIC Platform Software Stack (MPSS)
3 *
4 * Copyright(c) 2015 Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2, as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * Intel SCIF driver.
16 *
17 */
18 #include <linux/dma_remapping.h>
19 #include <linux/pagemap.h>
20 #include <linux/sched/mm.h>
21 #include <linux/sched/signal.h>
22
23 #include "scif_main.h"
24 #include "scif_map.h"
25
26 /* Used to skip ulimit checks for registrations with SCIF_MAP_KERNEL flag */
27 #define SCIF_MAP_ULIMIT 0x40
28
29 bool scif_ulimit_check = 1;
30
31 /**
32 * scif_rma_ep_init:
33 * @ep: end point
34 *
35 * Initialize RMA per EP data structures.
36 */
scif_rma_ep_init(struct scif_endpt * ep)37 void scif_rma_ep_init(struct scif_endpt *ep)
38 {
39 struct scif_endpt_rma_info *rma = &ep->rma_info;
40
41 mutex_init(&rma->rma_lock);
42 init_iova_domain(&rma->iovad, PAGE_SIZE, SCIF_IOVA_START_PFN);
43 spin_lock_init(&rma->tc_lock);
44 mutex_init(&rma->mmn_lock);
45 INIT_LIST_HEAD(&rma->reg_list);
46 INIT_LIST_HEAD(&rma->remote_reg_list);
47 atomic_set(&rma->tw_refcount, 0);
48 atomic_set(&rma->tcw_refcount, 0);
49 atomic_set(&rma->tcw_total_pages, 0);
50 atomic_set(&rma->fence_refcount, 0);
51
52 rma->async_list_del = 0;
53 rma->dma_chan = NULL;
54 INIT_LIST_HEAD(&rma->mmn_list);
55 INIT_LIST_HEAD(&rma->vma_list);
56 init_waitqueue_head(&rma->markwq);
57 }
58
59 /**
60 * scif_rma_ep_can_uninit:
61 * @ep: end point
62 *
63 * Returns 1 if an endpoint can be uninitialized and 0 otherwise.
64 */
scif_rma_ep_can_uninit(struct scif_endpt * ep)65 int scif_rma_ep_can_uninit(struct scif_endpt *ep)
66 {
67 int ret = 0;
68
69 mutex_lock(&ep->rma_info.rma_lock);
70 /* Destroy RMA Info only if both lists are empty */
71 if (list_empty(&ep->rma_info.reg_list) &&
72 list_empty(&ep->rma_info.remote_reg_list) &&
73 list_empty(&ep->rma_info.mmn_list) &&
74 !atomic_read(&ep->rma_info.tw_refcount) &&
75 !atomic_read(&ep->rma_info.tcw_refcount) &&
76 !atomic_read(&ep->rma_info.fence_refcount))
77 ret = 1;
78 mutex_unlock(&ep->rma_info.rma_lock);
79 return ret;
80 }
81
82 /**
83 * scif_create_pinned_pages:
84 * @nr_pages: number of pages in window
85 * @prot: read/write protection
86 *
87 * Allocate and prepare a set of pinned pages.
88 */
89 static struct scif_pinned_pages *
scif_create_pinned_pages(int nr_pages,int prot)90 scif_create_pinned_pages(int nr_pages, int prot)
91 {
92 struct scif_pinned_pages *pin;
93
94 might_sleep();
95 pin = scif_zalloc(sizeof(*pin));
96 if (!pin)
97 goto error;
98
99 pin->pages = scif_zalloc(nr_pages * sizeof(*pin->pages));
100 if (!pin->pages)
101 goto error_free_pinned_pages;
102
103 pin->prot = prot;
104 pin->magic = SCIFEP_MAGIC;
105 return pin;
106
107 error_free_pinned_pages:
108 scif_free(pin, sizeof(*pin));
109 error:
110 return NULL;
111 }
112
113 /**
114 * scif_destroy_pinned_pages:
115 * @pin: A set of pinned pages.
116 *
117 * Deallocate resources for pinned pages.
118 */
scif_destroy_pinned_pages(struct scif_pinned_pages * pin)119 static int scif_destroy_pinned_pages(struct scif_pinned_pages *pin)
120 {
121 int j;
122 int writeable = pin->prot & SCIF_PROT_WRITE;
123 int kernel = SCIF_MAP_KERNEL & pin->map_flags;
124
125 for (j = 0; j < pin->nr_pages; j++) {
126 if (pin->pages[j] && !kernel) {
127 if (writeable)
128 SetPageDirty(pin->pages[j]);
129 put_page(pin->pages[j]);
130 }
131 }
132
133 scif_free(pin->pages,
134 pin->nr_pages * sizeof(*pin->pages));
135 scif_free(pin, sizeof(*pin));
136 return 0;
137 }
138
139 /*
140 * scif_create_window:
141 * @ep: end point
142 * @nr_pages: number of pages
143 * @offset: registration offset
144 * @temp: true if a temporary window is being created
145 *
146 * Allocate and prepare a self registration window.
147 */
scif_create_window(struct scif_endpt * ep,int nr_pages,s64 offset,bool temp)148 struct scif_window *scif_create_window(struct scif_endpt *ep, int nr_pages,
149 s64 offset, bool temp)
150 {
151 struct scif_window *window;
152
153 might_sleep();
154 window = scif_zalloc(sizeof(*window));
155 if (!window)
156 goto error;
157
158 window->dma_addr = scif_zalloc(nr_pages * sizeof(*window->dma_addr));
159 if (!window->dma_addr)
160 goto error_free_window;
161
162 window->num_pages = scif_zalloc(nr_pages * sizeof(*window->num_pages));
163 if (!window->num_pages)
164 goto error_free_window;
165
166 window->offset = offset;
167 window->ep = (u64)ep;
168 window->magic = SCIFEP_MAGIC;
169 window->reg_state = OP_IDLE;
170 init_waitqueue_head(&window->regwq);
171 window->unreg_state = OP_IDLE;
172 init_waitqueue_head(&window->unregwq);
173 INIT_LIST_HEAD(&window->list);
174 window->type = SCIF_WINDOW_SELF;
175 window->temp = temp;
176 return window;
177
178 error_free_window:
179 scif_free(window->dma_addr,
180 nr_pages * sizeof(*window->dma_addr));
181 scif_free(window, sizeof(*window));
182 error:
183 return NULL;
184 }
185
186 /**
187 * scif_destroy_incomplete_window:
188 * @ep: end point
189 * @window: registration window
190 *
191 * Deallocate resources for self window.
192 */
scif_destroy_incomplete_window(struct scif_endpt * ep,struct scif_window * window)193 static void scif_destroy_incomplete_window(struct scif_endpt *ep,
194 struct scif_window *window)
195 {
196 int err;
197 int nr_pages = window->nr_pages;
198 struct scif_allocmsg *alloc = &window->alloc_handle;
199 struct scifmsg msg;
200
201 retry:
202 /* Wait for a SCIF_ALLOC_GNT/REJ message */
203 err = wait_event_timeout(alloc->allocwq,
204 alloc->state != OP_IN_PROGRESS,
205 SCIF_NODE_ALIVE_TIMEOUT);
206 if (!err && scifdev_alive(ep))
207 goto retry;
208
209 mutex_lock(&ep->rma_info.rma_lock);
210 if (alloc->state == OP_COMPLETED) {
211 msg.uop = SCIF_FREE_VIRT;
212 msg.src = ep->port;
213 msg.payload[0] = ep->remote_ep;
214 msg.payload[1] = window->alloc_handle.vaddr;
215 msg.payload[2] = (u64)window;
216 msg.payload[3] = SCIF_REGISTER;
217 _scif_nodeqp_send(ep->remote_dev, &msg);
218 }
219 mutex_unlock(&ep->rma_info.rma_lock);
220
221 scif_free_window_offset(ep, window, window->offset);
222 scif_free(window->dma_addr, nr_pages * sizeof(*window->dma_addr));
223 scif_free(window->num_pages, nr_pages * sizeof(*window->num_pages));
224 scif_free(window, sizeof(*window));
225 }
226
227 /**
228 * scif_unmap_window:
229 * @remote_dev: SCIF remote device
230 * @window: registration window
231 *
232 * Delete any DMA mappings created for a registered self window
233 */
scif_unmap_window(struct scif_dev * remote_dev,struct scif_window * window)234 void scif_unmap_window(struct scif_dev *remote_dev, struct scif_window *window)
235 {
236 int j;
237
238 if (scif_is_iommu_enabled() && !scifdev_self(remote_dev)) {
239 if (window->st) {
240 dma_unmap_sg(&remote_dev->sdev->dev,
241 window->st->sgl, window->st->nents,
242 DMA_BIDIRECTIONAL);
243 sg_free_table(window->st);
244 kfree(window->st);
245 window->st = NULL;
246 }
247 } else {
248 for (j = 0; j < window->nr_contig_chunks; j++) {
249 if (window->dma_addr[j]) {
250 scif_unmap_single(window->dma_addr[j],
251 remote_dev,
252 window->num_pages[j] <<
253 PAGE_SHIFT);
254 window->dma_addr[j] = 0x0;
255 }
256 }
257 }
258 }
259
__scif_acquire_mm(void)260 static inline struct mm_struct *__scif_acquire_mm(void)
261 {
262 if (scif_ulimit_check)
263 return get_task_mm(current);
264 return NULL;
265 }
266
__scif_release_mm(struct mm_struct * mm)267 static inline void __scif_release_mm(struct mm_struct *mm)
268 {
269 if (mm)
270 mmput(mm);
271 }
272
273 static inline int
__scif_dec_pinned_vm_lock(struct mm_struct * mm,int nr_pages,bool try_lock)274 __scif_dec_pinned_vm_lock(struct mm_struct *mm,
275 int nr_pages, bool try_lock)
276 {
277 if (!mm || !nr_pages || !scif_ulimit_check)
278 return 0;
279 if (try_lock) {
280 if (!down_write_trylock(&mm->mmap_sem)) {
281 dev_err(scif_info.mdev.this_device,
282 "%s %d err\n", __func__, __LINE__);
283 return -1;
284 }
285 } else {
286 down_write(&mm->mmap_sem);
287 }
288 mm->pinned_vm -= nr_pages;
289 up_write(&mm->mmap_sem);
290 return 0;
291 }
292
__scif_check_inc_pinned_vm(struct mm_struct * mm,int nr_pages)293 static inline int __scif_check_inc_pinned_vm(struct mm_struct *mm,
294 int nr_pages)
295 {
296 unsigned long locked, lock_limit;
297
298 if (!mm || !nr_pages || !scif_ulimit_check)
299 return 0;
300
301 locked = nr_pages;
302 locked += mm->pinned_vm;
303 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
304 if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
305 dev_err(scif_info.mdev.this_device,
306 "locked(%lu) > lock_limit(%lu)\n",
307 locked, lock_limit);
308 return -ENOMEM;
309 }
310 mm->pinned_vm = locked;
311 return 0;
312 }
313
314 /**
315 * scif_destroy_window:
316 * @ep: end point
317 * @window: registration window
318 *
319 * Deallocate resources for self window.
320 */
scif_destroy_window(struct scif_endpt * ep,struct scif_window * window)321 int scif_destroy_window(struct scif_endpt *ep, struct scif_window *window)
322 {
323 int j;
324 struct scif_pinned_pages *pinned_pages = window->pinned_pages;
325 int nr_pages = window->nr_pages;
326
327 might_sleep();
328 if (!window->temp && window->mm) {
329 __scif_dec_pinned_vm_lock(window->mm, window->nr_pages, 0);
330 __scif_release_mm(window->mm);
331 window->mm = NULL;
332 }
333
334 scif_free_window_offset(ep, window, window->offset);
335 scif_unmap_window(ep->remote_dev, window);
336 /*
337 * Decrement references for this set of pinned pages from
338 * this window.
339 */
340 j = atomic_sub_return(1, &pinned_pages->ref_count);
341 if (j < 0)
342 dev_err(scif_info.mdev.this_device,
343 "%s %d incorrect ref count %d\n",
344 __func__, __LINE__, j);
345 /*
346 * If the ref count for pinned_pages is zero then someone
347 * has already called scif_unpin_pages() for it and we should
348 * destroy the page cache.
349 */
350 if (!j)
351 scif_destroy_pinned_pages(window->pinned_pages);
352 scif_free(window->dma_addr, nr_pages * sizeof(*window->dma_addr));
353 scif_free(window->num_pages, nr_pages * sizeof(*window->num_pages));
354 window->magic = 0;
355 scif_free(window, sizeof(*window));
356 return 0;
357 }
358
359 /**
360 * scif_create_remote_lookup:
361 * @remote_dev: SCIF remote device
362 * @window: remote window
363 *
364 * Allocate and prepare lookup entries for the remote
365 * end to copy over the physical addresses.
366 * Returns 0 on success and appropriate errno on failure.
367 */
scif_create_remote_lookup(struct scif_dev * remote_dev,struct scif_window * window)368 static int scif_create_remote_lookup(struct scif_dev *remote_dev,
369 struct scif_window *window)
370 {
371 int i, j, err = 0;
372 int nr_pages = window->nr_pages;
373 bool vmalloc_dma_phys, vmalloc_num_pages;
374
375 might_sleep();
376 /* Map window */
377 err = scif_map_single(&window->mapped_offset,
378 window, remote_dev, sizeof(*window));
379 if (err)
380 goto error_window;
381
382 /* Compute the number of lookup entries. 21 == 2MB Shift */
383 window->nr_lookup = ALIGN(nr_pages * PAGE_SIZE,
384 ((2) * 1024 * 1024)) >> 21;
385
386 window->dma_addr_lookup.lookup =
387 scif_alloc_coherent(&window->dma_addr_lookup.offset,
388 remote_dev, window->nr_lookup *
389 sizeof(*window->dma_addr_lookup.lookup),
390 GFP_KERNEL | __GFP_ZERO);
391 if (!window->dma_addr_lookup.lookup) {
392 err = -ENOMEM;
393 goto error_window;
394 }
395
396 window->num_pages_lookup.lookup =
397 scif_alloc_coherent(&window->num_pages_lookup.offset,
398 remote_dev, window->nr_lookup *
399 sizeof(*window->num_pages_lookup.lookup),
400 GFP_KERNEL | __GFP_ZERO);
401 if (!window->num_pages_lookup.lookup) {
402 err = -ENOMEM;
403 goto error_window;
404 }
405
406 vmalloc_dma_phys = is_vmalloc_addr(&window->dma_addr[0]);
407 vmalloc_num_pages = is_vmalloc_addr(&window->num_pages[0]);
408
409 /* Now map each of the pages containing physical addresses */
410 for (i = 0, j = 0; i < nr_pages; i += SCIF_NR_ADDR_IN_PAGE, j++) {
411 err = scif_map_page(&window->dma_addr_lookup.lookup[j],
412 vmalloc_dma_phys ?
413 vmalloc_to_page(&window->dma_addr[i]) :
414 virt_to_page(&window->dma_addr[i]),
415 remote_dev);
416 if (err)
417 goto error_window;
418 err = scif_map_page(&window->num_pages_lookup.lookup[j],
419 vmalloc_num_pages ?
420 vmalloc_to_page(&window->num_pages[i]) :
421 virt_to_page(&window->num_pages[i]),
422 remote_dev);
423 if (err)
424 goto error_window;
425 }
426 return 0;
427 error_window:
428 return err;
429 }
430
431 /**
432 * scif_destroy_remote_lookup:
433 * @remote_dev: SCIF remote device
434 * @window: remote window
435 *
436 * Destroy lookup entries used for the remote
437 * end to copy over the physical addresses.
438 */
scif_destroy_remote_lookup(struct scif_dev * remote_dev,struct scif_window * window)439 static void scif_destroy_remote_lookup(struct scif_dev *remote_dev,
440 struct scif_window *window)
441 {
442 int i, j;
443
444 if (window->nr_lookup) {
445 struct scif_rma_lookup *lup = &window->dma_addr_lookup;
446 struct scif_rma_lookup *npup = &window->num_pages_lookup;
447
448 for (i = 0, j = 0; i < window->nr_pages;
449 i += SCIF_NR_ADDR_IN_PAGE, j++) {
450 if (lup->lookup && lup->lookup[j])
451 scif_unmap_single(lup->lookup[j],
452 remote_dev,
453 PAGE_SIZE);
454 if (npup->lookup && npup->lookup[j])
455 scif_unmap_single(npup->lookup[j],
456 remote_dev,
457 PAGE_SIZE);
458 }
459 if (lup->lookup)
460 scif_free_coherent(lup->lookup, lup->offset,
461 remote_dev, window->nr_lookup *
462 sizeof(*lup->lookup));
463 if (npup->lookup)
464 scif_free_coherent(npup->lookup, npup->offset,
465 remote_dev, window->nr_lookup *
466 sizeof(*npup->lookup));
467 if (window->mapped_offset)
468 scif_unmap_single(window->mapped_offset,
469 remote_dev, sizeof(*window));
470 window->nr_lookup = 0;
471 }
472 }
473
474 /**
475 * scif_create_remote_window:
476 * @ep: end point
477 * @nr_pages: number of pages in window
478 *
479 * Allocate and prepare a remote registration window.
480 */
481 static struct scif_window *
scif_create_remote_window(struct scif_dev * scifdev,int nr_pages)482 scif_create_remote_window(struct scif_dev *scifdev, int nr_pages)
483 {
484 struct scif_window *window;
485
486 might_sleep();
487 window = scif_zalloc(sizeof(*window));
488 if (!window)
489 goto error_ret;
490
491 window->magic = SCIFEP_MAGIC;
492 window->nr_pages = nr_pages;
493
494 window->dma_addr = scif_zalloc(nr_pages * sizeof(*window->dma_addr));
495 if (!window->dma_addr)
496 goto error_window;
497
498 window->num_pages = scif_zalloc(nr_pages *
499 sizeof(*window->num_pages));
500 if (!window->num_pages)
501 goto error_window;
502
503 if (scif_create_remote_lookup(scifdev, window))
504 goto error_window;
505
506 window->type = SCIF_WINDOW_PEER;
507 window->unreg_state = OP_IDLE;
508 INIT_LIST_HEAD(&window->list);
509 return window;
510 error_window:
511 scif_destroy_remote_window(window);
512 error_ret:
513 return NULL;
514 }
515
516 /**
517 * scif_destroy_remote_window:
518 * @ep: end point
519 * @window: remote registration window
520 *
521 * Deallocate resources for remote window.
522 */
523 void
scif_destroy_remote_window(struct scif_window * window)524 scif_destroy_remote_window(struct scif_window *window)
525 {
526 scif_free(window->dma_addr, window->nr_pages *
527 sizeof(*window->dma_addr));
528 scif_free(window->num_pages, window->nr_pages *
529 sizeof(*window->num_pages));
530 window->magic = 0;
531 scif_free(window, sizeof(*window));
532 }
533
534 /**
535 * scif_iommu_map: create DMA mappings if the IOMMU is enabled
536 * @remote_dev: SCIF remote device
537 * @window: remote registration window
538 *
539 * Map the physical pages using dma_map_sg(..) and then detect the number
540 * of contiguous DMA mappings allocated
541 */
scif_iommu_map(struct scif_dev * remote_dev,struct scif_window * window)542 static int scif_iommu_map(struct scif_dev *remote_dev,
543 struct scif_window *window)
544 {
545 struct scatterlist *sg;
546 int i, err;
547 scif_pinned_pages_t pin = window->pinned_pages;
548
549 window->st = kzalloc(sizeof(*window->st), GFP_KERNEL);
550 if (!window->st)
551 return -ENOMEM;
552
553 err = sg_alloc_table(window->st, window->nr_pages, GFP_KERNEL);
554 if (err)
555 return err;
556
557 for_each_sg(window->st->sgl, sg, window->st->nents, i)
558 sg_set_page(sg, pin->pages[i], PAGE_SIZE, 0x0);
559
560 err = dma_map_sg(&remote_dev->sdev->dev, window->st->sgl,
561 window->st->nents, DMA_BIDIRECTIONAL);
562 if (!err)
563 return -ENOMEM;
564 /* Detect contiguous ranges of DMA mappings */
565 sg = window->st->sgl;
566 for (i = 0; sg; i++) {
567 dma_addr_t last_da;
568
569 window->dma_addr[i] = sg_dma_address(sg);
570 window->num_pages[i] = sg_dma_len(sg) >> PAGE_SHIFT;
571 last_da = sg_dma_address(sg) + sg_dma_len(sg);
572 while ((sg = sg_next(sg)) && sg_dma_address(sg) == last_da) {
573 window->num_pages[i] +=
574 (sg_dma_len(sg) >> PAGE_SHIFT);
575 last_da = window->dma_addr[i] +
576 sg_dma_len(sg);
577 }
578 window->nr_contig_chunks++;
579 }
580 return 0;
581 }
582
583 /**
584 * scif_map_window:
585 * @remote_dev: SCIF remote device
586 * @window: self registration window
587 *
588 * Map pages of a window into the aperture/PCI.
589 * Also determine addresses required for DMA.
590 */
591 int
scif_map_window(struct scif_dev * remote_dev,struct scif_window * window)592 scif_map_window(struct scif_dev *remote_dev, struct scif_window *window)
593 {
594 int i, j, k, err = 0, nr_contig_pages;
595 scif_pinned_pages_t pin;
596 phys_addr_t phys_prev, phys_curr;
597
598 might_sleep();
599
600 pin = window->pinned_pages;
601
602 if (intel_iommu_enabled && !scifdev_self(remote_dev))
603 return scif_iommu_map(remote_dev, window);
604
605 for (i = 0, j = 0; i < window->nr_pages; i += nr_contig_pages, j++) {
606 phys_prev = page_to_phys(pin->pages[i]);
607 nr_contig_pages = 1;
608
609 /* Detect physically contiguous chunks */
610 for (k = i + 1; k < window->nr_pages; k++) {
611 phys_curr = page_to_phys(pin->pages[k]);
612 if (phys_curr != (phys_prev + PAGE_SIZE))
613 break;
614 phys_prev = phys_curr;
615 nr_contig_pages++;
616 }
617 window->num_pages[j] = nr_contig_pages;
618 window->nr_contig_chunks++;
619 if (scif_is_mgmt_node()) {
620 /*
621 * Management node has to deal with SMPT on X100 and
622 * hence the DMA mapping is required
623 */
624 err = scif_map_single(&window->dma_addr[j],
625 phys_to_virt(page_to_phys(
626 pin->pages[i])),
627 remote_dev,
628 nr_contig_pages << PAGE_SHIFT);
629 if (err)
630 return err;
631 } else {
632 window->dma_addr[j] = page_to_phys(pin->pages[i]);
633 }
634 }
635 return err;
636 }
637
638 /**
639 * scif_send_scif_unregister:
640 * @ep: end point
641 * @window: self registration window
642 *
643 * Send a SCIF_UNREGISTER message.
644 */
scif_send_scif_unregister(struct scif_endpt * ep,struct scif_window * window)645 static int scif_send_scif_unregister(struct scif_endpt *ep,
646 struct scif_window *window)
647 {
648 struct scifmsg msg;
649
650 msg.uop = SCIF_UNREGISTER;
651 msg.src = ep->port;
652 msg.payload[0] = window->alloc_handle.vaddr;
653 msg.payload[1] = (u64)window;
654 return scif_nodeqp_send(ep->remote_dev, &msg);
655 }
656
657 /**
658 * scif_unregister_window:
659 * @window: self registration window
660 *
661 * Send an unregistration request and wait for a response.
662 */
scif_unregister_window(struct scif_window * window)663 int scif_unregister_window(struct scif_window *window)
664 {
665 int err = 0;
666 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
667 bool send_msg = false;
668
669 might_sleep();
670 switch (window->unreg_state) {
671 case OP_IDLE:
672 {
673 window->unreg_state = OP_IN_PROGRESS;
674 send_msg = true;
675 /* fall through */
676 }
677 case OP_IN_PROGRESS:
678 {
679 scif_get_window(window, 1);
680 mutex_unlock(&ep->rma_info.rma_lock);
681 if (send_msg) {
682 err = scif_send_scif_unregister(ep, window);
683 if (err) {
684 window->unreg_state = OP_COMPLETED;
685 goto done;
686 }
687 } else {
688 /* Return ENXIO since unregistration is in progress */
689 mutex_lock(&ep->rma_info.rma_lock);
690 return -ENXIO;
691 }
692 retry:
693 /* Wait for a SCIF_UNREGISTER_(N)ACK message */
694 err = wait_event_timeout(window->unregwq,
695 window->unreg_state != OP_IN_PROGRESS,
696 SCIF_NODE_ALIVE_TIMEOUT);
697 if (!err && scifdev_alive(ep))
698 goto retry;
699 if (!err) {
700 err = -ENODEV;
701 window->unreg_state = OP_COMPLETED;
702 dev_err(scif_info.mdev.this_device,
703 "%s %d err %d\n", __func__, __LINE__, err);
704 }
705 if (err > 0)
706 err = 0;
707 done:
708 mutex_lock(&ep->rma_info.rma_lock);
709 scif_put_window(window, 1);
710 break;
711 }
712 case OP_FAILED:
713 {
714 if (!scifdev_alive(ep)) {
715 err = -ENODEV;
716 window->unreg_state = OP_COMPLETED;
717 }
718 break;
719 }
720 case OP_COMPLETED:
721 break;
722 default:
723 err = -ENODEV;
724 }
725
726 if (window->unreg_state == OP_COMPLETED && window->ref_count)
727 scif_put_window(window, window->nr_pages);
728
729 if (!window->ref_count) {
730 atomic_inc(&ep->rma_info.tw_refcount);
731 list_del_init(&window->list);
732 scif_free_window_offset(ep, window, window->offset);
733 mutex_unlock(&ep->rma_info.rma_lock);
734 if ((!!(window->pinned_pages->map_flags & SCIF_MAP_KERNEL)) &&
735 scifdev_alive(ep)) {
736 scif_drain_dma_intr(ep->remote_dev->sdev,
737 ep->rma_info.dma_chan);
738 } else {
739 if (!__scif_dec_pinned_vm_lock(window->mm,
740 window->nr_pages, 1)) {
741 __scif_release_mm(window->mm);
742 window->mm = NULL;
743 }
744 }
745 scif_queue_for_cleanup(window, &scif_info.rma);
746 mutex_lock(&ep->rma_info.rma_lock);
747 }
748 return err;
749 }
750
751 /**
752 * scif_send_alloc_request:
753 * @ep: end point
754 * @window: self registration window
755 *
756 * Send a remote window allocation request
757 */
scif_send_alloc_request(struct scif_endpt * ep,struct scif_window * window)758 static int scif_send_alloc_request(struct scif_endpt *ep,
759 struct scif_window *window)
760 {
761 struct scifmsg msg;
762 struct scif_allocmsg *alloc = &window->alloc_handle;
763
764 /* Set up the Alloc Handle */
765 alloc->state = OP_IN_PROGRESS;
766 init_waitqueue_head(&alloc->allocwq);
767
768 /* Send out an allocation request */
769 msg.uop = SCIF_ALLOC_REQ;
770 msg.payload[1] = window->nr_pages;
771 msg.payload[2] = (u64)&window->alloc_handle;
772 return _scif_nodeqp_send(ep->remote_dev, &msg);
773 }
774
775 /**
776 * scif_prep_remote_window:
777 * @ep: end point
778 * @window: self registration window
779 *
780 * Send a remote window allocation request, wait for an allocation response,
781 * and prepares the remote window by copying over the page lists
782 */
scif_prep_remote_window(struct scif_endpt * ep,struct scif_window * window)783 static int scif_prep_remote_window(struct scif_endpt *ep,
784 struct scif_window *window)
785 {
786 struct scifmsg msg;
787 struct scif_window *remote_window;
788 struct scif_allocmsg *alloc = &window->alloc_handle;
789 dma_addr_t *dma_phys_lookup, *tmp, *num_pages_lookup, *tmp1;
790 int i = 0, j = 0;
791 int nr_contig_chunks, loop_nr_contig_chunks;
792 int remaining_nr_contig_chunks, nr_lookup;
793 int err, map_err;
794
795 map_err = scif_map_window(ep->remote_dev, window);
796 if (map_err)
797 dev_err(&ep->remote_dev->sdev->dev,
798 "%s %d map_err %d\n", __func__, __LINE__, map_err);
799 remaining_nr_contig_chunks = window->nr_contig_chunks;
800 nr_contig_chunks = window->nr_contig_chunks;
801 retry:
802 /* Wait for a SCIF_ALLOC_GNT/REJ message */
803 err = wait_event_timeout(alloc->allocwq,
804 alloc->state != OP_IN_PROGRESS,
805 SCIF_NODE_ALIVE_TIMEOUT);
806 mutex_lock(&ep->rma_info.rma_lock);
807 /* Synchronize with the thread waking up allocwq */
808 mutex_unlock(&ep->rma_info.rma_lock);
809 if (!err && scifdev_alive(ep))
810 goto retry;
811
812 if (!err)
813 err = -ENODEV;
814
815 if (err > 0)
816 err = 0;
817 else
818 return err;
819
820 /* Bail out. The remote end rejected this request */
821 if (alloc->state == OP_FAILED)
822 return -ENOMEM;
823
824 if (map_err) {
825 dev_err(&ep->remote_dev->sdev->dev,
826 "%s %d err %d\n", __func__, __LINE__, map_err);
827 msg.uop = SCIF_FREE_VIRT;
828 msg.src = ep->port;
829 msg.payload[0] = ep->remote_ep;
830 msg.payload[1] = window->alloc_handle.vaddr;
831 msg.payload[2] = (u64)window;
832 msg.payload[3] = SCIF_REGISTER;
833 spin_lock(&ep->lock);
834 if (ep->state == SCIFEP_CONNECTED)
835 err = _scif_nodeqp_send(ep->remote_dev, &msg);
836 else
837 err = -ENOTCONN;
838 spin_unlock(&ep->lock);
839 return err;
840 }
841
842 remote_window = scif_ioremap(alloc->phys_addr, sizeof(*window),
843 ep->remote_dev);
844
845 /* Compute the number of lookup entries. 21 == 2MB Shift */
846 nr_lookup = ALIGN(nr_contig_chunks, SCIF_NR_ADDR_IN_PAGE)
847 >> ilog2(SCIF_NR_ADDR_IN_PAGE);
848
849 dma_phys_lookup =
850 scif_ioremap(remote_window->dma_addr_lookup.offset,
851 nr_lookup *
852 sizeof(*remote_window->dma_addr_lookup.lookup),
853 ep->remote_dev);
854 num_pages_lookup =
855 scif_ioremap(remote_window->num_pages_lookup.offset,
856 nr_lookup *
857 sizeof(*remote_window->num_pages_lookup.lookup),
858 ep->remote_dev);
859
860 while (remaining_nr_contig_chunks) {
861 loop_nr_contig_chunks = min_t(int, remaining_nr_contig_chunks,
862 (int)SCIF_NR_ADDR_IN_PAGE);
863 /* #1/2 - Copy physical addresses over to the remote side */
864
865 /* #2/2 - Copy DMA addresses (addresses that are fed into the
866 * DMA engine) We transfer bus addresses which are then
867 * converted into a MIC physical address on the remote
868 * side if it is a MIC, if the remote node is a mgmt node we
869 * transfer the MIC physical address
870 */
871 tmp = scif_ioremap(dma_phys_lookup[j],
872 loop_nr_contig_chunks *
873 sizeof(*window->dma_addr),
874 ep->remote_dev);
875 tmp1 = scif_ioremap(num_pages_lookup[j],
876 loop_nr_contig_chunks *
877 sizeof(*window->num_pages),
878 ep->remote_dev);
879 if (scif_is_mgmt_node()) {
880 memcpy_toio((void __force __iomem *)tmp,
881 &window->dma_addr[i], loop_nr_contig_chunks
882 * sizeof(*window->dma_addr));
883 memcpy_toio((void __force __iomem *)tmp1,
884 &window->num_pages[i], loop_nr_contig_chunks
885 * sizeof(*window->num_pages));
886 } else {
887 if (scifdev_is_p2p(ep->remote_dev)) {
888 /*
889 * add remote node's base address for this node
890 * to convert it into a MIC address
891 */
892 int m;
893 dma_addr_t dma_addr;
894
895 for (m = 0; m < loop_nr_contig_chunks; m++) {
896 dma_addr = window->dma_addr[i + m] +
897 ep->remote_dev->base_addr;
898 writeq(dma_addr,
899 (void __force __iomem *)&tmp[m]);
900 }
901 memcpy_toio((void __force __iomem *)tmp1,
902 &window->num_pages[i],
903 loop_nr_contig_chunks
904 * sizeof(*window->num_pages));
905 } else {
906 /* Mgmt node or loopback - transfer DMA
907 * addresses as is, this is the same as a
908 * MIC physical address (we use the dma_addr
909 * and not the phys_addr array since the
910 * phys_addr is only setup if there is a mmap()
911 * request from the mgmt node)
912 */
913 memcpy_toio((void __force __iomem *)tmp,
914 &window->dma_addr[i],
915 loop_nr_contig_chunks *
916 sizeof(*window->dma_addr));
917 memcpy_toio((void __force __iomem *)tmp1,
918 &window->num_pages[i],
919 loop_nr_contig_chunks *
920 sizeof(*window->num_pages));
921 }
922 }
923 remaining_nr_contig_chunks -= loop_nr_contig_chunks;
924 i += loop_nr_contig_chunks;
925 j++;
926 scif_iounmap(tmp, loop_nr_contig_chunks *
927 sizeof(*window->dma_addr), ep->remote_dev);
928 scif_iounmap(tmp1, loop_nr_contig_chunks *
929 sizeof(*window->num_pages), ep->remote_dev);
930 }
931
932 /* Prepare the remote window for the peer */
933 remote_window->peer_window = (u64)window;
934 remote_window->offset = window->offset;
935 remote_window->prot = window->prot;
936 remote_window->nr_contig_chunks = nr_contig_chunks;
937 remote_window->ep = ep->remote_ep;
938 scif_iounmap(num_pages_lookup,
939 nr_lookup *
940 sizeof(*remote_window->num_pages_lookup.lookup),
941 ep->remote_dev);
942 scif_iounmap(dma_phys_lookup,
943 nr_lookup *
944 sizeof(*remote_window->dma_addr_lookup.lookup),
945 ep->remote_dev);
946 scif_iounmap(remote_window, sizeof(*remote_window), ep->remote_dev);
947 window->peer_window = alloc->vaddr;
948 return err;
949 }
950
951 /**
952 * scif_send_scif_register:
953 * @ep: end point
954 * @window: self registration window
955 *
956 * Send a SCIF_REGISTER message if EP is connected and wait for a
957 * SCIF_REGISTER_(N)ACK message else send a SCIF_FREE_VIRT
958 * message so that the peer can free its remote window allocated earlier.
959 */
scif_send_scif_register(struct scif_endpt * ep,struct scif_window * window)960 static int scif_send_scif_register(struct scif_endpt *ep,
961 struct scif_window *window)
962 {
963 int err = 0;
964 struct scifmsg msg;
965
966 msg.src = ep->port;
967 msg.payload[0] = ep->remote_ep;
968 msg.payload[1] = window->alloc_handle.vaddr;
969 msg.payload[2] = (u64)window;
970 spin_lock(&ep->lock);
971 if (ep->state == SCIFEP_CONNECTED) {
972 msg.uop = SCIF_REGISTER;
973 window->reg_state = OP_IN_PROGRESS;
974 err = _scif_nodeqp_send(ep->remote_dev, &msg);
975 spin_unlock(&ep->lock);
976 if (!err) {
977 retry:
978 /* Wait for a SCIF_REGISTER_(N)ACK message */
979 err = wait_event_timeout(window->regwq,
980 window->reg_state !=
981 OP_IN_PROGRESS,
982 SCIF_NODE_ALIVE_TIMEOUT);
983 if (!err && scifdev_alive(ep))
984 goto retry;
985 err = !err ? -ENODEV : 0;
986 if (window->reg_state == OP_FAILED)
987 err = -ENOTCONN;
988 }
989 } else {
990 msg.uop = SCIF_FREE_VIRT;
991 msg.payload[3] = SCIF_REGISTER;
992 err = _scif_nodeqp_send(ep->remote_dev, &msg);
993 spin_unlock(&ep->lock);
994 if (!err)
995 err = -ENOTCONN;
996 }
997 return err;
998 }
999
1000 /**
1001 * scif_get_window_offset:
1002 * @ep: end point descriptor
1003 * @flags: flags
1004 * @offset: offset hint
1005 * @num_pages: number of pages
1006 * @out_offset: computed offset returned by reference.
1007 *
1008 * Compute/Claim a new offset for this EP.
1009 */
scif_get_window_offset(struct scif_endpt * ep,int flags,s64 offset,int num_pages,s64 * out_offset)1010 int scif_get_window_offset(struct scif_endpt *ep, int flags, s64 offset,
1011 int num_pages, s64 *out_offset)
1012 {
1013 s64 page_index;
1014 struct iova *iova_ptr;
1015 int err = 0;
1016
1017 if (flags & SCIF_MAP_FIXED) {
1018 page_index = SCIF_IOVA_PFN(offset);
1019 iova_ptr = reserve_iova(&ep->rma_info.iovad, page_index,
1020 page_index + num_pages - 1);
1021 if (!iova_ptr)
1022 err = -EADDRINUSE;
1023 } else {
1024 iova_ptr = alloc_iova(&ep->rma_info.iovad, num_pages,
1025 SCIF_DMA_63BIT_PFN - 1, 0);
1026 if (!iova_ptr)
1027 err = -ENOMEM;
1028 }
1029 if (!err)
1030 *out_offset = (iova_ptr->pfn_lo) << PAGE_SHIFT;
1031 return err;
1032 }
1033
1034 /**
1035 * scif_free_window_offset:
1036 * @ep: end point descriptor
1037 * @window: registration window
1038 * @offset: Offset to be freed
1039 *
1040 * Free offset for this EP. The callee is supposed to grab
1041 * the RMA mutex before calling this API.
1042 */
scif_free_window_offset(struct scif_endpt * ep,struct scif_window * window,s64 offset)1043 void scif_free_window_offset(struct scif_endpt *ep,
1044 struct scif_window *window, s64 offset)
1045 {
1046 if ((window && !window->offset_freed) || !window) {
1047 free_iova(&ep->rma_info.iovad, offset >> PAGE_SHIFT);
1048 if (window)
1049 window->offset_freed = true;
1050 }
1051 }
1052
1053 /**
1054 * scif_alloc_req: Respond to SCIF_ALLOC_REQ interrupt message
1055 * @msg: Interrupt message
1056 *
1057 * Remote side is requesting a memory allocation.
1058 */
scif_alloc_req(struct scif_dev * scifdev,struct scifmsg * msg)1059 void scif_alloc_req(struct scif_dev *scifdev, struct scifmsg *msg)
1060 {
1061 int err;
1062 struct scif_window *window = NULL;
1063 int nr_pages = msg->payload[1];
1064
1065 window = scif_create_remote_window(scifdev, nr_pages);
1066 if (!window) {
1067 err = -ENOMEM;
1068 goto error;
1069 }
1070
1071 /* The peer's allocation request is granted */
1072 msg->uop = SCIF_ALLOC_GNT;
1073 msg->payload[0] = (u64)window;
1074 msg->payload[1] = window->mapped_offset;
1075 err = scif_nodeqp_send(scifdev, msg);
1076 if (err)
1077 scif_destroy_remote_window(window);
1078 return;
1079 error:
1080 /* The peer's allocation request is rejected */
1081 dev_err(&scifdev->sdev->dev,
1082 "%s %d error %d alloc_ptr %p nr_pages 0x%x\n",
1083 __func__, __LINE__, err, window, nr_pages);
1084 msg->uop = SCIF_ALLOC_REJ;
1085 scif_nodeqp_send(scifdev, msg);
1086 }
1087
1088 /**
1089 * scif_alloc_gnt_rej: Respond to SCIF_ALLOC_GNT/REJ interrupt message
1090 * @msg: Interrupt message
1091 *
1092 * Remote side responded to a memory allocation.
1093 */
scif_alloc_gnt_rej(struct scif_dev * scifdev,struct scifmsg * msg)1094 void scif_alloc_gnt_rej(struct scif_dev *scifdev, struct scifmsg *msg)
1095 {
1096 struct scif_allocmsg *handle = (struct scif_allocmsg *)msg->payload[2];
1097 struct scif_window *window = container_of(handle, struct scif_window,
1098 alloc_handle);
1099 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1100
1101 mutex_lock(&ep->rma_info.rma_lock);
1102 handle->vaddr = msg->payload[0];
1103 handle->phys_addr = msg->payload[1];
1104 if (msg->uop == SCIF_ALLOC_GNT)
1105 handle->state = OP_COMPLETED;
1106 else
1107 handle->state = OP_FAILED;
1108 wake_up(&handle->allocwq);
1109 mutex_unlock(&ep->rma_info.rma_lock);
1110 }
1111
1112 /**
1113 * scif_free_virt: Respond to SCIF_FREE_VIRT interrupt message
1114 * @msg: Interrupt message
1115 *
1116 * Free up memory kmalloc'd earlier.
1117 */
scif_free_virt(struct scif_dev * scifdev,struct scifmsg * msg)1118 void scif_free_virt(struct scif_dev *scifdev, struct scifmsg *msg)
1119 {
1120 struct scif_window *window = (struct scif_window *)msg->payload[1];
1121
1122 scif_destroy_remote_window(window);
1123 }
1124
1125 static void
scif_fixup_aper_base(struct scif_dev * dev,struct scif_window * window)1126 scif_fixup_aper_base(struct scif_dev *dev, struct scif_window *window)
1127 {
1128 int j;
1129 struct scif_hw_dev *sdev = dev->sdev;
1130 phys_addr_t apt_base = 0;
1131
1132 /*
1133 * Add the aperture base if the DMA address is not card relative
1134 * since the DMA addresses need to be an offset into the bar
1135 */
1136 if (!scifdev_self(dev) && window->type == SCIF_WINDOW_PEER &&
1137 sdev->aper && !sdev->card_rel_da)
1138 apt_base = sdev->aper->pa;
1139 else
1140 return;
1141
1142 for (j = 0; j < window->nr_contig_chunks; j++) {
1143 if (window->num_pages[j])
1144 window->dma_addr[j] += apt_base;
1145 else
1146 break;
1147 }
1148 }
1149
1150 /**
1151 * scif_recv_reg: Respond to SCIF_REGISTER interrupt message
1152 * @msg: Interrupt message
1153 *
1154 * Update remote window list with a new registered window.
1155 */
scif_recv_reg(struct scif_dev * scifdev,struct scifmsg * msg)1156 void scif_recv_reg(struct scif_dev *scifdev, struct scifmsg *msg)
1157 {
1158 struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
1159 struct scif_window *window =
1160 (struct scif_window *)msg->payload[1];
1161
1162 mutex_lock(&ep->rma_info.rma_lock);
1163 spin_lock(&ep->lock);
1164 if (ep->state == SCIFEP_CONNECTED) {
1165 msg->uop = SCIF_REGISTER_ACK;
1166 scif_nodeqp_send(ep->remote_dev, msg);
1167 scif_fixup_aper_base(ep->remote_dev, window);
1168 /* No further failures expected. Insert new window */
1169 scif_insert_window(window, &ep->rma_info.remote_reg_list);
1170 } else {
1171 msg->uop = SCIF_REGISTER_NACK;
1172 scif_nodeqp_send(ep->remote_dev, msg);
1173 }
1174 spin_unlock(&ep->lock);
1175 mutex_unlock(&ep->rma_info.rma_lock);
1176 /* free up any lookup resources now that page lists are transferred */
1177 scif_destroy_remote_lookup(ep->remote_dev, window);
1178 /*
1179 * We could not insert the window but we need to
1180 * destroy the window.
1181 */
1182 if (msg->uop == SCIF_REGISTER_NACK)
1183 scif_destroy_remote_window(window);
1184 }
1185
1186 /**
1187 * scif_recv_unreg: Respond to SCIF_UNREGISTER interrupt message
1188 * @msg: Interrupt message
1189 *
1190 * Remove window from remote registration list;
1191 */
scif_recv_unreg(struct scif_dev * scifdev,struct scifmsg * msg)1192 void scif_recv_unreg(struct scif_dev *scifdev, struct scifmsg *msg)
1193 {
1194 struct scif_rma_req req;
1195 struct scif_window *window = NULL;
1196 struct scif_window *recv_window =
1197 (struct scif_window *)msg->payload[0];
1198 struct scif_endpt *ep;
1199 int del_window = 0;
1200
1201 ep = (struct scif_endpt *)recv_window->ep;
1202 req.out_window = &window;
1203 req.offset = recv_window->offset;
1204 req.prot = 0;
1205 req.nr_bytes = recv_window->nr_pages << PAGE_SHIFT;
1206 req.type = SCIF_WINDOW_FULL;
1207 req.head = &ep->rma_info.remote_reg_list;
1208 msg->payload[0] = ep->remote_ep;
1209
1210 mutex_lock(&ep->rma_info.rma_lock);
1211 /* Does a valid window exist? */
1212 if (scif_query_window(&req)) {
1213 dev_err(&scifdev->sdev->dev,
1214 "%s %d -ENXIO\n", __func__, __LINE__);
1215 msg->uop = SCIF_UNREGISTER_ACK;
1216 goto error;
1217 }
1218 if (window) {
1219 if (window->ref_count)
1220 scif_put_window(window, window->nr_pages);
1221 else
1222 dev_err(&scifdev->sdev->dev,
1223 "%s %d ref count should be +ve\n",
1224 __func__, __LINE__);
1225 window->unreg_state = OP_COMPLETED;
1226 if (!window->ref_count) {
1227 msg->uop = SCIF_UNREGISTER_ACK;
1228 atomic_inc(&ep->rma_info.tw_refcount);
1229 ep->rma_info.async_list_del = 1;
1230 list_del_init(&window->list);
1231 del_window = 1;
1232 } else {
1233 /* NACK! There are valid references to this window */
1234 msg->uop = SCIF_UNREGISTER_NACK;
1235 }
1236 } else {
1237 /* The window did not make its way to the list at all. ACK */
1238 msg->uop = SCIF_UNREGISTER_ACK;
1239 scif_destroy_remote_window(recv_window);
1240 }
1241 error:
1242 mutex_unlock(&ep->rma_info.rma_lock);
1243 if (del_window)
1244 scif_drain_dma_intr(ep->remote_dev->sdev,
1245 ep->rma_info.dma_chan);
1246 scif_nodeqp_send(ep->remote_dev, msg);
1247 if (del_window)
1248 scif_queue_for_cleanup(window, &scif_info.rma);
1249 }
1250
1251 /**
1252 * scif_recv_reg_ack: Respond to SCIF_REGISTER_ACK interrupt message
1253 * @msg: Interrupt message
1254 *
1255 * Wake up the window waiting to complete registration.
1256 */
scif_recv_reg_ack(struct scif_dev * scifdev,struct scifmsg * msg)1257 void scif_recv_reg_ack(struct scif_dev *scifdev, struct scifmsg *msg)
1258 {
1259 struct scif_window *window =
1260 (struct scif_window *)msg->payload[2];
1261 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1262
1263 mutex_lock(&ep->rma_info.rma_lock);
1264 window->reg_state = OP_COMPLETED;
1265 wake_up(&window->regwq);
1266 mutex_unlock(&ep->rma_info.rma_lock);
1267 }
1268
1269 /**
1270 * scif_recv_reg_nack: Respond to SCIF_REGISTER_NACK interrupt message
1271 * @msg: Interrupt message
1272 *
1273 * Wake up the window waiting to inform it that registration
1274 * cannot be completed.
1275 */
scif_recv_reg_nack(struct scif_dev * scifdev,struct scifmsg * msg)1276 void scif_recv_reg_nack(struct scif_dev *scifdev, struct scifmsg *msg)
1277 {
1278 struct scif_window *window =
1279 (struct scif_window *)msg->payload[2];
1280 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1281
1282 mutex_lock(&ep->rma_info.rma_lock);
1283 window->reg_state = OP_FAILED;
1284 wake_up(&window->regwq);
1285 mutex_unlock(&ep->rma_info.rma_lock);
1286 }
1287
1288 /**
1289 * scif_recv_unreg_ack: Respond to SCIF_UNREGISTER_ACK interrupt message
1290 * @msg: Interrupt message
1291 *
1292 * Wake up the window waiting to complete unregistration.
1293 */
scif_recv_unreg_ack(struct scif_dev * scifdev,struct scifmsg * msg)1294 void scif_recv_unreg_ack(struct scif_dev *scifdev, struct scifmsg *msg)
1295 {
1296 struct scif_window *window =
1297 (struct scif_window *)msg->payload[1];
1298 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1299
1300 mutex_lock(&ep->rma_info.rma_lock);
1301 window->unreg_state = OP_COMPLETED;
1302 wake_up(&window->unregwq);
1303 mutex_unlock(&ep->rma_info.rma_lock);
1304 }
1305
1306 /**
1307 * scif_recv_unreg_nack: Respond to SCIF_UNREGISTER_NACK interrupt message
1308 * @msg: Interrupt message
1309 *
1310 * Wake up the window waiting to inform it that unregistration
1311 * cannot be completed immediately.
1312 */
scif_recv_unreg_nack(struct scif_dev * scifdev,struct scifmsg * msg)1313 void scif_recv_unreg_nack(struct scif_dev *scifdev, struct scifmsg *msg)
1314 {
1315 struct scif_window *window =
1316 (struct scif_window *)msg->payload[1];
1317 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1318
1319 mutex_lock(&ep->rma_info.rma_lock);
1320 window->unreg_state = OP_FAILED;
1321 wake_up(&window->unregwq);
1322 mutex_unlock(&ep->rma_info.rma_lock);
1323 }
1324
__scif_pin_pages(void * addr,size_t len,int * out_prot,int map_flags,scif_pinned_pages_t * pages)1325 int __scif_pin_pages(void *addr, size_t len, int *out_prot,
1326 int map_flags, scif_pinned_pages_t *pages)
1327 {
1328 struct scif_pinned_pages *pinned_pages;
1329 int nr_pages, err = 0, i;
1330 bool vmalloc_addr = false;
1331 bool try_upgrade = false;
1332 int prot = *out_prot;
1333 int ulimit = 0;
1334 struct mm_struct *mm = NULL;
1335
1336 /* Unsupported flags */
1337 if (map_flags & ~(SCIF_MAP_KERNEL | SCIF_MAP_ULIMIT))
1338 return -EINVAL;
1339 ulimit = !!(map_flags & SCIF_MAP_ULIMIT);
1340
1341 /* Unsupported protection requested */
1342 if (prot & ~(SCIF_PROT_READ | SCIF_PROT_WRITE))
1343 return -EINVAL;
1344
1345 /* addr/len must be page aligned. len should be non zero */
1346 if (!len ||
1347 (ALIGN((u64)addr, PAGE_SIZE) != (u64)addr) ||
1348 (ALIGN((u64)len, PAGE_SIZE) != (u64)len))
1349 return -EINVAL;
1350
1351 might_sleep();
1352
1353 nr_pages = len >> PAGE_SHIFT;
1354
1355 /* Allocate a set of pinned pages */
1356 pinned_pages = scif_create_pinned_pages(nr_pages, prot);
1357 if (!pinned_pages)
1358 return -ENOMEM;
1359
1360 if (map_flags & SCIF_MAP_KERNEL) {
1361 if (is_vmalloc_addr(addr))
1362 vmalloc_addr = true;
1363
1364 for (i = 0; i < nr_pages; i++) {
1365 if (vmalloc_addr)
1366 pinned_pages->pages[i] =
1367 vmalloc_to_page(addr + (i * PAGE_SIZE));
1368 else
1369 pinned_pages->pages[i] =
1370 virt_to_page(addr + (i * PAGE_SIZE));
1371 }
1372 pinned_pages->nr_pages = nr_pages;
1373 pinned_pages->map_flags = SCIF_MAP_KERNEL;
1374 } else {
1375 /*
1376 * SCIF supports registration caching. If a registration has
1377 * been requested with read only permissions, then we try
1378 * to pin the pages with RW permissions so that a subsequent
1379 * transfer with RW permission can hit the cache instead of
1380 * invalidating it. If the upgrade fails with RW then we
1381 * revert back to R permission and retry
1382 */
1383 if (prot == SCIF_PROT_READ)
1384 try_upgrade = true;
1385 prot |= SCIF_PROT_WRITE;
1386 retry:
1387 mm = current->mm;
1388 down_write(&mm->mmap_sem);
1389 if (ulimit) {
1390 err = __scif_check_inc_pinned_vm(mm, nr_pages);
1391 if (err) {
1392 up_write(&mm->mmap_sem);
1393 pinned_pages->nr_pages = 0;
1394 goto error_unmap;
1395 }
1396 }
1397
1398 pinned_pages->nr_pages = get_user_pages(
1399 (u64)addr,
1400 nr_pages,
1401 (prot & SCIF_PROT_WRITE) ? FOLL_WRITE : 0,
1402 pinned_pages->pages,
1403 NULL);
1404 up_write(&mm->mmap_sem);
1405 if (nr_pages != pinned_pages->nr_pages) {
1406 if (pinned_pages->nr_pages < 0)
1407 pinned_pages->nr_pages = 0;
1408 if (try_upgrade) {
1409 if (ulimit)
1410 __scif_dec_pinned_vm_lock(mm,
1411 nr_pages, 0);
1412 /* Roll back any pinned pages */
1413 for (i = 0; i < pinned_pages->nr_pages; i++) {
1414 if (pinned_pages->pages[i])
1415 put_page(
1416 pinned_pages->pages[i]);
1417 }
1418 prot &= ~SCIF_PROT_WRITE;
1419 try_upgrade = false;
1420 goto retry;
1421 }
1422 }
1423 pinned_pages->map_flags = 0;
1424 }
1425
1426 if (pinned_pages->nr_pages < nr_pages) {
1427 err = -EFAULT;
1428 goto dec_pinned;
1429 }
1430
1431 *out_prot = prot;
1432 atomic_set(&pinned_pages->ref_count, 1);
1433 *pages = pinned_pages;
1434 return err;
1435 dec_pinned:
1436 if (ulimit)
1437 __scif_dec_pinned_vm_lock(mm, nr_pages, 0);
1438 /* Something went wrong! Rollback */
1439 error_unmap:
1440 scif_destroy_pinned_pages(pinned_pages);
1441 *pages = NULL;
1442 dev_dbg(scif_info.mdev.this_device,
1443 "%s %d err %d len 0x%lx\n", __func__, __LINE__, err, len);
1444 return err;
1445 }
1446
scif_pin_pages(void * addr,size_t len,int prot,int map_flags,scif_pinned_pages_t * pages)1447 int scif_pin_pages(void *addr, size_t len, int prot,
1448 int map_flags, scif_pinned_pages_t *pages)
1449 {
1450 return __scif_pin_pages(addr, len, &prot, map_flags, pages);
1451 }
1452 EXPORT_SYMBOL_GPL(scif_pin_pages);
1453
scif_unpin_pages(scif_pinned_pages_t pinned_pages)1454 int scif_unpin_pages(scif_pinned_pages_t pinned_pages)
1455 {
1456 int err = 0, ret;
1457
1458 if (!pinned_pages || SCIFEP_MAGIC != pinned_pages->magic)
1459 return -EINVAL;
1460
1461 ret = atomic_sub_return(1, &pinned_pages->ref_count);
1462 if (ret < 0) {
1463 dev_err(scif_info.mdev.this_device,
1464 "%s %d scif_unpin_pages called without pinning? rc %d\n",
1465 __func__, __LINE__, ret);
1466 return -EINVAL;
1467 }
1468 /*
1469 * Destroy the window if the ref count for this set of pinned
1470 * pages has dropped to zero. If it is positive then there is
1471 * a valid registered window which is backed by these pages and
1472 * it will be destroyed once all such windows are unregistered.
1473 */
1474 if (!ret)
1475 err = scif_destroy_pinned_pages(pinned_pages);
1476
1477 return err;
1478 }
1479 EXPORT_SYMBOL_GPL(scif_unpin_pages);
1480
1481 static inline void
scif_insert_local_window(struct scif_window * window,struct scif_endpt * ep)1482 scif_insert_local_window(struct scif_window *window, struct scif_endpt *ep)
1483 {
1484 mutex_lock(&ep->rma_info.rma_lock);
1485 scif_insert_window(window, &ep->rma_info.reg_list);
1486 mutex_unlock(&ep->rma_info.rma_lock);
1487 }
1488
scif_register_pinned_pages(scif_epd_t epd,scif_pinned_pages_t pinned_pages,off_t offset,int map_flags)1489 off_t scif_register_pinned_pages(scif_epd_t epd,
1490 scif_pinned_pages_t pinned_pages,
1491 off_t offset, int map_flags)
1492 {
1493 struct scif_endpt *ep = (struct scif_endpt *)epd;
1494 s64 computed_offset;
1495 struct scif_window *window;
1496 int err;
1497 size_t len;
1498 struct device *spdev;
1499
1500 /* Unsupported flags */
1501 if (map_flags & ~SCIF_MAP_FIXED)
1502 return -EINVAL;
1503
1504 len = pinned_pages->nr_pages << PAGE_SHIFT;
1505
1506 /*
1507 * Offset is not page aligned/negative or offset+len
1508 * wraps around with SCIF_MAP_FIXED.
1509 */
1510 if ((map_flags & SCIF_MAP_FIXED) &&
1511 ((ALIGN(offset, PAGE_SIZE) != offset) ||
1512 (offset < 0) ||
1513 (len > LONG_MAX - offset)))
1514 return -EINVAL;
1515
1516 might_sleep();
1517
1518 err = scif_verify_epd(ep);
1519 if (err)
1520 return err;
1521 /*
1522 * It is an error to pass pinned_pages to scif_register_pinned_pages()
1523 * after calling scif_unpin_pages().
1524 */
1525 if (!atomic_add_unless(&pinned_pages->ref_count, 1, 0))
1526 return -EINVAL;
1527
1528 /* Compute the offset for this registration */
1529 err = scif_get_window_offset(ep, map_flags, offset,
1530 len, &computed_offset);
1531 if (err) {
1532 atomic_sub(1, &pinned_pages->ref_count);
1533 return err;
1534 }
1535
1536 /* Allocate and prepare self registration window */
1537 window = scif_create_window(ep, pinned_pages->nr_pages,
1538 computed_offset, false);
1539 if (!window) {
1540 atomic_sub(1, &pinned_pages->ref_count);
1541 scif_free_window_offset(ep, NULL, computed_offset);
1542 return -ENOMEM;
1543 }
1544
1545 window->pinned_pages = pinned_pages;
1546 window->nr_pages = pinned_pages->nr_pages;
1547 window->prot = pinned_pages->prot;
1548
1549 spdev = scif_get_peer_dev(ep->remote_dev);
1550 if (IS_ERR(spdev)) {
1551 err = PTR_ERR(spdev);
1552 scif_destroy_window(ep, window);
1553 return err;
1554 }
1555 err = scif_send_alloc_request(ep, window);
1556 if (err) {
1557 dev_err(&ep->remote_dev->sdev->dev,
1558 "%s %d err %d\n", __func__, __LINE__, err);
1559 goto error_unmap;
1560 }
1561
1562 /* Prepare the remote registration window */
1563 err = scif_prep_remote_window(ep, window);
1564 if (err) {
1565 dev_err(&ep->remote_dev->sdev->dev,
1566 "%s %d err %d\n", __func__, __LINE__, err);
1567 goto error_unmap;
1568 }
1569
1570 /* Tell the peer about the new window */
1571 err = scif_send_scif_register(ep, window);
1572 if (err) {
1573 dev_err(&ep->remote_dev->sdev->dev,
1574 "%s %d err %d\n", __func__, __LINE__, err);
1575 goto error_unmap;
1576 }
1577
1578 scif_put_peer_dev(spdev);
1579 /* No further failures expected. Insert new window */
1580 scif_insert_local_window(window, ep);
1581 return computed_offset;
1582 error_unmap:
1583 scif_destroy_window(ep, window);
1584 scif_put_peer_dev(spdev);
1585 dev_err(&ep->remote_dev->sdev->dev,
1586 "%s %d err %d\n", __func__, __LINE__, err);
1587 return err;
1588 }
1589 EXPORT_SYMBOL_GPL(scif_register_pinned_pages);
1590
scif_register(scif_epd_t epd,void * addr,size_t len,off_t offset,int prot,int map_flags)1591 off_t scif_register(scif_epd_t epd, void *addr, size_t len, off_t offset,
1592 int prot, int map_flags)
1593 {
1594 scif_pinned_pages_t pinned_pages;
1595 off_t err;
1596 struct scif_endpt *ep = (struct scif_endpt *)epd;
1597 s64 computed_offset;
1598 struct scif_window *window;
1599 struct mm_struct *mm = NULL;
1600 struct device *spdev;
1601
1602 dev_dbg(scif_info.mdev.this_device,
1603 "SCIFAPI register: ep %p addr %p len 0x%lx offset 0x%lx prot 0x%x map_flags 0x%x\n",
1604 epd, addr, len, offset, prot, map_flags);
1605 /* Unsupported flags */
1606 if (map_flags & ~(SCIF_MAP_FIXED | SCIF_MAP_KERNEL))
1607 return -EINVAL;
1608
1609 /*
1610 * Offset is not page aligned/negative or offset+len
1611 * wraps around with SCIF_MAP_FIXED.
1612 */
1613 if ((map_flags & SCIF_MAP_FIXED) &&
1614 ((ALIGN(offset, PAGE_SIZE) != offset) ||
1615 (offset < 0) ||
1616 (len > LONG_MAX - offset)))
1617 return -EINVAL;
1618
1619 /* Unsupported protection requested */
1620 if (prot & ~(SCIF_PROT_READ | SCIF_PROT_WRITE))
1621 return -EINVAL;
1622
1623 /* addr/len must be page aligned. len should be non zero */
1624 if (!len || (ALIGN((u64)addr, PAGE_SIZE) != (u64)addr) ||
1625 (ALIGN(len, PAGE_SIZE) != len))
1626 return -EINVAL;
1627
1628 might_sleep();
1629
1630 err = scif_verify_epd(ep);
1631 if (err)
1632 return err;
1633
1634 /* Compute the offset for this registration */
1635 err = scif_get_window_offset(ep, map_flags, offset,
1636 len >> PAGE_SHIFT, &computed_offset);
1637 if (err)
1638 return err;
1639
1640 spdev = scif_get_peer_dev(ep->remote_dev);
1641 if (IS_ERR(spdev)) {
1642 err = PTR_ERR(spdev);
1643 scif_free_window_offset(ep, NULL, computed_offset);
1644 return err;
1645 }
1646 /* Allocate and prepare self registration window */
1647 window = scif_create_window(ep, len >> PAGE_SHIFT,
1648 computed_offset, false);
1649 if (!window) {
1650 scif_free_window_offset(ep, NULL, computed_offset);
1651 scif_put_peer_dev(spdev);
1652 return -ENOMEM;
1653 }
1654
1655 window->nr_pages = len >> PAGE_SHIFT;
1656
1657 err = scif_send_alloc_request(ep, window);
1658 if (err) {
1659 scif_destroy_incomplete_window(ep, window);
1660 scif_put_peer_dev(spdev);
1661 return err;
1662 }
1663
1664 if (!(map_flags & SCIF_MAP_KERNEL)) {
1665 mm = __scif_acquire_mm();
1666 map_flags |= SCIF_MAP_ULIMIT;
1667 }
1668 /* Pin down the pages */
1669 err = __scif_pin_pages(addr, len, &prot,
1670 map_flags & (SCIF_MAP_KERNEL | SCIF_MAP_ULIMIT),
1671 &pinned_pages);
1672 if (err) {
1673 scif_destroy_incomplete_window(ep, window);
1674 __scif_release_mm(mm);
1675 goto error;
1676 }
1677
1678 window->pinned_pages = pinned_pages;
1679 window->prot = pinned_pages->prot;
1680 window->mm = mm;
1681
1682 /* Prepare the remote registration window */
1683 err = scif_prep_remote_window(ep, window);
1684 if (err) {
1685 dev_err(&ep->remote_dev->sdev->dev,
1686 "%s %d err %ld\n", __func__, __LINE__, err);
1687 goto error_unmap;
1688 }
1689
1690 /* Tell the peer about the new window */
1691 err = scif_send_scif_register(ep, window);
1692 if (err) {
1693 dev_err(&ep->remote_dev->sdev->dev,
1694 "%s %d err %ld\n", __func__, __LINE__, err);
1695 goto error_unmap;
1696 }
1697
1698 scif_put_peer_dev(spdev);
1699 /* No further failures expected. Insert new window */
1700 scif_insert_local_window(window, ep);
1701 dev_dbg(&ep->remote_dev->sdev->dev,
1702 "SCIFAPI register: ep %p addr %p len 0x%lx computed_offset 0x%llx\n",
1703 epd, addr, len, computed_offset);
1704 return computed_offset;
1705 error_unmap:
1706 scif_destroy_window(ep, window);
1707 error:
1708 scif_put_peer_dev(spdev);
1709 dev_err(&ep->remote_dev->sdev->dev,
1710 "%s %d err %ld\n", __func__, __LINE__, err);
1711 return err;
1712 }
1713 EXPORT_SYMBOL_GPL(scif_register);
1714
1715 int
scif_unregister(scif_epd_t epd,off_t offset,size_t len)1716 scif_unregister(scif_epd_t epd, off_t offset, size_t len)
1717 {
1718 struct scif_endpt *ep = (struct scif_endpt *)epd;
1719 struct scif_window *window = NULL;
1720 struct scif_rma_req req;
1721 int nr_pages, err;
1722 struct device *spdev;
1723
1724 dev_dbg(scif_info.mdev.this_device,
1725 "SCIFAPI unregister: ep %p offset 0x%lx len 0x%lx\n",
1726 ep, offset, len);
1727 /* len must be page aligned. len should be non zero */
1728 if (!len ||
1729 (ALIGN((u64)len, PAGE_SIZE) != (u64)len))
1730 return -EINVAL;
1731
1732 /* Offset is not page aligned or offset+len wraps around */
1733 if ((ALIGN(offset, PAGE_SIZE) != offset) ||
1734 (offset < 0) ||
1735 (len > LONG_MAX - offset))
1736 return -EINVAL;
1737
1738 err = scif_verify_epd(ep);
1739 if (err)
1740 return err;
1741
1742 might_sleep();
1743 nr_pages = len >> PAGE_SHIFT;
1744
1745 req.out_window = &window;
1746 req.offset = offset;
1747 req.prot = 0;
1748 req.nr_bytes = len;
1749 req.type = SCIF_WINDOW_FULL;
1750 req.head = &ep->rma_info.reg_list;
1751
1752 spdev = scif_get_peer_dev(ep->remote_dev);
1753 if (IS_ERR(spdev)) {
1754 err = PTR_ERR(spdev);
1755 return err;
1756 }
1757 mutex_lock(&ep->rma_info.rma_lock);
1758 /* Does a valid window exist? */
1759 err = scif_query_window(&req);
1760 if (err) {
1761 dev_err(&ep->remote_dev->sdev->dev,
1762 "%s %d err %d\n", __func__, __LINE__, err);
1763 goto error;
1764 }
1765 /* Unregister all the windows in this range */
1766 err = scif_rma_list_unregister(window, offset, nr_pages);
1767 if (err)
1768 dev_err(&ep->remote_dev->sdev->dev,
1769 "%s %d err %d\n", __func__, __LINE__, err);
1770 error:
1771 mutex_unlock(&ep->rma_info.rma_lock);
1772 scif_put_peer_dev(spdev);
1773 return err;
1774 }
1775 EXPORT_SYMBOL_GPL(scif_unregister);
1776