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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Intel MIC Platform Software Stack (MPSS)
4 *
5 * Copyright(c) 2015 Intel Corporation.
6 *
7 * Intel SCIF driver.
8 */
9#include <linux/intel-iommu.h>
10#include <linux/pagemap.h>
11#include <linux/sched/mm.h>
12#include <linux/sched/signal.h>
13
14#include "scif_main.h"
15#include "scif_map.h"
16
17/* Used to skip ulimit checks for registrations with SCIF_MAP_KERNEL flag */
18#define SCIF_MAP_ULIMIT 0x40
19
20bool scif_ulimit_check = 1;
21
22/**
23 * scif_rma_ep_init:
24 * @ep: end point
25 *
26 * Initialize RMA per EP data structures.
27 */
28void scif_rma_ep_init(struct scif_endpt *ep)
29{
30 struct scif_endpt_rma_info *rma = &ep->rma_info;
31
32 mutex_init(&rma->rma_lock);
33 init_iova_domain(&rma->iovad, PAGE_SIZE, SCIF_IOVA_START_PFN);
34 spin_lock_init(&rma->tc_lock);
35 mutex_init(&rma->mmn_lock);
36 INIT_LIST_HEAD(&rma->reg_list);
37 INIT_LIST_HEAD(&rma->remote_reg_list);
38 atomic_set(&rma->tw_refcount, 0);
39 atomic_set(&rma->tcw_refcount, 0);
40 atomic_set(&rma->tcw_total_pages, 0);
41 atomic_set(&rma->fence_refcount, 0);
42
43 rma->async_list_del = 0;
44 rma->dma_chan = NULL;
45 INIT_LIST_HEAD(&rma->mmn_list);
46 INIT_LIST_HEAD(&rma->vma_list);
47 init_waitqueue_head(&rma->markwq);
48}
49
50/**
51 * scif_rma_ep_can_uninit:
52 * @ep: end point
53 *
54 * Returns 1 if an endpoint can be uninitialized and 0 otherwise.
55 */
56int scif_rma_ep_can_uninit(struct scif_endpt *ep)
57{
58 int ret = 0;
59
60 mutex_lock(&ep->rma_info.rma_lock);
61 /* Destroy RMA Info only if both lists are empty */
62 if (list_empty(&ep->rma_info.reg_list) &&
63 list_empty(&ep->rma_info.remote_reg_list) &&
64 list_empty(&ep->rma_info.mmn_list) &&
65 !atomic_read(&ep->rma_info.tw_refcount) &&
66 !atomic_read(&ep->rma_info.tcw_refcount) &&
67 !atomic_read(&ep->rma_info.fence_refcount))
68 ret = 1;
69 mutex_unlock(&ep->rma_info.rma_lock);
70 return ret;
71}
72
73/**
74 * scif_create_pinned_pages:
75 * @nr_pages: number of pages in window
76 * @prot: read/write protection
77 *
78 * Allocate and prepare a set of pinned pages.
79 */
80static struct scif_pinned_pages *
81scif_create_pinned_pages(int nr_pages, int prot)
82{
83 struct scif_pinned_pages *pin;
84
85 might_sleep();
86 pin = scif_zalloc(sizeof(*pin));
87 if (!pin)
88 goto error;
89
90 pin->pages = scif_zalloc(nr_pages * sizeof(*pin->pages));
91 if (!pin->pages)
92 goto error_free_pinned_pages;
93
94 pin->prot = prot;
95 pin->magic = SCIFEP_MAGIC;
96 return pin;
97
98error_free_pinned_pages:
99 scif_free(pin, sizeof(*pin));
100error:
101 return NULL;
102}
103
104/**
105 * scif_destroy_pinned_pages:
106 * @pin: A set of pinned pages.
107 *
108 * Deallocate resources for pinned pages.
109 */
110static int scif_destroy_pinned_pages(struct scif_pinned_pages *pin)
111{
112 int j;
113 int writeable = pin->prot & SCIF_PROT_WRITE;
114 int kernel = SCIF_MAP_KERNEL & pin->map_flags;
115
116 if (kernel) {
117 for (j = 0; j < pin->nr_pages; j++) {
118 if (pin->pages[j] && !kernel) {
119 if (writeable)
120 set_page_dirty_lock(pin->pages[j]);
121 put_page(pin->pages[j]);
122 }
123 }
124 } else
125 unpin_user_pages_dirty_lock(pin->pages, pin->nr_pages,
126 writeable);
127 scif_free(pin->pages,
128 pin->nr_pages * sizeof(*pin->pages));
129 scif_free(pin, sizeof(*pin));
130 return 0;
131}
132
133/*
134 * scif_create_window:
135 * @ep: end point
136 * @nr_pages: number of pages
137 * @offset: registration offset
138 * @temp: true if a temporary window is being created
139 *
140 * Allocate and prepare a self registration window.
141 */
142struct scif_window *scif_create_window(struct scif_endpt *ep, int nr_pages,
143 s64 offset, bool temp)
144{
145 struct scif_window *window;
146
147 might_sleep();
148 window = scif_zalloc(sizeof(*window));
149 if (!window)
150 goto error;
151
152 window->dma_addr = scif_zalloc(nr_pages * sizeof(*window->dma_addr));
153 if (!window->dma_addr)
154 goto error_free_window;
155
156 window->num_pages = scif_zalloc(nr_pages * sizeof(*window->num_pages));
157 if (!window->num_pages)
158 goto error_free_window;
159
160 window->offset = offset;
161 window->ep = (u64)ep;
162 window->magic = SCIFEP_MAGIC;
163 window->reg_state = OP_IDLE;
164 init_waitqueue_head(&window->regwq);
165 window->unreg_state = OP_IDLE;
166 init_waitqueue_head(&window->unregwq);
167 INIT_LIST_HEAD(&window->list);
168 window->type = SCIF_WINDOW_SELF;
169 window->temp = temp;
170 return window;
171
172error_free_window:
173 scif_free(window->dma_addr,
174 nr_pages * sizeof(*window->dma_addr));
175 scif_free(window, sizeof(*window));
176error:
177 return NULL;
178}
179
180/**
181 * scif_destroy_incomplete_window:
182 * @ep: end point
183 * @window: registration window
184 *
185 * Deallocate resources for self window.
186 */
187static void scif_destroy_incomplete_window(struct scif_endpt *ep,
188 struct scif_window *window)
189{
190 int err;
191 int nr_pages = window->nr_pages;
192 struct scif_allocmsg *alloc = &window->alloc_handle;
193 struct scifmsg msg;
194
195retry:
196 /* Wait for a SCIF_ALLOC_GNT/REJ message */
197 err = wait_event_timeout(alloc->allocwq,
198 alloc->state != OP_IN_PROGRESS,
199 SCIF_NODE_ALIVE_TIMEOUT);
200 if (!err && scifdev_alive(ep))
201 goto retry;
202
203 mutex_lock(&ep->rma_info.rma_lock);
204 if (alloc->state == OP_COMPLETED) {
205 msg.uop = SCIF_FREE_VIRT;
206 msg.src = ep->port;
207 msg.payload[0] = ep->remote_ep;
208 msg.payload[1] = window->alloc_handle.vaddr;
209 msg.payload[2] = (u64)window;
210 msg.payload[3] = SCIF_REGISTER;
211 _scif_nodeqp_send(ep->remote_dev, &msg);
212 }
213 mutex_unlock(&ep->rma_info.rma_lock);
214
215 scif_free_window_offset(ep, window, window->offset);
216 scif_free(window->dma_addr, nr_pages * sizeof(*window->dma_addr));
217 scif_free(window->num_pages, nr_pages * sizeof(*window->num_pages));
218 scif_free(window, sizeof(*window));
219}
220
221/**
222 * scif_unmap_window:
223 * @remote_dev: SCIF remote device
224 * @window: registration window
225 *
226 * Delete any DMA mappings created for a registered self window
227 */
228void scif_unmap_window(struct scif_dev *remote_dev, struct scif_window *window)
229{
230 int j;
231
232 if (scif_is_iommu_enabled() && !scifdev_self(remote_dev)) {
233 if (window->st) {
234 dma_unmap_sg(&remote_dev->sdev->dev,
235 window->st->sgl, window->st->nents,
236 DMA_BIDIRECTIONAL);
237 sg_free_table(window->st);
238 kfree(window->st);
239 window->st = NULL;
240 }
241 } else {
242 for (j = 0; j < window->nr_contig_chunks; j++) {
243 if (window->dma_addr[j]) {
244 scif_unmap_single(window->dma_addr[j],
245 remote_dev,
246 window->num_pages[j] <<
247 PAGE_SHIFT);
248 window->dma_addr[j] = 0x0;
249 }
250 }
251 }
252}
253
254static inline struct mm_struct *__scif_acquire_mm(void)
255{
256 if (scif_ulimit_check)
257 return get_task_mm(current);
258 return NULL;
259}
260
261static inline void __scif_release_mm(struct mm_struct *mm)
262{
263 if (mm)
264 mmput(mm);
265}
266
267static inline int
268__scif_dec_pinned_vm_lock(struct mm_struct *mm,
269 int nr_pages)
270{
271 if (!mm || !nr_pages || !scif_ulimit_check)
272 return 0;
273
274 atomic64_sub(nr_pages, &mm->pinned_vm);
275 return 0;
276}
277
278static inline int __scif_check_inc_pinned_vm(struct mm_struct *mm,
279 int nr_pages)
280{
281 unsigned long locked, lock_limit;
282
283 if (!mm || !nr_pages || !scif_ulimit_check)
284 return 0;
285
286 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
287 locked = atomic64_add_return(nr_pages, &mm->pinned_vm);
288
289 if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
290 atomic64_sub(nr_pages, &mm->pinned_vm);
291 dev_err(scif_info.mdev.this_device,
292 "locked(%lu) > lock_limit(%lu)\n",
293 locked, lock_limit);
294 return -ENOMEM;
295 }
296 return 0;
297}
298
299/**
300 * scif_destroy_window:
301 * @ep: end point
302 * @window: registration window
303 *
304 * Deallocate resources for self window.
305 */
306int scif_destroy_window(struct scif_endpt *ep, struct scif_window *window)
307{
308 int j;
309 struct scif_pinned_pages *pinned_pages = window->pinned_pages;
310 int nr_pages = window->nr_pages;
311
312 might_sleep();
313 if (!window->temp && window->mm) {
314 __scif_dec_pinned_vm_lock(window->mm, window->nr_pages);
315 __scif_release_mm(window->mm);
316 window->mm = NULL;
317 }
318
319 scif_free_window_offset(ep, window, window->offset);
320 scif_unmap_window(ep->remote_dev, window);
321 /*
322 * Decrement references for this set of pinned pages from
323 * this window.
324 */
325 j = atomic_sub_return(1, &pinned_pages->ref_count);
326 if (j < 0)
327 dev_err(scif_info.mdev.this_device,
328 "%s %d incorrect ref count %d\n",
329 __func__, __LINE__, j);
330 /*
331 * If the ref count for pinned_pages is zero then someone
332 * has already called scif_unpin_pages() for it and we should
333 * destroy the page cache.
334 */
335 if (!j)
336 scif_destroy_pinned_pages(window->pinned_pages);
337 scif_free(window->dma_addr, nr_pages * sizeof(*window->dma_addr));
338 scif_free(window->num_pages, nr_pages * sizeof(*window->num_pages));
339 window->magic = 0;
340 scif_free(window, sizeof(*window));
341 return 0;
342}
343
344/**
345 * scif_create_remote_lookup:
346 * @remote_dev: SCIF remote device
347 * @window: remote window
348 *
349 * Allocate and prepare lookup entries for the remote
350 * end to copy over the physical addresses.
351 * Returns 0 on success and appropriate errno on failure.
352 */
353static int scif_create_remote_lookup(struct scif_dev *remote_dev,
354 struct scif_window *window)
355{
356 int i, j, err = 0;
357 int nr_pages = window->nr_pages;
358 bool vmalloc_dma_phys, vmalloc_num_pages;
359
360 might_sleep();
361 /* Map window */
362 err = scif_map_single(&window->mapped_offset,
363 window, remote_dev, sizeof(*window));
364 if (err)
365 goto error_window;
366
367 /* Compute the number of lookup entries. 21 == 2MB Shift */
368 window->nr_lookup = ALIGN(nr_pages * PAGE_SIZE,
369 ((2) * 1024 * 1024)) >> 21;
370
371 window->dma_addr_lookup.lookup =
372 scif_alloc_coherent(&window->dma_addr_lookup.offset,
373 remote_dev, window->nr_lookup *
374 sizeof(*window->dma_addr_lookup.lookup),
375 GFP_KERNEL | __GFP_ZERO);
376 if (!window->dma_addr_lookup.lookup) {
377 err = -ENOMEM;
378 goto error_window;
379 }
380
381 window->num_pages_lookup.lookup =
382 scif_alloc_coherent(&window->num_pages_lookup.offset,
383 remote_dev, window->nr_lookup *
384 sizeof(*window->num_pages_lookup.lookup),
385 GFP_KERNEL | __GFP_ZERO);
386 if (!window->num_pages_lookup.lookup) {
387 err = -ENOMEM;
388 goto error_window;
389 }
390
391 vmalloc_dma_phys = is_vmalloc_addr(&window->dma_addr[0]);
392 vmalloc_num_pages = is_vmalloc_addr(&window->num_pages[0]);
393
394 /* Now map each of the pages containing physical addresses */
395 for (i = 0, j = 0; i < nr_pages; i += SCIF_NR_ADDR_IN_PAGE, j++) {
396 err = scif_map_page(&window->dma_addr_lookup.lookup[j],
397 vmalloc_dma_phys ?
398 vmalloc_to_page(&window->dma_addr[i]) :
399 virt_to_page(&window->dma_addr[i]),
400 remote_dev);
401 if (err)
402 goto error_window;
403 err = scif_map_page(&window->num_pages_lookup.lookup[j],
404 vmalloc_num_pages ?
405 vmalloc_to_page(&window->num_pages[i]) :
406 virt_to_page(&window->num_pages[i]),
407 remote_dev);
408 if (err)
409 goto error_window;
410 }
411 return 0;
412error_window:
413 return err;
414}
415
416/**
417 * scif_destroy_remote_lookup:
418 * @remote_dev: SCIF remote device
419 * @window: remote window
420 *
421 * Destroy lookup entries used for the remote
422 * end to copy over the physical addresses.
423 */
424static void scif_destroy_remote_lookup(struct scif_dev *remote_dev,
425 struct scif_window *window)
426{
427 int i, j;
428
429 if (window->nr_lookup) {
430 struct scif_rma_lookup *lup = &window->dma_addr_lookup;
431 struct scif_rma_lookup *npup = &window->num_pages_lookup;
432
433 for (i = 0, j = 0; i < window->nr_pages;
434 i += SCIF_NR_ADDR_IN_PAGE, j++) {
435 if (lup->lookup && lup->lookup[j])
436 scif_unmap_single(lup->lookup[j],
437 remote_dev,
438 PAGE_SIZE);
439 if (npup->lookup && npup->lookup[j])
440 scif_unmap_single(npup->lookup[j],
441 remote_dev,
442 PAGE_SIZE);
443 }
444 if (lup->lookup)
445 scif_free_coherent(lup->lookup, lup->offset,
446 remote_dev, window->nr_lookup *
447 sizeof(*lup->lookup));
448 if (npup->lookup)
449 scif_free_coherent(npup->lookup, npup->offset,
450 remote_dev, window->nr_lookup *
451 sizeof(*npup->lookup));
452 if (window->mapped_offset)
453 scif_unmap_single(window->mapped_offset,
454 remote_dev, sizeof(*window));
455 window->nr_lookup = 0;
456 }
457}
458
459/**
460 * scif_create_remote_window:
461 * @scifdev: SCIF device
462 * @nr_pages: number of pages in window
463 *
464 * Allocate and prepare a remote registration window.
465 */
466static struct scif_window *
467scif_create_remote_window(struct scif_dev *scifdev, int nr_pages)
468{
469 struct scif_window *window;
470
471 might_sleep();
472 window = scif_zalloc(sizeof(*window));
473 if (!window)
474 goto error_ret;
475
476 window->magic = SCIFEP_MAGIC;
477 window->nr_pages = nr_pages;
478
479 window->dma_addr = scif_zalloc(nr_pages * sizeof(*window->dma_addr));
480 if (!window->dma_addr)
481 goto error_window;
482
483 window->num_pages = scif_zalloc(nr_pages *
484 sizeof(*window->num_pages));
485 if (!window->num_pages)
486 goto error_window;
487
488 if (scif_create_remote_lookup(scifdev, window))
489 goto error_window;
490
491 window->type = SCIF_WINDOW_PEER;
492 window->unreg_state = OP_IDLE;
493 INIT_LIST_HEAD(&window->list);
494 return window;
495error_window:
496 scif_destroy_remote_window(window);
497error_ret:
498 return NULL;
499}
500
501/**
502 * scif_destroy_remote_window:
503 * @window: remote registration window
504 *
505 * Deallocate resources for remote window.
506 */
507void
508scif_destroy_remote_window(struct scif_window *window)
509{
510 scif_free(window->dma_addr, window->nr_pages *
511 sizeof(*window->dma_addr));
512 scif_free(window->num_pages, window->nr_pages *
513 sizeof(*window->num_pages));
514 window->magic = 0;
515 scif_free(window, sizeof(*window));
516}
517
518/**
519 * scif_iommu_map: create DMA mappings if the IOMMU is enabled
520 * @remote_dev: SCIF remote device
521 * @window: remote registration window
522 *
523 * Map the physical pages using dma_map_sg(..) and then detect the number
524 * of contiguous DMA mappings allocated
525 */
526static int scif_iommu_map(struct scif_dev *remote_dev,
527 struct scif_window *window)
528{
529 struct scatterlist *sg;
530 int i, err;
531 scif_pinned_pages_t pin = window->pinned_pages;
532
533 window->st = kzalloc(sizeof(*window->st), GFP_KERNEL);
534 if (!window->st)
535 return -ENOMEM;
536
537 err = sg_alloc_table(window->st, window->nr_pages, GFP_KERNEL);
538 if (err)
539 return err;
540
541 for_each_sg(window->st->sgl, sg, window->st->nents, i)
542 sg_set_page(sg, pin->pages[i], PAGE_SIZE, 0x0);
543
544 err = dma_map_sg(&remote_dev->sdev->dev, window->st->sgl,
545 window->st->nents, DMA_BIDIRECTIONAL);
546 if (!err)
547 return -ENOMEM;
548 /* Detect contiguous ranges of DMA mappings */
549 sg = window->st->sgl;
550 for (i = 0; sg; i++) {
551 dma_addr_t last_da;
552
553 window->dma_addr[i] = sg_dma_address(sg);
554 window->num_pages[i] = sg_dma_len(sg) >> PAGE_SHIFT;
555 last_da = sg_dma_address(sg) + sg_dma_len(sg);
556 while ((sg = sg_next(sg)) && sg_dma_address(sg) == last_da) {
557 window->num_pages[i] +=
558 (sg_dma_len(sg) >> PAGE_SHIFT);
559 last_da = window->dma_addr[i] +
560 sg_dma_len(sg);
561 }
562 window->nr_contig_chunks++;
563 }
564 return 0;
565}
566
567/**
568 * scif_map_window:
569 * @remote_dev: SCIF remote device
570 * @window: self registration window
571 *
572 * Map pages of a window into the aperture/PCI.
573 * Also determine addresses required for DMA.
574 */
575int
576scif_map_window(struct scif_dev *remote_dev, struct scif_window *window)
577{
578 int i, j, k, err = 0, nr_contig_pages;
579 scif_pinned_pages_t pin;
580 phys_addr_t phys_prev, phys_curr;
581
582 might_sleep();
583
584 pin = window->pinned_pages;
585
586 if (intel_iommu_enabled && !scifdev_self(remote_dev))
587 return scif_iommu_map(remote_dev, window);
588
589 for (i = 0, j = 0; i < window->nr_pages; i += nr_contig_pages, j++) {
590 phys_prev = page_to_phys(pin->pages[i]);
591 nr_contig_pages = 1;
592
593 /* Detect physically contiguous chunks */
594 for (k = i + 1; k < window->nr_pages; k++) {
595 phys_curr = page_to_phys(pin->pages[k]);
596 if (phys_curr != (phys_prev + PAGE_SIZE))
597 break;
598 phys_prev = phys_curr;
599 nr_contig_pages++;
600 }
601 window->num_pages[j] = nr_contig_pages;
602 window->nr_contig_chunks++;
603 if (scif_is_mgmt_node()) {
604 /*
605 * Management node has to deal with SMPT on X100 and
606 * hence the DMA mapping is required
607 */
608 err = scif_map_single(&window->dma_addr[j],
609 phys_to_virt(page_to_phys(
610 pin->pages[i])),
611 remote_dev,
612 nr_contig_pages << PAGE_SHIFT);
613 if (err)
614 return err;
615 } else {
616 window->dma_addr[j] = page_to_phys(pin->pages[i]);
617 }
618 }
619 return err;
620}
621
622/**
623 * scif_send_scif_unregister:
624 * @ep: end point
625 * @window: self registration window
626 *
627 * Send a SCIF_UNREGISTER message.
628 */
629static int scif_send_scif_unregister(struct scif_endpt *ep,
630 struct scif_window *window)
631{
632 struct scifmsg msg;
633
634 msg.uop = SCIF_UNREGISTER;
635 msg.src = ep->port;
636 msg.payload[0] = window->alloc_handle.vaddr;
637 msg.payload[1] = (u64)window;
638 return scif_nodeqp_send(ep->remote_dev, &msg);
639}
640
641/**
642 * scif_unregister_window:
643 * @window: self registration window
644 *
645 * Send an unregistration request and wait for a response.
646 */
647int scif_unregister_window(struct scif_window *window)
648{
649 int err = 0;
650 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
651 bool send_msg = false;
652
653 might_sleep();
654 switch (window->unreg_state) {
655 case OP_IDLE:
656 {
657 window->unreg_state = OP_IN_PROGRESS;
658 send_msg = true;
659 }
660 fallthrough;
661 case OP_IN_PROGRESS:
662 {
663 scif_get_window(window, 1);
664 mutex_unlock(&ep->rma_info.rma_lock);
665 if (send_msg) {
666 err = scif_send_scif_unregister(ep, window);
667 if (err) {
668 window->unreg_state = OP_COMPLETED;
669 goto done;
670 }
671 } else {
672 /* Return ENXIO since unregistration is in progress */
673 mutex_lock(&ep->rma_info.rma_lock);
674 return -ENXIO;
675 }
676retry:
677 /* Wait for a SCIF_UNREGISTER_(N)ACK message */
678 err = wait_event_timeout(window->unregwq,
679 window->unreg_state != OP_IN_PROGRESS,
680 SCIF_NODE_ALIVE_TIMEOUT);
681 if (!err && scifdev_alive(ep))
682 goto retry;
683 if (!err) {
684 err = -ENODEV;
685 window->unreg_state = OP_COMPLETED;
686 dev_err(scif_info.mdev.this_device,
687 "%s %d err %d\n", __func__, __LINE__, err);
688 }
689 if (err > 0)
690 err = 0;
691done:
692 mutex_lock(&ep->rma_info.rma_lock);
693 scif_put_window(window, 1);
694 break;
695 }
696 case OP_FAILED:
697 {
698 if (!scifdev_alive(ep)) {
699 err = -ENODEV;
700 window->unreg_state = OP_COMPLETED;
701 }
702 break;
703 }
704 case OP_COMPLETED:
705 break;
706 default:
707 err = -ENODEV;
708 }
709
710 if (window->unreg_state == OP_COMPLETED && window->ref_count)
711 scif_put_window(window, window->nr_pages);
712
713 if (!window->ref_count) {
714 atomic_inc(&ep->rma_info.tw_refcount);
715 list_del_init(&window->list);
716 scif_free_window_offset(ep, window, window->offset);
717 mutex_unlock(&ep->rma_info.rma_lock);
718 if ((!!(window->pinned_pages->map_flags & SCIF_MAP_KERNEL)) &&
719 scifdev_alive(ep)) {
720 scif_drain_dma_intr(ep->remote_dev->sdev,
721 ep->rma_info.dma_chan);
722 } else {
723 if (!__scif_dec_pinned_vm_lock(window->mm,
724 window->nr_pages)) {
725 __scif_release_mm(window->mm);
726 window->mm = NULL;
727 }
728 }
729 scif_queue_for_cleanup(window, &scif_info.rma);
730 mutex_lock(&ep->rma_info.rma_lock);
731 }
732 return err;
733}
734
735/**
736 * scif_send_alloc_request:
737 * @ep: end point
738 * @window: self registration window
739 *
740 * Send a remote window allocation request
741 */
742static int scif_send_alloc_request(struct scif_endpt *ep,
743 struct scif_window *window)
744{
745 struct scifmsg msg;
746 struct scif_allocmsg *alloc = &window->alloc_handle;
747
748 /* Set up the Alloc Handle */
749 alloc->state = OP_IN_PROGRESS;
750 init_waitqueue_head(&alloc->allocwq);
751
752 /* Send out an allocation request */
753 msg.uop = SCIF_ALLOC_REQ;
754 msg.payload[1] = window->nr_pages;
755 msg.payload[2] = (u64)&window->alloc_handle;
756 return _scif_nodeqp_send(ep->remote_dev, &msg);
757}
758
759/**
760 * scif_prep_remote_window:
761 * @ep: end point
762 * @window: self registration window
763 *
764 * Send a remote window allocation request, wait for an allocation response,
765 * and prepares the remote window by copying over the page lists
766 */
767static int scif_prep_remote_window(struct scif_endpt *ep,
768 struct scif_window *window)
769{
770 struct scifmsg msg;
771 struct scif_window *remote_window;
772 struct scif_allocmsg *alloc = &window->alloc_handle;
773 dma_addr_t *dma_phys_lookup, *tmp, *num_pages_lookup, *tmp1;
774 int i = 0, j = 0;
775 int nr_contig_chunks, loop_nr_contig_chunks;
776 int remaining_nr_contig_chunks, nr_lookup;
777 int err, map_err;
778
779 map_err = scif_map_window(ep->remote_dev, window);
780 if (map_err)
781 dev_err(&ep->remote_dev->sdev->dev,
782 "%s %d map_err %d\n", __func__, __LINE__, map_err);
783 remaining_nr_contig_chunks = window->nr_contig_chunks;
784 nr_contig_chunks = window->nr_contig_chunks;
785retry:
786 /* Wait for a SCIF_ALLOC_GNT/REJ message */
787 err = wait_event_timeout(alloc->allocwq,
788 alloc->state != OP_IN_PROGRESS,
789 SCIF_NODE_ALIVE_TIMEOUT);
790 mutex_lock(&ep->rma_info.rma_lock);
791 /* Synchronize with the thread waking up allocwq */
792 mutex_unlock(&ep->rma_info.rma_lock);
793 if (!err && scifdev_alive(ep))
794 goto retry;
795
796 if (!err)
797 err = -ENODEV;
798
799 if (err > 0)
800 err = 0;
801 else
802 return err;
803
804 /* Bail out. The remote end rejected this request */
805 if (alloc->state == OP_FAILED)
806 return -ENOMEM;
807
808 if (map_err) {
809 dev_err(&ep->remote_dev->sdev->dev,
810 "%s %d err %d\n", __func__, __LINE__, map_err);
811 msg.uop = SCIF_FREE_VIRT;
812 msg.src = ep->port;
813 msg.payload[0] = ep->remote_ep;
814 msg.payload[1] = window->alloc_handle.vaddr;
815 msg.payload[2] = (u64)window;
816 msg.payload[3] = SCIF_REGISTER;
817 spin_lock(&ep->lock);
818 if (ep->state == SCIFEP_CONNECTED)
819 err = _scif_nodeqp_send(ep->remote_dev, &msg);
820 else
821 err = -ENOTCONN;
822 spin_unlock(&ep->lock);
823 return err;
824 }
825
826 remote_window = scif_ioremap(alloc->phys_addr, sizeof(*window),
827 ep->remote_dev);
828
829 /* Compute the number of lookup entries. 21 == 2MB Shift */
830 nr_lookup = ALIGN(nr_contig_chunks, SCIF_NR_ADDR_IN_PAGE)
831 >> ilog2(SCIF_NR_ADDR_IN_PAGE);
832
833 dma_phys_lookup =
834 scif_ioremap(remote_window->dma_addr_lookup.offset,
835 nr_lookup *
836 sizeof(*remote_window->dma_addr_lookup.lookup),
837 ep->remote_dev);
838 num_pages_lookup =
839 scif_ioremap(remote_window->num_pages_lookup.offset,
840 nr_lookup *
841 sizeof(*remote_window->num_pages_lookup.lookup),
842 ep->remote_dev);
843
844 while (remaining_nr_contig_chunks) {
845 loop_nr_contig_chunks = min_t(int, remaining_nr_contig_chunks,
846 (int)SCIF_NR_ADDR_IN_PAGE);
847 /* #1/2 - Copy physical addresses over to the remote side */
848
849 /* #2/2 - Copy DMA addresses (addresses that are fed into the
850 * DMA engine) We transfer bus addresses which are then
851 * converted into a MIC physical address on the remote
852 * side if it is a MIC, if the remote node is a mgmt node we
853 * transfer the MIC physical address
854 */
855 tmp = scif_ioremap(dma_phys_lookup[j],
856 loop_nr_contig_chunks *
857 sizeof(*window->dma_addr),
858 ep->remote_dev);
859 tmp1 = scif_ioremap(num_pages_lookup[j],
860 loop_nr_contig_chunks *
861 sizeof(*window->num_pages),
862 ep->remote_dev);
863 if (scif_is_mgmt_node()) {
864 memcpy_toio((void __force __iomem *)tmp,
865 &window->dma_addr[i], loop_nr_contig_chunks
866 * sizeof(*window->dma_addr));
867 memcpy_toio((void __force __iomem *)tmp1,
868 &window->num_pages[i], loop_nr_contig_chunks
869 * sizeof(*window->num_pages));
870 } else {
871 if (scifdev_is_p2p(ep->remote_dev)) {
872 /*
873 * add remote node's base address for this node
874 * to convert it into a MIC address
875 */
876 int m;
877 dma_addr_t dma_addr;
878
879 for (m = 0; m < loop_nr_contig_chunks; m++) {
880 dma_addr = window->dma_addr[i + m] +
881 ep->remote_dev->base_addr;
882 writeq(dma_addr,
883 (void __force __iomem *)&tmp[m]);
884 }
885 memcpy_toio((void __force __iomem *)tmp1,
886 &window->num_pages[i],
887 loop_nr_contig_chunks
888 * sizeof(*window->num_pages));
889 } else {
890 /* Mgmt node or loopback - transfer DMA
891 * addresses as is, this is the same as a
892 * MIC physical address (we use the dma_addr
893 * and not the phys_addr array since the
894 * phys_addr is only setup if there is a mmap()
895 * request from the mgmt node)
896 */
897 memcpy_toio((void __force __iomem *)tmp,
898 &window->dma_addr[i],
899 loop_nr_contig_chunks *
900 sizeof(*window->dma_addr));
901 memcpy_toio((void __force __iomem *)tmp1,
902 &window->num_pages[i],
903 loop_nr_contig_chunks *
904 sizeof(*window->num_pages));
905 }
906 }
907 remaining_nr_contig_chunks -= loop_nr_contig_chunks;
908 i += loop_nr_contig_chunks;
909 j++;
910 scif_iounmap(tmp, loop_nr_contig_chunks *
911 sizeof(*window->dma_addr), ep->remote_dev);
912 scif_iounmap(tmp1, loop_nr_contig_chunks *
913 sizeof(*window->num_pages), ep->remote_dev);
914 }
915
916 /* Prepare the remote window for the peer */
917 remote_window->peer_window = (u64)window;
918 remote_window->offset = window->offset;
919 remote_window->prot = window->prot;
920 remote_window->nr_contig_chunks = nr_contig_chunks;
921 remote_window->ep = ep->remote_ep;
922 scif_iounmap(num_pages_lookup,
923 nr_lookup *
924 sizeof(*remote_window->num_pages_lookup.lookup),
925 ep->remote_dev);
926 scif_iounmap(dma_phys_lookup,
927 nr_lookup *
928 sizeof(*remote_window->dma_addr_lookup.lookup),
929 ep->remote_dev);
930 scif_iounmap(remote_window, sizeof(*remote_window), ep->remote_dev);
931 window->peer_window = alloc->vaddr;
932 return err;
933}
934
935/**
936 * scif_send_scif_register:
937 * @ep: end point
938 * @window: self registration window
939 *
940 * Send a SCIF_REGISTER message if EP is connected and wait for a
941 * SCIF_REGISTER_(N)ACK message else send a SCIF_FREE_VIRT
942 * message so that the peer can free its remote window allocated earlier.
943 */
944static int scif_send_scif_register(struct scif_endpt *ep,
945 struct scif_window *window)
946{
947 int err = 0;
948 struct scifmsg msg;
949
950 msg.src = ep->port;
951 msg.payload[0] = ep->remote_ep;
952 msg.payload[1] = window->alloc_handle.vaddr;
953 msg.payload[2] = (u64)window;
954 spin_lock(&ep->lock);
955 if (ep->state == SCIFEP_CONNECTED) {
956 msg.uop = SCIF_REGISTER;
957 window->reg_state = OP_IN_PROGRESS;
958 err = _scif_nodeqp_send(ep->remote_dev, &msg);
959 spin_unlock(&ep->lock);
960 if (!err) {
961retry:
962 /* Wait for a SCIF_REGISTER_(N)ACK message */
963 err = wait_event_timeout(window->regwq,
964 window->reg_state !=
965 OP_IN_PROGRESS,
966 SCIF_NODE_ALIVE_TIMEOUT);
967 if (!err && scifdev_alive(ep))
968 goto retry;
969 err = !err ? -ENODEV : 0;
970 if (window->reg_state == OP_FAILED)
971 err = -ENOTCONN;
972 }
973 } else {
974 msg.uop = SCIF_FREE_VIRT;
975 msg.payload[3] = SCIF_REGISTER;
976 err = _scif_nodeqp_send(ep->remote_dev, &msg);
977 spin_unlock(&ep->lock);
978 if (!err)
979 err = -ENOTCONN;
980 }
981 return err;
982}
983
984/**
985 * scif_get_window_offset:
986 * @ep: end point descriptor
987 * @flags: flags
988 * @offset: offset hint
989 * @num_pages: number of pages
990 * @out_offset: computed offset returned by reference.
991 *
992 * Compute/Claim a new offset for this EP.
993 */
994int scif_get_window_offset(struct scif_endpt *ep, int flags, s64 offset,
995 int num_pages, s64 *out_offset)
996{
997 s64 page_index;
998 struct iova *iova_ptr;
999 int err = 0;
1000
1001 if (flags & SCIF_MAP_FIXED) {
1002 page_index = SCIF_IOVA_PFN(offset);
1003 iova_ptr = reserve_iova(&ep->rma_info.iovad, page_index,
1004 page_index + num_pages - 1);
1005 if (!iova_ptr)
1006 err = -EADDRINUSE;
1007 } else {
1008 iova_ptr = alloc_iova(&ep->rma_info.iovad, num_pages,
1009 SCIF_DMA_63BIT_PFN - 1, 0);
1010 if (!iova_ptr)
1011 err = -ENOMEM;
1012 }
1013 if (!err)
1014 *out_offset = (iova_ptr->pfn_lo) << PAGE_SHIFT;
1015 return err;
1016}
1017
1018/**
1019 * scif_free_window_offset:
1020 * @ep: end point descriptor
1021 * @window: registration window
1022 * @offset: Offset to be freed
1023 *
1024 * Free offset for this EP. The callee is supposed to grab
1025 * the RMA mutex before calling this API.
1026 */
1027void scif_free_window_offset(struct scif_endpt *ep,
1028 struct scif_window *window, s64 offset)
1029{
1030 if ((window && !window->offset_freed) || !window) {
1031 free_iova(&ep->rma_info.iovad, offset >> PAGE_SHIFT);
1032 if (window)
1033 window->offset_freed = true;
1034 }
1035}
1036
1037/**
1038 * scif_alloc_req: Respond to SCIF_ALLOC_REQ interrupt message
1039 * @scifdev: SCIF device
1040 * @msg: Interrupt message
1041 *
1042 * Remote side is requesting a memory allocation.
1043 */
1044void scif_alloc_req(struct scif_dev *scifdev, struct scifmsg *msg)
1045{
1046 int err;
1047 struct scif_window *window = NULL;
1048 int nr_pages = msg->payload[1];
1049
1050 window = scif_create_remote_window(scifdev, nr_pages);
1051 if (!window) {
1052 err = -ENOMEM;
1053 goto error;
1054 }
1055
1056 /* The peer's allocation request is granted */
1057 msg->uop = SCIF_ALLOC_GNT;
1058 msg->payload[0] = (u64)window;
1059 msg->payload[1] = window->mapped_offset;
1060 err = scif_nodeqp_send(scifdev, msg);
1061 if (err)
1062 scif_destroy_remote_window(window);
1063 return;
1064error:
1065 /* The peer's allocation request is rejected */
1066 dev_err(&scifdev->sdev->dev,
1067 "%s %d error %d alloc_ptr %p nr_pages 0x%x\n",
1068 __func__, __LINE__, err, window, nr_pages);
1069 msg->uop = SCIF_ALLOC_REJ;
1070 scif_nodeqp_send(scifdev, msg);
1071}
1072
1073/**
1074 * scif_alloc_gnt_rej: Respond to SCIF_ALLOC_GNT/REJ interrupt message
1075 * @scifdev: SCIF device
1076 * @msg: Interrupt message
1077 *
1078 * Remote side responded to a memory allocation.
1079 */
1080void scif_alloc_gnt_rej(struct scif_dev *scifdev, struct scifmsg *msg)
1081{
1082 struct scif_allocmsg *handle = (struct scif_allocmsg *)msg->payload[2];
1083 struct scif_window *window = container_of(handle, struct scif_window,
1084 alloc_handle);
1085 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1086
1087 mutex_lock(&ep->rma_info.rma_lock);
1088 handle->vaddr = msg->payload[0];
1089 handle->phys_addr = msg->payload[1];
1090 if (msg->uop == SCIF_ALLOC_GNT)
1091 handle->state = OP_COMPLETED;
1092 else
1093 handle->state = OP_FAILED;
1094 wake_up(&handle->allocwq);
1095 mutex_unlock(&ep->rma_info.rma_lock);
1096}
1097
1098/**
1099 * scif_free_virt: Respond to SCIF_FREE_VIRT interrupt message
1100 * @scifdev: SCIF device
1101 * @msg: Interrupt message
1102 *
1103 * Free up memory kmalloc'd earlier.
1104 */
1105void scif_free_virt(struct scif_dev *scifdev, struct scifmsg *msg)
1106{
1107 struct scif_window *window = (struct scif_window *)msg->payload[1];
1108
1109 scif_destroy_remote_window(window);
1110}
1111
1112static void
1113scif_fixup_aper_base(struct scif_dev *dev, struct scif_window *window)
1114{
1115 int j;
1116 struct scif_hw_dev *sdev = dev->sdev;
1117 phys_addr_t apt_base = 0;
1118
1119 /*
1120 * Add the aperture base if the DMA address is not card relative
1121 * since the DMA addresses need to be an offset into the bar
1122 */
1123 if (!scifdev_self(dev) && window->type == SCIF_WINDOW_PEER &&
1124 sdev->aper && !sdev->card_rel_da)
1125 apt_base = sdev->aper->pa;
1126 else
1127 return;
1128
1129 for (j = 0; j < window->nr_contig_chunks; j++) {
1130 if (window->num_pages[j])
1131 window->dma_addr[j] += apt_base;
1132 else
1133 break;
1134 }
1135}
1136
1137/**
1138 * scif_recv_reg: Respond to SCIF_REGISTER interrupt message
1139 * @scifdev: SCIF device
1140 * @msg: Interrupt message
1141 *
1142 * Update remote window list with a new registered window.
1143 */
1144void scif_recv_reg(struct scif_dev *scifdev, struct scifmsg *msg)
1145{
1146 struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
1147 struct scif_window *window =
1148 (struct scif_window *)msg->payload[1];
1149
1150 mutex_lock(&ep->rma_info.rma_lock);
1151 spin_lock(&ep->lock);
1152 if (ep->state == SCIFEP_CONNECTED) {
1153 msg->uop = SCIF_REGISTER_ACK;
1154 scif_nodeqp_send(ep->remote_dev, msg);
1155 scif_fixup_aper_base(ep->remote_dev, window);
1156 /* No further failures expected. Insert new window */
1157 scif_insert_window(window, &ep->rma_info.remote_reg_list);
1158 } else {
1159 msg->uop = SCIF_REGISTER_NACK;
1160 scif_nodeqp_send(ep->remote_dev, msg);
1161 }
1162 spin_unlock(&ep->lock);
1163 mutex_unlock(&ep->rma_info.rma_lock);
1164 /* free up any lookup resources now that page lists are transferred */
1165 scif_destroy_remote_lookup(ep->remote_dev, window);
1166 /*
1167 * We could not insert the window but we need to
1168 * destroy the window.
1169 */
1170 if (msg->uop == SCIF_REGISTER_NACK)
1171 scif_destroy_remote_window(window);
1172}
1173
1174/**
1175 * scif_recv_unreg: Respond to SCIF_UNREGISTER interrupt message
1176 * @scifdev: SCIF device
1177 * @msg: Interrupt message
1178 *
1179 * Remove window from remote registration list;
1180 */
1181void scif_recv_unreg(struct scif_dev *scifdev, struct scifmsg *msg)
1182{
1183 struct scif_rma_req req;
1184 struct scif_window *window = NULL;
1185 struct scif_window *recv_window =
1186 (struct scif_window *)msg->payload[0];
1187 struct scif_endpt *ep;
1188 int del_window = 0;
1189
1190 ep = (struct scif_endpt *)recv_window->ep;
1191 req.out_window = &window;
1192 req.offset = recv_window->offset;
1193 req.prot = 0;
1194 req.nr_bytes = recv_window->nr_pages << PAGE_SHIFT;
1195 req.type = SCIF_WINDOW_FULL;
1196 req.head = &ep->rma_info.remote_reg_list;
1197 msg->payload[0] = ep->remote_ep;
1198
1199 mutex_lock(&ep->rma_info.rma_lock);
1200 /* Does a valid window exist? */
1201 if (scif_query_window(&req)) {
1202 dev_err(&scifdev->sdev->dev,
1203 "%s %d -ENXIO\n", __func__, __LINE__);
1204 msg->uop = SCIF_UNREGISTER_ACK;
1205 goto error;
1206 }
1207 if (window) {
1208 if (window->ref_count)
1209 scif_put_window(window, window->nr_pages);
1210 else
1211 dev_err(&scifdev->sdev->dev,
1212 "%s %d ref count should be +ve\n",
1213 __func__, __LINE__);
1214 window->unreg_state = OP_COMPLETED;
1215 if (!window->ref_count) {
1216 msg->uop = SCIF_UNREGISTER_ACK;
1217 atomic_inc(&ep->rma_info.tw_refcount);
1218 ep->rma_info.async_list_del = 1;
1219 list_del_init(&window->list);
1220 del_window = 1;
1221 } else {
1222 /* NACK! There are valid references to this window */
1223 msg->uop = SCIF_UNREGISTER_NACK;
1224 }
1225 } else {
1226 /* The window did not make its way to the list at all. ACK */
1227 msg->uop = SCIF_UNREGISTER_ACK;
1228 scif_destroy_remote_window(recv_window);
1229 }
1230error:
1231 mutex_unlock(&ep->rma_info.rma_lock);
1232 if (del_window)
1233 scif_drain_dma_intr(ep->remote_dev->sdev,
1234 ep->rma_info.dma_chan);
1235 scif_nodeqp_send(ep->remote_dev, msg);
1236 if (del_window)
1237 scif_queue_for_cleanup(window, &scif_info.rma);
1238}
1239
1240/**
1241 * scif_recv_reg_ack: Respond to SCIF_REGISTER_ACK interrupt message
1242 * @scifdev: SCIF device
1243 * @msg: Interrupt message
1244 *
1245 * Wake up the window waiting to complete registration.
1246 */
1247void scif_recv_reg_ack(struct scif_dev *scifdev, struct scifmsg *msg)
1248{
1249 struct scif_window *window =
1250 (struct scif_window *)msg->payload[2];
1251 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1252
1253 mutex_lock(&ep->rma_info.rma_lock);
1254 window->reg_state = OP_COMPLETED;
1255 wake_up(&window->regwq);
1256 mutex_unlock(&ep->rma_info.rma_lock);
1257}
1258
1259/**
1260 * scif_recv_reg_nack: Respond to SCIF_REGISTER_NACK interrupt message
1261 * @scifdev: SCIF device
1262 * @msg: Interrupt message
1263 *
1264 * Wake up the window waiting to inform it that registration
1265 * cannot be completed.
1266 */
1267void scif_recv_reg_nack(struct scif_dev *scifdev, struct scifmsg *msg)
1268{
1269 struct scif_window *window =
1270 (struct scif_window *)msg->payload[2];
1271 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1272
1273 mutex_lock(&ep->rma_info.rma_lock);
1274 window->reg_state = OP_FAILED;
1275 wake_up(&window->regwq);
1276 mutex_unlock(&ep->rma_info.rma_lock);
1277}
1278
1279/**
1280 * scif_recv_unreg_ack: Respond to SCIF_UNREGISTER_ACK interrupt message
1281 * @scifdev: SCIF device
1282 * @msg: Interrupt message
1283 *
1284 * Wake up the window waiting to complete unregistration.
1285 */
1286void scif_recv_unreg_ack(struct scif_dev *scifdev, struct scifmsg *msg)
1287{
1288 struct scif_window *window =
1289 (struct scif_window *)msg->payload[1];
1290 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1291
1292 mutex_lock(&ep->rma_info.rma_lock);
1293 window->unreg_state = OP_COMPLETED;
1294 wake_up(&window->unregwq);
1295 mutex_unlock(&ep->rma_info.rma_lock);
1296}
1297
1298/**
1299 * scif_recv_unreg_nack: Respond to SCIF_UNREGISTER_NACK interrupt message
1300 * @scifdev: SCIF device
1301 * @msg: Interrupt message
1302 *
1303 * Wake up the window waiting to inform it that unregistration
1304 * cannot be completed immediately.
1305 */
1306void scif_recv_unreg_nack(struct scif_dev *scifdev, struct scifmsg *msg)
1307{
1308 struct scif_window *window =
1309 (struct scif_window *)msg->payload[1];
1310 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1311
1312 mutex_lock(&ep->rma_info.rma_lock);
1313 window->unreg_state = OP_FAILED;
1314 wake_up(&window->unregwq);
1315 mutex_unlock(&ep->rma_info.rma_lock);
1316}
1317
1318int __scif_pin_pages(void *addr, size_t len, int *out_prot,
1319 int map_flags, scif_pinned_pages_t *pages)
1320{
1321 struct scif_pinned_pages *pinned_pages;
1322 int nr_pages, err = 0, i;
1323 bool vmalloc_addr = false;
1324 bool try_upgrade = false;
1325 int prot = *out_prot;
1326 int ulimit = 0;
1327 struct mm_struct *mm = NULL;
1328
1329 /* Unsupported flags */
1330 if (map_flags & ~(SCIF_MAP_KERNEL | SCIF_MAP_ULIMIT))
1331 return -EINVAL;
1332 ulimit = !!(map_flags & SCIF_MAP_ULIMIT);
1333
1334 /* Unsupported protection requested */
1335 if (prot & ~(SCIF_PROT_READ | SCIF_PROT_WRITE))
1336 return -EINVAL;
1337
1338 /* addr/len must be page aligned. len should be non zero */
1339 if (!len ||
1340 (ALIGN((u64)addr, PAGE_SIZE) != (u64)addr) ||
1341 (ALIGN((u64)len, PAGE_SIZE) != (u64)len))
1342 return -EINVAL;
1343
1344 might_sleep();
1345
1346 nr_pages = len >> PAGE_SHIFT;
1347
1348 /* Allocate a set of pinned pages */
1349 pinned_pages = scif_create_pinned_pages(nr_pages, prot);
1350 if (!pinned_pages)
1351 return -ENOMEM;
1352
1353 if (map_flags & SCIF_MAP_KERNEL) {
1354 if (is_vmalloc_addr(addr))
1355 vmalloc_addr = true;
1356
1357 for (i = 0; i < nr_pages; i++) {
1358 if (vmalloc_addr)
1359 pinned_pages->pages[i] =
1360 vmalloc_to_page(addr + (i * PAGE_SIZE));
1361 else
1362 pinned_pages->pages[i] =
1363 virt_to_page(addr + (i * PAGE_SIZE));
1364 }
1365 pinned_pages->nr_pages = nr_pages;
1366 pinned_pages->map_flags = SCIF_MAP_KERNEL;
1367 } else {
1368 /*
1369 * SCIF supports registration caching. If a registration has
1370 * been requested with read only permissions, then we try
1371 * to pin the pages with RW permissions so that a subsequent
1372 * transfer with RW permission can hit the cache instead of
1373 * invalidating it. If the upgrade fails with RW then we
1374 * revert back to R permission and retry
1375 */
1376 if (prot == SCIF_PROT_READ)
1377 try_upgrade = true;
1378 prot |= SCIF_PROT_WRITE;
1379retry:
1380 mm = current->mm;
1381 if (ulimit) {
1382 err = __scif_check_inc_pinned_vm(mm, nr_pages);
1383 if (err) {
1384 pinned_pages->nr_pages = 0;
1385 goto error_unmap;
1386 }
1387 }
1388
1389 pinned_pages->nr_pages = pin_user_pages_fast(
1390 (u64)addr,
1391 nr_pages,
1392 (prot & SCIF_PROT_WRITE) ? FOLL_WRITE : 0,
1393 pinned_pages->pages);
1394 if (nr_pages != pinned_pages->nr_pages) {
1395 if (try_upgrade) {
1396 if (ulimit)
1397 __scif_dec_pinned_vm_lock(mm, nr_pages);
1398 /* Roll back any pinned pages */
1399 unpin_user_pages(pinned_pages->pages,
1400 pinned_pages->nr_pages);
1401 prot &= ~SCIF_PROT_WRITE;
1402 try_upgrade = false;
1403 goto retry;
1404 }
1405 }
1406 pinned_pages->map_flags = 0;
1407 }
1408
1409 if (pinned_pages->nr_pages < nr_pages) {
1410 err = -EFAULT;
1411 pinned_pages->nr_pages = nr_pages;
1412 goto dec_pinned;
1413 }
1414
1415 *out_prot = prot;
1416 atomic_set(&pinned_pages->ref_count, 1);
1417 *pages = pinned_pages;
1418 return err;
1419dec_pinned:
1420 if (ulimit)
1421 __scif_dec_pinned_vm_lock(mm, nr_pages);
1422 /* Something went wrong! Rollback */
1423error_unmap:
1424 pinned_pages->nr_pages = nr_pages;
1425 scif_destroy_pinned_pages(pinned_pages);
1426 *pages = NULL;
1427 dev_dbg(scif_info.mdev.this_device,
1428 "%s %d err %d len 0x%lx\n", __func__, __LINE__, err, len);
1429 return err;
1430}
1431
1432int scif_pin_pages(void *addr, size_t len, int prot,
1433 int map_flags, scif_pinned_pages_t *pages)
1434{
1435 return __scif_pin_pages(addr, len, &prot, map_flags, pages);
1436}
1437EXPORT_SYMBOL_GPL(scif_pin_pages);
1438
1439int scif_unpin_pages(scif_pinned_pages_t pinned_pages)
1440{
1441 int err = 0, ret;
1442
1443 if (!pinned_pages || SCIFEP_MAGIC != pinned_pages->magic)
1444 return -EINVAL;
1445
1446 ret = atomic_sub_return(1, &pinned_pages->ref_count);
1447 if (ret < 0) {
1448 dev_err(scif_info.mdev.this_device,
1449 "%s %d scif_unpin_pages called without pinning? rc %d\n",
1450 __func__, __LINE__, ret);
1451 return -EINVAL;
1452 }
1453 /*
1454 * Destroy the window if the ref count for this set of pinned
1455 * pages has dropped to zero. If it is positive then there is
1456 * a valid registered window which is backed by these pages and
1457 * it will be destroyed once all such windows are unregistered.
1458 */
1459 if (!ret)
1460 err = scif_destroy_pinned_pages(pinned_pages);
1461
1462 return err;
1463}
1464EXPORT_SYMBOL_GPL(scif_unpin_pages);
1465
1466static inline void
1467scif_insert_local_window(struct scif_window *window, struct scif_endpt *ep)
1468{
1469 mutex_lock(&ep->rma_info.rma_lock);
1470 scif_insert_window(window, &ep->rma_info.reg_list);
1471 mutex_unlock(&ep->rma_info.rma_lock);
1472}
1473
1474off_t scif_register_pinned_pages(scif_epd_t epd,
1475 scif_pinned_pages_t pinned_pages,
1476 off_t offset, int map_flags)
1477{
1478 struct scif_endpt *ep = (struct scif_endpt *)epd;
1479 s64 computed_offset;
1480 struct scif_window *window;
1481 int err;
1482 size_t len;
1483 struct device *spdev;
1484
1485 /* Unsupported flags */
1486 if (map_flags & ~SCIF_MAP_FIXED)
1487 return -EINVAL;
1488
1489 len = pinned_pages->nr_pages << PAGE_SHIFT;
1490
1491 /*
1492 * Offset is not page aligned/negative or offset+len
1493 * wraps around with SCIF_MAP_FIXED.
1494 */
1495 if ((map_flags & SCIF_MAP_FIXED) &&
1496 ((ALIGN(offset, PAGE_SIZE) != offset) ||
1497 (offset < 0) ||
1498 (len > LONG_MAX - offset)))
1499 return -EINVAL;
1500
1501 might_sleep();
1502
1503 err = scif_verify_epd(ep);
1504 if (err)
1505 return err;
1506 /*
1507 * It is an error to pass pinned_pages to scif_register_pinned_pages()
1508 * after calling scif_unpin_pages().
1509 */
1510 if (!atomic_add_unless(&pinned_pages->ref_count, 1, 0))
1511 return -EINVAL;
1512
1513 /* Compute the offset for this registration */
1514 err = scif_get_window_offset(ep, map_flags, offset,
1515 len, &computed_offset);
1516 if (err) {
1517 atomic_sub(1, &pinned_pages->ref_count);
1518 return err;
1519 }
1520
1521 /* Allocate and prepare self registration window */
1522 window = scif_create_window(ep, pinned_pages->nr_pages,
1523 computed_offset, false);
1524 if (!window) {
1525 atomic_sub(1, &pinned_pages->ref_count);
1526 scif_free_window_offset(ep, NULL, computed_offset);
1527 return -ENOMEM;
1528 }
1529
1530 window->pinned_pages = pinned_pages;
1531 window->nr_pages = pinned_pages->nr_pages;
1532 window->prot = pinned_pages->prot;
1533
1534 spdev = scif_get_peer_dev(ep->remote_dev);
1535 if (IS_ERR(spdev)) {
1536 err = PTR_ERR(spdev);
1537 scif_destroy_window(ep, window);
1538 return err;
1539 }
1540 err = scif_send_alloc_request(ep, window);
1541 if (err) {
1542 dev_err(&ep->remote_dev->sdev->dev,
1543 "%s %d err %d\n", __func__, __LINE__, err);
1544 goto error_unmap;
1545 }
1546
1547 /* Prepare the remote registration window */
1548 err = scif_prep_remote_window(ep, window);
1549 if (err) {
1550 dev_err(&ep->remote_dev->sdev->dev,
1551 "%s %d err %d\n", __func__, __LINE__, err);
1552 goto error_unmap;
1553 }
1554
1555 /* Tell the peer about the new window */
1556 err = scif_send_scif_register(ep, window);
1557 if (err) {
1558 dev_err(&ep->remote_dev->sdev->dev,
1559 "%s %d err %d\n", __func__, __LINE__, err);
1560 goto error_unmap;
1561 }
1562
1563 scif_put_peer_dev(spdev);
1564 /* No further failures expected. Insert new window */
1565 scif_insert_local_window(window, ep);
1566 return computed_offset;
1567error_unmap:
1568 scif_destroy_window(ep, window);
1569 scif_put_peer_dev(spdev);
1570 dev_err(&ep->remote_dev->sdev->dev,
1571 "%s %d err %d\n", __func__, __LINE__, err);
1572 return err;
1573}
1574EXPORT_SYMBOL_GPL(scif_register_pinned_pages);
1575
1576off_t scif_register(scif_epd_t epd, void *addr, size_t len, off_t offset,
1577 int prot, int map_flags)
1578{
1579 scif_pinned_pages_t pinned_pages;
1580 off_t err;
1581 struct scif_endpt *ep = (struct scif_endpt *)epd;
1582 s64 computed_offset;
1583 struct scif_window *window;
1584 struct mm_struct *mm = NULL;
1585 struct device *spdev;
1586
1587 dev_dbg(scif_info.mdev.this_device,
1588 "SCIFAPI register: ep %p addr %p len 0x%lx offset 0x%lx prot 0x%x map_flags 0x%x\n",
1589 epd, addr, len, offset, prot, map_flags);
1590 /* Unsupported flags */
1591 if (map_flags & ~(SCIF_MAP_FIXED | SCIF_MAP_KERNEL))
1592 return -EINVAL;
1593
1594 /*
1595 * Offset is not page aligned/negative or offset+len
1596 * wraps around with SCIF_MAP_FIXED.
1597 */
1598 if ((map_flags & SCIF_MAP_FIXED) &&
1599 ((ALIGN(offset, PAGE_SIZE) != offset) ||
1600 (offset < 0) ||
1601 (len > LONG_MAX - offset)))
1602 return -EINVAL;
1603
1604 /* Unsupported protection requested */
1605 if (prot & ~(SCIF_PROT_READ | SCIF_PROT_WRITE))
1606 return -EINVAL;
1607
1608 /* addr/len must be page aligned. len should be non zero */
1609 if (!len || (ALIGN((u64)addr, PAGE_SIZE) != (u64)addr) ||
1610 (ALIGN(len, PAGE_SIZE) != len))
1611 return -EINVAL;
1612
1613 might_sleep();
1614
1615 err = scif_verify_epd(ep);
1616 if (err)
1617 return err;
1618
1619 /* Compute the offset for this registration */
1620 err = scif_get_window_offset(ep, map_flags, offset,
1621 len >> PAGE_SHIFT, &computed_offset);
1622 if (err)
1623 return err;
1624
1625 spdev = scif_get_peer_dev(ep->remote_dev);
1626 if (IS_ERR(spdev)) {
1627 err = PTR_ERR(spdev);
1628 scif_free_window_offset(ep, NULL, computed_offset);
1629 return err;
1630 }
1631 /* Allocate and prepare self registration window */
1632 window = scif_create_window(ep, len >> PAGE_SHIFT,
1633 computed_offset, false);
1634 if (!window) {
1635 scif_free_window_offset(ep, NULL, computed_offset);
1636 scif_put_peer_dev(spdev);
1637 return -ENOMEM;
1638 }
1639
1640 window->nr_pages = len >> PAGE_SHIFT;
1641
1642 err = scif_send_alloc_request(ep, window);
1643 if (err) {
1644 scif_destroy_incomplete_window(ep, window);
1645 scif_put_peer_dev(spdev);
1646 return err;
1647 }
1648
1649 if (!(map_flags & SCIF_MAP_KERNEL)) {
1650 mm = __scif_acquire_mm();
1651 map_flags |= SCIF_MAP_ULIMIT;
1652 }
1653 /* Pin down the pages */
1654 err = __scif_pin_pages(addr, len, &prot,
1655 map_flags & (SCIF_MAP_KERNEL | SCIF_MAP_ULIMIT),
1656 &pinned_pages);
1657 if (err) {
1658 scif_destroy_incomplete_window(ep, window);
1659 __scif_release_mm(mm);
1660 goto error;
1661 }
1662
1663 window->pinned_pages = pinned_pages;
1664 window->prot = pinned_pages->prot;
1665 window->mm = mm;
1666
1667 /* Prepare the remote registration window */
1668 err = scif_prep_remote_window(ep, window);
1669 if (err) {
1670 dev_err(&ep->remote_dev->sdev->dev,
1671 "%s %d err %ld\n", __func__, __LINE__, err);
1672 goto error_unmap;
1673 }
1674
1675 /* Tell the peer about the new window */
1676 err = scif_send_scif_register(ep, window);
1677 if (err) {
1678 dev_err(&ep->remote_dev->sdev->dev,
1679 "%s %d err %ld\n", __func__, __LINE__, err);
1680 goto error_unmap;
1681 }
1682
1683 scif_put_peer_dev(spdev);
1684 /* No further failures expected. Insert new window */
1685 scif_insert_local_window(window, ep);
1686 dev_dbg(&ep->remote_dev->sdev->dev,
1687 "SCIFAPI register: ep %p addr %p len 0x%lx computed_offset 0x%llx\n",
1688 epd, addr, len, computed_offset);
1689 return computed_offset;
1690error_unmap:
1691 scif_destroy_window(ep, window);
1692error:
1693 scif_put_peer_dev(spdev);
1694 dev_err(&ep->remote_dev->sdev->dev,
1695 "%s %d err %ld\n", __func__, __LINE__, err);
1696 return err;
1697}
1698EXPORT_SYMBOL_GPL(scif_register);
1699
1700int
1701scif_unregister(scif_epd_t epd, off_t offset, size_t len)
1702{
1703 struct scif_endpt *ep = (struct scif_endpt *)epd;
1704 struct scif_window *window = NULL;
1705 struct scif_rma_req req;
1706 int nr_pages, err;
1707 struct device *spdev;
1708
1709 dev_dbg(scif_info.mdev.this_device,
1710 "SCIFAPI unregister: ep %p offset 0x%lx len 0x%lx\n",
1711 ep, offset, len);
1712 /* len must be page aligned. len should be non zero */
1713 if (!len ||
1714 (ALIGN((u64)len, PAGE_SIZE) != (u64)len))
1715 return -EINVAL;
1716
1717 /* Offset is not page aligned or offset+len wraps around */
1718 if ((ALIGN(offset, PAGE_SIZE) != offset) ||
1719 (offset < 0) ||
1720 (len > LONG_MAX - offset))
1721 return -EINVAL;
1722
1723 err = scif_verify_epd(ep);
1724 if (err)
1725 return err;
1726
1727 might_sleep();
1728 nr_pages = len >> PAGE_SHIFT;
1729
1730 req.out_window = &window;
1731 req.offset = offset;
1732 req.prot = 0;
1733 req.nr_bytes = len;
1734 req.type = SCIF_WINDOW_FULL;
1735 req.head = &ep->rma_info.reg_list;
1736
1737 spdev = scif_get_peer_dev(ep->remote_dev);
1738 if (IS_ERR(spdev)) {
1739 err = PTR_ERR(spdev);
1740 return err;
1741 }
1742 mutex_lock(&ep->rma_info.rma_lock);
1743 /* Does a valid window exist? */
1744 err = scif_query_window(&req);
1745 if (err) {
1746 dev_err(&ep->remote_dev->sdev->dev,
1747 "%s %d err %d\n", __func__, __LINE__, err);
1748 goto error;
1749 }
1750 /* Unregister all the windows in this range */
1751 err = scif_rma_list_unregister(window, offset, nr_pages);
1752 if (err)
1753 dev_err(&ep->remote_dev->sdev->dev,
1754 "%s %d err %d\n", __func__, __LINE__, err);
1755error:
1756 mutex_unlock(&ep->rma_info.rma_lock);
1757 scif_put_peer_dev(spdev);
1758 return err;
1759}
1760EXPORT_SYMBOL_GPL(scif_unregister);