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 "scif_main.h"
21 #include "scif_map.h"
22
23 /* Used to skip ulimit checks for registrations with SCIF_MAP_KERNEL flag */
24 #define SCIF_MAP_ULIMIT 0x40
25
26 bool scif_ulimit_check = 1;
27
28 /**
29 * scif_rma_ep_init:
30 * @ep: end point
31 *
32 * Initialize RMA per EP data structures.
33 */
scif_rma_ep_init(struct scif_endpt * ep)34 void scif_rma_ep_init(struct scif_endpt *ep)
35 {
36 struct scif_endpt_rma_info *rma = &ep->rma_info;
37
38 mutex_init(&rma->rma_lock);
39 init_iova_domain(&rma->iovad, PAGE_SIZE, SCIF_IOVA_START_PFN,
40 SCIF_DMA_64BIT_PFN);
41 spin_lock_init(&rma->tc_lock);
42 mutex_init(&rma->mmn_lock);
43 INIT_LIST_HEAD(&rma->reg_list);
44 INIT_LIST_HEAD(&rma->remote_reg_list);
45 atomic_set(&rma->tw_refcount, 0);
46 atomic_set(&rma->tcw_refcount, 0);
47 atomic_set(&rma->tcw_total_pages, 0);
48 atomic_set(&rma->fence_refcount, 0);
49
50 rma->async_list_del = 0;
51 rma->dma_chan = NULL;
52 INIT_LIST_HEAD(&rma->mmn_list);
53 INIT_LIST_HEAD(&rma->vma_list);
54 init_waitqueue_head(&rma->markwq);
55 }
56
57 /**
58 * scif_rma_ep_can_uninit:
59 * @ep: end point
60 *
61 * Returns 1 if an endpoint can be uninitialized and 0 otherwise.
62 */
scif_rma_ep_can_uninit(struct scif_endpt * ep)63 int scif_rma_ep_can_uninit(struct scif_endpt *ep)
64 {
65 int ret = 0;
66
67 mutex_lock(&ep->rma_info.rma_lock);
68 /* Destroy RMA Info only if both lists are empty */
69 if (list_empty(&ep->rma_info.reg_list) &&
70 list_empty(&ep->rma_info.remote_reg_list) &&
71 list_empty(&ep->rma_info.mmn_list) &&
72 !atomic_read(&ep->rma_info.tw_refcount) &&
73 !atomic_read(&ep->rma_info.tcw_refcount) &&
74 !atomic_read(&ep->rma_info.fence_refcount))
75 ret = 1;
76 mutex_unlock(&ep->rma_info.rma_lock);
77 return ret;
78 }
79
80 /**
81 * scif_create_pinned_pages:
82 * @nr_pages: number of pages in window
83 * @prot: read/write protection
84 *
85 * Allocate and prepare a set of pinned pages.
86 */
87 static struct scif_pinned_pages *
scif_create_pinned_pages(int nr_pages,int prot)88 scif_create_pinned_pages(int nr_pages, int prot)
89 {
90 struct scif_pinned_pages *pin;
91
92 might_sleep();
93 pin = scif_zalloc(sizeof(*pin));
94 if (!pin)
95 goto error;
96
97 pin->pages = scif_zalloc(nr_pages * sizeof(*pin->pages));
98 if (!pin->pages)
99 goto error_free_pinned_pages;
100
101 pin->prot = prot;
102 pin->magic = SCIFEP_MAGIC;
103 return pin;
104
105 error_free_pinned_pages:
106 scif_free(pin, sizeof(*pin));
107 error:
108 return NULL;
109 }
110
111 /**
112 * scif_destroy_pinned_pages:
113 * @pin: A set of pinned pages.
114 *
115 * Deallocate resources for pinned pages.
116 */
scif_destroy_pinned_pages(struct scif_pinned_pages * pin)117 static int scif_destroy_pinned_pages(struct scif_pinned_pages *pin)
118 {
119 int j;
120 int writeable = pin->prot & SCIF_PROT_WRITE;
121 int kernel = SCIF_MAP_KERNEL & pin->map_flags;
122
123 for (j = 0; j < pin->nr_pages; j++) {
124 if (pin->pages[j] && !kernel) {
125 if (writeable)
126 SetPageDirty(pin->pages[j]);
127 put_page(pin->pages[j]);
128 }
129 }
130
131 scif_free(pin->pages,
132 pin->nr_pages * sizeof(*pin->pages));
133 scif_free(pin, sizeof(*pin));
134 return 0;
135 }
136
137 /*
138 * scif_create_window:
139 * @ep: end point
140 * @nr_pages: number of pages
141 * @offset: registration offset
142 * @temp: true if a temporary window is being created
143 *
144 * Allocate and prepare a self registration window.
145 */
scif_create_window(struct scif_endpt * ep,int nr_pages,s64 offset,bool temp)146 struct scif_window *scif_create_window(struct scif_endpt *ep, int nr_pages,
147 s64 offset, bool temp)
148 {
149 struct scif_window *window;
150
151 might_sleep();
152 window = scif_zalloc(sizeof(*window));
153 if (!window)
154 goto error;
155
156 window->dma_addr = scif_zalloc(nr_pages * sizeof(*window->dma_addr));
157 if (!window->dma_addr)
158 goto error_free_window;
159
160 window->num_pages = scif_zalloc(nr_pages * sizeof(*window->num_pages));
161 if (!window->num_pages)
162 goto error_free_window;
163
164 window->offset = offset;
165 window->ep = (u64)ep;
166 window->magic = SCIFEP_MAGIC;
167 window->reg_state = OP_IDLE;
168 init_waitqueue_head(&window->regwq);
169 window->unreg_state = OP_IDLE;
170 init_waitqueue_head(&window->unregwq);
171 INIT_LIST_HEAD(&window->list);
172 window->type = SCIF_WINDOW_SELF;
173 window->temp = temp;
174 return window;
175
176 error_free_window:
177 scif_free(window->dma_addr,
178 nr_pages * sizeof(*window->dma_addr));
179 scif_free(window, sizeof(*window));
180 error:
181 return NULL;
182 }
183
184 /**
185 * scif_destroy_incomplete_window:
186 * @ep: end point
187 * @window: registration window
188 *
189 * Deallocate resources for self window.
190 */
scif_destroy_incomplete_window(struct scif_endpt * ep,struct scif_window * window)191 static void scif_destroy_incomplete_window(struct scif_endpt *ep,
192 struct scif_window *window)
193 {
194 int err;
195 int nr_pages = window->nr_pages;
196 struct scif_allocmsg *alloc = &window->alloc_handle;
197 struct scifmsg msg;
198
199 retry:
200 /* Wait for a SCIF_ALLOC_GNT/REJ message */
201 err = wait_event_timeout(alloc->allocwq,
202 alloc->state != OP_IN_PROGRESS,
203 SCIF_NODE_ALIVE_TIMEOUT);
204 if (!err && scifdev_alive(ep))
205 goto retry;
206
207 mutex_lock(&ep->rma_info.rma_lock);
208 if (alloc->state == OP_COMPLETED) {
209 msg.uop = SCIF_FREE_VIRT;
210 msg.src = ep->port;
211 msg.payload[0] = ep->remote_ep;
212 msg.payload[1] = window->alloc_handle.vaddr;
213 msg.payload[2] = (u64)window;
214 msg.payload[3] = SCIF_REGISTER;
215 _scif_nodeqp_send(ep->remote_dev, &msg);
216 }
217 mutex_unlock(&ep->rma_info.rma_lock);
218
219 scif_free_window_offset(ep, window, window->offset);
220 scif_free(window->dma_addr, nr_pages * sizeof(*window->dma_addr));
221 scif_free(window->num_pages, nr_pages * sizeof(*window->num_pages));
222 scif_free(window, sizeof(*window));
223 }
224
225 /**
226 * scif_unmap_window:
227 * @remote_dev: SCIF remote device
228 * @window: registration window
229 *
230 * Delete any DMA mappings created for a registered self window
231 */
scif_unmap_window(struct scif_dev * remote_dev,struct scif_window * window)232 void scif_unmap_window(struct scif_dev *remote_dev, struct scif_window *window)
233 {
234 int j;
235
236 if (scif_is_iommu_enabled() && !scifdev_self(remote_dev)) {
237 if (window->st) {
238 dma_unmap_sg(&remote_dev->sdev->dev,
239 window->st->sgl, window->st->nents,
240 DMA_BIDIRECTIONAL);
241 sg_free_table(window->st);
242 kfree(window->st);
243 window->st = NULL;
244 }
245 } else {
246 for (j = 0; j < window->nr_contig_chunks; j++) {
247 if (window->dma_addr[j]) {
248 scif_unmap_single(window->dma_addr[j],
249 remote_dev,
250 window->num_pages[j] <<
251 PAGE_SHIFT);
252 window->dma_addr[j] = 0x0;
253 }
254 }
255 }
256 }
257
__scif_acquire_mm(void)258 static inline struct mm_struct *__scif_acquire_mm(void)
259 {
260 if (scif_ulimit_check)
261 return get_task_mm(current);
262 return NULL;
263 }
264
__scif_release_mm(struct mm_struct * mm)265 static inline void __scif_release_mm(struct mm_struct *mm)
266 {
267 if (mm)
268 mmput(mm);
269 }
270
271 static inline int
__scif_dec_pinned_vm_lock(struct mm_struct * mm,int nr_pages,bool try_lock)272 __scif_dec_pinned_vm_lock(struct mm_struct *mm,
273 int nr_pages, bool try_lock)
274 {
275 if (!mm || !nr_pages || !scif_ulimit_check)
276 return 0;
277 if (try_lock) {
278 if (!down_write_trylock(&mm->mmap_sem)) {
279 dev_err(scif_info.mdev.this_device,
280 "%s %d err\n", __func__, __LINE__);
281 return -1;
282 }
283 } else {
284 down_write(&mm->mmap_sem);
285 }
286 mm->pinned_vm -= nr_pages;
287 up_write(&mm->mmap_sem);
288 return 0;
289 }
290
__scif_check_inc_pinned_vm(struct mm_struct * mm,int nr_pages)291 static inline int __scif_check_inc_pinned_vm(struct mm_struct *mm,
292 int nr_pages)
293 {
294 unsigned long locked, lock_limit;
295
296 if (!mm || !nr_pages || !scif_ulimit_check)
297 return 0;
298
299 locked = nr_pages;
300 locked += mm->pinned_vm;
301 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
302 if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
303 dev_err(scif_info.mdev.this_device,
304 "locked(%lu) > lock_limit(%lu)\n",
305 locked, lock_limit);
306 return -ENOMEM;
307 }
308 mm->pinned_vm = locked;
309 return 0;
310 }
311
312 /**
313 * scif_destroy_window:
314 * @ep: end point
315 * @window: registration window
316 *
317 * Deallocate resources for self window.
318 */
scif_destroy_window(struct scif_endpt * ep,struct scif_window * window)319 int scif_destroy_window(struct scif_endpt *ep, struct scif_window *window)
320 {
321 int j;
322 struct scif_pinned_pages *pinned_pages = window->pinned_pages;
323 int nr_pages = window->nr_pages;
324
325 might_sleep();
326 if (!window->temp && window->mm) {
327 __scif_dec_pinned_vm_lock(window->mm, window->nr_pages, 0);
328 __scif_release_mm(window->mm);
329 window->mm = NULL;
330 }
331
332 scif_free_window_offset(ep, window, window->offset);
333 scif_unmap_window(ep->remote_dev, window);
334 /*
335 * Decrement references for this set of pinned pages from
336 * this window.
337 */
338 j = atomic_sub_return(1, &pinned_pages->ref_count);
339 if (j < 0)
340 dev_err(scif_info.mdev.this_device,
341 "%s %d incorrect ref count %d\n",
342 __func__, __LINE__, j);
343 /*
344 * If the ref count for pinned_pages is zero then someone
345 * has already called scif_unpin_pages() for it and we should
346 * destroy the page cache.
347 */
348 if (!j)
349 scif_destroy_pinned_pages(window->pinned_pages);
350 scif_free(window->dma_addr, nr_pages * sizeof(*window->dma_addr));
351 scif_free(window->num_pages, nr_pages * sizeof(*window->num_pages));
352 window->magic = 0;
353 scif_free(window, sizeof(*window));
354 return 0;
355 }
356
357 /**
358 * scif_create_remote_lookup:
359 * @remote_dev: SCIF remote device
360 * @window: remote window
361 *
362 * Allocate and prepare lookup entries for the remote
363 * end to copy over the physical addresses.
364 * Returns 0 on success and appropriate errno on failure.
365 */
scif_create_remote_lookup(struct scif_dev * remote_dev,struct scif_window * window)366 static int scif_create_remote_lookup(struct scif_dev *remote_dev,
367 struct scif_window *window)
368 {
369 int i, j, err = 0;
370 int nr_pages = window->nr_pages;
371 bool vmalloc_dma_phys, vmalloc_num_pages;
372
373 might_sleep();
374 /* Map window */
375 err = scif_map_single(&window->mapped_offset,
376 window, remote_dev, sizeof(*window));
377 if (err)
378 goto error_window;
379
380 /* Compute the number of lookup entries. 21 == 2MB Shift */
381 window->nr_lookup = ALIGN(nr_pages * PAGE_SIZE,
382 ((2) * 1024 * 1024)) >> 21;
383
384 window->dma_addr_lookup.lookup =
385 scif_alloc_coherent(&window->dma_addr_lookup.offset,
386 remote_dev, window->nr_lookup *
387 sizeof(*window->dma_addr_lookup.lookup),
388 GFP_KERNEL | __GFP_ZERO);
389 if (!window->dma_addr_lookup.lookup) {
390 err = -ENOMEM;
391 goto error_window;
392 }
393
394 window->num_pages_lookup.lookup =
395 scif_alloc_coherent(&window->num_pages_lookup.offset,
396 remote_dev, window->nr_lookup *
397 sizeof(*window->num_pages_lookup.lookup),
398 GFP_KERNEL | __GFP_ZERO);
399 if (!window->num_pages_lookup.lookup) {
400 err = -ENOMEM;
401 goto error_window;
402 }
403
404 vmalloc_dma_phys = is_vmalloc_addr(&window->dma_addr[0]);
405 vmalloc_num_pages = is_vmalloc_addr(&window->num_pages[0]);
406
407 /* Now map each of the pages containing physical addresses */
408 for (i = 0, j = 0; i < nr_pages; i += SCIF_NR_ADDR_IN_PAGE, j++) {
409 err = scif_map_page(&window->dma_addr_lookup.lookup[j],
410 vmalloc_dma_phys ?
411 vmalloc_to_page(&window->dma_addr[i]) :
412 virt_to_page(&window->dma_addr[i]),
413 remote_dev);
414 if (err)
415 goto error_window;
416 err = scif_map_page(&window->num_pages_lookup.lookup[j],
417 vmalloc_dma_phys ?
418 vmalloc_to_page(&window->num_pages[i]) :
419 virt_to_page(&window->num_pages[i]),
420 remote_dev);
421 if (err)
422 goto error_window;
423 }
424 return 0;
425 error_window:
426 return err;
427 }
428
429 /**
430 * scif_destroy_remote_lookup:
431 * @remote_dev: SCIF remote device
432 * @window: remote window
433 *
434 * Destroy lookup entries used for the remote
435 * end to copy over the physical addresses.
436 */
scif_destroy_remote_lookup(struct scif_dev * remote_dev,struct scif_window * window)437 static void scif_destroy_remote_lookup(struct scif_dev *remote_dev,
438 struct scif_window *window)
439 {
440 int i, j;
441
442 if (window->nr_lookup) {
443 struct scif_rma_lookup *lup = &window->dma_addr_lookup;
444 struct scif_rma_lookup *npup = &window->num_pages_lookup;
445
446 for (i = 0, j = 0; i < window->nr_pages;
447 i += SCIF_NR_ADDR_IN_PAGE, j++) {
448 if (lup->lookup && lup->lookup[j])
449 scif_unmap_single(lup->lookup[j],
450 remote_dev,
451 PAGE_SIZE);
452 if (npup->lookup && npup->lookup[j])
453 scif_unmap_single(npup->lookup[j],
454 remote_dev,
455 PAGE_SIZE);
456 }
457 if (lup->lookup)
458 scif_free_coherent(lup->lookup, lup->offset,
459 remote_dev, window->nr_lookup *
460 sizeof(*lup->lookup));
461 if (npup->lookup)
462 scif_free_coherent(npup->lookup, npup->offset,
463 remote_dev, window->nr_lookup *
464 sizeof(*npup->lookup));
465 if (window->mapped_offset)
466 scif_unmap_single(window->mapped_offset,
467 remote_dev, sizeof(*window));
468 window->nr_lookup = 0;
469 }
470 }
471
472 /**
473 * scif_create_remote_window:
474 * @ep: end point
475 * @nr_pages: number of pages in window
476 *
477 * Allocate and prepare a remote registration window.
478 */
479 static struct scif_window *
scif_create_remote_window(struct scif_dev * scifdev,int nr_pages)480 scif_create_remote_window(struct scif_dev *scifdev, int nr_pages)
481 {
482 struct scif_window *window;
483
484 might_sleep();
485 window = scif_zalloc(sizeof(*window));
486 if (!window)
487 goto error_ret;
488
489 window->magic = SCIFEP_MAGIC;
490 window->nr_pages = nr_pages;
491
492 window->dma_addr = scif_zalloc(nr_pages * sizeof(*window->dma_addr));
493 if (!window->dma_addr)
494 goto error_window;
495
496 window->num_pages = scif_zalloc(nr_pages *
497 sizeof(*window->num_pages));
498 if (!window->num_pages)
499 goto error_window;
500
501 if (scif_create_remote_lookup(scifdev, window))
502 goto error_window;
503
504 window->type = SCIF_WINDOW_PEER;
505 window->unreg_state = OP_IDLE;
506 INIT_LIST_HEAD(&window->list);
507 return window;
508 error_window:
509 scif_destroy_remote_window(window);
510 error_ret:
511 return NULL;
512 }
513
514 /**
515 * scif_destroy_remote_window:
516 * @ep: end point
517 * @window: remote registration window
518 *
519 * Deallocate resources for remote window.
520 */
521 void
scif_destroy_remote_window(struct scif_window * window)522 scif_destroy_remote_window(struct scif_window *window)
523 {
524 scif_free(window->dma_addr, window->nr_pages *
525 sizeof(*window->dma_addr));
526 scif_free(window->num_pages, window->nr_pages *
527 sizeof(*window->num_pages));
528 window->magic = 0;
529 scif_free(window, sizeof(*window));
530 }
531
532 /**
533 * scif_iommu_map: create DMA mappings if the IOMMU is enabled
534 * @remote_dev: SCIF remote device
535 * @window: remote registration window
536 *
537 * Map the physical pages using dma_map_sg(..) and then detect the number
538 * of contiguous DMA mappings allocated
539 */
scif_iommu_map(struct scif_dev * remote_dev,struct scif_window * window)540 static int scif_iommu_map(struct scif_dev *remote_dev,
541 struct scif_window *window)
542 {
543 struct scatterlist *sg;
544 int i, err;
545 scif_pinned_pages_t pin = window->pinned_pages;
546
547 window->st = kzalloc(sizeof(*window->st), GFP_KERNEL);
548 if (!window->st)
549 return -ENOMEM;
550
551 err = sg_alloc_table(window->st, window->nr_pages, GFP_KERNEL);
552 if (err)
553 return err;
554
555 for_each_sg(window->st->sgl, sg, window->st->nents, i)
556 sg_set_page(sg, pin->pages[i], PAGE_SIZE, 0x0);
557
558 err = dma_map_sg(&remote_dev->sdev->dev, window->st->sgl,
559 window->st->nents, DMA_BIDIRECTIONAL);
560 if (!err)
561 return -ENOMEM;
562 /* Detect contiguous ranges of DMA mappings */
563 sg = window->st->sgl;
564 for (i = 0; sg; i++) {
565 dma_addr_t last_da;
566
567 window->dma_addr[i] = sg_dma_address(sg);
568 window->num_pages[i] = sg_dma_len(sg) >> PAGE_SHIFT;
569 last_da = sg_dma_address(sg) + sg_dma_len(sg);
570 while ((sg = sg_next(sg)) && sg_dma_address(sg) == last_da) {
571 window->num_pages[i] +=
572 (sg_dma_len(sg) >> PAGE_SHIFT);
573 last_da = window->dma_addr[i] +
574 sg_dma_len(sg);
575 }
576 window->nr_contig_chunks++;
577 }
578 return 0;
579 }
580
581 /**
582 * scif_map_window:
583 * @remote_dev: SCIF remote device
584 * @window: self registration window
585 *
586 * Map pages of a window into the aperture/PCI.
587 * Also determine addresses required for DMA.
588 */
589 int
scif_map_window(struct scif_dev * remote_dev,struct scif_window * window)590 scif_map_window(struct scif_dev *remote_dev, struct scif_window *window)
591 {
592 int i, j, k, err = 0, nr_contig_pages;
593 scif_pinned_pages_t pin;
594 phys_addr_t phys_prev, phys_curr;
595
596 might_sleep();
597
598 pin = window->pinned_pages;
599
600 if (intel_iommu_enabled && !scifdev_self(remote_dev))
601 return scif_iommu_map(remote_dev, window);
602
603 for (i = 0, j = 0; i < window->nr_pages; i += nr_contig_pages, j++) {
604 phys_prev = page_to_phys(pin->pages[i]);
605 nr_contig_pages = 1;
606
607 /* Detect physically contiguous chunks */
608 for (k = i + 1; k < window->nr_pages; k++) {
609 phys_curr = page_to_phys(pin->pages[k]);
610 if (phys_curr != (phys_prev + PAGE_SIZE))
611 break;
612 phys_prev = phys_curr;
613 nr_contig_pages++;
614 }
615 window->num_pages[j] = nr_contig_pages;
616 window->nr_contig_chunks++;
617 if (scif_is_mgmt_node()) {
618 /*
619 * Management node has to deal with SMPT on X100 and
620 * hence the DMA mapping is required
621 */
622 err = scif_map_single(&window->dma_addr[j],
623 phys_to_virt(page_to_phys(
624 pin->pages[i])),
625 remote_dev,
626 nr_contig_pages << PAGE_SHIFT);
627 if (err)
628 return err;
629 } else {
630 window->dma_addr[j] = page_to_phys(pin->pages[i]);
631 }
632 }
633 return err;
634 }
635
636 /**
637 * scif_send_scif_unregister:
638 * @ep: end point
639 * @window: self registration window
640 *
641 * Send a SCIF_UNREGISTER message.
642 */
scif_send_scif_unregister(struct scif_endpt * ep,struct scif_window * window)643 static int scif_send_scif_unregister(struct scif_endpt *ep,
644 struct scif_window *window)
645 {
646 struct scifmsg msg;
647
648 msg.uop = SCIF_UNREGISTER;
649 msg.src = ep->port;
650 msg.payload[0] = window->alloc_handle.vaddr;
651 msg.payload[1] = (u64)window;
652 return scif_nodeqp_send(ep->remote_dev, &msg);
653 }
654
655 /**
656 * scif_unregister_window:
657 * @window: self registration window
658 *
659 * Send an unregistration request and wait for a response.
660 */
scif_unregister_window(struct scif_window * window)661 int scif_unregister_window(struct scif_window *window)
662 {
663 int err = 0;
664 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
665 bool send_msg = false;
666
667 might_sleep();
668 switch (window->unreg_state) {
669 case OP_IDLE:
670 {
671 window->unreg_state = OP_IN_PROGRESS;
672 send_msg = true;
673 /* fall through */
674 }
675 case OP_IN_PROGRESS:
676 {
677 scif_get_window(window, 1);
678 mutex_unlock(&ep->rma_info.rma_lock);
679 if (send_msg) {
680 err = scif_send_scif_unregister(ep, window);
681 if (err) {
682 window->unreg_state = OP_COMPLETED;
683 goto done;
684 }
685 } else {
686 /* Return ENXIO since unregistration is in progress */
687 mutex_lock(&ep->rma_info.rma_lock);
688 return -ENXIO;
689 }
690 retry:
691 /* Wait for a SCIF_UNREGISTER_(N)ACK message */
692 err = wait_event_timeout(window->unregwq,
693 window->unreg_state != OP_IN_PROGRESS,
694 SCIF_NODE_ALIVE_TIMEOUT);
695 if (!err && scifdev_alive(ep))
696 goto retry;
697 if (!err) {
698 err = -ENODEV;
699 window->unreg_state = OP_COMPLETED;
700 dev_err(scif_info.mdev.this_device,
701 "%s %d err %d\n", __func__, __LINE__, err);
702 }
703 if (err > 0)
704 err = 0;
705 done:
706 mutex_lock(&ep->rma_info.rma_lock);
707 scif_put_window(window, 1);
708 break;
709 }
710 case OP_FAILED:
711 {
712 if (!scifdev_alive(ep)) {
713 err = -ENODEV;
714 window->unreg_state = OP_COMPLETED;
715 }
716 break;
717 }
718 case OP_COMPLETED:
719 break;
720 default:
721 err = -ENODEV;
722 }
723
724 if (window->unreg_state == OP_COMPLETED && window->ref_count)
725 scif_put_window(window, window->nr_pages);
726
727 if (!window->ref_count) {
728 atomic_inc(&ep->rma_info.tw_refcount);
729 list_del_init(&window->list);
730 scif_free_window_offset(ep, window, window->offset);
731 mutex_unlock(&ep->rma_info.rma_lock);
732 if ((!!(window->pinned_pages->map_flags & SCIF_MAP_KERNEL)) &&
733 scifdev_alive(ep)) {
734 scif_drain_dma_intr(ep->remote_dev->sdev,
735 ep->rma_info.dma_chan);
736 } else {
737 if (!__scif_dec_pinned_vm_lock(window->mm,
738 window->nr_pages, 1)) {
739 __scif_release_mm(window->mm);
740 window->mm = NULL;
741 }
742 }
743 scif_queue_for_cleanup(window, &scif_info.rma);
744 mutex_lock(&ep->rma_info.rma_lock);
745 }
746 return err;
747 }
748
749 /**
750 * scif_send_alloc_request:
751 * @ep: end point
752 * @window: self registration window
753 *
754 * Send a remote window allocation request
755 */
scif_send_alloc_request(struct scif_endpt * ep,struct scif_window * window)756 static int scif_send_alloc_request(struct scif_endpt *ep,
757 struct scif_window *window)
758 {
759 struct scifmsg msg;
760 struct scif_allocmsg *alloc = &window->alloc_handle;
761
762 /* Set up the Alloc Handle */
763 alloc->state = OP_IN_PROGRESS;
764 init_waitqueue_head(&alloc->allocwq);
765
766 /* Send out an allocation request */
767 msg.uop = SCIF_ALLOC_REQ;
768 msg.payload[1] = window->nr_pages;
769 msg.payload[2] = (u64)&window->alloc_handle;
770 return _scif_nodeqp_send(ep->remote_dev, &msg);
771 }
772
773 /**
774 * scif_prep_remote_window:
775 * @ep: end point
776 * @window: self registration window
777 *
778 * Send a remote window allocation request, wait for an allocation response,
779 * and prepares the remote window by copying over the page lists
780 */
scif_prep_remote_window(struct scif_endpt * ep,struct scif_window * window)781 static int scif_prep_remote_window(struct scif_endpt *ep,
782 struct scif_window *window)
783 {
784 struct scifmsg msg;
785 struct scif_window *remote_window;
786 struct scif_allocmsg *alloc = &window->alloc_handle;
787 dma_addr_t *dma_phys_lookup, *tmp, *num_pages_lookup, *tmp1;
788 int i = 0, j = 0;
789 int nr_contig_chunks, loop_nr_contig_chunks;
790 int remaining_nr_contig_chunks, nr_lookup;
791 int err, map_err;
792
793 map_err = scif_map_window(ep->remote_dev, window);
794 if (map_err)
795 dev_err(&ep->remote_dev->sdev->dev,
796 "%s %d map_err %d\n", __func__, __LINE__, map_err);
797 remaining_nr_contig_chunks = window->nr_contig_chunks;
798 nr_contig_chunks = window->nr_contig_chunks;
799 retry:
800 /* Wait for a SCIF_ALLOC_GNT/REJ message */
801 err = wait_event_timeout(alloc->allocwq,
802 alloc->state != OP_IN_PROGRESS,
803 SCIF_NODE_ALIVE_TIMEOUT);
804 mutex_lock(&ep->rma_info.rma_lock);
805 /* Synchronize with the thread waking up allocwq */
806 mutex_unlock(&ep->rma_info.rma_lock);
807 if (!err && scifdev_alive(ep))
808 goto retry;
809
810 if (!err)
811 err = -ENODEV;
812
813 if (err > 0)
814 err = 0;
815 else
816 return err;
817
818 /* Bail out. The remote end rejected this request */
819 if (alloc->state == OP_FAILED)
820 return -ENOMEM;
821
822 if (map_err) {
823 dev_err(&ep->remote_dev->sdev->dev,
824 "%s %d err %d\n", __func__, __LINE__, map_err);
825 msg.uop = SCIF_FREE_VIRT;
826 msg.src = ep->port;
827 msg.payload[0] = ep->remote_ep;
828 msg.payload[1] = window->alloc_handle.vaddr;
829 msg.payload[2] = (u64)window;
830 msg.payload[3] = SCIF_REGISTER;
831 spin_lock(&ep->lock);
832 if (ep->state == SCIFEP_CONNECTED)
833 err = _scif_nodeqp_send(ep->remote_dev, &msg);
834 else
835 err = -ENOTCONN;
836 spin_unlock(&ep->lock);
837 return err;
838 }
839
840 remote_window = scif_ioremap(alloc->phys_addr, sizeof(*window),
841 ep->remote_dev);
842
843 /* Compute the number of lookup entries. 21 == 2MB Shift */
844 nr_lookup = ALIGN(nr_contig_chunks, SCIF_NR_ADDR_IN_PAGE)
845 >> ilog2(SCIF_NR_ADDR_IN_PAGE);
846
847 dma_phys_lookup =
848 scif_ioremap(remote_window->dma_addr_lookup.offset,
849 nr_lookup *
850 sizeof(*remote_window->dma_addr_lookup.lookup),
851 ep->remote_dev);
852 num_pages_lookup =
853 scif_ioremap(remote_window->num_pages_lookup.offset,
854 nr_lookup *
855 sizeof(*remote_window->num_pages_lookup.lookup),
856 ep->remote_dev);
857
858 while (remaining_nr_contig_chunks) {
859 loop_nr_contig_chunks = min_t(int, remaining_nr_contig_chunks,
860 (int)SCIF_NR_ADDR_IN_PAGE);
861 /* #1/2 - Copy physical addresses over to the remote side */
862
863 /* #2/2 - Copy DMA addresses (addresses that are fed into the
864 * DMA engine) We transfer bus addresses which are then
865 * converted into a MIC physical address on the remote
866 * side if it is a MIC, if the remote node is a mgmt node we
867 * transfer the MIC physical address
868 */
869 tmp = scif_ioremap(dma_phys_lookup[j],
870 loop_nr_contig_chunks *
871 sizeof(*window->dma_addr),
872 ep->remote_dev);
873 tmp1 = scif_ioremap(num_pages_lookup[j],
874 loop_nr_contig_chunks *
875 sizeof(*window->num_pages),
876 ep->remote_dev);
877 if (scif_is_mgmt_node()) {
878 memcpy_toio((void __force __iomem *)tmp,
879 &window->dma_addr[i], loop_nr_contig_chunks
880 * sizeof(*window->dma_addr));
881 memcpy_toio((void __force __iomem *)tmp1,
882 &window->num_pages[i], loop_nr_contig_chunks
883 * sizeof(*window->num_pages));
884 } else {
885 if (scifdev_is_p2p(ep->remote_dev)) {
886 /*
887 * add remote node's base address for this node
888 * to convert it into a MIC address
889 */
890 int m;
891 dma_addr_t dma_addr;
892
893 for (m = 0; m < loop_nr_contig_chunks; m++) {
894 dma_addr = window->dma_addr[i + m] +
895 ep->remote_dev->base_addr;
896 writeq(dma_addr,
897 (void __force __iomem *)&tmp[m]);
898 }
899 memcpy_toio((void __force __iomem *)tmp1,
900 &window->num_pages[i],
901 loop_nr_contig_chunks
902 * sizeof(*window->num_pages));
903 } else {
904 /* Mgmt node or loopback - transfer DMA
905 * addresses as is, this is the same as a
906 * MIC physical address (we use the dma_addr
907 * and not the phys_addr array since the
908 * phys_addr is only setup if there is a mmap()
909 * request from the mgmt node)
910 */
911 memcpy_toio((void __force __iomem *)tmp,
912 &window->dma_addr[i],
913 loop_nr_contig_chunks *
914 sizeof(*window->dma_addr));
915 memcpy_toio((void __force __iomem *)tmp1,
916 &window->num_pages[i],
917 loop_nr_contig_chunks *
918 sizeof(*window->num_pages));
919 }
920 }
921 remaining_nr_contig_chunks -= loop_nr_contig_chunks;
922 i += loop_nr_contig_chunks;
923 j++;
924 scif_iounmap(tmp, loop_nr_contig_chunks *
925 sizeof(*window->dma_addr), ep->remote_dev);
926 scif_iounmap(tmp1, loop_nr_contig_chunks *
927 sizeof(*window->num_pages), ep->remote_dev);
928 }
929
930 /* Prepare the remote window for the peer */
931 remote_window->peer_window = (u64)window;
932 remote_window->offset = window->offset;
933 remote_window->prot = window->prot;
934 remote_window->nr_contig_chunks = nr_contig_chunks;
935 remote_window->ep = ep->remote_ep;
936 scif_iounmap(num_pages_lookup,
937 nr_lookup *
938 sizeof(*remote_window->num_pages_lookup.lookup),
939 ep->remote_dev);
940 scif_iounmap(dma_phys_lookup,
941 nr_lookup *
942 sizeof(*remote_window->dma_addr_lookup.lookup),
943 ep->remote_dev);
944 scif_iounmap(remote_window, sizeof(*remote_window), ep->remote_dev);
945 window->peer_window = alloc->vaddr;
946 return err;
947 }
948
949 /**
950 * scif_send_scif_register:
951 * @ep: end point
952 * @window: self registration window
953 *
954 * Send a SCIF_REGISTER message if EP is connected and wait for a
955 * SCIF_REGISTER_(N)ACK message else send a SCIF_FREE_VIRT
956 * message so that the peer can free its remote window allocated earlier.
957 */
scif_send_scif_register(struct scif_endpt * ep,struct scif_window * window)958 static int scif_send_scif_register(struct scif_endpt *ep,
959 struct scif_window *window)
960 {
961 int err = 0;
962 struct scifmsg msg;
963
964 msg.src = ep->port;
965 msg.payload[0] = ep->remote_ep;
966 msg.payload[1] = window->alloc_handle.vaddr;
967 msg.payload[2] = (u64)window;
968 spin_lock(&ep->lock);
969 if (ep->state == SCIFEP_CONNECTED) {
970 msg.uop = SCIF_REGISTER;
971 window->reg_state = OP_IN_PROGRESS;
972 err = _scif_nodeqp_send(ep->remote_dev, &msg);
973 spin_unlock(&ep->lock);
974 if (!err) {
975 retry:
976 /* Wait for a SCIF_REGISTER_(N)ACK message */
977 err = wait_event_timeout(window->regwq,
978 window->reg_state !=
979 OP_IN_PROGRESS,
980 SCIF_NODE_ALIVE_TIMEOUT);
981 if (!err && scifdev_alive(ep))
982 goto retry;
983 err = !err ? -ENODEV : 0;
984 if (window->reg_state == OP_FAILED)
985 err = -ENOTCONN;
986 }
987 } else {
988 msg.uop = SCIF_FREE_VIRT;
989 msg.payload[3] = SCIF_REGISTER;
990 err = _scif_nodeqp_send(ep->remote_dev, &msg);
991 spin_unlock(&ep->lock);
992 if (!err)
993 err = -ENOTCONN;
994 }
995 return err;
996 }
997
998 /**
999 * scif_get_window_offset:
1000 * @ep: end point descriptor
1001 * @flags: flags
1002 * @offset: offset hint
1003 * @num_pages: number of pages
1004 * @out_offset: computed offset returned by reference.
1005 *
1006 * Compute/Claim a new offset for this EP.
1007 */
scif_get_window_offset(struct scif_endpt * ep,int flags,s64 offset,int num_pages,s64 * out_offset)1008 int scif_get_window_offset(struct scif_endpt *ep, int flags, s64 offset,
1009 int num_pages, s64 *out_offset)
1010 {
1011 s64 page_index;
1012 struct iova *iova_ptr;
1013 int err = 0;
1014
1015 if (flags & SCIF_MAP_FIXED) {
1016 page_index = SCIF_IOVA_PFN(offset);
1017 iova_ptr = reserve_iova(&ep->rma_info.iovad, page_index,
1018 page_index + num_pages - 1);
1019 if (!iova_ptr)
1020 err = -EADDRINUSE;
1021 } else {
1022 iova_ptr = alloc_iova(&ep->rma_info.iovad, num_pages,
1023 SCIF_DMA_63BIT_PFN - 1, 0);
1024 if (!iova_ptr)
1025 err = -ENOMEM;
1026 }
1027 if (!err)
1028 *out_offset = (iova_ptr->pfn_lo) << PAGE_SHIFT;
1029 return err;
1030 }
1031
1032 /**
1033 * scif_free_window_offset:
1034 * @ep: end point descriptor
1035 * @window: registration window
1036 * @offset: Offset to be freed
1037 *
1038 * Free offset for this EP. The callee is supposed to grab
1039 * the RMA mutex before calling this API.
1040 */
scif_free_window_offset(struct scif_endpt * ep,struct scif_window * window,s64 offset)1041 void scif_free_window_offset(struct scif_endpt *ep,
1042 struct scif_window *window, s64 offset)
1043 {
1044 if ((window && !window->offset_freed) || !window) {
1045 free_iova(&ep->rma_info.iovad, offset >> PAGE_SHIFT);
1046 if (window)
1047 window->offset_freed = true;
1048 }
1049 }
1050
1051 /**
1052 * scif_alloc_req: Respond to SCIF_ALLOC_REQ interrupt message
1053 * @msg: Interrupt message
1054 *
1055 * Remote side is requesting a memory allocation.
1056 */
scif_alloc_req(struct scif_dev * scifdev,struct scifmsg * msg)1057 void scif_alloc_req(struct scif_dev *scifdev, struct scifmsg *msg)
1058 {
1059 int err;
1060 struct scif_window *window = NULL;
1061 int nr_pages = msg->payload[1];
1062
1063 window = scif_create_remote_window(scifdev, nr_pages);
1064 if (!window) {
1065 err = -ENOMEM;
1066 goto error;
1067 }
1068
1069 /* The peer's allocation request is granted */
1070 msg->uop = SCIF_ALLOC_GNT;
1071 msg->payload[0] = (u64)window;
1072 msg->payload[1] = window->mapped_offset;
1073 err = scif_nodeqp_send(scifdev, msg);
1074 if (err)
1075 scif_destroy_remote_window(window);
1076 return;
1077 error:
1078 /* The peer's allocation request is rejected */
1079 dev_err(&scifdev->sdev->dev,
1080 "%s %d error %d alloc_ptr %p nr_pages 0x%x\n",
1081 __func__, __LINE__, err, window, nr_pages);
1082 msg->uop = SCIF_ALLOC_REJ;
1083 scif_nodeqp_send(scifdev, msg);
1084 }
1085
1086 /**
1087 * scif_alloc_gnt_rej: Respond to SCIF_ALLOC_GNT/REJ interrupt message
1088 * @msg: Interrupt message
1089 *
1090 * Remote side responded to a memory allocation.
1091 */
scif_alloc_gnt_rej(struct scif_dev * scifdev,struct scifmsg * msg)1092 void scif_alloc_gnt_rej(struct scif_dev *scifdev, struct scifmsg *msg)
1093 {
1094 struct scif_allocmsg *handle = (struct scif_allocmsg *)msg->payload[2];
1095 struct scif_window *window = container_of(handle, struct scif_window,
1096 alloc_handle);
1097 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1098
1099 mutex_lock(&ep->rma_info.rma_lock);
1100 handle->vaddr = msg->payload[0];
1101 handle->phys_addr = msg->payload[1];
1102 if (msg->uop == SCIF_ALLOC_GNT)
1103 handle->state = OP_COMPLETED;
1104 else
1105 handle->state = OP_FAILED;
1106 wake_up(&handle->allocwq);
1107 mutex_unlock(&ep->rma_info.rma_lock);
1108 }
1109
1110 /**
1111 * scif_free_virt: Respond to SCIF_FREE_VIRT interrupt message
1112 * @msg: Interrupt message
1113 *
1114 * Free up memory kmalloc'd earlier.
1115 */
scif_free_virt(struct scif_dev * scifdev,struct scifmsg * msg)1116 void scif_free_virt(struct scif_dev *scifdev, struct scifmsg *msg)
1117 {
1118 struct scif_window *window = (struct scif_window *)msg->payload[1];
1119
1120 scif_destroy_remote_window(window);
1121 }
1122
1123 static void
scif_fixup_aper_base(struct scif_dev * dev,struct scif_window * window)1124 scif_fixup_aper_base(struct scif_dev *dev, struct scif_window *window)
1125 {
1126 int j;
1127 struct scif_hw_dev *sdev = dev->sdev;
1128 phys_addr_t apt_base = 0;
1129
1130 /*
1131 * Add the aperture base if the DMA address is not card relative
1132 * since the DMA addresses need to be an offset into the bar
1133 */
1134 if (!scifdev_self(dev) && window->type == SCIF_WINDOW_PEER &&
1135 sdev->aper && !sdev->card_rel_da)
1136 apt_base = sdev->aper->pa;
1137 else
1138 return;
1139
1140 for (j = 0; j < window->nr_contig_chunks; j++) {
1141 if (window->num_pages[j])
1142 window->dma_addr[j] += apt_base;
1143 else
1144 break;
1145 }
1146 }
1147
1148 /**
1149 * scif_recv_reg: Respond to SCIF_REGISTER interrupt message
1150 * @msg: Interrupt message
1151 *
1152 * Update remote window list with a new registered window.
1153 */
scif_recv_reg(struct scif_dev * scifdev,struct scifmsg * msg)1154 void scif_recv_reg(struct scif_dev *scifdev, struct scifmsg *msg)
1155 {
1156 struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
1157 struct scif_window *window =
1158 (struct scif_window *)msg->payload[1];
1159
1160 mutex_lock(&ep->rma_info.rma_lock);
1161 spin_lock(&ep->lock);
1162 if (ep->state == SCIFEP_CONNECTED) {
1163 msg->uop = SCIF_REGISTER_ACK;
1164 scif_nodeqp_send(ep->remote_dev, msg);
1165 scif_fixup_aper_base(ep->remote_dev, window);
1166 /* No further failures expected. Insert new window */
1167 scif_insert_window(window, &ep->rma_info.remote_reg_list);
1168 } else {
1169 msg->uop = SCIF_REGISTER_NACK;
1170 scif_nodeqp_send(ep->remote_dev, msg);
1171 }
1172 spin_unlock(&ep->lock);
1173 mutex_unlock(&ep->rma_info.rma_lock);
1174 /* free up any lookup resources now that page lists are transferred */
1175 scif_destroy_remote_lookup(ep->remote_dev, window);
1176 /*
1177 * We could not insert the window but we need to
1178 * destroy the window.
1179 */
1180 if (msg->uop == SCIF_REGISTER_NACK)
1181 scif_destroy_remote_window(window);
1182 }
1183
1184 /**
1185 * scif_recv_unreg: Respond to SCIF_UNREGISTER interrupt message
1186 * @msg: Interrupt message
1187 *
1188 * Remove window from remote registration list;
1189 */
scif_recv_unreg(struct scif_dev * scifdev,struct scifmsg * msg)1190 void scif_recv_unreg(struct scif_dev *scifdev, struct scifmsg *msg)
1191 {
1192 struct scif_rma_req req;
1193 struct scif_window *window = NULL;
1194 struct scif_window *recv_window =
1195 (struct scif_window *)msg->payload[0];
1196 struct scif_endpt *ep;
1197 int del_window = 0;
1198
1199 ep = (struct scif_endpt *)recv_window->ep;
1200 req.out_window = &window;
1201 req.offset = recv_window->offset;
1202 req.prot = 0;
1203 req.nr_bytes = recv_window->nr_pages << PAGE_SHIFT;
1204 req.type = SCIF_WINDOW_FULL;
1205 req.head = &ep->rma_info.remote_reg_list;
1206 msg->payload[0] = ep->remote_ep;
1207
1208 mutex_lock(&ep->rma_info.rma_lock);
1209 /* Does a valid window exist? */
1210 if (scif_query_window(&req)) {
1211 dev_err(&scifdev->sdev->dev,
1212 "%s %d -ENXIO\n", __func__, __LINE__);
1213 msg->uop = SCIF_UNREGISTER_ACK;
1214 goto error;
1215 }
1216 if (window) {
1217 if (window->ref_count)
1218 scif_put_window(window, window->nr_pages);
1219 else
1220 dev_err(&scifdev->sdev->dev,
1221 "%s %d ref count should be +ve\n",
1222 __func__, __LINE__);
1223 window->unreg_state = OP_COMPLETED;
1224 if (!window->ref_count) {
1225 msg->uop = SCIF_UNREGISTER_ACK;
1226 atomic_inc(&ep->rma_info.tw_refcount);
1227 ep->rma_info.async_list_del = 1;
1228 list_del_init(&window->list);
1229 del_window = 1;
1230 } else {
1231 /* NACK! There are valid references to this window */
1232 msg->uop = SCIF_UNREGISTER_NACK;
1233 }
1234 } else {
1235 /* The window did not make its way to the list at all. ACK */
1236 msg->uop = SCIF_UNREGISTER_ACK;
1237 scif_destroy_remote_window(recv_window);
1238 }
1239 error:
1240 mutex_unlock(&ep->rma_info.rma_lock);
1241 if (del_window)
1242 scif_drain_dma_intr(ep->remote_dev->sdev,
1243 ep->rma_info.dma_chan);
1244 scif_nodeqp_send(ep->remote_dev, msg);
1245 if (del_window)
1246 scif_queue_for_cleanup(window, &scif_info.rma);
1247 }
1248
1249 /**
1250 * scif_recv_reg_ack: Respond to SCIF_REGISTER_ACK interrupt message
1251 * @msg: Interrupt message
1252 *
1253 * Wake up the window waiting to complete registration.
1254 */
scif_recv_reg_ack(struct scif_dev * scifdev,struct scifmsg * msg)1255 void scif_recv_reg_ack(struct scif_dev *scifdev, struct scifmsg *msg)
1256 {
1257 struct scif_window *window =
1258 (struct scif_window *)msg->payload[2];
1259 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1260
1261 mutex_lock(&ep->rma_info.rma_lock);
1262 window->reg_state = OP_COMPLETED;
1263 wake_up(&window->regwq);
1264 mutex_unlock(&ep->rma_info.rma_lock);
1265 }
1266
1267 /**
1268 * scif_recv_reg_nack: Respond to SCIF_REGISTER_NACK interrupt message
1269 * @msg: Interrupt message
1270 *
1271 * Wake up the window waiting to inform it that registration
1272 * cannot be completed.
1273 */
scif_recv_reg_nack(struct scif_dev * scifdev,struct scifmsg * msg)1274 void scif_recv_reg_nack(struct scif_dev *scifdev, struct scifmsg *msg)
1275 {
1276 struct scif_window *window =
1277 (struct scif_window *)msg->payload[2];
1278 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1279
1280 mutex_lock(&ep->rma_info.rma_lock);
1281 window->reg_state = OP_FAILED;
1282 wake_up(&window->regwq);
1283 mutex_unlock(&ep->rma_info.rma_lock);
1284 }
1285
1286 /**
1287 * scif_recv_unreg_ack: Respond to SCIF_UNREGISTER_ACK interrupt message
1288 * @msg: Interrupt message
1289 *
1290 * Wake up the window waiting to complete unregistration.
1291 */
scif_recv_unreg_ack(struct scif_dev * scifdev,struct scifmsg * msg)1292 void scif_recv_unreg_ack(struct scif_dev *scifdev, struct scifmsg *msg)
1293 {
1294 struct scif_window *window =
1295 (struct scif_window *)msg->payload[1];
1296 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1297
1298 mutex_lock(&ep->rma_info.rma_lock);
1299 window->unreg_state = OP_COMPLETED;
1300 wake_up(&window->unregwq);
1301 mutex_unlock(&ep->rma_info.rma_lock);
1302 }
1303
1304 /**
1305 * scif_recv_unreg_nack: Respond to SCIF_UNREGISTER_NACK interrupt message
1306 * @msg: Interrupt message
1307 *
1308 * Wake up the window waiting to inform it that unregistration
1309 * cannot be completed immediately.
1310 */
scif_recv_unreg_nack(struct scif_dev * scifdev,struct scifmsg * msg)1311 void scif_recv_unreg_nack(struct scif_dev *scifdev, struct scifmsg *msg)
1312 {
1313 struct scif_window *window =
1314 (struct scif_window *)msg->payload[1];
1315 struct scif_endpt *ep = (struct scif_endpt *)window->ep;
1316
1317 mutex_lock(&ep->rma_info.rma_lock);
1318 window->unreg_state = OP_FAILED;
1319 wake_up(&window->unregwq);
1320 mutex_unlock(&ep->rma_info.rma_lock);
1321 }
1322
__scif_pin_pages(void * addr,size_t len,int * out_prot,int map_flags,scif_pinned_pages_t * pages)1323 int __scif_pin_pages(void *addr, size_t len, int *out_prot,
1324 int map_flags, scif_pinned_pages_t *pages)
1325 {
1326 struct scif_pinned_pages *pinned_pages;
1327 int nr_pages, err = 0, i;
1328 bool vmalloc_addr = false;
1329 bool try_upgrade = false;
1330 int prot = *out_prot;
1331 int ulimit = 0;
1332 struct mm_struct *mm = NULL;
1333
1334 /* Unsupported flags */
1335 if (map_flags & ~(SCIF_MAP_KERNEL | SCIF_MAP_ULIMIT))
1336 return -EINVAL;
1337 ulimit = !!(map_flags & SCIF_MAP_ULIMIT);
1338
1339 /* Unsupported protection requested */
1340 if (prot & ~(SCIF_PROT_READ | SCIF_PROT_WRITE))
1341 return -EINVAL;
1342
1343 /* addr/len must be page aligned. len should be non zero */
1344 if (!len ||
1345 (ALIGN((u64)addr, PAGE_SIZE) != (u64)addr) ||
1346 (ALIGN((u64)len, PAGE_SIZE) != (u64)len))
1347 return -EINVAL;
1348
1349 might_sleep();
1350
1351 nr_pages = len >> PAGE_SHIFT;
1352
1353 /* Allocate a set of pinned pages */
1354 pinned_pages = scif_create_pinned_pages(nr_pages, prot);
1355 if (!pinned_pages)
1356 return -ENOMEM;
1357
1358 if (map_flags & SCIF_MAP_KERNEL) {
1359 if (is_vmalloc_addr(addr))
1360 vmalloc_addr = true;
1361
1362 for (i = 0; i < nr_pages; i++) {
1363 if (vmalloc_addr)
1364 pinned_pages->pages[i] =
1365 vmalloc_to_page(addr + (i * PAGE_SIZE));
1366 else
1367 pinned_pages->pages[i] =
1368 virt_to_page(addr + (i * PAGE_SIZE));
1369 }
1370 pinned_pages->nr_pages = nr_pages;
1371 pinned_pages->map_flags = SCIF_MAP_KERNEL;
1372 } else {
1373 /*
1374 * SCIF supports registration caching. If a registration has
1375 * been requested with read only permissions, then we try
1376 * to pin the pages with RW permissions so that a subsequent
1377 * transfer with RW permission can hit the cache instead of
1378 * invalidating it. If the upgrade fails with RW then we
1379 * revert back to R permission and retry
1380 */
1381 if (prot == SCIF_PROT_READ)
1382 try_upgrade = true;
1383 prot |= SCIF_PROT_WRITE;
1384 retry:
1385 mm = current->mm;
1386 down_write(&mm->mmap_sem);
1387 if (ulimit) {
1388 err = __scif_check_inc_pinned_vm(mm, nr_pages);
1389 if (err) {
1390 up_write(&mm->mmap_sem);
1391 pinned_pages->nr_pages = 0;
1392 goto error_unmap;
1393 }
1394 }
1395
1396 pinned_pages->nr_pages = get_user_pages(
1397 (u64)addr,
1398 nr_pages,
1399 (prot & SCIF_PROT_WRITE) ? FOLL_WRITE : 0,
1400 pinned_pages->pages,
1401 NULL);
1402 up_write(&mm->mmap_sem);
1403 if (nr_pages != pinned_pages->nr_pages) {
1404 if (try_upgrade) {
1405 if (ulimit)
1406 __scif_dec_pinned_vm_lock(mm,
1407 nr_pages, 0);
1408 /* Roll back any pinned pages */
1409 for (i = 0; i < pinned_pages->nr_pages; i++) {
1410 if (pinned_pages->pages[i])
1411 put_page(
1412 pinned_pages->pages[i]);
1413 }
1414 prot &= ~SCIF_PROT_WRITE;
1415 try_upgrade = false;
1416 goto retry;
1417 }
1418 }
1419 pinned_pages->map_flags = 0;
1420 }
1421
1422 if (pinned_pages->nr_pages < nr_pages) {
1423 err = -EFAULT;
1424 pinned_pages->nr_pages = nr_pages;
1425 goto dec_pinned;
1426 }
1427
1428 *out_prot = prot;
1429 atomic_set(&pinned_pages->ref_count, 1);
1430 *pages = pinned_pages;
1431 return err;
1432 dec_pinned:
1433 if (ulimit)
1434 __scif_dec_pinned_vm_lock(mm, nr_pages, 0);
1435 /* Something went wrong! Rollback */
1436 error_unmap:
1437 pinned_pages->nr_pages = nr_pages;
1438 scif_destroy_pinned_pages(pinned_pages);
1439 *pages = NULL;
1440 dev_dbg(scif_info.mdev.this_device,
1441 "%s %d err %d len 0x%lx\n", __func__, __LINE__, err, len);
1442 return err;
1443 }
1444
scif_pin_pages(void * addr,size_t len,int prot,int map_flags,scif_pinned_pages_t * pages)1445 int scif_pin_pages(void *addr, size_t len, int prot,
1446 int map_flags, scif_pinned_pages_t *pages)
1447 {
1448 return __scif_pin_pages(addr, len, &prot, map_flags, pages);
1449 }
1450 EXPORT_SYMBOL_GPL(scif_pin_pages);
1451
scif_unpin_pages(scif_pinned_pages_t pinned_pages)1452 int scif_unpin_pages(scif_pinned_pages_t pinned_pages)
1453 {
1454 int err = 0, ret;
1455
1456 if (!pinned_pages || SCIFEP_MAGIC != pinned_pages->magic)
1457 return -EINVAL;
1458
1459 ret = atomic_sub_return(1, &pinned_pages->ref_count);
1460 if (ret < 0) {
1461 dev_err(scif_info.mdev.this_device,
1462 "%s %d scif_unpin_pages called without pinning? rc %d\n",
1463 __func__, __LINE__, ret);
1464 return -EINVAL;
1465 }
1466 /*
1467 * Destroy the window if the ref count for this set of pinned
1468 * pages has dropped to zero. If it is positive then there is
1469 * a valid registered window which is backed by these pages and
1470 * it will be destroyed once all such windows are unregistered.
1471 */
1472 if (!ret)
1473 err = scif_destroy_pinned_pages(pinned_pages);
1474
1475 return err;
1476 }
1477 EXPORT_SYMBOL_GPL(scif_unpin_pages);
1478
1479 static inline void
scif_insert_local_window(struct scif_window * window,struct scif_endpt * ep)1480 scif_insert_local_window(struct scif_window *window, struct scif_endpt *ep)
1481 {
1482 mutex_lock(&ep->rma_info.rma_lock);
1483 scif_insert_window(window, &ep->rma_info.reg_list);
1484 mutex_unlock(&ep->rma_info.rma_lock);
1485 }
1486
scif_register_pinned_pages(scif_epd_t epd,scif_pinned_pages_t pinned_pages,off_t offset,int map_flags)1487 off_t scif_register_pinned_pages(scif_epd_t epd,
1488 scif_pinned_pages_t pinned_pages,
1489 off_t offset, int map_flags)
1490 {
1491 struct scif_endpt *ep = (struct scif_endpt *)epd;
1492 s64 computed_offset;
1493 struct scif_window *window;
1494 int err;
1495 size_t len;
1496 struct device *spdev;
1497
1498 /* Unsupported flags */
1499 if (map_flags & ~SCIF_MAP_FIXED)
1500 return -EINVAL;
1501
1502 len = pinned_pages->nr_pages << PAGE_SHIFT;
1503
1504 /*
1505 * Offset is not page aligned/negative or offset+len
1506 * wraps around with SCIF_MAP_FIXED.
1507 */
1508 if ((map_flags & SCIF_MAP_FIXED) &&
1509 ((ALIGN(offset, PAGE_SIZE) != offset) ||
1510 (offset < 0) ||
1511 (len > LONG_MAX - offset)))
1512 return -EINVAL;
1513
1514 might_sleep();
1515
1516 err = scif_verify_epd(ep);
1517 if (err)
1518 return err;
1519 /*
1520 * It is an error to pass pinned_pages to scif_register_pinned_pages()
1521 * after calling scif_unpin_pages().
1522 */
1523 if (!atomic_add_unless(&pinned_pages->ref_count, 1, 0))
1524 return -EINVAL;
1525
1526 /* Compute the offset for this registration */
1527 err = scif_get_window_offset(ep, map_flags, offset,
1528 len, &computed_offset);
1529 if (err) {
1530 atomic_sub(1, &pinned_pages->ref_count);
1531 return err;
1532 }
1533
1534 /* Allocate and prepare self registration window */
1535 window = scif_create_window(ep, pinned_pages->nr_pages,
1536 computed_offset, false);
1537 if (!window) {
1538 atomic_sub(1, &pinned_pages->ref_count);
1539 scif_free_window_offset(ep, NULL, computed_offset);
1540 return -ENOMEM;
1541 }
1542
1543 window->pinned_pages = pinned_pages;
1544 window->nr_pages = pinned_pages->nr_pages;
1545 window->prot = pinned_pages->prot;
1546
1547 spdev = scif_get_peer_dev(ep->remote_dev);
1548 if (IS_ERR(spdev)) {
1549 err = PTR_ERR(spdev);
1550 scif_destroy_window(ep, window);
1551 return err;
1552 }
1553 err = scif_send_alloc_request(ep, window);
1554 if (err) {
1555 dev_err(&ep->remote_dev->sdev->dev,
1556 "%s %d err %d\n", __func__, __LINE__, err);
1557 goto error_unmap;
1558 }
1559
1560 /* Prepare the remote registration window */
1561 err = scif_prep_remote_window(ep, window);
1562 if (err) {
1563 dev_err(&ep->remote_dev->sdev->dev,
1564 "%s %d err %d\n", __func__, __LINE__, err);
1565 goto error_unmap;
1566 }
1567
1568 /* Tell the peer about the new window */
1569 err = scif_send_scif_register(ep, window);
1570 if (err) {
1571 dev_err(&ep->remote_dev->sdev->dev,
1572 "%s %d err %d\n", __func__, __LINE__, err);
1573 goto error_unmap;
1574 }
1575
1576 scif_put_peer_dev(spdev);
1577 /* No further failures expected. Insert new window */
1578 scif_insert_local_window(window, ep);
1579 return computed_offset;
1580 error_unmap:
1581 scif_destroy_window(ep, window);
1582 scif_put_peer_dev(spdev);
1583 dev_err(&ep->remote_dev->sdev->dev,
1584 "%s %d err %d\n", __func__, __LINE__, err);
1585 return err;
1586 }
1587 EXPORT_SYMBOL_GPL(scif_register_pinned_pages);
1588
scif_register(scif_epd_t epd,void * addr,size_t len,off_t offset,int prot,int map_flags)1589 off_t scif_register(scif_epd_t epd, void *addr, size_t len, off_t offset,
1590 int prot, int map_flags)
1591 {
1592 scif_pinned_pages_t pinned_pages;
1593 off_t err;
1594 struct scif_endpt *ep = (struct scif_endpt *)epd;
1595 s64 computed_offset;
1596 struct scif_window *window;
1597 struct mm_struct *mm = NULL;
1598 struct device *spdev;
1599
1600 dev_dbg(scif_info.mdev.this_device,
1601 "SCIFAPI register: ep %p addr %p len 0x%lx offset 0x%lx prot 0x%x map_flags 0x%x\n",
1602 epd, addr, len, offset, prot, map_flags);
1603 /* Unsupported flags */
1604 if (map_flags & ~(SCIF_MAP_FIXED | SCIF_MAP_KERNEL))
1605 return -EINVAL;
1606
1607 /*
1608 * Offset is not page aligned/negative or offset+len
1609 * wraps around with SCIF_MAP_FIXED.
1610 */
1611 if ((map_flags & SCIF_MAP_FIXED) &&
1612 ((ALIGN(offset, PAGE_SIZE) != offset) ||
1613 (offset < 0) ||
1614 (len > LONG_MAX - offset)))
1615 return -EINVAL;
1616
1617 /* Unsupported protection requested */
1618 if (prot & ~(SCIF_PROT_READ | SCIF_PROT_WRITE))
1619 return -EINVAL;
1620
1621 /* addr/len must be page aligned. len should be non zero */
1622 if (!len || (ALIGN((u64)addr, PAGE_SIZE) != (u64)addr) ||
1623 (ALIGN(len, PAGE_SIZE) != len))
1624 return -EINVAL;
1625
1626 might_sleep();
1627
1628 err = scif_verify_epd(ep);
1629 if (err)
1630 return err;
1631
1632 /* Compute the offset for this registration */
1633 err = scif_get_window_offset(ep, map_flags, offset,
1634 len >> PAGE_SHIFT, &computed_offset);
1635 if (err)
1636 return err;
1637
1638 spdev = scif_get_peer_dev(ep->remote_dev);
1639 if (IS_ERR(spdev)) {
1640 err = PTR_ERR(spdev);
1641 scif_free_window_offset(ep, NULL, computed_offset);
1642 return err;
1643 }
1644 /* Allocate and prepare self registration window */
1645 window = scif_create_window(ep, len >> PAGE_SHIFT,
1646 computed_offset, false);
1647 if (!window) {
1648 scif_free_window_offset(ep, NULL, computed_offset);
1649 scif_put_peer_dev(spdev);
1650 return -ENOMEM;
1651 }
1652
1653 window->nr_pages = len >> PAGE_SHIFT;
1654
1655 err = scif_send_alloc_request(ep, window);
1656 if (err) {
1657 scif_destroy_incomplete_window(ep, window);
1658 scif_put_peer_dev(spdev);
1659 return err;
1660 }
1661
1662 if (!(map_flags & SCIF_MAP_KERNEL)) {
1663 mm = __scif_acquire_mm();
1664 map_flags |= SCIF_MAP_ULIMIT;
1665 }
1666 /* Pin down the pages */
1667 err = __scif_pin_pages(addr, len, &prot,
1668 map_flags & (SCIF_MAP_KERNEL | SCIF_MAP_ULIMIT),
1669 &pinned_pages);
1670 if (err) {
1671 scif_destroy_incomplete_window(ep, window);
1672 __scif_release_mm(mm);
1673 goto error;
1674 }
1675
1676 window->pinned_pages = pinned_pages;
1677 window->prot = pinned_pages->prot;
1678 window->mm = mm;
1679
1680 /* Prepare the remote registration window */
1681 err = scif_prep_remote_window(ep, window);
1682 if (err) {
1683 dev_err(&ep->remote_dev->sdev->dev,
1684 "%s %d err %ld\n", __func__, __LINE__, err);
1685 goto error_unmap;
1686 }
1687
1688 /* Tell the peer about the new window */
1689 err = scif_send_scif_register(ep, window);
1690 if (err) {
1691 dev_err(&ep->remote_dev->sdev->dev,
1692 "%s %d err %ld\n", __func__, __LINE__, err);
1693 goto error_unmap;
1694 }
1695
1696 scif_put_peer_dev(spdev);
1697 /* No further failures expected. Insert new window */
1698 scif_insert_local_window(window, ep);
1699 dev_dbg(&ep->remote_dev->sdev->dev,
1700 "SCIFAPI register: ep %p addr %p len 0x%lx computed_offset 0x%llx\n",
1701 epd, addr, len, computed_offset);
1702 return computed_offset;
1703 error_unmap:
1704 scif_destroy_window(ep, window);
1705 error:
1706 scif_put_peer_dev(spdev);
1707 dev_err(&ep->remote_dev->sdev->dev,
1708 "%s %d err %ld\n", __func__, __LINE__, err);
1709 return err;
1710 }
1711 EXPORT_SYMBOL_GPL(scif_register);
1712
1713 int
scif_unregister(scif_epd_t epd,off_t offset,size_t len)1714 scif_unregister(scif_epd_t epd, off_t offset, size_t len)
1715 {
1716 struct scif_endpt *ep = (struct scif_endpt *)epd;
1717 struct scif_window *window = NULL;
1718 struct scif_rma_req req;
1719 int nr_pages, err;
1720 struct device *spdev;
1721
1722 dev_dbg(scif_info.mdev.this_device,
1723 "SCIFAPI unregister: ep %p offset 0x%lx len 0x%lx\n",
1724 ep, offset, len);
1725 /* len must be page aligned. len should be non zero */
1726 if (!len ||
1727 (ALIGN((u64)len, PAGE_SIZE) != (u64)len))
1728 return -EINVAL;
1729
1730 /* Offset is not page aligned or offset+len wraps around */
1731 if ((ALIGN(offset, PAGE_SIZE) != offset) ||
1732 (offset < 0) ||
1733 (len > LONG_MAX - offset))
1734 return -EINVAL;
1735
1736 err = scif_verify_epd(ep);
1737 if (err)
1738 return err;
1739
1740 might_sleep();
1741 nr_pages = len >> PAGE_SHIFT;
1742
1743 req.out_window = &window;
1744 req.offset = offset;
1745 req.prot = 0;
1746 req.nr_bytes = len;
1747 req.type = SCIF_WINDOW_FULL;
1748 req.head = &ep->rma_info.reg_list;
1749
1750 spdev = scif_get_peer_dev(ep->remote_dev);
1751 if (IS_ERR(spdev)) {
1752 err = PTR_ERR(spdev);
1753 return err;
1754 }
1755 mutex_lock(&ep->rma_info.rma_lock);
1756 /* Does a valid window exist? */
1757 err = scif_query_window(&req);
1758 if (err) {
1759 dev_err(&ep->remote_dev->sdev->dev,
1760 "%s %d err %d\n", __func__, __LINE__, err);
1761 goto error;
1762 }
1763 /* Unregister all the windows in this range */
1764 err = scif_rma_list_unregister(window, offset, nr_pages);
1765 if (err)
1766 dev_err(&ep->remote_dev->sdev->dev,
1767 "%s %d err %d\n", __func__, __LINE__, err);
1768 error:
1769 mutex_unlock(&ep->rma_info.rma_lock);
1770 scif_put_peer_dev(spdev);
1771 return err;
1772 }
1773 EXPORT_SYMBOL_GPL(scif_unregister);
1774