1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3 * Copyright(c) 2020 Cornelis Networks, Inc.
4 * Copyright(c) 2015-2018 Intel Corporation.
5 */
6 #include <asm/page.h>
7 #include <linux/string.h>
8
9 #include "mmu_rb.h"
10 #include "user_exp_rcv.h"
11 #include "trace.h"
12
13 static void unlock_exp_tids(struct hfi1_ctxtdata *uctxt,
14 struct exp_tid_set *set,
15 struct hfi1_filedata *fd);
16 static u32 find_phys_blocks(struct tid_user_buf *tidbuf, unsigned int npages);
17 static int set_rcvarray_entry(struct hfi1_filedata *fd,
18 struct tid_user_buf *tbuf,
19 u32 rcventry, struct tid_group *grp,
20 u16 pageidx, unsigned int npages);
21 static void cacheless_tid_rb_remove(struct hfi1_filedata *fdata,
22 struct tid_rb_node *tnode);
23 static bool tid_rb_invalidate(struct mmu_interval_notifier *mni,
24 const struct mmu_notifier_range *range,
25 unsigned long cur_seq);
26 static bool tid_cover_invalidate(struct mmu_interval_notifier *mni,
27 const struct mmu_notifier_range *range,
28 unsigned long cur_seq);
29 static int program_rcvarray(struct hfi1_filedata *fd, struct tid_user_buf *,
30 struct tid_group *grp, u16 count,
31 u32 *tidlist, unsigned int *tididx,
32 unsigned int *pmapped);
33 static int unprogram_rcvarray(struct hfi1_filedata *fd, u32 tidinfo);
34 static void __clear_tid_node(struct hfi1_filedata *fd,
35 struct tid_rb_node *node);
36 static void clear_tid_node(struct hfi1_filedata *fd, struct tid_rb_node *node);
37
38 static const struct mmu_interval_notifier_ops tid_mn_ops = {
39 .invalidate = tid_rb_invalidate,
40 };
41 static const struct mmu_interval_notifier_ops tid_cover_ops = {
42 .invalidate = tid_cover_invalidate,
43 };
44
45 /*
46 * Initialize context and file private data needed for Expected
47 * receive caching. This needs to be done after the context has
48 * been configured with the eager/expected RcvEntry counts.
49 */
hfi1_user_exp_rcv_init(struct hfi1_filedata * fd,struct hfi1_ctxtdata * uctxt)50 int hfi1_user_exp_rcv_init(struct hfi1_filedata *fd,
51 struct hfi1_ctxtdata *uctxt)
52 {
53 int ret = 0;
54
55 fd->entry_to_rb = kcalloc(uctxt->expected_count,
56 sizeof(struct rb_node *),
57 GFP_KERNEL);
58 if (!fd->entry_to_rb)
59 return -ENOMEM;
60
61 if (!HFI1_CAP_UGET_MASK(uctxt->flags, TID_UNMAP)) {
62 fd->invalid_tid_idx = 0;
63 fd->invalid_tids = kcalloc(uctxt->expected_count,
64 sizeof(*fd->invalid_tids),
65 GFP_KERNEL);
66 if (!fd->invalid_tids) {
67 kfree(fd->entry_to_rb);
68 fd->entry_to_rb = NULL;
69 return -ENOMEM;
70 }
71 fd->use_mn = true;
72 }
73
74 /*
75 * PSM does not have a good way to separate, count, and
76 * effectively enforce a limit on RcvArray entries used by
77 * subctxts (when context sharing is used) when TID caching
78 * is enabled. To help with that, we calculate a per-process
79 * RcvArray entry share and enforce that.
80 * If TID caching is not in use, PSM deals with usage on its
81 * own. In that case, we allow any subctxt to take all of the
82 * entries.
83 *
84 * Make sure that we set the tid counts only after successful
85 * init.
86 */
87 spin_lock(&fd->tid_lock);
88 if (uctxt->subctxt_cnt && fd->use_mn) {
89 u16 remainder;
90
91 fd->tid_limit = uctxt->expected_count / uctxt->subctxt_cnt;
92 remainder = uctxt->expected_count % uctxt->subctxt_cnt;
93 if (remainder && fd->subctxt < remainder)
94 fd->tid_limit++;
95 } else {
96 fd->tid_limit = uctxt->expected_count;
97 }
98 spin_unlock(&fd->tid_lock);
99
100 return ret;
101 }
102
hfi1_user_exp_rcv_free(struct hfi1_filedata * fd)103 void hfi1_user_exp_rcv_free(struct hfi1_filedata *fd)
104 {
105 struct hfi1_ctxtdata *uctxt = fd->uctxt;
106
107 mutex_lock(&uctxt->exp_mutex);
108 if (!EXP_TID_SET_EMPTY(uctxt->tid_full_list))
109 unlock_exp_tids(uctxt, &uctxt->tid_full_list, fd);
110 if (!EXP_TID_SET_EMPTY(uctxt->tid_used_list))
111 unlock_exp_tids(uctxt, &uctxt->tid_used_list, fd);
112 mutex_unlock(&uctxt->exp_mutex);
113
114 kfree(fd->invalid_tids);
115 fd->invalid_tids = NULL;
116
117 kfree(fd->entry_to_rb);
118 fd->entry_to_rb = NULL;
119 }
120
121 /*
122 * Release pinned receive buffer pages.
123 *
124 * @mapped: true if the pages have been DMA mapped. false otherwise.
125 * @idx: Index of the first page to unpin.
126 * @npages: No of pages to unpin.
127 *
128 * If the pages have been DMA mapped (indicated by mapped parameter), their
129 * info will be passed via a struct tid_rb_node. If they haven't been mapped,
130 * their info will be passed via a struct tid_user_buf.
131 */
unpin_rcv_pages(struct hfi1_filedata * fd,struct tid_user_buf * tidbuf,struct tid_rb_node * node,unsigned int idx,unsigned int npages,bool mapped)132 static void unpin_rcv_pages(struct hfi1_filedata *fd,
133 struct tid_user_buf *tidbuf,
134 struct tid_rb_node *node,
135 unsigned int idx,
136 unsigned int npages,
137 bool mapped)
138 {
139 struct page **pages;
140 struct hfi1_devdata *dd = fd->uctxt->dd;
141 struct mm_struct *mm;
142
143 if (mapped) {
144 dma_unmap_single(&dd->pcidev->dev, node->dma_addr,
145 node->npages * PAGE_SIZE, DMA_FROM_DEVICE);
146 pages = &node->pages[idx];
147 mm = mm_from_tid_node(node);
148 } else {
149 pages = &tidbuf->pages[idx];
150 mm = current->mm;
151 }
152 hfi1_release_user_pages(mm, pages, npages, mapped);
153 fd->tid_n_pinned -= npages;
154 }
155
156 /*
157 * Pin receive buffer pages.
158 */
pin_rcv_pages(struct hfi1_filedata * fd,struct tid_user_buf * tidbuf)159 static int pin_rcv_pages(struct hfi1_filedata *fd, struct tid_user_buf *tidbuf)
160 {
161 int pinned;
162 unsigned int npages = tidbuf->npages;
163 unsigned long vaddr = tidbuf->vaddr;
164 struct page **pages = NULL;
165 struct hfi1_devdata *dd = fd->uctxt->dd;
166
167 if (npages > fd->uctxt->expected_count) {
168 dd_dev_err(dd, "Expected buffer too big\n");
169 return -EINVAL;
170 }
171
172 /* Allocate the array of struct page pointers needed for pinning */
173 pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
174 if (!pages)
175 return -ENOMEM;
176
177 /*
178 * Pin all the pages of the user buffer. If we can't pin all the
179 * pages, accept the amount pinned so far and program only that.
180 * User space knows how to deal with partially programmed buffers.
181 */
182 if (!hfi1_can_pin_pages(dd, current->mm, fd->tid_n_pinned, npages)) {
183 kfree(pages);
184 return -ENOMEM;
185 }
186
187 pinned = hfi1_acquire_user_pages(current->mm, vaddr, npages, true, pages);
188 if (pinned <= 0) {
189 kfree(pages);
190 return pinned;
191 }
192 tidbuf->pages = pages;
193 fd->tid_n_pinned += pinned;
194 return pinned;
195 }
196
197 /*
198 * RcvArray entry allocation for Expected Receives is done by the
199 * following algorithm:
200 *
201 * The context keeps 3 lists of groups of RcvArray entries:
202 * 1. List of empty groups - tid_group_list
203 * This list is created during user context creation and
204 * contains elements which describe sets (of 8) of empty
205 * RcvArray entries.
206 * 2. List of partially used groups - tid_used_list
207 * This list contains sets of RcvArray entries which are
208 * not completely used up. Another mapping request could
209 * use some of all of the remaining entries.
210 * 3. List of full groups - tid_full_list
211 * This is the list where sets that are completely used
212 * up go.
213 *
214 * An attempt to optimize the usage of RcvArray entries is
215 * made by finding all sets of physically contiguous pages in a
216 * user's buffer.
217 * These physically contiguous sets are further split into
218 * sizes supported by the receive engine of the HFI. The
219 * resulting sets of pages are stored in struct tid_pageset,
220 * which describes the sets as:
221 * * .count - number of pages in this set
222 * * .idx - starting index into struct page ** array
223 * of this set
224 *
225 * From this point on, the algorithm deals with the page sets
226 * described above. The number of pagesets is divided by the
227 * RcvArray group size to produce the number of full groups
228 * needed.
229 *
230 * Groups from the 3 lists are manipulated using the following
231 * rules:
232 * 1. For each set of 8 pagesets, a complete group from
233 * tid_group_list is taken, programmed, and moved to
234 * the tid_full_list list.
235 * 2. For all remaining pagesets:
236 * 2.1 If the tid_used_list is empty and the tid_group_list
237 * is empty, stop processing pageset and return only
238 * what has been programmed up to this point.
239 * 2.2 If the tid_used_list is empty and the tid_group_list
240 * is not empty, move a group from tid_group_list to
241 * tid_used_list.
242 * 2.3 For each group is tid_used_group, program as much as
243 * can fit into the group. If the group becomes fully
244 * used, move it to tid_full_list.
245 */
hfi1_user_exp_rcv_setup(struct hfi1_filedata * fd,struct hfi1_tid_info * tinfo)246 int hfi1_user_exp_rcv_setup(struct hfi1_filedata *fd,
247 struct hfi1_tid_info *tinfo)
248 {
249 int ret = 0, need_group = 0, pinned;
250 struct hfi1_ctxtdata *uctxt = fd->uctxt;
251 struct hfi1_devdata *dd = uctxt->dd;
252 unsigned int ngroups, pageset_count,
253 tididx = 0, mapped, mapped_pages = 0;
254 u32 *tidlist = NULL;
255 struct tid_user_buf *tidbuf;
256 unsigned long mmu_seq = 0;
257
258 if (!PAGE_ALIGNED(tinfo->vaddr))
259 return -EINVAL;
260 if (tinfo->length == 0)
261 return -EINVAL;
262
263 tidbuf = kzalloc(sizeof(*tidbuf), GFP_KERNEL);
264 if (!tidbuf)
265 return -ENOMEM;
266
267 mutex_init(&tidbuf->cover_mutex);
268 tidbuf->vaddr = tinfo->vaddr;
269 tidbuf->length = tinfo->length;
270 tidbuf->npages = num_user_pages(tidbuf->vaddr, tidbuf->length);
271 tidbuf->psets = kcalloc(uctxt->expected_count, sizeof(*tidbuf->psets),
272 GFP_KERNEL);
273 if (!tidbuf->psets) {
274 ret = -ENOMEM;
275 goto fail_release_mem;
276 }
277
278 if (fd->use_mn) {
279 ret = mmu_interval_notifier_insert(
280 &tidbuf->notifier, current->mm,
281 tidbuf->vaddr, tidbuf->npages * PAGE_SIZE,
282 &tid_cover_ops);
283 if (ret)
284 goto fail_release_mem;
285 mmu_seq = mmu_interval_read_begin(&tidbuf->notifier);
286 }
287
288 pinned = pin_rcv_pages(fd, tidbuf);
289 if (pinned <= 0) {
290 ret = (pinned < 0) ? pinned : -ENOSPC;
291 goto fail_unpin;
292 }
293
294 /* Find sets of physically contiguous pages */
295 tidbuf->n_psets = find_phys_blocks(tidbuf, pinned);
296
297 /* Reserve the number of expected tids to be used. */
298 spin_lock(&fd->tid_lock);
299 if (fd->tid_used + tidbuf->n_psets > fd->tid_limit)
300 pageset_count = fd->tid_limit - fd->tid_used;
301 else
302 pageset_count = tidbuf->n_psets;
303 fd->tid_used += pageset_count;
304 spin_unlock(&fd->tid_lock);
305
306 if (!pageset_count) {
307 ret = -ENOSPC;
308 goto fail_unreserve;
309 }
310
311 ngroups = pageset_count / dd->rcv_entries.group_size;
312 tidlist = kcalloc(pageset_count, sizeof(*tidlist), GFP_KERNEL);
313 if (!tidlist) {
314 ret = -ENOMEM;
315 goto fail_unreserve;
316 }
317
318 tididx = 0;
319
320 /*
321 * From this point on, we are going to be using shared (between master
322 * and subcontexts) context resources. We need to take the lock.
323 */
324 mutex_lock(&uctxt->exp_mutex);
325 /*
326 * The first step is to program the RcvArray entries which are complete
327 * groups.
328 */
329 while (ngroups && uctxt->tid_group_list.count) {
330 struct tid_group *grp =
331 tid_group_pop(&uctxt->tid_group_list);
332
333 ret = program_rcvarray(fd, tidbuf, grp,
334 dd->rcv_entries.group_size,
335 tidlist, &tididx, &mapped);
336 /*
337 * If there was a failure to program the RcvArray
338 * entries for the entire group, reset the grp fields
339 * and add the grp back to the free group list.
340 */
341 if (ret <= 0) {
342 tid_group_add_tail(grp, &uctxt->tid_group_list);
343 hfi1_cdbg(TID,
344 "Failed to program RcvArray group %d", ret);
345 goto unlock;
346 }
347
348 tid_group_add_tail(grp, &uctxt->tid_full_list);
349 ngroups--;
350 mapped_pages += mapped;
351 }
352
353 while (tididx < pageset_count) {
354 struct tid_group *grp, *ptr;
355 /*
356 * If we don't have any partially used tid groups, check
357 * if we have empty groups. If so, take one from there and
358 * put in the partially used list.
359 */
360 if (!uctxt->tid_used_list.count || need_group) {
361 if (!uctxt->tid_group_list.count)
362 goto unlock;
363
364 grp = tid_group_pop(&uctxt->tid_group_list);
365 tid_group_add_tail(grp, &uctxt->tid_used_list);
366 need_group = 0;
367 }
368 /*
369 * There is an optimization opportunity here - instead of
370 * fitting as many page sets as we can, check for a group
371 * later on in the list that could fit all of them.
372 */
373 list_for_each_entry_safe(grp, ptr, &uctxt->tid_used_list.list,
374 list) {
375 unsigned use = min_t(unsigned, pageset_count - tididx,
376 grp->size - grp->used);
377
378 ret = program_rcvarray(fd, tidbuf, grp,
379 use, tidlist,
380 &tididx, &mapped);
381 if (ret < 0) {
382 hfi1_cdbg(TID,
383 "Failed to program RcvArray entries %d",
384 ret);
385 goto unlock;
386 } else if (ret > 0) {
387 if (grp->used == grp->size)
388 tid_group_move(grp,
389 &uctxt->tid_used_list,
390 &uctxt->tid_full_list);
391 mapped_pages += mapped;
392 need_group = 0;
393 /* Check if we are done so we break out early */
394 if (tididx >= pageset_count)
395 break;
396 } else if (WARN_ON(ret == 0)) {
397 /*
398 * If ret is 0, we did not program any entries
399 * into this group, which can only happen if
400 * we've screwed up the accounting somewhere.
401 * Warn and try to continue.
402 */
403 need_group = 1;
404 }
405 }
406 }
407 unlock:
408 mutex_unlock(&uctxt->exp_mutex);
409 hfi1_cdbg(TID, "total mapped: tidpairs:%u pages:%u (%d)", tididx,
410 mapped_pages, ret);
411
412 /* fail if nothing was programmed, set error if none provided */
413 if (tididx == 0) {
414 if (ret >= 0)
415 ret = -ENOSPC;
416 goto fail_unreserve;
417 }
418
419 /* adjust reserved tid_used to actual count */
420 spin_lock(&fd->tid_lock);
421 fd->tid_used -= pageset_count - tididx;
422 spin_unlock(&fd->tid_lock);
423
424 /* unpin all pages not covered by a TID */
425 unpin_rcv_pages(fd, tidbuf, NULL, mapped_pages, pinned - mapped_pages,
426 false);
427
428 if (fd->use_mn) {
429 /* check for an invalidate during setup */
430 bool fail = false;
431
432 mutex_lock(&tidbuf->cover_mutex);
433 fail = mmu_interval_read_retry(&tidbuf->notifier, mmu_seq);
434 mutex_unlock(&tidbuf->cover_mutex);
435
436 if (fail) {
437 ret = -EBUSY;
438 goto fail_unprogram;
439 }
440 }
441
442 tinfo->tidcnt = tididx;
443 tinfo->length = mapped_pages * PAGE_SIZE;
444
445 if (copy_to_user(u64_to_user_ptr(tinfo->tidlist),
446 tidlist, sizeof(tidlist[0]) * tididx)) {
447 ret = -EFAULT;
448 goto fail_unprogram;
449 }
450
451 if (fd->use_mn)
452 mmu_interval_notifier_remove(&tidbuf->notifier);
453 kfree(tidbuf->pages);
454 kfree(tidbuf->psets);
455 kfree(tidbuf);
456 kfree(tidlist);
457 return 0;
458
459 fail_unprogram:
460 /* unprogram, unmap, and unpin all allocated TIDs */
461 tinfo->tidlist = (unsigned long)tidlist;
462 hfi1_user_exp_rcv_clear(fd, tinfo);
463 tinfo->tidlist = 0;
464 pinned = 0; /* nothing left to unpin */
465 pageset_count = 0; /* nothing left reserved */
466 fail_unreserve:
467 spin_lock(&fd->tid_lock);
468 fd->tid_used -= pageset_count;
469 spin_unlock(&fd->tid_lock);
470 fail_unpin:
471 if (fd->use_mn)
472 mmu_interval_notifier_remove(&tidbuf->notifier);
473 if (pinned > 0)
474 unpin_rcv_pages(fd, tidbuf, NULL, 0, pinned, false);
475 fail_release_mem:
476 kfree(tidbuf->pages);
477 kfree(tidbuf->psets);
478 kfree(tidbuf);
479 kfree(tidlist);
480 return ret;
481 }
482
hfi1_user_exp_rcv_clear(struct hfi1_filedata * fd,struct hfi1_tid_info * tinfo)483 int hfi1_user_exp_rcv_clear(struct hfi1_filedata *fd,
484 struct hfi1_tid_info *tinfo)
485 {
486 int ret = 0;
487 struct hfi1_ctxtdata *uctxt = fd->uctxt;
488 u32 *tidinfo;
489 unsigned tididx;
490
491 if (unlikely(tinfo->tidcnt > fd->tid_used))
492 return -EINVAL;
493
494 tidinfo = memdup_array_user(u64_to_user_ptr(tinfo->tidlist),
495 tinfo->tidcnt, sizeof(tidinfo[0]));
496 if (IS_ERR(tidinfo))
497 return PTR_ERR(tidinfo);
498
499 mutex_lock(&uctxt->exp_mutex);
500 for (tididx = 0; tididx < tinfo->tidcnt; tididx++) {
501 ret = unprogram_rcvarray(fd, tidinfo[tididx]);
502 if (ret) {
503 hfi1_cdbg(TID, "Failed to unprogram rcv array %d",
504 ret);
505 break;
506 }
507 }
508 spin_lock(&fd->tid_lock);
509 fd->tid_used -= tididx;
510 spin_unlock(&fd->tid_lock);
511 tinfo->tidcnt = tididx;
512 mutex_unlock(&uctxt->exp_mutex);
513
514 kfree(tidinfo);
515 return ret;
516 }
517
hfi1_user_exp_rcv_invalid(struct hfi1_filedata * fd,struct hfi1_tid_info * tinfo)518 int hfi1_user_exp_rcv_invalid(struct hfi1_filedata *fd,
519 struct hfi1_tid_info *tinfo)
520 {
521 struct hfi1_ctxtdata *uctxt = fd->uctxt;
522 unsigned long *ev = uctxt->dd->events +
523 (uctxt_offset(uctxt) + fd->subctxt);
524 u32 *array;
525 int ret = 0;
526
527 /*
528 * copy_to_user() can sleep, which will leave the invalid_lock
529 * locked and cause the MMU notifier to be blocked on the lock
530 * for a long time.
531 * Copy the data to a local buffer so we can release the lock.
532 */
533 array = kcalloc(uctxt->expected_count, sizeof(*array), GFP_KERNEL);
534 if (!array)
535 return -EFAULT;
536
537 spin_lock(&fd->invalid_lock);
538 if (fd->invalid_tid_idx) {
539 memcpy(array, fd->invalid_tids, sizeof(*array) *
540 fd->invalid_tid_idx);
541 memset(fd->invalid_tids, 0, sizeof(*fd->invalid_tids) *
542 fd->invalid_tid_idx);
543 tinfo->tidcnt = fd->invalid_tid_idx;
544 fd->invalid_tid_idx = 0;
545 /*
546 * Reset the user flag while still holding the lock.
547 * Otherwise, PSM can miss events.
548 */
549 clear_bit(_HFI1_EVENT_TID_MMU_NOTIFY_BIT, ev);
550 } else {
551 tinfo->tidcnt = 0;
552 }
553 spin_unlock(&fd->invalid_lock);
554
555 if (tinfo->tidcnt) {
556 if (copy_to_user((void __user *)tinfo->tidlist,
557 array, sizeof(*array) * tinfo->tidcnt))
558 ret = -EFAULT;
559 }
560 kfree(array);
561
562 return ret;
563 }
564
find_phys_blocks(struct tid_user_buf * tidbuf,unsigned int npages)565 static u32 find_phys_blocks(struct tid_user_buf *tidbuf, unsigned int npages)
566 {
567 unsigned pagecount, pageidx, setcount = 0, i;
568 unsigned long pfn, this_pfn;
569 struct page **pages = tidbuf->pages;
570 struct tid_pageset *list = tidbuf->psets;
571
572 if (!npages)
573 return 0;
574
575 /*
576 * Look for sets of physically contiguous pages in the user buffer.
577 * This will allow us to optimize Expected RcvArray entry usage by
578 * using the bigger supported sizes.
579 */
580 pfn = page_to_pfn(pages[0]);
581 for (pageidx = 0, pagecount = 1, i = 1; i <= npages; i++) {
582 this_pfn = i < npages ? page_to_pfn(pages[i]) : 0;
583
584 /*
585 * If the pfn's are not sequential, pages are not physically
586 * contiguous.
587 */
588 if (this_pfn != ++pfn) {
589 /*
590 * At this point we have to loop over the set of
591 * physically contiguous pages and break them down it
592 * sizes supported by the HW.
593 * There are two main constraints:
594 * 1. The max buffer size is MAX_EXPECTED_BUFFER.
595 * If the total set size is bigger than that
596 * program only a MAX_EXPECTED_BUFFER chunk.
597 * 2. The buffer size has to be a power of two. If
598 * it is not, round down to the closes power of
599 * 2 and program that size.
600 */
601 while (pagecount) {
602 int maxpages = pagecount;
603 u32 bufsize = pagecount * PAGE_SIZE;
604
605 if (bufsize > MAX_EXPECTED_BUFFER)
606 maxpages =
607 MAX_EXPECTED_BUFFER >>
608 PAGE_SHIFT;
609 else if (!is_power_of_2(bufsize))
610 maxpages =
611 rounddown_pow_of_two(bufsize) >>
612 PAGE_SHIFT;
613
614 list[setcount].idx = pageidx;
615 list[setcount].count = maxpages;
616 pagecount -= maxpages;
617 pageidx += maxpages;
618 setcount++;
619 }
620 pageidx = i;
621 pagecount = 1;
622 pfn = this_pfn;
623 } else {
624 pagecount++;
625 }
626 }
627 return setcount;
628 }
629
630 /**
631 * program_rcvarray() - program an RcvArray group with receive buffers
632 * @fd: filedata pointer
633 * @tbuf: pointer to struct tid_user_buf that has the user buffer starting
634 * virtual address, buffer length, page pointers, pagesets (array of
635 * struct tid_pageset holding information on physically contiguous
636 * chunks from the user buffer), and other fields.
637 * @grp: RcvArray group
638 * @count: number of struct tid_pageset's to program
639 * @tidlist: the array of u32 elements when the information about the
640 * programmed RcvArray entries is to be encoded.
641 * @tididx: starting offset into tidlist
642 * @pmapped: (output parameter) number of pages programmed into the RcvArray
643 * entries.
644 *
645 * This function will program up to 'count' number of RcvArray entries from the
646 * group 'grp'. To make best use of write-combining writes, the function will
647 * perform writes to the unused RcvArray entries which will be ignored by the
648 * HW. Each RcvArray entry will be programmed with a physically contiguous
649 * buffer chunk from the user's virtual buffer.
650 *
651 * Return:
652 * -EINVAL if the requested count is larger than the size of the group,
653 * -ENOMEM or -EFAULT on error from set_rcvarray_entry(), or
654 * number of RcvArray entries programmed.
655 */
program_rcvarray(struct hfi1_filedata * fd,struct tid_user_buf * tbuf,struct tid_group * grp,u16 count,u32 * tidlist,unsigned int * tididx,unsigned int * pmapped)656 static int program_rcvarray(struct hfi1_filedata *fd, struct tid_user_buf *tbuf,
657 struct tid_group *grp, u16 count,
658 u32 *tidlist, unsigned int *tididx,
659 unsigned int *pmapped)
660 {
661 struct hfi1_ctxtdata *uctxt = fd->uctxt;
662 struct hfi1_devdata *dd = uctxt->dd;
663 u16 idx;
664 unsigned int start = *tididx;
665 u32 tidinfo = 0, rcventry, useidx = 0;
666 int mapped = 0;
667
668 /* Count should never be larger than the group size */
669 if (count > grp->size)
670 return -EINVAL;
671
672 /* Find the first unused entry in the group */
673 for (idx = 0; idx < grp->size; idx++) {
674 if (!(grp->map & (1 << idx))) {
675 useidx = idx;
676 break;
677 }
678 rcv_array_wc_fill(dd, grp->base + idx);
679 }
680
681 idx = 0;
682 while (idx < count) {
683 u16 npages, pageidx, setidx = start + idx;
684 int ret = 0;
685
686 /*
687 * If this entry in the group is used, move to the next one.
688 * If we go past the end of the group, exit the loop.
689 */
690 if (useidx >= grp->size) {
691 break;
692 } else if (grp->map & (1 << useidx)) {
693 rcv_array_wc_fill(dd, grp->base + useidx);
694 useidx++;
695 continue;
696 }
697
698 rcventry = grp->base + useidx;
699 npages = tbuf->psets[setidx].count;
700 pageidx = tbuf->psets[setidx].idx;
701
702 ret = set_rcvarray_entry(fd, tbuf,
703 rcventry, grp, pageidx,
704 npages);
705 if (ret)
706 return ret;
707 mapped += npages;
708
709 tidinfo = create_tid(rcventry - uctxt->expected_base, npages);
710 tidlist[(*tididx)++] = tidinfo;
711 grp->used++;
712 grp->map |= 1 << useidx++;
713 idx++;
714 }
715
716 /* Fill the rest of the group with "blank" writes */
717 for (; useidx < grp->size; useidx++)
718 rcv_array_wc_fill(dd, grp->base + useidx);
719 *pmapped = mapped;
720 return idx;
721 }
722
set_rcvarray_entry(struct hfi1_filedata * fd,struct tid_user_buf * tbuf,u32 rcventry,struct tid_group * grp,u16 pageidx,unsigned int npages)723 static int set_rcvarray_entry(struct hfi1_filedata *fd,
724 struct tid_user_buf *tbuf,
725 u32 rcventry, struct tid_group *grp,
726 u16 pageidx, unsigned int npages)
727 {
728 int ret;
729 struct hfi1_ctxtdata *uctxt = fd->uctxt;
730 struct tid_rb_node *node;
731 struct hfi1_devdata *dd = uctxt->dd;
732 dma_addr_t phys;
733 struct page **pages = tbuf->pages + pageidx;
734
735 /*
736 * Allocate the node first so we can handle a potential
737 * failure before we've programmed anything.
738 */
739 node = kzalloc(struct_size(node, pages, npages), GFP_KERNEL);
740 if (!node)
741 return -ENOMEM;
742
743 phys = dma_map_single(&dd->pcidev->dev, __va(page_to_phys(pages[0])),
744 npages * PAGE_SIZE, DMA_FROM_DEVICE);
745 if (dma_mapping_error(&dd->pcidev->dev, phys)) {
746 dd_dev_err(dd, "Failed to DMA map Exp Rcv pages 0x%llx\n",
747 phys);
748 kfree(node);
749 return -EFAULT;
750 }
751
752 node->fdata = fd;
753 mutex_init(&node->invalidate_mutex);
754 node->phys = page_to_phys(pages[0]);
755 node->npages = npages;
756 node->rcventry = rcventry;
757 node->dma_addr = phys;
758 node->grp = grp;
759 node->freed = false;
760 memcpy(node->pages, pages, flex_array_size(node, pages, npages));
761
762 if (fd->use_mn) {
763 ret = mmu_interval_notifier_insert(
764 &node->notifier, current->mm,
765 tbuf->vaddr + (pageidx * PAGE_SIZE), npages * PAGE_SIZE,
766 &tid_mn_ops);
767 if (ret)
768 goto out_unmap;
769 }
770 fd->entry_to_rb[node->rcventry - uctxt->expected_base] = node;
771
772 hfi1_put_tid(dd, rcventry, PT_EXPECTED, phys, ilog2(npages) + 1);
773 trace_hfi1_exp_tid_reg(uctxt->ctxt, fd->subctxt, rcventry, npages,
774 node->notifier.interval_tree.start, node->phys,
775 phys);
776 return 0;
777
778 out_unmap:
779 hfi1_cdbg(TID, "Failed to insert RB node %u 0x%lx, 0x%lx %d",
780 node->rcventry, node->notifier.interval_tree.start,
781 node->phys, ret);
782 dma_unmap_single(&dd->pcidev->dev, phys, npages * PAGE_SIZE,
783 DMA_FROM_DEVICE);
784 kfree(node);
785 return -EFAULT;
786 }
787
unprogram_rcvarray(struct hfi1_filedata * fd,u32 tidinfo)788 static int unprogram_rcvarray(struct hfi1_filedata *fd, u32 tidinfo)
789 {
790 struct hfi1_ctxtdata *uctxt = fd->uctxt;
791 struct hfi1_devdata *dd = uctxt->dd;
792 struct tid_rb_node *node;
793 u32 tidctrl = EXP_TID_GET(tidinfo, CTRL);
794 u32 tididx = EXP_TID_GET(tidinfo, IDX) << 1, rcventry;
795
796 if (tidctrl == 0x3 || tidctrl == 0x0)
797 return -EINVAL;
798
799 rcventry = tididx + (tidctrl - 1);
800
801 if (rcventry >= uctxt->expected_count) {
802 dd_dev_err(dd, "Invalid RcvArray entry (%u) index for ctxt %u\n",
803 rcventry, uctxt->ctxt);
804 return -EINVAL;
805 }
806
807 node = fd->entry_to_rb[rcventry];
808 if (!node || node->rcventry != (uctxt->expected_base + rcventry))
809 return -EBADF;
810
811 if (fd->use_mn)
812 mmu_interval_notifier_remove(&node->notifier);
813 cacheless_tid_rb_remove(fd, node);
814
815 return 0;
816 }
817
__clear_tid_node(struct hfi1_filedata * fd,struct tid_rb_node * node)818 static void __clear_tid_node(struct hfi1_filedata *fd, struct tid_rb_node *node)
819 {
820 struct hfi1_ctxtdata *uctxt = fd->uctxt;
821 struct hfi1_devdata *dd = uctxt->dd;
822
823 mutex_lock(&node->invalidate_mutex);
824 if (node->freed)
825 goto done;
826 node->freed = true;
827
828 trace_hfi1_exp_tid_unreg(uctxt->ctxt, fd->subctxt, node->rcventry,
829 node->npages,
830 node->notifier.interval_tree.start, node->phys,
831 node->dma_addr);
832
833 /* Make sure device has seen the write before pages are unpinned */
834 hfi1_put_tid(dd, node->rcventry, PT_INVALID_FLUSH, 0, 0);
835
836 unpin_rcv_pages(fd, NULL, node, 0, node->npages, true);
837 done:
838 mutex_unlock(&node->invalidate_mutex);
839 }
840
clear_tid_node(struct hfi1_filedata * fd,struct tid_rb_node * node)841 static void clear_tid_node(struct hfi1_filedata *fd, struct tid_rb_node *node)
842 {
843 struct hfi1_ctxtdata *uctxt = fd->uctxt;
844
845 __clear_tid_node(fd, node);
846
847 node->grp->used--;
848 node->grp->map &= ~(1 << (node->rcventry - node->grp->base));
849
850 if (node->grp->used == node->grp->size - 1)
851 tid_group_move(node->grp, &uctxt->tid_full_list,
852 &uctxt->tid_used_list);
853 else if (!node->grp->used)
854 tid_group_move(node->grp, &uctxt->tid_used_list,
855 &uctxt->tid_group_list);
856 kfree(node);
857 }
858
859 /*
860 * As a simple helper for hfi1_user_exp_rcv_free, this function deals with
861 * clearing nodes in the non-cached case.
862 */
unlock_exp_tids(struct hfi1_ctxtdata * uctxt,struct exp_tid_set * set,struct hfi1_filedata * fd)863 static void unlock_exp_tids(struct hfi1_ctxtdata *uctxt,
864 struct exp_tid_set *set,
865 struct hfi1_filedata *fd)
866 {
867 struct tid_group *grp, *ptr;
868 int i;
869
870 list_for_each_entry_safe(grp, ptr, &set->list, list) {
871 list_del_init(&grp->list);
872
873 for (i = 0; i < grp->size; i++) {
874 if (grp->map & (1 << i)) {
875 u16 rcventry = grp->base + i;
876 struct tid_rb_node *node;
877
878 node = fd->entry_to_rb[rcventry -
879 uctxt->expected_base];
880 if (!node || node->rcventry != rcventry)
881 continue;
882
883 if (fd->use_mn)
884 mmu_interval_notifier_remove(
885 &node->notifier);
886 cacheless_tid_rb_remove(fd, node);
887 }
888 }
889 }
890 }
891
tid_rb_invalidate(struct mmu_interval_notifier * mni,const struct mmu_notifier_range * range,unsigned long cur_seq)892 static bool tid_rb_invalidate(struct mmu_interval_notifier *mni,
893 const struct mmu_notifier_range *range,
894 unsigned long cur_seq)
895 {
896 struct tid_rb_node *node =
897 container_of(mni, struct tid_rb_node, notifier);
898 struct hfi1_filedata *fdata = node->fdata;
899 struct hfi1_ctxtdata *uctxt = fdata->uctxt;
900
901 if (node->freed)
902 return true;
903
904 /* take action only if unmapping */
905 if (range->event != MMU_NOTIFY_UNMAP)
906 return true;
907
908 trace_hfi1_exp_tid_inval(uctxt->ctxt, fdata->subctxt,
909 node->notifier.interval_tree.start,
910 node->rcventry, node->npages, node->dma_addr);
911
912 /* clear the hardware rcvarray entry */
913 __clear_tid_node(fdata, node);
914
915 spin_lock(&fdata->invalid_lock);
916 if (fdata->invalid_tid_idx < uctxt->expected_count) {
917 fdata->invalid_tids[fdata->invalid_tid_idx] =
918 create_tid(node->rcventry - uctxt->expected_base,
919 node->npages);
920 if (!fdata->invalid_tid_idx) {
921 unsigned long *ev;
922
923 /*
924 * hfi1_set_uevent_bits() sets a user event flag
925 * for all processes. Because calling into the
926 * driver to process TID cache invalidations is
927 * expensive and TID cache invalidations are
928 * handled on a per-process basis, we can
929 * optimize this to set the flag only for the
930 * process in question.
931 */
932 ev = uctxt->dd->events +
933 (uctxt_offset(uctxt) + fdata->subctxt);
934 set_bit(_HFI1_EVENT_TID_MMU_NOTIFY_BIT, ev);
935 }
936 fdata->invalid_tid_idx++;
937 }
938 spin_unlock(&fdata->invalid_lock);
939 return true;
940 }
941
tid_cover_invalidate(struct mmu_interval_notifier * mni,const struct mmu_notifier_range * range,unsigned long cur_seq)942 static bool tid_cover_invalidate(struct mmu_interval_notifier *mni,
943 const struct mmu_notifier_range *range,
944 unsigned long cur_seq)
945 {
946 struct tid_user_buf *tidbuf =
947 container_of(mni, struct tid_user_buf, notifier);
948
949 /* take action only if unmapping */
950 if (range->event == MMU_NOTIFY_UNMAP) {
951 mutex_lock(&tidbuf->cover_mutex);
952 mmu_interval_set_seq(mni, cur_seq);
953 mutex_unlock(&tidbuf->cover_mutex);
954 }
955
956 return true;
957 }
958
cacheless_tid_rb_remove(struct hfi1_filedata * fdata,struct tid_rb_node * tnode)959 static void cacheless_tid_rb_remove(struct hfi1_filedata *fdata,
960 struct tid_rb_node *tnode)
961 {
962 u32 base = fdata->uctxt->expected_base;
963
964 fdata->entry_to_rb[tnode->rcventry - base] = NULL;
965 clear_tid_node(fdata, tnode);
966 }
967