1 /*
2 * Copyright (c) 2005 Topspin Communications. All rights reserved.
3 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
4 * Copyright (c) 2013 Cisco Systems. All rights reserved.
5 *
6 * This software is available to you under a choice of one of two
7 * licenses. You may choose to be licensed under the terms of the GNU
8 * General Public License (GPL) Version 2, available from the file
9 * COPYING in the main directory of this source tree, or the
10 * BSD license below:
11 *
12 * Redistribution and use in source and binary forms, with or
13 * without modification, are permitted provided that the following
14 * conditions are met:
15 *
16 * - Redistributions of source code must retain the above
17 * copyright notice, this list of conditions and the following
18 * disclaimer.
19 *
20 * - Redistributions in binary form must reproduce the above
21 * copyright notice, this list of conditions and the following
22 * disclaimer in the documentation and/or other materials
23 * provided with the distribution.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32 * SOFTWARE.
33 */
34
35 #include <linux/mm.h>
36 #include <linux/dma-mapping.h>
37 #include <linux/sched/signal.h>
38 #include <linux/sched/mm.h>
39 #include <linux/hugetlb.h>
40 #include <linux/iommu.h>
41 #include <linux/workqueue.h>
42 #include <linux/list.h>
43 #include <rdma/ib_verbs.h>
44
45 #include "usnic_log.h"
46 #include "usnic_uiom.h"
47 #include "usnic_uiom_interval_tree.h"
48
49 #define USNIC_UIOM_PAGE_CHUNK \
50 ((PAGE_SIZE - offsetof(struct usnic_uiom_chunk, page_list)) /\
51 ((void *) &((struct usnic_uiom_chunk *) 0)->page_list[1] - \
52 (void *) &((struct usnic_uiom_chunk *) 0)->page_list[0]))
53
usnic_uiom_dma_fault(struct iommu_domain * domain,struct device * dev,unsigned long iova,int flags,void * token)54 static int usnic_uiom_dma_fault(struct iommu_domain *domain,
55 struct device *dev,
56 unsigned long iova, int flags,
57 void *token)
58 {
59 usnic_err("Device %s iommu fault domain 0x%pK va 0x%lx flags 0x%x\n",
60 dev_name(dev),
61 domain, iova, flags);
62 return -ENOSYS;
63 }
64
usnic_uiom_put_pages(struct list_head * chunk_list,int dirty)65 static void usnic_uiom_put_pages(struct list_head *chunk_list, int dirty)
66 {
67 struct usnic_uiom_chunk *chunk, *tmp;
68 struct page *page;
69 struct scatterlist *sg;
70 int i;
71 dma_addr_t pa;
72
73 list_for_each_entry_safe(chunk, tmp, chunk_list, list) {
74 for_each_sg(chunk->page_list, sg, chunk->nents, i) {
75 page = sg_page(sg);
76 pa = sg_phys(sg);
77 unpin_user_pages_dirty_lock(&page, 1, dirty);
78 usnic_dbg("pa: %pa\n", &pa);
79 }
80 kfree(chunk);
81 }
82 }
83
usnic_uiom_get_pages(unsigned long addr,size_t size,int writable,int dmasync,struct usnic_uiom_reg * uiomr)84 static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
85 int dmasync, struct usnic_uiom_reg *uiomr)
86 {
87 struct list_head *chunk_list = &uiomr->chunk_list;
88 unsigned int gup_flags = FOLL_LONGTERM;
89 struct page **page_list;
90 struct scatterlist *sg;
91 struct usnic_uiom_chunk *chunk;
92 unsigned long locked;
93 unsigned long lock_limit;
94 unsigned long cur_base;
95 unsigned long npages;
96 int ret;
97 int off;
98 int i;
99 dma_addr_t pa;
100 struct mm_struct *mm;
101
102 /*
103 * If the combination of the addr and size requested for this memory
104 * region causes an integer overflow, return error.
105 */
106 if (((addr + size) < addr) || PAGE_ALIGN(addr + size) < (addr + size))
107 return -EINVAL;
108
109 if (!size)
110 return -EINVAL;
111
112 if (!can_do_mlock())
113 return -EPERM;
114
115 INIT_LIST_HEAD(chunk_list);
116
117 page_list = (struct page **) __get_free_page(GFP_KERNEL);
118 if (!page_list)
119 return -ENOMEM;
120
121 npages = PAGE_ALIGN(size + (addr & ~PAGE_MASK)) >> PAGE_SHIFT;
122
123 uiomr->owning_mm = mm = current->mm;
124 mmap_read_lock(mm);
125
126 locked = atomic64_add_return(npages, ¤t->mm->pinned_vm);
127 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
128
129 if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
130 ret = -ENOMEM;
131 goto out;
132 }
133
134 if (writable)
135 gup_flags |= FOLL_WRITE;
136 cur_base = addr & PAGE_MASK;
137 ret = 0;
138
139 while (npages) {
140 ret = pin_user_pages(cur_base,
141 min_t(unsigned long, npages,
142 PAGE_SIZE / sizeof(struct page *)),
143 gup_flags, page_list);
144
145 if (ret < 0)
146 goto out;
147
148 npages -= ret;
149 off = 0;
150
151 while (ret) {
152 chunk = kmalloc(struct_size(chunk, page_list,
153 min_t(int, ret, USNIC_UIOM_PAGE_CHUNK)),
154 GFP_KERNEL);
155 if (!chunk) {
156 ret = -ENOMEM;
157 goto out;
158 }
159
160 chunk->nents = min_t(int, ret, USNIC_UIOM_PAGE_CHUNK);
161 sg_init_table(chunk->page_list, chunk->nents);
162 for_each_sg(chunk->page_list, sg, chunk->nents, i) {
163 sg_set_page(sg, page_list[i + off],
164 PAGE_SIZE, 0);
165 pa = sg_phys(sg);
166 usnic_dbg("va: 0x%lx pa: %pa\n",
167 cur_base + i*PAGE_SIZE, &pa);
168 }
169 cur_base += chunk->nents * PAGE_SIZE;
170 ret -= chunk->nents;
171 off += chunk->nents;
172 list_add_tail(&chunk->list, chunk_list);
173 }
174
175 ret = 0;
176 }
177
178 out:
179 if (ret < 0) {
180 usnic_uiom_put_pages(chunk_list, 0);
181 atomic64_sub(npages, ¤t->mm->pinned_vm);
182 } else
183 mmgrab(uiomr->owning_mm);
184
185 mmap_read_unlock(mm);
186 free_page((unsigned long) page_list);
187 return ret;
188 }
189
usnic_uiom_unmap_sorted_intervals(struct list_head * intervals,struct usnic_uiom_pd * pd)190 static void usnic_uiom_unmap_sorted_intervals(struct list_head *intervals,
191 struct usnic_uiom_pd *pd)
192 {
193 struct usnic_uiom_interval_node *interval, *tmp;
194 long unsigned va, size;
195
196 list_for_each_entry_safe(interval, tmp, intervals, link) {
197 va = interval->start << PAGE_SHIFT;
198 size = ((interval->last - interval->start) + 1) << PAGE_SHIFT;
199 while (size > 0) {
200 /* Workaround for RH 970401 */
201 usnic_dbg("va 0x%lx size 0x%lx", va, PAGE_SIZE);
202 iommu_unmap(pd->domain, va, PAGE_SIZE);
203 va += PAGE_SIZE;
204 size -= PAGE_SIZE;
205 }
206 }
207 }
208
__usnic_uiom_reg_release(struct usnic_uiom_pd * pd,struct usnic_uiom_reg * uiomr,int dirty)209 static void __usnic_uiom_reg_release(struct usnic_uiom_pd *pd,
210 struct usnic_uiom_reg *uiomr,
211 int dirty)
212 {
213 int npages;
214 unsigned long vpn_start, vpn_last;
215 struct usnic_uiom_interval_node *interval, *tmp;
216 int writable = 0;
217 LIST_HEAD(rm_intervals);
218
219 npages = PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT;
220 vpn_start = (uiomr->va & PAGE_MASK) >> PAGE_SHIFT;
221 vpn_last = vpn_start + npages - 1;
222
223 spin_lock(&pd->lock);
224 usnic_uiom_remove_interval(&pd->root, vpn_start,
225 vpn_last, &rm_intervals);
226 usnic_uiom_unmap_sorted_intervals(&rm_intervals, pd);
227
228 list_for_each_entry_safe(interval, tmp, &rm_intervals, link) {
229 if (interval->flags & IOMMU_WRITE)
230 writable = 1;
231 list_del(&interval->link);
232 kfree(interval);
233 }
234
235 usnic_uiom_put_pages(&uiomr->chunk_list, dirty & writable);
236 spin_unlock(&pd->lock);
237 }
238
usnic_uiom_map_sorted_intervals(struct list_head * intervals,struct usnic_uiom_reg * uiomr)239 static int usnic_uiom_map_sorted_intervals(struct list_head *intervals,
240 struct usnic_uiom_reg *uiomr)
241 {
242 int i, err;
243 size_t size;
244 struct usnic_uiom_chunk *chunk;
245 struct usnic_uiom_interval_node *interval_node;
246 dma_addr_t pa;
247 dma_addr_t pa_start = 0;
248 dma_addr_t pa_end = 0;
249 long int va_start = -EINVAL;
250 struct usnic_uiom_pd *pd = uiomr->pd;
251 long int va = uiomr->va & PAGE_MASK;
252 int flags = IOMMU_READ | IOMMU_CACHE;
253
254 flags |= (uiomr->writable) ? IOMMU_WRITE : 0;
255 chunk = list_first_entry(&uiomr->chunk_list, struct usnic_uiom_chunk,
256 list);
257 list_for_each_entry(interval_node, intervals, link) {
258 iter_chunk:
259 for (i = 0; i < chunk->nents; i++, va += PAGE_SIZE) {
260 pa = sg_phys(&chunk->page_list[i]);
261 if ((va >> PAGE_SHIFT) < interval_node->start)
262 continue;
263
264 if ((va >> PAGE_SHIFT) == interval_node->start) {
265 /* First page of the interval */
266 va_start = va;
267 pa_start = pa;
268 pa_end = pa;
269 }
270
271 WARN_ON(va_start == -EINVAL);
272
273 if ((pa_end + PAGE_SIZE != pa) &&
274 (pa != pa_start)) {
275 /* PAs are not contiguous */
276 size = pa_end - pa_start + PAGE_SIZE;
277 usnic_dbg("va 0x%lx pa %pa size 0x%zx flags 0x%x",
278 va_start, &pa_start, size, flags);
279 err = iommu_map(pd->domain, va_start, pa_start,
280 size, flags, GFP_ATOMIC);
281 if (err) {
282 usnic_err("Failed to map va 0x%lx pa %pa size 0x%zx with err %d\n",
283 va_start, &pa_start, size, err);
284 goto err_out;
285 }
286 va_start = va;
287 pa_start = pa;
288 pa_end = pa;
289 }
290
291 if ((va >> PAGE_SHIFT) == interval_node->last) {
292 /* Last page of the interval */
293 size = pa - pa_start + PAGE_SIZE;
294 usnic_dbg("va 0x%lx pa %pa size 0x%zx flags 0x%x\n",
295 va_start, &pa_start, size, flags);
296 err = iommu_map(pd->domain, va_start, pa_start,
297 size, flags, GFP_ATOMIC);
298 if (err) {
299 usnic_err("Failed to map va 0x%lx pa %pa size 0x%zx with err %d\n",
300 va_start, &pa_start, size, err);
301 goto err_out;
302 }
303 break;
304 }
305
306 if (pa != pa_start)
307 pa_end += PAGE_SIZE;
308 }
309
310 if (i == chunk->nents) {
311 /*
312 * Hit last entry of the chunk,
313 * hence advance to next chunk
314 */
315 chunk = list_first_entry(&chunk->list,
316 struct usnic_uiom_chunk,
317 list);
318 goto iter_chunk;
319 }
320 }
321
322 return 0;
323
324 err_out:
325 usnic_uiom_unmap_sorted_intervals(intervals, pd);
326 return err;
327 }
328
usnic_uiom_reg_get(struct usnic_uiom_pd * pd,unsigned long addr,size_t size,int writable,int dmasync)329 struct usnic_uiom_reg *usnic_uiom_reg_get(struct usnic_uiom_pd *pd,
330 unsigned long addr, size_t size,
331 int writable, int dmasync)
332 {
333 struct usnic_uiom_reg *uiomr;
334 unsigned long va_base, vpn_start, vpn_last;
335 unsigned long npages;
336 int offset, err;
337 LIST_HEAD(sorted_diff_intervals);
338
339 /*
340 * Intel IOMMU map throws an error if a translation entry is
341 * changed from read to write. This module may not unmap
342 * and then remap the entry after fixing the permission
343 * b/c this open up a small windows where hw DMA may page fault
344 * Hence, make all entries to be writable.
345 */
346 writable = 1;
347
348 va_base = addr & PAGE_MASK;
349 offset = addr & ~PAGE_MASK;
350 npages = PAGE_ALIGN(size + offset) >> PAGE_SHIFT;
351 vpn_start = (addr & PAGE_MASK) >> PAGE_SHIFT;
352 vpn_last = vpn_start + npages - 1;
353
354 uiomr = kmalloc(sizeof(*uiomr), GFP_KERNEL);
355 if (!uiomr)
356 return ERR_PTR(-ENOMEM);
357
358 uiomr->va = va_base;
359 uiomr->offset = offset;
360 uiomr->length = size;
361 uiomr->writable = writable;
362 uiomr->pd = pd;
363
364 err = usnic_uiom_get_pages(addr, size, writable, dmasync,
365 uiomr);
366 if (err) {
367 usnic_err("Failed get_pages vpn [0x%lx,0x%lx] err %d\n",
368 vpn_start, vpn_last, err);
369 goto out_free_uiomr;
370 }
371
372 spin_lock(&pd->lock);
373 err = usnic_uiom_get_intervals_diff(vpn_start, vpn_last,
374 (writable) ? IOMMU_WRITE : 0,
375 IOMMU_WRITE,
376 &pd->root,
377 &sorted_diff_intervals);
378 if (err) {
379 usnic_err("Failed disjoint interval vpn [0x%lx,0x%lx] err %d\n",
380 vpn_start, vpn_last, err);
381 goto out_put_pages;
382 }
383
384 err = usnic_uiom_map_sorted_intervals(&sorted_diff_intervals, uiomr);
385 if (err) {
386 usnic_err("Failed map interval vpn [0x%lx,0x%lx] err %d\n",
387 vpn_start, vpn_last, err);
388 goto out_put_intervals;
389
390 }
391
392 err = usnic_uiom_insert_interval(&pd->root, vpn_start, vpn_last,
393 (writable) ? IOMMU_WRITE : 0);
394 if (err) {
395 usnic_err("Failed insert interval vpn [0x%lx,0x%lx] err %d\n",
396 vpn_start, vpn_last, err);
397 goto out_unmap_intervals;
398 }
399
400 usnic_uiom_put_interval_set(&sorted_diff_intervals);
401 spin_unlock(&pd->lock);
402
403 return uiomr;
404
405 out_unmap_intervals:
406 usnic_uiom_unmap_sorted_intervals(&sorted_diff_intervals, pd);
407 out_put_intervals:
408 usnic_uiom_put_interval_set(&sorted_diff_intervals);
409 out_put_pages:
410 usnic_uiom_put_pages(&uiomr->chunk_list, 0);
411 spin_unlock(&pd->lock);
412 mmdrop(uiomr->owning_mm);
413 out_free_uiomr:
414 kfree(uiomr);
415 return ERR_PTR(err);
416 }
417
__usnic_uiom_release_tail(struct usnic_uiom_reg * uiomr)418 static void __usnic_uiom_release_tail(struct usnic_uiom_reg *uiomr)
419 {
420 mmdrop(uiomr->owning_mm);
421 kfree(uiomr);
422 }
423
usnic_uiom_num_pages(struct usnic_uiom_reg * uiomr)424 static inline size_t usnic_uiom_num_pages(struct usnic_uiom_reg *uiomr)
425 {
426 return PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT;
427 }
428
usnic_uiom_reg_release(struct usnic_uiom_reg * uiomr)429 void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr)
430 {
431 __usnic_uiom_reg_release(uiomr->pd, uiomr, 1);
432
433 atomic64_sub(usnic_uiom_num_pages(uiomr), &uiomr->owning_mm->pinned_vm);
434 __usnic_uiom_release_tail(uiomr);
435 }
436
usnic_uiom_alloc_pd(struct device * dev)437 struct usnic_uiom_pd *usnic_uiom_alloc_pd(struct device *dev)
438 {
439 struct usnic_uiom_pd *pd;
440 void *domain;
441
442 pd = kzalloc(sizeof(*pd), GFP_KERNEL);
443 if (!pd)
444 return ERR_PTR(-ENOMEM);
445
446 pd->domain = domain = iommu_domain_alloc(dev->bus);
447 if (!domain) {
448 usnic_err("Failed to allocate IOMMU domain");
449 kfree(pd);
450 return ERR_PTR(-ENOMEM);
451 }
452
453 iommu_set_fault_handler(pd->domain, usnic_uiom_dma_fault, NULL);
454
455 spin_lock_init(&pd->lock);
456 INIT_LIST_HEAD(&pd->devs);
457
458 return pd;
459 }
460
usnic_uiom_dealloc_pd(struct usnic_uiom_pd * pd)461 void usnic_uiom_dealloc_pd(struct usnic_uiom_pd *pd)
462 {
463 iommu_domain_free(pd->domain);
464 kfree(pd);
465 }
466
usnic_uiom_attach_dev_to_pd(struct usnic_uiom_pd * pd,struct device * dev)467 int usnic_uiom_attach_dev_to_pd(struct usnic_uiom_pd *pd, struct device *dev)
468 {
469 struct usnic_uiom_dev *uiom_dev;
470 int err;
471
472 uiom_dev = kzalloc(sizeof(*uiom_dev), GFP_ATOMIC);
473 if (!uiom_dev)
474 return -ENOMEM;
475 uiom_dev->dev = dev;
476
477 err = iommu_attach_device(pd->domain, dev);
478 if (err)
479 goto out_free_dev;
480
481 if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY)) {
482 usnic_err("IOMMU of %s does not support cache coherency\n",
483 dev_name(dev));
484 err = -EINVAL;
485 goto out_detach_device;
486 }
487
488 spin_lock(&pd->lock);
489 list_add_tail(&uiom_dev->link, &pd->devs);
490 pd->dev_cnt++;
491 spin_unlock(&pd->lock);
492
493 return 0;
494
495 out_detach_device:
496 iommu_detach_device(pd->domain, dev);
497 out_free_dev:
498 kfree(uiom_dev);
499 return err;
500 }
501
usnic_uiom_detach_dev_from_pd(struct usnic_uiom_pd * pd,struct device * dev)502 void usnic_uiom_detach_dev_from_pd(struct usnic_uiom_pd *pd, struct device *dev)
503 {
504 struct usnic_uiom_dev *uiom_dev;
505 int found = 0;
506
507 spin_lock(&pd->lock);
508 list_for_each_entry(uiom_dev, &pd->devs, link) {
509 if (uiom_dev->dev == dev) {
510 found = 1;
511 break;
512 }
513 }
514
515 if (!found) {
516 usnic_err("Unable to free dev %s - not found\n",
517 dev_name(dev));
518 spin_unlock(&pd->lock);
519 return;
520 }
521
522 list_del(&uiom_dev->link);
523 pd->dev_cnt--;
524 spin_unlock(&pd->lock);
525
526 return iommu_detach_device(pd->domain, dev);
527 }
528
usnic_uiom_get_dev_list(struct usnic_uiom_pd * pd)529 struct device **usnic_uiom_get_dev_list(struct usnic_uiom_pd *pd)
530 {
531 struct usnic_uiom_dev *uiom_dev;
532 struct device **devs;
533 int i = 0;
534
535 spin_lock(&pd->lock);
536 devs = kcalloc(pd->dev_cnt + 1, sizeof(*devs), GFP_ATOMIC);
537 if (!devs) {
538 devs = ERR_PTR(-ENOMEM);
539 goto out;
540 }
541
542 list_for_each_entry(uiom_dev, &pd->devs, link) {
543 devs[i++] = uiom_dev->dev;
544 }
545 out:
546 spin_unlock(&pd->lock);
547 return devs;
548 }
549
usnic_uiom_free_dev_list(struct device ** devs)550 void usnic_uiom_free_dev_list(struct device **devs)
551 {
552 kfree(devs);
553 }
554