1 /*
2 * Copyright (c) 2005 Topspin Communications. All rights reserved.
3 * Copyright (c) 2005 Cisco Systems. All rights reserved.
4 * Copyright (c) 2005 Mellanox Technologies. 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 * OpenIB.org 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.h>
38 #ifdef __linux__
39 #include <linux/hugetlb.h>
40 #endif
41 #include <linux/dma-attrs.h>
42
43 #include <sys/priv.h>
44 #include <sys/resource.h>
45 #include <sys/resourcevar.h>
46
47 #include <vm/vm.h>
48 #include <vm/vm_map.h>
49 #include <vm/vm_object.h>
50 #include <vm/vm_pageout.h>
51
52 #include "uverbs.h"
53
54 static int allow_weak_ordering;
55 module_param(allow_weak_ordering, bool, 0444);
56 MODULE_PARM_DESC(allow_weak_ordering, "Allow weak ordering for data registered memory");
57
58 #define IB_UMEM_MAX_PAGE_CHUNK \
59 ((PAGE_SIZE - offsetof(struct ib_umem_chunk, page_list)) / \
60 ((void *) &((struct ib_umem_chunk *) 0)->page_list[1] - \
61 (void *) &((struct ib_umem_chunk *) 0)->page_list[0]))
62
63 #ifdef __ia64__
64 extern int dma_map_sg_hp_wa;
65
dma_map_sg_ia64(struct ib_device * ibdev,struct scatterlist * sg,int nents,enum dma_data_direction dir)66 static int dma_map_sg_ia64(struct ib_device *ibdev,
67 struct scatterlist *sg,
68 int nents,
69 enum dma_data_direction dir)
70 {
71 int i, rc, j, lents = 0;
72 struct device *dev;
73
74 if (!dma_map_sg_hp_wa)
75 return ib_dma_map_sg(ibdev, sg, nents, dir);
76
77 dev = ibdev->dma_device;
78 for (i = 0; i < nents; ++i) {
79 rc = dma_map_sg(dev, sg + i, 1, dir);
80 if (rc <= 0) {
81 for (j = 0; j < i; ++j)
82 dma_unmap_sg(dev, sg + j, 1, dir);
83
84 return 0;
85 }
86 lents += rc;
87 }
88
89 return lents;
90 }
91
dma_unmap_sg_ia64(struct ib_device * ibdev,struct scatterlist * sg,int nents,enum dma_data_direction dir)92 static void dma_unmap_sg_ia64(struct ib_device *ibdev,
93 struct scatterlist *sg,
94 int nents,
95 enum dma_data_direction dir)
96 {
97 int i;
98 struct device *dev;
99
100 if (!dma_map_sg_hp_wa)
101 return ib_dma_unmap_sg(ibdev, sg, nents, dir);
102
103 dev = ibdev->dma_device;
104 for (i = 0; i < nents; ++i)
105 dma_unmap_sg(dev, sg + i, 1, dir);
106 }
107
108 #define ib_dma_map_sg(dev, sg, nents, dir) dma_map_sg_ia64(dev, sg, nents, dir)
109 #define ib_dma_unmap_sg(dev, sg, nents, dir) dma_unmap_sg_ia64(dev, sg, nents, dir)
110
111 #endif
112
__ib_umem_release(struct ib_device * dev,struct ib_umem * umem,int dirty)113 static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int dirty)
114 {
115 #ifdef __linux__
116 struct ib_umem_chunk *chunk, *tmp;
117 int i;
118
119 list_for_each_entry_safe(chunk, tmp, &umem->chunk_list, list) {
120 ib_dma_unmap_sg_attrs(dev, chunk->page_list,
121 chunk->nents, DMA_BIDIRECTIONAL, &chunk->attrs);
122 for (i = 0; i < chunk->nents; ++i) {
123 struct page *page = sg_page(&chunk->page_list[i]);
124 if (umem->writable && dirty)
125 set_page_dirty_lock(page);
126 put_page(page);
127 }
128 kfree(chunk);
129 }
130 #else
131 struct ib_umem_chunk *chunk, *tmp;
132 vm_object_t object;
133 int i;
134
135 object = NULL;
136 list_for_each_entry_safe(chunk, tmp, &umem->chunk_list, list) {
137 ib_dma_unmap_sg_attrs(dev, chunk->page_list,
138 chunk->nents, DMA_BIDIRECTIONAL, &chunk->attrs);
139 for (i = 0; i < chunk->nents; ++i) {
140 struct page *page = sg_page(&chunk->page_list[i]);
141 if (umem->writable && dirty) {
142 if (object && object != page->object)
143 VM_OBJECT_UNLOCK(object);
144 if (object != page->object) {
145 object = page->object;
146 VM_OBJECT_LOCK(object);
147 }
148 vm_page_dirty(page);
149 }
150 }
151 kfree(chunk);
152 }
153 if (object)
154 VM_OBJECT_UNLOCK(object);
155
156 #endif
157 }
158
159 /**
160 * ib_umem_get - Pin and DMA map userspace memory.
161 * @context: userspace context to pin memory for
162 * @addr: userspace virtual address to start at
163 * @size: length of region to pin
164 * @access: IB_ACCESS_xxx flags for memory being pinned
165 * @dmasync: flush in-flight DMA when the memory region is written
166 */
ib_umem_get(struct ib_ucontext * context,unsigned long addr,size_t size,int access,int dmasync)167 struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
168 size_t size, int access, int dmasync)
169 {
170 #ifdef __linux__
171 struct ib_umem *umem;
172 struct page **page_list;
173 struct vm_area_struct **vma_list;
174 struct ib_umem_chunk *chunk;
175 unsigned long locked;
176 unsigned long lock_limit;
177 unsigned long cur_base;
178 unsigned long npages;
179 int ret;
180 int off;
181 int i;
182 DEFINE_DMA_ATTRS(attrs);
183
184 if (dmasync)
185 dma_set_attr(DMA_ATTR_WRITE_BARRIER, &attrs);
186 else if (allow_weak_ordering)
187 dma_set_attr(DMA_ATTR_WEAK_ORDERING, &attrs);
188
189 if (!can_do_mlock())
190 return ERR_PTR(-EPERM);
191
192 umem = kmalloc(sizeof *umem, GFP_KERNEL);
193 if (!umem)
194 return ERR_PTR(-ENOMEM);
195
196 umem->context = context;
197 umem->length = size;
198 umem->offset = addr & ~PAGE_MASK;
199 umem->page_size = PAGE_SIZE;
200 /*
201 * We ask for writable memory if any access flags other than
202 * "remote read" are set. "Local write" and "remote write"
203 * obviously require write access. "Remote atomic" can do
204 * things like fetch and add, which will modify memory, and
205 * "MW bind" can change permissions by binding a window.
206 */
207 umem->writable = !!(access & ~IB_ACCESS_REMOTE_READ);
208
209 /* We assume the memory is from hugetlb until proved otherwise */
210 umem->hugetlb = 1;
211
212 INIT_LIST_HEAD(&umem->chunk_list);
213
214 page_list = (struct page **) __get_free_page(GFP_KERNEL);
215 if (!page_list) {
216 kfree(umem);
217 return ERR_PTR(-ENOMEM);
218 }
219
220 /*
221 * if we can't alloc the vma_list, it's not so bad;
222 * just assume the memory is not hugetlb memory
223 */
224 vma_list = (struct vm_area_struct **) __get_free_page(GFP_KERNEL);
225 if (!vma_list)
226 umem->hugetlb = 0;
227
228 npages = PAGE_ALIGN(size + umem->offset) >> PAGE_SHIFT;
229
230 down_write(¤t->mm->mmap_sem);
231
232 locked = npages + current->mm->locked_vm;
233 lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
234
235 if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
236 ret = -ENOMEM;
237 goto out;
238 }
239
240 cur_base = addr & PAGE_MASK;
241
242 ret = 0;
243
244 while (npages) {
245 ret = get_user_pages(current, current->mm, cur_base,
246 min_t(unsigned long, npages,
247 PAGE_SIZE / sizeof (struct page *)),
248 1, !umem->writable, page_list, vma_list);
249
250 if (ret < 0)
251 goto out;
252
253 cur_base += ret * PAGE_SIZE;
254 npages -= ret;
255
256 off = 0;
257
258 while (ret) {
259 chunk = kmalloc(sizeof *chunk + sizeof (struct scatterlist) *
260 min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK),
261 GFP_KERNEL);
262 if (!chunk) {
263 ret = -ENOMEM;
264 goto out;
265 }
266
267 chunk->attrs = attrs;
268 chunk->nents = min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK);
269 sg_init_table(chunk->page_list, chunk->nents);
270 for (i = 0; i < chunk->nents; ++i) {
271 if (vma_list &&
272 !is_vm_hugetlb_page(vma_list[i + off]))
273 umem->hugetlb = 0;
274 sg_set_page(&chunk->page_list[i], page_list[i + off], PAGE_SIZE, 0);
275 }
276
277 chunk->nmap = ib_dma_map_sg_attrs(context->device,
278 &chunk->page_list[0],
279 chunk->nents,
280 DMA_BIDIRECTIONAL,
281 &attrs);
282 if (chunk->nmap <= 0) {
283 for (i = 0; i < chunk->nents; ++i)
284 put_page(sg_page(&chunk->page_list[i]));
285 kfree(chunk);
286
287 ret = -ENOMEM;
288 goto out;
289 }
290
291 ret -= chunk->nents;
292 off += chunk->nents;
293 list_add_tail(&chunk->list, &umem->chunk_list);
294 }
295
296 ret = 0;
297 }
298
299 out:
300 if (ret < 0) {
301 __ib_umem_release(context->device, umem, 0);
302 kfree(umem);
303 } else
304 current->mm->locked_vm = locked;
305
306 up_write(¤t->mm->mmap_sem);
307 if (vma_list)
308 free_page((unsigned long) vma_list);
309 free_page((unsigned long) page_list);
310
311 return ret < 0 ? ERR_PTR(ret) : umem;
312 #else
313 struct ib_umem *umem;
314 struct ib_umem_chunk *chunk;
315 struct proc *proc;
316 pmap_t pmap;
317 vm_offset_t end, last, start;
318 vm_size_t npages;
319 int error;
320 int ents;
321 int ret;
322 int i;
323 DEFINE_DMA_ATTRS(attrs);
324
325 error = priv_check(curthread, PRIV_VM_MLOCK);
326 if (error)
327 return ERR_PTR(-error);
328
329 last = addr + size;
330 start = addr & PAGE_MASK; /* Use the linux PAGE_MASK definition. */
331 end = roundup2(last, PAGE_SIZE); /* Use PAGE_MASK safe operation. */
332 if (last < addr || end < addr)
333 return ERR_PTR(-EINVAL);
334 npages = atop(end - start);
335 if (npages > vm_page_max_wired)
336 return ERR_PTR(-ENOMEM);
337 umem = kzalloc(sizeof *umem, GFP_KERNEL);
338 if (!umem)
339 return ERR_PTR(-ENOMEM);
340 proc = curthread->td_proc;
341 PROC_LOCK(proc);
342 if (ptoa(npages +
343 pmap_wired_count(vm_map_pmap(&proc->p_vmspace->vm_map))) >
344 lim_cur(proc, RLIMIT_MEMLOCK)) {
345 PROC_UNLOCK(proc);
346 kfree(umem);
347 return ERR_PTR(-ENOMEM);
348 }
349 PROC_UNLOCK(proc);
350 if (npages + cnt.v_wire_count > vm_page_max_wired) {
351 kfree(umem);
352 return ERR_PTR(-EAGAIN);
353 }
354 error = vm_map_wire(&proc->p_vmspace->vm_map, start, end,
355 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES |
356 (umem->writable ? VM_MAP_WIRE_WRITE : 0));
357 if (error != KERN_SUCCESS) {
358 kfree(umem);
359 return ERR_PTR(-ENOMEM);
360 }
361
362 umem->context = context;
363 umem->length = size;
364 umem->offset = addr & ~PAGE_MASK;
365 umem->page_size = PAGE_SIZE;
366 umem->start = addr;
367 /*
368 * We ask for writable memory if any access flags other than
369 * "remote read" are set. "Local write" and "remote write"
370 * obviously require write access. "Remote atomic" can do
371 * things like fetch and add, which will modify memory, and
372 * "MW bind" can change permissions by binding a window.
373 */
374 umem->writable = !!(access & ~IB_ACCESS_REMOTE_READ);
375 umem->hugetlb = 0;
376 INIT_LIST_HEAD(&umem->chunk_list);
377
378 pmap = vm_map_pmap(&proc->p_vmspace->vm_map);
379 ret = 0;
380 while (npages) {
381 ents = min_t(int, npages, IB_UMEM_MAX_PAGE_CHUNK);
382 chunk = kmalloc(sizeof(*chunk) +
383 (sizeof(struct scatterlist) * ents),
384 GFP_KERNEL);
385 if (!chunk) {
386 ret = -ENOMEM;
387 goto out;
388 }
389
390 chunk->attrs = attrs;
391 chunk->nents = ents;
392 sg_init_table(&chunk->page_list[0], ents);
393 for (i = 0; i < chunk->nents; ++i) {
394 vm_paddr_t pa;
395
396 pa = pmap_extract(pmap, start);
397 if (pa == 0) {
398 ret = -ENOMEM;
399 kfree(chunk);
400 goto out;
401 }
402 sg_set_page(&chunk->page_list[i], PHYS_TO_VM_PAGE(pa),
403 PAGE_SIZE, 0);
404 npages--;
405 start += PAGE_SIZE;
406 }
407
408 chunk->nmap = ib_dma_map_sg_attrs(context->device,
409 &chunk->page_list[0],
410 chunk->nents,
411 DMA_BIDIRECTIONAL,
412 &attrs);
413 if (chunk->nmap != chunk->nents) {
414 kfree(chunk);
415 ret = -ENOMEM;
416 goto out;
417 }
418
419 list_add_tail(&chunk->list, &umem->chunk_list);
420 }
421
422 out:
423 if (ret < 0) {
424 __ib_umem_release(context->device, umem, 0);
425 kfree(umem);
426 }
427
428 return ret < 0 ? ERR_PTR(ret) : umem;
429 #endif
430 }
431 EXPORT_SYMBOL(ib_umem_get);
432
433 #ifdef __linux__
ib_umem_account(struct work_struct * work)434 static void ib_umem_account(struct work_struct *work)
435 {
436 struct ib_umem *umem = container_of(work, struct ib_umem, work);
437
438 down_write(&umem->mm->mmap_sem);
439 umem->mm->locked_vm -= umem->diff;
440 up_write(&umem->mm->mmap_sem);
441 mmput(umem->mm);
442 kfree(umem);
443 }
444 #endif
445
446 /**
447 * ib_umem_release - release memory pinned with ib_umem_get
448 * @umem: umem struct to release
449 */
ib_umem_release(struct ib_umem * umem)450 void ib_umem_release(struct ib_umem *umem)
451 {
452 #ifdef __linux__
453 struct ib_ucontext *context = umem->context;
454 struct mm_struct *mm;
455 unsigned long diff;
456
457 __ib_umem_release(umem->context->device, umem, 1);
458
459 mm = get_task_mm(current);
460 if (!mm) {
461 kfree(umem);
462 return;
463 }
464
465 diff = PAGE_ALIGN(umem->length + umem->offset) >> PAGE_SHIFT;
466
467 /*
468 * We may be called with the mm's mmap_sem already held. This
469 * can happen when a userspace munmap() is the call that drops
470 * the last reference to our file and calls our release
471 * method. If there are memory regions to destroy, we'll end
472 * up here and not be able to take the mmap_sem. In that case
473 * we defer the vm_locked accounting to the system workqueue.
474 */
475 if (context->closing) {
476 if (!down_write_trylock(&mm->mmap_sem)) {
477 INIT_WORK(&umem->work, ib_umem_account);
478 umem->mm = mm;
479 umem->diff = diff;
480
481 schedule_work(&umem->work);
482 return;
483 }
484 } else
485 down_write(&mm->mmap_sem);
486
487 current->mm->locked_vm -= diff;
488 up_write(&mm->mmap_sem);
489 mmput(mm);
490 #else
491 vm_offset_t addr, end, last, start;
492 vm_size_t size;
493 int error;
494
495 __ib_umem_release(umem->context->device, umem, 1);
496 if (umem->context->closing) {
497 kfree(umem);
498 return;
499 }
500 error = priv_check(curthread, PRIV_VM_MUNLOCK);
501 if (error)
502 return;
503 addr = umem->start;
504 size = umem->length;
505 last = addr + size;
506 start = addr & PAGE_MASK; /* Use the linux PAGE_MASK definition. */
507 end = roundup2(last, PAGE_SIZE); /* Use PAGE_MASK safe operation. */
508 vm_map_unwire(&curthread->td_proc->p_vmspace->vm_map, start, end,
509 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES);
510
511 #endif
512 kfree(umem);
513 }
514 EXPORT_SYMBOL(ib_umem_release);
515
ib_umem_page_count(struct ib_umem * umem)516 int ib_umem_page_count(struct ib_umem *umem)
517 {
518 struct ib_umem_chunk *chunk;
519 int shift;
520 int i;
521 int n;
522
523 shift = ilog2(umem->page_size);
524
525 n = 0;
526 list_for_each_entry(chunk, &umem->chunk_list, list)
527 for (i = 0; i < chunk->nmap; ++i)
528 n += sg_dma_len(&chunk->page_list[i]) >> shift;
529
530 return n;
531 }
532 EXPORT_SYMBOL(ib_umem_page_count);
533
534 /**********************************************/
535 /*
536 * Stub functions for contiguous pages -
537 * We currently do not support this feature
538 */
539 /**********************************************/
540
541 /**
542 * ib_cmem_release_contiguous_pages - release memory allocated by
543 * ib_cmem_alloc_contiguous_pages.
544 * @cmem: cmem struct to release
545 */
ib_cmem_release_contiguous_pages(struct ib_cmem * cmem)546 void ib_cmem_release_contiguous_pages(struct ib_cmem *cmem)
547 {
548 }
549 EXPORT_SYMBOL(ib_cmem_release_contiguous_pages);
550
551 /**
552 * * ib_cmem_alloc_contiguous_pages - allocate contiguous pages
553 * * @context: userspace context to allocate memory for
554 * * @total_size: total required size for that allocation.
555 * * @page_size_order: order of one contiguous page.
556 * */
ib_cmem_alloc_contiguous_pages(struct ib_ucontext * context,unsigned long total_size,unsigned long page_size_order)557 struct ib_cmem *ib_cmem_alloc_contiguous_pages(struct ib_ucontext *context,
558 unsigned long total_size,
559 unsigned long page_size_order)
560 {
561 return NULL;
562 }
563 EXPORT_SYMBOL(ib_cmem_alloc_contiguous_pages);
564
565 /**
566 * * ib_cmem_map_contiguous_pages_to_vma - map contiguous pages into VMA
567 * * @ib_cmem: cmem structure returned by ib_cmem_alloc_contiguous_pages
568 * * @vma: VMA to inject pages into.
569 * */
ib_cmem_map_contiguous_pages_to_vma(struct ib_cmem * ib_cmem,struct vm_area_struct * vma)570 int ib_cmem_map_contiguous_pages_to_vma(struct ib_cmem *ib_cmem,
571 struct vm_area_struct *vma)
572 {
573 return 0;
574 }
575 EXPORT_SYMBOL(ib_cmem_map_contiguous_pages_to_vma);
576