xref: /openbmc/linux/drivers/infiniband/sw/rxe/rxe_mr.c (revision a2818ee4)
1 /*
2  * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
3  * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *	- Redistributions of source code must retain the above
16  *	  copyright notice, this list of conditions and the following
17  *	  disclaimer.
18  *
19  *	- Redistributions in binary form must reproduce the above
20  *	  copyright notice, this list of conditions and the following
21  *	  disclaimer in the documentation and/or other materials
22  *	  provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #include "rxe.h"
35 #include "rxe_loc.h"
36 
37 /*
38  * lfsr (linear feedback shift register) with period 255
39  */
40 static u8 rxe_get_key(void)
41 {
42 	static u32 key = 1;
43 
44 	key = key << 1;
45 
46 	key |= (0 != (key & 0x100)) ^ (0 != (key & 0x10))
47 		^ (0 != (key & 0x80)) ^ (0 != (key & 0x40));
48 
49 	key &= 0xff;
50 
51 	return key;
52 }
53 
54 int mem_check_range(struct rxe_mem *mem, u64 iova, size_t length)
55 {
56 	switch (mem->type) {
57 	case RXE_MEM_TYPE_DMA:
58 		return 0;
59 
60 	case RXE_MEM_TYPE_MR:
61 	case RXE_MEM_TYPE_FMR:
62 		if (iova < mem->iova ||
63 		    length > mem->length ||
64 		    iova > mem->iova + mem->length - length)
65 			return -EFAULT;
66 		return 0;
67 
68 	default:
69 		return -EFAULT;
70 	}
71 }
72 
73 #define IB_ACCESS_REMOTE	(IB_ACCESS_REMOTE_READ		\
74 				| IB_ACCESS_REMOTE_WRITE	\
75 				| IB_ACCESS_REMOTE_ATOMIC)
76 
77 static void rxe_mem_init(int access, struct rxe_mem *mem)
78 {
79 	u32 lkey = mem->pelem.index << 8 | rxe_get_key();
80 	u32 rkey = (access & IB_ACCESS_REMOTE) ? lkey : 0;
81 
82 	if (mem->pelem.pool->type == RXE_TYPE_MR) {
83 		mem->ibmr.lkey		= lkey;
84 		mem->ibmr.rkey		= rkey;
85 	}
86 
87 	mem->lkey		= lkey;
88 	mem->rkey		= rkey;
89 	mem->state		= RXE_MEM_STATE_INVALID;
90 	mem->type		= RXE_MEM_TYPE_NONE;
91 	mem->map_shift		= ilog2(RXE_BUF_PER_MAP);
92 }
93 
94 void rxe_mem_cleanup(struct rxe_pool_entry *arg)
95 {
96 	struct rxe_mem *mem = container_of(arg, typeof(*mem), pelem);
97 	int i;
98 
99 	if (mem->umem)
100 		ib_umem_release(mem->umem);
101 
102 	if (mem->map) {
103 		for (i = 0; i < mem->num_map; i++)
104 			kfree(mem->map[i]);
105 
106 		kfree(mem->map);
107 	}
108 }
109 
110 static int rxe_mem_alloc(struct rxe_mem *mem, int num_buf)
111 {
112 	int i;
113 	int num_map;
114 	struct rxe_map **map = mem->map;
115 
116 	num_map = (num_buf + RXE_BUF_PER_MAP - 1) / RXE_BUF_PER_MAP;
117 
118 	mem->map = kmalloc_array(num_map, sizeof(*map), GFP_KERNEL);
119 	if (!mem->map)
120 		goto err1;
121 
122 	for (i = 0; i < num_map; i++) {
123 		mem->map[i] = kmalloc(sizeof(**map), GFP_KERNEL);
124 		if (!mem->map[i])
125 			goto err2;
126 	}
127 
128 	BUILD_BUG_ON(!is_power_of_2(RXE_BUF_PER_MAP));
129 
130 	mem->map_shift	= ilog2(RXE_BUF_PER_MAP);
131 	mem->map_mask	= RXE_BUF_PER_MAP - 1;
132 
133 	mem->num_buf = num_buf;
134 	mem->num_map = num_map;
135 	mem->max_buf = num_map * RXE_BUF_PER_MAP;
136 
137 	return 0;
138 
139 err2:
140 	for (i--; i >= 0; i--)
141 		kfree(mem->map[i]);
142 
143 	kfree(mem->map);
144 err1:
145 	return -ENOMEM;
146 }
147 
148 int rxe_mem_init_dma(struct rxe_pd *pd,
149 		     int access, struct rxe_mem *mem)
150 {
151 	rxe_mem_init(access, mem);
152 
153 	mem->pd			= pd;
154 	mem->access		= access;
155 	mem->state		= RXE_MEM_STATE_VALID;
156 	mem->type		= RXE_MEM_TYPE_DMA;
157 
158 	return 0;
159 }
160 
161 int rxe_mem_init_user(struct rxe_pd *pd, u64 start,
162 		      u64 length, u64 iova, int access, struct ib_udata *udata,
163 		      struct rxe_mem *mem)
164 {
165 	int			entry;
166 	struct rxe_map		**map;
167 	struct rxe_phys_buf	*buf = NULL;
168 	struct ib_umem		*umem;
169 	struct scatterlist	*sg;
170 	int			num_buf;
171 	void			*vaddr;
172 	int err;
173 
174 	umem = ib_umem_get(pd->ibpd.uobject->context, start, length, access, 0);
175 	if (IS_ERR(umem)) {
176 		pr_warn("err %d from rxe_umem_get\n",
177 			(int)PTR_ERR(umem));
178 		err = -EINVAL;
179 		goto err1;
180 	}
181 
182 	mem->umem = umem;
183 	num_buf = umem->nmap;
184 
185 	rxe_mem_init(access, mem);
186 
187 	err = rxe_mem_alloc(mem, num_buf);
188 	if (err) {
189 		pr_warn("err %d from rxe_mem_alloc\n", err);
190 		ib_umem_release(umem);
191 		goto err1;
192 	}
193 
194 	mem->page_shift		= umem->page_shift;
195 	mem->page_mask		= BIT(umem->page_shift) - 1;
196 
197 	num_buf			= 0;
198 	map			= mem->map;
199 	if (length > 0) {
200 		buf = map[0]->buf;
201 
202 		for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
203 			vaddr = page_address(sg_page(sg));
204 			if (!vaddr) {
205 				pr_warn("null vaddr\n");
206 				err = -ENOMEM;
207 				goto err1;
208 			}
209 
210 			buf->addr = (uintptr_t)vaddr;
211 			buf->size = BIT(umem->page_shift);
212 			num_buf++;
213 			buf++;
214 
215 			if (num_buf >= RXE_BUF_PER_MAP) {
216 				map++;
217 				buf = map[0]->buf;
218 				num_buf = 0;
219 			}
220 		}
221 	}
222 
223 	mem->pd			= pd;
224 	mem->umem		= umem;
225 	mem->access		= access;
226 	mem->length		= length;
227 	mem->iova		= iova;
228 	mem->va			= start;
229 	mem->offset		= ib_umem_offset(umem);
230 	mem->state		= RXE_MEM_STATE_VALID;
231 	mem->type		= RXE_MEM_TYPE_MR;
232 
233 	return 0;
234 
235 err1:
236 	return err;
237 }
238 
239 int rxe_mem_init_fast(struct rxe_pd *pd,
240 		      int max_pages, struct rxe_mem *mem)
241 {
242 	int err;
243 
244 	rxe_mem_init(0, mem);
245 
246 	/* In fastreg, we also set the rkey */
247 	mem->ibmr.rkey = mem->ibmr.lkey;
248 
249 	err = rxe_mem_alloc(mem, max_pages);
250 	if (err)
251 		goto err1;
252 
253 	mem->pd			= pd;
254 	mem->max_buf		= max_pages;
255 	mem->state		= RXE_MEM_STATE_FREE;
256 	mem->type		= RXE_MEM_TYPE_MR;
257 
258 	return 0;
259 
260 err1:
261 	return err;
262 }
263 
264 static void lookup_iova(
265 	struct rxe_mem	*mem,
266 	u64			iova,
267 	int			*m_out,
268 	int			*n_out,
269 	size_t			*offset_out)
270 {
271 	size_t			offset = iova - mem->iova + mem->offset;
272 	int			map_index;
273 	int			buf_index;
274 	u64			length;
275 
276 	if (likely(mem->page_shift)) {
277 		*offset_out = offset & mem->page_mask;
278 		offset >>= mem->page_shift;
279 		*n_out = offset & mem->map_mask;
280 		*m_out = offset >> mem->map_shift;
281 	} else {
282 		map_index = 0;
283 		buf_index = 0;
284 
285 		length = mem->map[map_index]->buf[buf_index].size;
286 
287 		while (offset >= length) {
288 			offset -= length;
289 			buf_index++;
290 
291 			if (buf_index == RXE_BUF_PER_MAP) {
292 				map_index++;
293 				buf_index = 0;
294 			}
295 			length = mem->map[map_index]->buf[buf_index].size;
296 		}
297 
298 		*m_out = map_index;
299 		*n_out = buf_index;
300 		*offset_out = offset;
301 	}
302 }
303 
304 void *iova_to_vaddr(struct rxe_mem *mem, u64 iova, int length)
305 {
306 	size_t offset;
307 	int m, n;
308 	void *addr;
309 
310 	if (mem->state != RXE_MEM_STATE_VALID) {
311 		pr_warn("mem not in valid state\n");
312 		addr = NULL;
313 		goto out;
314 	}
315 
316 	if (!mem->map) {
317 		addr = (void *)(uintptr_t)iova;
318 		goto out;
319 	}
320 
321 	if (mem_check_range(mem, iova, length)) {
322 		pr_warn("range violation\n");
323 		addr = NULL;
324 		goto out;
325 	}
326 
327 	lookup_iova(mem, iova, &m, &n, &offset);
328 
329 	if (offset + length > mem->map[m]->buf[n].size) {
330 		pr_warn("crosses page boundary\n");
331 		addr = NULL;
332 		goto out;
333 	}
334 
335 	addr = (void *)(uintptr_t)mem->map[m]->buf[n].addr + offset;
336 
337 out:
338 	return addr;
339 }
340 
341 /* copy data from a range (vaddr, vaddr+length-1) to or from
342  * a mem object starting at iova. Compute incremental value of
343  * crc32 if crcp is not zero. caller must hold a reference to mem
344  */
345 int rxe_mem_copy(struct rxe_mem *mem, u64 iova, void *addr, int length,
346 		 enum copy_direction dir, u32 *crcp)
347 {
348 	int			err;
349 	int			bytes;
350 	u8			*va;
351 	struct rxe_map		**map;
352 	struct rxe_phys_buf	*buf;
353 	int			m;
354 	int			i;
355 	size_t			offset;
356 	u32			crc = crcp ? (*crcp) : 0;
357 
358 	if (length == 0)
359 		return 0;
360 
361 	if (mem->type == RXE_MEM_TYPE_DMA) {
362 		u8 *src, *dest;
363 
364 		src  = (dir == to_mem_obj) ?
365 			addr : ((void *)(uintptr_t)iova);
366 
367 		dest = (dir == to_mem_obj) ?
368 			((void *)(uintptr_t)iova) : addr;
369 
370 		memcpy(dest, src, length);
371 
372 		if (crcp)
373 			*crcp = rxe_crc32(to_rdev(mem->pd->ibpd.device),
374 					*crcp, dest, length);
375 
376 		return 0;
377 	}
378 
379 	WARN_ON_ONCE(!mem->map);
380 
381 	err = mem_check_range(mem, iova, length);
382 	if (err) {
383 		err = -EFAULT;
384 		goto err1;
385 	}
386 
387 	lookup_iova(mem, iova, &m, &i, &offset);
388 
389 	map	= mem->map + m;
390 	buf	= map[0]->buf + i;
391 
392 	while (length > 0) {
393 		u8 *src, *dest;
394 
395 		va	= (u8 *)(uintptr_t)buf->addr + offset;
396 		src  = (dir == to_mem_obj) ? addr : va;
397 		dest = (dir == to_mem_obj) ? va : addr;
398 
399 		bytes	= buf->size - offset;
400 
401 		if (bytes > length)
402 			bytes = length;
403 
404 		memcpy(dest, src, bytes);
405 
406 		if (crcp)
407 			crc = rxe_crc32(to_rdev(mem->pd->ibpd.device),
408 					crc, dest, bytes);
409 
410 		length	-= bytes;
411 		addr	+= bytes;
412 
413 		offset	= 0;
414 		buf++;
415 		i++;
416 
417 		if (i == RXE_BUF_PER_MAP) {
418 			i = 0;
419 			map++;
420 			buf = map[0]->buf;
421 		}
422 	}
423 
424 	if (crcp)
425 		*crcp = crc;
426 
427 	return 0;
428 
429 err1:
430 	return err;
431 }
432 
433 /* copy data in or out of a wqe, i.e. sg list
434  * under the control of a dma descriptor
435  */
436 int copy_data(
437 	struct rxe_pd		*pd,
438 	int			access,
439 	struct rxe_dma_info	*dma,
440 	void			*addr,
441 	int			length,
442 	enum copy_direction	dir,
443 	u32			*crcp)
444 {
445 	int			bytes;
446 	struct rxe_sge		*sge	= &dma->sge[dma->cur_sge];
447 	int			offset	= dma->sge_offset;
448 	int			resid	= dma->resid;
449 	struct rxe_mem		*mem	= NULL;
450 	u64			iova;
451 	int			err;
452 
453 	if (length == 0)
454 		return 0;
455 
456 	if (length > resid) {
457 		err = -EINVAL;
458 		goto err2;
459 	}
460 
461 	if (sge->length && (offset < sge->length)) {
462 		mem = lookup_mem(pd, access, sge->lkey, lookup_local);
463 		if (!mem) {
464 			err = -EINVAL;
465 			goto err1;
466 		}
467 	}
468 
469 	while (length > 0) {
470 		bytes = length;
471 
472 		if (offset >= sge->length) {
473 			if (mem) {
474 				rxe_drop_ref(mem);
475 				mem = NULL;
476 			}
477 			sge++;
478 			dma->cur_sge++;
479 			offset = 0;
480 
481 			if (dma->cur_sge >= dma->num_sge) {
482 				err = -ENOSPC;
483 				goto err2;
484 			}
485 
486 			if (sge->length) {
487 				mem = lookup_mem(pd, access, sge->lkey,
488 						 lookup_local);
489 				if (!mem) {
490 					err = -EINVAL;
491 					goto err1;
492 				}
493 			} else {
494 				continue;
495 			}
496 		}
497 
498 		if (bytes > sge->length - offset)
499 			bytes = sge->length - offset;
500 
501 		if (bytes > 0) {
502 			iova = sge->addr + offset;
503 
504 			err = rxe_mem_copy(mem, iova, addr, bytes, dir, crcp);
505 			if (err)
506 				goto err2;
507 
508 			offset	+= bytes;
509 			resid	-= bytes;
510 			length	-= bytes;
511 			addr	+= bytes;
512 		}
513 	}
514 
515 	dma->sge_offset = offset;
516 	dma->resid	= resid;
517 
518 	if (mem)
519 		rxe_drop_ref(mem);
520 
521 	return 0;
522 
523 err2:
524 	if (mem)
525 		rxe_drop_ref(mem);
526 err1:
527 	return err;
528 }
529 
530 int advance_dma_data(struct rxe_dma_info *dma, unsigned int length)
531 {
532 	struct rxe_sge		*sge	= &dma->sge[dma->cur_sge];
533 	int			offset	= dma->sge_offset;
534 	int			resid	= dma->resid;
535 
536 	while (length) {
537 		unsigned int bytes;
538 
539 		if (offset >= sge->length) {
540 			sge++;
541 			dma->cur_sge++;
542 			offset = 0;
543 			if (dma->cur_sge >= dma->num_sge)
544 				return -ENOSPC;
545 		}
546 
547 		bytes = length;
548 
549 		if (bytes > sge->length - offset)
550 			bytes = sge->length - offset;
551 
552 		offset	+= bytes;
553 		resid	-= bytes;
554 		length	-= bytes;
555 	}
556 
557 	dma->sge_offset = offset;
558 	dma->resid	= resid;
559 
560 	return 0;
561 }
562 
563 /* (1) find the mem (mr or mw) corresponding to lkey/rkey
564  *     depending on lookup_type
565  * (2) verify that the (qp) pd matches the mem pd
566  * (3) verify that the mem can support the requested access
567  * (4) verify that mem state is valid
568  */
569 struct rxe_mem *lookup_mem(struct rxe_pd *pd, int access, u32 key,
570 			   enum lookup_type type)
571 {
572 	struct rxe_mem *mem;
573 	struct rxe_dev *rxe = to_rdev(pd->ibpd.device);
574 	int index = key >> 8;
575 
576 	mem = rxe_pool_get_index(&rxe->mr_pool, index);
577 	if (!mem)
578 		return NULL;
579 
580 	if (unlikely((type == lookup_local && mem->lkey != key) ||
581 		     (type == lookup_remote && mem->rkey != key) ||
582 		     mem->pd != pd ||
583 		     (access && !(access & mem->access)) ||
584 		     mem->state != RXE_MEM_STATE_VALID)) {
585 		rxe_drop_ref(mem);
586 		mem = NULL;
587 	}
588 
589 	return mem;
590 }
591 
592 int rxe_mem_map_pages(struct rxe_dev *rxe, struct rxe_mem *mem,
593 		      u64 *page, int num_pages, u64 iova)
594 {
595 	int i;
596 	int num_buf;
597 	int err;
598 	struct rxe_map **map;
599 	struct rxe_phys_buf *buf;
600 	int page_size;
601 
602 	if (num_pages > mem->max_buf) {
603 		err = -EINVAL;
604 		goto err1;
605 	}
606 
607 	num_buf		= 0;
608 	page_size	= 1 << mem->page_shift;
609 	map		= mem->map;
610 	buf		= map[0]->buf;
611 
612 	for (i = 0; i < num_pages; i++) {
613 		buf->addr = *page++;
614 		buf->size = page_size;
615 		buf++;
616 		num_buf++;
617 
618 		if (num_buf == RXE_BUF_PER_MAP) {
619 			map++;
620 			buf = map[0]->buf;
621 			num_buf = 0;
622 		}
623 	}
624 
625 	mem->iova	= iova;
626 	mem->va		= iova;
627 	mem->length	= num_pages << mem->page_shift;
628 	mem->state	= RXE_MEM_STATE_VALID;
629 
630 	return 0;
631 
632 err1:
633 	return err;
634 }
635