1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2/*
3 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
4 * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
5 */
6
7#include <linux/libnvdimm.h>
8
9#include "rxe.h"
10#include "rxe_loc.h"
11
12/* Return a random 8 bit key value that is
13 * different than the last_key. Set last_key to -1
14 * if this is the first key for an MR or MW
15 */
16u8 rxe_get_next_key(u32 last_key)
17{
18	u8 key;
19
20	do {
21		get_random_bytes(&key, 1);
22	} while (key == last_key);
23
24	return key;
25}
26
27int mr_check_range(struct rxe_mr *mr, u64 iova, size_t length)
28{
29	switch (mr->ibmr.type) {
30	case IB_MR_TYPE_DMA:
31		return 0;
32
33	case IB_MR_TYPE_USER:
34	case IB_MR_TYPE_MEM_REG:
35		if (iova < mr->ibmr.iova ||
36		    iova + length > mr->ibmr.iova + mr->ibmr.length) {
37			rxe_dbg_mr(mr, "iova/length out of range\n");
38			return -EINVAL;
39		}
40		return 0;
41
42	default:
43		rxe_dbg_mr(mr, "mr type not supported\n");
44		return -EINVAL;
45	}
46}
47
48static void rxe_mr_init(int access, struct rxe_mr *mr)
49{
50	u32 key = mr->elem.index << 8 | rxe_get_next_key(-1);
51
52	/* set ibmr->l/rkey and also copy into private l/rkey
53	 * for user MRs these will always be the same
54	 * for cases where caller 'owns' the key portion
55	 * they may be different until REG_MR WQE is executed.
56	 */
57	mr->lkey = mr->ibmr.lkey = key;
58	mr->rkey = mr->ibmr.rkey = key;
59
60	mr->access = access;
61	mr->ibmr.page_size = PAGE_SIZE;
62	mr->page_mask = PAGE_MASK;
63	mr->page_shift = PAGE_SHIFT;
64	mr->state = RXE_MR_STATE_INVALID;
65}
66
67void rxe_mr_init_dma(int access, struct rxe_mr *mr)
68{
69	rxe_mr_init(access, mr);
70
71	mr->state = RXE_MR_STATE_VALID;
72	mr->ibmr.type = IB_MR_TYPE_DMA;
73}
74
75static unsigned long rxe_mr_iova_to_index(struct rxe_mr *mr, u64 iova)
76{
77	return (iova >> mr->page_shift) - (mr->ibmr.iova >> mr->page_shift);
78}
79
80static unsigned long rxe_mr_iova_to_page_offset(struct rxe_mr *mr, u64 iova)
81{
82	return iova & (mr_page_size(mr) - 1);
83}
84
85static bool is_pmem_page(struct page *pg)
86{
87	unsigned long paddr = page_to_phys(pg);
88
89	return REGION_INTERSECTS ==
90	       region_intersects(paddr, PAGE_SIZE, IORESOURCE_MEM,
91				 IORES_DESC_PERSISTENT_MEMORY);
92}
93
94static int rxe_mr_fill_pages_from_sgt(struct rxe_mr *mr, struct sg_table *sgt)
95{
96	XA_STATE(xas, &mr->page_list, 0);
97	struct sg_page_iter sg_iter;
98	struct page *page;
99	bool persistent = !!(mr->access & IB_ACCESS_FLUSH_PERSISTENT);
100
101	__sg_page_iter_start(&sg_iter, sgt->sgl, sgt->orig_nents, 0);
102	if (!__sg_page_iter_next(&sg_iter))
103		return 0;
104
105	do {
106		xas_lock(&xas);
107		while (true) {
108			page = sg_page_iter_page(&sg_iter);
109
110			if (persistent && !is_pmem_page(page)) {
111				rxe_dbg_mr(mr, "Page can't be persistent\n");
112				xas_set_err(&xas, -EINVAL);
113				break;
114			}
115
116			xas_store(&xas, page);
117			if (xas_error(&xas))
118				break;
119			xas_next(&xas);
120			if (!__sg_page_iter_next(&sg_iter))
121				break;
122		}
123		xas_unlock(&xas);
124	} while (xas_nomem(&xas, GFP_KERNEL));
125
126	return xas_error(&xas);
127}
128
129int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length,
130		     int access, struct rxe_mr *mr)
131{
132	struct ib_umem *umem;
133	int err;
134
135	rxe_mr_init(access, mr);
136
137	xa_init(&mr->page_list);
138
139	umem = ib_umem_get(&rxe->ib_dev, start, length, access);
140	if (IS_ERR(umem)) {
141		rxe_dbg_mr(mr, "Unable to pin memory region err = %d\n",
142			(int)PTR_ERR(umem));
143		return PTR_ERR(umem);
144	}
145
146	err = rxe_mr_fill_pages_from_sgt(mr, &umem->sgt_append.sgt);
147	if (err) {
148		ib_umem_release(umem);
149		return err;
150	}
151
152	mr->umem = umem;
153	mr->ibmr.type = IB_MR_TYPE_USER;
154	mr->state = RXE_MR_STATE_VALID;
155
156	return 0;
157}
158
159static int rxe_mr_alloc(struct rxe_mr *mr, int num_buf)
160{
161	XA_STATE(xas, &mr->page_list, 0);
162	int i = 0;
163	int err;
164
165	xa_init(&mr->page_list);
166
167	do {
168		xas_lock(&xas);
169		while (i != num_buf) {
170			xas_store(&xas, XA_ZERO_ENTRY);
171			if (xas_error(&xas))
172				break;
173			xas_next(&xas);
174			i++;
175		}
176		xas_unlock(&xas);
177	} while (xas_nomem(&xas, GFP_KERNEL));
178
179	err = xas_error(&xas);
180	if (err)
181		return err;
182
183	mr->num_buf = num_buf;
184
185	return 0;
186}
187
188int rxe_mr_init_fast(int max_pages, struct rxe_mr *mr)
189{
190	int err;
191
192	/* always allow remote access for FMRs */
193	rxe_mr_init(RXE_ACCESS_REMOTE, mr);
194
195	err = rxe_mr_alloc(mr, max_pages);
196	if (err)
197		goto err1;
198
199	mr->state = RXE_MR_STATE_FREE;
200	mr->ibmr.type = IB_MR_TYPE_MEM_REG;
201
202	return 0;
203
204err1:
205	return err;
206}
207
208static int rxe_set_page(struct ib_mr *ibmr, u64 dma_addr)
209{
210	struct rxe_mr *mr = to_rmr(ibmr);
211	struct page *page = ib_virt_dma_to_page(dma_addr);
212	bool persistent = !!(mr->access & IB_ACCESS_FLUSH_PERSISTENT);
213	int err;
214
215	if (persistent && !is_pmem_page(page)) {
216		rxe_dbg_mr(mr, "Page cannot be persistent\n");
217		return -EINVAL;
218	}
219
220	if (unlikely(mr->nbuf == mr->num_buf))
221		return -ENOMEM;
222
223	err = xa_err(xa_store(&mr->page_list, mr->nbuf, page, GFP_KERNEL));
224	if (err)
225		return err;
226
227	mr->nbuf++;
228	return 0;
229}
230
231int rxe_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sgl,
232		  int sg_nents, unsigned int *sg_offset)
233{
234	struct rxe_mr *mr = to_rmr(ibmr);
235	unsigned int page_size = mr_page_size(mr);
236
237	mr->nbuf = 0;
238	mr->page_shift = ilog2(page_size);
239	mr->page_mask = ~((u64)page_size - 1);
240	mr->page_offset = mr->ibmr.iova & (page_size - 1);
241
242	return ib_sg_to_pages(ibmr, sgl, sg_nents, sg_offset, rxe_set_page);
243}
244
245static int rxe_mr_copy_xarray(struct rxe_mr *mr, u64 iova, void *addr,
246			      unsigned int length, enum rxe_mr_copy_dir dir)
247{
248	unsigned int page_offset = rxe_mr_iova_to_page_offset(mr, iova);
249	unsigned long index = rxe_mr_iova_to_index(mr, iova);
250	unsigned int bytes;
251	struct page *page;
252	void *va;
253
254	while (length) {
255		page = xa_load(&mr->page_list, index);
256		if (!page)
257			return -EFAULT;
258
259		bytes = min_t(unsigned int, length,
260				mr_page_size(mr) - page_offset);
261		va = kmap_local_page(page);
262		if (dir == RXE_FROM_MR_OBJ)
263			memcpy(addr, va + page_offset, bytes);
264		else
265			memcpy(va + page_offset, addr, bytes);
266		kunmap_local(va);
267
268		page_offset = 0;
269		addr += bytes;
270		length -= bytes;
271		index++;
272	}
273
274	return 0;
275}
276
277static void rxe_mr_copy_dma(struct rxe_mr *mr, u64 dma_addr, void *addr,
278			    unsigned int length, enum rxe_mr_copy_dir dir)
279{
280	unsigned int page_offset = dma_addr & (PAGE_SIZE - 1);
281	unsigned int bytes;
282	struct page *page;
283	u8 *va;
284
285	while (length) {
286		page = ib_virt_dma_to_page(dma_addr);
287		bytes = min_t(unsigned int, length,
288				PAGE_SIZE - page_offset);
289		va = kmap_local_page(page);
290
291		if (dir == RXE_TO_MR_OBJ)
292			memcpy(va + page_offset, addr, bytes);
293		else
294			memcpy(addr, va + page_offset, bytes);
295
296		kunmap_local(va);
297		page_offset = 0;
298		dma_addr += bytes;
299		addr += bytes;
300		length -= bytes;
301	}
302}
303
304int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr,
305		unsigned int length, enum rxe_mr_copy_dir dir)
306{
307	int err;
308
309	if (length == 0)
310		return 0;
311
312	if (WARN_ON(!mr))
313		return -EINVAL;
314
315	if (mr->ibmr.type == IB_MR_TYPE_DMA) {
316		rxe_mr_copy_dma(mr, iova, addr, length, dir);
317		return 0;
318	}
319
320	err = mr_check_range(mr, iova, length);
321	if (unlikely(err)) {
322		rxe_dbg_mr(mr, "iova out of range\n");
323		return err;
324	}
325
326	return rxe_mr_copy_xarray(mr, iova, addr, length, dir);
327}
328
329/* copy data in or out of a wqe, i.e. sg list
330 * under the control of a dma descriptor
331 */
332int copy_data(
333	struct rxe_pd		*pd,
334	int			access,
335	struct rxe_dma_info	*dma,
336	void			*addr,
337	int			length,
338	enum rxe_mr_copy_dir	dir)
339{
340	int			bytes;
341	struct rxe_sge		*sge	= &dma->sge[dma->cur_sge];
342	int			offset	= dma->sge_offset;
343	int			resid	= dma->resid;
344	struct rxe_mr		*mr	= NULL;
345	u64			iova;
346	int			err;
347
348	if (length == 0)
349		return 0;
350
351	if (length > resid) {
352		err = -EINVAL;
353		goto err2;
354	}
355
356	if (sge->length && (offset < sge->length)) {
357		mr = lookup_mr(pd, access, sge->lkey, RXE_LOOKUP_LOCAL);
358		if (!mr) {
359			err = -EINVAL;
360			goto err1;
361		}
362	}
363
364	while (length > 0) {
365		bytes = length;
366
367		if (offset >= sge->length) {
368			if (mr) {
369				rxe_put(mr);
370				mr = NULL;
371			}
372			sge++;
373			dma->cur_sge++;
374			offset = 0;
375
376			if (dma->cur_sge >= dma->num_sge) {
377				err = -ENOSPC;
378				goto err2;
379			}
380
381			if (sge->length) {
382				mr = lookup_mr(pd, access, sge->lkey,
383					       RXE_LOOKUP_LOCAL);
384				if (!mr) {
385					err = -EINVAL;
386					goto err1;
387				}
388			} else {
389				continue;
390			}
391		}
392
393		if (bytes > sge->length - offset)
394			bytes = sge->length - offset;
395
396		if (bytes > 0) {
397			iova = sge->addr + offset;
398			err = rxe_mr_copy(mr, iova, addr, bytes, dir);
399			if (err)
400				goto err2;
401
402			offset	+= bytes;
403			resid	-= bytes;
404			length	-= bytes;
405			addr	+= bytes;
406		}
407	}
408
409	dma->sge_offset = offset;
410	dma->resid	= resid;
411
412	if (mr)
413		rxe_put(mr);
414
415	return 0;
416
417err2:
418	if (mr)
419		rxe_put(mr);
420err1:
421	return err;
422}
423
424int rxe_flush_pmem_iova(struct rxe_mr *mr, u64 iova, unsigned int length)
425{
426	unsigned int page_offset;
427	unsigned long index;
428	struct page *page;
429	unsigned int bytes;
430	int err;
431	u8 *va;
432
433	/* mr must be valid even if length is zero */
434	if (WARN_ON(!mr))
435		return -EINVAL;
436
437	if (length == 0)
438		return 0;
439
440	if (mr->ibmr.type == IB_MR_TYPE_DMA)
441		return -EFAULT;
442
443	err = mr_check_range(mr, iova, length);
444	if (err)
445		return err;
446
447	while (length > 0) {
448		index = rxe_mr_iova_to_index(mr, iova);
449		page = xa_load(&mr->page_list, index);
450		page_offset = rxe_mr_iova_to_page_offset(mr, iova);
451		if (!page)
452			return -EFAULT;
453		bytes = min_t(unsigned int, length,
454				mr_page_size(mr) - page_offset);
455
456		va = kmap_local_page(page);
457		arch_wb_cache_pmem(va + page_offset, bytes);
458		kunmap_local(va);
459
460		length -= bytes;
461		iova += bytes;
462		page_offset = 0;
463	}
464
465	return 0;
466}
467
468/* Guarantee atomicity of atomic operations at the machine level. */
469static DEFINE_SPINLOCK(atomic_ops_lock);
470
471int rxe_mr_do_atomic_op(struct rxe_mr *mr, u64 iova, int opcode,
472			u64 compare, u64 swap_add, u64 *orig_val)
473{
474	unsigned int page_offset;
475	struct page *page;
476	u64 value;
477	u64 *va;
478
479	if (unlikely(mr->state != RXE_MR_STATE_VALID)) {
480		rxe_dbg_mr(mr, "mr not in valid state\n");
481		return RESPST_ERR_RKEY_VIOLATION;
482	}
483
484	if (mr->ibmr.type == IB_MR_TYPE_DMA) {
485		page_offset = iova & (PAGE_SIZE - 1);
486		page = ib_virt_dma_to_page(iova);
487	} else {
488		unsigned long index;
489		int err;
490
491		err = mr_check_range(mr, iova, sizeof(value));
492		if (err) {
493			rxe_dbg_mr(mr, "iova out of range\n");
494			return RESPST_ERR_RKEY_VIOLATION;
495		}
496		page_offset = rxe_mr_iova_to_page_offset(mr, iova);
497		index = rxe_mr_iova_to_index(mr, iova);
498		page = xa_load(&mr->page_list, index);
499		if (!page)
500			return RESPST_ERR_RKEY_VIOLATION;
501	}
502
503	if (unlikely(page_offset & 0x7)) {
504		rxe_dbg_mr(mr, "iova not aligned\n");
505		return RESPST_ERR_MISALIGNED_ATOMIC;
506	}
507
508	va = kmap_local_page(page);
509
510	spin_lock_bh(&atomic_ops_lock);
511	value = *orig_val = va[page_offset >> 3];
512
513	if (opcode == IB_OPCODE_RC_COMPARE_SWAP) {
514		if (value == compare)
515			va[page_offset >> 3] = swap_add;
516	} else {
517		value += swap_add;
518		va[page_offset >> 3] = value;
519	}
520	spin_unlock_bh(&atomic_ops_lock);
521
522	kunmap_local(va);
523
524	return 0;
525}
526
527#if defined CONFIG_64BIT
528/* only implemented or called for 64 bit architectures */
529int rxe_mr_do_atomic_write(struct rxe_mr *mr, u64 iova, u64 value)
530{
531	unsigned int page_offset;
532	struct page *page;
533	u64 *va;
534
535	/* See IBA oA19-28 */
536	if (unlikely(mr->state != RXE_MR_STATE_VALID)) {
537		rxe_dbg_mr(mr, "mr not in valid state\n");
538		return RESPST_ERR_RKEY_VIOLATION;
539	}
540
541	if (mr->ibmr.type == IB_MR_TYPE_DMA) {
542		page_offset = iova & (PAGE_SIZE - 1);
543		page = ib_virt_dma_to_page(iova);
544	} else {
545		unsigned long index;
546		int err;
547
548		/* See IBA oA19-28 */
549		err = mr_check_range(mr, iova, sizeof(value));
550		if (unlikely(err)) {
551			rxe_dbg_mr(mr, "iova out of range\n");
552			return RESPST_ERR_RKEY_VIOLATION;
553		}
554		page_offset = rxe_mr_iova_to_page_offset(mr, iova);
555		index = rxe_mr_iova_to_index(mr, iova);
556		page = xa_load(&mr->page_list, index);
557		if (!page)
558			return RESPST_ERR_RKEY_VIOLATION;
559	}
560
561	/* See IBA A19.4.2 */
562	if (unlikely(page_offset & 0x7)) {
563		rxe_dbg_mr(mr, "misaligned address\n");
564		return RESPST_ERR_MISALIGNED_ATOMIC;
565	}
566
567	va = kmap_local_page(page);
568
569	/* Do atomic write after all prior operations have completed */
570	smp_store_release(&va[page_offset >> 3], value);
571
572	kunmap_local(va);
573
574	return 0;
575}
576#else
577int rxe_mr_do_atomic_write(struct rxe_mr *mr, u64 iova, u64 value)
578{
579	return RESPST_ERR_UNSUPPORTED_OPCODE;
580}
581#endif
582
583int advance_dma_data(struct rxe_dma_info *dma, unsigned int length)
584{
585	struct rxe_sge		*sge	= &dma->sge[dma->cur_sge];
586	int			offset	= dma->sge_offset;
587	int			resid	= dma->resid;
588
589	while (length) {
590		unsigned int bytes;
591
592		if (offset >= sge->length) {
593			sge++;
594			dma->cur_sge++;
595			offset = 0;
596			if (dma->cur_sge >= dma->num_sge)
597				return -ENOSPC;
598		}
599
600		bytes = length;
601
602		if (bytes > sge->length - offset)
603			bytes = sge->length - offset;
604
605		offset	+= bytes;
606		resid	-= bytes;
607		length	-= bytes;
608	}
609
610	dma->sge_offset = offset;
611	dma->resid	= resid;
612
613	return 0;
614}
615
616struct rxe_mr *lookup_mr(struct rxe_pd *pd, int access, u32 key,
617			 enum rxe_mr_lookup_type type)
618{
619	struct rxe_mr *mr;
620	struct rxe_dev *rxe = to_rdev(pd->ibpd.device);
621	int index = key >> 8;
622
623	mr = rxe_pool_get_index(&rxe->mr_pool, index);
624	if (!mr)
625		return NULL;
626
627	if (unlikely((type == RXE_LOOKUP_LOCAL && mr->lkey != key) ||
628		     (type == RXE_LOOKUP_REMOTE && mr->rkey != key) ||
629		     mr_pd(mr) != pd || ((access & mr->access) != access) ||
630		     mr->state != RXE_MR_STATE_VALID)) {
631		rxe_put(mr);
632		mr = NULL;
633	}
634
635	return mr;
636}
637
638int rxe_invalidate_mr(struct rxe_qp *qp, u32 key)
639{
640	struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
641	struct rxe_mr *mr;
642	int remote;
643	int ret;
644
645	mr = rxe_pool_get_index(&rxe->mr_pool, key >> 8);
646	if (!mr) {
647		rxe_dbg_qp(qp, "No MR for key %#x\n", key);
648		ret = -EINVAL;
649		goto err;
650	}
651
652	remote = mr->access & RXE_ACCESS_REMOTE;
653	if (remote ? (key != mr->rkey) : (key != mr->lkey)) {
654		rxe_dbg_mr(mr, "wr key (%#x) doesn't match mr key (%#x)\n",
655			key, (remote ? mr->rkey : mr->lkey));
656		ret = -EINVAL;
657		goto err_drop_ref;
658	}
659
660	if (atomic_read(&mr->num_mw) > 0) {
661		rxe_dbg_mr(mr, "Attempt to invalidate an MR while bound to MWs\n");
662		ret = -EINVAL;
663		goto err_drop_ref;
664	}
665
666	if (unlikely(mr->ibmr.type != IB_MR_TYPE_MEM_REG)) {
667		rxe_dbg_mr(mr, "Type (%d) is wrong\n", mr->ibmr.type);
668		ret = -EINVAL;
669		goto err_drop_ref;
670	}
671
672	mr->state = RXE_MR_STATE_FREE;
673	ret = 0;
674
675err_drop_ref:
676	rxe_put(mr);
677err:
678	return ret;
679}
680
681/* user can (re)register fast MR by executing a REG_MR WQE.
682 * user is expected to hold a reference on the ib mr until the
683 * WQE completes.
684 * Once a fast MR is created this is the only way to change the
685 * private keys. It is the responsibility of the user to maintain
686 * the ib mr keys in sync with rxe mr keys.
687 */
688int rxe_reg_fast_mr(struct rxe_qp *qp, struct rxe_send_wqe *wqe)
689{
690	struct rxe_mr *mr = to_rmr(wqe->wr.wr.reg.mr);
691	u32 key = wqe->wr.wr.reg.key;
692	u32 access = wqe->wr.wr.reg.access;
693
694	/* user can only register MR in free state */
695	if (unlikely(mr->state != RXE_MR_STATE_FREE)) {
696		rxe_dbg_mr(mr, "mr->lkey = 0x%x not free\n", mr->lkey);
697		return -EINVAL;
698	}
699
700	/* user can only register mr with qp in same protection domain */
701	if (unlikely(qp->ibqp.pd != mr->ibmr.pd)) {
702		rxe_dbg_mr(mr, "qp->pd and mr->pd don't match\n");
703		return -EINVAL;
704	}
705
706	/* user is only allowed to change key portion of l/rkey */
707	if (unlikely((mr->lkey & ~0xff) != (key & ~0xff))) {
708		rxe_dbg_mr(mr, "key = 0x%x has wrong index mr->lkey = 0x%x\n",
709			key, mr->lkey);
710		return -EINVAL;
711	}
712
713	mr->access = access;
714	mr->lkey = key;
715	mr->rkey = key;
716	mr->ibmr.iova = wqe->wr.wr.reg.mr->iova;
717	mr->state = RXE_MR_STATE_VALID;
718
719	return 0;
720}
721
722void rxe_mr_cleanup(struct rxe_pool_elem *elem)
723{
724	struct rxe_mr *mr = container_of(elem, typeof(*mr), elem);
725
726	rxe_put(mr_pd(mr));
727	ib_umem_release(mr->umem);
728
729	if (mr->ibmr.type != IB_MR_TYPE_DMA)
730		xa_destroy(&mr->page_list);
731}
732