1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2/*
3 * Copyright(c) 2016 Intel Corporation.
4 */
5
6#include <linux/slab.h>
7#include <linux/vmalloc.h>
8#include <rdma/ib_umem.h>
9#include <rdma/rdma_vt.h>
10#include "vt.h"
11#include "mr.h"
12#include "trace.h"
13
14/**
15 * rvt_driver_mr_init - Init MR resources per driver
16 * @rdi: rvt dev struct
17 *
18 * Do any intilization needed when a driver registers with rdmavt.
19 *
20 * Return: 0 on success or errno on failure
21 */
22int rvt_driver_mr_init(struct rvt_dev_info *rdi)
23{
24 unsigned int lkey_table_size = rdi->dparms.lkey_table_size;
25 unsigned lk_tab_size;
26 int i;
27
28 /*
29 * The top hfi1_lkey_table_size bits are used to index the
30 * table. The lower 8 bits can be owned by the user (copied from
31 * the LKEY). The remaining bits act as a generation number or tag.
32 */
33 if (!lkey_table_size)
34 return -EINVAL;
35
36 spin_lock_init(&rdi->lkey_table.lock);
37
38 /* ensure generation is at least 4 bits */
39 if (lkey_table_size > RVT_MAX_LKEY_TABLE_BITS) {
40 rvt_pr_warn(rdi, "lkey bits %u too large, reduced to %u\n",
41 lkey_table_size, RVT_MAX_LKEY_TABLE_BITS);
42 rdi->dparms.lkey_table_size = RVT_MAX_LKEY_TABLE_BITS;
43 lkey_table_size = rdi->dparms.lkey_table_size;
44 }
45 rdi->lkey_table.max = 1 << lkey_table_size;
46 rdi->lkey_table.shift = 32 - lkey_table_size;
47 lk_tab_size = rdi->lkey_table.max * sizeof(*rdi->lkey_table.table);
48 rdi->lkey_table.table = (struct rvt_mregion __rcu **)
49 vmalloc_node(size: lk_tab_size, node: rdi->dparms.node);
50 if (!rdi->lkey_table.table)
51 return -ENOMEM;
52
53 RCU_INIT_POINTER(rdi->dma_mr, NULL);
54 for (i = 0; i < rdi->lkey_table.max; i++)
55 RCU_INIT_POINTER(rdi->lkey_table.table[i], NULL);
56
57 rdi->dparms.props.max_mr = rdi->lkey_table.max;
58 return 0;
59}
60
61/**
62 * rvt_mr_exit - clean up MR
63 * @rdi: rvt dev structure
64 *
65 * called when drivers have unregistered or perhaps failed to register with us
66 */
67void rvt_mr_exit(struct rvt_dev_info *rdi)
68{
69 if (rdi->dma_mr)
70 rvt_pr_err(rdi, "DMA MR not null!\n");
71
72 vfree(addr: rdi->lkey_table.table);
73}
74
75static void rvt_deinit_mregion(struct rvt_mregion *mr)
76{
77 int i = mr->mapsz;
78
79 mr->mapsz = 0;
80 while (i)
81 kfree(objp: mr->map[--i]);
82 percpu_ref_exit(ref: &mr->refcount);
83}
84
85static void __rvt_mregion_complete(struct percpu_ref *ref)
86{
87 struct rvt_mregion *mr = container_of(ref, struct rvt_mregion,
88 refcount);
89
90 complete(&mr->comp);
91}
92
93static int rvt_init_mregion(struct rvt_mregion *mr, struct ib_pd *pd,
94 int count, unsigned int percpu_flags)
95{
96 int m, i = 0;
97 struct rvt_dev_info *dev = ib_to_rvt(ibdev: pd->device);
98
99 mr->mapsz = 0;
100 m = (count + RVT_SEGSZ - 1) / RVT_SEGSZ;
101 for (; i < m; i++) {
102 mr->map[i] = kzalloc_node(size: sizeof(*mr->map[0]), GFP_KERNEL,
103 node: dev->dparms.node);
104 if (!mr->map[i])
105 goto bail;
106 mr->mapsz++;
107 }
108 init_completion(x: &mr->comp);
109 /* count returning the ptr to user */
110 if (percpu_ref_init(ref: &mr->refcount, release: &__rvt_mregion_complete,
111 flags: percpu_flags, GFP_KERNEL))
112 goto bail;
113
114 atomic_set(v: &mr->lkey_invalid, i: 0);
115 mr->pd = pd;
116 mr->max_segs = count;
117 return 0;
118bail:
119 rvt_deinit_mregion(mr);
120 return -ENOMEM;
121}
122
123/**
124 * rvt_alloc_lkey - allocate an lkey
125 * @mr: memory region that this lkey protects
126 * @dma_region: 0->normal key, 1->restricted DMA key
127 *
128 * Returns 0 if successful, otherwise returns -errno.
129 *
130 * Increments mr reference count as required.
131 *
132 * Sets the lkey field mr for non-dma regions.
133 *
134 */
135static int rvt_alloc_lkey(struct rvt_mregion *mr, int dma_region)
136{
137 unsigned long flags;
138 u32 r;
139 u32 n;
140 int ret = 0;
141 struct rvt_dev_info *dev = ib_to_rvt(ibdev: mr->pd->device);
142 struct rvt_lkey_table *rkt = &dev->lkey_table;
143
144 rvt_get_mr(mr);
145 spin_lock_irqsave(&rkt->lock, flags);
146
147 /* special case for dma_mr lkey == 0 */
148 if (dma_region) {
149 struct rvt_mregion *tmr;
150
151 tmr = rcu_access_pointer(dev->dma_mr);
152 if (!tmr) {
153 mr->lkey_published = 1;
154 /* Insure published written first */
155 rcu_assign_pointer(dev->dma_mr, mr);
156 rvt_get_mr(mr);
157 }
158 goto success;
159 }
160
161 /* Find the next available LKEY */
162 r = rkt->next;
163 n = r;
164 for (;;) {
165 if (!rcu_access_pointer(rkt->table[r]))
166 break;
167 r = (r + 1) & (rkt->max - 1);
168 if (r == n)
169 goto bail;
170 }
171 rkt->next = (r + 1) & (rkt->max - 1);
172 /*
173 * Make sure lkey is never zero which is reserved to indicate an
174 * unrestricted LKEY.
175 */
176 rkt->gen++;
177 /*
178 * bits are capped to ensure enough bits for generation number
179 */
180 mr->lkey = (r << (32 - dev->dparms.lkey_table_size)) |
181 ((((1 << (24 - dev->dparms.lkey_table_size)) - 1) & rkt->gen)
182 << 8);
183 if (mr->lkey == 0) {
184 mr->lkey |= 1 << 8;
185 rkt->gen++;
186 }
187 mr->lkey_published = 1;
188 /* Insure published written first */
189 rcu_assign_pointer(rkt->table[r], mr);
190success:
191 spin_unlock_irqrestore(lock: &rkt->lock, flags);
192out:
193 return ret;
194bail:
195 rvt_put_mr(mr);
196 spin_unlock_irqrestore(lock: &rkt->lock, flags);
197 ret = -ENOMEM;
198 goto out;
199}
200
201/**
202 * rvt_free_lkey - free an lkey
203 * @mr: mr to free from tables
204 */
205static void rvt_free_lkey(struct rvt_mregion *mr)
206{
207 unsigned long flags;
208 u32 lkey = mr->lkey;
209 u32 r;
210 struct rvt_dev_info *dev = ib_to_rvt(ibdev: mr->pd->device);
211 struct rvt_lkey_table *rkt = &dev->lkey_table;
212 int freed = 0;
213
214 spin_lock_irqsave(&rkt->lock, flags);
215 if (!lkey) {
216 if (mr->lkey_published) {
217 mr->lkey_published = 0;
218 /* insure published is written before pointer */
219 rcu_assign_pointer(dev->dma_mr, NULL);
220 rvt_put_mr(mr);
221 }
222 } else {
223 if (!mr->lkey_published)
224 goto out;
225 r = lkey >> (32 - dev->dparms.lkey_table_size);
226 mr->lkey_published = 0;
227 /* insure published is written before pointer */
228 rcu_assign_pointer(rkt->table[r], NULL);
229 }
230 freed++;
231out:
232 spin_unlock_irqrestore(lock: &rkt->lock, flags);
233 if (freed)
234 percpu_ref_kill(ref: &mr->refcount);
235}
236
237static struct rvt_mr *__rvt_alloc_mr(int count, struct ib_pd *pd)
238{
239 struct rvt_mr *mr;
240 int rval = -ENOMEM;
241 int m;
242
243 /* Allocate struct plus pointers to first level page tables. */
244 m = (count + RVT_SEGSZ - 1) / RVT_SEGSZ;
245 mr = kzalloc(struct_size(mr, mr.map, m), GFP_KERNEL);
246 if (!mr)
247 goto bail;
248
249 rval = rvt_init_mregion(mr: &mr->mr, pd, count, percpu_flags: 0);
250 if (rval)
251 goto bail;
252 /*
253 * ib_reg_phys_mr() will initialize mr->ibmr except for
254 * lkey and rkey.
255 */
256 rval = rvt_alloc_lkey(mr: &mr->mr, dma_region: 0);
257 if (rval)
258 goto bail_mregion;
259 mr->ibmr.lkey = mr->mr.lkey;
260 mr->ibmr.rkey = mr->mr.lkey;
261done:
262 return mr;
263
264bail_mregion:
265 rvt_deinit_mregion(mr: &mr->mr);
266bail:
267 kfree(objp: mr);
268 mr = ERR_PTR(error: rval);
269 goto done;
270}
271
272static void __rvt_free_mr(struct rvt_mr *mr)
273{
274 rvt_free_lkey(mr: &mr->mr);
275 rvt_deinit_mregion(mr: &mr->mr);
276 kfree(objp: mr);
277}
278
279/**
280 * rvt_get_dma_mr - get a DMA memory region
281 * @pd: protection domain for this memory region
282 * @acc: access flags
283 *
284 * Return: the memory region on success, otherwise returns an errno.
285 */
286struct ib_mr *rvt_get_dma_mr(struct ib_pd *pd, int acc)
287{
288 struct rvt_mr *mr;
289 struct ib_mr *ret;
290 int rval;
291
292 if (ibpd_to_rvtpd(ibpd: pd)->user)
293 return ERR_PTR(error: -EPERM);
294
295 mr = kzalloc(size: sizeof(*mr), GFP_KERNEL);
296 if (!mr) {
297 ret = ERR_PTR(error: -ENOMEM);
298 goto bail;
299 }
300
301 rval = rvt_init_mregion(mr: &mr->mr, pd, count: 0, percpu_flags: 0);
302 if (rval) {
303 ret = ERR_PTR(error: rval);
304 goto bail;
305 }
306
307 rval = rvt_alloc_lkey(mr: &mr->mr, dma_region: 1);
308 if (rval) {
309 ret = ERR_PTR(error: rval);
310 goto bail_mregion;
311 }
312
313 mr->mr.access_flags = acc;
314 ret = &mr->ibmr;
315done:
316 return ret;
317
318bail_mregion:
319 rvt_deinit_mregion(mr: &mr->mr);
320bail:
321 kfree(objp: mr);
322 goto done;
323}
324
325/**
326 * rvt_reg_user_mr - register a userspace memory region
327 * @pd: protection domain for this memory region
328 * @start: starting userspace address
329 * @length: length of region to register
330 * @virt_addr: associated virtual address
331 * @mr_access_flags: access flags for this memory region
332 * @udata: unused by the driver
333 *
334 * Return: the memory region on success, otherwise returns an errno.
335 */
336struct ib_mr *rvt_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
337 u64 virt_addr, int mr_access_flags,
338 struct ib_udata *udata)
339{
340 struct rvt_mr *mr;
341 struct ib_umem *umem;
342 struct sg_page_iter sg_iter;
343 int n, m;
344 struct ib_mr *ret;
345
346 if (length == 0)
347 return ERR_PTR(error: -EINVAL);
348
349 umem = ib_umem_get(device: pd->device, addr: start, size: length, access: mr_access_flags);
350 if (IS_ERR(ptr: umem))
351 return (void *)umem;
352
353 n = ib_umem_num_pages(umem);
354
355 mr = __rvt_alloc_mr(count: n, pd);
356 if (IS_ERR(ptr: mr)) {
357 ret = (struct ib_mr *)mr;
358 goto bail_umem;
359 }
360
361 mr->mr.user_base = start;
362 mr->mr.iova = virt_addr;
363 mr->mr.length = length;
364 mr->mr.offset = ib_umem_offset(umem);
365 mr->mr.access_flags = mr_access_flags;
366 mr->umem = umem;
367
368 mr->mr.page_shift = PAGE_SHIFT;
369 m = 0;
370 n = 0;
371 for_each_sgtable_page (&umem->sgt_append.sgt, &sg_iter, 0) {
372 void *vaddr;
373
374 vaddr = page_address(sg_page_iter_page(&sg_iter));
375 if (!vaddr) {
376 ret = ERR_PTR(error: -EINVAL);
377 goto bail_inval;
378 }
379 mr->mr.map[m]->segs[n].vaddr = vaddr;
380 mr->mr.map[m]->segs[n].length = PAGE_SIZE;
381 trace_rvt_mr_user_seg(mr: &mr->mr, m, n, v: vaddr, PAGE_SIZE);
382 if (++n == RVT_SEGSZ) {
383 m++;
384 n = 0;
385 }
386 }
387 return &mr->ibmr;
388
389bail_inval:
390 __rvt_free_mr(mr);
391
392bail_umem:
393 ib_umem_release(umem);
394
395 return ret;
396}
397
398/**
399 * rvt_dereg_clean_qp_cb - callback from iterator
400 * @qp: the qp
401 * @v: the mregion (as u64)
402 *
403 * This routine fields the callback for all QPs and
404 * for QPs in the same PD as the MR will call the
405 * rvt_qp_mr_clean() to potentially cleanup references.
406 */
407static void rvt_dereg_clean_qp_cb(struct rvt_qp *qp, u64 v)
408{
409 struct rvt_mregion *mr = (struct rvt_mregion *)v;
410
411 /* skip PDs that are not ours */
412 if (mr->pd != qp->ibqp.pd)
413 return;
414 rvt_qp_mr_clean(qp, lkey: mr->lkey);
415}
416
417/**
418 * rvt_dereg_clean_qps - find QPs for reference cleanup
419 * @mr: the MR that is being deregistered
420 *
421 * This routine iterates RC QPs looking for references
422 * to the lkey noted in mr.
423 */
424static void rvt_dereg_clean_qps(struct rvt_mregion *mr)
425{
426 struct rvt_dev_info *rdi = ib_to_rvt(ibdev: mr->pd->device);
427
428 rvt_qp_iter(rdi, v: (u64)mr, cb: rvt_dereg_clean_qp_cb);
429}
430
431/**
432 * rvt_check_refs - check references
433 * @mr: the megion
434 * @t: the caller identification
435 *
436 * This routine checks MRs holding a reference during
437 * when being de-registered.
438 *
439 * If the count is non-zero, the code calls a clean routine then
440 * waits for the timeout for the count to zero.
441 */
442static int rvt_check_refs(struct rvt_mregion *mr, const char *t)
443{
444 unsigned long timeout;
445 struct rvt_dev_info *rdi = ib_to_rvt(ibdev: mr->pd->device);
446
447 if (mr->lkey) {
448 /* avoid dma mr */
449 rvt_dereg_clean_qps(mr);
450 /* @mr was indexed on rcu protected @lkey_table */
451 synchronize_rcu();
452 }
453
454 timeout = wait_for_completion_timeout(x: &mr->comp, timeout: 5 * HZ);
455 if (!timeout) {
456 rvt_pr_err(rdi,
457 "%s timeout mr %p pd %p lkey %x refcount %ld\n",
458 t, mr, mr->pd, mr->lkey,
459 atomic_long_read(&mr->refcount.data->count));
460 rvt_get_mr(mr);
461 return -EBUSY;
462 }
463 return 0;
464}
465
466/**
467 * rvt_mr_has_lkey - is MR
468 * @mr: the mregion
469 * @lkey: the lkey
470 */
471bool rvt_mr_has_lkey(struct rvt_mregion *mr, u32 lkey)
472{
473 return mr && lkey == mr->lkey;
474}
475
476/**
477 * rvt_ss_has_lkey - is mr in sge tests
478 * @ss: the sge state
479 * @lkey: the lkey
480 *
481 * This code tests for an MR in the indicated
482 * sge state.
483 */
484bool rvt_ss_has_lkey(struct rvt_sge_state *ss, u32 lkey)
485{
486 int i;
487 bool rval = false;
488
489 if (!ss->num_sge)
490 return rval;
491 /* first one */
492 rval = rvt_mr_has_lkey(mr: ss->sge.mr, lkey);
493 /* any others */
494 for (i = 0; !rval && i < ss->num_sge - 1; i++)
495 rval = rvt_mr_has_lkey(mr: ss->sg_list[i].mr, lkey);
496 return rval;
497}
498
499/**
500 * rvt_dereg_mr - unregister and free a memory region
501 * @ibmr: the memory region to free
502 * @udata: unused by the driver
503 *
504 * Note that this is called to free MRs created by rvt_get_dma_mr()
505 * or rvt_reg_user_mr().
506 *
507 * Returns 0 on success.
508 */
509int rvt_dereg_mr(struct ib_mr *ibmr, struct ib_udata *udata)
510{
511 struct rvt_mr *mr = to_imr(ibmr);
512 int ret;
513
514 rvt_free_lkey(mr: &mr->mr);
515
516 rvt_put_mr(mr: &mr->mr); /* will set completion if last */
517 ret = rvt_check_refs(mr: &mr->mr, t: __func__);
518 if (ret)
519 goto out;
520 rvt_deinit_mregion(mr: &mr->mr);
521 ib_umem_release(umem: mr->umem);
522 kfree(objp: mr);
523out:
524 return ret;
525}
526
527/**
528 * rvt_alloc_mr - Allocate a memory region usable with the
529 * @pd: protection domain for this memory region
530 * @mr_type: mem region type
531 * @max_num_sg: Max number of segments allowed
532 *
533 * Return: the memory region on success, otherwise return an errno.
534 */
535struct ib_mr *rvt_alloc_mr(struct ib_pd *pd, enum ib_mr_type mr_type,
536 u32 max_num_sg)
537{
538 struct rvt_mr *mr;
539
540 if (mr_type != IB_MR_TYPE_MEM_REG)
541 return ERR_PTR(error: -EINVAL);
542
543 mr = __rvt_alloc_mr(count: max_num_sg, pd);
544 if (IS_ERR(ptr: mr))
545 return (struct ib_mr *)mr;
546
547 return &mr->ibmr;
548}
549
550/**
551 * rvt_set_page - page assignment function called by ib_sg_to_pages
552 * @ibmr: memory region
553 * @addr: dma address of mapped page
554 *
555 * Return: 0 on success
556 */
557static int rvt_set_page(struct ib_mr *ibmr, u64 addr)
558{
559 struct rvt_mr *mr = to_imr(ibmr);
560 u32 ps = 1 << mr->mr.page_shift;
561 u32 mapped_segs = mr->mr.length >> mr->mr.page_shift;
562 int m, n;
563
564 if (unlikely(mapped_segs == mr->mr.max_segs))
565 return -ENOMEM;
566
567 m = mapped_segs / RVT_SEGSZ;
568 n = mapped_segs % RVT_SEGSZ;
569 mr->mr.map[m]->segs[n].vaddr = (void *)addr;
570 mr->mr.map[m]->segs[n].length = ps;
571 mr->mr.length += ps;
572 trace_rvt_mr_page_seg(mr: &mr->mr, m, n, v: (void *)addr, len: ps);
573
574 return 0;
575}
576
577/**
578 * rvt_map_mr_sg - map sg list and set it the memory region
579 * @ibmr: memory region
580 * @sg: dma mapped scatterlist
581 * @sg_nents: number of entries in sg
582 * @sg_offset: offset in bytes into sg
583 *
584 * Overwrite rvt_mr length with mr length calculated by ib_sg_to_pages.
585 *
586 * Return: number of sg elements mapped to the memory region
587 */
588int rvt_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg,
589 int sg_nents, unsigned int *sg_offset)
590{
591 struct rvt_mr *mr = to_imr(ibmr);
592 int ret;
593
594 mr->mr.length = 0;
595 mr->mr.page_shift = PAGE_SHIFT;
596 ret = ib_sg_to_pages(mr: ibmr, sgl: sg, sg_nents, sg_offset, set_page: rvt_set_page);
597 mr->mr.user_base = ibmr->iova;
598 mr->mr.iova = ibmr->iova;
599 mr->mr.offset = ibmr->iova - (u64)mr->mr.map[0]->segs[0].vaddr;
600 mr->mr.length = (size_t)ibmr->length;
601 trace_rvt_map_mr_sg(ibmr, sg_nents, sg_offset);
602 return ret;
603}
604
605/**
606 * rvt_fast_reg_mr - fast register physical MR
607 * @qp: the queue pair where the work request comes from
608 * @ibmr: the memory region to be registered
609 * @key: updated key for this memory region
610 * @access: access flags for this memory region
611 *
612 * Returns 0 on success.
613 */
614int rvt_fast_reg_mr(struct rvt_qp *qp, struct ib_mr *ibmr, u32 key,
615 int access)
616{
617 struct rvt_mr *mr = to_imr(ibmr);
618
619 if (qp->ibqp.pd != mr->mr.pd)
620 return -EACCES;
621
622 /* not applicable to dma MR or user MR */
623 if (!mr->mr.lkey || mr->umem)
624 return -EINVAL;
625
626 if ((key & 0xFFFFFF00) != (mr->mr.lkey & 0xFFFFFF00))
627 return -EINVAL;
628
629 ibmr->lkey = key;
630 ibmr->rkey = key;
631 mr->mr.lkey = key;
632 mr->mr.access_flags = access;
633 mr->mr.iova = ibmr->iova;
634 atomic_set(v: &mr->mr.lkey_invalid, i: 0);
635
636 return 0;
637}
638EXPORT_SYMBOL(rvt_fast_reg_mr);
639
640/**
641 * rvt_invalidate_rkey - invalidate an MR rkey
642 * @qp: queue pair associated with the invalidate op
643 * @rkey: rkey to invalidate
644 *
645 * Returns 0 on success.
646 */
647int rvt_invalidate_rkey(struct rvt_qp *qp, u32 rkey)
648{
649 struct rvt_dev_info *dev = ib_to_rvt(ibdev: qp->ibqp.device);
650 struct rvt_lkey_table *rkt = &dev->lkey_table;
651 struct rvt_mregion *mr;
652
653 if (rkey == 0)
654 return -EINVAL;
655
656 rcu_read_lock();
657 mr = rcu_dereference(
658 rkt->table[(rkey >> (32 - dev->dparms.lkey_table_size))]);
659 if (unlikely(!mr || mr->lkey != rkey || qp->ibqp.pd != mr->pd))
660 goto bail;
661
662 atomic_set(v: &mr->lkey_invalid, i: 1);
663 rcu_read_unlock();
664 return 0;
665
666bail:
667 rcu_read_unlock();
668 return -EINVAL;
669}
670EXPORT_SYMBOL(rvt_invalidate_rkey);
671
672/**
673 * rvt_sge_adjacent - is isge compressible
674 * @last_sge: last outgoing SGE written
675 * @sge: SGE to check
676 *
677 * If adjacent will update last_sge to add length.
678 *
679 * Return: true if isge is adjacent to last sge
680 */
681static inline bool rvt_sge_adjacent(struct rvt_sge *last_sge,
682 struct ib_sge *sge)
683{
684 if (last_sge && sge->lkey == last_sge->mr->lkey &&
685 ((uint64_t)(last_sge->vaddr + last_sge->length) == sge->addr)) {
686 if (sge->lkey) {
687 if (unlikely((sge->addr - last_sge->mr->user_base +
688 sge->length > last_sge->mr->length)))
689 return false; /* overrun, caller will catch */
690 } else {
691 last_sge->length += sge->length;
692 }
693 last_sge->sge_length += sge->length;
694 trace_rvt_sge_adjacent(sge: last_sge, isge: sge);
695 return true;
696 }
697 return false;
698}
699
700/**
701 * rvt_lkey_ok - check IB SGE for validity and initialize
702 * @rkt: table containing lkey to check SGE against
703 * @pd: protection domain
704 * @isge: outgoing internal SGE
705 * @last_sge: last outgoing SGE written
706 * @sge: SGE to check
707 * @acc: access flags
708 *
709 * Check the IB SGE for validity and initialize our internal version
710 * of it.
711 *
712 * Increments the reference count when a new sge is stored.
713 *
714 * Return: 0 if compressed, 1 if added , otherwise returns -errno.
715 */
716int rvt_lkey_ok(struct rvt_lkey_table *rkt, struct rvt_pd *pd,
717 struct rvt_sge *isge, struct rvt_sge *last_sge,
718 struct ib_sge *sge, int acc)
719{
720 struct rvt_mregion *mr;
721 unsigned n, m;
722 size_t off;
723
724 /*
725 * We use LKEY == zero for kernel virtual addresses
726 * (see rvt_get_dma_mr()).
727 */
728 if (sge->lkey == 0) {
729 struct rvt_dev_info *dev = ib_to_rvt(ibdev: pd->ibpd.device);
730
731 if (pd->user)
732 return -EINVAL;
733 if (rvt_sge_adjacent(last_sge, sge))
734 return 0;
735 rcu_read_lock();
736 mr = rcu_dereference(dev->dma_mr);
737 if (!mr)
738 goto bail;
739 rvt_get_mr(mr);
740 rcu_read_unlock();
741
742 isge->mr = mr;
743 isge->vaddr = (void *)sge->addr;
744 isge->length = sge->length;
745 isge->sge_length = sge->length;
746 isge->m = 0;
747 isge->n = 0;
748 goto ok;
749 }
750 if (rvt_sge_adjacent(last_sge, sge))
751 return 0;
752 rcu_read_lock();
753 mr = rcu_dereference(rkt->table[sge->lkey >> rkt->shift]);
754 if (!mr)
755 goto bail;
756 rvt_get_mr(mr);
757 if (!READ_ONCE(mr->lkey_published))
758 goto bail_unref;
759
760 if (unlikely(atomic_read(&mr->lkey_invalid) ||
761 mr->lkey != sge->lkey || mr->pd != &pd->ibpd))
762 goto bail_unref;
763
764 off = sge->addr - mr->user_base;
765 if (unlikely(sge->addr < mr->user_base ||
766 off + sge->length > mr->length ||
767 (mr->access_flags & acc) != acc))
768 goto bail_unref;
769 rcu_read_unlock();
770
771 off += mr->offset;
772 if (mr->page_shift) {
773 /*
774 * page sizes are uniform power of 2 so no loop is necessary
775 * entries_spanned_by_off is the number of times the loop below
776 * would have executed.
777 */
778 size_t entries_spanned_by_off;
779
780 entries_spanned_by_off = off >> mr->page_shift;
781 off -= (entries_spanned_by_off << mr->page_shift);
782 m = entries_spanned_by_off / RVT_SEGSZ;
783 n = entries_spanned_by_off % RVT_SEGSZ;
784 } else {
785 m = 0;
786 n = 0;
787 while (off >= mr->map[m]->segs[n].length) {
788 off -= mr->map[m]->segs[n].length;
789 n++;
790 if (n >= RVT_SEGSZ) {
791 m++;
792 n = 0;
793 }
794 }
795 }
796 isge->mr = mr;
797 isge->vaddr = mr->map[m]->segs[n].vaddr + off;
798 isge->length = mr->map[m]->segs[n].length - off;
799 isge->sge_length = sge->length;
800 isge->m = m;
801 isge->n = n;
802ok:
803 trace_rvt_sge_new(sge: isge, isge: sge);
804 return 1;
805bail_unref:
806 rvt_put_mr(mr);
807bail:
808 rcu_read_unlock();
809 return -EINVAL;
810}
811EXPORT_SYMBOL(rvt_lkey_ok);
812
813/**
814 * rvt_rkey_ok - check the IB virtual address, length, and RKEY
815 * @qp: qp for validation
816 * @sge: SGE state
817 * @len: length of data
818 * @vaddr: virtual address to place data
819 * @rkey: rkey to check
820 * @acc: access flags
821 *
822 * Return: 1 if successful, otherwise 0.
823 *
824 * increments the reference count upon success
825 */
826int rvt_rkey_ok(struct rvt_qp *qp, struct rvt_sge *sge,
827 u32 len, u64 vaddr, u32 rkey, int acc)
828{
829 struct rvt_dev_info *dev = ib_to_rvt(ibdev: qp->ibqp.device);
830 struct rvt_lkey_table *rkt = &dev->lkey_table;
831 struct rvt_mregion *mr;
832 unsigned n, m;
833 size_t off;
834
835 /*
836 * We use RKEY == zero for kernel virtual addresses
837 * (see rvt_get_dma_mr()).
838 */
839 rcu_read_lock();
840 if (rkey == 0) {
841 struct rvt_pd *pd = ibpd_to_rvtpd(ibpd: qp->ibqp.pd);
842 struct rvt_dev_info *rdi = ib_to_rvt(ibdev: pd->ibpd.device);
843
844 if (pd->user)
845 goto bail;
846 mr = rcu_dereference(rdi->dma_mr);
847 if (!mr)
848 goto bail;
849 rvt_get_mr(mr);
850 rcu_read_unlock();
851
852 sge->mr = mr;
853 sge->vaddr = (void *)vaddr;
854 sge->length = len;
855 sge->sge_length = len;
856 sge->m = 0;
857 sge->n = 0;
858 goto ok;
859 }
860
861 mr = rcu_dereference(rkt->table[rkey >> rkt->shift]);
862 if (!mr)
863 goto bail;
864 rvt_get_mr(mr);
865 /* insure mr read is before test */
866 if (!READ_ONCE(mr->lkey_published))
867 goto bail_unref;
868 if (unlikely(atomic_read(&mr->lkey_invalid) ||
869 mr->lkey != rkey || qp->ibqp.pd != mr->pd))
870 goto bail_unref;
871
872 off = vaddr - mr->iova;
873 if (unlikely(vaddr < mr->iova || off + len > mr->length ||
874 (mr->access_flags & acc) == 0))
875 goto bail_unref;
876 rcu_read_unlock();
877
878 off += mr->offset;
879 if (mr->page_shift) {
880 /*
881 * page sizes are uniform power of 2 so no loop is necessary
882 * entries_spanned_by_off is the number of times the loop below
883 * would have executed.
884 */
885 size_t entries_spanned_by_off;
886
887 entries_spanned_by_off = off >> mr->page_shift;
888 off -= (entries_spanned_by_off << mr->page_shift);
889 m = entries_spanned_by_off / RVT_SEGSZ;
890 n = entries_spanned_by_off % RVT_SEGSZ;
891 } else {
892 m = 0;
893 n = 0;
894 while (off >= mr->map[m]->segs[n].length) {
895 off -= mr->map[m]->segs[n].length;
896 n++;
897 if (n >= RVT_SEGSZ) {
898 m++;
899 n = 0;
900 }
901 }
902 }
903 sge->mr = mr;
904 sge->vaddr = mr->map[m]->segs[n].vaddr + off;
905 sge->length = mr->map[m]->segs[n].length - off;
906 sge->sge_length = len;
907 sge->m = m;
908 sge->n = n;
909ok:
910 return 1;
911bail_unref:
912 rvt_put_mr(mr);
913bail:
914 rcu_read_unlock();
915 return 0;
916}
917EXPORT_SYMBOL(rvt_rkey_ok);
918

source code of linux/drivers/infiniband/sw/rdmavt/mr.c