1 /*
2 * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33 #include <rdma/ib_umem_odp.h>
34 #include <linux/kernel.h>
35 #include <linux/dma-buf.h>
36 #include <linux/dma-resv.h>
37
38 #include "mlx5_ib.h"
39 #include "cmd.h"
40 #include "umr.h"
41 #include "qp.h"
42
43 #include <linux/mlx5/eq.h>
44
45 /* Contains the details of a pagefault. */
46 struct mlx5_pagefault {
47 u32 bytes_committed;
48 u64 token;
49 u8 event_subtype;
50 u8 type;
51 union {
52 /* Initiator or send message responder pagefault details. */
53 struct {
54 /* Received packet size, only valid for responders. */
55 u32 packet_size;
56 /*
57 * Number of resource holding WQE, depends on type.
58 */
59 u32 wq_num;
60 /*
61 * WQE index. Refers to either the send queue or
62 * receive queue, according to event_subtype.
63 */
64 u16 wqe_index;
65 } wqe;
66 /* RDMA responder pagefault details */
67 struct {
68 u32 r_key;
69 /*
70 * Received packet size, minimal size page fault
71 * resolution required for forward progress.
72 */
73 u32 packet_size;
74 u32 rdma_op_len;
75 u64 rdma_va;
76 } rdma;
77 struct {
78 u64 va;
79 u32 mkey;
80 u32 fault_byte_count;
81 u32 prefetch_before_byte_count;
82 u32 prefetch_after_byte_count;
83 u8 flags;
84 } memory;
85 };
86
87 struct mlx5_ib_pf_eq *eq;
88 struct work_struct work;
89 };
90
91 #define MAX_PREFETCH_LEN (4*1024*1024U)
92
93 /* Timeout in ms to wait for an active mmu notifier to complete when handling
94 * a pagefault. */
95 #define MMU_NOTIFIER_TIMEOUT 1000
96
97 #define MLX5_IMR_MTT_BITS (30 - PAGE_SHIFT)
98 #define MLX5_IMR_MTT_SHIFT (MLX5_IMR_MTT_BITS + PAGE_SHIFT)
99 #define MLX5_IMR_MTT_ENTRIES BIT_ULL(MLX5_IMR_MTT_BITS)
100 #define MLX5_IMR_MTT_SIZE BIT_ULL(MLX5_IMR_MTT_SHIFT)
101 #define MLX5_IMR_MTT_MASK (~(MLX5_IMR_MTT_SIZE - 1))
102
103 #define MLX5_KSM_PAGE_SHIFT MLX5_IMR_MTT_SHIFT
104
105 static u64 mlx5_imr_ksm_entries;
106
populate_klm(struct mlx5_klm * pklm,size_t idx,size_t nentries,struct mlx5_ib_mr * imr,int flags)107 static void populate_klm(struct mlx5_klm *pklm, size_t idx, size_t nentries,
108 struct mlx5_ib_mr *imr, int flags)
109 {
110 struct mlx5_core_dev *dev = mr_to_mdev(imr)->mdev;
111 struct mlx5_klm *end = pklm + nentries;
112 int step = MLX5_CAP_ODP(dev, mem_page_fault) ? MLX5_IMR_MTT_SIZE : 0;
113 __be32 key = MLX5_CAP_ODP(dev, mem_page_fault) ?
114 cpu_to_be32(imr->null_mmkey.key) :
115 mr_to_mdev(imr)->mkeys.null_mkey;
116 u64 va =
117 MLX5_CAP_ODP(dev, mem_page_fault) ? idx * MLX5_IMR_MTT_SIZE : 0;
118
119 if (flags & MLX5_IB_UPD_XLT_ZAP) {
120 for (; pklm != end; pklm++, idx++, va += step) {
121 pklm->bcount = cpu_to_be32(MLX5_IMR_MTT_SIZE);
122 pklm->key = key;
123 pklm->va = cpu_to_be64(va);
124 }
125 return;
126 }
127
128 /*
129 * The locking here is pretty subtle. Ideally the implicit_children
130 * xarray would be protected by the umem_mutex, however that is not
131 * possible. Instead this uses a weaker update-then-lock pattern:
132 *
133 * xa_store()
134 * mutex_lock(umem_mutex)
135 * mlx5r_umr_update_xlt()
136 * mutex_unlock(umem_mutex)
137 * destroy lkey
138 *
139 * ie any change the xarray must be followed by the locked update_xlt
140 * before destroying.
141 *
142 * The umem_mutex provides the acquire/release semantic needed to make
143 * the xa_store() visible to a racing thread.
144 */
145 lockdep_assert_held(&to_ib_umem_odp(imr->umem)->umem_mutex);
146
147 for (; pklm != end; pklm++, idx++, va += step) {
148 struct mlx5_ib_mr *mtt = xa_load(&imr->implicit_children, idx);
149
150 pklm->bcount = cpu_to_be32(MLX5_IMR_MTT_SIZE);
151 if (mtt) {
152 pklm->key = cpu_to_be32(mtt->ibmr.lkey);
153 pklm->va = cpu_to_be64(idx * MLX5_IMR_MTT_SIZE);
154 } else {
155 pklm->key = key;
156 pklm->va = cpu_to_be64(va);
157 }
158 }
159 }
160
umem_dma_to_mtt(dma_addr_t umem_dma)161 static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
162 {
163 u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
164
165 if (umem_dma & ODP_READ_ALLOWED_BIT)
166 mtt_entry |= MLX5_IB_MTT_READ;
167 if (umem_dma & ODP_WRITE_ALLOWED_BIT)
168 mtt_entry |= MLX5_IB_MTT_WRITE;
169
170 return mtt_entry;
171 }
172
populate_mtt(__be64 * pas,size_t idx,size_t nentries,struct mlx5_ib_mr * mr,int flags)173 static void populate_mtt(__be64 *pas, size_t idx, size_t nentries,
174 struct mlx5_ib_mr *mr, int flags)
175 {
176 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
177 dma_addr_t pa;
178 size_t i;
179
180 if (flags & MLX5_IB_UPD_XLT_ZAP)
181 return;
182
183 for (i = 0; i < nentries; i++) {
184 pa = odp->dma_list[idx + i];
185 pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
186 }
187 }
188
mlx5_odp_populate_xlt(void * xlt,size_t idx,size_t nentries,struct mlx5_ib_mr * mr,int flags)189 void mlx5_odp_populate_xlt(void *xlt, size_t idx, size_t nentries,
190 struct mlx5_ib_mr *mr, int flags)
191 {
192 if (flags & MLX5_IB_UPD_XLT_INDIRECT) {
193 populate_klm(xlt, idx, nentries, mr, flags);
194 } else {
195 populate_mtt(xlt, idx, nentries, mr, flags);
196 }
197 }
198
199 /*
200 * This must be called after the mr has been removed from implicit_children.
201 * NOTE: The MR does not necessarily have to be
202 * empty here, parallel page faults could have raced with the free process and
203 * added pages to it.
204 */
free_implicit_child_mr_work(struct work_struct * work)205 static void free_implicit_child_mr_work(struct work_struct *work)
206 {
207 struct mlx5_ib_mr *mr =
208 container_of(work, struct mlx5_ib_mr, odp_destroy.work);
209 struct mlx5_ib_mr *imr = mr->parent;
210 struct ib_umem_odp *odp_imr = to_ib_umem_odp(imr->umem);
211 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
212
213 mlx5r_deref_wait_odp_mkey(&mr->mmkey);
214
215 mutex_lock(&odp_imr->umem_mutex);
216 mlx5r_umr_update_xlt(mr->parent,
217 ib_umem_start(odp) >> MLX5_IMR_MTT_SHIFT, 1, 0,
218 MLX5_IB_UPD_XLT_INDIRECT | MLX5_IB_UPD_XLT_ATOMIC);
219 mutex_unlock(&odp_imr->umem_mutex);
220 mlx5_ib_dereg_mr(&mr->ibmr, NULL);
221
222 mlx5r_deref_odp_mkey(&imr->mmkey);
223 }
224
destroy_unused_implicit_child_mr(struct mlx5_ib_mr * mr)225 static void destroy_unused_implicit_child_mr(struct mlx5_ib_mr *mr)
226 {
227 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
228 unsigned long idx = ib_umem_start(odp) >> MLX5_IMR_MTT_SHIFT;
229 struct mlx5_ib_mr *imr = mr->parent;
230
231 if (!refcount_inc_not_zero(&imr->mmkey.usecount))
232 return;
233
234 xa_erase(&imr->implicit_children, idx);
235 if (MLX5_CAP_ODP(mr_to_mdev(mr)->mdev, mem_page_fault))
236 xa_erase(&mr_to_mdev(mr)->odp_mkeys,
237 mlx5_base_mkey(mr->mmkey.key));
238
239 /* Freeing a MR is a sleeping operation, so bounce to a work queue */
240 INIT_WORK(&mr->odp_destroy.work, free_implicit_child_mr_work);
241 queue_work(system_unbound_wq, &mr->odp_destroy.work);
242 }
243
mlx5_ib_invalidate_range(struct mmu_interval_notifier * mni,const struct mmu_notifier_range * range,unsigned long cur_seq)244 static bool mlx5_ib_invalidate_range(struct mmu_interval_notifier *mni,
245 const struct mmu_notifier_range *range,
246 unsigned long cur_seq)
247 {
248 struct ib_umem_odp *umem_odp =
249 container_of(mni, struct ib_umem_odp, notifier);
250 struct mlx5_ib_mr *mr;
251 const u64 umr_block_mask = MLX5_UMR_MTT_NUM_ENTRIES_ALIGNMENT - 1;
252 u64 idx = 0, blk_start_idx = 0;
253 u64 invalidations = 0;
254 unsigned long start;
255 unsigned long end;
256 int in_block = 0;
257 u64 addr;
258
259 if (!mmu_notifier_range_blockable(range))
260 return false;
261
262 mutex_lock(&umem_odp->umem_mutex);
263 mmu_interval_set_seq(mni, cur_seq);
264 /*
265 * If npages is zero then umem_odp->private may not be setup yet. This
266 * does not complete until after the first page is mapped for DMA.
267 */
268 if (!umem_odp->npages)
269 goto out;
270 mr = umem_odp->private;
271
272 start = max_t(u64, ib_umem_start(umem_odp), range->start);
273 end = min_t(u64, ib_umem_end(umem_odp), range->end);
274
275 /*
276 * Iteration one - zap the HW's MTTs. The notifiers_count ensures that
277 * while we are doing the invalidation, no page fault will attempt to
278 * overwrite the same MTTs. Concurent invalidations might race us,
279 * but they will write 0s as well, so no difference in the end result.
280 */
281 for (addr = start; addr < end; addr += BIT(umem_odp->page_shift)) {
282 idx = (addr - ib_umem_start(umem_odp)) >> umem_odp->page_shift;
283 /*
284 * Strive to write the MTTs in chunks, but avoid overwriting
285 * non-existing MTTs. The huristic here can be improved to
286 * estimate the cost of another UMR vs. the cost of bigger
287 * UMR.
288 */
289 if (umem_odp->dma_list[idx] &
290 (ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT)) {
291 if (!in_block) {
292 blk_start_idx = idx;
293 in_block = 1;
294 }
295
296 /* Count page invalidations */
297 invalidations += idx - blk_start_idx + 1;
298 } else {
299 u64 umr_offset = idx & umr_block_mask;
300
301 if (in_block && umr_offset == 0) {
302 mlx5r_umr_update_xlt(mr, blk_start_idx,
303 idx - blk_start_idx, 0,
304 MLX5_IB_UPD_XLT_ZAP |
305 MLX5_IB_UPD_XLT_ATOMIC);
306 in_block = 0;
307 }
308 }
309 }
310 if (in_block)
311 mlx5r_umr_update_xlt(mr, blk_start_idx,
312 idx - blk_start_idx + 1, 0,
313 MLX5_IB_UPD_XLT_ZAP |
314 MLX5_IB_UPD_XLT_ATOMIC);
315
316 mlx5_update_odp_stats(mr, invalidations, invalidations);
317
318 /*
319 * We are now sure that the device will not access the
320 * memory. We can safely unmap it, and mark it as dirty if
321 * needed.
322 */
323
324 ib_umem_odp_unmap_dma_pages(umem_odp, start, end);
325
326 if (unlikely(!umem_odp->npages && mr->parent))
327 destroy_unused_implicit_child_mr(mr);
328 out:
329 mutex_unlock(&umem_odp->umem_mutex);
330 return true;
331 }
332
333 const struct mmu_interval_notifier_ops mlx5_mn_ops = {
334 .invalidate = mlx5_ib_invalidate_range,
335 };
336
internal_fill_odp_caps(struct mlx5_ib_dev * dev)337 static void internal_fill_odp_caps(struct mlx5_ib_dev *dev)
338 {
339 struct ib_odp_caps *caps = &dev->odp_caps;
340
341 memset(caps, 0, sizeof(*caps));
342
343 if (!MLX5_CAP_GEN(dev->mdev, pg) || !mlx5r_umr_can_load_pas(dev, 0))
344 return;
345
346 caps->general_caps = IB_ODP_SUPPORT;
347
348 if (MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset))
349 dev->odp_max_size = U64_MAX;
350 else
351 dev->odp_max_size = BIT_ULL(MLX5_MAX_UMR_SHIFT + PAGE_SHIFT);
352
353 if (MLX5_CAP_ODP_SCHEME(dev->mdev, ud_odp_caps.send))
354 caps->per_transport_caps.ud_odp_caps |= IB_ODP_SUPPORT_SEND;
355
356 if (MLX5_CAP_ODP_SCHEME(dev->mdev, ud_odp_caps.srq_receive))
357 caps->per_transport_caps.ud_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
358
359 if (MLX5_CAP_ODP_SCHEME(dev->mdev, rc_odp_caps.send))
360 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_SEND;
361
362 if (MLX5_CAP_ODP_SCHEME(dev->mdev, rc_odp_caps.receive))
363 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_RECV;
364
365 if (MLX5_CAP_ODP_SCHEME(dev->mdev, rc_odp_caps.write))
366 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_WRITE;
367
368 if (MLX5_CAP_ODP_SCHEME(dev->mdev, rc_odp_caps.read))
369 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_READ;
370
371 if (MLX5_CAP_ODP_SCHEME(dev->mdev, rc_odp_caps.atomic))
372 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_ATOMIC;
373
374 if (MLX5_CAP_ODP_SCHEME(dev->mdev, rc_odp_caps.srq_receive))
375 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
376
377 if (MLX5_CAP_ODP_SCHEME(dev->mdev, xrc_odp_caps.send))
378 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_SEND;
379
380 if (MLX5_CAP_ODP_SCHEME(dev->mdev, xrc_odp_caps.receive))
381 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_RECV;
382
383 if (MLX5_CAP_ODP_SCHEME(dev->mdev, xrc_odp_caps.write))
384 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_WRITE;
385
386 if (MLX5_CAP_ODP_SCHEME(dev->mdev, xrc_odp_caps.read))
387 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_READ;
388
389 if (MLX5_CAP_ODP_SCHEME(dev->mdev, xrc_odp_caps.atomic))
390 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_ATOMIC;
391
392 if (MLX5_CAP_ODP_SCHEME(dev->mdev, xrc_odp_caps.srq_receive))
393 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
394
395 if (MLX5_CAP_GEN(dev->mdev, fixed_buffer_size) &&
396 MLX5_CAP_GEN(dev->mdev, null_mkey) &&
397 MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset) &&
398 !MLX5_CAP_GEN(dev->mdev, umr_indirect_mkey_disabled))
399 caps->general_caps |= IB_ODP_SUPPORT_IMPLICIT;
400 }
401
mlx5_ib_page_fault_resume(struct mlx5_ib_dev * dev,struct mlx5_pagefault * pfault,int error)402 static void mlx5_ib_page_fault_resume(struct mlx5_ib_dev *dev,
403 struct mlx5_pagefault *pfault,
404 int error)
405 {
406 int wq_num = pfault->event_subtype == MLX5_PFAULT_SUBTYPE_WQE ?
407 pfault->wqe.wq_num : pfault->token;
408 u32 in[MLX5_ST_SZ_DW(page_fault_resume_in)] = {};
409 void *info;
410 int err;
411
412 MLX5_SET(page_fault_resume_in, in, opcode, MLX5_CMD_OP_PAGE_FAULT_RESUME);
413
414 if (pfault->event_subtype == MLX5_PFAULT_SUBTYPE_MEMORY) {
415 info = MLX5_ADDR_OF(page_fault_resume_in, in,
416 page_fault_info.mem_page_fault_info);
417 MLX5_SET(mem_page_fault_info, info, fault_token_31_0,
418 pfault->token & 0xffffffff);
419 MLX5_SET(mem_page_fault_info, info, fault_token_47_32,
420 (pfault->token >> 32) & 0xffff);
421 MLX5_SET(mem_page_fault_info, info, error, !!error);
422 } else {
423 info = MLX5_ADDR_OF(page_fault_resume_in, in,
424 page_fault_info.trans_page_fault_info);
425 MLX5_SET(trans_page_fault_info, info, page_fault_type,
426 pfault->type);
427 MLX5_SET(trans_page_fault_info, info, fault_token,
428 pfault->token);
429 MLX5_SET(trans_page_fault_info, info, wq_number, wq_num);
430 MLX5_SET(trans_page_fault_info, info, error, !!error);
431 }
432
433 err = mlx5_cmd_exec_in(dev->mdev, page_fault_resume, in);
434 if (err)
435 mlx5_ib_err(dev, "Failed to resolve the page fault on WQ 0x%x err %d\n",
436 wq_num, err);
437 }
438
implicit_get_child_mr(struct mlx5_ib_mr * imr,unsigned long idx)439 static struct mlx5_ib_mr *implicit_get_child_mr(struct mlx5_ib_mr *imr,
440 unsigned long idx)
441 {
442 struct mlx5_ib_dev *dev = mr_to_mdev(imr);
443 struct ib_umem_odp *odp;
444 struct mlx5_ib_mr *mr;
445 struct mlx5_ib_mr *ret;
446 int err;
447
448 odp = ib_umem_odp_alloc_child(to_ib_umem_odp(imr->umem),
449 idx * MLX5_IMR_MTT_SIZE,
450 MLX5_IMR_MTT_SIZE, &mlx5_mn_ops);
451 if (IS_ERR(odp))
452 return ERR_CAST(odp);
453
454 mr = mlx5_mr_cache_alloc(dev, imr->access_flags,
455 MLX5_MKC_ACCESS_MODE_MTT,
456 MLX5_IMR_MTT_ENTRIES);
457 if (IS_ERR(mr)) {
458 ib_umem_odp_release(odp);
459 return mr;
460 }
461
462 mr->access_flags = imr->access_flags;
463 mr->ibmr.pd = imr->ibmr.pd;
464 mr->ibmr.device = &mr_to_mdev(imr)->ib_dev;
465 mr->umem = &odp->umem;
466 mr->ibmr.lkey = mr->mmkey.key;
467 mr->ibmr.rkey = mr->mmkey.key;
468 mr->ibmr.iova = idx * MLX5_IMR_MTT_SIZE;
469 mr->parent = imr;
470 odp->private = mr;
471
472 /*
473 * First refcount is owned by the xarray and second refconut
474 * is returned to the caller.
475 */
476 refcount_set(&mr->mmkey.usecount, 2);
477
478 err = mlx5r_umr_update_xlt(mr, 0,
479 MLX5_IMR_MTT_ENTRIES,
480 PAGE_SHIFT,
481 MLX5_IB_UPD_XLT_ZAP |
482 MLX5_IB_UPD_XLT_ENABLE);
483 if (err) {
484 ret = ERR_PTR(err);
485 goto out_mr;
486 }
487
488 xa_lock(&imr->implicit_children);
489 ret = __xa_cmpxchg(&imr->implicit_children, idx, NULL, mr,
490 GFP_KERNEL);
491 if (unlikely(ret)) {
492 if (xa_is_err(ret)) {
493 ret = ERR_PTR(xa_err(ret));
494 goto out_lock;
495 }
496 /*
497 * Another thread beat us to creating the child mr, use
498 * theirs.
499 */
500 refcount_inc(&ret->mmkey.usecount);
501 goto out_lock;
502 }
503 xa_unlock(&imr->implicit_children);
504
505 if (MLX5_CAP_ODP(dev->mdev, mem_page_fault)) {
506 ret = xa_store(&dev->odp_mkeys, mlx5_base_mkey(mr->mmkey.key),
507 &mr->mmkey, GFP_KERNEL);
508 if (xa_is_err(ret)) {
509 ret = ERR_PTR(xa_err(ret));
510 xa_erase(&imr->implicit_children, idx);
511 goto out_mr;
512 }
513 mr->mmkey.type = MLX5_MKEY_IMPLICIT_CHILD;
514 }
515 mlx5_ib_dbg(mr_to_mdev(imr), "key %x mr %p\n", mr->mmkey.key, mr);
516 return mr;
517
518 out_lock:
519 xa_unlock(&imr->implicit_children);
520 out_mr:
521 mlx5_ib_dereg_mr(&mr->ibmr, NULL);
522 return ret;
523 }
524
525 /*
526 * When using memory scheme ODP, implicit MRs can't use the reserved null mkey
527 * and each implicit MR needs to assign a private null mkey to get the page
528 * faults on.
529 * The null mkey is created with the properties to enable getting the page
530 * fault for every time it is accessed and having all relevant access flags.
531 */
alloc_implicit_mr_null_mkey(struct mlx5_ib_dev * dev,struct mlx5_ib_mr * imr,struct mlx5_ib_pd * pd)532 static int alloc_implicit_mr_null_mkey(struct mlx5_ib_dev *dev,
533 struct mlx5_ib_mr *imr,
534 struct mlx5_ib_pd *pd)
535 {
536 size_t inlen = MLX5_ST_SZ_BYTES(create_mkey_in) + 64;
537 void *mkc;
538 u32 *in;
539 int err;
540
541 in = kzalloc(inlen, GFP_KERNEL);
542 if (!in)
543 return -ENOMEM;
544
545 MLX5_SET(create_mkey_in, in, translations_octword_actual_size, 4);
546 MLX5_SET(create_mkey_in, in, pg_access, 1);
547
548 mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
549 MLX5_SET(mkc, mkc, a, 1);
550 MLX5_SET(mkc, mkc, rw, 1);
551 MLX5_SET(mkc, mkc, rr, 1);
552 MLX5_SET(mkc, mkc, lw, 1);
553 MLX5_SET(mkc, mkc, lr, 1);
554 MLX5_SET(mkc, mkc, free, 0);
555 MLX5_SET(mkc, mkc, umr_en, 0);
556 MLX5_SET(mkc, mkc, access_mode_1_0, MLX5_MKC_ACCESS_MODE_MTT);
557
558 MLX5_SET(mkc, mkc, translations_octword_size, 4);
559 MLX5_SET(mkc, mkc, log_page_size, 61);
560 MLX5_SET(mkc, mkc, length64, 1);
561 MLX5_SET(mkc, mkc, pd, pd->pdn);
562 MLX5_SET64(mkc, mkc, start_addr, 0);
563 MLX5_SET(mkc, mkc, qpn, 0xffffff);
564
565 err = mlx5_core_create_mkey(dev->mdev, &imr->null_mmkey.key, in, inlen);
566 if (err)
567 goto free_in;
568
569 imr->null_mmkey.type = MLX5_MKEY_NULL;
570
571 free_in:
572 kfree(in);
573 return err;
574 }
575
mlx5_ib_alloc_implicit_mr(struct mlx5_ib_pd * pd,int access_flags)576 struct mlx5_ib_mr *mlx5_ib_alloc_implicit_mr(struct mlx5_ib_pd *pd,
577 int access_flags)
578 {
579 struct mlx5_ib_dev *dev = to_mdev(pd->ibpd.device);
580 struct ib_umem_odp *umem_odp;
581 struct mlx5_ib_mr *imr;
582 int err;
583
584 if (!mlx5r_umr_can_load_pas(dev, MLX5_IMR_MTT_ENTRIES * PAGE_SIZE))
585 return ERR_PTR(-EOPNOTSUPP);
586
587 umem_odp = ib_umem_odp_alloc_implicit(&dev->ib_dev, access_flags);
588 if (IS_ERR(umem_odp))
589 return ERR_CAST(umem_odp);
590
591 imr = mlx5_mr_cache_alloc(dev, access_flags, MLX5_MKC_ACCESS_MODE_KSM,
592 mlx5_imr_ksm_entries);
593 if (IS_ERR(imr)) {
594 ib_umem_odp_release(umem_odp);
595 return imr;
596 }
597
598 imr->access_flags = access_flags;
599 imr->ibmr.pd = &pd->ibpd;
600 imr->ibmr.iova = 0;
601 imr->umem = &umem_odp->umem;
602 imr->ibmr.lkey = imr->mmkey.key;
603 imr->ibmr.rkey = imr->mmkey.key;
604 imr->ibmr.device = &dev->ib_dev;
605 imr->is_odp_implicit = true;
606 xa_init(&imr->implicit_children);
607
608 if (MLX5_CAP_ODP(dev->mdev, mem_page_fault)) {
609 err = alloc_implicit_mr_null_mkey(dev, imr, pd);
610 if (err)
611 goto out_mr;
612
613 err = mlx5r_store_odp_mkey(dev, &imr->null_mmkey);
614 if (err)
615 goto out_mr;
616 }
617
618 err = mlx5r_umr_update_xlt(imr, 0,
619 mlx5_imr_ksm_entries,
620 MLX5_KSM_PAGE_SHIFT,
621 MLX5_IB_UPD_XLT_INDIRECT |
622 MLX5_IB_UPD_XLT_ZAP |
623 MLX5_IB_UPD_XLT_ENABLE);
624 if (err)
625 goto out_mr;
626
627 err = mlx5r_store_odp_mkey(dev, &imr->mmkey);
628 if (err)
629 goto out_mr;
630
631 mlx5_ib_dbg(dev, "key %x mr %p\n", imr->mmkey.key, imr);
632 return imr;
633 out_mr:
634 mlx5_ib_err(dev, "Failed to register MKEY %d\n", err);
635 mlx5_ib_dereg_mr(&imr->ibmr, NULL);
636 return ERR_PTR(err);
637 }
638
mlx5_ib_free_odp_mr(struct mlx5_ib_mr * mr)639 void mlx5_ib_free_odp_mr(struct mlx5_ib_mr *mr)
640 {
641 struct mlx5_ib_mr *mtt;
642 unsigned long idx;
643
644 /*
645 * If this is an implicit MR it is already invalidated so we can just
646 * delete the children mkeys.
647 */
648 xa_for_each(&mr->implicit_children, idx, mtt) {
649 xa_erase(&mr->implicit_children, idx);
650 mlx5_ib_dereg_mr(&mtt->ibmr, NULL);
651 }
652
653 if (mr->null_mmkey.key) {
654 xa_erase(&mr_to_mdev(mr)->odp_mkeys,
655 mlx5_base_mkey(mr->null_mmkey.key));
656
657 mlx5_core_destroy_mkey(mr_to_mdev(mr)->mdev,
658 mr->null_mmkey.key);
659 }
660 }
661
662 #define MLX5_PF_FLAGS_DOWNGRADE BIT(1)
663 #define MLX5_PF_FLAGS_SNAPSHOT BIT(2)
664 #define MLX5_PF_FLAGS_ENABLE BIT(3)
pagefault_real_mr(struct mlx5_ib_mr * mr,struct ib_umem_odp * odp,u64 user_va,size_t bcnt,u32 * bytes_mapped,u32 flags)665 static int pagefault_real_mr(struct mlx5_ib_mr *mr, struct ib_umem_odp *odp,
666 u64 user_va, size_t bcnt, u32 *bytes_mapped,
667 u32 flags)
668 {
669 int page_shift, ret, np;
670 bool downgrade = flags & MLX5_PF_FLAGS_DOWNGRADE;
671 u64 access_mask;
672 u64 start_idx;
673 bool fault = !(flags & MLX5_PF_FLAGS_SNAPSHOT);
674 u32 xlt_flags = MLX5_IB_UPD_XLT_ATOMIC;
675
676 if (flags & MLX5_PF_FLAGS_ENABLE)
677 xlt_flags |= MLX5_IB_UPD_XLT_ENABLE;
678
679 page_shift = odp->page_shift;
680 start_idx = (user_va - ib_umem_start(odp)) >> page_shift;
681 access_mask = ODP_READ_ALLOWED_BIT;
682
683 if (odp->umem.writable && !downgrade)
684 access_mask |= ODP_WRITE_ALLOWED_BIT;
685
686 np = ib_umem_odp_map_dma_and_lock(odp, user_va, bcnt, access_mask, fault);
687 if (np < 0)
688 return np;
689
690 /*
691 * No need to check whether the MTTs really belong to this MR, since
692 * ib_umem_odp_map_dma_and_lock already checks this.
693 */
694 ret = mlx5r_umr_update_xlt(mr, start_idx, np, page_shift, xlt_flags);
695 mutex_unlock(&odp->umem_mutex);
696
697 if (ret < 0) {
698 if (ret != -EAGAIN)
699 mlx5_ib_err(mr_to_mdev(mr),
700 "Failed to update mkey page tables\n");
701 goto out;
702 }
703
704 if (bytes_mapped) {
705 u32 new_mappings = (np << page_shift) -
706 (user_va - round_down(user_va, 1 << page_shift));
707
708 *bytes_mapped += min_t(u32, new_mappings, bcnt);
709 }
710
711 return np << (page_shift - PAGE_SHIFT);
712
713 out:
714 return ret;
715 }
716
pagefault_implicit_mr(struct mlx5_ib_mr * imr,struct ib_umem_odp * odp_imr,u64 user_va,size_t bcnt,u32 * bytes_mapped,u32 flags)717 static int pagefault_implicit_mr(struct mlx5_ib_mr *imr,
718 struct ib_umem_odp *odp_imr, u64 user_va,
719 size_t bcnt, u32 *bytes_mapped, u32 flags)
720 {
721 unsigned long end_idx = (user_va + bcnt - 1) >> MLX5_IMR_MTT_SHIFT;
722 unsigned long upd_start_idx = end_idx + 1;
723 unsigned long upd_len = 0;
724 unsigned long npages = 0;
725 int err;
726 int ret;
727
728 if (unlikely(user_va >= mlx5_imr_ksm_entries * MLX5_IMR_MTT_SIZE ||
729 mlx5_imr_ksm_entries * MLX5_IMR_MTT_SIZE - user_va < bcnt))
730 return -EFAULT;
731
732 /* Fault each child mr that intersects with our interval. */
733 while (bcnt) {
734 unsigned long idx = user_va >> MLX5_IMR_MTT_SHIFT;
735 struct ib_umem_odp *umem_odp;
736 struct mlx5_ib_mr *mtt;
737 u64 len;
738
739 xa_lock(&imr->implicit_children);
740 mtt = xa_load(&imr->implicit_children, idx);
741 if (unlikely(!mtt)) {
742 xa_unlock(&imr->implicit_children);
743 mtt = implicit_get_child_mr(imr, idx);
744 if (IS_ERR(mtt)) {
745 ret = PTR_ERR(mtt);
746 goto out;
747 }
748 upd_start_idx = min(upd_start_idx, idx);
749 upd_len = idx - upd_start_idx + 1;
750 } else {
751 refcount_inc(&mtt->mmkey.usecount);
752 xa_unlock(&imr->implicit_children);
753 }
754
755 umem_odp = to_ib_umem_odp(mtt->umem);
756 len = min_t(u64, user_va + bcnt, ib_umem_end(umem_odp)) -
757 user_va;
758
759 ret = pagefault_real_mr(mtt, umem_odp, user_va, len,
760 bytes_mapped, flags);
761
762 mlx5r_deref_odp_mkey(&mtt->mmkey);
763
764 if (ret < 0)
765 goto out;
766 user_va += len;
767 bcnt -= len;
768 npages += ret;
769 }
770
771 ret = npages;
772
773 /*
774 * Any time the implicit_children are changed we must perform an
775 * update of the xlt before exiting to ensure the HW and the
776 * implicit_children remains synchronized.
777 */
778 out:
779 if (likely(!upd_len))
780 return ret;
781
782 /*
783 * Notice this is not strictly ordered right, the KSM is updated after
784 * the implicit_children is updated, so a parallel page fault could
785 * see a MR that is not yet visible in the KSM. This is similar to a
786 * parallel page fault seeing a MR that is being concurrently removed
787 * from the KSM. Both of these improbable situations are resolved
788 * safely by resuming the HW and then taking another page fault. The
789 * next pagefault handler will see the new information.
790 */
791 mutex_lock(&odp_imr->umem_mutex);
792 err = mlx5r_umr_update_xlt(imr, upd_start_idx, upd_len, 0,
793 MLX5_IB_UPD_XLT_INDIRECT |
794 MLX5_IB_UPD_XLT_ATOMIC);
795 mutex_unlock(&odp_imr->umem_mutex);
796 if (err) {
797 mlx5_ib_err(mr_to_mdev(imr), "Failed to update PAS\n");
798 return err;
799 }
800 return ret;
801 }
802
pagefault_dmabuf_mr(struct mlx5_ib_mr * mr,size_t bcnt,u32 * bytes_mapped,u32 flags)803 static int pagefault_dmabuf_mr(struct mlx5_ib_mr *mr, size_t bcnt,
804 u32 *bytes_mapped, u32 flags)
805 {
806 struct ib_umem_dmabuf *umem_dmabuf = to_ib_umem_dmabuf(mr->umem);
807 u32 xlt_flags = 0;
808 int err;
809 unsigned long page_size;
810
811 if (flags & MLX5_PF_FLAGS_ENABLE)
812 xlt_flags |= MLX5_IB_UPD_XLT_ENABLE;
813
814 dma_resv_lock(umem_dmabuf->attach->dmabuf->resv, NULL);
815 err = ib_umem_dmabuf_map_pages(umem_dmabuf);
816 if (err) {
817 dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv);
818 return err;
819 }
820
821 page_size = mlx5_umem_dmabuf_find_best_pgsz(umem_dmabuf);
822 if (!page_size) {
823 ib_umem_dmabuf_unmap_pages(umem_dmabuf);
824 err = -EINVAL;
825 } else {
826 if (mr->data_direct)
827 err = mlx5r_umr_update_data_direct_ksm_pas(mr, xlt_flags);
828 else
829 err = mlx5r_umr_update_mr_pas(mr, xlt_flags);
830 }
831 dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv);
832
833 if (err)
834 return err;
835
836 if (bytes_mapped)
837 *bytes_mapped += bcnt;
838
839 return ib_umem_num_pages(mr->umem);
840 }
841
842 /*
843 * Returns:
844 * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are
845 * not accessible, or the MR is no longer valid.
846 * -EAGAIN/-ENOMEM: The operation should be retried
847 *
848 * -EINVAL/others: General internal malfunction
849 * >0: Number of pages mapped
850 */
pagefault_mr(struct mlx5_ib_mr * mr,u64 io_virt,size_t bcnt,u32 * bytes_mapped,u32 flags,bool permissive_fault)851 static int pagefault_mr(struct mlx5_ib_mr *mr, u64 io_virt, size_t bcnt,
852 u32 *bytes_mapped, u32 flags, bool permissive_fault)
853 {
854 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
855
856 if (unlikely(io_virt < mr->ibmr.iova) && !permissive_fault)
857 return -EFAULT;
858
859 if (mr->umem->is_dmabuf)
860 return pagefault_dmabuf_mr(mr, bcnt, bytes_mapped, flags);
861
862 if (!odp->is_implicit_odp) {
863 u64 offset = io_virt < mr->ibmr.iova ? 0 : io_virt - mr->ibmr.iova;
864 u64 user_va;
865
866 if (check_add_overflow(offset, (u64)odp->umem.address,
867 &user_va))
868 return -EFAULT;
869
870 if (permissive_fault) {
871 if (user_va < ib_umem_start(odp))
872 user_va = ib_umem_start(odp);
873 if ((user_va + bcnt) > ib_umem_end(odp))
874 bcnt = ib_umem_end(odp) - user_va;
875 } else if (unlikely(user_va >= ib_umem_end(odp) ||
876 ib_umem_end(odp) - user_va < bcnt))
877 return -EFAULT;
878 return pagefault_real_mr(mr, odp, user_va, bcnt, bytes_mapped,
879 flags);
880 }
881 return pagefault_implicit_mr(mr, odp, io_virt, bcnt, bytes_mapped,
882 flags);
883 }
884
mlx5_ib_init_odp_mr(struct mlx5_ib_mr * mr)885 int mlx5_ib_init_odp_mr(struct mlx5_ib_mr *mr)
886 {
887 int ret;
888
889 ret = pagefault_real_mr(mr, to_ib_umem_odp(mr->umem), mr->umem->address,
890 mr->umem->length, NULL,
891 MLX5_PF_FLAGS_SNAPSHOT | MLX5_PF_FLAGS_ENABLE);
892 return ret >= 0 ? 0 : ret;
893 }
894
mlx5_ib_init_dmabuf_mr(struct mlx5_ib_mr * mr)895 int mlx5_ib_init_dmabuf_mr(struct mlx5_ib_mr *mr)
896 {
897 int ret;
898
899 ret = pagefault_dmabuf_mr(mr, mr->umem->length, NULL,
900 MLX5_PF_FLAGS_ENABLE);
901
902 return ret >= 0 ? 0 : ret;
903 }
904
905 struct pf_frame {
906 struct pf_frame *next;
907 u32 key;
908 u64 io_virt;
909 size_t bcnt;
910 int depth;
911 };
912
mkey_is_eq(struct mlx5_ib_mkey * mmkey,u32 key)913 static bool mkey_is_eq(struct mlx5_ib_mkey *mmkey, u32 key)
914 {
915 if (!mmkey)
916 return false;
917 if (mmkey->type == MLX5_MKEY_MW ||
918 mmkey->type == MLX5_MKEY_INDIRECT_DEVX)
919 return mlx5_base_mkey(mmkey->key) == mlx5_base_mkey(key);
920 return mmkey->key == key;
921 }
922
find_odp_mkey(struct mlx5_ib_dev * dev,u32 key)923 static struct mlx5_ib_mkey *find_odp_mkey(struct mlx5_ib_dev *dev, u32 key)
924 {
925 struct mlx5_ib_mkey *mmkey;
926
927 xa_lock(&dev->odp_mkeys);
928 mmkey = xa_load(&dev->odp_mkeys, mlx5_base_mkey(key));
929 if (!mmkey) {
930 mmkey = ERR_PTR(-ENOENT);
931 goto out;
932 }
933 if (!mkey_is_eq(mmkey, key)) {
934 mmkey = ERR_PTR(-EFAULT);
935 goto out;
936 }
937 refcount_inc(&mmkey->usecount);
938 out:
939 xa_unlock(&dev->odp_mkeys);
940
941 return mmkey;
942 }
943
944 /*
945 * Handle a single data segment in a page-fault WQE or RDMA region.
946 *
947 * Returns number of OS pages retrieved on success. The caller may continue to
948 * the next data segment.
949 * Can return the following error codes:
950 * -EAGAIN to designate a temporary error. The caller will abort handling the
951 * page fault and resolve it.
952 * -EFAULT when there's an error mapping the requested pages. The caller will
953 * abort the page fault handling.
954 */
pagefault_single_data_segment(struct mlx5_ib_dev * dev,struct ib_pd * pd,u32 key,u64 io_virt,size_t bcnt,u32 * bytes_committed,u32 * bytes_mapped)955 static int pagefault_single_data_segment(struct mlx5_ib_dev *dev,
956 struct ib_pd *pd, u32 key,
957 u64 io_virt, size_t bcnt,
958 u32 *bytes_committed,
959 u32 *bytes_mapped)
960 {
961 int npages = 0, ret, i, outlen, cur_outlen = 0, depth = 0;
962 struct pf_frame *head = NULL, *frame;
963 struct mlx5_ib_mkey *mmkey;
964 struct mlx5_ib_mr *mr;
965 struct mlx5_klm *pklm;
966 u32 *out = NULL;
967 size_t offset;
968
969 io_virt += *bytes_committed;
970 bcnt -= *bytes_committed;
971 next_mr:
972 mmkey = find_odp_mkey(dev, key);
973 if (IS_ERR(mmkey)) {
974 ret = PTR_ERR(mmkey);
975 if (ret == -ENOENT) {
976 mlx5_ib_dbg(
977 dev,
978 "skipping non ODP MR (lkey=0x%06x) in page fault handler.\n",
979 key);
980 if (bytes_mapped)
981 *bytes_mapped += bcnt;
982 /*
983 * The user could specify a SGL with multiple lkeys and
984 * only some of them are ODP. Treat the non-ODP ones as
985 * fully faulted.
986 */
987 ret = 0;
988 }
989 goto end;
990 }
991
992 switch (mmkey->type) {
993 case MLX5_MKEY_MR:
994 mr = container_of(mmkey, struct mlx5_ib_mr, mmkey);
995
996 ret = pagefault_mr(mr, io_virt, bcnt, bytes_mapped, 0, false);
997 if (ret < 0)
998 goto end;
999
1000 mlx5_update_odp_stats(mr, faults, ret);
1001
1002 npages += ret;
1003 ret = 0;
1004 break;
1005
1006 case MLX5_MKEY_MW:
1007 case MLX5_MKEY_INDIRECT_DEVX:
1008 if (depth >= MLX5_CAP_GEN(dev->mdev, max_indirection)) {
1009 mlx5_ib_dbg(dev, "indirection level exceeded\n");
1010 ret = -EFAULT;
1011 goto end;
1012 }
1013
1014 outlen = MLX5_ST_SZ_BYTES(query_mkey_out) +
1015 sizeof(*pklm) * (mmkey->ndescs - 2);
1016
1017 if (outlen > cur_outlen) {
1018 kfree(out);
1019 out = kzalloc(outlen, GFP_KERNEL);
1020 if (!out) {
1021 ret = -ENOMEM;
1022 goto end;
1023 }
1024 cur_outlen = outlen;
1025 }
1026
1027 pklm = (struct mlx5_klm *)MLX5_ADDR_OF(query_mkey_out, out,
1028 bsf0_klm0_pas_mtt0_1);
1029
1030 ret = mlx5_core_query_mkey(dev->mdev, mmkey->key, out, outlen);
1031 if (ret)
1032 goto end;
1033
1034 offset = io_virt - MLX5_GET64(query_mkey_out, out,
1035 memory_key_mkey_entry.start_addr);
1036
1037 for (i = 0; bcnt && i < mmkey->ndescs; i++, pklm++) {
1038 if (offset >= be32_to_cpu(pklm->bcount)) {
1039 offset -= be32_to_cpu(pklm->bcount);
1040 continue;
1041 }
1042
1043 frame = kzalloc(sizeof(*frame), GFP_KERNEL);
1044 if (!frame) {
1045 ret = -ENOMEM;
1046 goto end;
1047 }
1048
1049 frame->key = be32_to_cpu(pklm->key);
1050 frame->io_virt = be64_to_cpu(pklm->va) + offset;
1051 frame->bcnt = min_t(size_t, bcnt,
1052 be32_to_cpu(pklm->bcount) - offset);
1053 frame->depth = depth + 1;
1054 frame->next = head;
1055 head = frame;
1056
1057 bcnt -= frame->bcnt;
1058 offset = 0;
1059 }
1060 break;
1061
1062 default:
1063 mlx5_ib_dbg(dev, "wrong mkey type %d\n", mmkey->type);
1064 ret = -EFAULT;
1065 goto end;
1066 }
1067
1068 if (head) {
1069 frame = head;
1070 head = frame->next;
1071
1072 key = frame->key;
1073 io_virt = frame->io_virt;
1074 bcnt = frame->bcnt;
1075 depth = frame->depth;
1076 kfree(frame);
1077
1078 mlx5r_deref_odp_mkey(mmkey);
1079 goto next_mr;
1080 }
1081
1082 end:
1083 if (!IS_ERR(mmkey))
1084 mlx5r_deref_odp_mkey(mmkey);
1085 while (head) {
1086 frame = head;
1087 head = frame->next;
1088 kfree(frame);
1089 }
1090 kfree(out);
1091
1092 *bytes_committed = 0;
1093 return ret ? ret : npages;
1094 }
1095
1096 /*
1097 * Parse a series of data segments for page fault handling.
1098 *
1099 * @dev: Pointer to mlx5 IB device
1100 * @pfault: contains page fault information.
1101 * @wqe: points at the first data segment in the WQE.
1102 * @wqe_end: points after the end of the WQE.
1103 * @bytes_mapped: receives the number of bytes that the function was able to
1104 * map. This allows the caller to decide intelligently whether
1105 * enough memory was mapped to resolve the page fault
1106 * successfully (e.g. enough for the next MTU, or the entire
1107 * WQE).
1108 * @total_wqe_bytes: receives the total data size of this WQE in bytes (minus
1109 * the committed bytes).
1110 * @receive_queue: receive WQE end of sg list
1111 *
1112 * Returns the number of pages loaded if positive, zero for an empty WQE, or a
1113 * negative error code.
1114 */
pagefault_data_segments(struct mlx5_ib_dev * dev,struct mlx5_pagefault * pfault,void * wqe,void * wqe_end,u32 * bytes_mapped,u32 * total_wqe_bytes,bool receive_queue)1115 static int pagefault_data_segments(struct mlx5_ib_dev *dev,
1116 struct mlx5_pagefault *pfault,
1117 void *wqe,
1118 void *wqe_end, u32 *bytes_mapped,
1119 u32 *total_wqe_bytes, bool receive_queue)
1120 {
1121 int ret = 0, npages = 0;
1122 u64 io_virt;
1123 __be32 key;
1124 u32 byte_count;
1125 size_t bcnt;
1126 int inline_segment;
1127
1128 if (bytes_mapped)
1129 *bytes_mapped = 0;
1130 if (total_wqe_bytes)
1131 *total_wqe_bytes = 0;
1132
1133 while (wqe < wqe_end) {
1134 struct mlx5_wqe_data_seg *dseg = wqe;
1135
1136 io_virt = be64_to_cpu(dseg->addr);
1137 key = dseg->lkey;
1138 byte_count = be32_to_cpu(dseg->byte_count);
1139 inline_segment = !!(byte_count & MLX5_INLINE_SEG);
1140 bcnt = byte_count & ~MLX5_INLINE_SEG;
1141
1142 if (inline_segment) {
1143 bcnt = bcnt & MLX5_WQE_INLINE_SEG_BYTE_COUNT_MASK;
1144 wqe += ALIGN(sizeof(struct mlx5_wqe_inline_seg) + bcnt,
1145 16);
1146 } else {
1147 wqe += sizeof(*dseg);
1148 }
1149
1150 /* receive WQE end of sg list. */
1151 if (receive_queue && bcnt == 0 &&
1152 key == dev->mkeys.terminate_scatter_list_mkey &&
1153 io_virt == 0)
1154 break;
1155
1156 if (!inline_segment && total_wqe_bytes) {
1157 *total_wqe_bytes += bcnt - min_t(size_t, bcnt,
1158 pfault->bytes_committed);
1159 }
1160
1161 /* A zero length data segment designates a length of 2GB. */
1162 if (bcnt == 0)
1163 bcnt = 1U << 31;
1164
1165 if (inline_segment || bcnt <= pfault->bytes_committed) {
1166 pfault->bytes_committed -=
1167 min_t(size_t, bcnt,
1168 pfault->bytes_committed);
1169 continue;
1170 }
1171
1172 ret = pagefault_single_data_segment(dev, NULL, be32_to_cpu(key),
1173 io_virt, bcnt,
1174 &pfault->bytes_committed,
1175 bytes_mapped);
1176 if (ret < 0)
1177 break;
1178 npages += ret;
1179 }
1180
1181 return ret < 0 ? ret : npages;
1182 }
1183
1184 /*
1185 * Parse initiator WQE. Advances the wqe pointer to point at the
1186 * scatter-gather list, and set wqe_end to the end of the WQE.
1187 */
mlx5_ib_mr_initiator_pfault_handler(struct mlx5_ib_dev * dev,struct mlx5_pagefault * pfault,struct mlx5_ib_qp * qp,void ** wqe,void ** wqe_end,int wqe_length)1188 static int mlx5_ib_mr_initiator_pfault_handler(
1189 struct mlx5_ib_dev *dev, struct mlx5_pagefault *pfault,
1190 struct mlx5_ib_qp *qp, void **wqe, void **wqe_end, int wqe_length)
1191 {
1192 struct mlx5_wqe_ctrl_seg *ctrl = *wqe;
1193 u16 wqe_index = pfault->wqe.wqe_index;
1194 struct mlx5_base_av *av;
1195 unsigned ds, opcode;
1196 u32 qpn = qp->trans_qp.base.mqp.qpn;
1197
1198 ds = be32_to_cpu(ctrl->qpn_ds) & MLX5_WQE_CTRL_DS_MASK;
1199 if (ds * MLX5_WQE_DS_UNITS > wqe_length) {
1200 mlx5_ib_err(dev, "Unable to read the complete WQE. ds = 0x%x, ret = 0x%x\n",
1201 ds, wqe_length);
1202 return -EFAULT;
1203 }
1204
1205 if (ds == 0) {
1206 mlx5_ib_err(dev, "Got WQE with zero DS. wqe_index=%x, qpn=%x\n",
1207 wqe_index, qpn);
1208 return -EFAULT;
1209 }
1210
1211 *wqe_end = *wqe + ds * MLX5_WQE_DS_UNITS;
1212 *wqe += sizeof(*ctrl);
1213
1214 opcode = be32_to_cpu(ctrl->opmod_idx_opcode) &
1215 MLX5_WQE_CTRL_OPCODE_MASK;
1216
1217 if (qp->type == IB_QPT_XRC_INI)
1218 *wqe += sizeof(struct mlx5_wqe_xrc_seg);
1219
1220 if (qp->type == IB_QPT_UD || qp->type == MLX5_IB_QPT_DCI) {
1221 av = *wqe;
1222 if (av->dqp_dct & cpu_to_be32(MLX5_EXTENDED_UD_AV))
1223 *wqe += sizeof(struct mlx5_av);
1224 else
1225 *wqe += sizeof(struct mlx5_base_av);
1226 }
1227
1228 switch (opcode) {
1229 case MLX5_OPCODE_RDMA_WRITE:
1230 case MLX5_OPCODE_RDMA_WRITE_IMM:
1231 case MLX5_OPCODE_RDMA_READ:
1232 *wqe += sizeof(struct mlx5_wqe_raddr_seg);
1233 break;
1234 case MLX5_OPCODE_ATOMIC_CS:
1235 case MLX5_OPCODE_ATOMIC_FA:
1236 *wqe += sizeof(struct mlx5_wqe_raddr_seg);
1237 *wqe += sizeof(struct mlx5_wqe_atomic_seg);
1238 break;
1239 }
1240
1241 return 0;
1242 }
1243
1244 /*
1245 * Parse responder WQE and set wqe_end to the end of the WQE.
1246 */
mlx5_ib_mr_responder_pfault_handler_srq(struct mlx5_ib_dev * dev,struct mlx5_ib_srq * srq,void ** wqe,void ** wqe_end,int wqe_length)1247 static int mlx5_ib_mr_responder_pfault_handler_srq(struct mlx5_ib_dev *dev,
1248 struct mlx5_ib_srq *srq,
1249 void **wqe, void **wqe_end,
1250 int wqe_length)
1251 {
1252 int wqe_size = 1 << srq->msrq.wqe_shift;
1253
1254 if (wqe_size > wqe_length) {
1255 mlx5_ib_err(dev, "Couldn't read all of the receive WQE's content\n");
1256 return -EFAULT;
1257 }
1258
1259 *wqe_end = *wqe + wqe_size;
1260 *wqe += sizeof(struct mlx5_wqe_srq_next_seg);
1261
1262 return 0;
1263 }
1264
mlx5_ib_mr_responder_pfault_handler_rq(struct mlx5_ib_dev * dev,struct mlx5_ib_qp * qp,void * wqe,void ** wqe_end,int wqe_length)1265 static int mlx5_ib_mr_responder_pfault_handler_rq(struct mlx5_ib_dev *dev,
1266 struct mlx5_ib_qp *qp,
1267 void *wqe, void **wqe_end,
1268 int wqe_length)
1269 {
1270 struct mlx5_ib_wq *wq = &qp->rq;
1271 int wqe_size = 1 << wq->wqe_shift;
1272
1273 if (qp->flags_en & MLX5_QP_FLAG_SIGNATURE) {
1274 mlx5_ib_err(dev, "ODP fault with WQE signatures is not supported\n");
1275 return -EFAULT;
1276 }
1277
1278 if (wqe_size > wqe_length) {
1279 mlx5_ib_err(dev, "Couldn't read all of the receive WQE's content\n");
1280 return -EFAULT;
1281 }
1282
1283 *wqe_end = wqe + wqe_size;
1284
1285 return 0;
1286 }
1287
odp_get_rsc(struct mlx5_ib_dev * dev,u32 wq_num,int pf_type)1288 static inline struct mlx5_core_rsc_common *odp_get_rsc(struct mlx5_ib_dev *dev,
1289 u32 wq_num, int pf_type)
1290 {
1291 struct mlx5_core_rsc_common *common = NULL;
1292 struct mlx5_core_srq *srq;
1293
1294 switch (pf_type) {
1295 case MLX5_WQE_PF_TYPE_RMP:
1296 srq = mlx5_cmd_get_srq(dev, wq_num);
1297 if (srq)
1298 common = &srq->common;
1299 break;
1300 case MLX5_WQE_PF_TYPE_REQ_SEND_OR_WRITE:
1301 case MLX5_WQE_PF_TYPE_RESP:
1302 case MLX5_WQE_PF_TYPE_REQ_READ_OR_ATOMIC:
1303 common = mlx5_core_res_hold(dev, wq_num, MLX5_RES_QP);
1304 break;
1305 default:
1306 break;
1307 }
1308
1309 return common;
1310 }
1311
res_to_qp(struct mlx5_core_rsc_common * res)1312 static inline struct mlx5_ib_qp *res_to_qp(struct mlx5_core_rsc_common *res)
1313 {
1314 struct mlx5_core_qp *mqp = (struct mlx5_core_qp *)res;
1315
1316 return to_mibqp(mqp);
1317 }
1318
res_to_srq(struct mlx5_core_rsc_common * res)1319 static inline struct mlx5_ib_srq *res_to_srq(struct mlx5_core_rsc_common *res)
1320 {
1321 struct mlx5_core_srq *msrq =
1322 container_of(res, struct mlx5_core_srq, common);
1323
1324 return to_mibsrq(msrq);
1325 }
1326
mlx5_ib_mr_wqe_pfault_handler(struct mlx5_ib_dev * dev,struct mlx5_pagefault * pfault)1327 static void mlx5_ib_mr_wqe_pfault_handler(struct mlx5_ib_dev *dev,
1328 struct mlx5_pagefault *pfault)
1329 {
1330 bool sq = pfault->type & MLX5_PFAULT_REQUESTOR;
1331 u16 wqe_index = pfault->wqe.wqe_index;
1332 void *wqe, *wqe_start = NULL, *wqe_end = NULL;
1333 u32 bytes_mapped, total_wqe_bytes;
1334 struct mlx5_core_rsc_common *res;
1335 int resume_with_error = 1;
1336 struct mlx5_ib_qp *qp;
1337 size_t bytes_copied;
1338 int ret = 0;
1339
1340 res = odp_get_rsc(dev, pfault->wqe.wq_num, pfault->type);
1341 if (!res) {
1342 mlx5_ib_dbg(dev, "wqe page fault for missing resource %d\n", pfault->wqe.wq_num);
1343 return;
1344 }
1345
1346 if (res->res != MLX5_RES_QP && res->res != MLX5_RES_SRQ &&
1347 res->res != MLX5_RES_XSRQ) {
1348 mlx5_ib_err(dev, "wqe page fault for unsupported type %d\n",
1349 pfault->type);
1350 goto resolve_page_fault;
1351 }
1352
1353 wqe_start = (void *)__get_free_page(GFP_KERNEL);
1354 if (!wqe_start) {
1355 mlx5_ib_err(dev, "Error allocating memory for IO page fault handling.\n");
1356 goto resolve_page_fault;
1357 }
1358
1359 wqe = wqe_start;
1360 qp = (res->res == MLX5_RES_QP) ? res_to_qp(res) : NULL;
1361 if (qp && sq) {
1362 ret = mlx5_ib_read_wqe_sq(qp, wqe_index, wqe, PAGE_SIZE,
1363 &bytes_copied);
1364 if (ret)
1365 goto read_user;
1366 ret = mlx5_ib_mr_initiator_pfault_handler(
1367 dev, pfault, qp, &wqe, &wqe_end, bytes_copied);
1368 } else if (qp && !sq) {
1369 ret = mlx5_ib_read_wqe_rq(qp, wqe_index, wqe, PAGE_SIZE,
1370 &bytes_copied);
1371 if (ret)
1372 goto read_user;
1373 ret = mlx5_ib_mr_responder_pfault_handler_rq(
1374 dev, qp, wqe, &wqe_end, bytes_copied);
1375 } else if (!qp) {
1376 struct mlx5_ib_srq *srq = res_to_srq(res);
1377
1378 ret = mlx5_ib_read_wqe_srq(srq, wqe_index, wqe, PAGE_SIZE,
1379 &bytes_copied);
1380 if (ret)
1381 goto read_user;
1382 ret = mlx5_ib_mr_responder_pfault_handler_srq(
1383 dev, srq, &wqe, &wqe_end, bytes_copied);
1384 }
1385
1386 if (ret < 0 || wqe >= wqe_end)
1387 goto resolve_page_fault;
1388
1389 ret = pagefault_data_segments(dev, pfault, wqe, wqe_end, &bytes_mapped,
1390 &total_wqe_bytes, !sq);
1391 if (ret == -EAGAIN)
1392 goto out;
1393
1394 if (ret < 0 || total_wqe_bytes > bytes_mapped)
1395 goto resolve_page_fault;
1396
1397 out:
1398 ret = 0;
1399 resume_with_error = 0;
1400
1401 read_user:
1402 if (ret)
1403 mlx5_ib_err(
1404 dev,
1405 "Failed reading a WQE following page fault, error %d, wqe_index %x, qpn %llx\n",
1406 ret, wqe_index, pfault->token);
1407
1408 resolve_page_fault:
1409 mlx5_ib_page_fault_resume(dev, pfault, resume_with_error);
1410 mlx5_ib_dbg(dev, "PAGE FAULT completed. QP 0x%x resume_with_error=%d, type: 0x%x\n",
1411 pfault->wqe.wq_num, resume_with_error,
1412 pfault->type);
1413 mlx5_core_res_put(res);
1414 free_page((unsigned long)wqe_start);
1415 }
1416
pages_in_range(u64 address,u32 length)1417 static int pages_in_range(u64 address, u32 length)
1418 {
1419 return (ALIGN(address + length, PAGE_SIZE) -
1420 (address & PAGE_MASK)) >> PAGE_SHIFT;
1421 }
1422
mlx5_ib_mr_rdma_pfault_handler(struct mlx5_ib_dev * dev,struct mlx5_pagefault * pfault)1423 static void mlx5_ib_mr_rdma_pfault_handler(struct mlx5_ib_dev *dev,
1424 struct mlx5_pagefault *pfault)
1425 {
1426 u64 address;
1427 u32 length;
1428 u32 prefetch_len = pfault->bytes_committed;
1429 int prefetch_activated = 0;
1430 u32 rkey = pfault->rdma.r_key;
1431 int ret;
1432
1433 /* The RDMA responder handler handles the page fault in two parts.
1434 * First it brings the necessary pages for the current packet
1435 * (and uses the pfault context), and then (after resuming the QP)
1436 * prefetches more pages. The second operation cannot use the pfault
1437 * context and therefore uses the dummy_pfault context allocated on
1438 * the stack */
1439 pfault->rdma.rdma_va += pfault->bytes_committed;
1440 pfault->rdma.rdma_op_len -= min(pfault->bytes_committed,
1441 pfault->rdma.rdma_op_len);
1442 pfault->bytes_committed = 0;
1443
1444 address = pfault->rdma.rdma_va;
1445 length = pfault->rdma.rdma_op_len;
1446
1447 /* For some operations, the hardware cannot tell the exact message
1448 * length, and in those cases it reports zero. Use prefetch
1449 * logic. */
1450 if (length == 0) {
1451 prefetch_activated = 1;
1452 length = pfault->rdma.packet_size;
1453 prefetch_len = min(MAX_PREFETCH_LEN, prefetch_len);
1454 }
1455
1456 ret = pagefault_single_data_segment(dev, NULL, rkey, address, length,
1457 &pfault->bytes_committed, NULL);
1458 if (ret == -EAGAIN) {
1459 /* We're racing with an invalidation, don't prefetch */
1460 prefetch_activated = 0;
1461 } else if (ret < 0 || pages_in_range(address, length) > ret) {
1462 mlx5_ib_page_fault_resume(dev, pfault, 1);
1463 if (ret != -ENOENT)
1464 mlx5_ib_dbg(dev, "PAGE FAULT error %d. QP 0x%llx, type: 0x%x\n",
1465 ret, pfault->token, pfault->type);
1466 return;
1467 }
1468
1469 mlx5_ib_page_fault_resume(dev, pfault, 0);
1470 mlx5_ib_dbg(dev, "PAGE FAULT completed. QP 0x%llx, type: 0x%x, prefetch_activated: %d\n",
1471 pfault->token, pfault->type,
1472 prefetch_activated);
1473
1474 /* At this point, there might be a new pagefault already arriving in
1475 * the eq, switch to the dummy pagefault for the rest of the
1476 * processing. We're still OK with the objects being alive as the
1477 * work-queue is being fenced. */
1478
1479 if (prefetch_activated) {
1480 u32 bytes_committed = 0;
1481
1482 ret = pagefault_single_data_segment(dev, NULL, rkey, address,
1483 prefetch_len,
1484 &bytes_committed, NULL);
1485 if (ret < 0 && ret != -EAGAIN) {
1486 mlx5_ib_dbg(dev, "Prefetch failed. ret: %d, QP 0x%llx, address: 0x%.16llx, length = 0x%.16x\n",
1487 ret, pfault->token, address, prefetch_len);
1488 }
1489 }
1490 }
1491
1492 #define MLX5_MEMORY_PAGE_FAULT_FLAGS_LAST BIT(7)
mlx5_ib_mr_memory_pfault_handler(struct mlx5_ib_dev * dev,struct mlx5_pagefault * pfault)1493 static void mlx5_ib_mr_memory_pfault_handler(struct mlx5_ib_dev *dev,
1494 struct mlx5_pagefault *pfault)
1495 {
1496 u64 prefetch_va =
1497 pfault->memory.va - pfault->memory.prefetch_before_byte_count;
1498 size_t prefetch_size = pfault->memory.prefetch_before_byte_count +
1499 pfault->memory.fault_byte_count +
1500 pfault->memory.prefetch_after_byte_count;
1501 struct mlx5_ib_mkey *mmkey;
1502 struct mlx5_ib_mr *mr, *child_mr;
1503 int ret = 0;
1504
1505 mmkey = find_odp_mkey(dev, pfault->memory.mkey);
1506 if (IS_ERR(mmkey))
1507 goto err;
1508
1509 switch (mmkey->type) {
1510 case MLX5_MKEY_IMPLICIT_CHILD:
1511 child_mr = container_of(mmkey, struct mlx5_ib_mr, mmkey);
1512 mr = child_mr->parent;
1513 break;
1514 case MLX5_MKEY_NULL:
1515 mr = container_of(mmkey, struct mlx5_ib_mr, null_mmkey);
1516 break;
1517 default:
1518 mr = container_of(mmkey, struct mlx5_ib_mr, mmkey);
1519 break;
1520 }
1521
1522 /* If prefetch fails, handle only demanded page fault */
1523 ret = pagefault_mr(mr, prefetch_va, prefetch_size, NULL, 0, true);
1524 if (ret < 0) {
1525 ret = pagefault_mr(mr, pfault->memory.va,
1526 pfault->memory.fault_byte_count, NULL, 0,
1527 true);
1528 if (ret < 0)
1529 goto err;
1530 }
1531
1532 mlx5_update_odp_stats(mr, faults, ret);
1533 mlx5r_deref_odp_mkey(mmkey);
1534
1535 if (pfault->memory.flags & MLX5_MEMORY_PAGE_FAULT_FLAGS_LAST)
1536 mlx5_ib_page_fault_resume(dev, pfault, 0);
1537
1538 mlx5_ib_dbg(
1539 dev,
1540 "PAGE FAULT completed %s. token 0x%llx, mkey: 0x%x, va: 0x%llx, byte_count: 0x%x\n",
1541 pfault->memory.flags & MLX5_MEMORY_PAGE_FAULT_FLAGS_LAST ?
1542 "" :
1543 "without resume cmd",
1544 pfault->token, pfault->memory.mkey, pfault->memory.va,
1545 pfault->memory.fault_byte_count);
1546
1547 return;
1548
1549 err:
1550 if (!IS_ERR(mmkey))
1551 mlx5r_deref_odp_mkey(mmkey);
1552 mlx5_ib_page_fault_resume(dev, pfault, 1);
1553 mlx5_ib_dbg(
1554 dev,
1555 "PAGE FAULT error. token 0x%llx, mkey: 0x%x, va: 0x%llx, byte_count: 0x%x, err: %d\n",
1556 pfault->token, pfault->memory.mkey, pfault->memory.va,
1557 pfault->memory.fault_byte_count, ret);
1558 }
1559
mlx5_ib_pfault(struct mlx5_ib_dev * dev,struct mlx5_pagefault * pfault)1560 static void mlx5_ib_pfault(struct mlx5_ib_dev *dev, struct mlx5_pagefault *pfault)
1561 {
1562 u8 event_subtype = pfault->event_subtype;
1563
1564 switch (event_subtype) {
1565 case MLX5_PFAULT_SUBTYPE_WQE:
1566 mlx5_ib_mr_wqe_pfault_handler(dev, pfault);
1567 break;
1568 case MLX5_PFAULT_SUBTYPE_RDMA:
1569 mlx5_ib_mr_rdma_pfault_handler(dev, pfault);
1570 break;
1571 case MLX5_PFAULT_SUBTYPE_MEMORY:
1572 mlx5_ib_mr_memory_pfault_handler(dev, pfault);
1573 break;
1574 default:
1575 mlx5_ib_err(dev, "Invalid page fault event subtype: 0x%x\n",
1576 event_subtype);
1577 mlx5_ib_page_fault_resume(dev, pfault, 1);
1578 }
1579 }
1580
mlx5_ib_eqe_pf_action(struct work_struct * work)1581 static void mlx5_ib_eqe_pf_action(struct work_struct *work)
1582 {
1583 struct mlx5_pagefault *pfault = container_of(work,
1584 struct mlx5_pagefault,
1585 work);
1586 struct mlx5_ib_pf_eq *eq = pfault->eq;
1587
1588 mlx5_ib_pfault(eq->dev, pfault);
1589 mempool_free(pfault, eq->pool);
1590 }
1591
1592 #define MEMORY_SCHEME_PAGE_FAULT_GRANULARITY 4096
mlx5_ib_eq_pf_process(struct mlx5_ib_pf_eq * eq)1593 static void mlx5_ib_eq_pf_process(struct mlx5_ib_pf_eq *eq)
1594 {
1595 struct mlx5_eqe_page_fault *pf_eqe;
1596 struct mlx5_pagefault *pfault;
1597 struct mlx5_eqe *eqe;
1598 int cc = 0;
1599
1600 while ((eqe = mlx5_eq_get_eqe(eq->core, cc))) {
1601 pfault = mempool_alloc(eq->pool, GFP_ATOMIC);
1602 if (!pfault) {
1603 schedule_work(&eq->work);
1604 break;
1605 }
1606
1607 pf_eqe = &eqe->data.page_fault;
1608 pfault->event_subtype = eqe->sub_type;
1609
1610 switch (eqe->sub_type) {
1611 case MLX5_PFAULT_SUBTYPE_RDMA:
1612 /* RDMA based event */
1613 pfault->bytes_committed =
1614 be32_to_cpu(pf_eqe->rdma.bytes_committed);
1615 pfault->type =
1616 be32_to_cpu(pf_eqe->rdma.pftype_token) >> 24;
1617 pfault->token =
1618 be32_to_cpu(pf_eqe->rdma.pftype_token) &
1619 MLX5_24BIT_MASK;
1620 pfault->rdma.r_key =
1621 be32_to_cpu(pf_eqe->rdma.r_key);
1622 pfault->rdma.packet_size =
1623 be16_to_cpu(pf_eqe->rdma.packet_length);
1624 pfault->rdma.rdma_op_len =
1625 be32_to_cpu(pf_eqe->rdma.rdma_op_len);
1626 pfault->rdma.rdma_va =
1627 be64_to_cpu(pf_eqe->rdma.rdma_va);
1628 mlx5_ib_dbg(
1629 eq->dev,
1630 "PAGE_FAULT: subtype: 0x%02x, bytes_committed: 0x%06x, type:0x%x, token: 0x%06llx, r_key: 0x%08x\n",
1631 eqe->sub_type, pfault->bytes_committed,
1632 pfault->type, pfault->token,
1633 pfault->rdma.r_key);
1634 mlx5_ib_dbg(eq->dev,
1635 "PAGE_FAULT: rdma_op_len: 0x%08x, rdma_va: 0x%016llx\n",
1636 pfault->rdma.rdma_op_len,
1637 pfault->rdma.rdma_va);
1638 break;
1639
1640 case MLX5_PFAULT_SUBTYPE_WQE:
1641 /* WQE based event */
1642 pfault->bytes_committed =
1643 be32_to_cpu(pf_eqe->wqe.bytes_committed);
1644 pfault->type =
1645 (be32_to_cpu(pf_eqe->wqe.pftype_wq) >> 24) & 0x7;
1646 pfault->token =
1647 be32_to_cpu(pf_eqe->wqe.token);
1648 pfault->wqe.wq_num =
1649 be32_to_cpu(pf_eqe->wqe.pftype_wq) &
1650 MLX5_24BIT_MASK;
1651 pfault->wqe.wqe_index =
1652 be16_to_cpu(pf_eqe->wqe.wqe_index);
1653 pfault->wqe.packet_size =
1654 be16_to_cpu(pf_eqe->wqe.packet_length);
1655 mlx5_ib_dbg(
1656 eq->dev,
1657 "PAGE_FAULT: subtype: 0x%02x, bytes_committed: 0x%06x, type:0x%x, token: 0x%06llx, wq_num: 0x%06x, wqe_index: 0x%04x\n",
1658 eqe->sub_type, pfault->bytes_committed,
1659 pfault->type, pfault->token, pfault->wqe.wq_num,
1660 pfault->wqe.wqe_index);
1661 break;
1662
1663 case MLX5_PFAULT_SUBTYPE_MEMORY:
1664 /* Memory based event */
1665 pfault->bytes_committed = 0;
1666 pfault->token =
1667 be32_to_cpu(pf_eqe->memory.token31_0) |
1668 ((u64)be16_to_cpu(pf_eqe->memory.token47_32)
1669 << 32);
1670 pfault->memory.va = be64_to_cpu(pf_eqe->memory.va);
1671 pfault->memory.mkey = be32_to_cpu(pf_eqe->memory.mkey);
1672 pfault->memory.fault_byte_count = (be32_to_cpu(
1673 pf_eqe->memory.demand_fault_pages) >> 12) *
1674 MEMORY_SCHEME_PAGE_FAULT_GRANULARITY;
1675 pfault->memory.prefetch_before_byte_count =
1676 be16_to_cpu(
1677 pf_eqe->memory.pre_demand_fault_pages) *
1678 MEMORY_SCHEME_PAGE_FAULT_GRANULARITY;
1679 pfault->memory.prefetch_after_byte_count =
1680 be16_to_cpu(
1681 pf_eqe->memory.post_demand_fault_pages) *
1682 MEMORY_SCHEME_PAGE_FAULT_GRANULARITY;
1683 pfault->memory.flags = pf_eqe->memory.flags;
1684 mlx5_ib_dbg(
1685 eq->dev,
1686 "PAGE_FAULT: subtype: 0x%02x, token: 0x%06llx, mkey: 0x%06x, fault_byte_count: 0x%06x, va: 0x%016llx, flags: 0x%02x\n",
1687 eqe->sub_type, pfault->token,
1688 pfault->memory.mkey,
1689 pfault->memory.fault_byte_count,
1690 pfault->memory.va, pfault->memory.flags);
1691 mlx5_ib_dbg(
1692 eq->dev,
1693 "PAGE_FAULT: prefetch size: before: 0x%06x, after 0x%06x\n",
1694 pfault->memory.prefetch_before_byte_count,
1695 pfault->memory.prefetch_after_byte_count);
1696 break;
1697
1698 default:
1699 mlx5_ib_warn(eq->dev,
1700 "Unsupported page fault event sub-type: 0x%02hhx\n",
1701 eqe->sub_type);
1702 /* Unsupported page faults should still be
1703 * resolved by the page fault handler
1704 */
1705 }
1706
1707 pfault->eq = eq;
1708 INIT_WORK(&pfault->work, mlx5_ib_eqe_pf_action);
1709 queue_work(eq->wq, &pfault->work);
1710
1711 cc = mlx5_eq_update_cc(eq->core, ++cc);
1712 }
1713
1714 mlx5_eq_update_ci(eq->core, cc, 1);
1715 }
1716
mlx5_ib_eq_pf_int(struct notifier_block * nb,unsigned long type,void * data)1717 static int mlx5_ib_eq_pf_int(struct notifier_block *nb, unsigned long type,
1718 void *data)
1719 {
1720 struct mlx5_ib_pf_eq *eq =
1721 container_of(nb, struct mlx5_ib_pf_eq, irq_nb);
1722 unsigned long flags;
1723
1724 if (spin_trylock_irqsave(&eq->lock, flags)) {
1725 mlx5_ib_eq_pf_process(eq);
1726 spin_unlock_irqrestore(&eq->lock, flags);
1727 } else {
1728 schedule_work(&eq->work);
1729 }
1730
1731 return IRQ_HANDLED;
1732 }
1733
1734 /* mempool_refill() was proposed but unfortunately wasn't accepted
1735 * http://lkml.iu.edu/hypermail/linux/kernel/1512.1/05073.html
1736 * Cheap workaround.
1737 */
mempool_refill(mempool_t * pool)1738 static void mempool_refill(mempool_t *pool)
1739 {
1740 while (pool->curr_nr < pool->min_nr)
1741 mempool_free(mempool_alloc(pool, GFP_KERNEL), pool);
1742 }
1743
mlx5_ib_eq_pf_action(struct work_struct * work)1744 static void mlx5_ib_eq_pf_action(struct work_struct *work)
1745 {
1746 struct mlx5_ib_pf_eq *eq =
1747 container_of(work, struct mlx5_ib_pf_eq, work);
1748
1749 mempool_refill(eq->pool);
1750
1751 spin_lock_irq(&eq->lock);
1752 mlx5_ib_eq_pf_process(eq);
1753 spin_unlock_irq(&eq->lock);
1754 }
1755
1756 enum {
1757 MLX5_IB_NUM_PF_EQE = 0x1000,
1758 MLX5_IB_NUM_PF_DRAIN = 64,
1759 };
1760
mlx5r_odp_create_eq(struct mlx5_ib_dev * dev,struct mlx5_ib_pf_eq * eq)1761 int mlx5r_odp_create_eq(struct mlx5_ib_dev *dev, struct mlx5_ib_pf_eq *eq)
1762 {
1763 struct mlx5_eq_param param = {};
1764 int err = 0;
1765
1766 mutex_lock(&dev->odp_eq_mutex);
1767 if (eq->core)
1768 goto unlock;
1769 INIT_WORK(&eq->work, mlx5_ib_eq_pf_action);
1770 spin_lock_init(&eq->lock);
1771 eq->dev = dev;
1772
1773 eq->pool = mempool_create_kmalloc_pool(MLX5_IB_NUM_PF_DRAIN,
1774 sizeof(struct mlx5_pagefault));
1775 if (!eq->pool) {
1776 err = -ENOMEM;
1777 goto unlock;
1778 }
1779
1780 eq->wq = alloc_workqueue("mlx5_ib_page_fault",
1781 WQ_HIGHPRI | WQ_UNBOUND | WQ_MEM_RECLAIM,
1782 MLX5_NUM_CMD_EQE);
1783 if (!eq->wq) {
1784 err = -ENOMEM;
1785 goto err_mempool;
1786 }
1787
1788 eq->irq_nb.notifier_call = mlx5_ib_eq_pf_int;
1789 param = (struct mlx5_eq_param) {
1790 .nent = MLX5_IB_NUM_PF_EQE,
1791 };
1792 param.mask[0] = 1ull << MLX5_EVENT_TYPE_PAGE_FAULT;
1793 eq->core = mlx5_eq_create_generic(dev->mdev, ¶m);
1794 if (IS_ERR(eq->core)) {
1795 err = PTR_ERR(eq->core);
1796 goto err_wq;
1797 }
1798 err = mlx5_eq_enable(dev->mdev, eq->core, &eq->irq_nb);
1799 if (err) {
1800 mlx5_ib_err(dev, "failed to enable odp EQ %d\n", err);
1801 goto err_eq;
1802 }
1803
1804 mutex_unlock(&dev->odp_eq_mutex);
1805 return 0;
1806 err_eq:
1807 mlx5_eq_destroy_generic(dev->mdev, eq->core);
1808 err_wq:
1809 eq->core = NULL;
1810 destroy_workqueue(eq->wq);
1811 err_mempool:
1812 mempool_destroy(eq->pool);
1813 unlock:
1814 mutex_unlock(&dev->odp_eq_mutex);
1815 return err;
1816 }
1817
1818 static int
mlx5_ib_odp_destroy_eq(struct mlx5_ib_dev * dev,struct mlx5_ib_pf_eq * eq)1819 mlx5_ib_odp_destroy_eq(struct mlx5_ib_dev *dev, struct mlx5_ib_pf_eq *eq)
1820 {
1821 int err;
1822
1823 if (!eq->core)
1824 return 0;
1825 mlx5_eq_disable(dev->mdev, eq->core, &eq->irq_nb);
1826 err = mlx5_eq_destroy_generic(dev->mdev, eq->core);
1827 cancel_work_sync(&eq->work);
1828 destroy_workqueue(eq->wq);
1829 mempool_destroy(eq->pool);
1830
1831 return err;
1832 }
1833
mlx5_odp_init_mkey_cache(struct mlx5_ib_dev * dev)1834 int mlx5_odp_init_mkey_cache(struct mlx5_ib_dev *dev)
1835 {
1836 struct mlx5r_cache_rb_key rb_key = {
1837 .access_mode = MLX5_MKC_ACCESS_MODE_KSM,
1838 .ndescs = mlx5_imr_ksm_entries,
1839 };
1840 struct mlx5_cache_ent *ent;
1841
1842 if (!(dev->odp_caps.general_caps & IB_ODP_SUPPORT_IMPLICIT))
1843 return 0;
1844
1845 ent = mlx5r_cache_create_ent_locked(dev, rb_key, true);
1846 if (IS_ERR(ent))
1847 return PTR_ERR(ent);
1848
1849 return 0;
1850 }
1851
1852 static const struct ib_device_ops mlx5_ib_dev_odp_ops = {
1853 .advise_mr = mlx5_ib_advise_mr,
1854 };
1855
mlx5_ib_odp_init_one(struct mlx5_ib_dev * dev)1856 int mlx5_ib_odp_init_one(struct mlx5_ib_dev *dev)
1857 {
1858 internal_fill_odp_caps(dev);
1859
1860 if (!(dev->odp_caps.general_caps & IB_ODP_SUPPORT))
1861 return 0;
1862
1863 ib_set_device_ops(&dev->ib_dev, &mlx5_ib_dev_odp_ops);
1864
1865 mutex_init(&dev->odp_eq_mutex);
1866 return 0;
1867 }
1868
mlx5_ib_odp_cleanup_one(struct mlx5_ib_dev * dev)1869 void mlx5_ib_odp_cleanup_one(struct mlx5_ib_dev *dev)
1870 {
1871 if (!(dev->odp_caps.general_caps & IB_ODP_SUPPORT))
1872 return;
1873
1874 mlx5_ib_odp_destroy_eq(dev, &dev->odp_pf_eq);
1875 }
1876
mlx5_ib_odp_init(void)1877 int mlx5_ib_odp_init(void)
1878 {
1879 mlx5_imr_ksm_entries = BIT_ULL(get_order(TASK_SIZE) -
1880 MLX5_IMR_MTT_BITS);
1881
1882 return 0;
1883 }
1884
1885 struct prefetch_mr_work {
1886 struct work_struct work;
1887 u32 pf_flags;
1888 u32 num_sge;
1889 struct {
1890 u64 io_virt;
1891 struct mlx5_ib_mr *mr;
1892 size_t length;
1893 } frags[];
1894 };
1895
destroy_prefetch_work(struct prefetch_mr_work * work)1896 static void destroy_prefetch_work(struct prefetch_mr_work *work)
1897 {
1898 u32 i;
1899
1900 for (i = 0; i < work->num_sge; ++i)
1901 mlx5r_deref_odp_mkey(&work->frags[i].mr->mmkey);
1902
1903 kvfree(work);
1904 }
1905
1906 static struct mlx5_ib_mr *
get_prefetchable_mr(struct ib_pd * pd,enum ib_uverbs_advise_mr_advice advice,u32 lkey)1907 get_prefetchable_mr(struct ib_pd *pd, enum ib_uverbs_advise_mr_advice advice,
1908 u32 lkey)
1909 {
1910 struct mlx5_ib_dev *dev = to_mdev(pd->device);
1911 struct mlx5_ib_mr *mr = NULL;
1912 struct mlx5_ib_mkey *mmkey;
1913
1914 xa_lock(&dev->odp_mkeys);
1915 mmkey = xa_load(&dev->odp_mkeys, mlx5_base_mkey(lkey));
1916 if (!mmkey || mmkey->key != lkey) {
1917 mr = ERR_PTR(-ENOENT);
1918 goto end;
1919 }
1920 if (mmkey->type != MLX5_MKEY_MR) {
1921 mr = ERR_PTR(-EINVAL);
1922 goto end;
1923 }
1924
1925 mr = container_of(mmkey, struct mlx5_ib_mr, mmkey);
1926
1927 if (mr->ibmr.pd != pd) {
1928 mr = ERR_PTR(-EPERM);
1929 goto end;
1930 }
1931
1932 /* prefetch with write-access must be supported by the MR */
1933 if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE &&
1934 !mr->umem->writable) {
1935 mr = ERR_PTR(-EPERM);
1936 goto end;
1937 }
1938
1939 refcount_inc(&mmkey->usecount);
1940 end:
1941 xa_unlock(&dev->odp_mkeys);
1942 return mr;
1943 }
1944
mlx5_ib_prefetch_mr_work(struct work_struct * w)1945 static void mlx5_ib_prefetch_mr_work(struct work_struct *w)
1946 {
1947 struct prefetch_mr_work *work =
1948 container_of(w, struct prefetch_mr_work, work);
1949 u32 bytes_mapped = 0;
1950 int ret;
1951 u32 i;
1952
1953 /* We rely on IB/core that work is executed if we have num_sge != 0 only. */
1954 WARN_ON(!work->num_sge);
1955 for (i = 0; i < work->num_sge; ++i) {
1956 ret = pagefault_mr(work->frags[i].mr, work->frags[i].io_virt,
1957 work->frags[i].length, &bytes_mapped,
1958 work->pf_flags, false);
1959 if (ret <= 0)
1960 continue;
1961 mlx5_update_odp_stats(work->frags[i].mr, prefetch, ret);
1962 }
1963
1964 destroy_prefetch_work(work);
1965 }
1966
init_prefetch_work(struct ib_pd * pd,enum ib_uverbs_advise_mr_advice advice,u32 pf_flags,struct prefetch_mr_work * work,struct ib_sge * sg_list,u32 num_sge)1967 static int init_prefetch_work(struct ib_pd *pd,
1968 enum ib_uverbs_advise_mr_advice advice,
1969 u32 pf_flags, struct prefetch_mr_work *work,
1970 struct ib_sge *sg_list, u32 num_sge)
1971 {
1972 u32 i;
1973
1974 INIT_WORK(&work->work, mlx5_ib_prefetch_mr_work);
1975 work->pf_flags = pf_flags;
1976
1977 for (i = 0; i < num_sge; ++i) {
1978 struct mlx5_ib_mr *mr;
1979
1980 mr = get_prefetchable_mr(pd, advice, sg_list[i].lkey);
1981 if (IS_ERR(mr)) {
1982 work->num_sge = i;
1983 return PTR_ERR(mr);
1984 }
1985 work->frags[i].io_virt = sg_list[i].addr;
1986 work->frags[i].length = sg_list[i].length;
1987 work->frags[i].mr = mr;
1988 }
1989 work->num_sge = num_sge;
1990 return 0;
1991 }
1992
mlx5_ib_prefetch_sg_list(struct ib_pd * pd,enum ib_uverbs_advise_mr_advice advice,u32 pf_flags,struct ib_sge * sg_list,u32 num_sge)1993 static int mlx5_ib_prefetch_sg_list(struct ib_pd *pd,
1994 enum ib_uverbs_advise_mr_advice advice,
1995 u32 pf_flags, struct ib_sge *sg_list,
1996 u32 num_sge)
1997 {
1998 u32 bytes_mapped = 0;
1999 int ret = 0;
2000 u32 i;
2001
2002 for (i = 0; i < num_sge; ++i) {
2003 struct mlx5_ib_mr *mr;
2004
2005 mr = get_prefetchable_mr(pd, advice, sg_list[i].lkey);
2006 if (IS_ERR(mr))
2007 return PTR_ERR(mr);
2008 ret = pagefault_mr(mr, sg_list[i].addr, sg_list[i].length,
2009 &bytes_mapped, pf_flags, false);
2010 if (ret < 0) {
2011 mlx5r_deref_odp_mkey(&mr->mmkey);
2012 return ret;
2013 }
2014 mlx5_update_odp_stats(mr, prefetch, ret);
2015 mlx5r_deref_odp_mkey(&mr->mmkey);
2016 }
2017
2018 return 0;
2019 }
2020
mlx5_ib_advise_mr_prefetch(struct ib_pd * pd,enum ib_uverbs_advise_mr_advice advice,u32 flags,struct ib_sge * sg_list,u32 num_sge)2021 int mlx5_ib_advise_mr_prefetch(struct ib_pd *pd,
2022 enum ib_uverbs_advise_mr_advice advice,
2023 u32 flags, struct ib_sge *sg_list, u32 num_sge)
2024 {
2025 u32 pf_flags = 0;
2026 struct prefetch_mr_work *work;
2027 int rc;
2028
2029 if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH)
2030 pf_flags |= MLX5_PF_FLAGS_DOWNGRADE;
2031
2032 if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_NO_FAULT)
2033 pf_flags |= MLX5_PF_FLAGS_SNAPSHOT;
2034
2035 if (flags & IB_UVERBS_ADVISE_MR_FLAG_FLUSH)
2036 return mlx5_ib_prefetch_sg_list(pd, advice, pf_flags, sg_list,
2037 num_sge);
2038
2039 work = kvzalloc(struct_size(work, frags, num_sge), GFP_KERNEL);
2040 if (!work)
2041 return -ENOMEM;
2042
2043 rc = init_prefetch_work(pd, advice, pf_flags, work, sg_list, num_sge);
2044 if (rc) {
2045 destroy_prefetch_work(work);
2046 return rc;
2047 }
2048 queue_work(system_unbound_wq, &work->work);
2049 return 0;
2050 }
2051