2 * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
4 * This software is available to you under a choice of one of two
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6 * General Public License (GPL) Version 2, available from the file
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11 * without modification, are permitted provided that the following
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15 * copyright notice, this list of conditions and the following
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23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33 #include <rdma/ib_umem.h>
34 #include <rdma/ib_umem_odp.h>
35 #include <linux/kernel.h>
41 #include <linux/mlx5/eq.h>
43 /* Contains the details of a pagefault. */
44 struct mlx5_pagefault {
50 /* Initiator or send message responder pagefault details. */
52 /* Received packet size, only valid for responders. */
55 * Number of resource holding WQE, depends on type.
59 * WQE index. Refers to either the send queue or
60 * receive queue, according to event_subtype.
64 /* RDMA responder pagefault details */
68 * Received packet size, minimal size page fault
69 * resolution required for forward progress.
77 struct mlx5_ib_pf_eq *eq;
78 struct work_struct work;
81 #define MAX_PREFETCH_LEN (4*1024*1024U)
83 /* Timeout in ms to wait for an active mmu notifier to complete when handling
85 #define MMU_NOTIFIER_TIMEOUT 1000
87 #define MLX5_IMR_MTT_BITS (30 - PAGE_SHIFT)
88 #define MLX5_IMR_MTT_SHIFT (MLX5_IMR_MTT_BITS + PAGE_SHIFT)
89 #define MLX5_IMR_MTT_ENTRIES BIT_ULL(MLX5_IMR_MTT_BITS)
90 #define MLX5_IMR_MTT_SIZE BIT_ULL(MLX5_IMR_MTT_SHIFT)
91 #define MLX5_IMR_MTT_MASK (~(MLX5_IMR_MTT_SIZE - 1))
93 #define MLX5_KSM_PAGE_SHIFT MLX5_IMR_MTT_SHIFT
95 static u64 mlx5_imr_ksm_entries;
97 static void populate_klm(struct mlx5_klm *pklm, size_t idx, size_t nentries,
98 struct mlx5_ib_mr *imr, int flags)
100 struct mlx5_klm *end = pklm + nentries;
102 if (flags & MLX5_IB_UPD_XLT_ZAP) {
103 for (; pklm != end; pklm++, idx++) {
104 pklm->bcount = cpu_to_be32(MLX5_IMR_MTT_SIZE);
105 pklm->key = cpu_to_be32(imr->dev->null_mkey);
112 * The locking here is pretty subtle. Ideally the implicit_children
113 * xarray would be protected by the umem_mutex, however that is not
114 * possible. Instead this uses a weaker update-then-lock pattern:
118 * mutex_lock(umem_mutex)
119 * mlx5_ib_update_xlt()
120 * mutex_unlock(umem_mutex)
123 * ie any change the xarray must be followed by the locked update_xlt
126 * The umem_mutex provides the acquire/release semantic needed to make
127 * the xa_store() visible to a racing thread. While SRCU is not
128 * technically required, using it gives consistent use of the SRCU
129 * locking around the xarray.
131 lockdep_assert_held(&to_ib_umem_odp(imr->umem)->umem_mutex);
132 lockdep_assert_held(&imr->dev->odp_srcu);
134 for (; pklm != end; pklm++, idx++) {
135 struct mlx5_ib_mr *mtt = xa_load(&imr->implicit_children, idx);
137 pklm->bcount = cpu_to_be32(MLX5_IMR_MTT_SIZE);
139 pklm->key = cpu_to_be32(mtt->ibmr.lkey);
140 pklm->va = cpu_to_be64(idx * MLX5_IMR_MTT_SIZE);
142 pklm->key = cpu_to_be32(imr->dev->null_mkey);
148 static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
150 u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
152 if (umem_dma & ODP_READ_ALLOWED_BIT)
153 mtt_entry |= MLX5_IB_MTT_READ;
154 if (umem_dma & ODP_WRITE_ALLOWED_BIT)
155 mtt_entry |= MLX5_IB_MTT_WRITE;
160 static void populate_mtt(__be64 *pas, size_t idx, size_t nentries,
161 struct mlx5_ib_mr *mr, int flags)
163 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
167 if (flags & MLX5_IB_UPD_XLT_ZAP)
170 for (i = 0; i < nentries; i++) {
171 pa = odp->dma_list[idx + i];
172 pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
176 void mlx5_odp_populate_xlt(void *xlt, size_t idx, size_t nentries,
177 struct mlx5_ib_mr *mr, int flags)
179 if (flags & MLX5_IB_UPD_XLT_INDIRECT) {
180 populate_klm(xlt, idx, nentries, mr, flags);
182 populate_mtt(xlt, idx, nentries, mr, flags);
186 static void dma_fence_odp_mr(struct mlx5_ib_mr *mr)
188 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
190 /* Ensure mlx5_ib_invalidate_range() will not touch the MR any more */
191 mutex_lock(&odp->umem_mutex);
193 mlx5_mr_cache_invalidate(mr);
194 ib_umem_odp_unmap_dma_pages(odp, ib_umem_start(odp),
196 WARN_ON(odp->npages);
199 mutex_unlock(&odp->umem_mutex);
201 if (!mr->cache_ent) {
202 mlx5_core_destroy_mkey(mr->dev->mdev, &mr->mmkey);
208 * This must be called after the mr has been removed from implicit_children
209 * and the SRCU synchronized. NOTE: The MR does not necessarily have to be
210 * empty here, parallel page faults could have raced with the free process and
213 static void free_implicit_child_mr(struct mlx5_ib_mr *mr, bool need_imr_xlt)
215 struct mlx5_ib_mr *imr = mr->parent;
216 struct ib_umem_odp *odp_imr = to_ib_umem_odp(imr->umem);
217 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
218 unsigned long idx = ib_umem_start(odp) >> MLX5_IMR_MTT_SHIFT;
221 /* implicit_child_mr's are not allowed to have deferred work */
222 WARN_ON(atomic_read(&mr->num_deferred_work));
225 srcu_key = srcu_read_lock(&mr->dev->odp_srcu);
226 mutex_lock(&odp_imr->umem_mutex);
227 mlx5_ib_update_xlt(mr->parent, idx, 1, 0,
228 MLX5_IB_UPD_XLT_INDIRECT |
229 MLX5_IB_UPD_XLT_ATOMIC);
230 mutex_unlock(&odp_imr->umem_mutex);
231 srcu_read_unlock(&mr->dev->odp_srcu, srcu_key);
234 dma_fence_odp_mr(mr);
237 mlx5_mr_cache_free(mr->dev, mr);
238 ib_umem_odp_release(odp);
239 if (atomic_dec_and_test(&imr->num_deferred_work))
240 wake_up(&imr->q_deferred_work);
243 static void free_implicit_child_mr_work(struct work_struct *work)
245 struct mlx5_ib_mr *mr =
246 container_of(work, struct mlx5_ib_mr, odp_destroy.work);
248 free_implicit_child_mr(mr, true);
251 static void free_implicit_child_mr_rcu(struct rcu_head *head)
253 struct mlx5_ib_mr *mr =
254 container_of(head, struct mlx5_ib_mr, odp_destroy.rcu);
256 /* Freeing a MR is a sleeping operation, so bounce to a work queue */
257 INIT_WORK(&mr->odp_destroy.work, free_implicit_child_mr_work);
258 queue_work(system_unbound_wq, &mr->odp_destroy.work);
261 static void destroy_unused_implicit_child_mr(struct mlx5_ib_mr *mr)
263 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
264 unsigned long idx = ib_umem_start(odp) >> MLX5_IMR_MTT_SHIFT;
265 struct mlx5_ib_mr *imr = mr->parent;
267 xa_lock(&imr->implicit_children);
269 * This can race with mlx5_ib_free_implicit_mr(), the first one to
270 * reach the xa lock wins the race and destroys the MR.
272 if (__xa_cmpxchg(&imr->implicit_children, idx, mr, NULL, GFP_ATOMIC) !=
276 atomic_inc(&imr->num_deferred_work);
277 call_srcu(&mr->dev->odp_srcu, &mr->odp_destroy.rcu,
278 free_implicit_child_mr_rcu);
281 xa_unlock(&imr->implicit_children);
284 static bool mlx5_ib_invalidate_range(struct mmu_interval_notifier *mni,
285 const struct mmu_notifier_range *range,
286 unsigned long cur_seq)
288 struct ib_umem_odp *umem_odp =
289 container_of(mni, struct ib_umem_odp, notifier);
290 struct mlx5_ib_mr *mr;
291 const u64 umr_block_mask = (MLX5_UMR_MTT_ALIGNMENT /
292 sizeof(struct mlx5_mtt)) - 1;
293 u64 idx = 0, blk_start_idx = 0;
294 u64 invalidations = 0;
300 if (!mmu_notifier_range_blockable(range))
303 mutex_lock(&umem_odp->umem_mutex);
304 mmu_interval_set_seq(mni, cur_seq);
306 * If npages is zero then umem_odp->private may not be setup yet. This
307 * does not complete until after the first page is mapped for DMA.
309 if (!umem_odp->npages)
311 mr = umem_odp->private;
313 start = max_t(u64, ib_umem_start(umem_odp), range->start);
314 end = min_t(u64, ib_umem_end(umem_odp), range->end);
317 * Iteration one - zap the HW's MTTs. The notifiers_count ensures that
318 * while we are doing the invalidation, no page fault will attempt to
319 * overwrite the same MTTs. Concurent invalidations might race us,
320 * but they will write 0s as well, so no difference in the end result.
322 for (addr = start; addr < end; addr += BIT(umem_odp->page_shift)) {
323 idx = (addr - ib_umem_start(umem_odp)) >> umem_odp->page_shift;
325 * Strive to write the MTTs in chunks, but avoid overwriting
326 * non-existing MTTs. The huristic here can be improved to
327 * estimate the cost of another UMR vs. the cost of bigger
330 if (umem_odp->dma_list[idx] &
331 (ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT)) {
337 /* Count page invalidations */
338 invalidations += idx - blk_start_idx + 1;
340 u64 umr_offset = idx & umr_block_mask;
342 if (in_block && umr_offset == 0) {
343 mlx5_ib_update_xlt(mr, blk_start_idx,
344 idx - blk_start_idx, 0,
345 MLX5_IB_UPD_XLT_ZAP |
346 MLX5_IB_UPD_XLT_ATOMIC);
352 mlx5_ib_update_xlt(mr, blk_start_idx,
353 idx - blk_start_idx + 1, 0,
354 MLX5_IB_UPD_XLT_ZAP |
355 MLX5_IB_UPD_XLT_ATOMIC);
357 mlx5_update_odp_stats(mr, invalidations, invalidations);
360 * We are now sure that the device will not access the
361 * memory. We can safely unmap it, and mark it as dirty if
365 ib_umem_odp_unmap_dma_pages(umem_odp, start, end);
367 if (unlikely(!umem_odp->npages && mr->parent))
368 destroy_unused_implicit_child_mr(mr);
370 mutex_unlock(&umem_odp->umem_mutex);
374 const struct mmu_interval_notifier_ops mlx5_mn_ops = {
375 .invalidate = mlx5_ib_invalidate_range,
378 void mlx5_ib_internal_fill_odp_caps(struct mlx5_ib_dev *dev)
380 struct ib_odp_caps *caps = &dev->odp_caps;
382 memset(caps, 0, sizeof(*caps));
384 if (!MLX5_CAP_GEN(dev->mdev, pg) ||
385 !mlx5_ib_can_use_umr(dev, true, 0))
388 caps->general_caps = IB_ODP_SUPPORT;
390 if (MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset))
391 dev->odp_max_size = U64_MAX;
393 dev->odp_max_size = BIT_ULL(MLX5_MAX_UMR_SHIFT + PAGE_SHIFT);
395 if (MLX5_CAP_ODP(dev->mdev, ud_odp_caps.send))
396 caps->per_transport_caps.ud_odp_caps |= IB_ODP_SUPPORT_SEND;
398 if (MLX5_CAP_ODP(dev->mdev, ud_odp_caps.srq_receive))
399 caps->per_transport_caps.ud_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
401 if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.send))
402 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_SEND;
404 if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.receive))
405 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_RECV;
407 if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.write))
408 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_WRITE;
410 if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.read))
411 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_READ;
413 if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.atomic))
414 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_ATOMIC;
416 if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.srq_receive))
417 caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
419 if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.send))
420 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_SEND;
422 if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.receive))
423 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_RECV;
425 if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.write))
426 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_WRITE;
428 if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.read))
429 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_READ;
431 if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.atomic))
432 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_ATOMIC;
434 if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.srq_receive))
435 caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
437 if (MLX5_CAP_GEN(dev->mdev, fixed_buffer_size) &&
438 MLX5_CAP_GEN(dev->mdev, null_mkey) &&
439 MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset) &&
440 !MLX5_CAP_GEN(dev->mdev, umr_indirect_mkey_disabled))
441 caps->general_caps |= IB_ODP_SUPPORT_IMPLICIT;
444 static void mlx5_ib_page_fault_resume(struct mlx5_ib_dev *dev,
445 struct mlx5_pagefault *pfault,
448 int wq_num = pfault->event_subtype == MLX5_PFAULT_SUBTYPE_WQE ?
449 pfault->wqe.wq_num : pfault->token;
450 u32 in[MLX5_ST_SZ_DW(page_fault_resume_in)] = {};
453 MLX5_SET(page_fault_resume_in, in, opcode, MLX5_CMD_OP_PAGE_FAULT_RESUME);
454 MLX5_SET(page_fault_resume_in, in, page_fault_type, pfault->type);
455 MLX5_SET(page_fault_resume_in, in, token, pfault->token);
456 MLX5_SET(page_fault_resume_in, in, wq_number, wq_num);
457 MLX5_SET(page_fault_resume_in, in, error, !!error);
459 err = mlx5_cmd_exec_in(dev->mdev, page_fault_resume, in);
461 mlx5_ib_err(dev, "Failed to resolve the page fault on WQ 0x%x err %d\n",
465 static struct mlx5_ib_mr *implicit_get_child_mr(struct mlx5_ib_mr *imr,
468 struct ib_umem_odp *odp;
469 struct mlx5_ib_mr *mr;
470 struct mlx5_ib_mr *ret;
473 odp = ib_umem_odp_alloc_child(to_ib_umem_odp(imr->umem),
474 idx * MLX5_IMR_MTT_SIZE,
475 MLX5_IMR_MTT_SIZE, &mlx5_mn_ops);
477 return ERR_CAST(odp);
479 ret = mr = mlx5_mr_cache_alloc(imr->dev, MLX5_IMR_MTT_CACHE_ENTRY);
483 mr->ibmr.pd = imr->ibmr.pd;
484 mr->access_flags = imr->access_flags;
485 mr->umem = &odp->umem;
486 mr->ibmr.lkey = mr->mmkey.key;
487 mr->ibmr.rkey = mr->mmkey.key;
488 mr->mmkey.iova = idx * MLX5_IMR_MTT_SIZE;
492 err = mlx5_ib_update_xlt(mr, 0,
493 MLX5_IMR_MTT_ENTRIES,
495 MLX5_IB_UPD_XLT_ZAP |
496 MLX5_IB_UPD_XLT_ENABLE);
503 * Once the store to either xarray completes any error unwind has to
504 * use synchronize_srcu(). Avoid this with xa_reserve()
506 ret = xa_cmpxchg(&imr->implicit_children, idx, NULL, mr,
509 if (xa_is_err(ret)) {
510 ret = ERR_PTR(xa_err(ret));
514 * Another thread beat us to creating the child mr, use
520 mlx5_ib_dbg(imr->dev, "key %x mr %p\n", mr->mmkey.key, mr);
524 mlx5_mr_cache_free(imr->dev, mr);
526 ib_umem_odp_release(odp);
530 struct mlx5_ib_mr *mlx5_ib_alloc_implicit_mr(struct mlx5_ib_pd *pd,
531 struct ib_udata *udata,
534 struct mlx5_ib_dev *dev = to_mdev(pd->ibpd.device);
535 struct ib_umem_odp *umem_odp;
536 struct mlx5_ib_mr *imr;
539 umem_odp = ib_umem_odp_alloc_implicit(&dev->ib_dev, access_flags);
540 if (IS_ERR(umem_odp))
541 return ERR_CAST(umem_odp);
543 imr = mlx5_mr_cache_alloc(dev, MLX5_IMR_KSM_CACHE_ENTRY);
549 imr->ibmr.pd = &pd->ibpd;
550 imr->access_flags = access_flags;
552 imr->umem = &umem_odp->umem;
553 imr->ibmr.lkey = imr->mmkey.key;
554 imr->ibmr.rkey = imr->mmkey.key;
555 imr->umem = &umem_odp->umem;
556 imr->is_odp_implicit = true;
557 atomic_set(&imr->num_deferred_work, 0);
558 init_waitqueue_head(&imr->q_deferred_work);
559 xa_init(&imr->implicit_children);
561 err = mlx5_ib_update_xlt(imr, 0,
562 mlx5_imr_ksm_entries,
564 MLX5_IB_UPD_XLT_INDIRECT |
565 MLX5_IB_UPD_XLT_ZAP |
566 MLX5_IB_UPD_XLT_ENABLE);
570 err = xa_err(xa_store(&dev->odp_mkeys, mlx5_base_mkey(imr->mmkey.key),
571 &imr->mmkey, GFP_KERNEL));
575 mlx5_ib_dbg(dev, "key %x mr %p\n", imr->mmkey.key, imr);
578 mlx5_ib_err(dev, "Failed to register MKEY %d\n", err);
579 mlx5_mr_cache_free(dev, imr);
581 ib_umem_odp_release(umem_odp);
585 void mlx5_ib_free_implicit_mr(struct mlx5_ib_mr *imr)
587 struct ib_umem_odp *odp_imr = to_ib_umem_odp(imr->umem);
588 struct mlx5_ib_dev *dev = imr->dev;
589 struct list_head destroy_list;
590 struct mlx5_ib_mr *mtt;
591 struct mlx5_ib_mr *tmp;
594 INIT_LIST_HEAD(&destroy_list);
596 xa_erase(&dev->odp_mkeys, mlx5_base_mkey(imr->mmkey.key));
598 * This stops the SRCU protected page fault path from touching either
599 * the imr or any children. The page fault path can only reach the
600 * children xarray via the imr.
602 synchronize_srcu(&dev->odp_srcu);
605 * All work on the prefetch list must be completed, xa_erase() prevented
606 * new work from being created.
608 wait_event(imr->q_deferred_work, !atomic_read(&imr->num_deferred_work));
611 * At this point it is forbidden for any other thread to enter
612 * pagefault_mr() on this imr. It is already forbidden to call
613 * pagefault_mr() on an implicit child. Due to this additions to
614 * implicit_children are prevented.
618 * Block destroy_unused_implicit_child_mr() from incrementing
621 xa_lock(&imr->implicit_children);
622 xa_for_each (&imr->implicit_children, idx, mtt) {
623 __xa_erase(&imr->implicit_children, idx);
624 list_add(&mtt->odp_destroy.elm, &destroy_list);
626 xa_unlock(&imr->implicit_children);
629 * Wait for any concurrent destroy_unused_implicit_child_mr() to
632 wait_event(imr->q_deferred_work, !atomic_read(&imr->num_deferred_work));
635 * Fence the imr before we destroy the children. This allows us to
636 * skip updating the XLT of the imr during destroy of the child mkey
639 mlx5_mr_cache_invalidate(imr);
641 list_for_each_entry_safe (mtt, tmp, &destroy_list, odp_destroy.elm)
642 free_implicit_child_mr(mtt, false);
644 mlx5_mr_cache_free(dev, imr);
645 ib_umem_odp_release(odp_imr);
649 * mlx5_ib_fence_odp_mr - Stop all access to the ODP MR
652 * On return no parallel threads will be touching this MR and no DMA will be
655 void mlx5_ib_fence_odp_mr(struct mlx5_ib_mr *mr)
657 /* Prevent new page faults and prefetch requests from succeeding */
658 xa_erase(&mr->dev->odp_mkeys, mlx5_base_mkey(mr->mmkey.key));
660 /* Wait for all running page-fault handlers to finish. */
661 synchronize_srcu(&mr->dev->odp_srcu);
663 wait_event(mr->q_deferred_work, !atomic_read(&mr->num_deferred_work));
665 dma_fence_odp_mr(mr);
668 #define MLX5_PF_FLAGS_DOWNGRADE BIT(1)
669 static int pagefault_real_mr(struct mlx5_ib_mr *mr, struct ib_umem_odp *odp,
670 u64 user_va, size_t bcnt, u32 *bytes_mapped,
673 int page_shift, ret, np;
674 bool downgrade = flags & MLX5_PF_FLAGS_DOWNGRADE;
675 unsigned long current_seq;
679 page_shift = odp->page_shift;
680 start_idx = (user_va - ib_umem_start(odp)) >> page_shift;
681 access_mask = ODP_READ_ALLOWED_BIT;
683 if (odp->umem.writable && !downgrade)
684 access_mask |= ODP_WRITE_ALLOWED_BIT;
686 current_seq = mmu_interval_read_begin(&odp->notifier);
688 np = ib_umem_odp_map_dma_pages(odp, user_va, bcnt, access_mask,
693 mutex_lock(&odp->umem_mutex);
694 if (!mmu_interval_read_retry(&odp->notifier, current_seq)) {
696 * No need to check whether the MTTs really belong to
697 * this MR, since ib_umem_odp_map_dma_pages already
700 ret = mlx5_ib_update_xlt(mr, start_idx, np,
701 page_shift, MLX5_IB_UPD_XLT_ATOMIC);
705 mutex_unlock(&odp->umem_mutex);
710 "Failed to update mkey page tables\n");
715 u32 new_mappings = (np << page_shift) -
716 (user_va - round_down(user_va, 1 << page_shift));
718 *bytes_mapped += min_t(u32, new_mappings, bcnt);
721 return np << (page_shift - PAGE_SHIFT);
727 static int pagefault_implicit_mr(struct mlx5_ib_mr *imr,
728 struct ib_umem_odp *odp_imr, u64 user_va,
729 size_t bcnt, u32 *bytes_mapped, u32 flags)
731 unsigned long end_idx = (user_va + bcnt - 1) >> MLX5_IMR_MTT_SHIFT;
732 unsigned long upd_start_idx = end_idx + 1;
733 unsigned long upd_len = 0;
734 unsigned long npages = 0;
738 if (unlikely(user_va >= mlx5_imr_ksm_entries * MLX5_IMR_MTT_SIZE ||
739 mlx5_imr_ksm_entries * MLX5_IMR_MTT_SIZE - user_va < bcnt))
742 /* Fault each child mr that intersects with our interval. */
744 unsigned long idx = user_va >> MLX5_IMR_MTT_SHIFT;
745 struct ib_umem_odp *umem_odp;
746 struct mlx5_ib_mr *mtt;
749 mtt = xa_load(&imr->implicit_children, idx);
750 if (unlikely(!mtt)) {
751 mtt = implicit_get_child_mr(imr, idx);
756 upd_start_idx = min(upd_start_idx, idx);
757 upd_len = idx - upd_start_idx + 1;
760 umem_odp = to_ib_umem_odp(mtt->umem);
761 len = min_t(u64, user_va + bcnt, ib_umem_end(umem_odp)) -
764 ret = pagefault_real_mr(mtt, umem_odp, user_va, len,
765 bytes_mapped, flags);
776 * Any time the implicit_children are changed we must perform an
777 * update of the xlt before exiting to ensure the HW and the
778 * implicit_children remains synchronized.
781 if (likely(!upd_len))
785 * Notice this is not strictly ordered right, the KSM is updated after
786 * the implicit_children is updated, so a parallel page fault could
787 * see a MR that is not yet visible in the KSM. This is similar to a
788 * parallel page fault seeing a MR that is being concurrently removed
789 * from the KSM. Both of these improbable situations are resolved
790 * safely by resuming the HW and then taking another page fault. The
791 * next pagefault handler will see the new information.
793 mutex_lock(&odp_imr->umem_mutex);
794 err = mlx5_ib_update_xlt(imr, upd_start_idx, upd_len, 0,
795 MLX5_IB_UPD_XLT_INDIRECT |
796 MLX5_IB_UPD_XLT_ATOMIC);
797 mutex_unlock(&odp_imr->umem_mutex);
799 mlx5_ib_err(imr->dev, "Failed to update PAS\n");
807 * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are
808 * not accessible, or the MR is no longer valid.
809 * -EAGAIN/-ENOMEM: The operation should be retried
811 * -EINVAL/others: General internal malfunction
812 * >0: Number of pages mapped
814 static int pagefault_mr(struct mlx5_ib_mr *mr, u64 io_virt, size_t bcnt,
815 u32 *bytes_mapped, u32 flags)
817 struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
819 lockdep_assert_held(&mr->dev->odp_srcu);
820 if (unlikely(io_virt < mr->mmkey.iova))
823 if (!odp->is_implicit_odp) {
826 if (check_add_overflow(io_virt - mr->mmkey.iova,
827 (u64)odp->umem.address, &user_va))
829 if (unlikely(user_va >= ib_umem_end(odp) ||
830 ib_umem_end(odp) - user_va < bcnt))
832 return pagefault_real_mr(mr, odp, user_va, bcnt, bytes_mapped,
835 return pagefault_implicit_mr(mr, odp, io_virt, bcnt, bytes_mapped,
840 struct pf_frame *next;
847 static bool mkey_is_eq(struct mlx5_core_mkey *mmkey, u32 key)
851 if (mmkey->type == MLX5_MKEY_MW)
852 return mlx5_base_mkey(mmkey->key) == mlx5_base_mkey(key);
853 return mmkey->key == key;
856 static int get_indirect_num_descs(struct mlx5_core_mkey *mmkey)
858 struct mlx5_ib_mw *mw;
859 struct mlx5_ib_devx_mr *devx_mr;
861 if (mmkey->type == MLX5_MKEY_MW) {
862 mw = container_of(mmkey, struct mlx5_ib_mw, mmkey);
866 devx_mr = container_of(mmkey, struct mlx5_ib_devx_mr,
868 return devx_mr->ndescs;
872 * Handle a single data segment in a page-fault WQE or RDMA region.
874 * Returns number of OS pages retrieved on success. The caller may continue to
875 * the next data segment.
876 * Can return the following error codes:
877 * -EAGAIN to designate a temporary error. The caller will abort handling the
878 * page fault and resolve it.
879 * -EFAULT when there's an error mapping the requested pages. The caller will
880 * abort the page fault handling.
882 static int pagefault_single_data_segment(struct mlx5_ib_dev *dev,
883 struct ib_pd *pd, u32 key,
884 u64 io_virt, size_t bcnt,
885 u32 *bytes_committed,
888 int npages = 0, srcu_key, ret, i, outlen, cur_outlen = 0, depth = 0;
889 struct pf_frame *head = NULL, *frame;
890 struct mlx5_core_mkey *mmkey;
891 struct mlx5_ib_mr *mr;
892 struct mlx5_klm *pklm;
897 srcu_key = srcu_read_lock(&dev->odp_srcu);
899 io_virt += *bytes_committed;
900 bcnt -= *bytes_committed;
903 mmkey = xa_load(&dev->odp_mkeys, mlx5_base_mkey(key));
907 "skipping non ODP MR (lkey=0x%06x) in page fault handler.\n",
910 *bytes_mapped += bcnt;
912 * The user could specify a SGL with multiple lkeys and only
913 * some of them are ODP. Treat the non-ODP ones as fully
919 if (!mkey_is_eq(mmkey, key)) {
920 mlx5_ib_dbg(dev, "failed to find mkey %x\n", key);
925 switch (mmkey->type) {
927 mr = container_of(mmkey, struct mlx5_ib_mr, mmkey);
929 ret = pagefault_mr(mr, io_virt, bcnt, bytes_mapped, 0);
933 mlx5_update_odp_stats(mr, faults, ret);
940 case MLX5_MKEY_INDIRECT_DEVX:
941 ndescs = get_indirect_num_descs(mmkey);
943 if (depth >= MLX5_CAP_GEN(dev->mdev, max_indirection)) {
944 mlx5_ib_dbg(dev, "indirection level exceeded\n");
949 outlen = MLX5_ST_SZ_BYTES(query_mkey_out) +
950 sizeof(*pklm) * (ndescs - 2);
952 if (outlen > cur_outlen) {
954 out = kzalloc(outlen, GFP_KERNEL);
962 pklm = (struct mlx5_klm *)MLX5_ADDR_OF(query_mkey_out, out,
963 bsf0_klm0_pas_mtt0_1);
965 ret = mlx5_core_query_mkey(dev->mdev, mmkey, out, outlen);
969 offset = io_virt - MLX5_GET64(query_mkey_out, out,
970 memory_key_mkey_entry.start_addr);
972 for (i = 0; bcnt && i < ndescs; i++, pklm++) {
973 if (offset >= be32_to_cpu(pklm->bcount)) {
974 offset -= be32_to_cpu(pklm->bcount);
978 frame = kzalloc(sizeof(*frame), GFP_KERNEL);
984 frame->key = be32_to_cpu(pklm->key);
985 frame->io_virt = be64_to_cpu(pklm->va) + offset;
986 frame->bcnt = min_t(size_t, bcnt,
987 be32_to_cpu(pklm->bcount) - offset);
988 frame->depth = depth + 1;
998 mlx5_ib_dbg(dev, "wrong mkey type %d\n", mmkey->type);
1008 io_virt = frame->io_virt;
1010 depth = frame->depth;
1024 srcu_read_unlock(&dev->odp_srcu, srcu_key);
1025 *bytes_committed = 0;
1026 return ret ? ret : npages;
1030 * Parse a series of data segments for page fault handling.
1032 * @pfault contains page fault information.
1033 * @wqe points at the first data segment in the WQE.
1034 * @wqe_end points after the end of the WQE.
1035 * @bytes_mapped receives the number of bytes that the function was able to
1036 * map. This allows the caller to decide intelligently whether
1037 * enough memory was mapped to resolve the page fault
1038 * successfully (e.g. enough for the next MTU, or the entire
1040 * @total_wqe_bytes receives the total data size of this WQE in bytes (minus
1041 * the committed bytes).
1043 * Returns the number of pages loaded if positive, zero for an empty WQE, or a
1044 * negative error code.
1046 static int pagefault_data_segments(struct mlx5_ib_dev *dev,
1047 struct mlx5_pagefault *pfault,
1049 void *wqe_end, u32 *bytes_mapped,
1050 u32 *total_wqe_bytes, bool receive_queue)
1052 int ret = 0, npages = 0;
1061 if (total_wqe_bytes)
1062 *total_wqe_bytes = 0;
1064 while (wqe < wqe_end) {
1065 struct mlx5_wqe_data_seg *dseg = wqe;
1067 io_virt = be64_to_cpu(dseg->addr);
1068 key = be32_to_cpu(dseg->lkey);
1069 byte_count = be32_to_cpu(dseg->byte_count);
1070 inline_segment = !!(byte_count & MLX5_INLINE_SEG);
1071 bcnt = byte_count & ~MLX5_INLINE_SEG;
1073 if (inline_segment) {
1074 bcnt = bcnt & MLX5_WQE_INLINE_SEG_BYTE_COUNT_MASK;
1075 wqe += ALIGN(sizeof(struct mlx5_wqe_inline_seg) + bcnt,
1078 wqe += sizeof(*dseg);
1081 /* receive WQE end of sg list. */
1082 if (receive_queue && bcnt == 0 && key == MLX5_INVALID_LKEY &&
1086 if (!inline_segment && total_wqe_bytes) {
1087 *total_wqe_bytes += bcnt - min_t(size_t, bcnt,
1088 pfault->bytes_committed);
1091 /* A zero length data segment designates a length of 2GB. */
1095 if (inline_segment || bcnt <= pfault->bytes_committed) {
1096 pfault->bytes_committed -=
1098 pfault->bytes_committed);
1102 ret = pagefault_single_data_segment(dev, NULL, key,
1104 &pfault->bytes_committed,
1111 return ret < 0 ? ret : npages;
1115 * Parse initiator WQE. Advances the wqe pointer to point at the
1116 * scatter-gather list, and set wqe_end to the end of the WQE.
1118 static int mlx5_ib_mr_initiator_pfault_handler(
1119 struct mlx5_ib_dev *dev, struct mlx5_pagefault *pfault,
1120 struct mlx5_ib_qp *qp, void **wqe, void **wqe_end, int wqe_length)
1122 struct mlx5_wqe_ctrl_seg *ctrl = *wqe;
1123 u16 wqe_index = pfault->wqe.wqe_index;
1124 struct mlx5_base_av *av;
1125 unsigned ds, opcode;
1126 u32 qpn = qp->trans_qp.base.mqp.qpn;
1128 ds = be32_to_cpu(ctrl->qpn_ds) & MLX5_WQE_CTRL_DS_MASK;
1129 if (ds * MLX5_WQE_DS_UNITS > wqe_length) {
1130 mlx5_ib_err(dev, "Unable to read the complete WQE. ds = 0x%x, ret = 0x%x\n",
1136 mlx5_ib_err(dev, "Got WQE with zero DS. wqe_index=%x, qpn=%x\n",
1141 *wqe_end = *wqe + ds * MLX5_WQE_DS_UNITS;
1142 *wqe += sizeof(*ctrl);
1144 opcode = be32_to_cpu(ctrl->opmod_idx_opcode) &
1145 MLX5_WQE_CTRL_OPCODE_MASK;
1147 if (qp->ibqp.qp_type == IB_QPT_XRC_INI)
1148 *wqe += sizeof(struct mlx5_wqe_xrc_seg);
1150 if (qp->type == IB_QPT_UD || qp->type == MLX5_IB_QPT_DCI) {
1152 if (av->dqp_dct & cpu_to_be32(MLX5_EXTENDED_UD_AV))
1153 *wqe += sizeof(struct mlx5_av);
1155 *wqe += sizeof(struct mlx5_base_av);
1159 case MLX5_OPCODE_RDMA_WRITE:
1160 case MLX5_OPCODE_RDMA_WRITE_IMM:
1161 case MLX5_OPCODE_RDMA_READ:
1162 *wqe += sizeof(struct mlx5_wqe_raddr_seg);
1164 case MLX5_OPCODE_ATOMIC_CS:
1165 case MLX5_OPCODE_ATOMIC_FA:
1166 *wqe += sizeof(struct mlx5_wqe_raddr_seg);
1167 *wqe += sizeof(struct mlx5_wqe_atomic_seg);
1175 * Parse responder WQE and set wqe_end to the end of the WQE.
1177 static int mlx5_ib_mr_responder_pfault_handler_srq(struct mlx5_ib_dev *dev,
1178 struct mlx5_ib_srq *srq,
1179 void **wqe, void **wqe_end,
1182 int wqe_size = 1 << srq->msrq.wqe_shift;
1184 if (wqe_size > wqe_length) {
1185 mlx5_ib_err(dev, "Couldn't read all of the receive WQE's content\n");
1189 *wqe_end = *wqe + wqe_size;
1190 *wqe += sizeof(struct mlx5_wqe_srq_next_seg);
1195 static int mlx5_ib_mr_responder_pfault_handler_rq(struct mlx5_ib_dev *dev,
1196 struct mlx5_ib_qp *qp,
1197 void *wqe, void **wqe_end,
1200 struct mlx5_ib_wq *wq = &qp->rq;
1201 int wqe_size = 1 << wq->wqe_shift;
1203 if (qp->flags_en & MLX5_QP_FLAG_SIGNATURE) {
1204 mlx5_ib_err(dev, "ODP fault with WQE signatures is not supported\n");
1208 if (wqe_size > wqe_length) {
1209 mlx5_ib_err(dev, "Couldn't read all of the receive WQE's content\n");
1213 *wqe_end = wqe + wqe_size;
1218 static inline struct mlx5_core_rsc_common *odp_get_rsc(struct mlx5_ib_dev *dev,
1219 u32 wq_num, int pf_type)
1221 struct mlx5_core_rsc_common *common = NULL;
1222 struct mlx5_core_srq *srq;
1225 case MLX5_WQE_PF_TYPE_RMP:
1226 srq = mlx5_cmd_get_srq(dev, wq_num);
1228 common = &srq->common;
1230 case MLX5_WQE_PF_TYPE_REQ_SEND_OR_WRITE:
1231 case MLX5_WQE_PF_TYPE_RESP:
1232 case MLX5_WQE_PF_TYPE_REQ_READ_OR_ATOMIC:
1233 common = mlx5_core_res_hold(dev, wq_num, MLX5_RES_QP);
1242 static inline struct mlx5_ib_qp *res_to_qp(struct mlx5_core_rsc_common *res)
1244 struct mlx5_core_qp *mqp = (struct mlx5_core_qp *)res;
1246 return to_mibqp(mqp);
1249 static inline struct mlx5_ib_srq *res_to_srq(struct mlx5_core_rsc_common *res)
1251 struct mlx5_core_srq *msrq =
1252 container_of(res, struct mlx5_core_srq, common);
1254 return to_mibsrq(msrq);
1257 static void mlx5_ib_mr_wqe_pfault_handler(struct mlx5_ib_dev *dev,
1258 struct mlx5_pagefault *pfault)
1260 bool sq = pfault->type & MLX5_PFAULT_REQUESTOR;
1261 u16 wqe_index = pfault->wqe.wqe_index;
1262 void *wqe, *wqe_start = NULL, *wqe_end = NULL;
1263 u32 bytes_mapped, total_wqe_bytes;
1264 struct mlx5_core_rsc_common *res;
1265 int resume_with_error = 1;
1266 struct mlx5_ib_qp *qp;
1267 size_t bytes_copied;
1270 res = odp_get_rsc(dev, pfault->wqe.wq_num, pfault->type);
1272 mlx5_ib_dbg(dev, "wqe page fault for missing resource %d\n", pfault->wqe.wq_num);
1276 if (res->res != MLX5_RES_QP && res->res != MLX5_RES_SRQ &&
1277 res->res != MLX5_RES_XSRQ) {
1278 mlx5_ib_err(dev, "wqe page fault for unsupported type %d\n",
1280 goto resolve_page_fault;
1283 wqe_start = (void *)__get_free_page(GFP_KERNEL);
1285 mlx5_ib_err(dev, "Error allocating memory for IO page fault handling.\n");
1286 goto resolve_page_fault;
1290 qp = (res->res == MLX5_RES_QP) ? res_to_qp(res) : NULL;
1292 ret = mlx5_ib_read_wqe_sq(qp, wqe_index, wqe, PAGE_SIZE,
1296 ret = mlx5_ib_mr_initiator_pfault_handler(
1297 dev, pfault, qp, &wqe, &wqe_end, bytes_copied);
1298 } else if (qp && !sq) {
1299 ret = mlx5_ib_read_wqe_rq(qp, wqe_index, wqe, PAGE_SIZE,
1303 ret = mlx5_ib_mr_responder_pfault_handler_rq(
1304 dev, qp, wqe, &wqe_end, bytes_copied);
1306 struct mlx5_ib_srq *srq = res_to_srq(res);
1308 ret = mlx5_ib_read_wqe_srq(srq, wqe_index, wqe, PAGE_SIZE,
1312 ret = mlx5_ib_mr_responder_pfault_handler_srq(
1313 dev, srq, &wqe, &wqe_end, bytes_copied);
1316 if (ret < 0 || wqe >= wqe_end)
1317 goto resolve_page_fault;
1319 ret = pagefault_data_segments(dev, pfault, wqe, wqe_end, &bytes_mapped,
1320 &total_wqe_bytes, !sq);
1324 if (ret < 0 || total_wqe_bytes > bytes_mapped)
1325 goto resolve_page_fault;
1329 resume_with_error = 0;
1335 "Failed reading a WQE following page fault, error %d, wqe_index %x, qpn %x\n",
1336 ret, wqe_index, pfault->token);
1339 mlx5_ib_page_fault_resume(dev, pfault, resume_with_error);
1340 mlx5_ib_dbg(dev, "PAGE FAULT completed. QP 0x%x resume_with_error=%d, type: 0x%x\n",
1341 pfault->wqe.wq_num, resume_with_error,
1343 mlx5_core_res_put(res);
1344 free_page((unsigned long)wqe_start);
1347 static int pages_in_range(u64 address, u32 length)
1349 return (ALIGN(address + length, PAGE_SIZE) -
1350 (address & PAGE_MASK)) >> PAGE_SHIFT;
1353 static void mlx5_ib_mr_rdma_pfault_handler(struct mlx5_ib_dev *dev,
1354 struct mlx5_pagefault *pfault)
1358 u32 prefetch_len = pfault->bytes_committed;
1359 int prefetch_activated = 0;
1360 u32 rkey = pfault->rdma.r_key;
1363 /* The RDMA responder handler handles the page fault in two parts.
1364 * First it brings the necessary pages for the current packet
1365 * (and uses the pfault context), and then (after resuming the QP)
1366 * prefetches more pages. The second operation cannot use the pfault
1367 * context and therefore uses the dummy_pfault context allocated on
1369 pfault->rdma.rdma_va += pfault->bytes_committed;
1370 pfault->rdma.rdma_op_len -= min(pfault->bytes_committed,
1371 pfault->rdma.rdma_op_len);
1372 pfault->bytes_committed = 0;
1374 address = pfault->rdma.rdma_va;
1375 length = pfault->rdma.rdma_op_len;
1377 /* For some operations, the hardware cannot tell the exact message
1378 * length, and in those cases it reports zero. Use prefetch
1381 prefetch_activated = 1;
1382 length = pfault->rdma.packet_size;
1383 prefetch_len = min(MAX_PREFETCH_LEN, prefetch_len);
1386 ret = pagefault_single_data_segment(dev, NULL, rkey, address, length,
1387 &pfault->bytes_committed, NULL);
1388 if (ret == -EAGAIN) {
1389 /* We're racing with an invalidation, don't prefetch */
1390 prefetch_activated = 0;
1391 } else if (ret < 0 || pages_in_range(address, length) > ret) {
1392 mlx5_ib_page_fault_resume(dev, pfault, 1);
1394 mlx5_ib_dbg(dev, "PAGE FAULT error %d. QP 0x%x, type: 0x%x\n",
1395 ret, pfault->token, pfault->type);
1399 mlx5_ib_page_fault_resume(dev, pfault, 0);
1400 mlx5_ib_dbg(dev, "PAGE FAULT completed. QP 0x%x, type: 0x%x, prefetch_activated: %d\n",
1401 pfault->token, pfault->type,
1402 prefetch_activated);
1404 /* At this point, there might be a new pagefault already arriving in
1405 * the eq, switch to the dummy pagefault for the rest of the
1406 * processing. We're still OK with the objects being alive as the
1407 * work-queue is being fenced. */
1409 if (prefetch_activated) {
1410 u32 bytes_committed = 0;
1412 ret = pagefault_single_data_segment(dev, NULL, rkey, address,
1414 &bytes_committed, NULL);
1415 if (ret < 0 && ret != -EAGAIN) {
1416 mlx5_ib_dbg(dev, "Prefetch failed. ret: %d, QP 0x%x, address: 0x%.16llx, length = 0x%.16x\n",
1417 ret, pfault->token, address, prefetch_len);
1422 static void mlx5_ib_pfault(struct mlx5_ib_dev *dev, struct mlx5_pagefault *pfault)
1424 u8 event_subtype = pfault->event_subtype;
1426 switch (event_subtype) {
1427 case MLX5_PFAULT_SUBTYPE_WQE:
1428 mlx5_ib_mr_wqe_pfault_handler(dev, pfault);
1430 case MLX5_PFAULT_SUBTYPE_RDMA:
1431 mlx5_ib_mr_rdma_pfault_handler(dev, pfault);
1434 mlx5_ib_err(dev, "Invalid page fault event subtype: 0x%x\n",
1436 mlx5_ib_page_fault_resume(dev, pfault, 1);
1440 static void mlx5_ib_eqe_pf_action(struct work_struct *work)
1442 struct mlx5_pagefault *pfault = container_of(work,
1443 struct mlx5_pagefault,
1445 struct mlx5_ib_pf_eq *eq = pfault->eq;
1447 mlx5_ib_pfault(eq->dev, pfault);
1448 mempool_free(pfault, eq->pool);
1451 static void mlx5_ib_eq_pf_process(struct mlx5_ib_pf_eq *eq)
1453 struct mlx5_eqe_page_fault *pf_eqe;
1454 struct mlx5_pagefault *pfault;
1455 struct mlx5_eqe *eqe;
1458 while ((eqe = mlx5_eq_get_eqe(eq->core, cc))) {
1459 pfault = mempool_alloc(eq->pool, GFP_ATOMIC);
1461 schedule_work(&eq->work);
1465 pf_eqe = &eqe->data.page_fault;
1466 pfault->event_subtype = eqe->sub_type;
1467 pfault->bytes_committed = be32_to_cpu(pf_eqe->bytes_committed);
1469 mlx5_ib_dbg(eq->dev,
1470 "PAGE_FAULT: subtype: 0x%02x, bytes_committed: 0x%06x\n",
1471 eqe->sub_type, pfault->bytes_committed);
1473 switch (eqe->sub_type) {
1474 case MLX5_PFAULT_SUBTYPE_RDMA:
1475 /* RDMA based event */
1477 be32_to_cpu(pf_eqe->rdma.pftype_token) >> 24;
1479 be32_to_cpu(pf_eqe->rdma.pftype_token) &
1481 pfault->rdma.r_key =
1482 be32_to_cpu(pf_eqe->rdma.r_key);
1483 pfault->rdma.packet_size =
1484 be16_to_cpu(pf_eqe->rdma.packet_length);
1485 pfault->rdma.rdma_op_len =
1486 be32_to_cpu(pf_eqe->rdma.rdma_op_len);
1487 pfault->rdma.rdma_va =
1488 be64_to_cpu(pf_eqe->rdma.rdma_va);
1489 mlx5_ib_dbg(eq->dev,
1490 "PAGE_FAULT: type:0x%x, token: 0x%06x, r_key: 0x%08x\n",
1491 pfault->type, pfault->token,
1492 pfault->rdma.r_key);
1493 mlx5_ib_dbg(eq->dev,
1494 "PAGE_FAULT: rdma_op_len: 0x%08x, rdma_va: 0x%016llx\n",
1495 pfault->rdma.rdma_op_len,
1496 pfault->rdma.rdma_va);
1499 case MLX5_PFAULT_SUBTYPE_WQE:
1500 /* WQE based event */
1502 (be32_to_cpu(pf_eqe->wqe.pftype_wq) >> 24) & 0x7;
1504 be32_to_cpu(pf_eqe->wqe.token);
1505 pfault->wqe.wq_num =
1506 be32_to_cpu(pf_eqe->wqe.pftype_wq) &
1508 pfault->wqe.wqe_index =
1509 be16_to_cpu(pf_eqe->wqe.wqe_index);
1510 pfault->wqe.packet_size =
1511 be16_to_cpu(pf_eqe->wqe.packet_length);
1512 mlx5_ib_dbg(eq->dev,
1513 "PAGE_FAULT: type:0x%x, token: 0x%06x, wq_num: 0x%06x, wqe_index: 0x%04x\n",
1514 pfault->type, pfault->token,
1516 pfault->wqe.wqe_index);
1520 mlx5_ib_warn(eq->dev,
1521 "Unsupported page fault event sub-type: 0x%02hhx\n",
1523 /* Unsupported page faults should still be
1524 * resolved by the page fault handler
1529 INIT_WORK(&pfault->work, mlx5_ib_eqe_pf_action);
1530 queue_work(eq->wq, &pfault->work);
1532 cc = mlx5_eq_update_cc(eq->core, ++cc);
1535 mlx5_eq_update_ci(eq->core, cc, 1);
1538 static int mlx5_ib_eq_pf_int(struct notifier_block *nb, unsigned long type,
1541 struct mlx5_ib_pf_eq *eq =
1542 container_of(nb, struct mlx5_ib_pf_eq, irq_nb);
1543 unsigned long flags;
1545 if (spin_trylock_irqsave(&eq->lock, flags)) {
1546 mlx5_ib_eq_pf_process(eq);
1547 spin_unlock_irqrestore(&eq->lock, flags);
1549 schedule_work(&eq->work);
1555 /* mempool_refill() was proposed but unfortunately wasn't accepted
1556 * http://lkml.iu.edu/hypermail/linux/kernel/1512.1/05073.html
1559 static void mempool_refill(mempool_t *pool)
1561 while (pool->curr_nr < pool->min_nr)
1562 mempool_free(mempool_alloc(pool, GFP_KERNEL), pool);
1565 static void mlx5_ib_eq_pf_action(struct work_struct *work)
1567 struct mlx5_ib_pf_eq *eq =
1568 container_of(work, struct mlx5_ib_pf_eq, work);
1570 mempool_refill(eq->pool);
1572 spin_lock_irq(&eq->lock);
1573 mlx5_ib_eq_pf_process(eq);
1574 spin_unlock_irq(&eq->lock);
1578 MLX5_IB_NUM_PF_EQE = 0x1000,
1579 MLX5_IB_NUM_PF_DRAIN = 64,
1583 mlx5_ib_create_pf_eq(struct mlx5_ib_dev *dev, struct mlx5_ib_pf_eq *eq)
1585 struct mlx5_eq_param param = {};
1588 INIT_WORK(&eq->work, mlx5_ib_eq_pf_action);
1589 spin_lock_init(&eq->lock);
1592 eq->pool = mempool_create_kmalloc_pool(MLX5_IB_NUM_PF_DRAIN,
1593 sizeof(struct mlx5_pagefault));
1597 eq->wq = alloc_workqueue("mlx5_ib_page_fault",
1598 WQ_HIGHPRI | WQ_UNBOUND | WQ_MEM_RECLAIM,
1605 eq->irq_nb.notifier_call = mlx5_ib_eq_pf_int;
1606 param = (struct mlx5_eq_param) {
1608 .nent = MLX5_IB_NUM_PF_EQE,
1610 param.mask[0] = 1ull << MLX5_EVENT_TYPE_PAGE_FAULT;
1611 eq->core = mlx5_eq_create_generic(dev->mdev, ¶m);
1612 if (IS_ERR(eq->core)) {
1613 err = PTR_ERR(eq->core);
1616 err = mlx5_eq_enable(dev->mdev, eq->core, &eq->irq_nb);
1618 mlx5_ib_err(dev, "failed to enable odp EQ %d\n", err);
1624 mlx5_eq_destroy_generic(dev->mdev, eq->core);
1626 destroy_workqueue(eq->wq);
1628 mempool_destroy(eq->pool);
1633 mlx5_ib_destroy_pf_eq(struct mlx5_ib_dev *dev, struct mlx5_ib_pf_eq *eq)
1637 mlx5_eq_disable(dev->mdev, eq->core, &eq->irq_nb);
1638 err = mlx5_eq_destroy_generic(dev->mdev, eq->core);
1639 cancel_work_sync(&eq->work);
1640 destroy_workqueue(eq->wq);
1641 mempool_destroy(eq->pool);
1646 void mlx5_odp_init_mr_cache_entry(struct mlx5_cache_ent *ent)
1648 if (!(ent->dev->odp_caps.general_caps & IB_ODP_SUPPORT_IMPLICIT))
1651 switch (ent->order - 2) {
1652 case MLX5_IMR_MTT_CACHE_ENTRY:
1653 ent->page = PAGE_SHIFT;
1654 ent->xlt = MLX5_IMR_MTT_ENTRIES *
1655 sizeof(struct mlx5_mtt) /
1656 MLX5_IB_UMR_OCTOWORD;
1657 ent->access_mode = MLX5_MKC_ACCESS_MODE_MTT;
1661 case MLX5_IMR_KSM_CACHE_ENTRY:
1662 ent->page = MLX5_KSM_PAGE_SHIFT;
1663 ent->xlt = mlx5_imr_ksm_entries *
1664 sizeof(struct mlx5_klm) /
1665 MLX5_IB_UMR_OCTOWORD;
1666 ent->access_mode = MLX5_MKC_ACCESS_MODE_KSM;
1672 static const struct ib_device_ops mlx5_ib_dev_odp_ops = {
1673 .advise_mr = mlx5_ib_advise_mr,
1676 int mlx5_ib_odp_init_one(struct mlx5_ib_dev *dev)
1680 if (!(dev->odp_caps.general_caps & IB_ODP_SUPPORT))
1683 ib_set_device_ops(&dev->ib_dev, &mlx5_ib_dev_odp_ops);
1685 if (dev->odp_caps.general_caps & IB_ODP_SUPPORT_IMPLICIT) {
1686 ret = mlx5_cmd_null_mkey(dev->mdev, &dev->null_mkey);
1688 mlx5_ib_err(dev, "Error getting null_mkey %d\n", ret);
1693 ret = mlx5_ib_create_pf_eq(dev, &dev->odp_pf_eq);
1698 void mlx5_ib_odp_cleanup_one(struct mlx5_ib_dev *dev)
1700 if (!(dev->odp_caps.general_caps & IB_ODP_SUPPORT))
1703 mlx5_ib_destroy_pf_eq(dev, &dev->odp_pf_eq);
1706 int mlx5_ib_odp_init(void)
1708 mlx5_imr_ksm_entries = BIT_ULL(get_order(TASK_SIZE) -
1714 struct prefetch_mr_work {
1715 struct work_struct work;
1720 struct mlx5_ib_mr *mr;
1725 static void destroy_prefetch_work(struct prefetch_mr_work *work)
1729 for (i = 0; i < work->num_sge; ++i)
1730 if (atomic_dec_and_test(&work->frags[i].mr->num_deferred_work))
1731 wake_up(&work->frags[i].mr->q_deferred_work);
1735 static struct mlx5_ib_mr *
1736 get_prefetchable_mr(struct ib_pd *pd, enum ib_uverbs_advise_mr_advice advice,
1739 struct mlx5_ib_dev *dev = to_mdev(pd->device);
1740 struct mlx5_core_mkey *mmkey;
1741 struct ib_umem_odp *odp;
1742 struct mlx5_ib_mr *mr;
1744 lockdep_assert_held(&dev->odp_srcu);
1746 mmkey = xa_load(&dev->odp_mkeys, mlx5_base_mkey(lkey));
1747 if (!mmkey || mmkey->key != lkey || mmkey->type != MLX5_MKEY_MR)
1750 mr = container_of(mmkey, struct mlx5_ib_mr, mmkey);
1752 if (mr->ibmr.pd != pd)
1755 odp = to_ib_umem_odp(mr->umem);
1757 /* prefetch with write-access must be supported by the MR */
1758 if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE &&
1759 !odp->umem.writable)
1765 static void mlx5_ib_prefetch_mr_work(struct work_struct *w)
1767 struct prefetch_mr_work *work =
1768 container_of(w, struct prefetch_mr_work, work);
1769 struct mlx5_ib_dev *dev;
1770 u32 bytes_mapped = 0;
1775 /* We rely on IB/core that work is executed if we have num_sge != 0 only. */
1776 WARN_ON(!work->num_sge);
1777 dev = work->frags[0].mr->dev;
1778 /* SRCU should be held when calling to mlx5_odp_populate_xlt() */
1779 srcu_key = srcu_read_lock(&dev->odp_srcu);
1780 for (i = 0; i < work->num_sge; ++i) {
1781 ret = pagefault_mr(work->frags[i].mr, work->frags[i].io_virt,
1782 work->frags[i].length, &bytes_mapped,
1786 mlx5_update_odp_stats(work->frags[i].mr, prefetch, ret);
1788 srcu_read_unlock(&dev->odp_srcu, srcu_key);
1790 destroy_prefetch_work(work);
1793 static bool init_prefetch_work(struct ib_pd *pd,
1794 enum ib_uverbs_advise_mr_advice advice,
1795 u32 pf_flags, struct prefetch_mr_work *work,
1796 struct ib_sge *sg_list, u32 num_sge)
1800 INIT_WORK(&work->work, mlx5_ib_prefetch_mr_work);
1801 work->pf_flags = pf_flags;
1803 for (i = 0; i < num_sge; ++i) {
1804 work->frags[i].io_virt = sg_list[i].addr;
1805 work->frags[i].length = sg_list[i].length;
1807 get_prefetchable_mr(pd, advice, sg_list[i].lkey);
1808 if (!work->frags[i].mr) {
1813 /* Keep the MR pointer will valid outside the SRCU */
1814 atomic_inc(&work->frags[i].mr->num_deferred_work);
1816 work->num_sge = num_sge;
1820 static int mlx5_ib_prefetch_sg_list(struct ib_pd *pd,
1821 enum ib_uverbs_advise_mr_advice advice,
1822 u32 pf_flags, struct ib_sge *sg_list,
1825 struct mlx5_ib_dev *dev = to_mdev(pd->device);
1826 u32 bytes_mapped = 0;
1831 srcu_key = srcu_read_lock(&dev->odp_srcu);
1832 for (i = 0; i < num_sge; ++i) {
1833 struct mlx5_ib_mr *mr;
1835 mr = get_prefetchable_mr(pd, advice, sg_list[i].lkey);
1840 ret = pagefault_mr(mr, sg_list[i].addr, sg_list[i].length,
1841 &bytes_mapped, pf_flags);
1844 mlx5_update_odp_stats(mr, prefetch, ret);
1849 srcu_read_unlock(&dev->odp_srcu, srcu_key);
1853 int mlx5_ib_advise_mr_prefetch(struct ib_pd *pd,
1854 enum ib_uverbs_advise_mr_advice advice,
1855 u32 flags, struct ib_sge *sg_list, u32 num_sge)
1857 struct mlx5_ib_dev *dev = to_mdev(pd->device);
1859 struct prefetch_mr_work *work;
1862 if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH)
1863 pf_flags |= MLX5_PF_FLAGS_DOWNGRADE;
1865 if (flags & IB_UVERBS_ADVISE_MR_FLAG_FLUSH)
1866 return mlx5_ib_prefetch_sg_list(pd, advice, pf_flags, sg_list,
1869 work = kvzalloc(struct_size(work, frags, num_sge), GFP_KERNEL);
1873 srcu_key = srcu_read_lock(&dev->odp_srcu);
1874 if (!init_prefetch_work(pd, advice, pf_flags, work, sg_list, num_sge)) {
1875 srcu_read_unlock(&dev->odp_srcu, srcu_key);
1876 destroy_prefetch_work(work);
1879 queue_work(system_unbound_wq, &work->work);
1880 srcu_read_unlock(&dev->odp_srcu, srcu_key);