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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/infiniband/hw/mlx5/odp.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/infiniband/hw/mlx5/odp.c')
-rw-r--r--drivers/infiniband/hw/mlx5/odp.c1821
1 files changed, 1821 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c
new file mode 100644
index 000000000..bc9795881
--- /dev/null
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -0,0 +1,1821 @@
+/*
+ * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <rdma/ib_umem_odp.h>
+#include <linux/kernel.h>
+#include <linux/dma-buf.h>
+#include <linux/dma-resv.h>
+
+#include "mlx5_ib.h"
+#include "cmd.h"
+#include "umr.h"
+#include "qp.h"
+
+#include <linux/mlx5/eq.h>
+
+/* Contains the details of a pagefault. */
+struct mlx5_pagefault {
+ u32 bytes_committed;
+ u32 token;
+ u8 event_subtype;
+ u8 type;
+ union {
+ /* Initiator or send message responder pagefault details. */
+ struct {
+ /* Received packet size, only valid for responders. */
+ u32 packet_size;
+ /*
+ * Number of resource holding WQE, depends on type.
+ */
+ u32 wq_num;
+ /*
+ * WQE index. Refers to either the send queue or
+ * receive queue, according to event_subtype.
+ */
+ u16 wqe_index;
+ } wqe;
+ /* RDMA responder pagefault details */
+ struct {
+ u32 r_key;
+ /*
+ * Received packet size, minimal size page fault
+ * resolution required for forward progress.
+ */
+ u32 packet_size;
+ u32 rdma_op_len;
+ u64 rdma_va;
+ } rdma;
+ };
+
+ struct mlx5_ib_pf_eq *eq;
+ struct work_struct work;
+};
+
+#define MAX_PREFETCH_LEN (4*1024*1024U)
+
+/* Timeout in ms to wait for an active mmu notifier to complete when handling
+ * a pagefault. */
+#define MMU_NOTIFIER_TIMEOUT 1000
+
+#define MLX5_IMR_MTT_BITS (30 - PAGE_SHIFT)
+#define MLX5_IMR_MTT_SHIFT (MLX5_IMR_MTT_BITS + PAGE_SHIFT)
+#define MLX5_IMR_MTT_ENTRIES BIT_ULL(MLX5_IMR_MTT_BITS)
+#define MLX5_IMR_MTT_SIZE BIT_ULL(MLX5_IMR_MTT_SHIFT)
+#define MLX5_IMR_MTT_MASK (~(MLX5_IMR_MTT_SIZE - 1))
+
+#define MLX5_KSM_PAGE_SHIFT MLX5_IMR_MTT_SHIFT
+
+static u64 mlx5_imr_ksm_entries;
+
+static void populate_klm(struct mlx5_klm *pklm, size_t idx, size_t nentries,
+ struct mlx5_ib_mr *imr, int flags)
+{
+ struct mlx5_klm *end = pklm + nentries;
+
+ if (flags & MLX5_IB_UPD_XLT_ZAP) {
+ for (; pklm != end; pklm++, idx++) {
+ pklm->bcount = cpu_to_be32(MLX5_IMR_MTT_SIZE);
+ pklm->key = cpu_to_be32(mr_to_mdev(imr)->null_mkey);
+ pklm->va = 0;
+ }
+ return;
+ }
+
+ /*
+ * The locking here is pretty subtle. Ideally the implicit_children
+ * xarray would be protected by the umem_mutex, however that is not
+ * possible. Instead this uses a weaker update-then-lock pattern:
+ *
+ * xa_store()
+ * mutex_lock(umem_mutex)
+ * mlx5r_umr_update_xlt()
+ * mutex_unlock(umem_mutex)
+ * destroy lkey
+ *
+ * ie any change the xarray must be followed by the locked update_xlt
+ * before destroying.
+ *
+ * The umem_mutex provides the acquire/release semantic needed to make
+ * the xa_store() visible to a racing thread.
+ */
+ lockdep_assert_held(&to_ib_umem_odp(imr->umem)->umem_mutex);
+
+ for (; pklm != end; pklm++, idx++) {
+ struct mlx5_ib_mr *mtt = xa_load(&imr->implicit_children, idx);
+
+ pklm->bcount = cpu_to_be32(MLX5_IMR_MTT_SIZE);
+ if (mtt) {
+ pklm->key = cpu_to_be32(mtt->ibmr.lkey);
+ pklm->va = cpu_to_be64(idx * MLX5_IMR_MTT_SIZE);
+ } else {
+ pklm->key = cpu_to_be32(mr_to_mdev(imr)->null_mkey);
+ pklm->va = 0;
+ }
+ }
+}
+
+static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
+{
+ u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
+
+ if (umem_dma & ODP_READ_ALLOWED_BIT)
+ mtt_entry |= MLX5_IB_MTT_READ;
+ if (umem_dma & ODP_WRITE_ALLOWED_BIT)
+ mtt_entry |= MLX5_IB_MTT_WRITE;
+
+ return mtt_entry;
+}
+
+static void populate_mtt(__be64 *pas, size_t idx, size_t nentries,
+ struct mlx5_ib_mr *mr, int flags)
+{
+ struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
+ dma_addr_t pa;
+ size_t i;
+
+ if (flags & MLX5_IB_UPD_XLT_ZAP)
+ return;
+
+ for (i = 0; i < nentries; i++) {
+ pa = odp->dma_list[idx + i];
+ pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
+ }
+}
+
+void mlx5_odp_populate_xlt(void *xlt, size_t idx, size_t nentries,
+ struct mlx5_ib_mr *mr, int flags)
+{
+ if (flags & MLX5_IB_UPD_XLT_INDIRECT) {
+ populate_klm(xlt, idx, nentries, mr, flags);
+ } else {
+ populate_mtt(xlt, idx, nentries, mr, flags);
+ }
+}
+
+/*
+ * This must be called after the mr has been removed from implicit_children.
+ * NOTE: The MR does not necessarily have to be
+ * empty here, parallel page faults could have raced with the free process and
+ * added pages to it.
+ */
+static void free_implicit_child_mr_work(struct work_struct *work)
+{
+ struct mlx5_ib_mr *mr =
+ container_of(work, struct mlx5_ib_mr, odp_destroy.work);
+ struct mlx5_ib_mr *imr = mr->parent;
+ struct ib_umem_odp *odp_imr = to_ib_umem_odp(imr->umem);
+ struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
+
+ mlx5r_deref_wait_odp_mkey(&mr->mmkey);
+
+ mutex_lock(&odp_imr->umem_mutex);
+ mlx5r_umr_update_xlt(mr->parent,
+ ib_umem_start(odp) >> MLX5_IMR_MTT_SHIFT, 1, 0,
+ MLX5_IB_UPD_XLT_INDIRECT | MLX5_IB_UPD_XLT_ATOMIC);
+ mutex_unlock(&odp_imr->umem_mutex);
+ mlx5_ib_dereg_mr(&mr->ibmr, NULL);
+
+ mlx5r_deref_odp_mkey(&imr->mmkey);
+}
+
+static void destroy_unused_implicit_child_mr(struct mlx5_ib_mr *mr)
+{
+ struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
+ unsigned long idx = ib_umem_start(odp) >> MLX5_IMR_MTT_SHIFT;
+ struct mlx5_ib_mr *imr = mr->parent;
+
+ if (!refcount_inc_not_zero(&imr->mmkey.usecount))
+ return;
+
+ xa_erase(&imr->implicit_children, idx);
+
+ /* Freeing a MR is a sleeping operation, so bounce to a work queue */
+ INIT_WORK(&mr->odp_destroy.work, free_implicit_child_mr_work);
+ queue_work(system_unbound_wq, &mr->odp_destroy.work);
+}
+
+static bool mlx5_ib_invalidate_range(struct mmu_interval_notifier *mni,
+ const struct mmu_notifier_range *range,
+ unsigned long cur_seq)
+{
+ struct ib_umem_odp *umem_odp =
+ container_of(mni, struct ib_umem_odp, notifier);
+ struct mlx5_ib_mr *mr;
+ const u64 umr_block_mask = (MLX5_UMR_MTT_ALIGNMENT /
+ sizeof(struct mlx5_mtt)) - 1;
+ u64 idx = 0, blk_start_idx = 0;
+ u64 invalidations = 0;
+ unsigned long start;
+ unsigned long end;
+ int in_block = 0;
+ u64 addr;
+
+ if (!mmu_notifier_range_blockable(range))
+ return false;
+
+ mutex_lock(&umem_odp->umem_mutex);
+ mmu_interval_set_seq(mni, cur_seq);
+ /*
+ * If npages is zero then umem_odp->private may not be setup yet. This
+ * does not complete until after the first page is mapped for DMA.
+ */
+ if (!umem_odp->npages)
+ goto out;
+ mr = umem_odp->private;
+
+ start = max_t(u64, ib_umem_start(umem_odp), range->start);
+ end = min_t(u64, ib_umem_end(umem_odp), range->end);
+
+ /*
+ * Iteration one - zap the HW's MTTs. The notifiers_count ensures that
+ * while we are doing the invalidation, no page fault will attempt to
+ * overwrite the same MTTs. Concurent invalidations might race us,
+ * but they will write 0s as well, so no difference in the end result.
+ */
+ for (addr = start; addr < end; addr += BIT(umem_odp->page_shift)) {
+ idx = (addr - ib_umem_start(umem_odp)) >> umem_odp->page_shift;
+ /*
+ * Strive to write the MTTs in chunks, but avoid overwriting
+ * non-existing MTTs. The huristic here can be improved to
+ * estimate the cost of another UMR vs. the cost of bigger
+ * UMR.
+ */
+ if (umem_odp->dma_list[idx] &
+ (ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT)) {
+ if (!in_block) {
+ blk_start_idx = idx;
+ in_block = 1;
+ }
+
+ /* Count page invalidations */
+ invalidations += idx - blk_start_idx + 1;
+ } else {
+ u64 umr_offset = idx & umr_block_mask;
+
+ if (in_block && umr_offset == 0) {
+ mlx5r_umr_update_xlt(mr, blk_start_idx,
+ idx - blk_start_idx, 0,
+ MLX5_IB_UPD_XLT_ZAP |
+ MLX5_IB_UPD_XLT_ATOMIC);
+ in_block = 0;
+ }
+ }
+ }
+ if (in_block)
+ mlx5r_umr_update_xlt(mr, blk_start_idx,
+ idx - blk_start_idx + 1, 0,
+ MLX5_IB_UPD_XLT_ZAP |
+ MLX5_IB_UPD_XLT_ATOMIC);
+
+ mlx5_update_odp_stats(mr, invalidations, invalidations);
+
+ /*
+ * We are now sure that the device will not access the
+ * memory. We can safely unmap it, and mark it as dirty if
+ * needed.
+ */
+
+ ib_umem_odp_unmap_dma_pages(umem_odp, start, end);
+
+ if (unlikely(!umem_odp->npages && mr->parent))
+ destroy_unused_implicit_child_mr(mr);
+out:
+ mutex_unlock(&umem_odp->umem_mutex);
+ return true;
+}
+
+const struct mmu_interval_notifier_ops mlx5_mn_ops = {
+ .invalidate = mlx5_ib_invalidate_range,
+};
+
+static void internal_fill_odp_caps(struct mlx5_ib_dev *dev)
+{
+ struct ib_odp_caps *caps = &dev->odp_caps;
+
+ memset(caps, 0, sizeof(*caps));
+
+ if (!MLX5_CAP_GEN(dev->mdev, pg) || !mlx5r_umr_can_load_pas(dev, 0))
+ return;
+
+ caps->general_caps = IB_ODP_SUPPORT;
+
+ if (MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset))
+ dev->odp_max_size = U64_MAX;
+ else
+ dev->odp_max_size = BIT_ULL(MLX5_MAX_UMR_SHIFT + PAGE_SHIFT);
+
+ if (MLX5_CAP_ODP(dev->mdev, ud_odp_caps.send))
+ caps->per_transport_caps.ud_odp_caps |= IB_ODP_SUPPORT_SEND;
+
+ if (MLX5_CAP_ODP(dev->mdev, ud_odp_caps.srq_receive))
+ caps->per_transport_caps.ud_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
+
+ if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.send))
+ caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_SEND;
+
+ if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.receive))
+ caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_RECV;
+
+ if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.write))
+ caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_WRITE;
+
+ if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.read))
+ caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_READ;
+
+ if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.atomic))
+ caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_ATOMIC;
+
+ if (MLX5_CAP_ODP(dev->mdev, rc_odp_caps.srq_receive))
+ caps->per_transport_caps.rc_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
+
+ if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.send))
+ caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_SEND;
+
+ if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.receive))
+ caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_RECV;
+
+ if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.write))
+ caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_WRITE;
+
+ if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.read))
+ caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_READ;
+
+ if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.atomic))
+ caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_ATOMIC;
+
+ if (MLX5_CAP_ODP(dev->mdev, xrc_odp_caps.srq_receive))
+ caps->per_transport_caps.xrc_odp_caps |= IB_ODP_SUPPORT_SRQ_RECV;
+
+ if (MLX5_CAP_GEN(dev->mdev, fixed_buffer_size) &&
+ MLX5_CAP_GEN(dev->mdev, null_mkey) &&
+ MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset) &&
+ !MLX5_CAP_GEN(dev->mdev, umr_indirect_mkey_disabled))
+ caps->general_caps |= IB_ODP_SUPPORT_IMPLICIT;
+}
+
+static void mlx5_ib_page_fault_resume(struct mlx5_ib_dev *dev,
+ struct mlx5_pagefault *pfault,
+ int error)
+{
+ int wq_num = pfault->event_subtype == MLX5_PFAULT_SUBTYPE_WQE ?
+ pfault->wqe.wq_num : pfault->token;
+ u32 in[MLX5_ST_SZ_DW(page_fault_resume_in)] = {};
+ int err;
+
+ MLX5_SET(page_fault_resume_in, in, opcode, MLX5_CMD_OP_PAGE_FAULT_RESUME);
+ MLX5_SET(page_fault_resume_in, in, page_fault_type, pfault->type);
+ MLX5_SET(page_fault_resume_in, in, token, pfault->token);
+ MLX5_SET(page_fault_resume_in, in, wq_number, wq_num);
+ MLX5_SET(page_fault_resume_in, in, error, !!error);
+
+ err = mlx5_cmd_exec_in(dev->mdev, page_fault_resume, in);
+ if (err)
+ mlx5_ib_err(dev, "Failed to resolve the page fault on WQ 0x%x err %d\n",
+ wq_num, err);
+}
+
+static struct mlx5_ib_mr *implicit_get_child_mr(struct mlx5_ib_mr *imr,
+ unsigned long idx)
+{
+ struct mlx5_ib_dev *dev = mr_to_mdev(imr);
+ struct ib_umem_odp *odp;
+ struct mlx5_ib_mr *mr;
+ struct mlx5_ib_mr *ret;
+ int err;
+
+ odp = ib_umem_odp_alloc_child(to_ib_umem_odp(imr->umem),
+ idx * MLX5_IMR_MTT_SIZE,
+ MLX5_IMR_MTT_SIZE, &mlx5_mn_ops);
+ if (IS_ERR(odp))
+ return ERR_CAST(odp);
+
+ mr = mlx5_mr_cache_alloc(dev, &dev->cache.ent[MLX5_IMR_MTT_CACHE_ENTRY],
+ imr->access_flags);
+ if (IS_ERR(mr)) {
+ ib_umem_odp_release(odp);
+ return mr;
+ }
+
+ mr->access_flags = imr->access_flags;
+ mr->ibmr.pd = imr->ibmr.pd;
+ mr->ibmr.device = &mr_to_mdev(imr)->ib_dev;
+ mr->umem = &odp->umem;
+ mr->ibmr.lkey = mr->mmkey.key;
+ mr->ibmr.rkey = mr->mmkey.key;
+ mr->ibmr.iova = idx * MLX5_IMR_MTT_SIZE;
+ mr->parent = imr;
+ odp->private = mr;
+
+ /*
+ * First refcount is owned by the xarray and second refconut
+ * is returned to the caller.
+ */
+ refcount_set(&mr->mmkey.usecount, 2);
+
+ err = mlx5r_umr_update_xlt(mr, 0,
+ MLX5_IMR_MTT_ENTRIES,
+ PAGE_SHIFT,
+ MLX5_IB_UPD_XLT_ZAP |
+ MLX5_IB_UPD_XLT_ENABLE);
+ if (err) {
+ ret = ERR_PTR(err);
+ goto out_mr;
+ }
+
+ xa_lock(&imr->implicit_children);
+ ret = __xa_cmpxchg(&imr->implicit_children, idx, NULL, mr,
+ GFP_KERNEL);
+ if (unlikely(ret)) {
+ if (xa_is_err(ret)) {
+ ret = ERR_PTR(xa_err(ret));
+ goto out_lock;
+ }
+ /*
+ * Another thread beat us to creating the child mr, use
+ * theirs.
+ */
+ refcount_inc(&ret->mmkey.usecount);
+ goto out_lock;
+ }
+ xa_unlock(&imr->implicit_children);
+
+ mlx5_ib_dbg(mr_to_mdev(imr), "key %x mr %p\n", mr->mmkey.key, mr);
+ return mr;
+
+out_lock:
+ xa_unlock(&imr->implicit_children);
+out_mr:
+ mlx5_ib_dereg_mr(&mr->ibmr, NULL);
+ return ret;
+}
+
+struct mlx5_ib_mr *mlx5_ib_alloc_implicit_mr(struct mlx5_ib_pd *pd,
+ int access_flags)
+{
+ struct mlx5_ib_dev *dev = to_mdev(pd->ibpd.device);
+ struct ib_umem_odp *umem_odp;
+ struct mlx5_ib_mr *imr;
+ int err;
+
+ if (!mlx5r_umr_can_load_pas(dev, MLX5_IMR_MTT_ENTRIES * PAGE_SIZE))
+ return ERR_PTR(-EOPNOTSUPP);
+
+ umem_odp = ib_umem_odp_alloc_implicit(&dev->ib_dev, access_flags);
+ if (IS_ERR(umem_odp))
+ return ERR_CAST(umem_odp);
+
+ imr = mlx5_mr_cache_alloc(dev,
+ &dev->cache.ent[MLX5_IMR_KSM_CACHE_ENTRY],
+ access_flags);
+ if (IS_ERR(imr)) {
+ ib_umem_odp_release(umem_odp);
+ return imr;
+ }
+
+ imr->access_flags = access_flags;
+ imr->ibmr.pd = &pd->ibpd;
+ imr->ibmr.iova = 0;
+ imr->umem = &umem_odp->umem;
+ imr->ibmr.lkey = imr->mmkey.key;
+ imr->ibmr.rkey = imr->mmkey.key;
+ imr->ibmr.device = &dev->ib_dev;
+ imr->is_odp_implicit = true;
+ xa_init(&imr->implicit_children);
+
+ err = mlx5r_umr_update_xlt(imr, 0,
+ mlx5_imr_ksm_entries,
+ MLX5_KSM_PAGE_SHIFT,
+ MLX5_IB_UPD_XLT_INDIRECT |
+ MLX5_IB_UPD_XLT_ZAP |
+ MLX5_IB_UPD_XLT_ENABLE);
+ if (err)
+ goto out_mr;
+
+ err = mlx5r_store_odp_mkey(dev, &imr->mmkey);
+ if (err)
+ goto out_mr;
+
+ mlx5_ib_dbg(dev, "key %x mr %p\n", imr->mmkey.key, imr);
+ return imr;
+out_mr:
+ mlx5_ib_err(dev, "Failed to register MKEY %d\n", err);
+ mlx5_ib_dereg_mr(&imr->ibmr, NULL);
+ return ERR_PTR(err);
+}
+
+void mlx5_ib_free_odp_mr(struct mlx5_ib_mr *mr)
+{
+ struct mlx5_ib_mr *mtt;
+ unsigned long idx;
+
+ /*
+ * If this is an implicit MR it is already invalidated so we can just
+ * delete the children mkeys.
+ */
+ xa_for_each(&mr->implicit_children, idx, mtt) {
+ xa_erase(&mr->implicit_children, idx);
+ mlx5_ib_dereg_mr(&mtt->ibmr, NULL);
+ }
+}
+
+#define MLX5_PF_FLAGS_DOWNGRADE BIT(1)
+#define MLX5_PF_FLAGS_SNAPSHOT BIT(2)
+#define MLX5_PF_FLAGS_ENABLE BIT(3)
+static int pagefault_real_mr(struct mlx5_ib_mr *mr, struct ib_umem_odp *odp,
+ u64 user_va, size_t bcnt, u32 *bytes_mapped,
+ u32 flags)
+{
+ int page_shift, ret, np;
+ bool downgrade = flags & MLX5_PF_FLAGS_DOWNGRADE;
+ u64 access_mask;
+ u64 start_idx;
+ bool fault = !(flags & MLX5_PF_FLAGS_SNAPSHOT);
+ u32 xlt_flags = MLX5_IB_UPD_XLT_ATOMIC;
+
+ if (flags & MLX5_PF_FLAGS_ENABLE)
+ xlt_flags |= MLX5_IB_UPD_XLT_ENABLE;
+
+ page_shift = odp->page_shift;
+ start_idx = (user_va - ib_umem_start(odp)) >> page_shift;
+ access_mask = ODP_READ_ALLOWED_BIT;
+
+ if (odp->umem.writable && !downgrade)
+ access_mask |= ODP_WRITE_ALLOWED_BIT;
+
+ np = ib_umem_odp_map_dma_and_lock(odp, user_va, bcnt, access_mask, fault);
+ if (np < 0)
+ return np;
+
+ /*
+ * No need to check whether the MTTs really belong to this MR, since
+ * ib_umem_odp_map_dma_and_lock already checks this.
+ */
+ ret = mlx5r_umr_update_xlt(mr, start_idx, np, page_shift, xlt_flags);
+ mutex_unlock(&odp->umem_mutex);
+
+ if (ret < 0) {
+ if (ret != -EAGAIN)
+ mlx5_ib_err(mr_to_mdev(mr),
+ "Failed to update mkey page tables\n");
+ goto out;
+ }
+
+ if (bytes_mapped) {
+ u32 new_mappings = (np << page_shift) -
+ (user_va - round_down(user_va, 1 << page_shift));
+
+ *bytes_mapped += min_t(u32, new_mappings, bcnt);
+ }
+
+ return np << (page_shift - PAGE_SHIFT);
+
+out:
+ return ret;
+}
+
+static int 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)
+{
+ unsigned long end_idx = (user_va + bcnt - 1) >> MLX5_IMR_MTT_SHIFT;
+ unsigned long upd_start_idx = end_idx + 1;
+ unsigned long upd_len = 0;
+ unsigned long npages = 0;
+ int err;
+ int ret;
+
+ if (unlikely(user_va >= mlx5_imr_ksm_entries * MLX5_IMR_MTT_SIZE ||
+ mlx5_imr_ksm_entries * MLX5_IMR_MTT_SIZE - user_va < bcnt))
+ return -EFAULT;
+
+ /* Fault each child mr that intersects with our interval. */
+ while (bcnt) {
+ unsigned long idx = user_va >> MLX5_IMR_MTT_SHIFT;
+ struct ib_umem_odp *umem_odp;
+ struct mlx5_ib_mr *mtt;
+ u64 len;
+
+ xa_lock(&imr->implicit_children);
+ mtt = xa_load(&imr->implicit_children, idx);
+ if (unlikely(!mtt)) {
+ xa_unlock(&imr->implicit_children);
+ mtt = implicit_get_child_mr(imr, idx);
+ if (IS_ERR(mtt)) {
+ ret = PTR_ERR(mtt);
+ goto out;
+ }
+ upd_start_idx = min(upd_start_idx, idx);
+ upd_len = idx - upd_start_idx + 1;
+ } else {
+ refcount_inc(&mtt->mmkey.usecount);
+ xa_unlock(&imr->implicit_children);
+ }
+
+ umem_odp = to_ib_umem_odp(mtt->umem);
+ len = min_t(u64, user_va + bcnt, ib_umem_end(umem_odp)) -
+ user_va;
+
+ ret = pagefault_real_mr(mtt, umem_odp, user_va, len,
+ bytes_mapped, flags);
+
+ mlx5r_deref_odp_mkey(&mtt->mmkey);
+
+ if (ret < 0)
+ goto out;
+ user_va += len;
+ bcnt -= len;
+ npages += ret;
+ }
+
+ ret = npages;
+
+ /*
+ * Any time the implicit_children are changed we must perform an
+ * update of the xlt before exiting to ensure the HW and the
+ * implicit_children remains synchronized.
+ */
+out:
+ if (likely(!upd_len))
+ return ret;
+
+ /*
+ * Notice this is not strictly ordered right, the KSM is updated after
+ * the implicit_children is updated, so a parallel page fault could
+ * see a MR that is not yet visible in the KSM. This is similar to a
+ * parallel page fault seeing a MR that is being concurrently removed
+ * from the KSM. Both of these improbable situations are resolved
+ * safely by resuming the HW and then taking another page fault. The
+ * next pagefault handler will see the new information.
+ */
+ mutex_lock(&odp_imr->umem_mutex);
+ err = mlx5r_umr_update_xlt(imr, upd_start_idx, upd_len, 0,
+ MLX5_IB_UPD_XLT_INDIRECT |
+ MLX5_IB_UPD_XLT_ATOMIC);
+ mutex_unlock(&odp_imr->umem_mutex);
+ if (err) {
+ mlx5_ib_err(mr_to_mdev(imr), "Failed to update PAS\n");
+ return err;
+ }
+ return ret;
+}
+
+static int pagefault_dmabuf_mr(struct mlx5_ib_mr *mr, size_t bcnt,
+ u32 *bytes_mapped, u32 flags)
+{
+ struct ib_umem_dmabuf *umem_dmabuf = to_ib_umem_dmabuf(mr->umem);
+ u32 xlt_flags = 0;
+ int err;
+ unsigned int page_size;
+
+ if (flags & MLX5_PF_FLAGS_ENABLE)
+ xlt_flags |= MLX5_IB_UPD_XLT_ENABLE;
+
+ dma_resv_lock(umem_dmabuf->attach->dmabuf->resv, NULL);
+ err = ib_umem_dmabuf_map_pages(umem_dmabuf);
+ if (err) {
+ dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv);
+ return err;
+ }
+
+ page_size = mlx5_umem_find_best_pgsz(&umem_dmabuf->umem, mkc,
+ log_page_size, 0,
+ umem_dmabuf->umem.iova);
+ if (unlikely(page_size < PAGE_SIZE)) {
+ ib_umem_dmabuf_unmap_pages(umem_dmabuf);
+ err = -EINVAL;
+ } else {
+ err = mlx5r_umr_update_mr_pas(mr, xlt_flags);
+ }
+ dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv);
+
+ if (err)
+ return err;
+
+ if (bytes_mapped)
+ *bytes_mapped += bcnt;
+
+ return ib_umem_num_pages(mr->umem);
+}
+
+/*
+ * Returns:
+ * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are
+ * not accessible, or the MR is no longer valid.
+ * -EAGAIN/-ENOMEM: The operation should be retried
+ *
+ * -EINVAL/others: General internal malfunction
+ * >0: Number of pages mapped
+ */
+static int pagefault_mr(struct mlx5_ib_mr *mr, u64 io_virt, size_t bcnt,
+ u32 *bytes_mapped, u32 flags)
+{
+ struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
+
+ if (unlikely(io_virt < mr->ibmr.iova))
+ return -EFAULT;
+
+ if (mr->umem->is_dmabuf)
+ return pagefault_dmabuf_mr(mr, bcnt, bytes_mapped, flags);
+
+ if (!odp->is_implicit_odp) {
+ u64 user_va;
+
+ if (check_add_overflow(io_virt - mr->ibmr.iova,
+ (u64)odp->umem.address, &user_va))
+ return -EFAULT;
+ if (unlikely(user_va >= ib_umem_end(odp) ||
+ ib_umem_end(odp) - user_va < bcnt))
+ return -EFAULT;
+ return pagefault_real_mr(mr, odp, user_va, bcnt, bytes_mapped,
+ flags);
+ }
+ return pagefault_implicit_mr(mr, odp, io_virt, bcnt, bytes_mapped,
+ flags);
+}
+
+int mlx5_ib_init_odp_mr(struct mlx5_ib_mr *mr)
+{
+ int ret;
+
+ ret = pagefault_real_mr(mr, to_ib_umem_odp(mr->umem), mr->umem->address,
+ mr->umem->length, NULL,
+ MLX5_PF_FLAGS_SNAPSHOT | MLX5_PF_FLAGS_ENABLE);
+ return ret >= 0 ? 0 : ret;
+}
+
+int mlx5_ib_init_dmabuf_mr(struct mlx5_ib_mr *mr)
+{
+ int ret;
+
+ ret = pagefault_dmabuf_mr(mr, mr->umem->length, NULL,
+ MLX5_PF_FLAGS_ENABLE);
+
+ return ret >= 0 ? 0 : ret;
+}
+
+struct pf_frame {
+ struct pf_frame *next;
+ u32 key;
+ u64 io_virt;
+ size_t bcnt;
+ int depth;
+};
+
+static bool mkey_is_eq(struct mlx5_ib_mkey *mmkey, u32 key)
+{
+ if (!mmkey)
+ return false;
+ if (mmkey->type == MLX5_MKEY_MW ||
+ mmkey->type == MLX5_MKEY_INDIRECT_DEVX)
+ return mlx5_base_mkey(mmkey->key) == mlx5_base_mkey(key);
+ return mmkey->key == key;
+}
+
+/*
+ * Handle a single data segment in a page-fault WQE or RDMA region.
+ *
+ * Returns number of OS pages retrieved on success. The caller may continue to
+ * the next data segment.
+ * Can return the following error codes:
+ * -EAGAIN to designate a temporary error. The caller will abort handling the
+ * page fault and resolve it.
+ * -EFAULT when there's an error mapping the requested pages. The caller will
+ * abort the page fault handling.
+ */
+static int 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)
+{
+ int npages = 0, ret, i, outlen, cur_outlen = 0, depth = 0;
+ struct pf_frame *head = NULL, *frame;
+ struct mlx5_ib_mkey *mmkey;
+ struct mlx5_ib_mr *mr;
+ struct mlx5_klm *pklm;
+ u32 *out = NULL;
+ size_t offset;
+
+ io_virt += *bytes_committed;
+ bcnt -= *bytes_committed;
+
+next_mr:
+ xa_lock(&dev->odp_mkeys);
+ mmkey = xa_load(&dev->odp_mkeys, mlx5_base_mkey(key));
+ if (!mmkey) {
+ xa_unlock(&dev->odp_mkeys);
+ mlx5_ib_dbg(
+ dev,
+ "skipping non ODP MR (lkey=0x%06x) in page fault handler.\n",
+ key);
+ if (bytes_mapped)
+ *bytes_mapped += bcnt;
+ /*
+ * The user could specify a SGL with multiple lkeys and only
+ * some of them are ODP. Treat the non-ODP ones as fully
+ * faulted.
+ */
+ ret = 0;
+ goto end;
+ }
+ refcount_inc(&mmkey->usecount);
+ xa_unlock(&dev->odp_mkeys);
+
+ if (!mkey_is_eq(mmkey, key)) {
+ mlx5_ib_dbg(dev, "failed to find mkey %x\n", key);
+ ret = -EFAULT;
+ goto end;
+ }
+
+ switch (mmkey->type) {
+ case MLX5_MKEY_MR:
+ mr = container_of(mmkey, struct mlx5_ib_mr, mmkey);
+
+ ret = pagefault_mr(mr, io_virt, bcnt, bytes_mapped, 0);
+ if (ret < 0)
+ goto end;
+
+ mlx5_update_odp_stats(mr, faults, ret);
+
+ npages += ret;
+ ret = 0;
+ break;
+
+ case MLX5_MKEY_MW:
+ case MLX5_MKEY_INDIRECT_DEVX:
+ if (depth >= MLX5_CAP_GEN(dev->mdev, max_indirection)) {
+ mlx5_ib_dbg(dev, "indirection level exceeded\n");
+ ret = -EFAULT;
+ goto end;
+ }
+
+ outlen = MLX5_ST_SZ_BYTES(query_mkey_out) +
+ sizeof(*pklm) * (mmkey->ndescs - 2);
+
+ if (outlen > cur_outlen) {
+ kfree(out);
+ out = kzalloc(outlen, GFP_KERNEL);
+ if (!out) {
+ ret = -ENOMEM;
+ goto end;
+ }
+ cur_outlen = outlen;
+ }
+
+ pklm = (struct mlx5_klm *)MLX5_ADDR_OF(query_mkey_out, out,
+ bsf0_klm0_pas_mtt0_1);
+
+ ret = mlx5_core_query_mkey(dev->mdev, mmkey->key, out, outlen);
+ if (ret)
+ goto end;
+
+ offset = io_virt - MLX5_GET64(query_mkey_out, out,
+ memory_key_mkey_entry.start_addr);
+
+ for (i = 0; bcnt && i < mmkey->ndescs; i++, pklm++) {
+ if (offset >= be32_to_cpu(pklm->bcount)) {
+ offset -= be32_to_cpu(pklm->bcount);
+ continue;
+ }
+
+ frame = kzalloc(sizeof(*frame), GFP_KERNEL);
+ if (!frame) {
+ ret = -ENOMEM;
+ goto end;
+ }
+
+ frame->key = be32_to_cpu(pklm->key);
+ frame->io_virt = be64_to_cpu(pklm->va) + offset;
+ frame->bcnt = min_t(size_t, bcnt,
+ be32_to_cpu(pklm->bcount) - offset);
+ frame->depth = depth + 1;
+ frame->next = head;
+ head = frame;
+
+ bcnt -= frame->bcnt;
+ offset = 0;
+ }
+ break;
+
+ default:
+ mlx5_ib_dbg(dev, "wrong mkey type %d\n", mmkey->type);
+ ret = -EFAULT;
+ goto end;
+ }
+
+ if (head) {
+ frame = head;
+ head = frame->next;
+
+ key = frame->key;
+ io_virt = frame->io_virt;
+ bcnt = frame->bcnt;
+ depth = frame->depth;
+ kfree(frame);
+
+ mlx5r_deref_odp_mkey(mmkey);
+ goto next_mr;
+ }
+
+end:
+ if (mmkey)
+ mlx5r_deref_odp_mkey(mmkey);
+ while (head) {
+ frame = head;
+ head = frame->next;
+ kfree(frame);
+ }
+ kfree(out);
+
+ *bytes_committed = 0;
+ return ret ? ret : npages;
+}
+
+/*
+ * Parse a series of data segments for page fault handling.
+ *
+ * @dev: Pointer to mlx5 IB device
+ * @pfault: contains page fault information.
+ * @wqe: points at the first data segment in the WQE.
+ * @wqe_end: points after the end of the WQE.
+ * @bytes_mapped: receives the number of bytes that the function was able to
+ * map. This allows the caller to decide intelligently whether
+ * enough memory was mapped to resolve the page fault
+ * successfully (e.g. enough for the next MTU, or the entire
+ * WQE).
+ * @total_wqe_bytes: receives the total data size of this WQE in bytes (minus
+ * the committed bytes).
+ * @receive_queue: receive WQE end of sg list
+ *
+ * Returns the number of pages loaded if positive, zero for an empty WQE, or a
+ * negative error code.
+ */
+static int 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)
+{
+ int ret = 0, npages = 0;
+ u64 io_virt;
+ u32 key;
+ u32 byte_count;
+ size_t bcnt;
+ int inline_segment;
+
+ if (bytes_mapped)
+ *bytes_mapped = 0;
+ if (total_wqe_bytes)
+ *total_wqe_bytes = 0;
+
+ while (wqe < wqe_end) {
+ struct mlx5_wqe_data_seg *dseg = wqe;
+
+ io_virt = be64_to_cpu(dseg->addr);
+ key = be32_to_cpu(dseg->lkey);
+ byte_count = be32_to_cpu(dseg->byte_count);
+ inline_segment = !!(byte_count & MLX5_INLINE_SEG);
+ bcnt = byte_count & ~MLX5_INLINE_SEG;
+
+ if (inline_segment) {
+ bcnt = bcnt & MLX5_WQE_INLINE_SEG_BYTE_COUNT_MASK;
+ wqe += ALIGN(sizeof(struct mlx5_wqe_inline_seg) + bcnt,
+ 16);
+ } else {
+ wqe += sizeof(*dseg);
+ }
+
+ /* receive WQE end of sg list. */
+ if (receive_queue && bcnt == 0 && key == MLX5_INVALID_LKEY &&
+ io_virt == 0)
+ break;
+
+ if (!inline_segment && total_wqe_bytes) {
+ *total_wqe_bytes += bcnt - min_t(size_t, bcnt,
+ pfault->bytes_committed);
+ }
+
+ /* A zero length data segment designates a length of 2GB. */
+ if (bcnt == 0)
+ bcnt = 1U << 31;
+
+ if (inline_segment || bcnt <= pfault->bytes_committed) {
+ pfault->bytes_committed -=
+ min_t(size_t, bcnt,
+ pfault->bytes_committed);
+ continue;
+ }
+
+ ret = pagefault_single_data_segment(dev, NULL, key,
+ io_virt, bcnt,
+ &pfault->bytes_committed,
+ bytes_mapped);
+ if (ret < 0)
+ break;
+ npages += ret;
+ }
+
+ return ret < 0 ? ret : npages;
+}
+
+/*
+ * Parse initiator WQE. Advances the wqe pointer to point at the
+ * scatter-gather list, and set wqe_end to the end of the WQE.
+ */
+static int 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)
+{
+ struct mlx5_wqe_ctrl_seg *ctrl = *wqe;
+ u16 wqe_index = pfault->wqe.wqe_index;
+ struct mlx5_base_av *av;
+ unsigned ds, opcode;
+ u32 qpn = qp->trans_qp.base.mqp.qpn;
+
+ ds = be32_to_cpu(ctrl->qpn_ds) & MLX5_WQE_CTRL_DS_MASK;
+ if (ds * MLX5_WQE_DS_UNITS > wqe_length) {
+ mlx5_ib_err(dev, "Unable to read the complete WQE. ds = 0x%x, ret = 0x%x\n",
+ ds, wqe_length);
+ return -EFAULT;
+ }
+
+ if (ds == 0) {
+ mlx5_ib_err(dev, "Got WQE with zero DS. wqe_index=%x, qpn=%x\n",
+ wqe_index, qpn);
+ return -EFAULT;
+ }
+
+ *wqe_end = *wqe + ds * MLX5_WQE_DS_UNITS;
+ *wqe += sizeof(*ctrl);
+
+ opcode = be32_to_cpu(ctrl->opmod_idx_opcode) &
+ MLX5_WQE_CTRL_OPCODE_MASK;
+
+ if (qp->type == IB_QPT_XRC_INI)
+ *wqe += sizeof(struct mlx5_wqe_xrc_seg);
+
+ if (qp->type == IB_QPT_UD || qp->type == MLX5_IB_QPT_DCI) {
+ av = *wqe;
+ if (av->dqp_dct & cpu_to_be32(MLX5_EXTENDED_UD_AV))
+ *wqe += sizeof(struct mlx5_av);
+ else
+ *wqe += sizeof(struct mlx5_base_av);
+ }
+
+ switch (opcode) {
+ case MLX5_OPCODE_RDMA_WRITE:
+ case MLX5_OPCODE_RDMA_WRITE_IMM:
+ case MLX5_OPCODE_RDMA_READ:
+ *wqe += sizeof(struct mlx5_wqe_raddr_seg);
+ break;
+ case MLX5_OPCODE_ATOMIC_CS:
+ case MLX5_OPCODE_ATOMIC_FA:
+ *wqe += sizeof(struct mlx5_wqe_raddr_seg);
+ *wqe += sizeof(struct mlx5_wqe_atomic_seg);
+ break;
+ }
+
+ return 0;
+}
+
+/*
+ * Parse responder WQE and set wqe_end to the end of the WQE.
+ */
+static int 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)
+{
+ int wqe_size = 1 << srq->msrq.wqe_shift;
+
+ if (wqe_size > wqe_length) {
+ mlx5_ib_err(dev, "Couldn't read all of the receive WQE's content\n");
+ return -EFAULT;
+ }
+
+ *wqe_end = *wqe + wqe_size;
+ *wqe += sizeof(struct mlx5_wqe_srq_next_seg);
+
+ return 0;
+}
+
+static int 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)
+{
+ struct mlx5_ib_wq *wq = &qp->rq;
+ int wqe_size = 1 << wq->wqe_shift;
+
+ if (qp->flags_en & MLX5_QP_FLAG_SIGNATURE) {
+ mlx5_ib_err(dev, "ODP fault with WQE signatures is not supported\n");
+ return -EFAULT;
+ }
+
+ if (wqe_size > wqe_length) {
+ mlx5_ib_err(dev, "Couldn't read all of the receive WQE's content\n");
+ return -EFAULT;
+ }
+
+ *wqe_end = wqe + wqe_size;
+
+ return 0;
+}
+
+static inline struct mlx5_core_rsc_common *odp_get_rsc(struct mlx5_ib_dev *dev,
+ u32 wq_num, int pf_type)
+{
+ struct mlx5_core_rsc_common *common = NULL;
+ struct mlx5_core_srq *srq;
+
+ switch (pf_type) {
+ case MLX5_WQE_PF_TYPE_RMP:
+ srq = mlx5_cmd_get_srq(dev, wq_num);
+ if (srq)
+ common = &srq->common;
+ break;
+ case MLX5_WQE_PF_TYPE_REQ_SEND_OR_WRITE:
+ case MLX5_WQE_PF_TYPE_RESP:
+ case MLX5_WQE_PF_TYPE_REQ_READ_OR_ATOMIC:
+ common = mlx5_core_res_hold(dev, wq_num, MLX5_RES_QP);
+ break;
+ default:
+ break;
+ }
+
+ return common;
+}
+
+static inline struct mlx5_ib_qp *res_to_qp(struct mlx5_core_rsc_common *res)
+{
+ struct mlx5_core_qp *mqp = (struct mlx5_core_qp *)res;
+
+ return to_mibqp(mqp);
+}
+
+static inline struct mlx5_ib_srq *res_to_srq(struct mlx5_core_rsc_common *res)
+{
+ struct mlx5_core_srq *msrq =
+ container_of(res, struct mlx5_core_srq, common);
+
+ return to_mibsrq(msrq);
+}
+
+static void mlx5_ib_mr_wqe_pfault_handler(struct mlx5_ib_dev *dev,
+ struct mlx5_pagefault *pfault)
+{
+ bool sq = pfault->type & MLX5_PFAULT_REQUESTOR;
+ u16 wqe_index = pfault->wqe.wqe_index;
+ void *wqe, *wqe_start = NULL, *wqe_end = NULL;
+ u32 bytes_mapped, total_wqe_bytes;
+ struct mlx5_core_rsc_common *res;
+ int resume_with_error = 1;
+ struct mlx5_ib_qp *qp;
+ size_t bytes_copied;
+ int ret = 0;
+
+ res = odp_get_rsc(dev, pfault->wqe.wq_num, pfault->type);
+ if (!res) {
+ mlx5_ib_dbg(dev, "wqe page fault for missing resource %d\n", pfault->wqe.wq_num);
+ return;
+ }
+
+ if (res->res != MLX5_RES_QP && res->res != MLX5_RES_SRQ &&
+ res->res != MLX5_RES_XSRQ) {
+ mlx5_ib_err(dev, "wqe page fault for unsupported type %d\n",
+ pfault->type);
+ goto resolve_page_fault;
+ }
+
+ wqe_start = (void *)__get_free_page(GFP_KERNEL);
+ if (!wqe_start) {
+ mlx5_ib_err(dev, "Error allocating memory for IO page fault handling.\n");
+ goto resolve_page_fault;
+ }
+
+ wqe = wqe_start;
+ qp = (res->res == MLX5_RES_QP) ? res_to_qp(res) : NULL;
+ if (qp && sq) {
+ ret = mlx5_ib_read_wqe_sq(qp, wqe_index, wqe, PAGE_SIZE,
+ &bytes_copied);
+ if (ret)
+ goto read_user;
+ ret = mlx5_ib_mr_initiator_pfault_handler(
+ dev, pfault, qp, &wqe, &wqe_end, bytes_copied);
+ } else if (qp && !sq) {
+ ret = mlx5_ib_read_wqe_rq(qp, wqe_index, wqe, PAGE_SIZE,
+ &bytes_copied);
+ if (ret)
+ goto read_user;
+ ret = mlx5_ib_mr_responder_pfault_handler_rq(
+ dev, qp, wqe, &wqe_end, bytes_copied);
+ } else if (!qp) {
+ struct mlx5_ib_srq *srq = res_to_srq(res);
+
+ ret = mlx5_ib_read_wqe_srq(srq, wqe_index, wqe, PAGE_SIZE,
+ &bytes_copied);
+ if (ret)
+ goto read_user;
+ ret = mlx5_ib_mr_responder_pfault_handler_srq(
+ dev, srq, &wqe, &wqe_end, bytes_copied);
+ }
+
+ if (ret < 0 || wqe >= wqe_end)
+ goto resolve_page_fault;
+
+ ret = pagefault_data_segments(dev, pfault, wqe, wqe_end, &bytes_mapped,
+ &total_wqe_bytes, !sq);
+ if (ret == -EAGAIN)
+ goto out;
+
+ if (ret < 0 || total_wqe_bytes > bytes_mapped)
+ goto resolve_page_fault;
+
+out:
+ ret = 0;
+ resume_with_error = 0;
+
+read_user:
+ if (ret)
+ mlx5_ib_err(
+ dev,
+ "Failed reading a WQE following page fault, error %d, wqe_index %x, qpn %x\n",
+ ret, wqe_index, pfault->token);
+
+resolve_page_fault:
+ mlx5_ib_page_fault_resume(dev, pfault, resume_with_error);
+ mlx5_ib_dbg(dev, "PAGE FAULT completed. QP 0x%x resume_with_error=%d, type: 0x%x\n",
+ pfault->wqe.wq_num, resume_with_error,
+ pfault->type);
+ mlx5_core_res_put(res);
+ free_page((unsigned long)wqe_start);
+}
+
+static int pages_in_range(u64 address, u32 length)
+{
+ return (ALIGN(address + length, PAGE_SIZE) -
+ (address & PAGE_MASK)) >> PAGE_SHIFT;
+}
+
+static void mlx5_ib_mr_rdma_pfault_handler(struct mlx5_ib_dev *dev,
+ struct mlx5_pagefault *pfault)
+{
+ u64 address;
+ u32 length;
+ u32 prefetch_len = pfault->bytes_committed;
+ int prefetch_activated = 0;
+ u32 rkey = pfault->rdma.r_key;
+ int ret;
+
+ /* The RDMA responder handler handles the page fault in two parts.
+ * First it brings the necessary pages for the current packet
+ * (and uses the pfault context), and then (after resuming the QP)
+ * prefetches more pages. The second operation cannot use the pfault
+ * context and therefore uses the dummy_pfault context allocated on
+ * the stack */
+ pfault->rdma.rdma_va += pfault->bytes_committed;
+ pfault->rdma.rdma_op_len -= min(pfault->bytes_committed,
+ pfault->rdma.rdma_op_len);
+ pfault->bytes_committed = 0;
+
+ address = pfault->rdma.rdma_va;
+ length = pfault->rdma.rdma_op_len;
+
+ /* For some operations, the hardware cannot tell the exact message
+ * length, and in those cases it reports zero. Use prefetch
+ * logic. */
+ if (length == 0) {
+ prefetch_activated = 1;
+ length = pfault->rdma.packet_size;
+ prefetch_len = min(MAX_PREFETCH_LEN, prefetch_len);
+ }
+
+ ret = pagefault_single_data_segment(dev, NULL, rkey, address, length,
+ &pfault->bytes_committed, NULL);
+ if (ret == -EAGAIN) {
+ /* We're racing with an invalidation, don't prefetch */
+ prefetch_activated = 0;
+ } else if (ret < 0 || pages_in_range(address, length) > ret) {
+ mlx5_ib_page_fault_resume(dev, pfault, 1);
+ if (ret != -ENOENT)
+ mlx5_ib_dbg(dev, "PAGE FAULT error %d. QP 0x%x, type: 0x%x\n",
+ ret, pfault->token, pfault->type);
+ return;
+ }
+
+ mlx5_ib_page_fault_resume(dev, pfault, 0);
+ mlx5_ib_dbg(dev, "PAGE FAULT completed. QP 0x%x, type: 0x%x, prefetch_activated: %d\n",
+ pfault->token, pfault->type,
+ prefetch_activated);
+
+ /* At this point, there might be a new pagefault already arriving in
+ * the eq, switch to the dummy pagefault for the rest of the
+ * processing. We're still OK with the objects being alive as the
+ * work-queue is being fenced. */
+
+ if (prefetch_activated) {
+ u32 bytes_committed = 0;
+
+ ret = pagefault_single_data_segment(dev, NULL, rkey, address,
+ prefetch_len,
+ &bytes_committed, NULL);
+ if (ret < 0 && ret != -EAGAIN) {
+ mlx5_ib_dbg(dev, "Prefetch failed. ret: %d, QP 0x%x, address: 0x%.16llx, length = 0x%.16x\n",
+ ret, pfault->token, address, prefetch_len);
+ }
+ }
+}
+
+static void mlx5_ib_pfault(struct mlx5_ib_dev *dev, struct mlx5_pagefault *pfault)
+{
+ u8 event_subtype = pfault->event_subtype;
+
+ switch (event_subtype) {
+ case MLX5_PFAULT_SUBTYPE_WQE:
+ mlx5_ib_mr_wqe_pfault_handler(dev, pfault);
+ break;
+ case MLX5_PFAULT_SUBTYPE_RDMA:
+ mlx5_ib_mr_rdma_pfault_handler(dev, pfault);
+ break;
+ default:
+ mlx5_ib_err(dev, "Invalid page fault event subtype: 0x%x\n",
+ event_subtype);
+ mlx5_ib_page_fault_resume(dev, pfault, 1);
+ }
+}
+
+static void mlx5_ib_eqe_pf_action(struct work_struct *work)
+{
+ struct mlx5_pagefault *pfault = container_of(work,
+ struct mlx5_pagefault,
+ work);
+ struct mlx5_ib_pf_eq *eq = pfault->eq;
+
+ mlx5_ib_pfault(eq->dev, pfault);
+ mempool_free(pfault, eq->pool);
+}
+
+static void mlx5_ib_eq_pf_process(struct mlx5_ib_pf_eq *eq)
+{
+ struct mlx5_eqe_page_fault *pf_eqe;
+ struct mlx5_pagefault *pfault;
+ struct mlx5_eqe *eqe;
+ int cc = 0;
+
+ while ((eqe = mlx5_eq_get_eqe(eq->core, cc))) {
+ pfault = mempool_alloc(eq->pool, GFP_ATOMIC);
+ if (!pfault) {
+ schedule_work(&eq->work);
+ break;
+ }
+
+ pf_eqe = &eqe->data.page_fault;
+ pfault->event_subtype = eqe->sub_type;
+ pfault->bytes_committed = be32_to_cpu(pf_eqe->bytes_committed);
+
+ mlx5_ib_dbg(eq->dev,
+ "PAGE_FAULT: subtype: 0x%02x, bytes_committed: 0x%06x\n",
+ eqe->sub_type, pfault->bytes_committed);
+
+ switch (eqe->sub_type) {
+ case MLX5_PFAULT_SUBTYPE_RDMA:
+ /* RDMA based event */
+ pfault->type =
+ be32_to_cpu(pf_eqe->rdma.pftype_token) >> 24;
+ pfault->token =
+ be32_to_cpu(pf_eqe->rdma.pftype_token) &
+ MLX5_24BIT_MASK;
+ pfault->rdma.r_key =
+ be32_to_cpu(pf_eqe->rdma.r_key);
+ pfault->rdma.packet_size =
+ be16_to_cpu(pf_eqe->rdma.packet_length);
+ pfault->rdma.rdma_op_len =
+ be32_to_cpu(pf_eqe->rdma.rdma_op_len);
+ pfault->rdma.rdma_va =
+ be64_to_cpu(pf_eqe->rdma.rdma_va);
+ mlx5_ib_dbg(eq->dev,
+ "PAGE_FAULT: type:0x%x, token: 0x%06x, r_key: 0x%08x\n",
+ pfault->type, pfault->token,
+ pfault->rdma.r_key);
+ mlx5_ib_dbg(eq->dev,
+ "PAGE_FAULT: rdma_op_len: 0x%08x, rdma_va: 0x%016llx\n",
+ pfault->rdma.rdma_op_len,
+ pfault->rdma.rdma_va);
+ break;
+
+ case MLX5_PFAULT_SUBTYPE_WQE:
+ /* WQE based event */
+ pfault->type =
+ (be32_to_cpu(pf_eqe->wqe.pftype_wq) >> 24) & 0x7;
+ pfault->token =
+ be32_to_cpu(pf_eqe->wqe.token);
+ pfault->wqe.wq_num =
+ be32_to_cpu(pf_eqe->wqe.pftype_wq) &
+ MLX5_24BIT_MASK;
+ pfault->wqe.wqe_index =
+ be16_to_cpu(pf_eqe->wqe.wqe_index);
+ pfault->wqe.packet_size =
+ be16_to_cpu(pf_eqe->wqe.packet_length);
+ mlx5_ib_dbg(eq->dev,
+ "PAGE_FAULT: type:0x%x, token: 0x%06x, wq_num: 0x%06x, wqe_index: 0x%04x\n",
+ pfault->type, pfault->token,
+ pfault->wqe.wq_num,
+ pfault->wqe.wqe_index);
+ break;
+
+ default:
+ mlx5_ib_warn(eq->dev,
+ "Unsupported page fault event sub-type: 0x%02hhx\n",
+ eqe->sub_type);
+ /* Unsupported page faults should still be
+ * resolved by the page fault handler
+ */
+ }
+
+ pfault->eq = eq;
+ INIT_WORK(&pfault->work, mlx5_ib_eqe_pf_action);
+ queue_work(eq->wq, &pfault->work);
+
+ cc = mlx5_eq_update_cc(eq->core, ++cc);
+ }
+
+ mlx5_eq_update_ci(eq->core, cc, 1);
+}
+
+static int mlx5_ib_eq_pf_int(struct notifier_block *nb, unsigned long type,
+ void *data)
+{
+ struct mlx5_ib_pf_eq *eq =
+ container_of(nb, struct mlx5_ib_pf_eq, irq_nb);
+ unsigned long flags;
+
+ if (spin_trylock_irqsave(&eq->lock, flags)) {
+ mlx5_ib_eq_pf_process(eq);
+ spin_unlock_irqrestore(&eq->lock, flags);
+ } else {
+ schedule_work(&eq->work);
+ }
+
+ return IRQ_HANDLED;
+}
+
+/* mempool_refill() was proposed but unfortunately wasn't accepted
+ * http://lkml.iu.edu/hypermail/linux/kernel/1512.1/05073.html
+ * Cheap workaround.
+ */
+static void mempool_refill(mempool_t *pool)
+{
+ while (pool->curr_nr < pool->min_nr)
+ mempool_free(mempool_alloc(pool, GFP_KERNEL), pool);
+}
+
+static void mlx5_ib_eq_pf_action(struct work_struct *work)
+{
+ struct mlx5_ib_pf_eq *eq =
+ container_of(work, struct mlx5_ib_pf_eq, work);
+
+ mempool_refill(eq->pool);
+
+ spin_lock_irq(&eq->lock);
+ mlx5_ib_eq_pf_process(eq);
+ spin_unlock_irq(&eq->lock);
+}
+
+enum {
+ MLX5_IB_NUM_PF_EQE = 0x1000,
+ MLX5_IB_NUM_PF_DRAIN = 64,
+};
+
+int mlx5r_odp_create_eq(struct mlx5_ib_dev *dev, struct mlx5_ib_pf_eq *eq)
+{
+ struct mlx5_eq_param param = {};
+ int err = 0;
+
+ mutex_lock(&dev->odp_eq_mutex);
+ if (eq->core)
+ goto unlock;
+ INIT_WORK(&eq->work, mlx5_ib_eq_pf_action);
+ spin_lock_init(&eq->lock);
+ eq->dev = dev;
+
+ eq->pool = mempool_create_kmalloc_pool(MLX5_IB_NUM_PF_DRAIN,
+ sizeof(struct mlx5_pagefault));
+ if (!eq->pool) {
+ err = -ENOMEM;
+ goto unlock;
+ }
+
+ eq->wq = alloc_workqueue("mlx5_ib_page_fault",
+ WQ_HIGHPRI | WQ_UNBOUND | WQ_MEM_RECLAIM,
+ MLX5_NUM_CMD_EQE);
+ if (!eq->wq) {
+ err = -ENOMEM;
+ goto err_mempool;
+ }
+
+ eq->irq_nb.notifier_call = mlx5_ib_eq_pf_int;
+ param = (struct mlx5_eq_param) {
+ .nent = MLX5_IB_NUM_PF_EQE,
+ };
+ param.mask[0] = 1ull << MLX5_EVENT_TYPE_PAGE_FAULT;
+ eq->core = mlx5_eq_create_generic(dev->mdev, &param);
+ if (IS_ERR(eq->core)) {
+ err = PTR_ERR(eq->core);
+ goto err_wq;
+ }
+ err = mlx5_eq_enable(dev->mdev, eq->core, &eq->irq_nb);
+ if (err) {
+ mlx5_ib_err(dev, "failed to enable odp EQ %d\n", err);
+ goto err_eq;
+ }
+
+ mutex_unlock(&dev->odp_eq_mutex);
+ return 0;
+err_eq:
+ mlx5_eq_destroy_generic(dev->mdev, eq->core);
+err_wq:
+ eq->core = NULL;
+ destroy_workqueue(eq->wq);
+err_mempool:
+ mempool_destroy(eq->pool);
+unlock:
+ mutex_unlock(&dev->odp_eq_mutex);
+ return err;
+}
+
+static int
+mlx5_ib_odp_destroy_eq(struct mlx5_ib_dev *dev, struct mlx5_ib_pf_eq *eq)
+{
+ int err;
+
+ if (!eq->core)
+ return 0;
+ mlx5_eq_disable(dev->mdev, eq->core, &eq->irq_nb);
+ err = mlx5_eq_destroy_generic(dev->mdev, eq->core);
+ cancel_work_sync(&eq->work);
+ destroy_workqueue(eq->wq);
+ mempool_destroy(eq->pool);
+
+ return err;
+}
+
+void mlx5_odp_init_mkey_cache_entry(struct mlx5_cache_ent *ent)
+{
+ if (!(ent->dev->odp_caps.general_caps & IB_ODP_SUPPORT_IMPLICIT))
+ return;
+
+ switch (ent->order - 2) {
+ case MLX5_IMR_MTT_CACHE_ENTRY:
+ ent->page = PAGE_SHIFT;
+ ent->ndescs = MLX5_IMR_MTT_ENTRIES;
+ ent->access_mode = MLX5_MKC_ACCESS_MODE_MTT;
+ ent->limit = 0;
+ break;
+
+ case MLX5_IMR_KSM_CACHE_ENTRY:
+ ent->page = MLX5_KSM_PAGE_SHIFT;
+ ent->ndescs = mlx5_imr_ksm_entries;
+ ent->access_mode = MLX5_MKC_ACCESS_MODE_KSM;
+ ent->limit = 0;
+ break;
+ }
+}
+
+static const struct ib_device_ops mlx5_ib_dev_odp_ops = {
+ .advise_mr = mlx5_ib_advise_mr,
+};
+
+int mlx5_ib_odp_init_one(struct mlx5_ib_dev *dev)
+{
+ int ret = 0;
+
+ internal_fill_odp_caps(dev);
+
+ if (!(dev->odp_caps.general_caps & IB_ODP_SUPPORT))
+ return ret;
+
+ ib_set_device_ops(&dev->ib_dev, &mlx5_ib_dev_odp_ops);
+
+ if (dev->odp_caps.general_caps & IB_ODP_SUPPORT_IMPLICIT) {
+ ret = mlx5_cmd_null_mkey(dev->mdev, &dev->null_mkey);
+ if (ret) {
+ mlx5_ib_err(dev, "Error getting null_mkey %d\n", ret);
+ return ret;
+ }
+ }
+
+ mutex_init(&dev->odp_eq_mutex);
+ return ret;
+}
+
+void mlx5_ib_odp_cleanup_one(struct mlx5_ib_dev *dev)
+{
+ if (!(dev->odp_caps.general_caps & IB_ODP_SUPPORT))
+ return;
+
+ mlx5_ib_odp_destroy_eq(dev, &dev->odp_pf_eq);
+}
+
+int mlx5_ib_odp_init(void)
+{
+ mlx5_imr_ksm_entries = BIT_ULL(get_order(TASK_SIZE) -
+ MLX5_IMR_MTT_BITS);
+
+ return 0;
+}
+
+struct prefetch_mr_work {
+ struct work_struct work;
+ u32 pf_flags;
+ u32 num_sge;
+ struct {
+ u64 io_virt;
+ struct mlx5_ib_mr *mr;
+ size_t length;
+ } frags[];
+};
+
+static void destroy_prefetch_work(struct prefetch_mr_work *work)
+{
+ u32 i;
+
+ for (i = 0; i < work->num_sge; ++i)
+ mlx5r_deref_odp_mkey(&work->frags[i].mr->mmkey);
+
+ kvfree(work);
+}
+
+static struct mlx5_ib_mr *
+get_prefetchable_mr(struct ib_pd *pd, enum ib_uverbs_advise_mr_advice advice,
+ u32 lkey)
+{
+ struct mlx5_ib_dev *dev = to_mdev(pd->device);
+ struct mlx5_ib_mr *mr = NULL;
+ struct mlx5_ib_mkey *mmkey;
+
+ xa_lock(&dev->odp_mkeys);
+ mmkey = xa_load(&dev->odp_mkeys, mlx5_base_mkey(lkey));
+ if (!mmkey || mmkey->key != lkey) {
+ mr = ERR_PTR(-ENOENT);
+ goto end;
+ }
+ if (mmkey->type != MLX5_MKEY_MR) {
+ mr = ERR_PTR(-EINVAL);
+ goto end;
+ }
+
+ mr = container_of(mmkey, struct mlx5_ib_mr, mmkey);
+
+ if (mr->ibmr.pd != pd) {
+ mr = ERR_PTR(-EPERM);
+ goto end;
+ }
+
+ /* prefetch with write-access must be supported by the MR */
+ if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE &&
+ !mr->umem->writable) {
+ mr = ERR_PTR(-EPERM);
+ goto end;
+ }
+
+ refcount_inc(&mmkey->usecount);
+end:
+ xa_unlock(&dev->odp_mkeys);
+ return mr;
+}
+
+static void mlx5_ib_prefetch_mr_work(struct work_struct *w)
+{
+ struct prefetch_mr_work *work =
+ container_of(w, struct prefetch_mr_work, work);
+ u32 bytes_mapped = 0;
+ int ret;
+ u32 i;
+
+ /* We rely on IB/core that work is executed if we have num_sge != 0 only. */
+ WARN_ON(!work->num_sge);
+ for (i = 0; i < work->num_sge; ++i) {
+ ret = pagefault_mr(work->frags[i].mr, work->frags[i].io_virt,
+ work->frags[i].length, &bytes_mapped,
+ work->pf_flags);
+ if (ret <= 0)
+ continue;
+ mlx5_update_odp_stats(work->frags[i].mr, prefetch, ret);
+ }
+
+ destroy_prefetch_work(work);
+}
+
+static int 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)
+{
+ u32 i;
+
+ INIT_WORK(&work->work, mlx5_ib_prefetch_mr_work);
+ work->pf_flags = pf_flags;
+
+ for (i = 0; i < num_sge; ++i) {
+ struct mlx5_ib_mr *mr;
+
+ mr = get_prefetchable_mr(pd, advice, sg_list[i].lkey);
+ if (IS_ERR(mr)) {
+ work->num_sge = i;
+ return PTR_ERR(mr);
+ }
+ work->frags[i].io_virt = sg_list[i].addr;
+ work->frags[i].length = sg_list[i].length;
+ work->frags[i].mr = mr;
+ }
+ work->num_sge = num_sge;
+ return 0;
+}
+
+static int 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)
+{
+ u32 bytes_mapped = 0;
+ int ret = 0;
+ u32 i;
+
+ for (i = 0; i < num_sge; ++i) {
+ struct mlx5_ib_mr *mr;
+
+ mr = get_prefetchable_mr(pd, advice, sg_list[i].lkey);
+ if (IS_ERR(mr))
+ return PTR_ERR(mr);
+ ret = pagefault_mr(mr, sg_list[i].addr, sg_list[i].length,
+ &bytes_mapped, pf_flags);
+ if (ret < 0) {
+ mlx5r_deref_odp_mkey(&mr->mmkey);
+ return ret;
+ }
+ mlx5_update_odp_stats(mr, prefetch, ret);
+ mlx5r_deref_odp_mkey(&mr->mmkey);
+ }
+
+ return 0;
+}
+
+int 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)
+{
+ u32 pf_flags = 0;
+ struct prefetch_mr_work *work;
+ int rc;
+
+ if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH)
+ pf_flags |= MLX5_PF_FLAGS_DOWNGRADE;
+
+ if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_NO_FAULT)
+ pf_flags |= MLX5_PF_FLAGS_SNAPSHOT;
+
+ if (flags & IB_UVERBS_ADVISE_MR_FLAG_FLUSH)
+ return mlx5_ib_prefetch_sg_list(pd, advice, pf_flags, sg_list,
+ num_sge);
+
+ work = kvzalloc(struct_size(work, frags, num_sge), GFP_KERNEL);
+ if (!work)
+ return -ENOMEM;
+
+ rc = init_prefetch_work(pd, advice, pf_flags, work, sg_list, num_sge);
+ if (rc) {
+ destroy_prefetch_work(work);
+ return rc;
+ }
+ queue_work(system_unbound_wq, &work->work);
+ return 0;
+}