diff options
Diffstat (limited to 'drivers/infiniband/hw/mlx5/odp.c')
| -rw-r--r-- | drivers/infiniband/hw/mlx5/odp.c | 798 |
1 files changed, 798 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c new file mode 100644 index 000000000000..a2c541c4809a --- /dev/null +++ b/drivers/infiniband/hw/mlx5/odp.c @@ -0,0 +1,798 @@ +/* + * Copyright (c) 2014 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.h> +#include <rdma/ib_umem_odp.h> + +#include "mlx5_ib.h" + +#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 + +struct workqueue_struct *mlx5_ib_page_fault_wq; + +void mlx5_ib_invalidate_range(struct ib_umem *umem, unsigned long start, + unsigned long end) +{ + struct mlx5_ib_mr *mr; + const u64 umr_block_mask = (MLX5_UMR_MTT_ALIGNMENT / sizeof(u64)) - 1; + u64 idx = 0, blk_start_idx = 0; + int in_block = 0; + u64 addr; + + if (!umem || !umem->odp_data) { + pr_err("invalidation called on NULL umem or non-ODP umem\n"); + return; + } + + mr = umem->odp_data->private; + + if (!mr || !mr->ibmr.pd) + return; + + start = max_t(u64, ib_umem_start(umem), start); + end = min_t(u64, ib_umem_end(umem), 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 += (u64)umem->page_size) { + idx = (addr - ib_umem_start(umem)) / PAGE_SIZE; + /* + * 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_data->dma_list[idx] & + (ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT)) { + if (!in_block) { + blk_start_idx = idx; + in_block = 1; + } + } else { + u64 umr_offset = idx & umr_block_mask; + + if (in_block && umr_offset == 0) { + mlx5_ib_update_mtt(mr, blk_start_idx, + idx - blk_start_idx, 1); + in_block = 0; + } + } + } + if (in_block) + mlx5_ib_update_mtt(mr, blk_start_idx, idx - blk_start_idx + 1, + 1); + + /* + * 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, start, end); +} + +#define COPY_ODP_BIT_MLX_TO_IB(reg, ib_caps, field_name, bit_name) do { \ + if (be32_to_cpu(reg.field_name) & MLX5_ODP_SUPPORT_##bit_name) \ + ib_caps->field_name |= IB_ODP_SUPPORT_##bit_name; \ +} while (0) + +int mlx5_ib_internal_query_odp_caps(struct mlx5_ib_dev *dev) +{ + int err; + struct mlx5_odp_caps hw_caps; + struct ib_odp_caps *caps = &dev->odp_caps; + + memset(caps, 0, sizeof(*caps)); + + if (!(dev->mdev->caps.gen.flags & MLX5_DEV_CAP_FLAG_ON_DMND_PG)) + return 0; + + err = mlx5_query_odp_caps(dev->mdev, &hw_caps); + if (err) + goto out; + + caps->general_caps = IB_ODP_SUPPORT; + COPY_ODP_BIT_MLX_TO_IB(hw_caps, caps, per_transport_caps.ud_odp_caps, + SEND); + COPY_ODP_BIT_MLX_TO_IB(hw_caps, caps, per_transport_caps.rc_odp_caps, + SEND); + COPY_ODP_BIT_MLX_TO_IB(hw_caps, caps, per_transport_caps.rc_odp_caps, + RECV); + COPY_ODP_BIT_MLX_TO_IB(hw_caps, caps, per_transport_caps.rc_odp_caps, + WRITE); + COPY_ODP_BIT_MLX_TO_IB(hw_caps, caps, per_transport_caps.rc_odp_caps, + READ); + +out: + return err; +} + +static struct mlx5_ib_mr *mlx5_ib_odp_find_mr_lkey(struct mlx5_ib_dev *dev, + u32 key) +{ + u32 base_key = mlx5_base_mkey(key); + struct mlx5_core_mr *mmr = __mlx5_mr_lookup(dev->mdev, base_key); + struct mlx5_ib_mr *mr = container_of(mmr, struct mlx5_ib_mr, mmr); + + if (!mmr || mmr->key != key || !mr->live) + return NULL; + + return container_of(mmr, struct mlx5_ib_mr, mmr); +} + +static void mlx5_ib_page_fault_resume(struct mlx5_ib_qp *qp, + struct mlx5_ib_pfault *pfault, + int error) { + struct mlx5_ib_dev *dev = to_mdev(qp->ibqp.pd->device); + int ret = mlx5_core_page_fault_resume(dev->mdev, qp->mqp.qpn, + pfault->mpfault.flags, + error); + if (ret) + pr_err("Failed to resolve the page fault on QP 0x%x\n", + qp->mqp.qpn); +} + +/* + * Handle a single data segment in a page-fault WQE. + * + * Returns number of pages retrieved on success. The caller will 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 and possibly move the QP to an error state. + * On other errors the QP should also be closed with an error. + */ +static int pagefault_single_data_segment(struct mlx5_ib_qp *qp, + struct mlx5_ib_pfault *pfault, + u32 key, u64 io_virt, size_t bcnt, + u32 *bytes_mapped) +{ + struct mlx5_ib_dev *mib_dev = to_mdev(qp->ibqp.pd->device); + int srcu_key; + unsigned int current_seq; + u64 start_idx; + int npages = 0, ret = 0; + struct mlx5_ib_mr *mr; + u64 access_mask = ODP_READ_ALLOWED_BIT; + + srcu_key = srcu_read_lock(&mib_dev->mr_srcu); + mr = mlx5_ib_odp_find_mr_lkey(mib_dev, key); + /* + * If we didn't find the MR, it means the MR was closed while we were + * handling the ODP event. In this case we return -EFAULT so that the + * QP will be closed. + */ + if (!mr || !mr->ibmr.pd) { + pr_err("Failed to find relevant mr for lkey=0x%06x, probably the MR was destroyed\n", + key); + ret = -EFAULT; + goto srcu_unlock; + } + if (!mr->umem->odp_data) { + pr_debug("skipping non ODP MR (lkey=0x%06x) in page fault handler.\n", + key); + if (bytes_mapped) + *bytes_mapped += + (bcnt - pfault->mpfault.bytes_committed); + goto srcu_unlock; + } + if (mr->ibmr.pd != qp->ibqp.pd) { + pr_err("Page-fault with different PDs for QP and MR.\n"); + ret = -EFAULT; + goto srcu_unlock; + } + + current_seq = ACCESS_ONCE(mr->umem->odp_data->notifiers_seq); + /* + * Ensure the sequence number is valid for some time before we call + * gup. + */ + smp_rmb(); + + /* + * Avoid branches - this code will perform correctly + * in all iterations (in iteration 2 and above, + * bytes_committed == 0). + */ + io_virt += pfault->mpfault.bytes_committed; + bcnt -= pfault->mpfault.bytes_committed; + + start_idx = (io_virt - (mr->mmr.iova & PAGE_MASK)) >> PAGE_SHIFT; + + if (mr->umem->writable) + access_mask |= ODP_WRITE_ALLOWED_BIT; + npages = ib_umem_odp_map_dma_pages(mr->umem, io_virt, bcnt, + access_mask, current_seq); + if (npages < 0) { + ret = npages; + goto srcu_unlock; + } + + if (npages > 0) { + mutex_lock(&mr->umem->odp_data->umem_mutex); + if (!ib_umem_mmu_notifier_retry(mr->umem, current_seq)) { + /* + * No need to check whether the MTTs really belong to + * this MR, since ib_umem_odp_map_dma_pages already + * checks this. + */ + ret = mlx5_ib_update_mtt(mr, start_idx, npages, 0); + } else { + ret = -EAGAIN; + } + mutex_unlock(&mr->umem->odp_data->umem_mutex); + if (ret < 0) { + if (ret != -EAGAIN) + pr_err("Failed to update mkey page tables\n"); + goto srcu_unlock; + } + + if (bytes_mapped) { + u32 new_mappings = npages * PAGE_SIZE - + (io_virt - round_down(io_virt, PAGE_SIZE)); + *bytes_mapped += min_t(u32, new_mappings, bcnt); + } + } + +srcu_unlock: + if (ret == -EAGAIN) { + if (!mr->umem->odp_data->dying) { + struct ib_umem_odp *odp_data = mr->umem->odp_data; + unsigned long timeout = + msecs_to_jiffies(MMU_NOTIFIER_TIMEOUT); + + if (!wait_for_completion_timeout( + &odp_data->notifier_completion, + timeout)) { + pr_warn("timeout waiting for mmu notifier completion\n"); + } + } else { + /* The MR is being killed, kill the QP as well. */ + ret = -EFAULT; + } + } + srcu_read_unlock(&mib_dev->mr_srcu, srcu_key); + pfault->mpfault.bytes_committed = 0; + return ret ? ret : npages; +} + +/** + * Parse a series of data segments for page fault handling. + * + * @qp the QP on which the fault occurred. + * @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). + * + * 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_qp *qp, + struct mlx5_ib_pfault *pfault, void *wqe, + void *wqe_end, u32 *bytes_mapped, + u32 *total_wqe_bytes, int receive_queue) +{ + int ret = 0, npages = 0; + u64 io_virt; + u32 key; + u32 byte_count; + size_t bcnt; + int inline_segment; + + /* Skip SRQ next-WQE segment. */ + if (receive_queue && qp->ibqp.srq) + wqe += sizeof(struct mlx5_wqe_srq_next_seg); + + 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->mpfault.bytes_committed); + } + + /* A zero length data segment designates a length of 2GB. */ + if (bcnt == 0) + bcnt = 1U << 31; + + if (inline_segment || bcnt <= pfault->mpfault.bytes_committed) { + pfault->mpfault.bytes_committed -= + min_t(size_t, bcnt, + pfault->mpfault.bytes_committed); + continue; + } + + ret = pagefault_single_data_segment(qp, pfault, key, io_virt, + bcnt, 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_qp *qp, struct mlx5_ib_pfault *pfault, + void **wqe, void **wqe_end, int wqe_length) +{ + struct mlx5_ib_dev *dev = to_mdev(qp->ibqp.pd->device); + struct mlx5_wqe_ctrl_seg *ctrl = *wqe; + u16 wqe_index = pfault->mpfault.wqe.wqe_index; + unsigned ds, opcode; +#if defined(DEBUG) + u32 ctrl_wqe_index, ctrl_qpn; +#endif + + 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, qp->mqp.qpn); + return -EFAULT; + } + +#if defined(DEBUG) + ctrl_wqe_index = (be32_to_cpu(ctrl->opmod_idx_opcode) & + MLX5_WQE_CTRL_WQE_INDEX_MASK) >> + MLX5_WQE_CTRL_WQE_INDEX_SHIFT; + if (wqe_index != ctrl_wqe_index) { + mlx5_ib_err(dev, "Got WQE with invalid wqe_index. wqe_index=0x%x, qpn=0x%x ctrl->wqe_index=0x%x\n", + wqe_index, qp->mqp.qpn, + ctrl_wqe_index); + return -EFAULT; + } + + ctrl_qpn = (be32_to_cpu(ctrl->qpn_ds) & MLX5_WQE_CTRL_QPN_MASK) >> + MLX5_WQE_CTRL_QPN_SHIFT; + if (qp->mqp.qpn != ctrl_qpn) { + mlx5_ib_err(dev, "Got WQE with incorrect QP number. wqe_index=0x%x, qpn=0x%x ctrl->qpn=0x%x\n", + wqe_index, qp->mqp.qpn, + ctrl_qpn); + return -EFAULT; + } +#endif /* DEBUG */ + + *wqe_end = *wqe + ds * MLX5_WQE_DS_UNITS; + *wqe += sizeof(*ctrl); + + opcode = be32_to_cpu(ctrl->opmod_idx_opcode) & + MLX5_WQE_CTRL_OPCODE_MASK; + switch (qp->ibqp.qp_type) { + case IB_QPT_RC: + switch (opcode) { + case MLX5_OPCODE_SEND: + case MLX5_OPCODE_SEND_IMM: + case MLX5_OPCODE_SEND_INVAL: + if (!(dev->odp_caps.per_transport_caps.rc_odp_caps & + IB_ODP_SUPPORT_SEND)) + goto invalid_transport_or_opcode; + break; + case MLX5_OPCODE_RDMA_WRITE: + case MLX5_OPCODE_RDMA_WRITE_IMM: + if (!(dev->odp_caps.per_transport_caps.rc_odp_caps & + IB_ODP_SUPPORT_WRITE)) + goto invalid_transport_or_opcode; + *wqe += sizeof(struct mlx5_wqe_raddr_seg); + break; + case MLX5_OPCODE_RDMA_READ: + if (!(dev->odp_caps.per_transport_caps.rc_odp_caps & + IB_ODP_SUPPORT_READ)) + goto invalid_transport_or_opcode; + *wqe += sizeof(struct mlx5_wqe_raddr_seg); + break; + default: + goto invalid_transport_or_opcode; + } + break; + case IB_QPT_UD: + switch (opcode) { + case MLX5_OPCODE_SEND: + case MLX5_OPCODE_SEND_IMM: + if (!(dev->odp_caps.per_transport_caps.ud_odp_caps & + IB_ODP_SUPPORT_SEND)) + goto invalid_transport_or_opcode; + *wqe += sizeof(struct mlx5_wqe_datagram_seg); + break; + default: + goto invalid_transport_or_opcode; + } + break; + default: +invalid_transport_or_opcode: + mlx5_ib_err(dev, "ODP fault on QP of an unsupported opcode or transport. transport: 0x%x opcode: 0x%x.\n", + qp->ibqp.qp_type, opcode); + return -EFAULT; + } + + return 0; +} + +/* + * Parse responder 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_responder_pfault_handler( + struct mlx5_ib_qp *qp, struct mlx5_ib_pfault *pfault, + void **wqe, void **wqe_end, int wqe_length) +{ + struct mlx5_ib_dev *dev = to_mdev(qp->ibqp.pd->device); + struct mlx5_ib_wq *wq = &qp->rq; + int wqe_size = 1 << wq->wqe_shift; + + if (qp->ibqp.srq) { + mlx5_ib_err(dev, "ODP fault on SRQ is not supported\n"); + return -EFAULT; + } + + if (qp->wq_sig) { + 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; + } + + switch (qp->ibqp.qp_type) { + case IB_QPT_RC: + if (!(dev->odp_caps.per_transport_caps.rc_odp_caps & + IB_ODP_SUPPORT_RECV)) + goto invalid_transport_or_opcode; + break; + default: +invalid_transport_or_opcode: + mlx5_ib_err(dev, "ODP fault on QP of an unsupported transport. transport: 0x%x\n", + qp->ibqp.qp_type); + return -EFAULT; + } + + *wqe_end = *wqe + wqe_size; + + return 0; +} + +static void mlx5_ib_mr_wqe_pfault_handler(struct mlx5_ib_qp *qp, + struct mlx5_ib_pfault *pfault) +{ + struct mlx5_ib_dev *dev = to_mdev(qp->ibqp.pd->device); + int ret; + void *wqe, *wqe_end; + u32 bytes_mapped, total_wqe_bytes; + char *buffer = NULL; + int resume_with_error = 0; + u16 wqe_index = pfault->mpfault.wqe.wqe_index; + int requestor = pfault->mpfault.flags & MLX5_PFAULT_REQUESTOR; + + buffer = (char *)__get_free_page(GFP_KERNEL); + if (!buffer) { + mlx5_ib_err(dev, "Error allocating memory for IO page fault handling.\n"); + resume_with_error = 1; + goto resolve_page_fault; + } + + ret = mlx5_ib_read_user_wqe(qp, requestor, wqe_index, buffer, + PAGE_SIZE); + if (ret < 0) { + mlx5_ib_err(dev, "Failed reading a WQE following page fault, error=%x, wqe_index=%x, qpn=%x\n", + -ret, wqe_index, qp->mqp.qpn); + resume_with_error = 1; + goto resolve_page_fault; + } + + wqe = buffer; + if (requestor) + ret = mlx5_ib_mr_initiator_pfault_handler(qp, pfault, &wqe, + &wqe_end, ret); + else + ret = mlx5_ib_mr_responder_pfault_handler(qp, pfault, &wqe, + &wqe_end, ret); + if (ret < 0) { + resume_with_error = 1; + goto resolve_page_fault; + } + + if (wqe >= wqe_end) { + mlx5_ib_err(dev, "ODP fault on invalid WQE.\n"); + resume_with_error = 1; + goto resolve_page_fault; + } + + ret = pagefault_data_segments(qp, pfault, wqe, wqe_end, &bytes_mapped, + &total_wqe_bytes, !requestor); + if (ret == -EAGAIN) { + goto resolve_page_fault; + } else if (ret < 0 || total_wqe_bytes > bytes_mapped) { + mlx5_ib_err(dev, "Error getting user pages for page fault. Error: 0x%x\n", + -ret); + resume_with_error = 1; + goto resolve_page_fault; + } + +resolve_page_fault: + mlx5_ib_page_fault_resume(qp, pfault, resume_with_error); + mlx5_ib_dbg(dev, "PAGE FAULT completed. QP 0x%x resume_with_error=%d, flags: 0x%x\n", + qp->mqp.qpn, resume_with_error, pfault->mpfault.flags); + + free_page((unsigned long)buffer); +} + +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_qp *qp, + struct mlx5_ib_pfault *pfault) +{ + struct mlx5_pagefault *mpfault = &pfault->mpfault; + u64 address; + u32 length; + u32 prefetch_len = mpfault->bytes_committed; + int prefetch_activated = 0; + u32 rkey = mpfault->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 */ + struct mlx5_ib_pfault dummy_pfault = {}; + + dummy_pfault.mpfault.bytes_committed = 0; + + mpfault->rdma.rdma_va += mpfault->bytes_committed; + mpfault->rdma.rdma_op_len -= min(mpfault->bytes_committed, + mpfault->rdma.rdma_op_len); + mpfault->bytes_committed = 0; + + address = mpfault->rdma.rdma_va; + length = mpfault->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 = mpfault->rdma.packet_size; + prefetch_len = min(MAX_PREFETCH_LEN, prefetch_len); + } + + ret = pagefault_single_data_segment(qp, pfault, rkey, address, length, + 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(qp, pfault, 1); + return; + } + + mlx5_ib_page_fault_resume(qp, pfault, 0); + + /* 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) { + ret = pagefault_single_data_segment(qp, &dummy_pfault, rkey, + address, + prefetch_len, + NULL); + if (ret < 0) { + pr_warn("Prefetch failed (ret = %d, prefetch_activated = %d) for QPN %d, address: 0x%.16llx, length = 0x%.16x\n", + ret, prefetch_activated, + qp->ibqp.qp_num, address, prefetch_len); + } + } +} + +void mlx5_ib_mr_pfault_handler(struct mlx5_ib_qp *qp, + struct mlx5_ib_pfault *pfault) +{ + u8 event_subtype = pfault->mpfault.event_subtype; + + switch (event_subtype) { + case MLX5_PFAULT_SUBTYPE_WQE: + mlx5_ib_mr_wqe_pfault_handler(qp, pfault); + break; + case MLX5_PFAULT_SUBTYPE_RDMA: + mlx5_ib_mr_rdma_pfault_handler(qp, pfault); + break; + default: + pr_warn("Invalid page fault event subtype: 0x%x\n", + event_subtype); + mlx5_ib_page_fault_resume(qp, pfault, 1); + break; + } +} + +static void mlx5_ib_qp_pfault_action(struct work_struct *work) +{ + struct mlx5_ib_pfault *pfault = container_of(work, + struct mlx5_ib_pfault, + work); + enum mlx5_ib_pagefault_context context = + mlx5_ib_get_pagefault_context(&pfault->mpfault); + struct mlx5_ib_qp *qp = container_of(pfault, struct mlx5_ib_qp, + pagefaults[context]); + mlx5_ib_mr_pfault_handler(qp, pfault); +} + +void mlx5_ib_qp_disable_pagefaults(struct mlx5_ib_qp *qp) +{ + unsigned long flags; + + spin_lock_irqsave(&qp->disable_page_faults_lock, flags); + qp->disable_page_faults = 1; + spin_unlock_irqrestore(&qp->disable_page_faults_lock, flags); + + /* + * Note that at this point, we are guarenteed that no more + * work queue elements will be posted to the work queue with + * the QP we are closing. + */ + flush_workqueue(mlx5_ib_page_fault_wq); +} + +void mlx5_ib_qp_enable_pagefaults(struct mlx5_ib_qp *qp) +{ + unsigned long flags; + + spin_lock_irqsave(&qp->disable_page_faults_lock, flags); + qp->disable_page_faults = 0; + spin_unlock_irqrestore(&qp->disable_page_faults_lock, flags); +} + +static void mlx5_ib_pfault_handler(struct mlx5_core_qp *qp, + struct mlx5_pagefault *pfault) +{ + /* + * Note that we will only get one fault event per QP per context + * (responder/initiator, read/write), until we resolve the page fault + * with the mlx5_ib_page_fault_resume command. Since this function is + * called from within the work element, there is no risk of missing + * events. + */ + struct mlx5_ib_qp *mibqp = to_mibqp(qp); + enum mlx5_ib_pagefault_context context = + mlx5_ib_get_pagefault_context(pfault); + struct mlx5_ib_pfault *qp_pfault = &mibqp->pagefaults[context]; + + qp_pfault->mpfault = *pfault; + + /* No need to stop interrupts here since we are in an interrupt */ + spin_lock(&mibqp->disable_page_faults_lock); + if (!mibqp->disable_page_faults) + queue_work(mlx5_ib_page_fault_wq, &qp_pfault->work); + spin_unlock(&mibqp->disable_page_faults_lock); +} + +void mlx5_ib_odp_create_qp(struct mlx5_ib_qp *qp) +{ + int i; + + qp->disable_page_faults = 1; + spin_lock_init(&qp->disable_page_faults_lock); + + qp->mqp.pfault_handler = mlx5_ib_pfault_handler; + + for (i = 0; i < MLX5_IB_PAGEFAULT_CONTEXTS; ++i) + INIT_WORK(&qp->pagefaults[i].work, mlx5_ib_qp_pfault_action); +} + +int mlx5_ib_odp_init_one(struct mlx5_ib_dev *ibdev) +{ + int ret; + + ret = init_srcu_struct(&ibdev->mr_srcu); + if (ret) + return ret; + + return 0; +} + +void mlx5_ib_odp_remove_one(struct mlx5_ib_dev *ibdev) +{ + cleanup_srcu_struct(&ibdev->mr_srcu); +} + +int __init mlx5_ib_odp_init(void) +{ + mlx5_ib_page_fault_wq = + create_singlethread_workqueue("mlx5_ib_page_faults"); + if (!mlx5_ib_page_fault_wq) + return -ENOMEM; + + return 0; +} + +void mlx5_ib_odp_cleanup(void) +{ + destroy_workqueue(mlx5_ib_page_fault_wq); +} |