From patchwork Tue Nov 24 21:35:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Xiong, Jianxin" X-Patchwork-Id: 11929873 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 491FFC64E7A for ; Tue, 24 Nov 2020 21:22:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1A5352086A for ; Tue, 24 Nov 2020 21:22:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731414AbgKXVWB (ORCPT ); Tue, 24 Nov 2020 16:22:01 -0500 Received: from mga09.intel.com ([134.134.136.24]:9288 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731133AbgKXVWB (ORCPT ); Tue, 24 Nov 2020 16:22:01 -0500 IronPort-SDR: b4XLpOE/2YddVO8kgHebrt/xHvGa/wjZeSUjLqtClJ6KZJcyZAi/Lzs4l6CZrPK253J4A7Ie4X vzLyRRTTF/YA== X-IronPort-AV: E=McAfee;i="6000,8403,9815"; a="172175990" X-IronPort-AV: E=Sophos;i="5.78,367,1599548400"; d="scan'208";a="172175990" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Nov 2020 13:21:58 -0800 IronPort-SDR: Vp26P61wkkjR0x5nICxF0i8xu8cboqh8Q/tI/GJ+Q87shurJrnIlu+rW0+QqJtk3OgTDFdAnjX STKMTYiGMCOA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.78,367,1599548400"; d="scan'208";a="343313414" Received: from cst-dev.jf.intel.com ([10.23.221.69]) by orsmga002.jf.intel.com with ESMTP; 24 Nov 2020 13:21:58 -0800 From: Jianxin Xiong To: linux-rdma@vger.kernel.org, dri-devel@lists.freedesktop.org Cc: Jianxin Xiong , Doug Ledford , Jason Gunthorpe , Leon Romanovsky , Sumit Semwal , Christian Koenig , Daniel Vetter Subject: [PATCH v12 1/4] RDMA/umem: Support importing dma-buf as user memory region Date: Tue, 24 Nov 2020 13:35:47 -0800 Message-Id: <1606253750-67057-2-git-send-email-jianxin.xiong@intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1606253750-67057-1-git-send-email-jianxin.xiong@intel.com> References: <1606253750-67057-1-git-send-email-jianxin.xiong@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org Dma-buf is a standard cross-driver buffer sharing mechanism that can be used to support peer-to-peer access from RDMA devices. Device memory exported via dma-buf is associated with a file descriptor. This is passed to the user space as a property associated with the buffer allocation. When the buffer is registered as a memory region, the file descriptor is passed to the RDMA driver along with other parameters. Implement the common code for importing dma-buf object and mapping dma-buf pages. Signed-off-by: Jianxin Xiong Reviewed-by: Sean Hefty Acked-by: Michael J. Ruhl Acked-by: Christian Koenig Acked-by: Daniel Vetter --- drivers/infiniband/core/Makefile | 2 +- drivers/infiniband/core/umem.c | 3 + drivers/infiniband/core/umem_dmabuf.c | 173 ++++++++++++++++++++++++++ include/rdma/ib_umem.h | 41 +++++- 4 files changed, 217 insertions(+), 2 deletions(-) create mode 100644 drivers/infiniband/core/umem_dmabuf.c diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile index ccf2670ef45e..8ab4eea5a0a5 100644 --- a/drivers/infiniband/core/Makefile +++ b/drivers/infiniband/core/Makefile @@ -40,5 +40,5 @@ ib_uverbs-y := uverbs_main.o uverbs_cmd.o uverbs_marshall.o \ uverbs_std_types_srq.o \ uverbs_std_types_wq.o \ uverbs_std_types_qp.o -ib_uverbs-$(CONFIG_INFINIBAND_USER_MEM) += umem.o +ib_uverbs-$(CONFIG_INFINIBAND_USER_MEM) += umem.o umem_dmabuf.o ib_uverbs-$(CONFIG_INFINIBAND_ON_DEMAND_PAGING) += umem_odp.o diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index f1fc7e39c782..a025ce831076 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -2,6 +2,7 @@ * Copyright (c) 2005 Topspin Communications. All rights reserved. * Copyright (c) 2005 Cisco Systems. All rights reserved. * Copyright (c) 2005 Mellanox Technologies. All rights reserved. + * Copyright (c) 2020 Intel Corporation. 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 @@ -278,6 +279,8 @@ void ib_umem_release(struct ib_umem *umem) { if (!umem) return; + if (umem->is_dmabuf) + return ib_umem_dmabuf_release(to_ib_umem_dmabuf(umem)); if (umem->is_odp) return ib_umem_odp_release(to_ib_umem_odp(umem)); diff --git a/drivers/infiniband/core/umem_dmabuf.c b/drivers/infiniband/core/umem_dmabuf.c new file mode 100644 index 000000000000..e50b95555846 --- /dev/null +++ b/drivers/infiniband/core/umem_dmabuf.c @@ -0,0 +1,173 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* + * Copyright (c) 2020 Intel Corporation. All rights reserved. + */ + +#include +#include +#include + +#include "uverbs.h" + +int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf) +{ + struct sg_table *sgt; + struct scatterlist *sg; + struct dma_fence *fence; + unsigned long start, end, cur; + unsigned int nmap; + int i; + + dma_resv_assert_held(umem_dmabuf->attach->dmabuf->resv); + + if (umem_dmabuf->sgt) + return 0; + + sgt = dma_buf_map_attachment(umem_dmabuf->attach, DMA_BIDIRECTIONAL); + if (IS_ERR(sgt)) + return PTR_ERR(sgt); + + /* modify the sg list in-place to match umem address and length */ + + start = ALIGN_DOWN(umem_dmabuf->umem.address, PAGE_SIZE); + end = ALIGN(umem_dmabuf->umem.address + umem_dmabuf->umem.length, + PAGE_SIZE); + cur = 0; + nmap = 0; + for_each_sgtable_dma_sg(sgt, sg, i) { + if (start < cur + sg_dma_len(sg) && cur < end) + nmap++; + if (cur <= start && start < cur + sg_dma_len(sg)) { + unsigned long offset = start - cur; + + umem_dmabuf->first_sg = sg; + umem_dmabuf->first_sg_offset = offset; + sg_dma_address(sg) += offset; + sg_dma_len(sg) -= offset; + cur += offset; + } + if (cur < end && end <= cur + sg_dma_len(sg)) { + unsigned long trim = cur + sg_dma_len(sg) - end; + + umem_dmabuf->last_sg = sg; + umem_dmabuf->last_sg_trim = trim; + sg_dma_len(sg) -= trim; + break; + } + cur += sg_dma_len(sg); + } + + umem_dmabuf->umem.sg_head.sgl = umem_dmabuf->first_sg; + umem_dmabuf->umem.sg_head.nents = nmap; + umem_dmabuf->umem.nmap = nmap; + umem_dmabuf->sgt = sgt; + + /* + * Although the sg list is valid now, the content of the pages + * may be not up-to-date. Wait for the exporter to finish + * the migration. + */ + fence = dma_resv_get_excl(umem_dmabuf->attach->dmabuf->resv); + if (fence) + dma_fence_wait(fence, false); + + return 0; +} +EXPORT_SYMBOL(ib_umem_dmabuf_map_pages); + +void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) +{ + dma_resv_assert_held(umem_dmabuf->attach->dmabuf->resv); + + if (!umem_dmabuf->sgt) + return; + + /* retore the original sg list */ + if (umem_dmabuf->first_sg) { + sg_dma_address(umem_dmabuf->first_sg) -= + umem_dmabuf->first_sg_offset; + sg_dma_len(umem_dmabuf->first_sg) += + umem_dmabuf->first_sg_offset; + umem_dmabuf->first_sg = NULL; + umem_dmabuf->first_sg_offset = 0; + } + if (umem_dmabuf->last_sg) { + sg_dma_len(umem_dmabuf->last_sg) += + umem_dmabuf->last_sg_trim; + umem_dmabuf->last_sg = NULL; + umem_dmabuf->last_sg_trim = 0; + } + + dma_buf_unmap_attachment(umem_dmabuf->attach, umem_dmabuf->sgt, + DMA_BIDIRECTIONAL); + + umem_dmabuf->sgt = NULL; +} +EXPORT_SYMBOL(ib_umem_dmabuf_unmap_pages); + +struct ib_umem *ib_umem_dmabuf_get(struct ib_device *device, + unsigned long offset, size_t size, + int fd, int access, + const struct dma_buf_attach_ops *ops) +{ + struct dma_buf *dmabuf; + struct ib_umem_dmabuf *umem_dmabuf; + struct ib_umem *umem; + unsigned long end; + long ret = -EINVAL; + + if (check_add_overflow(offset, (unsigned long)size, &end)) + return ERR_PTR(-EINVAL); + + if (unlikely(!ops || !ops->move_notify)) + return ERR_PTR(-EINVAL); + + dmabuf = dma_buf_get(fd); + if (IS_ERR(dmabuf)) + return (void *)dmabuf; + + if (dmabuf->size < end) + goto out_release_dmabuf; + + umem_dmabuf = kzalloc(sizeof(*umem_dmabuf), GFP_KERNEL); + if (!umem_dmabuf) + return ERR_PTR(-ENOMEM); + + umem = &umem_dmabuf->umem; + umem->ibdev = device; + umem->length = size; + umem->address = offset; + umem->writable = ib_access_writable(access); + umem->is_dmabuf = 1; + + if (unlikely(!ib_umem_num_pages(umem))) + goto out_free_umem; + + umem_dmabuf->attach = dma_buf_dynamic_attach( + dmabuf, + device->dma_device, + ops, + umem_dmabuf); + if (IS_ERR(umem_dmabuf->attach)) { + ret = PTR_ERR(umem_dmabuf->attach); + goto out_free_umem; + } + return umem; + +out_free_umem: + kfree(umem_dmabuf); + +out_release_dmabuf: + dma_buf_put(dmabuf); + return ERR_PTR(ret); +} +EXPORT_SYMBOL(ib_umem_dmabuf_get); + +void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) +{ + struct dma_buf *dmabuf = umem_dmabuf->attach->dmabuf; + + dma_buf_detach(dmabuf, umem_dmabuf->attach); + dma_buf_put(dmabuf); + kfree(umem_dmabuf); +} diff --git a/include/rdma/ib_umem.h b/include/rdma/ib_umem.h index 70597508c765..48422bc5bb85 100644 --- a/include/rdma/ib_umem.h +++ b/include/rdma/ib_umem.h @@ -1,6 +1,7 @@ /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */ /* * Copyright (c) 2007 Cisco Systems. All rights reserved. + * Copyright (c) 2020 Intel Corporation. All rights reserved. */ #ifndef IB_UMEM_H @@ -13,6 +14,7 @@ struct ib_ucontext; struct ib_umem_odp; +struct dma_buf_attach_ops; struct ib_umem { struct ib_device *ibdev; @@ -22,12 +24,29 @@ struct ib_umem { unsigned long address; u32 writable : 1; u32 is_odp : 1; + u32 is_dmabuf : 1; struct work_struct work; struct sg_table sg_head; int nmap; unsigned int sg_nents; }; +struct ib_umem_dmabuf { + struct ib_umem umem; + struct dma_buf_attachment *attach; + struct sg_table *sgt; + struct scatterlist *first_sg; + struct scatterlist *last_sg; + unsigned long first_sg_offset; + unsigned long last_sg_trim; + void *private; +}; + +static inline struct ib_umem_dmabuf *to_ib_umem_dmabuf(struct ib_umem *umem) +{ + return container_of(umem, struct ib_umem_dmabuf, umem); +} + /* Returns the offset of the umem start relative to the first page. */ static inline int ib_umem_offset(struct ib_umem *umem) { @@ -79,6 +98,13 @@ int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset, unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem, unsigned long pgsz_bitmap, unsigned long virt); +struct ib_umem *ib_umem_dmabuf_get(struct ib_device *device, + unsigned long offset, size_t size, + int fd, int access, + const struct dma_buf_attach_ops *ops); +int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf); +void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf); +void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf); #else /* CONFIG_INFINIBAND_USER_MEM */ @@ -101,7 +127,20 @@ static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem, { return 0; } +static inline struct ib_umem *ib_umem_dmabuf_get(struct ib_device *device, + unsigned long offset, + size_t size, int fd, + int access, + struct dma_buf_attach_ops *ops) +{ + return ERR_PTR(-EINVAL); +} +static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf) +{ + return -EINVAL; +} +static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { } +static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { } #endif /* CONFIG_INFINIBAND_USER_MEM */ - #endif /* IB_UMEM_H */