From patchwork Fri Oct 23 16:39:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Xiong, Jianxin" X-Patchwork-Id: 11853921 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4AEA714B2 for ; Fri, 23 Oct 2020 16:26:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2C92822210 for ; Fri, 23 Oct 2020 16:26:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750561AbgJWQ0M (ORCPT ); Fri, 23 Oct 2020 12:26:12 -0400 Received: from mga17.intel.com ([192.55.52.151]:10550 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750451AbgJWQ0M (ORCPT ); Fri, 23 Oct 2020 12:26:12 -0400 IronPort-SDR: puJ2gtOt4d1uN2BbhXREultpcw6EMRQo+c7mNM/vliUE/j4johcLt/jfdWRvpKd22rld+n93kM MfF9LcSIK1KQ== X-IronPort-AV: E=McAfee;i="6000,8403,9782"; a="147556652" X-IronPort-AV: E=Sophos;i="5.77,409,1596524400"; d="scan'208";a="147556652" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Oct 2020 09:26:10 -0700 IronPort-SDR: RwXFhkyN3o44iPFEzeeVbyfMK7kLy3Fl7qOiC/Q3V6rMd6gH8Tyv3LhaLUrXsToI6pKJacVitd BJb20Y2vDl9w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,409,1596524400"; d="scan'208";a="349257185" Received: from cst-dev.jf.intel.com ([10.23.221.69]) by fmsmga004.fm.intel.com with ESMTP; 23 Oct 2020 09:26:10 -0700 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 v6 1/4] RDMA/umem: Support importing dma-buf as user memory region Date: Fri, 23 Oct 2020 09:39:58 -0700 Message-Id: <1603471201-32588-2-git-send-email-jianxin.xiong@intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1603471201-32588-1-git-send-email-jianxin.xiong@intel.com> References: <1603471201-32588-1-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 | 4 + drivers/infiniband/core/umem_dmabuf.c | 197 ++++++++++++++++++++++++++++++++++ drivers/infiniband/core/umem_dmabuf.h | 11 ++ include/rdma/ib_umem.h | 35 +++++- 5 files changed, 247 insertions(+), 2 deletions(-) create mode 100644 drivers/infiniband/core/umem_dmabuf.c create mode 100644 drivers/infiniband/core/umem_dmabuf.h diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile index ccf2670..8ab4eea 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 e9fecbd..2c45525 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 @@ -43,6 +44,7 @@ #include #include "uverbs.h" +#include "umem_dmabuf.h" static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int dirty) { @@ -269,6 +271,8 @@ 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 0000000..66b234d --- /dev/null +++ b/drivers/infiniband/core/umem_dmabuf.c @@ -0,0 +1,197 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* + * Copyright (c) 2020 Intel Corporation. All rights reserved. + */ + +#include +#include +#include + +#include "uverbs.h" +#include "umem_dmabuf.h" + +/* + * Generate a new dma sg list from a sub range of an existing dma sg list. + * Both the input and output have their entries page aligned. + */ +static int ib_umem_dmabuf_sgt_slice(struct sg_table *sgt, u64 offset, + u64 length, struct sg_table *new_sgt) +{ + struct scatterlist *sg, *new_sg; + u64 start, end, off, addr, len; + unsigned int new_nents; + int err; + int i; + + start = ALIGN_DOWN(offset, PAGE_SIZE); + end = ALIGN(offset + length, PAGE_SIZE); + + offset = start; + length = end - start; + new_nents = 0; + for_each_sgtable_dma_sg(sgt, sg, i) { + len = sg_dma_len(sg); + off = min(len, offset); + len -= off; + len = min(len, length); + if (len) + new_nents++; + length -= len; + offset -= off; + } + + err = sg_alloc_table(new_sgt, new_nents, GFP_KERNEL); + if (err) + return err; + + offset = start; + length = end - start; + new_sg = new_sgt->sgl; + for_each_sgtable_dma_sg(sgt, sg, i) { + addr = sg_dma_address(sg); + len = sg_dma_len(sg); + off = min(len, offset); + addr += off; + len -= off; + len = min(len, length); + if (len) { + sg_dma_address(new_sg) = addr; + sg_dma_len(new_sg) = len; + new_sg = sg_next(new_sg); + } + length -= len; + offset -= off; + } + + return 0; +} + +int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf) +{ + struct sg_table *sgt; + struct dma_fence *fence; + int err; + + dma_resv_assert_held(umem_dmabuf->attach->dmabuf->resv); + + sgt = dma_buf_map_attachment(umem_dmabuf->attach, + DMA_BIDIRECTIONAL); + + if (IS_ERR(sgt)) + return PTR_ERR(sgt); + + err = ib_umem_dmabuf_sgt_slice(sgt, umem_dmabuf->umem.address, + umem_dmabuf->umem.length, + &umem_dmabuf->umem.sg_head); + if (err) { + dma_buf_unmap_attachment(umem_dmabuf->attach, sgt, + DMA_BIDIRECTIONAL); + return err; + } + + umem_dmabuf->umem.nmap = umem_dmabuf->umem.sg_head.nents; + 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; + + sg_free_table(&umem_dmabuf->umem.sg_head); + 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; + + if (check_add_overflow(offset, (unsigned long)size, &end)) + return ERR_PTR(-EINVAL); + + if (unlikely(PAGE_ALIGN(end) < PAGE_SIZE)) + return ERR_PTR(-EINVAL); + + if (unlikely(!ops || !ops->move_notify)) + return ERR_PTR(-EINVAL); + +#ifdef CONFIG_DMA_VIRT_OPS + if (device->dma_device->dma_ops == &dma_virt_ops) + return ERR_PTR(-EINVAL); +#endif + + 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->iova = offset; + umem->writable = ib_access_writable(access); + umem->is_dmabuf = 1; + + dmabuf = dma_buf_get(fd); + if (IS_ERR(dmabuf)) { + ret = PTR_ERR(dmabuf); + 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_release_dmabuf; + } + + return umem; + +out_release_dmabuf: + dma_buf_put(dmabuf); + +out_free_umem: + kfree(umem_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_resv_lock(dmabuf->resv, NULL); + ib_umem_dmabuf_unmap_pages(umem_dmabuf); + dma_resv_unlock(dmabuf->resv); + + dma_buf_detach(dmabuf, umem_dmabuf->attach); + dma_buf_put(dmabuf); + kfree(umem_dmabuf); +} diff --git a/drivers/infiniband/core/umem_dmabuf.h b/drivers/infiniband/core/umem_dmabuf.h new file mode 100644 index 0000000..13acf55 --- /dev/null +++ b/drivers/infiniband/core/umem_dmabuf.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */ +/* + * Copyright (c) 2020 Intel Corporation. All rights reserved. + */ + +#ifndef UMEM_DMABUF_H +#define UMEM_DMABUF_H + +void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf); + +#endif /* UMEM_DMABUF_H */ diff --git a/include/rdma/ib_umem.h b/include/rdma/ib_umem.h index 7059750..73a7b19 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 +24,25 @@ 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; + void *device_context; +}; + +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 +94,12 @@ 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); #else /* CONFIG_INFINIBAND_USER_MEM */ @@ -101,7 +122,19 @@ 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) { } #endif /* CONFIG_INFINIBAND_USER_MEM */ - #endif /* IB_UMEM_H */