From 368c0159d492d7fbdb5791b40c9263ec4e97a10f Mon Sep 17 00:00:00 2001 From: Jianxin Xiong Date: Tue, 15 Dec 2020 13:27:13 -0800 Subject: RDMA/umem: Support importing dma-buf as user memory region 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. Link: https://lore.kernel.org/r/1608067636-98073-2-git-send-email-jianxin.xiong@intel.com Signed-off-by: Jianxin Xiong Reviewed-by: Sean Hefty Acked-by: Michael J. Ruhl Acked-by: Christian Koenig Acked-by: Daniel Vetter Signed-off-by: Jason Gunthorpe --- include/rdma/ib_umem.h | 48 +++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 45 insertions(+), 3 deletions(-) (limited to 'include/rdma/ib_umem.h') diff --git a/include/rdma/ib_umem.h b/include/rdma/ib_umem.h index 7752211c9638..676c57f5ca80 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) { @@ -86,6 +105,7 @@ 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); + /** * ib_umem_find_best_pgoff - Find best HW page size * @@ -116,6 +136,14 @@ static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem, dma_addr & pgoff_bitmask); } +struct ib_umem_dmabuf *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 */ #include @@ -124,12 +152,12 @@ static inline struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, size_t size, int access) { - return ERR_PTR(-EINVAL); + return ERR_PTR(-EOPNOTSUPP); } static inline void ib_umem_release(struct ib_umem *umem) { } static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset, size_t length) { - return -EINVAL; + return -EOPNOTSUPP; } static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem, unsigned long pgsz_bitmap, @@ -143,7 +171,21 @@ static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem, { return 0; } +static inline +struct ib_umem_dmabuf *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(-EOPNOTSUPP); +} +static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf) +{ + return -EOPNOTSUPP; +} +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 */ -- cgit v1.2.3