LXR linux/include/rdma/ib

   1/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
   2/*
   3 * Copyright (c) 2007 Cisco Systems.  All rights reserved.
   4 * Copyright (c) 2020 Intel Corporation.  All rights reserved.
   5 */
   6
   7#ifndef IB_UMEM_H
   8#define IB_UMEM_H
   9
  10#include <linux/list.h>
  11#include <linux/scatterlist.h>
  12#include <linux/workqueue.h>
  13#include <rdma/ib_verbs.h>
  14
  15struct ib_ucontext;
  16struct ib_umem_odp;
  17struct dma_buf_attach_ops;
  18
  19struct ib_umem {
  20        struct ib_device       *ibdev;
  21        struct mm_struct       *owning_mm;
  22        u64 iova;
  23        size_t                  length;
  24        unsigned long           address;
  25        u32 writable : 1;
  26        u32 is_odp : 1;
  27        u32 is_dmabuf : 1;
  28        struct work_struct      work;
  29        struct sg_append_table sgt_append;
  30};
  31
  32struct ib_umem_dmabuf {
  33        struct ib_umem umem;
  34        struct dma_buf_attachment *attach;
  35        struct sg_table *sgt;
  36        struct scatterlist *first_sg;
  37        struct scatterlist *last_sg;
  38        unsigned long first_sg_offset;
  39        unsigned long last_sg_trim;
  40        void *private;
  41};
  42
  43static inline struct ib_umem_dmabuf *to_ib_umem_dmabuf(struct ib_umem *umem)
  44{
  45        return container_of(umem, struct ib_umem_dmabuf, umem);
  46}
  47
  48/* Returns the offset of the umem start relative to the first page. */
  49static inline int ib_umem_offset(struct ib_umem *umem)
  50{
  51        return umem->address & ~PAGE_MASK;
  52}
  53
  54static inline unsigned long ib_umem_dma_offset(struct ib_umem *umem,
  55                                               unsigned long pgsz)
  56{
  57        return (sg_dma_address(umem->sgt_append.sgt.sgl) + ib_umem_offset(umem)) &
  58               (pgsz - 1);
  59}
  60
  61static inline size_t ib_umem_num_dma_blocks(struct ib_umem *umem,
  62                                            unsigned long pgsz)
  63{
  64        return (size_t)((ALIGN(umem->iova + umem->length, pgsz) -
  65                         ALIGN_DOWN(umem->iova, pgsz))) /
  66               pgsz;
  67}
  68
  69static inline size_t ib_umem_num_pages(struct ib_umem *umem)
  70{
  71        return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
  72}
  73
  74static inline void __rdma_umem_block_iter_start(struct ib_block_iter *biter,
  75                                                struct ib_umem *umem,
  76                                                unsigned long pgsz)
  77{
  78        __rdma_block_iter_start(biter, umem->sgt_append.sgt.sgl,
  79                                umem->sgt_append.sgt.nents, pgsz);
  80}
  81
  82/**
  83 * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
  84 * @umem: umem to iterate over
  85 * @pgsz: Page size to split the list into
  86 *
  87 * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
  88 * returned DMA blocks will be aligned to pgsz and span the range:
  89 * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
  90 *
  91 * Performs exactly ib_umem_num_dma_blocks() iterations.
  92 */
  93#define rdma_umem_for_each_dma_block(umem, biter, pgsz)                        \
  94        for (__rdma_umem_block_iter_start(biter, umem, pgsz);                  \
  95             __rdma_block_iter_next(biter);)
  96
  97#ifdef CONFIG_INFINIBAND_USER_MEM
  98
  99struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
 100                            size_t size, int access);
 101void ib_umem_release(struct ib_umem *umem);
 102int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
 103                      size_t length);
 104unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 105                                     unsigned long pgsz_bitmap,
 106                                     unsigned long virt);
 107
 108/**
 109 * ib_umem_find_best_pgoff - Find best HW page size
 110 *
 111 * @umem: umem struct
 112 * @pgsz_bitmap bitmap of HW supported page sizes
 113 * @pgoff_bitmask: Mask of bits that can be represented with an offset
 114 *
 115 * This is very similar to ib_umem_find_best_pgsz() except instead of accepting
 116 * an IOVA it accepts a bitmask specifying what address bits can be represented
 117 * with a page offset.
 118 *
 119 * For instance if the HW has multiple page sizes, requires 64 byte alignemnt,
 120 * and can support aligned offsets up to 4032 then pgoff_bitmask would be
 121 * "111111000000".
 122 *
 123 * If the pgoff_bitmask requires either alignment in the low bit or an
 124 * unavailable page size for the high bits, this function returns 0.
 125 */
 126static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
 127                                                    unsigned long pgsz_bitmap,
 128                                                    u64 pgoff_bitmask)
 129{
 130        struct scatterlist *sg = umem->sgt_append.sgt.sgl;
 131        dma_addr_t dma_addr;
 132
 133        dma_addr = sg_dma_address(sg) + (umem->address & ~PAGE_MASK);
 134        return ib_umem_find_best_pgsz(umem, pgsz_bitmap,
 135                                      dma_addr & pgoff_bitmask);
 136}
 137
 138struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
 139                                          unsigned long offset, size_t size,
 140                                          int fd, int access,
 141                                          const struct dma_buf_attach_ops *ops);
 142int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
 143void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
 144void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
 145
 146#else /* CONFIG_INFINIBAND_USER_MEM */
 147
 148#include <linux/err.h>
 149
 150static inline struct ib_umem *ib_umem_get(struct ib_device *device,
 151                                          unsigned long addr, size_t size,
 152                                          int access)
 153{
 154        return ERR_PTR(-EOPNOTSUPP);
 155}
 156static inline void ib_umem_release(struct ib_umem *umem) { }
 157static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
 158                                    size_t length) {
 159        return -EOPNOTSUPP;
 160}
 161static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 162                                                   unsigned long pgsz_bitmap,
 163                                                   unsigned long virt)
 164{
 165        return 0;
 166}
 167static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
 168                                                    unsigned long pgsz_bitmap,
 169                                                    u64 pgoff_bitmask)
 170{
 171        return 0;
 172}
 173static inline
 174struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
 175                                          unsigned long offset,
 176                                          size_t size, int fd,
 177                                          int access,
 178                                          struct dma_buf_attach_ops *ops)
 179{
 180        return ERR_PTR(-EOPNOTSUPP);
 181}
 182static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
 183{
 184        return -EOPNOTSUPP;
 185}
 186static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { }
 187static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { }
 188
 189#endif /* CONFIG_INFINIBAND_USER_MEM */
 190#endif /* IB_UMEM_H */
 191