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        u8 pinned : 1;
  42};
  43
  44static inline struct ib_umem_dmabuf *to_ib_umem_dmabuf(struct ib_umem *umem)
  45{
  46        return container_of(umem, struct ib_umem_dmabuf, umem);
  47}
  48
  49/* Returns the offset of the umem start relative to the first page. */
  50static inline int ib_umem_offset(struct ib_umem *umem)
  51{
  52        return umem->address & ~PAGE_MASK;
  53}
  54
  55static inline unsigned long ib_umem_dma_offset(struct ib_umem *umem,
  56                                               unsigned long pgsz)
  57{
  58        return (sg_dma_address(umem->sgt_append.sgt.sgl) + ib_umem_offset(umem)) &
  59               (pgsz - 1);
  60}
  61
  62static inline size_t ib_umem_num_dma_blocks(struct ib_umem *umem,
  63                                            unsigned long pgsz)
  64{
  65        return (size_t)((ALIGN(umem->iova + umem->length, pgsz) -
  66                         ALIGN_DOWN(umem->iova, pgsz))) /
  67               pgsz;
  68}
  69
  70static inline size_t ib_umem_num_pages(struct ib_umem *umem)
  71{
  72        return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
  73}
  74
  75static inline void __rdma_umem_block_iter_start(struct ib_block_iter *biter,
  76                                                struct ib_umem *umem,
  77                                                unsigned long pgsz)
  78{
  79        __rdma_block_iter_start(biter, umem->sgt_append.sgt.sgl,
  80                                umem->sgt_append.sgt.nents, pgsz);
  81}
  82
  83/**
  84 * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
  85 * @umem: umem to iterate over
  86 * @pgsz: Page size to split the list into
  87 *
  88 * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
  89 * returned DMA blocks will be aligned to pgsz and span the range:
  90 * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
  91 *
  92 * Performs exactly ib_umem_num_dma_blocks() iterations.
  93 */
  94#define rdma_umem_for_each_dma_block(umem, biter, pgsz)                        \
  95        for (__rdma_umem_block_iter_start(biter, umem, pgsz);                  \
  96             __rdma_block_iter_next(biter);)
  97
  98#ifdef CONFIG_INFINIBAND_USER_MEM
  99
 100struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
 101                            size_t size, int access);
 102void ib_umem_release(struct ib_umem *umem);
 103int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
 104                      size_t length);
 105unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 106                                     unsigned long pgsz_bitmap,
 107                                     unsigned long virt);
 108
 109/**
 110 * ib_umem_find_best_pgoff - Find best HW page size
 111 *
 112 * @umem: umem struct
 113 * @pgsz_bitmap bitmap of HW supported page sizes
 114 * @pgoff_bitmask: Mask of bits that can be represented with an offset
 115 *
 116 * This is very similar to ib_umem_find_best_pgsz() except instead of accepting
 117 * an IOVA it accepts a bitmask specifying what address bits can be represented
 118 * with a page offset.
 119 *
 120 * For instance if the HW has multiple page sizes, requires 64 byte alignemnt,
 121 * and can support aligned offsets up to 4032 then pgoff_bitmask would be
 122 * "111111000000".
 123 *
 124 * If the pgoff_bitmask requires either alignment in the low bit or an
 125 * unavailable page size for the high bits, this function returns 0.
 126 */
 127static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
 128                                                    unsigned long pgsz_bitmap,
 129                                                    u64 pgoff_bitmask)
 130{
 131        struct scatterlist *sg = umem->sgt_append.sgt.sgl;
 132        dma_addr_t dma_addr;
 133
 134        dma_addr = sg_dma_address(sg) + (umem->address & ~PAGE_MASK);
 135        return ib_umem_find_best_pgsz(umem, pgsz_bitmap,
 136                                      dma_addr & pgoff_bitmask);
 137}
 138
 139struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
 140                                          unsigned long offset, size_t size,
 141                                          int fd, int access,
 142                                          const struct dma_buf_attach_ops *ops);
 143struct ib_umem_dmabuf *ib_umem_dmabuf_get_pinned(struct ib_device *device,
 144                                                 unsigned long offset,
 145                                                 size_t size, int fd,
 146                                                 int access);
 147int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
 148void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
 149void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
 150
 151#else /* CONFIG_INFINIBAND_USER_MEM */
 152
 153#include <linux/err.h>
 154
 155static inline struct ib_umem *ib_umem_get(struct ib_device *device,
 156                                          unsigned long addr, size_t size,
 157                                          int access)
 158{
 159        return ERR_PTR(-EOPNOTSUPP);
 160}
 161static inline void ib_umem_release(struct ib_umem *umem) { }
 162static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
 163                                    size_t length) {
 164        return -EOPNOTSUPP;
 165}
 166static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 167                                                   unsigned long pgsz_bitmap,
 168                                                   unsigned long virt)
 169{
 170        return 0;
 171}
 172static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
 173                                                    unsigned long pgsz_bitmap,
 174                                                    u64 pgoff_bitmask)
 175{
 176        return 0;
 177}
 178static inline
 179struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
 180                                          unsigned long offset,
 181                                          size_t size, int fd,
 182                                          int access,
 183                                          struct dma_buf_attach_ops *ops)
 184{
 185        return ERR_PTR(-EOPNOTSUPP);
 186}
 187static inline struct ib_umem_dmabuf *
 188ib_umem_dmabuf_get_pinned(struct ib_device *device, unsigned long offset,
 189                          size_t size, int fd, int access)
 190{
 191        return ERR_PTR(-EOPNOTSUPP);
 192}
 193static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
 194{
 195        return -EOPNOTSUPP;
 196}
 197static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { }
 198static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { }
 199
 200#endif /* CONFIG_INFINIBAND_USER_MEM */
 201#endif /* IB_UMEM_H */
 202