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 */
   5
   6#ifndef IB_UMEM_H
   7#define IB_UMEM_H
   8
   9#include <linux/list.h>
  10#include <linux/scatterlist.h>
  11#include <linux/workqueue.h>
  12#include <rdma/ib_verbs.h>
  13
  14struct ib_ucontext;
  15struct ib_umem_odp;
  16
  17struct ib_umem {
  18        struct ib_device       *ibdev;
  19        struct mm_struct       *owning_mm;
  20        u64 iova;
  21        size_t                  length;
  22        unsigned long           address;
  23        u32 writable : 1;
  24        u32 is_odp : 1;
  25        struct work_struct      work;
  26        struct sg_table sg_head;
  27        int             nmap;
  28        unsigned int    sg_nents;
  29};
  30
  31/* Returns the offset of the umem start relative to the first page. */
  32static inline int ib_umem_offset(struct ib_umem *umem)
  33{
  34        return umem->address & ~PAGE_MASK;
  35}
  36
  37static inline size_t ib_umem_num_dma_blocks(struct ib_umem *umem,
  38                                            unsigned long pgsz)
  39{
  40        return (size_t)((ALIGN(umem->iova + umem->length, pgsz) -
  41                         ALIGN_DOWN(umem->iova, pgsz))) /
  42               pgsz;
  43}
  44
  45static inline size_t ib_umem_num_pages(struct ib_umem *umem)
  46{
  47        return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
  48}
  49
  50static inline void __rdma_umem_block_iter_start(struct ib_block_iter *biter,
  51                                                struct ib_umem *umem,
  52                                                unsigned long pgsz)
  53{
  54        __rdma_block_iter_start(biter, umem->sg_head.sgl, umem->nmap, pgsz);
  55}
  56
  57/**
  58 * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
  59 * @umem: umem to iterate over
  60 * @pgsz: Page size to split the list into
  61 *
  62 * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
  63 * returned DMA blocks will be aligned to pgsz and span the range:
  64 * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
  65 *
  66 * Performs exactly ib_umem_num_dma_blocks() iterations.
  67 */
  68#define rdma_umem_for_each_dma_block(umem, biter, pgsz)                        \
  69        for (__rdma_umem_block_iter_start(biter, umem, pgsz);                  \
  70             __rdma_block_iter_next(biter);)
  71
  72#ifdef CONFIG_INFINIBAND_USER_MEM
  73
  74struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
  75                            size_t size, int access);
  76void ib_umem_release(struct ib_umem *umem);
  77int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
  78                      size_t length);
  79unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
  80                                     unsigned long pgsz_bitmap,
  81                                     unsigned long virt);
  82
  83#else /* CONFIG_INFINIBAND_USER_MEM */
  84
  85#include <linux/err.h>
  86
  87static inline struct ib_umem *ib_umem_get(struct ib_device *device,
  88                                          unsigned long addr, size_t size,
  89                                          int access)
  90{
  91        return ERR_PTR(-EINVAL);
  92}
  93static inline void ib_umem_release(struct ib_umem *umem) { }
  94static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
  95                                    size_t length) {
  96        return -EINVAL;
  97}
  98static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
  99                                                   unsigned long pgsz_bitmap,
 100                                                   unsigned long virt)
 101{
 102        return 0;
 103}
 104
 105#endif /* CONFIG_INFINIBAND_USER_MEM */
 106
 107#endif /* IB_UMEM_H */
 108