include/rdma/ib_umem.h

   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
  15 struct ib_ucontext;
  16 struct ib_umem_odp;
  17 struct dma_buf_attach_ops;
  18
  19 struct 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 sg_append_table sgt_append;
  29 };
  30
  31 struct ib_umem_dmabuf {
  32         struct ib_umem umem;
  33         struct dma_buf_attachment *attach;
  34         struct sg_table *sgt;
  35         struct scatterlist *first_sg;
  36         struct scatterlist *last_sg;
  37         unsigned long first_sg_offset;
  38         unsigned long last_sg_trim;
  39         void *private;
  40         u8 pinned : 1;
  41 };
  42
  43 static 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. */
  49 static inline int ib_umem_offset(struct ib_umem *umem)
  50 {
  51         return umem->address & ~PAGE_MASK;
  52 }
  53
  54 static 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
  61 static 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
  69 static inline size_t ib_umem_num_pages(struct ib_umem *umem)
  70 {
  71         return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
  72 }
  73
  74 static 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         biter->__sg_advance = ib_umem_offset(umem) & ~(pgsz - 1);
  81         biter->__sg_numblocks = ib_umem_num_dma_blocks(umem, pgsz);
  82 }
  83
  84 static inline bool __rdma_umem_block_iter_next(struct ib_block_iter *biter)
  85 {
  86         return __rdma_block_iter_next(biter) && biter->__sg_numblocks--;
  87 }
  88
  89 /**
  90  * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
  91  * @umem: umem to iterate over
  92  * @pgsz: Page size to split the list into
  93  *
  94  * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
  95  * returned DMA blocks will be aligned to pgsz and span the range:
  96  * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
  97  *
  98  * Performs exactly ib_umem_num_dma_blocks() iterations.
  99  */
 100 #define rdma_umem_for_each_dma_block(umem, biter, pgsz)                        \
 101         for (__rdma_umem_block_iter_start(biter, umem, pgsz);                  \
 102              __rdma_umem_block_iter_next(biter);)
 103
 104 #ifdef CONFIG_INFINIBAND_USER_MEM
 105
 106 struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
 107                             size_t size, int access);
 108 void ib_umem_release(struct ib_umem *umem);
 109 int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
 110                       size_t length);
 111 unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 112                                      unsigned long pgsz_bitmap,
 113                                      unsigned long virt);
 114
 115 /**
 116  * ib_umem_find_best_pgoff - Find best HW page size
 117  *
 118  * @umem: umem struct
 119  * @pgsz_bitmap bitmap of HW supported page sizes
 120  * @pgoff_bitmask: Mask of bits that can be represented with an offset
 121  *
 122  * This is very similar to ib_umem_find_best_pgsz() except instead of accepting
 123  * an IOVA it accepts a bitmask specifying what address bits can be represented
 124  * with a page offset.
 125  *
 126  * For instance if the HW has multiple page sizes, requires 64 byte alignemnt,
 127  * and can support aligned offsets up to 4032 then pgoff_bitmask would be
 128  * "111111000000".
 129  *
 130  * If the pgoff_bitmask requires either alignment in the low bit or an
 131  * unavailable page size for the high bits, this function returns 0.
 132  */
 133 static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
 134                                                     unsigned long pgsz_bitmap,
 135                                                     u64 pgoff_bitmask)
 136 {
 137         struct scatterlist *sg = umem->sgt_append.sgt.sgl;
 138         dma_addr_t dma_addr;
 139
 140         dma_addr = sg_dma_address(sg) + (umem->address & ~PAGE_MASK);
 141         return ib_umem_find_best_pgsz(umem, pgsz_bitmap,
 142                                       dma_addr & pgoff_bitmask);
 143 }
 144
 145 struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
 146                                           unsigned long offset, size_t size,
 147                                           int fd, int access,
 148                                           const struct dma_buf_attach_ops *ops);
 149 struct ib_umem_dmabuf *ib_umem_dmabuf_get_pinned(struct ib_device *device,
 150                                                  unsigned long offset,
 151                                                  size_t size, int fd,
 152                                                  int access);
 153 int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
 154 void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
 155 void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
 156
 157 #else /* CONFIG_INFINIBAND_USER_MEM */
 158
 159 #include <linux/err.h>
 160
 161 static inline struct ib_umem *ib_umem_get(struct ib_device *device,
 162                                           unsigned long addr, size_t size,
 163                                           int access)
 164 {
 165         return ERR_PTR(-EOPNOTSUPP);
 166 }
 167 static inline void ib_umem_release(struct ib_umem *umem) { }
 168 static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
 169                                     size_t length) {
 170         return -EOPNOTSUPP;
 171 }
 172 static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 173                                                    unsigned long pgsz_bitmap,
 174                                                    unsigned long virt)
 175 {
 176         return 0;
 177 }
 178 static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
 179                                                     unsigned long pgsz_bitmap,
 180                                                     u64 pgoff_bitmask)
 181 {
 182         return 0;
 183 }
 184 static inline
 185 struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
 186                                           unsigned long offset,
 187                                           size_t size, int fd,
 188                                           int access,
 189                                           struct dma_buf_attach_ops *ops)
 190 {
 191         return ERR_PTR(-EOPNOTSUPP);
 192 }
 193 static inline struct ib_umem_dmabuf *
 194 ib_umem_dmabuf_get_pinned(struct ib_device *device, unsigned long offset,
 195                           size_t size, int fd, int access)
 196 {
 197         return ERR_PTR(-EOPNOTSUPP);
 198 }
 199 static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
 200 {
 201         return -EOPNOTSUPP;
 202 }
 203 static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { }
 204 static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { }
 205
 206 #endif /* CONFIG_INFINIBAND_USER_MEM */
 207 #endif /* IB_UMEM_H */