drivers/infiniband/hw/mlx5/mem.c

   1 /*
   2  * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #include <linux/module.h>
  34 #include <rdma/ib_umem.h>
  35 #include <rdma/ib_umem_odp.h>
  36 #include "mlx5_ib.h"
  37
  38 /* @umem: umem object to scan
  39  * @addr: ib virtual address requested by the user
  40  * @max_page_shift: high limit for page_shift - 0 means no limit
  41  * @count: number of PAGE_SIZE pages covered by umem
  42  * @shift: page shift for the compound pages found in the region
  43  * @ncont: number of compund pages
  44  * @order: log2 of the number of compound pages
  45  */
  46 void mlx5_ib_cont_pages(struct ib_umem *umem, u64 addr,
  47                         unsigned long max_page_shift,
  48                         int *count, int *shift,
  49                         int *ncont, int *order)
  50 {
  51         unsigned long tmp;
  52         unsigned long m;
  53         u64 base = ~0, p = 0;
  54         u64 len, pfn;
  55         int i = 0;
  56         struct scatterlist *sg;
  57         int entry;
  58         unsigned long page_shift = umem->page_shift;
  59
  60         if (umem->odp_data) {
  61                 *ncont = ib_umem_page_count(umem);
  62                 *count = *ncont << (page_shift - PAGE_SHIFT);
  63                 *shift = page_shift;
  64                 if (order)
  65                         *order = ilog2(roundup_pow_of_two(*ncont));
  66
  67                 return;
  68         }
  69
  70         addr = addr >> page_shift;
  71         tmp = (unsigned long)addr;
  72         m = find_first_bit(&tmp, BITS_PER_LONG);
  73         if (max_page_shift)
  74                 m = min_t(unsigned long, max_page_shift - page_shift, m);
  75
  76         for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
  77                 len = sg_dma_len(sg) >> page_shift;
  78                 pfn = sg_dma_address(sg) >> page_shift;
  79                 if (base + p != pfn) {
  80                         /* If either the offset or the new
  81                          * base are unaligned update m
  82                          */
  83                         tmp = (unsigned long)(pfn | p);
  84                         if (!IS_ALIGNED(tmp, 1 << m))
  85                                 m = find_first_bit(&tmp, BITS_PER_LONG);
  86
  87                         base = pfn;
  88                         p = 0;
  89                 }
  90
  91                 p += len;
  92                 i += len;
  93         }
  94
  95         if (i) {
  96                 m = min_t(unsigned long, ilog2(roundup_pow_of_two(i)), m);
  97
  98                 if (order)
  99                         *order = ilog2(roundup_pow_of_two(i) >> m);
 100
 101                 *ncont = DIV_ROUND_UP(i, (1 << m));
 102         } else {
 103                 m  = 0;
 104
 105                 if (order)
 106                         *order = 0;
 107
 108                 *ncont = 0;
 109         }
 110         *shift = page_shift + m;
 111         *count = i;
 112 }
 113
 114 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
 115 static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
 116 {
 117         u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
 118
 119         if (umem_dma & ODP_READ_ALLOWED_BIT)
 120                 mtt_entry |= MLX5_IB_MTT_READ;
 121         if (umem_dma & ODP_WRITE_ALLOWED_BIT)
 122                 mtt_entry |= MLX5_IB_MTT_WRITE;
 123
 124         return mtt_entry;
 125 }
 126 #endif
 127
 128 /*
 129  * Populate the given array with bus addresses from the umem.
 130  *
 131  * dev - mlx5_ib device
 132  * umem - umem to use to fill the pages
 133  * page_shift - determines the page size used in the resulting array
 134  * offset - offset into the umem to start from,
 135  *          only implemented for ODP umems
 136  * num_pages - total number of pages to fill
 137  * pas - bus addresses array to fill
 138  * access_flags - access flags to set on all present pages.
 139                   use enum mlx5_ib_mtt_access_flags for this.
 140  */
 141 void __mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
 142                             int page_shift, size_t offset, size_t num_pages,
 143                             __be64 *pas, int access_flags)
 144 {
 145         unsigned long umem_page_shift = umem->page_shift;
 146         int shift = page_shift - umem_page_shift;
 147         int mask = (1 << shift) - 1;
 148         int i, k, idx;
 149         u64 cur = 0;
 150         u64 base;
 151         int len;
 152         struct scatterlist *sg;
 153         int entry;
 154 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
 155         const bool odp = umem->odp_data != NULL;
 156
 157         if (odp) {
 158                 WARN_ON(shift != 0);
 159                 WARN_ON(access_flags != (MLX5_IB_MTT_READ | MLX5_IB_MTT_WRITE));
 160
 161                 for (i = 0; i < num_pages; ++i) {
 162                         dma_addr_t pa = umem->odp_data->dma_list[offset + i];
 163
 164                         pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
 165                 }
 166                 return;
 167         }
 168 #endif
 169
 170         i = 0;
 171         for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
 172                 len = sg_dma_len(sg) >> umem_page_shift;
 173                 base = sg_dma_address(sg);
 174
 175                 /* Skip elements below offset */
 176                 if (i + len < offset << shift) {
 177                         i += len;
 178                         continue;
 179                 }
 180
 181                 /* Skip pages below offset */
 182                 if (i < offset << shift) {
 183                         k = (offset << shift) - i;
 184                         i = offset << shift;
 185                 } else {
 186                         k = 0;
 187                 }
 188
 189                 for (; k < len; k++) {
 190                         if (!(i & mask)) {
 191                                 cur = base + (k << umem_page_shift);
 192                                 cur |= access_flags;
 193                                 idx = (i >> shift) - offset;
 194
 195                                 pas[idx] = cpu_to_be64(cur);
 196                                 mlx5_ib_dbg(dev, "pas[%d] 0x%llx\n",
 197                                             i >> shift, be64_to_cpu(pas[idx]));
 198                         }
 199                         i++;
 200
 201                         /* Stop after num_pages reached */
 202                         if (i >> shift >= offset + num_pages)
 203                                 return;
 204                 }
 205         }
 206 }
 207
 208 void mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
 209                           int page_shift, __be64 *pas, int access_flags)
 210 {
 211         return __mlx5_ib_populate_pas(dev, umem, page_shift, 0,
 212                                       ib_umem_num_pages(umem), pas,
 213                                       access_flags);
 214 }
 215 int mlx5_ib_get_buf_offset(u64 addr, int page_shift, u32 *offset)
 216 {
 217         u64 page_size;
 218         u64 page_mask;
 219         u64 off_size;
 220         u64 off_mask;
 221         u64 buf_off;
 222
 223         page_size = (u64)1 << page_shift;
 224         page_mask = page_size - 1;
 225         buf_off = addr & page_mask;
 226         off_size = page_size >> 6;
 227         off_mask = off_size - 1;
 228
 229         if (buf_off & off_mask)
 230                 return -EINVAL;
 231
 232         *offset = buf_off >> ilog2(off_size);
 233         return 0;
 234 }