LXR linux/net/rds/ib

   1/*
   2 * Copyright (c) 2016 Oracle.  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 "ib_mr.h"
  34
  35struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev, int npages)
  36{
  37        struct rds_ib_mr_pool *pool;
  38        struct rds_ib_mr *ibmr = NULL;
  39        struct rds_ib_fmr *fmr;
  40        int err = 0;
  41
  42        if (npages <= RDS_MR_8K_MSG_SIZE)
  43                pool = rds_ibdev->mr_8k_pool;
  44        else
  45                pool = rds_ibdev->mr_1m_pool;
  46
  47        ibmr = rds_ib_try_reuse_ibmr(pool);
  48        if (ibmr)
  49                return ibmr;
  50
  51        ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
  52                            rdsibdev_to_node(rds_ibdev));
  53        if (!ibmr) {
  54                err = -ENOMEM;
  55                goto out_no_cigar;
  56        }
  57
  58        fmr = &ibmr->u.fmr;
  59        fmr->fmr = ib_alloc_fmr(rds_ibdev->pd,
  60                        (IB_ACCESS_LOCAL_WRITE |
  61                         IB_ACCESS_REMOTE_READ |
  62                         IB_ACCESS_REMOTE_WRITE |
  63                         IB_ACCESS_REMOTE_ATOMIC),
  64                        &pool->fmr_attr);
  65        if (IS_ERR(fmr->fmr)) {
  66                err = PTR_ERR(fmr->fmr);
  67                fmr->fmr = NULL;
  68                pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, err);
  69                goto out_no_cigar;
  70        }
  71
  72        ibmr->pool = pool;
  73        if (pool->pool_type == RDS_IB_MR_8K_POOL)
  74                rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
  75        else
  76                rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);
  77
  78        return ibmr;
  79
  80out_no_cigar:
  81        kfree(ibmr);
  82        atomic_dec(&pool->item_count);
  83
  84        return ERR_PTR(err);
  85}
  86
  87static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev,
  88                          struct rds_ib_mr *ibmr, struct scatterlist *sg,
  89                          unsigned int nents)
  90{
  91        struct ib_device *dev = rds_ibdev->dev;
  92        struct rds_ib_fmr *fmr = &ibmr->u.fmr;
  93        struct scatterlist *scat = sg;
  94        u64 io_addr = 0;
  95        u64 *dma_pages;
  96        u32 len;
  97        int page_cnt, sg_dma_len;
  98        int i, j;
  99        int ret;
 100
 101        sg_dma_len = ib_dma_map_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 102        if (unlikely(!sg_dma_len)) {
 103                pr_warn("RDS/IB: %s failed!\n", __func__);
 104                return -EBUSY;
 105        }
 106
 107        len = 0;
 108        page_cnt = 0;
 109
 110        for (i = 0; i < sg_dma_len; ++i) {
 111                unsigned int dma_len = sg_dma_len(&scat[i]);
 112                u64 dma_addr = sg_dma_address(&scat[i]);
 113
 114                if (dma_addr & ~PAGE_MASK) {
 115                        if (i > 0) {
 116                                ib_dma_unmap_sg(dev, sg, nents,
 117                                                DMA_BIDIRECTIONAL);
 118                                return -EINVAL;
 119                        } else {
 120                                ++page_cnt;
 121                        }
 122                }
 123                if ((dma_addr + dma_len) & ~PAGE_MASK) {
 124                        if (i < sg_dma_len - 1) {
 125                                ib_dma_unmap_sg(dev, sg, nents,
 126                                                DMA_BIDIRECTIONAL);
 127                                return -EINVAL;
 128                        } else {
 129                                ++page_cnt;
 130                        }
 131                }
 132
 133                len += dma_len;
 134        }
 135
 136        page_cnt += len >> PAGE_SHIFT;
 137        if (page_cnt > ibmr->pool->fmr_attr.max_pages) {
 138                ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 139                return -EINVAL;
 140        }
 141
 142        dma_pages = kmalloc_array_node(sizeof(u64), page_cnt, GFP_ATOMIC,
 143                                       rdsibdev_to_node(rds_ibdev));
 144        if (!dma_pages) {
 145                ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 146                return -ENOMEM;
 147        }
 148
 149        page_cnt = 0;
 150        for (i = 0; i < sg_dma_len; ++i) {
 151                unsigned int dma_len = sg_dma_len(&scat[i]);
 152                u64 dma_addr = sg_dma_address(&scat[i]);
 153
 154                for (j = 0; j < dma_len; j += PAGE_SIZE)
 155                        dma_pages[page_cnt++] =
 156                                (dma_addr & PAGE_MASK) + j;
 157        }
 158
 159        ret = ib_map_phys_fmr(fmr->fmr, dma_pages, page_cnt, io_addr);
 160        if (ret) {
 161                ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 162                goto out;
 163        }
 164
 165        /* Success - we successfully remapped the MR, so we can
 166         * safely tear down the old mapping.
 167         */
 168        rds_ib_teardown_mr(ibmr);
 169
 170        ibmr->sg = scat;
 171        ibmr->sg_len = nents;
 172        ibmr->sg_dma_len = sg_dma_len;
 173        ibmr->remap_count++;
 174
 175        if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 176                rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
 177        else
 178                rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
 179        ret = 0;
 180
 181out:
 182        kfree(dma_pages);
 183
 184        return ret;
 185}
 186
 187struct rds_ib_mr *rds_ib_reg_fmr(struct rds_ib_device *rds_ibdev,
 188                                 struct scatterlist *sg,
 189                                 unsigned long nents,
 190                                 u32 *key)
 191{
 192        struct rds_ib_mr *ibmr = NULL;
 193        struct rds_ib_fmr *fmr;
 194        int ret;
 195
 196        ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
 197        if (IS_ERR(ibmr))
 198                return ibmr;
 199
 200        ibmr->device = rds_ibdev;
 201        fmr = &ibmr->u.fmr;
 202        ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
 203        if (ret == 0)
 204                *key = fmr->fmr->rkey;
 205        else
 206                rds_ib_free_mr(ibmr, 0);
 207
 208        return ibmr;
 209}
 210
 211void rds_ib_unreg_fmr(struct list_head *list, unsigned int *nfreed,
 212                      unsigned long *unpinned, unsigned int goal)
 213{
 214        struct rds_ib_mr *ibmr, *next;
 215        struct rds_ib_fmr *fmr;
 216        LIST_HEAD(fmr_list);
 217        int ret = 0;
 218        unsigned int freed = *nfreed;
 219
 220        /* String all ib_mr's onto one list and hand them to  ib_unmap_fmr */
 221        list_for_each_entry(ibmr, list, unmap_list) {
 222                fmr = &ibmr->u.fmr;
 223                list_add(&fmr->fmr->list, &fmr_list);
 224        }
 225
 226        ret = ib_unmap_fmr(&fmr_list);
 227        if (ret)
 228                pr_warn("RDS/IB: FMR invalidation failed (err=%d)\n", ret);
 229
 230        /* Now we can destroy the DMA mapping and unpin any pages */
 231        list_for_each_entry_safe(ibmr, next, list, unmap_list) {
 232                fmr = &ibmr->u.fmr;
 233                *unpinned += ibmr->sg_len;
 234                __rds_ib_teardown_mr(ibmr);
 235                if (freed < goal ||
 236                    ibmr->remap_count >= ibmr->pool->fmr_attr.max_maps) {
 237                        if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 238                                rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
 239                        else
 240                                rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
 241                        list_del(&ibmr->unmap_list);
 242                        ib_dealloc_fmr(fmr->fmr);
 243                        kfree(ibmr);
 244                        freed++;
 245                }
 246        }
 247        *nfreed = freed;
 248}
 249
 250void rds_ib_free_fmr_list(struct rds_ib_mr *ibmr)
 251{
 252        struct rds_ib_mr_pool *pool = ibmr->pool;
 253
 254        if (ibmr->remap_count >= pool->fmr_attr.max_maps)
 255                llist_add(&ibmr->llnode, &pool->drop_list);
 256        else
 257                llist_add(&ibmr->llnode, &pool->free_list);
 258}
 259