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        if (ibmr) {
  82                if (fmr->fmr)
  83                        ib_dealloc_fmr(fmr->fmr);
  84                kfree(ibmr);
  85        }
  86        atomic_dec(&pool->item_count);
  87        return ERR_PTR(err);
  88}
  89
  90int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev, struct rds_ib_mr *ibmr,
  91                   struct scatterlist *sg, unsigned int nents)
  92{
  93        struct ib_device *dev = rds_ibdev->dev;
  94        struct rds_ib_fmr *fmr = &ibmr->u.fmr;
  95        struct scatterlist *scat = sg;
  96        u64 io_addr = 0;
  97        u64 *dma_pages;
  98        u32 len;
  99        int page_cnt, sg_dma_len;
 100        int i, j;
 101        int ret;
 102
 103        sg_dma_len = ib_dma_map_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 104        if (unlikely(!sg_dma_len)) {
 105                pr_warn("RDS/IB: %s failed!\n", __func__);
 106                return -EBUSY;
 107        }
 108
 109        len = 0;
 110        page_cnt = 0;
 111
 112        for (i = 0; i < sg_dma_len; ++i) {
 113                unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]);
 114                u64 dma_addr = ib_sg_dma_address(dev, &scat[i]);
 115
 116                if (dma_addr & ~PAGE_MASK) {
 117                        if (i > 0)
 118                                return -EINVAL;
 119                        else
 120                                ++page_cnt;
 121                }
 122                if ((dma_addr + dma_len) & ~PAGE_MASK) {
 123                        if (i < sg_dma_len - 1)
 124                                return -EINVAL;
 125                        else
 126                                ++page_cnt;
 127                }
 128
 129                len += dma_len;
 130        }
 131
 132        page_cnt += len >> PAGE_SHIFT;
 133        if (page_cnt > ibmr->pool->fmr_attr.max_pages)
 134                return -EINVAL;
 135
 136        dma_pages = kmalloc_node(sizeof(u64) * page_cnt, GFP_ATOMIC,
 137                                 rdsibdev_to_node(rds_ibdev));
 138        if (!dma_pages)
 139                return -ENOMEM;
 140
 141        page_cnt = 0;
 142        for (i = 0; i < sg_dma_len; ++i) {
 143                unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]);
 144                u64 dma_addr = ib_sg_dma_address(dev, &scat[i]);
 145
 146                for (j = 0; j < dma_len; j += PAGE_SIZE)
 147                        dma_pages[page_cnt++] =
 148                                (dma_addr & PAGE_MASK) + j;
 149        }
 150
 151        ret = ib_map_phys_fmr(fmr->fmr, dma_pages, page_cnt, io_addr);
 152        if (ret)
 153                goto out;
 154
 155        /* Success - we successfully remapped the MR, so we can
 156         * safely tear down the old mapping.
 157         */
 158        rds_ib_teardown_mr(ibmr);
 159
 160        ibmr->sg = scat;
 161        ibmr->sg_len = nents;
 162        ibmr->sg_dma_len = sg_dma_len;
 163        ibmr->remap_count++;
 164
 165        if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 166                rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
 167        else
 168                rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
 169        ret = 0;
 170
 171out:
 172        kfree(dma_pages);
 173
 174        return ret;
 175}
 176
 177struct rds_ib_mr *rds_ib_reg_fmr(struct rds_ib_device *rds_ibdev,
 178                                 struct scatterlist *sg,
 179                                 unsigned long nents,
 180                                 u32 *key)
 181{
 182        struct rds_ib_mr *ibmr = NULL;
 183        struct rds_ib_fmr *fmr;
 184        int ret;
 185
 186        ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
 187        if (IS_ERR(ibmr))
 188                return ibmr;
 189
 190        ibmr->device = rds_ibdev;
 191        fmr = &ibmr->u.fmr;
 192        ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
 193        if (ret == 0)
 194                *key = fmr->fmr->rkey;
 195        else
 196                rds_ib_free_mr(ibmr, 0);
 197
 198        return ibmr;
 199}
 200
 201void rds_ib_unreg_fmr(struct list_head *list, unsigned int *nfreed,
 202                      unsigned long *unpinned, unsigned int goal)
 203{
 204        struct rds_ib_mr *ibmr, *next;
 205        struct rds_ib_fmr *fmr;
 206        LIST_HEAD(fmr_list);
 207        int ret = 0;
 208        unsigned int freed = *nfreed;
 209
 210        /* String all ib_mr's onto one list and hand them to  ib_unmap_fmr */
 211        list_for_each_entry(ibmr, list, unmap_list) {
 212                fmr = &ibmr->u.fmr;
 213                list_add(&fmr->fmr->list, &fmr_list);
 214        }
 215
 216        ret = ib_unmap_fmr(&fmr_list);
 217        if (ret)
 218                pr_warn("RDS/IB: FMR invalidation failed (err=%d)\n", ret);
 219
 220        /* Now we can destroy the DMA mapping and unpin any pages */
 221        list_for_each_entry_safe(ibmr, next, list, unmap_list) {
 222                fmr = &ibmr->u.fmr;
 223                *unpinned += ibmr->sg_len;
 224                __rds_ib_teardown_mr(ibmr);
 225                if (freed < goal ||
 226                    ibmr->remap_count >= ibmr->pool->fmr_attr.max_maps) {
 227                        if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 228                                rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
 229                        else
 230                                rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
 231                        list_del(&ibmr->unmap_list);
 232                        ib_dealloc_fmr(fmr->fmr);
 233                        kfree(ibmr);
 234                        freed++;
 235                }
 236        }
 237        *nfreed = freed;
 238}
 239
 240void rds_ib_free_fmr_list(struct rds_ib_mr *ibmr)
 241{
 242        struct rds_ib_mr_pool *pool = ibmr->pool;
 243
 244        if (ibmr->remap_count >= pool->fmr_attr.max_maps)
 245                llist_add(&ibmr->llnode, &pool->drop_list);
 246        else
 247                llist_add(&ibmr->llnode, &pool->free_list);
 248}
 249