net/rds/ib_frmr.c

   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
  35 static struct rds_ib_mr *rds_ib_alloc_frmr(struct rds_ib_device *rds_ibdev,
  36                                            int npages)
  37 {
  38         struct rds_ib_mr_pool *pool;
  39         struct rds_ib_mr *ibmr = NULL;
  40         struct rds_ib_frmr *frmr;
  41         int err = 0;
  42
  43         if (npages <= RDS_MR_8K_MSG_SIZE)
  44                 pool = rds_ibdev->mr_8k_pool;
  45         else
  46                 pool = rds_ibdev->mr_1m_pool;
  47
  48         ibmr = rds_ib_try_reuse_ibmr(pool);
  49         if (ibmr)
  50                 return ibmr;
  51
  52         ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
  53                             rdsibdev_to_node(rds_ibdev));
  54         if (!ibmr) {
  55                 err = -ENOMEM;
  56                 goto out_no_cigar;
  57         }
  58
  59         frmr = &ibmr->u.frmr;
  60         frmr->mr = ib_alloc_mr(rds_ibdev->pd, IB_MR_TYPE_MEM_REG,
  61                          pool->fmr_attr.max_pages);
  62         if (IS_ERR(frmr->mr)) {
  63                 pr_warn("RDS/IB: %s failed to allocate MR", __func__);
  64                 goto out_no_cigar;
  65         }
  66
  67         ibmr->pool = pool;
  68         if (pool->pool_type == RDS_IB_MR_8K_POOL)
  69                 rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
  70         else
  71                 rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);
  72
  73         if (atomic_read(&pool->item_count) > pool->max_items_soft)
  74                 pool->max_items_soft = pool->max_items;
  75
  76         frmr->fr_state = FRMR_IS_FREE;
  77         return ibmr;
  78
  79 out_no_cigar:
  80         kfree(ibmr);
  81         atomic_dec(&pool->item_count);
  82         return ERR_PTR(err);
  83 }
  84
  85 static void rds_ib_free_frmr(struct rds_ib_mr *ibmr, bool drop)
  86 {
  87         struct rds_ib_mr_pool *pool = ibmr->pool;
  88
  89         if (drop)
  90                 llist_add(&ibmr->llnode, &pool->drop_list);
  91         else
  92                 llist_add(&ibmr->llnode, &pool->free_list);
  93         atomic_add(ibmr->sg_len, &pool->free_pinned);
  94         atomic_inc(&pool->dirty_count);
  95
  96         /* If we've pinned too many pages, request a flush */
  97         if (atomic_read(&pool->free_pinned) >= pool->max_free_pinned ||
  98             atomic_read(&pool->dirty_count) >= pool->max_items / 5)
  99                 queue_delayed_work(rds_ib_mr_wq, &pool->flush_worker, 10);
 100 }
 101
 102 static int rds_ib_post_reg_frmr(struct rds_ib_mr *ibmr)
 103 {
 104         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 105         struct ib_send_wr *failed_wr;
 106         struct ib_reg_wr reg_wr;
 107         int ret;
 108
 109         while (atomic_dec_return(&ibmr->ic->i_fastreg_wrs) <= 0) {
 110                 atomic_inc(&ibmr->ic->i_fastreg_wrs);
 111                 cpu_relax();
 112         }
 113
 114         ret = ib_map_mr_sg_zbva(frmr->mr, ibmr->sg, ibmr->sg_len, 0, PAGE_SIZE);
 115         if (unlikely(ret != ibmr->sg_len))
 116                 return ret < 0 ? ret : -EINVAL;
 117
 118         /* Perform a WR for the fast_reg_mr. Each individual page
 119          * in the sg list is added to the fast reg page list and placed
 120          * inside the fast_reg_mr WR.  The key used is a rolling 8bit
 121          * counter, which should guarantee uniqueness.
 122          */
 123         ib_update_fast_reg_key(frmr->mr, ibmr->remap_count++);
 124         frmr->fr_state = FRMR_IS_INUSE;
 125
 126         memset(&reg_wr, 0, sizeof(reg_wr));
 127         reg_wr.wr.wr_id = (unsigned long)(void *)ibmr;
 128         reg_wr.wr.opcode = IB_WR_REG_MR;
 129         reg_wr.wr.num_sge = 0;
 130         reg_wr.mr = frmr->mr;
 131         reg_wr.key = frmr->mr->rkey;
 132         reg_wr.access = IB_ACCESS_LOCAL_WRITE |
 133                         IB_ACCESS_REMOTE_READ |
 134                         IB_ACCESS_REMOTE_WRITE;
 135         reg_wr.wr.send_flags = IB_SEND_SIGNALED;
 136
 137         failed_wr = &reg_wr.wr;
 138         ret = ib_post_send(ibmr->ic->i_cm_id->qp, &reg_wr.wr, &failed_wr);
 139         WARN_ON(failed_wr != &reg_wr.wr);
 140         if (unlikely(ret)) {
 141                 /* Failure here can be because of -ENOMEM as well */
 142                 frmr->fr_state = FRMR_IS_STALE;
 143                 atomic_inc(&ibmr->ic->i_fastreg_wrs);
 144                 if (printk_ratelimit())
 145                         pr_warn("RDS/IB: %s returned error(%d)\n",
 146                                 __func__, ret);
 147         }
 148         return ret;
 149 }
 150
 151 static int rds_ib_map_frmr(struct rds_ib_device *rds_ibdev,
 152                            struct rds_ib_mr_pool *pool,
 153                            struct rds_ib_mr *ibmr,
 154                            struct scatterlist *sg, unsigned int sg_len)
 155 {
 156         struct ib_device *dev = rds_ibdev->dev;
 157         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 158         int i;
 159         u32 len;
 160         int ret = 0;
 161
 162         /* We want to teardown old ibmr values here and fill it up with
 163          * new sg values
 164          */
 165         rds_ib_teardown_mr(ibmr);
 166
 167         ibmr->sg = sg;
 168         ibmr->sg_len = sg_len;
 169         ibmr->sg_dma_len = 0;
 170         frmr->sg_byte_len = 0;
 171         WARN_ON(ibmr->sg_dma_len);
 172         ibmr->sg_dma_len = ib_dma_map_sg(dev, ibmr->sg, ibmr->sg_len,
 173                                          DMA_BIDIRECTIONAL);
 174         if (unlikely(!ibmr->sg_dma_len)) {
 175                 pr_warn("RDS/IB: %s failed!\n", __func__);
 176                 return -EBUSY;
 177         }
 178
 179         frmr->sg_byte_len = 0;
 180         frmr->dma_npages = 0;
 181         len = 0;
 182
 183         ret = -EINVAL;
 184         for (i = 0; i < ibmr->sg_dma_len; ++i) {
 185                 unsigned int dma_len = ib_sg_dma_len(dev, &ibmr->sg[i]);
 186                 u64 dma_addr = ib_sg_dma_address(dev, &ibmr->sg[i]);
 187
 188                 frmr->sg_byte_len += dma_len;
 189                 if (dma_addr & ~PAGE_MASK) {
 190                         if (i > 0)
 191                                 goto out_unmap;
 192                         else
 193                                 ++frmr->dma_npages;
 194                 }
 195
 196                 if ((dma_addr + dma_len) & ~PAGE_MASK) {
 197                         if (i < ibmr->sg_dma_len - 1)
 198                                 goto out_unmap;
 199                         else
 200                                 ++frmr->dma_npages;
 201                 }
 202
 203                 len += dma_len;
 204         }
 205         frmr->dma_npages += len >> PAGE_SHIFT;
 206
 207         if (frmr->dma_npages > ibmr->pool->fmr_attr.max_pages) {
 208                 ret = -EMSGSIZE;
 209                 goto out_unmap;
 210         }
 211
 212         ret = rds_ib_post_reg_frmr(ibmr);
 213         if (ret)
 214                 goto out_unmap;
 215
 216         if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 217                 rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
 218         else
 219                 rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
 220
 221         return ret;
 222
 223 out_unmap:
 224         ib_dma_unmap_sg(rds_ibdev->dev, ibmr->sg, ibmr->sg_len,
 225                         DMA_BIDIRECTIONAL);
 226         ibmr->sg_dma_len = 0;
 227         return ret;
 228 }
 229
 230 static int rds_ib_post_inv(struct rds_ib_mr *ibmr)
 231 {
 232         struct ib_send_wr *s_wr, *failed_wr;
 233         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 234         struct rdma_cm_id *i_cm_id = ibmr->ic->i_cm_id;
 235         int ret = -EINVAL;
 236
 237         if (!i_cm_id || !i_cm_id->qp || !frmr->mr)
 238                 goto out;
 239
 240         if (frmr->fr_state != FRMR_IS_INUSE)
 241                 goto out;
 242
 243         while (atomic_dec_return(&ibmr->ic->i_fastreg_wrs) <= 0) {
 244                 atomic_inc(&ibmr->ic->i_fastreg_wrs);
 245                 cpu_relax();
 246         }
 247
 248         frmr->fr_inv = true;
 249         s_wr = &frmr->fr_wr;
 250
 251         memset(s_wr, 0, sizeof(*s_wr));
 252         s_wr->wr_id = (unsigned long)(void *)ibmr;
 253         s_wr->opcode = IB_WR_LOCAL_INV;
 254         s_wr->ex.invalidate_rkey = frmr->mr->rkey;
 255         s_wr->send_flags = IB_SEND_SIGNALED;
 256
 257         failed_wr = s_wr;
 258         ret = ib_post_send(i_cm_id->qp, s_wr, &failed_wr);
 259         WARN_ON(failed_wr != s_wr);
 260         if (unlikely(ret)) {
 261                 frmr->fr_state = FRMR_IS_STALE;
 262                 frmr->fr_inv = false;
 263                 atomic_inc(&ibmr->ic->i_fastreg_wrs);
 264                 pr_err("RDS/IB: %s returned error(%d)\n", __func__, ret);
 265                 goto out;
 266         }
 267 out:
 268         return ret;
 269 }
 270
 271 void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc)
 272 {
 273         struct rds_ib_mr *ibmr = (void *)(unsigned long)wc->wr_id;
 274         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 275
 276         if (wc->status != IB_WC_SUCCESS) {
 277                 frmr->fr_state = FRMR_IS_STALE;
 278                 if (rds_conn_up(ic->conn))
 279                         rds_ib_conn_error(ic->conn,
 280                                           "frmr completion <%pI4,%pI4> status %u(%s), vendor_err 0x%x, disconnecting and reconnecting\n",
 281                                           &ic->conn->c_laddr,
 282                                           &ic->conn->c_faddr,
 283                                           wc->status,
 284                                           ib_wc_status_msg(wc->status),
 285                                           wc->vendor_err);
 286         }
 287
 288         if (frmr->fr_inv) {
 289                 frmr->fr_state = FRMR_IS_FREE;
 290                 frmr->fr_inv = false;
 291         }
 292
 293         atomic_inc(&ic->i_fastreg_wrs);
 294 }
 295
 296 void rds_ib_unreg_frmr(struct list_head *list, unsigned int *nfreed,
 297                        unsigned long *unpinned, unsigned int goal)
 298 {
 299         struct rds_ib_mr *ibmr, *next;
 300         struct rds_ib_frmr *frmr;
 301         int ret = 0;
 302         unsigned int freed = *nfreed;
 303
 304         /* String all ib_mr's onto one list and hand them to ib_unmap_fmr */
 305         list_for_each_entry(ibmr, list, unmap_list) {
 306                 if (ibmr->sg_dma_len)
 307                         ret |= rds_ib_post_inv(ibmr);
 308         }
 309         if (ret)
 310                 pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, ret);
 311
 312         /* Now we can destroy the DMA mapping and unpin any pages */
 313         list_for_each_entry_safe(ibmr, next, list, unmap_list) {
 314                 *unpinned += ibmr->sg_len;
 315                 frmr = &ibmr->u.frmr;
 316                 __rds_ib_teardown_mr(ibmr);
 317                 if (freed < goal || frmr->fr_state == FRMR_IS_STALE) {
 318                         /* Don't de-allocate if the MR is not free yet */
 319                         if (frmr->fr_state == FRMR_IS_INUSE)
 320                                 continue;
 321
 322                         if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 323                                 rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
 324                         else
 325                                 rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
 326                         list_del(&ibmr->unmap_list);
 327                         if (frmr->mr)
 328                                 ib_dereg_mr(frmr->mr);
 329                         kfree(ibmr);
 330                         freed++;
 331                 }
 332         }
 333         *nfreed = freed;
 334 }
 335
 336 struct rds_ib_mr *rds_ib_reg_frmr(struct rds_ib_device *rds_ibdev,
 337                                   struct rds_ib_connection *ic,
 338                                   struct scatterlist *sg,
 339                                   unsigned long nents, u32 *key)
 340 {
 341         struct rds_ib_mr *ibmr = NULL;
 342         struct rds_ib_frmr *frmr;
 343         int ret;
 344
 345         do {
 346                 if (ibmr)
 347                         rds_ib_free_frmr(ibmr, true);
 348                 ibmr = rds_ib_alloc_frmr(rds_ibdev, nents);
 349                 if (IS_ERR(ibmr))
 350                         return ibmr;
 351                 frmr = &ibmr->u.frmr;
 352         } while (frmr->fr_state != FRMR_IS_FREE);
 353
 354         ibmr->ic = ic;
 355         ibmr->device = rds_ibdev;
 356         ret = rds_ib_map_frmr(rds_ibdev, ibmr->pool, ibmr, sg, nents);
 357         if (ret == 0) {
 358                 *key = frmr->mr->rkey;
 359         } else {
 360                 rds_ib_free_frmr(ibmr, false);
 361                 ibmr = ERR_PTR(ret);
 362         }
 363
 364         return ibmr;
 365 }
 366
 367 void rds_ib_free_frmr_list(struct rds_ib_mr *ibmr)
 368 {
 369         struct rds_ib_mr_pool *pool = ibmr->pool;
 370         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 371
 372         if (frmr->fr_state == FRMR_IS_STALE)
 373                 llist_add(&ibmr->llnode, &pool->drop_list);
 374         else
 375                 llist_add(&ibmr->llnode, &pool->free_list);
 376 }