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_reg_wr reg_wr;
 106         int ret, off = 0;
 107
 108         while (atomic_dec_return(&ibmr->ic->i_fastreg_wrs) <= 0) {
 109                 atomic_inc(&ibmr->ic->i_fastreg_wrs);
 110                 cpu_relax();
 111         }
 112
 113         ret = ib_map_mr_sg_zbva(frmr->mr, ibmr->sg, ibmr->sg_len,
 114                                 &off, 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         ret = ib_post_send(ibmr->ic->i_cm_id->qp, &reg_wr.wr, NULL);
 138         if (unlikely(ret)) {
 139                 /* Failure here can be because of -ENOMEM as well */
 140                 frmr->fr_state = FRMR_IS_STALE;
 141                 atomic_inc(&ibmr->ic->i_fastreg_wrs);
 142                 if (printk_ratelimit())
 143                         pr_warn("RDS/IB: %s returned error(%d)\n",
 144                                 __func__, ret);
 145         }
 146         return ret;
 147 }
 148
 149 static int rds_ib_map_frmr(struct rds_ib_device *rds_ibdev,
 150                            struct rds_ib_mr_pool *pool,
 151                            struct rds_ib_mr *ibmr,
 152                            struct scatterlist *sg, unsigned int sg_len)
 153 {
 154         struct ib_device *dev = rds_ibdev->dev;
 155         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 156         int i;
 157         u32 len;
 158         int ret = 0;
 159
 160         /* We want to teardown old ibmr values here and fill it up with
 161          * new sg values
 162          */
 163         rds_ib_teardown_mr(ibmr);
 164
 165         ibmr->sg = sg;
 166         ibmr->sg_len = sg_len;
 167         ibmr->sg_dma_len = 0;
 168         frmr->sg_byte_len = 0;
 169         WARN_ON(ibmr->sg_dma_len);
 170         ibmr->sg_dma_len = ib_dma_map_sg(dev, ibmr->sg, ibmr->sg_len,
 171                                          DMA_BIDIRECTIONAL);
 172         if (unlikely(!ibmr->sg_dma_len)) {
 173                 pr_warn("RDS/IB: %s failed!\n", __func__);
 174                 return -EBUSY;
 175         }
 176
 177         frmr->sg_byte_len = 0;
 178         frmr->dma_npages = 0;
 179         len = 0;
 180
 181         ret = -EINVAL;
 182         for (i = 0; i < ibmr->sg_dma_len; ++i) {
 183                 unsigned int dma_len = ib_sg_dma_len(dev, &ibmr->sg[i]);
 184                 u64 dma_addr = ib_sg_dma_address(dev, &ibmr->sg[i]);
 185
 186                 frmr->sg_byte_len += dma_len;
 187                 if (dma_addr & ~PAGE_MASK) {
 188                         if (i > 0)
 189                                 goto out_unmap;
 190                         else
 191                                 ++frmr->dma_npages;
 192                 }
 193
 194                 if ((dma_addr + dma_len) & ~PAGE_MASK) {
 195                         if (i < ibmr->sg_dma_len - 1)
 196                                 goto out_unmap;
 197                         else
 198                                 ++frmr->dma_npages;
 199                 }
 200
 201                 len += dma_len;
 202         }
 203         frmr->dma_npages += len >> PAGE_SHIFT;
 204
 205         if (frmr->dma_npages > ibmr->pool->fmr_attr.max_pages) {
 206                 ret = -EMSGSIZE;
 207                 goto out_unmap;
 208         }
 209
 210         ret = rds_ib_post_reg_frmr(ibmr);
 211         if (ret)
 212                 goto out_unmap;
 213
 214         if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 215                 rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
 216         else
 217                 rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
 218
 219         return ret;
 220
 221 out_unmap:
 222         ib_dma_unmap_sg(rds_ibdev->dev, ibmr->sg, ibmr->sg_len,
 223                         DMA_BIDIRECTIONAL);
 224         ibmr->sg_dma_len = 0;
 225         return ret;
 226 }
 227
 228 static int rds_ib_post_inv(struct rds_ib_mr *ibmr)
 229 {
 230         struct ib_send_wr *s_wr;
 231         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 232         struct rdma_cm_id *i_cm_id = ibmr->ic->i_cm_id;
 233         int ret = -EINVAL;
 234
 235         if (!i_cm_id || !i_cm_id->qp || !frmr->mr)
 236                 goto out;
 237
 238         if (frmr->fr_state != FRMR_IS_INUSE)
 239                 goto out;
 240
 241         while (atomic_dec_return(&ibmr->ic->i_fastunreg_wrs) <= 0) {
 242                 atomic_inc(&ibmr->ic->i_fastunreg_wrs);
 243                 cpu_relax();
 244         }
 245
 246         frmr->fr_inv = true;
 247         s_wr = &frmr->fr_wr;
 248
 249         memset(s_wr, 0, sizeof(*s_wr));
 250         s_wr->wr_id = (unsigned long)(void *)ibmr;
 251         s_wr->opcode = IB_WR_LOCAL_INV;
 252         s_wr->ex.invalidate_rkey = frmr->mr->rkey;
 253         s_wr->send_flags = IB_SEND_SIGNALED;
 254
 255         ret = ib_post_send(i_cm_id->qp, s_wr, NULL);
 256         if (unlikely(ret)) {
 257                 frmr->fr_state = FRMR_IS_STALE;
 258                 frmr->fr_inv = false;
 259                 atomic_inc(&ibmr->ic->i_fastunreg_wrs);
 260                 pr_err("RDS/IB: %s returned error(%d)\n", __func__, ret);
 261                 goto out;
 262         }
 263 out:
 264         return ret;
 265 }
 266
 267 void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc)
 268 {
 269         struct rds_ib_mr *ibmr = (void *)(unsigned long)wc->wr_id;
 270         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 271
 272         if (wc->status != IB_WC_SUCCESS) {
 273                 frmr->fr_state = FRMR_IS_STALE;
 274                 if (rds_conn_up(ic->conn))
 275                         rds_ib_conn_error(ic->conn,
 276                                           "frmr completion <%pI4,%pI4> status %u(%s), vendor_err 0x%x, disconnecting and reconnecting\n",
 277                                           &ic->conn->c_laddr,
 278                                           &ic->conn->c_faddr,
 279                                           wc->status,
 280                                           ib_wc_status_msg(wc->status),
 281                                           wc->vendor_err);
 282         }
 283
 284         if (frmr->fr_inv) {
 285                 frmr->fr_state = FRMR_IS_FREE;
 286                 frmr->fr_inv = false;
 287                 atomic_inc(&ic->i_fastreg_wrs);
 288         } else {
 289                 atomic_inc(&ic->i_fastunreg_wrs);
 290         }
 291 }
 292
 293 void rds_ib_unreg_frmr(struct list_head *list, unsigned int *nfreed,
 294                        unsigned long *unpinned, unsigned int goal)
 295 {
 296         struct rds_ib_mr *ibmr, *next;
 297         struct rds_ib_frmr *frmr;
 298         int ret = 0;
 299         unsigned int freed = *nfreed;
 300
 301         /* String all ib_mr's onto one list and hand them to ib_unmap_fmr */
 302         list_for_each_entry(ibmr, list, unmap_list) {
 303                 if (ibmr->sg_dma_len)
 304                         ret |= rds_ib_post_inv(ibmr);
 305         }
 306         if (ret)
 307                 pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, ret);
 308
 309         /* Now we can destroy the DMA mapping and unpin any pages */
 310         list_for_each_entry_safe(ibmr, next, list, unmap_list) {
 311                 *unpinned += ibmr->sg_len;
 312                 frmr = &ibmr->u.frmr;
 313                 __rds_ib_teardown_mr(ibmr);
 314                 if (freed < goal || frmr->fr_state == FRMR_IS_STALE) {
 315                         /* Don't de-allocate if the MR is not free yet */
 316                         if (frmr->fr_state == FRMR_IS_INUSE)
 317                                 continue;
 318
 319                         if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 320                                 rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
 321                         else
 322                                 rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
 323                         list_del(&ibmr->unmap_list);
 324                         if (frmr->mr)
 325                                 ib_dereg_mr(frmr->mr);
 326                         kfree(ibmr);
 327                         freed++;
 328                 }
 329         }
 330         *nfreed = freed;
 331 }
 332
 333 struct rds_ib_mr *rds_ib_reg_frmr(struct rds_ib_device *rds_ibdev,
 334                                   struct rds_ib_connection *ic,
 335                                   struct scatterlist *sg,
 336                                   unsigned long nents, u32 *key)
 337 {
 338         struct rds_ib_mr *ibmr = NULL;
 339         struct rds_ib_frmr *frmr;
 340         int ret;
 341
 342         if (!ic) {
 343                 /* TODO: Add FRWR support for RDS_GET_MR using proxy qp*/
 344                 return ERR_PTR(-EOPNOTSUPP);
 345         }
 346
 347         do {
 348                 if (ibmr)
 349                         rds_ib_free_frmr(ibmr, true);
 350                 ibmr = rds_ib_alloc_frmr(rds_ibdev, nents);
 351                 if (IS_ERR(ibmr))
 352                         return ibmr;
 353                 frmr = &ibmr->u.frmr;
 354         } while (frmr->fr_state != FRMR_IS_FREE);
 355
 356         ibmr->ic = ic;
 357         ibmr->device = rds_ibdev;
 358         ret = rds_ib_map_frmr(rds_ibdev, ibmr->pool, ibmr, sg, nents);
 359         if (ret == 0) {
 360                 *key = frmr->mr->rkey;
 361         } else {
 362                 rds_ib_free_frmr(ibmr, false);
 363                 ibmr = ERR_PTR(ret);
 364         }
 365
 366         return ibmr;
 367 }
 368
 369 void rds_ib_free_frmr_list(struct rds_ib_mr *ibmr)
 370 {
 371         struct rds_ib_mr_pool *pool = ibmr->pool;
 372         struct rds_ib_frmr *frmr = &ibmr->u.frmr;
 373
 374         if (frmr->fr_state == FRMR_IS_STALE)
 375                 llist_add(&ibmr->llnode, &pool->drop_list);
 376         else
 377                 llist_add(&ibmr->llnode, &pool->free_list);
 378 }