drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c

   1 /*
   2  * Copyright (c) 2012-2016 VMware, Inc.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of EITHER the GNU General Public License
   6  * version 2 as published by the Free Software Foundation or the BSD
   7  * 2-Clause License. This program is distributed in the hope that it
   8  * will be useful, but WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED
   9  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
  10  * See the GNU General Public License version 2 for more details at
  11  * http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program available in the file COPYING in the main
  15  * directory of this source tree.
  16  *
  17  * The BSD 2-Clause License
  18  *
  19  *     Redistribution and use in source and binary forms, with or
  20  *     without modification, are permitted provided that the following
  21  *     conditions are met:
  22  *
  23  *      - Redistributions of source code must retain the above
  24  *        copyright notice, this list of conditions and the following
  25  *        disclaimer.
  26  *
  27  *      - Redistributions in binary form must reproduce the above
  28  *        copyright notice, this list of conditions and the following
  29  *        disclaimer in the documentation and/or other materials
  30  *        provided with the distribution.
  31  *
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  35  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  36  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  37  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  38  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  39  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  41  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  42  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  43  * OF THE POSSIBILITY OF SUCH DAMAGE.
  44  */
  45
  46 #include <asm/page.h>
  47 #include <linux/io.h>
  48 #include <linux/wait.h>
  49 #include <rdma/ib_addr.h>
  50 #include <rdma/ib_smi.h>
  51 #include <rdma/ib_user_verbs.h>
  52 #include <rdma/uverbs_ioctl.h>
  53
  54 #include "pvrdma.h"
  55
  56 /**
  57  * pvrdma_req_notify_cq - request notification for a completion queue
  58  * @ibcq: the completion queue
  59  * @notify_flags: notification flags
  60  *
  61  * @return: 0 for success.
  62  */
  63 int pvrdma_req_notify_cq(struct ib_cq *ibcq,
  64                          enum ib_cq_notify_flags notify_flags)
  65 {
  66         struct pvrdma_dev *dev = to_vdev(ibcq->device);
  67         struct pvrdma_cq *cq = to_vcq(ibcq);
  68         u32 val = cq->cq_handle;
  69         unsigned long flags;
  70         int has_data = 0;
  71
  72         val |= (notify_flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED ?
  73                 PVRDMA_UAR_CQ_ARM_SOL : PVRDMA_UAR_CQ_ARM;
  74
  75         spin_lock_irqsave(&cq->cq_lock, flags);
  76
  77         pvrdma_write_uar_cq(dev, val);
  78
  79         if (notify_flags & IB_CQ_REPORT_MISSED_EVENTS) {
  80                 unsigned int head;
  81
  82                 has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
  83                                                     cq->ibcq.cqe, &head);
  84                 if (unlikely(has_data == PVRDMA_INVALID_IDX))
  85                         dev_err(&dev->pdev->dev, "CQ ring state invalid\n");
  86         }
  87
  88         spin_unlock_irqrestore(&cq->cq_lock, flags);
  89
  90         return has_data;
  91 }
  92
  93 /**
  94  * pvrdma_create_cq - create completion queue
  95  * @ibcq: Allocated CQ
  96  * @attr: completion queue attributes
  97  * @udata: user data
  98  *
  99  * @return: 0 on success
 100  */
 101 int pvrdma_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 102                      struct ib_udata *udata)
 103 {
 104         struct ib_device *ibdev = ibcq->device;
 105         int entries = attr->cqe;
 106         struct pvrdma_dev *dev = to_vdev(ibdev);
 107         struct pvrdma_cq *cq = to_vcq(ibcq);
 108         int ret;
 109         int npages;
 110         unsigned long flags;
 111         union pvrdma_cmd_req req;
 112         union pvrdma_cmd_resp rsp;
 113         struct pvrdma_cmd_create_cq *cmd = &req.create_cq;
 114         struct pvrdma_cmd_create_cq_resp *resp = &rsp.create_cq_resp;
 115         struct pvrdma_create_cq_resp cq_resp = {};
 116         struct pvrdma_create_cq ucmd;
 117         struct pvrdma_ucontext *context = rdma_udata_to_drv_context(
 118                 udata, struct pvrdma_ucontext, ibucontext);
 119
 120         BUILD_BUG_ON(sizeof(struct pvrdma_cqe) != 64);
 121
 122         entries = roundup_pow_of_two(entries);
 123         if (entries < 1 || entries > dev->dsr->caps.max_cqe)
 124                 return -EINVAL;
 125
 126         if (!atomic_add_unless(&dev->num_cqs, 1, dev->dsr->caps.max_cq))
 127                 return -ENOMEM;
 128
 129         cq->ibcq.cqe = entries;
 130         cq->is_kernel = !udata;
 131
 132         if (!cq->is_kernel) {
 133                 if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd))) {
 134                         ret = -EFAULT;
 135                         goto err_cq;
 136                 }
 137
 138                 cq->umem = ib_umem_get(ibdev, ucmd.buf_addr, ucmd.buf_size,
 139                                        IB_ACCESS_LOCAL_WRITE);
 140                 if (IS_ERR(cq->umem)) {
 141                         ret = PTR_ERR(cq->umem);
 142                         goto err_cq;
 143                 }
 144
 145                 npages = ib_umem_page_count(cq->umem);
 146         } else {
 147                 /* One extra page for shared ring state */
 148                 npages = 1 + (entries * sizeof(struct pvrdma_cqe) +
 149                               PAGE_SIZE - 1) / PAGE_SIZE;
 150
 151                 /* Skip header page. */
 152                 cq->offset = PAGE_SIZE;
 153         }
 154
 155         if (npages < 0 || npages > PVRDMA_PAGE_DIR_MAX_PAGES) {
 156                 dev_warn(&dev->pdev->dev,
 157                          "overflow pages in completion queue\n");
 158                 ret = -EINVAL;
 159                 goto err_umem;
 160         }
 161
 162         ret = pvrdma_page_dir_init(dev, &cq->pdir, npages, cq->is_kernel);
 163         if (ret) {
 164                 dev_warn(&dev->pdev->dev,
 165                          "could not allocate page directory\n");
 166                 goto err_umem;
 167         }
 168
 169         /* Ring state is always the first page. Set in library for user cq. */
 170         if (cq->is_kernel)
 171                 cq->ring_state = cq->pdir.pages[0];
 172         else
 173                 pvrdma_page_dir_insert_umem(&cq->pdir, cq->umem, 0);
 174
 175         refcount_set(&cq->refcnt, 1);
 176         init_completion(&cq->free);
 177         spin_lock_init(&cq->cq_lock);
 178
 179         memset(cmd, 0, sizeof(*cmd));
 180         cmd->hdr.cmd = PVRDMA_CMD_CREATE_CQ;
 181         cmd->nchunks = npages;
 182         cmd->ctx_handle = context ? context->ctx_handle : 0;
 183         cmd->cqe = entries;
 184         cmd->pdir_dma = cq->pdir.dir_dma;
 185         ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_CQ_RESP);
 186         if (ret < 0) {
 187                 dev_warn(&dev->pdev->dev,
 188                          "could not create completion queue, error: %d\n", ret);
 189                 goto err_page_dir;
 190         }
 191
 192         cq->ibcq.cqe = resp->cqe;
 193         cq->cq_handle = resp->cq_handle;
 194         cq_resp.cqn = resp->cq_handle;
 195         spin_lock_irqsave(&dev->cq_tbl_lock, flags);
 196         dev->cq_tbl[cq->cq_handle % dev->dsr->caps.max_cq] = cq;
 197         spin_unlock_irqrestore(&dev->cq_tbl_lock, flags);
 198
 199         if (!cq->is_kernel) {
 200                 cq->uar = &context->uar;
 201
 202                 /* Copy udata back. */
 203                 if (ib_copy_to_udata(udata, &cq_resp, sizeof(cq_resp))) {
 204                         dev_warn(&dev->pdev->dev,
 205                                  "failed to copy back udata\n");
 206                         pvrdma_destroy_cq(&cq->ibcq, udata);
 207                         return -EINVAL;
 208                 }
 209         }
 210
 211         return 0;
 212
 213 err_page_dir:
 214         pvrdma_page_dir_cleanup(dev, &cq->pdir);
 215 err_umem:
 216         ib_umem_release(cq->umem);
 217 err_cq:
 218         atomic_dec(&dev->num_cqs);
 219         return ret;
 220 }
 221
 222 static void pvrdma_free_cq(struct pvrdma_dev *dev, struct pvrdma_cq *cq)
 223 {
 224         if (refcount_dec_and_test(&cq->refcnt))
 225                 complete(&cq->free);
 226         wait_for_completion(&cq->free);
 227
 228         ib_umem_release(cq->umem);
 229
 230         pvrdma_page_dir_cleanup(dev, &cq->pdir);
 231 }
 232
 233 /**
 234  * pvrdma_destroy_cq - destroy completion queue
 235  * @cq: the completion queue to destroy.
 236  * @udata: user data or null for kernel object
 237  */
 238 void pvrdma_destroy_cq(struct ib_cq *cq, struct ib_udata *udata)
 239 {
 240         struct pvrdma_cq *vcq = to_vcq(cq);
 241         union pvrdma_cmd_req req;
 242         struct pvrdma_cmd_destroy_cq *cmd = &req.destroy_cq;
 243         struct pvrdma_dev *dev = to_vdev(cq->device);
 244         unsigned long flags;
 245         int ret;
 246
 247         memset(cmd, 0, sizeof(*cmd));
 248         cmd->hdr.cmd = PVRDMA_CMD_DESTROY_CQ;
 249         cmd->cq_handle = vcq->cq_handle;
 250
 251         ret = pvrdma_cmd_post(dev, &req, NULL, 0);
 252         if (ret < 0)
 253                 dev_warn(&dev->pdev->dev,
 254                          "could not destroy completion queue, error: %d\n",
 255                          ret);
 256
 257         /* free cq's resources */
 258         spin_lock_irqsave(&dev->cq_tbl_lock, flags);
 259         dev->cq_tbl[vcq->cq_handle] = NULL;
 260         spin_unlock_irqrestore(&dev->cq_tbl_lock, flags);
 261
 262         pvrdma_free_cq(dev, vcq);
 263         atomic_dec(&dev->num_cqs);
 264 }
 265
 266 static inline struct pvrdma_cqe *get_cqe(struct pvrdma_cq *cq, int i)
 267 {
 268         return (struct pvrdma_cqe *)pvrdma_page_dir_get_ptr(
 269                                         &cq->pdir,
 270                                         cq->offset +
 271                                         sizeof(struct pvrdma_cqe) * i);
 272 }
 273
 274 void _pvrdma_flush_cqe(struct pvrdma_qp *qp, struct pvrdma_cq *cq)
 275 {
 276         unsigned int head;
 277         int has_data;
 278
 279         if (!cq->is_kernel)
 280                 return;
 281
 282         /* Lock held */
 283         has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
 284                                             cq->ibcq.cqe, &head);
 285         if (unlikely(has_data > 0)) {
 286                 int items;
 287                 int curr;
 288                 int tail = pvrdma_idx(&cq->ring_state->rx.prod_tail,
 289                                       cq->ibcq.cqe);
 290                 struct pvrdma_cqe *cqe;
 291                 struct pvrdma_cqe *curr_cqe;
 292
 293                 items = (tail > head) ? (tail - head) :
 294                         (cq->ibcq.cqe - head + tail);
 295                 curr = --tail;
 296                 while (items-- > 0) {
 297                         if (curr < 0)
 298                                 curr = cq->ibcq.cqe - 1;
 299                         if (tail < 0)
 300                                 tail = cq->ibcq.cqe - 1;
 301                         curr_cqe = get_cqe(cq, curr);
 302                         if ((curr_cqe->qp & 0xFFFF) != qp->qp_handle) {
 303                                 if (curr != tail) {
 304                                         cqe = get_cqe(cq, tail);
 305                                         *cqe = *curr_cqe;
 306                                 }
 307                                 tail--;
 308                         } else {
 309                                 pvrdma_idx_ring_inc(
 310                                         &cq->ring_state->rx.cons_head,
 311                                         cq->ibcq.cqe);
 312                         }
 313                         curr--;
 314                 }
 315         }
 316 }
 317
 318 static int pvrdma_poll_one(struct pvrdma_cq *cq, struct pvrdma_qp **cur_qp,
 319                            struct ib_wc *wc)
 320 {
 321         struct pvrdma_dev *dev = to_vdev(cq->ibcq.device);
 322         int has_data;
 323         unsigned int head;
 324         bool tried = false;
 325         struct pvrdma_cqe *cqe;
 326
 327 retry:
 328         has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
 329                                             cq->ibcq.cqe, &head);
 330         if (has_data == 0) {
 331                 if (tried)
 332                         return -EAGAIN;
 333
 334                 pvrdma_write_uar_cq(dev, cq->cq_handle | PVRDMA_UAR_CQ_POLL);
 335
 336                 tried = true;
 337                 goto retry;
 338         } else if (has_data == PVRDMA_INVALID_IDX) {
 339                 dev_err(&dev->pdev->dev, "CQ ring state invalid\n");
 340                 return -EAGAIN;
 341         }
 342
 343         cqe = get_cqe(cq, head);
 344
 345         /* Ensure cqe is valid. */
 346         rmb();
 347         if (dev->qp_tbl[cqe->qp & 0xffff])
 348                 *cur_qp = (struct pvrdma_qp *)dev->qp_tbl[cqe->qp & 0xffff];
 349         else
 350                 return -EAGAIN;
 351
 352         wc->opcode = pvrdma_wc_opcode_to_ib(cqe->opcode);
 353         wc->status = pvrdma_wc_status_to_ib(cqe->status);
 354         wc->wr_id = cqe->wr_id;
 355         wc->qp = &(*cur_qp)->ibqp;
 356         wc->byte_len = cqe->byte_len;
 357         wc->ex.imm_data = cqe->imm_data;
 358         wc->src_qp = cqe->src_qp;
 359         wc->wc_flags = pvrdma_wc_flags_to_ib(cqe->wc_flags);
 360         wc->pkey_index = cqe->pkey_index;
 361         wc->slid = cqe->slid;
 362         wc->sl = cqe->sl;
 363         wc->dlid_path_bits = cqe->dlid_path_bits;
 364         wc->port_num = cqe->port_num;
 365         wc->vendor_err = cqe->vendor_err;
 366         wc->network_hdr_type = cqe->network_hdr_type;
 367
 368         /* Update shared ring state */
 369         pvrdma_idx_ring_inc(&cq->ring_state->rx.cons_head, cq->ibcq.cqe);
 370
 371         return 0;
 372 }
 373
 374 /**
 375  * pvrdma_poll_cq - poll for work completion queue entries
 376  * @ibcq: completion queue
 377  * @num_entries: the maximum number of entries
 378  * @entry: pointer to work completion array
 379  *
 380  * @return: number of polled completion entries
 381  */
 382 int pvrdma_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc)
 383 {
 384         struct pvrdma_cq *cq = to_vcq(ibcq);
 385         struct pvrdma_qp *cur_qp = NULL;
 386         unsigned long flags;
 387         int npolled;
 388
 389         if (num_entries < 1 || wc == NULL)
 390                 return 0;
 391
 392         spin_lock_irqsave(&cq->cq_lock, flags);
 393         for (npolled = 0; npolled < num_entries; ++npolled) {
 394                 if (pvrdma_poll_one(cq, &cur_qp, wc + npolled))
 395                         break;
 396         }
 397
 398         spin_unlock_irqrestore(&cq->cq_lock, flags);
 399
 400         /* Ensure we do not return errors from poll_cq */
 401         return npolled;
 402 }