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
  53 #include "pvrdma.h"
  54
  55 /**
  56  * pvrdma_req_notify_cq - request notification for a completion queue
  57  * @ibcq: the completion queue
  58  * @notify_flags: notification flags
  59  *
  60  * @return: 0 for success.
  61  */
  62 int pvrdma_req_notify_cq(struct ib_cq *ibcq,
  63                          enum ib_cq_notify_flags notify_flags)
  64 {
  65         struct pvrdma_dev *dev = to_vdev(ibcq->device);
  66         struct pvrdma_cq *cq = to_vcq(ibcq);
  67         u32 val = cq->cq_handle;
  68         unsigned long flags;
  69         int has_data = 0;
  70
  71         val |= (notify_flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED ?
  72                 PVRDMA_UAR_CQ_ARM_SOL : PVRDMA_UAR_CQ_ARM;
  73
  74         spin_lock_irqsave(&cq->cq_lock, flags);
  75
  76         pvrdma_write_uar_cq(dev, val);
  77
  78         if (notify_flags & IB_CQ_REPORT_MISSED_EVENTS) {
  79                 unsigned int head;
  80
  81                 has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
  82                                                     cq->ibcq.cqe, &head);
  83                 if (unlikely(has_data == PVRDMA_INVALID_IDX))
  84                         dev_err(&dev->pdev->dev, "CQ ring state invalid\n");
  85         }
  86
  87         spin_unlock_irqrestore(&cq->cq_lock, flags);
  88
  89         return has_data;
  90 }
  91
  92 /**
  93  * pvrdma_create_cq - create completion queue
  94  * @ibdev: the device
  95  * @attr: completion queue attributes
  96  * @context: user context
  97  * @udata: user data
  98  *
  99  * @return: ib_cq completion queue pointer on success,
 100  *          otherwise returns negative errno.
 101  */
 102 struct ib_cq *pvrdma_create_cq(struct ib_device *ibdev,
 103                                const struct ib_cq_init_attr *attr,
 104                                struct ib_ucontext *context,
 105                                struct ib_udata *udata)
 106 {
 107         int entries = attr->cqe;
 108         struct pvrdma_dev *dev = to_vdev(ibdev);
 109         struct pvrdma_cq *cq;
 110         int ret;
 111         int npages;
 112         unsigned long flags;
 113         union pvrdma_cmd_req req;
 114         union pvrdma_cmd_resp rsp;
 115         struct pvrdma_cmd_create_cq *cmd = &req.create_cq;
 116         struct pvrdma_cmd_create_cq_resp *resp = &rsp.create_cq_resp;
 117         struct pvrdma_create_cq_resp cq_resp = {0};
 118         struct pvrdma_create_cq ucmd;
 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 ERR_PTR(-EINVAL);
 125
 126         if (!atomic_add_unless(&dev->num_cqs, 1, dev->dsr->caps.max_cq))
 127                 return ERR_PTR(-ENOMEM);
 128
 129         cq = kzalloc(sizeof(*cq), GFP_KERNEL);
 130         if (!cq) {
 131                 atomic_dec(&dev->num_cqs);
 132                 return ERR_PTR(-ENOMEM);
 133         }
 134
 135         cq->ibcq.cqe = entries;
 136         cq->is_kernel = !context;
 137
 138         if (!cq->is_kernel) {
 139                 if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd))) {
 140                         ret = -EFAULT;
 141                         goto err_cq;
 142                 }
 143
 144                 cq->umem = ib_umem_get(context, ucmd.buf_addr, ucmd.buf_size,
 145                                        IB_ACCESS_LOCAL_WRITE, 1);
 146                 if (IS_ERR(cq->umem)) {
 147                         ret = PTR_ERR(cq->umem);
 148                         goto err_cq;
 149                 }
 150
 151                 npages = ib_umem_page_count(cq->umem);
 152         } else {
 153                 /* One extra page for shared ring state */
 154                 npages = 1 + (entries * sizeof(struct pvrdma_cqe) +
 155                               PAGE_SIZE - 1) / PAGE_SIZE;
 156
 157                 /* Skip header page. */
 158                 cq->offset = PAGE_SIZE;
 159         }
 160
 161         if (npages < 0 || npages > PVRDMA_PAGE_DIR_MAX_PAGES) {
 162                 dev_warn(&dev->pdev->dev,
 163                          "overflow pages in completion queue\n");
 164                 ret = -EINVAL;
 165                 goto err_umem;
 166         }
 167
 168         ret = pvrdma_page_dir_init(dev, &cq->pdir, npages, cq->is_kernel);
 169         if (ret) {
 170                 dev_warn(&dev->pdev->dev,
 171                          "could not allocate page directory\n");
 172                 goto err_umem;
 173         }
 174
 175         /* Ring state is always the first page. Set in library for user cq. */
 176         if (cq->is_kernel)
 177                 cq->ring_state = cq->pdir.pages[0];
 178         else
 179                 pvrdma_page_dir_insert_umem(&cq->pdir, cq->umem, 0);
 180
 181         refcount_set(&cq->refcnt, 1);
 182         init_completion(&cq->free);
 183         spin_lock_init(&cq->cq_lock);
 184
 185         memset(cmd, 0, sizeof(*cmd));
 186         cmd->hdr.cmd = PVRDMA_CMD_CREATE_CQ;
 187         cmd->nchunks = npages;
 188         cmd->ctx_handle = (context) ?
 189                 (u64)to_vucontext(context)->ctx_handle : 0;
 190         cmd->cqe = entries;
 191         cmd->pdir_dma = cq->pdir.dir_dma;
 192         ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_CQ_RESP);
 193         if (ret < 0) {
 194                 dev_warn(&dev->pdev->dev,
 195                          "could not create completion queue, error: %d\n", ret);
 196                 goto err_page_dir;
 197         }
 198
 199         cq->ibcq.cqe = resp->cqe;
 200         cq->cq_handle = resp->cq_handle;
 201         cq_resp.cqn = resp->cq_handle;
 202         spin_lock_irqsave(&dev->cq_tbl_lock, flags);
 203         dev->cq_tbl[cq->cq_handle % dev->dsr->caps.max_cq] = cq;
 204         spin_unlock_irqrestore(&dev->cq_tbl_lock, flags);
 205
 206         if (!cq->is_kernel) {
 207                 cq->uar = &(to_vucontext(context)->uar);
 208
 209                 /* Copy udata back. */
 210                 if (ib_copy_to_udata(udata, &cq_resp, sizeof(cq_resp))) {
 211                         dev_warn(&dev->pdev->dev,
 212                                  "failed to copy back udata\n");
 213                         pvrdma_destroy_cq(&cq->ibcq);
 214                         return ERR_PTR(-EINVAL);
 215                 }
 216         }
 217
 218         return &cq->ibcq;
 219
 220 err_page_dir:
 221         pvrdma_page_dir_cleanup(dev, &cq->pdir);
 222 err_umem:
 223         if (!cq->is_kernel)
 224                 ib_umem_release(cq->umem);
 225 err_cq:
 226         atomic_dec(&dev->num_cqs);
 227         kfree(cq);
 228
 229         return ERR_PTR(ret);
 230 }
 231
 232 static void pvrdma_free_cq(struct pvrdma_dev *dev, struct pvrdma_cq *cq)
 233 {
 234         if (refcount_dec_and_test(&cq->refcnt))
 235                 complete(&cq->free);
 236         wait_for_completion(&cq->free);
 237
 238         if (!cq->is_kernel)
 239                 ib_umem_release(cq->umem);
 240
 241         pvrdma_page_dir_cleanup(dev, &cq->pdir);
 242         kfree(cq);
 243 }
 244
 245 /**
 246  * pvrdma_destroy_cq - destroy completion queue
 247  * @cq: the completion queue to destroy.
 248  *
 249  * @return: 0 for success.
 250  */
 251 int pvrdma_destroy_cq(struct ib_cq *cq)
 252 {
 253         struct pvrdma_cq *vcq = to_vcq(cq);
 254         union pvrdma_cmd_req req;
 255         struct pvrdma_cmd_destroy_cq *cmd = &req.destroy_cq;
 256         struct pvrdma_dev *dev = to_vdev(cq->device);
 257         unsigned long flags;
 258         int ret;
 259
 260         memset(cmd, 0, sizeof(*cmd));
 261         cmd->hdr.cmd = PVRDMA_CMD_DESTROY_CQ;
 262         cmd->cq_handle = vcq->cq_handle;
 263
 264         ret = pvrdma_cmd_post(dev, &req, NULL, 0);
 265         if (ret < 0)
 266                 dev_warn(&dev->pdev->dev,
 267                          "could not destroy completion queue, error: %d\n",
 268                          ret);
 269
 270         /* free cq's resources */
 271         spin_lock_irqsave(&dev->cq_tbl_lock, flags);
 272         dev->cq_tbl[vcq->cq_handle] = NULL;
 273         spin_unlock_irqrestore(&dev->cq_tbl_lock, flags);
 274
 275         pvrdma_free_cq(dev, vcq);
 276         atomic_dec(&dev->num_cqs);
 277
 278         return ret;
 279 }
 280
 281 static inline struct pvrdma_cqe *get_cqe(struct pvrdma_cq *cq, int i)
 282 {
 283         return (struct pvrdma_cqe *)pvrdma_page_dir_get_ptr(
 284                                         &cq->pdir,
 285                                         cq->offset +
 286                                         sizeof(struct pvrdma_cqe) * i);
 287 }
 288
 289 void _pvrdma_flush_cqe(struct pvrdma_qp *qp, struct pvrdma_cq *cq)
 290 {
 291         unsigned int head;
 292         int has_data;
 293
 294         if (!cq->is_kernel)
 295                 return;
 296
 297         /* Lock held */
 298         has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
 299                                             cq->ibcq.cqe, &head);
 300         if (unlikely(has_data > 0)) {
 301                 int items;
 302                 int curr;
 303                 int tail = pvrdma_idx(&cq->ring_state->rx.prod_tail,
 304                                       cq->ibcq.cqe);
 305                 struct pvrdma_cqe *cqe;
 306                 struct pvrdma_cqe *curr_cqe;
 307
 308                 items = (tail > head) ? (tail - head) :
 309                         (cq->ibcq.cqe - head + tail);
 310                 curr = --tail;
 311                 while (items-- > 0) {
 312                         if (curr < 0)
 313                                 curr = cq->ibcq.cqe - 1;
 314                         if (tail < 0)
 315                                 tail = cq->ibcq.cqe - 1;
 316                         curr_cqe = get_cqe(cq, curr);
 317                         if ((curr_cqe->qp & 0xFFFF) != qp->qp_handle) {
 318                                 if (curr != tail) {
 319                                         cqe = get_cqe(cq, tail);
 320                                         *cqe = *curr_cqe;
 321                                 }
 322                                 tail--;
 323                         } else {
 324                                 pvrdma_idx_ring_inc(
 325                                         &cq->ring_state->rx.cons_head,
 326                                         cq->ibcq.cqe);
 327                         }
 328                         curr--;
 329                 }
 330         }
 331 }
 332
 333 static int pvrdma_poll_one(struct pvrdma_cq *cq, struct pvrdma_qp **cur_qp,
 334                            struct ib_wc *wc)
 335 {
 336         struct pvrdma_dev *dev = to_vdev(cq->ibcq.device);
 337         int has_data;
 338         unsigned int head;
 339         bool tried = false;
 340         struct pvrdma_cqe *cqe;
 341
 342 retry:
 343         has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
 344                                             cq->ibcq.cqe, &head);
 345         if (has_data == 0) {
 346                 if (tried)
 347                         return -EAGAIN;
 348
 349                 pvrdma_write_uar_cq(dev, cq->cq_handle | PVRDMA_UAR_CQ_POLL);
 350
 351                 tried = true;
 352                 goto retry;
 353         } else if (has_data == PVRDMA_INVALID_IDX) {
 354                 dev_err(&dev->pdev->dev, "CQ ring state invalid\n");
 355                 return -EAGAIN;
 356         }
 357
 358         cqe = get_cqe(cq, head);
 359
 360         /* Ensure cqe is valid. */
 361         rmb();
 362         if (dev->qp_tbl[cqe->qp & 0xffff])
 363                 *cur_qp = (struct pvrdma_qp *)dev->qp_tbl[cqe->qp & 0xffff];
 364         else
 365                 return -EAGAIN;
 366
 367         wc->opcode = pvrdma_wc_opcode_to_ib(cqe->opcode);
 368         wc->status = pvrdma_wc_status_to_ib(cqe->status);
 369         wc->wr_id = cqe->wr_id;
 370         wc->qp = &(*cur_qp)->ibqp;
 371         wc->byte_len = cqe->byte_len;
 372         wc->ex.imm_data = cqe->imm_data;
 373         wc->src_qp = cqe->src_qp;
 374         wc->wc_flags = pvrdma_wc_flags_to_ib(cqe->wc_flags);
 375         wc->pkey_index = cqe->pkey_index;
 376         wc->slid = cqe->slid;
 377         wc->sl = cqe->sl;
 378         wc->dlid_path_bits = cqe->dlid_path_bits;
 379         wc->port_num = cqe->port_num;
 380         wc->vendor_err = cqe->vendor_err;
 381         wc->network_hdr_type = cqe->network_hdr_type;
 382
 383         /* Update shared ring state */
 384         pvrdma_idx_ring_inc(&cq->ring_state->rx.cons_head, cq->ibcq.cqe);
 385
 386         return 0;
 387 }
 388
 389 /**
 390  * pvrdma_poll_cq - poll for work completion queue entries
 391  * @ibcq: completion queue
 392  * @num_entries: the maximum number of entries
 393  * @entry: pointer to work completion array
 394  *
 395  * @return: number of polled completion entries
 396  */
 397 int pvrdma_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc)
 398 {
 399         struct pvrdma_cq *cq = to_vcq(ibcq);
 400         struct pvrdma_qp *cur_qp = NULL;
 401         unsigned long flags;
 402         int npolled;
 403
 404         if (num_entries < 1 || wc == NULL)
 405                 return 0;
 406
 407         spin_lock_irqsave(&cq->cq_lock, flags);
 408         for (npolled = 0; npolled < num_entries; ++npolled) {
 409                 if (pvrdma_poll_one(cq, &cur_qp, wc + npolled))
 410                         break;
 411         }
 412
 413         spin_unlock_irqrestore(&cq->cq_lock, flags);
 414
 415         /* Ensure we do not return errors from poll_cq */
 416         return npolled;
 417 }