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 ucmd;
 118
 119         BUILD_BUG_ON(sizeof(struct pvrdma_cqe) != 64);
 120
 121         entries = roundup_pow_of_two(entries);
 122         if (entries < 1 || entries > dev->dsr->caps.max_cqe)
 123                 return ERR_PTR(-EINVAL);
 124
 125         if (!atomic_add_unless(&dev->num_cqs, 1, dev->dsr->caps.max_cq))
 126                 return ERR_PTR(-ENOMEM);
 127
 128         cq = kzalloc(sizeof(*cq), GFP_KERNEL);
 129         if (!cq) {
 130                 atomic_dec(&dev->num_cqs);
 131                 return ERR_PTR(-ENOMEM);
 132         }
 133
 134         cq->ibcq.cqe = entries;
 135
 136         if (context) {
 137                 if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd))) {
 138                         ret = -EFAULT;
 139                         goto err_cq;
 140                 }
 141
 142                 cq->umem = ib_umem_get(context, ucmd.buf_addr, ucmd.buf_size,
 143                                        IB_ACCESS_LOCAL_WRITE, 1);
 144                 if (IS_ERR(cq->umem)) {
 145                         ret = PTR_ERR(cq->umem);
 146                         goto err_cq;
 147                 }
 148
 149                 npages = ib_umem_page_count(cq->umem);
 150         } else {
 151                 cq->is_kernel = true;
 152
 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         atomic_set(&cq->refcnt, 1);
 182         init_waitqueue_head(&cq->wait);
 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         spin_lock_irqsave(&dev->cq_tbl_lock, flags);
 202         dev->cq_tbl[cq->cq_handle % dev->dsr->caps.max_cq] = cq;
 203         spin_unlock_irqrestore(&dev->cq_tbl_lock, flags);
 204
 205         if (context) {
 206                 cq->uar = &(to_vucontext(context)->uar);
 207
 208                 /* Copy udata back. */
 209                 if (ib_copy_to_udata(udata, &cq->cq_handle, sizeof(__u32))) {
 210                         dev_warn(&dev->pdev->dev,
 211                                  "failed to copy back udata\n");
 212                         pvrdma_destroy_cq(&cq->ibcq);
 213                         return ERR_PTR(-EINVAL);
 214                 }
 215         }
 216
 217         return &cq->ibcq;
 218
 219 err_page_dir:
 220         pvrdma_page_dir_cleanup(dev, &cq->pdir);
 221 err_umem:
 222         if (context)
 223                 ib_umem_release(cq->umem);
 224 err_cq:
 225         atomic_dec(&dev->num_cqs);
 226         kfree(cq);
 227
 228         return ERR_PTR(ret);
 229 }
 230
 231 static void pvrdma_free_cq(struct pvrdma_dev *dev, struct pvrdma_cq *cq)
 232 {
 233         atomic_dec(&cq->refcnt);
 234         wait_event(cq->wait, !atomic_read(&cq->refcnt));
 235
 236         if (!cq->is_kernel)
 237                 ib_umem_release(cq->umem);
 238
 239         pvrdma_page_dir_cleanup(dev, &cq->pdir);
 240         kfree(cq);
 241 }
 242
 243 /**
 244  * pvrdma_destroy_cq - destroy completion queue
 245  * @cq: the completion queue to destroy.
 246  *
 247  * @return: 0 for success.
 248  */
 249 int pvrdma_destroy_cq(struct ib_cq *cq)
 250 {
 251         struct pvrdma_cq *vcq = to_vcq(cq);
 252         union pvrdma_cmd_req req;
 253         struct pvrdma_cmd_destroy_cq *cmd = &req.destroy_cq;
 254         struct pvrdma_dev *dev = to_vdev(cq->device);
 255         unsigned long flags;
 256         int ret;
 257
 258         memset(cmd, 0, sizeof(*cmd));
 259         cmd->hdr.cmd = PVRDMA_CMD_DESTROY_CQ;
 260         cmd->cq_handle = vcq->cq_handle;
 261
 262         ret = pvrdma_cmd_post(dev, &req, NULL, 0);
 263         if (ret < 0)
 264                 dev_warn(&dev->pdev->dev,
 265                          "could not destroy completion queue, error: %d\n",
 266                          ret);
 267
 268         /* free cq's resources */
 269         spin_lock_irqsave(&dev->cq_tbl_lock, flags);
 270         dev->cq_tbl[vcq->cq_handle] = NULL;
 271         spin_unlock_irqrestore(&dev->cq_tbl_lock, flags);
 272
 273         pvrdma_free_cq(dev, vcq);
 274         atomic_dec(&dev->num_cqs);
 275
 276         return ret;
 277 }
 278
 279 /**
 280  * pvrdma_modify_cq - modify the CQ moderation parameters
 281  * @ibcq: the CQ to modify
 282  * @cq_count: number of CQEs that will trigger an event
 283  * @cq_period: max period of time in usec before triggering an event
 284  *
 285  * @return: -EOPNOTSUPP as CQ resize is not supported.
 286  */
 287 int pvrdma_modify_cq(struct ib_cq *cq, u16 cq_count, u16 cq_period)
 288 {
 289         return -EOPNOTSUPP;
 290 }
 291
 292 static inline struct pvrdma_cqe *get_cqe(struct pvrdma_cq *cq, int i)
 293 {
 294         return (struct pvrdma_cqe *)pvrdma_page_dir_get_ptr(
 295                                         &cq->pdir,
 296                                         cq->offset +
 297                                         sizeof(struct pvrdma_cqe) * i);
 298 }
 299
 300 void _pvrdma_flush_cqe(struct pvrdma_qp *qp, struct pvrdma_cq *cq)
 301 {
 302         int head;
 303         int has_data;
 304
 305         if (!cq->is_kernel)
 306                 return;
 307
 308         /* Lock held */
 309         has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
 310                                             cq->ibcq.cqe, &head);
 311         if (unlikely(has_data > 0)) {
 312                 int items;
 313                 int curr;
 314                 int tail = pvrdma_idx(&cq->ring_state->rx.prod_tail,
 315                                       cq->ibcq.cqe);
 316                 struct pvrdma_cqe *cqe;
 317                 struct pvrdma_cqe *curr_cqe;
 318
 319                 items = (tail > head) ? (tail - head) :
 320                         (cq->ibcq.cqe - head + tail);
 321                 curr = --tail;
 322                 while (items-- > 0) {
 323                         if (curr < 0)
 324                                 curr = cq->ibcq.cqe - 1;
 325                         if (tail < 0)
 326                                 tail = cq->ibcq.cqe - 1;
 327                         curr_cqe = get_cqe(cq, curr);
 328                         if ((curr_cqe->qp & 0xFFFF) != qp->qp_handle) {
 329                                 if (curr != tail) {
 330                                         cqe = get_cqe(cq, tail);
 331                                         *cqe = *curr_cqe;
 332                                 }
 333                                 tail--;
 334                         } else {
 335                                 pvrdma_idx_ring_inc(
 336                                         &cq->ring_state->rx.cons_head,
 337                                         cq->ibcq.cqe);
 338                         }
 339                         curr--;
 340                 }
 341         }
 342 }
 343
 344 static int pvrdma_poll_one(struct pvrdma_cq *cq, struct pvrdma_qp **cur_qp,
 345                            struct ib_wc *wc)
 346 {
 347         struct pvrdma_dev *dev = to_vdev(cq->ibcq.device);
 348         int has_data;
 349         unsigned int head;
 350         bool tried = false;
 351         struct pvrdma_cqe *cqe;
 352
 353 retry:
 354         has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
 355                                             cq->ibcq.cqe, &head);
 356         if (has_data == 0) {
 357                 if (tried)
 358                         return -EAGAIN;
 359
 360                 pvrdma_write_uar_cq(dev, cq->cq_handle | PVRDMA_UAR_CQ_POLL);
 361
 362                 tried = true;
 363                 goto retry;
 364         } else if (has_data == PVRDMA_INVALID_IDX) {
 365                 dev_err(&dev->pdev->dev, "CQ ring state invalid\n");
 366                 return -EAGAIN;
 367         }
 368
 369         cqe = get_cqe(cq, head);
 370
 371         /* Ensure cqe is valid. */
 372         rmb();
 373         if (dev->qp_tbl[cqe->qp & 0xffff])
 374                 *cur_qp = (struct pvrdma_qp *)dev->qp_tbl[cqe->qp & 0xffff];
 375         else
 376                 return -EAGAIN;
 377
 378         wc->opcode = pvrdma_wc_opcode_to_ib(cqe->opcode);
 379         wc->status = pvrdma_wc_status_to_ib(cqe->status);
 380         wc->wr_id = cqe->wr_id;
 381         wc->qp = &(*cur_qp)->ibqp;
 382         wc->byte_len = cqe->byte_len;
 383         wc->ex.imm_data = cqe->imm_data;
 384         wc->src_qp = cqe->src_qp;
 385         wc->wc_flags = pvrdma_wc_flags_to_ib(cqe->wc_flags);
 386         wc->pkey_index = cqe->pkey_index;
 387         wc->slid = cqe->slid;
 388         wc->sl = cqe->sl;
 389         wc->dlid_path_bits = cqe->dlid_path_bits;
 390         wc->port_num = cqe->port_num;
 391         wc->vendor_err = cqe->vendor_err;
 392
 393         /* Update shared ring state */
 394         pvrdma_idx_ring_inc(&cq->ring_state->rx.cons_head, cq->ibcq.cqe);
 395
 396         return 0;
 397 }
 398
 399 /**
 400  * pvrdma_poll_cq - poll for work completion queue entries
 401  * @ibcq: completion queue
 402  * @num_entries: the maximum number of entries
 403  * @entry: pointer to work completion array
 404  *
 405  * @return: number of polled completion entries
 406  */
 407 int pvrdma_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc)
 408 {
 409         struct pvrdma_cq *cq = to_vcq(ibcq);
 410         struct pvrdma_qp *cur_qp = NULL;
 411         unsigned long flags;
 412         int npolled;
 413
 414         if (num_entries < 1 || wc == NULL)
 415                 return 0;
 416
 417         spin_lock_irqsave(&cq->cq_lock, flags);
 418         for (npolled = 0; npolled < num_entries; ++npolled) {
 419                 if (pvrdma_poll_one(cq, &cur_qp, wc + npolled))
 420                         break;
 421         }
 422
 423         spin_unlock_irqrestore(&cq->cq_lock, flags);
 424
 425         /* Ensure we do not return errors from poll_cq */
 426         return npolled;
 427 }
 428
 429 /**
 430  * pvrdma_resize_cq - resize CQ
 431  * @ibcq: the completion queue
 432  * @entries: CQ entries
 433  * @udata: user data
 434  *
 435  * @return: -EOPNOTSUPP as CQ resize is not supported.
 436  */
 437 int pvrdma_resize_cq(struct ib_cq *ibcq, int entries, struct ib_udata *udata)
 438 {
 439         return -EOPNOTSUPP;
 440 }