drivers/infiniband/hw/vmw_pvrdma/pvrdma_verbs.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/inet.h>
  48 #include <linux/io.h>
  49 #include <rdma/ib_addr.h>
  50 #include <rdma/ib_smi.h>
  51 #include <rdma/ib_user_verbs.h>
  52 #include <rdma/vmw_pvrdma-abi.h>
  53
  54 #include "pvrdma.h"
  55
  56 /**
  57  * pvrdma_query_device - query device
  58  * @ibdev: the device to query
  59  * @props: the device properties
  60  * @uhw: user data
  61  *
  62  * @return: 0 on success, otherwise negative errno
  63  */
  64 int pvrdma_query_device(struct ib_device *ibdev,
  65                         struct ib_device_attr *props,
  66                         struct ib_udata *uhw)
  67 {
  68         struct pvrdma_dev *dev = to_vdev(ibdev);
  69
  70         if (uhw->inlen || uhw->outlen)
  71                 return -EINVAL;
  72
  73         memset(props, 0, sizeof(*props));
  74
  75         props->fw_ver = dev->dsr->caps.fw_ver;
  76         props->sys_image_guid = dev->dsr->caps.sys_image_guid;
  77         props->max_mr_size = dev->dsr->caps.max_mr_size;
  78         props->page_size_cap = dev->dsr->caps.page_size_cap;
  79         props->vendor_id = dev->dsr->caps.vendor_id;
  80         props->vendor_part_id = dev->pdev->device;
  81         props->hw_ver = dev->dsr->caps.hw_ver;
  82         props->max_qp = dev->dsr->caps.max_qp;
  83         props->max_qp_wr = dev->dsr->caps.max_qp_wr;
  84         props->device_cap_flags = dev->dsr->caps.device_cap_flags;
  85         props->max_sge = dev->dsr->caps.max_sge;
  86         props->max_sge_rd = PVRDMA_GET_CAP(dev, dev->dsr->caps.max_sge,
  87                                            dev->dsr->caps.max_sge_rd);
  88         props->max_cq = dev->dsr->caps.max_cq;
  89         props->max_cqe = dev->dsr->caps.max_cqe;
  90         props->max_mr = dev->dsr->caps.max_mr;
  91         props->max_pd = dev->dsr->caps.max_pd;
  92         props->max_qp_rd_atom = dev->dsr->caps.max_qp_rd_atom;
  93         props->max_qp_init_rd_atom = dev->dsr->caps.max_qp_init_rd_atom;
  94         props->atomic_cap =
  95                 dev->dsr->caps.atomic_ops &
  96                 (PVRDMA_ATOMIC_OP_COMP_SWAP | PVRDMA_ATOMIC_OP_FETCH_ADD) ?
  97                 IB_ATOMIC_HCA : IB_ATOMIC_NONE;
  98         props->masked_atomic_cap = props->atomic_cap;
  99         props->max_ah = dev->dsr->caps.max_ah;
 100         props->max_pkeys = dev->dsr->caps.max_pkeys;
 101         props->local_ca_ack_delay = dev->dsr->caps.local_ca_ack_delay;
 102         if ((dev->dsr->caps.bmme_flags & PVRDMA_BMME_FLAG_LOCAL_INV) &&
 103             (dev->dsr->caps.bmme_flags & PVRDMA_BMME_FLAG_REMOTE_INV) &&
 104             (dev->dsr->caps.bmme_flags & PVRDMA_BMME_FLAG_FAST_REG_WR)) {
 105                 props->device_cap_flags |= IB_DEVICE_MEM_MGT_EXTENSIONS;
 106                 props->max_fast_reg_page_list_len = PVRDMA_GET_CAP(dev,
 107                                 PVRDMA_MAX_FAST_REG_PAGES,
 108                                 dev->dsr->caps.max_fast_reg_page_list_len);
 109         }
 110
 111         props->device_cap_flags |= IB_DEVICE_PORT_ACTIVE_EVENT |
 112                                    IB_DEVICE_RC_RNR_NAK_GEN;
 113
 114         return 0;
 115 }
 116
 117 /**
 118  * pvrdma_query_port - query device port attributes
 119  * @ibdev: the device to query
 120  * @port: the port number
 121  * @props: the device properties
 122  *
 123  * @return: 0 on success, otherwise negative errno
 124  */
 125 int pvrdma_query_port(struct ib_device *ibdev, u8 port,
 126                       struct ib_port_attr *props)
 127 {
 128         struct pvrdma_dev *dev = to_vdev(ibdev);
 129         union pvrdma_cmd_req req;
 130         union pvrdma_cmd_resp rsp;
 131         struct pvrdma_cmd_query_port *cmd = &req.query_port;
 132         struct pvrdma_cmd_query_port_resp *resp = &rsp.query_port_resp;
 133         int err;
 134
 135         memset(cmd, 0, sizeof(*cmd));
 136         cmd->hdr.cmd = PVRDMA_CMD_QUERY_PORT;
 137         cmd->port_num = port;
 138
 139         err = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_QUERY_PORT_RESP);
 140         if (err < 0) {
 141                 dev_warn(&dev->pdev->dev,
 142                          "could not query port, error: %d\n", err);
 143                 return err;
 144         }
 145
 146         /* props being zeroed by the caller, avoid zeroing it here */
 147
 148         props->state = pvrdma_port_state_to_ib(resp->attrs.state);
 149         props->max_mtu = pvrdma_mtu_to_ib(resp->attrs.max_mtu);
 150         props->active_mtu = pvrdma_mtu_to_ib(resp->attrs.active_mtu);
 151         props->gid_tbl_len = resp->attrs.gid_tbl_len;
 152         props->port_cap_flags =
 153                 pvrdma_port_cap_flags_to_ib(resp->attrs.port_cap_flags);
 154         props->port_cap_flags |= IB_PORT_CM_SUP | IB_PORT_IP_BASED_GIDS;
 155         props->max_msg_sz = resp->attrs.max_msg_sz;
 156         props->bad_pkey_cntr = resp->attrs.bad_pkey_cntr;
 157         props->qkey_viol_cntr = resp->attrs.qkey_viol_cntr;
 158         props->pkey_tbl_len = resp->attrs.pkey_tbl_len;
 159         props->lid = resp->attrs.lid;
 160         props->sm_lid = resp->attrs.sm_lid;
 161         props->lmc = resp->attrs.lmc;
 162         props->max_vl_num = resp->attrs.max_vl_num;
 163         props->sm_sl = resp->attrs.sm_sl;
 164         props->subnet_timeout = resp->attrs.subnet_timeout;
 165         props->init_type_reply = resp->attrs.init_type_reply;
 166         props->active_width = pvrdma_port_width_to_ib(resp->attrs.active_width);
 167         props->active_speed = pvrdma_port_speed_to_ib(resp->attrs.active_speed);
 168         props->phys_state = resp->attrs.phys_state;
 169
 170         return 0;
 171 }
 172
 173 /**
 174  * pvrdma_query_gid - query device gid
 175  * @ibdev: the device to query
 176  * @port: the port number
 177  * @index: the index
 178  * @gid: the device gid value
 179  *
 180  * @return: 0 on success, otherwise negative errno
 181  */
 182 int pvrdma_query_gid(struct ib_device *ibdev, u8 port, int index,
 183                      union ib_gid *gid)
 184 {
 185         struct pvrdma_dev *dev = to_vdev(ibdev);
 186
 187         if (index >= dev->dsr->caps.gid_tbl_len)
 188                 return -EINVAL;
 189
 190         memcpy(gid, &dev->sgid_tbl[index], sizeof(union ib_gid));
 191
 192         return 0;
 193 }
 194
 195 /**
 196  * pvrdma_query_pkey - query device port's P_Key table
 197  * @ibdev: the device to query
 198  * @port: the port number
 199  * @index: the index
 200  * @pkey: the device P_Key value
 201  *
 202  * @return: 0 on success, otherwise negative errno
 203  */
 204 int pvrdma_query_pkey(struct ib_device *ibdev, u8 port, u16 index,
 205                       u16 *pkey)
 206 {
 207         int err = 0;
 208         union pvrdma_cmd_req req;
 209         union pvrdma_cmd_resp rsp;
 210         struct pvrdma_cmd_query_pkey *cmd = &req.query_pkey;
 211
 212         memset(cmd, 0, sizeof(*cmd));
 213         cmd->hdr.cmd = PVRDMA_CMD_QUERY_PKEY;
 214         cmd->port_num = port;
 215         cmd->index = index;
 216
 217         err = pvrdma_cmd_post(to_vdev(ibdev), &req, &rsp,
 218                               PVRDMA_CMD_QUERY_PKEY_RESP);
 219         if (err < 0) {
 220                 dev_warn(&to_vdev(ibdev)->pdev->dev,
 221                          "could not query pkey, error: %d\n", err);
 222                 return err;
 223         }
 224
 225         *pkey = rsp.query_pkey_resp.pkey;
 226
 227         return 0;
 228 }
 229
 230 enum rdma_link_layer pvrdma_port_link_layer(struct ib_device *ibdev,
 231                                             u8 port)
 232 {
 233         return IB_LINK_LAYER_ETHERNET;
 234 }
 235
 236 int pvrdma_modify_device(struct ib_device *ibdev, int mask,
 237                          struct ib_device_modify *props)
 238 {
 239         unsigned long flags;
 240
 241         if (mask & ~(IB_DEVICE_MODIFY_SYS_IMAGE_GUID |
 242                      IB_DEVICE_MODIFY_NODE_DESC)) {
 243                 dev_warn(&to_vdev(ibdev)->pdev->dev,
 244                          "unsupported device modify mask %#x\n", mask);
 245                 return -EOPNOTSUPP;
 246         }
 247
 248         if (mask & IB_DEVICE_MODIFY_NODE_DESC) {
 249                 spin_lock_irqsave(&to_vdev(ibdev)->desc_lock, flags);
 250                 memcpy(ibdev->node_desc, props->node_desc, 64);
 251                 spin_unlock_irqrestore(&to_vdev(ibdev)->desc_lock, flags);
 252         }
 253
 254         if (mask & IB_DEVICE_MODIFY_SYS_IMAGE_GUID) {
 255                 mutex_lock(&to_vdev(ibdev)->port_mutex);
 256                 to_vdev(ibdev)->sys_image_guid =
 257                         cpu_to_be64(props->sys_image_guid);
 258                 mutex_unlock(&to_vdev(ibdev)->port_mutex);
 259         }
 260
 261         return 0;
 262 }
 263
 264 /**
 265  * pvrdma_modify_port - modify device port attributes
 266  * @ibdev: the device to modify
 267  * @port: the port number
 268  * @mask: attributes to modify
 269  * @props: the device properties
 270  *
 271  * @return: 0 on success, otherwise negative errno
 272  */
 273 int pvrdma_modify_port(struct ib_device *ibdev, u8 port, int mask,
 274                        struct ib_port_modify *props)
 275 {
 276         struct ib_port_attr attr;
 277         struct pvrdma_dev *vdev = to_vdev(ibdev);
 278         int ret;
 279
 280         if (mask & ~IB_PORT_SHUTDOWN) {
 281                 dev_warn(&vdev->pdev->dev,
 282                          "unsupported port modify mask %#x\n", mask);
 283                 return -EOPNOTSUPP;
 284         }
 285
 286         mutex_lock(&vdev->port_mutex);
 287         ret = ib_query_port(ibdev, port, &attr);
 288         if (ret)
 289                 goto out;
 290
 291         vdev->port_cap_mask |= props->set_port_cap_mask;
 292         vdev->port_cap_mask &= ~props->clr_port_cap_mask;
 293
 294         if (mask & IB_PORT_SHUTDOWN)
 295                 vdev->ib_active = false;
 296
 297 out:
 298         mutex_unlock(&vdev->port_mutex);
 299         return ret;
 300 }
 301
 302 /**
 303  * pvrdma_alloc_ucontext - allocate ucontext
 304  * @ibdev: the IB device
 305  * @udata: user data
 306  *
 307  * @return: the ib_ucontext pointer on success, otherwise errno.
 308  */
 309 struct ib_ucontext *pvrdma_alloc_ucontext(struct ib_device *ibdev,
 310                                           struct ib_udata *udata)
 311 {
 312         struct pvrdma_dev *vdev = to_vdev(ibdev);
 313         struct pvrdma_ucontext *context;
 314         union pvrdma_cmd_req req;
 315         union pvrdma_cmd_resp rsp;
 316         struct pvrdma_cmd_create_uc *cmd = &req.create_uc;
 317         struct pvrdma_cmd_create_uc_resp *resp = &rsp.create_uc_resp;
 318         struct pvrdma_alloc_ucontext_resp uresp = {0};
 319         int ret;
 320         void *ptr;
 321
 322         if (!vdev->ib_active)
 323                 return ERR_PTR(-EAGAIN);
 324
 325         context = kmalloc(sizeof(*context), GFP_KERNEL);
 326         if (!context)
 327                 return ERR_PTR(-ENOMEM);
 328
 329         context->dev = vdev;
 330         ret = pvrdma_uar_alloc(vdev, &context->uar);
 331         if (ret) {
 332                 kfree(context);
 333                 return ERR_PTR(-ENOMEM);
 334         }
 335
 336         /* get ctx_handle from host */
 337         memset(cmd, 0, sizeof(*cmd));
 338         cmd->pfn = context->uar.pfn;
 339         cmd->hdr.cmd = PVRDMA_CMD_CREATE_UC;
 340         ret = pvrdma_cmd_post(vdev, &req, &rsp, PVRDMA_CMD_CREATE_UC_RESP);
 341         if (ret < 0) {
 342                 dev_warn(&vdev->pdev->dev,
 343                          "could not create ucontext, error: %d\n", ret);
 344                 ptr = ERR_PTR(ret);
 345                 goto err;
 346         }
 347
 348         context->ctx_handle = resp->ctx_handle;
 349
 350         /* copy back to user */
 351         uresp.qp_tab_size = vdev->dsr->caps.max_qp;
 352         ret = ib_copy_to_udata(udata, &uresp, sizeof(uresp));
 353         if (ret) {
 354                 pvrdma_uar_free(vdev, &context->uar);
 355                 context->ibucontext.device = ibdev;
 356                 pvrdma_dealloc_ucontext(&context->ibucontext);
 357                 return ERR_PTR(-EFAULT);
 358         }
 359
 360         return &context->ibucontext;
 361
 362 err:
 363         pvrdma_uar_free(vdev, &context->uar);
 364         kfree(context);
 365         return ptr;
 366 }
 367
 368 /**
 369  * pvrdma_dealloc_ucontext - deallocate ucontext
 370  * @ibcontext: the ucontext
 371  *
 372  * @return: 0 on success, otherwise errno.
 373  */
 374 int pvrdma_dealloc_ucontext(struct ib_ucontext *ibcontext)
 375 {
 376         struct pvrdma_ucontext *context = to_vucontext(ibcontext);
 377         union pvrdma_cmd_req req;
 378         struct pvrdma_cmd_destroy_uc *cmd = &req.destroy_uc;
 379         int ret;
 380
 381         memset(cmd, 0, sizeof(*cmd));
 382         cmd->hdr.cmd = PVRDMA_CMD_DESTROY_UC;
 383         cmd->ctx_handle = context->ctx_handle;
 384
 385         ret = pvrdma_cmd_post(context->dev, &req, NULL, 0);
 386         if (ret < 0)
 387                 dev_warn(&context->dev->pdev->dev,
 388                          "destroy ucontext failed, error: %d\n", ret);
 389
 390         /* Free the UAR even if the device command failed */
 391         pvrdma_uar_free(to_vdev(ibcontext->device), &context->uar);
 392         kfree(context);
 393
 394         return ret;
 395 }
 396
 397 /**
 398  * pvrdma_mmap - create mmap region
 399  * @ibcontext: the user context
 400  * @vma: the VMA
 401  *
 402  * @return: 0 on success, otherwise errno.
 403  */
 404 int pvrdma_mmap(struct ib_ucontext *ibcontext, struct vm_area_struct *vma)
 405 {
 406         struct pvrdma_ucontext *context = to_vucontext(ibcontext);
 407         unsigned long start = vma->vm_start;
 408         unsigned long size = vma->vm_end - vma->vm_start;
 409         unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
 410
 411         dev_dbg(&context->dev->pdev->dev, "create mmap region\n");
 412
 413         if ((size != PAGE_SIZE) || (offset & ~PAGE_MASK)) {
 414                 dev_warn(&context->dev->pdev->dev,
 415                          "invalid params for mmap region\n");
 416                 return -EINVAL;
 417         }
 418
 419         /* Map UAR to kernel space, VM_LOCKED? */
 420         vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;
 421         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 422         if (io_remap_pfn_range(vma, start, context->uar.pfn, size,
 423                                vma->vm_page_prot))
 424                 return -EAGAIN;
 425
 426         return 0;
 427 }
 428
 429 /**
 430  * pvrdma_alloc_pd - allocate protection domain
 431  * @ibdev: the IB device
 432  * @context: user context
 433  * @udata: user data
 434  *
 435  * @return: the ib_pd protection domain pointer on success, otherwise errno.
 436  */
 437 struct ib_pd *pvrdma_alloc_pd(struct ib_device *ibdev,
 438                               struct ib_ucontext *context,
 439                               struct ib_udata *udata)
 440 {
 441         struct pvrdma_pd *pd;
 442         struct pvrdma_dev *dev = to_vdev(ibdev);
 443         union pvrdma_cmd_req req;
 444         union pvrdma_cmd_resp rsp;
 445         struct pvrdma_cmd_create_pd *cmd = &req.create_pd;
 446         struct pvrdma_cmd_create_pd_resp *resp = &rsp.create_pd_resp;
 447         int ret;
 448         void *ptr;
 449
 450         /* Check allowed max pds */
 451         if (!atomic_add_unless(&dev->num_pds, 1, dev->dsr->caps.max_pd))
 452                 return ERR_PTR(-ENOMEM);
 453
 454         pd = kmalloc(sizeof(*pd), GFP_KERNEL);
 455         if (!pd) {
 456                 ptr = ERR_PTR(-ENOMEM);
 457                 goto err;
 458         }
 459
 460         memset(cmd, 0, sizeof(*cmd));
 461         cmd->hdr.cmd = PVRDMA_CMD_CREATE_PD;
 462         cmd->ctx_handle = (context) ? to_vucontext(context)->ctx_handle : 0;
 463         ret = pvrdma_cmd_post(dev, &req, &rsp, PVRDMA_CMD_CREATE_PD_RESP);
 464         if (ret < 0) {
 465                 dev_warn(&dev->pdev->dev,
 466                          "failed to allocate protection domain, error: %d\n",
 467                          ret);
 468                 ptr = ERR_PTR(ret);
 469                 goto freepd;
 470         }
 471
 472         pd->privileged = !context;
 473         pd->pd_handle = resp->pd_handle;
 474         pd->pdn = resp->pd_handle;
 475
 476         if (context) {
 477                 if (ib_copy_to_udata(udata, &pd->pdn, sizeof(__u32))) {
 478                         dev_warn(&dev->pdev->dev,
 479                                  "failed to copy back protection domain\n");
 480                         pvrdma_dealloc_pd(&pd->ibpd);
 481                         return ERR_PTR(-EFAULT);
 482                 }
 483         }
 484
 485         /* u32 pd handle */
 486         return &pd->ibpd;
 487
 488 freepd:
 489         kfree(pd);
 490 err:
 491         atomic_dec(&dev->num_pds);
 492         return ptr;
 493 }
 494
 495 /**
 496  * pvrdma_dealloc_pd - deallocate protection domain
 497  * @pd: the protection domain to be released
 498  *
 499  * @return: 0 on success, otherwise errno.
 500  */
 501 int pvrdma_dealloc_pd(struct ib_pd *pd)
 502 {
 503         struct pvrdma_dev *dev = to_vdev(pd->device);
 504         union pvrdma_cmd_req req;
 505         struct pvrdma_cmd_destroy_pd *cmd = &req.destroy_pd;
 506         int ret;
 507
 508         memset(cmd, 0, sizeof(*cmd));
 509         cmd->hdr.cmd = PVRDMA_CMD_DESTROY_PD;
 510         cmd->pd_handle = to_vpd(pd)->pd_handle;
 511
 512         ret = pvrdma_cmd_post(dev, &req, NULL, 0);
 513         if (ret)
 514                 dev_warn(&dev->pdev->dev,
 515                          "could not dealloc protection domain, error: %d\n",
 516                          ret);
 517
 518         kfree(to_vpd(pd));
 519         atomic_dec(&dev->num_pds);
 520
 521         return 0;
 522 }
 523
 524 /**
 525  * pvrdma_create_ah - create an address handle
 526  * @pd: the protection domain
 527  * @ah_attr: the attributes of the AH
 528  * @udata: user data blob
 529  *
 530  * @return: the ib_ah pointer on success, otherwise errno.
 531  */
 532 struct ib_ah *pvrdma_create_ah(struct ib_pd *pd, struct rdma_ah_attr *ah_attr,
 533                                struct ib_udata *udata)
 534 {
 535         struct pvrdma_dev *dev = to_vdev(pd->device);
 536         struct pvrdma_ah *ah;
 537         const struct ib_global_route *grh;
 538         u8 port_num = rdma_ah_get_port_num(ah_attr);
 539
 540         if (!(rdma_ah_get_ah_flags(ah_attr) & IB_AH_GRH))
 541                 return ERR_PTR(-EINVAL);
 542
 543         grh = rdma_ah_read_grh(ah_attr);
 544         if ((ah_attr->type != RDMA_AH_ATTR_TYPE_ROCE)  ||
 545             rdma_is_multicast_addr((struct in6_addr *)grh->dgid.raw))
 546                 return ERR_PTR(-EINVAL);
 547
 548         if (!atomic_add_unless(&dev->num_ahs, 1, dev->dsr->caps.max_ah))
 549                 return ERR_PTR(-ENOMEM);
 550
 551         ah = kzalloc(sizeof(*ah), GFP_KERNEL);
 552         if (!ah) {
 553                 atomic_dec(&dev->num_ahs);
 554                 return ERR_PTR(-ENOMEM);
 555         }
 556
 557         ah->av.port_pd = to_vpd(pd)->pd_handle | (port_num << 24);
 558         ah->av.src_path_bits = rdma_ah_get_path_bits(ah_attr);
 559         ah->av.src_path_bits |= 0x80;
 560         ah->av.gid_index = grh->sgid_index;
 561         ah->av.hop_limit = grh->hop_limit;
 562         ah->av.sl_tclass_flowlabel = (grh->traffic_class << 20) |
 563                                       grh->flow_label;
 564         memcpy(ah->av.dgid, grh->dgid.raw, 16);
 565         memcpy(ah->av.dmac, ah_attr->roce.dmac, ETH_ALEN);
 566
 567         ah->ibah.device = pd->device;
 568         ah->ibah.pd = pd;
 569         ah->ibah.uobject = NULL;
 570
 571         return &ah->ibah;
 572 }
 573
 574 /**
 575  * pvrdma_destroy_ah - destroy an address handle
 576  * @ah: the address handle to destroyed
 577  *
 578  * @return: 0 on success.
 579  */
 580 int pvrdma_destroy_ah(struct ib_ah *ah)
 581 {
 582         struct pvrdma_dev *dev = to_vdev(ah->device);
 583
 584         kfree(to_vah(ah));
 585         atomic_dec(&dev->num_ahs);
 586
 587         return 0;
 588 }