ClabureDB: Classified Bug-Reports Database

   /*
    * Copyright (c) 2005 Cisco Systems.  All rights reserved.
    *
    * This software is available to you under a choice of one of two
    * licenses.  You may choose to be licensed under the terms of the GNU
    * General Public License (GPL) Version 2, available from the file
    * COPYING in the main directory of this source tree, or the
    * OpenIB.org BSD license below:
    *
   *     Redistribution and use in source and binary forms, with or
   *     without modification, are permitted provided that the following
   *     conditions are met:
   *
   *      - Redistributions of source code must retain the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer.
   *
   *      - Redistributions in binary form must reproduce the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer in the documentation and/or other materials
   *        provided with the distribution.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/slab.h>
  #include <linux/err.h>
  #include <linux/string.h>
  #include <linux/parser.h>
  #include <linux/random.h>
  #include <linux/jiffies.h>
  
  #include <asm/atomic.h>
  
  #include <scsi/scsi.h>
  #include <scsi/scsi_device.h>
  #include <scsi/scsi_dbg.h>
  #include <scsi/srp.h>
  #include <scsi/scsi_transport_srp.h>
  
  #include "ib_srp.h"
  
  #define DRV_NAME        "ib_srp"
  #define PFX                DRV_NAME ": "
  #define DRV_VERSION        "0.2"
  #define DRV_RELDATE        "November 1, 2005"
  
  MODULE_AUTHOR("Roland Dreier");
  MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
                     "v" DRV_VERSION " (" DRV_RELDATE ")");
  MODULE_LICENSE("Dual BSD/GPL");
  
  static int srp_sg_tablesize = SRP_DEF_SG_TABLESIZE;
  static int srp_max_iu_len;
  
  module_param(srp_sg_tablesize, int, 0444);
  MODULE_PARM_DESC(srp_sg_tablesize,
                   "Max number of gather/scatter entries per I/O (default is 12, max 255)");
  
  static int topspin_workarounds = 1;
  
  module_param(topspin_workarounds, int, 0444);
  MODULE_PARM_DESC(topspin_workarounds,
                   "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
  
  static int mellanox_workarounds = 1;
  
  module_param(mellanox_workarounds, int, 0444);
  MODULE_PARM_DESC(mellanox_workarounds,
                   "Enable workarounds for Mellanox SRP target bugs if != 0");
  
  static void srp_add_one(struct ib_device *device);
  static void srp_remove_one(struct ib_device *device);
  static void srp_completion(struct ib_cq *cq, void *target_ptr);
  static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
  
  static struct scsi_transport_template *ib_srp_transport_template;
  
  static struct ib_client srp_client = {
          .name   = "srp",
          .add    = srp_add_one,
          .remove = srp_remove_one
  };
  
  static struct ib_sa_client srp_sa_client;
  
  static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
  {
          return (struct srp_target_port *) host->hostdata;
  }
 
 static const char *srp_target_info(struct Scsi_Host *host)
 {
         return host_to_target(host)->target_name;
 }
 
 static int srp_target_is_topspin(struct srp_target_port *target)
 {
         static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
         static const u8 cisco_oui[3]   = { 0x00, 0x1b, 0x0d };
 
         return topspin_workarounds &&
                 (!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
                  !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
 }
 
 static int srp_target_is_mellanox(struct srp_target_port *target)
 {
         static const u8 mellanox_oui[3] = { 0x00, 0x02, 0xc9 };
 
         return mellanox_workarounds &&
                 !memcmp(&target->ioc_guid, mellanox_oui, sizeof mellanox_oui);
 }
 
 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
                                    gfp_t gfp_mask,
                                    enum dma_data_direction direction)
 {
         struct srp_iu *iu;
 
         iu = kmalloc(sizeof *iu, gfp_mask);
         if (!iu)
                 goto out;
 
         iu->buf = kzalloc(size, gfp_mask);
         if (!iu->buf)
                 goto out_free_iu;
 
         iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
                                     direction);
         if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
                 goto out_free_buf;
 
         iu->size      = size;
         iu->direction = direction;
 
         return iu;
 
 out_free_buf:
         kfree(iu->buf);
 out_free_iu:
         kfree(iu);
 out:
         return NULL;
 }
 
 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
 {
         if (!iu)
                 return;
 
         ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
                             iu->direction);
         kfree(iu->buf);
         kfree(iu);
 }
 
 static void srp_qp_event(struct ib_event *event, void *context)
 {
         printk(KERN_ERR PFX "QP event %d\n", event->event);
 }
 
 static int srp_init_qp(struct srp_target_port *target,
                        struct ib_qp *qp)
 {
         struct ib_qp_attr *attr;
         int ret;
 
         attr = kmalloc(sizeof *attr, GFP_KERNEL);
         if (!attr)
                 return -ENOMEM;
 
         ret = ib_find_pkey(target->srp_host->srp_dev->dev,
                            target->srp_host->port,
                            be16_to_cpu(target->path.pkey),
                            &attr->pkey_index);
         if (ret)
                 goto out;
 
         attr->qp_state        = IB_QPS_INIT;
         attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
                                     IB_ACCESS_REMOTE_WRITE);
         attr->port_num        = target->srp_host->port;
 
         ret = ib_modify_qp(qp, attr,
                            IB_QP_STATE                |
                            IB_QP_PKEY_INDEX        |
                            IB_QP_ACCESS_FLAGS        |
                            IB_QP_PORT);
 
 out:
         kfree(attr);
         return ret;
 }
 
 static int srp_new_cm_id(struct srp_target_port *target)
 {
         struct ib_cm_id *new_cm_id;
 
         new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
                                     srp_cm_handler, target);
         if (IS_ERR(new_cm_id))
                 return PTR_ERR(new_cm_id);
 
         if (target->cm_id)
                 ib_destroy_cm_id(target->cm_id);
         target->cm_id = new_cm_id;
 
         return 0;
 }
 
 static int srp_create_target_ib(struct srp_target_port *target)
 {
         struct ib_qp_init_attr *init_attr;
         int ret;
 
         init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
         if (!init_attr)
                 return -ENOMEM;
 
         target->cq = ib_create_cq(target->srp_host->srp_dev->dev,
                                   srp_completion, NULL, target, SRP_CQ_SIZE, 0);
         if (IS_ERR(target->cq)) {
                 ret = PTR_ERR(target->cq);
                 goto out;
         }
 
         ib_req_notify_cq(target->cq, IB_CQ_NEXT_COMP);
 
         init_attr->event_handler       = srp_qp_event;
         init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
         init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
         init_attr->cap.max_recv_sge    = 1;
         init_attr->cap.max_send_sge    = 1;
         init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;
         init_attr->qp_type             = IB_QPT_RC;
         init_attr->send_cq             = target->cq;
         init_attr->recv_cq             = target->cq;
 
         target->qp = ib_create_qp(target->srp_host->srp_dev->pd, init_attr);
         if (IS_ERR(target->qp)) {
                 ret = PTR_ERR(target->qp);
                 ib_destroy_cq(target->cq);
                 goto out;
         }
 
         ret = srp_init_qp(target, target->qp);
         if (ret) {
                 ib_destroy_qp(target->qp);
                 ib_destroy_cq(target->cq);
                 goto out;
         }
 
 out:
         kfree(init_attr);
         return ret;
 }
 
 static void srp_free_target_ib(struct srp_target_port *target)
 {
         int i;
 
         ib_destroy_qp(target->qp);
         ib_destroy_cq(target->cq);
 
         for (i = 0; i < SRP_RQ_SIZE; ++i)
                 srp_free_iu(target->srp_host, target->rx_ring[i]);
         for (i = 0; i < SRP_SQ_SIZE + 1; ++i)
                 srp_free_iu(target->srp_host, target->tx_ring[i]);
 }
 
 static void srp_path_rec_completion(int status,
                                     struct ib_sa_path_rec *pathrec,
                                     void *target_ptr)
 {
         struct srp_target_port *target = target_ptr;
 
         target->status = status;
         if (status)
                 shost_printk(KERN_ERR, target->scsi_host,
                              PFX "Got failed path rec status %d\n", status);
         else
                 target->path = *pathrec;
         complete(&target->done);
 }
 
 static int srp_lookup_path(struct srp_target_port *target)
 {
         target->path.numb_path = 1;
 
         init_completion(&target->done);
 
         target->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
                                                    target->srp_host->srp_dev->dev,
                                                    target->srp_host->port,
                                                    &target->path,
                                                    IB_SA_PATH_REC_SERVICE_ID        |
                                                    IB_SA_PATH_REC_DGID                |
                                                    IB_SA_PATH_REC_SGID                |
                                                    IB_SA_PATH_REC_NUMB_PATH        |
                                                    IB_SA_PATH_REC_PKEY,
                                                    SRP_PATH_REC_TIMEOUT_MS,
                                                    GFP_KERNEL,
                                                    srp_path_rec_completion,
                                                    target, &target->path_query);
         if (target->path_query_id < 0)
                 return target->path_query_id;
 
         wait_for_completion(&target->done);
 
         if (target->status < 0)
                 shost_printk(KERN_WARNING, target->scsi_host,
                              PFX "Path record query failed\n");
 
         return target->status;
 }
 
 static int srp_send_req(struct srp_target_port *target)
 {
         struct {
                 struct ib_cm_req_param param;
                 struct srp_login_req   priv;
         } *req = NULL;
         int status;
 
         req = kzalloc(sizeof *req, GFP_KERNEL);
         if (!req)
                 return -ENOMEM;
 
         req->param.primary_path               = &target->path;
         req->param.alternate_path               = NULL;
         req->param.service_id                       = target->service_id;
         req->param.qp_num                       = target->qp->qp_num;
         req->param.qp_type                       = target->qp->qp_type;
         req->param.private_data               = &req->priv;
         req->param.private_data_len               = sizeof req->priv;
         req->param.flow_control               = 1;
 
         get_random_bytes(&req->param.starting_psn, 4);
         req->param.starting_psn              &= 0xffffff;
 
         /*
          * Pick some arbitrary defaults here; we could make these
          * module parameters if anyone cared about setting them.
          */
         req->param.responder_resources              = 4;
         req->param.remote_cm_response_timeout = 20;
         req->param.local_cm_response_timeout  = 20;
         req->param.retry_count                       = 7;
         req->param.rnr_retry_count               = 7;
         req->param.max_cm_retries               = 15;
 
         req->priv.opcode             = SRP_LOGIN_REQ;
         req->priv.tag                = 0;
         req->priv.req_it_iu_len = cpu_to_be32(srp_max_iu_len);
         req->priv.req_buf_fmt         = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
                                               SRP_BUF_FORMAT_INDIRECT);
         /*
          * In the published SRP specification (draft rev. 16a), the
          * port identifier format is 8 bytes of ID extension followed
          * by 8 bytes of GUID.  Older drafts put the two halves in the
          * opposite order, so that the GUID comes first.
          *
          * Targets conforming to these obsolete drafts can be
          * recognized by the I/O Class they report.
          */
         if (target->io_class == SRP_REV10_IB_IO_CLASS) {
                 memcpy(req->priv.initiator_port_id,
                        &target->path.sgid.global.interface_id, 8);
                 memcpy(req->priv.initiator_port_id + 8,
                        &target->initiator_ext, 8);
                 memcpy(req->priv.target_port_id,     &target->ioc_guid, 8);
                 memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
         } else {
                 memcpy(req->priv.initiator_port_id,
                        &target->initiator_ext, 8);
                 memcpy(req->priv.initiator_port_id + 8,
                        &target->path.sgid.global.interface_id, 8);
                 memcpy(req->priv.target_port_id,     &target->id_ext, 8);
                 memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
         }
 
         /*
          * Topspin/Cisco SRP targets will reject our login unless we
          * zero out the first 8 bytes of our initiator port ID and set
          * the second 8 bytes to the local node GUID.
          */
         if (srp_target_is_topspin(target)) {
                 shost_printk(KERN_DEBUG, target->scsi_host,
                              PFX "Topspin/Cisco initiator port ID workaround "
                              "activated for target GUID %016llx\n",
                              (unsigned long long) be64_to_cpu(target->ioc_guid));
                 memset(req->priv.initiator_port_id, 0, 8);
                 memcpy(req->priv.initiator_port_id + 8,
                        &target->srp_host->srp_dev->dev->node_guid, 8);
         }
 
         status = ib_send_cm_req(target->cm_id, &req->param);
 
         kfree(req);
 
         return status;
 }
 
 static void srp_disconnect_target(struct srp_target_port *target)
 {
         /* XXX should send SRP_I_LOGOUT request */
 
         init_completion(&target->done);
         if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
                 shost_printk(KERN_DEBUG, target->scsi_host,
                              PFX "Sending CM DREQ failed\n");
                 return;
         }
         wait_for_completion(&target->done);
 }
 
 static void srp_remove_work(struct work_struct *work)
 {
         struct srp_target_port *target =
                 container_of(work, struct srp_target_port, work);
 
         spin_lock_irq(target->scsi_host->host_lock);
         if (target->state != SRP_TARGET_DEAD) {
                 spin_unlock_irq(target->scsi_host->host_lock);
                 return;
         }
         target->state = SRP_TARGET_REMOVED;
         spin_unlock_irq(target->scsi_host->host_lock);
 
         spin_lock(&target->srp_host->target_lock);
         list_del(&target->list);
         spin_unlock(&target->srp_host->target_lock);
 
         srp_remove_host(target->scsi_host);
         scsi_remove_host(target->scsi_host);
         ib_destroy_cm_id(target->cm_id);
         srp_free_target_ib(target);
         scsi_host_put(target->scsi_host);
 }
 
 static int srp_connect_target(struct srp_target_port *target)
 {
         int retries = 3;
         int ret;
 
         ret = srp_lookup_path(target);
         if (ret)
                 return ret;
 
         while (1) {
                 init_completion(&target->done);
                 ret = srp_send_req(target);
                 if (ret)
                         return ret;
                 wait_for_completion(&target->done);
 
                 /*
                  * The CM event handling code will set status to
                  * SRP_PORT_REDIRECT if we get a port redirect REJ
                  * back, or SRP_DLID_REDIRECT if we get a lid/qp
                  * redirect REJ back.
                  */
                 switch (target->status) {
                 case 0:
                         return 0;
 
                 case SRP_PORT_REDIRECT:
                         ret = srp_lookup_path(target);
                         if (ret)
                                 return ret;
                         break;
 
                 case SRP_DLID_REDIRECT:
                         break;
 
                 case SRP_STALE_CONN:
                         /* Our current CM id was stale, and is now in timewait.
                          * Try to reconnect with a new one.
                          */
                         if (!retries-- || srp_new_cm_id(target)) {
                                 shost_printk(KERN_ERR, target->scsi_host, PFX
                                              "giving up on stale connection\n");
                                 target->status = -ECONNRESET;
                                 return target->status;
                         }
 
                         shost_printk(KERN_ERR, target->scsi_host, PFX
                                      "retrying stale connection\n");
                         break;
 
                 default:
                         return target->status;
                 }
         }
 }
 
 static void srp_unmap_data(struct scsi_cmnd *scmnd,
                            struct srp_target_port *target,
                            struct srp_request *req)
 {
         if (!scsi_sglist(scmnd) ||
             (scmnd->sc_data_direction != DMA_TO_DEVICE &&
              scmnd->sc_data_direction != DMA_FROM_DEVICE))
                 return;
 
         if (req->fmr) {
                 ib_fmr_pool_unmap(req->fmr);
                 req->fmr = NULL;
         }
 
         ib_dma_unmap_sg(target->srp_host->srp_dev->dev, scsi_sglist(scmnd),
                         scsi_sg_count(scmnd), scmnd->sc_data_direction);
 }
 
 static void srp_remove_req(struct srp_target_port *target, struct srp_request *req)
 {
         srp_unmap_data(req->scmnd, target, req);
         list_move_tail(&req->list, &target->free_reqs);
 }
 
 static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
 {
         req->scmnd->result = DID_RESET << 16;
         req->scmnd->scsi_done(req->scmnd);
         srp_remove_req(target, req);
 }
 
 static int srp_reconnect_target(struct srp_target_port *target)
 {
         struct ib_qp_attr qp_attr;
         struct srp_request *req, *tmp;
         struct ib_wc wc;
         int ret;
 
         spin_lock_irq(target->scsi_host->host_lock);
         if (target->state != SRP_TARGET_LIVE) {
                 spin_unlock_irq(target->scsi_host->host_lock);
                 return -EAGAIN;
         }
         target->state = SRP_TARGET_CONNECTING;
         spin_unlock_irq(target->scsi_host->host_lock);
 
         srp_disconnect_target(target);
         /*
          * Now get a new local CM ID so that we avoid confusing the
          * target in case things are really fouled up.
          */
         ret = srp_new_cm_id(target);
         if (ret)
                 goto err;
 
         qp_attr.qp_state = IB_QPS_RESET;
         ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
         if (ret)
                 goto err;
 
         ret = srp_init_qp(target, target->qp);
         if (ret)
                 goto err;
 
         while (ib_poll_cq(target->cq, 1, &wc) > 0)
                 ; /* nothing */
 
         spin_lock_irq(target->scsi_host->host_lock);
         list_for_each_entry_safe(req, tmp, &target->req_queue, list)
                 srp_reset_req(target, req);
         spin_unlock_irq(target->scsi_host->host_lock);
 
         target->rx_head         = 0;
         target->tx_head         = 0;
         target->tx_tail  = 0;
 
         target->qp_in_error = 0;
         ret = srp_connect_target(target);
         if (ret)
                 goto err;
 
         spin_lock_irq(target->scsi_host->host_lock);
         if (target->state == SRP_TARGET_CONNECTING) {
                 ret = 0;
                 target->state = SRP_TARGET_LIVE;
         } else
                 ret = -EAGAIN;
         spin_unlock_irq(target->scsi_host->host_lock);
 
         return ret;
 
 err:
         shost_printk(KERN_ERR, target->scsi_host,
                      PFX "reconnect failed (%d), removing target port.\n", ret);
 
         /*
          * We couldn't reconnect, so kill our target port off.
          * However, we have to defer the real removal because we might
          * be in the context of the SCSI error handler now, which
          * would deadlock if we call scsi_remove_host().
          */
         spin_lock_irq(target->scsi_host->host_lock);
         if (target->state == SRP_TARGET_CONNECTING) {
                 target->state = SRP_TARGET_DEAD;
                 INIT_WORK(&target->work, srp_remove_work);
                 schedule_work(&target->work);
         }
         spin_unlock_irq(target->scsi_host->host_lock);
 
         return ret;
 }
 
 static int srp_map_fmr(struct srp_target_port *target, struct scatterlist *scat,
                        int sg_cnt, struct srp_request *req,
                        struct srp_direct_buf *buf)
 {
         u64 io_addr = 0;
         u64 *dma_pages;
         u32 len;
         int page_cnt;
         int i, j;
         int ret;
         struct srp_device *dev = target->srp_host->srp_dev;
         struct ib_device *ibdev = dev->dev;
         struct scatterlist *sg;
 
         if (!dev->fmr_pool)
                 return -ENODEV;
 
         if (srp_target_is_mellanox(target) &&
             (ib_sg_dma_address(ibdev, &scat[0]) & ~dev->fmr_page_mask))
                 return -EINVAL;
 
         len = page_cnt = 0;
         scsi_for_each_sg(req->scmnd, sg, sg_cnt, i) {
                 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
 
                 if (ib_sg_dma_address(ibdev, sg) & ~dev->fmr_page_mask) {
                         if (i > 0)
                                 return -EINVAL;
                         else
                                 ++page_cnt;
                 }
                 if ((ib_sg_dma_address(ibdev, sg) + dma_len) &
                     ~dev->fmr_page_mask) {
                         if (i < sg_cnt - 1)
                                 return -EINVAL;
                         else
                                 ++page_cnt;
                 }
 
                 len += dma_len;
         }
 
         page_cnt += len >> dev->fmr_page_shift;
         if (page_cnt > SRP_FMR_SIZE)
                 return -ENOMEM;
 
         dma_pages = kmalloc(sizeof (u64) * page_cnt, GFP_ATOMIC);
         if (!dma_pages)
                 return -ENOMEM;
 
         page_cnt = 0;
         scsi_for_each_sg(req->scmnd, sg, sg_cnt, i) {
                 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
 
                 for (j = 0; j < dma_len; j += dev->fmr_page_size)
                         dma_pages[page_cnt++] =
                                 (ib_sg_dma_address(ibdev, sg) &
                                  dev->fmr_page_mask) + j;
         }
 
         req->fmr = ib_fmr_pool_map_phys(dev->fmr_pool,
                                         dma_pages, page_cnt, io_addr);
         if (IS_ERR(req->fmr)) {
                 ret = PTR_ERR(req->fmr);
                 req->fmr = NULL;
                 goto out;
         }
 
         buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, &scat[0]) &
                                ~dev->fmr_page_mask);
         buf->key = cpu_to_be32(req->fmr->fmr->rkey);
         buf->len = cpu_to_be32(len);
 
         ret = 0;
 
 out:
         kfree(dma_pages);
 
         return ret;
 }
 
 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
                         struct srp_request *req)
 {
         struct scatterlist *scat;
         struct srp_cmd *cmd = req->cmd->buf;
         int len, nents, count;
         u8 fmt = SRP_DATA_DESC_DIRECT;
         struct srp_device *dev;
         struct ib_device *ibdev;
 
         if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
                 return sizeof (struct srp_cmd);
 
         if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
             scmnd->sc_data_direction != DMA_TO_DEVICE) {
                 shost_printk(KERN_WARNING, target->scsi_host,
                              PFX "Unhandled data direction %d\n",
                              scmnd->sc_data_direction);
                 return -EINVAL;
         }
 
         nents = scsi_sg_count(scmnd);
         scat  = scsi_sglist(scmnd);
 
         dev = target->srp_host->srp_dev;
         ibdev = dev->dev;
 
         count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
 
         fmt = SRP_DATA_DESC_DIRECT;
         len = sizeof (struct srp_cmd) +        sizeof (struct srp_direct_buf);
 
         if (count == 1) {
                 /*
                  * The midlayer only generated a single gather/scatter
                  * entry, or DMA mapping coalesced everything to a
                  * single entry.  So a direct descriptor along with
                  * the DMA MR suffices.
                  */
                 struct srp_direct_buf *buf = (void *) cmd->add_data;
 
                 buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
                 buf->key = cpu_to_be32(dev->mr->rkey);
                 buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
         } else if (srp_map_fmr(target, scat, count, req,
                                (void *) cmd->add_data)) {
                 /*
                  * FMR mapping failed, and the scatterlist has more
                  * than one entry.  Generate an indirect memory
                  * descriptor.
                  */
                 struct srp_indirect_buf *buf = (void *) cmd->add_data;
                 struct scatterlist *sg;
                 u32 datalen = 0;
                 int i;
 
                 fmt = SRP_DATA_DESC_INDIRECT;
                 len = sizeof (struct srp_cmd) +
                         sizeof (struct srp_indirect_buf) +
                         count * sizeof (struct srp_direct_buf);
 
                 scsi_for_each_sg(scmnd, sg, count, i) {
                         unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
 
                         buf->desc_list[i].va  =
                                 cpu_to_be64(ib_sg_dma_address(ibdev, sg));
                         buf->desc_list[i].key =
                                 cpu_to_be32(dev->mr->rkey);
                         buf->desc_list[i].len = cpu_to_be32(dma_len);
                         datalen += dma_len;
                 }
 
                 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
                         cmd->data_out_desc_cnt = count;
                 else
                         cmd->data_in_desc_cnt = count;
 
                 buf->table_desc.va  =
                         cpu_to_be64(req->cmd->dma + sizeof *cmd + sizeof *buf);
                 buf->table_desc.key =
                         cpu_to_be32(target->srp_host->srp_dev->mr->rkey);
                 buf->table_desc.len =
                         cpu_to_be32(count * sizeof (struct srp_direct_buf));
 
                 buf->len = cpu_to_be32(datalen);
         }
 
         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
                 cmd->buf_fmt = fmt << 4;
         else
                 cmd->buf_fmt = fmt;
 
         return len;
 }
 
 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
 {
         struct srp_request *req;
         struct scsi_cmnd *scmnd;
         unsigned long flags;
         s32 delta;
 
         delta = (s32) be32_to_cpu(rsp->req_lim_delta);
 
         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 
         target->req_lim += delta;
 
         req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
 
         if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
                 if (be32_to_cpu(rsp->resp_data_len) < 4)
                         req->tsk_status = -1;
                 else
                         req->tsk_status = rsp->data[3];
                 complete(&req->done);
         } else {
                 scmnd = req->scmnd;
                 if (!scmnd)
                         shost_printk(KERN_ERR, target->scsi_host,
                                      "Null scmnd for RSP w/tag %016llx\n",
                                      (unsigned long long) rsp->tag);
                 scmnd->result = rsp->status;
 
                 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
                         memcpy(scmnd->sense_buffer, rsp->data +
                                be32_to_cpu(rsp->resp_data_len),
                                min_t(int, be32_to_cpu(rsp->sense_data_len),
                                      SCSI_SENSE_BUFFERSIZE));
                 }
 
                 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
                         scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
                 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
                         scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
 
                 if (!req->tsk_mgmt) {
                         scmnd->host_scribble = (void *) -1L;
                         scmnd->scsi_done(scmnd);
 
                         srp_remove_req(target, req);
                 } else
                         req->cmd_done = 1;
         }
 
         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 }
 
 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
 {
         struct ib_device *dev;
         struct srp_iu *iu;
         u8 opcode;
 
         iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
 
         dev = target->srp_host->srp_dev->dev;
         ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_ti_iu_len,
                                    DMA_FROM_DEVICE);
 
         opcode = *(u8 *) iu->buf;
 
         if (0) {
                 int i;
 
                 shost_printk(KERN_ERR, target->scsi_host,
                              PFX "recv completion, opcode 0x%02x\n", opcode);
 
                 for (i = 0; i < wc->byte_len; ++i) {
                         if (i % 8 == 0)
                                 printk(KERN_ERR "  [%02x] ", i);
                         printk(" %02x", ((u8 *) iu->buf)[i]);
                         if ((i + 1) % 8 == 0)
                                 printk("\n");
                 }
 
                 if (wc->byte_len % 8)
                         printk("\n");
         }
 
         switch (opcode) {
         case SRP_RSP:
                 srp_process_rsp(target, iu->buf);
                 break;
 
         case SRP_T_LOGOUT:
                 /* XXX Handle target logout */
                 shost_printk(KERN_WARNING, target->scsi_host,
                              PFX "Got target logout request\n");
                 break;
 
         default:
                 shost_printk(KERN_WARNING, target->scsi_host,
                              PFX "Unhandled SRP opcode 0x%02x\n", opcode);
                 break;
         }
 
         ib_dma_sync_single_for_device(dev, iu->dma, target->max_ti_iu_len,
                                       DMA_FROM_DEVICE);
 }
 
 static void srp_completion(struct ib_cq *cq, void *target_ptr)
 {
         struct srp_target_port *target = target_ptr;
         struct ib_wc wc;
 
         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
         while (ib_poll_cq(cq, 1, &wc) > 0) {
                 if (wc.status) {
                         shost_printk(KERN_ERR, target->scsi_host,
                                      PFX "failed %s status %d\n",
                                      wc.wr_id & SRP_OP_RECV ? "receive" : "send",
                                      wc.status);
                         target->qp_in_error = 1;
                         break;
                 }
 
                 if (wc.wr_id & SRP_OP_RECV)
                         srp_handle_recv(target, &wc);
                 else
                         ++target->tx_tail;
         }
 }
 
 static int __srp_post_recv(struct srp_target_port *target)
 {
         struct srp_iu *iu;
         struct ib_sge list;
         struct ib_recv_wr wr, *bad_wr;
         unsigned int next;
         int ret;
 
         next          = target->rx_head & (SRP_RQ_SIZE - 1);
         wr.wr_id = next | SRP_OP_RECV;
         iu          = target->rx_ring[next];
 
         list.addr   = iu->dma;
         list.length = iu->size;
         list.lkey   = target->srp_host->srp_dev->mr->lkey;
 
         wr.next     = NULL;
         wr.sg_list  = &list;
         wr.num_sge  = 1;
 
         ret = ib_post_recv(target->qp, &wr, &bad_wr);
         if (!ret)
                 ++target->rx_head;
 
         return ret;
 }
 
 static int srp_post_recv(struct srp_target_port *target)
 {
         unsigned long flags;
         int ret;
 
         spin_lock_irqsave(target->scsi_host->host_lock, flags);
         ret = __srp_post_recv(target);
         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 
         return ret;
 }
 
 /*
  * Must be called with target->scsi_host->host_lock held to protect
  * req_lim and tx_head.  Lock cannot be dropped between call here and
  * call to __srp_post_send().
  */
 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
                                         enum srp_request_type req_type)
 {
         s32 min = (req_type == SRP_REQ_TASK_MGMT) ? 1 : 2;
 
         if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
                 return NULL;
 
         if (target->req_lim < min) {
                 ++target->zero_req_lim;
                 return NULL;
         }
 
         return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
 }
 
 /*
  * Must be called with target->scsi_host->host_lock held to protect
  * req_lim and tx_head.
  */
 static int __srp_post_send(struct srp_target_port *target,
                            struct srp_iu *iu, int len)
 {
         struct ib_sge list;
         struct ib_send_wr wr, *bad_wr;
         int ret = 0;
 
         list.addr   = iu->dma;
         list.length = len;
         list.lkey   = target->srp_host->srp_dev->mr->lkey;
 
         wr.next       = NULL;
        wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
        wr.sg_list    = &list;
        wr.num_sge    = 1;
        wr.opcode     = IB_WR_SEND;
        wr.send_flags = IB_SEND_SIGNALED;

        ret = ib_post_send(target->qp, &wr, &bad_wr);

        if (!ret) {
                ++target->tx_head;
                --target->req_lim;
        }

        return ret;
}

static int srp_queuecommand(struct scsi_cmnd *scmnd,
                            void (*done)(struct scsi_cmnd *))
{
        struct srp_target_port *target = host_to_target(scmnd->device->host);
        struct srp_request *req;
        struct srp_iu *iu;
        struct srp_cmd *cmd;
        struct ib_device *dev;
        int len;

        if (target->state == SRP_TARGET_CONNECTING)
                goto err;

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED) {
                scmnd->result = DID_BAD_TARGET << 16;
                done(scmnd);
                return 0;
        }

        iu = __srp_get_tx_iu(target, SRP_REQ_NORMAL);
        if (!iu)
                goto err;

        dev = target->srp_host->srp_dev->dev;
        ib_dma_sync_single_for_cpu(dev, iu->dma, srp_max_iu_len,
                                   DMA_TO_DEVICE);

        req = list_entry(target->free_reqs.next, struct srp_request, list);

        scmnd->scsi_done     = done;
        scmnd->result        = 0;
        scmnd->host_scribble = (void *) (long) req->index;

        cmd = iu->buf;
        memset(cmd, 0, sizeof *cmd);

        cmd->opcode = SRP_CMD;
        cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
        cmd->tag    = req->index;
        memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);

        req->scmnd    = scmnd;
        req->cmd      = iu;
        req->cmd_done = 0;
        req->tsk_mgmt = NULL;

        len = srp_map_data(scmnd, target, req);
        if (len < 0) {
                shost_printk(KERN_ERR, target->scsi_host,
                             PFX "Failed to map data\n");
                goto err;
        }

        if (__srp_post_recv(target)) {
                shost_printk(KERN_ERR, target->scsi_host, PFX "Recv failed\n");
                goto err_unmap;
        }

        ib_dma_sync_single_for_device(dev, iu->dma, srp_max_iu_len,
                                      DMA_TO_DEVICE);

        if (__srp_post_send(target, iu, len)) {
                shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
                goto err_unmap;
        }

        list_move_tail(&req->list, &target->req_queue);

        return 0;

err_unmap:
        srp_unmap_data(scmnd, target, req);

err:
        return SCSI_MLQUEUE_HOST_BUSY;
}

static int srp_alloc_iu_bufs(struct srp_target_port *target)
{
        int i;

        for (i = 0; i < SRP_RQ_SIZE; ++i) {
                target->rx_ring[i] = srp_alloc_iu(target->srp_host,
                                                  target->max_ti_iu_len,
                                                  GFP_KERNEL, DMA_FROM_DEVICE);
                if (!target->rx_ring[i])
                        goto err;
        }

        for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
                target->tx_ring[i] = srp_alloc_iu(target->srp_host,
                                                  srp_max_iu_len,
                                                  GFP_KERNEL, DMA_TO_DEVICE);
                if (!target->tx_ring[i])
                        goto err;
        }

        return 0;

err:
        for (i = 0; i < SRP_RQ_SIZE; ++i) {
                srp_free_iu(target->srp_host, target->rx_ring[i]);
                target->rx_ring[i] = NULL;
        }

        for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
                srp_free_iu(target->srp_host, target->tx_ring[i]);
                target->tx_ring[i] = NULL;
        }

        return -ENOMEM;
}

static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
                               struct ib_cm_event *event,
                               struct srp_target_port *target)
{
        struct Scsi_Host *shost = target->scsi_host;
        struct ib_class_port_info *cpi;
        int opcode;

        switch (event->param.rej_rcvd.reason) {
        case IB_CM_REJ_PORT_CM_REDIRECT:
                cpi = event->param.rej_rcvd.ari;
                target->path.dlid = cpi->redirect_lid;
                target->path.pkey = cpi->redirect_pkey;
                cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
                memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);

                target->status = target->path.dlid ?
                        SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
                break;

        case IB_CM_REJ_PORT_REDIRECT:
                if (srp_target_is_topspin(target)) {
                        /*
                         * Topspin/Cisco SRP gateways incorrectly send
                         * reject reason code 25 when they mean 24
                         * (port redirect).
                         */
                        memcpy(target->path.dgid.raw,
                               event->param.rej_rcvd.ari, 16);

                        shost_printk(KERN_DEBUG, shost,
                                     PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
                                     (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
                                     (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));

                        target->status = SRP_PORT_REDIRECT;
                } else {
                        shost_printk(KERN_WARNING, shost,
                                     "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
                        target->status = -ECONNRESET;
                }
                break;

        case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
                shost_printk(KERN_WARNING, shost,
                            "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
                target->status = -ECONNRESET;
                break;

        case IB_CM_REJ_CONSUMER_DEFINED:
                opcode = *(u8 *) event->private_data;
                if (opcode == SRP_LOGIN_REJ) {
                        struct srp_login_rej *rej = event->private_data;
                        u32 reason = be32_to_cpu(rej->reason);

                        if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
                                shost_printk(KERN_WARNING, shost,
                                             PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
                        else
                                shost_printk(KERN_WARNING, shost,
                                            PFX "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
                } else
                        shost_printk(KERN_WARNING, shost,
                                     "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
                                     " opcode 0x%02x\n", opcode);
                target->status = -ECONNRESET;
                break;

        case IB_CM_REJ_STALE_CONN:
                shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
                target->status = SRP_STALE_CONN;
                break;

        default:
                shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
                             event->param.rej_rcvd.reason);
                target->status = -ECONNRESET;
        }
}

static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
{
        struct srp_target_port *target = cm_id->context;
        struct ib_qp_attr *qp_attr = NULL;
        int attr_mask = 0;
        int comp = 0;
        int opcode = 0;

        switch (event->event) {
        case IB_CM_REQ_ERROR:
                shost_printk(KERN_DEBUG, target->scsi_host,
                             PFX "Sending CM REQ failed\n");
                comp = 1;
                target->status = -ECONNRESET;
                break;

        case IB_CM_REP_RECEIVED:
                comp = 1;
                opcode = *(u8 *) event->private_data;

                if (opcode == SRP_LOGIN_RSP) {
                        struct srp_login_rsp *rsp = event->private_data;

                        target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
                        target->req_lim       = be32_to_cpu(rsp->req_lim_delta);

                        target->scsi_host->can_queue = min(target->req_lim,
                                                           target->scsi_host->can_queue);
                } else {
                        shost_printk(KERN_WARNING, target->scsi_host,
                                    PFX "Unhandled RSP opcode %#x\n", opcode);
                        target->status = -ECONNRESET;
                        break;
                }

                if (!target->rx_ring[0]) {
                        target->status = srp_alloc_iu_bufs(target);
                        if (target->status)
                                break;
                }

                qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
                if (!qp_attr) {
                        target->status = -ENOMEM;
                        break;
                }

                qp_attr->qp_state = IB_QPS_RTR;
                target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
                if (target->status)
                        break;

                target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
                if (target->status)
                        break;

                target->status = srp_post_recv(target);
                if (target->status)
                        break;

                qp_attr->qp_state = IB_QPS_RTS;
                target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
                if (target->status)
                        break;

                target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
                if (target->status)
                        break;

                target->status = ib_send_cm_rtu(cm_id, NULL, 0);
                if (target->status)
                        break;

                break;

        case IB_CM_REJ_RECEIVED:
                shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
                comp = 1;

                srp_cm_rej_handler(cm_id, event, target);
                break;

        case IB_CM_DREQ_RECEIVED:
                shost_printk(KERN_WARNING, target->scsi_host,
                             PFX "DREQ received - connection closed\n");
                if (ib_send_cm_drep(cm_id, NULL, 0))
                        shost_printk(KERN_ERR, target->scsi_host,
                                     PFX "Sending CM DREP failed\n");
                break;

        case IB_CM_TIMEWAIT_EXIT:
                shost_printk(KERN_ERR, target->scsi_host,
                             PFX "connection closed\n");

                comp = 1;
                target->status = 0;
                break;

        case IB_CM_MRA_RECEIVED:
        case IB_CM_DREQ_ERROR:
        case IB_CM_DREP_RECEIVED:
                break;

        default:
                shost_printk(KERN_WARNING, target->scsi_host,
                             PFX "Unhandled CM event %d\n", event->event);
                break;
        }

        if (comp)
                complete(&target->done);

        kfree(qp_attr);

        return 0;
}

static int srp_send_tsk_mgmt(struct srp_target_port *target,
                             struct srp_request *req, u8 func)
{
        struct srp_iu *iu;
        struct srp_tsk_mgmt *tsk_mgmt;

        spin_lock_irq(target->scsi_host->host_lock);

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED) {
                req->scmnd->result = DID_BAD_TARGET << 16;
                goto out;
        }

        init_completion(&req->done);

        iu = __srp_get_tx_iu(target, SRP_REQ_TASK_MGMT);
        if (!iu)
                goto out;

        tsk_mgmt = iu->buf;
        memset(tsk_mgmt, 0, sizeof *tsk_mgmt);

        tsk_mgmt->opcode         = SRP_TSK_MGMT;
        tsk_mgmt->lun                 = cpu_to_be64((u64) req->scmnd->device->lun << 48);
        tsk_mgmt->tag                 = req->index | SRP_TAG_TSK_MGMT;
        tsk_mgmt->tsk_mgmt_func = func;
        tsk_mgmt->task_tag         = req->index;

        if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
                goto out;

        req->tsk_mgmt = iu;

        spin_unlock_irq(target->scsi_host->host_lock);

        if (!wait_for_completion_timeout(&req->done,
                                         msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
                return -1;

        return 0;

out:
        spin_unlock_irq(target->scsi_host->host_lock);
        return -1;
}

static int srp_find_req(struct srp_target_port *target,
                        struct scsi_cmnd *scmnd,
                        struct srp_request **req)
{
        if (scmnd->host_scribble == (void *) -1L)
                return -1;

        *req = &target->req_ring[(long) scmnd->host_scribble];

        return 0;
}

static int srp_abort(struct scsi_cmnd *scmnd)
{
        struct srp_target_port *target = host_to_target(scmnd->device->host);
        struct srp_request *req;
        int ret = SUCCESS;

        shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");

        if (target->qp_in_error)
                return FAILED;
        if (srp_find_req(target, scmnd, &req))
                return FAILED;
        if (srp_send_tsk_mgmt(target, req, SRP_TSK_ABORT_TASK))
                return FAILED;

        spin_lock_irq(target->scsi_host->host_lock);

        if (req->cmd_done) {
                srp_remove_req(target, req);
                scmnd->scsi_done(scmnd);
        } else if (!req->tsk_status) {
                srp_remove_req(target, req);
                scmnd->result = DID_ABORT << 16;
        } else
                ret = FAILED;

        spin_unlock_irq(target->scsi_host->host_lock);

        return ret;
}

static int srp_reset_device(struct scsi_cmnd *scmnd)
{
        struct srp_target_port *target = host_to_target(scmnd->device->host);
        struct srp_request *req, *tmp;

        shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");

        if (target->qp_in_error)
                return FAILED;
        if (srp_find_req(target, scmnd, &req))
                return FAILED;
        if (srp_send_tsk_mgmt(target, req, SRP_TSK_LUN_RESET))
                return FAILED;
        if (req->tsk_status)
                return FAILED;

        spin_lock_irq(target->scsi_host->host_lock);

        list_for_each_entry_safe(req, tmp, &target->req_queue, list)
                if (req->scmnd->device == scmnd->device)
                        srp_reset_req(target, req);

        spin_unlock_irq(target->scsi_host->host_lock);

        return SUCCESS;
}

static int srp_reset_host(struct scsi_cmnd *scmnd)
{
        struct srp_target_port *target = host_to_target(scmnd->device->host);
        int ret = FAILED;

        shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");

        if (!srp_reconnect_target(target))
                ret = SUCCESS;

        return ret;
}

static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
                           char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED)
                return -ENODEV;

        return sprintf(buf, "0x%016llx\n",
                       (unsigned long long) be64_to_cpu(target->id_ext));
}

static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
                             char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED)
                return -ENODEV;

        return sprintf(buf, "0x%016llx\n",
                       (unsigned long long) be64_to_cpu(target->ioc_guid));
}

static ssize_t show_service_id(struct device *dev,
                               struct device_attribute *attr, char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED)
                return -ENODEV;

        return sprintf(buf, "0x%016llx\n",
                       (unsigned long long) be64_to_cpu(target->service_id));
}

static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
                         char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED)
                return -ENODEV;

        return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
}

static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
                         char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED)
                return -ENODEV;

        return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
                       be16_to_cpu(((__be16 *) target->path.dgid.raw)[0]),
                       be16_to_cpu(((__be16 *) target->path.dgid.raw)[1]),
                       be16_to_cpu(((__be16 *) target->path.dgid.raw)[2]),
                       be16_to_cpu(((__be16 *) target->path.dgid.raw)[3]),
                       be16_to_cpu(((__be16 *) target->path.dgid.raw)[4]),
                       be16_to_cpu(((__be16 *) target->path.dgid.raw)[5]),
                       be16_to_cpu(((__be16 *) target->path.dgid.raw)[6]),
                       be16_to_cpu(((__be16 *) target->path.dgid.raw)[7]));
}

static ssize_t show_orig_dgid(struct device *dev,
                              struct device_attribute *attr, char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED)
                return -ENODEV;

        return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
                       be16_to_cpu(target->orig_dgid[0]),
                       be16_to_cpu(target->orig_dgid[1]),
                       be16_to_cpu(target->orig_dgid[2]),
                       be16_to_cpu(target->orig_dgid[3]),
                       be16_to_cpu(target->orig_dgid[4]),
                       be16_to_cpu(target->orig_dgid[5]),
                       be16_to_cpu(target->orig_dgid[6]),
                       be16_to_cpu(target->orig_dgid[7]));
}

static ssize_t show_zero_req_lim(struct device *dev,
                                 struct device_attribute *attr, char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        if (target->state == SRP_TARGET_DEAD ||
            target->state == SRP_TARGET_REMOVED)
                return -ENODEV;

        return sprintf(buf, "%d\n", target->zero_req_lim);
}

static ssize_t show_local_ib_port(struct device *dev,
                                  struct device_attribute *attr, char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        return sprintf(buf, "%d\n", target->srp_host->port);
}

static ssize_t show_local_ib_device(struct device *dev,
                                    struct device_attribute *attr, char *buf)
{
        struct srp_target_port *target = host_to_target(class_to_shost(dev));

        return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
}

static DEVICE_ATTR(id_ext,            S_IRUGO, show_id_ext,           NULL);
static DEVICE_ATTR(ioc_guid,            S_IRUGO, show_ioc_guid,           NULL);
static DEVICE_ATTR(service_id,            S_IRUGO, show_service_id,           NULL);
static DEVICE_ATTR(pkey,            S_IRUGO, show_pkey,                   NULL);
static DEVICE_ATTR(dgid,            S_IRUGO, show_dgid,                   NULL);
static DEVICE_ATTR(orig_dgid,            S_IRUGO, show_orig_dgid,           NULL);
static DEVICE_ATTR(zero_req_lim,    S_IRUGO, show_zero_req_lim,           NULL);
static DEVICE_ATTR(local_ib_port,   S_IRUGO, show_local_ib_port,   NULL);
static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);

static struct device_attribute *srp_host_attrs[] = {
        &dev_attr_id_ext,
        &dev_attr_ioc_guid,
        &dev_attr_service_id,
        &dev_attr_pkey,
        &dev_attr_dgid,
        &dev_attr_orig_dgid,
        &dev_attr_zero_req_lim,
        &dev_attr_local_ib_port,
        &dev_attr_local_ib_device,
        NULL
};

static struct scsi_host_template srp_template = {
        .module                                = THIS_MODULE,
        .name                                = "InfiniBand SRP initiator",
        .proc_name                        = DRV_NAME,
        .info                                = srp_target_info,
        .queuecommand                        = srp_queuecommand,
        .eh_abort_handler                = srp_abort,
        .eh_device_reset_handler        = srp_reset_device,
        .eh_host_reset_handler                = srp_reset_host,
        .can_queue                        = SRP_SQ_SIZE,
        .this_id                        = -1,
        .cmd_per_lun                        = SRP_SQ_SIZE,
        .use_clustering                        = ENABLE_CLUSTERING,
        .shost_attrs                        = srp_host_attrs
};

static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
{
        struct srp_rport_identifiers ids;
        struct srp_rport *rport;

        sprintf(target->target_name, "SRP.T10:%016llX",
                 (unsigned long long) be64_to_cpu(target->id_ext));

        if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
                return -ENODEV;

        memcpy(ids.port_id, &target->id_ext, 8);
        memcpy(ids.port_id + 8, &target->ioc_guid, 8);
        ids.roles = SRP_RPORT_ROLE_TARGET;
        rport = srp_rport_add(target->scsi_host, &ids);
        if (IS_ERR(rport)) {
                scsi_remove_host(target->scsi_host);
                return PTR_ERR(rport);
        }

        spin_lock(&host->target_lock);
        list_add_tail(&target->list, &host->target_list);
        spin_unlock(&host->target_lock);

        target->state = SRP_TARGET_LIVE;

        scsi_scan_target(&target->scsi_host->shost_gendev,
                         0, target->scsi_id, SCAN_WILD_CARD, 0);

        return 0;
}

static void srp_release_dev(struct device *dev)
{
        struct srp_host *host =
                container_of(dev, struct srp_host, dev);

        complete(&host->released);
}

static struct class srp_class = {
        .name    = "infiniband_srp",
        .dev_release = srp_release_dev
};

/*
 * Target ports are added by writing
 *
 *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
 *     pkey=<P_Key>,service_id=<service ID>
 *
 * to the add_target sysfs attribute.
 */
enum {
        SRP_OPT_ERR                = 0,
        SRP_OPT_ID_EXT                = 1 << 0,
        SRP_OPT_IOC_GUID        = 1 << 1,
        SRP_OPT_DGID                = 1 << 2,
        SRP_OPT_PKEY                = 1 << 3,
        SRP_OPT_SERVICE_ID        = 1 << 4,
        SRP_OPT_MAX_SECT        = 1 << 5,
        SRP_OPT_MAX_CMD_PER_LUN        = 1 << 6,
        SRP_OPT_IO_CLASS        = 1 << 7,
        SRP_OPT_INITIATOR_EXT        = 1 << 8,
        SRP_OPT_ALL                = (SRP_OPT_ID_EXT        |
                                   SRP_OPT_IOC_GUID        |
                                   SRP_OPT_DGID                |
                                   SRP_OPT_PKEY                |
                                   SRP_OPT_SERVICE_ID),
};

static const match_table_t srp_opt_tokens = {
        { SRP_OPT_ID_EXT,                "id_ext=%s"                 },
        { SRP_OPT_IOC_GUID,                "ioc_guid=%s"                 },
        { SRP_OPT_DGID,                        "dgid=%s"                 },
        { SRP_OPT_PKEY,                        "pkey=%x"                 },
        { SRP_OPT_SERVICE_ID,                "service_id=%s"                },
        { SRP_OPT_MAX_SECT,                "max_sect=%d"                 },
        { SRP_OPT_MAX_CMD_PER_LUN,        "max_cmd_per_lun=%d"         },
        { SRP_OPT_IO_CLASS,                "io_class=%x"                },
        { SRP_OPT_INITIATOR_EXT,        "initiator_ext=%s"        },
        { SRP_OPT_ERR,                        NULL                         }
};

static int srp_parse_options(const char *buf, struct srp_target_port *target)
{
        char *options, *sep_opt;
        char *p;
        char dgid[3];
        substring_t args[MAX_OPT_ARGS];
        int opt_mask = 0;
        int token;
        int ret = -EINVAL;
        int i;

        options = kstrdup(buf, GFP_KERNEL);
        if (!options)
                return -ENOMEM;

        sep_opt = options;
        while ((p = strsep(&sep_opt, ",")) != NULL) {
                if (!*p)
                        continue;

                token = match_token(p, srp_opt_tokens, args);
                opt_mask |= token;

                switch (token) {
                case SRP_OPT_ID_EXT:
                        p = match_strdup(args);
                        if (!p) {
                                ret = -ENOMEM;
                                goto out;
                        }
                        target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
                        kfree(p);
                        break;

                case SRP_OPT_IOC_GUID:
                        p = match_strdup(args);
                        if (!p) {
                                ret = -ENOMEM;
                                goto out;
                        }
                        target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
                        kfree(p);
                        break;

                case SRP_OPT_DGID:
                        p = match_strdup(args);
                        if (!p) {
                                ret = -ENOMEM;
                                goto out;
                        }
                        if (strlen(p) != 32) {
                                printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
                                kfree(p);
                                goto out;
                        }

                        for (i = 0; i < 16; ++i) {
                                strlcpy(dgid, p + i * 2, 3);
                                target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
                        }
                        kfree(p);
                        memcpy(target->orig_dgid, target->path.dgid.raw, 16);
                        break;

                case SRP_OPT_PKEY:
                        if (match_hex(args, &token)) {
                                printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
                                goto out;
                        }
                        target->path.pkey = cpu_to_be16(token);
                        break;

                case SRP_OPT_SERVICE_ID:
                        p = match_strdup(args);
                        if (!p) {
                                ret = -ENOMEM;
                                goto out;
                        }
                        target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
                        target->path.service_id = target->service_id;
                        kfree(p);
                        break;

                case SRP_OPT_MAX_SECT:
                        if (match_int(args, &token)) {
                                printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
                                goto out;
                        }
                        target->scsi_host->max_sectors = token;
                        break;

                case SRP_OPT_MAX_CMD_PER_LUN:
                        if (match_int(args, &token)) {
                                printk(KERN_WARNING PFX "bad max cmd_per_lun parameter '%s'\n", p);
                                goto out;
                        }
                        target->scsi_host->cmd_per_lun = min(token, SRP_SQ_SIZE);
                        break;

                case SRP_OPT_IO_CLASS:
                        if (match_hex(args, &token)) {
                                printk(KERN_WARNING PFX "bad  IO class parameter '%s' \n", p);
                                goto out;
                        }
                        if (token != SRP_REV10_IB_IO_CLASS &&
                            token != SRP_REV16A_IB_IO_CLASS) {
                                printk(KERN_WARNING PFX "unknown IO class parameter value"
                                       " %x specified (use %x or %x).\n",
                                       token, SRP_REV10_IB_IO_CLASS, SRP_REV16A_IB_IO_CLASS);
                                goto out;
                        }
                        target->io_class = token;
                        break;

                case SRP_OPT_INITIATOR_EXT:
                        p = match_strdup(args);
                        if (!p) {
                                ret = -ENOMEM;
                                goto out;
                        }
                        target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
                        kfree(p);
                        break;

                default:
                        printk(KERN_WARNING PFX "unknown parameter or missing value "
                               "'%s' in target creation request\n", p);
                        goto out;
                }
        }

        if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
                ret = 0;
        else
                for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
                        if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
                            !(srp_opt_tokens[i].token & opt_mask))
                                printk(KERN_WARNING PFX "target creation request is "
                                       "missing parameter '%s'\n",
                                       srp_opt_tokens[i].pattern);

out:
        kfree(options);
        return ret;
}

static ssize_t srp_create_target(struct device *dev,
                                 struct device_attribute *attr,
                                 const char *buf, size_t count)
{
        struct srp_host *host =
                container_of(dev, struct srp_host, dev);
        struct Scsi_Host *target_host;
        struct srp_target_port *target;
        int ret;
        int i;

        target_host = scsi_host_alloc(&srp_template,
                                      sizeof (struct srp_target_port));
        if (!target_host)
                return -ENOMEM;

        target_host->transportt = ib_srp_transport_template;
        target_host->max_lun     = SRP_MAX_LUN;
        target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;

        target = host_to_target(target_host);

        target->io_class   = SRP_REV16A_IB_IO_CLASS;
        target->scsi_host  = target_host;
        target->srp_host   = host;

        INIT_LIST_HEAD(&target->free_reqs);
        INIT_LIST_HEAD(&target->req_queue);
        for (i = 0; i < SRP_SQ_SIZE; ++i) {
                target->req_ring[i].index = i;
                list_add_tail(&target->req_ring[i].list, &target->free_reqs);
        }

        ret = srp_parse_options(buf, target);
        if (ret)
                goto err;

        ib_query_gid(host->srp_dev->dev, host->port, 0, &target->path.sgid);

        shost_printk(KERN_DEBUG, target->scsi_host, PFX
                     "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
                     "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
               (unsigned long long) be64_to_cpu(target->id_ext),
               (unsigned long long) be64_to_cpu(target->ioc_guid),
               be16_to_cpu(target->path.pkey),
               (unsigned long long) be64_to_cpu(target->service_id),
               (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[0]),
               (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[2]),
               (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[4]),
               (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[6]),
               (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[8]),
               (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[10]),
               (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[12]),
               (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[14]));

        ret = srp_create_target_ib(target);
        if (ret)
                goto err;

        ret = srp_new_cm_id(target);
        if (ret)
                goto err_free;

        target->qp_in_error = 0;
        ret = srp_connect_target(target);
        if (ret) {
                shost_printk(KERN_ERR, target->scsi_host,
                             PFX "Connection failed\n");
                goto err_cm_id;
        }

        ret = srp_add_target(host, target);
        if (ret)
                goto err_disconnect;

        return count;

err_disconnect:
        srp_disconnect_target(target);

err_cm_id:
        ib_destroy_cm_id(target->cm_id);

err_free:
        srp_free_target_ib(target);

err:
        scsi_host_put(target_host);

        return ret;
}

static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);

static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
                          char *buf)
{
        struct srp_host *host = container_of(dev, struct srp_host, dev);

        return sprintf(buf, "%s\n", host->srp_dev->dev->name);
}

static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);

static ssize_t show_port(struct device *dev, struct device_attribute *attr,
                         char *buf)
{
        struct srp_host *host = container_of(dev, struct srp_host, dev);

        return sprintf(buf, "%d\n", host->port);
}

static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);

static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
{
        struct srp_host *host;

        host = kzalloc(sizeof *host, GFP_KERNEL);
        if (!host)
                return NULL;

        INIT_LIST_HEAD(&host->target_list);
        spin_lock_init(&host->target_lock);
        init_completion(&host->released);
        host->srp_dev = device;
        host->port = port;

        host->dev.class = &srp_class;
        host->dev.parent = device->dev->dma_device;
        snprintf(host->dev.bus_id, BUS_ID_SIZE, "srp-%s-%d",
                 device->dev->name, port);

        if (device_register(&host->dev))
                goto free_host;
        if (device_create_file(&host->dev, &dev_attr_add_target))
                goto err_class;
        if (device_create_file(&host->dev, &dev_attr_ibdev))
                goto err_class;
        if (device_create_file(&host->dev, &dev_attr_port))
                goto err_class;

        return host;

err_class:
        device_unregister(&host->dev);

free_host:
        kfree(host);

        return NULL;
}

static void srp_add_one(struct ib_device *device)
{
        struct srp_device *srp_dev;
        struct ib_device_attr *dev_attr;
        struct ib_fmr_pool_param fmr_param;
        struct srp_host *host;
        int s, e, p;

        dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
        if (!dev_attr)
                return;

        if (ib_query_device(device, dev_attr)) {
                printk(KERN_WARNING PFX "Query device failed for %s\n",
                       device->name);
                goto free_attr;
        }

        srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
        if (!srp_dev)
                goto free_attr;

        /*
         * Use the smallest page size supported by the HCA, down to a
         * minimum of 512 bytes (which is the smallest sector that a
         * SCSI command will ever carry).
         */
        srp_dev->fmr_page_shift = max(9, ffs(dev_attr->page_size_cap) - 1);
        srp_dev->fmr_page_size  = 1 << srp_dev->fmr_page_shift;
        srp_dev->fmr_page_mask  = ~((u64) srp_dev->fmr_page_size - 1);

        INIT_LIST_HEAD(&srp_dev->dev_list);

        srp_dev->dev = device;
        srp_dev->pd  = ib_alloc_pd(device);
        if (IS_ERR(srp_dev->pd))
                goto free_dev;

        srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
                                    IB_ACCESS_LOCAL_WRITE |
                                    IB_ACCESS_REMOTE_READ |
                                    IB_ACCESS_REMOTE_WRITE);
        if (IS_ERR(srp_dev->mr))
                goto err_pd;

        memset(&fmr_param, 0, sizeof fmr_param);
        fmr_param.pool_size            = SRP_FMR_POOL_SIZE;
        fmr_param.dirty_watermark   = SRP_FMR_DIRTY_SIZE;
        fmr_param.cache                    = 1;
        fmr_param.max_pages_per_fmr = SRP_FMR_SIZE;
        fmr_param.page_shift            = srp_dev->fmr_page_shift;
        fmr_param.access            = (IB_ACCESS_LOCAL_WRITE |
                                       IB_ACCESS_REMOTE_WRITE |
                                       IB_ACCESS_REMOTE_READ);

        srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
        if (IS_ERR(srp_dev->fmr_pool))
                srp_dev->fmr_pool = NULL;

        if (device->node_type == RDMA_NODE_IB_SWITCH) {
                s = 0;
                e = 0;
        } else {
                s = 1;
                e = device->phys_port_cnt;
        }

        for (p = s; p <= e; ++p) {
                host = srp_add_port(srp_dev, p);
                if (host)
                        list_add_tail(&host->list, &srp_dev->dev_list);
        }

        ib_set_client_data(device, &srp_client, srp_dev);

        goto free_attr;

err_pd:
        ib_dealloc_pd(srp_dev->pd);

free_dev:
        kfree(srp_dev);

free_attr:
        kfree(dev_attr);
}

static void srp_remove_one(struct ib_device *device)
{
        struct srp_device *srp_dev;
        struct srp_host *host, *tmp_host;
        LIST_HEAD(target_list);
        struct srp_target_port *target, *tmp_target;

        srp_dev = ib_get_client_data(device, &srp_client);

        list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
                device_unregister(&host->dev);
                /*
                 * Wait for the sysfs entry to go away, so that no new
                 * target ports can be created.
                 */
                wait_for_completion(&host->released);

                /*
                 * Mark all target ports as removed, so we stop queueing
                 * commands and don't try to reconnect.
                 */
                spin_lock(&host->target_lock);
                list_for_each_entry(target, &host->target_list, list) {
                        spin_lock_irq(target->scsi_host->host_lock);
                        target->state = SRP_TARGET_REMOVED;
                        spin_unlock_irq(target->scsi_host->host_lock);
                }
                spin_unlock(&host->target_lock);

                /*
                 * Wait for any reconnection tasks that may have
                 * started before we marked our target ports as
                 * removed, and any target port removal tasks.
                 */
                flush_scheduled_work();

                list_for_each_entry_safe(target, tmp_target,
                                         &host->target_list, list) {
                        srp_remove_host(target->scsi_host);
                        scsi_remove_host(target->scsi_host);
                        srp_disconnect_target(target);
                        ib_destroy_cm_id(target->cm_id);
                        srp_free_target_ib(target);
                        scsi_host_put(target->scsi_host);
                }

                kfree(host);
        }

        if (srp_dev->fmr_pool)
                ib_destroy_fmr_pool(srp_dev->fmr_pool);
        ib_dereg_mr(srp_dev->mr);
        ib_dealloc_pd(srp_dev->pd);

        kfree(srp_dev);
}

static struct srp_function_template ib_srp_transport_functions = {
};

static int __init srp_init_module(void)
{
        int ret;

        if (srp_sg_tablesize > 255) {
                printk(KERN_WARNING PFX "Clamping srp_sg_tablesize to 255\n");
                srp_sg_tablesize = 255;
        }

        ib_srp_transport_template =
                srp_attach_transport(&ib_srp_transport_functions);
        if (!ib_srp_transport_template)
                return -ENOMEM;

        srp_template.sg_tablesize = srp_sg_tablesize;
        srp_max_iu_len = (sizeof (struct srp_cmd) +
                          sizeof (struct srp_indirect_buf) +
                          srp_sg_tablesize * 16);

        ret = class_register(&srp_class);
        if (ret) {
                printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
                srp_release_transport(ib_srp_transport_template);
                return ret;
        }

        ib_sa_register_client(&srp_sa_client);

        ret = ib_register_client(&srp_client);
        if (ret) {
                printk(KERN_ERR PFX "couldn't register IB client\n");
                srp_release_transport(ib_srp_transport_template);
                ib_sa_unregister_client(&srp_sa_client);
                class_unregister(&srp_class);
                return ret;
        }

        return 0;
}

static void __exit srp_cleanup_module(void)
{
        ib_unregister_client(&srp_client);
        ib_sa_unregister_client(&srp_sa_client);
        class_unregister(&srp_class);
        srp_release_transport(ib_srp_transport_template);
}

module_init(srp_init_module);
module_exit(srp_cleanup_module);