IB/srp: Use FMRs to map gather/scatter lists

Create an SRP FMR pool on HCAs that support FMRs, and use FMRs to map
gather/scatter lists that have more than one entry into a single
memory region that appears virtually contiguous to the SRP target
(which is the RDMA initiator).

This patch bails out on FMR mapping for SCSI commands where the
gather/scatter list cannot be mapped into a single FMR because there
are sub-page-sized entries in middle of the list.  An unaligned
start or end of the list is OK.

Based on a patch by Vu Pham <vuhuong@mellanox.com>.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

2 files changed, 228 insertions, 87 deletions

diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 9cbdffa08dc2..9c373139ee63 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -105,7 +105,8 @@ static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
         if (!iu->buf)
                 goto out_free_iu;
 
-        iu->dma = dma_map_single(host->dev->dma_device, iu->buf, size, direction);
+        iu->dma = dma_map_single(host->dev->dev->dma_device,
+                                 iu->buf, size, direction);
         if (dma_mapping_error(iu->dma))
                 goto out_free_buf;
 
@@ -127,7 +128,8 @@ static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
         if (!iu)
                 return;
 
-        dma_unmap_single(host->dev->dma_device, iu->dma, iu->size, iu->direction);
+        dma_unmap_single(host->dev->dev->dma_device,
+                         iu->dma, iu->size, iu->direction);
         kfree(iu->buf);
         kfree(iu);
 }
@@ -147,7 +149,7 @@ static int srp_init_qp(struct srp_target_port *target,
         if (!attr)
                 return -ENOMEM;
 
-        ret = ib_find_cached_pkey(target->srp_host->dev,
+        ret = ib_find_cached_pkey(target->srp_host->dev->dev,
                                   target->srp_host->port,
                                   be16_to_cpu(target->path.pkey),
                                   &attr->pkey_index);
@@ -179,7 +181,7 @@ static int srp_create_target_ib(struct srp_target_port *target)
         if (!init_attr)
                 return -ENOMEM;
 
-        target->cq = ib_create_cq(target->srp_host->dev, srp_completion,
+        target->cq = ib_create_cq(target->srp_host->dev->dev, srp_completion,
                                   NULL, target, SRP_CQ_SIZE);
         if (IS_ERR(target->cq)) {
                 ret = PTR_ERR(target->cq);
@@ -198,7 +200,7 @@ static int srp_create_target_ib(struct srp_target_port *target)
         init_attr->send_cq             = target->cq;
         init_attr->recv_cq             = target->cq;
 
-        target->qp = ib_create_qp(target->srp_host->pd, init_attr);
+        target->qp = ib_create_qp(target->srp_host->dev->pd, init_attr);
         if (IS_ERR(target->qp)) {
                 ret = PTR_ERR(target->qp);
                 ib_destroy_cq(target->cq);
@@ -250,7 +252,7 @@ static int srp_lookup_path(struct srp_target_port *target)
 
         init_completion(&target->done);
 
-        target->path_query_id = ib_sa_path_rec_get(target->srp_host->dev,
+        target->path_query_id = ib_sa_path_rec_get(target->srp_host->dev->dev,
                                                    target->srp_host->port,
                                                    &target->path,
                                                    IB_SA_PATH_REC_DGID          |
@@ -421,6 +423,11 @@ static void srp_unmap_data(struct scsi_cmnd *scmnd,
              scmnd->sc_data_direction != DMA_FROM_DEVICE))
                 return;
 
+        if (req->fmr) {
+                ib_fmr_pool_unmap(req->fmr);
+                req->fmr = NULL;
+        }
+
         /*
          * This handling of non-SG commands can be killed when the
          * SCSI midlayer no longer generates non-SG commands.
@@ -433,7 +440,7 @@ static void srp_unmap_data(struct scsi_cmnd *scmnd,
                 scat  = &req->fake_sg;
         }
 
-        dma_unmap_sg(target->srp_host->dev->dma_device, scat, nents,
+        dma_unmap_sg(target->srp_host->dev->dev->dma_device, scat, nents,
                      scmnd->sc_data_direction);
 }
 
@@ -459,7 +466,7 @@ static int srp_reconnect_target(struct srp_target_port *target)
          * Now get a new local CM ID so that we avoid confusing the
          * target in case things are really fouled up.
          */
-        new_cm_id = ib_create_cm_id(target->srp_host->dev,
+        new_cm_id = ib_create_cm_id(target->srp_host->dev->dev,
                                     srp_cm_handler, target);
         if (IS_ERR(new_cm_id)) {
                 ret = PTR_ERR(new_cm_id);
@@ -528,14 +535,79 @@ err:
         return ret;
 }
 
+static int srp_map_fmr(struct srp_device *dev, 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;
+
+        if (!dev->fmr_pool)
+                return -ENODEV;
+
+        len = page_cnt = 0;
+        for (i = 0; i < sg_cnt; ++i) {
+                if (sg_dma_address(&scat[i]) & ~dev->fmr_page_mask) {
+                        if (i > 0)
+                                return -EINVAL;
+                        else
+                                ++page_cnt;
+                }
+                if ((sg_dma_address(&scat[i]) + sg_dma_len(&scat[i])) &
+                    ~dev->fmr_page_mask) {
+                        if (i < sg_cnt - 1)
+                                return -EINVAL;
+                        else
+                                ++page_cnt;
+                }
+
+                len += sg_dma_len(&scat[i]);
+        }
+
+        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;
+        for (i = 0; i < sg_cnt; ++i)
+                for (j = 0; j < sg_dma_len(&scat[i]); j += dev->fmr_page_size)
+                        dma_pages[page_cnt++] =
+                                (sg_dma_address(&scat[i]) & 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);
+                goto out;
+        }
+
+        buf->va  = cpu_to_be64(sg_dma_address(&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;
-        int i;
-        u8 fmt;
+        u8 fmt = SRP_DATA_DESC_DIRECT;
 
         if (!scmnd->request_buffer || scmnd->sc_data_direction == DMA_NONE)
                 return sizeof (struct srp_cmd);
@@ -560,53 +632,63 @@ static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
                 sg_init_one(scat, scmnd->request_buffer, scmnd->request_bufflen);
         }
 
-        count = dma_map_sg(target->srp_host->dev->dma_device, scat, nents,
-                           scmnd->sc_data_direction);
+        count = dma_map_sg(target->srp_host->dev->dev->dma_device,
+                           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;
 
-                fmt = SRP_DATA_DESC_DIRECT;
-
                 buf->va  = cpu_to_be64(sg_dma_address(scat));
-                buf->key = cpu_to_be32(target->srp_host->mr->rkey);
+                buf->key = cpu_to_be32(target->srp_host->dev->mr->rkey);
                 buf->len = cpu_to_be32(sg_dma_len(scat));
-
-                len = sizeof (struct srp_cmd) +
-                        sizeof (struct srp_direct_buf);
-        } else {
+        } else if (srp_map_fmr(target->srp_host->dev, 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;
                 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);
+
+                for (i = 0; i < count; ++i) {
+                        buf->desc_list[i].va  =
+                                cpu_to_be64(sg_dma_address(&scat[i]));
+                        buf->desc_list[i].key =
+                                cpu_to_be32(target->srp_host->dev->mr->rkey);
+                        buf->desc_list[i].len =
+                                cpu_to_be32(sg_dma_len(&scat[i]));
+                        datalen += sg_dma_len(&scat[i]);
+                }
 
                 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.va  =
+                        cpu_to_be64(req->cmd->dma + sizeof *cmd + sizeof *buf);
                 buf->table_desc.key =
-                        cpu_to_be32(target->srp_host->mr->rkey);
+                        cpu_to_be32(target->srp_host->dev->mr->rkey);
                 buf->table_desc.len =
                         cpu_to_be32(count * sizeof (struct srp_direct_buf));
 
-                for (i = 0; i < count; ++i) {
-                        buf->desc_list[i].va  = cpu_to_be64(sg_dma_address(&scat[i]));
-                        buf->desc_list[i].key =
-                                cpu_to_be32(target->srp_host->mr->rkey);
-                        buf->desc_list[i].len = cpu_to_be32(sg_dma_len(&scat[i]));
-
-                        datalen += sg_dma_len(&scat[i]);
-                }
-
                 buf->len = cpu_to_be32(datalen);
-
-                len = sizeof (struct srp_cmd) +
-                        sizeof (struct srp_indirect_buf) +
-                        count * sizeof (struct srp_direct_buf);
         }
 
         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
@@ -689,7 +771,7 @@ static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
 
         iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
 
-        dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
+        dma_sync_single_for_cpu(target->srp_host->dev->dev->dma_device, iu->dma,
                                 target->max_ti_iu_len, DMA_FROM_DEVICE);
 
         opcode = *(u8 *) iu->buf;
@@ -726,7 +808,7 @@ static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
                 break;
         }
 
-        dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
+        dma_sync_single_for_device(target->srp_host->dev->dev->dma_device, iu->dma,
                                    target->max_ti_iu_len, DMA_FROM_DEVICE);
 }
 
@@ -770,7 +852,7 @@ static int __srp_post_recv(struct srp_target_port *target)
 
         list.addr   = iu->dma;
         list.length = iu->size;
-        list.lkey   = target->srp_host->mr->lkey;
+        list.lkey   = target->srp_host->dev->mr->lkey;
 
         wr.next     = NULL;
         wr.sg_list  = &list;
@@ -828,7 +910,7 @@ static int __srp_post_send(struct srp_target_port *target,
 
         list.addr   = iu->dma;
         list.length = len;
-        list.lkey   = target->srp_host->mr->lkey;
+        list.lkey   = target->srp_host->dev->mr->lkey;
 
         wr.next       = NULL;
         wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
@@ -870,7 +952,7 @@ static int srp_queuecommand(struct scsi_cmnd *scmnd,
         if (!iu)
                 goto err;
 
-        dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
+        dma_sync_single_for_cpu(target->srp_host->dev->dev->dma_device, iu->dma,
                                 SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 
         req = list_entry(target->free_reqs.next, struct srp_request, list);
@@ -903,7 +985,7 @@ static int srp_queuecommand(struct scsi_cmnd *scmnd,
                 goto err_unmap;
         }
 
-        dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
+        dma_sync_single_for_device(target->srp_host->dev->dev->dma_device, iu->dma,
                                    SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 
         if (__srp_post_send(target, iu, len)) {
@@ -1365,7 +1447,7 @@ static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
         sprintf(target->target_name, "SRP.T10:%016llX",
                  (unsigned long long) be64_to_cpu(target->id_ext));
 
-        if (scsi_add_host(target->scsi_host, host->dev->dma_device))
+        if (scsi_add_host(target->scsi_host, host->dev->dev->dma_device))
                 return -ENODEV;
 
         mutex_lock(&host->target_mutex);
@@ -1558,7 +1640,7 @@ static ssize_t srp_create_target(struct class_device *class_dev,
         if (ret)
                 goto err;
 
-        ib_get_cached_gid(host->dev, host->port, 0, &target->path.sgid);
+        ib_get_cached_gid(host->dev->dev, host->port, 0, &target->path.sgid);
 
         printk(KERN_DEBUG PFX "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
                "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
@@ -1579,7 +1661,7 @@ static ssize_t srp_create_target(struct class_device *class_dev,
         if (ret)
                 goto err;
 
-        target->cm_id = ib_create_cm_id(host->dev, srp_cm_handler, target);
+        target->cm_id = ib_create_cm_id(host->dev->dev, srp_cm_handler, target);
         if (IS_ERR(target->cm_id)) {
                 ret = PTR_ERR(target->cm_id);
                 goto err_free;
@@ -1619,7 +1701,7 @@ static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
         struct srp_host *host =
                 container_of(class_dev, struct srp_host, class_dev);
 
-        return sprintf(buf, "%s\n", host->dev->name);
+        return sprintf(buf, "%s\n", host->dev->dev->name);
 }
 
 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
@@ -1634,7 +1716,7 @@ static ssize_t show_port(struct class_device *class_dev, char *buf)
 
 static CLASS_DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
 
-static struct srp_host *srp_add_port(struct ib_device *device, u8 port)
+static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
 {
         struct srp_host *host;
 
@@ -1649,26 +1731,15 @@ static struct srp_host *srp_add_port(struct ib_device *device, u8 port)
         host->port = port;
 
         host->initiator_port_id[7] = port;
-        memcpy(host->initiator_port_id + 8, &device->node_guid, 8);
-
-        host->pd   = ib_alloc_pd(device);
-        if (IS_ERR(host->pd))
-                goto err_free;
-
-        host->mr   = ib_get_dma_mr(host->pd,
-                                   IB_ACCESS_LOCAL_WRITE |
-                                   IB_ACCESS_REMOTE_READ |
-                                   IB_ACCESS_REMOTE_WRITE);
-        if (IS_ERR(host->mr))
-                goto err_pd;
+        memcpy(host->initiator_port_id + 8, &device->dev->node_guid, 8);
 
         host->class_dev.class = &srp_class;
-        host->class_dev.dev   = device->dma_device;
+        host->class_dev.dev   = device->dev->dma_device;
         snprintf(host->class_dev.class_id, BUS_ID_SIZE, "srp-%s-%d",
-                 device->name, port);
+                 device->dev->name, port);
 
         if (class_device_register(&host->class_dev))
-                goto err_mr;
+                goto free_host;
         if (class_device_create_file(&host->class_dev, &class_device_attr_add_target))
                 goto err_class;
         if (class_device_create_file(&host->class_dev, &class_device_attr_ibdev))
@@ -1681,13 +1752,7 @@ static struct srp_host *srp_add_port(struct ib_device *device, u8 port)
 err_class:
         class_device_unregister(&host->class_dev);
 
-err_mr:
-        ib_dereg_mr(host->mr);
-
-err_pd:
-        ib_dealloc_pd(host->pd);
-
-err_free:
+free_host:
         kfree(host);
 
         return NULL;
@@ -1695,15 +1760,62 @@ err_free:
 
 static void srp_add_one(struct ib_device *device)
 {
-        struct list_head *dev_list;
+        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_list = kmalloc(sizeof *dev_list, GFP_KERNEL);
-        if (!dev_list)
+        dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
+        if (!dev_attr)
                 return;
 
-        INIT_LIST_HEAD(dev_list);
+        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  = ~((unsigned long) 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 == IB_NODE_SWITCH) {
                 s = 0;
@@ -1714,25 +1826,36 @@ static void srp_add_one(struct ib_device *device)
         }
 
         for (p = s; p <= e; ++p) {
-                host = srp_add_port(device, p);
+                host = srp_add_port(srp_dev, p);
                 if (host)
-                        list_add_tail(&host->list, dev_list);
+                        list_add_tail(&host->list, &srp_dev->dev_list);
         }
 
-        ib_set_client_data(device, &srp_client, 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 list_head *dev_list;
+        struct srp_device *srp_dev;
         struct srp_host *host, *tmp_host;
         LIST_HEAD(target_list);
         struct srp_target_port *target, *tmp_target;
         unsigned long flags;
 
-        dev_list = ib_get_client_data(device, &srp_client);
+        srp_dev = ib_get_client_data(device, &srp_client);
 
-        list_for_each_entry_safe(host, tmp_host, dev_list, list) {
+        list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
                 class_device_unregister(&host->class_dev);
                 /*
                  * Wait for the sysfs entry to go away, so that no new
@@ -1770,12 +1893,15 @@ static void srp_remove_one(struct ib_device *device)
                         scsi_host_put(target->scsi_host);
                 }
 
-                ib_dereg_mr(host->mr);
-                ib_dealloc_pd(host->pd);
                 kfree(host);
         }
 
-        kfree(dev_list);
+        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 int __init srp_init_module(void)
diff --git a/drivers/infiniband/ulp/srp/ib_srp.h b/drivers/infiniband/ulp/srp/ib_srp.h
index c5cd43aae860..5ecda4ad8906 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -46,6 +46,7 @@
 #include <rdma/ib_verbs.h>
 #include <rdma/ib_sa.h>
 #include <rdma/ib_cm.h>
+#include <rdma/ib_fmr_pool.h>
 
 enum {
         SRP_PATH_REC_TIMEOUT_MS = 1000,
@@ -62,7 +63,11 @@ enum {
         SRP_SQ_SIZE             = SRP_RQ_SIZE - 1,
         SRP_CQ_SIZE             = SRP_SQ_SIZE + SRP_RQ_SIZE,
 
-        SRP_TAG_TSK_MGMT        = 1 << (SRP_RQ_SHIFT + 1)
+        SRP_TAG_TSK_MGMT        = 1 << (SRP_RQ_SHIFT + 1),
+
+        SRP_FMR_SIZE            = 256,
+        SRP_FMR_POOL_SIZE       = 1024,
+        SRP_FMR_DIRTY_SIZE      = SRP_FMR_POOL_SIZE / 4
 };
 
 #define SRP_OP_RECV             (1 << 31)
@@ -77,15 +82,24 @@ enum srp_target_state {
         SRP_TARGET_REMOVED
 };
 
-struct srp_host {
-        u8                      initiator_port_id[16];
+struct srp_device {
+        struct list_head        dev_list;
         struct ib_device       *dev;
-        u8                      port;
         struct ib_pd           *pd;
         struct ib_mr           *mr;
+        struct ib_fmr_pool     *fmr_pool;
+        int                     fmr_page_shift;
+        int                     fmr_page_size;
+        unsigned long           fmr_page_mask;
+};
+
+struct srp_host {
+        u8                      initiator_port_id[16];
+        struct srp_device      *dev;
+        u8                      port;
         struct class_device     class_dev;
         struct list_head        target_list;
-        struct mutex            target_mutex;
+        struct mutex            target_mutex;
         struct completion       released;
         struct list_head        list;
 };
@@ -95,6 +109,7 @@ struct srp_request {
         struct scsi_cmnd       *scmnd;
         struct srp_iu          *cmd;
         struct srp_iu          *tsk_mgmt;
+        struct ib_pool_fmr     *fmr;
         /*
          * Fake scatterlist used when scmnd->use_sg==0.  Can be killed
          * when the SCSI midlayer no longer generates non-SG commands.