8 files changed, 107 insertions, 123 deletions

diff --git a/drivers/infiniband/hw/usnic/usnic_debugfs.c b/drivers/infiniband/hw/usnic/usnic_debugfs.c
index 92dc66cc2d50..a3115709fb03 100644
--- a/drivers/infiniband/hw/usnic/usnic_debugfs.c
+++ b/drivers/infiniband/hw/usnic/usnic_debugfs.c
@@ -165,6 +165,5 @@ void usnic_debugfs_flow_add(struct usnic_ib_qp_grp_flow *qp_flow)
 
 void usnic_debugfs_flow_remove(struct usnic_ib_qp_grp_flow *qp_flow)
 {
-	if (!IS_ERR_OR_NULL(qp_flow->dbgfs_dentry))
-		debugfs_remove(qp_flow->dbgfs_dentry);
+	debugfs_remove(qp_flow->dbgfs_dentry);
 }
diff --git a/drivers/infiniband/hw/usnic/usnic_ib_main.c b/drivers/infiniband/hw/usnic/usnic_ib_main.c
index f0538a460328..73bd00f8d2c8 100644
--- a/drivers/infiniband/hw/usnic/usnic_ib_main.c
+++ b/drivers/infiniband/hw/usnic/usnic_ib_main.c
@@ -76,7 +76,7 @@ static LIST_HEAD(usnic_ib_ibdev_list);
 static int usnic_ib_dump_vf_hdr(void *obj, char *buf, int buf_sz)
 {
 	struct usnic_ib_vf *vf = obj;
-	return scnprintf(buf, buf_sz, "PF: %s ", vf->pf->ib_dev.name);
+	return scnprintf(buf, buf_sz, "PF: %s ", dev_name(&vf->pf->ib_dev.dev));
 }
 /* End callback dump funcs */
 
@@ -138,7 +138,7 @@ static void usnic_ib_handle_usdev_event(struct usnic_ib_dev *us_ibdev,
 	netdev = us_ibdev->netdev;
 	switch (event) {
 	case NETDEV_REBOOT:
-		usnic_info("PF Reset on %s\n", us_ibdev->ib_dev.name);
+		usnic_info("PF Reset on %s\n", dev_name(&us_ibdev->ib_dev.dev));
 		usnic_ib_qp_grp_modify_active_to_err(us_ibdev);
 		ib_event.event = IB_EVENT_PORT_ERR;
 		ib_event.device = &us_ibdev->ib_dev;
@@ -151,7 +151,8 @@ static void usnic_ib_handle_usdev_event(struct usnic_ib_dev *us_ibdev,
 		if (!us_ibdev->ufdev->link_up &&
 				netif_carrier_ok(netdev)) {
 			usnic_fwd_carrier_up(us_ibdev->ufdev);
-			usnic_info("Link UP on %s\n", us_ibdev->ib_dev.name);
+			usnic_info("Link UP on %s\n",
+				   dev_name(&us_ibdev->ib_dev.dev));
 			ib_event.event = IB_EVENT_PORT_ACTIVE;
 			ib_event.device = &us_ibdev->ib_dev;
 			ib_event.element.port_num = 1;
@@ -159,7 +160,8 @@ static void usnic_ib_handle_usdev_event(struct usnic_ib_dev *us_ibdev,
 		} else if (us_ibdev->ufdev->link_up &&
 				!netif_carrier_ok(netdev)) {
 			usnic_fwd_carrier_down(us_ibdev->ufdev);
-			usnic_info("Link DOWN on %s\n", us_ibdev->ib_dev.name);
+			usnic_info("Link DOWN on %s\n",
+				   dev_name(&us_ibdev->ib_dev.dev));
 			usnic_ib_qp_grp_modify_active_to_err(us_ibdev);
 			ib_event.event = IB_EVENT_PORT_ERR;
 			ib_event.device = &us_ibdev->ib_dev;
@@ -168,17 +170,17 @@ static void usnic_ib_handle_usdev_event(struct usnic_ib_dev *us_ibdev,
 		} else {
 			usnic_dbg("Ignoring %s on %s\n",
 					netdev_cmd_to_name(event),
-					us_ibdev->ib_dev.name);
+					dev_name(&us_ibdev->ib_dev.dev));
 		}
 		break;
 	case NETDEV_CHANGEADDR:
 		if (!memcmp(us_ibdev->ufdev->mac, netdev->dev_addr,
 				sizeof(us_ibdev->ufdev->mac))) {
 			usnic_dbg("Ignoring addr change on %s\n",
-					us_ibdev->ib_dev.name);
+				  dev_name(&us_ibdev->ib_dev.dev));
 		} else {
 			usnic_info(" %s old mac: %pM new mac: %pM\n",
-					us_ibdev->ib_dev.name,
+					dev_name(&us_ibdev->ib_dev.dev),
 					us_ibdev->ufdev->mac,
 					netdev->dev_addr);
 			usnic_fwd_set_mac(us_ibdev->ufdev, netdev->dev_addr);
@@ -193,19 +195,19 @@ static void usnic_ib_handle_usdev_event(struct usnic_ib_dev *us_ibdev,
 	case NETDEV_CHANGEMTU:
 		if (us_ibdev->ufdev->mtu != netdev->mtu) {
 			usnic_info("MTU Change on %s old: %u new: %u\n",
-					us_ibdev->ib_dev.name,
+					dev_name(&us_ibdev->ib_dev.dev),
 					us_ibdev->ufdev->mtu, netdev->mtu);
 			usnic_fwd_set_mtu(us_ibdev->ufdev, netdev->mtu);
 			usnic_ib_qp_grp_modify_active_to_err(us_ibdev);
 		} else {
 			usnic_dbg("Ignoring MTU change on %s\n",
-					us_ibdev->ib_dev.name);
+				  dev_name(&us_ibdev->ib_dev.dev));
 		}
 		break;
 	default:
 		usnic_dbg("Ignoring event %s on %s",
 				netdev_cmd_to_name(event),
-				us_ibdev->ib_dev.name);
+				dev_name(&us_ibdev->ib_dev.dev));
 	}
 	mutex_unlock(&us_ibdev->usdev_lock);
 }
@@ -267,7 +269,7 @@ static int usnic_ib_handle_inet_event(struct usnic_ib_dev *us_ibdev,
 	default:
 		usnic_info("Ignoring event %s on %s",
 				netdev_cmd_to_name(event),
-				us_ibdev->ib_dev.name);
+				dev_name(&us_ibdev->ib_dev.dev));
 	}
 	mutex_unlock(&us_ibdev->usdev_lock);
 
@@ -364,7 +366,6 @@ static void *usnic_ib_device_add(struct pci_dev *dev)
 	us_ibdev->ib_dev.num_comp_vectors = USNIC_IB_NUM_COMP_VECTORS;
 	us_ibdev->ib_dev.dev.parent = &dev->dev;
 	us_ibdev->ib_dev.uverbs_abi_ver = USNIC_UVERBS_ABI_VERSION;
-	strlcpy(us_ibdev->ib_dev.name, "usnic_%d", IB_DEVICE_NAME_MAX);
 
 	us_ibdev->ib_dev.uverbs_cmd_mask =
 		(1ull << IB_USER_VERBS_CMD_GET_CONTEXT) |
@@ -416,7 +417,9 @@ static void *usnic_ib_device_add(struct pci_dev *dev)
 
 
 	us_ibdev->ib_dev.driver_id = RDMA_DRIVER_USNIC;
-	if (ib_register_device(&us_ibdev->ib_dev, NULL))
+	rdma_set_device_sysfs_group(&us_ibdev->ib_dev, &usnic_attr_group);
+
+	if (ib_register_device(&us_ibdev->ib_dev, "usnic_%d", NULL))
 		goto err_fwd_dealloc;
 
 	usnic_fwd_set_mtu(us_ibdev->ufdev, us_ibdev->netdev->mtu);
@@ -437,9 +440,9 @@ static void *usnic_ib_device_add(struct pci_dev *dev)
 	kref_init(&us_ibdev->vf_cnt);
 
 	usnic_info("Added ibdev: %s netdev: %s with mac %pM Link: %u MTU: %u\n",
-			us_ibdev->ib_dev.name, netdev_name(us_ibdev->netdev),
-			us_ibdev->ufdev->mac, us_ibdev->ufdev->link_up,
-			us_ibdev->ufdev->mtu);
+		   dev_name(&us_ibdev->ib_dev.dev),
+		   netdev_name(us_ibdev->netdev), us_ibdev->ufdev->mac,
+		   us_ibdev->ufdev->link_up, us_ibdev->ufdev->mtu);
 	return us_ibdev;
 
 err_fwd_dealloc:
@@ -452,7 +455,7 @@ err_dealloc:
 
 static void usnic_ib_device_remove(struct usnic_ib_dev *us_ibdev)
 {
-	usnic_info("Unregistering %s\n", us_ibdev->ib_dev.name);
+	usnic_info("Unregistering %s\n", dev_name(&us_ibdev->ib_dev.dev));
 	usnic_ib_sysfs_unregister_usdev(us_ibdev);
 	usnic_fwd_dev_free(us_ibdev->ufdev);
 	ib_unregister_device(&us_ibdev->ib_dev);
@@ -591,7 +594,7 @@ static int usnic_ib_pci_probe(struct pci_dev *pdev,
 	mutex_unlock(&pf->usdev_lock);
 
 	usnic_info("Registering usnic VF %s into PF %s\n", pci_name(pdev),
-			pf->ib_dev.name);
+		   dev_name(&pf->ib_dev.dev));
 	usnic_ib_log_vf(vf);
 	return 0;
 
diff --git a/drivers/infiniband/hw/usnic/usnic_ib_sysfs.c b/drivers/infiniband/hw/usnic/usnic_ib_sysfs.c
index 4210ca14014d..a7e4b2ccfaf8 100644
--- a/drivers/infiniband/hw/usnic/usnic_ib_sysfs.c
+++ b/drivers/infiniband/hw/usnic/usnic_ib_sysfs.c
@@ -46,9 +46,8 @@
 #include "usnic_ib_sysfs.h"
 #include "usnic_log.h"
 
-static ssize_t usnic_ib_show_board(struct device *device,
-					struct device_attribute *attr,
-					char *buf)
+static ssize_t board_id_show(struct device *device,
+			     struct device_attribute *attr, char *buf)
 {
 	struct usnic_ib_dev *us_ibdev =
 		container_of(device, struct usnic_ib_dev, ib_dev.dev);
@@ -60,13 +59,13 @@ static ssize_t usnic_ib_show_board(struct device *device,
 
 	return scnprintf(buf, PAGE_SIZE, "%hu\n", subsystem_device_id);
 }
+static DEVICE_ATTR_RO(board_id);
 
 /*
  * Report the configuration for this PF
  */
 static ssize_t
-usnic_ib_show_config(struct device *device, struct device_attribute *attr,
-			char *buf)
+config_show(struct device *device, struct device_attribute *attr, char *buf)
 {
 	struct usnic_ib_dev *us_ibdev;
 	char *ptr;
@@ -94,7 +93,7 @@ usnic_ib_show_config(struct device *device, struct device_attribute *attr,
 
 		n = scnprintf(ptr, left,
 			"%s: %s:%d.%d, %s, %pM, %u VFs\n Per VF:",
-			us_ibdev->ib_dev.name,
+			dev_name(&us_ibdev->ib_dev.dev),
 			busname,
 			PCI_SLOT(us_ibdev->pdev->devfn),
 			PCI_FUNC(us_ibdev->pdev->devfn),
@@ -119,17 +118,17 @@ usnic_ib_show_config(struct device *device, struct device_attribute *attr,
 		UPDATE_PTR_LEFT(n, ptr, left);
 	} else {
 		n = scnprintf(ptr, left, "%s: no VFs\n",
-				us_ibdev->ib_dev.name);
+				dev_name(&us_ibdev->ib_dev.dev));
 		UPDATE_PTR_LEFT(n, ptr, left);
 	}
 	mutex_unlock(&us_ibdev->usdev_lock);
 
 	return ptr - buf;
 }
+static DEVICE_ATTR_RO(config);
 
 static ssize_t
-usnic_ib_show_iface(struct device *device, struct device_attribute *attr,
-			char *buf)
+iface_show(struct device *device, struct device_attribute *attr, char *buf)
 {
 	struct usnic_ib_dev *us_ibdev;
 
@@ -138,10 +137,10 @@ usnic_ib_show_iface(struct device *device, struct device_attribute *attr,
 	return scnprintf(buf, PAGE_SIZE, "%s\n",
 			netdev_name(us_ibdev->netdev));
 }
+static DEVICE_ATTR_RO(iface);
 
 static ssize_t
-usnic_ib_show_max_vf(struct device *device, struct device_attribute *attr,
-			char *buf)
+max_vf_show(struct device *device, struct device_attribute *attr, char *buf)
 {
 	struct usnic_ib_dev *us_ibdev;
 
@@ -150,10 +149,10 @@ usnic_ib_show_max_vf(struct device *device, struct device_attribute *attr,
 	return scnprintf(buf, PAGE_SIZE, "%u\n",
 			kref_read(&us_ibdev->vf_cnt));
 }
+static DEVICE_ATTR_RO(max_vf);
 
 static ssize_t
-usnic_ib_show_qp_per_vf(struct device *device, struct device_attribute *attr,
-			char *buf)
+qp_per_vf_show(struct device *device, struct device_attribute *attr, char *buf)
 {
 	struct usnic_ib_dev *us_ibdev;
 	int qp_per_vf;
@@ -165,10 +164,10 @@ usnic_ib_show_qp_per_vf(struct device *device, struct device_attribute *attr,
 	return scnprintf(buf, PAGE_SIZE,
 				"%d\n", qp_per_vf);
 }
+static DEVICE_ATTR_RO(qp_per_vf);
 
 static ssize_t
-usnic_ib_show_cq_per_vf(struct device *device, struct device_attribute *attr,
-			char *buf)
+cq_per_vf_show(struct device *device, struct device_attribute *attr, char *buf)
 {
 	struct usnic_ib_dev *us_ibdev;
 
@@ -177,21 +176,20 @@ usnic_ib_show_cq_per_vf(struct device *device, struct device_attribute *attr,
 	return scnprintf(buf, PAGE_SIZE, "%d\n",
 			us_ibdev->vf_res_cnt[USNIC_VNIC_RES_TYPE_CQ]);
 }
+static DEVICE_ATTR_RO(cq_per_vf);
+
+static struct attribute *usnic_class_attributes[] = {
+	&dev_attr_board_id.attr,
+	&dev_attr_config.attr,
+	&dev_attr_iface.attr,
+	&dev_attr_max_vf.attr,
+	&dev_attr_qp_per_vf.attr,
+	&dev_attr_cq_per_vf.attr,
+	NULL
+};
 
-static DEVICE_ATTR(board_id, S_IRUGO, usnic_ib_show_board, NULL);
-static DEVICE_ATTR(config, S_IRUGO, usnic_ib_show_config, NULL);
-static DEVICE_ATTR(iface, S_IRUGO, usnic_ib_show_iface, NULL);
-static DEVICE_ATTR(max_vf, S_IRUGO, usnic_ib_show_max_vf, NULL);
-static DEVICE_ATTR(qp_per_vf, S_IRUGO, usnic_ib_show_qp_per_vf, NULL);
-static DEVICE_ATTR(cq_per_vf, S_IRUGO, usnic_ib_show_cq_per_vf, NULL);
-
-static struct device_attribute *usnic_class_attributes[] = {
-	&dev_attr_board_id,
-	&dev_attr_config,
-	&dev_attr_iface,
-	&dev_attr_max_vf,
-	&dev_attr_qp_per_vf,
-	&dev_attr_cq_per_vf,
+const struct attribute_group usnic_attr_group = {
+	.attrs = usnic_class_attributes,
 };
 
 struct qpn_attribute {
@@ -278,18 +276,6 @@ static struct kobj_type usnic_ib_qpn_type = {
 
 int usnic_ib_sysfs_register_usdev(struct usnic_ib_dev *us_ibdev)
 {
-	int i;
-	int err;
-	for (i = 0; i < ARRAY_SIZE(usnic_class_attributes); ++i) {
-		err = device_create_file(&us_ibdev->ib_dev.dev,
-						usnic_class_attributes[i]);
-		if (err) {
-			usnic_err("Failed to create device file %d for %s eith err %d",
-				i, us_ibdev->ib_dev.name, err);
-			return -EINVAL;
-		}
-	}
-
 	/* create kernel object for looking at individual QPs */
 	kobject_get(&us_ibdev->ib_dev.dev.kobj);
 	us_ibdev->qpn_kobj = kobject_create_and_add("qpn",
@@ -304,12 +290,6 @@ int usnic_ib_sysfs_register_usdev(struct usnic_ib_dev *us_ibdev)
 
 void usnic_ib_sysfs_unregister_usdev(struct usnic_ib_dev *us_ibdev)
 {
-	int i;
-	for (i = 0; i < ARRAY_SIZE(usnic_class_attributes); ++i) {
-		device_remove_file(&us_ibdev->ib_dev.dev,
-					usnic_class_attributes[i]);
-	}
-
 	kobject_put(us_ibdev->qpn_kobj);
 }
 
diff --git a/drivers/infiniband/hw/usnic/usnic_ib_sysfs.h b/drivers/infiniband/hw/usnic/usnic_ib_sysfs.h
index 3d98e16cfeaf..b1f064cec850 100644
--- a/drivers/infiniband/hw/usnic/usnic_ib_sysfs.h
+++ b/drivers/infiniband/hw/usnic/usnic_ib_sysfs.h
@@ -41,4 +41,6 @@ void usnic_ib_sysfs_unregister_usdev(struct usnic_ib_dev *us_ibdev);
 void usnic_ib_sysfs_qpn_add(struct usnic_ib_qp_grp *qp_grp);
 void usnic_ib_sysfs_qpn_remove(struct usnic_ib_qp_grp *qp_grp);
 
+extern const struct attribute_group usnic_attr_group;
+
 #endif /* !USNIC_IB_SYSFS_H_ */
diff --git a/drivers/infiniband/hw/usnic/usnic_ib_verbs.c b/drivers/infiniband/hw/usnic/usnic_ib_verbs.c
index 9973ac893635..0b91ff36768a 100644
--- a/drivers/infiniband/hw/usnic/usnic_ib_verbs.c
+++ b/drivers/infiniband/hw/usnic/usnic_ib_verbs.c
@@ -159,7 +159,8 @@ static int usnic_ib_fill_create_qp_resp(struct usnic_ib_qp_grp *qp_grp,
 
 	err = ib_copy_to_udata(udata, &resp, sizeof(resp));
 	if (err) {
-		usnic_err("Failed to copy udata for %s", us_ibdev->ib_dev.name);
+		usnic_err("Failed to copy udata for %s",
+			  dev_name(&us_ibdev->ib_dev.dev));
 		return err;
 	}
 
@@ -197,7 +198,7 @@ find_free_vf_and_create_qp_grp(struct usnic_ib_dev *us_ibdev,
 			vnic = vf->vnic;
 			if (!usnic_vnic_check_room(vnic, res_spec)) {
 				usnic_dbg("Found used vnic %s from %s\n",
-						us_ibdev->ib_dev.name,
+						dev_name(&us_ibdev->ib_dev.dev),
 						pci_name(usnic_vnic_get_pdev(
 									vnic)));
 				qp_grp = usnic_ib_qp_grp_create(us_ibdev->ufdev,
@@ -230,7 +231,8 @@ find_free_vf_and_create_qp_grp(struct usnic_ib_dev *us_ibdev,
 		spin_unlock(&vf->lock);
 	}
 
-	usnic_info("No free qp grp found on %s\n", us_ibdev->ib_dev.name);
+	usnic_info("No free qp grp found on %s\n",
+		   dev_name(&us_ibdev->ib_dev.dev));
 	return ERR_PTR(-ENOMEM);
 
 qp_grp_check:
@@ -471,7 +473,7 @@ struct ib_pd *usnic_ib_alloc_pd(struct ib_device *ibdev,
 	}
 
 	usnic_info("domain 0x%p allocated for context 0x%p and device %s\n",
-			pd, context, ibdev->name);
+		   pd, context, dev_name(&ibdev->dev));
 	return &pd->ibpd;
 }
 
@@ -508,20 +510,20 @@ struct ib_qp *usnic_ib_create_qp(struct ib_pd *pd,
 	err = ib_copy_from_udata(&cmd, udata, sizeof(cmd));
 	if (err) {
 		usnic_err("%s: cannot copy udata for create_qp\n",
-				us_ibdev->ib_dev.name);
+			  dev_name(&us_ibdev->ib_dev.dev));
 		return ERR_PTR(-EINVAL);
 	}
 
 	err = create_qp_validate_user_data(cmd);
 	if (err) {
 		usnic_err("%s: Failed to validate user data\n",
-				us_ibdev->ib_dev.name);
+			  dev_name(&us_ibdev->ib_dev.dev));
 		return ERR_PTR(-EINVAL);
 	}
 
 	if (init_attr->qp_type != IB_QPT_UD) {
 		usnic_err("%s asked to make a non-UD QP: %d\n",
-				us_ibdev->ib_dev.name, init_attr->qp_type);
+			  dev_name(&us_ibdev->ib_dev.dev), init_attr->qp_type);
 		return ERR_PTR(-EINVAL);
 	}
 
diff --git a/drivers/infiniband/hw/usnic/usnic_transport.c b/drivers/infiniband/hw/usnic/usnic_transport.c
index e0a95538c364..82dd810bc000 100644
--- a/drivers/infiniband/hw/usnic/usnic_transport.c
+++ b/drivers/infiniband/hw/usnic/usnic_transport.c
@@ -121,7 +121,7 @@ void usnic_transport_unrsrv_port(enum usnic_transport_type type, u16 port_num)
 	if (type == USNIC_TRANSPORT_ROCE_CUSTOM) {
 		spin_lock(&roce_bitmap_lock);
 		if (!port_num) {
-			usnic_err("Unreserved unvalid port num 0 for %s\n",
+			usnic_err("Unreserved invalid port num 0 for %s\n",
 					usnic_transport_to_str(type));
 			goto out_roce_custom;
 		}
diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/hw/usnic/usnic_uiom.c
index 9dd39daa602b..49275a548751 100644
--- a/drivers/infiniband/hw/usnic/usnic_uiom.c
+++ b/drivers/infiniband/hw/usnic/usnic_uiom.c
@@ -54,18 +54,6 @@ static struct workqueue_struct *usnic_uiom_wq;
 	((void *) &((struct usnic_uiom_chunk *) 0)->page_list[1] -	\
 	(void *) &((struct usnic_uiom_chunk *) 0)->page_list[0]))
 
-static void usnic_uiom_reg_account(struct work_struct *work)
-{
-	struct usnic_uiom_reg *umem = container_of(work,
-						struct usnic_uiom_reg, work);
-
-	down_write(&umem->mm->mmap_sem);
-	umem->mm->locked_vm -= umem->diff;
-	up_write(&umem->mm->mmap_sem);
-	mmput(umem->mm);
-	kfree(umem);
-}
-
 static int usnic_uiom_dma_fault(struct iommu_domain *domain,
 				struct device *dev,
 				unsigned long iova, int flags,
@@ -99,8 +87,9 @@ static void usnic_uiom_put_pages(struct list_head *chunk_list, int dirty)
 }
 
 static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
-				int dmasync, struct list_head *chunk_list)
+				int dmasync, struct usnic_uiom_reg *uiomr)
 {
+	struct list_head *chunk_list = &uiomr->chunk_list;
 	struct page **page_list;
 	struct scatterlist *sg;
 	struct usnic_uiom_chunk *chunk;
@@ -114,6 +103,7 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
 	int flags;
 	dma_addr_t pa;
 	unsigned int gup_flags;
+	struct mm_struct *mm;
 
 	/*
 	 * If the combination of the addr and size requested for this memory
@@ -136,7 +126,8 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
 
 	npages = PAGE_ALIGN(size + (addr & ~PAGE_MASK)) >> PAGE_SHIFT;
 
-	down_write(&current->mm->mmap_sem);
+	uiomr->owning_mm = mm = current->mm;
+	down_write(&mm->mmap_sem);
 
 	locked = npages + current->mm->pinned_vm;
 	lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
@@ -196,10 +187,12 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
 out:
 	if (ret < 0)
 		usnic_uiom_put_pages(chunk_list, 0);
-	else
-		current->mm->pinned_vm = locked;
+	else {
+		mm->pinned_vm = locked;
+		mmgrab(uiomr->owning_mm);
+	}
 
-	up_write(&current->mm->mmap_sem);
+	up_write(&mm->mmap_sem);
 	free_page((unsigned long) page_list);
 	return ret;
 }
@@ -379,7 +372,7 @@ struct usnic_uiom_reg *usnic_uiom_reg_get(struct usnic_uiom_pd *pd,
 	uiomr->pd = pd;
 
 	err = usnic_uiom_get_pages(addr, size, writable, dmasync,
-					&uiomr->chunk_list);
+				   uiomr);
 	if (err) {
 		usnic_err("Failed get_pages vpn [0x%lx,0x%lx] err %d\n",
 				vpn_start, vpn_last, err);
@@ -426,29 +419,39 @@ out_put_intervals:
 out_put_pages:
 	usnic_uiom_put_pages(&uiomr->chunk_list, 0);
 	spin_unlock(&pd->lock);
+	mmdrop(uiomr->owning_mm);
 out_free_uiomr:
 	kfree(uiomr);
 	return ERR_PTR(err);
 }
 
-void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr,
-			    struct ib_ucontext *ucontext)
+static void __usnic_uiom_release_tail(struct usnic_uiom_reg *uiomr)
 {
-	struct task_struct *task;
-	struct mm_struct *mm;
-	unsigned long diff;
+	mmdrop(uiomr->owning_mm);
+	kfree(uiomr);
+}
 
-	__usnic_uiom_reg_release(uiomr->pd, uiomr, 1);
+static inline size_t usnic_uiom_num_pages(struct usnic_uiom_reg *uiomr)
+{
+	return PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT;
+}
 
-	task = get_pid_task(ucontext->tgid, PIDTYPE_PID);
-	if (!task)
-		goto out;
-	mm = get_task_mm(task);
-	put_task_struct(task);
-	if (!mm)
-		goto out;
+static void usnic_uiom_release_defer(struct work_struct *work)
+{
+	struct usnic_uiom_reg *uiomr =
+		container_of(work, struct usnic_uiom_reg, work);
 
-	diff = PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT;
+	down_write(&uiomr->owning_mm->mmap_sem);
+	uiomr->owning_mm->pinned_vm -= usnic_uiom_num_pages(uiomr);
+	up_write(&uiomr->owning_mm->mmap_sem);
+
+	__usnic_uiom_release_tail(uiomr);
+}
+
+void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr,
+			    struct ib_ucontext *context)
+{
+	__usnic_uiom_reg_release(uiomr->pd, uiomr, 1);
 
 	/*
 	 * We may be called with the mm's mmap_sem already held.  This
@@ -456,25 +459,21 @@ void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr,
 	 * the last reference to our file and calls our release
 	 * method.  If there are memory regions to destroy, we'll end
 	 * up here and not be able to take the mmap_sem.  In that case
-	 * we defer the vm_locked accounting to the system workqueue.
+	 * we defer the vm_locked accounting to a workqueue.
 	 */
-	if (ucontext->closing) {
-		if (!down_write_trylock(&mm->mmap_sem)) {
-			INIT_WORK(&uiomr->work, usnic_uiom_reg_account);
-			uiomr->mm = mm;
-			uiomr->diff = diff;
-
+	if (context->closing) {
+		if (!down_write_trylock(&uiomr->owning_mm->mmap_sem)) {
+			INIT_WORK(&uiomr->work, usnic_uiom_release_defer);
 			queue_work(usnic_uiom_wq, &uiomr->work);
 			return;
 		}
-	} else
-		down_write(&mm->mmap_sem);
+	} else {
+		down_write(&uiomr->owning_mm->mmap_sem);
+	}
+	uiomr->owning_mm->pinned_vm -= usnic_uiom_num_pages(uiomr);
+	up_write(&uiomr->owning_mm->mmap_sem);
 
-	mm->pinned_vm -= diff;
-	up_write(&mm->mmap_sem);
-	mmput(mm);
-out:
-	kfree(uiomr);
+	__usnic_uiom_release_tail(uiomr);
 }
 
 struct usnic_uiom_pd *usnic_uiom_alloc_pd(void)
diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.h b/drivers/infiniband/hw/usnic/usnic_uiom.h
index 8c096acff123..b86a9731071b 100644
--- a/drivers/infiniband/hw/usnic/usnic_uiom.h
+++ b/drivers/infiniband/hw/usnic/usnic_uiom.h
@@ -71,8 +71,7 @@ struct usnic_uiom_reg {
 	int				writable;
 	struct list_head		chunk_list;
 	struct work_struct		work;
-	struct mm_struct		*mm;
-	unsigned long			diff;
+	struct mm_struct		*owning_mm;
 };
 
 struct usnic_uiom_chunk {