X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Finfiniband%2Fcore%2Fuser_mad.c;h=afe70a549c2faa439901a0f27b5578f1fa154c8d;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=9d912d6877ffc01ed55943b15a55ae7230f23a6a;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git

diff --git a/drivers/infiniband/core/user_mad.c b/drivers/infiniband/core/user_mad.c
index 9d912d687..afe70a549 100644
--- a/drivers/infiniband/core/user_mad.c
+++ b/drivers/infiniband/core/user_mad.c
@@ -1,5 +1,7 @@
 /*
  * Copyright (c) 2004 Topspin Communications.  All rights reserved.
+ * Copyright (c) 2005 Voltaire, Inc. All rights reserved. 
+ * Copyright (c) 2005 Sun Microsystems, Inc. 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
@@ -29,7 +31,7 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  *
- * $Id: user_mad.c 1389 2004-12-27 22:56:47Z roland $
+ * $Id: user_mad.c 5596 2006-03-03 01:00:07Z sean.hefty $
  */
 
 #include <linux/module.h>
@@ -47,8 +49,8 @@
 #include <asm/uaccess.h>
 #include <asm/semaphore.h>
 
-#include <ib_mad.h>
-#include <ib_user_mad.h>
+#include <rdma/ib_mad.h>
+#include <rdma/ib_user_mad.h>
 
 MODULE_AUTHOR("Roland Dreier");
 MODULE_DESCRIPTION("InfiniBand userspace MAD packet access");
@@ -62,18 +64,42 @@ enum {
 	IB_UMAD_MINOR_BASE = 0
 };
 
+/*
+ * Our lifetime rules for these structs are the following: each time a
+ * device special file is opened, we look up the corresponding struct
+ * ib_umad_port by minor in the umad_port[] table while holding the
+ * port_lock.  If this lookup succeeds, we take a reference on the
+ * ib_umad_port's struct ib_umad_device while still holding the
+ * port_lock; if the lookup fails, we fail the open().  We drop these
+ * references in the corresponding close().
+ *
+ * In addition to references coming from open character devices, there
+ * is one more reference to each ib_umad_device representing the
+ * module's reference taken when allocating the ib_umad_device in
+ * ib_umad_add_one().
+ *
+ * When destroying an ib_umad_device, we clear all of its
+ * ib_umad_ports from umad_port[] while holding port_lock before
+ * dropping the module's reference to the ib_umad_device.  This is
+ * always safe because any open() calls will either succeed and obtain
+ * a reference before we clear the umad_port[] entries, or fail after
+ * we clear the umad_port[] entries.
+ */
+
 struct ib_umad_port {
-	int                    devnum;
-	struct cdev            dev;
-	struct class_device    class_dev;
+	struct cdev           *dev;
+	struct class_device   *class_dev;
 
-	int                    sm_devnum;
-	struct cdev            sm_dev;
-	struct class_device    sm_class_dev;
+	struct cdev           *sm_dev;
+	struct class_device   *sm_class_dev;
 	struct semaphore       sm_sem;
 
+	struct rw_semaphore    mutex;
+	struct list_head       file_list;
+
 	struct ib_device      *ib_dev;
 	struct ib_umad_device *umad_dev;
+	int                    dev_num;
 	u8                     port_num;
 };
 
@@ -84,40 +110,60 @@ struct ib_umad_device {
 };
 
 struct ib_umad_file {
-	struct ib_umad_port *port;
-	spinlock_t           recv_lock;
-	struct list_head     recv_list;
-	wait_queue_head_t    recv_wait;
-	struct rw_semaphore  agent_mutex;
-	struct ib_mad_agent *agent[IB_UMAD_MAX_AGENTS];
-	struct ib_mr        *mr[IB_UMAD_MAX_AGENTS];
+	struct ib_umad_port    *port;
+	struct list_head	recv_list;
+	struct list_head	port_list;
+	spinlock_t		recv_lock;
+	wait_queue_head_t	recv_wait;
+	struct ib_mad_agent    *agent[IB_UMAD_MAX_AGENTS];
+	int			agents_dead;
 };
 
 struct ib_umad_packet {
-	struct ib_user_mad mad;
-	struct ib_ah      *ah;
+	struct ib_mad_send_buf *msg;
+	struct ib_mad_recv_wc  *recv_wc;
 	struct list_head   list;
-	DECLARE_PCI_UNMAP_ADDR(mapping)
+	int		   length;
+	struct ib_user_mad mad;
 };
 
+static struct class *umad_class;
+
 static const dev_t base_dev = MKDEV(IB_UMAD_MAJOR, IB_UMAD_MINOR_BASE);
-static spinlock_t map_lock;
+
+static DEFINE_SPINLOCK(port_lock);
+static struct ib_umad_port *umad_port[IB_UMAD_MAX_PORTS];
 static DECLARE_BITMAP(dev_map, IB_UMAD_MAX_PORTS * 2);
 
 static void ib_umad_add_one(struct ib_device *device);
 static void ib_umad_remove_one(struct ib_device *device);
 
+static void ib_umad_release_dev(struct kref *ref)
+{
+	struct ib_umad_device *dev =
+		container_of(ref, struct ib_umad_device, ref);
+
+	kfree(dev);
+}
+
+/* caller must hold port->mutex at least for reading */
+static struct ib_mad_agent *__get_agent(struct ib_umad_file *file, int id)
+{
+	return file->agents_dead ? NULL : file->agent[id];
+}
+
 static int queue_packet(struct ib_umad_file *file,
 			struct ib_mad_agent *agent,
 			struct ib_umad_packet *packet)
 {
 	int ret = 1;
 
-	down_read(&file->agent_mutex);
-	for (packet->mad.id = 0;
-	     packet->mad.id < IB_UMAD_MAX_AGENTS;
-	     packet->mad.id++)
-		if (agent == file->agent[packet->mad.id]) {
+	down_read(&file->port->mutex);
+
+	for (packet->mad.hdr.id = 0;
+	     packet->mad.hdr.id < IB_UMAD_MAX_AGENTS;
+	     packet->mad.hdr.id++)
+		if (agent == __get_agent(file, packet->mad.hdr.id)) {
 			spin_lock_irq(&file->recv_lock);
 			list_add_tail(&packet->list, &file->recv_list);
 			spin_unlock_irq(&file->recv_lock);
@@ -126,7 +172,7 @@ static int queue_packet(struct ib_umad_file *file,
 			break;
 		}
 
-	up_read(&file->agent_mutex);
+	up_read(&file->port->mutex);
 
 	return ret;
 }
@@ -135,22 +181,17 @@ static void send_handler(struct ib_mad_agent *agent,
 			 struct ib_mad_send_wc *send_wc)
 {
 	struct ib_umad_file *file = agent->context;
-	struct ib_umad_packet *packet =
-		(void *) (unsigned long) send_wc->wr_id;
+	struct ib_umad_packet *packet = send_wc->send_buf->context[0];
 
-	dma_unmap_single(agent->device->dma_device,
-			 pci_unmap_addr(packet, mapping),
-			 sizeof packet->mad.data,
-			 DMA_TO_DEVICE);
-	ib_destroy_ah(packet->ah);
+	ib_destroy_ah(packet->msg->ah);
+	ib_free_send_mad(packet->msg);
 
 	if (send_wc->status == IB_WC_RESP_TIMEOUT_ERR) {
-		packet->mad.status = ETIMEDOUT;
-
+		packet->length = IB_MGMT_MAD_HDR;
+		packet->mad.hdr.status = ETIMEDOUT;
 		if (!queue_packet(file, agent, packet))
 			return;
 	}
-
 	kfree(packet);
 }
 
@@ -161,37 +202,106 @@ static void recv_handler(struct ib_mad_agent *agent,
 	struct ib_umad_packet *packet;
 
 	if (mad_recv_wc->wc->status != IB_WC_SUCCESS)
-		goto out;
+		goto err1;
 
-	packet = kmalloc(sizeof *packet, GFP_KERNEL);
+	packet = kzalloc(sizeof *packet, GFP_KERNEL);
 	if (!packet)
-		goto out;
-
-	memset(packet, 0, sizeof *packet);
-
-	memcpy(packet->mad.data, mad_recv_wc->recv_buf.mad, sizeof packet->mad.data);
-	packet->mad.status        = 0;
-	packet->mad.qpn 	  = cpu_to_be32(mad_recv_wc->wc->src_qp);
-	packet->mad.lid 	  = cpu_to_be16(mad_recv_wc->wc->slid);
-	packet->mad.sl  	  = mad_recv_wc->wc->sl;
-	packet->mad.path_bits 	  = mad_recv_wc->wc->dlid_path_bits;
-	packet->mad.grh_present   = !!(mad_recv_wc->wc->wc_flags & IB_WC_GRH);
-	if (packet->mad.grh_present) {
+		goto err1;
+
+	packet->length = mad_recv_wc->mad_len;
+	packet->recv_wc = mad_recv_wc;
+
+	packet->mad.hdr.status    = 0;
+	packet->mad.hdr.length    = sizeof (struct ib_user_mad) +
+				    mad_recv_wc->mad_len;
+	packet->mad.hdr.qpn 	  = cpu_to_be32(mad_recv_wc->wc->src_qp);
+	packet->mad.hdr.lid 	  = cpu_to_be16(mad_recv_wc->wc->slid);
+	packet->mad.hdr.sl  	  = mad_recv_wc->wc->sl;
+	packet->mad.hdr.path_bits = mad_recv_wc->wc->dlid_path_bits;
+	packet->mad.hdr.grh_present = !!(mad_recv_wc->wc->wc_flags & IB_WC_GRH);
+	if (packet->mad.hdr.grh_present) {
 		/* XXX parse GRH */
-		packet->mad.gid_index 	  = 0;
-		packet->mad.hop_limit 	  = 0;
-		packet->mad.traffic_class = 0;
-		memset(packet->mad.gid, 0, 16);
-		packet->mad.flow_label 	  = 0;
+		packet->mad.hdr.gid_index 	= 0;
+		packet->mad.hdr.hop_limit 	= 0;
+		packet->mad.hdr.traffic_class	= 0;
+		memset(packet->mad.hdr.gid, 0, 16);
+		packet->mad.hdr.flow_label	= 0;
 	}
 
 	if (queue_packet(file, agent, packet))
-		kfree(packet);
+		goto err2;
+	return;
 
-out:
+err2:
+	kfree(packet);
+err1:
 	ib_free_recv_mad(mad_recv_wc);
 }
 
+static ssize_t copy_recv_mad(char __user *buf, struct ib_umad_packet *packet,
+			     size_t count)
+{
+	struct ib_mad_recv_buf *recv_buf;
+	int left, seg_payload, offset, max_seg_payload;
+
+	/* We need enough room to copy the first (or only) MAD segment. */
+	recv_buf = &packet->recv_wc->recv_buf;
+	if ((packet->length <= sizeof (*recv_buf->mad) &&
+	     count < sizeof (packet->mad) + packet->length) ||
+	    (packet->length > sizeof (*recv_buf->mad) &&
+	     count < sizeof (packet->mad) + sizeof (*recv_buf->mad)))
+		return -EINVAL;
+
+	if (copy_to_user(buf, &packet->mad, sizeof (packet->mad)))
+		return -EFAULT;
+
+	buf += sizeof (packet->mad);
+	seg_payload = min_t(int, packet->length, sizeof (*recv_buf->mad));
+	if (copy_to_user(buf, recv_buf->mad, seg_payload))
+		return -EFAULT;
+
+	if (seg_payload < packet->length) {
+		/*
+		 * Multipacket RMPP MAD message. Copy remainder of message.
+		 * Note that last segment may have a shorter payload.
+		 */
+		if (count < sizeof (packet->mad) + packet->length) {
+			/*
+			 * The buffer is too small, return the first RMPP segment,
+			 * which includes the RMPP message length.
+			 */
+			return -ENOSPC;
+		}
+		offset = ib_get_mad_data_offset(recv_buf->mad->mad_hdr.mgmt_class);
+		max_seg_payload = sizeof (struct ib_mad) - offset;
+
+		for (left = packet->length - seg_payload, buf += seg_payload;
+		     left; left -= seg_payload, buf += seg_payload) {
+			recv_buf = container_of(recv_buf->list.next,
+						struct ib_mad_recv_buf, list);
+			seg_payload = min(left, max_seg_payload);
+			if (copy_to_user(buf, ((void *) recv_buf->mad) + offset,
+					 seg_payload))
+				return -EFAULT;
+		}
+	}
+	return sizeof (packet->mad) + packet->length;
+}
+
+static ssize_t copy_send_mad(char __user *buf, struct ib_umad_packet *packet,
+			     size_t count)
+{
+	ssize_t size = sizeof (packet->mad) + packet->length;
+
+	if (count < size)
+		return -EINVAL;
+
+	if (copy_to_user(buf, &packet->mad, size))
+		return -EFAULT;
+
+	return size;
+}
+
 static ssize_t ib_umad_read(struct file *filp, char __user *buf,
 			    size_t count, loff_t *pos)
 {
@@ -222,15 +332,44 @@ static ssize_t ib_umad_read(struct file *filp, char __user *buf,
 
 	spin_unlock_irq(&file->recv_lock);
 
-	if (copy_to_user(buf, &packet->mad, sizeof packet->mad))
-		ret = -EFAULT;
+	if (packet->recv_wc)
+		ret = copy_recv_mad(buf, packet, count);
 	else
-		ret = sizeof packet->mad;
+		ret = copy_send_mad(buf, packet, count);
 
-	kfree(packet);
+	if (ret < 0) {
+		/* Requeue packet */
+		spin_lock_irq(&file->recv_lock);
+		list_add(&packet->list, &file->recv_list);
+		spin_unlock_irq(&file->recv_lock);
+	} else {
+		if (packet->recv_wc)
+			ib_free_recv_mad(packet->recv_wc);
+		kfree(packet);
+	}
 	return ret;
 }
 
+static int copy_rmpp_mad(struct ib_mad_send_buf *msg, const char __user *buf)
+{
+	int left, seg;
+
+	/* Copy class specific header */
+	if ((msg->hdr_len > IB_MGMT_RMPP_HDR) &&
+	    copy_from_user(msg->mad + IB_MGMT_RMPP_HDR, buf + IB_MGMT_RMPP_HDR,
+			   msg->hdr_len - IB_MGMT_RMPP_HDR))
+		return -EFAULT;
+
+	/* All headers are in place.  Copy data segments. */
+	for (seg = 1, left = msg->data_len, buf += msg->hdr_len; left > 0;
+	     seg++, left -= msg->seg_size, buf += msg->seg_size) {
+		if (copy_from_user(ib_get_rmpp_segment(msg, seg), buf,
+				   min(left, msg->seg_size)))
+			return -EFAULT;
+	}
+	return 0;
+}
+
 static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
 			     size_t count, loff_t *pos)
 {
@@ -238,109 +377,130 @@ static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
 	struct ib_umad_packet *packet;
 	struct ib_mad_agent *agent;
 	struct ib_ah_attr ah_attr;
-	struct ib_sge      gather_list;
-	struct ib_send_wr *bad_wr, wr = {
-		.opcode      = IB_WR_SEND,
-		.sg_list     = &gather_list,
-		.num_sge     = 1,
-		.send_flags  = IB_SEND_SIGNALED,
-	};
+	struct ib_ah *ah;
+	struct ib_rmpp_mad *rmpp_mad;
 	u8 method;
-	u64 *tid;
-	int ret;
+	__be64 *tid;
+	int ret, data_len, hdr_len, copy_offset, rmpp_active;
 
-	if (count < sizeof (struct ib_user_mad))
+	if (count < sizeof (struct ib_user_mad) + IB_MGMT_RMPP_HDR)
 		return -EINVAL;
 
-	packet = kmalloc(sizeof *packet, GFP_KERNEL);
+	packet = kzalloc(sizeof *packet + IB_MGMT_RMPP_HDR, GFP_KERNEL);
 	if (!packet)
 		return -ENOMEM;
 
-	if (copy_from_user(&packet->mad, buf, sizeof packet->mad)) {
-		kfree(packet);
-		return -EFAULT;
+	if (copy_from_user(&packet->mad, buf,
+			    sizeof (struct ib_user_mad) + IB_MGMT_RMPP_HDR)) {
+		ret = -EFAULT;
+		goto err;
 	}
 
-	if (packet->mad.id < 0 || packet->mad.id >= IB_UMAD_MAX_AGENTS) {
+	if (packet->mad.hdr.id < 0 ||
+	    packet->mad.hdr.id >= IB_UMAD_MAX_AGENTS) {
 		ret = -EINVAL;
 		goto err;
 	}
 
-	down_read(&file->agent_mutex);
+	down_read(&file->port->mutex);
 
-	agent = file->agent[packet->mad.id];
+	agent = __get_agent(file, packet->mad.hdr.id);
 	if (!agent) {
 		ret = -EINVAL;
 		goto err_up;
 	}
 
+	memset(&ah_attr, 0, sizeof ah_attr);
+	ah_attr.dlid          = be16_to_cpu(packet->mad.hdr.lid);
+	ah_attr.sl            = packet->mad.hdr.sl;
+	ah_attr.src_path_bits = packet->mad.hdr.path_bits;
+	ah_attr.port_num      = file->port->port_num;
+	if (packet->mad.hdr.grh_present) {
+		ah_attr.ah_flags = IB_AH_GRH;
+		memcpy(ah_attr.grh.dgid.raw, packet->mad.hdr.gid, 16);
+		ah_attr.grh.flow_label 	   = be32_to_cpu(packet->mad.hdr.flow_label);
+		ah_attr.grh.hop_limit  	   = packet->mad.hdr.hop_limit;
+		ah_attr.grh.traffic_class  = packet->mad.hdr.traffic_class;
+	}
+
+	ah = ib_create_ah(agent->qp->pd, &ah_attr);
+	if (IS_ERR(ah)) {
+		ret = PTR_ERR(ah);
+		goto err_up;
+	}
+
+	rmpp_mad = (struct ib_rmpp_mad *) packet->mad.data;
+	hdr_len = ib_get_mad_data_offset(rmpp_mad->mad_hdr.mgmt_class);
+	if (!ib_is_mad_class_rmpp(rmpp_mad->mad_hdr.mgmt_class)) {
+		copy_offset = IB_MGMT_MAD_HDR;
+		rmpp_active = 0;
+	} else {
+		copy_offset = IB_MGMT_RMPP_HDR;
+		rmpp_active = ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
+			      IB_MGMT_RMPP_FLAG_ACTIVE;
+	}
+
+	data_len = count - sizeof (struct ib_user_mad) - hdr_len;
+	packet->msg = ib_create_send_mad(agent,
+					 be32_to_cpu(packet->mad.hdr.qpn),
+					 0, rmpp_active, hdr_len,
+					 data_len, GFP_KERNEL);
+	if (IS_ERR(packet->msg)) {
+		ret = PTR_ERR(packet->msg);
+		goto err_ah;
+	}
+
+	packet->msg->ah 	= ah;
+	packet->msg->timeout_ms = packet->mad.hdr.timeout_ms;
+	packet->msg->retries 	= packet->mad.hdr.retries;
+	packet->msg->context[0] = packet;
+
+	/* Copy MAD header.  Any RMPP header is already in place. */
+	memcpy(packet->msg->mad, packet->mad.data, IB_MGMT_MAD_HDR);
+	buf += sizeof (struct ib_user_mad);
+
+	if (!rmpp_active) {
+		if (copy_from_user(packet->msg->mad + copy_offset,
+				   buf + copy_offset,
+				   hdr_len + data_len - copy_offset)) {
+			ret = -EFAULT;
+			goto err_msg;
+		}
+	} else {
+		ret = copy_rmpp_mad(packet->msg, buf);
+		if (ret)
+			goto err_msg;
+	}
+
 	/*
 	 * If userspace is generating a request that will generate a
 	 * response, we need to make sure the high-order part of the
 	 * transaction ID matches the agent being used to send the
 	 * MAD.
 	 */
-	method = ((struct ib_mad_hdr *) packet->mad.data)->method;
+	method = ((struct ib_mad_hdr *) packet->msg->mad)->method;
 
 	if (!(method & IB_MGMT_METHOD_RESP)       &&
 	    method != IB_MGMT_METHOD_TRAP_REPRESS &&
 	    method != IB_MGMT_METHOD_SEND) {
-		tid = &((struct ib_mad_hdr *) packet->mad.data)->tid;
+		tid = &((struct ib_mad_hdr *) packet->msg->mad)->tid;
 		*tid = cpu_to_be64(((u64) agent->hi_tid) << 32 |
 				   (be64_to_cpup(tid) & 0xffffffff));
 	}
 
-	memset(&ah_attr, 0, sizeof ah_attr);
-	ah_attr.dlid          = be16_to_cpu(packet->mad.lid);
-	ah_attr.sl            = packet->mad.sl;
-	ah_attr.src_path_bits = packet->mad.path_bits;
-	ah_attr.port_num      = file->port->port_num;
-	if (packet->mad.grh_present) {
-		ah_attr.ah_flags = IB_AH_GRH;
-		memcpy(ah_attr.grh.dgid.raw, packet->mad.gid, 16);
-		ah_attr.grh.flow_label 	   = packet->mad.flow_label;
-		ah_attr.grh.hop_limit  	   = packet->mad.hop_limit;
-		ah_attr.grh.traffic_class  = packet->mad.traffic_class;
-	}
+	ret = ib_post_send_mad(packet->msg, NULL);
+	if (ret)
+		goto err_msg;
 
-	packet->ah = ib_create_ah(agent->qp->pd, &ah_attr);
-	if (IS_ERR(packet->ah)) {
-		ret = PTR_ERR(packet->ah);
-		goto err_up;
-	}
-
-	gather_list.addr = dma_map_single(agent->device->dma_device,
-					  packet->mad.data,
-					  sizeof packet->mad.data,
-					  DMA_TO_DEVICE);
-	gather_list.length = sizeof packet->mad.data;
-	gather_list.lkey   = file->mr[packet->mad.id]->lkey;
-	pci_unmap_addr_set(packet, mapping, gather_list.addr);
-
-	wr.wr.ud.mad_hdr     = (struct ib_mad_hdr *) packet->mad.data;
-	wr.wr.ud.ah          = packet->ah;
-	wr.wr.ud.remote_qpn  = be32_to_cpu(packet->mad.qpn);
-	wr.wr.ud.remote_qkey = be32_to_cpu(packet->mad.qkey);
-	wr.wr.ud.timeout_ms  = packet->mad.timeout_ms;
-
-	wr.wr_id            = (unsigned long) packet;
-
-	ret = ib_post_send_mad(agent, &wr, &bad_wr);
-	if (ret) {
-		dma_unmap_single(agent->device->dma_device,
-				 pci_unmap_addr(packet, mapping),
-				 sizeof packet->mad.data,
-				 DMA_TO_DEVICE);
-		goto err_up;
-	}
-
-	up_read(&file->agent_mutex);
-
-	return sizeof packet->mad;
+	up_read(&file->port->mutex);
+	return count;
 
+err_msg:
+	ib_free_send_mad(packet->msg);
+err_ah:
+	ib_destroy_ah(ah);
 err_up:
-	up_read(&file->agent_mutex);
-
+	up_read(&file->port->mutex);
 err:
 	kfree(packet);
 	return ret;
@@ -369,7 +529,12 @@ static int ib_umad_reg_agent(struct ib_umad_file *file, unsigned long arg)
 	int agent_id;
 	int ret;
 
-	down_write(&file->agent_mutex);
+	down_write(&file->port->mutex);
+
+	if (!file->port->ib_dev) {
+		ret = -EPIPE;
+		goto out;
+	}
 
 	if (copy_from_user(&ureq, (void __user *) arg, sizeof ureq)) {
 		ret = -EFAULT;
@@ -382,7 +547,7 @@ static int ib_umad_reg_agent(struct ib_umad_file *file, unsigned long arg)
 	}
 
 	for (agent_id = 0; agent_id < IB_UMAD_MAX_AGENTS; ++agent_id)
-		if (!file->agent[agent_id])
+		if (!__get_agent(file, agent_id))
 			goto found;
 
 	ret = -ENOMEM;
@@ -399,69 +564,58 @@ found:
 	agent = ib_register_mad_agent(file->port->ib_dev, file->port->port_num,
 				      ureq.qpn ? IB_QPT_GSI : IB_QPT_SMI,
 				      ureq.mgmt_class ? &req : NULL,
-				      0, send_handler, recv_handler, file);
+				      ureq.rmpp_version,
+				      send_handler, recv_handler, file);
 	if (IS_ERR(agent)) {
 		ret = PTR_ERR(agent);
 		goto out;
 	}
 
-	file->agent[agent_id] = agent;
-
-	file->mr[agent_id] = ib_get_dma_mr(agent->qp->pd, IB_ACCESS_LOCAL_WRITE);
-	if (IS_ERR(file->mr[agent_id])) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
 	if (put_user(agent_id,
 		     (u32 __user *) (arg + offsetof(struct ib_user_mad_reg_req, id)))) {
 		ret = -EFAULT;
-		goto err_mr;
+		ib_unregister_mad_agent(agent);
+		goto out;
 	}
 
+	file->agent[agent_id] = agent;
 	ret = 0;
-	goto out;
-
-err_mr:
-	ib_dereg_mr(file->mr[agent_id]);
-
-err:
-	file->agent[agent_id] = NULL;
-	ib_unregister_mad_agent(agent);
 
 out:
-	up_write(&file->agent_mutex);
+	up_write(&file->port->mutex);
 	return ret;
 }
 
 static int ib_umad_unreg_agent(struct ib_umad_file *file, unsigned long arg)
 {
+	struct ib_mad_agent *agent = NULL;
 	u32 id;
 	int ret = 0;
 
-	down_write(&file->agent_mutex);
+	if (get_user(id, (u32 __user *) arg))
+		return -EFAULT;
 
-	if (get_user(id, (u32 __user *) arg)) {
-		ret = -EFAULT;
-		goto out;
-	}
+	down_write(&file->port->mutex);
 
-	if (id < 0 || id >= IB_UMAD_MAX_AGENTS || !file->agent[id]) {
+	if (id < 0 || id >= IB_UMAD_MAX_AGENTS || !__get_agent(file, id)) {
 		ret = -EINVAL;
 		goto out;
 	}
 
-	ib_dereg_mr(file->mr[id]);
-	ib_unregister_mad_agent(file->agent[id]);
+	agent = file->agent[id];
 	file->agent[id] = NULL;
 
 out:
-	up_write(&file->agent_mutex);
+	up_write(&file->port->mutex);
+
+	if (agent)
+		ib_unregister_mad_agent(agent);
+
 	return ret;
 }
 
-static long ib_umad_ioctl(struct file *filp,
-			 unsigned int cmd, unsigned long arg)
+static long ib_umad_ioctl(struct file *filp, unsigned int cmd,
+			  unsigned long arg)
 {
 	switch (cmd) {
 	case IB_USER_MAD_REGISTER_AGENT:
@@ -475,84 +629,136 @@ static long ib_umad_ioctl(struct file *filp,
 
 static int ib_umad_open(struct inode *inode, struct file *filp)
 {
-	struct ib_umad_port *port =
-		container_of(inode->i_cdev, struct ib_umad_port, dev);
+	struct ib_umad_port *port;
 	struct ib_umad_file *file;
+	int ret = 0;
 
-	file = kmalloc(sizeof *file, GFP_KERNEL);
-	if (!file)
-		return -ENOMEM;
+	spin_lock(&port_lock);
+	port = umad_port[iminor(inode) - IB_UMAD_MINOR_BASE];
+	if (port)
+		kref_get(&port->umad_dev->ref);
+	spin_unlock(&port_lock);
 
-	memset(file, 0, sizeof *file);
+	if (!port)
+		return -ENXIO;
+
+	down_write(&port->mutex);
+
+	if (!port->ib_dev) {
+		ret = -ENXIO;
+		goto out;
+	}
+
+	file = kzalloc(sizeof *file, GFP_KERNEL);
+	if (!file) {
+		kref_put(&port->umad_dev->ref, ib_umad_release_dev);
+		ret = -ENOMEM;
+		goto out;
+	}
 
 	spin_lock_init(&file->recv_lock);
-	init_rwsem(&file->agent_mutex);
 	INIT_LIST_HEAD(&file->recv_list);
 	init_waitqueue_head(&file->recv_wait);
 
 	file->port = port;
 	filp->private_data = file;
 
-	return 0;
+	list_add_tail(&file->port_list, &port->file_list);
+
+out:
+	up_write(&port->mutex);
+	return ret;
 }
 
 static int ib_umad_close(struct inode *inode, struct file *filp)
 {
 	struct ib_umad_file *file = filp->private_data;
+	struct ib_umad_device *dev = file->port->umad_dev;
 	struct ib_umad_packet *packet, *tmp;
+	int already_dead;
 	int i;
 
-	for (i = 0; i < IB_UMAD_MAX_AGENTS; ++i)
-		if (file->agent[i]) {
-			ib_dereg_mr(file->mr[i]);
-			ib_unregister_mad_agent(file->agent[i]);
-		}
+	down_write(&file->port->mutex);
+
+	already_dead = file->agents_dead;
+	file->agents_dead = 1;
 
-	list_for_each_entry_safe(packet, tmp, &file->recv_list, list)
+	list_for_each_entry_safe(packet, tmp, &file->recv_list, list) {
+		if (packet->recv_wc)
+			ib_free_recv_mad(packet->recv_wc);
 		kfree(packet);
+	}
+
+	list_del(&file->port_list);
+
+	downgrade_write(&file->port->mutex);
+
+	if (!already_dead)
+		for (i = 0; i < IB_UMAD_MAX_AGENTS; ++i)
+			if (file->agent[i])
+				ib_unregister_mad_agent(file->agent[i]);
+
+	up_read(&file->port->mutex);
 
 	kfree(file);
+	kref_put(&dev->ref, ib_umad_release_dev);
 
 	return 0;
 }
 
 static struct file_operations umad_fops = {
-	.owner 	        = THIS_MODULE,
-	.read 	        = ib_umad_read,
-	.write 	        = ib_umad_write,
-	.poll 	        = ib_umad_poll,
+	.owner 	 	= THIS_MODULE,
+	.read 	 	= ib_umad_read,
+	.write 	 	= ib_umad_write,
+	.poll 	 	= ib_umad_poll,
 	.unlocked_ioctl = ib_umad_ioctl,
-	.compat_ioctl   = ib_umad_ioctl,
-	.open 	        = ib_umad_open,
-	.release        = ib_umad_close
+	.compat_ioctl 	= ib_umad_ioctl,
+	.open 	 	= ib_umad_open,
+	.release 	= ib_umad_close
 };
 
 static int ib_umad_sm_open(struct inode *inode, struct file *filp)
 {
-	struct ib_umad_port *port =
-		container_of(inode->i_cdev, struct ib_umad_port, sm_dev);
+	struct ib_umad_port *port;
 	struct ib_port_modify props = {
 		.set_port_cap_mask = IB_PORT_SM
 	};
 	int ret;
 
+	spin_lock(&port_lock);
+	port = umad_port[iminor(inode) - IB_UMAD_MINOR_BASE - IB_UMAD_MAX_PORTS];
+	if (port)
+		kref_get(&port->umad_dev->ref);
+	spin_unlock(&port_lock);
+
+	if (!port)
+		return -ENXIO;
+
 	if (filp->f_flags & O_NONBLOCK) {
-		if (down_trylock(&port->sm_sem))
-			return -EAGAIN;
+		if (down_trylock(&port->sm_sem)) {
+			ret = -EAGAIN;
+			goto fail;
+		}
 	} else {
-		if (down_interruptible(&port->sm_sem))
-			return -ERESTARTSYS;
+		if (down_interruptible(&port->sm_sem)) {
+			ret = -ERESTARTSYS;
+			goto fail;
+		}
 	}
 
 	ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
 	if (ret) {
 		up(&port->sm_sem);
-		return ret;
+		goto fail;
 	}
 
 	filp->private_data = port;
 
 	return 0;
+
+fail:
+	kref_put(&port->umad_dev->ref, ib_umad_release_dev);
+	return ret;
 }
 
 static int ib_umad_sm_close(struct inode *inode, struct file *filp)
@@ -561,11 +767,17 @@ static int ib_umad_sm_close(struct inode *inode, struct file *filp)
 	struct ib_port_modify props = {
 		.clr_port_cap_mask = IB_PORT_SM
 	};
-	int ret;
+	int ret = 0;
+
+	down_write(&port->mutex);
+	if (port->ib_dev)
+		ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
+	up_write(&port->mutex);
 
-	ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
 	up(&port->sm_sem);
 
+	kref_put(&port->umad_dev->ref, ib_umad_release_dev);
+
 	return ret;
 }
 
@@ -581,21 +793,13 @@ static struct ib_client umad_client = {
 	.remove = ib_umad_remove_one
 };
 
-static ssize_t show_dev(struct class_device *class_dev, char *buf)
-{
-	struct ib_umad_port *port = class_get_devdata(class_dev);
-
-	if (class_dev == &port->class_dev)
-		return print_dev_t(buf, port->dev.dev);
-	else
-		return print_dev_t(buf, port->sm_dev.dev);
-}
-static CLASS_DEVICE_ATTR(dev, S_IRUGO, show_dev, NULL);
-
 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
 {
 	struct ib_umad_port *port = class_get_devdata(class_dev);
 
+	if (!port)
+		return -ENODEV;
+
 	return sprintf(buf, "%s\n", port->ib_dev->name);
 }
 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
@@ -604,38 +808,13 @@ static ssize_t show_port(struct class_device *class_dev, char *buf)
 {
 	struct ib_umad_port *port = class_get_devdata(class_dev);
 
+	if (!port)
+		return -ENODEV;
+
 	return sprintf(buf, "%d\n", port->port_num);
 }
 static CLASS_DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
 
-static void ib_umad_release_dev(struct kref *ref)
-{
-	struct ib_umad_device *dev =
-		container_of(ref, struct ib_umad_device, ref);
-
-	kfree(dev);
-}
-
-static void ib_umad_release_port(struct class_device *class_dev)
-{
-	struct ib_umad_port *port = class_get_devdata(class_dev);
-
-	if (class_dev == &port->class_dev) {
-		cdev_del(&port->dev);
-		clear_bit(port->devnum, dev_map);
-	} else {
-		cdev_del(&port->sm_dev);
-		clear_bit(port->sm_devnum, dev_map);
-	}
-
-	kref_put(&port->umad_dev->ref, ib_umad_release_dev);
-}
-
-static struct class umad_class = {
-	.name    = "infiniband_mad",
-	.release = ib_umad_release_port
-};
-
 static ssize_t show_abi_version(struct class *class, char *buf)
 {
 	return sprintf(buf, "%d\n", IB_USER_MAD_ABI_VERSION);
@@ -645,91 +824,144 @@ static CLASS_ATTR(abi_version, S_IRUGO, show_abi_version, NULL);
 static int ib_umad_init_port(struct ib_device *device, int port_num,
 			     struct ib_umad_port *port)
 {
-	spin_lock(&map_lock);
-	port->devnum = find_first_zero_bit(dev_map, IB_UMAD_MAX_PORTS);
-	if (port->devnum >= IB_UMAD_MAX_PORTS) {
-		spin_unlock(&map_lock);
+	spin_lock(&port_lock);
+	port->dev_num = find_first_zero_bit(dev_map, IB_UMAD_MAX_PORTS);
+	if (port->dev_num >= IB_UMAD_MAX_PORTS) {
+		spin_unlock(&port_lock);
 		return -1;
 	}
-	port->sm_devnum = find_next_zero_bit(dev_map, IB_UMAD_MAX_PORTS * 2, IB_UMAD_MAX_PORTS);
-	if (port->sm_devnum >= IB_UMAD_MAX_PORTS * 2) {
-		spin_unlock(&map_lock);
-		return -1;
-	}
-	set_bit(port->devnum, dev_map);
-	set_bit(port->sm_devnum, dev_map);
-	spin_unlock(&map_lock);
+	set_bit(port->dev_num, dev_map);
+	spin_unlock(&port_lock);
 
 	port->ib_dev   = device;
 	port->port_num = port_num;
 	init_MUTEX(&port->sm_sem);
+	init_rwsem(&port->mutex);
+	INIT_LIST_HEAD(&port->file_list);
 
-	cdev_init(&port->dev, &umad_fops);
-	port->dev.owner = THIS_MODULE;
-	kobject_set_name(&port->dev.kobj, "umad%d", port->devnum);
-	if (cdev_add(&port->dev, base_dev + port->devnum, 1))
+	port->dev = cdev_alloc();
+	if (!port->dev)
 		return -1;
-
-	port->class_dev.class = &umad_class;
-	port->class_dev.dev   = device->dma_device;
-
-	snprintf(port->class_dev.class_id, BUS_ID_SIZE, "umad%d", port->devnum);
-
-	if (class_device_register(&port->class_dev))
+	port->dev->owner = THIS_MODULE;
+	port->dev->ops   = &umad_fops;
+	kobject_set_name(&port->dev->kobj, "umad%d", port->dev_num);
+	if (cdev_add(port->dev, base_dev + port->dev_num, 1))
 		goto err_cdev;
 
-	class_set_devdata(&port->class_dev, port);
-	kref_get(&port->umad_dev->ref);
+	port->class_dev = class_device_create(umad_class, NULL, port->dev->dev,
+					      device->dma_device,
+					      "umad%d", port->dev_num);
+	if (IS_ERR(port->class_dev))
+		goto err_cdev;
 
-	if (class_device_create_file(&port->class_dev, &class_device_attr_dev))
-		goto err_class;
-	if (class_device_create_file(&port->class_dev, &class_device_attr_ibdev))
+	if (class_device_create_file(port->class_dev, &class_device_attr_ibdev))
 		goto err_class;
-	if (class_device_create_file(&port->class_dev, &class_device_attr_port))
+	if (class_device_create_file(port->class_dev, &class_device_attr_port))
 		goto err_class;
 
-	cdev_init(&port->sm_dev, &umad_sm_fops);
-	port->sm_dev.owner = THIS_MODULE;
-	kobject_set_name(&port->dev.kobj, "issm%d", port->sm_devnum - IB_UMAD_MAX_PORTS);
-	if (cdev_add(&port->sm_dev, base_dev + port->sm_devnum, 1))
-		return -1;
-
-	port->sm_class_dev.class = &umad_class;
-	port->sm_class_dev.dev   = device->dma_device;
-
-	snprintf(port->sm_class_dev.class_id, BUS_ID_SIZE, "issm%d", port->sm_devnum - IB_UMAD_MAX_PORTS);
+	port->sm_dev = cdev_alloc();
+	if (!port->sm_dev)
+		goto err_class;
+	port->sm_dev->owner = THIS_MODULE;
+	port->sm_dev->ops   = &umad_sm_fops;
+	kobject_set_name(&port->sm_dev->kobj, "issm%d", port->dev_num);
+	if (cdev_add(port->sm_dev, base_dev + port->dev_num + IB_UMAD_MAX_PORTS, 1))
+		goto err_sm_cdev;
 
-	if (class_device_register(&port->sm_class_dev))
+	port->sm_class_dev = class_device_create(umad_class, NULL, port->sm_dev->dev,
+						 device->dma_device,
+						 "issm%d", port->dev_num);
+	if (IS_ERR(port->sm_class_dev))
 		goto err_sm_cdev;
 
-	class_set_devdata(&port->sm_class_dev, port);
-	kref_get(&port->umad_dev->ref);
+	class_set_devdata(port->class_dev,    port);
+	class_set_devdata(port->sm_class_dev, port);
 
-	if (class_device_create_file(&port->sm_class_dev, &class_device_attr_dev))
+	if (class_device_create_file(port->sm_class_dev, &class_device_attr_ibdev))
 		goto err_sm_class;
-	if (class_device_create_file(&port->sm_class_dev, &class_device_attr_ibdev))
-		goto err_sm_class;
-	if (class_device_create_file(&port->sm_class_dev, &class_device_attr_port))
+	if (class_device_create_file(port->sm_class_dev, &class_device_attr_port))
 		goto err_sm_class;
 
+	spin_lock(&port_lock);
+	umad_port[port->dev_num] = port;
+	spin_unlock(&port_lock);
+
 	return 0;
 
 err_sm_class:
-	class_device_unregister(&port->sm_class_dev);
+	class_device_destroy(umad_class, port->sm_dev->dev);
 
 err_sm_cdev:
-	cdev_del(&port->sm_dev);
+	cdev_del(port->sm_dev);
 
 err_class:
-	class_device_unregister(&port->class_dev);
+	class_device_destroy(umad_class, port->dev->dev);
 
 err_cdev:
-	cdev_del(&port->dev);
-	clear_bit(port->devnum, dev_map);
+	cdev_del(port->dev);
+	clear_bit(port->dev_num, dev_map);
 
 	return -1;
 }
 
+static void ib_umad_kill_port(struct ib_umad_port *port)
+{
+	struct ib_umad_file *file;
+	int id;
+
+	class_set_devdata(port->class_dev,    NULL);
+	class_set_devdata(port->sm_class_dev, NULL);
+
+	class_device_destroy(umad_class, port->dev->dev);
+	class_device_destroy(umad_class, port->sm_dev->dev);
+
+	cdev_del(port->dev);
+	cdev_del(port->sm_dev);
+
+	spin_lock(&port_lock);
+	umad_port[port->dev_num] = NULL;
+	spin_unlock(&port_lock);
+
+	down_write(&port->mutex);
+
+	port->ib_dev = NULL;
+
+	/*
+	 * Now go through the list of files attached to this port and
+	 * unregister all of their MAD agents.  We need to hold
+	 * port->mutex while doing this to avoid racing with
+	 * ib_umad_close(), but we can't hold the mutex for writing
+	 * while calling ib_unregister_mad_agent(), since that might
+	 * deadlock by calling back into queue_packet().  So we
+	 * downgrade our lock to a read lock, and then drop and
+	 * reacquire the write lock for the next iteration.
+	 *
+	 * We do list_del_init() on the file's list_head so that the
+	 * list_del in ib_umad_close() is still OK, even after the
+	 * file is removed from the list.
+	 */
+	while (!list_empty(&port->file_list)) {
+		file = list_entry(port->file_list.next, struct ib_umad_file,
+				  port_list);
+
+		file->agents_dead = 1;
+		list_del_init(&file->port_list);
+
+		downgrade_write(&port->mutex);
+
+		for (id = 0; id < IB_UMAD_MAX_AGENTS; ++id)
+			if (file->agent[id])
+				ib_unregister_mad_agent(file->agent[id]);
+
+		up_read(&port->mutex);
+		down_write(&port->mutex);
+	}
+
+	up_write(&port->mutex);
+
+	clear_bit(port->dev_num, dev_map);
+}
+
 static void ib_umad_add_one(struct ib_device *device)
 {
 	struct ib_umad_device *umad_dev;
@@ -742,15 +974,12 @@ static void ib_umad_add_one(struct ib_device *device)
 		e = device->phys_port_cnt;
 	}
 
-	umad_dev = kmalloc(sizeof *umad_dev +
+	umad_dev = kzalloc(sizeof *umad_dev +
 			   (e - s + 1) * sizeof (struct ib_umad_port),
 			   GFP_KERNEL);
 	if (!umad_dev)
 		return;
 
-	memset(umad_dev, 0, sizeof *umad_dev +
-	       (e - s + 1) * sizeof (struct ib_umad_port));
-
 	kref_init(&umad_dev->ref);
 
 	umad_dev->start_port = s;
@@ -768,10 +997,8 @@ static void ib_umad_add_one(struct ib_device *device)
 	return;
 
 err:
-	while (--i >= s) {
-		class_device_unregister(&umad_dev->port[i - s].class_dev);
-		class_device_unregister(&umad_dev->port[i - s].sm_class_dev);
-	}
+	while (--i >= s)
+		ib_umad_kill_port(&umad_dev->port[i - s]);
 
 	kref_put(&umad_dev->ref, ib_umad_release_dev);
 }
@@ -784,10 +1011,8 @@ static void ib_umad_remove_one(struct ib_device *device)
 	if (!umad_dev)
 		return;
 
-	for (i = 0; i <= umad_dev->end_port - umad_dev->start_port; ++i) {
-		class_device_unregister(&umad_dev->port[i].class_dev);
-		class_device_unregister(&umad_dev->port[i].sm_class_dev);
-	}
+	for (i = 0; i <= umad_dev->end_port - umad_dev->start_port; ++i)
+		ib_umad_kill_port(&umad_dev->port[i]);
 
 	kref_put(&umad_dev->ref, ib_umad_release_dev);
 }
@@ -796,8 +1021,6 @@ static int __init ib_umad_init(void)
 {
 	int ret;
 
-	spin_lock_init(&map_lock);
-
 	ret = register_chrdev_region(base_dev, IB_UMAD_MAX_PORTS * 2,
 				     "infiniband_mad");
 	if (ret) {
@@ -805,13 +1028,14 @@ static int __init ib_umad_init(void)
 		goto out;
 	}
 
-	ret = class_register(&umad_class);
-	if (ret) {
+	umad_class = class_create(THIS_MODULE, "infiniband_mad");
+	if (IS_ERR(umad_class)) {
+		ret = PTR_ERR(umad_class);
 		printk(KERN_ERR "user_mad: couldn't create class infiniband_mad\n");
 		goto out_chrdev;
 	}
 
-	ret = class_create_file(&umad_class, &class_attr_abi_version);
+	ret = class_create_file(umad_class, &class_attr_abi_version);
 	if (ret) {
 		printk(KERN_ERR "user_mad: couldn't create abi_version attribute\n");
 		goto out_class;
@@ -826,7 +1050,7 @@ static int __init ib_umad_init(void)
 	return 0;
 
 out_class:
-	class_unregister(&umad_class);
+	class_destroy(umad_class);
 
 out_chrdev:
 	unregister_chrdev_region(base_dev, IB_UMAD_MAX_PORTS * 2);
@@ -838,7 +1062,7 @@ out:
 static void __exit ib_umad_cleanup(void)
 {
 	ib_unregister_client(&umad_client);
-	class_unregister(&umad_class);
+	class_destroy(umad_class);
 	unregister_chrdev_region(base_dev, IB_UMAD_MAX_PORTS * 2);
 }