[INFINIBAND]: Add IPoIB userspace MAD support

Add a driver that provides a character special device for each
InfiniBand port.  This device allows userspace to send and receive
MADs via write() and read() (with some control operations implemented
as ioctls).

All operations are 32/64 clean and have been tested with 32-bit
userspace running on a ppc64 kernel.
Signed-off-by: Roland Dreier <roland@topspin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/infiniband/core/Makefile

 EXTRA_CFLAGS += -Idrivers/infiniband/include
 
-obj-$(CONFIG_INFINIBAND) +=	ib_core.o ib_mad.o ib_sa.o
+obj-$(CONFIG_INFINIBAND) +=	ib_core.o ib_mad.o ib_sa.o ib_umad.o
 
 ib_core-y :=			packer.o ud_header.o verbs.o sysfs.o \
 				device.o fmr_pool.o cache.o
@@ -8,3 +8,5 @@ ib_core-y :=			packer.o ud_header.o verbs.o sysfs.o \
 ib_mad-y :=			mad.o smi.o agent.o
 
 ib_sa-y :=			sa_query.o
+
+ib_umad-y :=			user_mad.o

drivers/infiniband/include/ib_user_mad.h

+/*
+ * Copyright (c) 2004 Topspin Communications.  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.
+ *
+ * $Id: ib_user_mad.h 1389 2004-12-27 22:56:47Z roland $
+ */
+
+#ifndef IB_USER_MAD_H
+#define IB_USER_MAD_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+/*
+ * Increment this value if any changes that break userspace ABI
+ * compatibility are made.
+ */
+#define IB_USER_MAD_ABI_VERSION	2
+
+/*
+ * Make sure that all structs defined in this file remain laid out so
+ * that they pack the same way on 32-bit and 64-bit architectures (to
+ * avoid incompatibility between 32-bit userspace and 64-bit kernels).
+ */
+
+/**
+ * ib_user_mad - MAD packet
+ * @data - Contents of MAD
+ * @id - ID of agent MAD received with/to be sent with
+ * @status - 0 on successful receive, ETIMEDOUT if no response
+ *   received (transaction ID in data[] will be set to TID of original
+ *   request) (ignored on send)
+ * @timeout_ms - Milliseconds to wait for response (unset on receive)
+ * @qpn - Remote QP number received from/to be sent to
+ * @qkey - Remote Q_Key to be sent with (unset on receive)
+ * @lid - Remote lid received from/to be sent to
+ * @sl - Service level received with/to be sent with
+ * @path_bits - Local path bits received with/to be sent with
+ * @grh_present - If set, GRH was received/should be sent
+ * @gid_index - Local GID index to send with (unset on receive)
+ * @hop_limit - Hop limit in GRH
+ * @traffic_class - Traffic class in GRH
+ * @gid - Remote GID in GRH
+ * @flow_label - Flow label in GRH
+ *
+ * All multi-byte quantities are stored in network (big endian) byte order.
+ */
+struct ib_user_mad {
+	__u8	data[256];
+	__u32	id;
+	__u32	status;
+	__u32	timeout_ms;
+	__u32	qpn;
+	__u32   qkey;
+	__u16	lid;
+	__u8	sl;
+	__u8	path_bits;
+	__u8	grh_present;
+	__u8	gid_index;
+	__u8	hop_limit;
+	__u8	traffic_class;
+	__u8	gid[16];
+	__u32	flow_label;
+};
+
+/**
+ * ib_user_mad_reg_req - MAD registration request
+ * @id - Set by the kernel; used to identify agent in future requests.
+ * @qpn - Queue pair number; must be 0 or 1.
+ * @method_mask - The caller will receive unsolicited MADs for any method
+ *   where @method_mask = 1.
+ * @mgmt_class - Indicates which management class of MADs should be receive
+ *   by the caller.  This field is only required if the user wishes to
+ *   receive unsolicited MADs, otherwise it should be 0.
+ * @mgmt_class_version - Indicates which version of MADs for the given
+ *   management class to receive.
+ * @oui: Indicates IEEE OUI when mgmt_class is a vendor class
+ *   in the range from 0x30 to 0x4f. Otherwise not used.
+ */
+struct ib_user_mad_reg_req {
+	__u32	id;
+	__u32	method_mask[4];
+	__u8	qpn;
+	__u8	mgmt_class;
+	__u8	mgmt_class_version;
+	__u8    oui[3];
+};
+
+#define IB_IOCTL_MAGIC		0x1b
+
+#define IB_USER_MAD_REGISTER_AGENT	_IOWR(IB_IOCTL_MAGIC, 1, \
+					      struct ib_user_mad_reg_req)
+
+#define IB_USER_MAD_UNREGISTER_AGENT	_IOW(IB_IOCTL_MAGIC, 2, __u32)
+
+#endif /* IB_USER_MAD_H */