Linux-2.6.12-rc2

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / infiniband / core / user_mad.c

/*
 * 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: user_mad.c 1389 2004-12-27 22:56:47Z roland $
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/cdev.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/poll.h>
#include <linux/rwsem.h>
#include <linux/kref.h>

#include <asm/uaccess.h>
#include <asm/semaphore.h>

#include <ib_mad.h>
#include <ib_user_mad.h>

MODULE_AUTHOR("Roland Dreier");
MODULE_DESCRIPTION("InfiniBand userspace MAD packet access");
MODULE_LICENSE("Dual BSD/GPL");

enum {
        IB_UMAD_MAX_PORTS  = 64,
        IB_UMAD_MAX_AGENTS = 32,

        IB_UMAD_MAJOR      = 231,
        IB_UMAD_MINOR_BASE = 0
};

struct ib_umad_port {
        int                    devnum;
        struct cdev            dev;
        struct class_device    class_dev;

        int                    sm_devnum;
        struct cdev            sm_dev;
        struct class_device    sm_class_dev;
        struct semaphore       sm_sem;

        struct ib_device      *ib_dev;
        struct ib_umad_device *umad_dev;
        u8                     port_num;
};

struct ib_umad_device {
        int                  start_port, end_port;
        struct kref          ref;
        struct ib_umad_port  port[0];
};

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_packet {
        struct ib_user_mad mad;
        struct ib_ah      *ah;
        struct list_head   list;
        DECLARE_PCI_UNMAP_ADDR(mapping)
};

static const dev_t base_dev = MKDEV(IB_UMAD_MAJOR, IB_UMAD_MINOR_BASE);
static spinlock_t map_lock;
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 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]) {
                        spin_lock_irq(&file->recv_lock);
                        list_add_tail(&packet->list, &file->recv_list);
                        spin_unlock_irq(&file->recv_lock);
                        wake_up_interruptible(&file->recv_wait);
                        ret = 0;
                        break;
                }

        up_read(&file->agent_mutex);

        return ret;
}

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;

        dma_unmap_single(agent->device->dma_device,
                         pci_unmap_addr(packet, mapping),
                         sizeof packet->mad.data,
                         DMA_TO_DEVICE);
        ib_destroy_ah(packet->ah);

        if (send_wc->status == IB_WC_RESP_TIMEOUT_ERR) {
                packet->mad.status = ETIMEDOUT;

                if (!queue_packet(file, agent, packet))
                        return;
        }

        kfree(packet);
}

static void recv_handler(struct ib_mad_agent *agent,
                         struct ib_mad_recv_wc *mad_recv_wc)
{
        struct ib_umad_file *file = agent->context;
        struct ib_umad_packet *packet;

        if (mad_recv_wc->wc->status != IB_WC_SUCCESS)
                goto out;

        packet = kmalloc(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) {
                /* 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;
        }

        if (queue_packet(file, agent, packet))
                kfree(packet);

out:
        ib_free_recv_mad(mad_recv_wc);
}

static ssize_t ib_umad_read(struct file *filp, char __user *buf,
                            size_t count, loff_t *pos)
{
        struct ib_umad_file *file = filp->private_data;
        struct ib_umad_packet *packet;
        ssize_t ret;

        if (count < sizeof (struct ib_user_mad))
                return -EINVAL;

        spin_lock_irq(&file->recv_lock);

        while (list_empty(&file->recv_list)) {
                spin_unlock_irq(&file->recv_lock);

                if (filp->f_flags & O_NONBLOCK)
                        return -EAGAIN;

                if (wait_event_interruptible(file->recv_wait,
                                             !list_empty(&file->recv_list)))
                        return -ERESTARTSYS;

                spin_lock_irq(&file->recv_lock);
        }

        packet = list_entry(file->recv_list.next, struct ib_umad_packet, list);
        list_del(&packet->list);

        spin_unlock_irq(&file->recv_lock);

        if (copy_to_user(buf, &packet->mad, sizeof packet->mad))
                ret = -EFAULT;
        else
                ret = sizeof packet->mad;

        kfree(packet);
        return ret;
}

static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
                             size_t count, loff_t *pos)
{
        struct ib_umad_file *file = filp->private_data;
        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,
        };
        u8 method;
        u64 *tid;
        int ret;

        if (count < sizeof (struct ib_user_mad))
                return -EINVAL;

        packet = kmalloc(sizeof *packet, GFP_KERNEL);
        if (!packet)
                return -ENOMEM;

        if (copy_from_user(&packet->mad, buf, sizeof packet->mad)) {
                kfree(packet);
                return -EFAULT;
        }

        if (packet->mad.id < 0 || packet->mad.id >= IB_UMAD_MAX_AGENTS) {
                ret = -EINVAL;
                goto err;
        }

        down_read(&file->agent_mutex);

        agent = file->agent[packet->mad.id];
        if (!agent) {
                ret = -EINVAL;
                goto err_up;
        }

        /*
         * 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;

        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 = 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;
        }

        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;

err_up:
        up_read(&file->agent_mutex);

err:
        kfree(packet);
        return ret;
}

static unsigned int ib_umad_poll(struct file *filp, struct poll_table_struct *wait)
{
        struct ib_umad_file *file = filp->private_data;

        /* we will always be able to post a MAD send */
        unsigned int mask = POLLOUT | POLLWRNORM;

        poll_wait(filp, &file->recv_wait, wait);

        if (!list_empty(&file->recv_list))
                mask |= POLLIN | POLLRDNORM;

        return mask;
}

static int ib_umad_reg_agent(struct ib_umad_file *file, unsigned long arg)
{
        struct ib_user_mad_reg_req ureq;
        struct ib_mad_reg_req req;
        struct ib_mad_agent *agent;
        int agent_id;
        int ret;

        down_write(&file->agent_mutex);

        if (copy_from_user(&ureq, (void __user *) arg, sizeof ureq)) {
                ret = -EFAULT;
                goto out;
        }

        if (ureq.qpn != 0 && ureq.qpn != 1) {
                ret = -EINVAL;
                goto out;
        }

        for (agent_id = 0; agent_id < IB_UMAD_MAX_AGENTS; ++agent_id)
                if (!file->agent[agent_id])
                        goto found;

        ret = -ENOMEM;
        goto out;

found:
        req.mgmt_class         = ureq.mgmt_class;
        req.mgmt_class_version = ureq.mgmt_class_version;
        memcpy(req.method_mask, ureq.method_mask, sizeof req.method_mask);
        memcpy(req.oui,         ureq.oui,         sizeof req.oui);

        agent = ib_register_mad_agent(file->port->ib_dev, file->port->port_num,
                                      ureq.qpn ? IB_QPT_GSI : IB_QPT_SMI,
                                      &req, 0, 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;
        }

        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);
        return ret;
}

static int ib_umad_unreg_agent(struct ib_umad_file *file, unsigned long arg)
{
        u32 id;
        int ret = 0;

        down_write(&file->agent_mutex);

        if (get_user(id, (u32 __user *) arg)) {
                ret = -EFAULT;
                goto out;
        }

        if (id < 0 || id >= IB_UMAD_MAX_AGENTS || !file->agent[id]) {
                ret = -EINVAL;
                goto out;
        }

        ib_dereg_mr(file->mr[id]);
        ib_unregister_mad_agent(file->agent[id]);
        file->agent[id] = NULL;

out:
        up_write(&file->agent_mutex);
        return ret;
}

static long ib_umad_ioctl(struct file *filp,
                         unsigned int cmd, unsigned long arg)
{
        switch (cmd) {
        case IB_USER_MAD_REGISTER_AGENT:
                return ib_umad_reg_agent(filp->private_data, arg);
        case IB_USER_MAD_UNREGISTER_AGENT:
                return ib_umad_unreg_agent(filp->private_data, arg);
        default:
                return -ENOIOCTLCMD;
        }
}

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_file *file;

        file = kmalloc(sizeof *file, GFP_KERNEL);
        if (!file)
                return -ENOMEM;

        memset(file, 0, sizeof *file);

        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;
}

static int ib_umad_close(struct inode *inode, struct file *filp)
{
        struct ib_umad_file *file = filp->private_data;
        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]);
                }

        kfree(file);

        return 0;
}

static struct file_operations umad_fops = {
        .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
};

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_port_modify props = {
                .set_port_cap_mask = IB_PORT_SM
        };
        int ret;

        if (filp->f_flags & O_NONBLOCK) {
                if (down_trylock(&port->sm_sem))
                        return -EAGAIN;
        } else {
                if (down_interruptible(&port->sm_sem))
                        return -ERESTARTSYS;
        }

        ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
        if (ret) {
                up(&port->sm_sem);
                return ret;
        }

        filp->private_data = port;

        return 0;
}

static int ib_umad_sm_close(struct inode *inode, struct file *filp)
{
        struct ib_umad_port *port = filp->private_data;
        struct ib_port_modify props = {
                .clr_port_cap_mask = IB_PORT_SM
        };
        int ret;

        ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
        up(&port->sm_sem);

        return ret;
}

static struct file_operations umad_sm_fops = {
        .owner   = THIS_MODULE,
        .open    = ib_umad_sm_open,
        .release = ib_umad_sm_close
};

static struct ib_client umad_client = {
        .name   = "umad",
        .add    = ib_umad_add_one,
        .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);

        return sprintf(buf, "%s\n", port->ib_dev->name);
}
static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);

static ssize_t show_port(struct class_device *class_dev, char *buf)
{
        struct ib_umad_port *port = class_get_devdata(class_dev);

        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);
}
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);
                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);

        port->ib_dev   = device;
        port->port_num = port_num;
        init_MUTEX(&port->sm_sem);

        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))
                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))
                goto err_cdev;

        class_set_devdata(&port->class_dev, port);
        kref_get(&port->umad_dev->ref);

        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))
                goto err_class;
        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);

        if (class_device_register(&port->sm_class_dev))
                goto err_sm_cdev;

        class_set_devdata(&port->sm_class_dev, port);
        kref_get(&port->umad_dev->ref);

        if (class_device_create_file(&port->sm_class_dev, &class_device_attr_dev))
                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))
                goto err_sm_class;

        return 0;

err_sm_class:
        class_device_unregister(&port->sm_class_dev);

err_sm_cdev:
        cdev_del(&port->sm_dev);

err_class:
        class_device_unregister(&port->class_dev);

err_cdev:
        cdev_del(&port->dev);
        clear_bit(port->devnum, dev_map);

        return -1;
}

static void ib_umad_add_one(struct ib_device *device)
{
        struct ib_umad_device *umad_dev;
        int s, e, i;

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

        umad_dev = kmalloc(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;
        umad_dev->end_port   = e;

        for (i = s; i <= e; ++i) {
                umad_dev->port[i - s].umad_dev = umad_dev;

                if (ib_umad_init_port(device, i, &umad_dev->port[i - s]))
                        goto err;
        }

        ib_set_client_data(device, &umad_client, umad_dev);

        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);
        }

        kref_put(&umad_dev->ref, ib_umad_release_dev);
}

static void ib_umad_remove_one(struct ib_device *device)
{
        struct ib_umad_device *umad_dev = ib_get_client_data(device, &umad_client);
        int i;

        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);
        }

        kref_put(&umad_dev->ref, ib_umad_release_dev);
}

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) {
                printk(KERN_ERR "user_mad: couldn't register device number\n");
                goto out;
        }

        ret = class_register(&umad_class);
        if (ret) {
                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);
        if (ret) {
                printk(KERN_ERR "user_mad: couldn't create abi_version attribute\n");
                goto out_class;
        }

        ret = ib_register_client(&umad_client);
        if (ret) {
                printk(KERN_ERR "user_mad: couldn't register ib_umad client\n");
                goto out_class;
        }

        return 0;

out_class:
        class_unregister(&umad_class);

out_chrdev:
        unregister_chrdev_region(base_dev, IB_UMAD_MAX_PORTS * 2);

out:
        return ret;
}

static void __exit ib_umad_cleanup(void)
{
        ib_unregister_client(&umad_client);
        class_unregister(&umad_class);
        unregister_chrdev_region(base_dev, IB_UMAD_MAX_PORTS * 2);
}

module_init(ib_umad_init);
module_exit(ib_umad_cleanup);