[IB] umad: fix hot remove of IB devices

Fix hotplug of devices for ib_umad module: when a device goes away,
kill off all MAD agents for open files associated with that device,
and make sure that the device is not touched again after ib_umad
returns from its remove_one function.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
This commit is contained in:
Roland Dreier 2005-11-03 12:01:18 -08:00
parent 87cfe32375
commit 0c99cb6d5f

View File

@ -94,6 +94,9 @@ struct ib_umad_port {
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;
@ -108,10 +111,10 @@ struct ib_umad_device {
struct ib_umad_file {
struct ib_umad_port *port;
spinlock_t recv_lock;
struct list_head recv_list;
struct list_head port_list;
spinlock_t recv_lock;
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];
};
@ -148,7 +151,7 @@ static int queue_packet(struct ib_umad_file *file,
{
int ret = 1;
down_read(&file->agent_mutex);
down_read(&file->port->mutex);
for (packet->mad.hdr.id = 0;
packet->mad.hdr.id < IB_UMAD_MAX_AGENTS;
packet->mad.hdr.id++)
@ -161,7 +164,7 @@ static int queue_packet(struct ib_umad_file *file,
break;
}
up_read(&file->agent_mutex);
up_read(&file->port->mutex);
return ret;
}
@ -322,7 +325,7 @@ static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
goto err;
}
down_read(&file->agent_mutex);
down_read(&file->port->mutex);
agent = file->agent[packet->mad.hdr.id];
if (!agent) {
@ -419,7 +422,7 @@ static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
if (ret)
goto err_msg;
up_read(&file->agent_mutex);
up_read(&file->port->mutex);
return count;
@ -430,7 +433,7 @@ static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
ib_destroy_ah(ah);
err_up:
up_read(&file->agent_mutex);
up_read(&file->port->mutex);
err:
kfree(packet);
@ -460,7 +463,12 @@ 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;
@ -522,7 +530,7 @@ static int ib_umad_reg_agent(struct ib_umad_file *file, unsigned long arg)
ib_unregister_mad_agent(agent);
out:
up_write(&file->agent_mutex);
up_write(&file->port->mutex);
return ret;
}
@ -531,7 +539,7 @@ static int ib_umad_unreg_agent(struct ib_umad_file *file, unsigned long arg)
u32 id;
int ret = 0;
down_write(&file->agent_mutex);
down_write(&file->port->mutex);
if (get_user(id, (u32 __user *) arg)) {
ret = -EFAULT;
@ -548,7 +556,7 @@ static int ib_umad_unreg_agent(struct ib_umad_file *file, unsigned long arg)
file->agent[id] = NULL;
out:
up_write(&file->agent_mutex);
up_write(&file->port->mutex);
return ret;
}
@ -569,6 +577,7 @@ static int ib_umad_open(struct inode *inode, struct file *filp)
{
struct ib_umad_port *port;
struct ib_umad_file *file;
int ret = 0;
spin_lock(&port_lock);
port = umad_port[iminor(inode) - IB_UMAD_MINOR_BASE];
@ -579,21 +588,32 @@ static int ib_umad_open(struct inode *inode, struct file *filp)
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);
return -ENOMEM;
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)
@ -603,6 +623,7 @@ static int ib_umad_close(struct inode *inode, struct file *filp)
struct ib_umad_packet *packet, *tmp;
int i;
down_write(&file->port->mutex);
for (i = 0; i < IB_UMAD_MAX_AGENTS; ++i)
if (file->agent[i]) {
ib_dereg_mr(file->mr[i]);
@ -612,6 +633,9 @@ static int ib_umad_close(struct inode *inode, struct file *filp)
list_for_each_entry_safe(packet, tmp, &file->recv_list, list)
kfree(packet);
list_del(&file->port_list);
up_write(&file->port->mutex);
kfree(file);
kref_put(&dev->ref, ib_umad_release_dev);
@ -680,9 +704,13 @@ 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);
@ -745,6 +773,8 @@ static int ib_umad_init_port(struct ib_device *device, int port_num,
port->ib_dev = device;
port->port_num = port_num;
init_MUTEX(&port->sm_sem);
init_rwsem(&port->mutex);
INIT_LIST_HEAD(&port->file_list);
port->dev = cdev_alloc();
if (!port->dev)
@ -813,6 +843,9 @@ static int ib_umad_init_port(struct ib_device *device, int port_num,
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);
@ -826,6 +859,21 @@ static void ib_umad_kill_port(struct ib_umad_port *port)
umad_port[port->dev_num] = NULL;
spin_unlock(&port_lock);
down_write(&port->mutex);
port->ib_dev = NULL;
list_for_each_entry(file, &port->file_list, port_list)
for (id = 0; id < IB_UMAD_MAX_AGENTS; ++id) {
if (!file->agent[id])
continue;
ib_dereg_mr(file->mr[id]);
ib_unregister_mad_agent(file->agent[id]);
file->agent[id] = NULL;
}
up_write(&port->mutex);
clear_bit(port->dev_num, dev_map);
}