Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq

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

diff --git a/drivers/infiniband/core/user_mad.c b/drivers/infiniband/core/user_mad.c
index 1fc17940a765e7062476a7720f533864a3de9981..268a2d23b7c9a8e9092877ca319989891e99e90d 100644 (file)
--- a/drivers/infiniband/core/user_mad.c
+++ b/drivers/infiniband/core/user_mad.c
@@ -31,8 +31,6 @@
  * 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 5596 2006-03-03 01:00:07Z sean.hefty $
  */
 
 #include <linux/module.h>
@@ -47,7 +45,6 @@
 #include <linux/kref.h>
 #include <linux/compat.h>
 #include <linux/semaphore.h>
-#include <linux/smp_lock.h>
 
 #include <asm/uaccess.h>
 
@@ -778,23 +775,33 @@ static long ib_umad_compat_ioctl(struct file *filp, unsigned int cmd,
 }
 #endif
 
+/*
+ * ib_umad_open() does not need the BKL:
+ *
+ *  - umad_port[] accesses are protected by port_lock, the
+ *    ib_umad_port structures are properly reference counted, and
+ *    everything else is purely local to the file being created, so
+ *    races against other open calls are not a problem;
+ *  - the ioctl method does not affect any global state outside of the
+ *    file structure being operated on;
+ *  - the port is added to umad_port[] as the last part of module
+ *    initialization so the open method will either immediately run
+ *    -ENXIO, or all required initialization will be done.
+ */
 static int ib_umad_open(struct inode *inode, struct file *filp)
 {
        struct ib_umad_port *port;
        struct ib_umad_file *file;
        int ret = 0;
 
-       lock_kernel();
        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);
 
-       if (!port) {
-               unlock_kernel();
+       if (!port)
                return -ENXIO;
-       }
 
        mutex_lock(&port->file_mutex);
 
@@ -823,7 +830,6 @@ static int ib_umad_open(struct inode *inode, struct file *filp)
 
 out:
        mutex_unlock(&port->file_mutex);
-       unlock_kernel();
        return ret;
 }
 
@@ -1010,8 +1016,9 @@ static int ib_umad_init_port(struct ib_device *device, int port_num,
        if (cdev_add(port->cdev, base_dev + port->dev_num, 1))
                goto err_cdev;
 
-       port->dev = device_create(umad_class, device->dma_device,
-                                 port->cdev->dev, "umad%d", port->dev_num);
+       port->dev = device_create_drvdata(umad_class, device->dma_device,
+                                         port->cdev->dev, port,
+                                         "umad%d", port->dev_num);
        if (IS_ERR(port->dev))
                goto err_cdev;
 
@@ -1029,15 +1036,12 @@ static int ib_umad_init_port(struct ib_device *device, int port_num,
        if (cdev_add(port->sm_cdev, base_dev + port->dev_num + IB_UMAD_MAX_PORTS, 1))
                goto err_sm_cdev;
 
-       port->sm_dev = device_create(umad_class, device->dma_device,
-                                    port->sm_cdev->dev,
-                                    "issm%d", port->dev_num);
+       port->sm_dev = device_create_drvdata(umad_class, device->dma_device,
+                                            port->sm_cdev->dev, port,
+                                            "issm%d", port->dev_num);
        if (IS_ERR(port->sm_dev))
                goto err_sm_cdev;
 
-       dev_set_drvdata(port->dev,    port);
-       dev_set_drvdata(port->sm_dev, port);
-
        if (device_create_file(port->sm_dev, &dev_attr_ibdev))
                goto err_sm_dev;
        if (device_create_file(port->sm_dev, &dev_attr_port))