ftdev: remove event activation hack

Instead of doing the hackisch 'write commands to device' thing,
let's  just use a real ioctl() interface.

1 files changed, 21 insertions, 38 deletions

diff --git a/litmus/ftdev.c b/litmus/ftdev.c
index 4a4b2e3e56c2..216dc0b4cb94 100644
--- a/litmus/ftdev.c
+++ b/litmus/ftdev.c
@@ -250,64 +250,47 @@ out:
         return err;
 }
 
-typedef uint32_t cmd_t;
-
-static ssize_t ftdev_write(struct file *filp, const char __user *from,
-                           size_t len, loff_t *f_pos)
+static long ftdev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
+        long err = -ENOIOCTLCMD;
         struct ftdev_minor* ftdm = filp->private_data;
-        ssize_t err = -EINVAL;
-        cmd_t cmd;
-        cmd_t id;
-
-        if (len % sizeof(cmd) || len < 2 * sizeof(cmd))
-                goto out;
-
-        if (copy_from_user(&cmd, from, sizeof(cmd))) {
-                err = -EFAULT;
-                goto out;
-        }
-        len  -= sizeof(cmd);
-        from += sizeof(cmd);
-
-        if (cmd != FTDEV_ENABLE_CMD && cmd != FTDEV_DISABLE_CMD)
-                goto out;
 
         if (mutex_lock_interruptible(&ftdm->lock)) {
                 err = -ERESTARTSYS;
                 goto out;
         }
 
-        err = sizeof(cmd);
-        while (len) {
-                if (copy_from_user(&id, from, sizeof(cmd))) {
-                        err = -EFAULT;
-                        goto out_unlock;
-                }
-                /* FIXME: check id against list of acceptable events */
-                len  -= sizeof(cmd);
-                from += sizeof(cmd);
-                if (cmd == FTDEV_DISABLE_CMD)
-                        deactivate(&ftdm->events, id);
-                else if (activate(&ftdm->events, id) != 0) {
+        /* FIXME: check id against list of acceptable events */
+
+        switch (cmd) {
+        case  FTDEV_ENABLE_CMD:
+                if (activate(&ftdm->events, arg))
                         err = -ENOMEM;
-                        goto out_unlock;
-                }
-                err += sizeof(cmd);
-        }
+                else
+                        err = 0;
+                break;
+
+        case FTDEV_DISABLE_CMD:
+                deactivate(&ftdm->events, arg);
+                err = 0;
+                break;
+
+        default:
+                printk(KERN_DEBUG "ftdev: strange ioctl (%u, %lu)\n", cmd, arg);
+        };
 
-out_unlock:
         mutex_unlock(&ftdm->lock);
 out:
         return err;
 }
 
+
 struct file_operations ftdev_fops = {
         .owner   = THIS_MODULE,
         .open    = ftdev_open,
         .release = ftdev_release,
-        .write   = ftdev_write,
         .read    = ftdev_read,
+        .unlocked_ioctl = ftdev_ioctl,
 };
 
 int ftdev_init( struct ftdev* ftdev, struct module* owner,