fuse: add fusectl interface to max_background

Make the max_background and congestion_threshold parameters of a FUSE
mount tunable at runtime by adding the respective knobs to its directory
within the fusectl filesystem.

Signed-off-by: Csaba Henk <csaba@gluster.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index e54ddbd..8f9aca8 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -31,7 +31,7 @@
 
 static int set_global_limit(const char *val, struct kernel_param *kp);
 
-static unsigned max_user_bgreq;
+unsigned max_user_bgreq;
 module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
 		  &max_user_bgreq, 0644);
 __MODULE_PARM_TYPE(max_user_bgreq, "uint");
@@ -39,7 +39,7 @@
  "Global limit for the maximum number of backgrounded requests an "
  "unprivileged user can set");
 
-static unsigned max_user_congthresh;
+unsigned max_user_congthresh;
 module_param_call(max_user_congthresh, set_global_limit, param_get_uint,
 		  &max_user_congthresh, 0644);
 __MODULE_PARM_TYPE(max_user_congthresh, "uint");