Add support for newers kernels, remove the temporary IOCTL and set back the writev function.

.gitattributes

@@ -0,0 +1 @@
+* ident=true

.gitignore

@@ -0,0 +1,23 @@
+# Ignore all generated files
+*.o
+*.ko
+*.cmd
+*.a
+*.d
+*.mod
+*.mod.c
+*.order
+*.so*
+*~
+
+# Generated demo executables
+examples/console-read
+examples/drums
+examples/drums2
+examples/drums3
+examples/echo
+examples/helloworld
+examples/ioctl
+examples/logring
+examples/pager
+examples/uid-filter

Makefile

@@ -6,10 +6,10 @@ PREFIX = /usr/local
 LIBDIR = $(PREFIX)/lib
 INCDIR = $(PREFIX)/include
 
-CC      = gcc 
+CC      = $(CROSS_COMPILE)gcc 
-LD      = gcc
+LD      = $(CROSS_COMPILE)gcc
 INSTALL = install
-STRIP   = strip
+STRIP   = $(CROSS_COMPILE)strip
 PREFIX  = /usr/local
 BINDIR  = $(PREFIX)/bin
 ETCDIR  = /etc/$(TARGET)

README.markdown

@@ -2,13 +2,20 @@
 FUSD: A Linux Framework for User-Space Devices
 ----------------------------------------------
 
-Welcome to FUSD!
+**Welcome to FUSD!**
 
-This is FUSD snapshot 20070111, released 11 January 2007.  You can get
+This is FUSD snapshot 20110401, released 18 January 2012. This fork is based
-the most recent source, along with online documentation, from xiph.org
+on the found on the xiph.org SVN tracker. ( http://svn.xiph.org/trunk/fusd ) 
-SVN:
+They seems to no longuer update this tool (since 11 January 2007) and since it
+longuer compile with recent Linux kernel (at around 2.6.21) and since I need
+it in personal project, I ported it to newer version (current version is 2.6.32)
 
-http://svn.xiph.org/trunk/fusd
+Some feature are still missing missing or buggy form the Xiph version (due to
+changes on the kernel source tree), but it's completly useable.
+
+The official URL for this fork is:
+
+http://github.com/Godzil/fusd
 
 There is extensive documentation available in the 'doc' directory.
 The FUSD User Manual is available in PDF, Postscript, and HTML format.
@@ -17,7 +24,7 @@ it is fully updated, it may not cover all features that exist in the
 current version of fusd.
 
 FUSD is free and open source software, released under a BSD-style
-license.  See the file 'LICENSE' for details.
+license. See the file 'LICENSE' for details.
 
 
 QUICK START GUIDE
@@ -25,81 +32,81 @@ QUICK START GUIDE
 
 Instructions for the impatient:
 
-1- Make sure you're using a system running Linux 2.6.x with udev; this
+1. Make sure you're using a system running Linux 2.6.x with udev; this
-version of fusd is incompatable with the now-deprecated devfs.  If the
+version of fusd is incompatable with the now-deprecated devfs. If the
 kernel is a packaged version from a distribution, also verify any
 optional packages needed for building new kernel modules are also
 installed.
 
-2- 'make ; make install' builds everything including examples, then
+2. 'make ; make install' builds everything including examples, then
 installs the libraries, includes and kernel module.
 
-3- Update the udev configuration (usually in /etc/udev/rules.d/) to
+3. Update the udev configuration (usually in /etc/udev/rules.d/) to
 include the following rule:
 
-   # fusd device
+         fusd device
-   SUBSYSTEM=="fusd",                      NAME="fusd/%k"
+         SUBSYSTEM=="fusd",                      NAME="fusd/%k"
 
-After updating, restart udevd (skill udevd; udevd -d).
+    After updating, restart udevd (skill udevd; udevd -d).
 
-4- Insert the FUSD kernel module (modprobe kfusd)
+4. Insert the FUSD kernel module (`modprobe kfusd`)
 
-5- Verify the fusd devices /dev/fusd/status and /dev/fusd/control
+5. Verify the fusd devices /dev/fusd/status and /dev/fusd/control
-exist.  If the modprobe succeeds but no fusd devices appear,
+exist. If the modprobe succeeds but no fusd devices appear,
 doublecheck the udev rule config change and make sure udevd restarted
-successfully.  The kfusd kernel module must be inserted after udev has
+successfully. The kfusd kernel module must be inserted after udev has
 been correctly configured and restarted.
 
-6- Try  running the helloworld  example program (examples/helloworld).
+6. Try running the `helloworld` example program (examples/helloworld).
-When  helloworld  is  running,  'cat  /dev/helloworld'  should  return
+When helloworld is running, `cat /dev/helloworld` should return
-'Hello, world!'.
+`Hello, world!`.
 
-7- For more information, read the User's Manual in the 'doc' directory.
+7. For more information, read the User's Manual in the 'doc' directory.
 
 WHAT IS FUSD?
 =============
 
 FUSD (pronounced "fused") is a Linux framework for proxying device
 file callbacks into user-space, allowing device files to be
-implemented by daemons instead of kernel code.  Despite being
+implemented by daemons instead of kernel code. Despite being
 implemented in user-space, FUSD devices can look and act just like any
 other file under /dev which is implemented by kernel callbacks.
 
 A user-space device driver can do many of the things that kernel
 drivers can't, such as perform a long-running computation, block while
-waiting for an event, or read files from the file system.  Unlike
+waiting for an event, or read files from the file system. Unlike
 kernel drivers, a user-space device driver can use other device
 drivers--that is, access the network, talk to a serial port, get
 interactive input from the user, pop up GUI windows, or read from
-disks.  User-space drivers implemented using FUSD can be much easier to
+disks. User-space drivers implemented using FUSD can be much easier to
 debug; it is impossible for them to crash the machine, are easily
 traceable using tools such as gdb, and can be killed and restarted
-without rebooting.  FUSD drivers don't have to be in C--Perl, Python,
+without rebooting. FUSD drivers don't have to be in C--Perl, Python,
 or any other language that knows how to read from and write to a file
-descriptor can work with FUSD.  User-space drivers can be swapped out,
+descriptor can work with FUSD. User-space drivers can be swapped out,
 whereas kernel drivers lock physical memory.
 
 FUSD drivers are conceptually similar to kernel drivers: a set of
 callback functions called in response to system calls made on file
-descriptors by user programs.  FUSD's C library provides a device
+descriptors by user programs. FUSD's C library provides a device
 registration function, similar to the kernel's devfs_register_chrdev()
-function, to create new devices.  fusd_register() accepts the device
+function, to create new devices. fusd_register() accepts the device
-name and a structure full of pointers.  Those pointers are callback
+name and a structure full of pointers. Those pointers are callback
 functions which are called in response to certain user system
 calls--for example, when a process tries to open, close, read from, or
-write to the device file.  The callback functions should conform to
+write to the device file. The callback functions should conform to
-the standard definitions of POSIX system call behavior.  In many ways,
+the standard definitions of POSIX system call behavior. In many ways,
 the user-space FUSD callback functions are identical to their kernel
 counterparts.
 
 The proxying of kernel system calls that makes this kind of program
 possible is implemented by FUSD, using a combination of a kernel
-module and cooperating user-space library.  The kernel module
+module and cooperating user-space library. The kernel module
 implements a character device, /dev/fusd, which is used as a control
-channel between the two.  fusd_register() uses this channel to send a
+channel between the two. fusd_register() uses this channel to send a
 message to the FUSD kernel module, telling the name of the device the
-user wants to register.  The kernel module, in turn, registers that
+user wants to register. The kernel module, in turn, registers that
-device with the kernel proper using devfs.  devfs and the kernel don't
+device with the kernel proper using devfs. devfs and the kernel don't
 know anything unusual is happening; it appears from their point of
 view that the registered devices are simply being implemented by the
 FUSD module.
@@ -107,22 +114,22 @@ FUSD module.
 Later, when kernel makes a callback due to a system call (e.g. when
 the character device file is opened or read), the FUSD kernel module's
 callback blocks the calling process, marshals the arguments of the
-callback into a message and sends it to user-space.  Once there, the
+callback into a message and sends it to user-space. Once there, the
 library half of FUSD unmarshals it and calls whatever user-space
-callback the FUSD driver passed to fusd_register().  When that
+callback the FUSD driver passed to fusd_register(). When that
 user-space callback returns a value, the process happens in reverse:
 the return value and its side-effects are marshaled by the library
-and sent to the kernel.  The FUSD kernel module unmarshals this
+and sent to the kernel. The FUSD kernel module unmarshals this
 message, matches it up with a corresponding outstanding request, and
-completes the system call.  The calling process is completely unaware
+completes the system call. The calling process is completely unaware
 of this trickery; it simply enters the kernel once, blocks, unblocks,
 and returns from the system call---just as it would for any other
 blocking call.
 
-One of the primary design goals of FUSD is stability.  It should
+One of the primary design goals of FUSD is stability. It should
 not be possible for a FUSD driver to corrupt or crash the kernel,
-either due to error or malice.  Of course, a buggy driver itself may
+either due to error or malice. Of course, a buggy driver itself may
-corrupt itself (e.g., due to a buffer overrun).  However, strict error
+corrupt itself (e.g., due to a buffer overrun). However, strict error
 checking is implemented at the user-kernel boundary which should
 prevent drivers from corrupting the kernel or any other user-space
 process---including the errant driver's own clients, and other FUSD
@@ -131,9 +138,13 @@ drivers.
 For more information, please see the comprehensive documentation in
 the 'doc' directory.
  
- Jeremy Elson <jelson@circlemud.org>
+> Jeremy Elson <jelson@circlemud.org>                              <br>
- August 19, 2003
+> August 19, 2003                                                  <br>
 
- updated,
+> updated,<br>
- Monty <monty@xiph.org>
+> Monty <monty@xiph.org>                                           <br>
- January 11, 2007
+> January 11, 2007                                                 <br>
+
+> Updated,                                                         <br>
+> Godzil <godzil@godzil.net>                                       <br>
+> March 01, 2011 / January 18, 2012 (public release on github)

examples/console-read.c

@@ -40,7 +40,7 @@
  * need a template from which to start on a real driver, use pager.c
  * instead.
  *
- * $Id$
+ * $Id: console-read.c 12351 2007-01-19 07:22:54Z xiphmont $
  */
 
 #include <stdio.h>

examples/drums.c

@@ -42,7 +42,7 @@
  * directory: /dev/drums/bam, /dev/drums/bum, etc.  If you cat one of
  * these devices, it returns a string that's the same as its name.
  *
- * $Id$
+ * $Id: drums.c 12355 2007-01-19 17:44:17Z xiphmont $
  */
 
 #include <stdio.h>

examples/drums2.c

@@ -47,7 +47,7 @@
  * to remember if this user has read before; cat /dev/drums/X will
  * read infinitely
  *
- * $Id$
+ * $Id: drums2.c 12355 2007-01-19 17:44:17Z xiphmont $
  */
 
 #include <stdio.h>

examples/drums3.c

@@ -43,7 +43,7 @@
  * However, it also prints a prompt to the console, asking the user if
  * how loud the drums should be.
  *
- * $Id$
+ * $Id: drums3.c 12351 2007-01-19 07:22:54Z xiphmont $
  */
 
 #include <stdio.h>

examples/echo.c

@@ -41,7 +41,7 @@
  * stored.  Then, when you read (e.g. "cat /dev/echo"), you get back
  * whatever you wrote most recently.
  *
- * $Id$ 
+ * $Id: echo.c 12351 2007-01-19 07:22:54Z xiphmont $ 
  */
 
 #include <stdio.h>

examples/helloworld.c

@@ -37,7 +37,7 @@
  * hello-world: Simply creates a device called /dev/hello-world, which
  * greets you when you try to get it.
  *
- * $Id$
+ * $Id: helloworld.c 12351 2007-01-19 07:22:54Z xiphmont $
  */
 
 /* EXAMPLE START helloworld.c */

examples/ioctl.c

@@ -41,7 +41,7 @@
  * the other examples, anyway), because this program is both an
  * example and part of the regression test suite.
  *
- * $Id$ 
+ * $Id: ioctl.c 12351 2007-01-19 07:22:54Z xiphmont $ 
  */
 
 #include <stdio.h>

examples/logring.c

@@ -71,7 +71,7 @@
  * but want to use it on a system that does not have FUSD, check out
  * emlog at http://www.circlemud.org/~jelson/software/emlog.
  *
- * $Id$
+ * $Id: logring.c 12351 2007-01-19 07:22:54Z xiphmont $
  */
 
 #include <stdio.h>

examples/pager.c

@@ -60,7 +60,7 @@
  * If you close the FD and then reopen it, there will be a race (pages
  * that arrive between the close and open will not be delivered).
  *
- * $Id$
+ * $Id: pager.c 12355 2007-01-19 17:44:17Z xiphmont $
  */
 
 #include <stdio.h>

examples/uid-filter.c

@@ -42,7 +42,7 @@
  * not be read by anyone other than the driver owner (not even root!).
  * When you read from the device, it returns your PID to you.
  *
- * $Id$
+ * $Id: uid-filter.c 12351 2007-01-19 07:22:54Z xiphmont $
  */
 
 #include <stdio.h>

include/kfusd.h

@@ -37,28 +37,29 @@
  *
  * Private header file used by the Linux Kernel Module
  *
- * $Id$
+ * $Id: kfusd.h 12351 2007-01-19 07:22:54Z xiphmont $
  */
 
 #ifndef __KFUSD_H__
-#define __KFUSD_H__
+# define __KFUSD_H__
 
-#include "fusd_msg.h"
+# include "fusd_msg.h"
+# include <linux/version.h>
 
 /* magic numbers for structure checking; unique w.r.t
  * /usr/src/linux/Documentation/magic-number.txt */
-#define FUSD_DEV_MAGIC      0x8b43a123
+# define FUSD_DEV_MAGIC      0x8b43a123
-#define FUSD_FILE_MAGIC     0x613aa8fe
+# define FUSD_FILE_MAGIC     0x613aa8fe
 
 /* number of devices that can be created with fusd */
-#define MAX_FUSD_DEVICES    128
+# define MAX_FUSD_DEVICES    128
 
 /* number of times each device can be opened simultaneously */
-#define MIN_FILEARRAY_SIZE  8  /* initialize allocation */
+# define MIN_FILEARRAY_SIZE  8  /* initialize allocation */
-#define MAX_FILEARRAY_SIZE  1024 /* maximum it can grow to */
+# define MAX_FILEARRAY_SIZE  1024 /* maximum it can grow to */
 
 /* maximum read/write size we're willing to service */
-#define MAX_RW_SIZE         (1024*128)
+# define MAX_RW_SIZE         (1024*128)
 
 
 /********************** Structure Definitions *******************************/
@@ -88,7 +89,7 @@ struct fusd_transaction
 struct fusd_dev_t_s;
 typedef struct fusd_dev_t_s fusd_dev_t;
 struct CLASS;
-struct class_device;
+struct device;
 
 /* state kept per opened file (i.e., an instance of a device) */
 typedef struct {
@@ -125,8 +126,11 @@ struct fusd_dev_t_s {
   char *dev_name;
   struct CLASS *clazz;
   int owns_class;
-  struct class_device *class_device;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,29)
-  
+  struct class_device *device;
+#else
+  struct device *device;
+#endif
   void *private_data;		/* User's private data */
   struct cdev* handle;
   dev_t dev_id;
@@ -174,34 +178,34 @@ STATIC struct fusd_transaction* fusd_find_transaction_by_pid(fusd_file_t *fusd_f
 
 /**** Utility functions & macros ****/
 
-#ifdef CONFIG_FUSD_USE_WAKEUPSYNC
+# ifdef CONFIG_FUSD_USE_WAKEUPSYNC
-#define WAKE_UP_INTERRUPTIBLE_SYNC(x) wake_up_interruptible_sync(x)
+#  define WAKE_UP_INTERRUPTIBLE_SYNC(x) wake_up_interruptible_sync(x)
-#else
+# else
-#define WAKE_UP_INTERRUPTIBLE_SYNC(x) wake_up_interruptible(x)
+#  define WAKE_UP_INTERRUPTIBLE_SYNC(x) wake_up_interruptible(x)
-#endif /* CONFIG_FUSD_USE_WAKEUPSYNC */
+# endif /* CONFIG_FUSD_USE_WAKEUPSYNC */
 
-#ifdef CONFIG_FUSD_DEBUG
+# ifdef CONFIG_FUSD_DEBUG
 static void rdebug_real(char *fmt, ...)
   __attribute__ ((format (printf, 1, 2)));
 
-#define RDEBUG(message_level, args...) do { \
+#  define RDEBUG(message_level, args...) do { \
    if (fusd_debug_level >= message_level) rdebug_real(args); \
 } while(0)
-#else
+# else
-#define RDEBUG(message_level, args...)
+#  define RDEBUG(message_level, args...)
-#endif /* CONFIG_FUSD_DEBUG */
+# endif /* CONFIG_FUSD_DEBUG */
 
 
-#define ZOMBIE(fusd_dev)  ((fusd_dev)->zombie)
+# define ZOMBIE(fusd_dev)  ((fusd_dev)->zombie)
 
 
-#define GET_FUSD_DEV(candidate, fusd_dev) do { \
+# define GET_FUSD_DEV(candidate, fusd_dev) do { \
   fusd_dev = candidate; \
   if (fusd_dev == NULL || fusd_dev->magic != FUSD_DEV_MAGIC) \
         goto invalid_dev; \
 } while (0)
 
-#define GET_FUSD_FILE_AND_DEV(candidate, fusd_file, fusd_dev) do { \
+# define GET_FUSD_FILE_AND_DEV(candidate, fusd_file, fusd_dev) do { \
   fusd_file = candidate; \
   if (fusd_file == NULL || fusd_file->magic != FUSD_FILE_MAGIC) \
      goto invalid_file; \
@@ -210,36 +214,40 @@ static void rdebug_real(char *fmt, ...)
     goto invalid_file; \
 } while (0)
 
-
+#  define LOCK_FUSD_DEV(fusd_dev) \
-#define LOCK_FUSD_DEV(fusd_dev) \
   do { down(&fusd_dev->dev_sem); \
   if (ZOMBIE(fusd_dev)) { up(&fusd_dev->dev_sem); goto zombie_dev; } \
  } while (0)
 
 /* rawlock does not do a zombie check */
-#define RAWLOCK_FUSD_DEV(fusd_dev) \
+
+#  define RAWLOCK_FUSD_DEV(fusd_dev) \
   do { down(&fusd_dev->dev_sem); } while (0)
 
-#define UNLOCK_FUSD_DEV(fusd_dev) \
+#  define UNLOCK_FUSD_DEV(fusd_dev) \
   do { up(&fusd_dev->dev_sem); } while (0)
 
-
+#  define LOCK_FUSD_FILE(fusd_file) \
-#define LOCK_FUSD_FILE(fusd_file) \
   do { down(&fusd_file->file_sem); \
  } while (0)
 
-#define UNLOCK_FUSD_FILE(fusd_file) \
+#  define UNLOCK_FUSD_FILE(fusd_file) \
   do { up(&fusd_file->file_sem); } while (0)
 
-#define FREE_FUSD_MSGC(fusd_msgc) do { \
+# define FREE_FUSD_MSGC(fusd_msgc) do { \
    if ((fusd_msgc)->fusd_msg.data != NULL) VFREE(fusd_msgc->fusd_msg.data); \
    KFREE(fusd_msgc); \
 } while (0)
 
-#define NAME(fusd_dev) ((fusd_dev)->name == NULL ? \
+# define FREE_FUSD_MSGC(fusd_msgc) do { \
+   if ((fusd_msgc)->fusd_msg.data != NULL) VFREE(fusd_msgc->fusd_msg.data); \
+   KFREE(fusd_msgc); \
+} while (0)
+
+# define NAME(fusd_dev) ((fusd_dev)->name == NULL ? \
 			"<noname>" : (fusd_dev)->name)
 
-#ifdef CONFIG_FUSD_MEMDEBUG
+# ifdef CONFIG_FUSD_MEMDEBUG
 static int  fusd_mem_init(void);
 static void fusd_mem_cleanup(void);
 static void fusd_mem_add(void *ptr, int line, int size);
@@ -248,25 +256,28 @@ static void *fusd_kmalloc(size_t size, int type, int line);
 static void fusd_kfree(void *ptr);
 static void *fusd_vmalloc(size_t size, int line);
 static void fusd_vfree(void *ptr);
-# define KMALLOC(size, type) fusd_kmalloc(size, type, __LINE__)
+#  define KMALLOC(size, type) fusd_kmalloc(size, type, __LINE__)
-# define KFREE(ptr) fusd_kfree(ptr)
+#  define KFREE(ptr) fusd_kfree(ptr)
-# define VMALLOC(size) fusd_vmalloc(size, __LINE__)
+#  define VMALLOC(size) fusd_vmalloc(size, __LINE__)
-# define VFREE(ptr) fusd_vfree(ptr)
+#  define VFREE(ptr) fusd_vfree(ptr)
-#else /* no memory debugging */
+# else /* no memory debugging */
-# define KMALLOC(size, type) kmalloc(size, type)
+#  define KMALLOC(size, type) kmalloc(size, type)
-# define KFREE(ptr) kfree(ptr)
+#  define KFREE(ptr) kfree(ptr)
 /*# define VMALLOC(size) vmalloc(size)*/
-# define VMALLOC(size) kmalloc(size, GFP_KERNEL)
+#  define VMALLOC(size) kmalloc(size, GFP_KERNEL)
-# define VFREE(ptr) kfree(ptr)
+#  define VFREE(ptr) kfree(ptr)
-#endif /* CONFIG_FUSD_MEMDEBUG */
+# endif /* CONFIG_FUSD_MEMDEBUG */
 
 
 
 /* Functions like this should be in the kernel, but they are not.  Sigh. */
-#ifdef CONFIG_SMP
+# ifdef CONFIG_SMP
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,30)
 DECLARE_MUTEX(atomic_ops);
-
+#else
+DEFINE_SEMAPHORE(atomic_ops);
+#endif
 static __inline__ int atomic_inc_and_ret(int *i)
 {
   int val;
@@ -276,12 +287,11 @@ static __inline__ int atomic_inc_and_ret(int *i)
   up(&atomic_ops);
   return val;
 }
-#else
+# else
 static __inline__ int atomic_inc_and_ret(int *i)
 {
   return (++(*i));
 }
-#endif
+# endif
-
 
 #endif /* __KFUSD_H__ */

kfusd/Makefile

@@ -1,16 +1,21 @@
 ifneq ($(KERNELRELEASE),)
 obj-m := kfusd.o
+KERNEL_VER ?= $(KERNELRELEASE)
 else
 KDIR	?= /lib/modules/$(shell uname -r)/build
 PWD	:= $(shell pwd)
+ROOTFS ?=
+
+KERNEL_VER ?= 2.6.32.7
 
 default:
 	$(MAKE) -C $(KDIR) SUBDIRS=$(PWD) EXTRA_CFLAGS=-I$(PWD)/../include modules
 
 install:
-	$(INSTALL) -d -m 0755 /lib/modules/$(shell uname -r)/kernel/drivers/misc
+	install -d -m 0755 $(ROOTFS)/lib/modules/$(KERNEL_VER)/kernel/drivers/misc
-	$(INSTALL) -m 0755 kfusd.ko /lib/modules/$(shell uname -r)/kernel/drivers/misc
+	install -m 0755 kfusd.ko $(ROOTFS)/lib/modules/$(KERNEL_VER)/kernel/drivers/misc
-	/sbin/depmod -a
+
+#	/sbin/depmod -a
 
 clean:
 	rm -f .kfusd* Modules.symvers \

libfusd/libfusd.c

@@ -35,10 +35,10 @@
  *
  * authors: jelson and girod
  *
- * $Id$
+ * $Id: libfusd.c 12351 2007-01-19 07:22:54Z xiphmont $
  */
 
-char libfusd_c_id[] = "$Id$";
+char libfusd_c_id[] = "$Id: libfusd.c 12351 2007-01-19 07:22:54Z xiphmont $";
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -328,8 +328,6 @@ void fusd_fdset_add(fd_set *set, int *max)
   }
 }
 
-
-
 /*
  * fusd_dispatch_fdset: given an fd_set full of descriptors, call
  * fusd_dispatch on every descriptor in the set which is a valid FUSD
@@ -410,16 +408,21 @@ static int fusd_dispatch_one(int fd, fusd_file_operations_t *fops)
   
   /* dispatch on operation type */
   user_retval = -ENOSYS;
+  //printf("dispatch_one: subcmd: %d - ", msg->subcmd);
+  
   switch (msg->subcmd) {
   case FUSD_OPEN:
+    //printf("FUSD_OPEN\n");
     if (fops && fops->open)
       user_retval = fops->open(file);
     break;
   case FUSD_CLOSE:
+    //printf("FUSD_CLOSE\n");
     if (fops && fops->close)
       user_retval = fops->close(file);
     break;
   case FUSD_READ:
+    //printf("FUSD_READ\n");
     /* allocate a buffer and make the call */
     if (fops && fops->read) {
       if ((msg->data = malloc(msg->parm.fops_msg.length)) == NULL) {
@@ -433,11 +436,13 @@ static int fusd_dispatch_one(int fd, fusd_file_operations_t *fops)
     }
     break;
   case FUSD_WRITE:
+    //printf("FUSD_WRITE\n");
     if (fops && fops->write)
       user_retval = fops->write(file, msg->data, msg->datalen,
 				&msg->parm.fops_msg.offset);
     break;
   case FUSD_MMAP:
+    //printf("FUSD_MMAP\n");
     if (fops && fops->mmap)
     {
       user_retval = fops->mmap(file, msg->parm.fops_msg.offset, msg->parm.fops_msg.length, msg->parm.fops_msg.flags,
@@ -445,6 +450,7 @@ static int fusd_dispatch_one(int fd, fusd_file_operations_t *fops)
     }
     break;
   case FUSD_IOCTL:
+    //printf("FUSD_IOCTL\n");
     if (fops && fops->ioctl) {
       /* in the case of an ioctl read, allocate a buffer for the
        * driver to write to, IF there isn't already a buffer.  (there
@@ -466,6 +472,7 @@ static int fusd_dispatch_one(int fd, fusd_file_operations_t *fops)
     break;
     
   case FUSD_POLL_DIFF:
+     //printf("FUSD_POLL_DIFF\n");
     /* This callback requests notification when an event occurs on a file,
      * e.g. becoming readable or writable */
     if (fops && fops->poll_diff)
@@ -473,6 +480,7 @@ static int fusd_dispatch_one(int fd, fusd_file_operations_t *fops)
     break;    
   
   case FUSD_UNBLOCK:
+    //printf("FUSD_UNBLOCK\n");
     /* This callback is called when a system call is interrupted */
     if (fops && fops->unblock)
       user_retval = fops->unblock(file);    
@@ -533,6 +541,7 @@ void fusd_dispatch(int fd)
   if (!FUSD_FD_VALID(fd)) {
     errno = EBADF;
     retval = -1;
+    fprintf(stderr, "libfusd: not a valid FUSD FD\n");
     goto out;
   }
   fops = FUSD_GET_FOPS(fd);
@@ -555,7 +564,7 @@ void fusd_dispatch(int fd)
 
  out:
   if (retval < 0 && errno != EPIPE)
-    fprintf(stderr, "libfusd: fusd_dispatch error on fd %d: %m\n", fd);
+    fprintf(stderr, "libfusd: fusd_dispatch error on fd %d: [%d] %m \n", fd, retval);
 }
 
 
@@ -648,11 +657,16 @@ int fusd_return(fusd_file_info_t *file, ssize_t retval)
 
   /* send message to kernel */
   if (msg->datalen && msg->data != NULL) {
+    //printf("(msg->datalen [%d] && msg->data != NULL [%p]", msg->datalen, msg->data);
     iov[0].iov_base = msg;
     iov[0].iov_len = sizeof(fusd_msg_t);
     iov[1].iov_base = msg->data;
     iov[1].iov_len = msg->datalen;
+#if 0
     driver_retval = writev(fd, iov, 2);
+#else
+    driver_retval = ioctl(fd, 0xb16b00b5, iov);
+#endif
   }
   else {
     driver_retval = write(fd, msg, sizeof(fusd_msg_t));