Defined the request argument of ioctl() as unsigned long

On linux the request argument of ioctl() is defined as an unsigned long,
but the fuse protocol squashes it into a signed int. As a consequence
the value received by ntfs-3g may appear as negative and different from
the value defined by the corresponding macro.
So define the request argument as unsigned long in ntfs-3g. It has
however to be fed as unsigned from fuse until the fuse protocol is
updated.

include/fuse-lite/fuse.h

@@ -432,6 +432,9 @@ struct fuse_operations {
 	 * non-NULL cases, the area is of _IOC_SIZE(cmd) bytes.
 	 *
 	 * Introduced in version 2.8
+	 *
+	 * Note : the unsigned long request submitted by the application        
+	 * is truncated to 32 bits, and forwarded as a signed int.
 	 */
 	int (*ioctl) (const char *, int cmd, void *arg,
 		      struct fuse_file_info *, unsigned int flags, void *data); 

include/fuse-lite/fuse_lowlevel.h

@@ -814,6 +814,9 @@ struct fuse_lowlevel_ops {
 	 *
 	 * Introduced in version 2.8
 	 *
+	 * Note : the unsigned long request submitted by the application        
+	 * is truncated to 32 bits, and forwarded as a signed int.
+	 *
 	 * Valid replies:
 	 *   fuse_reply_ioctl_retry
 	 *   fuse_reply_ioctl

include/ntfs-3g/device.h

@@ -111,7 +111,8 @@ struct ntfs_device_operations {
 			s64 offset);
 	int (*sync)(struct ntfs_device *dev);
 	int (*stat)(struct ntfs_device *dev, struct stat *buf);
-	int (*ioctl)(struct ntfs_device *dev, int request, void *argp);
+	int (*ioctl)(struct ntfs_device *dev, unsigned long request,
+			void *argp);
 };
 
 extern struct ntfs_device *ntfs_device_alloc(const char *name, const long state,

include/ntfs-3g/ioctl.h

@@ -24,7 +24,12 @@
 #ifndef IOCTL_H
 #define IOCTL_H
 
-int ntfs_ioctl(ntfs_inode *ni, int cmd, void *arg,
+/*
+ * Using an "unsigned long cmd" internally, like in <sys/ioctl.h> for Linux
+ * Note however that fuse truncates the arg to 32 bits, and that
+ * some commands (e.g. FITRIM) do not fit in a signed 32 bit field.
+ */
+int ntfs_ioctl(ntfs_inode *ni, unsigned long cmd, void *arg,
                         unsigned int flags, void *data);
 
 #endif /* IOCTL_H */

libntfs-3g/unix_io.c

@@ -369,8 +369,8 @@ static int ntfs_device_unix_io_stat(struct ntfs_device *dev, struct stat *buf)
  *
  * Returns:
  */
-static int ntfs_device_unix_io_ioctl(struct ntfs_device *dev, int request,
+static int ntfs_device_unix_io_ioctl(struct ntfs_device *dev,
-		void *argp)
+		unsigned long request, void *argp)
 {
 	return ioctl(DEV_FD(dev), request, argp);
 }

libntfs-3g/win32_io.c

@@ -1847,14 +1847,14 @@ static __inline__ int ntfs_win32_blksszget(struct ntfs_device *dev,int *argp)
 	return -1;
 }
 
-static int ntfs_device_win32_ioctl(struct ntfs_device *dev, int request,
+static int ntfs_device_win32_ioctl(struct ntfs_device *dev,
-		void *argp)
+		unsigned long request, void *argp)
 {
 #if defined(BLKGETSIZE) | defined(BLKGETSIZE64)
 	win32_fd *fd = (win32_fd *)dev->d_private;
 #endif
 
-	ntfs_log_trace("win32_ioctl(%d) called.\n", request);
+	ntfs_log_trace("win32_ioctl(0x%lx) called.\n", request);
 	switch (request) {
 #if defined(BLKGETSIZE)
 	case BLKGETSIZE:
@@ -1897,7 +1897,7 @@ static int ntfs_device_win32_ioctl(struct ntfs_device *dev, int request,
 		return 0;
 #endif
 	default:
-		ntfs_log_debug("unimplemented ioctl %d.\n", request);
+		ntfs_log_debug("unimplemented ioctl 0x%lx.\n", request);
 		errno = EOPNOTSUPP;
 		return -1;
 	}

src/lowntfs-3g.c

@@ -3036,7 +3036,14 @@ static void ntfs_fuse_ioctl(fuse_req_t req __attribute__((unused)),
 			}
 			memcpy(buf, data, in_bufsz);
 		}
-		ret = ntfs_ioctl(ni, cmd, arg, flags, buf);
+		/*
+		 * Linux defines the request argument of ioctl() to be an
+		 * unsigned long, which fuse 2.x forwards as a signed int
+		 * into which the request sometimes does not fit.
+		 * So we must expand the value and make sure it is not
+		 * sign-extended.
+		 */
+		ret = ntfs_ioctl(ni, (unsigned int)cmd, arg, flags, buf);
 		if (ntfs_inode_close (ni))
 			set_fuse_error(&ret);
 	}

src/ntfs-3g.c

@@ -2777,7 +2777,13 @@ static int ntfs_fuse_ioctl(const char *path,
 	if (!ni)
 		return -errno;
 
-	ret = ntfs_ioctl(ni, cmd, arg, flags, data);
+	/*
+	 * Linux defines the request argument of ioctl() to be an
+	 * unsigned long, which fuse 2.x forwards as a signed int into
+	 * which the request sometimes does not fit.
+	 * So we must expand the value and make sure it is not sign-extended.
+	 */
+	ret = ntfs_ioctl(ni, (unsigned int)cmd, arg, flags, data);
 
 	if (ntfs_inode_close (ni))
 		set_fuse_error(&ret);