fs: initial qnx6fs addition

Adds support for qnx6fs readonly support to the linux kernel.

* Mount option
  The option mmi_fs can be used to mount Harman Becker/Audi MMI 3G
  HDD qnx6fs filesystems.

* Documentation
  A high level filesystem stucture description can be found in the
  Documentation/filesystems directory. (qnx6.txt)

* Additional features
  - Active (stable) superblock selection
  - Superblock checksum check (enforced)
  - Supports mount of qnx6 filesystems with to host different endianess
  - Automatic endianess detection
  - Longfilename support (with non-enfocing crc check)
  - All blocksizes (512, 1024, 2048 and 4096 supported)

Signed-off-by: Kai Bankett <chaosman@ontika.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/magic.h b/include/linux/magic.h
index 2d4beab..b7ed475 100644
--- a/include/linux/magic.h
+++ b/include/linux/magic.h
@@ -42,6 +42,7 @@
 #define OPENPROM_SUPER_MAGIC	0x9fa1
 #define PROC_SUPER_MAGIC	0x9fa0
 #define QNX4_SUPER_MAGIC	0x002f		/* qnx4 fs detection */
+#define QNX6_SUPER_MAGIC	0x68191122	/* qnx6 fs detection */
 
 #define REISERFS_SUPER_MAGIC	0x52654973	/* used by gcc */
 					/* used by file system utilities that