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>

1 files changed, 42 insertions, 0 deletions

diff --git a/fs/qnx6/namei.c b/fs/qnx6/namei.c
new file mode 100644
index 000000000000..8a97289e04ad
--- /dev/null
+++ b/fs/qnx6/namei.c
@@ -0,0 +1,42 @@
+/*
+ * QNX6 file system, Linux implementation.
+ *
+ * Version : 1.0.0
+ *
+ * History :
+ *
+ * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
+ * 16-02-2012 pagemap extension by Al Viro
+ *
+ */
+
+#include "qnx6.h"
+
+struct dentry *qnx6_lookup(struct inode *dir, struct dentry *dentry,
+                                struct nameidata *nd)
+{
+        unsigned ino;
+        struct page *page;
+        struct inode *foundinode = NULL;
+        const char *name = dentry->d_name.name;
+        int len = dentry->d_name.len;
+
+        if (len > QNX6_LONG_NAME_MAX)
+                return ERR_PTR(-ENAMETOOLONG);
+
+        ino = qnx6_find_entry(len, dir, name, &page);
+        if (ino) {
+                foundinode = qnx6_iget(dir->i_sb, ino);
+                qnx6_put_page(page);
+                if (IS_ERR(foundinode)) {
+                        QNX6DEBUG((KERN_ERR "qnx6: lookup->iget -> "
+                                " error %ld\n", PTR_ERR(foundinode)));
+                        return ERR_CAST(foundinode);
+                }
+        } else {
+                QNX6DEBUG((KERN_INFO "qnx6_lookup: not found %s\n", name));
+                return NULL;
+        }
+        d_add(dentry, foundinode);
+        return NULL;
+}