1 files changed, 41 insertions, 3 deletions

diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h
index 8872fe8392d6..06178a1336ff 100644
--- a/include/linux/exportfs.h
+++ b/include/linux/exportfs.h
@@ -7,6 +7,44 @@ struct dentry;
 struct super_block;
 struct vfsmount;
 
+/*
+ * The fileid_type identifies how the file within the filesystem is encoded.
+ * In theory this is freely set and parsed by the filesystem, but we try to
+ * stick to conventions so we can share some generic code and don't confuse
+ * sniffers like ethereal/wireshark.
+ *
+ * The filesystem must not use the value '0' or '0xff'.
+ */
+enum fid_type {
+        /*
+         * The root, or export point, of the filesystem.
+         * (Never actually passed down to the filesystem.
+         */
+        FILEID_ROOT = 0,
+
+        /*
+         * 32bit inode number, 32 bit generation number.
+         */
+        FILEID_INO32_GEN = 1,
+
+        /*
+         * 32bit inode number, 32 bit generation number,
+         * 32 bit parent directory inode number.
+         */
+        FILEID_INO32_GEN_PARENT = 2,
+};
+
+struct fid {
+        union {
+                struct {
+                        u32 ino;
+                        u32 gen;
+                        u32 parent_ino;
+                        u32 parent_gen;
+                } i32;
+                __u32 raw[6];
+        };
+};
 
 /**
  * struct export_operations - for nfsd to communicate with file systems
@@ -117,9 +155,9 @@ extern struct dentry *find_exported_dentry(struct super_block *sb, void *obj,
         void *parent, int (*acceptable)(void *context, struct dentry *de),
         void *context);
 
-extern int exportfs_encode_fh(struct dentry *dentry, __u32 *fh, int *max_len,
-        int connectable);
-extern struct dentry *exportfs_decode_fh(struct vfsmount *mnt, __u32 *fh,
+extern int exportfs_encode_fh(struct dentry *dentry, struct fid *fid,
+        int *max_len, int connectable);
+extern struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid,
         int fh_len, int fileid_type, int (*acceptable)(void *, struct dentry *),
         void *context);