[PATCH 5/4] xfs: fix nfs export of 64-bit inodes numbers on 32-bit kernels

[Christoph Hellwig]

The i_ino field in the VFS inode is of type unsigned long and thus can't
hold the full 64-bit inode number on 32-bit kernels.  We have the full
inode number in the XFS inode, so use that one for nfs exports.  Note
that I've also switched the 32-bit file handles types to it, just to make
the code more consistent and copy & paste errors less likely to happen.

Reported-by: Guoquan Yang <ygq51 at hotmail.com>
Reported-by: Hank Peng <pengxihan at gmail.com>
Signed-off-by: Christoph Hellwig <hch at lst.de>

Index: xfs/fs/xfs/xfs_export.c
===================================================================
--- xfs.orig/fs/xfs/xfs_export.c	2011-11-28 12:11:08.923630697 +0100
+++ xfs/fs/xfs/xfs_export.c	2011-11-29 05:48:12.682177223 +0100
@@ -98,22 +98,22 @@ xfs_fs_encode_fh(
 	switch (fileid_type) {
 	case FILEID_INO32_GEN_PARENT:
 		spin_lock(&dentry->d_lock);
-		fid->i32.parent_ino = dentry->d_parent->d_inode->i_ino;
+		fid->i32.parent_ino = XFS_I(dentry->d_parent->d_inode)->i_ino;
 		fid->i32.parent_gen = dentry->d_parent->d_inode->i_generation;
 		spin_unlock(&dentry->d_lock);
 		/*FALLTHRU*/
 	case FILEID_INO32_GEN:
-		fid->i32.ino = inode->i_ino;
+		fid->i32.ino = XFS_I(inode)->i_ino;
 		fid->i32.gen = inode->i_generation;
 		break;
 	case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
 		spin_lock(&dentry->d_lock);
-		fid64->parent_ino = dentry->d_parent->d_inode->i_ino;
+		fid64->parent_ino = XFS_I(dentry->d_parent->d_inode)->i_ino;
 		fid64->parent_gen = dentry->d_parent->d_inode->i_generation;
 		spin_unlock(&dentry->d_lock);
 		/*FALLTHRU*/
 	case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
-		fid64->ino = inode->i_ino;
+		fid64->ino = XFS_I(inode)->i_ino;
 		fid64->gen = inode->i_generation;
 		break;
 	}