[PATCH 19/24] Unionfs: Helper macros/inlines

["Josef 'Jeff' Sipek" <jsipek@cs.sunysb.edu>]

From: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>

This patch contains many macros and inline functions used thoughout Unionfs.

Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: David Quigley <dquigley@fsl.cs.sunysb.edu>
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
---
 fs/unionfs/fanout.h |  177 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 177 insertions(+), 0 deletions(-)

diff --git a/fs/unionfs/fanout.h b/fs/unionfs/fanout.h
new file mode 100644
index 0000000..ab3bf2c
--- /dev/null
+++ b/fs/unionfs/fanout.h
@@ -0,0 +1,177 @@
+/*
+ * Copyright (c) 2003-2006 Erez Zadok
+ * Copyright (c) 2003-2006 Charles P. Wright
+ * Copyright (c) 2005-2006 Josef Sipek
+ * Copyright (c) 2005      Arun M. Krishnakumar
+ * Copyright (c) 2004-2006 David P. Quigley
+ * Copyright (c) 2003-2004 Mohammad Nayyer Zubair
+ * Copyright (c) 2003      Puja Gupta
+ * Copyright (c) 2003      Harikesavan Krishnan
+ * Copyright (c) 2003-2006 Stony Brook University
+ * Copyright (c) 2003-2006 The Research Foundation of State University of New York
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _FANOUT_H_
+#define _FANOUT_H_
+
+/* Inode to private data */
+static inline struct unionfs_inode_info *UNIONFS_I(const struct inode *inode)
+{
+	return container_of(inode, struct unionfs_inode_info, vfs_inode);
+}
+
+#define ibstart(ino) (UNIONFS_I(ino)->bstart)
+#define ibend(ino) (UNIONFS_I(ino)->bend)
+
+/* Superblock to private data */
+#define UNIONFS_SB(super) ((struct unionfs_sb_info *)(super)->s_fs_info)
+#define sbstart(sb) 0
+#define sbend(sb) (UNIONFS_SB(sb)->bend)
+#define sbmax(sb) (UNIONFS_SB(sb)->bend + 1)
+
+/* File to private Data */
+#define UNIONFS_F(file) ((struct unionfs_file_info *)((file)->private_data))
+#define fbstart(file) (UNIONFS_F(file)->bstart)
+#define fbend(file) (UNIONFS_F(file)->bend)
+
+/* File to lower file. */
+static inline struct file *unionfs_lower_file(const struct file *f)
+{
+	return UNIONFS_F(f)->lower_files[fbstart(f)];
+}
+
+static inline struct file *unionfs_lower_file_idx(const struct file *f, int index)
+{
+	return UNIONFS_F(f)->lower_files[index];
+}
+
+static inline void unionfs_set_lower_file_idx(struct file *f, int index, struct file *val)
+{
+	UNIONFS_F(f)->lower_files[index] = val;
+}
+
+static inline void unionfs_set_lower_file(struct file *f, struct file *val)
+{
+	UNIONFS_F(f)->lower_files[fbstart(f)] = val;
+}
+
+/* Inode to lower inode. */
+static inline struct inode *unionfs_lower_inode(const struct inode *i)
+{
+	return UNIONFS_I(i)->lower_inodes[ibstart(i)];
+}
+
+static inline struct inode *unionfs_lower_inode_idx(const struct inode *i, int index)
+{
+	return UNIONFS_I(i)->lower_inodes[index];
+}
+
+static inline void unionfs_set_lower_inode_idx(struct inode *i, int index,
+				   struct inode *val)
+{
+	UNIONFS_I(i)->lower_inodes[index] = val;
+}
+
+static inline void unionfs_set_lower_inode(struct inode *i, struct inode *val)
+{
+	UNIONFS_I(i)->lower_inodes[ibstart(i)] = val;
+}
+
+/* Superblock to lower superblock. */
+static inline struct super_block *unionfs_lower_super(const struct super_block *sb)
+{
+	return UNIONFS_SB(sb)->data[sbstart(sb)].sb;
+}
+
+static inline struct super_block *unionfs_lower_super_idx(const struct super_block *sb, int index)
+{
+	return UNIONFS_SB(sb)->data[index].sb;
+}
+
+static inline void unionfs_set_lower_super_idx(struct super_block *sb, int index,
+				   struct super_block *val)
+{
+	UNIONFS_SB(sb)->data[index].sb = val;
+}
+
+static inline void unionfs_set_lower_super(struct super_block *sb, struct super_block *val)
+{
+	UNIONFS_SB(sb)->data[sbstart(sb)].sb = val;
+}
+
+/* Branch count macros. */
+static inline int branch_count(const struct super_block *sb, int index)
+{
+	return atomic_read(&UNIONFS_SB(sb)->data[index].sbcount);
+}
+
+static inline void set_branch_count(struct super_block *sb, int index, int val)
+{
+	atomic_set(&UNIONFS_SB(sb)->data[index].sbcount, val);
+}
+
+static inline void branchget(struct super_block *sb, int index)
+{
+	atomic_inc(&UNIONFS_SB(sb)->data[index].sbcount);
+}
+
+static inline void branchput(struct super_block *sb, int index)
+{
+	atomic_dec(&UNIONFS_SB(sb)->data[index].sbcount);
+}
+
+/* Dentry macros */
+static inline struct unionfs_dentry_info *UNIONFS_D(const struct dentry *dent)
+{
+	return dent->d_fsdata;
+}
+
+#define dbstart(dent) (UNIONFS_D(dent)->bstart)
+#define set_dbstart(dent, val) do { UNIONFS_D(dent)->bstart = val; } while(0)
+#define dbend(dent) (UNIONFS_D(dent)->bend)
+#define set_dbend(dent, val) do { UNIONFS_D(dent)->bend = val; } while(0)
+#define dbopaque(dent) (UNIONFS_D(dent)->bopaque)
+#define set_dbopaque(dent, val) do { UNIONFS_D(dent)->bopaque = val; } while (0)
+
+static inline void unionfs_set_lower_dentry_idx(struct dentry *dent, int index,
+				   struct dentry *val)
+{
+	UNIONFS_D(dent)->lower_paths[index].dentry = val;
+}
+
+static inline struct dentry *unionfs_lower_dentry_idx(const struct dentry *dent, int index)
+{
+	return UNIONFS_D(dent)->lower_paths[index].dentry;
+}
+
+static inline struct dentry *unionfs_lower_dentry(const struct dentry *dent)
+{
+	return unionfs_lower_dentry_idx(dent, dbstart(dent));
+}
+
+static inline void unionfs_set_lower_mnt_idx(struct dentry *dent, int index,
+				   struct vfsmount *mnt)
+{
+	UNIONFS_D(dent)->lower_paths[index].mnt = mnt;
+}
+
+static inline struct vfsmount *unionfs_lower_mnt_idx(const struct dentry *dent, int index)
+{
+	return UNIONFS_D(dent)->lower_paths[index].mnt;
+}
+
+static inline struct vfsmount *unionfs_lower_mnt(const struct dentry *dent)
+{
+	return unionfs_lower_mnt_idx(dent,dbstart(dent));
+}
+
+/* Macros for locking a dentry. */
+#define lock_dentry(d)		down(&UNIONFS_D(d)->sem)
+#define unlock_dentry(d)	up(&UNIONFS_D(d)->sem)
+#define verify_locked(d)
+
+#endif	/* _FANOUT_H */
-- 
1.4.4.2