[patch 01/22] document nlink function

[Cedric Le Goater]

From: Dave Hansen <hansendc at us.ibm.com>

These should have been documented from the beginning.  Fix it.

Signed-off-by: Dave Hansen <hansendc at us.ibm.com>
---

---
 include/linux/fs.h |   27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

Index: 2.6.22-rc4-mm2-robindmount/include/linux/fs.h
===================================================================
--- 2.6.22-rc4-mm2-robindmount.orig/include/linux/fs.h
+++ 2.6.22-rc4-mm2-robindmount/include/linux/fs.h
@@ -1403,6 +1403,14 @@ static inline void mark_inode_dirty_sync
 	__mark_inode_dirty(inode, I_DIRTY_SYNC);
 }
 
+/**
+ * inc_nlink - directly increment an inode's link count
+ * @inode: inode
+ *
+ * This is a low-level filesystem helper to replace any
+ * direct filesystem manipulation of i_nlink.  Currently,
+ * it is only here for parity with dec_nlink().
+ */
 static inline void inc_nlink(struct inode *inode)
 {
 	inode->i_nlink++;
@@ -1414,11 +1422,30 @@ static inline void inode_inc_link_count(
 	mark_inode_dirty(inode);
 }
 
+/**
+ * drop_nlink - directly drop an inode's link count
+ * @inode: inode
+ *
+ * This is a low-level filesystem helper to replace any
+ * direct filesystem manipulation of i_nlink.  In cases
+ * where we are attempting to track writes to the
+ * filesystem, a decrement to zero means an imminent
+ * write when the file is truncated and actually unlinked
+ * on the filesystem.
+ */
 static inline void drop_nlink(struct inode *inode)
 {
 	inode->i_nlink--;
 }
 
+/**
+ * clear_nlink - directly zero an inode's link count
+ * @inode: inode
+ *
+ * This is a low-level filesystem helper to replace any
+ * direct filesystem manipulation of i_nlink.  See
+ * drop_nlink() for why we care about i_nlink hitting zero.
+ */
 static inline void clear_nlink(struct inode *inode)
 {
 	inode->i_nlink = 0;

--