From 71c42157904404a37f89fff3b2536c55115823a5 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 23 Jun 2007 17:16:42 -0700 Subject: document nlink function These should have been documented from the beginning. Fix it. Signed-off-by: Dave Hansen Cc: Al Viro Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/fs.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'include/linux/fs.h') diff --git a/include/linux/fs.h b/include/linux/fs.h index b3ae77cccbb6..6a41f4cab14c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1211,6 +1211,14 @@ static inline void mark_inode_dirty_sync(struct inode *inode) __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++; @@ -1222,11 +1230,30 @@ static inline void inode_inc_link_count(struct inode *inode) 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; -- cgit v1.2.3-59-g8ed1b