From 0eeca28300df110bd6ed54b31193c83b87921443 Mon Sep 17 00:00:00 2001 From: Robert Love Date: Tue, 12 Jul 2005 17:06:03 -0400 Subject: [PATCH] inotify inotify is intended to correct the deficiencies of dnotify, particularly its inability to scale and its terrible user interface: * dnotify requires the opening of one fd per each directory that you intend to watch. This quickly results in too many open files and pins removable media, preventing unmount. * dnotify is directory-based. You only learn about changes to directories. Sure, a change to a file in a directory affects the directory, but you are then forced to keep a cache of stat structures. * dnotify's interface to user-space is awful. Signals? inotify provides a more usable, simple, powerful solution to file change notification: * inotify's interface is a system call that returns a fd, not SIGIO. You get a single fd, which is select()-able. * inotify has an event that says "the filesystem that the item you were watching is on was unmounted." * inotify can watch directories or files. Inotify is currently used by Beagle (a desktop search infrastructure), Gamin (a FAM replacement), and other projects. See Documentation/filesystems/inotify.txt. Signed-off-by: Robert Love Cc: John McCutchan Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/inode.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'fs/inode.c') diff --git a/fs/inode.c b/fs/inode.c index 5bc97507eea..96364fae084 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -21,6 +21,7 @@ #include #include #include +#include /* * This is needed for the following functions: @@ -202,6 +203,10 @@ void inode_init_once(struct inode *inode) INIT_LIST_HEAD(&inode->i_data.i_mmap_nonlinear); spin_lock_init(&inode->i_lock); i_size_ordered_init(inode); +#ifdef CONFIG_INOTIFY + INIT_LIST_HEAD(&inode->inotify_watches); + sema_init(&inode->inotify_sem, 1); +#endif } EXPORT_SYMBOL(inode_init_once); @@ -351,6 +356,7 @@ int invalidate_inodes(struct super_block * sb) down(&iprune_sem); spin_lock(&inode_lock); + inotify_unmount_inodes(&sb->s_inodes); busy = invalidate_list(&sb->s_inodes, &throw_away); spin_unlock(&inode_lock); -- cgit v1.2.3