[PATCH] fuse: use jiffies_64

It is entirely possible (though rare) that jiffies half-wraps around, while a
dentry/inode remains in the cache.  This could mean that the dentry/inode is
not invalidated for another half wraparound-time.

To get around this problem, use 64-bit jiffies.  The only problem with this is
that dentry->d_time is 32 bits on 32-bit archs.  So use d_fsdata as the high
32 bits.  This is an ugly hack, but far simpler, than having to allocate
private data just for this purpose.

Since 64-bit jiffies can be assumed never to wrap around, simple comparison
can be used, and a zero time value can represent "invalid".

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/fuse/inode.c

@@ -51,7 +51,7 @@ static struct inode *fuse_alloc_inode(struct super_block *sb)
 		return NULL;
 
 	fi = get_fuse_inode(inode);
-	fi->i_time = jiffies - 1;
+	fi->i_time = 0;
 	fi->nodeid = 0;
 	fi->nlookup = 0;
 	fi->forget_req = fuse_request_alloc();