signal/timer/event fds: anonymous inode source

This patch add an anonymous inode source, to be used for files that need
and inode only in order to create a file*. We do not care of having an
inode for each file, and we do not even care of having different names in
the associated dentries (dentry names will be same for classes of file*).
This allow code reuse, and will be used by epoll, signalfd and timerfd
(and whatever else there'll be).

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 17 insertions, 0 deletions

diff --git a/include/linux/anon_inodes.h b/include/linux/anon_inodes.h
new file mode 100644
index 000000000000..b2e1ba325b9a
--- /dev/null
+++ b/include/linux/anon_inodes.h
@@ -0,0 +1,16 @@
+/*
+ *  include/linux/anon_inodes.h
+ *
+ *  Copyright (C) 2007  Davide Libenzi <davidel@xmailserver.org>
+ *
+ */
+
+#ifndef _LINUX_ANON_INODES_H
+#define _LINUX_ANON_INODES_H
+
+int anon_inode_getfd(int *pfd, struct inode **pinode, struct file **pfile,
+                     const char *name, const struct file_operations *fops,
+                     void *priv);
+
+#endif /* _LINUX_ANON_INODES_H */
+
diff --git a/include/linux/magic.h b/include/linux/magic.h
index a9c6567fe70c..9d713c03e3da 100644
--- a/include/linux/magic.h
+++ b/include/linux/magic.h
@@ -14,6 +14,7 @@
 #define ISOFS_SUPER_MAGIC       0x9660
 #define JFFS2_SUPER_MAGIC       0x72b6
 #define KVMFS_SUPER_MAGIC       0x19700426
+#define ANON_INODE_FS_MAGIC     0x09041934
 
 #define MINIX_SUPER_MAGIC       0x137F          /* original minix fs */
 #define MINIX_SUPER_MAGIC2      0x138F          /* minix fs, 30 char names */