From: Tom Zanussi Documentation update for non-relay files. Signed-off-by: Tom Zanussi Signed-off-by: Andrew Morton --- Documentation/filesystems/relayfs.txt | 23 +++++++++++++++++++++++ 1 files changed, 23 insertions(+) diff -puN Documentation/filesystems/relayfs.txt~relayfs-add-documention-for-non-relay-files Documentation/filesystems/relayfs.txt --- devel/Documentation/filesystems/relayfs.txt~relayfs-add-documention-for-non-relay-files 2005-11-12 13:18:10.000000000 -0800 +++ devel-akpm/Documentation/filesystems/relayfs.txt 2005-11-12 13:18:10.000000000 -0800 @@ -125,6 +125,8 @@ Here's a summary of the API relayfs prov relay_reset(chan) relayfs_create_dir(name, parent) relayfs_remove_dir(dentry) + relayfs_create_file(name, parent, mode, fops, data) + relayfs_remove_file(dentry) channel management typically called on instigation of userspace: @@ -320,6 +322,27 @@ forces a sub-buffer switch on all the ch to finalize and process the last sub-buffers before the channel is closed. +Creating non-relay files +------------------------ + +relay_open() automatically creates files in the relayfs filesystem to +represent the per-cpu kernel buffers; it's often useful for +applications to be able to create their own files alongside the relay +files in the relayfs filesystem as well e.g. 'control' files much like +those created in /proc or debugfs for similar purposes, used to +communicate control information between the kernel and user sides of a +relayfs application. For this purpose the relayfs_create_file() and +relayfs_remove_file() API functions exist. For relayfs_create_file(), +the caller passes in a set of user-defined file operations to be used +for the file and an optional void * to a user-specified data item, +which will be accessible via inode->u.generic_ip (see the relay-apps +tarball for examples). The file_operations are a required parameter +to relayfs_create_file() and thus the semantics of these files are +completely defined by the caller. + +See the relay-apps tarball at http://relayfs.sourceforge.net for +examples of how these non-relay files are meant to be used. + Misc ---- _