diff options
| -rw-r--r-- | net/sunrpc/rpc_pipe.c | 52 |
1 files changed, 51 insertions, 1 deletions
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c index c59f3ca2b41b..5364e2e52e07 100644 --- a/net/sunrpc/rpc_pipe.c +++ b/net/sunrpc/rpc_pipe.c @@ -76,6 +76,16 @@ rpc_timeout_upcall_queue(struct work_struct *work) rpc_purge_list(rpci, &free_list, destroy_msg, -ETIMEDOUT); } +/** + * rpc_queue_upcall + * @inode: inode of upcall pipe on which to queue given message + * @msg: message to queue + * + * Call with an @inode created by rpc_mkpipe() to queue an upcall. + * A userspace process may then later read the upcall by performing a + * read on an open file for this inode. It is up to the caller to + * initialize the fields of @msg (other than @msg->list) appropriately. + */ int rpc_queue_upcall(struct inode *inode, struct rpc_pipe_msg *msg) { @@ -663,7 +673,16 @@ rpc_lookup_negative(char *path, struct nameidata *nd) return dentry; } - +/** + * rpc_mkdir - Create a new directory in rpc_pipefs + * @path: path from the rpc_pipefs root to the new directory + * @rpc_clnt: rpc client to associate with this directory + * + * This creates a directory at the given @path associated with + * @rpc_clnt, which will contain a file named "info" with some basic + * information about the client, together with any "pipes" that may + * later be created using rpc_mkpipe(). + */ struct dentry * rpc_mkdir(char *path, struct rpc_clnt *rpc_client) { @@ -699,6 +718,10 @@ err_dput: goto out; } +/** + * rpc_rmdir - Remove a directory created with rpc_mkdir() + * @dentry: directory to remove + */ int rpc_rmdir(struct dentry *dentry) { @@ -717,6 +740,25 @@ rpc_rmdir(struct dentry *dentry) return error; } +/** + * rpc_mkpipe - make an rpc_pipefs file for kernel<->userspace communication + * @parent: dentry of directory to create new "pipe" in + * @name: name of pipe + * @private: private data to associate with the pipe, for the caller's use + * @ops: operations defining the behavior of the pipe: upcall, downcall, + * release_pipe, and destroy_msg. + * + * Data is made available for userspace to read by calls to + * rpc_queue_upcall(). The actual reads will result in calls to + * @ops->upcall, which will be called with the file pointer, + * message, and userspace buffer to copy to. + * + * Writes can come at any time, and do not necessarily have to be + * responses to upcalls. They will result in calls to @msg->downcall. + * + * The @private argument passed here will be available to all these methods + * from the file pointer, via RPC_I(file->f_dentry->d_inode)->private. + */ struct dentry * rpc_mkpipe(struct dentry *parent, const char *name, void *private, struct rpc_pipe_ops *ops, int flags) { @@ -764,6 +806,14 @@ err_dput: goto out; } +/** + * rpc_unlink - remove a pipe + * @dentry: dentry for the pipe, as returned from rpc_mkpipe + * + * After this call, lookups will no longer find the pipe, and any + * attempts to read or write using preexisting opens of the pipe will + * return -EPIPE. + */ int rpc_unlink(struct dentry *dentry) { |