From 03907beb680ee39bee212bb3cb170cb295238cda Mon Sep 17 00:00:00 2001 From: "kaf24@scramble.cl.cam.ac.uk" Date: Wed, 9 Jun 2004 16:36:08 +0000 Subject: bitkeeper revision 1.946 (40c73c7805slPvnfEohXfQoiriAESg) Rename Linux directories and upgrade build system. --- linux-2.4.26-xen-sparse/include/asm-xen/ctrl_if.h | 121 ++++++++++++++++++++++ 1 file changed, 121 insertions(+) create mode 100644 linux-2.4.26-xen-sparse/include/asm-xen/ctrl_if.h (limited to 'linux-2.4.26-xen-sparse/include/asm-xen/ctrl_if.h') diff --git a/linux-2.4.26-xen-sparse/include/asm-xen/ctrl_if.h b/linux-2.4.26-xen-sparse/include/asm-xen/ctrl_if.h new file mode 100644 index 0000000000..5bc6cc22b1 --- /dev/null +++ b/linux-2.4.26-xen-sparse/include/asm-xen/ctrl_if.h @@ -0,0 +1,121 @@ +/****************************************************************************** + * ctrl_if.h + * + * Management functions for special interface to the domain controller. + * + * Copyright (c) 2004, K A Fraser + */ + +#ifndef __ASM_XEN__CTRL_IF_H__ +#define __ASM_XEN__CTRL_IF_H__ + +#include +#include + +typedef control_msg_t ctrl_msg_t; + +/* + * Callback function type. Called for asynchronous processing of received + * request messages, and responses to previously-transmitted request messages. + * The parameters are (@msg, @id). + * @msg: Original request/response message (not a copy). The message can be + * modified in-place by the handler (e.g., a response callback can + * turn a request message into a response message in place). The message + * is no longer accessible after the callback handler returns -- if the + * message is required to persist for longer then it must be copied. + * @id: (Response callbacks only) The 'id' that was specified when the + * original request message was queued for transmission. + */ +typedef void (*ctrl_msg_handler_t)(ctrl_msg_t *, unsigned long); + +/* + * Send @msg to the domain controller. Execute @hnd when a response is + * received, passing the response message and the specified @id. This + * operation will not block: it will return -EAGAIN if there is no space. + * Notes: + * 1. The @msg is copied if it is transmitted and so can be freed after this + * function returns. + * 2. If @hnd is NULL then no callback is executed. + */ +int ctrl_if_send_message_noblock( + ctrl_msg_t *msg, + ctrl_msg_handler_t hnd, + unsigned long id); + +/* + * Send @msg to the domain controller. Execute @hnd when a response is + * received, passing the response message and the specified @id. This + * operation will block until the message is sent, or a signal is received + * for the calling process (unless @wait_state is TASK_UNINTERRUPTIBLE). + * Notes: + * 1. The @msg is copied if it is transmitted and so can be freed after this + * function returns. + * 2. If @hnd is NULL then no callback is executed. + */ +int ctrl_if_send_message_block( + ctrl_msg_t *msg, + ctrl_msg_handler_t hnd, + unsigned long id, + long wait_state); + +/* + * Request a callback when there is /possibly/ space to immediately send a + * message to the domain controller. This function returns 0 if there is + * already space to trasnmit a message --- in this case the callback task /may/ + * still be executed. If this function returns 1 then the callback /will/ be + * executed when space becomes available. + */ +int ctrl_if_enqueue_space_callback(struct tq_struct *task); + +/* + * Send a response (@msg) to a message from the domain controller. This will + * never block. + * Notes: + * 1. The @msg is copied and so can be freed after this function returns. + * 2. The @msg may be the original request message, modified in-place. + */ +void ctrl_if_send_response(ctrl_msg_t *msg); + +/* + * Register a receiver for typed messages from the domain controller. The + * handler (@hnd) is called for every received message of specified @type. + * Returns TRUE (non-zero) if the handler was successfully registered. + * If CALLBACK_IN_BLOCKING CONTEXT is specified in @flags then callbacks will + * occur in a context in which it is safe to yield (i.e., process context). + */ +#define CALLBACK_IN_BLOCKING_CONTEXT 1 +int ctrl_if_register_receiver( + u8 type, + ctrl_msg_handler_t hnd, + unsigned int flags); + +/* + * Unregister a receiver for typed messages from the domain controller. The + * handler (@hnd) will not be executed after this function returns. + */ +void ctrl_if_unregister_receiver(u8 type, ctrl_msg_handler_t hnd); + +/* Suspend/resume notifications. */ +void ctrl_if_suspend(void); +void ctrl_if_resume(void); + +/* Start-of-day setup. */ +void ctrl_if_init(void); + +/* + * Returns TRUE if there are no outstanding message requests at the domain + * controller. This can be used to ensure that messages have really flushed + * through when it is not possible to use the response-callback interface. + * WARNING: If other subsystems are using the control interface then this + * function might never return TRUE! + */ +int ctrl_if_transmitter_empty(void); /* !! DANGEROUS FUNCTION !! */ + +/* + * Manually discard response messages from the domain controller. + * WARNING: This is usually done automatically -- this function should only + * be called when normal interrupt mechanisms are disabled! + */ +void ctrl_if_discard_responses(void); /* !! DANGEROUS FUNCTION !! */ + +#endif /* __ASM_XEN__CONTROL_IF_H__ */ -- cgit v1.2.3