1 #ifndef _XEN_MULTICALLS_H
2 #define _XEN_MULTICALLS_H
3 
4 #include "xen-ops.h"
5 
6 /* Multicalls */
7 struct multicall_space
8 {
9 	struct multicall_entry *mc;
10 	void *args;
11 };
12 
13 /* Allocate room for a multicall and its args */
14 struct multicall_space __xen_mc_entry(size_t args);
15 
16 DECLARE_PER_CPU(unsigned long, xen_mc_irq_flags);
17 
18 /* Call to start a batch of multiple __xen_mc_entry()s.  Must be
19    paired with xen_mc_issue() */
xen_mc_batch(void)20 static inline void xen_mc_batch(void)
21 {
22 	unsigned long flags;
23 	/* need to disable interrupts until this entry is complete */
24 	local_irq_save(flags);
25 	__this_cpu_write(xen_mc_irq_flags, flags);
26 }
27 
xen_mc_entry(size_t args)28 static inline struct multicall_space xen_mc_entry(size_t args)
29 {
30 	xen_mc_batch();
31 	return __xen_mc_entry(args);
32 }
33 
34 /* Flush all pending multicalls */
35 void xen_mc_flush(void);
36 
37 /* Issue a multicall if we're not in a lazy mode */
xen_mc_issue(unsigned mode)38 static inline void xen_mc_issue(unsigned mode)
39 {
40 	if ((paravirt_get_lazy_mode() & mode) == 0)
41 		xen_mc_flush();
42 
43 	/* restore flags saved in xen_mc_batch */
44 	local_irq_restore(percpu_read(xen_mc_irq_flags));
45 }
46 
47 /* Set up a callback to be called when the current batch is flushed */
48 void xen_mc_callback(void (*fn)(void *), void *data);
49 
50 /*
51  * Try to extend the arguments of the previous multicall command.  The
52  * previous command's op must match.  If it does, then it attempts to
53  * extend the argument space allocated to the multicall entry by
54  * arg_size bytes.
55  *
56  * The returned multicall_space will return with mc pointing to the
57  * command on success, or NULL on failure, and args pointing to the
58  * newly allocated space.
59  */
60 struct multicall_space xen_mc_extend_args(unsigned long op, size_t arg_size);
61 
62 #endif /* _XEN_MULTICALLS_H */
63