1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _XEN_MULTICALLS_H
3#define _XEN_MULTICALLS_H
4
5#include <trace/events/xen.h>
6
7#include "xen-ops.h"
8
9/* Multicalls */
10struct multicall_space
11{
12 struct multicall_entry *mc;
13 void *args;
14};
15
16/* Allocate room for a multicall and its args */
17struct multicall_space __xen_mc_entry(size_t args);
18
19DECLARE_PER_CPU(unsigned long, xen_mc_irq_flags);
20
21/* Call to start a batch of multiple __xen_mc_entry()s. Must be
22 paired with xen_mc_issue() */
23static inline void xen_mc_batch(void)
24{
25 unsigned long flags;
26
27 /* need to disable interrupts until this entry is complete */
28 local_irq_save(flags);
29 trace_xen_mc_batch(mode: xen_get_lazy_mode());
30 __this_cpu_write(xen_mc_irq_flags, flags);
31}
32
33static inline struct multicall_space xen_mc_entry(size_t args)
34{
35 xen_mc_batch();
36 return __xen_mc_entry(args);
37}
38
39/* Flush all pending multicalls */
40void xen_mc_flush(void);
41
42/* Issue a multicall if we're not in a lazy mode */
43static inline void xen_mc_issue(unsigned mode)
44{
45 trace_xen_mc_issue(mode);
46
47 if ((xen_get_lazy_mode() & mode) == 0)
48 xen_mc_flush();
49
50 /* restore flags saved in xen_mc_batch */
51 local_irq_restore(this_cpu_read(xen_mc_irq_flags));
52}
53
54/* Set up a callback to be called when the current batch is flushed */
55void xen_mc_callback(void (*fn)(void *), void *data);
56
57/*
58 * Try to extend the arguments of the previous multicall command. The
59 * previous command's op must match. If it does, then it attempts to
60 * extend the argument space allocated to the multicall entry by
61 * arg_size bytes.
62 *
63 * The returned multicall_space will return with mc pointing to the
64 * command on success, or NULL on failure, and args pointing to the
65 * newly allocated space.
66 */
67struct multicall_space xen_mc_extend_args(unsigned long op, size_t arg_size);
68
69#endif /* _XEN_MULTICALLS_H */
70

source code of linux/arch/x86/xen/multicalls.h