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 */ |
10 | struct multicall_space |
11 | { |
12 | struct multicall_entry *mc; |
13 | void *args; |
14 | }; |
15 | |
16 | /* Allocate room for a multicall and its args */ |
17 | struct multicall_space __xen_mc_entry(size_t args); |
18 | |
19 | DECLARE_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() */ |
23 | static 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 | |
33 | static 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 */ |
40 | void xen_mc_flush(void); |
41 | |
42 | /* Issue a multicall if we're not in a lazy mode */ |
43 | static 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 */ |
55 | void 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 | */ |
67 | struct multicall_space xen_mc_extend_args(unsigned long op, size_t arg_size); |
68 | |
69 | #endif /* _XEN_MULTICALLS_H */ |
70 | |