xref: /linux/arch/x86/include/asm/xen/hypervisor.h (revision 78c3925c048c752334873f56c3a3d1c9d53e0416)
1 /******************************************************************************
2  * hypervisor.h
3  *
4  * Linux-specific hypervisor handling.
5  *
6  * Copyright (c) 2002-2004, K A Fraser
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License version 2
10  * as published by the Free Software Foundation; or, when distributed
11  * separately from the Linux kernel or incorporated into other
12  * software packages, subject to the following license:
13  *
14  * Permission is hereby granted, free of charge, to any person obtaining a copy
15  * of this source file (the "Software"), to deal in the Software without
16  * restriction, including without limitation the rights to use, copy, modify,
17  * merge, publish, distribute, sublicense, and/or sell copies of the Software,
18  * and to permit persons to whom the Software is furnished to do so, subject to
19  * the following conditions:
20  *
21  * The above copyright notice and this permission notice shall be included in
22  * all copies or substantial portions of the Software.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
25  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
26  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
27  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
28  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
29  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
30  * IN THE SOFTWARE.
31  */
32 
33 #ifndef _ASM_X86_XEN_HYPERVISOR_H
34 #define _ASM_X86_XEN_HYPERVISOR_H
35 
36 extern struct shared_info *HYPERVISOR_shared_info;
37 extern struct start_info *xen_start_info;
38 
39 #include <asm/bug.h>
40 #include <asm/processor.h>
41 
42 #define XEN_SIGNATURE "XenVMMXenVMM"
43 
44 static inline uint32_t xen_cpuid_base(void)
45 {
46 	return hypervisor_cpuid_base(XEN_SIGNATURE, 2);
47 }
48 
49 struct pci_dev;
50 
51 #ifdef CONFIG_XEN_PV_DOM0
52 bool xen_initdom_restore_msi(struct pci_dev *dev);
53 #else
54 static inline bool xen_initdom_restore_msi(struct pci_dev *dev) { return true; }
55 #endif
56 
57 #ifdef CONFIG_HOTPLUG_CPU
58 void xen_arch_register_cpu(int num);
59 void xen_arch_unregister_cpu(int num);
60 #endif
61 
62 #ifdef CONFIG_PVH
63 void __init xen_pvh_init(struct boot_params *boot_params);
64 void __init mem_map_via_hcall(struct boot_params *boot_params_p);
65 #ifdef CONFIG_XEN_PVH
66 void __init xen_reserve_extra_memory(struct boot_params *bootp);
67 #else
68 static inline void xen_reserve_extra_memory(struct boot_params *bootp) { }
69 #endif
70 #endif
71 
72 /* Lazy mode for batching updates / context switch */
73 enum xen_lazy_mode {
74 	XEN_LAZY_NONE,
75 	XEN_LAZY_MMU,
76 	XEN_LAZY_CPU,
77 };
78 
79 DECLARE_PER_CPU(enum xen_lazy_mode, xen_lazy_mode);
80 DECLARE_PER_CPU(unsigned int, xen_lazy_nesting);
81 
82 static inline void enter_lazy(enum xen_lazy_mode mode)
83 {
84 	enum xen_lazy_mode old_mode = this_cpu_read(xen_lazy_mode);
85 
86 	if (mode == old_mode) {
87 		this_cpu_inc(xen_lazy_nesting);
88 		return;
89 	}
90 
91 	BUG_ON(old_mode != XEN_LAZY_NONE);
92 
93 	this_cpu_write(xen_lazy_mode, mode);
94 }
95 
96 static inline void leave_lazy(enum xen_lazy_mode mode)
97 {
98 	BUG_ON(this_cpu_read(xen_lazy_mode) != mode);
99 
100 	if (this_cpu_read(xen_lazy_nesting) == 0)
101 		this_cpu_write(xen_lazy_mode, XEN_LAZY_NONE);
102 	else
103 		this_cpu_dec(xen_lazy_nesting);
104 }
105 
106 enum xen_lazy_mode xen_get_lazy_mode(void);
107 
108 #if defined(CONFIG_XEN_DOM0) && defined(CONFIG_ACPI)
109 void xen_sanitize_proc_cap_bits(uint32_t *buf);
110 #else
111 static inline void xen_sanitize_proc_cap_bits(uint32_t *buf)
112 {
113 	BUG();
114 }
115 #endif
116 
117 #endif /* _ASM_X86_XEN_HYPERVISOR_H */
118