aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/xen/enlighten.c
blob: 59bcb96ac3692446989501f363301daa81674d5b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
#include <xen/xen.h>
#include <xen/events.h>
#include <xen/grant_table.h>
#include <xen/hvm.h>
#include <xen/interface/xen.h>
#include <xen/interface/memory.h>
#include <xen/interface/hvm/params.h>
#include <xen/features.h>
#include <xen/platform_pci.h>
#include <xen/xenbus.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
#include <linux/interrupt.h>
#include <linux/irqreturn.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>

struct start_info _xen_start_info;
struct start_info *xen_start_info = &_xen_start_info;
EXPORT_SYMBOL_GPL(xen_start_info);

enum xen_domain_type xen_domain_type = XEN_NATIVE;
EXPORT_SYMBOL_GPL(xen_domain_type);

struct shared_info xen_dummy_shared_info;
struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;

DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);

/* TODO: to be removed */
__read_mostly int xen_have_vector_callback;
EXPORT_SYMBOL_GPL(xen_have_vector_callback);

int xen_platform_pci_unplug = XEN_UNPLUG_ALL;
EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);

static __read_mostly int xen_events_irq = -1;

int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
			       unsigned long addr,
			       unsigned long mfn, int nr,
			       pgprot_t prot, unsigned domid)
{
	return -ENOSYS;
}
EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);

/*
 * see Documentation/devicetree/bindings/arm/xen.txt for the
 * documentation of the Xen Device Tree format.
 */
#define GRANT_TABLE_PHYSADDR 0
static int __init xen_guest_init(void)
{
	struct xen_add_to_physmap xatp;
	static struct shared_info *shared_info_page = 0;
	struct device_node *node;
	int len;
	const char *s = NULL;
	const char *version = NULL;
	const char *xen_prefix = "xen,xen-";
	struct resource res;

	node = of_find_compatible_node(NULL, NULL, "xen,xen");
	if (!node) {
		pr_debug("No Xen support\n");
		return 0;
	}
	s = of_get_property(node, "compatible", &len);
	if (strlen(xen_prefix) + 3  < len &&
			!strncmp(xen_prefix, s, strlen(xen_prefix)))
		version = s + strlen(xen_prefix);
	if (version == NULL) {
		pr_debug("Xen version not found\n");
		return 0;
	}
	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
		return 0;
	xen_hvm_resume_frames = res.start >> PAGE_SHIFT;
	xen_events_irq = irq_of_parse_and_map(node, 0);
	pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n",
			version, xen_events_irq, xen_hvm_resume_frames);
	xen_domain_type = XEN_HVM_DOMAIN;

	xen_setup_features();
	if (xen_feature(XENFEAT_dom0))
		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
	else
		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);

	if (!shared_info_page)
		shared_info_page = (struct shared_info *)
			get_zeroed_page(GFP_KERNEL);
	if (!shared_info_page) {
		pr_err("not enough memory\n");
		return -ENOMEM;
	}
	xatp.domid = DOMID_SELF;
	xatp.idx = 0;
	xatp.space = XENMAPSPACE_shared_info;
	xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
		BUG();

	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;

	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
	 * page, we use it in the event channel upcall and in some pvclock
	 * related functions. We don't need the vcpu_info placement
	 * optimizations because we don't use any pv_mmu or pv_irq op on
	 * HVM.
	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
	 * for secondary CPUs as they are brought up. */
	per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];

	gnttab_init();
	if (!xen_initial_domain())
		xenbus_probe(NULL);

	return 0;
}
core_initcall(xen_guest_init);

static irqreturn_t xen_arm_callback(int irq, void *arg)
{
	xen_hvm_evtchn_do_upcall();
	return IRQ_HANDLED;
}

static int __init xen_init_events(void)
{
	if (!xen_domain() || xen_events_irq < 0)
		return -ENODEV;

	xen_init_IRQ();

	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
			"events", xen_vcpu)) {
		pr_err("Error requesting IRQ %d\n", xen_events_irq);
		return -EINVAL;
	}

	enable_percpu_irq(xen_events_irq, 0);

	return 0;
}
postcore_initcall(xen_init_events);

/* XXX: only until balloon is properly working */
int alloc_xenballooned_pages(int nr_pages, struct page **pages, bool highmem)
{
	*pages = alloc_pages(highmem ? GFP_HIGHUSER : GFP_KERNEL,
			get_order(nr_pages));
	if (*pages == NULL)
		return -ENOMEM;
	return 0;
}
EXPORT_SYMBOL_GPL(alloc_xenballooned_pages);

void free_xenballooned_pages(int nr_pages, struct page **pages)
{
	kfree(*pages);
	*pages = NULL;
}
EXPORT_SYMBOL_GPL(free_xenballooned_pages);