xref: /linux/arch/arm/xen/enlighten.c (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
1 #include <xen/xen.h>
2 #include <xen/events.h>
3 #include <xen/grant_table.h>
4 #include <xen/hvm.h>
5 #include <xen/interface/xen.h>
6 #include <xen/interface/memory.h>
7 #include <xen/interface/hvm/params.h>
8 #include <xen/features.h>
9 #include <xen/platform_pci.h>
10 #include <xen/xenbus.h>
11 #include <xen/page.h>
12 #include <xen/xen-ops.h>
13 #include <asm/xen/hypervisor.h>
14 #include <asm/xen/hypercall.h>
15 #include <linux/interrupt.h>
16 #include <linux/irqreturn.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/of_irq.h>
20 #include <linux/of_address.h>
21 
22 #include <linux/mm.h>
23 
24 struct start_info _xen_start_info;
25 struct start_info *xen_start_info = &_xen_start_info;
26 EXPORT_SYMBOL_GPL(xen_start_info);
27 
28 enum xen_domain_type xen_domain_type = XEN_NATIVE;
29 EXPORT_SYMBOL_GPL(xen_domain_type);
30 
31 struct shared_info xen_dummy_shared_info;
32 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
33 
34 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
35 
36 /* These are unused until we support booting "pre-ballooned" */
37 unsigned long xen_released_pages;
38 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
39 
40 /* TODO: to be removed */
41 __read_mostly int xen_have_vector_callback;
42 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
43 
44 int xen_platform_pci_unplug = XEN_UNPLUG_ALL;
45 EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
46 
47 static __read_mostly int xen_events_irq = -1;
48 
49 /* map fgmfn of domid to lpfn in the current domain */
50 static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
51 			    unsigned int domid)
52 {
53 	int rc;
54 	struct xen_add_to_physmap_range xatp = {
55 		.domid = DOMID_SELF,
56 		.foreign_domid = domid,
57 		.size = 1,
58 		.space = XENMAPSPACE_gmfn_foreign,
59 	};
60 	xen_ulong_t idx = fgmfn;
61 	xen_pfn_t gpfn = lpfn;
62 
63 	set_xen_guest_handle(xatp.idxs, &idx);
64 	set_xen_guest_handle(xatp.gpfns, &gpfn);
65 
66 	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
67 	if (rc) {
68 		pr_warn("Failed to map pfn to mfn rc:%d pfn:%lx mfn:%lx\n",
69 			rc, lpfn, fgmfn);
70 		return 1;
71 	}
72 	return 0;
73 }
74 
75 struct remap_data {
76 	xen_pfn_t fgmfn; /* foreign domain's gmfn */
77 	pgprot_t prot;
78 	domid_t  domid;
79 	struct vm_area_struct *vma;
80 	int index;
81 	struct page **pages;
82 	struct xen_remap_mfn_info *info;
83 };
84 
85 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
86 			void *data)
87 {
88 	struct remap_data *info = data;
89 	struct page *page = info->pages[info->index++];
90 	unsigned long pfn = page_to_pfn(page);
91 	pte_t pte = pfn_pte(pfn, info->prot);
92 
93 	if (map_foreign_page(pfn, info->fgmfn, info->domid))
94 		return -EFAULT;
95 	set_pte_at(info->vma->vm_mm, addr, ptep, pte);
96 
97 	return 0;
98 }
99 
100 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
101 			       unsigned long addr,
102 			       xen_pfn_t mfn, int nr,
103 			       pgprot_t prot, unsigned domid,
104 			       struct page **pages)
105 {
106 	int err;
107 	struct remap_data data;
108 
109 	/* TBD: Batching, current sole caller only does page at a time */
110 	if (nr > 1)
111 		return -EINVAL;
112 
113 	data.fgmfn = mfn;
114 	data.prot = prot;
115 	data.domid = domid;
116 	data.vma = vma;
117 	data.index = 0;
118 	data.pages = pages;
119 	err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
120 				  remap_pte_fn, &data);
121 	return err;
122 }
123 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
124 
125 int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
126 			       int nr, struct page **pages)
127 {
128 	int i;
129 
130 	for (i = 0; i < nr; i++) {
131 		struct xen_remove_from_physmap xrp;
132 		unsigned long rc, pfn;
133 
134 		pfn = page_to_pfn(pages[i]);
135 
136 		xrp.domid = DOMID_SELF;
137 		xrp.gpfn = pfn;
138 		rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
139 		if (rc) {
140 			pr_warn("Failed to unmap pfn:%lx rc:%ld\n",
141 				pfn, rc);
142 			return rc;
143 		}
144 	}
145 	return 0;
146 }
147 EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
148 
149 /*
150  * see Documentation/devicetree/bindings/arm/xen.txt for the
151  * documentation of the Xen Device Tree format.
152  */
153 #define GRANT_TABLE_PHYSADDR 0
154 static int __init xen_guest_init(void)
155 {
156 	struct xen_add_to_physmap xatp;
157 	static struct shared_info *shared_info_page = 0;
158 	struct device_node *node;
159 	int len;
160 	const char *s = NULL;
161 	const char *version = NULL;
162 	const char *xen_prefix = "xen,xen-";
163 	struct resource res;
164 
165 	node = of_find_compatible_node(NULL, NULL, "xen,xen");
166 	if (!node) {
167 		pr_debug("No Xen support\n");
168 		return 0;
169 	}
170 	s = of_get_property(node, "compatible", &len);
171 	if (strlen(xen_prefix) + 3  < len &&
172 			!strncmp(xen_prefix, s, strlen(xen_prefix)))
173 		version = s + strlen(xen_prefix);
174 	if (version == NULL) {
175 		pr_debug("Xen version not found\n");
176 		return 0;
177 	}
178 	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
179 		return 0;
180 	xen_hvm_resume_frames = res.start >> PAGE_SHIFT;
181 	xen_events_irq = irq_of_parse_and_map(node, 0);
182 	pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n",
183 			version, xen_events_irq, xen_hvm_resume_frames);
184 	xen_domain_type = XEN_HVM_DOMAIN;
185 
186 	xen_setup_features();
187 	if (xen_feature(XENFEAT_dom0))
188 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
189 	else
190 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
191 
192 	if (!shared_info_page)
193 		shared_info_page = (struct shared_info *)
194 			get_zeroed_page(GFP_KERNEL);
195 	if (!shared_info_page) {
196 		pr_err("not enough memory\n");
197 		return -ENOMEM;
198 	}
199 	xatp.domid = DOMID_SELF;
200 	xatp.idx = 0;
201 	xatp.space = XENMAPSPACE_shared_info;
202 	xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
203 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
204 		BUG();
205 
206 	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
207 
208 	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
209 	 * page, we use it in the event channel upcall and in some pvclock
210 	 * related functions. We don't need the vcpu_info placement
211 	 * optimizations because we don't use any pv_mmu or pv_irq op on
212 	 * HVM.
213 	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
214 	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
215 	 * for secondary CPUs as they are brought up. */
216 	per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
217 
218 	gnttab_init();
219 	if (!xen_initial_domain())
220 		xenbus_probe(NULL);
221 
222 	return 0;
223 }
224 core_initcall(xen_guest_init);
225 
226 static irqreturn_t xen_arm_callback(int irq, void *arg)
227 {
228 	xen_hvm_evtchn_do_upcall();
229 	return IRQ_HANDLED;
230 }
231 
232 static int __init xen_init_events(void)
233 {
234 	if (!xen_domain() || xen_events_irq < 0)
235 		return -ENODEV;
236 
237 	xen_init_IRQ();
238 
239 	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
240 			"events", xen_vcpu)) {
241 		pr_err("Error requesting IRQ %d\n", xen_events_irq);
242 		return -EINVAL;
243 	}
244 
245 	enable_percpu_irq(xen_events_irq, 0);
246 
247 	return 0;
248 }
249 postcore_initcall(xen_init_events);
250 
251 /* In the hypervisor.S file. */
252 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
253 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
254 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
255 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
256 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
257 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
258 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
259 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
260 EXPORT_SYMBOL_GPL(privcmd_call);
261