xref: /openbmc/linux/arch/arm/xen/enlighten.c (revision 80ecbd24)
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/vcpu.h>
6 #include <xen/interface/xen.h>
7 #include <xen/interface/memory.h>
8 #include <xen/interface/hvm/params.h>
9 #include <xen/features.h>
10 #include <xen/platform_pci.h>
11 #include <xen/xenbus.h>
12 #include <xen/page.h>
13 #include <xen/interface/sched.h>
14 #include <xen/xen-ops.h>
15 #include <asm/xen/hypervisor.h>
16 #include <asm/xen/hypercall.h>
17 #include <asm/system_misc.h>
18 #include <linux/interrupt.h>
19 #include <linux/irqreturn.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_irq.h>
23 #include <linux/of_address.h>
24 
25 #include <linux/mm.h>
26 
27 struct start_info _xen_start_info;
28 struct start_info *xen_start_info = &_xen_start_info;
29 EXPORT_SYMBOL_GPL(xen_start_info);
30 
31 enum xen_domain_type xen_domain_type = XEN_NATIVE;
32 EXPORT_SYMBOL_GPL(xen_domain_type);
33 
34 struct shared_info xen_dummy_shared_info;
35 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
36 
37 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
38 static struct vcpu_info __percpu *xen_vcpu_info;
39 
40 /* These are unused until we support booting "pre-ballooned" */
41 unsigned long xen_released_pages;
42 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
43 
44 /* TODO: to be removed */
45 __read_mostly int xen_have_vector_callback;
46 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
47 
48 int xen_platform_pci_unplug = XEN_UNPLUG_ALL;
49 EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
50 
51 static __read_mostly int xen_events_irq = -1;
52 
53 /* map fgmfn of domid to lpfn in the current domain */
54 static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
55 			    unsigned int domid)
56 {
57 	int rc;
58 	struct xen_add_to_physmap_range xatp = {
59 		.domid = DOMID_SELF,
60 		.foreign_domid = domid,
61 		.size = 1,
62 		.space = XENMAPSPACE_gmfn_foreign,
63 	};
64 	xen_ulong_t idx = fgmfn;
65 	xen_pfn_t gpfn = lpfn;
66 	int err = 0;
67 
68 	set_xen_guest_handle(xatp.idxs, &idx);
69 	set_xen_guest_handle(xatp.gpfns, &gpfn);
70 	set_xen_guest_handle(xatp.errs, &err);
71 
72 	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
73 	if (rc || err) {
74 		pr_warn("Failed to map pfn to mfn rc:%d:%d pfn:%lx mfn:%lx\n",
75 			rc, err, lpfn, fgmfn);
76 		return 1;
77 	}
78 	return 0;
79 }
80 
81 struct remap_data {
82 	xen_pfn_t fgmfn; /* foreign domain's gmfn */
83 	pgprot_t prot;
84 	domid_t  domid;
85 	struct vm_area_struct *vma;
86 	int index;
87 	struct page **pages;
88 	struct xen_remap_mfn_info *info;
89 };
90 
91 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
92 			void *data)
93 {
94 	struct remap_data *info = data;
95 	struct page *page = info->pages[info->index++];
96 	unsigned long pfn = page_to_pfn(page);
97 	pte_t pte = pfn_pte(pfn, info->prot);
98 
99 	if (map_foreign_page(pfn, info->fgmfn, info->domid))
100 		return -EFAULT;
101 	set_pte_at(info->vma->vm_mm, addr, ptep, pte);
102 
103 	return 0;
104 }
105 
106 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
107 			       unsigned long addr,
108 			       xen_pfn_t mfn, int nr,
109 			       pgprot_t prot, unsigned domid,
110 			       struct page **pages)
111 {
112 	int err;
113 	struct remap_data data;
114 
115 	/* TBD: Batching, current sole caller only does page at a time */
116 	if (nr > 1)
117 		return -EINVAL;
118 
119 	data.fgmfn = mfn;
120 	data.prot = prot;
121 	data.domid = domid;
122 	data.vma = vma;
123 	data.index = 0;
124 	data.pages = pages;
125 	err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
126 				  remap_pte_fn, &data);
127 	return err;
128 }
129 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
130 
131 int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
132 			       int nr, struct page **pages)
133 {
134 	int i;
135 
136 	for (i = 0; i < nr; i++) {
137 		struct xen_remove_from_physmap xrp;
138 		unsigned long rc, pfn;
139 
140 		pfn = page_to_pfn(pages[i]);
141 
142 		xrp.domid = DOMID_SELF;
143 		xrp.gpfn = pfn;
144 		rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
145 		if (rc) {
146 			pr_warn("Failed to unmap pfn:%lx rc:%ld\n",
147 				pfn, rc);
148 			return rc;
149 		}
150 	}
151 	return 0;
152 }
153 EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
154 
155 static void __init xen_percpu_init(void *unused)
156 {
157 	struct vcpu_register_vcpu_info info;
158 	struct vcpu_info *vcpup;
159 	int err;
160 	int cpu = get_cpu();
161 
162 	pr_info("Xen: initializing cpu%d\n", cpu);
163 	vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
164 
165 	info.mfn = __pa(vcpup) >> PAGE_SHIFT;
166 	info.offset = offset_in_page(vcpup);
167 
168 	err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
169 	BUG_ON(err);
170 	per_cpu(xen_vcpu, cpu) = vcpup;
171 
172 	enable_percpu_irq(xen_events_irq, 0);
173 	put_cpu();
174 }
175 
176 static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
177 {
178 	struct sched_shutdown r = { .reason = SHUTDOWN_reboot };
179 	int rc;
180 	rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
181 	if (rc)
182 		BUG();
183 }
184 
185 static void xen_power_off(void)
186 {
187 	struct sched_shutdown r = { .reason = SHUTDOWN_poweroff };
188 	int rc;
189 	rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
190 	if (rc)
191 		BUG();
192 }
193 
194 /*
195  * see Documentation/devicetree/bindings/arm/xen.txt for the
196  * documentation of the Xen Device Tree format.
197  */
198 #define GRANT_TABLE_PHYSADDR 0
199 static int __init xen_guest_init(void)
200 {
201 	struct xen_add_to_physmap xatp;
202 	static struct shared_info *shared_info_page = 0;
203 	struct device_node *node;
204 	int len;
205 	const char *s = NULL;
206 	const char *version = NULL;
207 	const char *xen_prefix = "xen,xen-";
208 	struct resource res;
209 
210 	node = of_find_compatible_node(NULL, NULL, "xen,xen");
211 	if (!node) {
212 		pr_debug("No Xen support\n");
213 		return 0;
214 	}
215 	s = of_get_property(node, "compatible", &len);
216 	if (strlen(xen_prefix) + 3  < len &&
217 			!strncmp(xen_prefix, s, strlen(xen_prefix)))
218 		version = s + strlen(xen_prefix);
219 	if (version == NULL) {
220 		pr_debug("Xen version not found\n");
221 		return 0;
222 	}
223 	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
224 		return 0;
225 	xen_hvm_resume_frames = res.start >> PAGE_SHIFT;
226 	xen_events_irq = irq_of_parse_and_map(node, 0);
227 	pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n",
228 			version, xen_events_irq, xen_hvm_resume_frames);
229 	xen_domain_type = XEN_HVM_DOMAIN;
230 
231 	xen_setup_features();
232 	if (xen_feature(XENFEAT_dom0))
233 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
234 	else
235 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
236 
237 	if (!shared_info_page)
238 		shared_info_page = (struct shared_info *)
239 			get_zeroed_page(GFP_KERNEL);
240 	if (!shared_info_page) {
241 		pr_err("not enough memory\n");
242 		return -ENOMEM;
243 	}
244 	xatp.domid = DOMID_SELF;
245 	xatp.idx = 0;
246 	xatp.space = XENMAPSPACE_shared_info;
247 	xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
248 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
249 		BUG();
250 
251 	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
252 
253 	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
254 	 * page, we use it in the event channel upcall and in some pvclock
255 	 * related functions.
256 	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
257 	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
258 	 * for secondary CPUs as they are brought up.
259 	 * For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
260 	 */
261 	xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info),
262 			                       sizeof(struct vcpu_info));
263 	if (xen_vcpu_info == NULL)
264 		return -ENOMEM;
265 
266 	gnttab_init();
267 	if (!xen_initial_domain())
268 		xenbus_probe(NULL);
269 
270 	return 0;
271 }
272 core_initcall(xen_guest_init);
273 
274 static int __init xen_pm_init(void)
275 {
276 	pm_power_off = xen_power_off;
277 	arm_pm_restart = xen_restart;
278 
279 	return 0;
280 }
281 subsys_initcall(xen_pm_init);
282 
283 static irqreturn_t xen_arm_callback(int irq, void *arg)
284 {
285 	xen_hvm_evtchn_do_upcall();
286 	return IRQ_HANDLED;
287 }
288 
289 static int __init xen_init_events(void)
290 {
291 	if (!xen_domain() || xen_events_irq < 0)
292 		return -ENODEV;
293 
294 	xen_init_IRQ();
295 
296 	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
297 			"events", &xen_vcpu)) {
298 		pr_err("Error requesting IRQ %d\n", xen_events_irq);
299 		return -EINVAL;
300 	}
301 
302 	on_each_cpu(xen_percpu_init, NULL, 0);
303 
304 	return 0;
305 }
306 postcore_initcall(xen_init_events);
307 
308 /* In the hypervisor.S file. */
309 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
310 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
311 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
312 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
313 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
314 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
315 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
316 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
317 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
318 EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
319 EXPORT_SYMBOL_GPL(privcmd_call);
320