xref: /openbmc/linux/arch/arm/xen/enlighten.c (revision 275876e2)
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 #include <linux/cpuidle.h>
25 #include <linux/cpufreq.h>
26 #include <linux/cpu.h>
27 
28 #include <linux/mm.h>
29 
30 struct start_info _xen_start_info;
31 struct start_info *xen_start_info = &_xen_start_info;
32 EXPORT_SYMBOL_GPL(xen_start_info);
33 
34 enum xen_domain_type xen_domain_type = XEN_NATIVE;
35 EXPORT_SYMBOL_GPL(xen_domain_type);
36 
37 struct shared_info xen_dummy_shared_info;
38 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
39 
40 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
41 static struct vcpu_info __percpu *xen_vcpu_info;
42 
43 /* These are unused until we support booting "pre-ballooned" */
44 unsigned long xen_released_pages;
45 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
46 
47 /* TODO: to be removed */
48 __read_mostly int xen_have_vector_callback;
49 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
50 
51 int xen_platform_pci_unplug = XEN_UNPLUG_ALL;
52 EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
53 
54 static __read_mostly int xen_events_irq = -1;
55 
56 /* map fgmfn of domid to lpfn in the current domain */
57 static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
58 			    unsigned int domid)
59 {
60 	int rc;
61 	struct xen_add_to_physmap_range xatp = {
62 		.domid = DOMID_SELF,
63 		.foreign_domid = domid,
64 		.size = 1,
65 		.space = XENMAPSPACE_gmfn_foreign,
66 	};
67 	xen_ulong_t idx = fgmfn;
68 	xen_pfn_t gpfn = lpfn;
69 	int err = 0;
70 
71 	set_xen_guest_handle(xatp.idxs, &idx);
72 	set_xen_guest_handle(xatp.gpfns, &gpfn);
73 	set_xen_guest_handle(xatp.errs, &err);
74 
75 	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
76 	if (rc || err) {
77 		pr_warn("Failed to map pfn to mfn rc:%d:%d pfn:%lx mfn:%lx\n",
78 			rc, err, lpfn, fgmfn);
79 		return 1;
80 	}
81 	return 0;
82 }
83 
84 struct remap_data {
85 	xen_pfn_t fgmfn; /* foreign domain's gmfn */
86 	pgprot_t prot;
87 	domid_t  domid;
88 	struct vm_area_struct *vma;
89 	int index;
90 	struct page **pages;
91 	struct xen_remap_mfn_info *info;
92 };
93 
94 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
95 			void *data)
96 {
97 	struct remap_data *info = data;
98 	struct page *page = info->pages[info->index++];
99 	unsigned long pfn = page_to_pfn(page);
100 	pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot));
101 
102 	if (map_foreign_page(pfn, info->fgmfn, info->domid))
103 		return -EFAULT;
104 	set_pte_at(info->vma->vm_mm, addr, ptep, pte);
105 
106 	return 0;
107 }
108 
109 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
110 			       unsigned long addr,
111 			       xen_pfn_t mfn, int nr,
112 			       pgprot_t prot, unsigned domid,
113 			       struct page **pages)
114 {
115 	int err;
116 	struct remap_data data;
117 
118 	/* TBD: Batching, current sole caller only does page at a time */
119 	if (nr > 1)
120 		return -EINVAL;
121 
122 	data.fgmfn = mfn;
123 	data.prot = prot;
124 	data.domid = domid;
125 	data.vma = vma;
126 	data.index = 0;
127 	data.pages = pages;
128 	err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
129 				  remap_pte_fn, &data);
130 	return err;
131 }
132 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
133 
134 int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
135 			       int nr, struct page **pages)
136 {
137 	int i;
138 
139 	for (i = 0; i < nr; i++) {
140 		struct xen_remove_from_physmap xrp;
141 		unsigned long rc, pfn;
142 
143 		pfn = page_to_pfn(pages[i]);
144 
145 		xrp.domid = DOMID_SELF;
146 		xrp.gpfn = pfn;
147 		rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
148 		if (rc) {
149 			pr_warn("Failed to unmap pfn:%lx rc:%ld\n",
150 				pfn, rc);
151 			return rc;
152 		}
153 	}
154 	return 0;
155 }
156 EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
157 
158 static void xen_percpu_init(void)
159 {
160 	struct vcpu_register_vcpu_info info;
161 	struct vcpu_info *vcpup;
162 	int err;
163 	int cpu = get_cpu();
164 
165 	pr_info("Xen: initializing cpu%d\n", cpu);
166 	vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
167 
168 	info.mfn = __pa(vcpup) >> PAGE_SHIFT;
169 	info.offset = offset_in_page(vcpup);
170 
171 	err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
172 	BUG_ON(err);
173 	per_cpu(xen_vcpu, cpu) = vcpup;
174 
175 	enable_percpu_irq(xen_events_irq, 0);
176 	put_cpu();
177 }
178 
179 static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
180 {
181 	struct sched_shutdown r = { .reason = SHUTDOWN_reboot };
182 	int rc;
183 	rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
184 	BUG_ON(rc);
185 }
186 
187 static void xen_power_off(void)
188 {
189 	struct sched_shutdown r = { .reason = SHUTDOWN_poweroff };
190 	int rc;
191 	rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
192 	BUG_ON(rc);
193 }
194 
195 static int xen_cpu_notification(struct notifier_block *self,
196 				unsigned long action,
197 				void *hcpu)
198 {
199 	switch (action) {
200 	case CPU_STARTING:
201 		xen_percpu_init();
202 		break;
203 	default:
204 		break;
205 	}
206 
207 	return NOTIFY_OK;
208 }
209 
210 static struct notifier_block xen_cpu_notifier = {
211 	.notifier_call = xen_cpu_notification,
212 };
213 
214 static irqreturn_t xen_arm_callback(int irq, void *arg)
215 {
216 	xen_hvm_evtchn_do_upcall();
217 	return IRQ_HANDLED;
218 }
219 
220 /*
221  * see Documentation/devicetree/bindings/arm/xen.txt for the
222  * documentation of the Xen Device Tree format.
223  */
224 #define GRANT_TABLE_PHYSADDR 0
225 static int __init xen_guest_init(void)
226 {
227 	struct xen_add_to_physmap xatp;
228 	static struct shared_info *shared_info_page = 0;
229 	struct device_node *node;
230 	int len;
231 	const char *s = NULL;
232 	const char *version = NULL;
233 	const char *xen_prefix = "xen,xen-";
234 	struct resource res;
235 	phys_addr_t grant_frames;
236 
237 	node = of_find_compatible_node(NULL, NULL, "xen,xen");
238 	if (!node) {
239 		pr_debug("No Xen support\n");
240 		return 0;
241 	}
242 	s = of_get_property(node, "compatible", &len);
243 	if (strlen(xen_prefix) + 3  < len &&
244 			!strncmp(xen_prefix, s, strlen(xen_prefix)))
245 		version = s + strlen(xen_prefix);
246 	if (version == NULL) {
247 		pr_debug("Xen version not found\n");
248 		return 0;
249 	}
250 	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
251 		return 0;
252 	grant_frames = res.start;
253 	xen_events_irq = irq_of_parse_and_map(node, 0);
254 	pr_info("Xen %s support found, events_irq=%d gnttab_frame=%pa\n",
255 			version, xen_events_irq, &grant_frames);
256 
257 	if (xen_events_irq < 0)
258 		return -ENODEV;
259 
260 	xen_domain_type = XEN_HVM_DOMAIN;
261 
262 	xen_setup_features();
263 	if (xen_feature(XENFEAT_dom0))
264 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
265 	else
266 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
267 
268 	if (!shared_info_page)
269 		shared_info_page = (struct shared_info *)
270 			get_zeroed_page(GFP_KERNEL);
271 	if (!shared_info_page) {
272 		pr_err("not enough memory\n");
273 		return -ENOMEM;
274 	}
275 	xatp.domid = DOMID_SELF;
276 	xatp.idx = 0;
277 	xatp.space = XENMAPSPACE_shared_info;
278 	xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
279 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
280 		BUG();
281 
282 	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
283 
284 	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
285 	 * page, we use it in the event channel upcall and in some pvclock
286 	 * related functions.
287 	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
288 	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
289 	 * for secondary CPUs as they are brought up.
290 	 * For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
291 	 */
292 	xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info),
293 			                       sizeof(struct vcpu_info));
294 	if (xen_vcpu_info == NULL)
295 		return -ENOMEM;
296 
297 	if (gnttab_setup_auto_xlat_frames(grant_frames)) {
298 		free_percpu(xen_vcpu_info);
299 		return -ENOMEM;
300 	}
301 	gnttab_init();
302 	if (!xen_initial_domain())
303 		xenbus_probe(NULL);
304 
305 	/*
306 	 * Making sure board specific code will not set up ops for
307 	 * cpu idle and cpu freq.
308 	 */
309 	disable_cpuidle();
310 	disable_cpufreq();
311 
312 	xen_init_IRQ();
313 
314 	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
315 			       "events", &xen_vcpu)) {
316 		pr_err("Error request IRQ %d\n", xen_events_irq);
317 		return -EINVAL;
318 	}
319 
320 	xen_percpu_init();
321 
322 	register_cpu_notifier(&xen_cpu_notifier);
323 
324 	return 0;
325 }
326 early_initcall(xen_guest_init);
327 
328 static int __init xen_pm_init(void)
329 {
330 	if (!xen_domain())
331 		return -ENODEV;
332 
333 	pm_power_off = xen_power_off;
334 	arm_pm_restart = xen_restart;
335 
336 	return 0;
337 }
338 late_initcall(xen_pm_init);
339 
340 
341 /* empty stubs */
342 void xen_arch_pre_suspend(void) { }
343 void xen_arch_post_suspend(int suspend_cancelled) { }
344 void xen_timer_resume(void) { }
345 void xen_arch_resume(void) { }
346 
347 
348 /* In the hypervisor.S file. */
349 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
350 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
351 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
352 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
353 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
354 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
355 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
356 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
357 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
358 EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
359 EXPORT_SYMBOL_GPL(HYPERVISOR_multicall);
360 EXPORT_SYMBOL_GPL(privcmd_call);
361