xref: /openbmc/linux/arch/arm/xen/enlighten.c (revision 930beb5a)
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 
27 #include <linux/mm.h>
28 
29 struct start_info _xen_start_info;
30 struct start_info *xen_start_info = &_xen_start_info;
31 EXPORT_SYMBOL_GPL(xen_start_info);
32 
33 enum xen_domain_type xen_domain_type = XEN_NATIVE;
34 EXPORT_SYMBOL_GPL(xen_domain_type);
35 
36 struct shared_info xen_dummy_shared_info;
37 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
38 
39 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
40 static struct vcpu_info __percpu *xen_vcpu_info;
41 
42 /* These are unused until we support booting "pre-ballooned" */
43 unsigned long xen_released_pages;
44 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
45 
46 /* TODO: to be removed */
47 __read_mostly int xen_have_vector_callback;
48 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
49 
50 int xen_platform_pci_unplug = XEN_UNPLUG_ALL;
51 EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
52 
53 static __read_mostly int xen_events_irq = -1;
54 
55 /* map fgmfn of domid to lpfn in the current domain */
56 static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
57 			    unsigned int domid)
58 {
59 	int rc;
60 	struct xen_add_to_physmap_range xatp = {
61 		.domid = DOMID_SELF,
62 		.foreign_domid = domid,
63 		.size = 1,
64 		.space = XENMAPSPACE_gmfn_foreign,
65 	};
66 	xen_ulong_t idx = fgmfn;
67 	xen_pfn_t gpfn = lpfn;
68 	int err = 0;
69 
70 	set_xen_guest_handle(xatp.idxs, &idx);
71 	set_xen_guest_handle(xatp.gpfns, &gpfn);
72 	set_xen_guest_handle(xatp.errs, &err);
73 
74 	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
75 	if (rc || err) {
76 		pr_warn("Failed to map pfn to mfn rc:%d:%d pfn:%lx mfn:%lx\n",
77 			rc, err, lpfn, fgmfn);
78 		return 1;
79 	}
80 	return 0;
81 }
82 
83 struct remap_data {
84 	xen_pfn_t fgmfn; /* foreign domain's gmfn */
85 	pgprot_t prot;
86 	domid_t  domid;
87 	struct vm_area_struct *vma;
88 	int index;
89 	struct page **pages;
90 	struct xen_remap_mfn_info *info;
91 };
92 
93 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
94 			void *data)
95 {
96 	struct remap_data *info = data;
97 	struct page *page = info->pages[info->index++];
98 	unsigned long pfn = page_to_pfn(page);
99 	pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot));
100 
101 	if (map_foreign_page(pfn, info->fgmfn, info->domid))
102 		return -EFAULT;
103 	set_pte_at(info->vma->vm_mm, addr, ptep, pte);
104 
105 	return 0;
106 }
107 
108 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
109 			       unsigned long addr,
110 			       xen_pfn_t mfn, int nr,
111 			       pgprot_t prot, unsigned domid,
112 			       struct page **pages)
113 {
114 	int err;
115 	struct remap_data data;
116 
117 	/* TBD: Batching, current sole caller only does page at a time */
118 	if (nr > 1)
119 		return -EINVAL;
120 
121 	data.fgmfn = mfn;
122 	data.prot = prot;
123 	data.domid = domid;
124 	data.vma = vma;
125 	data.index = 0;
126 	data.pages = pages;
127 	err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
128 				  remap_pte_fn, &data);
129 	return err;
130 }
131 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
132 
133 int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
134 			       int nr, struct page **pages)
135 {
136 	int i;
137 
138 	for (i = 0; i < nr; i++) {
139 		struct xen_remove_from_physmap xrp;
140 		unsigned long rc, pfn;
141 
142 		pfn = page_to_pfn(pages[i]);
143 
144 		xrp.domid = DOMID_SELF;
145 		xrp.gpfn = pfn;
146 		rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
147 		if (rc) {
148 			pr_warn("Failed to unmap pfn:%lx rc:%ld\n",
149 				pfn, rc);
150 			return rc;
151 		}
152 	}
153 	return 0;
154 }
155 EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
156 
157 static void __init xen_percpu_init(void *unused)
158 {
159 	struct vcpu_register_vcpu_info info;
160 	struct vcpu_info *vcpup;
161 	int err;
162 	int cpu = get_cpu();
163 
164 	pr_info("Xen: initializing cpu%d\n", cpu);
165 	vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
166 
167 	info.mfn = __pa(vcpup) >> PAGE_SHIFT;
168 	info.offset = offset_in_page(vcpup);
169 
170 	err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
171 	BUG_ON(err);
172 	per_cpu(xen_vcpu, cpu) = vcpup;
173 
174 	enable_percpu_irq(xen_events_irq, 0);
175 	put_cpu();
176 }
177 
178 static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
179 {
180 	struct sched_shutdown r = { .reason = SHUTDOWN_reboot };
181 	int rc;
182 	rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
183 	if (rc)
184 		BUG();
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 	if (rc)
193 		BUG();
194 }
195 
196 /*
197  * see Documentation/devicetree/bindings/arm/xen.txt for the
198  * documentation of the Xen Device Tree format.
199  */
200 #define GRANT_TABLE_PHYSADDR 0
201 static int __init xen_guest_init(void)
202 {
203 	struct xen_add_to_physmap xatp;
204 	static struct shared_info *shared_info_page = 0;
205 	struct device_node *node;
206 	int len;
207 	const char *s = NULL;
208 	const char *version = NULL;
209 	const char *xen_prefix = "xen,xen-";
210 	struct resource res;
211 
212 	node = of_find_compatible_node(NULL, NULL, "xen,xen");
213 	if (!node) {
214 		pr_debug("No Xen support\n");
215 		return 0;
216 	}
217 	s = of_get_property(node, "compatible", &len);
218 	if (strlen(xen_prefix) + 3  < len &&
219 			!strncmp(xen_prefix, s, strlen(xen_prefix)))
220 		version = s + strlen(xen_prefix);
221 	if (version == NULL) {
222 		pr_debug("Xen version not found\n");
223 		return 0;
224 	}
225 	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
226 		return 0;
227 	xen_hvm_resume_frames = res.start;
228 	xen_events_irq = irq_of_parse_and_map(node, 0);
229 	pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n",
230 			version, xen_events_irq, (xen_hvm_resume_frames >> PAGE_SHIFT));
231 	xen_domain_type = XEN_HVM_DOMAIN;
232 
233 	xen_setup_features();
234 	if (xen_feature(XENFEAT_dom0))
235 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
236 	else
237 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
238 
239 	if (!shared_info_page)
240 		shared_info_page = (struct shared_info *)
241 			get_zeroed_page(GFP_KERNEL);
242 	if (!shared_info_page) {
243 		pr_err("not enough memory\n");
244 		return -ENOMEM;
245 	}
246 	xatp.domid = DOMID_SELF;
247 	xatp.idx = 0;
248 	xatp.space = XENMAPSPACE_shared_info;
249 	xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
250 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
251 		BUG();
252 
253 	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
254 
255 	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
256 	 * page, we use it in the event channel upcall and in some pvclock
257 	 * related functions.
258 	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
259 	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
260 	 * for secondary CPUs as they are brought up.
261 	 * For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
262 	 */
263 	xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info),
264 			                       sizeof(struct vcpu_info));
265 	if (xen_vcpu_info == NULL)
266 		return -ENOMEM;
267 
268 	gnttab_init();
269 	if (!xen_initial_domain())
270 		xenbus_probe(NULL);
271 
272 	/*
273 	 * Making sure board specific code will not set up ops for
274 	 * cpu idle and cpu freq.
275 	 */
276 	disable_cpuidle();
277 	disable_cpufreq();
278 
279 	return 0;
280 }
281 core_initcall(xen_guest_init);
282 
283 static int __init xen_pm_init(void)
284 {
285 	if (!xen_domain())
286 		return -ENODEV;
287 
288 	pm_power_off = xen_power_off;
289 	arm_pm_restart = xen_restart;
290 
291 	return 0;
292 }
293 late_initcall(xen_pm_init);
294 
295 static irqreturn_t xen_arm_callback(int irq, void *arg)
296 {
297 	xen_hvm_evtchn_do_upcall();
298 	return IRQ_HANDLED;
299 }
300 
301 static int __init xen_init_events(void)
302 {
303 	if (!xen_domain() || xen_events_irq < 0)
304 		return -ENODEV;
305 
306 	xen_init_IRQ();
307 
308 	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
309 			"events", &xen_vcpu)) {
310 		pr_err("Error requesting IRQ %d\n", xen_events_irq);
311 		return -EINVAL;
312 	}
313 
314 	on_each_cpu(xen_percpu_init, NULL, 0);
315 
316 	return 0;
317 }
318 postcore_initcall(xen_init_events);
319 
320 /* In the hypervisor.S file. */
321 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
322 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
323 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
324 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
325 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
326 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
327 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
328 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
329 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
330 EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
331 EXPORT_SYMBOL_GPL(privcmd_call);
332