xref: /openbmc/linux/arch/arm/xen/enlighten.c (revision f35e839a)
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 int __init xen_secondary_init(unsigned int cpu)
156 {
157 	struct vcpu_register_vcpu_info info;
158 	struct vcpu_info *vcpup;
159 	int err;
160 
161 	pr_info("Xen: initializing cpu%d\n", cpu);
162 	vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
163 
164 	info.mfn = __pa(vcpup) >> PAGE_SHIFT;
165 	info.offset = offset_in_page(vcpup);
166 
167 	err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
168 	if (err) {
169 		pr_debug("register_vcpu_info failed: err=%d\n", err);
170 	} else {
171 		/* This cpu is using the registered vcpu info, even if
172 		   later ones fail to. */
173 		per_cpu(xen_vcpu, cpu) = vcpup;
174 	}
175 	return 0;
176 }
177 
178 static void xen_restart(char str, 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 	int i;
212 
213 	node = of_find_compatible_node(NULL, NULL, "xen,xen");
214 	if (!node) {
215 		pr_debug("No Xen support\n");
216 		return 0;
217 	}
218 	s = of_get_property(node, "compatible", &len);
219 	if (strlen(xen_prefix) + 3  < len &&
220 			!strncmp(xen_prefix, s, strlen(xen_prefix)))
221 		version = s + strlen(xen_prefix);
222 	if (version == NULL) {
223 		pr_debug("Xen version not found\n");
224 		return 0;
225 	}
226 	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
227 		return 0;
228 	xen_hvm_resume_frames = res.start >> PAGE_SHIFT;
229 	xen_events_irq = irq_of_parse_and_map(node, 0);
230 	pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n",
231 			version, xen_events_irq, xen_hvm_resume_frames);
232 	xen_domain_type = XEN_HVM_DOMAIN;
233 
234 	xen_setup_features();
235 	if (xen_feature(XENFEAT_dom0))
236 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
237 	else
238 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
239 
240 	if (!shared_info_page)
241 		shared_info_page = (struct shared_info *)
242 			get_zeroed_page(GFP_KERNEL);
243 	if (!shared_info_page) {
244 		pr_err("not enough memory\n");
245 		return -ENOMEM;
246 	}
247 	xatp.domid = DOMID_SELF;
248 	xatp.idx = 0;
249 	xatp.space = XENMAPSPACE_shared_info;
250 	xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
251 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
252 		BUG();
253 
254 	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
255 
256 	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
257 	 * page, we use it in the event channel upcall and in some pvclock
258 	 * related functions.
259 	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
260 	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
261 	 * for secondary CPUs as they are brought up.
262 	 * For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
263 	 */
264 	xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info),
265 			                       sizeof(struct vcpu_info));
266 	if (xen_vcpu_info == NULL)
267 		return -ENOMEM;
268 	for_each_online_cpu(i)
269 		xen_secondary_init(i);
270 
271 	gnttab_init();
272 	if (!xen_initial_domain())
273 		xenbus_probe(NULL);
274 
275 	pm_power_off = xen_power_off;
276 	arm_pm_restart = xen_restart;
277 
278 	return 0;
279 }
280 core_initcall(xen_guest_init);
281 
282 static irqreturn_t xen_arm_callback(int irq, void *arg)
283 {
284 	xen_hvm_evtchn_do_upcall();
285 	return IRQ_HANDLED;
286 }
287 
288 static __init void xen_percpu_enable_events(void *unused)
289 {
290 	enable_percpu_irq(xen_events_irq, 0);
291 }
292 
293 static int __init xen_init_events(void)
294 {
295 	if (!xen_domain() || xen_events_irq < 0)
296 		return -ENODEV;
297 
298 	xen_init_IRQ();
299 
300 	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
301 			"events", &xen_vcpu)) {
302 		pr_err("Error requesting IRQ %d\n", xen_events_irq);
303 		return -EINVAL;
304 	}
305 
306 	on_each_cpu(xen_percpu_enable_events, NULL, 0);
307 
308 	return 0;
309 }
310 postcore_initcall(xen_init_events);
311 
312 /* In the hypervisor.S file. */
313 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
314 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
315 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
316 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
317 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
318 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
319 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
320 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
321 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
322 EXPORT_SYMBOL_GPL(privcmd_call);
323