xref: /openbmc/linux/arch/arm/xen/enlighten.c (revision 97da55fc)
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 	int err = 0;
63 
64 	set_xen_guest_handle(xatp.idxs, &idx);
65 	set_xen_guest_handle(xatp.gpfns, &gpfn);
66 	set_xen_guest_handle(xatp.errs, &err);
67 
68 	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
69 	if (rc || err) {
70 		pr_warn("Failed to map pfn to mfn rc:%d:%d pfn:%lx mfn:%lx\n",
71 			rc, err, lpfn, fgmfn);
72 		return 1;
73 	}
74 	return 0;
75 }
76 
77 struct remap_data {
78 	xen_pfn_t fgmfn; /* foreign domain's gmfn */
79 	pgprot_t prot;
80 	domid_t  domid;
81 	struct vm_area_struct *vma;
82 	int index;
83 	struct page **pages;
84 	struct xen_remap_mfn_info *info;
85 };
86 
87 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
88 			void *data)
89 {
90 	struct remap_data *info = data;
91 	struct page *page = info->pages[info->index++];
92 	unsigned long pfn = page_to_pfn(page);
93 	pte_t pte = pfn_pte(pfn, info->prot);
94 
95 	if (map_foreign_page(pfn, info->fgmfn, info->domid))
96 		return -EFAULT;
97 	set_pte_at(info->vma->vm_mm, addr, ptep, pte);
98 
99 	return 0;
100 }
101 
102 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
103 			       unsigned long addr,
104 			       xen_pfn_t mfn, int nr,
105 			       pgprot_t prot, unsigned domid,
106 			       struct page **pages)
107 {
108 	int err;
109 	struct remap_data data;
110 
111 	/* TBD: Batching, current sole caller only does page at a time */
112 	if (nr > 1)
113 		return -EINVAL;
114 
115 	data.fgmfn = mfn;
116 	data.prot = prot;
117 	data.domid = domid;
118 	data.vma = vma;
119 	data.index = 0;
120 	data.pages = pages;
121 	err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
122 				  remap_pte_fn, &data);
123 	return err;
124 }
125 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
126 
127 int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
128 			       int nr, struct page **pages)
129 {
130 	int i;
131 
132 	for (i = 0; i < nr; i++) {
133 		struct xen_remove_from_physmap xrp;
134 		unsigned long rc, pfn;
135 
136 		pfn = page_to_pfn(pages[i]);
137 
138 		xrp.domid = DOMID_SELF;
139 		xrp.gpfn = pfn;
140 		rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
141 		if (rc) {
142 			pr_warn("Failed to unmap pfn:%lx rc:%ld\n",
143 				pfn, rc);
144 			return rc;
145 		}
146 	}
147 	return 0;
148 }
149 EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
150 
151 /*
152  * see Documentation/devicetree/bindings/arm/xen.txt for the
153  * documentation of the Xen Device Tree format.
154  */
155 #define GRANT_TABLE_PHYSADDR 0
156 static int __init xen_guest_init(void)
157 {
158 	struct xen_add_to_physmap xatp;
159 	static struct shared_info *shared_info_page = 0;
160 	struct device_node *node;
161 	int len;
162 	const char *s = NULL;
163 	const char *version = NULL;
164 	const char *xen_prefix = "xen,xen-";
165 	struct resource res;
166 
167 	node = of_find_compatible_node(NULL, NULL, "xen,xen");
168 	if (!node) {
169 		pr_debug("No Xen support\n");
170 		return 0;
171 	}
172 	s = of_get_property(node, "compatible", &len);
173 	if (strlen(xen_prefix) + 3  < len &&
174 			!strncmp(xen_prefix, s, strlen(xen_prefix)))
175 		version = s + strlen(xen_prefix);
176 	if (version == NULL) {
177 		pr_debug("Xen version not found\n");
178 		return 0;
179 	}
180 	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
181 		return 0;
182 	xen_hvm_resume_frames = res.start >> PAGE_SHIFT;
183 	xen_events_irq = irq_of_parse_and_map(node, 0);
184 	pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n",
185 			version, xen_events_irq, xen_hvm_resume_frames);
186 	xen_domain_type = XEN_HVM_DOMAIN;
187 
188 	xen_setup_features();
189 	if (xen_feature(XENFEAT_dom0))
190 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
191 	else
192 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
193 
194 	if (!shared_info_page)
195 		shared_info_page = (struct shared_info *)
196 			get_zeroed_page(GFP_KERNEL);
197 	if (!shared_info_page) {
198 		pr_err("not enough memory\n");
199 		return -ENOMEM;
200 	}
201 	xatp.domid = DOMID_SELF;
202 	xatp.idx = 0;
203 	xatp.space = XENMAPSPACE_shared_info;
204 	xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
205 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
206 		BUG();
207 
208 	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
209 
210 	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
211 	 * page, we use it in the event channel upcall and in some pvclock
212 	 * related functions. We don't need the vcpu_info placement
213 	 * optimizations because we don't use any pv_mmu or pv_irq op on
214 	 * HVM.
215 	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
216 	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
217 	 * for secondary CPUs as they are brought up. */
218 	per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
219 
220 	gnttab_init();
221 	if (!xen_initial_domain())
222 		xenbus_probe(NULL);
223 
224 	return 0;
225 }
226 core_initcall(xen_guest_init);
227 
228 static irqreturn_t xen_arm_callback(int irq, void *arg)
229 {
230 	xen_hvm_evtchn_do_upcall();
231 	return IRQ_HANDLED;
232 }
233 
234 static int __init xen_init_events(void)
235 {
236 	if (!xen_domain() || xen_events_irq < 0)
237 		return -ENODEV;
238 
239 	xen_init_IRQ();
240 
241 	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
242 			"events", xen_vcpu)) {
243 		pr_err("Error requesting IRQ %d\n", xen_events_irq);
244 		return -EINVAL;
245 	}
246 
247 	enable_percpu_irq(xen_events_irq, 0);
248 
249 	return 0;
250 }
251 postcore_initcall(xen_init_events);
252 
253 /* In the hypervisor.S file. */
254 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
255 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
256 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
257 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
258 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
259 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
260 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
261 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
262 EXPORT_SYMBOL_GPL(privcmd_call);
263