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1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/acpi.h>
4#include <linux/cpu.h>
5#include <linux/kexec.h>
6#include <linux/memblock.h>
7#include <linux/virtio_anchor.h>
8
9#include <xen/features.h>
10#include <xen/events.h>
11#include <xen/hvm.h>
12#include <xen/interface/hvm/hvm_op.h>
13#include <xen/interface/memory.h>
14
15#include <asm/apic.h>
16#include <asm/cpu.h>
17#include <asm/smp.h>
18#include <asm/io_apic.h>
19#include <asm/reboot.h>
20#include <asm/setup.h>
21#include <asm/idtentry.h>
22#include <asm/hypervisor.h>
23#include <asm/e820/api.h>
24#include <asm/early_ioremap.h>
25
26#include <asm/xen/cpuid.h>
27#include <asm/xen/hypervisor.h>
28#include <asm/xen/page.h>
29
30#include "xen-ops.h"
31#include "mmu.h"
32#include "smp.h"
33
34static unsigned long shared_info_pfn;
35
36__ro_after_init bool xen_percpu_upcall;
37EXPORT_SYMBOL_GPL(xen_percpu_upcall);
38
39void xen_hvm_init_shared_info(void)
40{
41 struct xen_add_to_physmap xatp;
42
43 xatp.domid = DOMID_SELF;
44 xatp.idx = 0;
45 xatp.space = XENMAPSPACE_shared_info;
46 xatp.gpfn = shared_info_pfn;
47 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
48 BUG();
49}
50
51static void __init reserve_shared_info(void)
52{
53 u64 pa;
54
55 /*
56 * Search for a free page starting at 4kB physical address.
57 * Low memory is preferred to avoid an EPT large page split up
58 * by the mapping.
59 * Starting below X86_RESERVE_LOW (usually 64kB) is fine as
60 * the BIOS used for HVM guests is well behaved and won't
61 * clobber memory other than the first 4kB.
62 */
63 for (pa = PAGE_SIZE;
64 !e820__mapped_all(pa, pa + PAGE_SIZE, E820_TYPE_RAM) ||
65 memblock_is_reserved(pa);
66 pa += PAGE_SIZE)
67 ;
68
69 shared_info_pfn = PHYS_PFN(pa);
70
71 memblock_reserve(pa, PAGE_SIZE);
72 HYPERVISOR_shared_info = early_memremap(pa, PAGE_SIZE);
73}
74
75static void __init xen_hvm_init_mem_mapping(void)
76{
77 early_memunmap(HYPERVISOR_shared_info, PAGE_SIZE);
78 HYPERVISOR_shared_info = __va(PFN_PHYS(shared_info_pfn));
79
80 /*
81 * The virtual address of the shared_info page has changed, so
82 * the vcpu_info pointer for VCPU 0 is now stale.
83 *
84 * The prepare_boot_cpu callback will re-initialize it via
85 * xen_vcpu_setup, but we can't rely on that to be called for
86 * old Xen versions (xen_have_vector_callback == 0).
87 *
88 * It is, in any case, bad to have a stale vcpu_info pointer
89 * so reset it now.
90 */
91 xen_vcpu_info_reset(0);
92}
93
94static void __init init_hvm_pv_info(void)
95{
96 int major, minor;
97 uint32_t eax, ebx, ecx, edx, base;
98
99 base = xen_cpuid_base();
100 eax = cpuid_eax(base + 1);
101
102 major = eax >> 16;
103 minor = eax & 0xffff;
104 printk(KERN_INFO "Xen version %d.%d.\n", major, minor);
105
106 xen_domain_type = XEN_HVM_DOMAIN;
107
108 /* PVH set up hypercall page in xen_prepare_pvh(). */
109 if (xen_pvh_domain())
110 pv_info.name = "Xen PVH";
111 else {
112 u64 pfn;
113 uint32_t msr;
114
115 pv_info.name = "Xen HVM";
116 msr = cpuid_ebx(base + 2);
117 pfn = __pa(hypercall_page);
118 wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
119 }
120
121 xen_setup_features();
122
123 cpuid(base + 4, &eax, &ebx, &ecx, &edx);
124 if (eax & XEN_HVM_CPUID_VCPU_ID_PRESENT)
125 this_cpu_write(xen_vcpu_id, ebx);
126 else
127 this_cpu_write(xen_vcpu_id, smp_processor_id());
128}
129
130DEFINE_IDTENTRY_SYSVEC(sysvec_xen_hvm_callback)
131{
132 struct pt_regs *old_regs = set_irq_regs(regs);
133
134 if (xen_percpu_upcall)
135 ack_APIC_irq();
136
137 inc_irq_stat(irq_hv_callback_count);
138
139 xen_hvm_evtchn_do_upcall();
140
141 set_irq_regs(old_regs);
142}
143
144#ifdef CONFIG_KEXEC_CORE
145static void xen_hvm_shutdown(void)
146{
147 native_machine_shutdown();
148 if (kexec_in_progress)
149 xen_reboot(SHUTDOWN_soft_reset);
150}
151
152static void xen_hvm_crash_shutdown(struct pt_regs *regs)
153{
154 native_machine_crash_shutdown(regs);
155 xen_reboot(SHUTDOWN_soft_reset);
156}
157#endif
158
159static int xen_cpu_up_prepare_hvm(unsigned int cpu)
160{
161 int rc = 0;
162
163 /*
164 * This can happen if CPU was offlined earlier and
165 * offlining timed out in common_cpu_die().
166 */
167 if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
168 xen_smp_intr_free(cpu);
169 xen_uninit_lock_cpu(cpu);
170 }
171
172 if (cpu_acpi_id(cpu) != U32_MAX)
173 per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu);
174 else
175 per_cpu(xen_vcpu_id, cpu) = cpu;
176 xen_vcpu_setup(cpu);
177 if (!xen_have_vector_callback)
178 return 0;
179
180 if (xen_percpu_upcall) {
181 rc = xen_set_upcall_vector(cpu);
182 if (rc) {
183 WARN(1, "HVMOP_set_evtchn_upcall_vector"
184 " for CPU %d failed: %d\n", cpu, rc);
185 return rc;
186 }
187 }
188
189 if (xen_feature(XENFEAT_hvm_safe_pvclock))
190 xen_setup_timer(cpu);
191
192 rc = xen_smp_intr_init(cpu);
193 if (rc) {
194 WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n",
195 cpu, rc);
196 }
197 return rc;
198}
199
200static int xen_cpu_dead_hvm(unsigned int cpu)
201{
202 xen_smp_intr_free(cpu);
203
204 if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
205 xen_teardown_timer(cpu);
206 return 0;
207}
208
209static void __init xen_hvm_guest_init(void)
210{
211 if (xen_pv_domain())
212 return;
213
214 if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
215 virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc);
216
217 init_hvm_pv_info();
218
219 reserve_shared_info();
220 xen_hvm_init_shared_info();
221
222 /*
223 * xen_vcpu is a pointer to the vcpu_info struct in the shared_info
224 * page, we use it in the event channel upcall and in some pvclock
225 * related functions.
226 */
227 xen_vcpu_info_reset(0);
228
229 xen_panic_handler_init();
230
231 xen_hvm_smp_init();
232 WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm));
233 xen_unplug_emulated_devices();
234 x86_init.irqs.intr_init = xen_init_IRQ;
235 xen_hvm_init_time_ops();
236 xen_hvm_init_mmu_ops();
237
238#ifdef CONFIG_KEXEC_CORE
239 machine_ops.shutdown = xen_hvm_shutdown;
240 machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
241#endif
242}
243
244static __init int xen_parse_nopv(char *arg)
245{
246 pr_notice("\"xen_nopv\" is deprecated, please use \"nopv\" instead\n");
247
248 if (xen_cpuid_base())
249 nopv = true;
250 return 0;
251}
252early_param("xen_nopv", xen_parse_nopv);
253
254static __init int xen_parse_no_vector_callback(char *arg)
255{
256 xen_have_vector_callback = false;
257 return 0;
258}
259early_param("xen_no_vector_callback", xen_parse_no_vector_callback);
260
261static __init bool xen_x2apic_available(void)
262{
263 return x2apic_supported();
264}
265
266static bool __init msi_ext_dest_id(void)
267{
268 return cpuid_eax(xen_cpuid_base() + 4) & XEN_HVM_CPUID_EXT_DEST_ID;
269}
270
271static __init void xen_hvm_guest_late_init(void)
272{
273#ifdef CONFIG_XEN_PVH
274 /* Test for PVH domain (PVH boot path taken overrides ACPI flags). */
275 if (!xen_pvh &&
276 (x86_platform.legacy.rtc || !x86_platform.legacy.no_vga))
277 return;
278
279 /* PVH detected. */
280 xen_pvh = true;
281
282 if (nopv)
283 panic("\"nopv\" and \"xen_nopv\" parameters are unsupported in PVH guest.");
284
285 /* Make sure we don't fall back to (default) ACPI_IRQ_MODEL_PIC. */
286 if (!nr_ioapics && acpi_irq_model == ACPI_IRQ_MODEL_PIC)
287 acpi_irq_model = ACPI_IRQ_MODEL_PLATFORM;
288
289 machine_ops.emergency_restart = xen_emergency_restart;
290 pv_info.name = "Xen PVH";
291#endif
292}
293
294static uint32_t __init xen_platform_hvm(void)
295{
296 uint32_t xen_domain = xen_cpuid_base();
297 struct x86_hyper_init *h = &x86_hyper_xen_hvm.init;
298
299 if (xen_pv_domain())
300 return 0;
301
302 if (xen_pvh_domain() && nopv) {
303 /* Guest booting via the Xen-PVH boot entry goes here */
304 pr_info("\"nopv\" parameter is ignored in PVH guest\n");
305 nopv = false;
306 } else if (nopv && xen_domain) {
307 /*
308 * Guest booting via normal boot entry (like via grub2) goes
309 * here.
310 *
311 * Use interface functions for bare hardware if nopv,
312 * xen_hvm_guest_late_init is an exception as we need to
313 * detect PVH and panic there.
314 */
315 h->init_platform = x86_init_noop;
316 h->x2apic_available = bool_x86_init_noop;
317 h->init_mem_mapping = x86_init_noop;
318 h->init_after_bootmem = x86_init_noop;
319 h->guest_late_init = xen_hvm_guest_late_init;
320 x86_hyper_xen_hvm.runtime.pin_vcpu = x86_op_int_noop;
321 }
322 return xen_domain;
323}
324
325struct hypervisor_x86 x86_hyper_xen_hvm __initdata = {
326 .name = "Xen HVM",
327 .detect = xen_platform_hvm,
328 .type = X86_HYPER_XEN_HVM,
329 .init.init_platform = xen_hvm_guest_init,
330 .init.x2apic_available = xen_x2apic_available,
331 .init.init_mem_mapping = xen_hvm_init_mem_mapping,
332 .init.guest_late_init = xen_hvm_guest_late_init,
333 .init.msi_ext_dest_id = msi_ext_dest_id,
334 .runtime.pin_vcpu = xen_pin_vcpu,
335 .ignore_nopv = true,
336};
1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/acpi.h>
4#include <linux/cpu.h>
5#include <linux/kexec.h>
6#include <linux/memblock.h>
7
8#include <xen/features.h>
9#include <xen/events.h>
10#include <xen/interface/memory.h>
11
12#include <asm/cpu.h>
13#include <asm/smp.h>
14#include <asm/reboot.h>
15#include <asm/setup.h>
16#include <asm/hypervisor.h>
17#include <asm/e820/api.h>
18#include <asm/early_ioremap.h>
19
20#include <asm/xen/cpuid.h>
21#include <asm/xen/hypervisor.h>
22#include <asm/xen/page.h>
23
24#include "xen-ops.h"
25#include "mmu.h"
26#include "smp.h"
27
28static unsigned long shared_info_pfn;
29
30void xen_hvm_init_shared_info(void)
31{
32 struct xen_add_to_physmap xatp;
33
34 xatp.domid = DOMID_SELF;
35 xatp.idx = 0;
36 xatp.space = XENMAPSPACE_shared_info;
37 xatp.gpfn = shared_info_pfn;
38 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
39 BUG();
40}
41
42static void __init reserve_shared_info(void)
43{
44 u64 pa;
45
46 /*
47 * Search for a free page starting at 4kB physical address.
48 * Low memory is preferred to avoid an EPT large page split up
49 * by the mapping.
50 * Starting below X86_RESERVE_LOW (usually 64kB) is fine as
51 * the BIOS used for HVM guests is well behaved and won't
52 * clobber memory other than the first 4kB.
53 */
54 for (pa = PAGE_SIZE;
55 !e820__mapped_all(pa, pa + PAGE_SIZE, E820_TYPE_RAM) ||
56 memblock_is_reserved(pa);
57 pa += PAGE_SIZE)
58 ;
59
60 shared_info_pfn = PHYS_PFN(pa);
61
62 memblock_reserve(pa, PAGE_SIZE);
63 HYPERVISOR_shared_info = early_memremap(pa, PAGE_SIZE);
64}
65
66static void __init xen_hvm_init_mem_mapping(void)
67{
68 early_memunmap(HYPERVISOR_shared_info, PAGE_SIZE);
69 HYPERVISOR_shared_info = __va(PFN_PHYS(shared_info_pfn));
70
71 /*
72 * The virtual address of the shared_info page has changed, so
73 * the vcpu_info pointer for VCPU 0 is now stale.
74 *
75 * The prepare_boot_cpu callback will re-initialize it via
76 * xen_vcpu_setup, but we can't rely on that to be called for
77 * old Xen versions (xen_have_vector_callback == 0).
78 *
79 * It is, in any case, bad to have a stale vcpu_info pointer
80 * so reset it now.
81 */
82 xen_vcpu_info_reset(0);
83}
84
85static void __init init_hvm_pv_info(void)
86{
87 int major, minor;
88 uint32_t eax, ebx, ecx, edx, base;
89
90 base = xen_cpuid_base();
91 eax = cpuid_eax(base + 1);
92
93 major = eax >> 16;
94 minor = eax & 0xffff;
95 printk(KERN_INFO "Xen version %d.%d.\n", major, minor);
96
97 xen_domain_type = XEN_HVM_DOMAIN;
98
99 /* PVH set up hypercall page in xen_prepare_pvh(). */
100 if (xen_pvh_domain())
101 pv_info.name = "Xen PVH";
102 else {
103 u64 pfn;
104 uint32_t msr;
105
106 pv_info.name = "Xen HVM";
107 msr = cpuid_ebx(base + 2);
108 pfn = __pa(hypercall_page);
109 wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
110 }
111
112 xen_setup_features();
113
114 cpuid(base + 4, &eax, &ebx, &ecx, &edx);
115 if (eax & XEN_HVM_CPUID_VCPU_ID_PRESENT)
116 this_cpu_write(xen_vcpu_id, ebx);
117 else
118 this_cpu_write(xen_vcpu_id, smp_processor_id());
119}
120
121#ifdef CONFIG_KEXEC_CORE
122static void xen_hvm_shutdown(void)
123{
124 native_machine_shutdown();
125 if (kexec_in_progress)
126 xen_reboot(SHUTDOWN_soft_reset);
127}
128
129static void xen_hvm_crash_shutdown(struct pt_regs *regs)
130{
131 native_machine_crash_shutdown(regs);
132 xen_reboot(SHUTDOWN_soft_reset);
133}
134#endif
135
136static int xen_cpu_up_prepare_hvm(unsigned int cpu)
137{
138 int rc = 0;
139
140 /*
141 * This can happen if CPU was offlined earlier and
142 * offlining timed out in common_cpu_die().
143 */
144 if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
145 xen_smp_intr_free(cpu);
146 xen_uninit_lock_cpu(cpu);
147 }
148
149 if (cpu_acpi_id(cpu) != U32_MAX)
150 per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu);
151 else
152 per_cpu(xen_vcpu_id, cpu) = cpu;
153 rc = xen_vcpu_setup(cpu);
154 if (rc)
155 return rc;
156
157 if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
158 xen_setup_timer(cpu);
159
160 rc = xen_smp_intr_init(cpu);
161 if (rc) {
162 WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n",
163 cpu, rc);
164 }
165 return rc;
166}
167
168static int xen_cpu_dead_hvm(unsigned int cpu)
169{
170 xen_smp_intr_free(cpu);
171
172 if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
173 xen_teardown_timer(cpu);
174
175 return 0;
176}
177
178static void __init xen_hvm_guest_init(void)
179{
180 if (xen_pv_domain())
181 return;
182
183 init_hvm_pv_info();
184
185 reserve_shared_info();
186 xen_hvm_init_shared_info();
187
188 /*
189 * xen_vcpu is a pointer to the vcpu_info struct in the shared_info
190 * page, we use it in the event channel upcall and in some pvclock
191 * related functions.
192 */
193 xen_vcpu_info_reset(0);
194
195 xen_panic_handler_init();
196
197 if (xen_feature(XENFEAT_hvm_callback_vector))
198 xen_have_vector_callback = 1;
199
200 xen_hvm_smp_init();
201 WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm));
202 xen_unplug_emulated_devices();
203 x86_init.irqs.intr_init = xen_init_IRQ;
204 xen_hvm_init_time_ops();
205 xen_hvm_init_mmu_ops();
206
207#ifdef CONFIG_KEXEC_CORE
208 machine_ops.shutdown = xen_hvm_shutdown;
209 machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
210#endif
211}
212
213static __init int xen_parse_nopv(char *arg)
214{
215 pr_notice("\"xen_nopv\" is deprecated, please use \"nopv\" instead\n");
216
217 if (xen_cpuid_base())
218 nopv = true;
219 return 0;
220}
221early_param("xen_nopv", xen_parse_nopv);
222
223bool __init xen_hvm_need_lapic(void)
224{
225 if (xen_pv_domain())
226 return false;
227 if (!xen_hvm_domain())
228 return false;
229 if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback)
230 return false;
231 return true;
232}
233
234static __init void xen_hvm_guest_late_init(void)
235{
236#ifdef CONFIG_XEN_PVH
237 /* Test for PVH domain (PVH boot path taken overrides ACPI flags). */
238 if (!xen_pvh &&
239 (x86_platform.legacy.rtc || !x86_platform.legacy.no_vga))
240 return;
241
242 /* PVH detected. */
243 xen_pvh = true;
244
245 if (nopv)
246 panic("\"nopv\" and \"xen_nopv\" parameters are unsupported in PVH guest.");
247
248 /* Make sure we don't fall back to (default) ACPI_IRQ_MODEL_PIC. */
249 if (!nr_ioapics && acpi_irq_model == ACPI_IRQ_MODEL_PIC)
250 acpi_irq_model = ACPI_IRQ_MODEL_PLATFORM;
251
252 machine_ops.emergency_restart = xen_emergency_restart;
253 pv_info.name = "Xen PVH";
254#endif
255}
256
257static uint32_t __init xen_platform_hvm(void)
258{
259 uint32_t xen_domain = xen_cpuid_base();
260 struct x86_hyper_init *h = &x86_hyper_xen_hvm.init;
261
262 if (xen_pv_domain())
263 return 0;
264
265 if (xen_pvh_domain() && nopv) {
266 /* Guest booting via the Xen-PVH boot entry goes here */
267 pr_info("\"nopv\" parameter is ignored in PVH guest\n");
268 nopv = false;
269 } else if (nopv && xen_domain) {
270 /*
271 * Guest booting via normal boot entry (like via grub2) goes
272 * here.
273 *
274 * Use interface functions for bare hardware if nopv,
275 * xen_hvm_guest_late_init is an exception as we need to
276 * detect PVH and panic there.
277 */
278 h->init_platform = x86_init_noop;
279 h->x2apic_available = bool_x86_init_noop;
280 h->init_mem_mapping = x86_init_noop;
281 h->init_after_bootmem = x86_init_noop;
282 h->guest_late_init = xen_hvm_guest_late_init;
283 x86_hyper_xen_hvm.runtime.pin_vcpu = x86_op_int_noop;
284 }
285 return xen_domain;
286}
287
288struct hypervisor_x86 x86_hyper_xen_hvm __initdata = {
289 .name = "Xen HVM",
290 .detect = xen_platform_hvm,
291 .type = X86_HYPER_XEN_HVM,
292 .init.init_platform = xen_hvm_guest_init,
293 .init.x2apic_available = xen_x2apic_para_available,
294 .init.init_mem_mapping = xen_hvm_init_mem_mapping,
295 .init.guest_late_init = xen_hvm_guest_late_init,
296 .runtime.pin_vcpu = xen_pin_vcpu,
297 .ignore_nopv = true,
298};