1 // SPDX-License-Identifier: GPL-2.0-only 2 #include <xen/xen.h> 3 #include <xen/events.h> 4 #include <xen/grant_table.h> 5 #include <xen/hvm.h> 6 #include <xen/interface/vcpu.h> 7 #include <xen/interface/xen.h> 8 #include <xen/interface/memory.h> 9 #include <xen/interface/hvm/params.h> 10 #include <xen/features.h> 11 #include <xen/platform_pci.h> 12 #include <xen/xenbus.h> 13 #include <xen/page.h> 14 #include <xen/interface/sched.h> 15 #include <xen/xen-ops.h> 16 #include <asm/xen/hypervisor.h> 17 #include <asm/xen/hypercall.h> 18 #include <asm/system_misc.h> 19 #include <asm/efi.h> 20 #include <linux/interrupt.h> 21 #include <linux/irqreturn.h> 22 #include <linux/module.h> 23 #include <linux/of.h> 24 #include <linux/of_fdt.h> 25 #include <linux/of_irq.h> 26 #include <linux/of_address.h> 27 #include <linux/cpuidle.h> 28 #include <linux/cpufreq.h> 29 #include <linux/cpu.h> 30 #include <linux/console.h> 31 #include <linux/pvclock_gtod.h> 32 #include <linux/reboot.h> 33 #include <linux/time64.h> 34 #include <linux/timekeeping.h> 35 #include <linux/timekeeper_internal.h> 36 #include <linux/acpi.h> 37 38 #include <linux/mm.h> 39 40 static struct start_info _xen_start_info; 41 struct start_info *xen_start_info = &_xen_start_info; 42 EXPORT_SYMBOL(xen_start_info); 43 44 enum xen_domain_type xen_domain_type = XEN_NATIVE; 45 EXPORT_SYMBOL(xen_domain_type); 46 47 struct shared_info xen_dummy_shared_info; 48 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; 49 50 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); 51 static struct vcpu_info __percpu *xen_vcpu_info; 52 53 /* Linux <-> Xen vCPU id mapping */ 54 DEFINE_PER_CPU(uint32_t, xen_vcpu_id); 55 EXPORT_PER_CPU_SYMBOL(xen_vcpu_id); 56 57 /* These are unused until we support booting "pre-ballooned" */ 58 unsigned long xen_released_pages; 59 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; 60 61 static __read_mostly unsigned int xen_events_irq; 62 63 uint32_t xen_start_flags; 64 EXPORT_SYMBOL(xen_start_flags); 65 66 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, 67 int nr, struct page **pages) 68 { 69 return xen_xlate_unmap_gfn_range(vma, nr, pages); 70 } 71 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); 72 73 static void xen_read_wallclock(struct timespec64 *ts) 74 { 75 u32 version; 76 struct timespec64 now, ts_monotonic; 77 struct shared_info *s = HYPERVISOR_shared_info; 78 struct pvclock_wall_clock *wall_clock = &(s->wc); 79 80 /* get wallclock at system boot */ 81 do { 82 version = wall_clock->version; 83 rmb(); /* fetch version before time */ 84 now.tv_sec = ((uint64_t)wall_clock->sec_hi << 32) | wall_clock->sec; 85 now.tv_nsec = wall_clock->nsec; 86 rmb(); /* fetch time before checking version */ 87 } while ((wall_clock->version & 1) || (version != wall_clock->version)); 88 89 /* time since system boot */ 90 ktime_get_ts64(&ts_monotonic); 91 *ts = timespec64_add(now, ts_monotonic); 92 } 93 94 static int xen_pvclock_gtod_notify(struct notifier_block *nb, 95 unsigned long was_set, void *priv) 96 { 97 /* Protected by the calling core code serialization */ 98 static struct timespec64 next_sync; 99 100 struct xen_platform_op op; 101 struct timespec64 now, system_time; 102 struct timekeeper *tk = priv; 103 104 now.tv_sec = tk->xtime_sec; 105 now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); 106 system_time = timespec64_add(now, tk->wall_to_monotonic); 107 108 /* 109 * We only take the expensive HV call when the clock was set 110 * or when the 11 minutes RTC synchronization time elapsed. 111 */ 112 if (!was_set && timespec64_compare(&now, &next_sync) < 0) 113 return NOTIFY_OK; 114 115 op.cmd = XENPF_settime64; 116 op.u.settime64.mbz = 0; 117 op.u.settime64.secs = now.tv_sec; 118 op.u.settime64.nsecs = now.tv_nsec; 119 op.u.settime64.system_time = timespec64_to_ns(&system_time); 120 (void)HYPERVISOR_platform_op(&op); 121 122 /* 123 * Move the next drift compensation time 11 minutes 124 * ahead. That's emulating the sync_cmos_clock() update for 125 * the hardware RTC. 126 */ 127 next_sync = now; 128 next_sync.tv_sec += 11 * 60; 129 130 return NOTIFY_OK; 131 } 132 133 static struct notifier_block xen_pvclock_gtod_notifier = { 134 .notifier_call = xen_pvclock_gtod_notify, 135 }; 136 137 static int xen_starting_cpu(unsigned int cpu) 138 { 139 struct vcpu_register_vcpu_info info; 140 struct vcpu_info *vcpup; 141 int err; 142 143 /* 144 * VCPUOP_register_vcpu_info cannot be called twice for the same 145 * vcpu, so if vcpu_info is already registered, just get out. This 146 * can happen with cpu-hotplug. 147 */ 148 if (per_cpu(xen_vcpu, cpu) != NULL) 149 goto after_register_vcpu_info; 150 151 pr_info("Xen: initializing cpu%d\n", cpu); 152 vcpup = per_cpu_ptr(xen_vcpu_info, cpu); 153 154 info.mfn = percpu_to_gfn(vcpup); 155 info.offset = xen_offset_in_page(vcpup); 156 157 err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, xen_vcpu_nr(cpu), 158 &info); 159 BUG_ON(err); 160 per_cpu(xen_vcpu, cpu) = vcpup; 161 162 if (!xen_kernel_unmapped_at_usr()) 163 xen_setup_runstate_info(cpu); 164 165 after_register_vcpu_info: 166 enable_percpu_irq(xen_events_irq, 0); 167 return 0; 168 } 169 170 static int xen_dying_cpu(unsigned int cpu) 171 { 172 disable_percpu_irq(xen_events_irq); 173 return 0; 174 } 175 176 void xen_reboot(int reason) 177 { 178 struct sched_shutdown r = { .reason = reason }; 179 int rc; 180 181 rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r); 182 BUG_ON(rc); 183 } 184 185 static int xen_restart(struct notifier_block *nb, unsigned long action, 186 void *data) 187 { 188 xen_reboot(SHUTDOWN_reboot); 189 190 return NOTIFY_DONE; 191 } 192 193 static struct notifier_block xen_restart_nb = { 194 .notifier_call = xen_restart, 195 .priority = 192, 196 }; 197 198 static void xen_power_off(void) 199 { 200 xen_reboot(SHUTDOWN_poweroff); 201 } 202 203 static irqreturn_t xen_arm_callback(int irq, void *arg) 204 { 205 xen_hvm_evtchn_do_upcall(); 206 return IRQ_HANDLED; 207 } 208 209 static __initdata struct { 210 const char *compat; 211 const char *prefix; 212 const char *version; 213 bool found; 214 } hyper_node = {"xen,xen", "xen,xen-", NULL, false}; 215 216 static int __init fdt_find_hyper_node(unsigned long node, const char *uname, 217 int depth, void *data) 218 { 219 const void *s = NULL; 220 int len; 221 222 if (depth != 1 || strcmp(uname, "hypervisor") != 0) 223 return 0; 224 225 if (of_flat_dt_is_compatible(node, hyper_node.compat)) 226 hyper_node.found = true; 227 228 s = of_get_flat_dt_prop(node, "compatible", &len); 229 if (strlen(hyper_node.prefix) + 3 < len && 230 !strncmp(hyper_node.prefix, s, strlen(hyper_node.prefix))) 231 hyper_node.version = s + strlen(hyper_node.prefix); 232 233 /* 234 * Check if Xen supports EFI by checking whether there is the 235 * "/hypervisor/uefi" node in DT. If so, runtime services are available 236 * through proxy functions (e.g. in case of Xen dom0 EFI implementation 237 * they call special hypercall which executes relevant EFI functions) 238 * and that is why they are always enabled. 239 */ 240 if (IS_ENABLED(CONFIG_XEN_EFI)) { 241 if ((of_get_flat_dt_subnode_by_name(node, "uefi") > 0) && 242 !efi_runtime_disabled()) 243 set_bit(EFI_RUNTIME_SERVICES, &efi.flags); 244 } 245 246 return 0; 247 } 248 249 /* 250 * see Documentation/devicetree/bindings/arm/xen.txt for the 251 * documentation of the Xen Device Tree format. 252 */ 253 void __init xen_early_init(void) 254 { 255 of_scan_flat_dt(fdt_find_hyper_node, NULL); 256 if (!hyper_node.found) { 257 pr_debug("No Xen support\n"); 258 return; 259 } 260 261 if (hyper_node.version == NULL) { 262 pr_debug("Xen version not found\n"); 263 return; 264 } 265 266 pr_info("Xen %s support found\n", hyper_node.version); 267 268 xen_domain_type = XEN_HVM_DOMAIN; 269 270 xen_setup_features(); 271 272 if (xen_feature(XENFEAT_dom0)) 273 xen_start_flags |= SIF_INITDOMAIN|SIF_PRIVILEGED; 274 275 if (!console_set_on_cmdline && !xen_initial_domain()) 276 add_preferred_console("hvc", 0, NULL); 277 } 278 279 static void __init xen_acpi_guest_init(void) 280 { 281 #ifdef CONFIG_ACPI 282 struct xen_hvm_param a; 283 int interrupt, trigger, polarity; 284 285 a.domid = DOMID_SELF; 286 a.index = HVM_PARAM_CALLBACK_IRQ; 287 288 if (HYPERVISOR_hvm_op(HVMOP_get_param, &a) 289 || (a.value >> 56) != HVM_PARAM_CALLBACK_TYPE_PPI) { 290 xen_events_irq = 0; 291 return; 292 } 293 294 interrupt = a.value & 0xff; 295 trigger = ((a.value >> 8) & 0x1) ? ACPI_EDGE_SENSITIVE 296 : ACPI_LEVEL_SENSITIVE; 297 polarity = ((a.value >> 8) & 0x2) ? ACPI_ACTIVE_LOW 298 : ACPI_ACTIVE_HIGH; 299 xen_events_irq = acpi_register_gsi(NULL, interrupt, trigger, polarity); 300 #endif 301 } 302 303 static void __init xen_dt_guest_init(void) 304 { 305 struct device_node *xen_node; 306 307 xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); 308 if (!xen_node) { 309 pr_err("Xen support was detected before, but it has disappeared\n"); 310 return; 311 } 312 313 xen_events_irq = irq_of_parse_and_map(xen_node, 0); 314 } 315 316 static int __init xen_guest_init(void) 317 { 318 struct xen_add_to_physmap xatp; 319 struct shared_info *shared_info_page = NULL; 320 int cpu; 321 322 if (!xen_domain()) 323 return 0; 324 325 if (!acpi_disabled) 326 xen_acpi_guest_init(); 327 else 328 xen_dt_guest_init(); 329 330 if (!xen_events_irq) { 331 pr_err("Xen event channel interrupt not found\n"); 332 return -ENODEV; 333 } 334 335 /* 336 * The fdt parsing codes have set EFI_RUNTIME_SERVICES if Xen EFI 337 * parameters are found. Force enable runtime services. 338 */ 339 if (efi_enabled(EFI_RUNTIME_SERVICES)) 340 xen_efi_runtime_setup(); 341 342 shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL); 343 344 if (!shared_info_page) { 345 pr_err("not enough memory\n"); 346 return -ENOMEM; 347 } 348 xatp.domid = DOMID_SELF; 349 xatp.idx = 0; 350 xatp.space = XENMAPSPACE_shared_info; 351 xatp.gpfn = virt_to_gfn(shared_info_page); 352 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) 353 BUG(); 354 355 HYPERVISOR_shared_info = (struct shared_info *)shared_info_page; 356 357 /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info 358 * page, we use it in the event channel upcall and in some pvclock 359 * related functions. 360 * The shared info contains exactly 1 CPU (the boot CPU). The guest 361 * is required to use VCPUOP_register_vcpu_info to place vcpu info 362 * for secondary CPUs as they are brought up. 363 * For uniformity we use VCPUOP_register_vcpu_info even on cpu0. 364 */ 365 xen_vcpu_info = alloc_percpu(struct vcpu_info); 366 if (xen_vcpu_info == NULL) 367 return -ENOMEM; 368 369 /* Direct vCPU id mapping for ARM guests. */ 370 for_each_possible_cpu(cpu) 371 per_cpu(xen_vcpu_id, cpu) = cpu; 372 373 xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); 374 if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, 375 &xen_auto_xlat_grant_frames.vaddr, 376 xen_auto_xlat_grant_frames.count)) { 377 free_percpu(xen_vcpu_info); 378 return -ENOMEM; 379 } 380 gnttab_init(); 381 382 /* 383 * Making sure board specific code will not set up ops for 384 * cpu idle and cpu freq. 385 */ 386 disable_cpuidle(); 387 disable_cpufreq(); 388 389 xen_init_IRQ(); 390 391 if (request_percpu_irq(xen_events_irq, xen_arm_callback, 392 "events", &xen_vcpu)) { 393 pr_err("Error request IRQ %d\n", xen_events_irq); 394 return -EINVAL; 395 } 396 397 if (!xen_kernel_unmapped_at_usr()) 398 xen_time_setup_guest(); 399 400 if (xen_initial_domain()) 401 pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier); 402 403 return cpuhp_setup_state(CPUHP_AP_ARM_XEN_STARTING, 404 "arm/xen:starting", xen_starting_cpu, 405 xen_dying_cpu); 406 } 407 early_initcall(xen_guest_init); 408 409 static int __init xen_pm_init(void) 410 { 411 if (!xen_domain()) 412 return -ENODEV; 413 414 pm_power_off = xen_power_off; 415 register_restart_handler(&xen_restart_nb); 416 if (!xen_initial_domain()) { 417 struct timespec64 ts; 418 xen_read_wallclock(&ts); 419 do_settimeofday64(&ts); 420 } 421 422 return 0; 423 } 424 late_initcall(xen_pm_init); 425 426 427 /* empty stubs */ 428 void xen_arch_pre_suspend(void) { } 429 void xen_arch_post_suspend(int suspend_cancelled) { } 430 void xen_timer_resume(void) { } 431 void xen_arch_resume(void) { } 432 void xen_arch_suspend(void) { } 433 434 435 /* In the hypercall.S file. */ 436 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op); 437 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op); 438 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version); 439 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io); 440 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op); 441 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op); 442 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op); 443 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op); 444 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op); 445 EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op_raw); 446 EXPORT_SYMBOL_GPL(HYPERVISOR_multicall); 447 EXPORT_SYMBOL_GPL(HYPERVISOR_vm_assist); 448 EXPORT_SYMBOL_GPL(HYPERVISOR_dm_op); 449 EXPORT_SYMBOL_GPL(privcmd_call); 450