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 #include <linux/virtio_anchor.h> 38 39 #include <linux/mm.h> 40 41 static struct start_info _xen_start_info; 42 struct start_info *xen_start_info = &_xen_start_info; 43 EXPORT_SYMBOL(xen_start_info); 44 45 enum xen_domain_type xen_domain_type = XEN_NATIVE; 46 EXPORT_SYMBOL(xen_domain_type); 47 48 struct shared_info xen_dummy_shared_info; 49 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; 50 51 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); 52 static struct vcpu_info __percpu *xen_vcpu_info; 53 54 /* Linux <-> Xen vCPU id mapping */ 55 DEFINE_PER_CPU(uint32_t, xen_vcpu_id); 56 EXPORT_PER_CPU_SYMBOL(xen_vcpu_id); 57 58 /* These are unused until we support booting "pre-ballooned" */ 59 unsigned long xen_released_pages; 60 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; 61 62 static __read_mostly unsigned int xen_events_irq; 63 static __read_mostly phys_addr_t xen_grant_frames; 64 65 #define GRANT_TABLE_INDEX 0 66 #define EXT_REGION_INDEX 1 67 68 uint32_t xen_start_flags; 69 EXPORT_SYMBOL(xen_start_flags); 70 71 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, 72 int nr, struct page **pages) 73 { 74 return xen_xlate_unmap_gfn_range(vma, nr, pages); 75 } 76 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); 77 78 static void xen_read_wallclock(struct timespec64 *ts) 79 { 80 u32 version; 81 struct timespec64 now, ts_monotonic; 82 struct shared_info *s = HYPERVISOR_shared_info; 83 struct pvclock_wall_clock *wall_clock = &(s->wc); 84 85 /* get wallclock at system boot */ 86 do { 87 version = wall_clock->version; 88 rmb(); /* fetch version before time */ 89 now.tv_sec = ((uint64_t)wall_clock->sec_hi << 32) | wall_clock->sec; 90 now.tv_nsec = wall_clock->nsec; 91 rmb(); /* fetch time before checking version */ 92 } while ((wall_clock->version & 1) || (version != wall_clock->version)); 93 94 /* time since system boot */ 95 ktime_get_ts64(&ts_monotonic); 96 *ts = timespec64_add(now, ts_monotonic); 97 } 98 99 static int xen_pvclock_gtod_notify(struct notifier_block *nb, 100 unsigned long was_set, void *priv) 101 { 102 /* Protected by the calling core code serialization */ 103 static struct timespec64 next_sync; 104 105 struct xen_platform_op op; 106 struct timespec64 now, system_time; 107 struct timekeeper *tk = priv; 108 109 now.tv_sec = tk->xtime_sec; 110 now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); 111 system_time = timespec64_add(now, tk->wall_to_monotonic); 112 113 /* 114 * We only take the expensive HV call when the clock was set 115 * or when the 11 minutes RTC synchronization time elapsed. 116 */ 117 if (!was_set && timespec64_compare(&now, &next_sync) < 0) 118 return NOTIFY_OK; 119 120 op.cmd = XENPF_settime64; 121 op.u.settime64.mbz = 0; 122 op.u.settime64.secs = now.tv_sec; 123 op.u.settime64.nsecs = now.tv_nsec; 124 op.u.settime64.system_time = timespec64_to_ns(&system_time); 125 (void)HYPERVISOR_platform_op(&op); 126 127 /* 128 * Move the next drift compensation time 11 minutes 129 * ahead. That's emulating the sync_cmos_clock() update for 130 * the hardware RTC. 131 */ 132 next_sync = now; 133 next_sync.tv_sec += 11 * 60; 134 135 return NOTIFY_OK; 136 } 137 138 static struct notifier_block xen_pvclock_gtod_notifier = { 139 .notifier_call = xen_pvclock_gtod_notify, 140 }; 141 142 static int xen_starting_cpu(unsigned int cpu) 143 { 144 struct vcpu_register_vcpu_info info; 145 struct vcpu_info *vcpup; 146 int err; 147 148 /* 149 * VCPUOP_register_vcpu_info cannot be called twice for the same 150 * vcpu, so if vcpu_info is already registered, just get out. This 151 * can happen with cpu-hotplug. 152 */ 153 if (per_cpu(xen_vcpu, cpu) != NULL) 154 goto after_register_vcpu_info; 155 156 pr_info("Xen: initializing cpu%d\n", cpu); 157 vcpup = per_cpu_ptr(xen_vcpu_info, cpu); 158 159 info.mfn = percpu_to_gfn(vcpup); 160 info.offset = xen_offset_in_page(vcpup); 161 162 err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, xen_vcpu_nr(cpu), 163 &info); 164 BUG_ON(err); 165 per_cpu(xen_vcpu, cpu) = vcpup; 166 167 if (!xen_kernel_unmapped_at_usr()) 168 xen_setup_runstate_info(cpu); 169 170 after_register_vcpu_info: 171 enable_percpu_irq(xen_events_irq, 0); 172 return 0; 173 } 174 175 static int xen_dying_cpu(unsigned int cpu) 176 { 177 disable_percpu_irq(xen_events_irq); 178 return 0; 179 } 180 181 void xen_reboot(int reason) 182 { 183 struct sched_shutdown r = { .reason = reason }; 184 int rc; 185 186 rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r); 187 BUG_ON(rc); 188 } 189 190 static int xen_restart(struct notifier_block *nb, unsigned long action, 191 void *data) 192 { 193 xen_reboot(SHUTDOWN_reboot); 194 195 return NOTIFY_DONE; 196 } 197 198 static struct notifier_block xen_restart_nb = { 199 .notifier_call = xen_restart, 200 .priority = 192, 201 }; 202 203 static void xen_power_off(void) 204 { 205 xen_reboot(SHUTDOWN_poweroff); 206 } 207 208 static irqreturn_t xen_arm_callback(int irq, void *arg) 209 { 210 xen_hvm_evtchn_do_upcall(); 211 return IRQ_HANDLED; 212 } 213 214 static __initdata struct { 215 const char *compat; 216 const char *prefix; 217 const char *version; 218 bool found; 219 } hyper_node = {"xen,xen", "xen,xen-", NULL, false}; 220 221 static int __init fdt_find_hyper_node(unsigned long node, const char *uname, 222 int depth, void *data) 223 { 224 const void *s = NULL; 225 int len; 226 227 if (depth != 1 || strcmp(uname, "hypervisor") != 0) 228 return 0; 229 230 if (of_flat_dt_is_compatible(node, hyper_node.compat)) 231 hyper_node.found = true; 232 233 s = of_get_flat_dt_prop(node, "compatible", &len); 234 if (strlen(hyper_node.prefix) + 3 < len && 235 !strncmp(hyper_node.prefix, s, strlen(hyper_node.prefix))) 236 hyper_node.version = s + strlen(hyper_node.prefix); 237 238 /* 239 * Check if Xen supports EFI by checking whether there is the 240 * "/hypervisor/uefi" node in DT. If so, runtime services are available 241 * through proxy functions (e.g. in case of Xen dom0 EFI implementation 242 * they call special hypercall which executes relevant EFI functions) 243 * and that is why they are always enabled. 244 */ 245 if (IS_ENABLED(CONFIG_XEN_EFI)) { 246 if ((of_get_flat_dt_subnode_by_name(node, "uefi") > 0) && 247 !efi_runtime_disabled()) 248 set_bit(EFI_RUNTIME_SERVICES, &efi.flags); 249 } 250 251 return 0; 252 } 253 254 /* 255 * see Documentation/devicetree/bindings/arm/xen.txt for the 256 * documentation of the Xen Device Tree format. 257 */ 258 void __init xen_early_init(void) 259 { 260 of_scan_flat_dt(fdt_find_hyper_node, NULL); 261 if (!hyper_node.found) { 262 pr_debug("No Xen support\n"); 263 return; 264 } 265 266 if (hyper_node.version == NULL) { 267 pr_debug("Xen version not found\n"); 268 return; 269 } 270 271 pr_info("Xen %s support found\n", hyper_node.version); 272 273 xen_domain_type = XEN_HVM_DOMAIN; 274 275 xen_setup_features(); 276 277 if (xen_feature(XENFEAT_dom0)) 278 xen_start_flags |= SIF_INITDOMAIN|SIF_PRIVILEGED; 279 280 if (!console_set_on_cmdline && !xen_initial_domain()) 281 add_preferred_console("hvc", 0, NULL); 282 } 283 284 static void __init xen_acpi_guest_init(void) 285 { 286 #ifdef CONFIG_ACPI 287 struct xen_hvm_param a; 288 int interrupt, trigger, polarity; 289 290 a.domid = DOMID_SELF; 291 a.index = HVM_PARAM_CALLBACK_IRQ; 292 293 if (HYPERVISOR_hvm_op(HVMOP_get_param, &a) 294 || (a.value >> 56) != HVM_PARAM_CALLBACK_TYPE_PPI) { 295 xen_events_irq = 0; 296 return; 297 } 298 299 interrupt = a.value & 0xff; 300 trigger = ((a.value >> 8) & 0x1) ? ACPI_EDGE_SENSITIVE 301 : ACPI_LEVEL_SENSITIVE; 302 polarity = ((a.value >> 8) & 0x2) ? ACPI_ACTIVE_LOW 303 : ACPI_ACTIVE_HIGH; 304 xen_events_irq = acpi_register_gsi(NULL, interrupt, trigger, polarity); 305 #endif 306 } 307 308 #ifdef CONFIG_XEN_UNPOPULATED_ALLOC 309 /* 310 * A type-less specific Xen resource which contains extended regions 311 * (unused regions of guest physical address space provided by the hypervisor). 312 */ 313 static struct resource xen_resource = { 314 .name = "Xen unused space", 315 }; 316 317 int __init arch_xen_unpopulated_init(struct resource **res) 318 { 319 struct device_node *np; 320 struct resource *regs, *tmp_res; 321 uint64_t min_gpaddr = -1, max_gpaddr = 0; 322 unsigned int i, nr_reg = 0; 323 int rc; 324 325 if (!xen_domain()) 326 return -ENODEV; 327 328 if (!acpi_disabled) 329 return -ENODEV; 330 331 np = of_find_compatible_node(NULL, NULL, "xen,xen"); 332 if (WARN_ON(!np)) 333 return -ENODEV; 334 335 /* Skip region 0 which is reserved for grant table space */ 336 while (of_get_address(np, nr_reg + EXT_REGION_INDEX, NULL, NULL)) 337 nr_reg++; 338 339 if (!nr_reg) { 340 pr_err("No extended regions are found\n"); 341 of_node_put(np); 342 return -EINVAL; 343 } 344 345 regs = kcalloc(nr_reg, sizeof(*regs), GFP_KERNEL); 346 if (!regs) { 347 of_node_put(np); 348 return -ENOMEM; 349 } 350 351 /* 352 * Create resource from extended regions provided by the hypervisor to be 353 * used as unused address space for Xen scratch pages. 354 */ 355 for (i = 0; i < nr_reg; i++) { 356 rc = of_address_to_resource(np, i + EXT_REGION_INDEX, ®s[i]); 357 if (rc) 358 goto err; 359 360 if (max_gpaddr < regs[i].end) 361 max_gpaddr = regs[i].end; 362 if (min_gpaddr > regs[i].start) 363 min_gpaddr = regs[i].start; 364 } 365 366 xen_resource.start = min_gpaddr; 367 xen_resource.end = max_gpaddr; 368 369 /* 370 * Mark holes between extended regions as unavailable. The rest of that 371 * address space will be available for the allocation. 372 */ 373 for (i = 1; i < nr_reg; i++) { 374 resource_size_t start, end; 375 376 /* There is an overlap between regions */ 377 if (regs[i - 1].end + 1 > regs[i].start) { 378 rc = -EINVAL; 379 goto err; 380 } 381 382 /* There is no hole between regions */ 383 if (regs[i - 1].end + 1 == regs[i].start) 384 continue; 385 386 start = regs[i - 1].end + 1; 387 end = regs[i].start - 1; 388 389 tmp_res = kzalloc(sizeof(*tmp_res), GFP_KERNEL); 390 if (!tmp_res) { 391 rc = -ENOMEM; 392 goto err; 393 } 394 395 tmp_res->name = "Unavailable space"; 396 tmp_res->start = start; 397 tmp_res->end = end; 398 399 rc = insert_resource(&xen_resource, tmp_res); 400 if (rc) { 401 pr_err("Cannot insert resource %pR (%d)\n", tmp_res, rc); 402 kfree(tmp_res); 403 goto err; 404 } 405 } 406 407 *res = &xen_resource; 408 409 err: 410 of_node_put(np); 411 kfree(regs); 412 return rc; 413 } 414 #endif 415 416 static void __init xen_dt_guest_init(void) 417 { 418 struct device_node *xen_node; 419 struct resource res; 420 421 xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); 422 if (!xen_node) { 423 pr_err("Xen support was detected before, but it has disappeared\n"); 424 return; 425 } 426 427 xen_events_irq = irq_of_parse_and_map(xen_node, 0); 428 429 if (of_address_to_resource(xen_node, GRANT_TABLE_INDEX, &res)) { 430 pr_err("Xen grant table region is not found\n"); 431 of_node_put(xen_node); 432 return; 433 } 434 of_node_put(xen_node); 435 xen_grant_frames = res.start; 436 } 437 438 static int __init xen_guest_init(void) 439 { 440 struct xen_add_to_physmap xatp; 441 struct shared_info *shared_info_page = NULL; 442 int rc, cpu; 443 444 if (!xen_domain()) 445 return 0; 446 447 if (IS_ENABLED(CONFIG_XEN_VIRTIO)) 448 virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc); 449 450 if (!acpi_disabled) 451 xen_acpi_guest_init(); 452 else 453 xen_dt_guest_init(); 454 455 if (!xen_events_irq) { 456 pr_err("Xen event channel interrupt not found\n"); 457 return -ENODEV; 458 } 459 460 /* 461 * The fdt parsing codes have set EFI_RUNTIME_SERVICES if Xen EFI 462 * parameters are found. Force enable runtime services. 463 */ 464 if (efi_enabled(EFI_RUNTIME_SERVICES)) 465 xen_efi_runtime_setup(); 466 467 shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL); 468 469 if (!shared_info_page) { 470 pr_err("not enough memory\n"); 471 return -ENOMEM; 472 } 473 xatp.domid = DOMID_SELF; 474 xatp.idx = 0; 475 xatp.space = XENMAPSPACE_shared_info; 476 xatp.gpfn = virt_to_gfn(shared_info_page); 477 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) 478 BUG(); 479 480 HYPERVISOR_shared_info = (struct shared_info *)shared_info_page; 481 482 /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info 483 * page, we use it in the event channel upcall and in some pvclock 484 * related functions. 485 * The shared info contains exactly 1 CPU (the boot CPU). The guest 486 * is required to use VCPUOP_register_vcpu_info to place vcpu info 487 * for secondary CPUs as they are brought up. 488 * For uniformity we use VCPUOP_register_vcpu_info even on cpu0. 489 */ 490 xen_vcpu_info = alloc_percpu(struct vcpu_info); 491 if (xen_vcpu_info == NULL) 492 return -ENOMEM; 493 494 /* Direct vCPU id mapping for ARM guests. */ 495 for_each_possible_cpu(cpu) 496 per_cpu(xen_vcpu_id, cpu) = cpu; 497 498 if (!xen_grant_frames) { 499 xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); 500 rc = xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, 501 &xen_auto_xlat_grant_frames.vaddr, 502 xen_auto_xlat_grant_frames.count); 503 } else 504 rc = gnttab_setup_auto_xlat_frames(xen_grant_frames); 505 if (rc) { 506 free_percpu(xen_vcpu_info); 507 return rc; 508 } 509 gnttab_init(); 510 511 /* 512 * Making sure board specific code will not set up ops for 513 * cpu idle and cpu freq. 514 */ 515 disable_cpuidle(); 516 disable_cpufreq(); 517 518 xen_init_IRQ(); 519 520 if (request_percpu_irq(xen_events_irq, xen_arm_callback, 521 "events", &xen_vcpu)) { 522 pr_err("Error request IRQ %d\n", xen_events_irq); 523 return -EINVAL; 524 } 525 526 if (!xen_kernel_unmapped_at_usr()) 527 xen_time_setup_guest(); 528 529 if (xen_initial_domain()) 530 pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier); 531 532 return cpuhp_setup_state(CPUHP_AP_ARM_XEN_STARTING, 533 "arm/xen:starting", xen_starting_cpu, 534 xen_dying_cpu); 535 } 536 early_initcall(xen_guest_init); 537 538 static int __init xen_pm_init(void) 539 { 540 if (!xen_domain()) 541 return -ENODEV; 542 543 pm_power_off = xen_power_off; 544 register_restart_handler(&xen_restart_nb); 545 if (!xen_initial_domain()) { 546 struct timespec64 ts; 547 xen_read_wallclock(&ts); 548 do_settimeofday64(&ts); 549 } 550 551 return 0; 552 } 553 late_initcall(xen_pm_init); 554 555 556 /* empty stubs */ 557 void xen_arch_pre_suspend(void) { } 558 void xen_arch_post_suspend(int suspend_cancelled) { } 559 void xen_timer_resume(void) { } 560 void xen_arch_resume(void) { } 561 void xen_arch_suspend(void) { } 562 563 564 /* In the hypercall.S file. */ 565 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op); 566 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op); 567 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version); 568 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io); 569 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op); 570 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op); 571 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op); 572 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op); 573 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op); 574 EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op_raw); 575 EXPORT_SYMBOL_GPL(HYPERVISOR_multicall); 576 EXPORT_SYMBOL_GPL(HYPERVISOR_vm_assist); 577 EXPORT_SYMBOL_GPL(HYPERVISOR_dm_op); 578 EXPORT_SYMBOL_GPL(privcmd_call); 579