1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2008, 2013 Citrix Systems, Inc. 5 * Copyright (c) 2012 Spectra Logic Corporation 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/param.h> 34 #include <sys/bus.h> 35 #include <sys/kernel.h> 36 #include <sys/malloc.h> 37 #include <sys/proc.h> 38 #include <sys/smp.h> 39 #include <sys/systm.h> 40 41 #include <vm/vm.h> 42 #include <vm/pmap.h> 43 #include <vm/vm_param.h> 44 45 #include <dev/pci/pcivar.h> 46 47 #include <machine/cpufunc.h> 48 #include <machine/cpu.h> 49 #include <machine/smp.h> 50 51 #include <x86/apicreg.h> 52 53 #include <xen/xen-os.h> 54 #include <xen/error.h> 55 #include <xen/features.h> 56 #include <xen/gnttab.h> 57 #include <xen/hypervisor.h> 58 #include <xen/hvm.h> 59 #include <xen/xen_intr.h> 60 61 #include <contrib/xen/arch-x86/cpuid.h> 62 #include <contrib/xen/hvm/params.h> 63 #include <contrib/xen/vcpu.h> 64 65 /*--------------------------- Forward Declarations ---------------------------*/ 66 static void xen_hvm_cpu_init(void); 67 68 /*-------------------------------- Global Data -------------------------------*/ 69 #ifdef SMP 70 struct cpu_ops xen_hvm_cpu_ops = { 71 .cpu_init = xen_hvm_cpu_init, 72 .cpu_resume = xen_hvm_cpu_init 73 }; 74 #endif 75 76 static MALLOC_DEFINE(M_XENHVM, "xen_hvm", "Xen HVM PV Support"); 77 78 /** 79 * If non-zero, the hypervisor has been configured to use a direct 80 * IDT event callback for interrupt injection. 81 */ 82 int xen_vector_callback_enabled; 83 84 /** 85 * Signal whether the vector injected for the event channel upcall requires to 86 * be EOI'ed on the local APIC. 87 */ 88 bool xen_evtchn_needs_ack; 89 90 /*------------------------------- Per-CPU Data -------------------------------*/ 91 DPCPU_DEFINE(struct vcpu_info, vcpu_local_info); 92 DPCPU_DEFINE(struct vcpu_info *, vcpu_info); 93 94 /*------------------------------ Sysctl tunables -----------------------------*/ 95 int xen_disable_pv_disks = 0; 96 int xen_disable_pv_nics = 0; 97 TUNABLE_INT("hw.xen.disable_pv_disks", &xen_disable_pv_disks); 98 TUNABLE_INT("hw.xen.disable_pv_nics", &xen_disable_pv_nics); 99 100 /*---------------------- XEN Hypervisor Probe and Setup ----------------------*/ 101 102 uint32_t xen_cpuid_base; 103 104 static uint32_t 105 xen_hvm_cpuid_base(void) 106 { 107 uint32_t base, regs[4]; 108 109 for (base = 0x40000000; base < 0x40010000; base += 0x100) { 110 do_cpuid(base, regs); 111 if (!memcmp("XenVMMXenVMM", ®s[1], 12) 112 && (regs[0] - base) >= 2) 113 return (base); 114 } 115 return (0); 116 } 117 118 static void 119 hypervisor_quirks(unsigned int major, unsigned int minor) 120 { 121 #ifdef SMP 122 if (((major < 4) || (major == 4 && minor <= 5)) && 123 msix_disable_migration == -1) { 124 /* 125 * Xen hypervisors prior to 4.6.0 do not properly 126 * handle updates to enabled MSI-X table entries, 127 * so disable MSI-X interrupt migration in that 128 * case. 129 */ 130 if (bootverbose) 131 printf( 132 "Disabling MSI-X interrupt migration due to Xen hypervisor bug.\n" 133 "Set machdep.msix_disable_migration=0 to forcefully enable it.\n"); 134 msix_disable_migration = 1; 135 } 136 #endif 137 } 138 139 static void 140 hypervisor_version(void) 141 { 142 uint32_t regs[4]; 143 int major, minor; 144 145 do_cpuid(xen_cpuid_base + 1, regs); 146 147 major = regs[0] >> 16; 148 minor = regs[0] & 0xffff; 149 printf("XEN: Hypervisor version %d.%d detected.\n", major, minor); 150 151 hypervisor_quirks(major, minor); 152 } 153 154 /* 155 * Allocate and fill in the hypcall page. 156 */ 157 int 158 xen_hvm_init_hypercall_stubs(enum xen_hvm_init_type init_type) 159 { 160 uint32_t regs[4]; 161 162 /* Legacy PVH will get here without the cpuid leaf being set. */ 163 if (xen_cpuid_base == 0) 164 xen_cpuid_base = xen_hvm_cpuid_base(); 165 if (xen_cpuid_base == 0) 166 return (ENXIO); 167 168 if (xen_domain() && init_type == XEN_HVM_INIT_LATE) { 169 /* 170 * If the domain type is already set we can assume that the 171 * hypercall page has been populated too, so just print the 172 * version (and apply any quirks) and exit. 173 */ 174 hypervisor_version(); 175 return 0; 176 } 177 178 if (init_type == XEN_HVM_INIT_LATE) 179 hypervisor_version(); 180 181 /* 182 * Find the hypercall pages. 183 */ 184 do_cpuid(xen_cpuid_base + 2, regs); 185 if (regs[0] != 1) 186 return (EINVAL); 187 188 wrmsr(regs[1], (init_type == XEN_HVM_INIT_EARLY) 189 ? (vm_paddr_t)((uintptr_t)&hypercall_page - KERNBASE) 190 : vtophys(&hypercall_page)); 191 192 return (0); 193 } 194 195 static void 196 xen_hvm_init_shared_info_page(void) 197 { 198 struct xen_add_to_physmap xatp; 199 200 if (xen_pv_domain()) { 201 /* 202 * Already setup in the PV case, shared_info is passed inside 203 * of the start_info struct at start of day. 204 */ 205 return; 206 } 207 208 if (HYPERVISOR_shared_info == NULL) { 209 HYPERVISOR_shared_info = malloc(PAGE_SIZE, M_XENHVM, M_NOWAIT); 210 if (HYPERVISOR_shared_info == NULL) 211 panic("Unable to allocate Xen shared info page"); 212 } 213 214 xatp.domid = DOMID_SELF; 215 xatp.idx = 0; 216 xatp.space = XENMAPSPACE_shared_info; 217 xatp.gpfn = vtophys(HYPERVISOR_shared_info) >> PAGE_SHIFT; 218 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) 219 panic("HYPERVISOR_memory_op failed"); 220 } 221 222 static int 223 set_percpu_callback(unsigned int vcpu) 224 { 225 struct xen_hvm_evtchn_upcall_vector vec; 226 int error; 227 228 vec.vcpu = vcpu; 229 vec.vector = IDT_EVTCHN; 230 error = HYPERVISOR_hvm_op(HVMOP_set_evtchn_upcall_vector, &vec); 231 232 return (error != 0 ? xen_translate_error(error) : 0); 233 } 234 235 /* 236 * Tell the hypervisor how to contact us for event channel callbacks. 237 */ 238 void 239 xen_hvm_set_callback(device_t dev) 240 { 241 struct xen_hvm_param xhp; 242 int irq; 243 244 if (xen_vector_callback_enabled) 245 return; 246 247 xhp.domid = DOMID_SELF; 248 xhp.index = HVM_PARAM_CALLBACK_IRQ; 249 if (xen_feature(XENFEAT_hvm_callback_vector) != 0) { 250 int error; 251 252 error = set_percpu_callback(0); 253 if (error == 0) { 254 xen_evtchn_needs_ack = true; 255 /* Trick toolstack to think we are enlightened */ 256 xhp.value = 1; 257 } else 258 xhp.value = HVM_CALLBACK_VECTOR(IDT_EVTCHN); 259 error = HYPERVISOR_hvm_op(HVMOP_set_param, &xhp); 260 if (error == 0) { 261 xen_vector_callback_enabled = 1; 262 return; 263 } else if (xen_evtchn_needs_ack) 264 panic("Unable to setup fake HVM param: %d", error); 265 266 printf("Xen HVM callback vector registration failed (%d). " 267 "Falling back to emulated device interrupt\n", error); 268 } 269 xen_vector_callback_enabled = 0; 270 if (dev == NULL) { 271 /* 272 * Called from early boot or resume. 273 * xenpci will invoke us again later. 274 */ 275 return; 276 } 277 278 irq = pci_get_irq(dev); 279 if (irq < 16) { 280 xhp.value = HVM_CALLBACK_GSI(irq); 281 } else { 282 u_int slot; 283 u_int pin; 284 285 slot = pci_get_slot(dev); 286 pin = pci_get_intpin(dev) - 1; 287 xhp.value = HVM_CALLBACK_PCI_INTX(slot, pin); 288 } 289 290 if (HYPERVISOR_hvm_op(HVMOP_set_param, &xhp) != 0) 291 panic("Can't set evtchn callback"); 292 } 293 294 #define XEN_MAGIC_IOPORT 0x10 295 enum { 296 XMI_MAGIC = 0x49d2, 297 XMI_UNPLUG_IDE_DISKS = 0x01, 298 XMI_UNPLUG_NICS = 0x02, 299 XMI_UNPLUG_IDE_EXCEPT_PRI_MASTER = 0x04 300 }; 301 302 static void 303 xen_hvm_disable_emulated_devices(void) 304 { 305 u_short disable_devs = 0; 306 307 if (xen_pv_domain()) { 308 /* 309 * No emulated devices in the PV case, so no need to unplug 310 * anything. 311 */ 312 if (xen_disable_pv_disks != 0 || xen_disable_pv_nics != 0) 313 printf("PV devices cannot be disabled in PV guests\n"); 314 return; 315 } 316 317 if (inw(XEN_MAGIC_IOPORT) != XMI_MAGIC) 318 return; 319 320 if (xen_disable_pv_disks == 0) { 321 if (bootverbose) 322 printf("XEN: disabling emulated disks\n"); 323 disable_devs |= XMI_UNPLUG_IDE_DISKS; 324 } 325 if (xen_disable_pv_nics == 0) { 326 if (bootverbose) 327 printf("XEN: disabling emulated nics\n"); 328 disable_devs |= XMI_UNPLUG_NICS; 329 } 330 331 if (disable_devs != 0) 332 outw(XEN_MAGIC_IOPORT, disable_devs); 333 } 334 335 static void 336 xen_hvm_init(enum xen_hvm_init_type init_type) 337 { 338 int error; 339 int i; 340 341 if (init_type == XEN_HVM_INIT_CANCELLED_SUSPEND) 342 return; 343 344 error = xen_hvm_init_hypercall_stubs(init_type); 345 346 switch (init_type) { 347 case XEN_HVM_INIT_LATE: 348 if (error != 0) 349 return; 350 351 /* 352 * If xen_domain_type is not set at this point 353 * it means we are inside a (PV)HVM guest, because 354 * for PVH the guest type is set much earlier 355 * (see hammer_time_xen). 356 */ 357 if (!xen_domain()) { 358 xen_domain_type = XEN_HVM_DOMAIN; 359 vm_guest = VM_GUEST_XEN; 360 } 361 362 setup_xen_features(); 363 #ifdef SMP 364 cpu_ops = xen_hvm_cpu_ops; 365 #endif 366 break; 367 case XEN_HVM_INIT_RESUME: 368 if (error != 0) 369 panic("Unable to init Xen hypercall stubs on resume"); 370 371 /* Clear stale vcpu_info. */ 372 CPU_FOREACH(i) 373 DPCPU_ID_SET(i, vcpu_info, NULL); 374 break; 375 default: 376 panic("Unsupported HVM initialization type"); 377 } 378 379 xen_vector_callback_enabled = 0; 380 xen_evtchn_needs_ack = false; 381 xen_hvm_set_callback(NULL); 382 383 /* 384 * On (PV)HVM domains we need to request the hypervisor to 385 * fill the shared info page, for PVH guest the shared_info page 386 * is passed inside the start_info struct and is already set, so this 387 * functions are no-ops. 388 */ 389 xen_hvm_init_shared_info_page(); 390 xen_hvm_disable_emulated_devices(); 391 } 392 393 void 394 xen_hvm_suspend(void) 395 { 396 } 397 398 void 399 xen_hvm_resume(bool suspend_cancelled) 400 { 401 402 xen_hvm_init(suspend_cancelled ? 403 XEN_HVM_INIT_CANCELLED_SUSPEND : XEN_HVM_INIT_RESUME); 404 405 /* Register vcpu_info area for CPU#0. */ 406 xen_hvm_cpu_init(); 407 } 408 409 static void 410 xen_hvm_sysinit(void *arg __unused) 411 { 412 xen_hvm_init(XEN_HVM_INIT_LATE); 413 } 414 SYSINIT(xen_hvm_init, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, xen_hvm_sysinit, NULL); 415 416 static void 417 xen_hvm_cpu_init(void) 418 { 419 struct vcpu_register_vcpu_info info; 420 struct vcpu_info *vcpu_info; 421 uint32_t regs[4]; 422 int cpu, rc; 423 424 if (!xen_domain()) 425 return; 426 427 if (DPCPU_GET(vcpu_info) != NULL) { 428 /* 429 * vcpu_info is already set. We're resuming 430 * from a failed migration and our pre-suspend 431 * configuration is still valid. 432 */ 433 return; 434 } 435 436 /* 437 * Set vCPU ID. If available fetch the ID from CPUID, if not just use 438 * the ACPI ID. 439 */ 440 KASSERT(xen_cpuid_base != 0, ("Invalid base Xen CPUID leaf")); 441 cpuid_count(xen_cpuid_base + 4, 0, regs); 442 KASSERT((regs[0] & XEN_HVM_CPUID_VCPU_ID_PRESENT) || 443 !xen_pv_domain(), 444 ("Xen PV domain without vcpu_id in cpuid")); 445 PCPU_SET(vcpu_id, (regs[0] & XEN_HVM_CPUID_VCPU_ID_PRESENT) ? 446 regs[1] : PCPU_GET(acpi_id)); 447 448 if (xen_evtchn_needs_ack && !IS_BSP()) { 449 /* 450 * Setup the per-vpcu event channel upcall vector. This is only 451 * required when using the new HVMOP_set_evtchn_upcall_vector 452 * hypercall, which allows using a different vector for each 453 * vCPU. Note that FreeBSD uses the same vector for all vCPUs 454 * because it's not dynamically allocated. 455 */ 456 rc = set_percpu_callback(PCPU_GET(vcpu_id)); 457 if (rc != 0) 458 panic("Event channel upcall vector setup failed: %d", 459 rc); 460 } 461 462 /* 463 * Set the vCPU info. 464 * 465 * NB: the vCPU info for vCPUs < 32 can be fetched from the shared info 466 * page, but in order to make sure the mapping code is correct always 467 * attempt to map the vCPU info at a custom place. 468 */ 469 vcpu_info = DPCPU_PTR(vcpu_local_info); 470 cpu = PCPU_GET(vcpu_id); 471 info.mfn = vtophys(vcpu_info) >> PAGE_SHIFT; 472 info.offset = vtophys(vcpu_info) - trunc_page(vtophys(vcpu_info)); 473 474 rc = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info); 475 if (rc != 0) 476 DPCPU_SET(vcpu_info, &HYPERVISOR_shared_info->vcpu_info[cpu]); 477 else 478 DPCPU_SET(vcpu_info, vcpu_info); 479 } 480 SYSINIT(xen_hvm_cpu_init, SI_SUB_INTR, SI_ORDER_FIRST, xen_hvm_cpu_init, NULL); 481 482 bool 483 xen_has_iommu_maps(void) 484 { 485 uint32_t regs[4]; 486 487 KASSERT(xen_cpuid_base != 0, ("Invalid base Xen CPUID leaf")); 488 cpuid_count(xen_cpuid_base + 4, 0, regs); 489 490 return (regs[0] & XEN_HVM_CPUID_IOMMU_MAPPINGS); 491 } 492