1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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_DECLARE(struct vcpu_info *, vcpu_info); 92 93 /*------------------------------ Sysctl tunables -----------------------------*/ 94 int xen_disable_pv_disks = 0; 95 int xen_disable_pv_nics = 0; 96 TUNABLE_INT("hw.xen.disable_pv_disks", &xen_disable_pv_disks); 97 TUNABLE_INT("hw.xen.disable_pv_nics", &xen_disable_pv_nics); 98 99 /*---------------------- XEN Hypervisor Probe and Setup ----------------------*/ 100 101 uint32_t xen_cpuid_base; 102 103 static uint32_t 104 xen_hvm_cpuid_base(void) 105 { 106 uint32_t base, regs[4]; 107 108 for (base = 0x40000000; base < 0x40010000; base += 0x100) { 109 do_cpuid(base, regs); 110 if (!memcmp("XenVMMXenVMM", ®s[1], 12) 111 && (regs[0] - base) >= 2) 112 return (base); 113 } 114 return (0); 115 } 116 117 static void 118 hypervisor_quirks(unsigned int major, unsigned int minor) 119 { 120 #ifdef SMP 121 if (((major < 4) || (major == 4 && minor <= 5)) && 122 msix_disable_migration == -1) { 123 /* 124 * Xen hypervisors prior to 4.6.0 do not properly 125 * handle updates to enabled MSI-X table entries, 126 * so disable MSI-X interrupt migration in that 127 * case. 128 */ 129 if (bootverbose) 130 printf( 131 "Disabling MSI-X interrupt migration due to Xen hypervisor bug.\n" 132 "Set machdep.msix_disable_migration=0 to forcefully enable it.\n"); 133 msix_disable_migration = 1; 134 } 135 #endif 136 } 137 138 static void 139 hypervisor_version(void) 140 { 141 uint32_t regs[4]; 142 int major, minor; 143 144 do_cpuid(xen_cpuid_base + 1, regs); 145 146 major = regs[0] >> 16; 147 minor = regs[0] & 0xffff; 148 printf("XEN: Hypervisor version %d.%d detected.\n", major, minor); 149 150 hypervisor_quirks(major, minor); 151 } 152 153 /* 154 * Allocate and fill in the hypcall page. 155 */ 156 int 157 xen_hvm_init_hypercall_stubs(enum xen_hvm_init_type init_type) 158 { 159 uint32_t regs[4]; 160 161 /* Legacy PVH will get here without the cpuid leaf being set. */ 162 if (xen_cpuid_base == 0) 163 xen_cpuid_base = xen_hvm_cpuid_base(); 164 if (xen_cpuid_base == 0) 165 return (ENXIO); 166 167 if (xen_domain() && init_type == XEN_HVM_INIT_LATE) { 168 /* 169 * If the domain type is already set we can assume that the 170 * hypercall page has been populated too, so just print the 171 * version (and apply any quirks) and exit. 172 */ 173 hypervisor_version(); 174 return 0; 175 } 176 177 if (init_type == XEN_HVM_INIT_LATE) 178 hypervisor_version(); 179 180 /* 181 * Find the hypercall pages. 182 */ 183 do_cpuid(xen_cpuid_base + 2, regs); 184 if (regs[0] != 1) 185 return (EINVAL); 186 187 wrmsr(regs[1], (init_type == XEN_HVM_INIT_EARLY) 188 ? (vm_paddr_t)((uintptr_t)&hypercall_page - KERNBASE) 189 : vtophys(&hypercall_page)); 190 191 return (0); 192 } 193 194 static void 195 xen_hvm_init_shared_info_page(void) 196 { 197 struct xen_add_to_physmap xatp; 198 199 if (xen_pv_domain()) { 200 /* 201 * Already setup in the PV case, shared_info is passed inside 202 * of the start_info struct at start of day. 203 */ 204 return; 205 } 206 207 if (HYPERVISOR_shared_info == NULL) { 208 HYPERVISOR_shared_info = malloc(PAGE_SIZE, M_XENHVM, M_NOWAIT); 209 if (HYPERVISOR_shared_info == NULL) 210 panic("Unable to allocate Xen shared info page"); 211 } 212 213 xatp.domid = DOMID_SELF; 214 xatp.idx = 0; 215 xatp.space = XENMAPSPACE_shared_info; 216 xatp.gpfn = vtophys(HYPERVISOR_shared_info) >> PAGE_SHIFT; 217 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) 218 panic("HYPERVISOR_memory_op failed"); 219 } 220 221 static int 222 set_percpu_callback(unsigned int vcpu) 223 { 224 struct xen_hvm_evtchn_upcall_vector vec; 225 int error; 226 227 vec.vcpu = vcpu; 228 vec.vector = IDT_EVTCHN; 229 error = HYPERVISOR_hvm_op(HVMOP_set_evtchn_upcall_vector, &vec); 230 231 return (error != 0 ? xen_translate_error(error) : 0); 232 } 233 234 /* 235 * Tell the hypervisor how to contact us for event channel callbacks. 236 */ 237 void 238 xen_hvm_set_callback(device_t dev) 239 { 240 struct xen_hvm_param xhp; 241 int irq; 242 243 if (xen_vector_callback_enabled) 244 return; 245 246 xhp.domid = DOMID_SELF; 247 xhp.index = HVM_PARAM_CALLBACK_IRQ; 248 if (xen_feature(XENFEAT_hvm_callback_vector) != 0) { 249 int error; 250 251 error = set_percpu_callback(0); 252 if (error == 0) { 253 xen_evtchn_needs_ack = true; 254 /* Trick toolstack to think we are enlightened */ 255 xhp.value = 1; 256 } else 257 xhp.value = HVM_CALLBACK_VECTOR(IDT_EVTCHN); 258 error = HYPERVISOR_hvm_op(HVMOP_set_param, &xhp); 259 if (error == 0) { 260 xen_vector_callback_enabled = 1; 261 return; 262 } else if (xen_evtchn_needs_ack) 263 panic("Unable to setup fake HVM param: %d", error); 264 265 printf("Xen HVM callback vector registration failed (%d). " 266 "Falling back to emulated device interrupt\n", error); 267 } 268 xen_vector_callback_enabled = 0; 269 if (dev == NULL) { 270 /* 271 * Called from early boot or resume. 272 * xenpci will invoke us again later. 273 */ 274 return; 275 } 276 277 irq = pci_get_irq(dev); 278 if (irq < 16) { 279 xhp.value = HVM_CALLBACK_GSI(irq); 280 } else { 281 u_int slot; 282 u_int pin; 283 284 slot = pci_get_slot(dev); 285 pin = pci_get_intpin(dev) - 1; 286 xhp.value = HVM_CALLBACK_PCI_INTX(slot, pin); 287 } 288 289 if (HYPERVISOR_hvm_op(HVMOP_set_param, &xhp) != 0) 290 panic("Can't set evtchn callback"); 291 } 292 293 #define XEN_MAGIC_IOPORT 0x10 294 enum { 295 XMI_MAGIC = 0x49d2, 296 XMI_UNPLUG_IDE_DISKS = 0x01, 297 XMI_UNPLUG_NICS = 0x02, 298 XMI_UNPLUG_IDE_EXCEPT_PRI_MASTER = 0x04 299 }; 300 301 static void 302 xen_hvm_disable_emulated_devices(void) 303 { 304 u_short disable_devs = 0; 305 306 if (xen_pv_domain()) { 307 /* 308 * No emulated devices in the PV case, so no need to unplug 309 * anything. 310 */ 311 if (xen_disable_pv_disks != 0 || xen_disable_pv_nics != 0) 312 printf("PV devices cannot be disabled in PV guests\n"); 313 return; 314 } 315 316 if (inw(XEN_MAGIC_IOPORT) != XMI_MAGIC) 317 return; 318 319 if (xen_disable_pv_disks == 0) { 320 if (bootverbose) 321 printf("XEN: disabling emulated disks\n"); 322 disable_devs |= XMI_UNPLUG_IDE_DISKS; 323 } 324 if (xen_disable_pv_nics == 0) { 325 if (bootverbose) 326 printf("XEN: disabling emulated nics\n"); 327 disable_devs |= XMI_UNPLUG_NICS; 328 } 329 330 if (disable_devs != 0) 331 outw(XEN_MAGIC_IOPORT, disable_devs); 332 } 333 334 static void 335 xen_hvm_init(enum xen_hvm_init_type init_type) 336 { 337 int error; 338 int i; 339 340 if (init_type == XEN_HVM_INIT_CANCELLED_SUSPEND) 341 return; 342 343 error = xen_hvm_init_hypercall_stubs(init_type); 344 345 switch (init_type) { 346 case XEN_HVM_INIT_LATE: 347 if (error != 0) 348 return; 349 350 /* 351 * If xen_domain_type is not set at this point 352 * it means we are inside a (PV)HVM guest, because 353 * for PVH the guest type is set much earlier 354 * (see hammer_time_xen). 355 */ 356 if (!xen_domain()) { 357 xen_domain_type = XEN_HVM_DOMAIN; 358 vm_guest = VM_GUEST_XEN; 359 } 360 361 setup_xen_features(); 362 #ifdef SMP 363 cpu_ops = xen_hvm_cpu_ops; 364 #endif 365 break; 366 case XEN_HVM_INIT_RESUME: 367 if (error != 0) 368 panic("Unable to init Xen hypercall stubs on resume"); 369 370 /* Clear stale vcpu_info. */ 371 CPU_FOREACH(i) 372 DPCPU_ID_SET(i, vcpu_info, NULL); 373 break; 374 default: 375 panic("Unsupported HVM initialization type"); 376 } 377 378 xen_vector_callback_enabled = 0; 379 xen_evtchn_needs_ack = false; 380 xen_hvm_set_callback(NULL); 381 382 /* 383 * On (PV)HVM domains we need to request the hypervisor to 384 * fill the shared info page, for PVH guest the shared_info page 385 * is passed inside the start_info struct and is already set, so this 386 * functions are no-ops. 387 */ 388 xen_hvm_init_shared_info_page(); 389 xen_hvm_disable_emulated_devices(); 390 } 391 392 void 393 xen_hvm_suspend(void) 394 { 395 } 396 397 void 398 xen_hvm_resume(bool suspend_cancelled) 399 { 400 401 xen_hvm_init(suspend_cancelled ? 402 XEN_HVM_INIT_CANCELLED_SUSPEND : XEN_HVM_INIT_RESUME); 403 404 /* Register vcpu_info area for CPU#0. */ 405 xen_hvm_cpu_init(); 406 } 407 408 static void 409 xen_hvm_sysinit(void *arg __unused) 410 { 411 xen_hvm_init(XEN_HVM_INIT_LATE); 412 } 413 SYSINIT(xen_hvm_init, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, xen_hvm_sysinit, NULL); 414 415 static void 416 xen_hvm_cpu_init(void) 417 { 418 uint32_t regs[4]; 419 int rc; 420 421 if (!xen_domain()) 422 return; 423 424 if (DPCPU_GET(vcpu_info) != NULL) { 425 /* 426 * vcpu_info is already set. We're resuming 427 * from a failed migration and our pre-suspend 428 * configuration is still valid. 429 */ 430 return; 431 } 432 433 /* 434 * Set vCPU ID. If available fetch the ID from CPUID, if not just use 435 * the ACPI ID. 436 */ 437 KASSERT(xen_cpuid_base != 0, ("Invalid base Xen CPUID leaf")); 438 cpuid_count(xen_cpuid_base + 4, 0, regs); 439 KASSERT((regs[0] & XEN_HVM_CPUID_VCPU_ID_PRESENT) || 440 !xen_pv_domain(), 441 ("Xen PV domain without vcpu_id in cpuid")); 442 PCPU_SET(vcpu_id, (regs[0] & XEN_HVM_CPUID_VCPU_ID_PRESENT) ? 443 regs[1] : PCPU_GET(acpi_id)); 444 445 if (xen_evtchn_needs_ack && !IS_BSP()) { 446 /* 447 * Setup the per-vpcu event channel upcall vector. This is only 448 * required when using the new HVMOP_set_evtchn_upcall_vector 449 * hypercall, which allows using a different vector for each 450 * vCPU. Note that FreeBSD uses the same vector for all vCPUs 451 * because it's not dynamically allocated. 452 */ 453 rc = set_percpu_callback(PCPU_GET(vcpu_id)); 454 if (rc != 0) 455 panic("Event channel upcall vector setup failed: %d", 456 rc); 457 } 458 459 xen_setup_vcpu_info(); 460 } 461 SYSINIT(xen_hvm_cpu_init, SI_SUB_INTR, SI_ORDER_FIRST, xen_hvm_cpu_init, NULL); 462 463 bool 464 xen_has_iommu_maps(void) 465 { 466 uint32_t regs[4]; 467 468 KASSERT(xen_cpuid_base != 0, ("Invalid base Xen CPUID leaf")); 469 cpuid_count(xen_cpuid_base + 4, 0, regs); 470 471 return (regs[0] & XEN_HVM_CPUID_IOMMU_MAPPINGS); 472 } 473