sys/dev/hyperv/vmbus/hyperv.c

   1 /*-
   2  * Copyright (c) 2009-2012,2016-2017 Microsoft Corp.
   3  * Copyright (c) 2012 NetApp Inc.
   4  * Copyright (c) 2012 Citrix Inc.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice unmodified, this list of conditions, and the following
  12  *    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 ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /**
  30  * Implements low-level interactions with Hyper-V/Azure
  31  */
  32 #include <sys/cdefs.h>
  33 __FBSDID("$FreeBSD$");
  34
  35 #include <sys/param.h>
  36 #include <sys/kernel.h>
  37 #include <sys/malloc.h>
  38 #include <sys/systm.h>
  39 #include <sys/timetc.h>
  40
  41 #include <vm/vm.h>
  42 #include <vm/vm_extern.h>
  43 #include <vm/vm_kern.h>
  44 #include <vm/pmap.h>
  45
  46 #include <dev/hyperv/include/hyperv.h>
  47 #include <dev/hyperv/include/hyperv_busdma.h>
  48 #include <dev/hyperv/vmbus/hyperv_machdep.h>
  49 #include <dev/hyperv/vmbus/hyperv_reg.h>
  50 #include <dev/hyperv/vmbus/hyperv_var.h>
  51
  52 #define HYPERV_FREEBSD_BUILD            0ULL
  53 #define HYPERV_FREEBSD_VERSION          ((uint64_t)__FreeBSD_version)
  54 #define HYPERV_FREEBSD_OSID             0ULL
  55
  56 #define MSR_HV_GUESTID_BUILD_FREEBSD    \
  57         (HYPERV_FREEBSD_BUILD & MSR_HV_GUESTID_BUILD_MASK)
  58 #define MSR_HV_GUESTID_VERSION_FREEBSD  \
  59         ((HYPERV_FREEBSD_VERSION << MSR_HV_GUESTID_VERSION_SHIFT) & \
  60          MSR_HV_GUESTID_VERSION_MASK)
  61 #define MSR_HV_GUESTID_OSID_FREEBSD     \
  62         ((HYPERV_FREEBSD_OSID << MSR_HV_GUESTID_OSID_SHIFT) & \
  63          MSR_HV_GUESTID_OSID_MASK)
  64
  65 #define MSR_HV_GUESTID_FREEBSD          \
  66         (MSR_HV_GUESTID_BUILD_FREEBSD | \
  67          MSR_HV_GUESTID_VERSION_FREEBSD | \
  68          MSR_HV_GUESTID_OSID_FREEBSD |  \
  69          MSR_HV_GUESTID_OSTYPE_FREEBSD)
  70
  71 struct hypercall_ctx {
  72         void                    *hc_addr;
  73         vm_paddr_t              hc_paddr;
  74 };
  75
  76 static u_int                    hyperv_get_timecount(struct timecounter *);
  77 static bool                     hyperv_identify(void);
  78 static void                     hypercall_memfree(void);
  79
  80 u_int                           hyperv_ver_major;
  81
  82 u_int                           hyperv_features;
  83 u_int                           hyperv_recommends;
  84
  85 static u_int                    hyperv_pm_features;
  86 static u_int                    hyperv_features3;
  87
  88 hyperv_tc64_t                   hyperv_tc64;
  89
  90 static struct timecounter       hyperv_timecounter = {
  91         .tc_get_timecount       = hyperv_get_timecount,
  92         .tc_poll_pps            = NULL,
  93         .tc_counter_mask        = 0xffffffff,
  94         .tc_frequency           = HYPERV_TIMER_FREQ,
  95         .tc_name                = "Hyper-V",
  96         .tc_quality             = 2000,
  97         .tc_flags               = 0,
  98         .tc_priv                = NULL
  99 };
 100
 101 static struct hypercall_ctx     hypercall_context;
 102
 103 static u_int
 104 hyperv_get_timecount(struct timecounter *tc __unused)
 105 {
 106         return rdmsr(MSR_HV_TIME_REF_COUNT);
 107 }
 108
 109 static uint64_t
 110 hyperv_tc64_rdmsr(void)
 111 {
 112
 113         return (rdmsr(MSR_HV_TIME_REF_COUNT));
 114 }
 115
 116 uint64_t
 117 hypercall_post_message(bus_addr_t msg_paddr)
 118 {
 119         return hypercall_md(hypercall_context.hc_addr,
 120             HYPERCALL_POST_MESSAGE, msg_paddr, 0);
 121 }
 122
 123 uint64_t
 124 hypercall_signal_event(bus_addr_t monprm_paddr)
 125 {
 126         return hypercall_md(hypercall_context.hc_addr,
 127             HYPERCALL_SIGNAL_EVENT, monprm_paddr, 0);
 128 }
 129
 130 int
 131 hyperv_guid2str(const struct hyperv_guid *guid, char *buf, size_t sz)
 132 {
 133         const uint8_t *d = guid->hv_guid;
 134
 135         return snprintf(buf, sz, "%02x%02x%02x%02x-"
 136             "%02x%02x-%02x%02x-%02x%02x-"
 137             "%02x%02x%02x%02x%02x%02x",
 138             d[3], d[2], d[1], d[0],
 139             d[5], d[4], d[7], d[6], d[8], d[9],
 140             d[10], d[11], d[12], d[13], d[14], d[15]);
 141 }
 142
 143 static bool
 144 hyperv_identify(void)
 145 {
 146         u_int regs[4];
 147         unsigned int maxleaf;
 148
 149         if (vm_guest != VM_GUEST_HV)
 150                 return (false);
 151
 152         do_cpuid(CPUID_LEAF_HV_MAXLEAF, regs);
 153         maxleaf = regs[0];
 154         if (maxleaf < CPUID_LEAF_HV_LIMITS)
 155                 return (false);
 156
 157         do_cpuid(CPUID_LEAF_HV_INTERFACE, regs);
 158         if (regs[0] != CPUID_HV_IFACE_HYPERV)
 159                 return (false);
 160
 161         do_cpuid(CPUID_LEAF_HV_FEATURES, regs);
 162         if ((regs[0] & CPUID_HV_MSR_HYPERCALL) == 0) {
 163                 /*
 164                  * Hyper-V w/o Hypercall is impossible; someone
 165                  * is faking Hyper-V.
 166                  */
 167                 return (false);
 168         }
 169         hyperv_features = regs[0];
 170         hyperv_pm_features = regs[2];
 171         hyperv_features3 = regs[3];
 172
 173         do_cpuid(CPUID_LEAF_HV_IDENTITY, regs);
 174         hyperv_ver_major = regs[1] >> 16;
 175         printf("Hyper-V Version: %d.%d.%d [SP%d]\n",
 176             hyperv_ver_major, regs[1] & 0xffff, regs[0], regs[2]);
 177
 178         printf("  Features=0x%b\n", hyperv_features,
 179             "\020"
 180             "\001VPRUNTIME"     /* MSR_HV_VP_RUNTIME */
 181             "\002TMREFCNT"      /* MSR_HV_TIME_REF_COUNT */
 182             "\003SYNIC"         /* MSRs for SynIC */
 183             "\004SYNTM"         /* MSRs for SynTimer */
 184             "\005APIC"          /* MSR_HV_{EOI,ICR,TPR} */
 185             "\006HYPERCALL"     /* MSR_HV_{GUEST_OS_ID,HYPERCALL} */
 186             "\007VPINDEX"       /* MSR_HV_VP_INDEX */
 187             "\010RESET"         /* MSR_HV_RESET */
 188             "\011STATS"         /* MSR_HV_STATS_ */
 189             "\012REFTSC"        /* MSR_HV_REFERENCE_TSC */
 190             "\013IDLE"          /* MSR_HV_GUEST_IDLE */
 191             "\014TMFREQ"        /* MSR_HV_{TSC,APIC}_FREQUENCY */
 192             "\015DEBUG");       /* MSR_HV_SYNTH_DEBUG_ */
 193         printf("  PM Features=0x%b [C%u]\n",
 194             (hyperv_pm_features & ~CPUPM_HV_CSTATE_MASK),
 195             "\020"
 196             "\005C3HPET",       /* HPET is required for C3 state */
 197             CPUPM_HV_CSTATE(hyperv_pm_features));
 198         printf("  Features3=0x%b\n", hyperv_features3,
 199             "\020"
 200             "\001MWAIT"         /* MWAIT */
 201             "\002DEBUG"         /* guest debug support */
 202             "\003PERFMON"       /* performance monitor */
 203             "\004PCPUDPE"       /* physical CPU dynamic partition event */
 204             "\005XMMHC"         /* hypercall input through XMM regs */
 205             "\006IDLE"          /* guest idle support */
 206             "\007SLEEP"         /* hypervisor sleep support */
 207             "\010NUMA"          /* NUMA distance query support */
 208             "\011TMFREQ"        /* timer frequency query (TSC, LAPIC) */
 209             "\012SYNCMC"        /* inject synthetic machine checks */
 210             "\013CRASH"         /* MSRs for guest crash */
 211             "\014DEBUGMSR"      /* MSRs for guest debug */
 212             "\015NPIEP"         /* NPIEP */
 213             "\016HVDIS");       /* disabling hypervisor */
 214
 215         do_cpuid(CPUID_LEAF_HV_RECOMMENDS, regs);
 216         hyperv_recommends = regs[0];
 217         if (bootverbose)
 218                 printf("  Recommends: %08x %08x\n", regs[0], regs[1]);
 219
 220         do_cpuid(CPUID_LEAF_HV_LIMITS, regs);
 221         if (bootverbose) {
 222                 printf("  Limits: Vcpu:%d Lcpu:%d Int:%d\n",
 223                     regs[0], regs[1], regs[2]);
 224         }
 225
 226         if (maxleaf >= CPUID_LEAF_HV_HWFEATURES) {
 227                 do_cpuid(CPUID_LEAF_HV_HWFEATURES, regs);
 228                 if (bootverbose) {
 229                         printf("  HW Features: %08x, AMD: %08x\n",
 230                             regs[0], regs[3]);
 231                 }
 232         }
 233
 234         return (true);
 235 }
 236
 237 static void
 238 hyperv_init(void *dummy __unused)
 239 {
 240         if (!hyperv_identify()) {
 241                 /* Not Hyper-V; reset guest id to the generic one. */
 242                 if (vm_guest == VM_GUEST_HV)
 243                         vm_guest = VM_GUEST_VM;
 244                 return;
 245         }
 246
 247         /* Set guest id */
 248         wrmsr(MSR_HV_GUEST_OS_ID, MSR_HV_GUESTID_FREEBSD);
 249
 250         if (hyperv_features & CPUID_HV_MSR_TIME_REFCNT) {
 251                 /*
 252                  * Register Hyper-V timecounter.  This should be done as early
 253                  * as possible to let DELAY() work, since the 8254 PIT is not
 254                  * reliably emulated or even available.
 255                  */
 256                 tc_init(&hyperv_timecounter);
 257
 258                 /*
 259                  * Install 64 bits timecounter method for other modules
 260                  * to use.
 261                  */
 262                 hyperv_tc64 = hyperv_tc64_rdmsr;
 263         }
 264 }
 265 SYSINIT(hyperv_initialize, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, hyperv_init,
 266     NULL);
 267
 268 static void
 269 hypercall_memfree(void)
 270 {
 271         kmem_free((vm_offset_t)hypercall_context.hc_addr, PAGE_SIZE);
 272         hypercall_context.hc_addr = NULL;
 273 }
 274
 275 static void
 276 hypercall_create(void *arg __unused)
 277 {
 278         uint64_t hc, hc_orig;
 279
 280         if (vm_guest != VM_GUEST_HV)
 281                 return;
 282
 283         /*
 284          * NOTE:
 285          * - busdma(9), i.e. hyperv_dmamem APIs, can _not_ be used due to
 286          *   the NX bit.
 287          * - Assume kmem_malloc() returns properly aligned memory.
 288          */
 289         hypercall_context.hc_addr = (void *)kmem_malloc(PAGE_SIZE, M_EXEC |
 290             M_WAITOK);
 291         hypercall_context.hc_paddr = vtophys(hypercall_context.hc_addr);
 292
 293         /* Get the 'reserved' bits, which requires preservation. */
 294         hc_orig = rdmsr(MSR_HV_HYPERCALL);
 295
 296         /*
 297          * Setup the Hypercall page.
 298          *
 299          * NOTE: 'reserved' bits MUST be preserved.
 300          */
 301         hc = ((hypercall_context.hc_paddr >> PAGE_SHIFT) <<
 302             MSR_HV_HYPERCALL_PGSHIFT) |
 303             (hc_orig & MSR_HV_HYPERCALL_RSVD_MASK) |
 304             MSR_HV_HYPERCALL_ENABLE;
 305         wrmsr(MSR_HV_HYPERCALL, hc);
 306
 307         /*
 308          * Confirm that Hypercall page did get setup.
 309          */
 310         hc = rdmsr(MSR_HV_HYPERCALL);
 311         if ((hc & MSR_HV_HYPERCALL_ENABLE) == 0) {
 312                 printf("hyperv: Hypercall setup failed\n");
 313                 hypercall_memfree();
 314                 /* Can't perform any Hyper-V specific actions */
 315                 vm_guest = VM_GUEST_VM;
 316                 return;
 317         }
 318         if (bootverbose)
 319                 printf("hyperv: Hypercall created\n");
 320 }
 321 SYSINIT(hypercall_ctor, SI_SUB_DRIVERS, SI_ORDER_FIRST, hypercall_create, NULL);
 322
 323 static void
 324 hypercall_destroy(void *arg __unused)
 325 {
 326         uint64_t hc;
 327
 328         if (hypercall_context.hc_addr == NULL)
 329                 return;
 330
 331         /* Disable Hypercall */
 332         hc = rdmsr(MSR_HV_HYPERCALL);
 333         wrmsr(MSR_HV_HYPERCALL, (hc & MSR_HV_HYPERCALL_RSVD_MASK));
 334         hypercall_memfree();
 335
 336         if (bootverbose)
 337                 printf("hyperv: Hypercall destroyed\n");
 338 }
 339 SYSUNINIT(hypercall_dtor, SI_SUB_DRIVERS, SI_ORDER_FIRST, hypercall_destroy,
 340     NULL);