drivers/staging/hv/hv.c

   1 /*
   2  * Copyright (c) 2009, Microsoft Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Authors:
  18  *   Haiyang Zhang <haiyangz@microsoft.com>
  19  *   Hank Janssen  <hjanssen@microsoft.com>
  20  *
  21  */
  22 #include <linux/kernel.h>
  23 #include <linux/mm.h>
  24 #include <linux/slab.h>
  25 #include <linux/vmalloc.h>
  26 #include "hv_api.h"
  27 #include "logging.h"
  28 #include "vmbus_private.h"
  29
  30 /* The one and only */
  31 struct hv_context hv_context = {
  32         .synic_initialized      = false,
  33         .hypercall_page         = NULL,
  34         .signal_event_param     = NULL,
  35         .signal_event_buffer    = NULL,
  36 };
  37
  38 /*
  39  * query_hypervisor_presence
  40  * - Query the cpuid for presence of windows hypervisor
  41  */
  42 static int query_hypervisor_presence(void)
  43 {
  44         unsigned int eax;
  45         unsigned int ebx;
  46         unsigned int ecx;
  47         unsigned int edx;
  48         unsigned int op;
  49
  50         eax = 0;
  51         ebx = 0;
  52         ecx = 0;
  53         edx = 0;
  54         op = HVCPUID_VERSION_FEATURES;
  55         cpuid(op, &eax, &ebx, &ecx, &edx);
  56
  57         return ecx & HV_PRESENT_BIT;
  58 }
  59
  60 /*
  61  * query_hypervisor_info - Get version info of the windows hypervisor
  62  */
  63 static int query_hypervisor_info(void)
  64 {
  65         unsigned int eax;
  66         unsigned int ebx;
  67         unsigned int ecx;
  68         unsigned int edx;
  69         unsigned int max_leaf;
  70         unsigned int op;
  71
  72         /*
  73         * Its assumed that this is called after confirming that Viridian
  74         * is present. Query id and revision.
  75         */
  76         eax = 0;
  77         ebx = 0;
  78         ecx = 0;
  79         edx = 0;
  80         op = HVCPUID_VENDOR_MAXFUNCTION;
  81         cpuid(op, &eax, &ebx, &ecx, &edx);
  82
  83         DPRINT_INFO(VMBUS, "Vendor ID: %c%c%c%c%c%c%c%c%c%c%c%c",
  84                     (ebx & 0xFF),
  85                     ((ebx >> 8) & 0xFF),
  86                     ((ebx >> 16) & 0xFF),
  87                     ((ebx >> 24) & 0xFF),
  88                     (ecx & 0xFF),
  89                     ((ecx >> 8) & 0xFF),
  90                     ((ecx >> 16) & 0xFF),
  91                     ((ecx >> 24) & 0xFF),
  92                     (edx & 0xFF),
  93                     ((edx >> 8) & 0xFF),
  94                     ((edx >> 16) & 0xFF),
  95                     ((edx >> 24) & 0xFF));
  96
  97         max_leaf = eax;
  98         eax = 0;
  99         ebx = 0;
 100         ecx = 0;
 101         edx = 0;
 102         op = HVCPUID_INTERFACE;
 103         cpuid(op, &eax, &ebx, &ecx, &edx);
 104
 105         DPRINT_INFO(VMBUS, "Interface ID: %c%c%c%c",
 106                     (eax & 0xFF),
 107                     ((eax >> 8) & 0xFF),
 108                     ((eax >> 16) & 0xFF),
 109                     ((eax >> 24) & 0xFF));
 110
 111         if (max_leaf >= HVCPUID_VERSION) {
 112                 eax = 0;
 113                 ebx = 0;
 114                 ecx = 0;
 115                 edx = 0;
 116                 op = HVCPUID_VERSION;
 117                 cpuid(op, &eax, &ebx, &ecx, &edx);
 118                 DPRINT_INFO(VMBUS, "OS Build:%d-%d.%d-%d-%d.%d",\
 119                             eax,
 120                             ebx >> 16,
 121                             ebx & 0xFFFF,
 122                             ecx,
 123                             edx >> 24,
 124                             edx & 0xFFFFFF);
 125         }
 126         return max_leaf;
 127 }
 128
 129 /*
 130  * do_hypercall- Invoke the specified hypercall
 131  */
 132 static u64 do_hypercall(u64 control, void *input, void *output)
 133 {
 134 #ifdef CONFIG_X86_64
 135         u64 hv_status = 0;
 136         u64 input_address = (input) ? virt_to_phys(input) : 0;
 137         u64 output_address = (output) ? virt_to_phys(output) : 0;
 138         volatile void *hypercall_page = hv_context.hypercall_page;
 139
 140         DPRINT_DBG(VMBUS, "Hypercall <control %llx input phys %llx virt %p "
 141                    "output phys %llx virt %p hypercall %p>",
 142                    control, input_address, input,
 143                    output_address, output, hypercall_page);
 144
 145         __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8");
 146         __asm__ __volatile__("call *%3" : "=a" (hv_status) :
 147                              "c" (control), "d" (input_address),
 148                              "m" (hypercall_page));
 149
 150         DPRINT_DBG(VMBUS, "Hypercall <return %llx>",  hv_status);
 151
 152         return hv_status;
 153
 154 #else
 155
 156         u32 control_hi = control >> 32;
 157         u32 control_lo = control & 0xFFFFFFFF;
 158         u32 hv_status_hi = 1;
 159         u32 hv_status_lo = 1;
 160         u64 input_address = (input) ? virt_to_phys(input) : 0;
 161         u32 input_address_hi = input_address >> 32;
 162         u32 input_address_lo = input_address & 0xFFFFFFFF;
 163         u64 output_address = (output) ? virt_to_phys(output) : 0;
 164         u32 output_address_hi = output_address >> 32;
 165         u32 output_address_lo = output_address & 0xFFFFFFFF;
 166         volatile void *hypercall_page = hv_context.hypercall_page;
 167
 168         DPRINT_DBG(VMBUS, "Hypercall <control %llx input %p output %p>",
 169                    control, input, output);
 170
 171         __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi),
 172                               "=a"(hv_status_lo) : "d" (control_hi),
 173                               "a" (control_lo), "b" (input_address_hi),
 174                               "c" (input_address_lo), "D"(output_address_hi),
 175                               "S"(output_address_lo), "m" (hypercall_page));
 176
 177         DPRINT_DBG(VMBUS, "Hypercall <return %llx>",
 178                    hv_status_lo | ((u64)hv_status_hi << 32));
 179
 180         return hv_status_lo | ((u64)hv_status_hi << 32);
 181 #endif /* !x86_64 */
 182 }
 183
 184 /*
 185  * hv_init - Main initialization routine.
 186  *
 187  * This routine must be called before any other routines in here are called
 188  */
 189 int hv_init(void)
 190 {
 191         int ret = 0;
 192         int max_leaf;
 193         union hv_x64_msr_hypercall_contents hypercall_msr;
 194         void *virtaddr = NULL;
 195
 196         memset(hv_context.synic_event_page, 0, sizeof(void *) * MAX_NUM_CPUS);
 197         memset(hv_context.synic_message_page, 0,
 198                sizeof(void *) * MAX_NUM_CPUS);
 199
 200         if (!query_hypervisor_presence()) {
 201                 DPRINT_ERR(VMBUS, "No Windows hypervisor detected!!");
 202                 goto Cleanup;
 203         }
 204
 205         DPRINT_INFO(VMBUS,
 206                     "Windows hypervisor detected! Retrieving more info...");
 207
 208         max_leaf = query_hypervisor_info();
 209         /* HvQueryHypervisorFeatures(maxLeaf); */
 210
 211         /*
 212          * We only support running on top of Hyper-V
 213          */
 214         rdmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid);
 215
 216         if (hv_context.guestid != 0) {
 217                 DPRINT_ERR(VMBUS, "Unknown guest id (0x%llx)!!",
 218                                 hv_context.guestid);
 219                 goto Cleanup;
 220         }
 221
 222         /* Write our OS info */
 223         wrmsrl(HV_X64_MSR_GUEST_OS_ID, HV_LINUX_GUEST_ID);
 224         hv_context.guestid = HV_LINUX_GUEST_ID;
 225
 226         /* See if the hypercall page is already set */
 227         rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
 228
 229         /*
 230         * Allocate the hypercall page memory
 231         * virtaddr = osd_page_alloc(1);
 232         */
 233         virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
 234
 235         if (!virtaddr) {
 236                 DPRINT_ERR(VMBUS,
 237                            "unable to allocate hypercall page!!");
 238                 goto Cleanup;
 239         }
 240
 241         hypercall_msr.enable = 1;
 242
 243         hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr);
 244         wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
 245
 246         /* Confirm that hypercall page did get setup. */
 247         hypercall_msr.as_uint64 = 0;
 248         rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
 249
 250         if (!hypercall_msr.enable) {
 251                 DPRINT_ERR(VMBUS, "unable to set hypercall page!!");
 252                 goto Cleanup;
 253         }
 254
 255         hv_context.hypercall_page = virtaddr;
 256
 257         DPRINT_INFO(VMBUS, "Hypercall page VA=%p, PA=0x%0llx",
 258                     hv_context.hypercall_page,
 259                     (u64)hypercall_msr.guest_physical_address << PAGE_SHIFT);
 260
 261         /* Setup the global signal event param for the signal event hypercall */
 262         hv_context.signal_event_buffer =
 263                         kmalloc(sizeof(struct hv_input_signal_event_buffer),
 264                                 GFP_KERNEL);
 265         if (!hv_context.signal_event_buffer)
 266                 goto Cleanup;
 267
 268         hv_context.signal_event_param =
 269                 (struct hv_input_signal_event *)
 270                         (ALIGN((unsigned long)
 271                                   hv_context.signal_event_buffer,
 272                                   HV_HYPERCALL_PARAM_ALIGN));
 273         hv_context.signal_event_param->connectionid.asu32 = 0;
 274         hv_context.signal_event_param->connectionid.u.id =
 275                                                 VMBUS_EVENT_CONNECTION_ID;
 276         hv_context.signal_event_param->flag_number = 0;
 277         hv_context.signal_event_param->rsvdz = 0;
 278
 279         return ret;
 280
 281 Cleanup:
 282         if (virtaddr) {
 283                 if (hypercall_msr.enable) {
 284                         hypercall_msr.as_uint64 = 0;
 285                         wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
 286                 }
 287
 288                 vfree(virtaddr);
 289         }
 290         ret = -1;
 291         return ret;
 292 }
 293
 294 /*
 295  * hv_cleanup - Cleanup routine.
 296  *
 297  * This routine is called normally during driver unloading or exiting.
 298  */
 299 void hv_cleanup(void)
 300 {
 301         union hv_x64_msr_hypercall_contents hypercall_msr;
 302
 303         kfree(hv_context.signal_event_buffer);
 304         hv_context.signal_event_buffer = NULL;
 305         hv_context.signal_event_param = NULL;
 306
 307         if (hv_context.hypercall_page) {
 308                 hypercall_msr.as_uint64 = 0;
 309                 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
 310                 vfree(hv_context.hypercall_page);
 311                 hv_context.hypercall_page = NULL;
 312         }
 313 }
 314
 315 /*
 316  * hv_post_message - Post a message using the hypervisor message IPC.
 317  *
 318  * This involves a hypercall.
 319  */
 320 u16 hv_post_message(union hv_connection_id connection_id,
 321                   enum hv_message_type message_type,
 322                   void *payload, size_t payload_size)
 323 {
 324         struct aligned_input {
 325                 u64 alignment8;
 326                 struct hv_input_post_message msg;
 327         };
 328
 329         struct hv_input_post_message *aligned_msg;
 330         u16 status;
 331         unsigned long addr;
 332
 333         if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
 334                 return -1;
 335
 336         addr = (unsigned long)kmalloc(sizeof(struct aligned_input), GFP_ATOMIC);
 337         if (!addr)
 338                 return -1;
 339
 340         aligned_msg = (struct hv_input_post_message *)
 341                         (ALIGN(addr, HV_HYPERCALL_PARAM_ALIGN));
 342
 343         aligned_msg->connectionid = connection_id;
 344         aligned_msg->message_type = message_type;
 345         aligned_msg->payload_size = payload_size;
 346         memcpy((void *)aligned_msg->payload, payload, payload_size);
 347
 348         status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL)
 349                 & 0xFFFF;
 350
 351         kfree((void *)addr);
 352
 353         return status;
 354 }
 355
 356
 357 /*
 358  * hv_signal_event -
 359  * Signal an event on the specified connection using the hypervisor event IPC.
 360  *
 361  * This involves a hypercall.
 362  */
 363 u16 hv_signal_event(void)
 364 {
 365         u16 status;
 366
 367         status = do_hypercall(HVCALL_SIGNAL_EVENT,
 368                                hv_context.signal_event_param,
 369                                NULL) & 0xFFFF;
 370         return status;
 371 }
 372
 373 /*
 374  * hv_synic_init - Initialize the Synthethic Interrupt Controller.
 375  *
 376  * If it is already initialized by another entity (ie x2v shim), we need to
 377  * retrieve the initialized message and event pages.  Otherwise, we create and
 378  * initialize the message and event pages.
 379  */
 380 void hv_synic_init(void *irqarg)
 381 {
 382         u64 version;
 383         union hv_synic_simp simp;
 384         union hv_synic_siefp siefp;
 385         union hv_synic_sint shared_sint;
 386         union hv_synic_scontrol sctrl;
 387
 388         u32 irq_vector = *((u32 *)(irqarg));
 389         int cpu = smp_processor_id();
 390
 391         if (!hv_context.hypercall_page)
 392                 return;
 393
 394         /* Check the version */
 395         rdmsrl(HV_X64_MSR_SVERSION, version);
 396
 397         DPRINT_INFO(VMBUS, "SynIC version: %llx", version);
 398
 399         hv_context.synic_message_page[cpu] =
 400                 (void *)get_zeroed_page(GFP_ATOMIC);
 401
 402         if (hv_context.synic_message_page[cpu] == NULL) {
 403                 DPRINT_ERR(VMBUS,
 404                            "unable to allocate SYNIC message page!!");
 405                 goto Cleanup;
 406         }
 407
 408         hv_context.synic_event_page[cpu] =
 409                 (void *)get_zeroed_page(GFP_ATOMIC);
 410
 411         if (hv_context.synic_event_page[cpu] == NULL) {
 412                 DPRINT_ERR(VMBUS,
 413                            "unable to allocate SYNIC event page!!");
 414                 goto Cleanup;
 415         }
 416
 417         /* Setup the Synic's message page */
 418         rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 419         simp.simp_enabled = 1;
 420         simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu])
 421                 >> PAGE_SHIFT;
 422
 423         DPRINT_DBG(VMBUS, "HV_X64_MSR_SIMP msr set to: %llx", simp.as_uint64);
 424
 425         wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 426
 427         /* Setup the Synic's event page */
 428         rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 429         siefp.siefp_enabled = 1;
 430         siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu])
 431                 >> PAGE_SHIFT;
 432
 433         DPRINT_DBG(VMBUS, "HV_X64_MSR_SIEFP msr set to: %llx", siefp.as_uint64);
 434
 435         wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 436
 437         /* Setup the interception SINT. */
 438         /* wrmsrl((HV_X64_MSR_SINT0 + HV_SYNIC_INTERCEPTION_SINT_INDEX), */
 439         /*        interceptionSint.as_uint64); */
 440
 441         /* Setup the shared SINT. */
 442         rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
 443
 444         shared_sint.as_uint64 = 0;
 445         shared_sint.vector = irq_vector; /* HV_SHARED_SINT_IDT_VECTOR + 0x20; */
 446         shared_sint.masked = false;
 447         shared_sint.auto_eoi = true;
 448
 449         DPRINT_DBG(VMBUS, "HV_X64_MSR_SINT1 msr set to: %llx",
 450                    shared_sint.as_uint64);
 451
 452         wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
 453
 454         /* Enable the global synic bit */
 455         rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
 456         sctrl.enable = 1;
 457
 458         wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
 459
 460         hv_context.synic_initialized = true;
 461         return;
 462
 463 Cleanup:
 464         if (hv_context.synic_event_page[cpu])
 465                 free_page((unsigned long)hv_context.synic_event_page[cpu]);
 466
 467         if (hv_context.synic_message_page[cpu])
 468                 free_page((unsigned long)hv_context.synic_message_page[cpu]);
 469         return;
 470 }
 471
 472 /*
 473  * hv_synic_cleanup - Cleanup routine for hv_synic_init().
 474  */
 475 void hv_synic_cleanup(void *arg)
 476 {
 477         union hv_synic_sint shared_sint;
 478         union hv_synic_simp simp;
 479         union hv_synic_siefp siefp;
 480         int cpu = smp_processor_id();
 481
 482         if (!hv_context.synic_initialized)
 483                 return;
 484
 485         rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
 486
 487         shared_sint.masked = 1;
 488
 489         /* Need to correctly cleanup in the case of SMP!!! */
 490         /* Disable the interrupt */
 491         wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
 492
 493         rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 494         simp.simp_enabled = 0;
 495         simp.base_simp_gpa = 0;
 496
 497         wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 498
 499         rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 500         siefp.siefp_enabled = 0;
 501         siefp.base_siefp_gpa = 0;
 502
 503         wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 504
 505         free_page((unsigned long)hv_context.synic_message_page[cpu]);
 506         free_page((unsigned long)hv_context.synic_event_page[cpu]);
 507 }