hv.c revision 1f42248d724a413baaafd5f83a8f4746bc6f51a5
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 23 24#include <linux/kernel.h> 25#include <linux/mm.h> 26#include <linux/slab.h> 27#include <linux/vmalloc.h> 28#include <linux/hyperv.h> 29#include <linux/version.h> 30#include <asm/hyperv.h> 31#include "hyperv_vmbus.h" 32 33/* The one and only */ 34struct hv_context hv_context = { 35 .synic_initialized = false, 36 .hypercall_page = NULL, 37 .signal_event_param = NULL, 38 .signal_event_buffer = NULL, 39}; 40 41/* 42 * query_hypervisor_info - Get version info of the windows hypervisor 43 */ 44static int query_hypervisor_info(void) 45{ 46 unsigned int eax; 47 unsigned int ebx; 48 unsigned int ecx; 49 unsigned int edx; 50 unsigned int max_leaf; 51 unsigned int op; 52 53 /* 54 * Its assumed that this is called after confirming that Viridian 55 * is present. Query id and revision. 56 */ 57 eax = 0; 58 ebx = 0; 59 ecx = 0; 60 edx = 0; 61 op = HVCPUID_VENDOR_MAXFUNCTION; 62 cpuid(op, &eax, &ebx, &ecx, &edx); 63 64 max_leaf = eax; 65 66 if (max_leaf >= HVCPUID_VERSION) { 67 eax = 0; 68 ebx = 0; 69 ecx = 0; 70 edx = 0; 71 op = HVCPUID_VERSION; 72 cpuid(op, &eax, &ebx, &ecx, &edx); 73 pr_info("Hyper-V Host OS Build:%d-%d.%d-%d-%d.%d\n", 74 eax, 75 ebx >> 16, 76 ebx & 0xFFFF, 77 ecx, 78 edx >> 24, 79 edx & 0xFFFFFF); 80 } 81 return max_leaf; 82} 83 84/* 85 * do_hypercall- Invoke the specified hypercall 86 */ 87static u64 do_hypercall(u64 control, void *input, void *output) 88{ 89#ifdef CONFIG_X86_64 90 u64 hv_status = 0; 91 u64 input_address = (input) ? virt_to_phys(input) : 0; 92 u64 output_address = (output) ? virt_to_phys(output) : 0; 93 void *hypercall_page = hv_context.hypercall_page; 94 95 __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8"); 96 __asm__ __volatile__("call *%3" : "=a" (hv_status) : 97 "c" (control), "d" (input_address), 98 "m" (hypercall_page)); 99 100 return hv_status; 101 102#else 103 104 u32 control_hi = control >> 32; 105 u32 control_lo = control & 0xFFFFFFFF; 106 u32 hv_status_hi = 1; 107 u32 hv_status_lo = 1; 108 u64 input_address = (input) ? virt_to_phys(input) : 0; 109 u32 input_address_hi = input_address >> 32; 110 u32 input_address_lo = input_address & 0xFFFFFFFF; 111 u64 output_address = (output) ? virt_to_phys(output) : 0; 112 u32 output_address_hi = output_address >> 32; 113 u32 output_address_lo = output_address & 0xFFFFFFFF; 114 void *hypercall_page = hv_context.hypercall_page; 115 116 __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi), 117 "=a"(hv_status_lo) : "d" (control_hi), 118 "a" (control_lo), "b" (input_address_hi), 119 "c" (input_address_lo), "D"(output_address_hi), 120 "S"(output_address_lo), "m" (hypercall_page)); 121 122 return hv_status_lo | ((u64)hv_status_hi << 32); 123#endif /* !x86_64 */ 124} 125 126/* 127 * hv_init - Main initialization routine. 128 * 129 * This routine must be called before any other routines in here are called 130 */ 131int hv_init(void) 132{ 133 int max_leaf; 134 union hv_x64_msr_hypercall_contents hypercall_msr; 135 void *virtaddr = NULL; 136 137 memset(hv_context.synic_event_page, 0, sizeof(void *) * NR_CPUS); 138 memset(hv_context.synic_message_page, 0, 139 sizeof(void *) * NR_CPUS); 140 141 max_leaf = query_hypervisor_info(); 142 143 /* 144 * Write our OS ID. 145 */ 146 hv_context.guestid = generate_guest_id(0, LINUX_VERSION_CODE, 0); 147 wrmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid); 148 149 /* See if the hypercall page is already set */ 150 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 151 152 virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC); 153 154 if (!virtaddr) 155 goto cleanup; 156 157 hypercall_msr.enable = 1; 158 159 hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr); 160 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 161 162 /* Confirm that hypercall page did get setup. */ 163 hypercall_msr.as_uint64 = 0; 164 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 165 166 if (!hypercall_msr.enable) 167 goto cleanup; 168 169 hv_context.hypercall_page = virtaddr; 170 171 /* Setup the global signal event param for the signal event hypercall */ 172 hv_context.signal_event_buffer = 173 kmalloc(sizeof(struct hv_input_signal_event_buffer), 174 GFP_KERNEL); 175 if (!hv_context.signal_event_buffer) 176 goto cleanup; 177 178 hv_context.signal_event_param = 179 (struct hv_input_signal_event *) 180 (ALIGN((unsigned long) 181 hv_context.signal_event_buffer, 182 HV_HYPERCALL_PARAM_ALIGN)); 183 hv_context.signal_event_param->connectionid.asu32 = 0; 184 hv_context.signal_event_param->connectionid.u.id = 185 VMBUS_EVENT_CONNECTION_ID; 186 hv_context.signal_event_param->flag_number = 0; 187 hv_context.signal_event_param->rsvdz = 0; 188 189 return 0; 190 191cleanup: 192 if (virtaddr) { 193 if (hypercall_msr.enable) { 194 hypercall_msr.as_uint64 = 0; 195 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 196 } 197 198 vfree(virtaddr); 199 } 200 201 return -ENOTSUPP; 202} 203 204/* 205 * hv_cleanup - Cleanup routine. 206 * 207 * This routine is called normally during driver unloading or exiting. 208 */ 209void hv_cleanup(void) 210{ 211 union hv_x64_msr_hypercall_contents hypercall_msr; 212 213 /* Reset our OS id */ 214 wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); 215 216 kfree(hv_context.signal_event_buffer); 217 hv_context.signal_event_buffer = NULL; 218 hv_context.signal_event_param = NULL; 219 220 if (hv_context.hypercall_page) { 221 hypercall_msr.as_uint64 = 0; 222 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 223 vfree(hv_context.hypercall_page); 224 hv_context.hypercall_page = NULL; 225 } 226} 227 228/* 229 * hv_post_message - Post a message using the hypervisor message IPC. 230 * 231 * This involves a hypercall. 232 */ 233int hv_post_message(union hv_connection_id connection_id, 234 enum hv_message_type message_type, 235 void *payload, size_t payload_size) 236{ 237 struct aligned_input { 238 u64 alignment8; 239 struct hv_input_post_message msg; 240 }; 241 242 struct hv_input_post_message *aligned_msg; 243 u16 status; 244 unsigned long addr; 245 246 if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) 247 return -EMSGSIZE; 248 249 addr = (unsigned long)kmalloc(sizeof(struct aligned_input), GFP_ATOMIC); 250 if (!addr) 251 return -ENOMEM; 252 253 aligned_msg = (struct hv_input_post_message *) 254 (ALIGN(addr, HV_HYPERCALL_PARAM_ALIGN)); 255 256 aligned_msg->connectionid = connection_id; 257 aligned_msg->message_type = message_type; 258 aligned_msg->payload_size = payload_size; 259 memcpy((void *)aligned_msg->payload, payload, payload_size); 260 261 status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL) 262 & 0xFFFF; 263 264 kfree((void *)addr); 265 266 return status; 267} 268 269 270/* 271 * hv_signal_event - 272 * Signal an event on the specified connection using the hypervisor event IPC. 273 * 274 * This involves a hypercall. 275 */ 276u16 hv_signal_event(void *con_id) 277{ 278 u16 status; 279 280 status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF); 281 282 return status; 283} 284 285/* 286 * hv_synic_init - Initialize the Synthethic Interrupt Controller. 287 * 288 * If it is already initialized by another entity (ie x2v shim), we need to 289 * retrieve the initialized message and event pages. Otherwise, we create and 290 * initialize the message and event pages. 291 */ 292void hv_synic_init(void *irqarg) 293{ 294 u64 version; 295 union hv_synic_simp simp; 296 union hv_synic_siefp siefp; 297 union hv_synic_sint shared_sint; 298 union hv_synic_scontrol sctrl; 299 300 u32 irq_vector = *((u32 *)(irqarg)); 301 int cpu = smp_processor_id(); 302 303 if (!hv_context.hypercall_page) 304 return; 305 306 /* Check the version */ 307 rdmsrl(HV_X64_MSR_SVERSION, version); 308 309 hv_context.synic_message_page[cpu] = 310 (void *)get_zeroed_page(GFP_ATOMIC); 311 312 if (hv_context.synic_message_page[cpu] == NULL) { 313 pr_err("Unable to allocate SYNIC message page\n"); 314 goto cleanup; 315 } 316 317 hv_context.synic_event_page[cpu] = 318 (void *)get_zeroed_page(GFP_ATOMIC); 319 320 if (hv_context.synic_event_page[cpu] == NULL) { 321 pr_err("Unable to allocate SYNIC event page\n"); 322 goto cleanup; 323 } 324 325 /* Setup the Synic's message page */ 326 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 327 simp.simp_enabled = 1; 328 simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu]) 329 >> PAGE_SHIFT; 330 331 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 332 333 /* Setup the Synic's event page */ 334 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 335 siefp.siefp_enabled = 1; 336 siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu]) 337 >> PAGE_SHIFT; 338 339 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 340 341 /* Setup the shared SINT. */ 342 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 343 344 shared_sint.as_uint64 = 0; 345 shared_sint.vector = irq_vector; /* HV_SHARED_SINT_IDT_VECTOR + 0x20; */ 346 shared_sint.masked = false; 347 shared_sint.auto_eoi = false; 348 349 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 350 351 /* Enable the global synic bit */ 352 rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 353 sctrl.enable = 1; 354 355 wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 356 357 hv_context.synic_initialized = true; 358 return; 359 360cleanup: 361 if (hv_context.synic_event_page[cpu]) 362 free_page((unsigned long)hv_context.synic_event_page[cpu]); 363 364 if (hv_context.synic_message_page[cpu]) 365 free_page((unsigned long)hv_context.synic_message_page[cpu]); 366 return; 367} 368 369/* 370 * hv_synic_cleanup - Cleanup routine for hv_synic_init(). 371 */ 372void hv_synic_cleanup(void *arg) 373{ 374 union hv_synic_sint shared_sint; 375 union hv_synic_simp simp; 376 union hv_synic_siefp siefp; 377 int cpu = smp_processor_id(); 378 379 if (!hv_context.synic_initialized) 380 return; 381 382 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 383 384 shared_sint.masked = 1; 385 386 /* Need to correctly cleanup in the case of SMP!!! */ 387 /* Disable the interrupt */ 388 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 389 390 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 391 simp.simp_enabled = 0; 392 simp.base_simp_gpa = 0; 393 394 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 395 396 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 397 siefp.siefp_enabled = 0; 398 siefp.base_siefp_gpa = 0; 399 400 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 401 402 free_page((unsigned long)hv_context.synic_message_page[cpu]); 403 free_page((unsigned long)hv_context.synic_event_page[cpu]); 404} 405