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 <asm/hyperv.h> 30 #include "hyperv_vmbus.h" 31 32 /* The one and only */ 33 struct hv_context hv_context = { 34 .synic_initialized = false, 35 .hypercall_page = NULL, 36 .signal_event_param = NULL, 37 .signal_event_buffer = NULL, 38 }; 39 40 /* 41 * query_hypervisor_presence 42 * - Query the cpuid for presence of windows hypervisor 43 */ 44 static int query_hypervisor_presence(void) 45 { 46 unsigned int eax; 47 unsigned int ebx; 48 unsigned int ecx; 49 unsigned int edx; 50 unsigned int op; 51 52 eax = 0; 53 ebx = 0; 54 ecx = 0; 55 edx = 0; 56 op = HVCPUID_VERSION_FEATURES; 57 cpuid(op, &eax, &ebx, &ecx, &edx); 58 59 return ecx & HV_PRESENT_BIT; 60 } 61 62 /* 63 * query_hypervisor_info - Get version info of the windows hypervisor 64 */ 65 static int query_hypervisor_info(void) 66 { 67 unsigned int eax; 68 unsigned int ebx; 69 unsigned int ecx; 70 unsigned int edx; 71 unsigned int max_leaf; 72 unsigned int op; 73 74 /* 75 * Its assumed that this is called after confirming that Viridian 76 * is present. Query id and revision. 77 */ 78 eax = 0; 79 ebx = 0; 80 ecx = 0; 81 edx = 0; 82 op = HVCPUID_VENDOR_MAXFUNCTION; 83 cpuid(op, &eax, &ebx, &ecx, &edx); 84 85 max_leaf = eax; 86 87 if (max_leaf >= HVCPUID_VERSION) { 88 eax = 0; 89 ebx = 0; 90 ecx = 0; 91 edx = 0; 92 op = HVCPUID_VERSION; 93 cpuid(op, &eax, &ebx, &ecx, &edx); 94 pr_info("Hyper-V Host OS Build:%d-%d.%d-%d-%d.%d\n", 95 eax, 96 ebx >> 16, 97 ebx & 0xFFFF, 98 ecx, 99 edx >> 24, 100 edx & 0xFFFFFF); 101 } 102 return max_leaf; 103 } 104 105 /* 106 * do_hypercall- Invoke the specified hypercall 107 */ 108 static u64 do_hypercall(u64 control, void *input, void *output) 109 { 110 #ifdef CONFIG_X86_64 111 u64 hv_status = 0; 112 u64 input_address = (input) ? virt_to_phys(input) : 0; 113 u64 output_address = (output) ? virt_to_phys(output) : 0; 114 void *hypercall_page = hv_context.hypercall_page; 115 116 __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8"); 117 __asm__ __volatile__("call *%3" : "=a" (hv_status) : 118 "c" (control), "d" (input_address), 119 "m" (hypercall_page)); 120 121 return hv_status; 122 123 #else 124 125 u32 control_hi = control >> 32; 126 u32 control_lo = control & 0xFFFFFFFF; 127 u32 hv_status_hi = 1; 128 u32 hv_status_lo = 1; 129 u64 input_address = (input) ? virt_to_phys(input) : 0; 130 u32 input_address_hi = input_address >> 32; 131 u32 input_address_lo = input_address & 0xFFFFFFFF; 132 u64 output_address = (output) ? virt_to_phys(output) : 0; 133 u32 output_address_hi = output_address >> 32; 134 u32 output_address_lo = output_address & 0xFFFFFFFF; 135 void *hypercall_page = hv_context.hypercall_page; 136 137 __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi), 138 "=a"(hv_status_lo) : "d" (control_hi), 139 "a" (control_lo), "b" (input_address_hi), 140 "c" (input_address_lo), "D"(output_address_hi), 141 "S"(output_address_lo), "m" (hypercall_page)); 142 143 return hv_status_lo | ((u64)hv_status_hi << 32); 144 #endif /* !x86_64 */ 145 } 146 147 /* 148 * hv_init - Main initialization routine. 149 * 150 * This routine must be called before any other routines in here are called 151 */ 152 int hv_init(void) 153 { 154 int max_leaf; 155 union hv_x64_msr_hypercall_contents hypercall_msr; 156 void *virtaddr = NULL; 157 158 memset(hv_context.synic_event_page, 0, sizeof(void *) * MAX_NUM_CPUS); 159 memset(hv_context.synic_message_page, 0, 160 sizeof(void *) * MAX_NUM_CPUS); 161 162 if (!query_hypervisor_presence()) 163 goto cleanup; 164 165 max_leaf = query_hypervisor_info(); 166 167 /* Write our OS info */ 168 wrmsrl(HV_X64_MSR_GUEST_OS_ID, HV_LINUX_GUEST_ID); 169 hv_context.guestid = HV_LINUX_GUEST_ID; 170 171 /* See if the hypercall page is already set */ 172 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 173 174 virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC); 175 176 if (!virtaddr) 177 goto cleanup; 178 179 hypercall_msr.enable = 1; 180 181 hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr); 182 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 183 184 /* Confirm that hypercall page did get setup. */ 185 hypercall_msr.as_uint64 = 0; 186 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 187 188 if (!hypercall_msr.enable) 189 goto cleanup; 190 191 hv_context.hypercall_page = virtaddr; 192 193 /* Setup the global signal event param for the signal event hypercall */ 194 hv_context.signal_event_buffer = 195 kmalloc(sizeof(struct hv_input_signal_event_buffer), 196 GFP_KERNEL); 197 if (!hv_context.signal_event_buffer) 198 goto cleanup; 199 200 hv_context.signal_event_param = 201 (struct hv_input_signal_event *) 202 (ALIGN((unsigned long) 203 hv_context.signal_event_buffer, 204 HV_HYPERCALL_PARAM_ALIGN)); 205 hv_context.signal_event_param->connectionid.asu32 = 0; 206 hv_context.signal_event_param->connectionid.u.id = 207 VMBUS_EVENT_CONNECTION_ID; 208 hv_context.signal_event_param->flag_number = 0; 209 hv_context.signal_event_param->rsvdz = 0; 210 211 return 0; 212 213 cleanup: 214 if (virtaddr) { 215 if (hypercall_msr.enable) { 216 hypercall_msr.as_uint64 = 0; 217 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 218 } 219 220 vfree(virtaddr); 221 } 222 223 return -ENOTSUPP; 224 } 225 226 /* 227 * hv_cleanup - Cleanup routine. 228 * 229 * This routine is called normally during driver unloading or exiting. 230 */ 231 void hv_cleanup(void) 232 { 233 union hv_x64_msr_hypercall_contents hypercall_msr; 234 235 /* Reset our OS id */ 236 wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); 237 238 kfree(hv_context.signal_event_buffer); 239 hv_context.signal_event_buffer = NULL; 240 hv_context.signal_event_param = NULL; 241 242 if (hv_context.hypercall_page) { 243 hypercall_msr.as_uint64 = 0; 244 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 245 vfree(hv_context.hypercall_page); 246 hv_context.hypercall_page = NULL; 247 } 248 } 249 250 /* 251 * hv_post_message - Post a message using the hypervisor message IPC. 252 * 253 * This involves a hypercall. 254 */ 255 u16 hv_post_message(union hv_connection_id connection_id, 256 enum hv_message_type message_type, 257 void *payload, size_t payload_size) 258 { 259 struct aligned_input { 260 u64 alignment8; 261 struct hv_input_post_message msg; 262 }; 263 264 struct hv_input_post_message *aligned_msg; 265 u16 status; 266 unsigned long addr; 267 268 if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) 269 return -EMSGSIZE; 270 271 addr = (unsigned long)kmalloc(sizeof(struct aligned_input), GFP_ATOMIC); 272 if (!addr) 273 return -ENOMEM; 274 275 aligned_msg = (struct hv_input_post_message *) 276 (ALIGN(addr, HV_HYPERCALL_PARAM_ALIGN)); 277 278 aligned_msg->connectionid = connection_id; 279 aligned_msg->message_type = message_type; 280 aligned_msg->payload_size = payload_size; 281 memcpy((void *)aligned_msg->payload, payload, payload_size); 282 283 status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL) 284 & 0xFFFF; 285 286 kfree((void *)addr); 287 288 return status; 289 } 290 291 292 /* 293 * hv_signal_event - 294 * Signal an event on the specified connection using the hypervisor event IPC. 295 * 296 * This involves a hypercall. 297 */ 298 u16 hv_signal_event(void) 299 { 300 u16 status; 301 302 status = do_hypercall(HVCALL_SIGNAL_EVENT, 303 hv_context.signal_event_param, 304 NULL) & 0xFFFF; 305 return status; 306 } 307 308 /* 309 * hv_synic_init - Initialize the Synthethic Interrupt Controller. 310 * 311 * If it is already initialized by another entity (ie x2v shim), we need to 312 * retrieve the initialized message and event pages. Otherwise, we create and 313 * initialize the message and event pages. 314 */ 315 void hv_synic_init(void *irqarg) 316 { 317 u64 version; 318 union hv_synic_simp simp; 319 union hv_synic_siefp siefp; 320 union hv_synic_sint shared_sint; 321 union hv_synic_scontrol sctrl; 322 323 u32 irq_vector = *((u32 *)(irqarg)); 324 int cpu = smp_processor_id(); 325 326 if (!hv_context.hypercall_page) 327 return; 328 329 /* Check the version */ 330 rdmsrl(HV_X64_MSR_SVERSION, version); 331 332 hv_context.synic_message_page[cpu] = 333 (void *)get_zeroed_page(GFP_ATOMIC); 334 335 if (hv_context.synic_message_page[cpu] == NULL) { 336 pr_err("Unable to allocate SYNIC message page\n"); 337 goto cleanup; 338 } 339 340 hv_context.synic_event_page[cpu] = 341 (void *)get_zeroed_page(GFP_ATOMIC); 342 343 if (hv_context.synic_event_page[cpu] == NULL) { 344 pr_err("Unable to allocate SYNIC event page\n"); 345 goto cleanup; 346 } 347 348 /* Setup the Synic's message page */ 349 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 350 simp.simp_enabled = 1; 351 simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu]) 352 >> PAGE_SHIFT; 353 354 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 355 356 /* Setup the Synic's event page */ 357 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 358 siefp.siefp_enabled = 1; 359 siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu]) 360 >> PAGE_SHIFT; 361 362 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 363 364 /* Setup the shared SINT. */ 365 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 366 367 shared_sint.as_uint64 = 0; 368 shared_sint.vector = irq_vector; /* HV_SHARED_SINT_IDT_VECTOR + 0x20; */ 369 shared_sint.masked = false; 370 shared_sint.auto_eoi = false; 371 372 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 373 374 /* Enable the global synic bit */ 375 rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 376 sctrl.enable = 1; 377 378 wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 379 380 hv_context.synic_initialized = true; 381 return; 382 383 cleanup: 384 if (hv_context.synic_event_page[cpu]) 385 free_page((unsigned long)hv_context.synic_event_page[cpu]); 386 387 if (hv_context.synic_message_page[cpu]) 388 free_page((unsigned long)hv_context.synic_message_page[cpu]); 389 return; 390 } 391 392 /* 393 * hv_synic_cleanup - Cleanup routine for hv_synic_init(). 394 */ 395 void hv_synic_cleanup(void *arg) 396 { 397 union hv_synic_sint shared_sint; 398 union hv_synic_simp simp; 399 union hv_synic_siefp siefp; 400 int cpu = smp_processor_id(); 401 402 if (!hv_context.synic_initialized) 403 return; 404 405 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 406 407 shared_sint.masked = 1; 408 409 /* Need to correctly cleanup in the case of SMP!!! */ 410 /* Disable the interrupt */ 411 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 412 413 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 414 simp.simp_enabled = 0; 415 simp.base_simp_gpa = 0; 416 417 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 418 419 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 420 siefp.siefp_enabled = 0; 421 siefp.base_siefp_gpa = 0; 422 423 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 424 425 free_page((unsigned long)hv_context.synic_message_page[cpu]); 426 free_page((unsigned long)hv_context.synic_event_page[cpu]); 427 } 428