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 rdmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid); 168 169 if (hv_context.guestid != 0) 170 goto cleanup; 171 172 /* Write our OS info */ 173 wrmsrl(HV_X64_MSR_GUEST_OS_ID, HV_LINUX_GUEST_ID); 174 hv_context.guestid = HV_LINUX_GUEST_ID; 175 176 /* See if the hypercall page is already set */ 177 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 178 179 virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC); 180 181 if (!virtaddr) 182 goto cleanup; 183 184 hypercall_msr.enable = 1; 185 186 hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr); 187 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 188 189 /* Confirm that hypercall page did get setup. */ 190 hypercall_msr.as_uint64 = 0; 191 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 192 193 if (!hypercall_msr.enable) 194 goto cleanup; 195 196 hv_context.hypercall_page = virtaddr; 197 198 /* Setup the global signal event param for the signal event hypercall */ 199 hv_context.signal_event_buffer = 200 kmalloc(sizeof(struct hv_input_signal_event_buffer), 201 GFP_KERNEL); 202 if (!hv_context.signal_event_buffer) 203 goto cleanup; 204 205 hv_context.signal_event_param = 206 (struct hv_input_signal_event *) 207 (ALIGN((unsigned long) 208 hv_context.signal_event_buffer, 209 HV_HYPERCALL_PARAM_ALIGN)); 210 hv_context.signal_event_param->connectionid.asu32 = 0; 211 hv_context.signal_event_param->connectionid.u.id = 212 VMBUS_EVENT_CONNECTION_ID; 213 hv_context.signal_event_param->flag_number = 0; 214 hv_context.signal_event_param->rsvdz = 0; 215 216 return 0; 217 218 cleanup: 219 if (virtaddr) { 220 if (hypercall_msr.enable) { 221 hypercall_msr.as_uint64 = 0; 222 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 223 } 224 225 vfree(virtaddr); 226 } 227 228 return -ENOTSUPP; 229 } 230 231 /* 232 * hv_cleanup - Cleanup routine. 233 * 234 * This routine is called normally during driver unloading or exiting. 235 */ 236 void hv_cleanup(void) 237 { 238 union hv_x64_msr_hypercall_contents hypercall_msr; 239 240 kfree(hv_context.signal_event_buffer); 241 hv_context.signal_event_buffer = NULL; 242 hv_context.signal_event_param = NULL; 243 244 if (hv_context.hypercall_page) { 245 hypercall_msr.as_uint64 = 0; 246 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 247 vfree(hv_context.hypercall_page); 248 hv_context.hypercall_page = NULL; 249 } 250 } 251 252 /* 253 * hv_post_message - Post a message using the hypervisor message IPC. 254 * 255 * This involves a hypercall. 256 */ 257 u16 hv_post_message(union hv_connection_id connection_id, 258 enum hv_message_type message_type, 259 void *payload, size_t payload_size) 260 { 261 struct aligned_input { 262 u64 alignment8; 263 struct hv_input_post_message msg; 264 }; 265 266 struct hv_input_post_message *aligned_msg; 267 u16 status; 268 unsigned long addr; 269 270 if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) 271 return -EMSGSIZE; 272 273 addr = (unsigned long)kmalloc(sizeof(struct aligned_input), GFP_ATOMIC); 274 if (!addr) 275 return -ENOMEM; 276 277 aligned_msg = (struct hv_input_post_message *) 278 (ALIGN(addr, HV_HYPERCALL_PARAM_ALIGN)); 279 280 aligned_msg->connectionid = connection_id; 281 aligned_msg->message_type = message_type; 282 aligned_msg->payload_size = payload_size; 283 memcpy((void *)aligned_msg->payload, payload, payload_size); 284 285 status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL) 286 & 0xFFFF; 287 288 kfree((void *)addr); 289 290 return status; 291 } 292 293 294 /* 295 * hv_signal_event - 296 * Signal an event on the specified connection using the hypervisor event IPC. 297 * 298 * This involves a hypercall. 299 */ 300 u16 hv_signal_event(void) 301 { 302 u16 status; 303 304 status = do_hypercall(HVCALL_SIGNAL_EVENT, 305 hv_context.signal_event_param, 306 NULL) & 0xFFFF; 307 return status; 308 } 309 310 /* 311 * hv_synic_init - Initialize the Synthethic Interrupt Controller. 312 * 313 * If it is already initialized by another entity (ie x2v shim), we need to 314 * retrieve the initialized message and event pages. Otherwise, we create and 315 * initialize the message and event pages. 316 */ 317 void hv_synic_init(void *irqarg) 318 { 319 u64 version; 320 union hv_synic_simp simp; 321 union hv_synic_siefp siefp; 322 union hv_synic_sint shared_sint; 323 union hv_synic_scontrol sctrl; 324 325 u32 irq_vector = *((u32 *)(irqarg)); 326 int cpu = smp_processor_id(); 327 328 if (!hv_context.hypercall_page) 329 return; 330 331 /* Check the version */ 332 rdmsrl(HV_X64_MSR_SVERSION, version); 333 334 hv_context.synic_message_page[cpu] = 335 (void *)get_zeroed_page(GFP_ATOMIC); 336 337 if (hv_context.synic_message_page[cpu] == NULL) { 338 pr_err("Unable to allocate SYNIC message page\n"); 339 goto cleanup; 340 } 341 342 hv_context.synic_event_page[cpu] = 343 (void *)get_zeroed_page(GFP_ATOMIC); 344 345 if (hv_context.synic_event_page[cpu] == NULL) { 346 pr_err("Unable to allocate SYNIC event page\n"); 347 goto cleanup; 348 } 349 350 /* Setup the Synic's message page */ 351 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 352 simp.simp_enabled = 1; 353 simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu]) 354 >> PAGE_SHIFT; 355 356 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 357 358 /* Setup the Synic's event page */ 359 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 360 siefp.siefp_enabled = 1; 361 siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu]) 362 >> PAGE_SHIFT; 363 364 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 365 366 /* Setup the shared SINT. */ 367 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 368 369 shared_sint.as_uint64 = 0; 370 shared_sint.vector = irq_vector; /* HV_SHARED_SINT_IDT_VECTOR + 0x20; */ 371 shared_sint.masked = false; 372 shared_sint.auto_eoi = false; 373 374 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 375 376 /* Enable the global synic bit */ 377 rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 378 sctrl.enable = 1; 379 380 wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 381 382 hv_context.synic_initialized = true; 383 return; 384 385 cleanup: 386 if (hv_context.synic_event_page[cpu]) 387 free_page((unsigned long)hv_context.synic_event_page[cpu]); 388 389 if (hv_context.synic_message_page[cpu]) 390 free_page((unsigned long)hv_context.synic_message_page[cpu]); 391 return; 392 } 393 394 /* 395 * hv_synic_cleanup - Cleanup routine for hv_synic_init(). 396 */ 397 void hv_synic_cleanup(void *arg) 398 { 399 union hv_synic_sint shared_sint; 400 union hv_synic_simp simp; 401 union hv_synic_siefp siefp; 402 int cpu = smp_processor_id(); 403 404 if (!hv_context.synic_initialized) 405 return; 406 407 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 408 409 shared_sint.masked = 1; 410 411 /* Need to correctly cleanup in the case of SMP!!! */ 412 /* Disable the interrupt */ 413 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 414 415 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 416 simp.simp_enabled = 0; 417 simp.base_simp_gpa = 0; 418 419 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 420 421 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 422 siefp.siefp_enabled = 0; 423 siefp.base_siefp_gpa = 0; 424 425 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 426 427 free_page((unsigned long)hv_context.synic_message_page[cpu]); 428 free_page((unsigned long)hv_context.synic_event_page[cpu]); 429 } 430