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 <linux/interrupt.h> 31 #include <asm/hyperv.h> 32 #include "hyperv_vmbus.h" 33 34 /* The one and only */ 35 struct hv_context hv_context = { 36 .synic_initialized = false, 37 .hypercall_page = NULL, 38 }; 39 40 /* 41 * query_hypervisor_info - Get version info of the windows hypervisor 42 */ 43 unsigned int host_info_eax; 44 unsigned int host_info_ebx; 45 unsigned int host_info_ecx; 46 unsigned int host_info_edx; 47 48 static int query_hypervisor_info(void) 49 { 50 unsigned int eax; 51 unsigned int ebx; 52 unsigned int ecx; 53 unsigned int edx; 54 unsigned int max_leaf; 55 unsigned int op; 56 57 /* 58 * Its assumed that this is called after confirming that Viridian 59 * is present. Query id and revision. 60 */ 61 eax = 0; 62 ebx = 0; 63 ecx = 0; 64 edx = 0; 65 op = HVCPUID_VENDOR_MAXFUNCTION; 66 cpuid(op, &eax, &ebx, &ecx, &edx); 67 68 max_leaf = eax; 69 70 if (max_leaf >= HVCPUID_VERSION) { 71 eax = 0; 72 ebx = 0; 73 ecx = 0; 74 edx = 0; 75 op = HVCPUID_VERSION; 76 cpuid(op, &eax, &ebx, &ecx, &edx); 77 host_info_eax = eax; 78 host_info_ebx = ebx; 79 host_info_ecx = ecx; 80 host_info_edx = edx; 81 } 82 return max_leaf; 83 } 84 85 /* 86 * do_hypercall- Invoke the specified hypercall 87 */ 88 static u64 do_hypercall(u64 control, void *input, void *output) 89 { 90 #ifdef CONFIG_X86_64 91 u64 hv_status = 0; 92 u64 input_address = (input) ? virt_to_phys(input) : 0; 93 u64 output_address = (output) ? virt_to_phys(output) : 0; 94 void *hypercall_page = hv_context.hypercall_page; 95 96 __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8"); 97 __asm__ __volatile__("call *%3" : "=a" (hv_status) : 98 "c" (control), "d" (input_address), 99 "m" (hypercall_page)); 100 101 return hv_status; 102 103 #else 104 105 u32 control_hi = control >> 32; 106 u32 control_lo = control & 0xFFFFFFFF; 107 u32 hv_status_hi = 1; 108 u32 hv_status_lo = 1; 109 u64 input_address = (input) ? virt_to_phys(input) : 0; 110 u32 input_address_hi = input_address >> 32; 111 u32 input_address_lo = input_address & 0xFFFFFFFF; 112 u64 output_address = (output) ? virt_to_phys(output) : 0; 113 u32 output_address_hi = output_address >> 32; 114 u32 output_address_lo = output_address & 0xFFFFFFFF; 115 void *hypercall_page = hv_context.hypercall_page; 116 117 __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi), 118 "=a"(hv_status_lo) : "d" (control_hi), 119 "a" (control_lo), "b" (input_address_hi), 120 "c" (input_address_lo), "D"(output_address_hi), 121 "S"(output_address_lo), "m" (hypercall_page)); 122 123 return hv_status_lo | ((u64)hv_status_hi << 32); 124 #endif /* !x86_64 */ 125 } 126 127 /* 128 * hv_init - Main initialization routine. 129 * 130 * This routine must be called before any other routines in here are called 131 */ 132 int hv_init(void) 133 { 134 int max_leaf; 135 union hv_x64_msr_hypercall_contents hypercall_msr; 136 void *virtaddr = NULL; 137 138 memset(hv_context.synic_event_page, 0, sizeof(void *) * NR_CPUS); 139 memset(hv_context.synic_message_page, 0, 140 sizeof(void *) * NR_CPUS); 141 memset(hv_context.vp_index, 0, 142 sizeof(int) * NR_CPUS); 143 memset(hv_context.event_dpc, 0, 144 sizeof(void *) * NR_CPUS); 145 146 max_leaf = query_hypervisor_info(); 147 148 /* 149 * Write our OS ID. 150 */ 151 hv_context.guestid = generate_guest_id(0, LINUX_VERSION_CODE, 0); 152 wrmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid); 153 154 /* See if the hypercall page is already set */ 155 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 156 157 virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC); 158 159 if (!virtaddr) 160 goto cleanup; 161 162 hypercall_msr.enable = 1; 163 164 hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr); 165 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 166 167 /* Confirm that hypercall page did get setup. */ 168 hypercall_msr.as_uint64 = 0; 169 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 170 171 if (!hypercall_msr.enable) 172 goto cleanup; 173 174 hv_context.hypercall_page = virtaddr; 175 176 return 0; 177 178 cleanup: 179 if (virtaddr) { 180 if (hypercall_msr.enable) { 181 hypercall_msr.as_uint64 = 0; 182 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 183 } 184 185 vfree(virtaddr); 186 } 187 188 return -ENOTSUPP; 189 } 190 191 /* 192 * hv_cleanup - Cleanup routine. 193 * 194 * This routine is called normally during driver unloading or exiting. 195 */ 196 void hv_cleanup(void) 197 { 198 union hv_x64_msr_hypercall_contents hypercall_msr; 199 200 /* Reset our OS id */ 201 wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); 202 203 if (hv_context.hypercall_page) { 204 hypercall_msr.as_uint64 = 0; 205 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 206 vfree(hv_context.hypercall_page); 207 hv_context.hypercall_page = NULL; 208 } 209 } 210 211 /* 212 * hv_post_message - Post a message using the hypervisor message IPC. 213 * 214 * This involves a hypercall. 215 */ 216 int hv_post_message(union hv_connection_id connection_id, 217 enum hv_message_type message_type, 218 void *payload, size_t payload_size) 219 { 220 struct aligned_input { 221 u64 alignment8; 222 struct hv_input_post_message msg; 223 }; 224 225 struct hv_input_post_message *aligned_msg; 226 u16 status; 227 unsigned long addr; 228 229 if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) 230 return -EMSGSIZE; 231 232 addr = (unsigned long)kmalloc(sizeof(struct aligned_input), GFP_ATOMIC); 233 if (!addr) 234 return -ENOMEM; 235 236 aligned_msg = (struct hv_input_post_message *) 237 (ALIGN(addr, HV_HYPERCALL_PARAM_ALIGN)); 238 239 aligned_msg->connectionid = connection_id; 240 aligned_msg->message_type = message_type; 241 aligned_msg->payload_size = payload_size; 242 memcpy((void *)aligned_msg->payload, payload, payload_size); 243 244 status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL) 245 & 0xFFFF; 246 247 kfree((void *)addr); 248 249 return status; 250 } 251 252 253 /* 254 * hv_signal_event - 255 * Signal an event on the specified connection using the hypervisor event IPC. 256 * 257 * This involves a hypercall. 258 */ 259 u16 hv_signal_event(void *con_id) 260 { 261 u16 status; 262 263 status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF); 264 265 return status; 266 } 267 268 /* 269 * hv_synic_init - Initialize the Synthethic Interrupt Controller. 270 * 271 * If it is already initialized by another entity (ie x2v shim), we need to 272 * retrieve the initialized message and event pages. Otherwise, we create and 273 * initialize the message and event pages. 274 */ 275 void hv_synic_init(void *arg) 276 { 277 u64 version; 278 union hv_synic_simp simp; 279 union hv_synic_siefp siefp; 280 union hv_synic_sint shared_sint; 281 union hv_synic_scontrol sctrl; 282 u64 vp_index; 283 284 int cpu = smp_processor_id(); 285 286 if (!hv_context.hypercall_page) 287 return; 288 289 /* Check the version */ 290 rdmsrl(HV_X64_MSR_SVERSION, version); 291 292 hv_context.event_dpc[cpu] = (struct tasklet_struct *) 293 kmalloc(sizeof(struct tasklet_struct), 294 GFP_ATOMIC); 295 if (hv_context.event_dpc[cpu] == NULL) { 296 pr_err("Unable to allocate event dpc\n"); 297 goto cleanup; 298 } 299 tasklet_init(hv_context.event_dpc[cpu], vmbus_on_event, cpu); 300 301 hv_context.synic_message_page[cpu] = 302 (void *)get_zeroed_page(GFP_ATOMIC); 303 304 if (hv_context.synic_message_page[cpu] == NULL) { 305 pr_err("Unable to allocate SYNIC message page\n"); 306 goto cleanup; 307 } 308 309 hv_context.synic_event_page[cpu] = 310 (void *)get_zeroed_page(GFP_ATOMIC); 311 312 if (hv_context.synic_event_page[cpu] == NULL) { 313 pr_err("Unable to allocate SYNIC event page\n"); 314 goto cleanup; 315 } 316 317 /* Setup the Synic's message page */ 318 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 319 simp.simp_enabled = 1; 320 simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu]) 321 >> PAGE_SHIFT; 322 323 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 324 325 /* Setup the Synic's event page */ 326 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 327 siefp.siefp_enabled = 1; 328 siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu]) 329 >> PAGE_SHIFT; 330 331 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 332 333 /* Setup the shared SINT. */ 334 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 335 336 shared_sint.as_uint64 = 0; 337 shared_sint.vector = HYPERVISOR_CALLBACK_VECTOR; 338 shared_sint.masked = false; 339 shared_sint.auto_eoi = true; 340 341 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 342 343 /* Enable the global synic bit */ 344 rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 345 sctrl.enable = 1; 346 347 wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 348 349 hv_context.synic_initialized = true; 350 351 /* 352 * Setup the mapping between Hyper-V's notion 353 * of cpuid and Linux' notion of cpuid. 354 * This array will be indexed using Linux cpuid. 355 */ 356 rdmsrl(HV_X64_MSR_VP_INDEX, vp_index); 357 hv_context.vp_index[cpu] = (u32)vp_index; 358 return; 359 360 cleanup: 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 */ 372 void 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