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 */
query_hypervisor_presence(void)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 */
query_hypervisor_info(void)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 */
do_hypercall(u64 control,void * input,void * output)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 */
hv_init(void)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 */
hv_cleanup(void)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 */
hv_post_message(union hv_connection_id connection_id,enum hv_message_type message_type,void * payload,size_t payload_size)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 */
hv_signal_event(void)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 */
hv_synic_init(void * irqarg)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 */
hv_synic_cleanup(void * arg)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 }
508