summaryrefslogtreecommitdiff
path: root/arch/riscv/kvm/tlb.c
blob: 309d79b3e5cd58bc4235a6604bba6c77bb9aa469 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2022 Ventana Micro Systems Inc.
 */

#include <linux/bitmap.h>
#include <linux/cpumask.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/smp.h>
#include <linux/kvm_host.h>
#include <asm/cacheflush.h>
#include <asm/csr.h>
#include <asm/hwcap.h>
#include <asm/insn-def.h>

#define has_svinval()	\
	static_branch_unlikely(&riscv_isa_ext_keys[RISCV_ISA_EXT_KEY_SVINVAL])

void kvm_riscv_local_hfence_gvma_vmid_gpa(unsigned long vmid,
					  gpa_t gpa, gpa_t gpsz,
					  unsigned long order)
{
	gpa_t pos;

	if (PTRS_PER_PTE < (gpsz >> order)) {
		kvm_riscv_local_hfence_gvma_vmid_all(vmid);
		return;
	}

	if (has_svinval()) {
		asm volatile (SFENCE_W_INVAL() ::: "memory");
		for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order))
			asm volatile (HINVAL_GVMA(%0, %1)
			: : "r" (pos >> 2), "r" (vmid) : "memory");
		asm volatile (SFENCE_INVAL_IR() ::: "memory");
	} else {
		for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order))
			asm volatile (HFENCE_GVMA(%0, %1)
			: : "r" (pos >> 2), "r" (vmid) : "memory");
	}
}

void kvm_riscv_local_hfence_gvma_vmid_all(unsigned long vmid)
{
	asm volatile(HFENCE_GVMA(zero, %0) : : "r" (vmid) : "memory");
}

void kvm_riscv_local_hfence_gvma_gpa(gpa_t gpa, gpa_t gpsz,
				     unsigned long order)
{
	gpa_t pos;

	if (PTRS_PER_PTE < (gpsz >> order)) {
		kvm_riscv_local_hfence_gvma_all();
		return;
	}

	if (has_svinval()) {
		asm volatile (SFENCE_W_INVAL() ::: "memory");
		for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order))
			asm volatile(HINVAL_GVMA(%0, zero)
			: : "r" (pos >> 2) : "memory");
		asm volatile (SFENCE_INVAL_IR() ::: "memory");
	} else {
		for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order))
			asm volatile(HFENCE_GVMA(%0, zero)
			: : "r" (pos >> 2) : "memory");
	}
}

void kvm_riscv_local_hfence_gvma_all(void)
{
	asm volatile(HFENCE_GVMA(zero, zero) : : : "memory");
}

void kvm_riscv_local_hfence_vvma_asid_gva(unsigned long vmid,
					  unsigned long asid,
					  unsigned long gva,
					  unsigned long gvsz,
					  unsigned long order)
{
	unsigned long pos, hgatp;

	if (PTRS_PER_PTE < (gvsz >> order)) {
		kvm_riscv_local_hfence_vvma_asid_all(vmid, asid);
		return;
	}

	hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);

	if (has_svinval()) {
		asm volatile (SFENCE_W_INVAL() ::: "memory");
		for (pos = gva; pos < (gva + gvsz); pos += BIT(order))
			asm volatile(HINVAL_VVMA(%0, %1)
			: : "r" (pos), "r" (asid) : "memory");
		asm volatile (SFENCE_INVAL_IR() ::: "memory");
	} else {
		for (pos = gva; pos < (gva + gvsz); pos += BIT(order))
			asm volatile(HFENCE_VVMA(%0, %1)
			: : "r" (pos), "r" (asid) : "memory");
	}

	csr_write(CSR_HGATP, hgatp);
}

void kvm_riscv_local_hfence_vvma_asid_all(unsigned long vmid,
					  unsigned long asid)
{
	unsigned long hgatp;

	hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);

	asm volatile(HFENCE_VVMA(zero, %0) : : "r" (asid) : "memory");

	csr_write(CSR_HGATP, hgatp);
}

void kvm_riscv_local_hfence_vvma_gva(unsigned long vmid,
				     unsigned long gva, unsigned long gvsz,
				     unsigned long order)
{
	unsigned long pos, hgatp;

	if (PTRS_PER_PTE < (gvsz >> order)) {
		kvm_riscv_local_hfence_vvma_all(vmid);
		return;
	}

	hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);

	if (has_svinval()) {
		asm volatile (SFENCE_W_INVAL() ::: "memory");
		for (pos = gva; pos < (gva + gvsz); pos += BIT(order))
			asm volatile(HINVAL_VVMA(%0, zero)
			: : "r" (pos) : "memory");
		asm volatile (SFENCE_INVAL_IR() ::: "memory");
	} else {
		for (pos = gva; pos < (gva + gvsz); pos += BIT(order))
			asm volatile(HFENCE_VVMA(%0, zero)
			: : "r" (pos) : "memory");
	}

	csr_write(CSR_HGATP, hgatp);
}

void kvm_riscv_local_hfence_vvma_all(unsigned long vmid)
{
	unsigned long hgatp;

	hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);

	asm volatile(HFENCE_VVMA(zero, zero) : : : "memory");

	csr_write(CSR_HGATP, hgatp);
}

void kvm_riscv_local_tlb_sanitize(struct kvm_vcpu *vcpu)
{
	unsigned long vmid;

	if (!kvm_riscv_gstage_vmid_bits() ||
	    vcpu->arch.last_exit_cpu == vcpu->cpu)
		return;

	/*
	 * On RISC-V platforms with hardware VMID support, we share same
	 * VMID for all VCPUs of a particular Guest/VM. This means we might
	 * have stale G-stage TLB entries on the current Host CPU due to
	 * some other VCPU of the same Guest which ran previously on the
	 * current Host CPU.
	 *
	 * To cleanup stale TLB entries, we simply flush all G-stage TLB
	 * entries by VMID whenever underlying Host CPU changes for a VCPU.
	 */

	vmid = READ_ONCE(vcpu->kvm->arch.vmid.vmid);
	kvm_riscv_local_hfence_gvma_vmid_all(vmid);
}

void kvm_riscv_fence_i_process(struct kvm_vcpu *vcpu)
{
	local_flush_icache_all();
}

void kvm_riscv_hfence_gvma_vmid_all_process(struct kvm_vcpu *vcpu)
{
	struct kvm_vmid *vmid;

	vmid = &vcpu->kvm->arch.vmid;
	kvm_riscv_local_hfence_gvma_vmid_all(READ_ONCE(vmid->vmid));
}

void kvm_riscv_hfence_vvma_all_process(struct kvm_vcpu *vcpu)
{
	struct kvm_vmid *vmid;

	vmid = &vcpu->kvm->arch.vmid;
	kvm_riscv_local_hfence_vvma_all(READ_ONCE(vmid->vmid));
}

static bool vcpu_hfence_dequeue(struct kvm_vcpu *vcpu,
				struct kvm_riscv_hfence *out_data)
{
	bool ret = false;
	struct kvm_vcpu_arch *varch = &vcpu->arch;

	spin_lock(&varch->hfence_lock);

	if (varch->hfence_queue[varch->hfence_head].type) {
		memcpy(out_data, &varch->hfence_queue[varch->hfence_head],
		       sizeof(*out_data));
		varch->hfence_queue[varch->hfence_head].type = 0;

		varch->hfence_head++;
		if (varch->hfence_head == KVM_RISCV_VCPU_MAX_HFENCE)
			varch->hfence_head = 0;

		ret = true;
	}

	spin_unlock(&varch->hfence_lock);

	return ret;
}

static bool vcpu_hfence_enqueue(struct kvm_vcpu *vcpu,
				const struct kvm_riscv_hfence *data)
{
	bool ret = false;
	struct kvm_vcpu_arch *varch = &vcpu->arch;

	spin_lock(&varch->hfence_lock);

	if (!varch->hfence_queue[varch->hfence_tail].type) {
		memcpy(&varch->hfence_queue[varch->hfence_tail],
		       data, sizeof(*data));

		varch->hfence_tail++;
		if (varch->hfence_tail == KVM_RISCV_VCPU_MAX_HFENCE)
			varch->hfence_tail = 0;

		ret = true;
	}

	spin_unlock(&varch->hfence_lock);

	return ret;
}

void kvm_riscv_hfence_process(struct kvm_vcpu *vcpu)
{
	struct kvm_riscv_hfence d = { 0 };
	struct kvm_vmid *v = &vcpu->kvm->arch.vmid;

	while (vcpu_hfence_dequeue(vcpu, &d)) {
		switch (d.type) {
		case KVM_RISCV_HFENCE_UNKNOWN:
			break;
		case KVM_RISCV_HFENCE_GVMA_VMID_GPA:
			kvm_riscv_local_hfence_gvma_vmid_gpa(
						READ_ONCE(v->vmid),
						d.addr, d.size, d.order);
			break;
		case KVM_RISCV_HFENCE_VVMA_ASID_GVA:
			kvm_riscv_local_hfence_vvma_asid_gva(
						READ_ONCE(v->vmid), d.asid,
						d.addr, d.size, d.order);
			break;
		case KVM_RISCV_HFENCE_VVMA_ASID_ALL:
			kvm_riscv_local_hfence_vvma_asid_all(
						READ_ONCE(v->vmid), d.asid);
			break;
		case KVM_RISCV_HFENCE_VVMA_GVA:
			kvm_riscv_local_hfence_vvma_gva(
						READ_ONCE(v->vmid),
						d.addr, d.size, d.order);
			break;
		default:
			break;
		}
	}
}

static void make_xfence_request(struct kvm *kvm,
				unsigned long hbase, unsigned long hmask,
				unsigned int req, unsigned int fallback_req,
				const struct kvm_riscv_hfence *data)
{
	unsigned long i;
	struct kvm_vcpu *vcpu;
	unsigned int actual_req = req;
	DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);

	bitmap_clear(vcpu_mask, 0, KVM_MAX_VCPUS);
	kvm_for_each_vcpu(i, vcpu, kvm) {
		if (hbase != -1UL) {
			if (vcpu->vcpu_id < hbase)
				continue;
			if (!(hmask & (1UL << (vcpu->vcpu_id - hbase))))
				continue;
		}

		bitmap_set(vcpu_mask, i, 1);

		if (!data || !data->type)
			continue;

		/*
		 * Enqueue hfence data to VCPU hfence queue. If we don't
		 * have space in the VCPU hfence queue then fallback to
		 * a more conservative hfence request.
		 */
		if (!vcpu_hfence_enqueue(vcpu, data))
			actual_req = fallback_req;
	}

	kvm_make_vcpus_request_mask(kvm, actual_req, vcpu_mask);
}

void kvm_riscv_fence_i(struct kvm *kvm,
		       unsigned long hbase, unsigned long hmask)
{
	make_xfence_request(kvm, hbase, hmask, KVM_REQ_FENCE_I,
			    KVM_REQ_FENCE_I, NULL);
}

void kvm_riscv_hfence_gvma_vmid_gpa(struct kvm *kvm,
				    unsigned long hbase, unsigned long hmask,
				    gpa_t gpa, gpa_t gpsz,
				    unsigned long order)
{
	struct kvm_riscv_hfence data;

	data.type = KVM_RISCV_HFENCE_GVMA_VMID_GPA;
	data.asid = 0;
	data.addr = gpa;
	data.size = gpsz;
	data.order = order;
	make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE,
			    KVM_REQ_HFENCE_GVMA_VMID_ALL, &data);
}

void kvm_riscv_hfence_gvma_vmid_all(struct kvm *kvm,
				    unsigned long hbase, unsigned long hmask)
{
	make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_GVMA_VMID_ALL,
			    KVM_REQ_HFENCE_GVMA_VMID_ALL, NULL);
}

void kvm_riscv_hfence_vvma_asid_gva(struct kvm *kvm,
				    unsigned long hbase, unsigned long hmask,
				    unsigned long gva, unsigned long gvsz,
				    unsigned long order, unsigned long asid)
{
	struct kvm_riscv_hfence data;

	data.type = KVM_RISCV_HFENCE_VVMA_ASID_GVA;
	data.asid = asid;
	data.addr = gva;
	data.size = gvsz;
	data.order = order;
	make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE,
			    KVM_REQ_HFENCE_VVMA_ALL, &data);
}

void kvm_riscv_hfence_vvma_asid_all(struct kvm *kvm,
				    unsigned long hbase, unsigned long hmask,
				    unsigned long asid)
{
	struct kvm_riscv_hfence data;

	data.type = KVM_RISCV_HFENCE_VVMA_ASID_ALL;
	data.asid = asid;
	data.addr = data.size = data.order = 0;
	make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE,
			    KVM_REQ_HFENCE_VVMA_ALL, &data);
}

void kvm_riscv_hfence_vvma_gva(struct kvm *kvm,
			       unsigned long hbase, unsigned long hmask,
			       unsigned long gva, unsigned long gvsz,
			       unsigned long order)
{
	struct kvm_riscv_hfence data;

	data.type = KVM_RISCV_HFENCE_VVMA_GVA;
	data.asid = 0;
	data.addr = gva;
	data.size = gvsz;
	data.order = order;
	make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE,
			    KVM_REQ_HFENCE_VVMA_ALL, &data);
}

void kvm_riscv_hfence_vvma_all(struct kvm *kvm,
			       unsigned long hbase, unsigned long hmask)
{
	make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_VVMA_ALL,
			    KVM_REQ_HFENCE_VVMA_ALL, NULL);
}