1/*
2 * Copyright (C) 2012,2013 - ARM Ltd
3 * Author: Marc Zyngier <marc.zyngier@arm.com>
4 *
5 * Derived from arch/arm/kvm/guest.c:
6 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
7 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
20 */
21
22#include <linux/errno.h>
23#include <linux/err.h>
24#include <linux/kvm_host.h>
25#include <linux/module.h>
26#include <linux/vmalloc.h>
27#include <linux/fs.h>
28#include <asm/cputype.h>
29#include <asm/uaccess.h>
30#include <asm/kvm.h>
31#include <asm/kvm_asm.h>
32#include <asm/kvm_emulate.h>
33#include <asm/kvm_coproc.h>
34
35struct kvm_stats_debugfs_item debugfs_entries[] = {
36	{ NULL }
37};
38
39int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
40{
41	return 0;
42}
43
44static u64 core_reg_offset_from_id(u64 id)
45{
46	return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
47}
48
49static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
50{
51	/*
52	 * Because the kvm_regs structure is a mix of 32, 64 and
53	 * 128bit fields, we index it as if it was a 32bit
54	 * array. Hence below, nr_regs is the number of entries, and
55	 * off the index in the "array".
56	 */
57	__u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
58	struct kvm_regs *regs = vcpu_gp_regs(vcpu);
59	int nr_regs = sizeof(*regs) / sizeof(__u32);
60	u32 off;
61
62	/* Our ID is an index into the kvm_regs struct. */
63	off = core_reg_offset_from_id(reg->id);
64	if (off >= nr_regs ||
65	    (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
66		return -ENOENT;
67
68	if (copy_to_user(uaddr, ((u32 *)regs) + off, KVM_REG_SIZE(reg->id)))
69		return -EFAULT;
70
71	return 0;
72}
73
74static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
75{
76	__u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
77	struct kvm_regs *regs = vcpu_gp_regs(vcpu);
78	int nr_regs = sizeof(*regs) / sizeof(__u32);
79	__uint128_t tmp;
80	void *valp = &tmp;
81	u64 off;
82	int err = 0;
83
84	/* Our ID is an index into the kvm_regs struct. */
85	off = core_reg_offset_from_id(reg->id);
86	if (off >= nr_regs ||
87	    (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
88		return -ENOENT;
89
90	if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
91		return -EINVAL;
92
93	if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
94		err = -EFAULT;
95		goto out;
96	}
97
98	if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
99		u32 mode = (*(u32 *)valp) & COMPAT_PSR_MODE_MASK;
100		switch (mode) {
101		case COMPAT_PSR_MODE_USR:
102		case COMPAT_PSR_MODE_FIQ:
103		case COMPAT_PSR_MODE_IRQ:
104		case COMPAT_PSR_MODE_SVC:
105		case COMPAT_PSR_MODE_ABT:
106		case COMPAT_PSR_MODE_UND:
107		case PSR_MODE_EL0t:
108		case PSR_MODE_EL1t:
109		case PSR_MODE_EL1h:
110			break;
111		default:
112			err = -EINVAL;
113			goto out;
114		}
115	}
116
117	memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
118out:
119	return err;
120}
121
122int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
123{
124	return -EINVAL;
125}
126
127int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
128{
129	return -EINVAL;
130}
131
132static unsigned long num_core_regs(void)
133{
134	return sizeof(struct kvm_regs) / sizeof(__u32);
135}
136
137/**
138 * ARM64 versions of the TIMER registers, always available on arm64
139 */
140
141#define NUM_TIMER_REGS 3
142
143static bool is_timer_reg(u64 index)
144{
145	switch (index) {
146	case KVM_REG_ARM_TIMER_CTL:
147	case KVM_REG_ARM_TIMER_CNT:
148	case KVM_REG_ARM_TIMER_CVAL:
149		return true;
150	}
151	return false;
152}
153
154static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
155{
156	if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
157		return -EFAULT;
158	uindices++;
159	if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
160		return -EFAULT;
161	uindices++;
162	if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
163		return -EFAULT;
164
165	return 0;
166}
167
168static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
169{
170	void __user *uaddr = (void __user *)(long)reg->addr;
171	u64 val;
172	int ret;
173
174	ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
175	if (ret != 0)
176		return -EFAULT;
177
178	return kvm_arm_timer_set_reg(vcpu, reg->id, val);
179}
180
181static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
182{
183	void __user *uaddr = (void __user *)(long)reg->addr;
184	u64 val;
185
186	val = kvm_arm_timer_get_reg(vcpu, reg->id);
187	return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)) ? -EFAULT : 0;
188}
189
190/**
191 * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
192 *
193 * This is for all registers.
194 */
195unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
196{
197	return num_core_regs() + kvm_arm_num_sys_reg_descs(vcpu)
198                + NUM_TIMER_REGS;
199}
200
201/**
202 * kvm_arm_copy_reg_indices - get indices of all registers.
203 *
204 * We do core registers right here, then we apppend system regs.
205 */
206int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
207{
208	unsigned int i;
209	const u64 core_reg = KVM_REG_ARM64 | KVM_REG_SIZE_U64 | KVM_REG_ARM_CORE;
210	int ret;
211
212	for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) {
213		if (put_user(core_reg | i, uindices))
214			return -EFAULT;
215		uindices++;
216	}
217
218	ret = copy_timer_indices(vcpu, uindices);
219	if (ret)
220		return ret;
221	uindices += NUM_TIMER_REGS;
222
223	return kvm_arm_copy_sys_reg_indices(vcpu, uindices);
224}
225
226int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
227{
228	/* We currently use nothing arch-specific in upper 32 bits */
229	if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
230		return -EINVAL;
231
232	/* Register group 16 means we want a core register. */
233	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
234		return get_core_reg(vcpu, reg);
235
236	if (is_timer_reg(reg->id))
237		return get_timer_reg(vcpu, reg);
238
239	return kvm_arm_sys_reg_get_reg(vcpu, reg);
240}
241
242int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
243{
244	/* We currently use nothing arch-specific in upper 32 bits */
245	if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
246		return -EINVAL;
247
248	/* Register group 16 means we set a core register. */
249	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
250		return set_core_reg(vcpu, reg);
251
252	if (is_timer_reg(reg->id))
253		return set_timer_reg(vcpu, reg);
254
255	return kvm_arm_sys_reg_set_reg(vcpu, reg);
256}
257
258int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
259				  struct kvm_sregs *sregs)
260{
261	return -EINVAL;
262}
263
264int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
265				  struct kvm_sregs *sregs)
266{
267	return -EINVAL;
268}
269
270int __attribute_const__ kvm_target_cpu(void)
271{
272	unsigned long implementor = read_cpuid_implementor();
273	unsigned long part_number = read_cpuid_part_number();
274
275	switch (implementor) {
276	case ARM_CPU_IMP_ARM:
277		switch (part_number) {
278		case ARM_CPU_PART_AEM_V8:
279			return KVM_ARM_TARGET_AEM_V8;
280		case ARM_CPU_PART_FOUNDATION:
281			return KVM_ARM_TARGET_FOUNDATION_V8;
282		case ARM_CPU_PART_CORTEX_A53:
283			return KVM_ARM_TARGET_CORTEX_A53;
284		case ARM_CPU_PART_CORTEX_A57:
285			return KVM_ARM_TARGET_CORTEX_A57;
286		};
287		break;
288	case ARM_CPU_IMP_APM:
289		switch (part_number) {
290		case APM_CPU_PART_POTENZA:
291			return KVM_ARM_TARGET_XGENE_POTENZA;
292		};
293		break;
294	};
295
296	return -EINVAL;
297}
298
299int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
300{
301	int target = kvm_target_cpu();
302
303	if (target < 0)
304		return -ENODEV;
305
306	memset(init, 0, sizeof(*init));
307
308	/*
309	 * For now, we don't return any features.
310	 * In future, we might use features to return target
311	 * specific features available for the preferred
312	 * target type.
313	 */
314	init->target = (__u32)target;
315
316	return 0;
317}
318
319int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
320{
321	return -EINVAL;
322}
323
324int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
325{
326	return -EINVAL;
327}
328
329int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
330				  struct kvm_translation *tr)
331{
332	return -EINVAL;
333}
334