1 /*
2  * Copyright (C) 2011. Freescale Inc. All rights reserved.
3  *
4  * Authors:
5  *    Alexander Graf <agraf@suse.de>
6  *    Paul Mackerras <paulus@samba.org>
7  *
8  * Description:
9  *
10  * Hypercall handling for running PAPR guests in PR KVM on Book 3S
11  * processors.
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License, version 2, as
15  * published by the Free Software Foundation.
16  */
17 
18 #include <asm/uaccess.h>
19 #include <asm/kvm_ppc.h>
20 #include <asm/kvm_book3s.h>
21 
22 static unsigned long get_pteg_addr(struct kvm_vcpu *vcpu, long pte_index)
23 {
24 	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
25 	unsigned long pteg_addr;
26 
27 	pte_index <<= 4;
28 	pte_index &= ((1 << ((vcpu_book3s->sdr1 & 0x1f) + 11)) - 1) << 7 | 0x70;
29 	pteg_addr = vcpu_book3s->sdr1 & 0xfffffffffffc0000ULL;
30 	pteg_addr |= pte_index;
31 
32 	return pteg_addr;
33 }
34 
35 static int kvmppc_h_pr_enter(struct kvm_vcpu *vcpu)
36 {
37 	long flags = kvmppc_get_gpr(vcpu, 4);
38 	long pte_index = kvmppc_get_gpr(vcpu, 5);
39 	unsigned long pteg[2 * 8];
40 	unsigned long pteg_addr, i, *hpte;
41 
42 	pte_index &= ~7UL;
43 	pteg_addr = get_pteg_addr(vcpu, pte_index);
44 
45 	copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg));
46 	hpte = pteg;
47 
48 	if (likely((flags & H_EXACT) == 0)) {
49 		pte_index &= ~7UL;
50 		for (i = 0; ; ++i) {
51 			if (i == 8)
52 				return H_PTEG_FULL;
53 			if ((*hpte & HPTE_V_VALID) == 0)
54 				break;
55 			hpte += 2;
56 		}
57 	} else {
58 		i = kvmppc_get_gpr(vcpu, 5) & 7UL;
59 		hpte += i * 2;
60 	}
61 
62 	hpte[0] = kvmppc_get_gpr(vcpu, 6);
63 	hpte[1] = kvmppc_get_gpr(vcpu, 7);
64 	copy_to_user((void __user *)pteg_addr, pteg, sizeof(pteg));
65 	kvmppc_set_gpr(vcpu, 3, H_SUCCESS);
66 	kvmppc_set_gpr(vcpu, 4, pte_index | i);
67 
68 	return EMULATE_DONE;
69 }
70 
71 static int kvmppc_h_pr_remove(struct kvm_vcpu *vcpu)
72 {
73 	unsigned long flags= kvmppc_get_gpr(vcpu, 4);
74 	unsigned long pte_index = kvmppc_get_gpr(vcpu, 5);
75 	unsigned long avpn = kvmppc_get_gpr(vcpu, 6);
76 	unsigned long v = 0, pteg, rb;
77 	unsigned long pte[2];
78 
79 	pteg = get_pteg_addr(vcpu, pte_index);
80 	copy_from_user(pte, (void __user *)pteg, sizeof(pte));
81 
82 	if ((pte[0] & HPTE_V_VALID) == 0 ||
83 	    ((flags & H_AVPN) && (pte[0] & ~0x7fUL) != avpn) ||
84 	    ((flags & H_ANDCOND) && (pte[0] & avpn) != 0)) {
85 		kvmppc_set_gpr(vcpu, 3, H_NOT_FOUND);
86 		return EMULATE_DONE;
87 	}
88 
89 	copy_to_user((void __user *)pteg, &v, sizeof(v));
90 
91 	rb = compute_tlbie_rb(pte[0], pte[1], pte_index);
92 	vcpu->arch.mmu.tlbie(vcpu, rb, rb & 1 ? true : false);
93 
94 	kvmppc_set_gpr(vcpu, 3, H_SUCCESS);
95 	kvmppc_set_gpr(vcpu, 4, pte[0]);
96 	kvmppc_set_gpr(vcpu, 5, pte[1]);
97 
98 	return EMULATE_DONE;
99 }
100 
101 static int kvmppc_h_pr_protect(struct kvm_vcpu *vcpu)
102 {
103 	unsigned long flags = kvmppc_get_gpr(vcpu, 4);
104 	unsigned long pte_index = kvmppc_get_gpr(vcpu, 5);
105 	unsigned long avpn = kvmppc_get_gpr(vcpu, 6);
106 	unsigned long rb, pteg, r, v;
107 	unsigned long pte[2];
108 
109 	pteg = get_pteg_addr(vcpu, pte_index);
110 	copy_from_user(pte, (void __user *)pteg, sizeof(pte));
111 
112 	if ((pte[0] & HPTE_V_VALID) == 0 ||
113 	    ((flags & H_AVPN) && (pte[0] & ~0x7fUL) != avpn)) {
114 		kvmppc_set_gpr(vcpu, 3, H_NOT_FOUND);
115 		return EMULATE_DONE;
116 	}
117 
118 	v = pte[0];
119 	r = pte[1];
120 	r &= ~(HPTE_R_PP0 | HPTE_R_PP | HPTE_R_N | HPTE_R_KEY_HI |
121 	       HPTE_R_KEY_LO);
122 	r |= (flags << 55) & HPTE_R_PP0;
123 	r |= (flags << 48) & HPTE_R_KEY_HI;
124 	r |= flags & (HPTE_R_PP | HPTE_R_N | HPTE_R_KEY_LO);
125 
126 	pte[1] = r;
127 
128 	rb = compute_tlbie_rb(v, r, pte_index);
129 	vcpu->arch.mmu.tlbie(vcpu, rb, rb & 1 ? true : false);
130 	copy_to_user((void __user *)pteg, pte, sizeof(pte));
131 
132 	kvmppc_set_gpr(vcpu, 3, H_SUCCESS);
133 
134 	return EMULATE_DONE;
135 }
136 
137 int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd)
138 {
139 	switch (cmd) {
140 	case H_ENTER:
141 		return kvmppc_h_pr_enter(vcpu);
142 	case H_REMOVE:
143 		return kvmppc_h_pr_remove(vcpu);
144 	case H_PROTECT:
145 		return kvmppc_h_pr_protect(vcpu);
146 	case H_BULK_REMOVE:
147 		/* We just flush all PTEs, so user space can
148 		   handle the HPT modifications */
149 		kvmppc_mmu_pte_flush(vcpu, 0, 0);
150 		break;
151 	case H_CEDE:
152 		kvm_vcpu_block(vcpu);
153 		vcpu->stat.halt_wakeup++;
154 		return EMULATE_DONE;
155 	}
156 
157 	return EMULATE_FAIL;
158 }
159