1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License, version 2, as
4  * published by the Free Software Foundation.
5  *
6  * This program is distributed in the hope that it will be useful,
7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
9  * GNU General Public License for more details.
10  *
11  * You should have received a copy of the GNU General Public License
12  * along with this program; if not, write to the Free Software
13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
14  *
15  * Copyright SUSE Linux Products GmbH 2010
16  *
17  * Authors: Alexander Graf <agraf@suse.de>
18  */
19 
20 #ifndef __ASM_KVM_BOOK3S_64_H__
21 #define __ASM_KVM_BOOK3S_64_H__
22 
23 #ifdef CONFIG_KVM_BOOK3S_PR
24 static inline struct kvmppc_book3s_shadow_vcpu *svcpu_get(struct kvm_vcpu *vcpu)
25 {
26 	preempt_disable();
27 	return &get_paca()->shadow_vcpu;
28 }
29 
30 static inline void svcpu_put(struct kvmppc_book3s_shadow_vcpu *svcpu)
31 {
32 	preempt_enable();
33 }
34 #endif
35 
36 #define SPAPR_TCE_SHIFT		12
37 
38 #ifdef CONFIG_KVM_BOOK3S_64_HV
39 #define KVM_DEFAULT_HPT_ORDER	24	/* 16MB HPT by default */
40 extern int kvm_hpt_order;		/* order of preallocated HPTs */
41 #endif
42 
43 #define VRMA_VSID	0x1ffffffUL	/* 1TB VSID reserved for VRMA */
44 
45 /*
46  * We use a lock bit in HPTE dword 0 to synchronize updates and
47  * accesses to each HPTE, and another bit to indicate non-present
48  * HPTEs.
49  */
50 #define HPTE_V_HVLOCK	0x40UL
51 #define HPTE_V_ABSENT	0x20UL
52 
53 static inline long try_lock_hpte(unsigned long *hpte, unsigned long bits)
54 {
55 	unsigned long tmp, old;
56 
57 	asm volatile("	ldarx	%0,0,%2\n"
58 		     "	and.	%1,%0,%3\n"
59 		     "	bne	2f\n"
60 		     "	ori	%0,%0,%4\n"
61 		     "  stdcx.	%0,0,%2\n"
62 		     "	beq+	2f\n"
63 		     "	li	%1,%3\n"
64 		     "2:	isync"
65 		     : "=&r" (tmp), "=&r" (old)
66 		     : "r" (hpte), "r" (bits), "i" (HPTE_V_HVLOCK)
67 		     : "cc", "memory");
68 	return old == 0;
69 }
70 
71 static inline unsigned long compute_tlbie_rb(unsigned long v, unsigned long r,
72 					     unsigned long pte_index)
73 {
74 	unsigned long rb, va_low;
75 
76 	rb = (v & ~0x7fUL) << 16;		/* AVA field */
77 	va_low = pte_index >> 3;
78 	if (v & HPTE_V_SECONDARY)
79 		va_low = ~va_low;
80 	/* xor vsid from AVA */
81 	if (!(v & HPTE_V_1TB_SEG))
82 		va_low ^= v >> 12;
83 	else
84 		va_low ^= v >> 24;
85 	va_low &= 0x7ff;
86 	if (v & HPTE_V_LARGE) {
87 		rb |= 1;			/* L field */
88 		if (cpu_has_feature(CPU_FTR_ARCH_206) &&
89 		    (r & 0xff000)) {
90 			/* non-16MB large page, must be 64k */
91 			/* (masks depend on page size) */
92 			rb |= 0x1000;		/* page encoding in LP field */
93 			rb |= (va_low & 0x7f) << 16; /* 7b of VA in AVA/LP field */
94 			rb |= (va_low & 0xfe);	/* AVAL field (P7 doesn't seem to care) */
95 		}
96 	} else {
97 		/* 4kB page */
98 		rb |= (va_low & 0x7ff) << 12;	/* remaining 11b of VA */
99 	}
100 	rb |= (v >> 54) & 0x300;		/* B field */
101 	return rb;
102 }
103 
104 static inline unsigned long hpte_page_size(unsigned long h, unsigned long l)
105 {
106 	/* only handle 4k, 64k and 16M pages for now */
107 	if (!(h & HPTE_V_LARGE))
108 		return 1ul << 12;		/* 4k page */
109 	if ((l & 0xf000) == 0x1000 && cpu_has_feature(CPU_FTR_ARCH_206))
110 		return 1ul << 16;		/* 64k page */
111 	if ((l & 0xff000) == 0)
112 		return 1ul << 24;		/* 16M page */
113 	return 0;				/* error */
114 }
115 
116 static inline unsigned long hpte_rpn(unsigned long ptel, unsigned long psize)
117 {
118 	return ((ptel & HPTE_R_RPN) & ~(psize - 1)) >> PAGE_SHIFT;
119 }
120 
121 static inline int hpte_is_writable(unsigned long ptel)
122 {
123 	unsigned long pp = ptel & (HPTE_R_PP0 | HPTE_R_PP);
124 
125 	return pp != PP_RXRX && pp != PP_RXXX;
126 }
127 
128 static inline unsigned long hpte_make_readonly(unsigned long ptel)
129 {
130 	if ((ptel & HPTE_R_PP0) || (ptel & HPTE_R_PP) == PP_RWXX)
131 		ptel = (ptel & ~HPTE_R_PP) | PP_RXXX;
132 	else
133 		ptel |= PP_RXRX;
134 	return ptel;
135 }
136 
137 static inline int hpte_cache_flags_ok(unsigned long ptel, unsigned long io_type)
138 {
139 	unsigned int wimg = ptel & HPTE_R_WIMG;
140 
141 	/* Handle SAO */
142 	if (wimg == (HPTE_R_W | HPTE_R_I | HPTE_R_M) &&
143 	    cpu_has_feature(CPU_FTR_ARCH_206))
144 		wimg = HPTE_R_M;
145 
146 	if (!io_type)
147 		return wimg == HPTE_R_M;
148 
149 	return (wimg & (HPTE_R_W | HPTE_R_I)) == io_type;
150 }
151 
152 /*
153  * Lock and read a linux PTE.  If it's present and writable, atomically
154  * set dirty and referenced bits and return the PTE, otherwise return 0.
155  */
156 static inline pte_t kvmppc_read_update_linux_pte(pte_t *p, int writing)
157 {
158 	pte_t pte, tmp;
159 
160 	/* wait until _PAGE_BUSY is clear then set it atomically */
161 	__asm__ __volatile__ (
162 		"1:	ldarx	%0,0,%3\n"
163 		"	andi.	%1,%0,%4\n"
164 		"	bne-	1b\n"
165 		"	ori	%1,%0,%4\n"
166 		"	stdcx.	%1,0,%3\n"
167 		"	bne-	1b"
168 		: "=&r" (pte), "=&r" (tmp), "=m" (*p)
169 		: "r" (p), "i" (_PAGE_BUSY)
170 		: "cc");
171 
172 	if (pte_present(pte)) {
173 		pte = pte_mkyoung(pte);
174 		if (writing && pte_write(pte))
175 			pte = pte_mkdirty(pte);
176 	}
177 
178 	*p = pte;	/* clears _PAGE_BUSY */
179 
180 	return pte;
181 }
182 
183 /* Return HPTE cache control bits corresponding to Linux pte bits */
184 static inline unsigned long hpte_cache_bits(unsigned long pte_val)
185 {
186 #if _PAGE_NO_CACHE == HPTE_R_I && _PAGE_WRITETHRU == HPTE_R_W
187 	return pte_val & (HPTE_R_W | HPTE_R_I);
188 #else
189 	return ((pte_val & _PAGE_NO_CACHE) ? HPTE_R_I : 0) +
190 		((pte_val & _PAGE_WRITETHRU) ? HPTE_R_W : 0);
191 #endif
192 }
193 
194 static inline bool hpte_read_permission(unsigned long pp, unsigned long key)
195 {
196 	if (key)
197 		return PP_RWRX <= pp && pp <= PP_RXRX;
198 	return 1;
199 }
200 
201 static inline bool hpte_write_permission(unsigned long pp, unsigned long key)
202 {
203 	if (key)
204 		return pp == PP_RWRW;
205 	return pp <= PP_RWRW;
206 }
207 
208 static inline int hpte_get_skey_perm(unsigned long hpte_r, unsigned long amr)
209 {
210 	unsigned long skey;
211 
212 	skey = ((hpte_r & HPTE_R_KEY_HI) >> 57) |
213 		((hpte_r & HPTE_R_KEY_LO) >> 9);
214 	return (amr >> (62 - 2 * skey)) & 3;
215 }
216 
217 static inline void lock_rmap(unsigned long *rmap)
218 {
219 	do {
220 		while (test_bit(KVMPPC_RMAP_LOCK_BIT, rmap))
221 			cpu_relax();
222 	} while (test_and_set_bit_lock(KVMPPC_RMAP_LOCK_BIT, rmap));
223 }
224 
225 static inline void unlock_rmap(unsigned long *rmap)
226 {
227 	__clear_bit_unlock(KVMPPC_RMAP_LOCK_BIT, rmap);
228 }
229 
230 static inline bool slot_is_aligned(struct kvm_memory_slot *memslot,
231 				   unsigned long pagesize)
232 {
233 	unsigned long mask = (pagesize >> PAGE_SHIFT) - 1;
234 
235 	if (pagesize <= PAGE_SIZE)
236 		return 1;
237 	return !(memslot->base_gfn & mask) && !(memslot->npages & mask);
238 }
239 
240 #endif /* __ASM_KVM_BOOK3S_64_H__ */
241