xref: /openbmc/linux/arch/powerpc/kvm/book3s_32_mmu.c (revision be709d48)
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 2009
16  *
17  * Authors: Alexander Graf <agraf@suse.de>
18  */
19 
20 #include <linux/types.h>
21 #include <linux/string.h>
22 #include <linux/kvm.h>
23 #include <linux/kvm_host.h>
24 #include <linux/highmem.h>
25 
26 #include <asm/kvm_ppc.h>
27 #include <asm/kvm_book3s.h>
28 
29 /* #define DEBUG_MMU */
30 /* #define DEBUG_MMU_PTE */
31 /* #define DEBUG_MMU_PTE_IP 0xfff14c40 */
32 
33 #ifdef DEBUG_MMU
34 #define dprintk(X...) printk(KERN_INFO X)
35 #else
36 #define dprintk(X...) do { } while(0)
37 #endif
38 
39 #ifdef DEBUG_MMU_PTE
40 #define dprintk_pte(X...) printk(KERN_INFO X)
41 #else
42 #define dprintk_pte(X...) do { } while(0)
43 #endif
44 
45 #define PTEG_FLAG_ACCESSED	0x00000100
46 #define PTEG_FLAG_DIRTY		0x00000080
47 #ifndef SID_SHIFT
48 #define SID_SHIFT		28
49 #endif
50 
51 static inline bool check_debug_ip(struct kvm_vcpu *vcpu)
52 {
53 #ifdef DEBUG_MMU_PTE_IP
54 	return vcpu->arch.regs.nip == DEBUG_MMU_PTE_IP;
55 #else
56 	return true;
57 #endif
58 }
59 
60 static inline u32 sr_vsid(u32 sr_raw)
61 {
62 	return sr_raw & 0x0fffffff;
63 }
64 
65 static inline bool sr_valid(u32 sr_raw)
66 {
67 	return (sr_raw & 0x80000000) ? false : true;
68 }
69 
70 static inline bool sr_ks(u32 sr_raw)
71 {
72 	return (sr_raw & 0x40000000) ? true: false;
73 }
74 
75 static inline bool sr_kp(u32 sr_raw)
76 {
77 	return (sr_raw & 0x20000000) ? true: false;
78 }
79 
80 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
81 					  struct kvmppc_pte *pte, bool data,
82 					  bool iswrite);
83 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
84 					     u64 *vsid);
85 
86 static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
87 {
88 	return kvmppc_get_sr(vcpu, (eaddr >> 28) & 0xf);
89 }
90 
91 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
92 					 bool data)
93 {
94 	u64 vsid;
95 	struct kvmppc_pte pte;
96 
97 	if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data, false))
98 		return pte.vpage;
99 
100 	kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
101 	return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
102 }
103 
104 static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
105 {
106 	kvmppc_set_msr(vcpu, 0);
107 }
108 
109 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvm_vcpu *vcpu,
110 				      u32 sre, gva_t eaddr,
111 				      bool primary)
112 {
113 	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
114 	u32 page, hash, pteg, htabmask;
115 	hva_t r;
116 
117 	page = (eaddr & 0x0FFFFFFF) >> 12;
118 	htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
119 
120 	hash = ((sr_vsid(sre) ^ page) << 6);
121 	if (!primary)
122 		hash = ~hash;
123 	hash &= htabmask;
124 
125 	pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
126 
127 	dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
128 		kvmppc_get_pc(vcpu), eaddr, vcpu_book3s->sdr1, pteg,
129 		sr_vsid(sre));
130 
131 	r = gfn_to_hva(vcpu->kvm, pteg >> PAGE_SHIFT);
132 	if (kvm_is_error_hva(r))
133 		return r;
134 	return r | (pteg & ~PAGE_MASK);
135 }
136 
137 static u32 kvmppc_mmu_book3s_32_get_ptem(u32 sre, gva_t eaddr, bool primary)
138 {
139 	return ((eaddr & 0x0fffffff) >> 22) | (sr_vsid(sre) << 7) |
140 	       (primary ? 0 : 0x40) | 0x80000000;
141 }
142 
143 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
144 					  struct kvmppc_pte *pte, bool data,
145 					  bool iswrite)
146 {
147 	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
148 	struct kvmppc_bat *bat;
149 	int i;
150 
151 	for (i = 0; i < 8; i++) {
152 		if (data)
153 			bat = &vcpu_book3s->dbat[i];
154 		else
155 			bat = &vcpu_book3s->ibat[i];
156 
157 		if (kvmppc_get_msr(vcpu) & MSR_PR) {
158 			if (!bat->vp)
159 				continue;
160 		} else {
161 			if (!bat->vs)
162 				continue;
163 		}
164 
165 		if (check_debug_ip(vcpu))
166 		{
167 			dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
168 				    data ? 'd' : 'i', i, eaddr, bat->bepi,
169 				    bat->bepi_mask);
170 		}
171 		if ((eaddr & bat->bepi_mask) == bat->bepi) {
172 			u64 vsid;
173 			kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
174 				eaddr >> SID_SHIFT, &vsid);
175 			vsid <<= 16;
176 			pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
177 
178 			pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
179 			pte->may_read = bat->pp;
180 			pte->may_write = bat->pp > 1;
181 			pte->may_execute = true;
182 			if (!pte->may_read) {
183 				printk(KERN_INFO "BAT is not readable!\n");
184 				continue;
185 			}
186 			if (iswrite && !pte->may_write) {
187 				dprintk_pte("BAT is read-only!\n");
188 				continue;
189 			}
190 
191 			return 0;
192 		}
193 	}
194 
195 	return -ENOENT;
196 }
197 
198 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
199 				     struct kvmppc_pte *pte, bool data,
200 				     bool iswrite, bool primary)
201 {
202 	u32 sre;
203 	hva_t ptegp;
204 	u32 pteg[16];
205 	u32 pte0, pte1;
206 	u32 ptem = 0;
207 	int i;
208 	int found = 0;
209 
210 	sre = find_sr(vcpu, eaddr);
211 
212 	dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
213 		    sr_vsid(sre), sre);
214 
215 	pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
216 
217 	ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu, sre, eaddr, primary);
218 	if (kvm_is_error_hva(ptegp)) {
219 		printk(KERN_INFO "KVM: Invalid PTEG!\n");
220 		goto no_page_found;
221 	}
222 
223 	ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
224 
225 	if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
226 		printk_ratelimited(KERN_ERR
227 			"KVM: Can't copy data from 0x%lx!\n", ptegp);
228 		goto no_page_found;
229 	}
230 
231 	for (i=0; i<16; i+=2) {
232 		pte0 = be32_to_cpu(pteg[i]);
233 		pte1 = be32_to_cpu(pteg[i + 1]);
234 		if (ptem == pte0) {
235 			u8 pp;
236 
237 			pte->raddr = (pte1 & ~(0xFFFULL)) | (eaddr & 0xFFF);
238 			pp = pte1 & 3;
239 
240 			if ((sr_kp(sre) &&  (kvmppc_get_msr(vcpu) & MSR_PR)) ||
241 			    (sr_ks(sre) && !(kvmppc_get_msr(vcpu) & MSR_PR)))
242 				pp |= 4;
243 
244 			pte->may_write = false;
245 			pte->may_read = false;
246 			pte->may_execute = true;
247 			switch (pp) {
248 				case 0:
249 				case 1:
250 				case 2:
251 				case 6:
252 					pte->may_write = true;
253 				case 3:
254 				case 5:
255 				case 7:
256 					pte->may_read = true;
257 					break;
258 			}
259 
260 			dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
261 				    pte0, pte1, pp);
262 			found = 1;
263 			break;
264 		}
265 	}
266 
267 	/* Update PTE C and A bits, so the guest's swapper knows we used the
268 	   page */
269 	if (found) {
270 		u32 pte_r = pte1;
271 		char __user *addr = (char __user *) (ptegp + (i+1) * sizeof(u32));
272 
273 		/*
274 		 * Use single-byte writes to update the HPTE, to
275 		 * conform to what real hardware does.
276 		 */
277 		if (pte->may_read && !(pte_r & PTEG_FLAG_ACCESSED)) {
278 			pte_r |= PTEG_FLAG_ACCESSED;
279 			put_user(pte_r >> 8, addr + 2);
280 		}
281 		if (iswrite && pte->may_write && !(pte_r & PTEG_FLAG_DIRTY)) {
282 			pte_r |= PTEG_FLAG_DIRTY;
283 			put_user(pte_r, addr + 3);
284 		}
285 		if (!pte->may_read || (iswrite && !pte->may_write))
286 			return -EPERM;
287 		return 0;
288 	}
289 
290 no_page_found:
291 
292 	if (check_debug_ip(vcpu)) {
293 		dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
294 			    to_book3s(vcpu)->sdr1, ptegp);
295 		for (i=0; i<16; i+=2) {
296 			dprintk_pte("   %02d: 0x%x - 0x%x (0x%x)\n",
297 				    i, be32_to_cpu(pteg[i]),
298 				    be32_to_cpu(pteg[i+1]), ptem);
299 		}
300 	}
301 
302 	return -ENOENT;
303 }
304 
305 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
306 				      struct kvmppc_pte *pte, bool data,
307 				      bool iswrite)
308 {
309 	int r;
310 	ulong mp_ea = vcpu->arch.magic_page_ea;
311 
312 	pte->eaddr = eaddr;
313 	pte->page_size = MMU_PAGE_4K;
314 
315 	/* Magic page override */
316 	if (unlikely(mp_ea) &&
317 	    unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
318 	    !(kvmppc_get_msr(vcpu) & MSR_PR)) {
319 		pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
320 		pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
321 		pte->raddr &= KVM_PAM;
322 		pte->may_execute = true;
323 		pte->may_read = true;
324 		pte->may_write = true;
325 
326 		return 0;
327 	}
328 
329 	r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data, iswrite);
330 	if (r < 0)
331 		r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
332 						   data, iswrite, true);
333 	if (r == -ENOENT)
334 		r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
335 						   data, iswrite, false);
336 
337 	return r;
338 }
339 
340 
341 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
342 {
343 	return kvmppc_get_sr(vcpu, srnum);
344 }
345 
346 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
347 					ulong value)
348 {
349 	kvmppc_set_sr(vcpu, srnum, value);
350 	kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
351 }
352 
353 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
354 {
355 	int i;
356 	struct kvm_vcpu *v;
357 
358 	/* flush this VA on all cpus */
359 	kvm_for_each_vcpu(i, v, vcpu->kvm)
360 		kvmppc_mmu_pte_flush(v, ea, 0x0FFFF000);
361 }
362 
363 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
364 					     u64 *vsid)
365 {
366 	ulong ea = esid << SID_SHIFT;
367 	u32 sr;
368 	u64 gvsid = esid;
369 	u64 msr = kvmppc_get_msr(vcpu);
370 
371 	if (msr & (MSR_DR|MSR_IR)) {
372 		sr = find_sr(vcpu, ea);
373 		if (sr_valid(sr))
374 			gvsid = sr_vsid(sr);
375 	}
376 
377 	/* In case we only have one of MSR_IR or MSR_DR set, let's put
378 	   that in the real-mode context (and hope RM doesn't access
379 	   high memory) */
380 	switch (msr & (MSR_DR|MSR_IR)) {
381 	case 0:
382 		*vsid = VSID_REAL | esid;
383 		break;
384 	case MSR_IR:
385 		*vsid = VSID_REAL_IR | gvsid;
386 		break;
387 	case MSR_DR:
388 		*vsid = VSID_REAL_DR | gvsid;
389 		break;
390 	case MSR_DR|MSR_IR:
391 		if (sr_valid(sr))
392 			*vsid = sr_vsid(sr);
393 		else
394 			*vsid = VSID_BAT | gvsid;
395 		break;
396 	default:
397 		BUG();
398 	}
399 
400 	if (msr & MSR_PR)
401 		*vsid |= VSID_PR;
402 
403 	return 0;
404 }
405 
406 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
407 {
408 	return true;
409 }
410 
411 
412 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
413 {
414 	struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
415 
416 	mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
417 	mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
418 	mmu->xlate = kvmppc_mmu_book3s_32_xlate;
419 	mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
420 	mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
421 	mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
422 	mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
423 	mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
424 
425 	mmu->slbmte = NULL;
426 	mmu->slbmfee = NULL;
427 	mmu->slbmfev = NULL;
428 	mmu->slbfee = NULL;
429 	mmu->slbie = NULL;
430 	mmu->slbia = NULL;
431 }
432