xref: /openbmc/linux/arch/powerpc/kvm/book3s_32_mmu.c (revision 4f6cce39)
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/tlbflush.h>
27 #include <asm/kvm_ppc.h>
28 #include <asm/kvm_book3s.h>
29 
30 /* #define DEBUG_MMU */
31 /* #define DEBUG_MMU_PTE */
32 /* #define DEBUG_MMU_PTE_IP 0xfff14c40 */
33 
34 #ifdef DEBUG_MMU
35 #define dprintk(X...) printk(KERN_INFO X)
36 #else
37 #define dprintk(X...) do { } while(0)
38 #endif
39 
40 #ifdef DEBUG_MMU_PTE
41 #define dprintk_pte(X...) printk(KERN_INFO X)
42 #else
43 #define dprintk_pte(X...) do { } while(0)
44 #endif
45 
46 #define PTEG_FLAG_ACCESSED	0x00000100
47 #define PTEG_FLAG_DIRTY		0x00000080
48 #ifndef SID_SHIFT
49 #define SID_SHIFT		28
50 #endif
51 
52 static inline bool check_debug_ip(struct kvm_vcpu *vcpu)
53 {
54 #ifdef DEBUG_MMU_PTE_IP
55 	return vcpu->arch.pc == DEBUG_MMU_PTE_IP;
56 #else
57 	return true;
58 #endif
59 }
60 
61 static inline u32 sr_vsid(u32 sr_raw)
62 {
63 	return sr_raw & 0x0fffffff;
64 }
65 
66 static inline bool sr_valid(u32 sr_raw)
67 {
68 	return (sr_raw & 0x80000000) ? false : true;
69 }
70 
71 static inline bool sr_ks(u32 sr_raw)
72 {
73 	return (sr_raw & 0x40000000) ? true: false;
74 }
75 
76 static inline bool sr_kp(u32 sr_raw)
77 {
78 	return (sr_raw & 0x20000000) ? true: false;
79 }
80 
81 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
82 					  struct kvmppc_pte *pte, bool data,
83 					  bool iswrite);
84 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
85 					     u64 *vsid);
86 
87 static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
88 {
89 	return kvmppc_get_sr(vcpu, (eaddr >> 28) & 0xf);
90 }
91 
92 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
93 					 bool data)
94 {
95 	u64 vsid;
96 	struct kvmppc_pte pte;
97 
98 	if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data, false))
99 		return pte.vpage;
100 
101 	kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
102 	return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
103 }
104 
105 static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
106 {
107 	kvmppc_set_msr(vcpu, 0);
108 }
109 
110 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvm_vcpu *vcpu,
111 				      u32 sre, gva_t eaddr,
112 				      bool primary)
113 {
114 	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
115 	u32 page, hash, pteg, htabmask;
116 	hva_t r;
117 
118 	page = (eaddr & 0x0FFFFFFF) >> 12;
119 	htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
120 
121 	hash = ((sr_vsid(sre) ^ page) << 6);
122 	if (!primary)
123 		hash = ~hash;
124 	hash &= htabmask;
125 
126 	pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
127 
128 	dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
129 		kvmppc_get_pc(vcpu), eaddr, vcpu_book3s->sdr1, pteg,
130 		sr_vsid(sre));
131 
132 	r = gfn_to_hva(vcpu->kvm, pteg >> PAGE_SHIFT);
133 	if (kvm_is_error_hva(r))
134 		return r;
135 	return r | (pteg & ~PAGE_MASK);
136 }
137 
138 static u32 kvmppc_mmu_book3s_32_get_ptem(u32 sre, gva_t eaddr, bool primary)
139 {
140 	return ((eaddr & 0x0fffffff) >> 22) | (sr_vsid(sre) << 7) |
141 	       (primary ? 0 : 0x40) | 0x80000000;
142 }
143 
144 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
145 					  struct kvmppc_pte *pte, bool data,
146 					  bool iswrite)
147 {
148 	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
149 	struct kvmppc_bat *bat;
150 	int i;
151 
152 	for (i = 0; i < 8; i++) {
153 		if (data)
154 			bat = &vcpu_book3s->dbat[i];
155 		else
156 			bat = &vcpu_book3s->ibat[i];
157 
158 		if (kvmppc_get_msr(vcpu) & MSR_PR) {
159 			if (!bat->vp)
160 				continue;
161 		} else {
162 			if (!bat->vs)
163 				continue;
164 		}
165 
166 		if (check_debug_ip(vcpu))
167 		{
168 			dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
169 				    data ? 'd' : 'i', i, eaddr, bat->bepi,
170 				    bat->bepi_mask);
171 		}
172 		if ((eaddr & bat->bepi_mask) == bat->bepi) {
173 			u64 vsid;
174 			kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
175 				eaddr >> SID_SHIFT, &vsid);
176 			vsid <<= 16;
177 			pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
178 
179 			pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
180 			pte->may_read = bat->pp;
181 			pte->may_write = bat->pp > 1;
182 			pte->may_execute = true;
183 			if (!pte->may_read) {
184 				printk(KERN_INFO "BAT is not readable!\n");
185 				continue;
186 			}
187 			if (iswrite && !pte->may_write) {
188 				dprintk_pte("BAT is read-only!\n");
189 				continue;
190 			}
191 
192 			return 0;
193 		}
194 	}
195 
196 	return -ENOENT;
197 }
198 
199 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
200 				     struct kvmppc_pte *pte, bool data,
201 				     bool iswrite, bool primary)
202 {
203 	u32 sre;
204 	hva_t ptegp;
205 	u32 pteg[16];
206 	u32 pte0, pte1;
207 	u32 ptem = 0;
208 	int i;
209 	int found = 0;
210 
211 	sre = find_sr(vcpu, eaddr);
212 
213 	dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
214 		    sr_vsid(sre), sre);
215 
216 	pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
217 
218 	ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu, sre, eaddr, primary);
219 	if (kvm_is_error_hva(ptegp)) {
220 		printk(KERN_INFO "KVM: Invalid PTEG!\n");
221 		goto no_page_found;
222 	}
223 
224 	ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
225 
226 	if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
227 		printk_ratelimited(KERN_ERR
228 			"KVM: Can't copy data from 0x%lx!\n", ptegp);
229 		goto no_page_found;
230 	}
231 
232 	for (i=0; i<16; i+=2) {
233 		pte0 = be32_to_cpu(pteg[i]);
234 		pte1 = be32_to_cpu(pteg[i + 1]);
235 		if (ptem == pte0) {
236 			u8 pp;
237 
238 			pte->raddr = (pte1 & ~(0xFFFULL)) | (eaddr & 0xFFF);
239 			pp = pte1 & 3;
240 
241 			if ((sr_kp(sre) &&  (kvmppc_get_msr(vcpu) & MSR_PR)) ||
242 			    (sr_ks(sre) && !(kvmppc_get_msr(vcpu) & MSR_PR)))
243 				pp |= 4;
244 
245 			pte->may_write = false;
246 			pte->may_read = false;
247 			pte->may_execute = true;
248 			switch (pp) {
249 				case 0:
250 				case 1:
251 				case 2:
252 				case 6:
253 					pte->may_write = true;
254 				case 3:
255 				case 5:
256 				case 7:
257 					pte->may_read = true;
258 					break;
259 			}
260 
261 			dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
262 				    pte0, pte1, pp);
263 			found = 1;
264 			break;
265 		}
266 	}
267 
268 	/* Update PTE C and A bits, so the guest's swapper knows we used the
269 	   page */
270 	if (found) {
271 		u32 pte_r = pte1;
272 		char __user *addr = (char __user *) (ptegp + (i+1) * sizeof(u32));
273 
274 		/*
275 		 * Use single-byte writes to update the HPTE, to
276 		 * conform to what real hardware does.
277 		 */
278 		if (pte->may_read && !(pte_r & PTEG_FLAG_ACCESSED)) {
279 			pte_r |= PTEG_FLAG_ACCESSED;
280 			put_user(pte_r >> 8, addr + 2);
281 		}
282 		if (iswrite && pte->may_write && !(pte_r & PTEG_FLAG_DIRTY)) {
283 			pte_r |= PTEG_FLAG_DIRTY;
284 			put_user(pte_r, addr + 3);
285 		}
286 		if (!pte->may_read || (iswrite && !pte->may_write))
287 			return -EPERM;
288 		return 0;
289 	}
290 
291 no_page_found:
292 
293 	if (check_debug_ip(vcpu)) {
294 		dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
295 			    to_book3s(vcpu)->sdr1, ptegp);
296 		for (i=0; i<16; i+=2) {
297 			dprintk_pte("   %02d: 0x%x - 0x%x (0x%x)\n",
298 				    i, be32_to_cpu(pteg[i]),
299 				    be32_to_cpu(pteg[i+1]), ptem);
300 		}
301 	}
302 
303 	return -ENOENT;
304 }
305 
306 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
307 				      struct kvmppc_pte *pte, bool data,
308 				      bool iswrite)
309 {
310 	int r;
311 	ulong mp_ea = vcpu->arch.magic_page_ea;
312 
313 	pte->eaddr = eaddr;
314 	pte->page_size = MMU_PAGE_4K;
315 
316 	/* Magic page override */
317 	if (unlikely(mp_ea) &&
318 	    unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
319 	    !(kvmppc_get_msr(vcpu) & MSR_PR)) {
320 		pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
321 		pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
322 		pte->raddr &= KVM_PAM;
323 		pte->may_execute = true;
324 		pte->may_read = true;
325 		pte->may_write = true;
326 
327 		return 0;
328 	}
329 
330 	r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data, iswrite);
331 	if (r < 0)
332 		r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
333 						   data, iswrite, true);
334 	if (r == -ENOENT)
335 		r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
336 						   data, iswrite, false);
337 
338 	return r;
339 }
340 
341 
342 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
343 {
344 	return kvmppc_get_sr(vcpu, srnum);
345 }
346 
347 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
348 					ulong value)
349 {
350 	kvmppc_set_sr(vcpu, srnum, value);
351 	kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
352 }
353 
354 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
355 {
356 	int i;
357 	struct kvm_vcpu *v;
358 
359 	/* flush this VA on all cpus */
360 	kvm_for_each_vcpu(i, v, vcpu->kvm)
361 		kvmppc_mmu_pte_flush(v, ea, 0x0FFFF000);
362 }
363 
364 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
365 					     u64 *vsid)
366 {
367 	ulong ea = esid << SID_SHIFT;
368 	u32 sr;
369 	u64 gvsid = esid;
370 	u64 msr = kvmppc_get_msr(vcpu);
371 
372 	if (msr & (MSR_DR|MSR_IR)) {
373 		sr = find_sr(vcpu, ea);
374 		if (sr_valid(sr))
375 			gvsid = sr_vsid(sr);
376 	}
377 
378 	/* In case we only have one of MSR_IR or MSR_DR set, let's put
379 	   that in the real-mode context (and hope RM doesn't access
380 	   high memory) */
381 	switch (msr & (MSR_DR|MSR_IR)) {
382 	case 0:
383 		*vsid = VSID_REAL | esid;
384 		break;
385 	case MSR_IR:
386 		*vsid = VSID_REAL_IR | gvsid;
387 		break;
388 	case MSR_DR:
389 		*vsid = VSID_REAL_DR | gvsid;
390 		break;
391 	case MSR_DR|MSR_IR:
392 		if (sr_valid(sr))
393 			*vsid = sr_vsid(sr);
394 		else
395 			*vsid = VSID_BAT | gvsid;
396 		break;
397 	default:
398 		BUG();
399 	}
400 
401 	if (msr & MSR_PR)
402 		*vsid |= VSID_PR;
403 
404 	return 0;
405 }
406 
407 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
408 {
409 	return true;
410 }
411 
412 
413 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
414 {
415 	struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
416 
417 	mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
418 	mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
419 	mmu->xlate = kvmppc_mmu_book3s_32_xlate;
420 	mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
421 	mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
422 	mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
423 	mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
424 	mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
425 
426 	mmu->slbmte = NULL;
427 	mmu->slbmfee = NULL;
428 	mmu->slbmfev = NULL;
429 	mmu->slbie = NULL;
430 	mmu->slbia = NULL;
431 }
432