xref: /openbmc/linux/arch/powerpc/kvm/book3s_32_mmu.c (revision 206a81c1)
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 inline bool sr_nx(u32 sr_raw)
82 {
83 	return (sr_raw & 0x10000000) ? true: false;
84 }
85 
86 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
87 					  struct kvmppc_pte *pte, bool data,
88 					  bool iswrite);
89 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
90 					     u64 *vsid);
91 
92 static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
93 {
94 	return kvmppc_get_sr(vcpu, (eaddr >> 28) & 0xf);
95 }
96 
97 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
98 					 bool data)
99 {
100 	u64 vsid;
101 	struct kvmppc_pte pte;
102 
103 	if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data, false))
104 		return pte.vpage;
105 
106 	kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
107 	return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
108 }
109 
110 static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
111 {
112 	kvmppc_set_msr(vcpu, 0);
113 }
114 
115 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvm_vcpu *vcpu,
116 				      u32 sre, gva_t eaddr,
117 				      bool primary)
118 {
119 	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
120 	u32 page, hash, pteg, htabmask;
121 	hva_t r;
122 
123 	page = (eaddr & 0x0FFFFFFF) >> 12;
124 	htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
125 
126 	hash = ((sr_vsid(sre) ^ page) << 6);
127 	if (!primary)
128 		hash = ~hash;
129 	hash &= htabmask;
130 
131 	pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
132 
133 	dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
134 		kvmppc_get_pc(vcpu), eaddr, vcpu_book3s->sdr1, pteg,
135 		sr_vsid(sre));
136 
137 	r = gfn_to_hva(vcpu->kvm, pteg >> PAGE_SHIFT);
138 	if (kvm_is_error_hva(r))
139 		return r;
140 	return r | (pteg & ~PAGE_MASK);
141 }
142 
143 static u32 kvmppc_mmu_book3s_32_get_ptem(u32 sre, gva_t eaddr, bool primary)
144 {
145 	return ((eaddr & 0x0fffffff) >> 22) | (sr_vsid(sre) << 7) |
146 	       (primary ? 0 : 0x40) | 0x80000000;
147 }
148 
149 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
150 					  struct kvmppc_pte *pte, bool data,
151 					  bool iswrite)
152 {
153 	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
154 	struct kvmppc_bat *bat;
155 	int i;
156 
157 	for (i = 0; i < 8; i++) {
158 		if (data)
159 			bat = &vcpu_book3s->dbat[i];
160 		else
161 			bat = &vcpu_book3s->ibat[i];
162 
163 		if (kvmppc_get_msr(vcpu) & MSR_PR) {
164 			if (!bat->vp)
165 				continue;
166 		} else {
167 			if (!bat->vs)
168 				continue;
169 		}
170 
171 		if (check_debug_ip(vcpu))
172 		{
173 			dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
174 				    data ? 'd' : 'i', i, eaddr, bat->bepi,
175 				    bat->bepi_mask);
176 		}
177 		if ((eaddr & bat->bepi_mask) == bat->bepi) {
178 			u64 vsid;
179 			kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
180 				eaddr >> SID_SHIFT, &vsid);
181 			vsid <<= 16;
182 			pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
183 
184 			pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
185 			pte->may_read = bat->pp;
186 			pte->may_write = bat->pp > 1;
187 			pte->may_execute = true;
188 			if (!pte->may_read) {
189 				printk(KERN_INFO "BAT is not readable!\n");
190 				continue;
191 			}
192 			if (iswrite && !pte->may_write) {
193 				dprintk_pte("BAT is read-only!\n");
194 				continue;
195 			}
196 
197 			return 0;
198 		}
199 	}
200 
201 	return -ENOENT;
202 }
203 
204 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
205 				     struct kvmppc_pte *pte, bool data,
206 				     bool iswrite, bool primary)
207 {
208 	u32 sre;
209 	hva_t ptegp;
210 	u32 pteg[16];
211 	u32 pte0, pte1;
212 	u32 ptem = 0;
213 	int i;
214 	int found = 0;
215 
216 	sre = find_sr(vcpu, eaddr);
217 
218 	dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
219 		    sr_vsid(sre), sre);
220 
221 	pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
222 
223 	ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu, sre, eaddr, primary);
224 	if (kvm_is_error_hva(ptegp)) {
225 		printk(KERN_INFO "KVM: Invalid PTEG!\n");
226 		goto no_page_found;
227 	}
228 
229 	ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
230 
231 	if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
232 		printk(KERN_ERR "KVM: Can't copy data from 0x%lx!\n", ptegp);
233 		goto no_page_found;
234 	}
235 
236 	for (i=0; i<16; i+=2) {
237 		pte0 = be32_to_cpu(pteg[i]);
238 		pte1 = be32_to_cpu(pteg[i + 1]);
239 		if (ptem == pte0) {
240 			u8 pp;
241 
242 			pte->raddr = (pte1 & ~(0xFFFULL)) | (eaddr & 0xFFF);
243 			pp = pte1 & 3;
244 
245 			if ((sr_kp(sre) &&  (kvmppc_get_msr(vcpu) & MSR_PR)) ||
246 			    (sr_ks(sre) && !(kvmppc_get_msr(vcpu) & MSR_PR)))
247 				pp |= 4;
248 
249 			pte->may_write = false;
250 			pte->may_read = false;
251 			pte->may_execute = true;
252 			switch (pp) {
253 				case 0:
254 				case 1:
255 				case 2:
256 				case 6:
257 					pte->may_write = true;
258 				case 3:
259 				case 5:
260 				case 7:
261 					pte->may_read = true;
262 					break;
263 			}
264 
265 			dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
266 				    pte0, pte1, pp);
267 			found = 1;
268 			break;
269 		}
270 	}
271 
272 	/* Update PTE C and A bits, so the guest's swapper knows we used the
273 	   page */
274 	if (found) {
275 		u32 pte_r = pte1;
276 		char __user *addr = (char __user *) (ptegp + (i+1) * sizeof(u32));
277 
278 		/*
279 		 * Use single-byte writes to update the HPTE, to
280 		 * conform to what real hardware does.
281 		 */
282 		if (pte->may_read && !(pte_r & PTEG_FLAG_ACCESSED)) {
283 			pte_r |= PTEG_FLAG_ACCESSED;
284 			put_user(pte_r >> 8, addr + 2);
285 		}
286 		if (iswrite && pte->may_write && !(pte_r & PTEG_FLAG_DIRTY)) {
287 			pte_r |= PTEG_FLAG_DIRTY;
288 			put_user(pte_r, addr + 3);
289 		}
290 		if (!pte->may_read || (iswrite && !pte->may_write))
291 			return -EPERM;
292 		return 0;
293 	}
294 
295 no_page_found:
296 
297 	if (check_debug_ip(vcpu)) {
298 		dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
299 			    to_book3s(vcpu)->sdr1, ptegp);
300 		for (i=0; i<16; i+=2) {
301 			dprintk_pte("   %02d: 0x%x - 0x%x (0x%x)\n",
302 				    i, be32_to_cpu(pteg[i]),
303 				    be32_to_cpu(pteg[i+1]), ptem);
304 		}
305 	}
306 
307 	return -ENOENT;
308 }
309 
310 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
311 				      struct kvmppc_pte *pte, bool data,
312 				      bool iswrite)
313 {
314 	int r;
315 	ulong mp_ea = vcpu->arch.magic_page_ea;
316 
317 	pte->eaddr = eaddr;
318 	pte->page_size = MMU_PAGE_4K;
319 
320 	/* Magic page override */
321 	if (unlikely(mp_ea) &&
322 	    unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
323 	    !(kvmppc_get_msr(vcpu) & MSR_PR)) {
324 		pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
325 		pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
326 		pte->raddr &= KVM_PAM;
327 		pte->may_execute = true;
328 		pte->may_read = true;
329 		pte->may_write = true;
330 
331 		return 0;
332 	}
333 
334 	r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data, iswrite);
335 	if (r < 0)
336 		r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
337 						   data, iswrite, true);
338 	if (r < 0)
339 		r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
340 						   data, iswrite, false);
341 
342 	return r;
343 }
344 
345 
346 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
347 {
348 	return kvmppc_get_sr(vcpu, srnum);
349 }
350 
351 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
352 					ulong value)
353 {
354 	kvmppc_set_sr(vcpu, srnum, value);
355 	kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
356 }
357 
358 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
359 {
360 	int i;
361 	struct kvm_vcpu *v;
362 
363 	/* flush this VA on all cpus */
364 	kvm_for_each_vcpu(i, v, vcpu->kvm)
365 		kvmppc_mmu_pte_flush(v, ea, 0x0FFFF000);
366 }
367 
368 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
369 					     u64 *vsid)
370 {
371 	ulong ea = esid << SID_SHIFT;
372 	u32 sr;
373 	u64 gvsid = esid;
374 	u64 msr = kvmppc_get_msr(vcpu);
375 
376 	if (msr & (MSR_DR|MSR_IR)) {
377 		sr = find_sr(vcpu, ea);
378 		if (sr_valid(sr))
379 			gvsid = sr_vsid(sr);
380 	}
381 
382 	/* In case we only have one of MSR_IR or MSR_DR set, let's put
383 	   that in the real-mode context (and hope RM doesn't access
384 	   high memory) */
385 	switch (msr & (MSR_DR|MSR_IR)) {
386 	case 0:
387 		*vsid = VSID_REAL | esid;
388 		break;
389 	case MSR_IR:
390 		*vsid = VSID_REAL_IR | gvsid;
391 		break;
392 	case MSR_DR:
393 		*vsid = VSID_REAL_DR | gvsid;
394 		break;
395 	case MSR_DR|MSR_IR:
396 		if (sr_valid(sr))
397 			*vsid = sr_vsid(sr);
398 		else
399 			*vsid = VSID_BAT | gvsid;
400 		break;
401 	default:
402 		BUG();
403 	}
404 
405 	if (msr & MSR_PR)
406 		*vsid |= VSID_PR;
407 
408 	return 0;
409 }
410 
411 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
412 {
413 	return true;
414 }
415 
416 
417 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
418 {
419 	struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
420 
421 	mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
422 	mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
423 	mmu->xlate = kvmppc_mmu_book3s_32_xlate;
424 	mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
425 	mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
426 	mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
427 	mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
428 	mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
429 
430 	mmu->slbmte = NULL;
431 	mmu->slbmfee = NULL;
432 	mmu->slbmfev = NULL;
433 	mmu->slbie = NULL;
434 	mmu->slbia = NULL;
435 }
436