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Merge remote-tracking branches 'asoc/fix/dpcm', 'asoc/fix/imx', 'asoc/fix/msm8916...
[mirror_ubuntu-artful-kernel.git] / arch / powerpc / kvm / book3s_64_mmu_hv.c
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 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
16 */
17
18 #include <linux/types.h>
19 #include <linux/string.h>
20 #include <linux/kvm.h>
21 #include <linux/kvm_host.h>
22 #include <linux/highmem.h>
23 #include <linux/gfp.h>
24 #include <linux/slab.h>
25 #include <linux/hugetlb.h>
26 #include <linux/vmalloc.h>
27 #include <linux/srcu.h>
28 #include <linux/anon_inodes.h>
29 #include <linux/file.h>
30 #include <linux/debugfs.h>
31
32 #include <asm/tlbflush.h>
33 #include <asm/kvm_ppc.h>
34 #include <asm/kvm_book3s.h>
35 #include <asm/book3s/64/mmu-hash.h>
36 #include <asm/hvcall.h>
37 #include <asm/synch.h>
38 #include <asm/ppc-opcode.h>
39 #include <asm/cputable.h>
40
41 #include "trace_hv.h"
42
43 //#define DEBUG_RESIZE_HPT 1
44
45 #ifdef DEBUG_RESIZE_HPT
46 #define resize_hpt_debug(resize, ...) \
47 do { \
48 printk(KERN_DEBUG "RESIZE HPT %p: ", resize); \
49 printk(__VA_ARGS__); \
50 } while (0)
51 #else
52 #define resize_hpt_debug(resize, ...) \
53 do { } while (0)
54 #endif
55
56 static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
57 long pte_index, unsigned long pteh,
58 unsigned long ptel, unsigned long *pte_idx_ret);
59
60 struct kvm_resize_hpt {
61 /* These fields read-only after init */
62 struct kvm *kvm;
63 struct work_struct work;
64 u32 order;
65
66 /* These fields protected by kvm->lock */
67 int error;
68 bool prepare_done;
69
70 /* Private to the work thread, until prepare_done is true,
71 * then protected by kvm->resize_hpt_sem */
72 struct kvm_hpt_info hpt;
73 };
74
75 static void kvmppc_rmap_reset(struct kvm *kvm);
76
77 int kvmppc_allocate_hpt(struct kvm_hpt_info *info, u32 order)
78 {
79 unsigned long hpt = 0;
80 int cma = 0;
81 struct page *page = NULL;
82 struct revmap_entry *rev;
83 unsigned long npte;
84
85 if ((order < PPC_MIN_HPT_ORDER) || (order > PPC_MAX_HPT_ORDER))
86 return -EINVAL;
87
88 page = kvm_alloc_hpt_cma(1ul << (order - PAGE_SHIFT));
89 if (page) {
90 hpt = (unsigned long)pfn_to_kaddr(page_to_pfn(page));
91 memset((void *)hpt, 0, (1ul << order));
92 cma = 1;
93 }
94
95 if (!hpt)
96 hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL
97 |__GFP_NOWARN, order - PAGE_SHIFT);
98
99 if (!hpt)
100 return -ENOMEM;
101
102 /* HPTEs are 2**4 bytes long */
103 npte = 1ul << (order - 4);
104
105 /* Allocate reverse map array */
106 rev = vmalloc(sizeof(struct revmap_entry) * npte);
107 if (!rev) {
108 pr_err("kvmppc_allocate_hpt: Couldn't alloc reverse map array\n");
109 if (cma)
110 kvm_free_hpt_cma(page, 1 << (order - PAGE_SHIFT));
111 else
112 free_pages(hpt, order - PAGE_SHIFT);
113 return -ENOMEM;
114 }
115
116 info->order = order;
117 info->virt = hpt;
118 info->cma = cma;
119 info->rev = rev;
120
121 return 0;
122 }
123
124 void kvmppc_set_hpt(struct kvm *kvm, struct kvm_hpt_info *info)
125 {
126 atomic64_set(&kvm->arch.mmio_update, 0);
127 kvm->arch.hpt = *info;
128 kvm->arch.sdr1 = __pa(info->virt) | (info->order - 18);
129
130 pr_debug("KVM guest htab at %lx (order %ld), LPID %x\n",
131 info->virt, (long)info->order, kvm->arch.lpid);
132 }
133
134 long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order)
135 {
136 long err = -EBUSY;
137 struct kvm_hpt_info info;
138
139 if (kvm_is_radix(kvm))
140 return -EINVAL;
141
142 mutex_lock(&kvm->lock);
143 if (kvm->arch.hpte_setup_done) {
144 kvm->arch.hpte_setup_done = 0;
145 /* order hpte_setup_done vs. vcpus_running */
146 smp_mb();
147 if (atomic_read(&kvm->arch.vcpus_running)) {
148 kvm->arch.hpte_setup_done = 1;
149 goto out;
150 }
151 }
152 if (kvm->arch.hpt.order == order) {
153 /* We already have a suitable HPT */
154
155 /* Set the entire HPT to 0, i.e. invalid HPTEs */
156 memset((void *)kvm->arch.hpt.virt, 0, 1ul << order);
157 /*
158 * Reset all the reverse-mapping chains for all memslots
159 */
160 kvmppc_rmap_reset(kvm);
161 /* Ensure that each vcpu will flush its TLB on next entry. */
162 cpumask_setall(&kvm->arch.need_tlb_flush);
163 err = 0;
164 goto out;
165 }
166
167 if (kvm->arch.hpt.virt) {
168 kvmppc_free_hpt(&kvm->arch.hpt);
169 kvmppc_rmap_reset(kvm);
170 }
171
172 err = kvmppc_allocate_hpt(&info, order);
173 if (err < 0)
174 goto out;
175 kvmppc_set_hpt(kvm, &info);
176
177 out:
178 mutex_unlock(&kvm->lock);
179 return err;
180 }
181
182 void kvmppc_free_hpt(struct kvm_hpt_info *info)
183 {
184 vfree(info->rev);
185 if (info->cma)
186 kvm_free_hpt_cma(virt_to_page(info->virt),
187 1 << (info->order - PAGE_SHIFT));
188 else if (info->virt)
189 free_pages(info->virt, info->order - PAGE_SHIFT);
190 info->virt = 0;
191 info->order = 0;
192 }
193
194 /* Bits in first HPTE dword for pagesize 4k, 64k or 16M */
195 static inline unsigned long hpte0_pgsize_encoding(unsigned long pgsize)
196 {
197 return (pgsize > 0x1000) ? HPTE_V_LARGE : 0;
198 }
199
200 /* Bits in second HPTE dword for pagesize 4k, 64k or 16M */
201 static inline unsigned long hpte1_pgsize_encoding(unsigned long pgsize)
202 {
203 return (pgsize == 0x10000) ? 0x1000 : 0;
204 }
205
206 void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot,
207 unsigned long porder)
208 {
209 unsigned long i;
210 unsigned long npages;
211 unsigned long hp_v, hp_r;
212 unsigned long addr, hash;
213 unsigned long psize;
214 unsigned long hp0, hp1;
215 unsigned long idx_ret;
216 long ret;
217 struct kvm *kvm = vcpu->kvm;
218
219 psize = 1ul << porder;
220 npages = memslot->npages >> (porder - PAGE_SHIFT);
221
222 /* VRMA can't be > 1TB */
223 if (npages > 1ul << (40 - porder))
224 npages = 1ul << (40 - porder);
225 /* Can't use more than 1 HPTE per HPTEG */
226 if (npages > kvmppc_hpt_mask(&kvm->arch.hpt) + 1)
227 npages = kvmppc_hpt_mask(&kvm->arch.hpt) + 1;
228
229 hp0 = HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)) |
230 HPTE_V_BOLTED | hpte0_pgsize_encoding(psize);
231 hp1 = hpte1_pgsize_encoding(psize) |
232 HPTE_R_R | HPTE_R_C | HPTE_R_M | PP_RWXX;
233
234 for (i = 0; i < npages; ++i) {
235 addr = i << porder;
236 /* can't use hpt_hash since va > 64 bits */
237 hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25)))
238 & kvmppc_hpt_mask(&kvm->arch.hpt);
239 /*
240 * We assume that the hash table is empty and no
241 * vcpus are using it at this stage. Since we create
242 * at most one HPTE per HPTEG, we just assume entry 7
243 * is available and use it.
244 */
245 hash = (hash << 3) + 7;
246 hp_v = hp0 | ((addr >> 16) & ~0x7fUL);
247 hp_r = hp1 | addr;
248 ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, hash, hp_v, hp_r,
249 &idx_ret);
250 if (ret != H_SUCCESS) {
251 pr_err("KVM: map_vrma at %lx failed, ret=%ld\n",
252 addr, ret);
253 break;
254 }
255 }
256 }
257
258 int kvmppc_mmu_hv_init(void)
259 {
260 unsigned long host_lpid, rsvd_lpid;
261
262 if (!cpu_has_feature(CPU_FTR_HVMODE))
263 return -EINVAL;
264
265 /* POWER7 has 10-bit LPIDs (12-bit in POWER8) */
266 host_lpid = mfspr(SPRN_LPID);
267 rsvd_lpid = LPID_RSVD;
268
269 kvmppc_init_lpid(rsvd_lpid + 1);
270
271 kvmppc_claim_lpid(host_lpid);
272 /* rsvd_lpid is reserved for use in partition switching */
273 kvmppc_claim_lpid(rsvd_lpid);
274
275 return 0;
276 }
277
278 static void kvmppc_mmu_book3s_64_hv_reset_msr(struct kvm_vcpu *vcpu)
279 {
280 unsigned long msr = vcpu->arch.intr_msr;
281
282 /* If transactional, change to suspend mode on IRQ delivery */
283 if (MSR_TM_TRANSACTIONAL(vcpu->arch.shregs.msr))
284 msr |= MSR_TS_S;
285 else
286 msr |= vcpu->arch.shregs.msr & MSR_TS_MASK;
287 kvmppc_set_msr(vcpu, msr);
288 }
289
290 static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
291 long pte_index, unsigned long pteh,
292 unsigned long ptel, unsigned long *pte_idx_ret)
293 {
294 long ret;
295
296 /* Protect linux PTE lookup from page table destruction */
297 rcu_read_lock_sched(); /* this disables preemption too */
298 ret = kvmppc_do_h_enter(kvm, flags, pte_index, pteh, ptel,
299 current->mm->pgd, false, pte_idx_ret);
300 rcu_read_unlock_sched();
301 if (ret == H_TOO_HARD) {
302 /* this can't happen */
303 pr_err("KVM: Oops, kvmppc_h_enter returned too hard!\n");
304 ret = H_RESOURCE; /* or something */
305 }
306 return ret;
307
308 }
309
310 static struct kvmppc_slb *kvmppc_mmu_book3s_hv_find_slbe(struct kvm_vcpu *vcpu,
311 gva_t eaddr)
312 {
313 u64 mask;
314 int i;
315
316 for (i = 0; i < vcpu->arch.slb_nr; i++) {
317 if (!(vcpu->arch.slb[i].orige & SLB_ESID_V))
318 continue;
319
320 if (vcpu->arch.slb[i].origv & SLB_VSID_B_1T)
321 mask = ESID_MASK_1T;
322 else
323 mask = ESID_MASK;
324
325 if (((vcpu->arch.slb[i].orige ^ eaddr) & mask) == 0)
326 return &vcpu->arch.slb[i];
327 }
328 return NULL;
329 }
330
331 static unsigned long kvmppc_mmu_get_real_addr(unsigned long v, unsigned long r,
332 unsigned long ea)
333 {
334 unsigned long ra_mask;
335
336 ra_mask = hpte_page_size(v, r) - 1;
337 return (r & HPTE_R_RPN & ~ra_mask) | (ea & ra_mask);
338 }
339
340 static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
341 struct kvmppc_pte *gpte, bool data, bool iswrite)
342 {
343 struct kvm *kvm = vcpu->kvm;
344 struct kvmppc_slb *slbe;
345 unsigned long slb_v;
346 unsigned long pp, key;
347 unsigned long v, orig_v, gr;
348 __be64 *hptep;
349 int index;
350 int virtmode = vcpu->arch.shregs.msr & (data ? MSR_DR : MSR_IR);
351
352 /* Get SLB entry */
353 if (virtmode) {
354 slbe = kvmppc_mmu_book3s_hv_find_slbe(vcpu, eaddr);
355 if (!slbe)
356 return -EINVAL;
357 slb_v = slbe->origv;
358 } else {
359 /* real mode access */
360 slb_v = vcpu->kvm->arch.vrma_slb_v;
361 }
362
363 preempt_disable();
364 /* Find the HPTE in the hash table */
365 index = kvmppc_hv_find_lock_hpte(kvm, eaddr, slb_v,
366 HPTE_V_VALID | HPTE_V_ABSENT);
367 if (index < 0) {
368 preempt_enable();
369 return -ENOENT;
370 }
371 hptep = (__be64 *)(kvm->arch.hpt.virt + (index << 4));
372 v = orig_v = be64_to_cpu(hptep[0]) & ~HPTE_V_HVLOCK;
373 if (cpu_has_feature(CPU_FTR_ARCH_300))
374 v = hpte_new_to_old_v(v, be64_to_cpu(hptep[1]));
375 gr = kvm->arch.hpt.rev[index].guest_rpte;
376
377 unlock_hpte(hptep, orig_v);
378 preempt_enable();
379
380 gpte->eaddr = eaddr;
381 gpte->vpage = ((v & HPTE_V_AVPN) << 4) | ((eaddr >> 12) & 0xfff);
382
383 /* Get PP bits and key for permission check */
384 pp = gr & (HPTE_R_PP0 | HPTE_R_PP);
385 key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;
386 key &= slb_v;
387
388 /* Calculate permissions */
389 gpte->may_read = hpte_read_permission(pp, key);
390 gpte->may_write = hpte_write_permission(pp, key);
391 gpte->may_execute = gpte->may_read && !(gr & (HPTE_R_N | HPTE_R_G));
392
393 /* Storage key permission check for POWER7 */
394 if (data && virtmode) {
395 int amrfield = hpte_get_skey_perm(gr, vcpu->arch.amr);
396 if (amrfield & 1)
397 gpte->may_read = 0;
398 if (amrfield & 2)
399 gpte->may_write = 0;
400 }
401
402 /* Get the guest physical address */
403 gpte->raddr = kvmppc_mmu_get_real_addr(v, gr, eaddr);
404 return 0;
405 }
406
407 /*
408 * Quick test for whether an instruction is a load or a store.
409 * If the instruction is a load or a store, then this will indicate
410 * which it is, at least on server processors. (Embedded processors
411 * have some external PID instructions that don't follow the rule
412 * embodied here.) If the instruction isn't a load or store, then
413 * this doesn't return anything useful.
414 */
415 static int instruction_is_store(unsigned int instr)
416 {
417 unsigned int mask;
418
419 mask = 0x10000000;
420 if ((instr & 0xfc000000) == 0x7c000000)
421 mask = 0x100; /* major opcode 31 */
422 return (instr & mask) != 0;
423 }
424
425 int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu,
426 unsigned long gpa, gva_t ea, int is_store)
427 {
428 u32 last_inst;
429
430 /*
431 * If we fail, we just return to the guest and try executing it again.
432 */
433 if (kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst) !=
434 EMULATE_DONE)
435 return RESUME_GUEST;
436
437 /*
438 * WARNING: We do not know for sure whether the instruction we just
439 * read from memory is the same that caused the fault in the first
440 * place. If the instruction we read is neither an load or a store,
441 * then it can't access memory, so we don't need to worry about
442 * enforcing access permissions. So, assuming it is a load or
443 * store, we just check that its direction (load or store) is
444 * consistent with the original fault, since that's what we
445 * checked the access permissions against. If there is a mismatch
446 * we just return and retry the instruction.
447 */
448
449 if (instruction_is_store(last_inst) != !!is_store)
450 return RESUME_GUEST;
451
452 /*
453 * Emulated accesses are emulated by looking at the hash for
454 * translation once, then performing the access later. The
455 * translation could be invalidated in the meantime in which
456 * point performing the subsequent memory access on the old
457 * physical address could possibly be a security hole for the
458 * guest (but not the host).
459 *
460 * This is less of an issue for MMIO stores since they aren't
461 * globally visible. It could be an issue for MMIO loads to
462 * a certain extent but we'll ignore it for now.
463 */
464
465 vcpu->arch.paddr_accessed = gpa;
466 vcpu->arch.vaddr_accessed = ea;
467 return kvmppc_emulate_mmio(run, vcpu);
468 }
469
470 int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
471 unsigned long ea, unsigned long dsisr)
472 {
473 struct kvm *kvm = vcpu->kvm;
474 unsigned long hpte[3], r;
475 unsigned long hnow_v, hnow_r;
476 __be64 *hptep;
477 unsigned long mmu_seq, psize, pte_size;
478 unsigned long gpa_base, gfn_base;
479 unsigned long gpa, gfn, hva, pfn;
480 struct kvm_memory_slot *memslot;
481 unsigned long *rmap;
482 struct revmap_entry *rev;
483 struct page *page, *pages[1];
484 long index, ret, npages;
485 bool is_ci;
486 unsigned int writing, write_ok;
487 struct vm_area_struct *vma;
488 unsigned long rcbits;
489 long mmio_update;
490
491 if (kvm_is_radix(kvm))
492 return kvmppc_book3s_radix_page_fault(run, vcpu, ea, dsisr);
493
494 /*
495 * Real-mode code has already searched the HPT and found the
496 * entry we're interested in. Lock the entry and check that
497 * it hasn't changed. If it has, just return and re-execute the
498 * instruction.
499 */
500 if (ea != vcpu->arch.pgfault_addr)
501 return RESUME_GUEST;
502
503 if (vcpu->arch.pgfault_cache) {
504 mmio_update = atomic64_read(&kvm->arch.mmio_update);
505 if (mmio_update == vcpu->arch.pgfault_cache->mmio_update) {
506 r = vcpu->arch.pgfault_cache->rpte;
507 psize = hpte_page_size(vcpu->arch.pgfault_hpte[0], r);
508 gpa_base = r & HPTE_R_RPN & ~(psize - 1);
509 gfn_base = gpa_base >> PAGE_SHIFT;
510 gpa = gpa_base | (ea & (psize - 1));
511 return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
512 dsisr & DSISR_ISSTORE);
513 }
514 }
515 index = vcpu->arch.pgfault_index;
516 hptep = (__be64 *)(kvm->arch.hpt.virt + (index << 4));
517 rev = &kvm->arch.hpt.rev[index];
518 preempt_disable();
519 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
520 cpu_relax();
521 hpte[0] = be64_to_cpu(hptep[0]) & ~HPTE_V_HVLOCK;
522 hpte[1] = be64_to_cpu(hptep[1]);
523 hpte[2] = r = rev->guest_rpte;
524 unlock_hpte(hptep, hpte[0]);
525 preempt_enable();
526
527 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
528 hpte[0] = hpte_new_to_old_v(hpte[0], hpte[1]);
529 hpte[1] = hpte_new_to_old_r(hpte[1]);
530 }
531 if (hpte[0] != vcpu->arch.pgfault_hpte[0] ||
532 hpte[1] != vcpu->arch.pgfault_hpte[1])
533 return RESUME_GUEST;
534
535 /* Translate the logical address and get the page */
536 psize = hpte_page_size(hpte[0], r);
537 gpa_base = r & HPTE_R_RPN & ~(psize - 1);
538 gfn_base = gpa_base >> PAGE_SHIFT;
539 gpa = gpa_base | (ea & (psize - 1));
540 gfn = gpa >> PAGE_SHIFT;
541 memslot = gfn_to_memslot(kvm, gfn);
542
543 trace_kvm_page_fault_enter(vcpu, hpte, memslot, ea, dsisr);
544
545 /* No memslot means it's an emulated MMIO region */
546 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
547 return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
548 dsisr & DSISR_ISSTORE);
549
550 /*
551 * This should never happen, because of the slot_is_aligned()
552 * check in kvmppc_do_h_enter().
553 */
554 if (gfn_base < memslot->base_gfn)
555 return -EFAULT;
556
557 /* used to check for invalidations in progress */
558 mmu_seq = kvm->mmu_notifier_seq;
559 smp_rmb();
560
561 ret = -EFAULT;
562 is_ci = false;
563 pfn = 0;
564 page = NULL;
565 pte_size = PAGE_SIZE;
566 writing = (dsisr & DSISR_ISSTORE) != 0;
567 /* If writing != 0, then the HPTE must allow writing, if we get here */
568 write_ok = writing;
569 hva = gfn_to_hva_memslot(memslot, gfn);
570 npages = get_user_pages_fast(hva, 1, writing, pages);
571 if (npages < 1) {
572 /* Check if it's an I/O mapping */
573 down_read(&current->mm->mmap_sem);
574 vma = find_vma(current->mm, hva);
575 if (vma && vma->vm_start <= hva && hva + psize <= vma->vm_end &&
576 (vma->vm_flags & VM_PFNMAP)) {
577 pfn = vma->vm_pgoff +
578 ((hva - vma->vm_start) >> PAGE_SHIFT);
579 pte_size = psize;
580 is_ci = pte_ci(__pte((pgprot_val(vma->vm_page_prot))));
581 write_ok = vma->vm_flags & VM_WRITE;
582 }
583 up_read(&current->mm->mmap_sem);
584 if (!pfn)
585 goto out_put;
586 } else {
587 page = pages[0];
588 pfn = page_to_pfn(page);
589 if (PageHuge(page)) {
590 page = compound_head(page);
591 pte_size <<= compound_order(page);
592 }
593 /* if the guest wants write access, see if that is OK */
594 if (!writing && hpte_is_writable(r)) {
595 pte_t *ptep, pte;
596 unsigned long flags;
597 /*
598 * We need to protect against page table destruction
599 * hugepage split and collapse.
600 */
601 local_irq_save(flags);
602 ptep = find_linux_pte_or_hugepte(current->mm->pgd,
603 hva, NULL, NULL);
604 if (ptep) {
605 pte = kvmppc_read_update_linux_pte(ptep, 1);
606 if (__pte_write(pte))
607 write_ok = 1;
608 }
609 local_irq_restore(flags);
610 }
611 }
612
613 if (psize > pte_size)
614 goto out_put;
615
616 /* Check WIMG vs. the actual page we're accessing */
617 if (!hpte_cache_flags_ok(r, is_ci)) {
618 if (is_ci)
619 goto out_put;
620 /*
621 * Allow guest to map emulated device memory as
622 * uncacheable, but actually make it cacheable.
623 */
624 r = (r & ~(HPTE_R_W|HPTE_R_I|HPTE_R_G)) | HPTE_R_M;
625 }
626
627 /*
628 * Set the HPTE to point to pfn.
629 * Since the pfn is at PAGE_SIZE granularity, make sure we
630 * don't mask out lower-order bits if psize < PAGE_SIZE.
631 */
632 if (psize < PAGE_SIZE)
633 psize = PAGE_SIZE;
634 r = (r & HPTE_R_KEY_HI) | (r & ~(HPTE_R_PP0 - psize)) |
635 ((pfn << PAGE_SHIFT) & ~(psize - 1));
636 if (hpte_is_writable(r) && !write_ok)
637 r = hpte_make_readonly(r);
638 ret = RESUME_GUEST;
639 preempt_disable();
640 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
641 cpu_relax();
642 hnow_v = be64_to_cpu(hptep[0]);
643 hnow_r = be64_to_cpu(hptep[1]);
644 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
645 hnow_v = hpte_new_to_old_v(hnow_v, hnow_r);
646 hnow_r = hpte_new_to_old_r(hnow_r);
647 }
648 if ((hnow_v & ~HPTE_V_HVLOCK) != hpte[0] || hnow_r != hpte[1] ||
649 rev->guest_rpte != hpte[2])
650 /* HPTE has been changed under us; let the guest retry */
651 goto out_unlock;
652 hpte[0] = (hpte[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID;
653
654 /* Always put the HPTE in the rmap chain for the page base address */
655 rmap = &memslot->arch.rmap[gfn_base - memslot->base_gfn];
656 lock_rmap(rmap);
657
658 /* Check if we might have been invalidated; let the guest retry if so */
659 ret = RESUME_GUEST;
660 if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) {
661 unlock_rmap(rmap);
662 goto out_unlock;
663 }
664
665 /* Only set R/C in real HPTE if set in both *rmap and guest_rpte */
666 rcbits = *rmap >> KVMPPC_RMAP_RC_SHIFT;
667 r &= rcbits | ~(HPTE_R_R | HPTE_R_C);
668
669 if (be64_to_cpu(hptep[0]) & HPTE_V_VALID) {
670 /* HPTE was previously valid, so we need to invalidate it */
671 unlock_rmap(rmap);
672 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
673 kvmppc_invalidate_hpte(kvm, hptep, index);
674 /* don't lose previous R and C bits */
675 r |= be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C);
676 } else {
677 kvmppc_add_revmap_chain(kvm, rev, rmap, index, 0);
678 }
679
680 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
681 r = hpte_old_to_new_r(hpte[0], r);
682 hpte[0] = hpte_old_to_new_v(hpte[0]);
683 }
684 hptep[1] = cpu_to_be64(r);
685 eieio();
686 __unlock_hpte(hptep, hpte[0]);
687 asm volatile("ptesync" : : : "memory");
688 preempt_enable();
689 if (page && hpte_is_writable(r))
690 SetPageDirty(page);
691
692 out_put:
693 trace_kvm_page_fault_exit(vcpu, hpte, ret);
694
695 if (page) {
696 /*
697 * We drop pages[0] here, not page because page might
698 * have been set to the head page of a compound, but
699 * we have to drop the reference on the correct tail
700 * page to match the get inside gup()
701 */
702 put_page(pages[0]);
703 }
704 return ret;
705
706 out_unlock:
707 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
708 preempt_enable();
709 goto out_put;
710 }
711
712 static void kvmppc_rmap_reset(struct kvm *kvm)
713 {
714 struct kvm_memslots *slots;
715 struct kvm_memory_slot *memslot;
716 int srcu_idx;
717
718 srcu_idx = srcu_read_lock(&kvm->srcu);
719 slots = kvm_memslots(kvm);
720 kvm_for_each_memslot(memslot, slots) {
721 /*
722 * This assumes it is acceptable to lose reference and
723 * change bits across a reset.
724 */
725 memset(memslot->arch.rmap, 0,
726 memslot->npages * sizeof(*memslot->arch.rmap));
727 }
728 srcu_read_unlock(&kvm->srcu, srcu_idx);
729 }
730
731 typedef int (*hva_handler_fn)(struct kvm *kvm, struct kvm_memory_slot *memslot,
732 unsigned long gfn);
733
734 static int kvm_handle_hva_range(struct kvm *kvm,
735 unsigned long start,
736 unsigned long end,
737 hva_handler_fn handler)
738 {
739 int ret;
740 int retval = 0;
741 struct kvm_memslots *slots;
742 struct kvm_memory_slot *memslot;
743
744 slots = kvm_memslots(kvm);
745 kvm_for_each_memslot(memslot, slots) {
746 unsigned long hva_start, hva_end;
747 gfn_t gfn, gfn_end;
748
749 hva_start = max(start, memslot->userspace_addr);
750 hva_end = min(end, memslot->userspace_addr +
751 (memslot->npages << PAGE_SHIFT));
752 if (hva_start >= hva_end)
753 continue;
754 /*
755 * {gfn(page) | page intersects with [hva_start, hva_end)} =
756 * {gfn, gfn+1, ..., gfn_end-1}.
757 */
758 gfn = hva_to_gfn_memslot(hva_start, memslot);
759 gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);
760
761 for (; gfn < gfn_end; ++gfn) {
762 ret = handler(kvm, memslot, gfn);
763 retval |= ret;
764 }
765 }
766
767 return retval;
768 }
769
770 static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
771 hva_handler_fn handler)
772 {
773 return kvm_handle_hva_range(kvm, hva, hva + 1, handler);
774 }
775
776 /* Must be called with both HPTE and rmap locked */
777 static void kvmppc_unmap_hpte(struct kvm *kvm, unsigned long i,
778 unsigned long *rmapp, unsigned long gfn)
779 {
780 __be64 *hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
781 struct revmap_entry *rev = kvm->arch.hpt.rev;
782 unsigned long j, h;
783 unsigned long ptel, psize, rcbits;
784
785 j = rev[i].forw;
786 if (j == i) {
787 /* chain is now empty */
788 *rmapp &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX);
789 } else {
790 /* remove i from chain */
791 h = rev[i].back;
792 rev[h].forw = j;
793 rev[j].back = h;
794 rev[i].forw = rev[i].back = i;
795 *rmapp = (*rmapp & ~KVMPPC_RMAP_INDEX) | j;
796 }
797
798 /* Now check and modify the HPTE */
799 ptel = rev[i].guest_rpte;
800 psize = hpte_page_size(be64_to_cpu(hptep[0]), ptel);
801 if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) &&
802 hpte_rpn(ptel, psize) == gfn) {
803 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
804 kvmppc_invalidate_hpte(kvm, hptep, i);
805 hptep[1] &= ~cpu_to_be64(HPTE_R_KEY_HI | HPTE_R_KEY_LO);
806 /* Harvest R and C */
807 rcbits = be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C);
808 *rmapp |= rcbits << KVMPPC_RMAP_RC_SHIFT;
809 if (rcbits & HPTE_R_C)
810 kvmppc_update_rmap_change(rmapp, psize);
811 if (rcbits & ~rev[i].guest_rpte) {
812 rev[i].guest_rpte = ptel | rcbits;
813 note_hpte_modification(kvm, &rev[i]);
814 }
815 }
816 }
817
818 static int kvm_unmap_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
819 unsigned long gfn)
820 {
821 unsigned long i;
822 __be64 *hptep;
823 unsigned long *rmapp;
824
825 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
826 for (;;) {
827 lock_rmap(rmapp);
828 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
829 unlock_rmap(rmapp);
830 break;
831 }
832
833 /*
834 * To avoid an ABBA deadlock with the HPTE lock bit,
835 * we can't spin on the HPTE lock while holding the
836 * rmap chain lock.
837 */
838 i = *rmapp & KVMPPC_RMAP_INDEX;
839 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
840 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
841 /* unlock rmap before spinning on the HPTE lock */
842 unlock_rmap(rmapp);
843 while (be64_to_cpu(hptep[0]) & HPTE_V_HVLOCK)
844 cpu_relax();
845 continue;
846 }
847
848 kvmppc_unmap_hpte(kvm, i, rmapp, gfn);
849 unlock_rmap(rmapp);
850 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
851 }
852 return 0;
853 }
854
855 int kvm_unmap_hva_hv(struct kvm *kvm, unsigned long hva)
856 {
857 hva_handler_fn handler;
858
859 handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
860 kvm_handle_hva(kvm, hva, handler);
861 return 0;
862 }
863
864 int kvm_unmap_hva_range_hv(struct kvm *kvm, unsigned long start, unsigned long end)
865 {
866 hva_handler_fn handler;
867
868 handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
869 kvm_handle_hva_range(kvm, start, end, handler);
870 return 0;
871 }
872
873 void kvmppc_core_flush_memslot_hv(struct kvm *kvm,
874 struct kvm_memory_slot *memslot)
875 {
876 unsigned long gfn;
877 unsigned long n;
878 unsigned long *rmapp;
879
880 gfn = memslot->base_gfn;
881 rmapp = memslot->arch.rmap;
882 for (n = memslot->npages; n; --n, ++gfn) {
883 if (kvm_is_radix(kvm)) {
884 kvm_unmap_radix(kvm, memslot, gfn);
885 continue;
886 }
887 /*
888 * Testing the present bit without locking is OK because
889 * the memslot has been marked invalid already, and hence
890 * no new HPTEs referencing this page can be created,
891 * thus the present bit can't go from 0 to 1.
892 */
893 if (*rmapp & KVMPPC_RMAP_PRESENT)
894 kvm_unmap_rmapp(kvm, memslot, gfn);
895 ++rmapp;
896 }
897 }
898
899 static int kvm_age_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
900 unsigned long gfn)
901 {
902 struct revmap_entry *rev = kvm->arch.hpt.rev;
903 unsigned long head, i, j;
904 __be64 *hptep;
905 int ret = 0;
906 unsigned long *rmapp;
907
908 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
909 retry:
910 lock_rmap(rmapp);
911 if (*rmapp & KVMPPC_RMAP_REFERENCED) {
912 *rmapp &= ~KVMPPC_RMAP_REFERENCED;
913 ret = 1;
914 }
915 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
916 unlock_rmap(rmapp);
917 return ret;
918 }
919
920 i = head = *rmapp & KVMPPC_RMAP_INDEX;
921 do {
922 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
923 j = rev[i].forw;
924
925 /* If this HPTE isn't referenced, ignore it */
926 if (!(be64_to_cpu(hptep[1]) & HPTE_R_R))
927 continue;
928
929 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
930 /* unlock rmap before spinning on the HPTE lock */
931 unlock_rmap(rmapp);
932 while (be64_to_cpu(hptep[0]) & HPTE_V_HVLOCK)
933 cpu_relax();
934 goto retry;
935 }
936
937 /* Now check and modify the HPTE */
938 if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) &&
939 (be64_to_cpu(hptep[1]) & HPTE_R_R)) {
940 kvmppc_clear_ref_hpte(kvm, hptep, i);
941 if (!(rev[i].guest_rpte & HPTE_R_R)) {
942 rev[i].guest_rpte |= HPTE_R_R;
943 note_hpte_modification(kvm, &rev[i]);
944 }
945 ret = 1;
946 }
947 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
948 } while ((i = j) != head);
949
950 unlock_rmap(rmapp);
951 return ret;
952 }
953
954 int kvm_age_hva_hv(struct kvm *kvm, unsigned long start, unsigned long end)
955 {
956 hva_handler_fn handler;
957
958 handler = kvm_is_radix(kvm) ? kvm_age_radix : kvm_age_rmapp;
959 return kvm_handle_hva_range(kvm, start, end, handler);
960 }
961
962 static int kvm_test_age_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
963 unsigned long gfn)
964 {
965 struct revmap_entry *rev = kvm->arch.hpt.rev;
966 unsigned long head, i, j;
967 unsigned long *hp;
968 int ret = 1;
969 unsigned long *rmapp;
970
971 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
972 if (*rmapp & KVMPPC_RMAP_REFERENCED)
973 return 1;
974
975 lock_rmap(rmapp);
976 if (*rmapp & KVMPPC_RMAP_REFERENCED)
977 goto out;
978
979 if (*rmapp & KVMPPC_RMAP_PRESENT) {
980 i = head = *rmapp & KVMPPC_RMAP_INDEX;
981 do {
982 hp = (unsigned long *)(kvm->arch.hpt.virt + (i << 4));
983 j = rev[i].forw;
984 if (be64_to_cpu(hp[1]) & HPTE_R_R)
985 goto out;
986 } while ((i = j) != head);
987 }
988 ret = 0;
989
990 out:
991 unlock_rmap(rmapp);
992 return ret;
993 }
994
995 int kvm_test_age_hva_hv(struct kvm *kvm, unsigned long hva)
996 {
997 hva_handler_fn handler;
998
999 handler = kvm_is_radix(kvm) ? kvm_test_age_radix : kvm_test_age_rmapp;
1000 return kvm_handle_hva(kvm, hva, handler);
1001 }
1002
1003 void kvm_set_spte_hva_hv(struct kvm *kvm, unsigned long hva, pte_t pte)
1004 {
1005 hva_handler_fn handler;
1006
1007 handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
1008 kvm_handle_hva(kvm, hva, handler);
1009 }
1010
1011 static int vcpus_running(struct kvm *kvm)
1012 {
1013 return atomic_read(&kvm->arch.vcpus_running) != 0;
1014 }
1015
1016 /*
1017 * Returns the number of system pages that are dirty.
1018 * This can be more than 1 if we find a huge-page HPTE.
1019 */
1020 static int kvm_test_clear_dirty_npages(struct kvm *kvm, unsigned long *rmapp)
1021 {
1022 struct revmap_entry *rev = kvm->arch.hpt.rev;
1023 unsigned long head, i, j;
1024 unsigned long n;
1025 unsigned long v, r;
1026 __be64 *hptep;
1027 int npages_dirty = 0;
1028
1029 retry:
1030 lock_rmap(rmapp);
1031 if (*rmapp & KVMPPC_RMAP_CHANGED) {
1032 long change_order = (*rmapp & KVMPPC_RMAP_CHG_ORDER)
1033 >> KVMPPC_RMAP_CHG_SHIFT;
1034 *rmapp &= ~(KVMPPC_RMAP_CHANGED | KVMPPC_RMAP_CHG_ORDER);
1035 npages_dirty = 1;
1036 if (change_order > PAGE_SHIFT)
1037 npages_dirty = 1ul << (change_order - PAGE_SHIFT);
1038 }
1039 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
1040 unlock_rmap(rmapp);
1041 return npages_dirty;
1042 }
1043
1044 i = head = *rmapp & KVMPPC_RMAP_INDEX;
1045 do {
1046 unsigned long hptep1;
1047 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
1048 j = rev[i].forw;
1049
1050 /*
1051 * Checking the C (changed) bit here is racy since there
1052 * is no guarantee about when the hardware writes it back.
1053 * If the HPTE is not writable then it is stable since the
1054 * page can't be written to, and we would have done a tlbie
1055 * (which forces the hardware to complete any writeback)
1056 * when making the HPTE read-only.
1057 * If vcpus are running then this call is racy anyway
1058 * since the page could get dirtied subsequently, so we
1059 * expect there to be a further call which would pick up
1060 * any delayed C bit writeback.
1061 * Otherwise we need to do the tlbie even if C==0 in
1062 * order to pick up any delayed writeback of C.
1063 */
1064 hptep1 = be64_to_cpu(hptep[1]);
1065 if (!(hptep1 & HPTE_R_C) &&
1066 (!hpte_is_writable(hptep1) || vcpus_running(kvm)))
1067 continue;
1068
1069 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
1070 /* unlock rmap before spinning on the HPTE lock */
1071 unlock_rmap(rmapp);
1072 while (hptep[0] & cpu_to_be64(HPTE_V_HVLOCK))
1073 cpu_relax();
1074 goto retry;
1075 }
1076
1077 /* Now check and modify the HPTE */
1078 if (!(hptep[0] & cpu_to_be64(HPTE_V_VALID))) {
1079 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
1080 continue;
1081 }
1082
1083 /* need to make it temporarily absent so C is stable */
1084 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
1085 kvmppc_invalidate_hpte(kvm, hptep, i);
1086 v = be64_to_cpu(hptep[0]);
1087 r = be64_to_cpu(hptep[1]);
1088 if (r & HPTE_R_C) {
1089 hptep[1] = cpu_to_be64(r & ~HPTE_R_C);
1090 if (!(rev[i].guest_rpte & HPTE_R_C)) {
1091 rev[i].guest_rpte |= HPTE_R_C;
1092 note_hpte_modification(kvm, &rev[i]);
1093 }
1094 n = hpte_page_size(v, r);
1095 n = (n + PAGE_SIZE - 1) >> PAGE_SHIFT;
1096 if (n > npages_dirty)
1097 npages_dirty = n;
1098 eieio();
1099 }
1100 v &= ~HPTE_V_ABSENT;
1101 v |= HPTE_V_VALID;
1102 __unlock_hpte(hptep, v);
1103 } while ((i = j) != head);
1104
1105 unlock_rmap(rmapp);
1106 return npages_dirty;
1107 }
1108
1109 void kvmppc_harvest_vpa_dirty(struct kvmppc_vpa *vpa,
1110 struct kvm_memory_slot *memslot,
1111 unsigned long *map)
1112 {
1113 unsigned long gfn;
1114
1115 if (!vpa->dirty || !vpa->pinned_addr)
1116 return;
1117 gfn = vpa->gpa >> PAGE_SHIFT;
1118 if (gfn < memslot->base_gfn ||
1119 gfn >= memslot->base_gfn + memslot->npages)
1120 return;
1121
1122 vpa->dirty = false;
1123 if (map)
1124 __set_bit_le(gfn - memslot->base_gfn, map);
1125 }
1126
1127 long kvmppc_hv_get_dirty_log_hpt(struct kvm *kvm,
1128 struct kvm_memory_slot *memslot, unsigned long *map)
1129 {
1130 unsigned long i, j;
1131 unsigned long *rmapp;
1132
1133 preempt_disable();
1134 rmapp = memslot->arch.rmap;
1135 for (i = 0; i < memslot->npages; ++i) {
1136 int npages = kvm_test_clear_dirty_npages(kvm, rmapp);
1137 /*
1138 * Note that if npages > 0 then i must be a multiple of npages,
1139 * since we always put huge-page HPTEs in the rmap chain
1140 * corresponding to their page base address.
1141 */
1142 if (npages && map)
1143 for (j = i; npages; ++j, --npages)
1144 __set_bit_le(j, map);
1145 ++rmapp;
1146 }
1147 preempt_enable();
1148 return 0;
1149 }
1150
1151 void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
1152 unsigned long *nb_ret)
1153 {
1154 struct kvm_memory_slot *memslot;
1155 unsigned long gfn = gpa >> PAGE_SHIFT;
1156 struct page *page, *pages[1];
1157 int npages;
1158 unsigned long hva, offset;
1159 int srcu_idx;
1160
1161 srcu_idx = srcu_read_lock(&kvm->srcu);
1162 memslot = gfn_to_memslot(kvm, gfn);
1163 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
1164 goto err;
1165 hva = gfn_to_hva_memslot(memslot, gfn);
1166 npages = get_user_pages_fast(hva, 1, 1, pages);
1167 if (npages < 1)
1168 goto err;
1169 page = pages[0];
1170 srcu_read_unlock(&kvm->srcu, srcu_idx);
1171
1172 offset = gpa & (PAGE_SIZE - 1);
1173 if (nb_ret)
1174 *nb_ret = PAGE_SIZE - offset;
1175 return page_address(page) + offset;
1176
1177 err:
1178 srcu_read_unlock(&kvm->srcu, srcu_idx);
1179 return NULL;
1180 }
1181
1182 void kvmppc_unpin_guest_page(struct kvm *kvm, void *va, unsigned long gpa,
1183 bool dirty)
1184 {
1185 struct page *page = virt_to_page(va);
1186 struct kvm_memory_slot *memslot;
1187 unsigned long gfn;
1188 unsigned long *rmap;
1189 int srcu_idx;
1190
1191 put_page(page);
1192
1193 if (!dirty)
1194 return;
1195
1196 /* We need to mark this page dirty in the rmap chain */
1197 gfn = gpa >> PAGE_SHIFT;
1198 srcu_idx = srcu_read_lock(&kvm->srcu);
1199 memslot = gfn_to_memslot(kvm, gfn);
1200 if (memslot) {
1201 if (!kvm_is_radix(kvm)) {
1202 rmap = &memslot->arch.rmap[gfn - memslot->base_gfn];
1203 lock_rmap(rmap);
1204 *rmap |= KVMPPC_RMAP_CHANGED;
1205 unlock_rmap(rmap);
1206 } else if (memslot->dirty_bitmap) {
1207 mark_page_dirty(kvm, gfn);
1208 }
1209 }
1210 srcu_read_unlock(&kvm->srcu, srcu_idx);
1211 }
1212
1213 /*
1214 * HPT resizing
1215 */
1216 static int resize_hpt_allocate(struct kvm_resize_hpt *resize)
1217 {
1218 int rc;
1219
1220 rc = kvmppc_allocate_hpt(&resize->hpt, resize->order);
1221 if (rc < 0)
1222 return rc;
1223
1224 resize_hpt_debug(resize, "resize_hpt_allocate(): HPT @ 0x%lx\n",
1225 resize->hpt.virt);
1226
1227 return 0;
1228 }
1229
1230 static unsigned long resize_hpt_rehash_hpte(struct kvm_resize_hpt *resize,
1231 unsigned long idx)
1232 {
1233 struct kvm *kvm = resize->kvm;
1234 struct kvm_hpt_info *old = &kvm->arch.hpt;
1235 struct kvm_hpt_info *new = &resize->hpt;
1236 unsigned long old_hash_mask = (1ULL << (old->order - 7)) - 1;
1237 unsigned long new_hash_mask = (1ULL << (new->order - 7)) - 1;
1238 __be64 *hptep, *new_hptep;
1239 unsigned long vpte, rpte, guest_rpte;
1240 int ret;
1241 struct revmap_entry *rev;
1242 unsigned long apsize, psize, avpn, pteg, hash;
1243 unsigned long new_idx, new_pteg, replace_vpte;
1244
1245 hptep = (__be64 *)(old->virt + (idx << 4));
1246
1247 /* Guest is stopped, so new HPTEs can't be added or faulted
1248 * in, only unmapped or altered by host actions. So, it's
1249 * safe to check this before we take the HPTE lock */
1250 vpte = be64_to_cpu(hptep[0]);
1251 if (!(vpte & HPTE_V_VALID) && !(vpte & HPTE_V_ABSENT))
1252 return 0; /* nothing to do */
1253
1254 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
1255 cpu_relax();
1256
1257 vpte = be64_to_cpu(hptep[0]);
1258
1259 ret = 0;
1260 if (!(vpte & HPTE_V_VALID) && !(vpte & HPTE_V_ABSENT))
1261 /* Nothing to do */
1262 goto out;
1263
1264 /* Unmap */
1265 rev = &old->rev[idx];
1266 guest_rpte = rev->guest_rpte;
1267
1268 ret = -EIO;
1269 apsize = hpte_page_size(vpte, guest_rpte);
1270 if (!apsize)
1271 goto out;
1272
1273 if (vpte & HPTE_V_VALID) {
1274 unsigned long gfn = hpte_rpn(guest_rpte, apsize);
1275 int srcu_idx = srcu_read_lock(&kvm->srcu);
1276 struct kvm_memory_slot *memslot =
1277 __gfn_to_memslot(kvm_memslots(kvm), gfn);
1278
1279 if (memslot) {
1280 unsigned long *rmapp;
1281 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1282
1283 lock_rmap(rmapp);
1284 kvmppc_unmap_hpte(kvm, idx, rmapp, gfn);
1285 unlock_rmap(rmapp);
1286 }
1287
1288 srcu_read_unlock(&kvm->srcu, srcu_idx);
1289 }
1290
1291 /* Reload PTE after unmap */
1292 vpte = be64_to_cpu(hptep[0]);
1293
1294 BUG_ON(vpte & HPTE_V_VALID);
1295 BUG_ON(!(vpte & HPTE_V_ABSENT));
1296
1297 ret = 0;
1298 if (!(vpte & HPTE_V_BOLTED))
1299 goto out;
1300
1301 rpte = be64_to_cpu(hptep[1]);
1302 psize = hpte_base_page_size(vpte, rpte);
1303 avpn = HPTE_V_AVPN_VAL(vpte) & ~((psize - 1) >> 23);
1304 pteg = idx / HPTES_PER_GROUP;
1305 if (vpte & HPTE_V_SECONDARY)
1306 pteg = ~pteg;
1307
1308 if (!(vpte & HPTE_V_1TB_SEG)) {
1309 unsigned long offset, vsid;
1310
1311 /* We only have 28 - 23 bits of offset in avpn */
1312 offset = (avpn & 0x1f) << 23;
1313 vsid = avpn >> 5;
1314 /* We can find more bits from the pteg value */
1315 if (psize < (1ULL << 23))
1316 offset |= ((vsid ^ pteg) & old_hash_mask) * psize;
1317
1318 hash = vsid ^ (offset / psize);
1319 } else {
1320 unsigned long offset, vsid;
1321
1322 /* We only have 40 - 23 bits of seg_off in avpn */
1323 offset = (avpn & 0x1ffff) << 23;
1324 vsid = avpn >> 17;
1325 if (psize < (1ULL << 23))
1326 offset |= ((vsid ^ (vsid << 25) ^ pteg) & old_hash_mask) * psize;
1327
1328 hash = vsid ^ (vsid << 25) ^ (offset / psize);
1329 }
1330
1331 new_pteg = hash & new_hash_mask;
1332 if (vpte & HPTE_V_SECONDARY) {
1333 BUG_ON(~pteg != (hash & old_hash_mask));
1334 new_pteg = ~new_pteg;
1335 } else {
1336 BUG_ON(pteg != (hash & old_hash_mask));
1337 }
1338
1339 new_idx = new_pteg * HPTES_PER_GROUP + (idx % HPTES_PER_GROUP);
1340 new_hptep = (__be64 *)(new->virt + (new_idx << 4));
1341
1342 replace_vpte = be64_to_cpu(new_hptep[0]);
1343
1344 if (replace_vpte & (HPTE_V_VALID | HPTE_V_ABSENT)) {
1345 BUG_ON(new->order >= old->order);
1346
1347 if (replace_vpte & HPTE_V_BOLTED) {
1348 if (vpte & HPTE_V_BOLTED)
1349 /* Bolted collision, nothing we can do */
1350 ret = -ENOSPC;
1351 /* Discard the new HPTE */
1352 goto out;
1353 }
1354
1355 /* Discard the previous HPTE */
1356 }
1357
1358 new_hptep[1] = cpu_to_be64(rpte);
1359 new->rev[new_idx].guest_rpte = guest_rpte;
1360 /* No need for a barrier, since new HPT isn't active */
1361 new_hptep[0] = cpu_to_be64(vpte);
1362 unlock_hpte(new_hptep, vpte);
1363
1364 out:
1365 unlock_hpte(hptep, vpte);
1366 return ret;
1367 }
1368
1369 static int resize_hpt_rehash(struct kvm_resize_hpt *resize)
1370 {
1371 struct kvm *kvm = resize->kvm;
1372 unsigned long i;
1373 int rc;
1374
1375 /*
1376 * resize_hpt_rehash_hpte() doesn't handle the new-format HPTEs
1377 * that POWER9 uses, and could well hit a BUG_ON on POWER9.
1378 */
1379 if (cpu_has_feature(CPU_FTR_ARCH_300))
1380 return -EIO;
1381 for (i = 0; i < kvmppc_hpt_npte(&kvm->arch.hpt); i++) {
1382 rc = resize_hpt_rehash_hpte(resize, i);
1383 if (rc != 0)
1384 return rc;
1385 }
1386
1387 return 0;
1388 }
1389
1390 static void resize_hpt_pivot(struct kvm_resize_hpt *resize)
1391 {
1392 struct kvm *kvm = resize->kvm;
1393 struct kvm_hpt_info hpt_tmp;
1394
1395 /* Exchange the pending tables in the resize structure with
1396 * the active tables */
1397
1398 resize_hpt_debug(resize, "resize_hpt_pivot()\n");
1399
1400 spin_lock(&kvm->mmu_lock);
1401 asm volatile("ptesync" : : : "memory");
1402
1403 hpt_tmp = kvm->arch.hpt;
1404 kvmppc_set_hpt(kvm, &resize->hpt);
1405 resize->hpt = hpt_tmp;
1406
1407 spin_unlock(&kvm->mmu_lock);
1408
1409 synchronize_srcu_expedited(&kvm->srcu);
1410
1411 resize_hpt_debug(resize, "resize_hpt_pivot() done\n");
1412 }
1413
1414 static void resize_hpt_release(struct kvm *kvm, struct kvm_resize_hpt *resize)
1415 {
1416 BUG_ON(kvm->arch.resize_hpt != resize);
1417
1418 if (!resize)
1419 return;
1420
1421 if (resize->hpt.virt)
1422 kvmppc_free_hpt(&resize->hpt);
1423
1424 kvm->arch.resize_hpt = NULL;
1425 kfree(resize);
1426 }
1427
1428 static void resize_hpt_prepare_work(struct work_struct *work)
1429 {
1430 struct kvm_resize_hpt *resize = container_of(work,
1431 struct kvm_resize_hpt,
1432 work);
1433 struct kvm *kvm = resize->kvm;
1434 int err;
1435
1436 resize_hpt_debug(resize, "resize_hpt_prepare_work(): order = %d\n",
1437 resize->order);
1438
1439 err = resize_hpt_allocate(resize);
1440
1441 mutex_lock(&kvm->lock);
1442
1443 resize->error = err;
1444 resize->prepare_done = true;
1445
1446 mutex_unlock(&kvm->lock);
1447 }
1448
1449 long kvm_vm_ioctl_resize_hpt_prepare(struct kvm *kvm,
1450 struct kvm_ppc_resize_hpt *rhpt)
1451 {
1452 unsigned long flags = rhpt->flags;
1453 unsigned long shift = rhpt->shift;
1454 struct kvm_resize_hpt *resize;
1455 int ret;
1456
1457 if (flags != 0)
1458 return -EINVAL;
1459
1460 if (shift && ((shift < 18) || (shift > 46)))
1461 return -EINVAL;
1462
1463 mutex_lock(&kvm->lock);
1464
1465 resize = kvm->arch.resize_hpt;
1466
1467 if (resize) {
1468 if (resize->order == shift) {
1469 /* Suitable resize in progress */
1470 if (resize->prepare_done) {
1471 ret = resize->error;
1472 if (ret != 0)
1473 resize_hpt_release(kvm, resize);
1474 } else {
1475 ret = 100; /* estimated time in ms */
1476 }
1477
1478 goto out;
1479 }
1480
1481 /* not suitable, cancel it */
1482 resize_hpt_release(kvm, resize);
1483 }
1484
1485 ret = 0;
1486 if (!shift)
1487 goto out; /* nothing to do */
1488
1489 /* start new resize */
1490
1491 resize = kzalloc(sizeof(*resize), GFP_KERNEL);
1492 if (!resize) {
1493 ret = -ENOMEM;
1494 goto out;
1495 }
1496 resize->order = shift;
1497 resize->kvm = kvm;
1498 INIT_WORK(&resize->work, resize_hpt_prepare_work);
1499 kvm->arch.resize_hpt = resize;
1500
1501 schedule_work(&resize->work);
1502
1503 ret = 100; /* estimated time in ms */
1504
1505 out:
1506 mutex_unlock(&kvm->lock);
1507 return ret;
1508 }
1509
1510 static void resize_hpt_boot_vcpu(void *opaque)
1511 {
1512 /* Nothing to do, just force a KVM exit */
1513 }
1514
1515 long kvm_vm_ioctl_resize_hpt_commit(struct kvm *kvm,
1516 struct kvm_ppc_resize_hpt *rhpt)
1517 {
1518 unsigned long flags = rhpt->flags;
1519 unsigned long shift = rhpt->shift;
1520 struct kvm_resize_hpt *resize;
1521 long ret;
1522
1523 if (flags != 0)
1524 return -EINVAL;
1525
1526 if (shift && ((shift < 18) || (shift > 46)))
1527 return -EINVAL;
1528
1529 mutex_lock(&kvm->lock);
1530
1531 resize = kvm->arch.resize_hpt;
1532
1533 /* This shouldn't be possible */
1534 ret = -EIO;
1535 if (WARN_ON(!kvm->arch.hpte_setup_done))
1536 goto out_no_hpt;
1537
1538 /* Stop VCPUs from running while we mess with the HPT */
1539 kvm->arch.hpte_setup_done = 0;
1540 smp_mb();
1541
1542 /* Boot all CPUs out of the guest so they re-read
1543 * hpte_setup_done */
1544 on_each_cpu(resize_hpt_boot_vcpu, NULL, 1);
1545
1546 ret = -ENXIO;
1547 if (!resize || (resize->order != shift))
1548 goto out;
1549
1550 ret = -EBUSY;
1551 if (!resize->prepare_done)
1552 goto out;
1553
1554 ret = resize->error;
1555 if (ret != 0)
1556 goto out;
1557
1558 ret = resize_hpt_rehash(resize);
1559 if (ret != 0)
1560 goto out;
1561
1562 resize_hpt_pivot(resize);
1563
1564 out:
1565 /* Let VCPUs run again */
1566 kvm->arch.hpte_setup_done = 1;
1567 smp_mb();
1568 out_no_hpt:
1569 resize_hpt_release(kvm, resize);
1570 mutex_unlock(&kvm->lock);
1571 return ret;
1572 }
1573
1574 /*
1575 * Functions for reading and writing the hash table via reads and
1576 * writes on a file descriptor.
1577 *
1578 * Reads return the guest view of the hash table, which has to be
1579 * pieced together from the real hash table and the guest_rpte
1580 * values in the revmap array.
1581 *
1582 * On writes, each HPTE written is considered in turn, and if it
1583 * is valid, it is written to the HPT as if an H_ENTER with the
1584 * exact flag set was done. When the invalid count is non-zero
1585 * in the header written to the stream, the kernel will make
1586 * sure that that many HPTEs are invalid, and invalidate them
1587 * if not.
1588 */
1589
1590 struct kvm_htab_ctx {
1591 unsigned long index;
1592 unsigned long flags;
1593 struct kvm *kvm;
1594 int first_pass;
1595 };
1596
1597 #define HPTE_SIZE (2 * sizeof(unsigned long))
1598
1599 /*
1600 * Returns 1 if this HPT entry has been modified or has pending
1601 * R/C bit changes.
1602 */
1603 static int hpte_dirty(struct revmap_entry *revp, __be64 *hptp)
1604 {
1605 unsigned long rcbits_unset;
1606
1607 if (revp->guest_rpte & HPTE_GR_MODIFIED)
1608 return 1;
1609
1610 /* Also need to consider changes in reference and changed bits */
1611 rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C);
1612 if ((be64_to_cpu(hptp[0]) & HPTE_V_VALID) &&
1613 (be64_to_cpu(hptp[1]) & rcbits_unset))
1614 return 1;
1615
1616 return 0;
1617 }
1618
1619 static long record_hpte(unsigned long flags, __be64 *hptp,
1620 unsigned long *hpte, struct revmap_entry *revp,
1621 int want_valid, int first_pass)
1622 {
1623 unsigned long v, r, hr;
1624 unsigned long rcbits_unset;
1625 int ok = 1;
1626 int valid, dirty;
1627
1628 /* Unmodified entries are uninteresting except on the first pass */
1629 dirty = hpte_dirty(revp, hptp);
1630 if (!first_pass && !dirty)
1631 return 0;
1632
1633 valid = 0;
1634 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)) {
1635 valid = 1;
1636 if ((flags & KVM_GET_HTAB_BOLTED_ONLY) &&
1637 !(be64_to_cpu(hptp[0]) & HPTE_V_BOLTED))
1638 valid = 0;
1639 }
1640 if (valid != want_valid)
1641 return 0;
1642
1643 v = r = 0;
1644 if (valid || dirty) {
1645 /* lock the HPTE so it's stable and read it */
1646 preempt_disable();
1647 while (!try_lock_hpte(hptp, HPTE_V_HVLOCK))
1648 cpu_relax();
1649 v = be64_to_cpu(hptp[0]);
1650 hr = be64_to_cpu(hptp[1]);
1651 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1652 v = hpte_new_to_old_v(v, hr);
1653 hr = hpte_new_to_old_r(hr);
1654 }
1655
1656 /* re-evaluate valid and dirty from synchronized HPTE value */
1657 valid = !!(v & HPTE_V_VALID);
1658 dirty = !!(revp->guest_rpte & HPTE_GR_MODIFIED);
1659
1660 /* Harvest R and C into guest view if necessary */
1661 rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C);
1662 if (valid && (rcbits_unset & hr)) {
1663 revp->guest_rpte |= (hr &
1664 (HPTE_R_R | HPTE_R_C)) | HPTE_GR_MODIFIED;
1665 dirty = 1;
1666 }
1667
1668 if (v & HPTE_V_ABSENT) {
1669 v &= ~HPTE_V_ABSENT;
1670 v |= HPTE_V_VALID;
1671 valid = 1;
1672 }
1673 if ((flags & KVM_GET_HTAB_BOLTED_ONLY) && !(v & HPTE_V_BOLTED))
1674 valid = 0;
1675
1676 r = revp->guest_rpte;
1677 /* only clear modified if this is the right sort of entry */
1678 if (valid == want_valid && dirty) {
1679 r &= ~HPTE_GR_MODIFIED;
1680 revp->guest_rpte = r;
1681 }
1682 unlock_hpte(hptp, be64_to_cpu(hptp[0]));
1683 preempt_enable();
1684 if (!(valid == want_valid && (first_pass || dirty)))
1685 ok = 0;
1686 }
1687 hpte[0] = cpu_to_be64(v);
1688 hpte[1] = cpu_to_be64(r);
1689 return ok;
1690 }
1691
1692 static ssize_t kvm_htab_read(struct file *file, char __user *buf,
1693 size_t count, loff_t *ppos)
1694 {
1695 struct kvm_htab_ctx *ctx = file->private_data;
1696 struct kvm *kvm = ctx->kvm;
1697 struct kvm_get_htab_header hdr;
1698 __be64 *hptp;
1699 struct revmap_entry *revp;
1700 unsigned long i, nb, nw;
1701 unsigned long __user *lbuf;
1702 struct kvm_get_htab_header __user *hptr;
1703 unsigned long flags;
1704 int first_pass;
1705 unsigned long hpte[2];
1706
1707 if (!access_ok(VERIFY_WRITE, buf, count))
1708 return -EFAULT;
1709
1710 first_pass = ctx->first_pass;
1711 flags = ctx->flags;
1712
1713 i = ctx->index;
1714 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
1715 revp = kvm->arch.hpt.rev + i;
1716 lbuf = (unsigned long __user *)buf;
1717
1718 nb = 0;
1719 while (nb + sizeof(hdr) + HPTE_SIZE < count) {
1720 /* Initialize header */
1721 hptr = (struct kvm_get_htab_header __user *)buf;
1722 hdr.n_valid = 0;
1723 hdr.n_invalid = 0;
1724 nw = nb;
1725 nb += sizeof(hdr);
1726 lbuf = (unsigned long __user *)(buf + sizeof(hdr));
1727
1728 /* Skip uninteresting entries, i.e. clean on not-first pass */
1729 if (!first_pass) {
1730 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1731 !hpte_dirty(revp, hptp)) {
1732 ++i;
1733 hptp += 2;
1734 ++revp;
1735 }
1736 }
1737 hdr.index = i;
1738
1739 /* Grab a series of valid entries */
1740 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1741 hdr.n_valid < 0xffff &&
1742 nb + HPTE_SIZE < count &&
1743 record_hpte(flags, hptp, hpte, revp, 1, first_pass)) {
1744 /* valid entry, write it out */
1745 ++hdr.n_valid;
1746 if (__put_user(hpte[0], lbuf) ||
1747 __put_user(hpte[1], lbuf + 1))
1748 return -EFAULT;
1749 nb += HPTE_SIZE;
1750 lbuf += 2;
1751 ++i;
1752 hptp += 2;
1753 ++revp;
1754 }
1755 /* Now skip invalid entries while we can */
1756 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1757 hdr.n_invalid < 0xffff &&
1758 record_hpte(flags, hptp, hpte, revp, 0, first_pass)) {
1759 /* found an invalid entry */
1760 ++hdr.n_invalid;
1761 ++i;
1762 hptp += 2;
1763 ++revp;
1764 }
1765
1766 if (hdr.n_valid || hdr.n_invalid) {
1767 /* write back the header */
1768 if (__copy_to_user(hptr, &hdr, sizeof(hdr)))
1769 return -EFAULT;
1770 nw = nb;
1771 buf = (char __user *)lbuf;
1772 } else {
1773 nb = nw;
1774 }
1775
1776 /* Check if we've wrapped around the hash table */
1777 if (i >= kvmppc_hpt_npte(&kvm->arch.hpt)) {
1778 i = 0;
1779 ctx->first_pass = 0;
1780 break;
1781 }
1782 }
1783
1784 ctx->index = i;
1785
1786 return nb;
1787 }
1788
1789 static ssize_t kvm_htab_write(struct file *file, const char __user *buf,
1790 size_t count, loff_t *ppos)
1791 {
1792 struct kvm_htab_ctx *ctx = file->private_data;
1793 struct kvm *kvm = ctx->kvm;
1794 struct kvm_get_htab_header hdr;
1795 unsigned long i, j;
1796 unsigned long v, r;
1797 unsigned long __user *lbuf;
1798 __be64 *hptp;
1799 unsigned long tmp[2];
1800 ssize_t nb;
1801 long int err, ret;
1802 int hpte_setup;
1803
1804 if (!access_ok(VERIFY_READ, buf, count))
1805 return -EFAULT;
1806
1807 /* lock out vcpus from running while we're doing this */
1808 mutex_lock(&kvm->lock);
1809 hpte_setup = kvm->arch.hpte_setup_done;
1810 if (hpte_setup) {
1811 kvm->arch.hpte_setup_done = 0; /* temporarily */
1812 /* order hpte_setup_done vs. vcpus_running */
1813 smp_mb();
1814 if (atomic_read(&kvm->arch.vcpus_running)) {
1815 kvm->arch.hpte_setup_done = 1;
1816 mutex_unlock(&kvm->lock);
1817 return -EBUSY;
1818 }
1819 }
1820
1821 err = 0;
1822 for (nb = 0; nb + sizeof(hdr) <= count; ) {
1823 err = -EFAULT;
1824 if (__copy_from_user(&hdr, buf, sizeof(hdr)))
1825 break;
1826
1827 err = 0;
1828 if (nb + hdr.n_valid * HPTE_SIZE > count)
1829 break;
1830
1831 nb += sizeof(hdr);
1832 buf += sizeof(hdr);
1833
1834 err = -EINVAL;
1835 i = hdr.index;
1836 if (i >= kvmppc_hpt_npte(&kvm->arch.hpt) ||
1837 i + hdr.n_valid + hdr.n_invalid > kvmppc_hpt_npte(&kvm->arch.hpt))
1838 break;
1839
1840 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
1841 lbuf = (unsigned long __user *)buf;
1842 for (j = 0; j < hdr.n_valid; ++j) {
1843 __be64 hpte_v;
1844 __be64 hpte_r;
1845
1846 err = -EFAULT;
1847 if (__get_user(hpte_v, lbuf) ||
1848 __get_user(hpte_r, lbuf + 1))
1849 goto out;
1850 v = be64_to_cpu(hpte_v);
1851 r = be64_to_cpu(hpte_r);
1852 err = -EINVAL;
1853 if (!(v & HPTE_V_VALID))
1854 goto out;
1855 lbuf += 2;
1856 nb += HPTE_SIZE;
1857
1858 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT))
1859 kvmppc_do_h_remove(kvm, 0, i, 0, tmp);
1860 err = -EIO;
1861 ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, i, v, r,
1862 tmp);
1863 if (ret != H_SUCCESS) {
1864 pr_err("kvm_htab_write ret %ld i=%ld v=%lx "
1865 "r=%lx\n", ret, i, v, r);
1866 goto out;
1867 }
1868 if (!hpte_setup && is_vrma_hpte(v)) {
1869 unsigned long psize = hpte_base_page_size(v, r);
1870 unsigned long senc = slb_pgsize_encoding(psize);
1871 unsigned long lpcr;
1872
1873 kvm->arch.vrma_slb_v = senc | SLB_VSID_B_1T |
1874 (VRMA_VSID << SLB_VSID_SHIFT_1T);
1875 lpcr = senc << (LPCR_VRMASD_SH - 4);
1876 kvmppc_update_lpcr(kvm, lpcr, LPCR_VRMASD);
1877 hpte_setup = 1;
1878 }
1879 ++i;
1880 hptp += 2;
1881 }
1882
1883 for (j = 0; j < hdr.n_invalid; ++j) {
1884 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT))
1885 kvmppc_do_h_remove(kvm, 0, i, 0, tmp);
1886 ++i;
1887 hptp += 2;
1888 }
1889 err = 0;
1890 }
1891
1892 out:
1893 /* Order HPTE updates vs. hpte_setup_done */
1894 smp_wmb();
1895 kvm->arch.hpte_setup_done = hpte_setup;
1896 mutex_unlock(&kvm->lock);
1897
1898 if (err)
1899 return err;
1900 return nb;
1901 }
1902
1903 static int kvm_htab_release(struct inode *inode, struct file *filp)
1904 {
1905 struct kvm_htab_ctx *ctx = filp->private_data;
1906
1907 filp->private_data = NULL;
1908 if (!(ctx->flags & KVM_GET_HTAB_WRITE))
1909 atomic_dec(&ctx->kvm->arch.hpte_mod_interest);
1910 kvm_put_kvm(ctx->kvm);
1911 kfree(ctx);
1912 return 0;
1913 }
1914
1915 static const struct file_operations kvm_htab_fops = {
1916 .read = kvm_htab_read,
1917 .write = kvm_htab_write,
1918 .llseek = default_llseek,
1919 .release = kvm_htab_release,
1920 };
1921
1922 int kvm_vm_ioctl_get_htab_fd(struct kvm *kvm, struct kvm_get_htab_fd *ghf)
1923 {
1924 int ret;
1925 struct kvm_htab_ctx *ctx;
1926 int rwflag;
1927
1928 /* reject flags we don't recognize */
1929 if (ghf->flags & ~(KVM_GET_HTAB_BOLTED_ONLY | KVM_GET_HTAB_WRITE))
1930 return -EINVAL;
1931 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1932 if (!ctx)
1933 return -ENOMEM;
1934 kvm_get_kvm(kvm);
1935 ctx->kvm = kvm;
1936 ctx->index = ghf->start_index;
1937 ctx->flags = ghf->flags;
1938 ctx->first_pass = 1;
1939
1940 rwflag = (ghf->flags & KVM_GET_HTAB_WRITE) ? O_WRONLY : O_RDONLY;
1941 ret = anon_inode_getfd("kvm-htab", &kvm_htab_fops, ctx, rwflag | O_CLOEXEC);
1942 if (ret < 0) {
1943 kvm_put_kvm(kvm);
1944 return ret;
1945 }
1946
1947 if (rwflag == O_RDONLY) {
1948 mutex_lock(&kvm->slots_lock);
1949 atomic_inc(&kvm->arch.hpte_mod_interest);
1950 /* make sure kvmppc_do_h_enter etc. see the increment */
1951 synchronize_srcu_expedited(&kvm->srcu);
1952 mutex_unlock(&kvm->slots_lock);
1953 }
1954
1955 return ret;
1956 }
1957
1958 struct debugfs_htab_state {
1959 struct kvm *kvm;
1960 struct mutex mutex;
1961 unsigned long hpt_index;
1962 int chars_left;
1963 int buf_index;
1964 char buf[64];
1965 };
1966
1967 static int debugfs_htab_open(struct inode *inode, struct file *file)
1968 {
1969 struct kvm *kvm = inode->i_private;
1970 struct debugfs_htab_state *p;
1971
1972 p = kzalloc(sizeof(*p), GFP_KERNEL);
1973 if (!p)
1974 return -ENOMEM;
1975
1976 kvm_get_kvm(kvm);
1977 p->kvm = kvm;
1978 mutex_init(&p->mutex);
1979 file->private_data = p;
1980
1981 return nonseekable_open(inode, file);
1982 }
1983
1984 static int debugfs_htab_release(struct inode *inode, struct file *file)
1985 {
1986 struct debugfs_htab_state *p = file->private_data;
1987
1988 kvm_put_kvm(p->kvm);
1989 kfree(p);
1990 return 0;
1991 }
1992
1993 static ssize_t debugfs_htab_read(struct file *file, char __user *buf,
1994 size_t len, loff_t *ppos)
1995 {
1996 struct debugfs_htab_state *p = file->private_data;
1997 ssize_t ret, r;
1998 unsigned long i, n;
1999 unsigned long v, hr, gr;
2000 struct kvm *kvm;
2001 __be64 *hptp;
2002
2003 ret = mutex_lock_interruptible(&p->mutex);
2004 if (ret)
2005 return ret;
2006
2007 if (p->chars_left) {
2008 n = p->chars_left;
2009 if (n > len)
2010 n = len;
2011 r = copy_to_user(buf, p->buf + p->buf_index, n);
2012 n -= r;
2013 p->chars_left -= n;
2014 p->buf_index += n;
2015 buf += n;
2016 len -= n;
2017 ret = n;
2018 if (r) {
2019 if (!n)
2020 ret = -EFAULT;
2021 goto out;
2022 }
2023 }
2024
2025 kvm = p->kvm;
2026 i = p->hpt_index;
2027 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
2028 for (; len != 0 && i < kvmppc_hpt_npte(&kvm->arch.hpt);
2029 ++i, hptp += 2) {
2030 if (!(be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)))
2031 continue;
2032
2033 /* lock the HPTE so it's stable and read it */
2034 preempt_disable();
2035 while (!try_lock_hpte(hptp, HPTE_V_HVLOCK))
2036 cpu_relax();
2037 v = be64_to_cpu(hptp[0]) & ~HPTE_V_HVLOCK;
2038 hr = be64_to_cpu(hptp[1]);
2039 gr = kvm->arch.hpt.rev[i].guest_rpte;
2040 unlock_hpte(hptp, v);
2041 preempt_enable();
2042
2043 if (!(v & (HPTE_V_VALID | HPTE_V_ABSENT)))
2044 continue;
2045
2046 n = scnprintf(p->buf, sizeof(p->buf),
2047 "%6lx %.16lx %.16lx %.16lx\n",
2048 i, v, hr, gr);
2049 p->chars_left = n;
2050 if (n > len)
2051 n = len;
2052 r = copy_to_user(buf, p->buf, n);
2053 n -= r;
2054 p->chars_left -= n;
2055 p->buf_index = n;
2056 buf += n;
2057 len -= n;
2058 ret += n;
2059 if (r) {
2060 if (!ret)
2061 ret = -EFAULT;
2062 goto out;
2063 }
2064 }
2065 p->hpt_index = i;
2066
2067 out:
2068 mutex_unlock(&p->mutex);
2069 return ret;
2070 }
2071
2072 static ssize_t debugfs_htab_write(struct file *file, const char __user *buf,
2073 size_t len, loff_t *ppos)
2074 {
2075 return -EACCES;
2076 }
2077
2078 static const struct file_operations debugfs_htab_fops = {
2079 .owner = THIS_MODULE,
2080 .open = debugfs_htab_open,
2081 .release = debugfs_htab_release,
2082 .read = debugfs_htab_read,
2083 .write = debugfs_htab_write,
2084 .llseek = generic_file_llseek,
2085 };
2086
2087 void kvmppc_mmu_debugfs_init(struct kvm *kvm)
2088 {
2089 kvm->arch.htab_dentry = debugfs_create_file("htab", 0400,
2090 kvm->arch.debugfs_dir, kvm,
2091 &debugfs_htab_fops);
2092 }
2093
2094 void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu)
2095 {
2096 struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
2097
2098 vcpu->arch.slb_nr = 32; /* POWER7/POWER8 */
2099
2100 if (kvm_is_radix(vcpu->kvm))
2101 mmu->xlate = kvmppc_mmu_radix_xlate;
2102 else
2103 mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate;
2104 mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr;
2105
2106 vcpu->arch.hflags |= BOOK3S_HFLAG_SLB;
2107 }
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