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[mirror_ubuntu-focal-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 #include <asm/pte-walk.h>
41
42 #include "trace_hv.h"
43
44 //#define DEBUG_RESIZE_HPT 1
45
46 #ifdef DEBUG_RESIZE_HPT
47 #define resize_hpt_debug(resize, ...) \
48 do { \
49 printk(KERN_DEBUG "RESIZE HPT %p: ", resize); \
50 printk(__VA_ARGS__); \
51 } while (0)
52 #else
53 #define resize_hpt_debug(resize, ...) \
54 do { } while (0)
55 #endif
56
57 static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
58 long pte_index, unsigned long pteh,
59 unsigned long ptel, unsigned long *pte_idx_ret);
60
61 struct kvm_resize_hpt {
62 /* These fields read-only after init */
63 struct kvm *kvm;
64 struct work_struct work;
65 u32 order;
66
67 /* These fields protected by kvm->lock */
68
69 /* Possible values and their usage:
70 * <0 an error occurred during allocation,
71 * -EBUSY allocation is in the progress,
72 * 0 allocation made successfuly.
73 */
74 int error;
75
76 /* Private to the work thread, until error != -EBUSY,
77 * then protected by kvm->lock.
78 */
79 struct kvm_hpt_info hpt;
80 };
81
82 int kvmppc_allocate_hpt(struct kvm_hpt_info *info, u32 order)
83 {
84 unsigned long hpt = 0;
85 int cma = 0;
86 struct page *page = NULL;
87 struct revmap_entry *rev;
88 unsigned long npte;
89
90 if ((order < PPC_MIN_HPT_ORDER) || (order > PPC_MAX_HPT_ORDER))
91 return -EINVAL;
92
93 page = kvm_alloc_hpt_cma(1ul << (order - PAGE_SHIFT));
94 if (page) {
95 hpt = (unsigned long)pfn_to_kaddr(page_to_pfn(page));
96 memset((void *)hpt, 0, (1ul << order));
97 cma = 1;
98 }
99
100 if (!hpt)
101 hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL
102 |__GFP_NOWARN, order - PAGE_SHIFT);
103
104 if (!hpt)
105 return -ENOMEM;
106
107 /* HPTEs are 2**4 bytes long */
108 npte = 1ul << (order - 4);
109
110 /* Allocate reverse map array */
111 rev = vmalloc(sizeof(struct revmap_entry) * npte);
112 if (!rev) {
113 if (cma)
114 kvm_free_hpt_cma(page, 1 << (order - PAGE_SHIFT));
115 else
116 free_pages(hpt, order - PAGE_SHIFT);
117 return -ENOMEM;
118 }
119
120 info->order = order;
121 info->virt = hpt;
122 info->cma = cma;
123 info->rev = rev;
124
125 return 0;
126 }
127
128 void kvmppc_set_hpt(struct kvm *kvm, struct kvm_hpt_info *info)
129 {
130 atomic64_set(&kvm->arch.mmio_update, 0);
131 kvm->arch.hpt = *info;
132 kvm->arch.sdr1 = __pa(info->virt) | (info->order - 18);
133
134 pr_debug("KVM guest htab at %lx (order %ld), LPID %x\n",
135 info->virt, (long)info->order, kvm->arch.lpid);
136 }
137
138 long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order)
139 {
140 long err = -EBUSY;
141 struct kvm_hpt_info info;
142
143 mutex_lock(&kvm->lock);
144 if (kvm->arch.mmu_ready) {
145 kvm->arch.mmu_ready = 0;
146 /* order mmu_ready vs. vcpus_running */
147 smp_mb();
148 if (atomic_read(&kvm->arch.vcpus_running)) {
149 kvm->arch.mmu_ready = 1;
150 goto out;
151 }
152 }
153 if (kvm_is_radix(kvm)) {
154 err = kvmppc_switch_mmu_to_hpt(kvm);
155 if (err)
156 goto out;
157 }
158
159 if (kvm->arch.hpt.order == order) {
160 /* We already have a suitable HPT */
161
162 /* Set the entire HPT to 0, i.e. invalid HPTEs */
163 memset((void *)kvm->arch.hpt.virt, 0, 1ul << order);
164 /*
165 * Reset all the reverse-mapping chains for all memslots
166 */
167 kvmppc_rmap_reset(kvm);
168 err = 0;
169 goto out;
170 }
171
172 if (kvm->arch.hpt.virt) {
173 kvmppc_free_hpt(&kvm->arch.hpt);
174 kvmppc_rmap_reset(kvm);
175 }
176
177 err = kvmppc_allocate_hpt(&info, order);
178 if (err < 0)
179 goto out;
180 kvmppc_set_hpt(kvm, &info);
181
182 out:
183 if (err == 0)
184 /* Ensure that each vcpu will flush its TLB on next entry. */
185 cpumask_setall(&kvm->arch.need_tlb_flush);
186
187 mutex_unlock(&kvm->lock);
188 return err;
189 }
190
191 void kvmppc_free_hpt(struct kvm_hpt_info *info)
192 {
193 vfree(info->rev);
194 info->rev = NULL;
195 if (info->cma)
196 kvm_free_hpt_cma(virt_to_page(info->virt),
197 1 << (info->order - PAGE_SHIFT));
198 else if (info->virt)
199 free_pages(info->virt, info->order - PAGE_SHIFT);
200 info->virt = 0;
201 info->order = 0;
202 }
203
204 /* Bits in first HPTE dword for pagesize 4k, 64k or 16M */
205 static inline unsigned long hpte0_pgsize_encoding(unsigned long pgsize)
206 {
207 return (pgsize > 0x1000) ? HPTE_V_LARGE : 0;
208 }
209
210 /* Bits in second HPTE dword for pagesize 4k, 64k or 16M */
211 static inline unsigned long hpte1_pgsize_encoding(unsigned long pgsize)
212 {
213 return (pgsize == 0x10000) ? 0x1000 : 0;
214 }
215
216 void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot,
217 unsigned long porder)
218 {
219 unsigned long i;
220 unsigned long npages;
221 unsigned long hp_v, hp_r;
222 unsigned long addr, hash;
223 unsigned long psize;
224 unsigned long hp0, hp1;
225 unsigned long idx_ret;
226 long ret;
227 struct kvm *kvm = vcpu->kvm;
228
229 psize = 1ul << porder;
230 npages = memslot->npages >> (porder - PAGE_SHIFT);
231
232 /* VRMA can't be > 1TB */
233 if (npages > 1ul << (40 - porder))
234 npages = 1ul << (40 - porder);
235 /* Can't use more than 1 HPTE per HPTEG */
236 if (npages > kvmppc_hpt_mask(&kvm->arch.hpt) + 1)
237 npages = kvmppc_hpt_mask(&kvm->arch.hpt) + 1;
238
239 hp0 = HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)) |
240 HPTE_V_BOLTED | hpte0_pgsize_encoding(psize);
241 hp1 = hpte1_pgsize_encoding(psize) |
242 HPTE_R_R | HPTE_R_C | HPTE_R_M | PP_RWXX;
243
244 for (i = 0; i < npages; ++i) {
245 addr = i << porder;
246 /* can't use hpt_hash since va > 64 bits */
247 hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25)))
248 & kvmppc_hpt_mask(&kvm->arch.hpt);
249 /*
250 * We assume that the hash table is empty and no
251 * vcpus are using it at this stage. Since we create
252 * at most one HPTE per HPTEG, we just assume entry 7
253 * is available and use it.
254 */
255 hash = (hash << 3) + 7;
256 hp_v = hp0 | ((addr >> 16) & ~0x7fUL);
257 hp_r = hp1 | addr;
258 ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, hash, hp_v, hp_r,
259 &idx_ret);
260 if (ret != H_SUCCESS) {
261 pr_err("KVM: map_vrma at %lx failed, ret=%ld\n",
262 addr, ret);
263 break;
264 }
265 }
266 }
267
268 int kvmppc_mmu_hv_init(void)
269 {
270 unsigned long host_lpid, rsvd_lpid;
271
272 if (!cpu_has_feature(CPU_FTR_HVMODE))
273 return -EINVAL;
274
275 /* POWER7 has 10-bit LPIDs (12-bit in POWER8) */
276 host_lpid = mfspr(SPRN_LPID);
277 rsvd_lpid = LPID_RSVD;
278
279 kvmppc_init_lpid(rsvd_lpid + 1);
280
281 kvmppc_claim_lpid(host_lpid);
282 /* rsvd_lpid is reserved for use in partition switching */
283 kvmppc_claim_lpid(rsvd_lpid);
284
285 return 0;
286 }
287
288 static void kvmppc_mmu_book3s_64_hv_reset_msr(struct kvm_vcpu *vcpu)
289 {
290 unsigned long msr = vcpu->arch.intr_msr;
291
292 /* If transactional, change to suspend mode on IRQ delivery */
293 if (MSR_TM_TRANSACTIONAL(vcpu->arch.shregs.msr))
294 msr |= MSR_TS_S;
295 else
296 msr |= vcpu->arch.shregs.msr & MSR_TS_MASK;
297 kvmppc_set_msr(vcpu, msr);
298 }
299
300 static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
301 long pte_index, unsigned long pteh,
302 unsigned long ptel, unsigned long *pte_idx_ret)
303 {
304 long ret;
305
306 /* Protect linux PTE lookup from page table destruction */
307 rcu_read_lock_sched(); /* this disables preemption too */
308 ret = kvmppc_do_h_enter(kvm, flags, pte_index, pteh, ptel,
309 current->mm->pgd, false, pte_idx_ret);
310 rcu_read_unlock_sched();
311 if (ret == H_TOO_HARD) {
312 /* this can't happen */
313 pr_err("KVM: Oops, kvmppc_h_enter returned too hard!\n");
314 ret = H_RESOURCE; /* or something */
315 }
316 return ret;
317
318 }
319
320 static struct kvmppc_slb *kvmppc_mmu_book3s_hv_find_slbe(struct kvm_vcpu *vcpu,
321 gva_t eaddr)
322 {
323 u64 mask;
324 int i;
325
326 for (i = 0; i < vcpu->arch.slb_nr; i++) {
327 if (!(vcpu->arch.slb[i].orige & SLB_ESID_V))
328 continue;
329
330 if (vcpu->arch.slb[i].origv & SLB_VSID_B_1T)
331 mask = ESID_MASK_1T;
332 else
333 mask = ESID_MASK;
334
335 if (((vcpu->arch.slb[i].orige ^ eaddr) & mask) == 0)
336 return &vcpu->arch.slb[i];
337 }
338 return NULL;
339 }
340
341 static unsigned long kvmppc_mmu_get_real_addr(unsigned long v, unsigned long r,
342 unsigned long ea)
343 {
344 unsigned long ra_mask;
345
346 ra_mask = kvmppc_actual_pgsz(v, r) - 1;
347 return (r & HPTE_R_RPN & ~ra_mask) | (ea & ra_mask);
348 }
349
350 static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
351 struct kvmppc_pte *gpte, bool data, bool iswrite)
352 {
353 struct kvm *kvm = vcpu->kvm;
354 struct kvmppc_slb *slbe;
355 unsigned long slb_v;
356 unsigned long pp, key;
357 unsigned long v, orig_v, gr;
358 __be64 *hptep;
359 int index;
360 int virtmode = vcpu->arch.shregs.msr & (data ? MSR_DR : MSR_IR);
361
362 if (kvm_is_radix(vcpu->kvm))
363 return kvmppc_mmu_radix_xlate(vcpu, eaddr, gpte, data, iswrite);
364
365 /* Get SLB entry */
366 if (virtmode) {
367 slbe = kvmppc_mmu_book3s_hv_find_slbe(vcpu, eaddr);
368 if (!slbe)
369 return -EINVAL;
370 slb_v = slbe->origv;
371 } else {
372 /* real mode access */
373 slb_v = vcpu->kvm->arch.vrma_slb_v;
374 }
375
376 preempt_disable();
377 /* Find the HPTE in the hash table */
378 index = kvmppc_hv_find_lock_hpte(kvm, eaddr, slb_v,
379 HPTE_V_VALID | HPTE_V_ABSENT);
380 if (index < 0) {
381 preempt_enable();
382 return -ENOENT;
383 }
384 hptep = (__be64 *)(kvm->arch.hpt.virt + (index << 4));
385 v = orig_v = be64_to_cpu(hptep[0]) & ~HPTE_V_HVLOCK;
386 if (cpu_has_feature(CPU_FTR_ARCH_300))
387 v = hpte_new_to_old_v(v, be64_to_cpu(hptep[1]));
388 gr = kvm->arch.hpt.rev[index].guest_rpte;
389
390 unlock_hpte(hptep, orig_v);
391 preempt_enable();
392
393 gpte->eaddr = eaddr;
394 gpte->vpage = ((v & HPTE_V_AVPN) << 4) | ((eaddr >> 12) & 0xfff);
395
396 /* Get PP bits and key for permission check */
397 pp = gr & (HPTE_R_PP0 | HPTE_R_PP);
398 key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;
399 key &= slb_v;
400
401 /* Calculate permissions */
402 gpte->may_read = hpte_read_permission(pp, key);
403 gpte->may_write = hpte_write_permission(pp, key);
404 gpte->may_execute = gpte->may_read && !(gr & (HPTE_R_N | HPTE_R_G));
405
406 /* Storage key permission check for POWER7 */
407 if (data && virtmode) {
408 int amrfield = hpte_get_skey_perm(gr, vcpu->arch.amr);
409 if (amrfield & 1)
410 gpte->may_read = 0;
411 if (amrfield & 2)
412 gpte->may_write = 0;
413 }
414
415 /* Get the guest physical address */
416 gpte->raddr = kvmppc_mmu_get_real_addr(v, gr, eaddr);
417 return 0;
418 }
419
420 /*
421 * Quick test for whether an instruction is a load or a store.
422 * If the instruction is a load or a store, then this will indicate
423 * which it is, at least on server processors. (Embedded processors
424 * have some external PID instructions that don't follow the rule
425 * embodied here.) If the instruction isn't a load or store, then
426 * this doesn't return anything useful.
427 */
428 static int instruction_is_store(unsigned int instr)
429 {
430 unsigned int mask;
431
432 mask = 0x10000000;
433 if ((instr & 0xfc000000) == 0x7c000000)
434 mask = 0x100; /* major opcode 31 */
435 return (instr & mask) != 0;
436 }
437
438 int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu,
439 unsigned long gpa, gva_t ea, int is_store)
440 {
441 u32 last_inst;
442
443 /*
444 * If we fail, we just return to the guest and try executing it again.
445 */
446 if (kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst) !=
447 EMULATE_DONE)
448 return RESUME_GUEST;
449
450 /*
451 * WARNING: We do not know for sure whether the instruction we just
452 * read from memory is the same that caused the fault in the first
453 * place. If the instruction we read is neither an load or a store,
454 * then it can't access memory, so we don't need to worry about
455 * enforcing access permissions. So, assuming it is a load or
456 * store, we just check that its direction (load or store) is
457 * consistent with the original fault, since that's what we
458 * checked the access permissions against. If there is a mismatch
459 * we just return and retry the instruction.
460 */
461
462 if (instruction_is_store(last_inst) != !!is_store)
463 return RESUME_GUEST;
464
465 /*
466 * Emulated accesses are emulated by looking at the hash for
467 * translation once, then performing the access later. The
468 * translation could be invalidated in the meantime in which
469 * point performing the subsequent memory access on the old
470 * physical address could possibly be a security hole for the
471 * guest (but not the host).
472 *
473 * This is less of an issue for MMIO stores since they aren't
474 * globally visible. It could be an issue for MMIO loads to
475 * a certain extent but we'll ignore it for now.
476 */
477
478 vcpu->arch.paddr_accessed = gpa;
479 vcpu->arch.vaddr_accessed = ea;
480 return kvmppc_emulate_mmio(run, vcpu);
481 }
482
483 int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
484 unsigned long ea, unsigned long dsisr)
485 {
486 struct kvm *kvm = vcpu->kvm;
487 unsigned long hpte[3], r;
488 unsigned long hnow_v, hnow_r;
489 __be64 *hptep;
490 unsigned long mmu_seq, psize, pte_size;
491 unsigned long gpa_base, gfn_base;
492 unsigned long gpa, gfn, hva, pfn;
493 struct kvm_memory_slot *memslot;
494 unsigned long *rmap;
495 struct revmap_entry *rev;
496 struct page *page, *pages[1];
497 long index, ret, npages;
498 bool is_ci;
499 unsigned int writing, write_ok;
500 struct vm_area_struct *vma;
501 unsigned long rcbits;
502 long mmio_update;
503
504 if (kvm_is_radix(kvm))
505 return kvmppc_book3s_radix_page_fault(run, vcpu, ea, dsisr);
506
507 /*
508 * Real-mode code has already searched the HPT and found the
509 * entry we're interested in. Lock the entry and check that
510 * it hasn't changed. If it has, just return and re-execute the
511 * instruction.
512 */
513 if (ea != vcpu->arch.pgfault_addr)
514 return RESUME_GUEST;
515
516 if (vcpu->arch.pgfault_cache) {
517 mmio_update = atomic64_read(&kvm->arch.mmio_update);
518 if (mmio_update == vcpu->arch.pgfault_cache->mmio_update) {
519 r = vcpu->arch.pgfault_cache->rpte;
520 psize = kvmppc_actual_pgsz(vcpu->arch.pgfault_hpte[0],
521 r);
522 gpa_base = r & HPTE_R_RPN & ~(psize - 1);
523 gfn_base = gpa_base >> PAGE_SHIFT;
524 gpa = gpa_base | (ea & (psize - 1));
525 return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
526 dsisr & DSISR_ISSTORE);
527 }
528 }
529 index = vcpu->arch.pgfault_index;
530 hptep = (__be64 *)(kvm->arch.hpt.virt + (index << 4));
531 rev = &kvm->arch.hpt.rev[index];
532 preempt_disable();
533 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
534 cpu_relax();
535 hpte[0] = be64_to_cpu(hptep[0]) & ~HPTE_V_HVLOCK;
536 hpte[1] = be64_to_cpu(hptep[1]);
537 hpte[2] = r = rev->guest_rpte;
538 unlock_hpte(hptep, hpte[0]);
539 preempt_enable();
540
541 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
542 hpte[0] = hpte_new_to_old_v(hpte[0], hpte[1]);
543 hpte[1] = hpte_new_to_old_r(hpte[1]);
544 }
545 if (hpte[0] != vcpu->arch.pgfault_hpte[0] ||
546 hpte[1] != vcpu->arch.pgfault_hpte[1])
547 return RESUME_GUEST;
548
549 /* Translate the logical address and get the page */
550 psize = kvmppc_actual_pgsz(hpte[0], r);
551 gpa_base = r & HPTE_R_RPN & ~(psize - 1);
552 gfn_base = gpa_base >> PAGE_SHIFT;
553 gpa = gpa_base | (ea & (psize - 1));
554 gfn = gpa >> PAGE_SHIFT;
555 memslot = gfn_to_memslot(kvm, gfn);
556
557 trace_kvm_page_fault_enter(vcpu, hpte, memslot, ea, dsisr);
558
559 /* No memslot means it's an emulated MMIO region */
560 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
561 return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
562 dsisr & DSISR_ISSTORE);
563
564 /*
565 * This should never happen, because of the slot_is_aligned()
566 * check in kvmppc_do_h_enter().
567 */
568 if (gfn_base < memslot->base_gfn)
569 return -EFAULT;
570
571 /* used to check for invalidations in progress */
572 mmu_seq = kvm->mmu_notifier_seq;
573 smp_rmb();
574
575 ret = -EFAULT;
576 is_ci = false;
577 pfn = 0;
578 page = NULL;
579 pte_size = PAGE_SIZE;
580 writing = (dsisr & DSISR_ISSTORE) != 0;
581 /* If writing != 0, then the HPTE must allow writing, if we get here */
582 write_ok = writing;
583 hva = gfn_to_hva_memslot(memslot, gfn);
584 npages = get_user_pages_fast(hva, 1, writing, pages);
585 if (npages < 1) {
586 /* Check if it's an I/O mapping */
587 down_read(&current->mm->mmap_sem);
588 vma = find_vma(current->mm, hva);
589 if (vma && vma->vm_start <= hva && hva + psize <= vma->vm_end &&
590 (vma->vm_flags & VM_PFNMAP)) {
591 pfn = vma->vm_pgoff +
592 ((hva - vma->vm_start) >> PAGE_SHIFT);
593 pte_size = psize;
594 is_ci = pte_ci(__pte((pgprot_val(vma->vm_page_prot))));
595 write_ok = vma->vm_flags & VM_WRITE;
596 }
597 up_read(&current->mm->mmap_sem);
598 if (!pfn)
599 goto out_put;
600 } else {
601 page = pages[0];
602 pfn = page_to_pfn(page);
603 if (PageHuge(page)) {
604 page = compound_head(page);
605 pte_size <<= compound_order(page);
606 }
607 /* if the guest wants write access, see if that is OK */
608 if (!writing && hpte_is_writable(r)) {
609 pte_t *ptep, pte;
610 unsigned long flags;
611 /*
612 * We need to protect against page table destruction
613 * hugepage split and collapse.
614 */
615 local_irq_save(flags);
616 ptep = find_current_mm_pte(current->mm->pgd,
617 hva, NULL, NULL);
618 if (ptep) {
619 pte = kvmppc_read_update_linux_pte(ptep, 1);
620 if (__pte_write(pte))
621 write_ok = 1;
622 }
623 local_irq_restore(flags);
624 }
625 }
626
627 if (psize > pte_size)
628 goto out_put;
629
630 /* Check WIMG vs. the actual page we're accessing */
631 if (!hpte_cache_flags_ok(r, is_ci)) {
632 if (is_ci)
633 goto out_put;
634 /*
635 * Allow guest to map emulated device memory as
636 * uncacheable, but actually make it cacheable.
637 */
638 r = (r & ~(HPTE_R_W|HPTE_R_I|HPTE_R_G)) | HPTE_R_M;
639 }
640
641 /*
642 * Set the HPTE to point to pfn.
643 * Since the pfn is at PAGE_SIZE granularity, make sure we
644 * don't mask out lower-order bits if psize < PAGE_SIZE.
645 */
646 if (psize < PAGE_SIZE)
647 psize = PAGE_SIZE;
648 r = (r & HPTE_R_KEY_HI) | (r & ~(HPTE_R_PP0 - psize)) |
649 ((pfn << PAGE_SHIFT) & ~(psize - 1));
650 if (hpte_is_writable(r) && !write_ok)
651 r = hpte_make_readonly(r);
652 ret = RESUME_GUEST;
653 preempt_disable();
654 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
655 cpu_relax();
656 hnow_v = be64_to_cpu(hptep[0]);
657 hnow_r = be64_to_cpu(hptep[1]);
658 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
659 hnow_v = hpte_new_to_old_v(hnow_v, hnow_r);
660 hnow_r = hpte_new_to_old_r(hnow_r);
661 }
662
663 /*
664 * If the HPT is being resized, don't update the HPTE,
665 * instead let the guest retry after the resize operation is complete.
666 * The synchronization for mmu_ready test vs. set is provided
667 * by the HPTE lock.
668 */
669 if (!kvm->arch.mmu_ready)
670 goto out_unlock;
671
672 if ((hnow_v & ~HPTE_V_HVLOCK) != hpte[0] || hnow_r != hpte[1] ||
673 rev->guest_rpte != hpte[2])
674 /* HPTE has been changed under us; let the guest retry */
675 goto out_unlock;
676 hpte[0] = (hpte[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID;
677
678 /* Always put the HPTE in the rmap chain for the page base address */
679 rmap = &memslot->arch.rmap[gfn_base - memslot->base_gfn];
680 lock_rmap(rmap);
681
682 /* Check if we might have been invalidated; let the guest retry if so */
683 ret = RESUME_GUEST;
684 if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) {
685 unlock_rmap(rmap);
686 goto out_unlock;
687 }
688
689 /* Only set R/C in real HPTE if set in both *rmap and guest_rpte */
690 rcbits = *rmap >> KVMPPC_RMAP_RC_SHIFT;
691 r &= rcbits | ~(HPTE_R_R | HPTE_R_C);
692
693 if (be64_to_cpu(hptep[0]) & HPTE_V_VALID) {
694 /* HPTE was previously valid, so we need to invalidate it */
695 unlock_rmap(rmap);
696 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
697 kvmppc_invalidate_hpte(kvm, hptep, index);
698 /* don't lose previous R and C bits */
699 r |= be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C);
700 } else {
701 kvmppc_add_revmap_chain(kvm, rev, rmap, index, 0);
702 }
703
704 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
705 r = hpte_old_to_new_r(hpte[0], r);
706 hpte[0] = hpte_old_to_new_v(hpte[0]);
707 }
708 hptep[1] = cpu_to_be64(r);
709 eieio();
710 __unlock_hpte(hptep, hpte[0]);
711 asm volatile("ptesync" : : : "memory");
712 preempt_enable();
713 if (page && hpte_is_writable(r))
714 SetPageDirty(page);
715
716 out_put:
717 trace_kvm_page_fault_exit(vcpu, hpte, ret);
718
719 if (page) {
720 /*
721 * We drop pages[0] here, not page because page might
722 * have been set to the head page of a compound, but
723 * we have to drop the reference on the correct tail
724 * page to match the get inside gup()
725 */
726 put_page(pages[0]);
727 }
728 return ret;
729
730 out_unlock:
731 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
732 preempt_enable();
733 goto out_put;
734 }
735
736 void kvmppc_rmap_reset(struct kvm *kvm)
737 {
738 struct kvm_memslots *slots;
739 struct kvm_memory_slot *memslot;
740 int srcu_idx;
741
742 srcu_idx = srcu_read_lock(&kvm->srcu);
743 slots = kvm_memslots(kvm);
744 kvm_for_each_memslot(memslot, slots) {
745 /*
746 * This assumes it is acceptable to lose reference and
747 * change bits across a reset.
748 */
749 memset(memslot->arch.rmap, 0,
750 memslot->npages * sizeof(*memslot->arch.rmap));
751 }
752 srcu_read_unlock(&kvm->srcu, srcu_idx);
753 }
754
755 typedef int (*hva_handler_fn)(struct kvm *kvm, struct kvm_memory_slot *memslot,
756 unsigned long gfn);
757
758 static int kvm_handle_hva_range(struct kvm *kvm,
759 unsigned long start,
760 unsigned long end,
761 hva_handler_fn handler)
762 {
763 int ret;
764 int retval = 0;
765 struct kvm_memslots *slots;
766 struct kvm_memory_slot *memslot;
767
768 slots = kvm_memslots(kvm);
769 kvm_for_each_memslot(memslot, slots) {
770 unsigned long hva_start, hva_end;
771 gfn_t gfn, gfn_end;
772
773 hva_start = max(start, memslot->userspace_addr);
774 hva_end = min(end, memslot->userspace_addr +
775 (memslot->npages << PAGE_SHIFT));
776 if (hva_start >= hva_end)
777 continue;
778 /*
779 * {gfn(page) | page intersects with [hva_start, hva_end)} =
780 * {gfn, gfn+1, ..., gfn_end-1}.
781 */
782 gfn = hva_to_gfn_memslot(hva_start, memslot);
783 gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);
784
785 for (; gfn < gfn_end; ++gfn) {
786 ret = handler(kvm, memslot, gfn);
787 retval |= ret;
788 }
789 }
790
791 return retval;
792 }
793
794 static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
795 hva_handler_fn handler)
796 {
797 return kvm_handle_hva_range(kvm, hva, hva + 1, handler);
798 }
799
800 /* Must be called with both HPTE and rmap locked */
801 static void kvmppc_unmap_hpte(struct kvm *kvm, unsigned long i,
802 struct kvm_memory_slot *memslot,
803 unsigned long *rmapp, unsigned long gfn)
804 {
805 __be64 *hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
806 struct revmap_entry *rev = kvm->arch.hpt.rev;
807 unsigned long j, h;
808 unsigned long ptel, psize, rcbits;
809
810 j = rev[i].forw;
811 if (j == i) {
812 /* chain is now empty */
813 *rmapp &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX);
814 } else {
815 /* remove i from chain */
816 h = rev[i].back;
817 rev[h].forw = j;
818 rev[j].back = h;
819 rev[i].forw = rev[i].back = i;
820 *rmapp = (*rmapp & ~KVMPPC_RMAP_INDEX) | j;
821 }
822
823 /* Now check and modify the HPTE */
824 ptel = rev[i].guest_rpte;
825 psize = kvmppc_actual_pgsz(be64_to_cpu(hptep[0]), ptel);
826 if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) &&
827 hpte_rpn(ptel, psize) == gfn) {
828 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
829 kvmppc_invalidate_hpte(kvm, hptep, i);
830 hptep[1] &= ~cpu_to_be64(HPTE_R_KEY_HI | HPTE_R_KEY_LO);
831 /* Harvest R and C */
832 rcbits = be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C);
833 *rmapp |= rcbits << KVMPPC_RMAP_RC_SHIFT;
834 if ((rcbits & HPTE_R_C) && memslot->dirty_bitmap)
835 kvmppc_update_dirty_map(memslot, gfn, psize);
836 if (rcbits & ~rev[i].guest_rpte) {
837 rev[i].guest_rpte = ptel | rcbits;
838 note_hpte_modification(kvm, &rev[i]);
839 }
840 }
841 }
842
843 static int kvm_unmap_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
844 unsigned long gfn)
845 {
846 unsigned long i;
847 __be64 *hptep;
848 unsigned long *rmapp;
849
850 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
851 for (;;) {
852 lock_rmap(rmapp);
853 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
854 unlock_rmap(rmapp);
855 break;
856 }
857
858 /*
859 * To avoid an ABBA deadlock with the HPTE lock bit,
860 * we can't spin on the HPTE lock while holding the
861 * rmap chain lock.
862 */
863 i = *rmapp & KVMPPC_RMAP_INDEX;
864 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
865 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
866 /* unlock rmap before spinning on the HPTE lock */
867 unlock_rmap(rmapp);
868 while (be64_to_cpu(hptep[0]) & HPTE_V_HVLOCK)
869 cpu_relax();
870 continue;
871 }
872
873 kvmppc_unmap_hpte(kvm, i, memslot, rmapp, gfn);
874 unlock_rmap(rmapp);
875 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
876 }
877 return 0;
878 }
879
880 int kvm_unmap_hva_hv(struct kvm *kvm, unsigned long hva)
881 {
882 hva_handler_fn handler;
883
884 handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
885 kvm_handle_hva(kvm, hva, handler);
886 return 0;
887 }
888
889 int kvm_unmap_hva_range_hv(struct kvm *kvm, unsigned long start, unsigned long end)
890 {
891 hva_handler_fn handler;
892
893 handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
894 kvm_handle_hva_range(kvm, start, end, handler);
895 return 0;
896 }
897
898 void kvmppc_core_flush_memslot_hv(struct kvm *kvm,
899 struct kvm_memory_slot *memslot)
900 {
901 unsigned long gfn;
902 unsigned long n;
903 unsigned long *rmapp;
904
905 gfn = memslot->base_gfn;
906 rmapp = memslot->arch.rmap;
907 for (n = memslot->npages; n; --n, ++gfn) {
908 if (kvm_is_radix(kvm)) {
909 kvm_unmap_radix(kvm, memslot, gfn);
910 continue;
911 }
912 /*
913 * Testing the present bit without locking is OK because
914 * the memslot has been marked invalid already, and hence
915 * no new HPTEs referencing this page can be created,
916 * thus the present bit can't go from 0 to 1.
917 */
918 if (*rmapp & KVMPPC_RMAP_PRESENT)
919 kvm_unmap_rmapp(kvm, memslot, gfn);
920 ++rmapp;
921 }
922 }
923
924 static int kvm_age_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
925 unsigned long gfn)
926 {
927 struct revmap_entry *rev = kvm->arch.hpt.rev;
928 unsigned long head, i, j;
929 __be64 *hptep;
930 int ret = 0;
931 unsigned long *rmapp;
932
933 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
934 retry:
935 lock_rmap(rmapp);
936 if (*rmapp & KVMPPC_RMAP_REFERENCED) {
937 *rmapp &= ~KVMPPC_RMAP_REFERENCED;
938 ret = 1;
939 }
940 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
941 unlock_rmap(rmapp);
942 return ret;
943 }
944
945 i = head = *rmapp & KVMPPC_RMAP_INDEX;
946 do {
947 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
948 j = rev[i].forw;
949
950 /* If this HPTE isn't referenced, ignore it */
951 if (!(be64_to_cpu(hptep[1]) & HPTE_R_R))
952 continue;
953
954 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
955 /* unlock rmap before spinning on the HPTE lock */
956 unlock_rmap(rmapp);
957 while (be64_to_cpu(hptep[0]) & HPTE_V_HVLOCK)
958 cpu_relax();
959 goto retry;
960 }
961
962 /* Now check and modify the HPTE */
963 if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) &&
964 (be64_to_cpu(hptep[1]) & HPTE_R_R)) {
965 kvmppc_clear_ref_hpte(kvm, hptep, i);
966 if (!(rev[i].guest_rpte & HPTE_R_R)) {
967 rev[i].guest_rpte |= HPTE_R_R;
968 note_hpte_modification(kvm, &rev[i]);
969 }
970 ret = 1;
971 }
972 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
973 } while ((i = j) != head);
974
975 unlock_rmap(rmapp);
976 return ret;
977 }
978
979 int kvm_age_hva_hv(struct kvm *kvm, unsigned long start, unsigned long end)
980 {
981 hva_handler_fn handler;
982
983 handler = kvm_is_radix(kvm) ? kvm_age_radix : kvm_age_rmapp;
984 return kvm_handle_hva_range(kvm, start, end, handler);
985 }
986
987 static int kvm_test_age_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
988 unsigned long gfn)
989 {
990 struct revmap_entry *rev = kvm->arch.hpt.rev;
991 unsigned long head, i, j;
992 unsigned long *hp;
993 int ret = 1;
994 unsigned long *rmapp;
995
996 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
997 if (*rmapp & KVMPPC_RMAP_REFERENCED)
998 return 1;
999
1000 lock_rmap(rmapp);
1001 if (*rmapp & KVMPPC_RMAP_REFERENCED)
1002 goto out;
1003
1004 if (*rmapp & KVMPPC_RMAP_PRESENT) {
1005 i = head = *rmapp & KVMPPC_RMAP_INDEX;
1006 do {
1007 hp = (unsigned long *)(kvm->arch.hpt.virt + (i << 4));
1008 j = rev[i].forw;
1009 if (be64_to_cpu(hp[1]) & HPTE_R_R)
1010 goto out;
1011 } while ((i = j) != head);
1012 }
1013 ret = 0;
1014
1015 out:
1016 unlock_rmap(rmapp);
1017 return ret;
1018 }
1019
1020 int kvm_test_age_hva_hv(struct kvm *kvm, unsigned long hva)
1021 {
1022 hva_handler_fn handler;
1023
1024 handler = kvm_is_radix(kvm) ? kvm_test_age_radix : kvm_test_age_rmapp;
1025 return kvm_handle_hva(kvm, hva, handler);
1026 }
1027
1028 void kvm_set_spte_hva_hv(struct kvm *kvm, unsigned long hva, pte_t pte)
1029 {
1030 hva_handler_fn handler;
1031
1032 handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
1033 kvm_handle_hva(kvm, hva, handler);
1034 }
1035
1036 static int vcpus_running(struct kvm *kvm)
1037 {
1038 return atomic_read(&kvm->arch.vcpus_running) != 0;
1039 }
1040
1041 /*
1042 * Returns the number of system pages that are dirty.
1043 * This can be more than 1 if we find a huge-page HPTE.
1044 */
1045 static int kvm_test_clear_dirty_npages(struct kvm *kvm, unsigned long *rmapp)
1046 {
1047 struct revmap_entry *rev = kvm->arch.hpt.rev;
1048 unsigned long head, i, j;
1049 unsigned long n;
1050 unsigned long v, r;
1051 __be64 *hptep;
1052 int npages_dirty = 0;
1053
1054 retry:
1055 lock_rmap(rmapp);
1056 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
1057 unlock_rmap(rmapp);
1058 return npages_dirty;
1059 }
1060
1061 i = head = *rmapp & KVMPPC_RMAP_INDEX;
1062 do {
1063 unsigned long hptep1;
1064 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
1065 j = rev[i].forw;
1066
1067 /*
1068 * Checking the C (changed) bit here is racy since there
1069 * is no guarantee about when the hardware writes it back.
1070 * If the HPTE is not writable then it is stable since the
1071 * page can't be written to, and we would have done a tlbie
1072 * (which forces the hardware to complete any writeback)
1073 * when making the HPTE read-only.
1074 * If vcpus are running then this call is racy anyway
1075 * since the page could get dirtied subsequently, so we
1076 * expect there to be a further call which would pick up
1077 * any delayed C bit writeback.
1078 * Otherwise we need to do the tlbie even if C==0 in
1079 * order to pick up any delayed writeback of C.
1080 */
1081 hptep1 = be64_to_cpu(hptep[1]);
1082 if (!(hptep1 & HPTE_R_C) &&
1083 (!hpte_is_writable(hptep1) || vcpus_running(kvm)))
1084 continue;
1085
1086 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
1087 /* unlock rmap before spinning on the HPTE lock */
1088 unlock_rmap(rmapp);
1089 while (hptep[0] & cpu_to_be64(HPTE_V_HVLOCK))
1090 cpu_relax();
1091 goto retry;
1092 }
1093
1094 /* Now check and modify the HPTE */
1095 if (!(hptep[0] & cpu_to_be64(HPTE_V_VALID))) {
1096 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
1097 continue;
1098 }
1099
1100 /* need to make it temporarily absent so C is stable */
1101 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
1102 kvmppc_invalidate_hpte(kvm, hptep, i);
1103 v = be64_to_cpu(hptep[0]);
1104 r = be64_to_cpu(hptep[1]);
1105 if (r & HPTE_R_C) {
1106 hptep[1] = cpu_to_be64(r & ~HPTE_R_C);
1107 if (!(rev[i].guest_rpte & HPTE_R_C)) {
1108 rev[i].guest_rpte |= HPTE_R_C;
1109 note_hpte_modification(kvm, &rev[i]);
1110 }
1111 n = kvmppc_actual_pgsz(v, r);
1112 n = (n + PAGE_SIZE - 1) >> PAGE_SHIFT;
1113 if (n > npages_dirty)
1114 npages_dirty = n;
1115 eieio();
1116 }
1117 v &= ~HPTE_V_ABSENT;
1118 v |= HPTE_V_VALID;
1119 __unlock_hpte(hptep, v);
1120 } while ((i = j) != head);
1121
1122 unlock_rmap(rmapp);
1123 return npages_dirty;
1124 }
1125
1126 void kvmppc_harvest_vpa_dirty(struct kvmppc_vpa *vpa,
1127 struct kvm_memory_slot *memslot,
1128 unsigned long *map)
1129 {
1130 unsigned long gfn;
1131
1132 if (!vpa->dirty || !vpa->pinned_addr)
1133 return;
1134 gfn = vpa->gpa >> PAGE_SHIFT;
1135 if (gfn < memslot->base_gfn ||
1136 gfn >= memslot->base_gfn + memslot->npages)
1137 return;
1138
1139 vpa->dirty = false;
1140 if (map)
1141 __set_bit_le(gfn - memslot->base_gfn, map);
1142 }
1143
1144 long kvmppc_hv_get_dirty_log_hpt(struct kvm *kvm,
1145 struct kvm_memory_slot *memslot, unsigned long *map)
1146 {
1147 unsigned long i;
1148 unsigned long *rmapp;
1149
1150 preempt_disable();
1151 rmapp = memslot->arch.rmap;
1152 for (i = 0; i < memslot->npages; ++i) {
1153 int npages = kvm_test_clear_dirty_npages(kvm, rmapp);
1154 /*
1155 * Note that if npages > 0 then i must be a multiple of npages,
1156 * since we always put huge-page HPTEs in the rmap chain
1157 * corresponding to their page base address.
1158 */
1159 if (npages)
1160 set_dirty_bits(map, i, npages);
1161 ++rmapp;
1162 }
1163 preempt_enable();
1164 return 0;
1165 }
1166
1167 void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
1168 unsigned long *nb_ret)
1169 {
1170 struct kvm_memory_slot *memslot;
1171 unsigned long gfn = gpa >> PAGE_SHIFT;
1172 struct page *page, *pages[1];
1173 int npages;
1174 unsigned long hva, offset;
1175 int srcu_idx;
1176
1177 srcu_idx = srcu_read_lock(&kvm->srcu);
1178 memslot = gfn_to_memslot(kvm, gfn);
1179 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
1180 goto err;
1181 hva = gfn_to_hva_memslot(memslot, gfn);
1182 npages = get_user_pages_fast(hva, 1, 1, pages);
1183 if (npages < 1)
1184 goto err;
1185 page = pages[0];
1186 srcu_read_unlock(&kvm->srcu, srcu_idx);
1187
1188 offset = gpa & (PAGE_SIZE - 1);
1189 if (nb_ret)
1190 *nb_ret = PAGE_SIZE - offset;
1191 return page_address(page) + offset;
1192
1193 err:
1194 srcu_read_unlock(&kvm->srcu, srcu_idx);
1195 return NULL;
1196 }
1197
1198 void kvmppc_unpin_guest_page(struct kvm *kvm, void *va, unsigned long gpa,
1199 bool dirty)
1200 {
1201 struct page *page = virt_to_page(va);
1202 struct kvm_memory_slot *memslot;
1203 unsigned long gfn;
1204 int srcu_idx;
1205
1206 put_page(page);
1207
1208 if (!dirty)
1209 return;
1210
1211 /* We need to mark this page dirty in the memslot dirty_bitmap, if any */
1212 gfn = gpa >> PAGE_SHIFT;
1213 srcu_idx = srcu_read_lock(&kvm->srcu);
1214 memslot = gfn_to_memslot(kvm, gfn);
1215 if (memslot && memslot->dirty_bitmap)
1216 set_bit_le(gfn - memslot->base_gfn, memslot->dirty_bitmap);
1217 srcu_read_unlock(&kvm->srcu, srcu_idx);
1218 }
1219
1220 /*
1221 * HPT resizing
1222 */
1223 static int resize_hpt_allocate(struct kvm_resize_hpt *resize)
1224 {
1225 int rc;
1226
1227 rc = kvmppc_allocate_hpt(&resize->hpt, resize->order);
1228 if (rc < 0)
1229 return rc;
1230
1231 resize_hpt_debug(resize, "resize_hpt_allocate(): HPT @ 0x%lx\n",
1232 resize->hpt.virt);
1233
1234 return 0;
1235 }
1236
1237 static unsigned long resize_hpt_rehash_hpte(struct kvm_resize_hpt *resize,
1238 unsigned long idx)
1239 {
1240 struct kvm *kvm = resize->kvm;
1241 struct kvm_hpt_info *old = &kvm->arch.hpt;
1242 struct kvm_hpt_info *new = &resize->hpt;
1243 unsigned long old_hash_mask = (1ULL << (old->order - 7)) - 1;
1244 unsigned long new_hash_mask = (1ULL << (new->order - 7)) - 1;
1245 __be64 *hptep, *new_hptep;
1246 unsigned long vpte, rpte, guest_rpte;
1247 int ret;
1248 struct revmap_entry *rev;
1249 unsigned long apsize, avpn, pteg, hash;
1250 unsigned long new_idx, new_pteg, replace_vpte;
1251 int pshift;
1252
1253 hptep = (__be64 *)(old->virt + (idx << 4));
1254
1255 /* Guest is stopped, so new HPTEs can't be added or faulted
1256 * in, only unmapped or altered by host actions. So, it's
1257 * safe to check this before we take the HPTE lock */
1258 vpte = be64_to_cpu(hptep[0]);
1259 if (!(vpte & HPTE_V_VALID) && !(vpte & HPTE_V_ABSENT))
1260 return 0; /* nothing to do */
1261
1262 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
1263 cpu_relax();
1264
1265 vpte = be64_to_cpu(hptep[0]);
1266
1267 ret = 0;
1268 if (!(vpte & HPTE_V_VALID) && !(vpte & HPTE_V_ABSENT))
1269 /* Nothing to do */
1270 goto out;
1271
1272 /* Unmap */
1273 rev = &old->rev[idx];
1274 guest_rpte = rev->guest_rpte;
1275
1276 ret = -EIO;
1277 apsize = kvmppc_actual_pgsz(vpte, guest_rpte);
1278 if (!apsize)
1279 goto out;
1280
1281 if (vpte & HPTE_V_VALID) {
1282 unsigned long gfn = hpte_rpn(guest_rpte, apsize);
1283 int srcu_idx = srcu_read_lock(&kvm->srcu);
1284 struct kvm_memory_slot *memslot =
1285 __gfn_to_memslot(kvm_memslots(kvm), gfn);
1286
1287 if (memslot) {
1288 unsigned long *rmapp;
1289 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1290
1291 lock_rmap(rmapp);
1292 kvmppc_unmap_hpte(kvm, idx, memslot, rmapp, gfn);
1293 unlock_rmap(rmapp);
1294 }
1295
1296 srcu_read_unlock(&kvm->srcu, srcu_idx);
1297 }
1298
1299 /* Reload PTE after unmap */
1300 vpte = be64_to_cpu(hptep[0]);
1301
1302 BUG_ON(vpte & HPTE_V_VALID);
1303 BUG_ON(!(vpte & HPTE_V_ABSENT));
1304
1305 ret = 0;
1306 if (!(vpte & HPTE_V_BOLTED))
1307 goto out;
1308
1309 rpte = be64_to_cpu(hptep[1]);
1310 pshift = kvmppc_hpte_base_page_shift(vpte, rpte);
1311 avpn = HPTE_V_AVPN_VAL(vpte) & ~(((1ul << pshift) - 1) >> 23);
1312 pteg = idx / HPTES_PER_GROUP;
1313 if (vpte & HPTE_V_SECONDARY)
1314 pteg = ~pteg;
1315
1316 if (!(vpte & HPTE_V_1TB_SEG)) {
1317 unsigned long offset, vsid;
1318
1319 /* We only have 28 - 23 bits of offset in avpn */
1320 offset = (avpn & 0x1f) << 23;
1321 vsid = avpn >> 5;
1322 /* We can find more bits from the pteg value */
1323 if (pshift < 23)
1324 offset |= ((vsid ^ pteg) & old_hash_mask) << pshift;
1325
1326 hash = vsid ^ (offset >> pshift);
1327 } else {
1328 unsigned long offset, vsid;
1329
1330 /* We only have 40 - 23 bits of seg_off in avpn */
1331 offset = (avpn & 0x1ffff) << 23;
1332 vsid = avpn >> 17;
1333 if (pshift < 23)
1334 offset |= ((vsid ^ (vsid << 25) ^ pteg) & old_hash_mask) << pshift;
1335
1336 hash = vsid ^ (vsid << 25) ^ (offset >> pshift);
1337 }
1338
1339 new_pteg = hash & new_hash_mask;
1340 if (vpte & HPTE_V_SECONDARY) {
1341 BUG_ON(~pteg != (hash & old_hash_mask));
1342 new_pteg = ~new_pteg;
1343 } else {
1344 BUG_ON(pteg != (hash & old_hash_mask));
1345 }
1346
1347 new_idx = new_pteg * HPTES_PER_GROUP + (idx % HPTES_PER_GROUP);
1348 new_hptep = (__be64 *)(new->virt + (new_idx << 4));
1349
1350 replace_vpte = be64_to_cpu(new_hptep[0]);
1351
1352 if (replace_vpte & (HPTE_V_VALID | HPTE_V_ABSENT)) {
1353 BUG_ON(new->order >= old->order);
1354
1355 if (replace_vpte & HPTE_V_BOLTED) {
1356 if (vpte & HPTE_V_BOLTED)
1357 /* Bolted collision, nothing we can do */
1358 ret = -ENOSPC;
1359 /* Discard the new HPTE */
1360 goto out;
1361 }
1362
1363 /* Discard the previous HPTE */
1364 }
1365
1366 new_hptep[1] = cpu_to_be64(rpte);
1367 new->rev[new_idx].guest_rpte = guest_rpte;
1368 /* No need for a barrier, since new HPT isn't active */
1369 new_hptep[0] = cpu_to_be64(vpte);
1370 unlock_hpte(new_hptep, vpte);
1371
1372 out:
1373 unlock_hpte(hptep, vpte);
1374 return ret;
1375 }
1376
1377 static int resize_hpt_rehash(struct kvm_resize_hpt *resize)
1378 {
1379 struct kvm *kvm = resize->kvm;
1380 unsigned long i;
1381 int rc;
1382
1383 /*
1384 * resize_hpt_rehash_hpte() doesn't handle the new-format HPTEs
1385 * that POWER9 uses, and could well hit a BUG_ON on POWER9.
1386 */
1387 if (cpu_has_feature(CPU_FTR_ARCH_300))
1388 return -EIO;
1389 for (i = 0; i < kvmppc_hpt_npte(&kvm->arch.hpt); i++) {
1390 rc = resize_hpt_rehash_hpte(resize, i);
1391 if (rc != 0)
1392 return rc;
1393 }
1394
1395 return 0;
1396 }
1397
1398 static void resize_hpt_pivot(struct kvm_resize_hpt *resize)
1399 {
1400 struct kvm *kvm = resize->kvm;
1401 struct kvm_hpt_info hpt_tmp;
1402
1403 /* Exchange the pending tables in the resize structure with
1404 * the active tables */
1405
1406 resize_hpt_debug(resize, "resize_hpt_pivot()\n");
1407
1408 spin_lock(&kvm->mmu_lock);
1409 asm volatile("ptesync" : : : "memory");
1410
1411 hpt_tmp = kvm->arch.hpt;
1412 kvmppc_set_hpt(kvm, &resize->hpt);
1413 resize->hpt = hpt_tmp;
1414
1415 spin_unlock(&kvm->mmu_lock);
1416
1417 synchronize_srcu_expedited(&kvm->srcu);
1418
1419 resize_hpt_debug(resize, "resize_hpt_pivot() done\n");
1420 }
1421
1422 static void resize_hpt_release(struct kvm *kvm, struct kvm_resize_hpt *resize)
1423 {
1424 if (WARN_ON(!mutex_is_locked(&kvm->lock)))
1425 return;
1426
1427 if (!resize)
1428 return;
1429
1430 if (resize->error != -EBUSY) {
1431 if (resize->hpt.virt)
1432 kvmppc_free_hpt(&resize->hpt);
1433 kfree(resize);
1434 }
1435
1436 if (kvm->arch.resize_hpt == resize)
1437 kvm->arch.resize_hpt = NULL;
1438 }
1439
1440 static void resize_hpt_prepare_work(struct work_struct *work)
1441 {
1442 struct kvm_resize_hpt *resize = container_of(work,
1443 struct kvm_resize_hpt,
1444 work);
1445 struct kvm *kvm = resize->kvm;
1446 int err = 0;
1447
1448 if (WARN_ON(resize->error != -EBUSY))
1449 return;
1450
1451 mutex_lock(&kvm->lock);
1452
1453 /* Request is still current? */
1454 if (kvm->arch.resize_hpt == resize) {
1455 /* We may request large allocations here:
1456 * do not sleep with kvm->lock held for a while.
1457 */
1458 mutex_unlock(&kvm->lock);
1459
1460 resize_hpt_debug(resize, "resize_hpt_prepare_work(): order = %d\n",
1461 resize->order);
1462
1463 err = resize_hpt_allocate(resize);
1464
1465 /* We have strict assumption about -EBUSY
1466 * when preparing for HPT resize.
1467 */
1468 if (WARN_ON(err == -EBUSY))
1469 err = -EINPROGRESS;
1470
1471 mutex_lock(&kvm->lock);
1472 /* It is possible that kvm->arch.resize_hpt != resize
1473 * after we grab kvm->lock again.
1474 */
1475 }
1476
1477 resize->error = err;
1478
1479 if (kvm->arch.resize_hpt != resize)
1480 resize_hpt_release(kvm, resize);
1481
1482 mutex_unlock(&kvm->lock);
1483 }
1484
1485 long kvm_vm_ioctl_resize_hpt_prepare(struct kvm *kvm,
1486 struct kvm_ppc_resize_hpt *rhpt)
1487 {
1488 unsigned long flags = rhpt->flags;
1489 unsigned long shift = rhpt->shift;
1490 struct kvm_resize_hpt *resize;
1491 int ret;
1492
1493 if (flags != 0 || kvm_is_radix(kvm))
1494 return -EINVAL;
1495
1496 if (shift && ((shift < 18) || (shift > 46)))
1497 return -EINVAL;
1498
1499 mutex_lock(&kvm->lock);
1500
1501 resize = kvm->arch.resize_hpt;
1502
1503 if (resize) {
1504 if (resize->order == shift) {
1505 /* Suitable resize in progress? */
1506 ret = resize->error;
1507 if (ret == -EBUSY)
1508 ret = 100; /* estimated time in ms */
1509 else if (ret)
1510 resize_hpt_release(kvm, resize);
1511
1512 goto out;
1513 }
1514
1515 /* not suitable, cancel it */
1516 resize_hpt_release(kvm, resize);
1517 }
1518
1519 ret = 0;
1520 if (!shift)
1521 goto out; /* nothing to do */
1522
1523 /* start new resize */
1524
1525 resize = kzalloc(sizeof(*resize), GFP_KERNEL);
1526 if (!resize) {
1527 ret = -ENOMEM;
1528 goto out;
1529 }
1530
1531 resize->error = -EBUSY;
1532 resize->order = shift;
1533 resize->kvm = kvm;
1534 INIT_WORK(&resize->work, resize_hpt_prepare_work);
1535 kvm->arch.resize_hpt = resize;
1536
1537 schedule_work(&resize->work);
1538
1539 ret = 100; /* estimated time in ms */
1540
1541 out:
1542 mutex_unlock(&kvm->lock);
1543 return ret;
1544 }
1545
1546 static void resize_hpt_boot_vcpu(void *opaque)
1547 {
1548 /* Nothing to do, just force a KVM exit */
1549 }
1550
1551 long kvm_vm_ioctl_resize_hpt_commit(struct kvm *kvm,
1552 struct kvm_ppc_resize_hpt *rhpt)
1553 {
1554 unsigned long flags = rhpt->flags;
1555 unsigned long shift = rhpt->shift;
1556 struct kvm_resize_hpt *resize;
1557 long ret;
1558
1559 if (flags != 0 || kvm_is_radix(kvm))
1560 return -EINVAL;
1561
1562 if (shift && ((shift < 18) || (shift > 46)))
1563 return -EINVAL;
1564
1565 mutex_lock(&kvm->lock);
1566
1567 resize = kvm->arch.resize_hpt;
1568
1569 /* This shouldn't be possible */
1570 ret = -EIO;
1571 if (WARN_ON(!kvm->arch.mmu_ready))
1572 goto out_no_hpt;
1573
1574 /* Stop VCPUs from running while we mess with the HPT */
1575 kvm->arch.mmu_ready = 0;
1576 smp_mb();
1577
1578 /* Boot all CPUs out of the guest so they re-read
1579 * mmu_ready */
1580 on_each_cpu(resize_hpt_boot_vcpu, NULL, 1);
1581
1582 ret = -ENXIO;
1583 if (!resize || (resize->order != shift))
1584 goto out;
1585
1586 ret = resize->error;
1587 if (ret)
1588 goto out;
1589
1590 ret = resize_hpt_rehash(resize);
1591 if (ret)
1592 goto out;
1593
1594 resize_hpt_pivot(resize);
1595
1596 out:
1597 /* Let VCPUs run again */
1598 kvm->arch.mmu_ready = 1;
1599 smp_mb();
1600 out_no_hpt:
1601 resize_hpt_release(kvm, resize);
1602 mutex_unlock(&kvm->lock);
1603 return ret;
1604 }
1605
1606 /*
1607 * Functions for reading and writing the hash table via reads and
1608 * writes on a file descriptor.
1609 *
1610 * Reads return the guest view of the hash table, which has to be
1611 * pieced together from the real hash table and the guest_rpte
1612 * values in the revmap array.
1613 *
1614 * On writes, each HPTE written is considered in turn, and if it
1615 * is valid, it is written to the HPT as if an H_ENTER with the
1616 * exact flag set was done. When the invalid count is non-zero
1617 * in the header written to the stream, the kernel will make
1618 * sure that that many HPTEs are invalid, and invalidate them
1619 * if not.
1620 */
1621
1622 struct kvm_htab_ctx {
1623 unsigned long index;
1624 unsigned long flags;
1625 struct kvm *kvm;
1626 int first_pass;
1627 };
1628
1629 #define HPTE_SIZE (2 * sizeof(unsigned long))
1630
1631 /*
1632 * Returns 1 if this HPT entry has been modified or has pending
1633 * R/C bit changes.
1634 */
1635 static int hpte_dirty(struct revmap_entry *revp, __be64 *hptp)
1636 {
1637 unsigned long rcbits_unset;
1638
1639 if (revp->guest_rpte & HPTE_GR_MODIFIED)
1640 return 1;
1641
1642 /* Also need to consider changes in reference and changed bits */
1643 rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C);
1644 if ((be64_to_cpu(hptp[0]) & HPTE_V_VALID) &&
1645 (be64_to_cpu(hptp[1]) & rcbits_unset))
1646 return 1;
1647
1648 return 0;
1649 }
1650
1651 static long record_hpte(unsigned long flags, __be64 *hptp,
1652 unsigned long *hpte, struct revmap_entry *revp,
1653 int want_valid, int first_pass)
1654 {
1655 unsigned long v, r, hr;
1656 unsigned long rcbits_unset;
1657 int ok = 1;
1658 int valid, dirty;
1659
1660 /* Unmodified entries are uninteresting except on the first pass */
1661 dirty = hpte_dirty(revp, hptp);
1662 if (!first_pass && !dirty)
1663 return 0;
1664
1665 valid = 0;
1666 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)) {
1667 valid = 1;
1668 if ((flags & KVM_GET_HTAB_BOLTED_ONLY) &&
1669 !(be64_to_cpu(hptp[0]) & HPTE_V_BOLTED))
1670 valid = 0;
1671 }
1672 if (valid != want_valid)
1673 return 0;
1674
1675 v = r = 0;
1676 if (valid || dirty) {
1677 /* lock the HPTE so it's stable and read it */
1678 preempt_disable();
1679 while (!try_lock_hpte(hptp, HPTE_V_HVLOCK))
1680 cpu_relax();
1681 v = be64_to_cpu(hptp[0]);
1682 hr = be64_to_cpu(hptp[1]);
1683 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1684 v = hpte_new_to_old_v(v, hr);
1685 hr = hpte_new_to_old_r(hr);
1686 }
1687
1688 /* re-evaluate valid and dirty from synchronized HPTE value */
1689 valid = !!(v & HPTE_V_VALID);
1690 dirty = !!(revp->guest_rpte & HPTE_GR_MODIFIED);
1691
1692 /* Harvest R and C into guest view if necessary */
1693 rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C);
1694 if (valid && (rcbits_unset & hr)) {
1695 revp->guest_rpte |= (hr &
1696 (HPTE_R_R | HPTE_R_C)) | HPTE_GR_MODIFIED;
1697 dirty = 1;
1698 }
1699
1700 if (v & HPTE_V_ABSENT) {
1701 v &= ~HPTE_V_ABSENT;
1702 v |= HPTE_V_VALID;
1703 valid = 1;
1704 }
1705 if ((flags & KVM_GET_HTAB_BOLTED_ONLY) && !(v & HPTE_V_BOLTED))
1706 valid = 0;
1707
1708 r = revp->guest_rpte;
1709 /* only clear modified if this is the right sort of entry */
1710 if (valid == want_valid && dirty) {
1711 r &= ~HPTE_GR_MODIFIED;
1712 revp->guest_rpte = r;
1713 }
1714 unlock_hpte(hptp, be64_to_cpu(hptp[0]));
1715 preempt_enable();
1716 if (!(valid == want_valid && (first_pass || dirty)))
1717 ok = 0;
1718 }
1719 hpte[0] = cpu_to_be64(v);
1720 hpte[1] = cpu_to_be64(r);
1721 return ok;
1722 }
1723
1724 static ssize_t kvm_htab_read(struct file *file, char __user *buf,
1725 size_t count, loff_t *ppos)
1726 {
1727 struct kvm_htab_ctx *ctx = file->private_data;
1728 struct kvm *kvm = ctx->kvm;
1729 struct kvm_get_htab_header hdr;
1730 __be64 *hptp;
1731 struct revmap_entry *revp;
1732 unsigned long i, nb, nw;
1733 unsigned long __user *lbuf;
1734 struct kvm_get_htab_header __user *hptr;
1735 unsigned long flags;
1736 int first_pass;
1737 unsigned long hpte[2];
1738
1739 if (!access_ok(VERIFY_WRITE, buf, count))
1740 return -EFAULT;
1741 if (kvm_is_radix(kvm))
1742 return 0;
1743
1744 first_pass = ctx->first_pass;
1745 flags = ctx->flags;
1746
1747 i = ctx->index;
1748 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
1749 revp = kvm->arch.hpt.rev + i;
1750 lbuf = (unsigned long __user *)buf;
1751
1752 nb = 0;
1753 while (nb + sizeof(hdr) + HPTE_SIZE < count) {
1754 /* Initialize header */
1755 hptr = (struct kvm_get_htab_header __user *)buf;
1756 hdr.n_valid = 0;
1757 hdr.n_invalid = 0;
1758 nw = nb;
1759 nb += sizeof(hdr);
1760 lbuf = (unsigned long __user *)(buf + sizeof(hdr));
1761
1762 /* Skip uninteresting entries, i.e. clean on not-first pass */
1763 if (!first_pass) {
1764 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1765 !hpte_dirty(revp, hptp)) {
1766 ++i;
1767 hptp += 2;
1768 ++revp;
1769 }
1770 }
1771 hdr.index = i;
1772
1773 /* Grab a series of valid entries */
1774 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1775 hdr.n_valid < 0xffff &&
1776 nb + HPTE_SIZE < count &&
1777 record_hpte(flags, hptp, hpte, revp, 1, first_pass)) {
1778 /* valid entry, write it out */
1779 ++hdr.n_valid;
1780 if (__put_user(hpte[0], lbuf) ||
1781 __put_user(hpte[1], lbuf + 1))
1782 return -EFAULT;
1783 nb += HPTE_SIZE;
1784 lbuf += 2;
1785 ++i;
1786 hptp += 2;
1787 ++revp;
1788 }
1789 /* Now skip invalid entries while we can */
1790 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1791 hdr.n_invalid < 0xffff &&
1792 record_hpte(flags, hptp, hpte, revp, 0, first_pass)) {
1793 /* found an invalid entry */
1794 ++hdr.n_invalid;
1795 ++i;
1796 hptp += 2;
1797 ++revp;
1798 }
1799
1800 if (hdr.n_valid || hdr.n_invalid) {
1801 /* write back the header */
1802 if (__copy_to_user(hptr, &hdr, sizeof(hdr)))
1803 return -EFAULT;
1804 nw = nb;
1805 buf = (char __user *)lbuf;
1806 } else {
1807 nb = nw;
1808 }
1809
1810 /* Check if we've wrapped around the hash table */
1811 if (i >= kvmppc_hpt_npte(&kvm->arch.hpt)) {
1812 i = 0;
1813 ctx->first_pass = 0;
1814 break;
1815 }
1816 }
1817
1818 ctx->index = i;
1819
1820 return nb;
1821 }
1822
1823 static ssize_t kvm_htab_write(struct file *file, const char __user *buf,
1824 size_t count, loff_t *ppos)
1825 {
1826 struct kvm_htab_ctx *ctx = file->private_data;
1827 struct kvm *kvm = ctx->kvm;
1828 struct kvm_get_htab_header hdr;
1829 unsigned long i, j;
1830 unsigned long v, r;
1831 unsigned long __user *lbuf;
1832 __be64 *hptp;
1833 unsigned long tmp[2];
1834 ssize_t nb;
1835 long int err, ret;
1836 int mmu_ready;
1837 int pshift;
1838
1839 if (!access_ok(VERIFY_READ, buf, count))
1840 return -EFAULT;
1841 if (kvm_is_radix(kvm))
1842 return -EINVAL;
1843
1844 /* lock out vcpus from running while we're doing this */
1845 mutex_lock(&kvm->lock);
1846 mmu_ready = kvm->arch.mmu_ready;
1847 if (mmu_ready) {
1848 kvm->arch.mmu_ready = 0; /* temporarily */
1849 /* order mmu_ready vs. vcpus_running */
1850 smp_mb();
1851 if (atomic_read(&kvm->arch.vcpus_running)) {
1852 kvm->arch.mmu_ready = 1;
1853 mutex_unlock(&kvm->lock);
1854 return -EBUSY;
1855 }
1856 }
1857
1858 err = 0;
1859 for (nb = 0; nb + sizeof(hdr) <= count; ) {
1860 err = -EFAULT;
1861 if (__copy_from_user(&hdr, buf, sizeof(hdr)))
1862 break;
1863
1864 err = 0;
1865 if (nb + hdr.n_valid * HPTE_SIZE > count)
1866 break;
1867
1868 nb += sizeof(hdr);
1869 buf += sizeof(hdr);
1870
1871 err = -EINVAL;
1872 i = hdr.index;
1873 if (i >= kvmppc_hpt_npte(&kvm->arch.hpt) ||
1874 i + hdr.n_valid + hdr.n_invalid > kvmppc_hpt_npte(&kvm->arch.hpt))
1875 break;
1876
1877 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
1878 lbuf = (unsigned long __user *)buf;
1879 for (j = 0; j < hdr.n_valid; ++j) {
1880 __be64 hpte_v;
1881 __be64 hpte_r;
1882
1883 err = -EFAULT;
1884 if (__get_user(hpte_v, lbuf) ||
1885 __get_user(hpte_r, lbuf + 1))
1886 goto out;
1887 v = be64_to_cpu(hpte_v);
1888 r = be64_to_cpu(hpte_r);
1889 err = -EINVAL;
1890 if (!(v & HPTE_V_VALID))
1891 goto out;
1892 pshift = kvmppc_hpte_base_page_shift(v, r);
1893 if (pshift <= 0)
1894 goto out;
1895 lbuf += 2;
1896 nb += HPTE_SIZE;
1897
1898 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT))
1899 kvmppc_do_h_remove(kvm, 0, i, 0, tmp);
1900 err = -EIO;
1901 ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, i, v, r,
1902 tmp);
1903 if (ret != H_SUCCESS) {
1904 pr_err("kvm_htab_write ret %ld i=%ld v=%lx "
1905 "r=%lx\n", ret, i, v, r);
1906 goto out;
1907 }
1908 if (!mmu_ready && is_vrma_hpte(v)) {
1909 unsigned long senc, lpcr;
1910
1911 senc = slb_pgsize_encoding(1ul << pshift);
1912 kvm->arch.vrma_slb_v = senc | SLB_VSID_B_1T |
1913 (VRMA_VSID << SLB_VSID_SHIFT_1T);
1914 if (!cpu_has_feature(CPU_FTR_ARCH_300)) {
1915 lpcr = senc << (LPCR_VRMASD_SH - 4);
1916 kvmppc_update_lpcr(kvm, lpcr,
1917 LPCR_VRMASD);
1918 } else {
1919 kvmppc_setup_partition_table(kvm);
1920 }
1921 mmu_ready = 1;
1922 }
1923 ++i;
1924 hptp += 2;
1925 }
1926
1927 for (j = 0; j < hdr.n_invalid; ++j) {
1928 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT))
1929 kvmppc_do_h_remove(kvm, 0, i, 0, tmp);
1930 ++i;
1931 hptp += 2;
1932 }
1933 err = 0;
1934 }
1935
1936 out:
1937 /* Order HPTE updates vs. mmu_ready */
1938 smp_wmb();
1939 kvm->arch.mmu_ready = mmu_ready;
1940 mutex_unlock(&kvm->lock);
1941
1942 if (err)
1943 return err;
1944 return nb;
1945 }
1946
1947 static int kvm_htab_release(struct inode *inode, struct file *filp)
1948 {
1949 struct kvm_htab_ctx *ctx = filp->private_data;
1950
1951 filp->private_data = NULL;
1952 if (!(ctx->flags & KVM_GET_HTAB_WRITE))
1953 atomic_dec(&ctx->kvm->arch.hpte_mod_interest);
1954 kvm_put_kvm(ctx->kvm);
1955 kfree(ctx);
1956 return 0;
1957 }
1958
1959 static const struct file_operations kvm_htab_fops = {
1960 .read = kvm_htab_read,
1961 .write = kvm_htab_write,
1962 .llseek = default_llseek,
1963 .release = kvm_htab_release,
1964 };
1965
1966 int kvm_vm_ioctl_get_htab_fd(struct kvm *kvm, struct kvm_get_htab_fd *ghf)
1967 {
1968 int ret;
1969 struct kvm_htab_ctx *ctx;
1970 int rwflag;
1971
1972 /* reject flags we don't recognize */
1973 if (ghf->flags & ~(KVM_GET_HTAB_BOLTED_ONLY | KVM_GET_HTAB_WRITE))
1974 return -EINVAL;
1975 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1976 if (!ctx)
1977 return -ENOMEM;
1978 kvm_get_kvm(kvm);
1979 ctx->kvm = kvm;
1980 ctx->index = ghf->start_index;
1981 ctx->flags = ghf->flags;
1982 ctx->first_pass = 1;
1983
1984 rwflag = (ghf->flags & KVM_GET_HTAB_WRITE) ? O_WRONLY : O_RDONLY;
1985 ret = anon_inode_getfd("kvm-htab", &kvm_htab_fops, ctx, rwflag | O_CLOEXEC);
1986 if (ret < 0) {
1987 kfree(ctx);
1988 kvm_put_kvm(kvm);
1989 return ret;
1990 }
1991
1992 if (rwflag == O_RDONLY) {
1993 mutex_lock(&kvm->slots_lock);
1994 atomic_inc(&kvm->arch.hpte_mod_interest);
1995 /* make sure kvmppc_do_h_enter etc. see the increment */
1996 synchronize_srcu_expedited(&kvm->srcu);
1997 mutex_unlock(&kvm->slots_lock);
1998 }
1999
2000 return ret;
2001 }
2002
2003 struct debugfs_htab_state {
2004 struct kvm *kvm;
2005 struct mutex mutex;
2006 unsigned long hpt_index;
2007 int chars_left;
2008 int buf_index;
2009 char buf[64];
2010 };
2011
2012 static int debugfs_htab_open(struct inode *inode, struct file *file)
2013 {
2014 struct kvm *kvm = inode->i_private;
2015 struct debugfs_htab_state *p;
2016
2017 p = kzalloc(sizeof(*p), GFP_KERNEL);
2018 if (!p)
2019 return -ENOMEM;
2020
2021 kvm_get_kvm(kvm);
2022 p->kvm = kvm;
2023 mutex_init(&p->mutex);
2024 file->private_data = p;
2025
2026 return nonseekable_open(inode, file);
2027 }
2028
2029 static int debugfs_htab_release(struct inode *inode, struct file *file)
2030 {
2031 struct debugfs_htab_state *p = file->private_data;
2032
2033 kvm_put_kvm(p->kvm);
2034 kfree(p);
2035 return 0;
2036 }
2037
2038 static ssize_t debugfs_htab_read(struct file *file, char __user *buf,
2039 size_t len, loff_t *ppos)
2040 {
2041 struct debugfs_htab_state *p = file->private_data;
2042 ssize_t ret, r;
2043 unsigned long i, n;
2044 unsigned long v, hr, gr;
2045 struct kvm *kvm;
2046 __be64 *hptp;
2047
2048 kvm = p->kvm;
2049 if (kvm_is_radix(kvm))
2050 return 0;
2051
2052 ret = mutex_lock_interruptible(&p->mutex);
2053 if (ret)
2054 return ret;
2055
2056 if (p->chars_left) {
2057 n = p->chars_left;
2058 if (n > len)
2059 n = len;
2060 r = copy_to_user(buf, p->buf + p->buf_index, n);
2061 n -= r;
2062 p->chars_left -= n;
2063 p->buf_index += n;
2064 buf += n;
2065 len -= n;
2066 ret = n;
2067 if (r) {
2068 if (!n)
2069 ret = -EFAULT;
2070 goto out;
2071 }
2072 }
2073
2074 i = p->hpt_index;
2075 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
2076 for (; len != 0 && i < kvmppc_hpt_npte(&kvm->arch.hpt);
2077 ++i, hptp += 2) {
2078 if (!(be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)))
2079 continue;
2080
2081 /* lock the HPTE so it's stable and read it */
2082 preempt_disable();
2083 while (!try_lock_hpte(hptp, HPTE_V_HVLOCK))
2084 cpu_relax();
2085 v = be64_to_cpu(hptp[0]) & ~HPTE_V_HVLOCK;
2086 hr = be64_to_cpu(hptp[1]);
2087 gr = kvm->arch.hpt.rev[i].guest_rpte;
2088 unlock_hpte(hptp, v);
2089 preempt_enable();
2090
2091 if (!(v & (HPTE_V_VALID | HPTE_V_ABSENT)))
2092 continue;
2093
2094 n = scnprintf(p->buf, sizeof(p->buf),
2095 "%6lx %.16lx %.16lx %.16lx\n",
2096 i, v, hr, gr);
2097 p->chars_left = n;
2098 if (n > len)
2099 n = len;
2100 r = copy_to_user(buf, p->buf, n);
2101 n -= r;
2102 p->chars_left -= n;
2103 p->buf_index = n;
2104 buf += n;
2105 len -= n;
2106 ret += n;
2107 if (r) {
2108 if (!ret)
2109 ret = -EFAULT;
2110 goto out;
2111 }
2112 }
2113 p->hpt_index = i;
2114
2115 out:
2116 mutex_unlock(&p->mutex);
2117 return ret;
2118 }
2119
2120 static ssize_t debugfs_htab_write(struct file *file, const char __user *buf,
2121 size_t len, loff_t *ppos)
2122 {
2123 return -EACCES;
2124 }
2125
2126 static const struct file_operations debugfs_htab_fops = {
2127 .owner = THIS_MODULE,
2128 .open = debugfs_htab_open,
2129 .release = debugfs_htab_release,
2130 .read = debugfs_htab_read,
2131 .write = debugfs_htab_write,
2132 .llseek = generic_file_llseek,
2133 };
2134
2135 void kvmppc_mmu_debugfs_init(struct kvm *kvm)
2136 {
2137 kvm->arch.htab_dentry = debugfs_create_file("htab", 0400,
2138 kvm->arch.debugfs_dir, kvm,
2139 &debugfs_htab_fops);
2140 }
2141
2142 void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu)
2143 {
2144 struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
2145
2146 vcpu->arch.slb_nr = 32; /* POWER7/POWER8 */
2147
2148 mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate;
2149 mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr;
2150
2151 vcpu->arch.hflags |= BOOK3S_HFLAG_SLB;
2152 }
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