forked from Minki/linux
a92bce95f0
This reworks the implementations of the H_REMOVE and H_BULK_REMOVE hcalls to make sure that we keep the HPTE locked and in the reverse- mapping chain until we have finished invalidating it. Previously we would remove it from the chain and unlock it before invalidating it, leaving a tiny window when the guest could access the page even though we believe we have removed it from the guest (e.g., kvm_unmap_hva() has been called for the page and has found no HPTEs in the chain). In addition, we'll need this for future patches where we will need to read the R and C bits in the HPTE after invalidating it. Doing this required restructuring kvmppc_h_bulk_remove() substantially. Since we want to batch up the tlbies, we now need to keep several HPTEs locked simultaneously. In order to avoid possible deadlocks, we don't spin on the HPTE bitlock for any except the first HPTE in a batch. If we can't acquire the HPTE bitlock for the second or subsequent HPTE, we terminate the batch at that point, do the tlbies that we have accumulated so far, unlock those HPTEs, and then start a new batch to do the remaining invalidations. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
810 lines
22 KiB
C
810 lines
22 KiB
C
/*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License, version 2, as
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* published by the Free Software Foundation.
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*
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* Copyright 2010-2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
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*/
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#include <linux/types.h>
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#include <linux/string.h>
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#include <linux/kvm.h>
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#include <linux/kvm_host.h>
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#include <linux/hugetlb.h>
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#include <linux/module.h>
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#include <asm/tlbflush.h>
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#include <asm/kvm_ppc.h>
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#include <asm/kvm_book3s.h>
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#include <asm/mmu-hash64.h>
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#include <asm/hvcall.h>
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#include <asm/synch.h>
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#include <asm/ppc-opcode.h>
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/*
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* Since this file is built in even if KVM is a module, we need
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* a local copy of this function for the case where kvm_main.c is
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* modular.
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*/
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static struct kvm_memory_slot *builtin_gfn_to_memslot(struct kvm *kvm,
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gfn_t gfn)
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{
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struct kvm_memslots *slots;
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struct kvm_memory_slot *memslot;
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slots = kvm_memslots(kvm);
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kvm_for_each_memslot(memslot, slots)
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if (gfn >= memslot->base_gfn &&
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gfn < memslot->base_gfn + memslot->npages)
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return memslot;
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return NULL;
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}
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/* Translate address of a vmalloc'd thing to a linear map address */
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static void *real_vmalloc_addr(void *x)
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{
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unsigned long addr = (unsigned long) x;
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pte_t *p;
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p = find_linux_pte(swapper_pg_dir, addr);
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if (!p || !pte_present(*p))
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return NULL;
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/* assume we don't have huge pages in vmalloc space... */
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addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & ~PAGE_MASK);
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return __va(addr);
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}
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/*
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* Add this HPTE into the chain for the real page.
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* Must be called with the chain locked; it unlocks the chain.
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*/
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void kvmppc_add_revmap_chain(struct kvm *kvm, struct revmap_entry *rev,
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unsigned long *rmap, long pte_index, int realmode)
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{
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struct revmap_entry *head, *tail;
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unsigned long i;
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if (*rmap & KVMPPC_RMAP_PRESENT) {
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i = *rmap & KVMPPC_RMAP_INDEX;
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head = &kvm->arch.revmap[i];
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if (realmode)
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head = real_vmalloc_addr(head);
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tail = &kvm->arch.revmap[head->back];
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if (realmode)
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tail = real_vmalloc_addr(tail);
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rev->forw = i;
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rev->back = head->back;
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tail->forw = pte_index;
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head->back = pte_index;
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} else {
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rev->forw = rev->back = pte_index;
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i = pte_index;
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}
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smp_wmb();
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*rmap = i | KVMPPC_RMAP_REFERENCED | KVMPPC_RMAP_PRESENT; /* unlock */
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}
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EXPORT_SYMBOL_GPL(kvmppc_add_revmap_chain);
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/* Remove this HPTE from the chain for a real page */
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static void remove_revmap_chain(struct kvm *kvm, long pte_index,
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unsigned long hpte_v)
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{
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struct revmap_entry *rev, *next, *prev;
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unsigned long gfn, ptel, head;
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struct kvm_memory_slot *memslot;
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unsigned long *rmap;
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rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
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ptel = rev->guest_rpte;
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gfn = hpte_rpn(ptel, hpte_page_size(hpte_v, ptel));
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memslot = builtin_gfn_to_memslot(kvm, gfn);
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if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
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return;
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rmap = real_vmalloc_addr(&memslot->rmap[gfn - memslot->base_gfn]);
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lock_rmap(rmap);
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head = *rmap & KVMPPC_RMAP_INDEX;
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next = real_vmalloc_addr(&kvm->arch.revmap[rev->forw]);
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prev = real_vmalloc_addr(&kvm->arch.revmap[rev->back]);
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next->back = rev->back;
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prev->forw = rev->forw;
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if (head == pte_index) {
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head = rev->forw;
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if (head == pte_index)
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*rmap &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX);
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else
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*rmap = (*rmap & ~KVMPPC_RMAP_INDEX) | head;
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}
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unlock_rmap(rmap);
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}
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static pte_t lookup_linux_pte(struct kvm_vcpu *vcpu, unsigned long hva,
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int writing, unsigned long *pte_sizep)
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{
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pte_t *ptep;
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unsigned long ps = *pte_sizep;
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unsigned int shift;
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ptep = find_linux_pte_or_hugepte(vcpu->arch.pgdir, hva, &shift);
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if (!ptep)
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return __pte(0);
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if (shift)
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*pte_sizep = 1ul << shift;
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else
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*pte_sizep = PAGE_SIZE;
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if (ps > *pte_sizep)
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return __pte(0);
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if (!pte_present(*ptep))
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return __pte(0);
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return kvmppc_read_update_linux_pte(ptep, writing);
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}
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static inline void unlock_hpte(unsigned long *hpte, unsigned long hpte_v)
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{
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asm volatile(PPC_RELEASE_BARRIER "" : : : "memory");
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hpte[0] = hpte_v;
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}
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long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
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long pte_index, unsigned long pteh, unsigned long ptel)
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{
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struct kvm *kvm = vcpu->kvm;
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unsigned long i, pa, gpa, gfn, psize;
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unsigned long slot_fn, hva;
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unsigned long *hpte;
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struct revmap_entry *rev;
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unsigned long g_ptel = ptel;
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struct kvm_memory_slot *memslot;
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unsigned long *physp, pte_size;
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unsigned long is_io;
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unsigned long *rmap;
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pte_t pte;
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unsigned int writing;
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unsigned long mmu_seq;
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bool realmode = vcpu->arch.vcore->vcore_state == VCORE_RUNNING;
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psize = hpte_page_size(pteh, ptel);
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if (!psize)
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return H_PARAMETER;
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writing = hpte_is_writable(ptel);
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pteh &= ~(HPTE_V_HVLOCK | HPTE_V_ABSENT | HPTE_V_VALID);
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/* used later to detect if we might have been invalidated */
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mmu_seq = kvm->mmu_notifier_seq;
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smp_rmb();
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/* Find the memslot (if any) for this address */
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gpa = (ptel & HPTE_R_RPN) & ~(psize - 1);
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gfn = gpa >> PAGE_SHIFT;
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memslot = builtin_gfn_to_memslot(kvm, gfn);
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pa = 0;
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is_io = ~0ul;
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rmap = NULL;
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if (!(memslot && !(memslot->flags & KVM_MEMSLOT_INVALID))) {
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/* PPC970 can't do emulated MMIO */
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if (!cpu_has_feature(CPU_FTR_ARCH_206))
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return H_PARAMETER;
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/* Emulated MMIO - mark this with key=31 */
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pteh |= HPTE_V_ABSENT;
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ptel |= HPTE_R_KEY_HI | HPTE_R_KEY_LO;
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goto do_insert;
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}
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/* Check if the requested page fits entirely in the memslot. */
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if (!slot_is_aligned(memslot, psize))
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return H_PARAMETER;
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slot_fn = gfn - memslot->base_gfn;
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rmap = &memslot->rmap[slot_fn];
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if (!kvm->arch.using_mmu_notifiers) {
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physp = kvm->arch.slot_phys[memslot->id];
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if (!physp)
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return H_PARAMETER;
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physp += slot_fn;
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if (realmode)
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physp = real_vmalloc_addr(physp);
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pa = *physp;
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if (!pa)
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return H_TOO_HARD;
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is_io = pa & (HPTE_R_I | HPTE_R_W);
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pte_size = PAGE_SIZE << (pa & KVMPPC_PAGE_ORDER_MASK);
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pa &= PAGE_MASK;
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} else {
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/* Translate to host virtual address */
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hva = gfn_to_hva_memslot(memslot, gfn);
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/* Look up the Linux PTE for the backing page */
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pte_size = psize;
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pte = lookup_linux_pte(vcpu, hva, writing, &pte_size);
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if (pte_present(pte)) {
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if (writing && !pte_write(pte))
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/* make the actual HPTE be read-only */
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ptel = hpte_make_readonly(ptel);
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is_io = hpte_cache_bits(pte_val(pte));
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pa = pte_pfn(pte) << PAGE_SHIFT;
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}
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}
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if (pte_size < psize)
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return H_PARAMETER;
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if (pa && pte_size > psize)
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pa |= gpa & (pte_size - 1);
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ptel &= ~(HPTE_R_PP0 - psize);
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ptel |= pa;
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if (pa)
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pteh |= HPTE_V_VALID;
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else
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pteh |= HPTE_V_ABSENT;
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/* Check WIMG */
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if (is_io != ~0ul && !hpte_cache_flags_ok(ptel, is_io)) {
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if (is_io)
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return H_PARAMETER;
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/*
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* Allow guest to map emulated device memory as
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* uncacheable, but actually make it cacheable.
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*/
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ptel &= ~(HPTE_R_W|HPTE_R_I|HPTE_R_G);
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ptel |= HPTE_R_M;
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}
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/* Find and lock the HPTEG slot to use */
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do_insert:
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if (pte_index >= HPT_NPTE)
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return H_PARAMETER;
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if (likely((flags & H_EXACT) == 0)) {
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pte_index &= ~7UL;
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hpte = (unsigned long *)(kvm->arch.hpt_virt + (pte_index << 4));
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for (i = 0; i < 8; ++i) {
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if ((*hpte & HPTE_V_VALID) == 0 &&
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try_lock_hpte(hpte, HPTE_V_HVLOCK | HPTE_V_VALID |
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HPTE_V_ABSENT))
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break;
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hpte += 2;
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}
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if (i == 8) {
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/*
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* Since try_lock_hpte doesn't retry (not even stdcx.
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* failures), it could be that there is a free slot
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* but we transiently failed to lock it. Try again,
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* actually locking each slot and checking it.
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*/
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hpte -= 16;
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for (i = 0; i < 8; ++i) {
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while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
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cpu_relax();
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if (!(*hpte & (HPTE_V_VALID | HPTE_V_ABSENT)))
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break;
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*hpte &= ~HPTE_V_HVLOCK;
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hpte += 2;
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}
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if (i == 8)
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return H_PTEG_FULL;
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}
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pte_index += i;
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} else {
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hpte = (unsigned long *)(kvm->arch.hpt_virt + (pte_index << 4));
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if (!try_lock_hpte(hpte, HPTE_V_HVLOCK | HPTE_V_VALID |
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HPTE_V_ABSENT)) {
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/* Lock the slot and check again */
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while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
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cpu_relax();
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if (*hpte & (HPTE_V_VALID | HPTE_V_ABSENT)) {
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*hpte &= ~HPTE_V_HVLOCK;
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return H_PTEG_FULL;
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}
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}
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}
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/* Save away the guest's idea of the second HPTE dword */
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rev = &kvm->arch.revmap[pte_index];
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if (realmode)
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rev = real_vmalloc_addr(rev);
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if (rev)
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rev->guest_rpte = g_ptel;
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/* Link HPTE into reverse-map chain */
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if (pteh & HPTE_V_VALID) {
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if (realmode)
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rmap = real_vmalloc_addr(rmap);
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lock_rmap(rmap);
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/* Check for pending invalidations under the rmap chain lock */
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if (kvm->arch.using_mmu_notifiers &&
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mmu_notifier_retry(vcpu, mmu_seq)) {
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/* inval in progress, write a non-present HPTE */
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pteh |= HPTE_V_ABSENT;
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pteh &= ~HPTE_V_VALID;
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unlock_rmap(rmap);
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} else {
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kvmppc_add_revmap_chain(kvm, rev, rmap, pte_index,
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realmode);
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}
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}
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hpte[1] = ptel;
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/* Write the first HPTE dword, unlocking the HPTE and making it valid */
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eieio();
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hpte[0] = pteh;
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asm volatile("ptesync" : : : "memory");
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vcpu->arch.gpr[4] = pte_index;
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return H_SUCCESS;
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}
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EXPORT_SYMBOL_GPL(kvmppc_h_enter);
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#define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token))
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static inline int try_lock_tlbie(unsigned int *lock)
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{
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unsigned int tmp, old;
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unsigned int token = LOCK_TOKEN;
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asm volatile("1:lwarx %1,0,%2\n"
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" cmpwi cr0,%1,0\n"
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" bne 2f\n"
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" stwcx. %3,0,%2\n"
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" bne- 1b\n"
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" isync\n"
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"2:"
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: "=&r" (tmp), "=&r" (old)
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: "r" (lock), "r" (token)
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: "cc", "memory");
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return old == 0;
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}
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long kvmppc_h_remove(struct kvm_vcpu *vcpu, unsigned long flags,
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unsigned long pte_index, unsigned long avpn,
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unsigned long va)
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{
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struct kvm *kvm = vcpu->kvm;
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unsigned long *hpte;
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unsigned long v, r, rb;
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struct revmap_entry *rev;
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if (pte_index >= HPT_NPTE)
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return H_PARAMETER;
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hpte = (unsigned long *)(kvm->arch.hpt_virt + (pte_index << 4));
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while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
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cpu_relax();
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if ((hpte[0] & (HPTE_V_ABSENT | HPTE_V_VALID)) == 0 ||
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((flags & H_AVPN) && (hpte[0] & ~0x7fUL) != avpn) ||
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((flags & H_ANDCOND) && (hpte[0] & avpn) != 0)) {
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hpte[0] &= ~HPTE_V_HVLOCK;
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return H_NOT_FOUND;
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}
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rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
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v = hpte[0] & ~HPTE_V_HVLOCK;
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if (v & HPTE_V_VALID) {
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hpte[0] &= ~HPTE_V_VALID;
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rb = compute_tlbie_rb(v, hpte[1], pte_index);
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if (!(flags & H_LOCAL) && atomic_read(&kvm->online_vcpus) > 1) {
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while (!try_lock_tlbie(&kvm->arch.tlbie_lock))
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cpu_relax();
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asm volatile("ptesync" : : : "memory");
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asm volatile(PPC_TLBIE(%1,%0)"; eieio; tlbsync"
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: : "r" (rb), "r" (kvm->arch.lpid));
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asm volatile("ptesync" : : : "memory");
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kvm->arch.tlbie_lock = 0;
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} else {
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asm volatile("ptesync" : : : "memory");
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asm volatile("tlbiel %0" : : "r" (rb));
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asm volatile("ptesync" : : : "memory");
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}
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remove_revmap_chain(kvm, pte_index, v);
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}
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r = rev->guest_rpte;
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unlock_hpte(hpte, 0);
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vcpu->arch.gpr[4] = v;
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vcpu->arch.gpr[5] = r;
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return H_SUCCESS;
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}
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long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu)
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{
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struct kvm *kvm = vcpu->kvm;
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unsigned long *args = &vcpu->arch.gpr[4];
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unsigned long *hp, *hptes[4], tlbrb[4];
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long int i, j, k, n, found, indexes[4];
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unsigned long flags, req, pte_index, rcbits;
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long int local = 0;
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long int ret = H_SUCCESS;
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struct revmap_entry *rev, *revs[4];
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if (atomic_read(&kvm->online_vcpus) == 1)
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local = 1;
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for (i = 0; i < 4 && ret == H_SUCCESS; ) {
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n = 0;
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for (; i < 4; ++i) {
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j = i * 2;
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pte_index = args[j];
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flags = pte_index >> 56;
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pte_index &= ((1ul << 56) - 1);
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req = flags >> 6;
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flags &= 3;
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if (req == 3) { /* no more requests */
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i = 4;
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break;
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}
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if (req != 1 || flags == 3 || pte_index >= HPT_NPTE) {
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/* parameter error */
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args[j] = ((0xa0 | flags) << 56) + pte_index;
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ret = H_PARAMETER;
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break;
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}
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hp = (unsigned long *)
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(kvm->arch.hpt_virt + (pte_index << 4));
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/* to avoid deadlock, don't spin except for first */
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if (!try_lock_hpte(hp, HPTE_V_HVLOCK)) {
|
|
if (n)
|
|
break;
|
|
while (!try_lock_hpte(hp, HPTE_V_HVLOCK))
|
|
cpu_relax();
|
|
}
|
|
found = 0;
|
|
if (hp[0] & (HPTE_V_ABSENT | HPTE_V_VALID)) {
|
|
switch (flags & 3) {
|
|
case 0: /* absolute */
|
|
found = 1;
|
|
break;
|
|
case 1: /* andcond */
|
|
if (!(hp[0] & args[j + 1]))
|
|
found = 1;
|
|
break;
|
|
case 2: /* AVPN */
|
|
if ((hp[0] & ~0x7fUL) == args[j + 1])
|
|
found = 1;
|
|
break;
|
|
}
|
|
}
|
|
if (!found) {
|
|
hp[0] &= ~HPTE_V_HVLOCK;
|
|
args[j] = ((0x90 | flags) << 56) + pte_index;
|
|
continue;
|
|
}
|
|
|
|
args[j] = ((0x80 | flags) << 56) + pte_index;
|
|
rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
|
|
/* insert R and C bits from guest PTE */
|
|
rcbits = rev->guest_rpte & (HPTE_R_R|HPTE_R_C);
|
|
args[j] |= rcbits << (56 - 5);
|
|
|
|
if (!(hp[0] & HPTE_V_VALID))
|
|
continue;
|
|
|
|
hp[0] &= ~HPTE_V_VALID; /* leave it locked */
|
|
tlbrb[n] = compute_tlbie_rb(hp[0], hp[1], pte_index);
|
|
indexes[n] = j;
|
|
hptes[n] = hp;
|
|
revs[n] = rev;
|
|
++n;
|
|
}
|
|
|
|
if (!n)
|
|
break;
|
|
|
|
/* Now that we've collected a batch, do the tlbies */
|
|
if (!local) {
|
|
while(!try_lock_tlbie(&kvm->arch.tlbie_lock))
|
|
cpu_relax();
|
|
asm volatile("ptesync" : : : "memory");
|
|
for (k = 0; k < n; ++k)
|
|
asm volatile(PPC_TLBIE(%1,%0) : :
|
|
"r" (tlbrb[k]),
|
|
"r" (kvm->arch.lpid));
|
|
asm volatile("eieio; tlbsync; ptesync" : : : "memory");
|
|
kvm->arch.tlbie_lock = 0;
|
|
} else {
|
|
asm volatile("ptesync" : : : "memory");
|
|
for (k = 0; k < n; ++k)
|
|
asm volatile("tlbiel %0" : : "r" (tlbrb[k]));
|
|
asm volatile("ptesync" : : : "memory");
|
|
}
|
|
|
|
for (k = 0; k < n; ++k) {
|
|
j = indexes[k];
|
|
pte_index = args[j] & ((1ul << 56) - 1);
|
|
hp = hptes[k];
|
|
rev = revs[k];
|
|
remove_revmap_chain(kvm, pte_index, hp[0]);
|
|
unlock_hpte(hp, 0);
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags,
|
|
unsigned long pte_index, unsigned long avpn,
|
|
unsigned long va)
|
|
{
|
|
struct kvm *kvm = vcpu->kvm;
|
|
unsigned long *hpte;
|
|
struct revmap_entry *rev;
|
|
unsigned long v, r, rb, mask, bits;
|
|
|
|
if (pte_index >= HPT_NPTE)
|
|
return H_PARAMETER;
|
|
|
|
hpte = (unsigned long *)(kvm->arch.hpt_virt + (pte_index << 4));
|
|
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
|
|
cpu_relax();
|
|
if ((hpte[0] & (HPTE_V_ABSENT | HPTE_V_VALID)) == 0 ||
|
|
((flags & H_AVPN) && (hpte[0] & ~0x7fUL) != avpn)) {
|
|
hpte[0] &= ~HPTE_V_HVLOCK;
|
|
return H_NOT_FOUND;
|
|
}
|
|
|
|
if (atomic_read(&kvm->online_vcpus) == 1)
|
|
flags |= H_LOCAL;
|
|
v = hpte[0];
|
|
bits = (flags << 55) & HPTE_R_PP0;
|
|
bits |= (flags << 48) & HPTE_R_KEY_HI;
|
|
bits |= flags & (HPTE_R_PP | HPTE_R_N | HPTE_R_KEY_LO);
|
|
|
|
/* Update guest view of 2nd HPTE dword */
|
|
mask = HPTE_R_PP0 | HPTE_R_PP | HPTE_R_N |
|
|
HPTE_R_KEY_HI | HPTE_R_KEY_LO;
|
|
rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
|
|
if (rev) {
|
|
r = (rev->guest_rpte & ~mask) | bits;
|
|
rev->guest_rpte = r;
|
|
}
|
|
r = (hpte[1] & ~mask) | bits;
|
|
|
|
/* Update HPTE */
|
|
if (v & HPTE_V_VALID) {
|
|
rb = compute_tlbie_rb(v, r, pte_index);
|
|
hpte[0] = v & ~HPTE_V_VALID;
|
|
if (!(flags & H_LOCAL)) {
|
|
while(!try_lock_tlbie(&kvm->arch.tlbie_lock))
|
|
cpu_relax();
|
|
asm volatile("ptesync" : : : "memory");
|
|
asm volatile(PPC_TLBIE(%1,%0)"; eieio; tlbsync"
|
|
: : "r" (rb), "r" (kvm->arch.lpid));
|
|
asm volatile("ptesync" : : : "memory");
|
|
kvm->arch.tlbie_lock = 0;
|
|
} else {
|
|
asm volatile("ptesync" : : : "memory");
|
|
asm volatile("tlbiel %0" : : "r" (rb));
|
|
asm volatile("ptesync" : : : "memory");
|
|
}
|
|
}
|
|
hpte[1] = r;
|
|
eieio();
|
|
hpte[0] = v & ~HPTE_V_HVLOCK;
|
|
asm volatile("ptesync" : : : "memory");
|
|
return H_SUCCESS;
|
|
}
|
|
|
|
long kvmppc_h_read(struct kvm_vcpu *vcpu, unsigned long flags,
|
|
unsigned long pte_index)
|
|
{
|
|
struct kvm *kvm = vcpu->kvm;
|
|
unsigned long *hpte, v, r;
|
|
int i, n = 1;
|
|
struct revmap_entry *rev = NULL;
|
|
|
|
if (pte_index >= HPT_NPTE)
|
|
return H_PARAMETER;
|
|
if (flags & H_READ_4) {
|
|
pte_index &= ~3;
|
|
n = 4;
|
|
}
|
|
if (flags & H_R_XLATE)
|
|
rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
|
|
for (i = 0; i < n; ++i, ++pte_index) {
|
|
hpte = (unsigned long *)(kvm->arch.hpt_virt + (pte_index << 4));
|
|
v = hpte[0] & ~HPTE_V_HVLOCK;
|
|
r = hpte[1];
|
|
if (v & HPTE_V_ABSENT) {
|
|
v &= ~HPTE_V_ABSENT;
|
|
v |= HPTE_V_VALID;
|
|
}
|
|
if (v & HPTE_V_VALID) {
|
|
if (rev)
|
|
r = rev[i].guest_rpte;
|
|
else
|
|
r = hpte[1] | HPTE_R_RPN;
|
|
}
|
|
vcpu->arch.gpr[4 + i * 2] = v;
|
|
vcpu->arch.gpr[5 + i * 2] = r;
|
|
}
|
|
return H_SUCCESS;
|
|
}
|
|
|
|
void kvmppc_invalidate_hpte(struct kvm *kvm, unsigned long *hptep,
|
|
unsigned long pte_index)
|
|
{
|
|
unsigned long rb;
|
|
|
|
hptep[0] &= ~HPTE_V_VALID;
|
|
rb = compute_tlbie_rb(hptep[0], hptep[1], pte_index);
|
|
while (!try_lock_tlbie(&kvm->arch.tlbie_lock))
|
|
cpu_relax();
|
|
asm volatile("ptesync" : : : "memory");
|
|
asm volatile(PPC_TLBIE(%1,%0)"; eieio; tlbsync"
|
|
: : "r" (rb), "r" (kvm->arch.lpid));
|
|
asm volatile("ptesync" : : : "memory");
|
|
kvm->arch.tlbie_lock = 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvmppc_invalidate_hpte);
|
|
|
|
static int slb_base_page_shift[4] = {
|
|
24, /* 16M */
|
|
16, /* 64k */
|
|
34, /* 16G */
|
|
20, /* 1M, unsupported */
|
|
};
|
|
|
|
long kvmppc_hv_find_lock_hpte(struct kvm *kvm, gva_t eaddr, unsigned long slb_v,
|
|
unsigned long valid)
|
|
{
|
|
unsigned int i;
|
|
unsigned int pshift;
|
|
unsigned long somask;
|
|
unsigned long vsid, hash;
|
|
unsigned long avpn;
|
|
unsigned long *hpte;
|
|
unsigned long mask, val;
|
|
unsigned long v, r;
|
|
|
|
/* Get page shift, work out hash and AVPN etc. */
|
|
mask = SLB_VSID_B | HPTE_V_AVPN | HPTE_V_SECONDARY;
|
|
val = 0;
|
|
pshift = 12;
|
|
if (slb_v & SLB_VSID_L) {
|
|
mask |= HPTE_V_LARGE;
|
|
val |= HPTE_V_LARGE;
|
|
pshift = slb_base_page_shift[(slb_v & SLB_VSID_LP) >> 4];
|
|
}
|
|
if (slb_v & SLB_VSID_B_1T) {
|
|
somask = (1UL << 40) - 1;
|
|
vsid = (slb_v & ~SLB_VSID_B) >> SLB_VSID_SHIFT_1T;
|
|
vsid ^= vsid << 25;
|
|
} else {
|
|
somask = (1UL << 28) - 1;
|
|
vsid = (slb_v & ~SLB_VSID_B) >> SLB_VSID_SHIFT;
|
|
}
|
|
hash = (vsid ^ ((eaddr & somask) >> pshift)) & HPT_HASH_MASK;
|
|
avpn = slb_v & ~(somask >> 16); /* also includes B */
|
|
avpn |= (eaddr & somask) >> 16;
|
|
|
|
if (pshift >= 24)
|
|
avpn &= ~((1UL << (pshift - 16)) - 1);
|
|
else
|
|
avpn &= ~0x7fUL;
|
|
val |= avpn;
|
|
|
|
for (;;) {
|
|
hpte = (unsigned long *)(kvm->arch.hpt_virt + (hash << 7));
|
|
|
|
for (i = 0; i < 16; i += 2) {
|
|
/* Read the PTE racily */
|
|
v = hpte[i] & ~HPTE_V_HVLOCK;
|
|
|
|
/* Check valid/absent, hash, segment size and AVPN */
|
|
if (!(v & valid) || (v & mask) != val)
|
|
continue;
|
|
|
|
/* Lock the PTE and read it under the lock */
|
|
while (!try_lock_hpte(&hpte[i], HPTE_V_HVLOCK))
|
|
cpu_relax();
|
|
v = hpte[i] & ~HPTE_V_HVLOCK;
|
|
r = hpte[i+1];
|
|
|
|
/*
|
|
* Check the HPTE again, including large page size
|
|
* Since we don't currently allow any MPSS (mixed
|
|
* page-size segment) page sizes, it is sufficient
|
|
* to check against the actual page size.
|
|
*/
|
|
if ((v & valid) && (v & mask) == val &&
|
|
hpte_page_size(v, r) == (1ul << pshift))
|
|
/* Return with the HPTE still locked */
|
|
return (hash << 3) + (i >> 1);
|
|
|
|
/* Unlock and move on */
|
|
hpte[i] = v;
|
|
}
|
|
|
|
if (val & HPTE_V_SECONDARY)
|
|
break;
|
|
val |= HPTE_V_SECONDARY;
|
|
hash = hash ^ HPT_HASH_MASK;
|
|
}
|
|
return -1;
|
|
}
|
|
EXPORT_SYMBOL(kvmppc_hv_find_lock_hpte);
|
|
|
|
/*
|
|
* Called in real mode to check whether an HPTE not found fault
|
|
* is due to accessing a paged-out page or an emulated MMIO page,
|
|
* or if a protection fault is due to accessing a page that the
|
|
* guest wanted read/write access to but which we made read-only.
|
|
* Returns a possibly modified status (DSISR) value if not
|
|
* (i.e. pass the interrupt to the guest),
|
|
* -1 to pass the fault up to host kernel mode code, -2 to do that
|
|
* and also load the instruction word (for MMIO emulation),
|
|
* or 0 if we should make the guest retry the access.
|
|
*/
|
|
long kvmppc_hpte_hv_fault(struct kvm_vcpu *vcpu, unsigned long addr,
|
|
unsigned long slb_v, unsigned int status, bool data)
|
|
{
|
|
struct kvm *kvm = vcpu->kvm;
|
|
long int index;
|
|
unsigned long v, r, gr;
|
|
unsigned long *hpte;
|
|
unsigned long valid;
|
|
struct revmap_entry *rev;
|
|
unsigned long pp, key;
|
|
|
|
/* For protection fault, expect to find a valid HPTE */
|
|
valid = HPTE_V_VALID;
|
|
if (status & DSISR_NOHPTE)
|
|
valid |= HPTE_V_ABSENT;
|
|
|
|
index = kvmppc_hv_find_lock_hpte(kvm, addr, slb_v, valid);
|
|
if (index < 0) {
|
|
if (status & DSISR_NOHPTE)
|
|
return status; /* there really was no HPTE */
|
|
return 0; /* for prot fault, HPTE disappeared */
|
|
}
|
|
hpte = (unsigned long *)(kvm->arch.hpt_virt + (index << 4));
|
|
v = hpte[0] & ~HPTE_V_HVLOCK;
|
|
r = hpte[1];
|
|
rev = real_vmalloc_addr(&kvm->arch.revmap[index]);
|
|
gr = rev->guest_rpte;
|
|
|
|
unlock_hpte(hpte, v);
|
|
|
|
/* For not found, if the HPTE is valid by now, retry the instruction */
|
|
if ((status & DSISR_NOHPTE) && (v & HPTE_V_VALID))
|
|
return 0;
|
|
|
|
/* Check access permissions to the page */
|
|
pp = gr & (HPTE_R_PP0 | HPTE_R_PP);
|
|
key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;
|
|
status &= ~DSISR_NOHPTE; /* DSISR_NOHPTE == SRR1_ISI_NOPT */
|
|
if (!data) {
|
|
if (gr & (HPTE_R_N | HPTE_R_G))
|
|
return status | SRR1_ISI_N_OR_G;
|
|
if (!hpte_read_permission(pp, slb_v & key))
|
|
return status | SRR1_ISI_PROT;
|
|
} else if (status & DSISR_ISSTORE) {
|
|
/* check write permission */
|
|
if (!hpte_write_permission(pp, slb_v & key))
|
|
return status | DSISR_PROTFAULT;
|
|
} else {
|
|
if (!hpte_read_permission(pp, slb_v & key))
|
|
return status | DSISR_PROTFAULT;
|
|
}
|
|
|
|
/* Check storage key, if applicable */
|
|
if (data && (vcpu->arch.shregs.msr & MSR_DR)) {
|
|
unsigned int perm = hpte_get_skey_perm(gr, vcpu->arch.amr);
|
|
if (status & DSISR_ISSTORE)
|
|
perm >>= 1;
|
|
if (perm & 1)
|
|
return status | DSISR_KEYFAULT;
|
|
}
|
|
|
|
/* Save HPTE info for virtual-mode handler */
|
|
vcpu->arch.pgfault_addr = addr;
|
|
vcpu->arch.pgfault_index = index;
|
|
vcpu->arch.pgfault_hpte[0] = v;
|
|
vcpu->arch.pgfault_hpte[1] = r;
|
|
|
|
/* Check the storage key to see if it is possibly emulated MMIO */
|
|
if (data && (vcpu->arch.shregs.msr & MSR_IR) &&
|
|
(r & (HPTE_R_KEY_HI | HPTE_R_KEY_LO)) ==
|
|
(HPTE_R_KEY_HI | HPTE_R_KEY_LO))
|
|
return -2; /* MMIO emulation - load instr word */
|
|
|
|
return -1; /* send fault up to host kernel mode */
|
|
}
|