diff options
| -rw-r--r-- | arch/powerpc/include/asm/kvm_book3s_64.h | 18 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/kvm_host.h | 17 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rm_mmu.c | 84 |
3 files changed, 117 insertions, 2 deletions
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h index 18b590d261ff..9508c03e6671 100644 --- a/arch/powerpc/include/asm/kvm_book3s_64.h +++ b/arch/powerpc/include/asm/kvm_book3s_64.h @@ -113,6 +113,11 @@ static inline unsigned long hpte_page_size(unsigned long h, unsigned long l) return 0; /* error */ } +static inline unsigned long hpte_rpn(unsigned long ptel, unsigned long psize) +{ + return ((ptel & HPTE_R_RPN) & ~(psize - 1)) >> PAGE_SHIFT; +} + static inline int hpte_cache_flags_ok(unsigned long ptel, unsigned long io_type) { unsigned int wimg = ptel & HPTE_R_WIMG; @@ -139,6 +144,19 @@ static inline unsigned long hpte_cache_bits(unsigned long pte_val) #endif } +static inline void lock_rmap(unsigned long *rmap) +{ + do { + while (test_bit(KVMPPC_RMAP_LOCK_BIT, rmap)) + cpu_relax(); + } while (test_and_set_bit_lock(KVMPPC_RMAP_LOCK_BIT, rmap)); +} + +static inline void unlock_rmap(unsigned long *rmap) +{ + __clear_bit_unlock(KVMPPC_RMAP_LOCK_BIT, rmap); +} + static inline bool slot_is_aligned(struct kvm_memory_slot *memslot, unsigned long pagesize) { diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 243bc8038572..97cb2d7865f3 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -170,12 +170,27 @@ struct kvmppc_rma_info { /* * The reverse mapping array has one entry for each HPTE, * which stores the guest's view of the second word of the HPTE - * (including the guest physical address of the mapping). + * (including the guest physical address of the mapping), + * plus forward and backward pointers in a doubly-linked ring + * of HPTEs that map the same host page. The pointers in this + * ring are 32-bit HPTE indexes, to save space. */ struct revmap_entry { unsigned long guest_rpte; + unsigned int forw, back; }; +/* + * We use the top bit of each memslot->rmap entry as a lock bit, + * and bit 32 as a present flag. The bottom 32 bits are the + * index in the guest HPT of a HPTE that points to the page. + */ +#define KVMPPC_RMAP_LOCK_BIT 63 +#define KVMPPC_RMAP_REF_BIT 33 +#define KVMPPC_RMAP_REFERENCED (1ul << KVMPPC_RMAP_REF_BIT) +#define KVMPPC_RMAP_PRESENT 0x100000000ul +#define KVMPPC_RMAP_INDEX 0xfffffffful + /* Low-order bits in kvm->arch.slot_phys[][] */ #define KVMPPC_PAGE_ORDER_MASK 0x1f #define KVMPPC_PAGE_NO_CACHE HPTE_R_I /* 0x20 */ diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index 3f5b016490d0..5b31caa4b314 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -54,6 +54,70 @@ static void *real_vmalloc_addr(void *x) return __va(addr); } +/* + * Add this HPTE into the chain for the real page. + * Must be called with the chain locked; it unlocks the chain. + */ +static void kvmppc_add_revmap_chain(struct kvm *kvm, struct revmap_entry *rev, + unsigned long *rmap, long pte_index, int realmode) +{ + struct revmap_entry *head, *tail; + unsigned long i; + + if (*rmap & KVMPPC_RMAP_PRESENT) { + i = *rmap & KVMPPC_RMAP_INDEX; + head = &kvm->arch.revmap[i]; + if (realmode) + head = real_vmalloc_addr(head); + tail = &kvm->arch.revmap[head->back]; + if (realmode) + tail = real_vmalloc_addr(tail); + rev->forw = i; + rev->back = head->back; + tail->forw = pte_index; + head->back = pte_index; + } else { + rev->forw = rev->back = pte_index; + i = pte_index; + } + smp_wmb(); + *rmap = i | KVMPPC_RMAP_REFERENCED | KVMPPC_RMAP_PRESENT; /* unlock */ +} + +/* Remove this HPTE from the chain for a real page */ +static void remove_revmap_chain(struct kvm *kvm, long pte_index, + unsigned long hpte_v) +{ + struct revmap_entry *rev, *next, *prev; + unsigned long gfn, ptel, head; + struct kvm_memory_slot *memslot; + unsigned long *rmap; + + rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]); + ptel = rev->guest_rpte; + gfn = hpte_rpn(ptel, hpte_page_size(hpte_v, ptel)); + memslot = builtin_gfn_to_memslot(kvm, gfn); + if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) + return; + + rmap = real_vmalloc_addr(&memslot->rmap[gfn - memslot->base_gfn]); + lock_rmap(rmap); + + head = *rmap & KVMPPC_RMAP_INDEX; + next = real_vmalloc_addr(&kvm->arch.revmap[rev->forw]); + prev = real_vmalloc_addr(&kvm->arch.revmap[rev->back]); + next->back = rev->back; + prev->forw = rev->forw; + if (head == pte_index) { + head = rev->forw; + if (head == pte_index) + *rmap &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX); + else + *rmap = (*rmap & ~KVMPPC_RMAP_INDEX) | head; + } + unlock_rmap(rmap); +} + long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, long pte_index, unsigned long pteh, unsigned long ptel) { @@ -66,6 +130,7 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, struct kvm_memory_slot *memslot; unsigned long *physp, pte_size; unsigned long is_io; + unsigned long *rmap; bool realmode = vcpu->arch.vcore->vcore_state == VCORE_RUNNING; psize = hpte_page_size(pteh, ptel); @@ -83,6 +148,7 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, if (!slot_is_aligned(memslot, psize)) return H_PARAMETER; slot_fn = gfn - memslot->base_gfn; + rmap = &memslot->rmap[slot_fn]; physp = kvm->arch.slot_phys[memslot->id]; if (!physp) @@ -164,13 +230,25 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, } /* Save away the guest's idea of the second HPTE dword */ - rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]); + rev = &kvm->arch.revmap[pte_index]; + if (realmode) + rev = real_vmalloc_addr(rev); if (rev) rev->guest_rpte = g_ptel; + + /* Link HPTE into reverse-map chain */ + if (realmode) + rmap = real_vmalloc_addr(rmap); + lock_rmap(rmap); + kvmppc_add_revmap_chain(kvm, rev, rmap, pte_index, realmode); + hpte[1] = ptel; + + /* Write the first HPTE dword, unlocking the HPTE and making it valid */ eieio(); hpte[0] = pteh; asm volatile("ptesync" : : : "memory"); + vcpu->arch.gpr[4] = pte_index; return H_SUCCESS; } @@ -220,6 +298,8 @@ long kvmppc_h_remove(struct kvm_vcpu *vcpu, unsigned long flags, vcpu->arch.gpr[4] = v = hpte[0] & ~HPTE_V_HVLOCK; vcpu->arch.gpr[5] = r = hpte[1]; rb = compute_tlbie_rb(v, r, pte_index); + remove_revmap_chain(kvm, pte_index, v); + smp_wmb(); hpte[0] = 0; if (!(flags & H_LOCAL)) { while(!try_lock_tlbie(&kvm->arch.tlbie_lock)) @@ -293,6 +373,8 @@ long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu) flags |= (hp[1] >> 5) & 0x0c; args[i * 2] = ((0x80 | flags) << 56) + pte_index; tlbrb[n_inval++] = compute_tlbie_rb(hp[0], hp[1], pte_index); + remove_revmap_chain(kvm, pte_index, hp[0]); + smp_wmb(); hp[0] = 0; } if (n_inval == 0) |