/* * Copyright 2011 Paul Mackerras, IBM Corp. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License, version 2, as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define KVM_CMA_CHUNK_ORDER 18 #include "book3s_xics.h" #include "book3s_xive.h" /* * The XIVE module will populate these when it loads */ unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu); unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server); int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server, unsigned long mfrr); int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr); int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr); EXPORT_SYMBOL_GPL(__xive_vm_h_xirr); EXPORT_SYMBOL_GPL(__xive_vm_h_ipoll); EXPORT_SYMBOL_GPL(__xive_vm_h_ipi); EXPORT_SYMBOL_GPL(__xive_vm_h_cppr); EXPORT_SYMBOL_GPL(__xive_vm_h_eoi); /* * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206) * should be power of 2. */ #define HPT_ALIGN_PAGES ((1 << 18) >> PAGE_SHIFT) /* 256k */ /* * By default we reserve 5% of memory for hash pagetable allocation. */ static unsigned long kvm_cma_resv_ratio = 5; static struct cma *kvm_cma; static int __init early_parse_kvm_cma_resv(char *p) { pr_debug("%s(%s)\n", __func__, p); if (!p) return -EINVAL; return kstrtoul(p, 0, &kvm_cma_resv_ratio); } early_param("kvm_cma_resv_ratio", early_parse_kvm_cma_resv); struct page *kvm_alloc_hpt_cma(unsigned long nr_pages) { VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES), GFP_KERNEL); } EXPORT_SYMBOL_GPL(kvm_alloc_hpt_cma); void kvm_free_hpt_cma(struct page *page, unsigned long nr_pages) { cma_release(kvm_cma, page, nr_pages); } EXPORT_SYMBOL_GPL(kvm_free_hpt_cma); /** * kvm_cma_reserve() - reserve area for kvm hash pagetable * * This function reserves memory from early allocator. It should be * called by arch specific code once the memblock allocator * has been activated and all other subsystems have already allocated/reserved * memory. */ void __init kvm_cma_reserve(void) { unsigned long align_size; struct memblock_region *reg; phys_addr_t selected_size = 0; /* * We need CMA reservation only when we are in HV mode */ if (!cpu_has_feature(CPU_FTR_HVMODE)) return; /* * We cannot use memblock_phys_mem_size() here, because * memblock_analyze() has not been called yet. */ for_each_memblock(memory, reg) selected_size += memblock_region_memory_end_pfn(reg) - memblock_region_memory_base_pfn(reg); selected_size = (selected_size * kvm_cma_resv_ratio / 100) << PAGE_SHIFT; if (selected_size) { pr_debug("%s: reserving %ld MiB for global area\n", __func__, (unsigned long)selected_size / SZ_1M); align_size = HPT_ALIGN_PAGES << PAGE_SHIFT; cma_declare_contiguous(0, selected_size, 0, align_size, KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, false, "kvm_cma", &kvm_cma); } } /* * Real-mode H_CONFER implementation. * We check if we are the only vcpu out of this virtual core * still running in the guest and not ceded. If so, we pop up * to the virtual-mode implementation; if not, just return to * the guest. */ long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target, unsigned int yield_count) { struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore; int ptid = local_paca->kvm_hstate.ptid; int threads_running; int threads_ceded; int threads_conferring; u64 stop = get_tb() + 10 * tb_ticks_per_usec; int rv = H_SUCCESS; /* => don't yield */ set_bit(ptid, &vc->conferring_threads); while ((get_tb() < stop) && !VCORE_IS_EXITING(vc)) { threads_running = VCORE_ENTRY_MAP(vc); threads_ceded = vc->napping_threads; threads_conferring = vc->conferring_threads; if ((threads_ceded | threads_conferring) == threads_running) { rv = H_TOO_HARD; /* => do yield */ break; } } clear_bit(ptid, &vc->conferring_threads); return rv; } /* * When running HV mode KVM we need to block certain operations while KVM VMs * exist in the system. We use a counter of VMs to track this. * * One of the operations we need to block is onlining of secondaries, so we * protect hv_vm_count with get/put_online_cpus(). */ static atomic_t hv_vm_count; void kvm_hv_vm_activated(void) { get_online_cpus(); atomic_inc(&hv_vm_count); put_online_cpus(); } EXPORT_SYMBOL_GPL(kvm_hv_vm_activated); void kvm_hv_vm_deactivated(void) { get_online_cpus(); atomic_dec(&hv_vm_count); put_online_cpus(); } EXPORT_SYMBOL_GPL(kvm_hv_vm_deactivated); bool kvm_hv_mode_active(void) { return atomic_read(&hv_vm_count) != 0; } extern int hcall_real_table[], hcall_real_table_end[]; int kvmppc_hcall_impl_hv_realmode(unsigned long cmd) { cmd /= 4; if (cmd < hcall_real_table_end - hcall_real_table && hcall_real_table[cmd]) return 1; return 0; } EXPORT_SYMBOL_GPL(kvmppc_hcall_impl_hv_realmode); int kvmppc_hwrng_present(void) { return powernv_hwrng_present(); } EXPORT_SYMBOL_GPL(kvmppc_hwrng_present); long kvmppc_h_random(struct kvm_vcpu *vcpu) { int r; /* Only need to do the expensive mfmsr() on radix */ if (kvm_is_radix(vcpu->kvm) && (mfmsr() & MSR_IR)) r = powernv_get_random_long(&vcpu->arch.gpr[4]); else r = powernv_get_random_real_mode(&vcpu->arch.gpr[4]); if (r) return H_SUCCESS; return H_HARDWARE; } /* * Send an interrupt or message to another CPU. * The caller needs to include any barrier needed to order writes * to memory vs. the IPI/message. */ void kvmhv_rm_send_ipi(int cpu) { void __iomem *xics_phys; unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER); /* On POWER9 we can use msgsnd for any destination cpu. */ if (cpu_has_feature(CPU_FTR_ARCH_300)) { msg |= get_hard_smp_processor_id(cpu); __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg)); return; } /* On POWER8 for IPIs to threads in the same core, use msgsnd. */ if (cpu_has_feature(CPU_FTR_ARCH_207S) && cpu_first_thread_sibling(cpu) == cpu_first_thread_sibling(raw_smp_processor_id())) { msg |= cpu_thread_in_core(cpu); __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg)); return; } /* We should never reach this */ if (WARN_ON_ONCE(xive_enabled())) return; /* Else poke the target with an IPI */ xics_phys = paca[cpu].kvm_hstate.xics_phys; if (xics_phys) __raw_rm_writeb(IPI_PRIORITY, xics_phys + XICS_MFRR); else opal_int_set_mfrr(get_hard_smp_processor_id(cpu), IPI_PRIORITY); } /* * The following functions are called from the assembly code * in book3s_hv_rmhandlers.S. */ static void kvmhv_interrupt_vcore(struct kvmppc_vcore *vc, int active) { int cpu = vc->pcpu; /* Order setting of exit map vs. msgsnd/IPI */ smp_mb(); for (; active; active >>= 1, ++cpu) if (active & 1) kvmhv_rm_send_ipi(cpu); } void kvmhv_commence_exit(int trap) { struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore; int ptid = local_paca->kvm_hstate.ptid; struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode; int me, ee, i; /* Set our bit in the threads-exiting-guest map in the 0xff00 bits of vcore->entry_exit_map */ me = 0x100 << ptid; do { ee = vc->entry_exit_map; } while (cmpxchg(&vc->entry_exit_map, ee, ee | me) != ee); /* Are we the first here? */ if ((ee >> 8) != 0) return; /* * Trigger the other threads in this vcore to exit the guest. * If this is a hypervisor decrementer interrupt then they * will be already on their way out of the guest. */ if (trap != BOOK3S_INTERRUPT_HV_DECREMENTER) kvmhv_interrupt_vcore(vc, ee & ~(1 << ptid)); /* * If we are doing dynamic micro-threading, interrupt the other * subcores to pull them out of their guests too. */ if (!sip) return; for (i = 0; i < MAX_SUBCORES; ++i) { vc = sip->vc[i]; if (!vc) break; do { ee = vc->entry_exit_map; /* Already asked to exit? */ if ((ee >> 8) != 0) break; } while (cmpxchg(&vc->entry_exit_map, ee, ee | VCORE_EXIT_REQ) != ee); if ((ee >> 8) == 0) kvmhv_interrupt_vcore(vc, ee); } } struct kvmppc_host_rm_ops *kvmppc_host_rm_ops_hv; EXPORT_SYMBOL_GPL(kvmppc_host_rm_ops_hv); #ifdef CONFIG_KVM_XICS static struct kvmppc_irq_map *get_irqmap(struct kvmppc_passthru_irqmap *pimap, u32 xisr) { int i; /* * We access the mapped array here without a lock. That * is safe because we never reduce the number of entries * in the array and we never change the v_hwirq field of * an entry once it is set. * * We have also carefully ordered the stores in the writer * and the loads here in the reader, so that if we find a matching * hwirq here, the associated GSI and irq_desc fields are valid. */ for (i = 0; i < pimap->n_mapped; i++) { if (xisr == pimap->mapped[i].r_hwirq) { /* * Order subsequent reads in the caller to serialize * with the writer. */ smp_rmb(); return &pimap->mapped[i]; } } return NULL; } /* * If we have an interrupt that's not an IPI, check if we have a * passthrough adapter and if so, check if this external interrupt * is for the adapter. * We will attempt to deliver the IRQ directly to the target VCPU's * ICP, the virtual ICP (based on affinity - the xive value in ICS). * * If the delivery fails or if this is not for a passthrough adapter, * return to the host to handle this interrupt. We earlier * saved a copy of the XIRR in the PACA, it will be picked up by * the host ICP driver. */ static int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again) { struct kvmppc_passthru_irqmap *pimap; struct kvmppc_irq_map *irq_map; struct kvm_vcpu *vcpu; vcpu = local_paca->kvm_hstate.kvm_vcpu; if (!vcpu) return 1; pimap = kvmppc_get_passthru_irqmap(vcpu->kvm); if (!pimap) return 1; irq_map = get_irqmap(pimap, xisr); if (!irq_map) return 1; /* We're handling this interrupt, generic code doesn't need to */ local_paca->kvm_hstate.saved_xirr = 0; return kvmppc_deliver_irq_passthru(vcpu, xirr, irq_map, pimap, again); } #else static inline int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again) { return 1; } #endif /* * Determine what sort of external interrupt is pending (if any). * Returns: * 0 if no interrupt is pending * 1 if an interrupt is pending that needs to be handled by the host * 2 Passthrough that needs completion in the host * -1 if there was a guest wakeup IPI (which has now been cleared) * -2 if there is PCI passthrough external interrupt that was handled */ static long kvmppc_read_one_intr(bool *again); long kvmppc_read_intr(void) { long ret = 0; long rc; bool again; if (xive_enabled()) return 1; do { again = false; rc = kvmppc_read_one_intr(&again); if (rc && (ret == 0 || rc > ret)) ret = rc; } while (again); return ret; } static long kvmppc_read_one_intr(bool *again) { void __iomem *xics_phys; u32 h_xirr; __be32 xirr; u32 xisr; u8 host_ipi; int64_t rc; if (xive_enabled()) return 1; /* see if a host IPI is pending */ host_ipi = local_paca->kvm_hstate.host_ipi; if (host_ipi) return 1; /* Now read the interrupt from the ICP */ xics_phys = local_paca->kvm_hstate.xics_phys; rc = 0; if (!xics_phys) rc = opal_int_get_xirr(&xirr, false); else xirr = __raw_rm_readl(xics_phys + XICS_XIRR); if (rc < 0) return 1; /* * Save XIRR for later. Since we get control in reverse endian * on LE systems, save it byte reversed and fetch it back in * host endian. Note that xirr is the value read from the * XIRR register, while h_xirr is the host endian version. */ h_xirr = be32_to_cpu(xirr); local_paca->kvm_hstate.saved_xirr = h_xirr; xisr = h_xirr & 0xffffff; /* * Ensure that the store/load complete to guarantee all side * effects of loading from XIRR has completed */ smp_mb(); /* if nothing pending in the ICP */ if (!xisr) return 0; /* We found something in the ICP... * * If it is an IPI, clear the MFRR and EOI it. */ if (xisr == XICS_IPI) { rc = 0; if (xics_phys) { __raw_rm_writeb(0xff, xics_phys + XICS_MFRR); __raw_rm_writel(xirr, xics_phys + XICS_XIRR); } else { opal_int_set_mfrr(hard_smp_processor_id(), 0xff); rc = opal_int_eoi(h_xirr); } /* If rc > 0, there is another interrupt pending */ *again = rc > 0; /* * Need to ensure side effects of above stores * complete before proceeding. */ smp_mb(); /* * We need to re-check host IPI now in case it got set in the * meantime. If it's clear, we bounce the interrupt to the * guest */ host_ipi = local_paca->kvm_hstate.host_ipi; if (unlikely(host_ipi != 0)) { /* We raced with the host, * we need to resend that IPI, bummer */ if (xics_phys) __raw_rm_writeb(IPI_PRIORITY, xics_phys + XICS_MFRR); else opal_int_set_mfrr(hard_smp_processor_id(), IPI_PRIORITY); /* Let side effects complete */ smp_mb(); return 1; } /* OK, it's an IPI for us */ local_paca->kvm_hstate.saved_xirr = 0; return -1; } return kvmppc_check_passthru(xisr, xirr, again); } #ifdef CONFIG_KVM_XICS static inline bool is_rm(void) { return !(mfmsr() & MSR_DR); } unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu) { if (xive_enabled()) { if (is_rm()) return xive_rm_h_xirr(vcpu); if (unlikely(!__xive_vm_h_xirr)) return H_NOT_AVAILABLE; return __xive_vm_h_xirr(vcpu); } else return xics_rm_h_xirr(vcpu); } unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu) { vcpu->arch.gpr[5] = get_tb(); if (xive_enabled()) { if (is_rm()) return xive_rm_h_xirr(vcpu); if (unlikely(!__xive_vm_h_xirr)) return H_NOT_AVAILABLE; return __xive_vm_h_xirr(vcpu); } else return xics_rm_h_xirr(vcpu); } unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server) { if (xive_enabled()) { if (is_rm()) return xive_rm_h_ipoll(vcpu, server); if (unlikely(!__xive_vm_h_ipoll)) return H_NOT_AVAILABLE; return __xive_vm_h_ipoll(vcpu, server); } else return H_TOO_HARD; } int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server, unsigned long mfrr) { if (xive_enabled()) { if (is_rm()) return xive_rm_h_ipi(vcpu, server, mfrr); if (unlikely(!__xive_vm_h_ipi)) return H_NOT_AVAILABLE; return __xive_vm_h_ipi(vcpu, server, mfrr); } else return xics_rm_h_ipi(vcpu, server, mfrr); } int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) { if (xive_enabled()) { if (is_rm()) return xive_rm_h_cppr(vcpu, cppr); if (unlikely(!__xive_vm_h_cppr)) return H_NOT_AVAILABLE; return __xive_vm_h_cppr(vcpu, cppr); } else return xics_rm_h_cppr(vcpu, cppr); } int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) { if (xive_enabled()) { if (is_rm()) return xive_rm_h_eoi(vcpu, xirr); if (unlikely(!__xive_vm_h_eoi)) return H_NOT_AVAILABLE; return __xive_vm_h_eoi(vcpu, xirr); } else return xics_rm_h_eoi(vcpu, xirr); } #endif /* CONFIG_KVM_XICS */