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-rw-r--r--arch/powerpc/kvm/book3s_hv_builtin.c261
1 files changed, 261 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
new file mode 100644
index 000000000..ed2589d45
--- /dev/null
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -0,0 +1,261 @@
+/*
+ * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ *
+ * 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 <linux/cpu.h>
+#include <linux/kvm_host.h>
+#include <linux/preempt.h>
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/memblock.h>
+#include <linux/sizes.h>
+#include <linux/cma.h>
+#include <linux/bitops.h>
+
+#include <asm/cputable.h>
+#include <asm/kvm_ppc.h>
+#include <asm/kvm_book3s.h>
+#include <asm/archrandom.h>
+#include <asm/xics.h>
+#include <asm/dbell.h>
+#include <asm/cputhreads.h>
+
+#define KVM_CMA_CHUNK_ORDER 18
+
+/*
+ * 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(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));
+}
+EXPORT_SYMBOL_GPL(kvm_alloc_hpt);
+
+void kvm_release_hpt(struct page *page, unsigned long nr_pages)
+{
+ cma_release(kvm_cma, page, nr_pages);
+}
+EXPORT_SYMBOL_GPL(kvm_release_hpt);
+
+/**
+ * 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);
+ }
+}
+
+/*
+ * 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 = vcpu->arch.vcore;
+ 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(vcpu->arch.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(vcpu->arch.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)
+{
+ if (powernv_get_random_real_mode(&vcpu->arch.gpr[4]))
+ return H_SUCCESS;
+
+ return H_HARDWARE;
+}
+
+static inline void rm_writeb(unsigned long paddr, u8 val)
+{
+ __asm__ __volatile__("stbcix %0,0,%1"
+ : : "r" (val), "r" (paddr) : "memory");
+}
+
+/*
+ * Send an interrupt or message to another CPU.
+ * This can only be called in real mode.
+ * The caller needs to include any barrier needed to order writes
+ * to memory vs. the IPI/message.
+ */
+void kvmhv_rm_send_ipi(int cpu)
+{
+ unsigned long xics_phys;
+
+ /* 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())) {
+ unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER);
+ msg |= cpu_thread_in_core(cpu);
+ __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg));
+ return;
+ }
+
+ /* Else poke the target with an IPI */
+ xics_phys = paca[cpu].kvm_hstate.xics_phys;
+ rm_writeb(xics_phys + XICS_MFRR, 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;
+ int me, ee;
+
+ /* 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));
+}