1 files changed, 63 insertions, 0 deletions

diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 275425142bb7..c42aa55b885f 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -22,6 +22,7 @@
 #include <asm/kvm_ppc.h>
 #include <asm/kvm_book3s.h>
 #include <asm/archrandom.h>
+#include <asm/xics.h>
 
 #define KVM_CMA_CHUNK_ORDER     18
 
@@ -184,3 +185,65 @@ long kvmppc_h_random(struct kvm_vcpu *vcpu)
 
         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 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;
+
+        /* Poke the target */
+        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));
+}