KVM: s390: optimize float int lock: spin_lock_bh --> spin_lock

[firefly-linux-kernel-4.4.55.git] / arch / s390 / kvm / kvm-s390.c

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index f4d56e9939c90949c1e886eaabf6cc7d35cab858..36c654d2d64a2341ef4f00b183908665f068cf8a 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -15,6 +15,7 @@
 #include <linux/compiler.h>
 #include <linux/err.h>
 #include <linux/fs.h>
+#include <linux/hrtimer.h>
 #include <linux/init.h>
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
@@ -283,8 +284,10 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
        vcpu->arch.sie_block->gmsor = vcpu->kvm->arch.guest_origin;
        vcpu->arch.sie_block->ecb   = 2;
        vcpu->arch.sie_block->eca   = 0xC1002001U;
-       setup_timer(&vcpu->arch.ckc_timer, kvm_s390_idle_wakeup,
-                (unsigned long) vcpu);
+       hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
+       tasklet_init(&vcpu->arch.tasklet, kvm_s390_tasklet,
+                    (unsigned long) vcpu);
+       vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;
        get_cpu_id(&vcpu->arch.cpu_id);
        vcpu->arch.cpu_id.version = 0xff;
        return 0;
@@ -315,11 +318,11 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
        spin_lock_init(&vcpu->arch.local_int.lock);
        INIT_LIST_HEAD(&vcpu->arch.local_int.list);
        vcpu->arch.local_int.float_int = &kvm->arch.float_int;
-       spin_lock_bh(&kvm->arch.float_int.lock);
+       spin_lock(&kvm->arch.float_int.lock);
        kvm->arch.float_int.local_int[id] = &vcpu->arch.local_int;
        init_waitqueue_head(&vcpu->arch.local_int.wq);
        vcpu->arch.local_int.cpuflags = &vcpu->arch.sie_block->cpuflags;
-       spin_unlock_bh(&kvm->arch.float_int.lock);
+       spin_unlock(&kvm->arch.float_int.lock);
 
        rc = kvm_vcpu_init(vcpu, kvm, id);
        if (rc)
@@ -657,6 +660,8 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
                                struct kvm_memory_slot old,
                                int user_alloc)
 {
+       int i;
+
        /* A few sanity checks. We can have exactly one memory slot which has
           to start at guest virtual zero and which has to be located at a
           page boundary in userland and which has to end at a page boundary.
@@ -664,7 +669,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
           vmas. It is okay to mmap() and munmap() stuff in this slot after
           doing this call at any time */
 
-       if (mem->slot)
+       if (mem->slot || kvm->arch.guest_memsize)
                return -EINVAL;
 
        if (mem->guest_phys_addr)
@@ -676,15 +681,39 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
        if (mem->memory_size & (PAGE_SIZE - 1))
                return -EINVAL;
 
+       if (!user_alloc)
+               return -EINVAL;
+
+       /* lock all vcpus */
+       for (i = 0; i < KVM_MAX_VCPUS; ++i) {
+               if (!kvm->vcpus[i])
+                       continue;
+               if (!mutex_trylock(&kvm->vcpus[i]->mutex))
+                       goto fail_out;
+       }
+
        kvm->arch.guest_origin = mem->userspace_addr;
        kvm->arch.guest_memsize = mem->memory_size;
 
-       /* FIXME: we do want to interrupt running CPUs and update their memory
-          configuration now to avoid race conditions. But hey, changing the
-          memory layout while virtual CPUs are running is usually bad
-          programming practice. */
+       /* update sie control blocks, and unlock all vcpus */
+       for (i = 0; i < KVM_MAX_VCPUS; ++i) {
+               if (kvm->vcpus[i]) {
+                       kvm->vcpus[i]->arch.sie_block->gmsor =
+                               kvm->arch.guest_origin;
+                       kvm->vcpus[i]->arch.sie_block->gmslm =
+                               kvm->arch.guest_memsize +
+                               kvm->arch.guest_origin +
+                               VIRTIODESCSPACE - 1ul;
+                       mutex_unlock(&kvm->vcpus[i]->mutex);
+               }
+       }
 
        return 0;
+
+fail_out:
+       for (; i >= 0; i--)
+               mutex_unlock(&kvm->vcpus[i]->mutex);
+       return -EINVAL;
 }
 
 void kvm_arch_flush_shadow(struct kvm *kvm)