8 files changed, 147 insertions, 61 deletions

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index e87ecaa2c569..d5bc3750616e 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -38,13 +38,6 @@ struct sca_block {
         struct sca_entry cpu[64];
 } __attribute__((packed));
 
-#define KVM_NR_PAGE_SIZES 2
-#define KVM_HPAGE_GFN_SHIFT(x) (((x) - 1) * 8)
-#define KVM_HPAGE_SHIFT(x) (PAGE_SHIFT + KVM_HPAGE_GFN_SHIFT(x))
-#define KVM_HPAGE_SIZE(x) (1UL << KVM_HPAGE_SHIFT(x))
-#define KVM_HPAGE_MASK(x)       (~(KVM_HPAGE_SIZE(x) - 1))
-#define KVM_PAGES_PER_HPAGE(x)  (KVM_HPAGE_SIZE(x) / PAGE_SIZE)
-
 #define CPUSTAT_STOPPED    0x80000000
 #define CPUSTAT_WAIT       0x10000000
 #define CPUSTAT_ECALL_PEND 0x08000000
@@ -220,7 +213,6 @@ struct kvm_s390_interrupt_info {
 /* for local_interrupt.action_flags */
 #define ACTION_STORE_ON_STOP            (1<<0)
 #define ACTION_STOP_ON_STOP             (1<<1)
-#define ACTION_RELOADVCPU_ON_STOP       (1<<2)
 
 struct kvm_s390_local_interrupt {
         spinlock_t lock;
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index 3a74d8af0d69..78d967f180f4 100644
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -107,14 +107,13 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
 
 static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)
 {
-        int ret, idx;
+        int ret;
 
         /* No virtio-ccw notification? Get out quickly. */
         if (!vcpu->kvm->arch.css_support ||
             (vcpu->run->s.regs.gprs[1] != KVM_S390_VIRTIO_CCW_NOTIFY))
                 return -EOPNOTSUPP;
 
-        idx = srcu_read_lock(&vcpu->kvm->srcu);
         /*
          * The layout is as follows:
          * - gpr 2 contains the subchannel id (passed as addr)
@@ -125,7 +124,6 @@ static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)
                                       vcpu->run->s.regs.gprs[2],
                                       8, &vcpu->run->s.regs.gprs[3],
                                       vcpu->run->s.regs.gprs[4]);
-        srcu_read_unlock(&vcpu->kvm->srcu, idx);
 
         /*
          * Return cookie in gpr 2, but don't overwrite the register if the
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index 99d789e8a018..374a439ccc60 100644
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -18,20 +18,27 @@
 #include <asm/uaccess.h>
 #include "kvm-s390.h"
 
+/* Convert real to absolute address by applying the prefix of the CPU */
+static inline unsigned long kvm_s390_real_to_abs(struct kvm_vcpu *vcpu,
+                                                 unsigned long gaddr)
+{
+        unsigned long prefix  = vcpu->arch.sie_block->prefix;
+        if (gaddr < 2 * PAGE_SIZE)
+                gaddr += prefix;
+        else if (gaddr >= prefix && gaddr < prefix + 2 * PAGE_SIZE)
+                gaddr -= prefix;
+        return gaddr;
+}
+
 static inline void __user *__gptr_to_uptr(struct kvm_vcpu *vcpu,
                                           void __user *gptr,
                                           int prefixing)
 {
-        unsigned long prefix  = vcpu->arch.sie_block->prefix;
         unsigned long gaddr = (unsigned long) gptr;
         unsigned long uaddr;
 
-        if (prefixing) {
-                if (gaddr < 2 * PAGE_SIZE)
-                        gaddr += prefix;
-                else if ((gaddr >= prefix) && (gaddr < prefix + 2 * PAGE_SIZE))
-                        gaddr -= prefix;
-        }
+        if (prefixing)
+                gaddr = kvm_s390_real_to_abs(vcpu, gaddr);
         uaddr = gmap_fault(gaddr, vcpu->arch.gmap);
         if (IS_ERR_VALUE(uaddr))
                 uaddr = -EFAULT;
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index 5ee56e5acc23..5ddbbde6f65c 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -62,12 +62,6 @@ static int handle_stop(struct kvm_vcpu *vcpu)
 
         trace_kvm_s390_stop_request(vcpu->arch.local_int.action_bits);
 
-        if (vcpu->arch.local_int.action_bits & ACTION_RELOADVCPU_ON_STOP) {
-                vcpu->arch.local_int.action_bits &= ~ACTION_RELOADVCPU_ON_STOP;
-                rc = SIE_INTERCEPT_RERUNVCPU;
-                vcpu->run->exit_reason = KVM_EXIT_INTR;
-        }
-
         if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) {
                 atomic_set_mask(CPUSTAT_STOPPED,
                                 &vcpu->arch.sie_block->cpuflags);
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 7f1f7ac5cf7f..5f79d2d79ca7 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -436,6 +436,7 @@ int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
         hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL);
         VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime);
 no_timer:
+        srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
         spin_lock(&vcpu->arch.local_int.float_int->lock);
         spin_lock_bh(&vcpu->arch.local_int.lock);
         add_wait_queue(&vcpu->wq, &wait);
@@ -455,6 +456,8 @@ no_timer:
         remove_wait_queue(&vcpu->wq, &wait);
         spin_unlock_bh(&vcpu->arch.local_int.lock);
         spin_unlock(&vcpu->arch.local_int.float_int->lock);
+        vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+
         hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
         return 0;
 }
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index ed8064cb5c49..569494e01ec6 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -695,9 +695,9 @@ static int kvm_s390_handle_requests(struct kvm_vcpu *vcpu)
         return 0;
 }
 
-static int __vcpu_run(struct kvm_vcpu *vcpu)
+static int vcpu_pre_run(struct kvm_vcpu *vcpu)
 {
-        int rc;
+        int rc, cpuflags;
 
         memcpy(&vcpu->arch.sie_block->gg14, &vcpu->run->s.regs.gprs[14], 16);
 
@@ -715,28 +715,24 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
                 return rc;
 
         vcpu->arch.sie_block->icptcode = 0;
-        VCPU_EVENT(vcpu, 6, "entering sie flags %x",
-                   atomic_read(&vcpu->arch.sie_block->cpuflags));
-        trace_kvm_s390_sie_enter(vcpu,
-                                 atomic_read(&vcpu->arch.sie_block->cpuflags));
+        cpuflags = atomic_read(&vcpu->arch.sie_block->cpuflags);
+        VCPU_EVENT(vcpu, 6, "entering sie flags %x", cpuflags);
+        trace_kvm_s390_sie_enter(vcpu, cpuflags);
 
-        /*
-         * As PF_VCPU will be used in fault handler, between guest_enter
-         * and guest_exit should be no uaccess.
-         */
-        preempt_disable();
-        kvm_guest_enter();
-        preempt_enable();
-        rc = sie64a(vcpu->arch.sie_block, vcpu->run->s.regs.gprs);
-        kvm_guest_exit();
+        return 0;
+}
+
+static int vcpu_post_run(struct kvm_vcpu *vcpu, int exit_reason)
+{
+        int rc;
 
         VCPU_EVENT(vcpu, 6, "exit sie icptcode %d",
                    vcpu->arch.sie_block->icptcode);
         trace_kvm_s390_sie_exit(vcpu, vcpu->arch.sie_block->icptcode);
 
-        if (rc > 0)
+        if (exit_reason >= 0) {
                 rc = 0;
-        if (rc < 0) {
+        } else {
                 if (kvm_is_ucontrol(vcpu->kvm)) {
                         rc = SIE_INTERCEPT_UCONTROL;
                 } else {
@@ -747,6 +743,49 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
         }
 
         memcpy(&vcpu->run->s.regs.gprs[14], &vcpu->arch.sie_block->gg14, 16);
+
+        if (rc == 0) {
+                if (kvm_is_ucontrol(vcpu->kvm))
+                        rc = -EOPNOTSUPP;
+                else
+                        rc = kvm_handle_sie_intercept(vcpu);
+        }
+
+        return rc;
+}
+
+static int __vcpu_run(struct kvm_vcpu *vcpu)
+{
+        int rc, exit_reason;
+
+        /*
+         * We try to hold kvm->srcu during most of vcpu_run (except when run-
+         * ning the guest), so that memslots (and other stuff) are protected
+         */
+        vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+
+        do {
+                rc = vcpu_pre_run(vcpu);
+                if (rc)
+                        break;
+
+                srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
+                /*
+                 * As PF_VCPU will be used in fault handler, between
+                 * guest_enter and guest_exit should be no uaccess.
+                 */
+                preempt_disable();
+                kvm_guest_enter();
+                preempt_enable();
+                exit_reason = sie64a(vcpu->arch.sie_block,
+                                     vcpu->run->s.regs.gprs);
+                kvm_guest_exit();
+                vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+
+                rc = vcpu_post_run(vcpu, exit_reason);
+        } while (!signal_pending(current) && !rc);
+
+        srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
         return rc;
 }
 
@@ -755,7 +794,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
         int rc;
         sigset_t sigsaved;
 
-rerun_vcpu:
         if (vcpu->sigset_active)
                 sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 
@@ -788,19 +826,7 @@ rerun_vcpu:
         }
 
         might_fault();
-
-        do {
-                rc = __vcpu_run(vcpu);
-                if (rc)
-                        break;
-                if (kvm_is_ucontrol(vcpu->kvm))
-                        rc = -EOPNOTSUPP;
-                else
-                        rc = kvm_handle_sie_intercept(vcpu);
-        } while (!signal_pending(current) && !rc);
-
-        if (rc == SIE_INTERCEPT_RERUNVCPU)
-                goto rerun_vcpu;
+        rc = __vcpu_run(vcpu);
 
         if (signal_pending(current) && !rc) {
                 kvm_run->exit_reason = KVM_EXIT_INTR;
@@ -958,6 +984,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 {
         struct kvm_vcpu *vcpu = filp->private_data;
         void __user *argp = (void __user *)arg;
+        int idx;
         long r;
 
         switch (ioctl) {
@@ -971,7 +998,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
                 break;
         }
         case KVM_S390_STORE_STATUS:
+                idx = srcu_read_lock(&vcpu->kvm->srcu);
                 r = kvm_s390_vcpu_store_status(vcpu, arg);
+                srcu_read_unlock(&vcpu->kvm->srcu, idx);
                 break;
         case KVM_S390_SET_INITIAL_PSW: {
                 psw_t psw;
@@ -1067,12 +1096,13 @@ int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
         return VM_FAULT_SIGBUS;
 }
 
-void kvm_arch_free_memslot(struct kvm_memory_slot *free,
+void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
                            struct kvm_memory_slot *dont)
 {
 }
 
-int kvm_arch_create_memslot(struct kvm_memory_slot *slot, unsigned long npages)
+int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
+                            unsigned long npages)
 {
         return 0;
 }
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index dc99f1ca4267..b44912a32949 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -28,8 +28,7 @@ typedef int (*intercept_handler_t)(struct kvm_vcpu *vcpu);
 extern unsigned long *vfacilities;
 
 /* negativ values are error codes, positive values for internal conditions */
-#define SIE_INTERCEPT_RERUNVCPU         (1<<0)
-#define SIE_INTERCEPT_UCONTROL          (1<<1)
+#define SIE_INTERCEPT_UCONTROL          (1<<0)
 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu);
 
 #define VM_EVENT(d_kvm, d_loglevel, d_string, d_args...)\
@@ -91,8 +90,10 @@ static inline void kvm_s390_get_base_disp_sse(struct kvm_vcpu *vcpu,
 
 static inline void kvm_s390_get_regs_rre(struct kvm_vcpu *vcpu, int *r1, int *r2)
 {
-        *r1 = (vcpu->arch.sie_block->ipb & 0x00f00000) >> 20;
-        *r2 = (vcpu->arch.sie_block->ipb & 0x000f0000) >> 16;
+        if (r1)
+                *r1 = (vcpu->arch.sie_block->ipb & 0x00f00000) >> 20;
+        if (r2)
+                *r2 = (vcpu->arch.sie_block->ipb & 0x000f0000) >> 16;
 }
 
 static inline u64 kvm_s390_get_base_disp_rsy(struct kvm_vcpu *vcpu)
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 59200ee275e5..2440602e6df1 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -30,6 +30,38 @@
 #include "kvm-s390.h"
 #include "trace.h"
 
+/* Handle SCK (SET CLOCK) interception */
+static int handle_set_clock(struct kvm_vcpu *vcpu)
+{
+        struct kvm_vcpu *cpup;
+        s64 hostclk, val;
+        u64 op2;
+        int i;
+
+        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
+                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
+
+        op2 = kvm_s390_get_base_disp_s(vcpu);
+        if (op2 & 7)    /* Operand must be on a doubleword boundary */
+                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+        if (get_guest(vcpu, val, (u64 __user *) op2))
+                return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+
+        if (store_tod_clock(&hostclk)) {
+                kvm_s390_set_psw_cc(vcpu, 3);
+                return 0;
+        }
+        val = (val - hostclk) & ~0x3fUL;
+
+        mutex_lock(&vcpu->kvm->lock);
+        kvm_for_each_vcpu(i, cpup, vcpu->kvm)
+                cpup->arch.sie_block->epoch = val;
+        mutex_unlock(&vcpu->kvm->lock);
+
+        kvm_s390_set_psw_cc(vcpu, 0);
+        return 0;
+}
+
 static int handle_set_prefix(struct kvm_vcpu *vcpu)
 {
         u64 operand2;
@@ -128,6 +160,33 @@ static int handle_skey(struct kvm_vcpu *vcpu)
         return 0;
 }
 
+static int handle_test_block(struct kvm_vcpu *vcpu)
+{
+        unsigned long hva;
+        gpa_t addr;
+        int reg2;
+
+        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
+                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
+
+        kvm_s390_get_regs_rre(vcpu, NULL, &reg2);
+        addr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK;
+        addr = kvm_s390_real_to_abs(vcpu, addr);
+
+        hva = gfn_to_hva(vcpu->kvm, gpa_to_gfn(addr));
+        if (kvm_is_error_hva(hva))
+                return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+        /*
+         * We don't expect errors on modern systems, and do not care
+         * about storage keys (yet), so let's just clear the page.
+         */
+        if (clear_user((void __user *)hva, PAGE_SIZE) != 0)
+                return -EFAULT;
+        kvm_s390_set_psw_cc(vcpu, 0);
+        vcpu->run->s.regs.gprs[0] = 0;
+        return 0;
+}
+
 static int handle_tpi(struct kvm_vcpu *vcpu)
 {
         struct kvm_s390_interrupt_info *inti;
@@ -438,12 +497,14 @@ out_exception:
 
 static const intercept_handler_t b2_handlers[256] = {
         [0x02] = handle_stidp,
+        [0x04] = handle_set_clock,
         [0x10] = handle_set_prefix,
         [0x11] = handle_store_prefix,
         [0x12] = handle_store_cpu_address,
         [0x29] = handle_skey,
         [0x2a] = handle_skey,
         [0x2b] = handle_skey,
+        [0x2c] = handle_test_block,
         [0x30] = handle_io_inst,
         [0x31] = handle_io_inst,
         [0x32] = handle_io_inst,