Merge branch 'upstream/core' into upstream/xen

* upstream/core:
  xen/panic: use xen_reboot and fix smp_send_stop
  Xen: register panic notifier to take crashes of xen guests on panic
  xen: support large numbers of CPUs with vcpu info placement
  xen: drop xen_sched_clock in favour of using plain wallclock time
  pvops: do not notify callers from register_xenstore_notifier
  xen: make sure pages are really part of domain before freeing
  xen: release unused free memory

6 files changed, 112 insertions, 49 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 65d8d79b46a8..3c4da8bee06f 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -97,6 +97,14 @@ struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
  */
 static int have_vcpu_info_placement = 1;
 
+static void clamp_max_cpus(void)
+{
+#ifdef CONFIG_SMP
+        if (setup_max_cpus > MAX_VIRT_CPUS)
+                setup_max_cpus = MAX_VIRT_CPUS;
+#endif
+}
+
 static void xen_vcpu_setup(int cpu)
 {
         struct vcpu_register_vcpu_info info;
@@ -104,13 +112,17 @@ static void xen_vcpu_setup(int cpu)
         struct vcpu_info *vcpup;
 
         BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
-        per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
 
-        if (!have_vcpu_info_placement)
-                return;         /* already tested, not available */
+        if (cpu < MAX_VIRT_CPUS)
+                per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
 
-        vcpup = &per_cpu(xen_vcpu_info, cpu);
+        if (!have_vcpu_info_placement) {
+                if (cpu >= MAX_VIRT_CPUS)
+                        clamp_max_cpus();
+                return;
+        }
 
+        vcpup = &per_cpu(xen_vcpu_info, cpu);
         info.mfn = arbitrary_virt_to_mfn(vcpup);
         info.offset = offset_in_page(vcpup);
 
@@ -125,6 +137,7 @@ static void xen_vcpu_setup(int cpu)
         if (err) {
                 printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err);
                 have_vcpu_info_placement = 0;
+                clamp_max_cpus();
         } else {
                 /* This cpu is using the registered vcpu info, even if
                    later ones fail to. */
@@ -731,7 +744,6 @@ static void set_xen_basic_apic_ops(void)
 
 #endif
 
-
 static void xen_clts(void)
 {
         struct multicall_space mcs;
@@ -927,7 +939,7 @@ static const struct pv_init_ops xen_init_ops __initdata = {
 };
 
 static const struct pv_time_ops xen_time_ops __initdata = {
-        .sched_clock = xen_sched_clock,
+        .sched_clock = xen_clocksource_read,
 };
 
 static const struct pv_cpu_ops xen_cpu_ops __initdata = {
@@ -1028,6 +1040,23 @@ static void xen_crash_shutdown(struct pt_regs *regs)
         xen_reboot(SHUTDOWN_crash);
 }
 
+static int
+xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+        xen_reboot(SHUTDOWN_crash);
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block xen_panic_block = {
+        .notifier_call= xen_panic_event,
+};
+
+int xen_panic_handler_init(void)
+{
+        atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block);
+        return 0;
+}
+
 static const struct machine_ops __initdata xen_machine_ops = {
         .restart = xen_restart,
         .halt = xen_machine_halt,
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index ad0047f47cd4..328b00305426 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -20,6 +20,7 @@
 #include <xen/page.h>
 #include <xen/interface/callback.h>
 #include <xen/interface/physdev.h>
+#include <xen/interface/memory.h>
 #include <xen/features.h>
 
 #include "xen-ops.h"
@@ -32,6 +33,73 @@ extern void xen_sysenter_target(void);
 extern void xen_syscall_target(void);
 extern void xen_syscall32_target(void);
 
+static unsigned long __init xen_release_chunk(phys_addr_t start_addr,
+                                              phys_addr_t end_addr)
+{
+        struct xen_memory_reservation reservation = {
+                .address_bits = 0,
+                .extent_order = 0,
+                .domid        = DOMID_SELF
+        };
+        unsigned long start, end;
+        unsigned long len = 0;
+        unsigned long pfn;
+        int ret;
+
+        start = PFN_UP(start_addr);
+        end = PFN_DOWN(end_addr);
+
+        if (end <= start)
+                return 0;
+
+        printk(KERN_INFO "xen_release_chunk: looking at area pfn %lx-%lx: ",
+               start, end);
+        for(pfn = start; pfn < end; pfn++) {
+                unsigned long mfn = pfn_to_mfn(pfn);
+
+                /* Make sure pfn exists to start with */
+                if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn)
+                        continue;
+
+                set_xen_guest_handle(reservation.extent_start, &mfn);
+                reservation.nr_extents = 1;
+
+                ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
+                                           &reservation);
+                WARN(ret != 1, "Failed to release memory %lx-%lx err=%d\n",
+                     start, end, ret);
+                if (ret == 1) {
+                        set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
+                        len++;
+                }
+        }
+        printk(KERN_CONT "%ld pages freed\n", len);
+
+        return len;
+}
+
+static unsigned long __init xen_return_unused_memory(unsigned long max_pfn,
+                                                     const struct e820map *e820)
+{
+        phys_addr_t max_addr = PFN_PHYS(max_pfn);
+        phys_addr_t last_end = 0;
+        unsigned long released = 0;
+        int i;
+
+        for (i = 0; i < e820->nr_map && last_end < max_addr; i++) {
+                phys_addr_t end = e820->map[i].addr;
+                end = min(max_addr, end);
+
+                released += xen_release_chunk(last_end, end);
+                last_end = e820->map[i].addr + e820->map[i].size;
+        }
+
+        if (last_end < max_addr)
+                released += xen_release_chunk(last_end, max_addr);
+
+        printk(KERN_INFO "released %ld pages of unused memory\n", released);
+        return released;
+}
 
 /**
  * machine_specific_memory_setup - Hook for machine specific memory setup.
@@ -67,6 +135,8 @@ char * __init xen_memory_setup(void)
 
         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 
+        xen_return_unused_memory(xen_start_info->nr_pages, &e820);
+
         return "Xen";
 }
 
@@ -156,6 +226,8 @@ void __init xen_arch_setup(void)
         struct physdev_set_iopl set_iopl;
         int rc;
 
+        xen_panic_handler_init();
+
         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
 
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index a29693fd3138..25f232b18a82 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -394,6 +394,8 @@ static void stop_self(void *v)
         load_cr3(swapper_pg_dir);
         /* should set up a minimal gdt */
 
+        set_cpu_online(cpu, false);
+
         HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
         BUG();
 }
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index b3c6c59ed302..a86df42e46ad 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -155,45 +155,6 @@ static void do_stolen_accounting(void)
         account_idle_ticks(ticks);
 }
 
-/*
- * Xen sched_clock implementation.  Returns the number of unstolen
- * nanoseconds, which is nanoseconds the VCPU spent in RUNNING+BLOCKED
- * states.
- */
-unsigned long long xen_sched_clock(void)
-{
-        struct vcpu_runstate_info state;
-        cycle_t now;
-        u64 ret;
-        s64 offset;
-
-        /*
-         * Ideally sched_clock should be called on a per-cpu basis
-         * anyway, so preempt should already be disabled, but that's
-         * not current practice at the moment.
-         */
-        preempt_disable();
-
-        now = xen_clocksource_read();
-
-        get_runstate_snapshot(&state);
-
-        WARN_ON(state.state != RUNSTATE_running);
-
-        offset = now - state.state_entry_time;
-        if (offset < 0)
-                offset = 0;
-
-        ret = state.time[RUNSTATE_blocked] +
-                state.time[RUNSTATE_running] +
-                offset;
-
-        preempt_enable();
-
-        return ret;
-}
-
-
 /* Get the TSC speed from Xen */
 unsigned long xen_tsc_khz(void)
 {
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index f9153a300bce..00d59d608edf 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -101,4 +101,6 @@ void xen_sysret32(void);
 void xen_sysret64(void);
 void xen_adjust_exception_frame(void);
 
+extern int xen_panic_handler_init(void);
+
 #endif /* XEN_OPS_H */
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 3479332113e9..abc12426ef0a 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -752,10 +752,7 @@ int register_xenstore_notifier(struct notifier_block *nb)
 {
         int ret = 0;
 
-        if (xenstored_ready > 0)
-                ret = nb->notifier_call(nb, 0, NULL);
-        else
-                blocking_notifier_chain_register(&xenstore_chain, nb);
+        blocking_notifier_chain_register(&xenstore_chain, nb);
 
         return ret;
 }