References: bnc#808269 FATE#313605

# Commit d7dafa375bc13772e2e3274d975d544af4208939
# Date 2013-04-18 11:34:49 +0200
# Author Yang Zhang <yang.z.zhang@Intel.com>
# Committer Jan Beulich <jbeulich@suse.com>
VMX: Add posted interrupt supporting

Add the supporting of using posted interrupt to deliver interrupt.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Reviewed-by: Jun Nakajima <jun.nakajima@intel.com>
Acked-by: Keir Fraser <keir@xen.org>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com> (from a release perspective)

# Commit e4e1e0ecc023caf4cf3b87a4aa4d5e210760f4e8
# Date 2013-04-19 12:31:18 +0200
# Author Jan Beulich <jbeulich@suse.com>
# Committer Jan Beulich <jbeulich@suse.com>
VMX: adjust correct table when there's no posted interrupt support

The caller of start_vmx() will overwrite hvm_funcs, so there's no point
in adjusting that table in start_vmx().

Signed-off-by: Jan Beulich <jbeulich@suse.com>

Index: xen-4.2.4-testing/xen/arch/x86/hvm/vlapic.c
===================================================================
--- xen-4.2.4-testing.orig/xen/arch/x86/hvm/vlapic.c
+++ xen-4.2.4-testing/xen/arch/x86/hvm/vlapic.c
@@ -90,24 +90,6 @@ static unsigned int vlapic_lvt_mask[VLAP
     ((vlapic_get_reg(vlapic, APIC_LVTT) & APIC_TIMER_MODE_MASK) \
      == APIC_TIMER_MODE_TSC_DEADLINE)
 
-
-/*
- * Generic APIC bitmap vector update & search routines.
- */
-
-#define VEC_POS(v) ((v)%32)
-#define REG_POS(v) (((v)/32) * 0x10)
-#define vlapic_test_and_set_vector(vec, bitmap)                         \
-    test_and_set_bit(VEC_POS(vec),                                      \
-                     (unsigned long *)((bitmap) + REG_POS(vec)))
-#define vlapic_test_and_clear_vector(vec, bitmap)                       \
-    test_and_clear_bit(VEC_POS(vec),                                    \
-                       (unsigned long *)((bitmap) + REG_POS(vec)))
-#define vlapic_set_vector(vec, bitmap)                                  \
-    set_bit(VEC_POS(vec), (unsigned long *)((bitmap) + REG_POS(vec)))
-#define vlapic_clear_vector(vec, bitmap)                                \
-    clear_bit(VEC_POS(vec), (unsigned long *)((bitmap) + REG_POS(vec)))
-
 static int vlapic_find_highest_vector(void *bitmap)
 {
     uint32_t *word = bitmap;
Index: xen-4.2.4-testing/xen/arch/x86/hvm/vmx/vmx.c
===================================================================
--- xen-4.2.4-testing.orig/xen/arch/x86/hvm/vmx/vmx.c
+++ xen-4.2.4-testing/xen/arch/x86/hvm/vmx/vmx.c
@@ -56,6 +56,7 @@
 #include <asm/debugger.h>
 #include <asm/apic.h>
 #include <asm/hvm/nestedhvm.h>
+#include <asm/event.h>
 
 enum handler_return { HNDL_done, HNDL_unhandled, HNDL_exception_raised };
 
@@ -1613,6 +1614,60 @@ static void vmx_process_isr(int isr, str
     vmx_vmcs_exit(v);
 }
 
+static void __vmx_deliver_posted_interrupt(struct vcpu *v)
+{
+    bool_t running = v->is_running;
+
+    vcpu_unblock(v);
+    if ( running && (in_irq() || (v != current)) )
+    {
+        unsigned int cpu = v->processor;
+
+        if ( !test_and_set_bit(VCPU_KICK_SOFTIRQ, &softirq_pending(cpu))
+             && (cpu != smp_processor_id()) )
+            send_IPI_mask(cpumask_of(cpu), posted_intr_vector);
+    }
+}
+
+static void vmx_deliver_posted_intr(struct vcpu *v, u8 vector)
+{
+    if ( pi_test_and_set_pir(vector, &v->arch.hvm_vmx.pi_desc) )
+        return;
+
+    if ( unlikely(v->arch.hvm_vmx.eoi_exitmap_changed) )
+    {
+        /*
+         * If EOI exitbitmap needs to changed or notification vector
+         * can't be allocated, interrupt will not be injected till
+         * VMEntry as it used to be.
+         */
+        pi_set_on(&v->arch.hvm_vmx.pi_desc);
+    }
+    else if ( !pi_test_and_set_on(&v->arch.hvm_vmx.pi_desc) )
+    {
+        __vmx_deliver_posted_interrupt(v);
+        return;
+    }
+
+    vcpu_kick(v);
+}
+
+static void vmx_sync_pir_to_irr(struct vcpu *v)
+{
+    struct vlapic *vlapic = vcpu_vlapic(v);
+    unsigned int group, i;
+    DECLARE_BITMAP(pending_intr, NR_VECTORS);
+
+    if ( !pi_test_and_clear_on(&v->arch.hvm_vmx.pi_desc) )
+        return;
+
+    for ( group = 0; group < ARRAY_SIZE(pending_intr); group++ )
+        pending_intr[group] = pi_get_pir(&v->arch.hvm_vmx.pi_desc, group);
+
+    for_each_set_bit(i, pending_intr, NR_VECTORS)
+        vlapic_set_vector(i, &vlapic->regs->data[APIC_IRR]);
+}
+
 static struct hvm_function_table __read_mostly vmx_function_table = {
     .name                 = "VMX",
     .cpu_up_prepare       = vmx_cpu_up_prepare,
@@ -1663,6 +1718,8 @@ static struct hvm_function_table __read_
     .update_eoi_exit_bitmap = vmx_update_eoi_exit_bitmap,
     .virtual_intr_delivery_enabled = vmx_virtual_intr_delivery_enabled,
     .process_isr          = vmx_process_isr,
+    .deliver_posted_intr  = vmx_deliver_posted_intr,
+    .sync_pir_to_irr      = vmx_sync_pir_to_irr,
 };
 
 struct hvm_function_table * __init start_vmx(void)
@@ -1698,6 +1755,11 @@ struct hvm_function_table * __init start
 
     if ( cpu_has_vmx_posted_intr_processing )
         alloc_direct_apic_vector(&posted_intr_vector, event_check_interrupt);
+    else
+    {
+        vmx_function_table.deliver_posted_intr = NULL;
+        vmx_function_table.sync_pir_to_irr = NULL;
+    }
 
     setup_vmcs_dump();
 
Index: xen-4.2.4-testing/xen/include/asm-x86/bitops.h
===================================================================
--- xen-4.2.4-testing.orig/xen/include/asm-x86/bitops.h
+++ xen-4.2.4-testing/xen/include/asm-x86/bitops.h
@@ -367,6 +367,16 @@ static inline unsigned int __scanbit(uns
   ((off)+(__scanbit(~(((*(const unsigned long *)addr)) >> (off)), size))) : \
   __find_next_zero_bit(addr,size,off)))
 
+/**
+ * for_each_set_bit - iterate over every set bit in a memory region
+ * @bit: The integer iterator
+ * @addr: The address to base the search on
+ * @size: The maximum size to search
+ */
+#define for_each_set_bit(bit, addr, size)               \
+    for ( (bit) = find_first_bit(addr, size);           \
+          (bit) < (size);                               \
+          (bit) = find_next_bit(addr, size, (bit) + 1) )
 
 /**
  * find_first_set_bit - find the first set bit in @word
Index: xen-4.2.4-testing/xen/include/asm-x86/hvm/hvm.h
===================================================================
--- xen-4.2.4-testing.orig/xen/include/asm-x86/hvm/hvm.h
+++ xen-4.2.4-testing/xen/include/asm-x86/hvm/hvm.h
@@ -185,6 +185,8 @@ struct hvm_function_table {
     void (*update_eoi_exit_bitmap)(struct vcpu *v, u8 vector, u8 trig);
     int (*virtual_intr_delivery_enabled)(void);
     void (*process_isr)(int isr, struct vcpu *v);
+    void (*deliver_posted_intr)(struct vcpu *v, u8 vector);
+    void (*sync_pir_to_irr)(struct vcpu *v);
 };
 
 extern struct hvm_function_table hvm_funcs;
Index: xen-4.2.4-testing/xen/include/asm-x86/hvm/vlapic.h
===================================================================
--- xen-4.2.4-testing.orig/xen/include/asm-x86/hvm/vlapic.h
+++ xen-4.2.4-testing/xen/include/asm-x86/hvm/vlapic.h
@@ -54,6 +54,21 @@
 #define vlapic_x2apic_mode(vlapic)                              \
     ((vlapic)->hw.apic_base_msr & MSR_IA32_APICBASE_EXTD)
 
+/*
+ * Generic APIC bitmap vector update & search routines.
+ */
+
+#define VEC_POS(v) ((v) % 32)
+#define REG_POS(v) (((v) / 32) * 0x10)
+#define vlapic_test_and_set_vector(vec, bitmap)                         \
+    test_and_set_bit(VEC_POS(vec), (uint32_t *)((bitmap) + REG_POS(vec)))
+#define vlapic_test_and_clear_vector(vec, bitmap)                       \
+    test_and_clear_bit(VEC_POS(vec), (uint32_t *)((bitmap) + REG_POS(vec)))
+#define vlapic_set_vector(vec, bitmap)                                  \
+    set_bit(VEC_POS(vec), (uint32_t *)((bitmap) + REG_POS(vec)))
+#define vlapic_clear_vector(vec, bitmap)                                \
+    clear_bit(VEC_POS(vec), (uint32_t *)((bitmap) + REG_POS(vec)))
+
 struct vlapic {
     struct hvm_hw_lapic      hw;
     struct hvm_hw_lapic_regs *regs;
Index: xen-4.2.4-testing/xen/include/asm-x86/hvm/vmx/vmx.h
===================================================================
--- xen-4.2.4-testing.orig/xen/include/asm-x86/hvm/vmx/vmx.h
+++ xen-4.2.4-testing/xen/include/asm-x86/hvm/vmx/vmx.h
@@ -71,6 +71,31 @@ void vmx_update_debug_state(struct vcpu
 void vmx_update_exception_bitmap(struct vcpu *v);
 void vmx_update_cpu_exec_control(struct vcpu *v);
 
+#define POSTED_INTR_ON  0
+static inline int pi_test_and_set_pir(int vector, struct pi_desc *pi_desc)
+{
+    return test_and_set_bit(vector, pi_desc->pir);
+}
+
+static inline int pi_test_and_set_on(struct pi_desc *pi_desc)
+{
+    return test_and_set_bit(POSTED_INTR_ON, &pi_desc->control);
+}
+
+static inline void pi_set_on(struct pi_desc *pi_desc)
+{
+    set_bit(POSTED_INTR_ON, &pi_desc->control);
+}
+
+static inline int pi_test_and_clear_on(struct pi_desc *pi_desc)
+{
+    return test_and_clear_bit(POSTED_INTR_ON, &pi_desc->control);
+}
+
+static inline unsigned long pi_get_pir(struct pi_desc *pi_desc, int group)
+{
+    return xchg(&pi_desc->pir[group], 0);
+}
 
 /*
  * Exit Reasons
