VMX: convert EOI exit bitmap to a proper bitmap

... allowing bitmap operations to be used on it, making things
consistent with struct pi_desc's pir field, and shrinking overall
source code size.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/arch/x86/hvm/vmx/intr.c
+++ b/xen/arch/x86/hvm/vmx/intr.c
@@ -280,6 +280,7 @@ void vmx_intr_assist(void)
               intack.source != hvm_intsrc_vector )
     {
         unsigned long status = __vmread(GUEST_INTR_STATUS);
+        unsigned int i, n;
 
        /*
         * Set eoi_exit_bitmap for periodic timer interrup to cause EOI-induced VM
@@ -294,14 +295,13 @@ void vmx_intr_assist(void)
         status |= VMX_GUEST_INTR_STATUS_SUBFIELD_BITMASK &
                     intack.vector;
         __vmwrite(GUEST_INTR_STATUS, status);
-        if (v->arch.hvm_vmx.eoi_exitmap_changed) {
-#define UPDATE_EOI_EXITMAP(v, e) {                             \
-        if (test_and_clear_bit(e, &v->arch.hvm_vmx.eoi_exitmap_changed)) {      \
-                __vmwrite(EOI_EXIT_BITMAP##e, v->arch.hvm_vmx.eoi_exit_bitmap[e]);}}
-                UPDATE_EOI_EXITMAP(v, 0);
-                UPDATE_EOI_EXITMAP(v, 1);
-                UPDATE_EOI_EXITMAP(v, 2);
-                UPDATE_EOI_EXITMAP(v, 3);
+
+        n = ARRAY_SIZE(v->arch.hvm_vmx.eoi_exit_bitmap);
+        while ( (i = find_first_bit(&v->arch.hvm_vmx.eoi_exitmap_changed,
+                                    n)) < n )
+        {
+            clear_bit(i, &v->arch.hvm_vmx.eoi_exitmap_changed);
+            __vmwrite(EOI_EXIT_BITMAP(i), v->arch.hvm_vmx.eoi_exit_bitmap[i]);
         }
 
         pt_intr_post(v, intack);
--- a/xen/arch/x86/hvm/vmx/vmcs.c
+++ b/xen/arch/x86/hvm/vmx/vmcs.c
@@ -915,15 +915,12 @@ static int construct_vmcs(struct vcpu *v
 
     if ( cpu_has_vmx_virtual_intr_delivery )
     {
+        unsigned int i;
+
         /* EOI-exit bitmap */
-        v->arch.hvm_vmx.eoi_exit_bitmap[0] = (uint64_t)0;
-        __vmwrite(EOI_EXIT_BITMAP0, v->arch.hvm_vmx.eoi_exit_bitmap[0]);
-        v->arch.hvm_vmx.eoi_exit_bitmap[1] = (uint64_t)0;
-        __vmwrite(EOI_EXIT_BITMAP1, v->arch.hvm_vmx.eoi_exit_bitmap[1]);
-        v->arch.hvm_vmx.eoi_exit_bitmap[2] = (uint64_t)0;
-        __vmwrite(EOI_EXIT_BITMAP2, v->arch.hvm_vmx.eoi_exit_bitmap[2]);
-        v->arch.hvm_vmx.eoi_exit_bitmap[3] = (uint64_t)0;
-        __vmwrite(EOI_EXIT_BITMAP3, v->arch.hvm_vmx.eoi_exit_bitmap[3]);
+        bitmap_zero(v->arch.hvm_vmx.eoi_exit_bitmap, NR_VECTORS);
+        for ( i = 0; i < ARRAY_SIZE(v->arch.hvm_vmx.eoi_exit_bitmap); ++i )
+            __vmwrite(EOI_EXIT_BITMAP(i), 0);
 
         /* Initialise Guest Interrupt Status (RVI and SVI) to 0 */
         __vmwrite(GUEST_INTR_STATUS, 0);
@@ -1171,26 +1168,16 @@ int vmx_add_host_load_msr(u32 msr)
 
 void vmx_set_eoi_exit_bitmap(struct vcpu *v, u8 vector)
 {
-    int index, offset, changed;
-
-    index = vector >> 6; 
-    offset = vector & 63;
-    changed = !test_and_set_bit(offset,
-                  (uint64_t *)&v->arch.hvm_vmx.eoi_exit_bitmap[index]);
-    if (changed)
-        set_bit(index, &v->arch.hvm_vmx.eoi_exitmap_changed);
+    if ( !test_and_set_bit(vector, v->arch.hvm_vmx.eoi_exit_bitmap) )
+        set_bit(vector / BITS_PER_LONG,
+                &v->arch.hvm_vmx.eoi_exitmap_changed);
 }
 
 void vmx_clear_eoi_exit_bitmap(struct vcpu *v, u8 vector)
 {
-    int index, offset, changed;
-
-    index = vector >> 6; 
-    offset = vector & 63;
-    changed = test_and_clear_bit(offset,
-                  (uint64_t *)&v->arch.hvm_vmx.eoi_exit_bitmap[index]);
-    if (changed)
-        set_bit(index, &v->arch.hvm_vmx.eoi_exitmap_changed);
+    if ( test_and_clear_bit(vector, v->arch.hvm_vmx.eoi_exit_bitmap) )
+        set_bit(vector / BITS_PER_LONG,
+                &v->arch.hvm_vmx.eoi_exitmap_changed);
 }
 
 int vmx_create_vmcs(struct vcpu *v)
--- a/xen/include/asm-x86/hvm/vmx/vmcs.h
+++ b/xen/include/asm-x86/hvm/vmx/vmcs.h
@@ -118,8 +118,8 @@ struct arch_vmx_struct {
     unsigned int         host_msr_count;
     struct vmx_msr_entry *host_msr_area;
 
-    uint32_t             eoi_exitmap_changed;
-    uint64_t             eoi_exit_bitmap[4];
+    unsigned long        eoi_exitmap_changed;
+    DECLARE_BITMAP(eoi_exit_bitmap, NR_VECTORS);
     struct pi_desc       pi_desc;
 
     unsigned long        host_cr0;
@@ -331,13 +331,7 @@ enum vmcs_field {
     EPT_POINTER                     = 0x0000201a,
     EPT_POINTER_HIGH                = 0x0000201b,
     EOI_EXIT_BITMAP0                = 0x0000201c,
-    EOI_EXIT_BITMAP0_HIGH           = 0x0000201d,
-    EOI_EXIT_BITMAP1                = 0x0000201e,
-    EOI_EXIT_BITMAP1_HIGH           = 0x0000201f,
-    EOI_EXIT_BITMAP2                = 0x00002020,
-    EOI_EXIT_BITMAP2_HIGH           = 0x00002021,
-    EOI_EXIT_BITMAP3                = 0x00002022,
-    EOI_EXIT_BITMAP3_HIGH           = 0x00002023,
+#define EOI_EXIT_BITMAP(n) (EOI_EXIT_BITMAP0 + (n) * 2) /* n = 0...3 */
     VMREAD_BITMAP                   = 0x00002026,
     VMREAD_BITMAP_HIGH              = 0x00002027,
     VMWRITE_BITMAP                  = 0x00002028,