[RFC PATCH V5 11/15] evtchn: use pointers to reference evtchn_pending/mask

[Wei Liu <wei.liu2@citrix.com>]

This allows better code sharing between 2/3-level event channel ABIs.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
---
 xen/arch/arm/domain.c          |    1 +
 xen/arch/x86/domain.c          |    1 +
 xen/common/event_channel.c     |    6 ++++++
 xen/common/evtchn_bitmap_abi.c |   14 +++++++-------
 xen/include/xen/event.h        |    3 +++
 xen/include/xen/sched.h        |    2 ++
 6 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index bca3d89..f6a5560 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -471,6 +471,7 @@ int arch_domain_create(struct domain *d, unsigned int domcr_flags)
     d->arch.vmpidr = boot_cpu_data.mpidr.bits;
 
     clear_page(d->shared_info);
+    evtchn_set_default_bitmap(d);
     share_xen_page_with_guest(
         virt_to_page(d->shared_info), d, XENSHARE_writable);
 
diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 8d30d08..d7912b3 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -547,6 +547,7 @@ int arch_domain_create(struct domain *d, unsigned int domcr_flags)
             goto fail;
 
         clear_page(d->shared_info);
+        evtchn_set_default_bitmap(d);
         share_xen_page_with_guest(
             virt_to_page(d->shared_info), d, XENSHARE_writable);
 
diff --git a/xen/common/event_channel.c b/xen/common/event_channel.c
index 4d02fc7..152b77a 100644
--- a/xen/common/event_channel.c
+++ b/xen/common/event_channel.c
@@ -1177,6 +1177,12 @@ void evtchn_set_abi(struct domain *d, uint64_t abi)
     }
 }
 
+void evtchn_set_default_bitmap(struct domain *d)
+{
+    d->evtchn_pending = (xen_ulong_t *)shared_info(d, evtchn_pending);
+    d->evtchn_mask = (xen_ulong_t *)shared_info(d, evtchn_mask);
+}
+
 int evtchn_init(struct domain *d)
 {
     spin_lock_init(&d->event_lock);
diff --git a/xen/common/evtchn_bitmap_abi.c b/xen/common/evtchn_bitmap_abi.c
index 0d747bc..180a4bc 100644
--- a/xen/common/evtchn_bitmap_abi.c
+++ b/xen/common/evtchn_bitmap_abi.c
@@ -24,12 +24,12 @@
 
 int evtchn_bitmap_is_pending(struct domain *d, int port)
 {
-    return test_bit(port, &shared_info(d, evtchn_pending));
+    return test_bit(port, d->evtchn_pending);
 }
 
 int evtchn_bitmap_is_masked(struct domain *d, int port)
 {
-    return test_bit(port, &shared_info(d, evtchn_mask));
+    return test_bit(port, d->evtchn_mask);
 }
 
 void evtchn_bitmap_set_pending(struct vcpu *v, int port)
@@ -44,10 +44,10 @@ void evtchn_bitmap_set_pending(struct vcpu *v, int port)
      * others may require explicit memory barriers.
      */
 
-    if ( test_and_set_bit(port, &shared_info(d, evtchn_pending)) )
+    if ( test_and_set_bit(port, d->evtchn_pending) )
         return;
 
-    if ( !test_bit        (port, &shared_info(d, evtchn_mask)) &&
+    if ( !test_bit        (port, d->evtchn_mask) &&
          !test_and_set_bit(port / BITS_PER_EVTCHN_WORD(d),
                            &vcpu_info(v, evtchn_pending_sel)) )
     {
@@ -75,7 +75,7 @@ void evtchn_bitmap_set_pending(struct vcpu *v, int port)
 
 void evtchn_bitmap_clear_pending(struct domain *d, int port)
 {
-    clear_bit(port, &shared_info(d, evtchn_pending));
+    clear_bit(port, d->evtchn_pending);
 }
 
 int evtchn_bitmap_unmask(unsigned int port)
@@ -94,8 +94,8 @@ int evtchn_bitmap_unmask(unsigned int port)
      * These operations must happen in strict order. Based on
      * include/xen/event.h:evtchn_set_pending().
      */
-    if ( test_and_clear_bit(port, &shared_info(d, evtchn_mask)) &&
-         test_bit          (port, &shared_info(d, evtchn_pending)) &&
+    if ( test_and_clear_bit(port, d->evtchn_mask) &&
+         test_bit          (port, d->evtchn_pending) &&
          !test_and_set_bit (port / BITS_PER_EVTCHN_WORD(d),
                             &vcpu_info(v, evtchn_pending_sel)) )
     {
diff --git a/xen/include/xen/event.h b/xen/include/xen/event.h
index 9531029..2387461 100644
--- a/xen/include/xen/event.h
+++ b/xen/include/xen/event.h
@@ -135,6 +135,9 @@ void notify_via_xen_event_channel(struct domain *ld, int lport);
         mb(); /* set blocked status /then/ caller does his work */      \
     } while ( 0 )
 
+/* This is called after domain's shared info page is setup */
+void evtchn_set_default_bitmap(struct domain *d);
+
 /* 2-level ABI routines */
 int evtchn_bitmap_is_pending(struct domain *d, int port);
 int evtchn_bitmap_is_masked(struct domain *d, int port);
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index 6bf96bd..71eebb6 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -270,6 +270,8 @@ struct domain
     struct evtchn  **evtchn[NR_EVTCHN_GROUPS];
     const struct evtchn_port_ops *evtchn_ops;
     spinlock_t       event_lock;
+    xen_ulong_t     *evtchn_pending;
+    xen_ulong_t     *evtchn_mask;
     unsigned int     max_evtchns;
     unsigned int     evtchn_extended;
 
-- 
1.7.10.4