[PATCH v3 15/15] tools/tests: Enable xen-access on ARM

[Tamas K Lengyel <tklengyel@sec.in.tum.de>]

On ARM the guest memory doesn't start from 0, thus we include the
required headers and define GUEST_RAM_BASE_PFN in both architecture
to be passed to mem_access as the starting pfn.
We also define the ARM specific test_and_set_bit function.

Signed-off-by: Tamas K Lengyel <tklengyel@sec.in.tum.de>
---
 tools/tests/xen-access/Makefile     |  4 +--
 tools/tests/xen-access/xen-access.c | 53 +++++++++++++++++++++++++++++--------
 2 files changed, 43 insertions(+), 14 deletions(-)

diff --git a/tools/tests/xen-access/Makefile b/tools/tests/xen-access/Makefile
index 65eef99..698355c 100644
--- a/tools/tests/xen-access/Makefile
+++ b/tools/tests/xen-access/Makefile
@@ -7,9 +7,7 @@ CFLAGS += $(CFLAGS_libxenctrl)
 CFLAGS += $(CFLAGS_libxenguest)
 CFLAGS += $(CFLAGS_xeninclude)
 
-TARGETS-y := 
-TARGETS-$(CONFIG_X86) += xen-access
-TARGETS := $(TARGETS-y)
+TARGETS := xen-access
 
 .PHONY: all
 all: build
diff --git a/tools/tests/xen-access/xen-access.c b/tools/tests/xen-access/xen-access.c
index 090df5f..187c72f 100644
--- a/tools/tests/xen-access/xen-access.c
+++ b/tools/tests/xen-access/xen-access.c
@@ -41,22 +41,16 @@
 #include <xenctrl.h>
 #include <xen/mem_event.h>
 
-#define DPRINTF(a, b...) fprintf(stderr, a, ## b)
-#define ERROR(a, b...) fprintf(stderr, a "\n", ## b)
-#define PERROR(a, b...) fprintf(stderr, a ": %s\n", ## b, strerror(errno))
-
-/* Spinlock and mem event definitions */
-
-#define SPIN_LOCK_UNLOCKED 0
+#ifdef CONFIG_X86
 
+#define GUEST_RAM_BASE_PFN 0ULL
 #define ADDR (*(volatile long *) addr)
+
 /**
  * test_and_set_bit - Set a bit and return its old value
  * @nr: Bit to set
  * @addr: Address to count from
  *
- * This operation is atomic and cannot be reordered.
- * It also implies a memory barrier.
  */
 static inline int test_and_set_bit(int nr, volatile void *addr)
 {
@@ -69,6 +63,43 @@ static inline int test_and_set_bit(int nr, volatile void *addr)
     return oldbit;
 }
 
+#else /* CONFIG_X86 */
+
+#include <xen/arch-arm.h>
+
+#define PAGE_SHIFT              12
+#define GUEST_RAM_BASE_PFN      GUEST_RAM_BASE >> PAGE_SHIFT
+#define BITS_PER_WORD           32
+#define BIT_MASK(nr)            (1UL << ((nr) % BITS_PER_WORD))
+#define BIT_WORD(nr)            ((nr) / BITS_PER_WORD)
+
+/**
+ * test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ */
+static inline int test_and_set_bit(int nr, volatile void *addr)
+{
+        unsigned int mask = BIT_MASK(nr);
+        volatile unsigned int *p =
+                ((volatile unsigned int *)addr) + BIT_WORD(nr);
+        unsigned int old = *p;
+
+        *p = old | mask;
+        return (old & mask) != 0;
+}
+
+#endif
+
+#define DPRINTF(a, b...) fprintf(stderr, a, ## b)
+#define ERROR(a, b...) fprintf(stderr, a "\n", ## b)
+#define PERROR(a, b...) fprintf(stderr, a ": %s\n", ## b, strerror(errno))
+
+/* Spinlock and mem event definitions */
+
+#define SPIN_LOCK_UNLOCKED 0
+
 typedef int spinlock_t;
 
 static inline void spin_lock(spinlock_t *lock)
@@ -492,7 +523,7 @@ int main(int argc, char *argv[])
         goto exit;
     }
 
-    rc = xc_set_mem_access(xch, domain_id, default_access, 0,
+    rc = xc_set_mem_access(xch, domain_id, default_access, GUEST_RAM_BASE_PFN,
                            xenaccess->domain_info->max_pages);
     if ( rc < 0 )
     {
@@ -520,7 +551,7 @@ int main(int argc, char *argv[])
 
             /* Unregister for every event */
             rc = xc_set_mem_access(xch, domain_id, XENMEM_access_rwx, ~0ull, 0);
-            rc = xc_set_mem_access(xch, domain_id, XENMEM_access_rwx, 0,
+            rc = xc_set_mem_access(xch, domain_id, XENMEM_access_rwx, GUEST_RAM_BASE_PFN,
                                    xenaccess->domain_info->max_pages);
             rc = xc_hvm_param_set(xch, domain_id, HVM_PARAM_MEMORY_EVENT_INT3, HVMPME_mode_disabled);
 
-- 
2.1.0.rc1