ARM: Fix ptrace accesses

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 43 insertions, 8 deletions

diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index 6f3a4b7a3b82..e34f095e2090 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -13,6 +13,7 @@
 
 #include <asm/cacheflush.h>
 #include <asm/cachetype.h>
+#include <asm/smp_plat.h>
 #include <asm/system.h>
 #include <asm/tlbflush.h>
 
@@ -87,13 +88,26 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsig
         if (vma->vm_flags & VM_EXEC && icache_is_vivt_asid_tagged())
                 __flush_icache_all();
 }
+#else
+#define flush_pfn_alias(pfn,vaddr)      do { } while (0)
+#endif
 
+#ifdef CONFIG_SMP
+static void flush_ptrace_access_other(void *args)
+{
+        __flush_icache_all();
+}
+#endif
+
+static
 void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
-                         unsigned long uaddr, void *kaddr,
-                         unsigned long len, int write)
+                         unsigned long uaddr, void *kaddr, unsigned long len)
 {
         if (cache_is_vivt()) {
-                vivt_flush_ptrace_access(vma, page, uaddr, kaddr, len, write);
+                if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(vma->vm_mm))) {
+                        unsigned long addr = (unsigned long)kaddr;
+                        __cpuc_coherent_kern_range(addr, addr + len);
+                }
                 return;
         }
 
@@ -104,16 +118,37 @@ void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
         }
 
         /* VIPT non-aliasing cache */
-        if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(vma->vm_mm)) &&
-            vma->vm_flags & VM_EXEC) {
+        if (vma->vm_flags & VM_EXEC) {
                 unsigned long addr = (unsigned long)kaddr;
-                /* only flushing the kernel mapping on non-aliasing VIPT */
                 __cpuc_coherent_kern_range(addr, addr + len);
+#ifdef CONFIG_SMP
+                if (cache_ops_need_broadcast())
+                        smp_call_function(flush_ptrace_access_other,
+                                          NULL, 1);
+#endif
         }
 }
-#else
-#define flush_pfn_alias(pfn,vaddr)      do { } while (0)
+
+/*
+ * Copy user data from/to a page which is mapped into a different
+ * processes address space.  Really, we want to allow our "user
+ * space" model to handle this.
+ *
+ * Note that this code needs to run on the current CPU.
+ */
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+                       unsigned long uaddr, void *dst, const void *src,
+                       unsigned long len)
+{
+#ifdef CONFIG_SMP
+        preempt_disable();
 #endif
+        memcpy(dst, src, len);
+        flush_ptrace_access(vma, page, uaddr, dst, len);
+#ifdef CONFIG_SMP
+        preempt_enable();
+#endif
+}
 
 void __flush_dcache_page(struct address_space *mapping, struct page *page)
 {