1 files changed, 20 insertions, 22 deletions

diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index c84f33d51f7b..7dd21720e5b0 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -40,28 +40,26 @@ static inline void *load_real_addr(void *addr)
 }
 
 /*
- * Copy up to one page to vmalloc or real memory
+ * Copy real to virtual or real memory
  */
-static ssize_t copy_page_real(void *buf, void *src, size_t csize)
+static int copy_from_realmem(void *dest, void *src, size_t count)
 {
-        size_t size;
+        unsigned long size;
+        int rc;
 
-        if (is_vmalloc_addr(buf)) {
-                BUG_ON(csize >= PAGE_SIZE);
-                /* If buf is not page aligned, copy first part */
-                size = min(roundup(__pa(buf), PAGE_SIZE) - __pa(buf), csize);
-                if (size) {
-                        if (memcpy_real(load_real_addr(buf), src, size))
-                                return -EFAULT;
-                        buf += size;
-                        src += size;
-                }
-                /* Copy second part */
-                size = csize - size;
-                return (size) ? memcpy_real(load_real_addr(buf), src, size) : 0;
-        } else {
-                return memcpy_real(buf, src, csize);
-        }
+        if (!count)
+                return 0;
+        if (!is_vmalloc_or_module_addr(dest))
+                return memcpy_real(dest, src, count);
+        do {
+                size = min(count, PAGE_SIZE - (__pa(dest) & ~PAGE_MASK));
+                if (memcpy_real(load_real_addr(dest), src, size))
+                        return -EFAULT;
+                count -= size;
+                dest += size;
+                src += size;
+        } while (count);
+        return 0;
 }
 
 /*
@@ -114,7 +112,7 @@ static ssize_t copy_oldmem_page_kdump(char *buf, size_t csize,
                 rc = copy_to_user_real((void __force __user *) buf,
                                        (void *) src, csize);
         else
-                rc = copy_page_real(buf, (void *) src, csize);
+                rc = copy_from_realmem(buf, (void *) src, csize);
         return (rc == 0) ? rc : csize;
 }
 
@@ -210,7 +208,7 @@ int copy_from_oldmem(void *dest, void *src, size_t count)
         if (OLDMEM_BASE) {
                 if ((unsigned long) src < OLDMEM_SIZE) {
                         copied = min(count, OLDMEM_SIZE - (unsigned long) src);
-                        rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
+                        rc = copy_from_realmem(dest, src + OLDMEM_BASE, copied);
                         if (rc)
                                 return rc;
                 }
@@ -223,7 +221,7 @@ int copy_from_oldmem(void *dest, void *src, size_t count)
                                 return rc;
                 }
         }
-        return memcpy_real(dest + copied, src + copied, count - copied);
+        return copy_from_realmem(dest + copied, src + copied, count - copied);
 }
 
 /*