+static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
+{
+ unsigned long pfn;
+
+ /* Turn a kernel-virtual address into a physical page frame */
+ pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
+
+ /*
+ * RED-PEN: on some architectures there is more mapped memory
+ * than available in mem_map which pfn_valid checks
+ * for. Perhaps should add a new macro here.
+ *
+ * RED-PEN: vmalloc is not supported right now.
+ */
+ if (!pfn_valid(pfn))
+ return -EIO;
+
+ vma->vm_pgoff = pfn;
+ return mmap_mem(file, vma);
+}
+
+#ifdef CONFIG_CRASH_DUMP
+/*
+ * Read memory corresponding to the old kernel.
+ */
+static ssize_t read_oldmem(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ unsigned long pfn, offset;
+ size_t read = 0, csize;
+ int rc = 0;
+
+ while (count) {
+ pfn = *ppos / PAGE_SIZE;
+ if (pfn > saved_max_pfn)
+ return read;
+
+ offset = (unsigned long)(*ppos % PAGE_SIZE);
+ if (count > PAGE_SIZE - offset)
+ csize = PAGE_SIZE - offset;
+ else
+ csize = count;
+
+ rc = copy_oldmem_page(pfn, buf, csize, offset, 1);
+ if (rc < 0)
+ return rc;
+ buf += csize;
+ *ppos += csize;
+ read += csize;
+ count -= csize;
+ }
+ return read;
+}
+#endif
+