+#ifndef CONFIG_SPARSEMEM
+int pfn_valid(unsigned long pfn)
+{
+ struct meminfo *mi = &meminfo;
+ unsigned int left = 0, right = mi->nr_banks;
+
+ do {
+ unsigned int mid = (right + left) / 2;
+ struct membank *bank = &mi->bank[mid];
+
+ if (pfn < bank_pfn_start(bank))
+ right = mid;
+ else if (pfn >= bank_pfn_end(bank))
+ left = mid + 1;
+ else
+ return 1;
+ } while (left < right);
+ return 0;
+}
+EXPORT_SYMBOL(pfn_valid);
+#endif
+
+static int __init meminfo_cmp(const void *_a, const void *_b)
+{
+ const struct membank *a = _a, *b = _b;
+ long cmp = bank_pfn_start(a) - bank_pfn_start(b);
+ return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
+}
+