v4.19.13 snapshot.
diff --git a/mm/quicklist.c b/mm/quicklist.c
new file mode 100644
index 0000000..5e98ac7
--- /dev/null
+++ b/mm/quicklist.c
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Quicklist support.
+ *
+ * Quicklists are light weight lists of pages that have a defined state
+ * on alloc and free. Pages must be in the quicklist specific defined state
+ * (zero by default) when the page is freed. It seems that the initial idea
+ * for such lists first came from Dave Miller and then various other people
+ * improved on it.
+ *
+ * Copyright (C) 2007 SGI,
+ * Christoph Lameter <cl@linux.com>
+ * Generalized, added support for multiple lists and
+ * constructors / destructors.
+ */
+#include <linux/kernel.h>
+
+#include <linux/gfp.h>
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <linux/quicklist.h>
+
+DEFINE_PER_CPU(struct quicklist [CONFIG_NR_QUICK], quicklist);
+
+#define FRACTION_OF_NODE_MEM 16
+
+static unsigned long max_pages(unsigned long min_pages)
+{
+ unsigned long node_free_pages, max;
+ int node = numa_node_id();
+ struct zone *zones = NODE_DATA(node)->node_zones;
+ int num_cpus_on_node;
+
+ node_free_pages =
+#ifdef CONFIG_ZONE_DMA
+ zone_page_state(&zones[ZONE_DMA], NR_FREE_PAGES) +
+#endif
+#ifdef CONFIG_ZONE_DMA32
+ zone_page_state(&zones[ZONE_DMA32], NR_FREE_PAGES) +
+#endif
+ zone_page_state(&zones[ZONE_NORMAL], NR_FREE_PAGES);
+
+ max = node_free_pages / FRACTION_OF_NODE_MEM;
+
+ num_cpus_on_node = cpumask_weight(cpumask_of_node(node));
+ max /= num_cpus_on_node;
+
+ return max(max, min_pages);
+}
+
+static long min_pages_to_free(struct quicklist *q,
+ unsigned long min_pages, long max_free)
+{
+ long pages_to_free;
+
+ pages_to_free = q->nr_pages - max_pages(min_pages);
+
+ return min(pages_to_free, max_free);
+}
+
+/*
+ * Trim down the number of pages in the quicklist
+ */
+void quicklist_trim(int nr, void (*dtor)(void *),
+ unsigned long min_pages, unsigned long max_free)
+{
+ long pages_to_free;
+ struct quicklist *q;
+
+ q = &get_cpu_var(quicklist)[nr];
+ if (q->nr_pages > min_pages) {
+ pages_to_free = min_pages_to_free(q, min_pages, max_free);
+
+ while (pages_to_free > 0) {
+ /*
+ * We pass a gfp_t of 0 to quicklist_alloc here
+ * because we will never call into the page allocator.
+ */
+ void *p = quicklist_alloc(nr, 0, NULL);
+
+ if (dtor)
+ dtor(p);
+ free_page((unsigned long)p);
+ pages_to_free--;
+ }
+ }
+ put_cpu_var(quicklist);
+}
+
+unsigned long quicklist_total_size(void)
+{
+ unsigned long count = 0;
+ int cpu;
+ struct quicklist *ql, *q;
+
+ for_each_online_cpu(cpu) {
+ ql = per_cpu(quicklist, cpu);
+ for (q = ql; q < ql + CONFIG_NR_QUICK; q++)
+ count += q->nr_pages;
+ }
+ return count;
+}
+