1 files changed, 26 insertions, 0 deletions

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 1d6b29e4e2c3..19b6129eab23 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -12,6 +12,8 @@
 #include <linux/bpf.h>
 #include <linux/syscalls.h>
 #include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mmzone.h>
 #include <linux/anon_inodes.h>
 #include <linux/file.h>
 #include <linux/license.h>
@@ -49,6 +51,30 @@ void bpf_register_map_type(struct bpf_map_type_list *tl)
         list_add(&tl->list_node, &bpf_map_types);
 }
 
+void *bpf_map_area_alloc(size_t size)
+{
+        /* We definitely need __GFP_NORETRY, so OOM killer doesn't
+         * trigger under memory pressure as we really just want to
+         * fail instead.
+         */
+        const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO;
+        void *area;
+
+        if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
+                area = kmalloc(size, GFP_USER | flags);
+                if (area != NULL)
+                        return area;
+        }
+
+        return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | flags,
+                         PAGE_KERNEL);
+}
+
+void bpf_map_area_free(void *area)
+{
+        kvfree(area);
+}
+
 int bpf_map_precharge_memlock(u32 pages)
 {
         struct user_struct *user = get_current_user();