Add fallocate/fallocate64/posix_fallocate/posix_fallocate64.

Bug: 5287571
Bug: 12612860
Change-Id: I4501b9c6cdf9a830336ce0b3afc4ea716b6a0f6f
diff --git a/libc/arch-x86_64/syscalls/fallocate.S b/libc/arch-x86_64/syscalls/fallocate.S
new file mode 100644
index 0000000..e6959ca
--- /dev/null
+++ b/libc/arch-x86_64/syscalls/fallocate.S
@@ -0,0 +1,20 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <private/bionic_asm.h>
+
+ENTRY(fallocate)
+    movq    %rcx, %r10
+    movl    $__NR_fallocate, %eax
+    syscall
+    cmpq    $-MAX_ERRNO, %rax
+    jb      1f
+    negl    %eax
+    movl    %eax, %edi
+    call    __set_errno
+    orq     $-1, %rax
+1:
+    ret
+END(fallocate)
+
+    .globl _C_LABEL(fallocate64)
+    .equ _C_LABEL(fallocate64), _C_LABEL(fallocate)