um: Add missing headers

This will address below -Wmissing-prototypes warnings:

arch/um/kernel/mem.c:202:8: warning: no previous prototype for ‘pgd_alloc’ [-Wmissing-prototypes]
arch/um/kernel/mem.c:215:7: warning: no previous prototype for ‘uml_kmalloc’ [-Wmissing-prototypes]
arch/um/kernel/process.c:207:6: warning: no previous prototype for ‘arch_cpu_idle’ [-Wmissing-prototypes]
arch/um/kernel/process.c:328:15: warning: no previous prototype for ‘arch_align_stack’ [-Wmissing-prototypes]
arch/um/kernel/reboot.c:45:6: warning: no previous prototype for ‘machine_restart’ [-Wmissing-prototypes]
arch/um/kernel/reboot.c:51:6: warning: no previous prototype for ‘machine_power_off’ [-Wmissing-prototypes]
arch/um/kernel/reboot.c:57:6: warning: no previous prototype for ‘machine_halt’ [-Wmissing-prototypes]
arch/um/kernel/skas/mmu.c:17:5: warning: no previous prototype for ‘init_new_context’ [-Wmissing-prototypes]
arch/um/kernel/skas/mmu.c:60:6: warning: no previous prototype for ‘destroy_context’ [-Wmissing-prototypes]
arch/um/kernel/skas/process.c:36:12: warning: no previous prototype for ‘start_uml’ [-Wmissing-prototypes]
arch/um/kernel/time.c:807:15: warning: no previous prototype for ‘calibrate_delay_is_known’ [-Wmissing-prototypes]
arch/um/kernel/tlb.c:594:6: warning: no previous prototype for ‘force_flush_all’ [-Wmissing-prototypes]
arch/x86/um/bugs_32.c:22:6: warning: no previous prototype for ‘arch_check_bugs’ [-Wmissing-prototypes]
arch/x86/um/bugs_32.c:44:6: warning: no previous prototype for ‘arch_examine_signal’ [-Wmissing-prototypes]
arch/x86/um/bugs_64.c:9:6: warning: no previous prototype for ‘arch_check_bugs’ [-Wmissing-prototypes]
arch/x86/um/bugs_64.c:13:6: warning: no previous prototype for ‘arch_examine_signal’ [-Wmissing-prototypes]
arch/x86/um/elfcore.c:10:12: warning: no previous prototype for ‘elf_core_extra_phdrs’ [-Wmissing-prototypes]
arch/x86/um/elfcore.c:15:5: warning: no previous prototype for ‘elf_core_write_extra_phdrs’ [-Wmissing-prototypes]
arch/x86/um/elfcore.c:42:5: warning: no previous prototype for ‘elf_core_write_extra_data’ [-Wmissing-prototypes]
arch/x86/um/elfcore.c:63:8: warning: no previous prototype for ‘elf_core_extra_data_size’ [-Wmissing-prototypes]
arch/x86/um/fault.c:18:5: warning: no previous prototype for ‘arch_fixup’ [-Wmissing-prototypes]
arch/x86/um/os-Linux/mcontext.c:7:6: warning: no previous prototype for ‘get_regs_from_mc’ [-Wmissing-prototypes]
arch/x86/um/os-Linux/tls.c:22:6: warning: no previous prototype for ‘check_host_supports_tls’ [-Wmissing-prototypes]
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/kernel/mem.c

@@ -12,12 +12,14 @@
 #include <linux/slab.h>
 #include <asm/fixmap.h>
 #include <asm/page.h>
+#include <asm/pgalloc.h>
 #include <as-layout.h>
 #include <init.h>
 #include <kern.h>
 #include <kern_util.h>
 #include <mem_user.h>
 #include <os.h>
+#include <um_malloc.h>
 #include <linux/sched/task.h>
 
 #ifdef CONFIG_KASAN

arch/um/kernel/process.c

@@ -15,6 +15,7 @@
 #include <linux/proc_fs.h>
 #include <linux/ptrace.h>
 #include <linux/random.h>
+#include <linux/cpu.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/sched/debug.h>
@@ -27,6 +28,7 @@
 #include <asm/current.h>
 #include <asm/mmu_context.h>
 #include <asm/switch_to.h>
+#include <asm/exec.h>
 #include <linux/uaccess.h>
 #include <as-layout.h>
 #include <kern_util.h>

arch/um/kernel/reboot.c

@@ -9,6 +9,7 @@
 #include <linux/spinlock.h>
 #include <linux/slab.h>
 #include <linux/oom.h>
+#include <linux/reboot.h>
 #include <kern_util.h>
 #include <os.h>
 #include <skas.h>

arch/um/kernel/skas/mmu.c

@@ -10,6 +10,7 @@
 
 #include <asm/pgalloc.h>
 #include <asm/sections.h>
+#include <asm/mmu_context.h>
 #include <as-layout.h>
 #include <os.h>
 #include <skas.h>

arch/um/kernel/skas/process.c

@@ -12,6 +12,7 @@
 #include <kern.h>
 #include <os.h>
 #include <skas.h>
+#include <kern_util.h>
 
 extern void start_kernel(void);
 

arch/um/kernel/time.c

@@ -19,6 +19,7 @@
 #include <asm/param.h>
 #include <kern_util.h>
 #include <os.h>
+#include <linux/delay.h>
 #include <linux/time-internal.h>
 #include <linux/um_timetravel.h>
 #include <shared/init.h>

arch/um/kernel/tlb.c

@@ -8,6 +8,7 @@
 #include <linux/sched/signal.h>
 
 #include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
 #include <as-layout.h>
 #include <mem_user.h>
 #include <os.h>

arch/x86/um/bugs_32.c

@@ -3,6 +3,7 @@
  * Licensed under the GPL
  */
 
+#include <arch.h>
 #include <signal.h>
 #include <kern_util.h>
 #include <longjmp.h>

arch/x86/um/bugs_64.c

@@ -4,6 +4,7 @@
  * Licensed under the GPL
  */
 
+#include <arch.h>
 #include <sysdep/ptrace.h>
 
 void arch_check_bugs(void)

arch/x86/um/elfcore.c

 // SPDX-License-Identifier: GPL-2.0
 #include <linux/elf.h>
+#include <linux/elfcore.h>
 #include <linux/coredump.h>
 #include <linux/fs.h>
 #include <linux/mm.h>

arch/x86/um/fault.c

@@ -3,6 +3,7 @@
  * Licensed under the GPL
  */
 
+#include <arch.h>
 #include <sysdep/ptrace.h>
 
 /* These two are from asm-um/uaccess.h and linux/module.h, check them. */

arch/x86/um/os-Linux/mcontext.c

@@ -3,6 +3,7 @@
 #define __FRAME_OFFSETS
 #include <asm/ptrace.h>
 #include <sysdep/ptrace.h>
+#include <sysdep/mcontext.h>
 
 void get_regs_from_mc(struct uml_pt_regs *regs, mcontext_t *mc)
 {

arch/x86/um/os-Linux/tls.c

@@ -6,6 +6,7 @@
 #include <sys/syscall.h>
 #include <unistd.h>
 
+#include <os.h>
 #include <sysdep/tls.h>
 
 #ifndef PTRACE_GET_THREAD_AREA