xref: /linux/arch/um/kernel/skas/process.c (revision 399ead3a6d76cbdd29a716660db5c84a314dab70) 
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4  */
5 
6 #include <linux/init.h>
7 #include <linux/sched/mm.h>
8 #include <linux/sched/task_stack.h>
9 #include <linux/sched/task.h>
10 #include <linux/smp-internal.h>
11 
12 #include <asm/tlbflush.h>
13 
14 #include <as-layout.h>
15 #include <kern.h>
16 #include <os.h>
17 #include <skas.h>
18 #include <kern_util.h>
19 
20 extern void start_kernel(void);
21 
start_kernel_proc(void * unused)22 static int __init start_kernel_proc(void *unused)
23 {
24 	block_signals_trace();
25 
26 	start_kernel();
27 	return 0;
28 }
29 
30 char cpu_irqstacks[NR_CPUS][THREAD_SIZE] __aligned(THREAD_SIZE);
31 
start_uml(void)32 int __init start_uml(void)
33 {
34 	stack_protections((unsigned long) &cpu_irqstacks[0]);
35 	set_sigstack(cpu_irqstacks[0], THREAD_SIZE);
36 
37 	init_new_thread_signals();
38 
39 	init_task.thread.request.thread.proc = start_kernel_proc;
40 	init_task.thread.request.thread.arg = NULL;
41 	return start_idle_thread(task_stack_page(&init_task),
42 				 &init_task.thread.switch_buf);
43 }
44 
current_stub_stack(void)45 unsigned long current_stub_stack(void)
46 {
47 	if (current->mm == NULL)
48 		return 0;
49 
50 	return current->mm->context.id.stack;
51 }
52 
current_mm_id(void)53 struct mm_id *current_mm_id(void)
54 {
55 	if (current->mm == NULL)
56 		return NULL;
57 
58 	return &current->mm->context.id;
59 }
60 
current_mm_sync(void)61 void current_mm_sync(void)
62 {
63 	if (current->mm == NULL)
64 		return;
65 
66 	um_tlb_sync(current->mm);
67 }
68 
69 static DEFINE_SPINLOCK(initial_jmpbuf_spinlock);
70 
initial_jmpbuf_lock(void)71 void initial_jmpbuf_lock(void)
72 {
73 	spin_lock_irq(&initial_jmpbuf_spinlock);
74 }
75 
initial_jmpbuf_unlock(void)76 void initial_jmpbuf_unlock(void)
77 {
78 	spin_unlock_irq(&initial_jmpbuf_spinlock);
79 }
80