1/*
 2 * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 3 * Copyright 2003 PathScale, Inc.
 4 *
 5 * Licensed under the GPL
 6 */
 7
 8#include <linux/sched.h>
 9#include <linux/sched/mm.h>
10#include <linux/syscalls.h>
11#include <linux/uaccess.h>
12#include <asm/prctl.h> /* XXX This should get the constants from libc */
 
13#include <os.h>
14
15long arch_prctl(struct task_struct *task, int option,
16		unsigned long __user *arg2)
17{
18	unsigned long *ptr = arg2, tmp;
19	long ret;
20	int pid = task->mm->context.id.u.pid;
21
22	/*
23	 * With ARCH_SET_FS (and ARCH_SET_GS is treated similarly to
24	 * be safe), we need to call arch_prctl on the host because
25	 * setting %fs may result in something else happening (like a
26	 * GDT or thread.fs being set instead).  So, we let the host
27	 * fiddle the registers and thread struct and restore the
28	 * registers afterwards.
29	 *
30	 * So, the saved registers are stored to the process (this
31	 * needed because a stub may have been the last thing to run),
32	 * arch_prctl is run on the host, then the registers are read
33	 * back.
34	 */
35	switch (option) {
36	case ARCH_SET_FS:
37	case ARCH_SET_GS:
38		ret = restore_registers(pid, &current->thread.regs.regs);
39		if (ret)
40			return ret;
41		break;
42	case ARCH_GET_FS:
43	case ARCH_GET_GS:
44		/*
45		 * With these two, we read to a local pointer and
46		 * put_user it to the userspace pointer that we were
47		 * given.  If addr isn't valid (because it hasn't been
48		 * faulted in or is just bogus), we want put_user to
49		 * fault it in (or return -EFAULT) instead of having
50		 * the host return -EFAULT.
51		 */
52		ptr = &tmp;
53	}
54
55	ret = os_arch_prctl(pid, option, ptr);
56	if (ret)
57		return ret;
58
59	switch (option) {
60	case ARCH_SET_FS:
61		current->thread.arch.fs = (unsigned long) ptr;
62		ret = save_registers(pid, &current->thread.regs.regs);
63		break;
64	case ARCH_SET_GS:
65		ret = save_registers(pid, &current->thread.regs.regs);
66		break;
67	case ARCH_GET_FS:
68		ret = put_user(tmp, arg2);
69		break;
70	case ARCH_GET_GS:
71		ret = put_user(tmp, arg2);
72		break;
73	}
74
75	return ret;
76}
77
78SYSCALL_DEFINE2(arch_prctl, int, option, unsigned long, arg2)
79{
80	return arch_prctl(current, option, (unsigned long __user *) arg2);
81}
82
83void arch_switch_to(struct task_struct *to)
84{
85	if ((to->thread.arch.fs == 0) || (to->mm == NULL))
86		return;
87
88	arch_prctl(to, ARCH_SET_FS, (void __user *) to->thread.arch.fs);
 
 
 
 
 
 
 
 
 
 
89}

  1/*
  2 * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  3 * Copyright 2003 PathScale, Inc.
  4 *
  5 * Licensed under the GPL
  6 */
  7
  8#include <linux/sched.h>
  9#include <linux/sched/mm.h>
 10#include <linux/syscalls.h>
 11#include <linux/uaccess.h>
 12#include <asm/prctl.h> /* XXX This should get the constants from libc */
 13#include <registers.h>
 14#include <os.h>
 15
 16long arch_prctl(struct task_struct *task, int option,
 17		unsigned long __user *arg2)
 18{
 19	unsigned long *ptr = arg2, tmp;
 20	long ret;
 21	int pid = task->mm->context.id.u.pid;
 22
 23	/*
 24	 * With ARCH_SET_FS (and ARCH_SET_GS is treated similarly to
 25	 * be safe), we need to call arch_prctl on the host because
 26	 * setting %fs may result in something else happening (like a
 27	 * GDT or thread.fs being set instead).  So, we let the host
 28	 * fiddle the registers and thread struct and restore the
 29	 * registers afterwards.
 30	 *
 31	 * So, the saved registers are stored to the process (this
 32	 * needed because a stub may have been the last thing to run),
 33	 * arch_prctl is run on the host, then the registers are read
 34	 * back.
 35	 */
 36	switch (option) {
 37	case ARCH_SET_FS:
 38	case ARCH_SET_GS:
 39		ret = restore_pid_registers(pid, &current->thread.regs.regs);
 40		if (ret)
 41			return ret;
 42		break;
 43	case ARCH_GET_FS:
 44	case ARCH_GET_GS:
 45		/*
 46		 * With these two, we read to a local pointer and
 47		 * put_user it to the userspace pointer that we were
 48		 * given.  If addr isn't valid (because it hasn't been
 49		 * faulted in or is just bogus), we want put_user to
 50		 * fault it in (or return -EFAULT) instead of having
 51		 * the host return -EFAULT.
 52		 */
 53		ptr = &tmp;
 54	}
 55
 56	ret = os_arch_prctl(pid, option, ptr);
 57	if (ret)
 58		return ret;
 59
 60	switch (option) {
 61	case ARCH_SET_FS:
 62		current->thread.arch.fs = (unsigned long) ptr;
 63		ret = save_registers(pid, &current->thread.regs.regs);
 64		break;
 65	case ARCH_SET_GS:
 66		ret = save_registers(pid, &current->thread.regs.regs);
 67		break;
 68	case ARCH_GET_FS:
 69		ret = put_user(tmp, arg2);
 70		break;
 71	case ARCH_GET_GS:
 72		ret = put_user(tmp, arg2);
 73		break;
 74	}
 75
 76	return ret;
 77}
 78
 79SYSCALL_DEFINE2(arch_prctl, int, option, unsigned long, arg2)
 80{
 81	return arch_prctl(current, option, (unsigned long __user *) arg2);
 82}
 83
 84void arch_switch_to(struct task_struct *to)
 85{
 86	if ((to->thread.arch.fs == 0) || (to->mm == NULL))
 87		return;
 88
 89	arch_prctl(to, ARCH_SET_FS, (void __user *) to->thread.arch.fs);
 90}
 91
 92SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
 93		unsigned long, prot, unsigned long, flags,
 94		unsigned long, fd, unsigned long, off)
 95{
 96	if (off & ~PAGE_MASK)
 97		return -EINVAL;
 98
 99	return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
100}