android_kernel_xiaomi_sm8350/arch/um/sys-i386/syscalls.c
Paolo 'Blaisorblade' Giarrusso aa6758d486 [PATCH] uml: implement {get,set}_thread_area for i386
Implement sys_[gs]et_thread_area and the corresponding ptrace operations for
UML.  This is the main chunk, additional parts follow.  This implementation is
now well tested and has run reliably for some time, and we've understood all
the previously existing problems.

Their implementation saves the new GDT content and then forwards the call to
the host when appropriate, i.e.  immediately when the target process is
running or on context switch otherwise (i.e.  on fork and on ptrace() calls).

In SKAS mode, we must switch registers on each context switch (because SKAS
does not switches tls_array together with current->mm).

Also, added get_cpu() locking; this has been done for SKAS mode, since TT does
not need it (it does not use smp_processor_id()).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:52 -08:00

202 lines
4.9 KiB
C

/*
* Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
* Licensed under the GPL
*/
#include "linux/sched.h"
#include "linux/shm.h"
#include "asm/ipc.h"
#include "asm/mman.h"
#include "asm/uaccess.h"
#include "asm/unistd.h"
/*
* Perform the select(nd, in, out, ex, tv) and mmap() system
* calls. Linux/i386 didn't use to be able to handle more than
* 4 system call parameters, so these system calls used a memory
* block for parameter passing..
*/
struct mmap_arg_struct {
unsigned long addr;
unsigned long len;
unsigned long prot;
unsigned long flags;
unsigned long fd;
unsigned long offset;
};
extern int old_mmap(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long offset);
long old_mmap_i386(struct mmap_arg_struct __user *arg)
{
struct mmap_arg_struct a;
int err = -EFAULT;
if (copy_from_user(&a, arg, sizeof(a)))
goto out;
err = old_mmap(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
out:
return err;
}
struct sel_arg_struct {
unsigned long n;
fd_set __user *inp;
fd_set __user *outp;
fd_set __user *exp;
struct timeval __user *tvp;
};
long old_select(struct sel_arg_struct __user *arg)
{
struct sel_arg_struct a;
if (copy_from_user(&a, arg, sizeof(a)))
return -EFAULT;
/* sys_select() does the appropriate kernel locking */
return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
}
/*
* The prototype on i386 is:
*
* int clone(int flags, void * child_stack, int * parent_tidptr, struct user_desc * newtls, int * child_tidptr)
*
* and the "newtls" arg. on i386 is read by copy_thread directly from the
* register saved on the stack.
*/
long sys_clone(unsigned long clone_flags, unsigned long newsp,
int __user *parent_tid, void *newtls, int __user *child_tid)
{
long ret;
if (!newsp)
newsp = UPT_SP(&current->thread.regs.regs);
current->thread.forking = 1;
ret = do_fork(clone_flags, newsp, &current->thread.regs, 0, parent_tid,
child_tid);
current->thread.forking = 0;
return ret;
}
/*
* sys_ipc() is the de-multiplexer for the SysV IPC calls..
*
* This is really horribly ugly.
*/
long sys_ipc (uint call, int first, int second,
int third, void __user *ptr, long fifth)
{
int version, ret;
version = call >> 16; /* hack for backward compatibility */
call &= 0xffff;
switch (call) {
case SEMOP:
return sys_semtimedop(first, (struct sembuf *) ptr, second,
NULL);
case SEMTIMEDOP:
return sys_semtimedop(first, (struct sembuf *) ptr, second,
(const struct timespec *) fifth);
case SEMGET:
return sys_semget (first, second, third);
case SEMCTL: {
union semun fourth;
if (!ptr)
return -EINVAL;
if (get_user(fourth.__pad, (void __user * __user *) ptr))
return -EFAULT;
return sys_semctl (first, second, third, fourth);
}
case MSGSND:
return sys_msgsnd (first, (struct msgbuf *) ptr,
second, third);
case MSGRCV:
switch (version) {
case 0: {
struct ipc_kludge tmp;
if (!ptr)
return -EINVAL;
if (copy_from_user(&tmp,
(struct ipc_kludge *) ptr,
sizeof (tmp)))
return -EFAULT;
return sys_msgrcv (first, tmp.msgp, second,
tmp.msgtyp, third);
}
default:
panic("msgrcv with version != 0");
return sys_msgrcv (first,
(struct msgbuf *) ptr,
second, fifth, third);
}
case MSGGET:
return sys_msgget ((key_t) first, second);
case MSGCTL:
return sys_msgctl (first, second, (struct msqid_ds *) ptr);
case SHMAT:
switch (version) {
default: {
ulong raddr;
ret = do_shmat (first, (char *) ptr, second, &raddr);
if (ret)
return ret;
return put_user (raddr, (ulong *) third);
}
case 1: /* iBCS2 emulator entry point */
if (!segment_eq(get_fs(), get_ds()))
return -EINVAL;
return do_shmat (first, (char *) ptr, second, (ulong *) third);
}
case SHMDT:
return sys_shmdt ((char *)ptr);
case SHMGET:
return sys_shmget (first, second, third);
case SHMCTL:
return sys_shmctl (first, second,
(struct shmid_ds *) ptr);
default:
return -ENOSYS;
}
}
long sys_sigaction(int sig, const struct old_sigaction __user *act,
struct old_sigaction __user *oact)
{
struct k_sigaction new_ka, old_ka;
int ret;
if (act) {
old_sigset_t mask;
if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
__get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
__get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
return -EFAULT;
__get_user(new_ka.sa.sa_flags, &act->sa_flags);
__get_user(mask, &act->sa_mask);
siginitset(&new_ka.sa.sa_mask, mask);
}
ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
if (!ret && oact) {
if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
__put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
__put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
return -EFAULT;
__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
}
return ret;
}