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/*
* MIPS specific syscall handling functions and syscalls
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1995 by Ralf Baechle
*/
#include <linux/linkage.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/sched.h>
#include <linux/unistd.h>
#include <asm/ptrace.h>
#include <asm/segment.h>
#include <asm/signal.h>
extern asmlinkage void syscall_trace(void);
typedef asmlinkage int (*syscall_t)(void *a0,...);
extern asmlinkage int do_syscalls(struct pt_regs *regs, syscall_t fun,
int narg);
extern syscall_t sys_call_table[];
extern unsigned char sys_narg_table[];
asmlinkage int sys_pipe(struct pt_regs *regs)
{
int fd[2];
int error;
error = do_pipe(fd);
if (error)
return error;
regs->reg2 = fd[0];
regs->reg3 = fd[1];
return 0;
}
asmlinkage unsigned long sys_mmap(unsigned long addr, size_t len, int prot,
int flags, int fd, off_t offset)
{
struct file * file = NULL;
if (flags & MAP_RENAME) {
if (fd >= NR_OPEN || !(file = current->files->fd[fd]))
return -EBADF;
}
flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
return do_mmap(file, addr, len, prot, flags, offset);
}
asmlinkage int sys_idle(void)
{
if (current->pid != 0)
return -EPERM;
/* endless idle loop with no priority at all */
current->counter = -100;
for (;;) {
/*
* R4[26]00 have wait, R4[04]00 don't.
*/
if (wait_available && !need_resched)
__asm__(".set\tmips3\n\t"
"wait\n\t"
".set\tmips0\n\t");
schedule();
}
}
asmlinkage int sys_fork(struct pt_regs *regs)
{
return do_fork(SIGCHLD, regs->reg29, regs);
}
asmlinkage int sys_clone(struct pt_regs *regs)
{
unsigned long clone_flags;
unsigned long newsp;
clone_flags = regs->reg4;
newsp = regs->reg5;
if (!newsp)
newsp = regs->reg29;
return do_fork(clone_flags, newsp, regs);
}
/*
* sys_execve() executes a new program.
*/
asmlinkage int sys_execve(struct pt_regs *regs)
{
int error;
char * filename;
error = getname((char *) regs->reg4, &filename);
if (error)
return error;
error = do_execve(filename, (char **) regs->reg5,
(char **) regs->reg6, regs);
putname(filename);
return error;
}
/*
* Do the indirect syscall syscall.
*/
asmlinkage int sys_syscall(unsigned long a0, unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4, unsigned long a5,
unsigned long a6)
{
syscall_t syscall;
if (a0 > __NR_Linux + __NR_Linux_syscalls)
return -ENOSYS;
syscall = sys_call_table[a0];
/*
* Prevent stack overflow by recursive
* syscall(__NR_syscall, __NR_syscall,...);
*/
if (syscall == (syscall_t) sys_syscall)
return -EINVAL;
if (syscall == NULL)
return -ENOSYS;
return syscall((void *)a0, a1, a2, a3, a4, a5, a6);
}
void do_sys(struct pt_regs *regs)
{
unsigned long syscallnr, usp;
syscall_t syscall;
int errno, narg;
/*
* Compute the return address;
*/
if (regs->cp0_cause & CAUSEF_BD)
{
/*
* This syscall is in a branch delay slot. Since we don't do
* branch delay slot handling we would get a process trying
* to do syscalls ever and ever again. So better zap it.
*/
printk("%s: syscall in branch delay slot.\n", current->comm);
current->sig->action[SIGILL-1].sa_handler = NULL;
current->blocked &= ~(1<<(SIGILL-1));
send_sig(SIGILL, current, 1);
return;
}
regs->cp0_epc += 4;
syscallnr = regs->reg2;
if (syscallnr > (__NR_Linux + __NR_Linux_syscalls))
goto illegal_syscall;
syscall = sys_call_table[syscallnr];
if (syscall == NULL)
goto illegal_syscall;
narg = sys_narg_table[syscallnr];
if (narg > 4)
{
/*
* Verify that we can safely get the additional parameters
* from the user stack. Of course I could read the params
* from unaligned addresses ... Consider this a programming
* course caliber .45.
*/
usp = regs->reg29;
if (usp & 3)
{
printk("unaligned usp\n");
send_sig(SIGSEGV, current, 1);
regs->reg2 = EFAULT;
regs->reg7 = 1;
return;
}
errno = verify_area(VERIFY_READ, (void *) (usp + 16),
(narg - 4) * sizeof(unsigned long));
if (errno < 0)
goto bad_syscall;
}
if ((current->flags & PF_TRACESYS) == 0)
{
errno = do_syscalls(regs, syscall, narg);
if (errno < 0 || current->errno)
goto bad_syscall;
regs->reg2 = errno;
regs->reg7 = 0;
}
else
{
syscall_trace();
errno = do_syscalls(regs, syscall, narg);
if (errno < 0 || current->errno)
{
regs->reg2 = -errno;
regs->reg7 = 1;
}
else
{
regs->reg2 = errno;
regs->reg7 = 0;
}
syscall_trace();
}
return;
bad_syscall:
regs->reg2 = -errno;
regs->reg7 = 1;
return;
illegal_syscall:
regs->reg2 = ENOSYS;
regs->reg7 = 1;
return;
}
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