arch/score/kernel/sys_score.c

   1 /*
   2  * arch/score/kernel/syscall.c
   3  *
   4  * Score Processor version.
   5  *
   6  * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
   7  *  Chen Liqin <liqin.chen@sunplusct.com>
   8  *  Lennox Wu <lennox.wu@sunplusct.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, see the file COPYING, or write
  22  * to the Free Software Foundation, Inc.,
  23  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  24  */
  25
  26 #include <linux/file.h>
  27 #include <linux/fs.h>
  28 #include <linux/mman.h>
  29 #include <linux/module.h>
  30 #include <linux/unistd.h>
  31 #include <linux/syscalls.h>
  32 #include <asm/syscalls.h>
  33
  34 unsigned long shm_align_mask = PAGE_SIZE - 1;
  35 EXPORT_SYMBOL(shm_align_mask);
  36
  37 asmlinkage unsigned long
  38 sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
  39           unsigned long flags, unsigned long fd, unsigned long pgoff)
  40 {
  41         int error = -EBADF;
  42         struct file *file = NULL;
  43
  44         if (pgoff & (~PAGE_MASK >> 12))
  45                 return -EINVAL;
  46
  47         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  48         if (!(flags & MAP_ANONYMOUS)) {
  49                 file = fget(fd);
  50                 if (!file)
  51                         return error;
  52         }
  53
  54         down_write(&current->mm->mmap_sem);
  55         error = do_mmap_pgoff(file, addr, len, prot, flags,
  56                         pgoff >> (PAGE_SHIFT - 12));
  57         up_write(&current->mm->mmap_sem);
  58
  59         if (file)
  60                 fput(file);
  61
  62         return error;
  63 }
  64
  65 /*
  66  * Clone a task - this clones the calling program thread.
  67  * This is called indirectly via a small wrapper
  68  */
  69 int score_clone(struct pt_regs *regs)
  70 {
  71         unsigned long clone_flags;
  72         unsigned long newsp;
  73         int __user *parent_tidptr, *child_tidptr;
  74
  75         clone_flags = regs->regs[4];
  76         newsp = regs->regs[5];
  77         if (!newsp)
  78                 newsp = regs->regs[0];
  79         parent_tidptr = (int __user *)regs->regs[6];
  80         child_tidptr = (int __user *)regs->regs[8];
  81
  82         return do_fork(clone_flags, newsp, regs, 0,
  83                         parent_tidptr, child_tidptr);
  84 }
  85
  86 /*
  87  * sys_execve() executes a new program.
  88  * This is called indirectly via a small wrapper
  89  */
  90 asmlinkage long
  91 score_execve(struct pt_regs *regs)
  92 {
  93         int error;
  94         char *filename;
  95
  96         filename = getname((char __user*)regs->regs[4]);
  97         error = PTR_ERR(filename);
  98         if (IS_ERR(filename))
  99                 return error;
 100
 101         error = do_execve(filename, (char __user *__user*)regs->regs[5],
 102                           (char __user *__user *) regs->regs[6], regs);
 103
 104         putname(filename);
 105         return error;
 106 }
 107
 108 /*
 109  * If we ever come here the user sp is bad.  Zap the process right away.
 110  * Due to the bad stack signaling wouldn't work.
 111  */
 112 void bad_stack(void)
 113 {
 114         do_exit(SIGSEGV);
 115 }
 116
 117 /*
 118  * Do a system call from kernel instead of calling sys_execve so we
 119  * end up with proper pt_regs.
 120  */
 121 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 122 {
 123         register unsigned long __r4 asm("r4") = (unsigned long) filename;
 124         register unsigned long __r5 asm("r5") = (unsigned long) argv;
 125         register unsigned long __r6 asm("r6") = (unsigned long) envp;
 126         register unsigned long __r7 asm("r7");
 127
 128         __asm__ __volatile__ (" \n"
 129                 "ldi    r27, %5         \n"
 130                 "syscall                \n"
 131                 "mv     %0, r4          \n"
 132                 "mv     %1, r7          \n"
 133                 : "=&r" (__r4), "=r" (__r7)
 134                 : "r" (__r4), "r" (__r5), "r" (__r6), "i" (__NR_execve)
 135                 : "r8", "r9", "r10", "r11", "r22", "r23", "r24", "r25",
 136                   "r26", "r27", "memory");
 137
 138         if (__r7 == 0)
 139                 return __r4;
 140
 141         return -__r4;
 142 }