diff options
Diffstat (limited to 'arch/xtensa/kernel/syscalls.c')
| -rw-r--r-- | arch/xtensa/kernel/syscalls.c | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/arch/xtensa/kernel/syscalls.c b/arch/xtensa/kernel/syscalls.c new file mode 100644 index 000000000000..f20c6494c518 --- /dev/null +++ b/arch/xtensa/kernel/syscalls.c @@ -0,0 +1,269 @@ +/* + * arch/xtensa/kernel/syscall.c + * + * 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) 2001 - 2005 Tensilica Inc. + * Copyright (C) 2000 Silicon Graphics, Inc. + * Copyright (C) 1995 - 2000 by Ralf Baechle + * + * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> + * Marc Gauthier <marc@tensilica.com, marc@alumni.uwaterloo.ca> + * Chris Zankel <chris@zankel.net> + * Kevin Chea + * + */ + +#define DEBUG 0 + +#include <linux/config.h> +#include <linux/linkage.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/smp_lock.h> +#include <linux/mman.h> +#include <linux/sched.h> +#include <linux/file.h> +#include <linux/slab.h> +#include <linux/utsname.h> +#include <linux/unistd.h> +#include <linux/stringify.h> +#include <linux/syscalls.h> +#include <linux/sem.h> +#include <linux/msg.h> +#include <linux/shm.h> +#include <linux/errno.h> +#include <asm/ptrace.h> +#include <asm/signal.h> +#include <asm/uaccess.h> +#include <asm/hardirq.h> +#include <asm/mman.h> +#include <asm/shmparam.h> +#include <asm/page.h> + +extern void do_syscall_trace(void); +typedef int (*syscall_t)(void *a0,...); +extern syscall_t sys_call_table[]; +extern unsigned char sys_narg_table[]; + +/* + * sys_pipe() is the normal C calling standard for creating a pipe. It's not + * the way unix traditional does this, though. + */ + +int sys_pipe(int __user *userfds) +{ + int fd[2]; + int error; + + error = do_pipe(fd); + if (!error) { + if (copy_to_user(userfds, fd, 2 * sizeof(int))) + error = -EFAULT; + } + return error; +} + +/* + * Common code for old and new mmaps. + */ +long sys_mmap(unsigned long addr, unsigned long len, unsigned long prot, + unsigned long flags, unsigned long fd, unsigned long pgoff) +{ + int error = -EBADF; + struct file * file = NULL; + + flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE); + if (!(flags & MAP_ANONYMOUS)) { + file = fget(fd); + if (!file) + goto out; + } + + down_write(¤t->mm->mmap_sem); + error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff); + up_write(¤t->mm->mmap_sem); + + if (file) + fput(file); +out: + return error; +} + +int sys_clone(struct pt_regs *regs) +{ + unsigned long clone_flags; + unsigned long newsp; + int __user *parent_tidptr, *child_tidptr; + clone_flags = regs->areg[4]; + newsp = regs->areg[3]; + parent_tidptr = (int __user *)regs->areg[5]; + child_tidptr = (int __user *)regs->areg[6]; + if (!newsp) + newsp = regs->areg[1]; + return do_fork(clone_flags,newsp,regs,0,parent_tidptr,child_tidptr); +} + +/* + * sys_execve() executes a new program. + */ + +int sys_execve(struct pt_regs *regs) +{ + int error; + char * filename; + + filename = getname((char *) (long)regs->areg[5]); + error = PTR_ERR(filename); + if (IS_ERR(filename)) + goto out; + error = do_execve(filename, (char **) (long)regs->areg[3], + (char **) (long)regs->areg[4], regs); + putname(filename); + +out: + return error; +} + +int sys_uname(struct old_utsname * name) +{ + if (name && !copy_to_user(name, &system_utsname, sizeof (*name))) + return 0; + return -EFAULT; +} + +/* + * Build the string table for the builtin "poor man's strace". + */ + +#if DEBUG +#define SYSCALL(fun, narg) #fun, +static char *sfnames[] = { +#include "syscalls.h" +}; +#undef SYS +#endif + +void system_call (struct pt_regs *regs) +{ + syscall_t syscall; + unsigned long parm0, parm1, parm2, parm3, parm4, parm5; + int nargs, res; + unsigned int syscallnr; + int ps; + +#if DEBUG + int i; + unsigned long parms[6]; + char *sysname; +#endif + + regs->syscall = regs->areg[2]; + + do_syscall_trace(); + + /* Have to load after syscall_trace because strace + * sometimes changes regs->syscall. + */ + syscallnr = regs->syscall; + + parm0 = parm1 = parm2 = parm3 = parm4 = parm5 = 0; + + /* Restore interrupt level to syscall invoker's. + * If this were in assembly, we wouldn't disable + * interrupts in the first place: + */ + local_save_flags (ps); + local_irq_restore((ps & ~XCHAL_PS_INTLEVEL_MASK) | + (regs->ps & XCHAL_PS_INTLEVEL_MASK) ); + + if (syscallnr > __NR_Linux_syscalls) { + regs->areg[2] = -ENOSYS; + return; + } + + syscall = sys_call_table[syscallnr]; + nargs = sys_narg_table[syscallnr]; + + if (syscall == NULL) { + regs->areg[2] = -ENOSYS; + return; + } + + /* There shouldn't be more than six arguments in the table! */ + + if (nargs > 6) + panic("Internal error - too many syscall arguments (%d)!\n", + nargs); + + /* Linux takes system-call arguments in registers. The ABI + * and Xtensa software conventions require the system-call + * number in a2. If an argument exists in a2, we move it to + * the next available register. Note that for improved + * efficiency, we do NOT shift all parameters down one + * register to maintain the original order. + * + * At best case (zero arguments), we just write the syscall + * number to a2. At worst case (1 to 6 arguments), we move + * the argument in a2 to the next available register, then + * write the syscall number to a2. + * + * For clarity, the following truth table enumerates all + * possibilities. + * + * arguments syscall number arg0, arg1, arg2, arg3, arg4, arg5 + * --------- -------------- ---------------------------------- + * 0 a2 + * 1 a2 a3 + * 2 a2 a4, a3 + * 3 a2 a5, a3, a4 + * 4 a2 a6, a3, a4, a5 + * 5 a2 a7, a3, a4, a5, a6 + * 6 a2 a8, a3, a4, a5, a6, a7 + */ + if (nargs) { + parm0 = regs->areg[nargs+2]; + parm1 = regs->areg[3]; + parm2 = regs->areg[4]; + parm3 = regs->areg[5]; + parm4 = regs->areg[6]; + parm5 = regs->areg[7]; + } else /* nargs == 0 */ + parm0 = (unsigned long) regs; + +#if DEBUG + parms[0] = parm0; + parms[1] = parm1; + parms[2] = parm2; + parms[3] = parm3; + parms[4] = parm4; + parms[5] = parm5; + + sysname = sfnames[syscallnr]; + if (strncmp(sysname, "sys_", 4) == 0) + sysname = sysname + 4; + + printk("\017SYSCALL:I:%x:%d:%s %s(", regs->pc, current->pid, + current->comm, sysname); + for (i = 0; i < nargs; i++) + printk((i>0) ? ", %#lx" : "%#lx", parms[i]); + printk(")\n"); +#endif + + res = syscall((void *)parm0, parm1, parm2, parm3, parm4, parm5); + +#if DEBUG + printk("\017SYSCALL:O:%d:%s %s(",current->pid, current->comm, sysname); + for (i = 0; i < nargs; i++) + printk((i>0) ? ", %#lx" : "%#lx", parms[i]); + if (res < 4096) + printk(") = %d\n", res); + else + printk(") = %#x\n", res); +#endif /* DEBUG */ + + regs->areg[2] = res; + do_syscall_trace(); +} |