diff options
Diffstat (limited to 'lib/syscall.c')
| -rw-r--r-- | lib/syscall.c | 57 | 
1 files changed, 25 insertions, 32 deletions
diff --git a/lib/syscall.c b/lib/syscall.c index 1a7077f20eae..fb328e7ccb08 100644 --- a/lib/syscall.c +++ b/lib/syscall.c @@ -5,16 +5,14 @@  #include <linux/export.h>  #include <asm/syscall.h> -static int collect_syscall(struct task_struct *target, long *callno, -			   unsigned long args[6], unsigned int maxargs, -			   unsigned long *sp, unsigned long *pc) +static int collect_syscall(struct task_struct *target, struct syscall_info *info)  {  	struct pt_regs *regs;  	if (!try_get_task_stack(target)) {  		/* Task has no stack, so the task isn't in a syscall. */ -		*sp = *pc = 0; -		*callno = -1; +		memset(info, 0, sizeof(*info)); +		info->data.nr = -1;  		return 0;  	} @@ -24,12 +22,13 @@ static int collect_syscall(struct task_struct *target, long *callno,  		return -EAGAIN;  	} -	*sp = user_stack_pointer(regs); -	*pc = instruction_pointer(regs); +	info->sp = user_stack_pointer(regs); +	info->data.instruction_pointer = instruction_pointer(regs); -	*callno = syscall_get_nr(target, regs); -	if (*callno != -1L && maxargs > 0) -		syscall_get_arguments(target, regs, 0, maxargs, args); +	info->data.nr = syscall_get_nr(target, regs); +	if (info->data.nr != -1L) +		syscall_get_arguments(target, regs, +				      (unsigned long *)&info->data.args[0]);  	put_task_stack(target);  	return 0; @@ -38,41 +37,35 @@ static int collect_syscall(struct task_struct *target, long *callno,  /**   * task_current_syscall - Discover what a blocked task is doing.   * @target:		thread to examine - * @callno:		filled with system call number or -1 - * @args:		filled with @maxargs system call arguments - * @maxargs:		number of elements in @args to fill - * @sp:			filled with user stack pointer - * @pc:			filled with user PC + * @info:		structure with the following fields: + *			 .sp        - filled with user stack pointer + *			 .data.nr   - filled with system call number or -1 + *			 .data.args - filled with @maxargs system call arguments + *			 .data.instruction_pointer - filled with user PC   * - * If @target is blocked in a system call, returns zero with *@callno - * set to the the call's number and @args filled in with its arguments. - * Registers not used for system call arguments may not be available and - * it is not kosher to use &struct user_regset calls while the system + * If @target is blocked in a system call, returns zero with @info.data.nr + * set to the the call's number and @info.data.args filled in with its + * arguments. Registers not used for system call arguments may not be available + * and it is not kosher to use &struct user_regset calls while the system   * call is still in progress.  Note we may get this result if @target   * has finished its system call but not yet returned to user mode, such   * as when it's stopped for signal handling or syscall exit tracing.   *   * If @target is blocked in the kernel during a fault or exception, - * returns zero with *@callno set to -1 and does not fill in @args. - * If so, it's now safe to examine @target using &struct user_regset - * get() calls as long as we're sure @target won't return to user mode. + * returns zero with *@info.data.nr set to -1 and does not fill in + * @info.data.args. If so, it's now safe to examine @target using + * &struct user_regset get() calls as long as we're sure @target won't return + * to user mode.   *   * Returns -%EAGAIN if @target does not remain blocked. - * - * Returns -%EINVAL if @maxargs is too large (maximum is six).   */ -int task_current_syscall(struct task_struct *target, long *callno, -			 unsigned long args[6], unsigned int maxargs, -			 unsigned long *sp, unsigned long *pc) +int task_current_syscall(struct task_struct *target, struct syscall_info *info)  {  	long state;  	unsigned long ncsw; -	if (unlikely(maxargs > 6)) -		return -EINVAL; -  	if (target == current) -		return collect_syscall(target, callno, args, maxargs, sp, pc); +		return collect_syscall(target, info);  	state = target->state;  	if (unlikely(!state)) @@ -80,7 +73,7 @@ int task_current_syscall(struct task_struct *target, long *callno,  	ncsw = wait_task_inactive(target, state);  	if (unlikely(!ncsw) || -	    unlikely(collect_syscall(target, callno, args, maxargs, sp, pc)) || +	    unlikely(collect_syscall(target, info)) ||  	    unlikely(wait_task_inactive(target, state) != ncsw))  		return -EAGAIN;  | 
