diff options
Diffstat (limited to 'arch/alpha/kernel/process.c')
| -rw-r--r-- | arch/alpha/kernel/process.c | 63 |
1 files changed, 14 insertions, 49 deletions
diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c index 51987dcf79b..63d27fb9b02 100644 --- a/arch/alpha/kernel/process.c +++ b/arch/alpha/kernel/process.c @@ -235,51 +235,27 @@ release_thread(struct task_struct *dead_task) } /* - * "alpha_clone()".. By the time we get here, the - * non-volatile registers have also been saved on the - * stack. We do some ugly pointer stuff here.. (see - * also copy_thread) - * - * Notice that "fork()" is implemented in terms of clone, - * with parameters (SIGCHLD, 0). - */ -int -alpha_clone(unsigned long clone_flags, unsigned long usp, - int __user *parent_tid, int __user *child_tid, - unsigned long tls_value, struct pt_regs *regs) -{ - if (!usp) - usp = rdusp(); - - return do_fork(clone_flags, usp, regs, 0, parent_tid, child_tid); -} - -int -alpha_vfork(struct pt_regs *regs) -{ - return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), - regs, 0, NULL, NULL); -} - -/* * Copy an alpha thread.. */ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg, - struct task_struct * p, struct pt_regs * regs) + struct task_struct *p) { extern void ret_from_fork(void); extern void ret_from_kernel_thread(void); struct thread_info *childti = task_thread_info(p); struct pt_regs *childregs = task_pt_regs(p); + struct pt_regs *regs = current_pt_regs(); struct switch_stack *childstack, *stack; - unsigned long settls; childstack = ((struct switch_stack *) childregs) - 1; - if (unlikely(!regs)) { + childti->pcb.ksp = (unsigned long) childstack; + childti->pcb.flags = 1; /* set FEN, clear everything else */ + + if (unlikely(p->flags & PF_KTHREAD)) { /* kernel thread */ memset(childstack, 0, sizeof(struct switch_stack) + sizeof(struct pt_regs)); @@ -288,12 +264,17 @@ copy_thread(unsigned long clone_flags, unsigned long usp, childstack->r10 = arg; childregs->hae = alpha_mv.hae_cache, childti->pcb.usp = 0; - childti->pcb.ksp = (unsigned long) childstack; - childti->pcb.flags = 1; /* set FEN, clear everything else */ return 0; } + /* Note: if CLONE_SETTLS is not set, then we must inherit the + value from the parent, which will have been set by the block + copy in dup_task_struct. This is non-intuitive, but is + required for proper operation in the case of a threaded + application calling fork. */ + if (clone_flags & CLONE_SETTLS) + childti->pcb.unique = regs->r20; + childti->pcb.usp = usp ?: rdusp(); *childregs = *regs; - settls = regs->r20; childregs->r0 = 0; childregs->r19 = 0; childregs->r20 = 1; /* OSF/1 has some strange fork() semantics. */ @@ -301,22 +282,6 @@ copy_thread(unsigned long clone_flags, unsigned long usp, stack = ((struct switch_stack *) regs) - 1; *childstack = *stack; childstack->r26 = (unsigned long) ret_from_fork; - childti->pcb.usp = usp; - childti->pcb.ksp = (unsigned long) childstack; - childti->pcb.flags = 1; /* set FEN, clear everything else */ - - /* Set a new TLS for the child thread? Peek back into the - syscall arguments that we saved on syscall entry. Oops, - except we'd have clobbered it with the parent/child set - of r20. Read the saved copy. */ - /* Note: if CLONE_SETTLS is not set, then we must inherit the - value from the parent, which will have been set by the block - copy in dup_task_struct. This is non-intuitive, but is - required for proper operation in the case of a threaded - application calling fork. */ - if (clone_flags & CLONE_SETTLS) - childti->pcb.unique = settls; - return 0; } |