From 5bd2e97c868a8a44470950ed01846cab6328e540 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 12 Apr 2022 10:18:48 -0500 Subject: fork: Generalize PF_IO_WORKER handling Add fn and fn_arg members into struct kernel_clone_args and test for them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER). This allows any task that wants to be a user space task that only runs in kernel mode to use this functionality. The code on x86 is an exception and still retains a PF_KTHREAD test because x86 unlikely everything else handles kthreads slightly differently than user space tasks that start with a function. The functions that created tasks that start with a function have been updated to set ".fn" and ".fn_arg" instead of ".stack" and ".stack_size". These functions are fork_idle(), create_io_thread(), kernel_thread(), and user_mode_thread(). Link: https://lkml.kernel.org/r/20220506141512.516114-4-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" --- arch/nios2/kernel/process.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'arch/nios2') diff --git a/arch/nios2/kernel/process.c b/arch/nios2/kernel/process.c index 98c4bfe972e0..29593b98567d 100644 --- a/arch/nios2/kernel/process.c +++ b/arch/nios2/kernel/process.c @@ -104,7 +104,6 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) { unsigned long clone_flags = args->flags; unsigned long usp = args->stack; - unsigned long arg = args->stack_size; unsigned long tls = args->tls; struct pt_regs *childregs = task_pt_regs(p); struct pt_regs *regs; @@ -112,12 +111,12 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) struct switch_stack *childstack = ((struct switch_stack *)childregs) - 1; - if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) { + if (unlikely(args->fn)) { memset(childstack, 0, sizeof(struct switch_stack) + sizeof(struct pt_regs)); - childstack->r16 = usp; /* fn */ - childstack->r17 = arg; + childstack->r16 = (unsigned long) args->fn; + childstack->r17 = (unsigned long) args->fn_arg; childstack->ra = (unsigned long) ret_from_kernel_thread; childregs->estatus = STATUS_PIE; childregs->sp = (unsigned long) childstack; -- cgit v1.2.3