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/mips/kernel/process.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'arch/mips/kernel/process.c') diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index a572d097b16b..35b912bce429 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -109,7 +109,6 @@ 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 kthread_arg = args->stack_size; unsigned long tls = args->tls; struct thread_info *ti = task_thread_info(p); struct pt_regs *childregs, *regs = current_pt_regs(); @@ -122,12 +121,12 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) /* Put the stack after the struct pt_regs. */ childksp = (unsigned long) childregs; p->thread.cp0_status = (read_c0_status() & ~(ST0_CU2|ST0_CU1)) | ST0_KERNEL_CUMASK; - if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) { + if (unlikely(args->fn)) { /* kernel thread */ unsigned long status = p->thread.cp0_status; memset(childregs, 0, sizeof(struct pt_regs)); - p->thread.reg16 = usp; /* fn */ - p->thread.reg17 = kthread_arg; + p->thread.reg16 = (unsigned long)args->fn; + p->thread.reg17 = (unsigned long)args->fn_arg; p->thread.reg29 = childksp; p->thread.reg31 = (unsigned long) ret_from_kernel_thread; #if defined(CONFIG_CPU_R3000) -- cgit v1.2.3-70-g09d2