s390: switch to generic fork/vfork/clone (87f1ca8f) · Commits · 戴 / test

arch/s390/Kconfig

+1 −0

Original line number	Diff line number	Diff line
		@@ -141,6 +141,7 @@ config S390
		select GENERIC_KERNEL_EXECVE
		select HAVE_MOD_ARCH_SPECIFIC
		select MODULES_USE_ELF_RELA
		select CLONE_BACKWARDS2

		config SCHED_OMIT_FRAME_POINTER
		def_bool y

arch/s390/include/asm/unistd.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -54,6 +54,9 @@
		# define __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
		# endif
		#define __ARCH_WANT_SYS_EXECVE
		#define __ARCH_WANT_SYS_FORK
		#define __ARCH_WANT_SYS_VFORK
		#define __ARCH_WANT_SYS_CLONE

		/*
		* "Conditional" syscalls

arch/s390/kernel/process.c

+10 −42

Original line number	Diff line number	Diff line
		@@ -118,7 +118,7 @@ void release_thread(struct task_struct *dead_task)

		int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
		unsigned long arg,
		struct task_struct p, struct pt_regs regs)
		struct task_struct p, struct pt_regs unused)
		{
		struct thread_info *ti;
		struct fake_frame
		@@ -150,7 +150,7 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
		frame->sf.gprs[9] = (unsigned long) frame;

		/* Store access registers to kernel stack of new process. */
		if (unlikely(!regs)) {
		if (unlikely(p->flags & PF_KTHREAD)) {
		/* kernel thread */
		memset(&frame->childregs, 0, sizeof(struct pt_regs));
		frame->childregs.psw.mask = psw_kernel_bits \| PSW_MASK_DAT \|
		@@ -164,8 +164,9 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,

		return 0;
		}
		frame->childregs = *regs;
		frame->childregs = *current_pt_regs();
		frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */
		if (new_stackp)
		frame->childregs.gprs[15] = new_stackp;

		/* Don't copy runtime instrumentation info */
		@@ -183,57 +184,24 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
		sizeof(s390_fp_regs));
		/* Set a new TLS ? */
		if (clone_flags & CLONE_SETTLS)
		p->thread.acrs[0] = regs->gprs[6];
		p->thread.acrs[0] = frame->childregs.gprs[6];
		#else /* CONFIG_64BIT */
		/* Save the fpu registers to new thread structure. */
		save_fp_regs(&p->thread.fp_regs);
		/* Set a new TLS ? */
		if (clone_flags & CLONE_SETTLS) {
		unsigned long tls = frame->childregs.gprs[6];
		if (is_compat_task()) {
		p->thread.acrs[0] = (unsigned int) regs->gprs[6];
		p->thread.acrs[0] = (unsigned int)tls;
		} else {
		p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32);
		p->thread.acrs[1] = (unsigned int) regs->gprs[6];
		p->thread.acrs[0] = (unsigned int)(tls >> 32);
		p->thread.acrs[1] = (unsigned int)tls;
		}
		}
		#endif /* CONFIG_64BIT */
		return 0;
		}

		SYSCALL_DEFINE0(fork)
		{
		struct pt_regs *regs = task_pt_regs(current);
		return do_fork(SIGCHLD, regs->gprs[15], regs, 0, NULL, NULL);
		}

		SYSCALL_DEFINE4(clone, unsigned long, newsp, unsigned long, clone_flags,
		int __user , parent_tidptr, int __user , child_tidptr)
		{
		struct pt_regs *regs = task_pt_regs(current);

		if (!newsp)
		newsp = regs->gprs[15];
		return do_fork(clone_flags, newsp, regs, 0,
		parent_tidptr, child_tidptr);
		}

		/*
		* This is trivial, and on the face of it looks like it
		* could equally well be done in user mode.
		*
		* Not so, for quite unobvious reasons - register pressure.
		* In user mode vfork() cannot have a stack frame, and if
		* done by calling the "clone()" system call directly, you
		* do not have enough call-clobbered registers to hold all
		* the information you need.
		*/
		SYSCALL_DEFINE0(vfork)
		{
		struct pt_regs *regs = task_pt_regs(current);
		return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD,
		regs->gprs[15], regs, 0, NULL, NULL);
		}

		asmlinkage void execve_tail(void)
		{
		current->thread.fp_regs.fpc = 0;

Admin message