From a4261d4bb45022e1b8b95df13dbb05abac490165 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Tue, 12 May 2020 19:15:26 +0200 Subject: sparc: share process creation helpers between sparc and sparc64 As promised in the previous patch, this moves the process creation helpers into a common process.c file that is shared between sparc and sparc64. It allows us to get rid of quite a bit custom assembler and the to remove the separe 32bit specific sparc_do_fork() call. One thing to note, is that when clone() was called with a separate stack for the child the assembler would align it. But copy_thread() has always been doing that too so that line wasn't needed and can thus simply be removed. Signed-off-by: Christian Brauner Acked-by: David S. Miller Cc: Arnd Bergmann Cc: "David S. Miller" Cc: Guo Ren Cc: linux-csky@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: sparclinux@vger.kernel.org Link: https://lore.kernel.org/r/20200512171527.570109-3-christian.brauner@ubuntu.com --- arch/sparc/kernel/process.c | 110 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 110 insertions(+) create mode 100644 arch/sparc/kernel/process.c (limited to 'arch/sparc/kernel/process.c') diff --git a/arch/sparc/kernel/process.c b/arch/sparc/kernel/process.c new file mode 100644 index 000000000000..8bbe62d77b77 --- /dev/null +++ b/arch/sparc/kernel/process.c @@ -0,0 +1,110 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * This file handles the architecture independent parts of process handling.. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "kernel.h" + +asmlinkage long sparc_fork(struct pt_regs *regs) +{ + unsigned long orig_i1 = regs->u_regs[UREG_I1]; + long ret; + struct kernel_clone_args args = { + .exit_signal = SIGCHLD, + /* Reuse the parent's stack for the child. */ + .stack = regs->u_regs[UREG_FP], + }; + + ret = _do_fork(&args); + + /* If we get an error and potentially restart the system + * call, we're screwed because copy_thread_tls() clobbered + * the parent's %o1. So detect that case and restore it + * here. + */ + if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) + regs->u_regs[UREG_I1] = orig_i1; + + return ret; +} + +asmlinkage long sparc_vfork(struct pt_regs *regs) +{ + unsigned long orig_i1 = regs->u_regs[UREG_I1]; + long ret; + + struct kernel_clone_args args = { + .flags = CLONE_VFORK | CLONE_VM, + .exit_signal = SIGCHLD, + /* Reuse the parent's stack for the child. */ + .stack = regs->u_regs[UREG_FP], + }; + + ret = _do_fork(&args); + + /* If we get an error and potentially restart the system + * call, we're screwed because copy_thread_tls() clobbered + * the parent's %o1. So detect that case and restore it + * here. + */ + if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) + regs->u_regs[UREG_I1] = orig_i1; + + return ret; +} + +asmlinkage long sparc_clone(struct pt_regs *regs) +{ + unsigned long orig_i1 = regs->u_regs[UREG_I1]; + unsigned int flags = lower_32_bits(regs->u_regs[UREG_I0]); + long ret; + + struct kernel_clone_args args = { + .flags = (flags & ~CSIGNAL), + .exit_signal = (flags & CSIGNAL), + .tls = regs->u_regs[UREG_I3], + }; + +#ifdef CONFIG_COMPAT + if (test_thread_flag(TIF_32BIT)) { + args.pidfd = compat_ptr(regs->u_regs[UREG_I2]); + args.child_tid = compat_ptr(regs->u_regs[UREG_I4]); + args.parent_tid = compat_ptr(regs->u_regs[UREG_I2]); + } else +#endif + { + args.pidfd = (int __user *)regs->u_regs[UREG_I2]; + args.child_tid = (int __user *)regs->u_regs[UREG_I4]; + args.parent_tid = (int __user *)regs->u_regs[UREG_I2]; + } + + /* Did userspace give setup a separate stack for the child or are we + * reusing the parent's? + */ + if (regs->u_regs[UREG_I1]) + args.stack = regs->u_regs[UREG_I1]; + else + args.stack = regs->u_regs[UREG_FP]; + + ret = _do_fork(&args); + + /* If we get an error and potentially restart the system + * call, we're screwed because copy_thread_tls() clobbered + * the parent's %o1. So detect that case and restore it + * here. + */ + if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) + regs->u_regs[UREG_I1] = orig_i1; + + return ret; +} -- cgit From 714acdbd1c94e7e3ab90f6b6938f1ccb27b662f0 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 11 Jun 2020 11:04:15 +0200 Subject: arch: rename copy_thread_tls() back to copy_thread() Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls() back simply copy_thread(). It's a simpler name, and doesn't imply that only tls is copied here. This finishes an outstanding chunk of internal process creation work since we've added clone3(). Cc: linux-arch@vger.kernel.org Acked-by: Thomas Bogendoerfer A Acked-by: Stafford Horne Acked-by: Greentime Hu Acked-by: Geert Uytterhoeven A Reviewed-by: Kees Cook Signed-off-by: Christian Brauner --- arch/sparc/kernel/process.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/sparc/kernel/process.c') diff --git a/arch/sparc/kernel/process.c b/arch/sparc/kernel/process.c index 8bbe62d77b77..5234b5ccc0b9 100644 --- a/arch/sparc/kernel/process.c +++ b/arch/sparc/kernel/process.c @@ -28,7 +28,7 @@ asmlinkage long sparc_fork(struct pt_regs *regs) ret = _do_fork(&args); /* If we get an error and potentially restart the system - * call, we're screwed because copy_thread_tls() clobbered + * call, we're screwed because copy_thread() clobbered * the parent's %o1. So detect that case and restore it * here. */ @@ -53,7 +53,7 @@ asmlinkage long sparc_vfork(struct pt_regs *regs) ret = _do_fork(&args); /* If we get an error and potentially restart the system - * call, we're screwed because copy_thread_tls() clobbered + * call, we're screwed because copy_thread() clobbered * the parent's %o1. So detect that case and restore it * here. */ @@ -99,7 +99,7 @@ asmlinkage long sparc_clone(struct pt_regs *regs) ret = _do_fork(&args); /* If we get an error and potentially restart the system - * call, we're screwed because copy_thread_tls() clobbered + * call, we're screwed because copy_thread() clobbered * the parent's %o1. So detect that case and restore it * here. */ -- cgit