acrn-kernel/arch/um/include/asm/syscall-generic.h

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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Access to user system call parameters and results
*
* See asm-generic/syscall.h for function descriptions.
*
* Copyright (C) 2015 Mickaël Salaün <mic@digikod.net>
*/
#ifndef __UM_SYSCALL_GENERIC_H
#define __UM_SYSCALL_GENERIC_H
#include <asm/ptrace.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <sysdep/ptrace.h>
static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
{
return PT_REGS_SYSCALL_NR(regs);
}
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
/* do nothing */
}
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
const long error = regs_return_value(regs);
return IS_ERR_VALUE(error) ? error : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
return regs_return_value(regs);
}
static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
PT_REGS_SET_SYSCALL_RETURN(regs, (long) error ?: val);
}
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned long *args)
{
const struct uml_pt_regs *r = &regs->regs;
syscalls: Remove start and number from syscall_get_arguments() args At Linux Plumbers, Andy Lutomirski approached me and pointed out that the function call syscall_get_arguments() implemented in x86 was horribly written and not optimized for the standard case of passing in 0 and 6 for the starting index and the number of system calls to get. When looking at all the users of this function, I discovered that all instances pass in only 0 and 6 for these arguments. Instead of having this function handle different cases that are never used, simply rewrite it to return the first 6 arguments of a system call. This should help out the performance of tracing system calls by ptrace, ftrace and perf. Link: http://lkml.kernel.org/r/20161107213233.754809394@goodmis.org Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Dave Martin <dave.martin@arm.com> Cc: "Dmitry V. Levin" <ldv@altlinux.org> Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86 Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2016-11-08 05:26:37 +08:00
*args++ = UPT_SYSCALL_ARG1(r);
*args++ = UPT_SYSCALL_ARG2(r);
*args++ = UPT_SYSCALL_ARG3(r);
*args++ = UPT_SYSCALL_ARG4(r);
*args++ = UPT_SYSCALL_ARG5(r);
*args = UPT_SYSCALL_ARG6(r);
}
static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
const unsigned long *args)
{
struct uml_pt_regs *r = &regs->regs;
syscalls: Remove start and number from syscall_set_arguments() args After removing the start and count arguments of syscall_get_arguments() it seems reasonable to remove them from syscall_set_arguments(). Note, as of today, there are no users of syscall_set_arguments(). But we are told that there will be soon. But for now, at least make it consistent with syscall_get_arguments(). Link: http://lkml.kernel.org/r/20190327222014.GA32540@altlinux.org Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Dave Martin <dave.martin@arm.com> Cc: "Dmitry V. Levin" <ldv@altlinux.org> Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86 Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-28 08:07:31 +08:00
UPT_SYSCALL_ARG1(r) = *args++;
UPT_SYSCALL_ARG2(r) = *args++;
UPT_SYSCALL_ARG3(r) = *args++;
UPT_SYSCALL_ARG4(r) = *args++;
UPT_SYSCALL_ARG5(r) = *args++;
UPT_SYSCALL_ARG6(r) = *args;
}
/* See arch/x86/um/asm/syscall.h for syscall_get_arch() definition. */
#endif /* __UM_SYSCALL_GENERIC_H */