Files
android_kernel_xiaomi_sm8450/arch/nds32/include/asm/syscall.h
Linus Torvalds 4489da7183 Merge tag 'nds32-for-linus-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux
Pull nds32 updates from Greentime Hu:

 - Clean up codes and Makefile

 - Fix a vDSO bug

 - Remove useless functions/header files

 - Update git repo path in MAINTAINERS

* tag 'nds32-for-linus-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux:
  nds32: Fix vDSO clock_getres()
  MAINTAINERS: update nds32 git repo path
  nds32: don't export low-level cache flushing routines
  arch: nds32: Kconfig: pedantic formatting
  nds32: fix semicolon code style issue
  nds32: vdso: drop unnecessary cc-ldoption
  nds32: remove unused generic-y += cmpxchg-local.h
  nds32: Use the correct style for SPDX License Identifier
  nds32: remove __virt_to_bus and __bus_to_virt
  nds32: vdso: fix and clean-up Makefile
  nds32: add vmlinux.lds and vdso.so to .gitignore
  nds32: ex-exit: Remove unneeded need_resched() loop
  nds32/io: Remove useless definition of mmiowb()
  nds32: Removed unused thread flag TIF_USEDFPU
2019-05-17 10:17:29 -07:00

158 lines
5.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
// Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
// Copyright (C) 2005-2017 Andes Technology Corporation
#ifndef _ASM_NDS32_SYSCALL_H
#define _ASM_NDS32_SYSCALL_H 1
#include <uapi/linux/audit.h>
#include <linux/err.h>
struct task_struct;
struct pt_regs;
/**
* syscall_get_nr - find what system call a task is executing
* @task: task of interest, must be blocked
* @regs: task_pt_regs() of @task
*
* If @task is executing a system call or is at system call
* tracing about to attempt one, returns the system call number.
* If @task is not executing a system call, i.e. it's blocked
* inside the kernel for a fault or signal, returns -1.
*
* Note this returns int even on 64-bit machines. Only 32 bits of
* system call number can be meaningful. If the actual arch value
* is 64 bits, this truncates to 32 bits so 0xffffffff means -1.
*
* It's only valid to call this when @task is known to be blocked.
*/
int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
{
return regs->syscallno;
}
/**
* syscall_rollback - roll back registers after an aborted system call
* @task: task of interest, must be in system call exit tracing
* @regs: task_pt_regs() of @task
*
* It's only valid to call this when @task is stopped for system
* call exit tracing (due to TIF_SYSCALL_TRACE or TIF_SYSCALL_AUDIT),
* after tracehook_report_syscall_entry() returned nonzero to prevent
* the system call from taking place.
*
* This rolls back the register state in @regs so it's as if the
* system call instruction was a no-op. The registers containing
* the system call number and arguments are as they were before the
* system call instruction. This may not be the same as what the
* register state looked like at system call entry tracing.
*/
void syscall_rollback(struct task_struct *task, struct pt_regs *regs)
{
regs->uregs[0] = regs->orig_r0;
}
/**
* syscall_get_error - check result of traced system call
* @task: task of interest, must be blocked
* @regs: task_pt_regs() of @task
*
* Returns 0 if the system call succeeded, or -ERRORCODE if it failed.
*
* It's only valid to call this when @task is stopped for tracing on exit
* from a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT.
*/
long syscall_get_error(struct task_struct *task, struct pt_regs *regs)
{
unsigned long error = regs->uregs[0];
return IS_ERR_VALUE(error) ? error : 0;
}
/**
* syscall_get_return_value - get the return value of a traced system call
* @task: task of interest, must be blocked
* @regs: task_pt_regs() of @task
*
* Returns the return value of the successful system call.
* This value is meaningless if syscall_get_error() returned nonzero.
*
* It's only valid to call this when @task is stopped for tracing on exit
* from a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT.
*/
long syscall_get_return_value(struct task_struct *task, struct pt_regs *regs)
{
return regs->uregs[0];
}
/**
* syscall_set_return_value - change the return value of a traced system call
* @task: task of interest, must be blocked
* @regs: task_pt_regs() of @task
* @error: negative error code, or zero to indicate success
* @val: user return value if @error is zero
*
* This changes the results of the system call that user mode will see.
* If @error is zero, the user sees a successful system call with a
* return value of @val. If @error is nonzero, it's a negated errno
* code; the user sees a failed system call with this errno code.
*
* It's only valid to call this when @task is stopped for tracing on exit
* from a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT.
*/
void syscall_set_return_value(struct task_struct *task, struct pt_regs *regs,
int error, long val)
{
regs->uregs[0] = (long)error ? error : val;
}
/**
* syscall_get_arguments - extract system call parameter values
* @task: task of interest, must be blocked
* @regs: task_pt_regs() of @task
* @args: array filled with argument values
*
* Fetches 6 arguments to the system call (from 0 through 5). The first
* argument is stored in @args[0], and so on.
*
* It's only valid to call this when @task is stopped for tracing on
* entry to a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT.
*/
#define SYSCALL_MAX_ARGS 6
void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
unsigned long *args)
{
args[0] = regs->orig_r0;
args++;
memcpy(args, &regs->uregs[0] + 1, 5 * sizeof(args[0]));
}
/**
* syscall_set_arguments - change system call parameter value
* @task: task of interest, must be in system call entry tracing
* @regs: task_pt_regs() of @task
* @args: array of argument values to store
*
* Changes 6 arguments to the system call. The first argument gets value
* @args[0], and so on.
*
* It's only valid to call this when @task is stopped for tracing on
* entry to a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT.
*/
void syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
const unsigned long *args)
{
regs->orig_r0 = args[0];
args++;
memcpy(&regs->uregs[0] + 1, args, 5 * sizeof(args[0]));
}
static inline int
syscall_get_arch(struct task_struct *task)
{
return IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)
? AUDIT_ARCH_NDS32BE : AUDIT_ARCH_NDS32;
}
#endif /* _ASM_NDS32_SYSCALL_H */