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Diffstat (limited to 'arch/powerpc/include/asm/syscall.h')
| -rw-r--r-- | arch/powerpc/include/asm/syscall.h | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/syscall.h b/arch/powerpc/include/asm/syscall.h new file mode 100644 index 000000000..ba0f88f3a --- /dev/null +++ b/arch/powerpc/include/asm/syscall.h @@ -0,0 +1,131 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Access to user system call parameters and results + * + * Copyright (C) 2008 Red Hat, Inc. All rights reserved. + * + * See asm-generic/syscall.h for descriptions of what we must do here. + */ + +#ifndef _ASM_SYSCALL_H +#define _ASM_SYSCALL_H 1 + +#include <uapi/linux/audit.h> +#include <linux/sched.h> +#include <linux/thread_info.h> + +/* ftrace syscalls requires exporting the sys_call_table */ +extern const unsigned long sys_call_table[]; +extern const unsigned long compat_sys_call_table[]; + +static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs) +{ + /* + * Note that we are returning an int here. That means 0xffffffff, ie. + * 32-bit negative 1, will be interpreted as -1 on a 64-bit kernel. + * This is important for seccomp so that compat tasks can set r0 = -1 + * to reject the syscall. + */ + if (trap_is_syscall(regs)) + return regs->gpr[0]; + else + return -1; +} + +static inline void syscall_rollback(struct task_struct *task, + struct pt_regs *regs) +{ + regs->gpr[3] = regs->orig_gpr3; +} + +static inline long syscall_get_error(struct task_struct *task, + struct pt_regs *regs) +{ + if (trap_is_scv(regs)) { + unsigned long error = regs->gpr[3]; + + return IS_ERR_VALUE(error) ? error : 0; + } else { + /* + * If the system call failed, + * regs->gpr[3] contains a positive ERRORCODE. + */ + return (regs->ccr & 0x10000000UL) ? -regs->gpr[3] : 0; + } +} + +static inline long syscall_get_return_value(struct task_struct *task, + struct pt_regs *regs) +{ + return regs->gpr[3]; +} + +static inline void syscall_set_return_value(struct task_struct *task, + struct pt_regs *regs, + int error, long val) +{ + if (trap_is_scv(regs)) { + regs->gpr[3] = (long) error ?: val; + } else { + /* + * In the general case it's not obvious that we must deal with + * CCR here, as the syscall exit path will also do that for us. + * However there are some places, eg. the signal code, which + * check ccr to decide if the value in r3 is actually an error. + */ + if (error) { + regs->ccr |= 0x10000000L; + regs->gpr[3] = error; + } else { + regs->ccr &= ~0x10000000L; + regs->gpr[3] = val; + } + } +} + +static inline void syscall_get_arguments(struct task_struct *task, + struct pt_regs *regs, + unsigned long *args) +{ + unsigned long val, mask = -1UL; + unsigned int n = 6; + +#ifdef CONFIG_COMPAT + if (test_tsk_thread_flag(task, TIF_32BIT)) + mask = 0xffffffff; +#endif + while (n--) { + if (n == 0) + val = regs->orig_gpr3; + else + val = regs->gpr[3 + n]; + + args[n] = val & mask; + } +} + +static inline void syscall_set_arguments(struct task_struct *task, + struct pt_regs *regs, + const unsigned long *args) +{ + memcpy(®s->gpr[3], args, 6 * sizeof(args[0])); + + /* Also copy the first argument into orig_gpr3 */ + regs->orig_gpr3 = args[0]; +} + +static inline int syscall_get_arch(struct task_struct *task) +{ + int arch; + + if (IS_ENABLED(CONFIG_PPC64) && !test_tsk_thread_flag(task, TIF_32BIT)) + arch = AUDIT_ARCH_PPC64; + else + arch = AUDIT_ARCH_PPC; + +#ifdef __LITTLE_ENDIAN__ + arch |= __AUDIT_ARCH_LE; +#endif + return arch; +} +#endif /* _ASM_SYSCALL_H */ |