From: Vineet Gupta Date: Fri, 18 Jan 2013 09:42:18 +0000 (+0530) Subject: ARC: Syscall support (no-legacy-syscall ABI) X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=4adeefe161a74369e44cc8e663f240ece0470dc3;p=linux-beck.git ARC: Syscall support (no-legacy-syscall ABI) This includes support for generic clone/for/vfork/execve Signed-off-by: Vineet Gupta Cc: Arnd Bergmann Cc: Al Viro Acked-by: Arnd Bergmann --- diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index b0b09aea98ff..8789de1c7c8f 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -9,6 +9,7 @@ config ARC def_bool y select ARCH_NO_VIRT_TO_BUS + select CLONE_BACKWARDS # ARC Busybox based initramfs absolutely relies on DEVTMPFS for /dev select DEVTMPFS if !INITRAMFS_SOURCE="" select GENERIC_ATOMIC64 diff --git a/arch/arc/include/asm/ptrace.h b/arch/arc/include/asm/ptrace.h index 446e55eee7be..4c9359477ded 100644 --- a/arch/arc/include/asm/ptrace.h +++ b/arch/arc/include/asm/ptrace.h @@ -86,6 +86,11 @@ struct callee_regs { sp = -1; \ sp; \ }) + +/* return 1 if in syscall, 0 if Intr or Exception */ +#define in_syscall(regs) (((regs->orig_r8) >= 0 && \ + (regs->orig_r8 <= NR_syscalls)) ? 1 : 0) + #endif /* !__ASSEMBLY__ */ #endif /* __KERNEL__ */ diff --git a/arch/arc/include/asm/syscall.h b/arch/arc/include/asm/syscall.h new file mode 100644 index 000000000000..33ab3048e9b2 --- /dev/null +++ b/arch/arc/include/asm/syscall.h @@ -0,0 +1,72 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef _ASM_ARC_SYSCALL_H +#define _ASM_ARC_SYSCALL_H 1 + +#include +#include +#include +#include /* in_syscall() */ + +static inline long +syscall_get_nr(struct task_struct *task, struct pt_regs *regs) +{ + if (user_mode(regs) && in_syscall(regs)) + return regs->orig_r8; + else + return -1; +} + +static inline void +syscall_rollback(struct task_struct *task, struct pt_regs *regs) +{ + /* XXX: I can't fathom how pt_regs->r8 will be clobbered ? */ + regs->r8 = regs->orig_r8; +} + +static inline long +syscall_get_error(struct task_struct *task, struct pt_regs *regs) +{ + /* 0 if syscall succeeded, otherwise -Errorcode */ + return IS_ERR_VALUE(regs->r0) ? regs->r0 : 0; +} + +static inline long +syscall_get_return_value(struct task_struct *task, struct pt_regs *regs) +{ + return regs->r0; +} + +static inline void +syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, + int error, long val) +{ + regs->r0 = (long) error ?: val; +} + +/* + * @i: argument index [0,5] + * @n: number of arguments; n+i must be [1,6]. + */ +static inline void +syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, + unsigned int i, unsigned int n, unsigned long *args) +{ + unsigned long *inside_ptregs = &(regs->r0); + inside_ptregs -= i; + + BUG_ON((i + n) > 6); + + while (n--) { + args[i++] = (*inside_ptregs); + inside_ptregs--; + } +} + +#endif diff --git a/arch/arc/include/asm/syscalls.h b/arch/arc/include/asm/syscalls.h new file mode 100644 index 000000000000..e53a5340ba4f --- /dev/null +++ b/arch/arc/include/asm/syscalls.h @@ -0,0 +1,29 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef _ASM_ARC_SYSCALLS_H +#define _ASM_ARC_SYSCALLS_H 1 + +#ifdef __KERNEL__ + +#include +#include +#include + +int sys_clone_wrapper(int, int, int, int, int); +int sys_fork_wrapper(void); +int sys_vfork_wrapper(void); +int sys_cacheflush(uint32_t, uint32_t uint32_t); +int sys_arc_settls(void *); +int sys_arc_gettls(void); + +#include + +#endif /* __KERNEL__ */ + +#endif diff --git a/arch/arc/include/asm/unistd.h b/arch/arc/include/asm/unistd.h new file mode 100644 index 000000000000..6f30484f34b7 --- /dev/null +++ b/arch/arc/include/asm/unistd.h @@ -0,0 +1,34 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +/******** no-legacy-syscalls-ABI *******/ + +#define __ARCH_WANT_SYS_EXECVE +#define __ARCH_WANT_SYS_CLONE +#define __ARCH_WANT_SYS_VFORK +#define __ARCH_WANT_SYS_FORK + +#define sys_mmap2 sys_mmap_pgoff + +#include + +#define NR_syscalls __NR_syscalls + +/* ARC specific syscall */ +#define __NR_cacheflush (__NR_arch_specific_syscall + 0) +#define __NR_arc_settls (__NR_arch_specific_syscall + 1) +#define __NR_arc_gettls (__NR_arch_specific_syscall + 2) + +__SYSCALL(__NR_cacheflush, sys_cacheflush) +__SYSCALL(__NR_arc_settls, sys_arc_settls) +__SYSCALL(__NR_arc_gettls, sys_arc_gettls) + + +/* Generic syscall (fs/filesystems.c - lost in asm-generic/unistd.h */ +#define __NR_sysfs (__NR_arch_specific_syscall + 3) +__SYSCALL(__NR_sysfs, sys_sysfs) diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S index a4acc9ee1311..0b0a190547a9 100644 --- a/arch/arc/kernel/entry.S +++ b/arch/arc/kernel/entry.S @@ -569,3 +569,30 @@ ARC_ENTRY ret_from_fork bl @schedule_tail b @ret_from_exception ARC_EXIT ret_from_fork + +;################### Special Sys Call Wrappers ########################## + +; TBD: call do_fork directly from here +ARC_ENTRY sys_fork_wrapper + SAVE_CALLEE_SAVED_USER + bl @sys_fork + DISCARD_CALLEE_SAVED_USER + + b ret_from_system_call +ARC_EXIT sys_fork_wrapper + +ARC_ENTRY sys_vfork_wrapper + SAVE_CALLEE_SAVED_USER + bl @sys_vfork + DISCARD_CALLEE_SAVED_USER + + b ret_from_system_call +ARC_EXIT sys_vfork_wrapper + +ARC_ENTRY sys_clone_wrapper + SAVE_CALLEE_SAVED_USER + bl @sys_clone + DISCARD_CALLEE_SAVED_USER + + b ret_from_system_call +ARC_EXIT sys_clone_wrapper diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c new file mode 100644 index 000000000000..4d14e5638c8c --- /dev/null +++ b/arch/arc/kernel/process.c @@ -0,0 +1,42 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Amit Bhor, Kanika Nema: Codito Technologies 2004 + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +SYSCALL_DEFINE1(arc_settls, void *, user_tls_data_ptr) +{ + task_thread_info(current)->thr_ptr = (unsigned int)user_tls_data_ptr; + return 0; +} + +/* + * We return the user space TLS data ptr as sys-call return code + * Ideally it should be copy to user. + * However we can cheat by the fact that some sys-calls do return + * absurdly high values + * Since the tls dat aptr is not going to be in range of 0xFFFF_xxxx + * it won't be considered a sys-call error + * and it will be loads better than copy-to-user, which is a definite + * D-TLB Miss + */ +SYSCALL_DEFINE0(arc_gettls) +{ + return task_thread_info(current)->thr_ptr; +} diff --git a/arch/arc/kernel/sys.c b/arch/arc/kernel/sys.c new file mode 100644 index 000000000000..f6bdd07583f3 --- /dev/null +++ b/arch/arc/kernel/sys.c @@ -0,0 +1,18 @@ + +#include +#include +#include + +#include + +#define sys_clone sys_clone_wrapper +#define sys_fork sys_fork_wrapper +#define sys_vfork sys_vfork_wrapper + +#undef __SYSCALL +#define __SYSCALL(nr, call) [nr] = (call), + +void *sys_call_table[NR_syscalls] = { + [0 ... NR_syscalls-1] = sys_ni_syscall, +#include +};