diff options
author | Vineet Gupta <vgupta@synopsys.com> | 2013-01-18 13:42:17 +0400 |
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committer | Vineet Gupta <vgupta@synopsys.com> | 2013-02-11 18:30:34 +0400 |
commit | 3be80aaef861a60b85a9323462ebb5f623774f7a (patch) | |
tree | b5224ff6c43f4a5787b72a18b83b6d4de7dbddf7 /arch/arc/include/asm/thread_info.h | |
parent | ca15c8ecd588dda4377d18d6d27bc1e87b4177cb (diff) | |
download | linux-3be80aaef861a60b85a9323462ebb5f623774f7a.tar.xz |
ARC: Fundamental ARCH data-types/defines
* L1_CACHE_SHIFT
* PAGE_SIZE, PAGE_OFFSET
* struct pt_regs, struct user_regs_struct
* struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ...
* struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ...
* BUG()
* ELF_*
* Elf_*
To disallow user-space visibility into some of the core kernel data-types
such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header
spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Jonas Bonn <jonas.bonn@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arc/include/asm/thread_info.h')
-rw-r--r-- | arch/arc/include/asm/thread_info.h | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/arch/arc/include/asm/thread_info.h b/arch/arc/include/asm/thread_info.h new file mode 100644 index 000000000000..2d50a4cdd7f3 --- /dev/null +++ b/arch/arc/include/asm/thread_info.h @@ -0,0 +1,121 @@ +/* + * 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. + * + * Vineetg: Oct 2009 + * No need for ARC specific thread_info allocator (kmalloc/free). This is + * anyways one page allocation, thus slab alloc can be short-circuited and + * the generic version (get_free_page) would be loads better. + * + * Sameer Dhavale: Codito Technologies 2004 + */ + +#ifndef _ASM_THREAD_INFO_H +#define _ASM_THREAD_INFO_H + +#ifdef __KERNEL__ + +#include <asm/page.h> + +#ifdef CONFIG_16KSTACKS +#define THREAD_SIZE_ORDER 1 +#else +#define THREAD_SIZE_ORDER 0 +#endif + +#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) + +#ifndef __ASSEMBLY__ + +#include <linux/thread_info.h> +#include <asm/segment.h> + +/* + * low level task data that entry.S needs immediate access to + * - this struct should fit entirely inside of one cache line + * - this struct shares the supervisor stack pages + * - if the contents of this structure are changed, the assembly constants + * must also be changed + */ +struct thread_info { + unsigned long flags; /* low level flags */ + int preempt_count; /* 0 => preemptable, <0 => BUG */ + struct task_struct *task; /* main task structure */ + mm_segment_t addr_limit; /* thread address space */ + struct exec_domain *exec_domain;/* execution domain */ + __u32 cpu; /* current CPU */ + unsigned long thr_ptr; /* TLS ptr */ + struct restart_block restart_block; +}; + +/* + * macros/functions for gaining access to the thread information structure + * + * preempt_count needs to be 1 initially, until the scheduler is functional. + */ +#define INIT_THREAD_INFO(tsk) \ +{ \ + .task = &tsk, \ + .exec_domain = &default_exec_domain, \ + .flags = 0, \ + .cpu = 0, \ + .preempt_count = INIT_PREEMPT_COUNT, \ + .addr_limit = KERNEL_DS, \ + .restart_block = { \ + .fn = do_no_restart_syscall, \ + }, \ +} + +#define init_thread_info (init_thread_union.thread_info) +#define init_stack (init_thread_union.stack) + +static inline __attribute_const__ struct thread_info *current_thread_info(void) +{ + register unsigned long sp asm("sp"); + return (struct thread_info *)(sp & ~(THREAD_SIZE - 1)); +} + +#endif /* !__ASSEMBLY__ */ + +#define PREEMPT_ACTIVE 0x10000000 + +/* + * thread information flags + * - these are process state flags that various assembly files may need to + * access + * - pending work-to-be-done flags are in LSW + * - other flags in MSW + */ +#define TIF_RESTORE_SIGMASK 0 /* restore sig mask in do_signal() */ +#define TIF_NOTIFY_RESUME 1 /* resumption notification requested */ +#define TIF_SIGPENDING 2 /* signal pending */ +#define TIF_NEED_RESCHED 3 /* rescheduling necessary */ +#define TIF_SYSCALL_AUDIT 4 /* syscall auditing active */ +#define TIF_SYSCALL_TRACE 15 /* syscall trace active */ + +/* true if poll_idle() is polling TIF_NEED_RESCHED */ +#define TIF_MEMDIE 16 + +#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) +#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME) +#define _TIF_SIGPENDING (1<<TIF_SIGPENDING) +#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) +#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) +#define _TIF_MEMDIE (1<<TIF_MEMDIE) + +/* work to do on interrupt/exception return */ +#define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ + _TIF_NOTIFY_RESUME) + +/* + * _TIF_ALLWORK_MASK includes SYSCALL_TRACE, but we don't need it. + * SYSCALL_TRACE is anways seperately/unconditionally tested right after a + * syscall, so all that reamins to be tested is _TIF_WORK_MASK + */ + +#endif /* __KERNEL__ */ + +#endif /* _ASM_THREAD_INFO_H */ |