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-rw-r--r--include/asm-i386/thread_info.h174
1 files changed, 174 insertions, 0 deletions
diff --git a/include/asm-i386/thread_info.h b/include/asm-i386/thread_info.h
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+++ b/include/asm-i386/thread_info.h
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+/* thread_info.h: i386 low-level thread information
+ *
+ * Copyright (C) 2002 David Howells (dhowells@redhat.com)
+ * - Incorporating suggestions made by Linus Torvalds and Dave Miller
+ */
+
+#ifndef _ASM_THREAD_INFO_H
+#define _ASM_THREAD_INFO_H
+
+#ifdef __KERNEL__
+
+#include <linux/config.h>
+#include <linux/compiler.h>
+#include <asm/page.h>
+
+#ifndef __ASSEMBLY__
+#include <asm/processor.h>
+#endif
+
+/*
+ * 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
+ */
+#ifndef __ASSEMBLY__
+
+struct thread_info {
+ struct task_struct *task; /* main task structure */
+ struct exec_domain *exec_domain; /* execution domain */
+ unsigned long flags; /* low level flags */
+ unsigned long status; /* thread-synchronous flags */
+ __u32 cpu; /* current CPU */
+ __s32 preempt_count; /* 0 => preemptable, <0 => BUG */
+
+
+ mm_segment_t addr_limit; /* thread address space:
+ 0-0xBFFFFFFF for user-thead
+ 0-0xFFFFFFFF for kernel-thread
+ */
+ struct restart_block restart_block;
+
+ unsigned long previous_esp; /* ESP of the previous stack in case
+ of nested (IRQ) stacks
+ */
+ __u8 supervisor_stack[0];
+};
+
+#else /* !__ASSEMBLY__ */
+
+#include <asm/asm_offsets.h>
+
+#endif
+
+#define PREEMPT_ACTIVE 0x10000000
+#ifdef CONFIG_4KSTACKS
+#define THREAD_SIZE (4096)
+#else
+#define THREAD_SIZE (8192)
+#endif
+
+#define STACK_WARN (THREAD_SIZE/8)
+/*
+ * macros/functions for gaining access to the thread information structure
+ *
+ * preempt_count needs to be 1 initially, until the scheduler is functional.
+ */
+#ifndef __ASSEMBLY__
+
+#define INIT_THREAD_INFO(tsk) \
+{ \
+ .task = &tsk, \
+ .exec_domain = &default_exec_domain, \
+ .flags = 0, \
+ .cpu = 0, \
+ .preempt_count = 1, \
+ .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)
+
+
+/* how to get the thread information struct from C */
+static inline struct thread_info *current_thread_info(void)
+{
+ struct thread_info *ti;
+ __asm__("andl %%esp,%0; ":"=r" (ti) : "0" (~(THREAD_SIZE - 1)));
+ return ti;
+}
+
+/* how to get the current stack pointer from C */
+register unsigned long current_stack_pointer asm("esp") __attribute_used__;
+
+/* thread information allocation */
+#ifdef CONFIG_DEBUG_STACK_USAGE
+#define alloc_thread_info(tsk) \
+ ({ \
+ struct thread_info *ret; \
+ \
+ ret = kmalloc(THREAD_SIZE, GFP_KERNEL); \
+ if (ret) \
+ memset(ret, 0, THREAD_SIZE); \
+ ret; \
+ })
+#else
+#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
+#endif
+
+#define free_thread_info(info) kfree(info)
+#define get_thread_info(ti) get_task_struct((ti)->task)
+#define put_thread_info(ti) put_task_struct((ti)->task)
+
+#else /* !__ASSEMBLY__ */
+
+/* how to get the thread information struct from ASM */
+#define GET_THREAD_INFO(reg) \
+ movl $-THREAD_SIZE, reg; \
+ andl %esp, reg
+
+/* use this one if reg already contains %esp */
+#define GET_THREAD_INFO_WITH_ESP(reg) \
+ andl $-THREAD_SIZE, reg
+
+#endif
+
+/*
+ * 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_SYSCALL_TRACE 0 /* syscall trace active */
+#define TIF_NOTIFY_RESUME 1 /* resumption notification requested */
+#define TIF_SIGPENDING 2 /* signal pending */
+#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
+#define TIF_SINGLESTEP 4 /* restore singlestep on return to user mode */
+#define TIF_IRET 5 /* return with iret */
+#define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
+#define TIF_SECCOMP 8 /* secure computing */
+#define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */
+#define TIF_MEMDIE 17
+
+#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_SINGLESTEP (1<<TIF_SINGLESTEP)
+#define _TIF_IRET (1<<TIF_IRET)
+#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
+#define _TIF_SECCOMP (1<<TIF_SECCOMP)
+#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
+
+/* work to do on interrupt/exception return */
+#define _TIF_WORK_MASK \
+ (0x0000FFFF & ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP|_TIF_SECCOMP))
+/* work to do on any return to u-space */
+#define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
+
+/*
+ * Thread-synchronous status.
+ *
+ * This is different from the flags in that nobody else
+ * ever touches our thread-synchronous status, so we don't
+ * have to worry about atomic accesses.
+ */
+#define TS_USEDFPU 0x0001 /* FPU was used by this task this quantum (SMP) */
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_THREAD_INFO_H */