1 files changed, 174 insertions, 0 deletions

diff --git a/include/asm-i386/thread_info.h b/include/asm-i386/thread_info.h
new file mode 100644
index 000000000000..2cd57271801d
--- /dev/null
+++ b/include/asm-i386/thread_info.h
@@ -0,0 +1,174 @@
+/* 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 */