rename thread_info to stack

This finally renames the thread_info field in task structure to stack, so that
the assumptions about this field are gone and archs have more freedom about
placing the thread_info structure.

Nonbroken archs which have a proper thread pointer can do the access to both
current thread and task structure via a single pointer.

It'll allow for a few more cleanups of the fork code, from which e.g.  ia64
could benefit.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
[akpm@linux-foundation.org: build fix]
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Andi Kleen <ak@muc.de>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

7 files changed, 18 insertions, 18 deletions

diff --git a/include/asm-alpha/thread_info.h b/include/asm-alpha/thread_info.h
index eeb3bef91e11..f4defc2bd3fb 100644
--- a/include/asm-alpha/thread_info.h
+++ b/include/asm-alpha/thread_info.h
@@ -97,7 +97,7 @@ register struct thread_info *__current_thread_info __asm__("$8");
                                  1 << TIF_UAC_SIGBUS)
 
 #define SET_UNALIGN_CTL(task,value)     ({                                   \
-        (task)->thread_info->flags = (((task)->thread_info->flags &          \
+        task_thread_info(task)->flags = ((task_thread_info(task)->flags &    \
                 ~ALPHA_UAC_MASK)                                             \
                 | (((value) << ALPHA_UAC_SHIFT)       & (1<<TIF_UAC_NOPRINT))\
                 | (((value) << (ALPHA_UAC_SHIFT + 1)) & (1<<TIF_UAC_SIGBUS)) \
@@ -105,11 +105,11 @@ register struct thread_info *__current_thread_info __asm__("$8");
         0; })
 
 #define GET_UNALIGN_CTL(task,value)     ({                              \
-        put_user(((task)->thread_info->flags & (1 << TIF_UAC_NOPRINT))  \
+        put_user((task_thread_info(task)->flags & (1 << TIF_UAC_NOPRINT))\
                   >> ALPHA_UAC_SHIFT                                    \
-                 | ((task)->thread_info->flags & (1 << TIF_UAC_SIGBUS)) \
+                 | (task_thread_info(task)->flags & (1 << TIF_UAC_SIGBUS))\
                  >> (ALPHA_UAC_SHIFT + 1)                               \
-                 | ((task)->thread_info->flags & (1 << TIF_UAC_NOFIX))  \
+                 | (task_thread_info(task)->flags & (1 << TIF_UAC_NOFIX))\
                  >> (ALPHA_UAC_SHIFT - 1),                              \
                  (int __user *)(value));                                \
         })
diff --git a/include/asm-blackfin/processor.h b/include/asm-blackfin/processor.h
index 997465c93e82..0336ff132c16 100644
--- a/include/asm-blackfin/processor.h
+++ b/include/asm-blackfin/processor.h
@@ -58,10 +58,10 @@ do {									\
         (_regs)->pc = (_pc);                                            \
         if (current->mm)                                                \
                 (_regs)->p5 = current->mm->start_data;                  \
-        current->thread_info->l1_task_info.stack_start                  \
+        task_thread_info(current)->l1_task_info.stack_start             \
                 = (void *)current->mm->context.stack_start;             \
-        current->thread_info->l1_task_info.lowest_sp = (void *)(_usp);          \
-        memcpy(L1_SCRATCH_TASK_INFO, &current->thread_info->l1_task_info,       \
+        task_thread_info(current)->l1_task_info.lowest_sp = (void *)(_usp); \
+        memcpy(L1_SCRATCH_TASK_INFO, &task_thread_info(current)->l1_task_info, \
                 sizeof(*L1_SCRATCH_TASK_INFO));                         \
         wrusp(_usp);                                                    \
 } while(0)
diff --git a/include/asm-blackfin/system.h b/include/asm-blackfin/system.h
index b5bf6e7cb5e8..5e5f1a0566c0 100644
--- a/include/asm-blackfin/system.h
+++ b/include/asm-blackfin/system.h
@@ -239,9 +239,9 @@ asmlinkage struct task_struct *resume(struct task_struct *prev, struct task_stru
 
 #define switch_to(prev,next,last) \
 do {    \
-        memcpy (&prev->thread_info->l1_task_info, L1_SCRATCH_TASK_INFO, \
+        memcpy (&task_thread_info(prev)->l1_task_info, L1_SCRATCH_TASK_INFO, \
                 sizeof *L1_SCRATCH_TASK_INFO); \
-        memcpy (L1_SCRATCH_TASK_INFO, &next->thread_info->l1_task_info, \
+        memcpy (L1_SCRATCH_TASK_INFO, &task_thread_info(next)->l1_task_info, \
                 sizeof *L1_SCRATCH_TASK_INFO); \
         (last) = resume (prev, next);   \
 } while (0)
diff --git a/include/asm-m68k/thread_info.h b/include/asm-m68k/thread_info.h
index c4d622a57dfb..d635a3752488 100644
--- a/include/asm-m68k/thread_info.h
+++ b/include/asm-m68k/thread_info.h
@@ -37,17 +37,17 @@ struct thread_info {
 #define init_stack              (init_thread_union.stack)
 
 #define task_thread_info(tsk)   (&(tsk)->thread.info)
-#define task_stack_page(tsk)    ((void *)(tsk)->thread_info)
+#define task_stack_page(tsk)    ((tsk)->stack)
 #define current_thread_info()   task_thread_info(current)
 
 #define __HAVE_THREAD_FUNCTIONS
 
 #define setup_thread_stack(p, org) ({                   \
-        *(struct task_struct **)(p)->thread_info = (p); \
+        *(struct task_struct **)(p)->stack = (p);       \
         task_thread_info(p)->task = (p);                \
 })
 
-#define end_of_stack(p) ((unsigned long *)(p)->thread_info + 1)
+#define end_of_stack(p) ((unsigned long *)(p)->stack + 1)
 
 /* entry.S relies on these definitions!
  * bits 0-7 are tested at every exception exit
diff --git a/include/asm-x86_64/system.h b/include/asm-x86_64/system.h
index b7b8021e8c43..ead9f9a56234 100644
--- a/include/asm-x86_64/system.h
+++ b/include/asm-x86_64/system.h
@@ -39,7 +39,7 @@
                        [threadrsp] "i" (offsetof(struct task_struct, thread.rsp)), \
                        [ti_flags] "i" (offsetof(struct thread_info, flags)),\
                        [tif_fork] "i" (TIF_FORK),                         \
-                       [thread_info] "i" (offsetof(struct task_struct, thread_info)), \
+                       [thread_info] "i" (offsetof(struct task_struct, stack)), \
                        [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent))   \
                      : "memory", "cc" __EXTRA_CLOBBER)
     
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 795102309bf1..45170b2fa253 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -95,7 +95,7 @@ extern struct group_info init_groups;
 #define INIT_TASK(tsk)  \
 {                                                                       \
         .state          = 0,                                            \
-        .thread_info    = &init_thread_info,                            \
+        .stack          = &init_thread_info,                            \
         .usage          = ATOMIC_INIT(2),                               \
         .flags          = 0,                                            \
         .lock_depth     = -1,                                           \
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 28000b1658f9..17b72d88c4cb 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -817,7 +817,7 @@ struct prio_array;
 
 struct task_struct {
         volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
-        struct thread_info *thread_info;
+        void *stack;
         atomic_t usage;
         unsigned int flags;     /* per process flags, defined below */
         unsigned int ptrace;
@@ -1513,8 +1513,8 @@ static inline void unlock_task_sighand(struct task_struct *tsk,
 
 #ifndef __HAVE_THREAD_FUNCTIONS
 
-#define task_thread_info(task) (task)->thread_info
-#define task_stack_page(task) ((void*)((task)->thread_info))
+#define task_thread_info(task)  ((struct thread_info *)(task)->stack)
+#define task_stack_page(task)   ((task)->stack)
 
 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
 {
@@ -1524,7 +1524,7 @@ static inline void setup_thread_stack(struct task_struct *p, struct task_struct
 
 static inline unsigned long *end_of_stack(struct task_struct *p)
 {
-        return (unsigned long *)(p->thread_info + 1);
+        return (unsigned long *)(task_thread_info(p) + 1);
 }
 
 #endif