maps4: rework TASK_SIZE macros

The following replaces the earlier patches sent.  It should address
David Rientjes's comments, and has been compile tested on all the
architectures that it touches, save for parisc.

For the /proc/<pid>/pagemap code[1], we need to able to query how
much virtual address space a particular task has.  The trick is
that we do it through /proc and can't use TASK_SIZE since it
references "current" on some arches.  The process opening the
/proc file might be a 32-bit process opening a 64-bit process's
pagemap file.

x86_64 already has a TASK_SIZE_OF() macro:

#define TASK_SIZE_OF(child)     ((test_tsk_thread_flag(child, TIF_IA32)) ? IA32_PAGE_OFFSET : TASK_SIZE64)

I'd like to have that for other architectures.  So, add it
for all the architectures that actually use "current" in
their TASK_SIZE.  For the others, just add a quick #define
in sched.h to use plain old TASK_SIZE.

1. http://www.linuxworld.com/news/2007/042407-kernel.html

- MIPS portion from Ralf Baechle <ralf@linux-mips.org>

[akpm@linux-foundation.org: fix mips build]
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/asm-ia64/processor.h b/include/asm-ia64/processor.h
index be3b0ae43270f81800945752f65843b849ef2460..666385b6882040ae586bb80ea7a506260800c97d 100644 (file)
--- a/include/asm-ia64/processor.h
+++ b/include/asm-ia64/processor.h
@@ -31,7 +31,8 @@
  * each (assuming 8KB page size), for a total of 8TB of user virtual
  * address space.
  */
-#define TASK_SIZE              (current->thread.task_size)
+#define TASK_SIZE_OF(tsk)      ((tsk)->thread.task_size)
+#define TASK_SIZE              TASK_SIZE_OF(current)
 
 /*
  * This decides where the kernel will search for a free chunk of vm

diff --git a/include/asm-mips/processor.h b/include/asm-mips/processor.h
index 83bc94534084a429735e9d6620fdb1a02c2d9f80..36f42de594094b73f5b60ffc2dc0f09ebdf20b1c 100644 (file)
--- a/include/asm-mips/processor.h
+++ b/include/asm-mips/processor.h
@@ -65,6 +65,8 @@ extern unsigned int vced_count, vcei_count;
 #define TASK_UNMAPPED_BASE                                             \
        (test_thread_flag(TIF_32BIT_ADDR) ?                             \
                PAGE_ALIGN(TASK_SIZE32 / 3) : PAGE_ALIGN(TASK_SIZE / 3))
+#define TASK_SIZE_OF(tsk)                                              \
+       (test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE)
 #endif
 
 #define NUM_FPU_REGS   32

diff --git a/include/asm-parisc/processor.h b/include/asm-parisc/processor.h
index 6b294fb07a23d6aa9018599f46c80731abb4bb58..3bb06e898fdef5f0ad27d66a7144ed2e945c6d06 100644 (file)
--- a/include/asm-parisc/processor.h
+++ b/include/asm-parisc/processor.h
@@ -32,7 +32,8 @@
 #endif
 #define current_text_addr() ({ void *pc; current_ia(pc); pc; })
 
-#define TASK_SIZE               (current->thread.task_size)
+#define TASK_SIZE_OF(tsk)       ((tsk)->thread.task_size)
+#define TASK_SIZE              TASK_SIZE_OF(current)
 #define TASK_UNMAPPED_BASE      (current->thread.map_base)
 
 #define DEFAULT_TASK_SIZE32    (0xFFF00000UL)

diff --git a/include/asm-powerpc/processor.h b/include/asm-powerpc/processor.h
index dba7c948189db065a0862bcfa8c438f236a15ada..1f4765d6546fe0313b6bbc150ff38b509d6811ba 100644 (file)
--- a/include/asm-powerpc/processor.h
+++ b/include/asm-powerpc/processor.h
@@ -99,8 +99,9 @@ extern struct task_struct *last_task_used_spe;
  */
 #define TASK_SIZE_USER32 (0x0000000100000000UL - (1*PAGE_SIZE))
 
-#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
+#define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
                TASK_SIZE_USER32 : TASK_SIZE_USER64)
+#define TASK_SIZE        TASK_SIZE_OF(current)
 
 /* This decides where the kernel will search for a free chunk of vm
  * space during mmap's.

diff --git a/include/asm-s390/processor.h b/include/asm-s390/processor.h
index c86b982aef5a6bb9ebce57a008617443555084f8..4f744609cd11b35aed60e95e33125553809b1692 100644 (file)
--- a/include/asm-s390/processor.h
+++ b/include/asm-s390/processor.h
@@ -70,8 +70,9 @@ extern int get_cpu_capability(unsigned int *);
 
 #else /* __s390x__ */
 
-# define TASK_SIZE             (test_thread_flag(TIF_31BIT) ? \
+# define TASK_SIZE_OF(tsk)     (test_tsk_thread_flag(tsk, TIF_31BIT) ? \
                                        (0x80000000UL) : (0x40000000000UL))
+# define TASK_SIZE             TASK_SIZE_OF(current)
 # define TASK_UNMAPPED_BASE    (TASK_SIZE / 2)
 # define DEFAULT_TASK_SIZE     (0x40000000000UL)
 

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 483ea4e1accf3f4ffba55c76c225966491b5db53..c30d174a02fa5b6b8343c4f058f9edf7ff0312f9 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2087,6 +2087,10 @@ static inline void migration_init(void)
 }
 #endif
 
+#ifndef TASK_SIZE_OF
+#define TASK_SIZE_OF(tsk)      TASK_SIZE
+#endif
+
 #endif /* __KERNEL__ */
 
 #endif