parisc: add flexible mmap memory layout support
Add support for the flexible mmap memory layout (as described in
http://lwn.net/Articles/91829). This is especially very interesting on
parisc since we currently only support 32bit userspace (even with a
64bit Linux kernel).
Signed-off-by: Helge Deller <deller@gmx.de>
diff --git a/arch/parisc/include/asm/elf.h b/arch/parisc/include/asm/elf.h
index ad2b503..3391d06 100644
--- a/arch/parisc/include/asm/elf.h
+++ b/arch/parisc/include/asm/elf.h
@@ -348,4 +348,8 @@
#define ELF_HWCAP 0
+struct mm_struct;
+extern unsigned long arch_randomize_brk(struct mm_struct *);
+#define arch_randomize_brk arch_randomize_brk
+
#endif
diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h
index 34899b5..22b89d1 100644
--- a/arch/parisc/include/asm/pgtable.h
+++ b/arch/parisc/include/asm/pgtable.h
@@ -511,6 +511,7 @@
/* We provide our own get_unmapped_area to provide cache coherency */
#define HAVE_ARCH_UNMAPPED_AREA
+#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
diff --git a/arch/parisc/include/asm/processor.h b/arch/parisc/include/asm/processor.h
index cc2290a..198a86f 100644
--- a/arch/parisc/include/asm/processor.h
+++ b/arch/parisc/include/asm/processor.h
@@ -30,6 +30,8 @@
#endif
#define current_text_addr() ({ void *pc; current_ia(pc); pc; })
+#define HAVE_ARCH_PICK_MMAP_LAYOUT
+
#define TASK_SIZE_OF(tsk) ((tsk)->thread.task_size)
#define TASK_SIZE TASK_SIZE_OF(current)
#define TASK_UNMAPPED_BASE (current->thread.map_base)
diff --git a/arch/parisc/include/asm/thread_info.h b/arch/parisc/include/asm/thread_info.h
index d5f97ea..4b9b10c 100644
--- a/arch/parisc/include/asm/thread_info.h
+++ b/arch/parisc/include/asm/thread_info.h
@@ -76,6 +76,16 @@
#define _TIF_SYSCALL_TRACE_MASK (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
_TIF_BLOCKSTEP | _TIF_SYSCALL_AUDIT)
+#ifdef CONFIG_64BIT
+# ifdef CONFIG_COMPAT
+# define is_32bit_task() (test_thread_flag(TIF_32BIT))
+# else
+# define is_32bit_task() (0)
+# endif
+#else
+# define is_32bit_task() (1)
+#endif
+
#endif /* __KERNEL__ */
#endif /* _ASM_PARISC_THREAD_INFO_H */