The patch titled
nommu: don't need get_unmapped_area() for NOMMU
has been added to the -mm tree. Its filename is
nommu-dont-need-get_unmapped_area-for-nommu.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: nommu: don't need get_unmapped_area() for NOMMU
From: David Howells <dhowells@xxxxxxxxxx>
get_unmapped_area() is unnecessary for NOMMU as no-one calls it.
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Acked-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Greg Ungerer <gerg@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mm_types.h | 2 ++
include/linux/sched.h | 7 +++++--
mm/nommu.c | 21 ---------------------
mm/util.c | 2 +-
4 files changed, 8 insertions(+), 24 deletions(-)
diff -puN include/linux/mm_types.h~nommu-dont-need-get_unmapped_area-for-nommu include/linux/mm_types.h
--- a/include/linux/mm_types.h~nommu-dont-need-get_unmapped_area-for-nommu
+++ a/include/linux/mm_types.h
@@ -205,10 +205,12 @@ struct mm_struct {
struct vm_area_struct * mmap; /* list of VMAs */
struct rb_root mm_rb;
struct vm_area_struct * mmap_cache; /* last find_vma result */
+#ifdef CONFIG_MMU
unsigned long (*get_unmapped_area) (struct file *filp,
unsigned long addr, unsigned long len,
unsigned long pgoff, unsigned long flags);
void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
+#endif
unsigned long mmap_base; /* base of mmap area */
unsigned long task_size; /* size of task vm space */
unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
diff -puN include/linux/sched.h~nommu-dont-need-get_unmapped_area-for-nommu include/linux/sched.h
--- a/include/linux/sched.h~nommu-dont-need-get_unmapped_area-for-nommu
+++ a/include/linux/sched.h
@@ -381,6 +381,8 @@ extern int sysctl_max_map_count;
#include <linux/aio.h>
+#ifdef CONFIG_MMU
+extern void arch_pick_mmap_layout(struct mm_struct *mm);
extern unsigned long
arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
unsigned long, unsigned long);
@@ -390,6 +392,9 @@ arch_get_unmapped_area_topdown(struct fi
unsigned long flags);
extern void arch_unmap_area(struct mm_struct *, unsigned long);
extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
+#else
+static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
+#endif
#if USE_SPLIT_PTLOCKS
/*
@@ -2495,8 +2500,6 @@ static inline void set_task_cpu(struct t
#endif /* CONFIG_SMP */
-extern void arch_pick_mmap_layout(struct mm_struct *mm);
-
#ifdef CONFIG_TRACING
extern void
__trace_special(void *__tr, void *__data,
diff -puN mm/nommu.c~nommu-dont-need-get_unmapped_area-for-nommu mm/nommu.c
--- a/mm/nommu.c~nommu-dont-need-get_unmapped_area-for-nommu
+++ a/mm/nommu.c
@@ -1761,27 +1761,6 @@ void unmap_mapping_range(struct address_
EXPORT_SYMBOL(unmap_mapping_range);
/*
- * ask for an unmapped area at which to create a mapping on a file
- */
-unsigned long get_unmapped_area(struct file *file, unsigned long addr,
- unsigned long len, unsigned long pgoff,
- unsigned long flags)
-{
- unsigned long (*get_area)(struct file *, unsigned long, unsigned long,
- unsigned long, unsigned long);
-
- get_area = current->mm->get_unmapped_area;
- if (file && file->f_op && file->f_op->get_unmapped_area)
- get_area = file->f_op->get_unmapped_area;
-
- if (!get_area)
- return -ENOSYS;
-
- return get_area(file, addr, len, pgoff, flags);
-}
-EXPORT_SYMBOL(get_unmapped_area);
-
-/*
* Check that a process has enough memory to allocate a new virtual
* mapping. 0 means there is enough memory for the allocation to
* succeed and -ENOMEM implies there is not.
diff -puN mm/util.c~nommu-dont-need-get_unmapped_area-for-nommu mm/util.c
--- a/mm/util.c~nommu-dont-need-get_unmapped_area-for-nommu
+++ a/mm/util.c
@@ -220,7 +220,7 @@ char *strndup_user(const char __user *s,
}
EXPORT_SYMBOL(strndup_user);
-#ifndef HAVE_ARCH_PICK_MMAP_LAYOUT
+#if defined(CONFIG_MMU) && !defined(HAVE_ARCH_PICK_MMAP_LAYOUT)
void arch_pick_mmap_layout(struct mm_struct *mm)
{
mm->mmap_base = TASK_UNMAPPED_BASE;
_
Patches currently in -mm which might be from dhowells@xxxxxxxxxx are
nommu-fix-sysv-shm-for-nommu.patch
nommu-struct-vm_regions-vm_usage-count-need-not-be-atomic.patch
nommu-remove-a-superfluous-check-of-vm_region-vm_usage.patch
nommu-dont-need-get_unmapped_area-for-nommu.patch
nommu-fix-race-between-ramfs-truncation-and-shared-mmap.patch
nommu-fix-shared-mmap-after-truncate-shrinkage-problems.patch
kernel-credc-use-kmem_cache_free.patch
nfs-avoid-warnings-when-config_nfs_v4=n.patch
frv-duplicate-output_buffer-of-e03.patch
coredump-unify-dump_seek-implementations-for-each-binfmt_c.patch
coredump-move-dump_write-and-dump_seek-into-a-header-file.patch
elf-coredump-replace-elf_core_extra_-macros-by-functions.patch
elf-coredump-make-offset-calculation-process-and-writing-process-explicit.patch
elf-coredump-add-extended-numbering-support.patch
mutex-subsystem-synchro-test-module.patch
mutex-subsystem-synchro-test-module-add-missing-header-file.patch
--
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