Commit 4b439e25 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

mm, hugetlbfs: Allow an arch to always use generic versions of get_unmapped_area functions 



Unlike most architectures, powerpc can only define at runtime
if it is going to use the generic arch_get_unmapped_area() or not.

Today, powerpc has a copy of the generic arch_get_unmapped_area()
because when selection HAVE_ARCH_UNMAPPED_AREA the generic
arch_get_unmapped_area() is not available.

Rename it generic_get_unmapped_area() and make it independent of
HAVE_ARCH_UNMAPPED_AREA.

Do the same for arch_get_unmapped_area_topdown() versus
HAVE_ARCH_UNMAPPED_AREA_TOPDOWN.

Do the same for hugetlb_get_unmapped_area() versus
HAVE_ARCH_HUGETLB_UNMAPPED_AREA.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: default avatarNicholas Piggin <npiggin@gmail.com>
Acked-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/77f9d3e592f1c8511df9381aa1c4e754651da4d1.1649523076.git.christophe.leroy@csgroup.eu
parent 723820f3

fs/hugetlbfs/inode.c

+13 −4
Original line number Diff line number Diff line
@@ -195,7 +195,6 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) 
 * Called under mmap_write_lock(mm).

 */



#ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA

static unsigned long

hugetlb_get_unmapped_area_bottomup(struct file *file, unsigned long addr,

		unsigned long len, unsigned long pgoff, unsigned long flags)
@@ -244,9 +243,10 @@ hugetlb_get_unmapped_area_topdown(struct file *file, unsigned long addr, 
	return addr;

}



static unsigned long

hugetlb_get_unmapped_area(struct file *file, unsigned long addr,

		unsigned long len, unsigned long pgoff, unsigned long flags)

unsigned long

generic_hugetlb_get_unmapped_area(struct file *file, unsigned long addr,

				  unsigned long len, unsigned long pgoff,

				  unsigned long flags)

{

	struct mm_struct *mm = current->mm;

	struct vm_area_struct *vma;
@@ -283,6 +283,15 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr, 
	return hugetlb_get_unmapped_area_bottomup(file, addr, len,

			pgoff, flags);

}



#ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA

static unsigned long

hugetlb_get_unmapped_area(struct file *file, unsigned long addr,

			  unsigned long len, unsigned long pgoff,

			  unsigned long flags)

{

	return generic_hugetlb_get_unmapped_area(file, addr, len, pgoff, flags);

}

#endif



static size_t

include/linux/hugetlb.h

+5 −0
Original line number Diff line number Diff line
@@ -519,6 +519,11 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, 
					unsigned long flags);

#endif /* HAVE_ARCH_HUGETLB_UNMAPPED_AREA */



unsigned long

generic_hugetlb_get_unmapped_area(struct file *file, unsigned long addr,

				  unsigned long len, unsigned long pgoff,

				  unsigned long flags);



/*

 * huegtlb page specific state flags.  These flags are located in page.private

 * of the hugetlb head page.  Functions created via the below macros should be

include/linux/sched/mm.h

+9 −0
Original line number Diff line number Diff line
@@ -153,6 +153,15 @@ extern unsigned long 
arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,

			  unsigned long len, unsigned long pgoff,

			  unsigned long flags);



unsigned long

generic_get_unmapped_area(struct file *filp, unsigned long addr,

			  unsigned long len, unsigned long pgoff,

			  unsigned long flags);

unsigned long

generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,

				  unsigned long len, unsigned long pgoff,

				  unsigned long flags);

#else

static inline void arch_pick_mmap_layout(struct mm_struct *mm,

					 struct rlimit *rlim_stack) {}

mm/mmap.c

+24 −7
Original line number Diff line number Diff line
@@ -2128,10 +2128,10 @@ unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info) 
 *

 * This function "knows" that -ENOMEM has the bits set.

 */

#ifndef HAVE_ARCH_UNMAPPED_AREA

unsigned long

arch_get_unmapped_area(struct file *filp, unsigned long addr,

		unsigned long len, unsigned long pgoff, unsigned long flags)

generic_get_unmapped_area(struct file *filp, unsigned long addr,

			  unsigned long len, unsigned long pgoff,

			  unsigned long flags)

{

	struct mm_struct *mm = current->mm;

	struct vm_area_struct *vma, *prev;
@@ -2161,15 +2161,23 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, 
	info.align_offset = 0;

	return vm_unmapped_area(&info);

}



#ifndef HAVE_ARCH_UNMAPPED_AREA

unsigned long

arch_get_unmapped_area(struct file *filp, unsigned long addr,

		       unsigned long len, unsigned long pgoff,

		       unsigned long flags)

{

	return generic_get_unmapped_area(filp, addr, len, pgoff, flags);

}

#endif



/*

 * This mmap-allocator allocates new areas top-down from below the

 * stack's low limit (the base):

 */

#ifndef HAVE_ARCH_UNMAPPED_AREA_TOPDOWN

unsigned long

arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,

generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr,

				  unsigned long len, unsigned long pgoff,

				  unsigned long flags)

{
@@ -2219,6 +2227,15 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 


	return addr;

}



#ifndef HAVE_ARCH_UNMAPPED_AREA_TOPDOWN

unsigned long

arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,

			       unsigned long len, unsigned long pgoff,

			       unsigned long flags)

{

	return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);

}

#endif



unsigned long