Commit 40b88644 authored by Michael Ellerman's avatar Michael Ellerman Committed by Andrew Morton
Browse files

mm: remove arch_unmap() 

Now that powerpc no longer uses arch_unmap() to handle VDSO unmapping,
there are no meaningful implementions left.  Drop support for it entirely,
and update comments which refer to it.

Link: https://lkml.kernel.org/r/20240812082605.743814-3-mpe@ellerman.id.au


Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Suggested-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Jeff Xu <jeffxu@google.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 5463bafa

arch/powerpc/include/asm/mmu_context.h

+0 −5
Original line number Diff line number Diff line
@@ -260,11 +260,6 @@ static inline void enter_lazy_tlb(struct mm_struct *mm, 


extern void arch_exit_mmap(struct mm_struct *mm);



static inline void arch_unmap(struct mm_struct *mm,

			      unsigned long start, unsigned long end)

{

}



#ifdef CONFIG_PPC_MEM_KEYS

bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,

			       bool execute, bool foreign);

arch/x86/include/asm/mmu_context.h

+0 −5
Original line number Diff line number Diff line
@@ -232,11 +232,6 @@ static inline bool is_64bit_mm(struct mm_struct *mm) 
}

#endif



static inline void arch_unmap(struct mm_struct *mm, unsigned long start,

			      unsigned long end)

{

}



/*

 * We only want to enforce protection keys on the current process

 * because we effectively have no access to PKRU for other

include/asm-generic/mm_hooks.h

+3 −8
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

/*

 * Define generic no-op hooks for arch_dup_mmap, arch_exit_mmap

 * and arch_unmap to be included in asm-FOO/mmu_context.h for any

 * arch FOO which doesn't need to hook these.

 * Define generic no-op hooks for arch_dup_mmap and arch_exit_mmap

 * to be included in asm-FOO/mmu_context.h for any arch FOO which

 * doesn't need to hook these.

 */

#ifndef _ASM_GENERIC_MM_HOOKS_H

#define _ASM_GENERIC_MM_HOOKS_H
@@ -17,11 +17,6 @@ static inline void arch_exit_mmap(struct mm_struct *mm) 
{

}



static inline void arch_unmap(struct mm_struct *mm,

			unsigned long start, unsigned long end)

{

}



static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,

		bool write, bool execute, bool foreign)

{

mm/mmap.c

+1 −3
Original line number Diff line number Diff line
@@ -1743,14 +1743,12 @@ int do_vma_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, 
	struct mm_struct *mm = vma->vm_mm;



	/*

	 * Check if memory is sealed before arch_unmap.

	 * Prevent unmapping a sealed VMA.

	 * Check if memory is sealed, prevent unmapping a sealed VMA.

	 * can_modify_mm assumes we have acquired the lock on MM.

	 */

	if (unlikely(!can_modify_mm(mm, start, end)))

		return -EPERM;



	arch_unmap(mm, start, end);

	return do_vmi_align_munmap(vmi, vma, mm, start, end, uf, unlock);

}

mm/vma.c

+2 −6
Original line number Diff line number Diff line
@@ -841,7 +841,7 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, 
 *

 * This function takes a @mas that is either pointing to the previous VMA or set

 * to MA_START and sets it up to remove the mapping(s).  The @len will be

 * aligned and any arch_unmap work will be preformed.

 * aligned.

 *

 * Return: 0 on success and drops the lock if so directed, error and leaves the

 * lock held otherwise.
@@ -861,16 +861,12 @@ int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm, 
		return -EINVAL;



	/*

	 * Check if memory is sealed before arch_unmap.

	 * Prevent unmapping a sealed VMA.

	 * Check if memory is sealed, prevent unmapping a sealed VMA.

	 * can_modify_mm assumes we have acquired the lock on MM.

	 */

	if (unlikely(!can_modify_mm(mm, start, end)))

		return -EPERM;



	 /* arch_unmap() might do unmaps itself.  */

	arch_unmap(mm, start, end);



	/* Find the first overlapping VMA */

	vma = vma_find(vmi, end);

	if (!vma) {