[PATCH 1/2] mm: Introducing arch_remap hook
From: Laurent Dufour <hidden>
Date: 2015-03-20 15:54:20
Also in:
linux-arch, linux-mm, linux-s390, linux-um, lkml
Subsystem:
generic include/asm header files, memory management, memory mapping, s390 architecture, the rest, user-mode linux (uml), x86 architecture (32-bit and 64-bit) · Maintainers:
Arnd Bergmann, Andrew Morton, Liam R. Howlett, Lorenzo Stoakes, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Linus Torvalds, Richard Weinberger, Anton Ivanov, Johannes Berg, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Some architecture would like to be triggered when a memory area is moved through the mremap system call. This patch is introducing a new arch_remap mm hook which is placed in the path of mremap, and is called before the old area is unmapped (and the arch_unmap hook is called). To no break the build, this patch adds the empty hook definition to the architectures that were not using the generic hook's definition. Signed-off-by: Laurent Dufour <redacted> --- arch/s390/include/asm/mmu_context.h | 6 ++++++ arch/um/include/asm/mmu_context.h | 5 +++++ arch/unicore32/include/asm/mmu_context.h | 6 ++++++ arch/x86/include/asm/mmu_context.h | 6 ++++++ include/asm-generic/mm_hooks.h | 6 ++++++ mm/mremap.c | 9 +++++++-- 6 files changed, 36 insertions(+), 2 deletions(-)
diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h
index 8fb3802f8fad..ddd861a490ba 100644
--- a/arch/s390/include/asm/mmu_context.h
+++ b/arch/s390/include/asm/mmu_context.h@@ -131,4 +131,10 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm, { } +static inline void arch_remap(struct mm_struct *mm, + unsigned long old_start, unsigned long old_end, + unsigned long new_start, unsigned long new_end) +{ +} + #endif /* __S390_MMU_CONTEXT_H */
diff --git a/arch/um/include/asm/mmu_context.h b/arch/um/include/asm/mmu_context.h
index 941527e507f7..f499b017c1f9 100644
--- a/arch/um/include/asm/mmu_context.h
+++ b/arch/um/include/asm/mmu_context.h@@ -27,6 +27,11 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm, struct vm_area_struct *vma) { } +static inline void arch_remap(struct mm_struct *mm, + unsigned long old_start, unsigned long old_end, + unsigned long new_start, unsigned long new_end) +{ +} /* * end asm-generic/mm_hooks.h functions */
diff --git a/arch/unicore32/include/asm/mmu_context.h b/arch/unicore32/include/asm/mmu_context.h
index 1cb5220afaf9..39a0a553172e 100644
--- a/arch/unicore32/include/asm/mmu_context.h
+++ b/arch/unicore32/include/asm/mmu_context.h@@ -97,4 +97,10 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm, { } +static inline void arch_remap(struct mm_struct *mm, + unsigned long old_start, unsigned long old_end, + unsigned long new_start, unsigned long new_end) +{ +} + #endif
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 883f6b933fa4..75cb71f4be1e 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h@@ -172,4 +172,10 @@ static inline void arch_unmap(struct mm_struct *mm, struct vm_area_struct *vma, mpx_notify_unmap(mm, vma, start, end); } +static inline void arch_remap(struct mm_struct *mm, + unsigned long old_start, unsigned long old_end, + unsigned long new_start, unsigned long new_end) +{ +} + #endif /* _ASM_X86_MMU_CONTEXT_H */
diff --git a/include/asm-generic/mm_hooks.h b/include/asm-generic/mm_hooks.h
index 866aa461efa5..e507f4783a5b 100644
--- a/include/asm-generic/mm_hooks.h
+++ b/include/asm-generic/mm_hooks.h@@ -26,4 +26,10 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm, { } +static inline void arch_remap(struct mm_struct *mm, + unsigned long old_start, unsigned long old_end, + unsigned long new_start, unsigned long new_end) +{ +} + #endif /* _ASM_GENERIC_MM_HOOKS_H */
diff --git a/mm/mremap.c b/mm/mremap.c
index 57dadc025c64..6a409ca09425 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c@@ -25,6 +25,7 @@ #include <asm/cacheflush.h> #include <asm/tlbflush.h> +#include <asm/mmu_context.h> #include "internal.h"
@@ -286,8 +287,12 @@ static unsigned long move_vma(struct vm_area_struct *vma, old_len = new_len; old_addr = new_addr; new_addr = -ENOMEM; - } else if (vma->vm_file && vma->vm_file->f_op->mremap) - vma->vm_file->f_op->mremap(vma->vm_file, new_vma); + } else { + if (vma->vm_file && vma->vm_file->f_op->mremap) + vma->vm_file->f_op->mremap(vma->vm_file, new_vma); + arch_remap(mm, old_addr, old_addr+old_len, + new_addr, new_addr+new_len); + } /* Conceal VM_ACCOUNT so old reservation is not undone */ if (vm_flags & VM_ACCOUNT) {
--
1.9.1