From: Laurent Dufour Date: Wed, 24 Jun 2015 23:56:19 +0000 (-0700) Subject: mm: new arch_remap() hook X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=4abad2ca4a4dbdd4a218c12451231ab628f2e60c;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git mm: new arch_remap() hook Some architectures would like to be triggered when a memory area is moved through the mremap system call. This patch introduces 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). Signed-off-by: Laurent Dufour Cc: "Kirill A. Shutemov" Cc: Hugh Dickins Cc: Rik van Riel Cc: Mel Gorman Cc: Pavel Emelyanov Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/linux/mm-arch-hooks.h b/include/linux/mm-arch-hooks.h index 63005e367abd..4efc3f56e6df 100644 --- a/include/linux/mm-arch-hooks.h +++ b/include/linux/mm-arch-hooks.h @@ -13,4 +13,13 @@ #include +#ifndef arch_remap +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) +{ +} +#define arch_remap arch_remap +#endif + #endif /* _LINUX_MM_ARCH_HOOKS_H */ diff --git a/mm/mremap.c b/mm/mremap.c index 034e2d360652..a7c93eceb1c8 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include @@ -286,13 +287,17 @@ 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) { - err = vma->vm_file->f_op->mremap(vma->vm_file, new_vma); - if (err < 0) { - move_page_tables(new_vma, new_addr, vma, old_addr, - moved_len, true); - return err; + } else { + if (vma->vm_file && vma->vm_file->f_op->mremap) { + err = vma->vm_file->f_op->mremap(vma->vm_file, new_vma); + if (err < 0) { + move_page_tables(new_vma, new_addr, vma, + old_addr, moved_len, true); + return err; + } } + arch_remap(mm, old_addr, old_addr + old_len, + new_addr, new_addr + new_len); } /* Conceal VM_ACCOUNT so old reservation is not undone */