> Some very pedantic nitpicking below;
>
> On 22/01/2008, Anton Salikhmetov <salikhmetov@gmail.com> wrote:
> >
http://bugzilla.kernel.org/show_bug.cgi?id=2645#c40
> >
> > Update file times at write references to memory-mapped files.
> > Force file times update at the next write reference after
> > calling the msync() system call with the MS_ASYNC flag.
> >
> > Signed-off-by: Anton Salikhmetov <salikhmetov@gmail.com>
> > ---
> > mm/memory.c | 6 ++++++
> > mm/msync.c | 57 ++++++++++++++++++++++++++++++++++++++++++++-------------
> > 2 files changed, 50 insertions(+), 13 deletions(-)
> >
> > diff --git a/mm/memory.c b/mm/memory.c
> > index 6dd1cd8..4b0144b 100644
> > --- a/mm/memory.c
> > +++ b/mm/memory.c
> > @@ -1670,6 +1670,9 @@ gotten:
> > unlock:
> > pte_unmap_unlock(page_table, ptl);
> > if (dirty_page) {
> > + if (vma->vm_file)
> > + file_update_time(vma->vm_file);
> > +
> > /*
> > * Yes, Virginia, this is actually required to prevent a race
> > * with clear_page_dirty_for_io() from clearing the page dirty
> > @@ -2343,6 +2346,9 @@ out_unlocked:
> > if (anon)
> > page_cache_release(vmf.page);
> > else if (dirty_page) {
> > + if (vma->vm_file)
> > + file_update_time(vma->vm_file);
> > +
> > set_page_dirty_balance(dirty_page, page_mkwrite);
> > put_page(dirty_page);
> > }
> > diff --git a/mm/msync.c b/mm/msync.c
> > index a4de868..394130d 100644
> > --- a/mm/msync.c
> > +++ b/mm/msync.c
> > @@ -5,6 +5,7 @@
> > * Copyright (C) 2008 Anton Salikhmetov <salikhmetov@gmail.com>
> > */
> >
> > +#include <asm/tlbflush.h>
> > #include <linux/file.h>
> > #include <linux/fs.h>
> > #include <linux/mm.h>
> > @@ -13,11 +14,37 @@
> > #include <linux/syscalls.h>
> >
> > /*
> > + * Scan the PTEs for pages belonging to the VMA and mark them read-only.
> > + * It will force a pagefault on the next write access.
> > + */
> > +static void vma_wrprotect(struct vm_area_struct *vma)
> > +{
> > + unsigned long addr;
> > +
> > + for (addr = vma->vm_start; addr < vma->vm_end; addr += PAGE_SIZE) {
>
> I know it's not the common "Linux Kernel way", but 'addr' could be
> made to have just 'for' scope here according to C99;
