linux-toradex.git/include/linux/huge_mm.h, branch v4.4.93

dax: don't use set_huge_zero_page()

2015-09-08T22:35:28+00:00

This is another place where DAX assumed that pgtable_t was a pointer.
Open code the important parts of set_huge_zero_page() in DAX and make
set_huge_zero_page() static again.

Signed-off-by: Kirill A. Shutemov 
Signed-off-by: Matthew Wilcox 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: add vmf_insert_pfn_pmd()

2015-09-08T22:35:28+00:00

Similar to vm_insert_pfn(), but for PMDs rather than PTEs.  The 'vmf_'
prefix instead of 'vm_' prefix is intended to indicate that it returns a
VMF_ value rather than an errno (which would only have to be converted
into a VMF_ value anyway).

Signed-off-by: Matthew Wilcox 
Cc: Hillf Danton 
Cc: "Kirill A. Shutemov" 
Cc: Theodore Ts'o 
Cc: Jan Kara 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: export various functions for the benefit of DAX

2015-09-08T22:35:28+00:00

To use the huge zero page in DAX, we need these functions exported.

Signed-off-by: Matthew Wilcox 
Cc: Hillf Danton 
Cc: "Kirill A. Shutemov" 
Cc: Theodore Ts'o 
Cc: Jan Kara 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

thp: vma_adjust_trans_huge(): adjust file-backed VMA too

2015-09-08T22:35:28+00:00

This series of patches adds support for using PMD page table entries to
map DAX files.  We expect NV-DIMMs to start showing up that are many
gigabytes in size and the memory consumption of 4kB PTEs will be
astronomical.

The patch series leverages much of the Transparant Huge Pages
infrastructure, going so far as to borrow one of Kirill's patches from
his THP page cache series.

This patch (of 10):

Since we're going to have huge pages in page cache, we need to call adjust
file-backed VMA, which potentially can contain huge pages.

For now we call it for all VMAs.

Probably later we will need to introduce a flag to indicate that the VMA
has huge pages.

Signed-off-by: Kirill A. Shutemov 
Signed-off-by: Matthew Wilcox 
Acked-by: Hillf Danton 
Cc: Theodore Ts'o 
Cc: Jan Kara 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm:add KPF_ZERO_PAGE flag for /proc/kpageflags

2015-02-12T01:06:00+00:00

Add KPF_ZERO_PAGE flag for zero_page, so that userspace processes can
detect zero_page in /proc/kpageflags, and then do memory analysis more
accurately.

Signed-off-by: Yalin Wang 
Acked-by: Kirill A. Shutemov 
Cc: Konstantin Khlebnikov 
Cc: Naoya Horiguchi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: convert a few VM_BUG_ON callers to VM_BUG_ON_VMA

2014-10-10T02:25:57+00:00

Trivially convert a few VM_BUG_ON calls to VM_BUG_ON_VMA to extract
more information when they trigger.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Sasha Levin 
Reviewed-by: Naoya Horiguchi 
Cc: Kirill A. Shutemov 
Cc: Konstantin Khlebnikov 
Cc: Rik van Riel 
Cc: Mel Gorman 
Cc: Michal Hocko 
Cc: Hugh Dickins 
Cc: Vlastimil Babka 
Cc: Michel Lespinasse 
Cc: Minchan Kim 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: make copy_pte_range static again

2014-08-07T01:01:19+00:00

Commit 71e3aac0724f ("thp: transparent hugepage core") adds
copy_pte_range prototype to huge_mm.h.  I'm not sure why (or if) this
function have been used outside of memory.c, but it currently isn't.
This patch makes copy_pte_range() static again.

Signed-off-by: Jerome Marchand 
Acked-by: David Rientjes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: close PageTail race

2014-03-04T15:55:47+00:00

Commit bf6bddf1924e ("mm: introduce compaction and migration for
ballooned pages") introduces page_count(page) into memory compaction
which dereferences page->first_page if PageTail(page).

This results in a very rare NULL pointer dereference on the
aforementioned page_count(page).  Indeed, anything that does
compound_head(), including page_count() is susceptible to racing with
prep_compound_page() and seeing a NULL or dangling page->first_page
pointer.

This patch uses Andrea's implementation of compound_trans_head() that
deals with such a race and makes it the default compound_head()
implementation.  This includes a read memory barrier that ensures that
if PageTail(head) is true that we return a head page that is neither
NULL nor dangling.  The patch then adds a store memory barrier to
prep_compound_page() to ensure page->first_page is set.

This is the safest way to ensure we see the head page that we are
expecting, PageTail(page) is already in the unlikely() path and the
memory barriers are unfortunately required.

Hugetlbfs is the exception, we don't enforce a store memory barrier
during init since no race is possible.

Signed-off-by: David Rientjes 
Cc: Holger Kiehl 
Cc: Christoph Lameter 
Cc: Rafael Aquini 
Cc: Vlastimil Babka 
Cc: Michal Hocko 
Cc: Mel Gorman 
Cc: Andrea Arcangeli 
Cc: Rik van Riel 
Cc: "Kirill A. Shutemov" 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: thp: optimize compound_trans_huge

2014-01-22T00:19:43+00:00

Currently we don't clobber page_tail->first_page during split_huge_page,
so compound_trans_head can be set to compound_head without adverse
effects, and this mostly optimizes away a smp_rmb.

It looks worthwhile to keep around the implementation that doesn't relay
on page_tail->first_page not to be clobbered, because it would be
necessary if we'll decide to enforce page->private to zero at all times
whenever PG_private is not set, also for anonymous pages.  For anonymous
pages enforcing such an invariant doesn't matter as anonymous pages
don't use page->private so we can get away with this microoptimization.

Signed-off-by: Andrea Arcangeli 
Cc: Khalid Aziz 
Cc: Pravin Shelar 
Cc: Greg Kroah-Hartman 
Cc: Ben Hutchings 
Cc: Christoph Lameter 
Cc: Johannes Weiner 
Cc: Mel Gorman 
Cc: Rik van Riel 
Cc: Andi Kleen 
Cc: Minchan Kim 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm, thp: move ptl taking inside page_check_address_pmd()

2013-11-15T00:32:14+00:00

With split page table lock we can't know which lock we need to take
before we find the relevant pmd.

Let's move lock taking inside the function.

Signed-off-by: Naoya Horiguchi 
Signed-off-by: Kirill A. Shutemov 
Tested-by: Alex Thorlton 
Cc: Ingo Molnar 
Cc: "Eric W . Biederman" 
Cc: "Paul E . McKenney" 
Cc: Al Viro 
Cc: Andi Kleen 
Cc: Andrea Arcangeli 
Cc: Dave Hansen 
Cc: Dave Jones 
Cc: David Howells 
Cc: Frederic Weisbecker 
Cc: Johannes Weiner 
Cc: Kees Cook 
Cc: Mel Gorman 
Cc: Michael Kerrisk 
Cc: Oleg Nesterov 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Robin Holt 
Cc: Sedat Dilek 
Cc: Srikar Dronamraju 
Cc: Thomas Gleixner 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds