linux-toradex.git/include/asm-generic/pgtable.h, branch v4.3.2

mm: clarify that the function operates on hugepage pte

2015-06-25T00:49:44+00:00

We have confusing functions to clear pmd, pmd_clear_* and pmd_clear.  Add
_huge_ to pmdp_clear functions so that we are clear that they operate on
hugepage pte.

We don't bother about other functions like pmdp_set_wrprotect,
pmdp_clear_flush_young, because they operate on PTE bits and hence
indicate they are operating on hugepage ptes

Signed-off-by: Aneesh Kumar K.V 
Acked-by: Kirill A. Shutemov 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Andrea Arcangeli 
Cc: Martin Schwidefsky 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

powerpc/mm: use generic version of pmdp_clear_flush()

2015-06-25T00:49:44+00:00

Also move the pmd_trans_huge check to generic code.

Signed-off-by: Aneesh Kumar K.V 
Acked-by: Kirill A. Shutemov 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Andrea Arcangeli 
Cc: Martin Schwidefsky 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/thp: split out pmd collapse flush into separate functions

2015-06-25T00:49:44+00:00

Architectures like ppc64 [1] need to do special things while clearing pmd
before a collapse.  For them this operation is largely different from a
normal hugepage pte clear.  Hence add a separate function to clear pmd
before collapse.  After this patch pmdp_* functions operate only on
hugepage pte, and not on regular pmd_t values pointing to page table.

[1] ppc64 needs to invalidate all the normal page pte mappings we already
have inserted in the hardware hash page table.  But before doing that we
need to make sure there are no parallel hash page table insert going on.
So we need to do a kick_all_cpus_sync() before flushing the older hash
table entries.  By moving this to a separate function we capture these
details and mention how it is different from a hugepage pte clear.

This patch is a cleanup and only does code movement for clarity.  There
should not be any change in functionality.

Signed-off-by: Aneesh Kumar K.V 
Acked-by: Kirill A. Shutemov 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Andrea Arcangeli 
Cc: Martin Schwidefsky 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

x86/mm/pat: Add pgprot_writethrough()

2015-06-07T13:28:58+00:00

Add pgprot_writethrough() for setting page protection flags to
Write-Through mode.

Signed-off-by: Toshi Kani 
Signed-off-by: Borislav Petkov 
Cc: Andrew Morton 
Cc: Andy Lutomirski 
Cc: Elliott@hp.com
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Luis R. Rodriguez 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: arnd@arndb.de
Cc: hch@lst.de
Cc: hmh@hmh.eng.br
Cc: jgross@suse.com
Cc: konrad.wilk@oracle.com
Cc: linux-mm 
Cc: linux-nvdimm@lists.01.org
Cc: stefan.bader@canonical.com
Cc: yigal@plexistor.com
Link: http://lkml.kernel.org/r/1433436928-31903-11-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar

mm: change vunmap to tear down huge KVA mappings

2015-04-14T23:49:04+00:00

Change vunmap_pmd_range() and vunmap_pud_range() to tear down huge KVA
mappings when they are set.  pud_clear_huge() and pmd_clear_huge() return
zero when no-operation is performed, i.e.  huge page mapping was not used.

These changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined
on the architecture.

[akpm@linux-foundation.org: use consistent code layout]
Signed-off-by: Toshi Kani 
Cc: "H. Peter Anvin" 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Arnd Bergmann 
Cc: Dave Hansen 
Cc: Robert Elliott 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: change ioremap to set up huge I/O mappings

2015-04-14T23:49:04+00:00

ioremap_pud_range() and ioremap_pmd_range() are changed to create huge I/O
mappings when their capability is enabled, and a request meets required
conditions -- both virtual & physical addresses are aligned by their huge
page size, and a requested range fufills their huge page size.  When
pud_set_huge() or pmd_set_huge() returns zero, i.e.  no-operation is
performed, the code simply falls back to the next level.

The changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined on
the architecture.

Signed-off-by: Toshi Kani 
Cc: "H. Peter Anvin" 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Arnd Bergmann 
Cc: Dave Hansen 
Cc: Robert Elliott 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: define default PGTABLE_LEVELS to two

2015-04-14T23:49:02+00:00

By this time all architectures which support more than two page table
levels should be covered.  This patch add default definiton of
PGTABLE_LEVELS equal 2.

We also add assert to detect inconsistence between CONFIG_PGTABLE_LEVELS
and __PAGETABLE_PMD_FOLDED/__PAGETABLE_PUD_FOLDED.

Signed-off-by: Kirill A. Shutemov 
Tested-by: Guenter Roeck 
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Cc: Matt Turner 
Cc: "David S. Miller" 
Cc: "H. Peter Anvin" 
Cc: "James E.J. Bottomley" 
Cc: Benjamin Herrenschmidt 
Cc: Catalin Marinas 
Cc: Chris Metcalf 
Cc: David Howells 
Cc: Fenghua Yu 
Cc: Geert Uytterhoeven 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: Ingo Molnar 
Cc: Jeff Dike 
Cc: Kirill A. Shutemov 
Cc: Koichi Yasutake 
Cc: Martin Schwidefsky 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Ralf Baechle 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Will Deacon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: remove remaining references to NUMA hinting bits and helpers

2015-02-13T02:54:08+00:00

This patch removes the NUMA PTE bits and associated helpers.  As a
side-effect it increases the maximum possible swap space on x86-64.

One potential source of problems is races between the marking of PTEs
PROT_NONE, NUMA hinting faults and migration.  It must be guaranteed that
a PTE being protected is not faulted in parallel, seen as a pte_none and
corrupting memory.  The base case is safe but transhuge has problems in
the past due to an different migration mechanism and a dependance on page
lock to serialise migrations and warrants a closer look.

task_work hinting update			parallel fault
------------------------			--------------
change_pmd_range
  change_huge_pmd
    __pmd_trans_huge_lock
      pmdp_get_and_clear
						__handle_mm_fault
						pmd_none
						  do_huge_pmd_anonymous_page
						  read? pmd_lock blocks until hinting complete, fail !pmd_none test
						  write? __do_huge_pmd_anonymous_page acquires pmd_lock, checks pmd_none
      pmd_modify
      set_pmd_at

task_work hinting update			parallel migration
------------------------			------------------
change_pmd_range
  change_huge_pmd
    __pmd_trans_huge_lock
      pmdp_get_and_clear
						__handle_mm_fault
						  do_huge_pmd_numa_page
						    migrate_misplaced_transhuge_page
						    pmd_lock waits for updates to complete, recheck pmd_same
      pmd_modify
      set_pmd_at

Both of those are safe and the case where a transhuge page is inserted
during a protection update is unchanged.  The case where two processes try
migrating at the same time is unchanged by this series so should still be
ok.  I could not find a case where we are accidentally depending on the
PTE not being cleared and flushed.  If one is missed, it'll manifest as
corruption problems that start triggering shortly after this series is
merged and only happen when NUMA balancing is enabled.

Signed-off-by: Mel Gorman 
Tested-by: Sasha Levin 
Cc: Aneesh Kumar K.V 
Cc: Benjamin Herrenschmidt 
Cc: Dave Jones 
Cc: Hugh Dickins 
Cc: Ingo Molnar 
Cc: Kirill Shutemov 
Cc: Linus Torvalds 
Cc: Paul Mackerras 
Cc: Rik van Riel 
Cc: Mark Brown 
Cc: Stephen Rothwell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: add p[te|md] protnone helpers for use by NUMA balancing

2015-02-13T02:54:08+00:00

This is a preparatory patch that introduces protnone helpers for automatic
NUMA balancing.

Signed-off-by: Mel Gorman 
Acked-by: Linus Torvalds 
Acked-by: Aneesh Kumar K.V 
Tested-by: Sasha Levin 
Cc: Benjamin Herrenschmidt 
Cc: Dave Jones 
Cc: Hugh Dickins 
Cc: Ingo Molnar 
Cc: Kirill Shutemov 
Cc: Paul Mackerras 
Cc: Rik van Riel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

asm-generic: drop unused pte_file* helpers

2015-02-10T22:30:31+00:00

All users are gone.

Signed-off-by: Kirill A. Shutemov 
Cc: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds