linux-toradex.git/include/linux/mm.h, branch v2.6.36-rc5

mm: Move vma_stack_continue into mm.h

2010-09-09T16:05:06+00:00

So it can be used by all that need to check for that.

Signed-off-by: Stefan Bader 
Signed-off-by: Linus Torvalds

NOMMU: Stub out vm_get_page_prot() if there's no MMU

2010-08-28T21:01:03+00:00

Stub out vm_get_page_prot() if there's no MMU.

This was added by commit 804af2cf6e7a ("[AGPGART] remove private page
protection map") and is used in commit c07fbfd17e61 ("fbmem: VM_IO set,
but not propagated") in the fbmem video driver, but the function doesn't
exist on NOMMU, resulting in an undefined symbol at link time.

Signed-off-by: David Howells 
Reviewed-by: Konrad Rzeszutek Wilk 
Signed-off-by: Linus Torvalds

guard page for stacks that grow upwards

2010-08-24T19:13:20+00:00

pa-risc and ia64 have stacks that grow upwards. Check that
they do not run into other mappings. By making VM_GROWSUP
0x0 on architectures that do not ever use it, we can avoid
some unpleasant #ifdefs in check_stack_guard_page().

Signed-off-by: Tony Luck 
Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2010-08-10T18:26:52+00:00

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (96 commits)
  no need for list_for_each_entry_safe()/resetting with superblock list
  Fix sget() race with failing mount
  vfs: don't hold s_umount over close_bdev_exclusive() call
  sysv: do not mark superblock dirty on remount
  sysv: do not mark superblock dirty on mount
  btrfs: remove junk sb_dirt change
  BFS: clean up the superblock usage
  AFFS: wait for sb synchronization when needed
  AFFS: clean up dirty flag usage
  cifs: truncate fallout
  mbcache: fix shrinker function return value
  mbcache: Remove unused features
  add f_flags to struct statfs(64)
  pass a struct path to vfs_statfs
  update VFS documentation for method changes.
  All filesystems that need invalidate_inode_buffers() are doing that explicitly
  convert remaining ->clear_inode() to ->evict_inode()
  Make ->drop_inode() just return whether inode needs to be dropped
  fs/inode.c:clear_inode() is gone
  fs/inode.c:evict() doesn't care about delete vs. non-delete paths now
  ...

Fix up trivial conflicts in fs/nilfs2/super.c

check ATTR_SIZE contraints in inode_change_ok

2010-08-09T20:47:39+00:00

Make sure we check the truncate constraints early on in ->setattr by adding
those checks to inode_change_ok.  Also clean up and document inode_change_ok
to make this obvious.

As a fallout we don't have to call inode_newsize_ok from simple_setsize and
simplify it down to a truncate_setsize which doesn't return an error.  This
simplifies a lot of setattr implementations and means we use truncate_setsize
almost everywhere.  Get rid of fat_setsize now that it's trivial and mark
ext2_setsize static to make the calling convention obvious.

Keep the inode_newsize_ok in vmtruncate for now as all callers need an
audit for its removal anyway.

Note: setattr code in ecryptfs doesn't call inode_change_ok at all and
needs a deeper audit, but that is left for later.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

KVM: Avoid killing userspace through guest SRAO MCE on unmapped pages

2010-08-01T07:35:26+00:00

In common cases, guest SRAO MCE will cause corresponding poisoned page
be un-mapped and SIGBUS be sent to QEMU-KVM, then QEMU-KVM will relay
the MCE to guest OS.

But it is reported that if the poisoned page is accessed in guest
after unmapping and before MCE is relayed to guest OS, userspace will
be killed.

The reason is as follows. Because poisoned page has been un-mapped,
guest access will cause guest exit and kvm_mmu_page_fault will be
called. kvm_mmu_page_fault can not get the poisoned page for fault
address, so kernel and user space MMIO processing is tried in turn. In
user MMIO processing, poisoned page is accessed again, then userspace
is killed by force_sig_info.

To fix the bug, kvm_mmu_page_fault send HWPOISON signal to QEMU-KVM
and do not try kernel and user space MMIO processing for poisoned
page.

[xiao: fix warning introduced by avi]

Reported-by: Max Asbock 
Signed-off-by: Huang Ying 
Signed-off-by: Xiao Guangrong 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Avi Kivity

mm: add context argument to shrinker callback

2010-07-19T04:56:17+00:00

The current shrinker implementation requires the registered callback
to have global state to work from. This makes it difficult to shrink
caches that are not global (e.g. per-filesystem caches). Pass the shrinker
structure to the callback so that users can embed the shrinker structure
in the context the shrinker needs to operate on and get back to it in the
callback via container_of().

Signed-off-by: Dave Chinner 
Reviewed-by: Christoph Hellwig

mm: make lowmem_page_address() use PFN_PHYS() for improved portability

2010-05-25T15:07:02+00:00

This ensures that platforms with lowmem PAs above 32 bits work correctly
by avoiding truncating the PA during a left shift.

Signed-off-by: Chris Metcalf 
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: compaction: memory compaction core

2010-05-25T15:06:59+00:00

This patch is the core of a mechanism which compacts memory in a zone by
relocating movable pages towards the end of the zone.

A single compaction run involves a migration scanner and a free scanner.
Both scanners operate on pageblock-sized areas in the zone.  The migration
scanner starts at the bottom of the zone and searches for all movable
pages within each area, isolating them onto a private list called
migratelist.  The free scanner starts at the top of the zone and searches
for suitable areas and consumes the free pages within making them
available for the migration scanner.  The pages isolated for migration are
then migrated to the newly isolated free pages.

[aarcange@redhat.com: Fix unsafe optimisation]
[mel@csn.ul.ie: do not schedule work on other CPUs for compaction]
Signed-off-by: Mel Gorman 
Acked-by: Rik van Riel 
Reviewed-by: Minchan Kim 
Cc: KOSAKI Motohiro 
Cc: Christoph Lameter 
Cc: KAMEZAWA Hiroyuki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: migration: avoid race between shift_arg_pages() and rmap_walk() during migration by not migrating temporary stacks

2010-05-25T15:06:59+00:00

Page migration requires rmap to be able to find all ptes mapping a page
at all times, otherwise the migration entry can be instantiated, but it
is possible to leave one behind if the second rmap_walk fails to find
the page.  If this page is later faulted, migration_entry_to_page() will
call BUG because the page is locked indicating the page was migrated by
the migration PTE not cleaned up. For example

  kernel BUG at include/linux/swapops.h:105!
  invalid opcode: 0000 [#1] PREEMPT SMP
  ...
  Call Trace:
   [] handle_mm_fault+0x3f8/0x76a
   [] do_page_fault+0x44a/0x46e
   [] page_fault+0x25/0x30
   [] load_elf_binary+0x152a/0x192b
   [] search_binary_handler+0x173/0x313
   [] do_execve+0x219/0x30a
   [] sys_execve+0x43/0x5e
   [] stub_execve+0x6a/0xc0
  RIP  [] migration_entry_wait+0xc1/0x129

There is a race between shift_arg_pages and migration that triggers this
bug.  A temporary stack is setup during exec and later moved.  If
migration moves a page in the temporary stack and the VMA is then removed
before migration completes, the migration PTE may not be found leading to
a BUG when the stack is faulted.

This patch causes pages within the temporary stack during exec to be
skipped by migration.  It does this by marking the VMA covering the
temporary stack with an otherwise impossible combination of VMA flags.
These flags are cleared when the temporary stack is moved to its final
location.

[kamezawa.hiroyu@jp.fujitsu.com: idea for having migration skip temporary stacks]
Signed-off-by: Mel Gorman 
Reviewed-by: KAMEZAWA Hiroyuki 
Reviewed-by: Rik van Riel 
Acked-by: Linus Torvalds 
Cc: Minchan Kim 
Cc: Christoph Lameter 
Cc: Andrea Arcangeli 
Cc: Rik van Riel 
Cc: Peter Zijlstra 
Reviewed-by: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds