Commit Graph

430 Commits

Author SHA1 Message Date
Christoph Lameter
02a68a5ebc [PATCH] Fix zone policy determination
The use k in the inner loop means that the highest zone nr is always used
if any zone of a node is populated.  This means that the policy zone is not
correctly determined on arches that do no use HIGHMEM like ia64.

Change the loop to decrement k which also simplifies the BUG_ON.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:28 -08:00
Christoph Lameter
4be38e351c [PATCH] mm: move determination of policy_zone into page allocator
Currently the function to build a zonelist for a BIND policy has the side
effect to set the policy_zone.  This seems to be a bit strange.  policy
zone seems to not be initialized elsewhere and therefore 0.  Do we police
ZONE_DMA if no bind policy has been used yet?

This patch moves the determination of the zone to apply policies to into
the page allocator.  We determine the zone while building the zonelist for
nodes.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:28 -08:00
Christoph Lameter
1a93205bdf [PATCH] mm: simplify build_zonelists_node by removing the case statement.
Simplify build_zonelists_node by removing the case statement.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:28 -08:00
Con Kolivas
f3fe65122d [PATCH] mm: add populated_zone() helper
There are numerous places we check whether a zone is populated or not.

Provide a helper function to check for populated zones and convert all
checks for zone->present_pages.

Signed-off-by: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:28 -08:00
Andrew Morton
80bfed904c [PATCH] consolidate lru_add_drain() and lru_drain_cache()
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Li Shaohua <shaohua.li@intel.com>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:28 -08:00
Andrew Morton
210fe53030 [PATCH] vmscan: balancing fix
Revert a patch which went into 2.6.8-rc1.  The changelog for that patch was:

  The shrink_zone() logic can, under some circumstances, cause far too many
  pages to be reclaimed.  Say, we're scanning at high priority and suddenly
  hit a large number of reclaimable pages on the LRU.

  Change things so we bale out when SWAP_CLUSTER_MAX pages have been
  reclaimed.

Problem is, this change caused significant imbalance in inter-zone scan
balancing by truncating scans of larger zones.

Suppose, for example, ZONE_HIGHMEM is 10x the size of ZONE_NORMAL.  The zone
balancing algorithm would require that if we're scanning 100 pages of
ZONE_HIGHMEM, we should scan 10 pages of ZONE_NORMAL.  But this logic will
cause the scanning of ZONE_HIGHMEM to bale out after only 32 pages are
reclaimed.  Thus effectively causing smaller zones to be scanned relatively
harder than large ones.

Now I need to remember what the workload was which caused me to write this
patch originally, then fix it up in a different way...

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:27 -08:00
Nick Piggin
41e9b63b35 [PATCH] mm: pfault optimisation
This atomic operation is superfluous: the pte will be added with the
referenced bit set, and the page will be referenced through this mapping after
the page fault handler returns anyway.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:27 -08:00
Nick Piggin
9617d95e6e [PATCH] mm: rmap optimisation
Optimise rmap functions by minimising atomic operations when we know there
will be no concurrent modifications.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:27 -08:00
Nick Piggin
224abf92b2 [PATCH] mm: bad_page optimisation
Cut down size slightly by not passing bad_page the function name (it should be
able to be determined by dump_stack()).  And cut down the number of printks in
bad_page.

Also, cut down some branching in the destroy_compound_page path.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:26 -08:00
Nick Piggin
9328b8faae [PATCH] mm: dma32 zone statistics
Add dma32 to zone statistics.  Also attempt to arrange struct page_state a
bit better (visually).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:26 -08:00
Andrew Morton
7756b9e4e3 [PATCH] kill last zone_reclaim() bits
Remove the last bits of Martin's ill-fated sys_set_zone_reclaim().

Cc: Martin Hicks <mort@wildopensource.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:26 -08:00
Nikita Danilov
bbfbb7cec9 [PATCH] find_lock_page(): call __lock_page() directly.
As find_lock_page() already checks with TestSetPageLocked() that page is
locked, there is no need to call lock_page() that will try-lock page again
(chances of page being unlocked in between are small).  Call __lock_page()
directly, this saves one atomic operation.

Also, mark truncate-while-slept path as unlikely while we are here.

(akpm: ug.  But this is actually a common path for normal old read()s against
a page which is under readahead I/O so ho-hum.)

Signed-off-by: Nikita Danilov <danilov@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:26 -08:00
David Howells
a226f6c899 [PATCH] FRV: Clean up bootmem allocator's page freeing algorithm
The attached patch cleans up the way the bootmem allocator frees pages.

A new function, __free_pages_bootmem(), is provided in mm/page_alloc.c that is
called from mm/bootmem.c to turn pages over to the main allocator.  All the
bits of code to initialise pages (clearing PG_reserved and setting the page
count) are moved to here.  The checks on page validity are removed, on the
assumption that the struct page arrays will have been prepared correctly.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:26 -08:00
Ravikiran G Thirumalai
008857c1a4 [PATCH] Cleanup bootmem allocator and fix alloc_bootmem_low
Patch cleans up the alloc_bootmem fix for swiotlb.  Patch removes
alloc_bootmem_*_limit api and fixes alloc_boot_*low api to do the right
thing -- allocate from low32 memory.

Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:26 -08:00
Nick Piggin
085cc7d5de [PATCH] mm: page_alloc cleanups
Small cleanups that does not change generated code with the gcc's I've tested
with.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:25 -08:00
Nick Piggin
a86b1f5316 [PATCH] mm: page_state fixes
read_page_state and __get_page_state only traverse online CPUs, which will
cause results to fluctuate when CPUs are plugged in or out.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:25 -08:00
Nick Piggin
2d92c5c915 [PATCH] mm: remove pcp low
struct per_cpu_pages.low is useless.  Remove it.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:25 -08:00
Nick Piggin
13e7444b0e [PATCH] mm: remove bad_range
bad_range is supposed to be a temporary check.  It would be a pity to throw it
out.  Make it depend on CONFIG_DEBUG_VM instead.

CONFIG_HOLES_IN_ZONE systems were relying on this to check pfn_valid in the
page allocator.  Add that to page_is_buddy instead.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:25 -08:00
Nick Piggin
92be2e33b1 [PATCH] mm: microopt conditions
Micro optimise some conditionals where we don't need lazy evaluation.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:25 -08:00
Nick Piggin
77a8a78834 [PATCH] mm: set_page_refs opt
Inline set_page_refs.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:25 -08:00
Nick Piggin
c54ad30c78 [PATCH] mm: pagealloc opt
Slightly optimise some page allocation and freeing functions by taking
advantage of knowing whether or not interrupts are disabled.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:25 -08:00
Hugh Dickins
c484d41042 [PATCH] mm: free_pages_and_swap_cache opt
Minor optimization (though it doesn't help in the PREEMPT case, severely
constrained by small ZAP_BLOCK_SIZE).  free_pages_and_swap_cache works in
chunks of 16, calling release_pages which works in chunks of PAGEVEC_SIZE.
But PAGEVEC_SIZE was dropped from 16 to 14 in 2.6.10, so we're now doing more
spin_lock_irq'ing than necessary: use PAGEVEC_SIZE throughout.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:24 -08:00
Mike Kravetz
a94b3ab7ea [PATCH] mm: remove arch independent NODES_SPAN_OTHER_NODES
The NODES_SPAN_OTHER_NODES config option was created so that DISCONTIGMEM
could handle pSeries numa layouts.  However, support for DISCONTIGMEM has
been replaced by SPARSEMEM on powerpc.  As a result, this config option and
supporting code is no longer needed.

I have already sent a patch to Paul that removes the option from powerpc
specific code.  This removes the arch independent piece.  Doesn't really
matter which is applied first.

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:24 -08:00
Christoph Lameter
6bda666a03 [PATCH] hugepages: fold find_or_alloc_pages into huge_no_page()
The number of parameters for find_or_alloc_page increases significantly after
policy support is added to huge pages.  Simplify the code by folding
find_or_alloc_huge_page() into hugetlb_no_page().

Adam Litke objected to this piece in an earlier patch but I think this is a
good simplification.  Diffstat shows that we can get rid of almost half of the
lines of find_or_alloc_page().  If we can find no consensus then lets simply
drop this patch.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Acked-by: William Lee Irwin III <wli@holomorphy.com>
Cc: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:23 -08:00
Christoph Lameter
21abb1478a [PATCH] Remove old node based policy interface from mempolicy.c
mempolicy.c contains provisional interface for huge page allocation based on
node numbers.  This is in use in SLES9 but was never used (AFAIK) in upstream
versions of Linux.

Huge page allocations now use zonelists to figure out where to allocate pages.
 The use of zonelists allows us to find the closest hugepage which was the
consideration of the NUMA distance for huge page allocations.

Remove the obsolete functions.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Acked-by: William Lee Irwin III <wli@holomorphy.com>
Cc: Adam Litke <agl@us.ibm.com>
Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:23 -08:00
Christoph Lameter
5da7ca8607 [PATCH] Add NUMA policy support for huge pages.
The huge_zonelist() function in the memory policy layer provides an list of
zones ordered by NUMA distance.  The hugetlb layer will walk that list looking
for a zone that has available huge pages but is also in the nodeset of the
current cpuset.

This patch does not contain the folding of find_or_alloc_huge_page() that was
controversial in the earlier discussion.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Acked-by: William Lee Irwin III <wli@holomorphy.com>
Cc: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:23 -08:00
Christoph Lameter
96df9333c9 [PATCH] mm: dequeue a huge page near to this node
This was discussed at
http://marc.theaimsgroup.com/?l=linux-kernel&m=113166526217117&w=2

This patch changes the dequeueing to select a huge page near the node
executing instead of always beginning to check for free nodes from node 0.
This will result in a placement of the huge pages near the executing
processor improving performance.

The existing implementation can place the huge pages far away from the
executing processor causing significant degradation of performance.  The
search starting from zero also means that the lower zones quickly run out
of memory.  Selecting a huge page near the process distributed the huge
pages better.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:23 -08:00
David Gibson
1e8f889b10 [PATCH] Hugetlb: Copy on Write support
Implement copy-on-write support for hugetlb mappings so MAP_PRIVATE can be
supported.  This helps us to safely use hugetlb pages in many more
applications.  The patch makes the following changes.  If needed, I also have
it broken out according to the following paragraphs.

1. Add a pair of functions to set/clear write access on huge ptes.  The
   writable check in make_huge_pte is moved out to the caller for use by COW
   later.

2. Hugetlb copy-on-write requires special case handling in the following
   situations:

   - copy_hugetlb_page_range() - Copied pages must be write protected so
     a COW fault will be triggered (if necessary) if those pages are written
     to.

   - find_or_alloc_huge_page() - Only MAP_SHARED pages are added to the
     page cache.  MAP_PRIVATE pages still need to be locked however.

3. Provide hugetlb_cow() and calls from hugetlb_fault() and
   hugetlb_no_page() which handles the COW fault by making the actual copy.

4. Remove the check in hugetlbfs_file_map() so that MAP_PRIVATE mmaps
   will be allowed.  Make MAP_HUGETLB exempt from the depricated VM_RESERVED
   mapping check.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:23 -08:00
Adam Litke
86e5216f8d [PATCH] Hugetlb: Reorganize hugetlb_fault to prepare for COW
This patch splits the "no_page()" type activity into its own function,
hugetlb_no_page().  hugetlb_fault() becomes the entry point for hugetlb faults
and delegates to the appropriate handler depending on the type of fault.
Right now we still have only hugetlb_no_page() but a later patch introduces a
COW fault.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:22 -08:00
Adam Litke
85ef47f74a [PATCH] Hugetlb: Rename find_lock_page to find_or_alloc_huge_page
find_lock_huge_page() isn't a great name, since it does extra things not
analagous to find_lock_page().  Rename it find_or_alloc_huge_page() which is
closer to the mark.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:22 -08:00
Adam Litke
f0916794f0 [PATCH] Hugetlb: Remove duplicate i_size check
cleanup

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:22 -08:00
Badari Pulavarty
f6b3ec238d [PATCH] madvise(MADV_REMOVE): remove pages from tmpfs shm backing store
Here is the patch to implement madvise(MADV_REMOVE) - which frees up a
given range of pages & its associated backing store.  Current
implementation supports only shmfs/tmpfs and other filesystems return
-ENOSYS.

"Some app allocates large tmpfs files, then when some task quits and some
client disconnect, some memory can be released.  However the only way to
release tmpfs-swap is to MADV_REMOVE". - Andrea Arcangeli

Databases want to use this feature to drop a section of their bufferpool
(shared memory segments) - without writing back to disk/swap space.

This feature is also useful for supporting hot-plug memory on UML.

Concerns raised by Andrew Morton:

- "We have no plan for holepunching!  If we _do_ have such a plan (or
  might in the future) then what would the API look like?  I think
  sys_holepunch(fd, start, len), so we should start out with that."

- Using madvise is very weird, because people will ask "why do I need to
  mmap my file before I can stick a hole in it?"

- None of the other madvise operations call into the filesystem in this
  manner.  A broad question is: is this capability an MM operation or a
  filesytem operation?  truncate, for example, is a filesystem operation
  which sometimes has MM side-effects.  madvise is an mm operation and with
  this patch, it gains FS side-effects, only they're really, really
  significant ones."

Comments:

- Andrea suggested the fs operation too but then it's more efficient to
  have it as a mm operation with fs side effects, because they don't
  immediatly know fd and physical offset of the range.  It's possible to
  fixup in userland and to use the fs operation but it's more expensive,
  the vmas are already in the kernel and we can use them.

Short term plan &  Future Direction:

- We seem to need this interface only for shmfs/tmpfs files in the short
  term.  We have to add hooks into the filesystem for correctness and
  completeness.  This is what this patch does.

- In the future, plan is to support both fs and mmap apis also.  This
  also involves (other) filesystem specific functions to be implemented.

- Current patch doesn't support VM_NONLINEAR - which can be addressed in
  the future.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrea Arcangeli <andrea@suse.de>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:22 -08:00
Hans Reiser
d7339071f6 [PATCH] reiser4: vfs: add truncate_inode_pages_range()
This patch makes truncate_inode_pages_range from truncate_inode_pages.
truncate_inode_pages became a one-liner call to truncate_inode_pages_range.

Reiser4 needs truncate_inode_pages_ranges because it tries to keep
correspondence between existences of metadata pointing to data pages and pages
to which those metadata point to.  So, when metadata of certain part of file
is removed from filesystem tree, only pages of corresponding range are to be
truncated.

(Needed by the madvise(MADV_REMOVE) patch)

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:22 -08:00
Andy Whitcroft
5ac24eefd1 [PATCH] memhotplug: __add_section remove unused pgdat definition
__add_section defines an unused pointer to the zones pgdat.  Remove this
definition.  This fixes a compile warning.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:21 -08:00
Paul Jackson
47f3a867f6 [PATCH] mm: fix __alloc_pages cpuset ALLOC_* flags
Two changes to the setting of the ALLOC_CPUSET flag in
mm/page_alloc.c:__alloc_pages()

- A bug fix - the "ignoring mins" case should not be honoring ALLOC_CPUSET.
  This case of all cases, since it is handling a request that will free up
  more memory than is asked for (exiting tasks, e.g.) should be allowed to
  escape cpuset constraints when memory is tight.

- A logic change to make it simpler.  Honor cpusets even on GFP_ATOMIC
  (!wait) requests.  With this, cpuset confinement applies to all requests
  except ALLOC_NO_WATERMARKS, so that in a subsequent cleanup patch, I can
  remove the ALLOC_CPUSET flag entirely.  Since I don't know any real reason
  this logic has to be either way, I am choosing the path of the simplest
  code.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:21 -08:00
Zach Brown
994fc28c7b [PATCH] add AOP_TRUNCATED_PAGE, prepend AOP_ to WRITEPAGE_ACTIVATE
readpage(), prepare_write(), and commit_write() callers are updated to
understand the special return code AOP_TRUNCATED_PAGE in the style of
writepage() and WRITEPAGE_ACTIVATE.  AOP_TRUNCATED_PAGE tells the caller that
the callee has unlocked the page and that the operation should be tried again
with a new page.  OCFS2 uses this to detect and work around a lock inversion in
its aop methods.  There should be no change in behaviour for methods that don't
return AOP_TRUNCATED_PAGE.

WRITEPAGE_ACTIVATE is also prepended with AOP_ for consistency and they are
made enums so that kerneldoc can be used to document their semantics.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2006-01-03 11:45:42 -08:00
Andi Kleen
8f493d797b [PATCH] Make sure interleave masks have at least one node set
Otherwise a bad mem policy system call can confuse the interleaving
code into referencing undefined nodes.

Originally reported by Doug Chapman

I was told it's CVE-2005-3358
(one has to love these security people - they make everything sound important)

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-02 17:01:42 -08:00
Linus Torvalds
4d7672b462 Make sure we copy pages inserted with "vm_insert_page()" on fork
The logic that decides that a fork() might be able to avoid copying a VM
area when it can be re-created by page faults didn't know about the new
vm_insert_page() case.

Also make some things a bit more anal wrt VM_PFNMAP.

Pointed out by Hugh Dickins <hugh@veritas.com>

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-16 10:21:23 -08:00
Al Viro
78d9955bb0 [PATCH] missing prototype (mm/page_alloc.c)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:04:30 -08:00
Yasunori Goto
118c71bcac [PATCH] Fix calculation of grow_pgdat_span() in mm/memory_hotplug.c
The calculation for node_spanned_pages at grow_pgdat_span() is clearly
wrong.  This is patch for it.

(Please see grow_zone_span() to compare. It is correct.)

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Acked-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-13 21:18:16 -08:00
Linus Torvalds
1ff8038988 get_user_pages: don't try to follow PFNMAP pages
Nick Piggin points out that a few drivers play games with VM_IO (why?
who knows..) and thus a pfn-remapped area may not have that bit set even
if remap_pfn_range() set it originally.

So make it explicit in get_user_pages() that we don't follow VM_PFNMAP
pages, since pretty much by definition they do not have a "struct page"
associated with them.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-12 16:24:33 -08:00
Haren Myneni
66d43e98ea [PATCH] fix in __alloc_bootmem_core() when there is no free page in first node's memory
Hitting BUG_ON() in __alloc_bootmem_core() when there is no free page
available in the first node's memory.  For the case of kdump on PPC64
(Power 4 machine), the captured kernel is used two memory regions - memory
for TCE tables (tce-base and tce-size at top of RAM and reserved) and
captured kernel memory region (crashk_base and crashk_size).  Since we
reserve the memory for the first node, we should be returning from
__alloc_bootmem_core() to search for the next node (pg_dat).

Currently, find_next_zero_bit() is returning the n^th bit (eidx) when there
is no free page.  Then, test_bit() is failed since we set 0xff only for the
actual size initially (init_bootmem_core()) even though rounded up to one
page for bdata->node_bootmem_map.  We are hitting the BUG_ON after failing
to enter second "for" loop.

Signed-off-by: Haren Myneni <haren@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-12 08:57:45 -08:00
Linus Torvalds
67121172f9 Allow arbitrary read-only shared pfn-remapping too
The VM layer (for historical reasons) turns a read-only shared mmap into
a private-like mapping with the VM_MAYWRITE bit clear.  Thus checking
just VM_SHARED isn't actually sufficient.

So use a trivial helper function for the cases where we wanted to inquire
if a mapping was COW-like or not.

Moo!

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-11 20:38:17 -08:00
Linus Torvalds
7fc7e2eeec Remove (at least temporarily) the "incomplete PFN mapping" support
With the previous commit, we can handle arbitrary shared re-mappings
even without this complexity, and since the only known private mappings
are for strange users of /dev/mem (which never create an incomplete one),
there seems to be no reason to support it.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-11 19:57:52 -08:00
Linus Torvalds
fb155c1619 Allow arbitrary shared PFNMAP's
A shared mapping doesn't cause COW-pages, so we don't need to worry
about the whole vm_pgoff logic to decide if a PFN-remapped page has
gone through COW or not.

This makes it possible to entirely avoid the special "partial remapping"
logic for the common case.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-11 19:46:02 -08:00
Linus Torvalds
e3c3374fbf Make vm_insert_page() available to NVidia module
It used to use remap_pfn_range(), which wasn't GPL-only either, and the
new interface is actually simpler and does more checking, so we
shouldn't unnecessarily discourage people from switching over.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-03 20:48:11 -08:00
Nick Piggin
0ceaacc978 [PATCH] Fix up per-cpu page batch sizes
The code to clamp batch sizes to 2^n - 1 went missing and an extra
check got added, which must have been a hunk of the "higer order pcp
batch refills" work sneaking in.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-03 20:46:40 -08:00
Linus Torvalds
a145dd411e VM: add "vm_insert_page()" function
This is what a lot of drivers will actually want to use to insert
individual pages into a user VMA.  It doesn't have the old PageReserved
restrictions of remap_pfn_range(), and it doesn't complain about partial
remappings.

The page you insert needs to be a nice clean kernel allocation, so you
can't insert arbitrary page mappings with this, but that's not what
people want.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-30 09:35:19 -08:00
Trond Myklebust
49c91fb01f [PATCH] VM: Fix typos in get_locked_pte
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-29 17:29:57 -08:00
Hugh Dickins
325f04dbca [PATCH] pfnmap: do_no_page BUG_ON again
Use copy_user_highpage directly instead of cow_user_page in do_no_page:
in the immediately following page_cache_release, and elsewhere, it is
assuming that new_page is normal.  If any VM_PFNMAP driver can get to
do_no_page, it's just a BUG (but not in the case of do_anonymous_page).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-29 14:09:17 -08:00
Hugh Dickins
e5bbe4dfc8 [PATCH] pfnmap: remove src_page from do_wp_page
Clean away do_wp_page's "src_page": cow_user_page makes it unnecessary.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-29 14:09:16 -08:00
Linus Torvalds
5d2a2dbbc1 cow_user_page: fix page alignment
High Dickins points out that the user virtual address passed to the page
fault handler isn't necessarily page-aligned.

Also, add a comment on why the copy could fail for the user address case.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-29 14:07:55 -08:00
Linus Torvalds
c9cfcddfd6 VM: add common helper function to create the page tables
This logic was duplicated four times, for no good reason.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-29 14:03:14 -08:00
Linus Torvalds
238f58d898 Support strange discontiguous PFN remappings
These get created by some drivers that don't generally even want a pfn
remapping at all, but would really mostly prefer to just map pages
they've allocated individually instead.

For now, create a helper function that turns such an incomplete PFN
remapping call into a loop that does that explicit mapping.  In the long
run we almost certainly want to export a totally different interface for
that, though.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-29 13:01:56 -08:00
Ben Collins
eca351336a [PATCH] Fix missing pfn variables caused by vm changes
I image this showed up because of "unused var..." when the changes
occured, because flush_cache_page() is a noop in most places.  This
showed up for me on parisc however, where flush_cache_page() is a real
function.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-29 12:57:17 -08:00
Nick Piggin
fa2a455b02 [PATCH] Fix vma argument in get_usr_pages() for gate areas
The system call gate area handling called vm_normal_page() with the
wrong vma (which was always NULL, and caused an oops).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-29 07:53:32 -08:00
Andrea Arcangeli
ea164d73a7 [PATCH] shrinker->nr = LONG_MAX means deadlock for icache
With Andrew Morton <akpm@osdl.org>

The slab scanning code tries to balance the scanning rate of slabs versus the
scanning rate of LRU pages.  To do this, it retains state concerning how many
slabs have been scanned - if a particular slab shrinker didn't scan enough
objects, we remember that for next time, and scan more objects on the next
pass.

The problem with this is that with (say) a huge number of GFP_NOIO
direct-reclaim attempts, the number of objects which are to be scanned when we
finally get a GFP_KERNEL request can be huge.  Because some shrinker handlers
just bail out if !__GFP_FS.

So the patch clamps the number of objects-to-be-scanned to 2* the total number
of objects in the slab cache.

Signed-off-by: Andrea Arcangeli <andrea@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-28 14:42:26 -08:00
Rik van Riel
f7b7fd8f3e [PATCH] temporarily disable swap token on memory pressure
Some users (hi Zwane) have seen a problem when running a workload that
eats nearly all of physical memory - th system does an OOM kill, even
when there is still a lot of swap free.

The problem appears to be a very big task that is holding the swap
token, and the VM has a very hard time finding any other page in the
system that is swappable.

Instead of ignoring the swap token when sc->priority reaches 0, we could
simply take the swap token away from the memory hog and make sure we
don't give it back to the memory hog for a few seconds.

This patch resolves the problem Zwane ran into.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-28 14:42:25 -08:00
Nick Piggin
3148890bfa [PATCH] mm: __alloc_pages cleanup fix
I believe this patch is required to fix breakage in the asynch reclaim
watermark logic introduced by this patch:

http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=7fb1d9fca5c6e3b06773b69165a73f3fb786b8ee

Just some background of the watermark logic in case it isn't clear...
Basically what we have is this:

 ---  pages_high
   |
   | (a)
   |
 ---  pages_low
   |
   | (b)
   |
 ---  pages_min
   |
   | (c)
   |
 ---  0

Now when pages_low is reached, we want to kick asynch reclaim, which gives us
an interval of "b" before we must start synch reclaim, and gives kswapd an
interval of "a" before it need go back to sleep.

When pages_min is reached, normal allocators must enter synch reclaim, but
PF_MEMALLOC, ALLOC_HARDER, and ALLOC_HIGH (ie.  atomic allocations, recursive
allocations, etc.) get access to varying amounts of the reserve "c".

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-28 14:42:24 -08:00
Alan Stern
e0f39591cc [PATCH] Workaround for gcc 2.96 (undefined references)
LD      .tmp_vmlinux1
mm/built-in.o(.text+0x100d6): In function `copy_page_range':
: undefined reference to `__pud_alloc'
mm/built-in.o(.text+0x1010b): In function `copy_page_range':
: undefined reference to `__pmd_alloc'
mm/built-in.o(.text+0x11ef4): In function `__handle_mm_fault':
: undefined reference to `__pud_alloc'
fs/built-in.o(.text+0xc930): In function `install_arg_page':
: undefined reference to `__pud_alloc'
make: *** [.tmp_vmlinux1] Error 1

Those missing references in mm/memory.c arise from this code in
include/linux/mm.h, combined with the fact that __PGTABLE_PMD_FOLDED and
__PGTABLE_PUD_FOLDED are both set and __ARCH_HAS_4LEVEL_HACK is not:

/*
 * The following ifdef needed to get the 4level-fixup.h header to work.
 * Remove it when 4level-fixup.h has been removed.
 */
#if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK)
static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
{
        return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))?
                NULL: pud_offset(pgd, address);
}

static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
{
        return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
                NULL: pmd_offset(pud, address);
}
#endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */

With my configuration the pgd_none and pud_none routines are inlines
returning a constant 0.  Apparently the old compiler avoids generating
calls to __pud_alloc and __pmd_alloc but still lists them as undefined
references in the module's symbol table.

I don't know which change caused this problem.  I think it was added
somewhere between 2.6.14 and 2.6.15-rc1, because I remember building
several 2.6.14-rc kernels without difficulty.  However I can't point to an
individual culprit.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-28 14:42:22 -08:00
Linus Torvalds
6aab341e0a mm: re-architect the VM_UNPAGED logic
This replaces the (in my opinion horrible) VM_UNMAPPED logic with very
explicit support for a "remapped page range" aka VM_PFNMAP.  It allows a
VM area to contain an arbitrary range of page table entries that the VM
never touches, and never considers to be normal pages.

Any user of "remap_pfn_range()" automatically gets this new
functionality, and doesn't even have to mark the pages reserved or
indeed mark them any other way.  It just works.  As a side effect, doing
mmap() on /dev/mem works for arbitrary ranges.

Sparc update from David in the next commit.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-28 14:34:23 -08:00
Oleg Drokin
479ef592f3 [PATCH] 32bit integer overflow in invalidate_inode_pages2()
Fix a 32 bit integer overflow in invalidate_inode_pages2_range.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-23 16:08:39 -08:00
Hugh Dickins
7b6ac9dffe [PATCH] mm: update split ptlock Kconfig
Closer attention to the arithmetic shows that neither ppc64 nor sparc really
uses one page for multiple page tables: how on earth could they, while
pte_alloc_one returns just a struct page pointer, with no offset?

Well, arm26 manages it by returning a pte_t pointer cast to a struct page
pointer, harumph, then compensating in its pmd_populate.  But arm26 is never
SMP, so it's not a problem for split ptlock either.

And the PA-RISC situation has been recently improved: CONFIG_PA20 works
without the 16-byte alignment which inflated its spinlock_t.  But the current
union of spinlock_t with private does make the 7xxx struct page significantly
larger, even without debug, so disable its split ptlock.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-23 16:08:38 -08:00
Eric Paris
0bd0f9fb19 [PATCH] hugetlb: fix race in set_max_huge_pages for multiple updaters of nr_huge_pages
If there are multiple updaters to /proc/sys/vm/nr_hugepages simultaneously
it is possible for the nr_huge_pages variable to become incorrect.  There
is no locking in the set_max_huge_pages function around
alloc_fresh_huge_page which is able to update nr_huge_pages.  Two callers
to alloc_fresh_huge_page could race against each other as could a call to
alloc_fresh_huge_page and a call to update_and_free_page.  This patch just
expands the area covered by the hugetlb_lock to cover the call into
alloc_fresh_huge_page.  I'm not sure how we could say that a sysctl section
is performance critical where more specific locking would be needed.

My reproducer was to run a couple copies of the following script
simultaneously

while [ true ]; do
	echo 1000 > /proc/sys/vm/nr_hugepages
	echo 500 > /proc/sys/vm/nr_hugepages
	echo 750 > /proc/sys/vm/nr_hugepages
	echo 100 > /proc/sys/vm/nr_hugepages
	echo 0 > /proc/sys/vm/nr_hugepages
done

and then watch /proc/meminfo and eventually you will see things like

HugePages_Total:     100
HugePages_Free:      109

After applying the patch all seemed well.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: William Irwin <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:43 -08:00
Hugh Dickins
689bcebfda [PATCH] unpaged: PG_reserved bad_page
It used to be the case that PG_reserved pages were silently never freed, but
in 2.6.15-rc1 they may be freed with a "Bad page state" message.  We should
work through such cases as they appear, fixing the code; but for now it's
safer to issue the message without freeing the page, leaving PG_reserved set.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Hugh Dickins
f57e88a8d8 [PATCH] unpaged: ZERO_PAGE in VM_UNPAGED
It's strange enough to be looking out for anonymous pages in VM_UNPAGED areas,
let's not insert the ZERO_PAGE there - though whether it would matter will
depend on what we decide about ZERO_PAGE refcounting.

But whereas do_anonymous_page may (exceptionally) be called on a VM_UNPAGED
area, do_no_page should never be: just BUG_ON.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Hugh Dickins
ee498ed730 [PATCH] unpaged: anon in VM_UNPAGED
copy_one_pte needs to copy the anonymous COWed pages in a VM_UNPAGED area,
zap_pte_range needs to free them, do_wp_page needs to COW them: just like
ordinary pages, not like the unpaged.

But recognizing them is a little subtle: because PageReserved is no longer a
condition for remap_pfn_range, we can now mmap all of /dev/mem (whether the
distro permits, and whether it's advisable on this or that architecture, is
another matter).  So if we can see a PageAnon, it may not be ours to mess with
(or may be ours from elsewhere in the address space).  I suspect there's an
entertaining insoluble self-referential problem here, but the page_is_anon
function does a good practical job, and MAP_PRIVATE PROT_WRITE VM_UNPAGED will
always be an odd choice.

In updating the comment on page_address_in_vma, noticed a potential NULL
dereference, in a path we don't actually take, but fixed it.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Hugh Dickins
920fc356f5 [PATCH] unpaged: COW on VM_UNPAGED
Remove the BUG_ON(vma->vm_flags & VM_UNPAGED) from do_wp_page, and let it do
Copy-On-Write without touching the VM_UNPAGED's page counts - but this is
incomplete, because the anonymous page it inserts will itself need to be
handled, here and in other functions - next patch.

We still don't copy the page if the pfn is invalid, because the
copy_user_highpage interface does not allow it.  But that's not been a problem
in the past: can be added in later if the need arises.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Hugh Dickins
101d2be764 [PATCH] unpaged: VM_NONLINEAR VM_RESERVED
There's one peculiar use of VM_RESERVED which the previous patch left behind:
because VM_NONLINEAR's try_to_unmap_cluster uses vm_private_data as a swapout
cursor, but should never meet VM_RESERVED vmas, it was a way of extending
VM_NONLINEAR to VM_RESERVED vmas using vm_private_data for some other purpose.
 But that's an empty set - they don't have the populate function required.  So
just throw away those VM_RESERVED tests.

But one more interesting in rmap.c has to go too: try_to_unmap_one will want
to swap out an anonymous page from VM_RESERVED or VM_UNPAGED area.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Hugh Dickins
0b14c179a4 [PATCH] unpaged: VM_UNPAGED
Although we tend to associate VM_RESERVED with remap_pfn_range, quite a few
drivers set VM_RESERVED on areas which are then populated by nopage.  The
PageReserved removal in 2.6.15-rc1 changed VM_RESERVED not to free pages in
zap_pte_range, without changing those drivers not to set it: so their pages
just leak away.

Let's not change miscellaneous drivers now: introduce VM_UNPAGED at the core,
to flag the special areas where the ptes may have no struct page, or if they
have then it's not to be touched.  Replace most instances of VM_RESERVED in
core mm by VM_UNPAGED.  Force it on in remap_pfn_range, and the sparc and
sparc64 io_remap_pfn_range.

Revert addition of VM_RESERVED to powerpc vdso, it's not needed there.  Is it
needed anywhere?  It still governs the mm->reserved_vm statistic, and special
vmas not to be merged, and areas not to be core dumped; but could probably be
eliminated later (the drivers are probably specifying it because in 2.4 it
kept swapout off the vma, but in 2.6 we work from the LRU, which these pages
don't get on).

Use the VM_SHM slot for VM_UNPAGED, and define VM_SHM to 0: it serves no
purpose whatsoever, and should be removed from drivers when we clean up.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: William Irwin <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Hugh Dickins
664beed019 [PATCH] unpaged: unifdefed PageCompound
It looks like snd_xxx is not the only nopage to be using PageReserved as a way
of holding a high-order page together: which no longer works, but is masked by
our failure to free from VM_RESERVED areas.  We cannot fix that bug without
first substituting another way to hold the high-order page together, while
farming out the 0-order pages from within it.

That's just what PageCompound is designed for, but it's been kept under
CONFIG_HUGETLB_PAGE.  Remove the #ifdefs: which saves some space (out- of-line
put_page), doesn't slow down what most needs to be fast (already using
hugetlb), and unifies the way we handle high-order pages.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Hugh Dickins
83e9b7e929 [PATCH] unpaged: private write VM_RESERVED
The PageReserved removal in 2.6.15-rc1 issued a "deprecated" message when you
tried to mmap or mprotect MAP_PRIVATE PROT_WRITE a VM_RESERVED, and failed
with -EACCES: because do_wp_page lacks the refinement to COW pages in those
areas, nor do we expect to find anonymous pages in them; and it seemed just
bloat to add code for handling such a peculiar case.  But immediately it
caused vbetool and ddcprobe (using lrmi) to fail.

So revert the "deprecated" messages, letting mmap and mprotect succeed.  But
leave do_wp_page's BUG_ON(vma->vm_flags & VM_RESERVED) in place until we've
added the code to do it right: so this particular patch is only good if the
app doesn't really need to write to that private area.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Hugh Dickins
ed5297a940 [PATCH] unpaged: get_user_pages VM_RESERVED
The PageReserved removal in 2.6.15-rc1 prohibited get_user_pages on the areas
flagged VM_RESERVED in place of PageReserved.  That is correct in theory - we
ought not to interfere with struct pages in such a reserved area; but in
practice it broke BTTV for one.

So revert to prohibiting only on VM_IO: if someone gets into trouble with
get_user_pages on VM_RESERVED, it'll just be a "don't do that".

You can argue that videobuf_mmap_mapper shouldn't set VM_RESERVED in the first
place, but now's not the time for breaking drivers without notice.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:41 -08:00
Kyle McMartin
2161558fa5 Merge branch 'master' 2005-11-18 16:39:20 -05:00
Matthew Wilcox
9ab8851549 [PARISC] Fix compile warning caused by conflicting types of expand_upwards()
Fix compile warning caused by conflicting types of expand_upwards. IA64
requires it to not be static inline, as it's used outside mm/mmap.c

Signed-off-by: Matthew Wilcox <willy@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2005-11-18 16:16:42 -05:00
Hans Reiser
58bb01a9cd [PATCH] re-export clear_page_dirty_for_io()
2.6.14 has this exported, and reiser4 (at least) uses it.  Put things back
the way they were.

Signed-off-by: Vladimir V. Saveliev <vs@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-18 07:49:45 -08:00
Jens Axboe
6b1de9161e [PATCH] VM: fix zone list restart in page allocatate
We must reassign z before looping through the zones kicking kswapd,
since it will be NULL if we hit an OOM condition and jump back to the
beginning again. 'z' is initially assigned before the restart: label. So
move the restart label up a little.

Signed-off-by: Jens Axboe <axboe@suse.de>
2005-11-17 12:43:01 -08:00
Linus Torvalds
4060994c3e Merge x86-64 update from Andi 2005-11-14 19:56:02 -08:00
Andi Kleen
07808b74e7 [PATCH] x86_64: Remove obsolete ARCH_HAS_ATOMIC_UNSIGNED and page_flags_t
Has been introduced for x86-64 at some point to save memory
in struct page, but has been obsolete for some time. Just
remove it.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-14 19:55:14 -08:00
Andi Kleen
b0d4169321 [PATCH] x86_64: When cpu_up fails clean up page allocator properly
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-14 19:55:13 -08:00
Andi Kleen
a2f1b42490 [PATCH] x86_64: Add 4GB DMA32 zone
Add a new 4GB GFP_DMA32 zone between the GFP_DMA and GFP_NORMAL zones.

As a bit of historical background: when the x86-64 port
was originally designed we had some discussion if we should
use a 16MB DMA zone like i386 or a 4GB DMA zone like IA64 or
both. Both was ruled out at this point because it was in early
2.4 when VM is still quite shakey and had bad troubles even
dealing with one DMA zone.  We settled on the 16MB DMA zone mainly
because we worried about older soundcards and the floppy.

But this has always caused problems since then because
device drivers had trouble getting enough DMA able memory. These days
the VM works much better and the wide use of NUMA has proven
it can deal with many zones successfully.

So this patch adds both zones.

This helps drivers who need a lot of memory below 4GB because
their hardware is not accessing more (graphic drivers - proprietary
and free ones, video frame buffer drivers, sound drivers etc.).
Previously they could only use IOMMU+16MB GFP_DMA, which
was not enough memory.

Another common problem is that hardware who has full memory
addressing for >4GB misses it for some control structures in memory
(like transmit rings or other metadata).  They tended to allocate memory
in the 16MB GFP_DMA or the IOMMU/swiotlb then using pci_alloc_consistent,
but that can tie up a lot of precious 16MB GFPDMA/IOMMU/swiotlb memory
(even on AMD systems the IOMMU tends to be quite small) especially if you have
many devices.  With the new zone pci_alloc_consistent can just put
this stuff into memory below 4GB which works better.

One argument was still if the zone should be 4GB or 2GB. The main
motivation for 2GB would be an unnamed not so unpopular hardware
raid controller (mostly found in older machines from a particular four letter
company) who has a strange 2GB restriction in firmware. But
that one works ok with swiotlb/IOMMU anyways, so it doesn't really
need GFP_DMA32. I chose 4GB to be compatible with IA64 and because
it seems to be the most common restriction.

The new zone is so far added only for x86-64.

For other architectures who don't set up this
new zone nothing changes. Architectures can set a compatibility
define in Kconfig CONFIG_DMA_IS_DMA32 that will define GFP_DMA32
as GFP_DMA. Otherwise it's a nop because on 32bit architectures
it's normally not needed because GFP_NORMAL (=0) is DMA able
enough.

One problem is still that GFP_DMA means different things on different
architectures. e.g. some drivers used to have #ifdef ia64  use GFP_DMA
(trusting it to be 4GB) #elif __x86_64__ (use other hacks like
the swiotlb because 16MB is not enough) ... . This was quite
ugly and is now obsolete.

These should be now converted to use GFP_DMA32 unconditionally. I haven't done
this yet. Or best only use pci_alloc_consistent/dma_alloc_coherent
which will use GFP_DMA32 transparently.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-14 19:55:13 -08:00
Christoph Lameter
50c85a19e7 [PATCH] slab: remove alloc_pages() calls
The slab allocator never uses alloc_pages since kmem_getpages() is always
called with a valid nodeid.  Remove the branch and the code from
kmem_getpages()

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:12 -08:00
Pekka Enberg
065d41cb26 [PATCH] slab: convert cache to page mapping macros
This patch converts object cache <-> page mapping macros to static inline
functions to make the more explicit and readable.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:12 -08:00
Nick Piggin
669ed17521 [PATCH] mm: highmem watermarks
The pages_high - pages_low and pages_low - pages_min deltas are the asynch
reclaim watermarks.  As such, the should be in the same ratios as any other
zone for highmem zones.  It is the pages_min - 0 delta which is the
PF_MEMALLOC reserve, and this is the region that isn't very useful for
highmem.

This patch ensures highmem systems have similar characteristics as non highmem
ones with the same amount of memory, and also that highmem zones get similar
reclaim pressures to other zones.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:12 -08:00
Rohit Seth
7fb1d9fca5 [PATCH] mm: __alloc_pages cleanup
Clean up of __alloc_pages.

Restoration of previous behaviour, plus further cleanups by introducing an
'alloc_flags', removing the last of should_reclaim_zone.

Signed-off-by: Rohit Seth <rohit.seth@intel.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:12 -08:00
Robin Holt
51c6f666fc [PATCH] mm: ZAP_BLOCK causes redundant work
The address based work estimate for unmapping (for lockbreak) is and always
was horribly inefficient for sparse mappings.  The problem is most simply
explained with an example:

If we find a pgd is clear, we still have to call into unmap_page_range
PGDIR_SIZE / ZAP_BLOCK_SIZE times, each time checking the clear pgd, in
order to progress the working address to the next pgd.

The fundamental way to solve the problem is to keep track of the end
address we've processed and pass it back to the higher layers.

From: Nick Piggin <npiggin@suse.de>

  Modification to completely get away from address based work estimate
  and instead use an abstract count, with a very small cost for empty
  entries as opposed to present pages.

  On 2.6.14-git2, ppc64, and CONFIG_PREEMPT=y, mapping and unmapping 1TB
  of virtual address space takes 1.69s; with the following patch applied,
  this operation can be done 1000 times in less than 0.01s

From: Andrew Morton <akpm@osdl.org>

With CONFIG_HUTETLB_PAGE=n:

mm/memory.c: In function `unmap_vmas':
mm/memory.c:779: warning: division by zero

Due to

			zap_work -= (end - start) /
					(HPAGE_SIZE / PAGE_SIZE);

So make the dummy HPAGE_SIZE non-zero

Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:12 -08:00
Kirill Korotaev
885036d32f [PATCH] mm: __GFP_NOFAIL fix
In __alloc_pages():

if ((p->flags & (PF_MEMALLOC | PF_MEMDIE)) && !in_interrupt()) {
         /* go through the zonelist yet again, ignoring mins */
         for (i = 0; zones[i] != NULL; i++) {
                 struct zone *z = zones[i];

                 page = buffered_rmqueue(z, order, gfp_mask);
                 if (page) {
                         zone_statistics(zonelist, z);
                         goto got_pg;
                 }
         }
         goto nopage;                <<<< HERE!!! FAIL...
}

kswapd (which has PF_MEMALLOC flag) can fail to allocate memory even when
it allocates it with __GFP_NOFAIL flag.

Signed-Off-By: Pavel Emelianov <xemul@sw.ru>
Signed-Off-By: Denis Lunev <den@sw.ru>
Signed-Off-By: Kirill Korotaev <dev@sw.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:12 -08:00
Linus Torvalds
63f45b8094 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2005-11-11 16:29:22 -08:00
Dave Jones
6b482c6779 [PATCH] Don't print per-cpu vm stats for offline cpus.
I just hit a page allocation error on a kernel configured to support
64 CPUs.  It spewed 60 completely useless unnecessary lines of info.

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-10 13:25:53 -08:00
Adrian Bunk
dc6f3f276e mm/slab.c: fix a comment typo 2005-11-08 16:44:08 +01:00
Adrian Bunk
4936967374 [PATCH] mm/swap_state.c: unexport swapper_space
I didn't find any possible modular usage in the kernel.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:07 -08:00
Adrian Bunk
e2de225710 [PATCH] mm/swapfile.c: unexport total_swap_pages
I didn't find any possible modular usage in the kernel.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:07 -08:00
Adrian Bunk
1b09d16489 [PATCH] mm/swap.c: unexport vm_acct_memory
I didn't find any possible modular usage in the kernel.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:07 -08:00
Adrian Bunk
f8b8db77b0 [PATCH] unexport nr_swap_pages
I didn't find any possible modular usage in the kernel.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:07 -08:00
Adrian Bunk
e6a7e0e7ce [PATCH] unexport clear_page_dirty_for_io
I didn't find any possible modular usage in the kernel.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:06 -08:00
Adrian Bunk
99697dc02d [PATCH] unexport hugetlb_total_pages
I didn't find any possible modular usage in the kernel.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:06 -08:00
Adrian Bunk
55be570c52 [PATCH] mm/{mmap,nommu}.c: several unexports
I didn't find any possible modular usage in the kernel.

This patch was already ACK'ed by Christoph Hellwig.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:06 -08:00
Randy Dunlap
d44e0780bc [PATCH] kernel-doc: fix warnings in vmalloc.c
Fix new kernel-doc errors in vmalloc.c.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:56 -08:00
Randy Dunlap
1e5d533142 [PATCH] more kernel-doc cleanups, additions
Various core kernel-doc cleanups:
- add missing function parameters in ipc, irq/manage, kernel/sys,
  kernel/sysctl, and mm/slab;
- move description to just above function for kernel_restart()

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:55 -08:00
Andrew Morton
7361f4d8ca [PATCH] readahead commentary
Add a few comments surrounding the generic readahead API.

Also convert some ulongs into pgoff_t: the identifier for PAGE_CACHE_SIZE
offsets into pagecache.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:37 -08:00