Commit Graph

29557 Commits

Author SHA1 Message Date
Al Viro
5e591a5557 [PATCH] frv: Add missing qualifier to memcpy_fromio() prototype
The memcpy_fromio() function should have a const qualifier on its source
pointer.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:55 -07:00
Al Viro
a73df4dfdb [PATCH] frv: ieee1394 is borken on frv
The ieee1394 assumes it may make direct use of ->count in the semaphore
structure.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Ben Collins <bcollins@ubuntu.com>
Cc: Jody McIntyre <scjody@modernduck.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:55 -07:00
Al Viro
7f78843556 [PATCH] frv: NULL noise removal in frv xchg()
Clean up the FRV arch's xchg() function.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:55 -07:00
Al Viro
ffca11104c [PATCH] frv: initrd is grossly broken on frv (never built)
The FRV arch doesn't currently support initrd, so it should be disabled
automatically for the moment.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:55 -07:00
Al Viro
0c426f26cc [PATCH] ext2 XIP won't build without MMU
Disable Ext2 XIP if the kernel is configured in no-MMU mode as the former
won't build.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:55 -07:00
Al Viro
be2338f3ce [PATCH] frv: wrong syscall
The FRV arch should use fstatat64 not newfstatat.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:55 -07:00
Al Viro
576132b426 [PATCH] frv: misc sparse annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:55 -07:00
Al Viro
53470aaa02 [PATCH] frv: misc __user annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
Al Viro
530018bf3d [PATCH] frv: binfmt_elf_fdpic __user annotations
Add __user annotations to binfmt_elf_fdpic.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
Al Viro
7ab76d722a [PATCH] frv: sysctl __user annotations
Add __user annotations to FRV-specific sysctl stuff.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
Al Viro
9e4d11f863 [PATCH] frv: signal annotations
Add annotations to the FRV signal handling for sparse.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
Al Viro
3f4cd389c3 [PATCH] frv: basic __iomem annotations
Add annotations to the FRV I/O handling functions for sparse.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
Al Viro
a8a77573c9 [PATCH] frv: __user infrastructure
Add general annotations to the FRV arch for sparse.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
David Quigley
86c3a7645c [PATCH] SELinux: add security_task_movememory calls to mm code
This patch inserts security_task_movememory hook calls into memory management
code to enable security modules to mediate this operation between tasks.

Since the last posting, the hook has been renamed following feedback from
Christoph Lameter.

Signed-off-by: David Quigley <dpquigl@tycho.nsa.gov>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Andi Kleen <ak@muc.de>
Acked-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
David Quigley
35601547ba [PATCH] SELinux: add task_movememory hook
This patch adds new security hook, task_movememory, to be called when memory
owened by a task is to be moved (e.g.  when migrating pages to a this hook is
identical to the setscheduler implementation, but a separate hook introduced
to allow this check to be specialized in the future if necessary.

Since the last posting, the hook has been renamed following feedback from
Christoph Lameter.

Signed-off-by: David Quigley <dpquigl@tycho.nsa.gov>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
David Quigley
22fb52dd73 [PATCH] SELinux: add security hook call to mediate attach_task (kernel/cpuset.c)
Add a security hook call to enable security modules to control the ability
to attach a task to a cpuset.  While limited control over this operation is
possible via permission checks on the pseudo fs interface, those checks are
not sufficient to control access to the target task, which is looked up in
this function.  The existing task_setscheduler hook is re-used for this
operation since this falls under the same class of operations.

Signed-off-by: David Quigley <dpquigl@tycho.nsa.gov>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
David Quigley
e7834f8fcc [PATCH] SELinux: add security hooks to {get,set}affinity
This patch adds LSM hooks into the setaffinity and getaffinity functions to
enable security modules to control these operations between tasks with
task_setscheduler and task_getscheduler LSM hooks.

Signed-off-by: David Quigley <dpquigl@tycho.nsa.gov>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
James Morris
03e6806063 [PATCH] lsm: add task_setioprio hook
Implement an LSM hook for setting a task's IO priority, similar to the hook
for setting a tasks's nice value.

A previous version of this LSM hook was included in an older version of
multiadm by Jan Engelhardt, although I don't recall it being submitted
upstream.

Also included is the corresponding SELinux hook, which re-uses the setsched
permission in the proccess class.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
9216dfad4f [PATCH] move_pages: fix 32 -> 64 bit compat function
The definition of the third parameter is a pointer to an array of virtual
addresses which give us some trouble.  The existing code calculated the
wrong address in the array since I used void to avoid having to specify a
type.

I now use the correct type "compat_uptr_t __user *" in the definition of
the function in kernel/compat.c.

However, I used __u32 in syscalls.h.  Would have to include compat.h there
in order to provide the same definition which would generate an ugly
include situation.

On both ia64 and x86_64 compat_uptr_t is u32. So this works although
parameter declarations differ.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
1b2db9fb7a [PATCH] sys_move_pages: 32bit support (i386, x86_64)
sys_move_pages() support for 32bit (i386 plus x86_64 compat layer)

Add support for move_pages() on i386 and also add the compat functions
necessary to run 32 bit binaries on x86_64.

Add compat_sys_move_pages to the x86_64 32bit binary layer.  Note that it is
not up to date so I added the missing pieces.  Not sure if this is done the
right way.

[akpm@osdl.org: compile fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
b63d64a324 [PATCH] sys_move_pages: x86_64 support
sys_move_pages support for x86_64

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
742755a1d8 [PATCH] page migration: sys_move_pages(): support moving of individual pages
move_pages() is used to move individual pages of a process. The function can
be used to determine the location of pages and to move them onto the desired
node. move_pages() returns status information for each page.

long move_pages(pid, number_of_pages_to_move,
		addresses_of_pages[],
		nodes[] or NULL,
		status[],
		flags);

The addresses of pages is an array of void * pointing to the
pages to be moved.

The nodes array contains the node numbers that the pages should be moved
to. If a NULL is passed instead of an array then no pages are moved but
the status array is updated. The status request may be used to determine
the page state before issuing another move_pages() to move pages.

The status array will contain the state of all individual page migration
attempts when the function terminates. The status array is only valid if
move_pages() completed successfullly.

Possible page states in status[]:

0..MAX_NUMNODES	The page is now on the indicated node.

-ENOENT		Page is not present

-EACCES		Page is mapped by multiple processes and can only
		be moved if MPOL_MF_MOVE_ALL is specified.

-EPERM		The page has been mlocked by a process/driver and
		cannot be moved.

-EBUSY		Page is busy and cannot be moved. Try again later.

-EFAULT		Invalid address (no VMA or zero page).

-ENOMEM		Unable to allocate memory on target node.

-EIO		Unable to write back page. The page must be written
		back in order to move it since the page is dirty and the
		filesystem does not provide a migration function that
		would allow the moving of dirty pages.

-EINVAL		A dirty page cannot be moved. The filesystem does not provide
		a migration function and has no ability to write back pages.

The flags parameter indicates what types of pages to move:

MPOL_MF_MOVE	Move pages that are only mapped by the process.

MPOL_MF_MOVE_ALL Also move pages that are mapped by multiple processes.
		Requires sufficient capabilities.

Possible return codes from move_pages()

-ENOENT		No pages found that would require moving. All pages
		are either already on the target node, not present, had an
		invalid address or could not be moved because they were
		mapped by multiple processes.

-EINVAL		Flags other than MPOL_MF_MOVE(_ALL) specified or an attempt
		to migrate pages in a kernel thread.

-EPERM		MPOL_MF_MOVE_ALL specified without sufficient priviledges.
		or an attempt to move a process belonging to another user.

-EACCES		One of the target nodes is not allowed by the current cpuset.

-ENODEV		One of the target nodes is not online.

-ESRCH		Process does not exist.

-E2BIG		Too many pages to move.

-ENOMEM		Not enough memory to allocate control array.

-EFAULT		Parameters could not be accessed.

A test program for move_pages() may be found with the patches
on ftp.kernel.org:/pub/linux/kernel/people/christoph/pmig/patches-2.6.17-rc4-mm3

From: Christoph Lameter <clameter@sgi.com>

  Detailed results for sys_move_pages()

  Pass a pointer to an integer to get_new_page() that may be used to
  indicate where the completion status of a migration operation should be
  placed.  This allows sys_move_pags() to report back exactly what happened to
  each page.

  Wish there would be a better way to do this. Looks a bit hacky.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
95a402c384 [PATCH] page migration: use allocator function for migrate_pages()
Instead of passing a list of new pages, pass a function to allocate a new
page.  This allows the correct placement of MPOL_INTERLEAVE pages during page
migration.  It also further simplifies the callers of migrate pages.
migrate_pages() becomes similar to migrate_pages_to() so drop
migrate_pages_to().  The batching of new page allocations becomes unnecessary.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
aaa994b300 [PATCH] page migration: handle freeing of pages in migrate_pages()
Do not leave pages on the lists passed to migrate_pages().  Seems that we will
not need any postprocessing of pages.  This will simplify the handling of
pages by the callers of migrate_pages().

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
e24f0b8f76 [PATCH] page migration: simplify migrate_pages()
Currently migrate_pages() is mess with lots of goto.  Extract two functions
from migrate_pages() and get rid of the gotos.

Plus we can just unconditionally set the locked bit on the new page since we
are the only one holding a reference.  Locking is to stop others from
accessing the page once we establish references to the new page.

Remove the list_del from move_to_lru in order to have finer control over list
processing.

[akpm@osdl.org: add debug check]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Kirill Korotaev
8f9de51a4a [PATCH] printk() should not be called under zone->lock
This patch fixes printk() under zone->lock in show_free_areas().  It can be
unsafe to call printk() under this lock, since caller can try to
allocate/free some memory and selfdeadlock on this lock.  I found
allocations/freeing mem both in netconsole and serial console.

This issue was faced in reallity when meminfo was periodically printed for
debug purposes and netconsole was used.

Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Ralf Baechle
d501e62bc7 [PATCH] Delete unused definitions of kvaddr_to_nid
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Randy Dunlap
485bb99b49 [PATCH] kernel-doc for mm/filemap.c
mm/filemap.c:
- add lots of kernel-doc;
- fix some typos and kernel-doc errors;
- drop some blank lines between function close and EXPORT_SYMBOL();

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Paul Drynoff
800590f523 [PATCH] slab: kmalloc, kzalloc comments cleanup and fix
- Move comments for kmalloc to right place, currently it near __do_kmalloc

- Comments for kzalloc

- More detailed comments for kmalloc

- Appearance of "kmalloc" and "kzalloc" man pages after "make mandocs"

[rdunlap@xenotime.net: simplification]
Signed-off-by: Paul Drynoff <pauldrynoff@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: 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>
2006-06-23 07:42:52 -07:00
KAMEZAWA Hiroyuki
5a4d436159 [PATCH] update vm_total_pages at memory hotadd
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Andrew Morton
bd1e22b8e0 [PATCH] initialise total_memory() earlier
Initialise total_memory earlier in boot.  Because if for some reason we run
page reclaim early in boot, we don't want total_memory to be zero when we use
it as a divisor.

And rename total_memory to vm_total_pages to avoid naming clashes with
architectures.

Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Martin Bligh <mbligh@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Ingo Molnar
e0a4272679 [PATCH] mm/slab.c: fix early init assumption
The SLAB bootstrap code assumes that the first two kmalloc caches created
(the INDEX_AC and INDEX_L3 kmalloc caches) wont be off-slab.  But due to AC
and L3 structure size increase in lockdep, one of them ended up being
off-slab, and subsequently crashing with:

Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP:
 [<ffffffff80267478>] kmem_cache_alloc+0x26/0x7d

The fix is to introduce a bootstrap flag and to use it to prevent off-slab
caches being created so early during bootup.

(The calculation for off-slab caches is quite complex so i didnt want to
complicate things with introducing yet another INDEX_ calculation, the flag
approach is simpler and smaller.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Hugh Dickins
668e0d8f1a [PATCH] fix update_mmu_cache in fremap.c
There are two calls to update_mmu_cache in fremap.c, both defective.
The one in install_page needs to be accompanied by lazy_mmu_prot_update
(some other cleanup time, move that into ia64 update_mmu_cache itself); and
the one in install_file_pte should be removed since the pte is not present.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Hugh Dickins
185606fc6a [PATCH] remove unused o_flags from do_shmat
Remove the unused variable o_flags from do_shmat.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Hugh Dickins
70af7c5c64 [PATCH] swapoff: use atomic_inc_not_zero() on mm_users
Now that we have atomic_inc_not_zero, it's more elegant for try_to_unuse to
use that on mm_users: doesn't actually matter at present, but safer to be
sure that once mm_users has gone to 0, nothing raises it for an instant.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
David Howells
9637a5efd4 [PATCH] add page_mkwrite() vm_operations method
Add a new VMA operation to notify a filesystem or other driver about the
MMU generating a fault because userspace attempted to write to a page
mapped through a read-only PTE.

This facility permits the filesystem or driver to:

 (*) Implement storage allocation/reservation on attempted write, and so to
     deal with problems such as ENOSPC more gracefully (perhaps by generating
     SIGBUS).

 (*) Delay making the page writable until the contents have been written to a
     backing cache. This is useful for NFS/AFS when using FS-Cache/CacheFS.
     It permits the filesystem to have some guarantee about the state of the
     cache.

 (*) Account and limit number of dirty pages. This is one piece of the puzzle
     needed to make shared writable mapping work safely in FUSE.

Needed by cachefs (Or is it cachefiles?  Or fscache? <head spins>).

At least four other groups have stated an interest in it or a desire to use
the functionality it provides: FUSE, OCFS2, NTFS and JFFS2.  Also, things like
EXT3 really ought to use it to deal with the case of shared-writable mmap
encountering ENOSPC before we permit the page to be dirtied.

From: Peter Zijlstra <a.p.zijlstra@chello.nl>

  get_user_pages(.write=1, .force=1) can generate COW hits on read-only
  shared mappings, this patch traps those as mkpage_write candidates and fails
  to handle them the old way.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Joel Becker <Joel.Becker@oracle.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Con Kolivas
bd96b9eb7c [PATCH] mm: fix swap unused warning
If CONFIG_SWAP is not defined we get:

mm/vmscan.c: In function ‘remove_mapping’:
mm/vmscan.c:387: warning: unused variable ‘swap’

Convert defines in swap.h into blank inline functions to fix this warning
and be consistent.

Signed-off-by: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Andy Whitcroft
30c253e6da [PATCH] sparsemem: record nid during memory present
Record the node id as we mark sections for instantiation.  Use this nid
during instantiation to direct allocations.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Mike Kravetz <kravetz@us.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Bob Picco <bob.picco@hp.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Martin Bligh <mbligh@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Pekka Enberg
ddc2e812d5 [PATCH] slab: verify pointers before free
Passing an invalid pointer to kfree() and kmem_cache_free() is likely to
cause bad memory corruption or even take down the whole system because the
bad pointer is likely reused immediately due to the per-CPU caches.  Until
now, we don't do any verification for this if CONFIG_DEBUG_SLAB is
disabled.

As suggested by Linus, add PageSlab check to page_to_cache() and
page_to_slab() to verify pointers passed to kfree().  Also, move the
stronger check from cache_free_debugcheck() to kmem_cache_free() to ensure
the passed pointer actually belongs to the cache we're about to free the
object.

For page_to_cache() and page_to_slab(), the assertions should have
virtually no extra cost (two instructions, no data cache pressure) and for
kmem_cache_free() the overhead should be minimal.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Christoph Lameter
8d3c138b77 [PATCH] page migration: Update documentation
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Christoph Lameter
04e62a29bf [PATCH] More page migration: use migration entries for file pages
This implements the use of migration entries to preserve ptes of file backed
pages during migration.  Processes can therefore be migrated back and forth
without loosing their connection to pagecache pages.

Note that we implement the migration entries only for linear mappings.
Nonlinear mappings still require the unmapping of the ptes for migration.

And another writepage() ugliness shows up.  writepage() can drop the page
lock.  Therefore we have to remove migration ptes before calling writepages()
in order to avoid having migration entries point to unlocked pages.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Christoph Lameter
442c9137de [PATCH] More page migration: do not inc/dec rss counters
If we install a migration entry then the rss not really decreases since the
page is just moved somewhere else.  We can save ourselves the work of
decrementing and later incrementing which will just eventually cause cacheline
bouncing.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Christoph Lameter
6c5240ae7f [PATCH] Swapless page migration: modify core logic
Use the migration entries for page migration

This modifies the migration code to use the new migration entries.  It now
becomes possible to migrate anonymous pages without having to add a swap
entry.

We add a couple of new functions to replace migration entries with the proper
ptes.

We cannot take the tree_lock for migrating anonymous pages anymore.  However,
we know that we hold the only remaining reference to the page when the page
count reaches 1.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
d75a0fcda2 [PATCH] Swapless page migration: rip out swap based logic
Rip the page migration logic out.

Remove all code that has to do with swapping during page migration.

This also guts the ability to migrate pages to swap.  No one used that so lets
let it go for good.

Page migration should be a bit broken after this patch.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
0697212a41 [PATCH] Swapless page migration: add R/W migration entries
Implement read/write migration ptes

We take the upper two swapfiles for the two types of migration ptes and define
a series of macros in swapops.h.

The VM is modified to handle the migration entries.  migration entries can
only be encountered when the page they are pointing to is locked.  This limits
the number of places one has to fix.  We also check in copy_pte_range and in
mprotect_pte_range() for migration ptes.

We check for migration ptes in do_swap_cache and call a function that will
then wait on the page lock.  This allows us to effectively stop all accesses
to apge.

Migration entries are created by try_to_unmap if called for migration and
removed by local functions in migrate.c

From: Hugh Dickins <hugh@veritas.com>

  Several times while testing swapless page migration (I've no NUMA, just
  hacking it up to migrate recklessly while running load), I've hit the
  BUG_ON(!PageLocked(p)) in migration_entry_to_page.

  This comes from an orphaned migration entry, unrelated to the current
  correctly locked migration, but hit by remove_anon_migration_ptes as it
  checks an address in each vma of the anon_vma list.

  Such an orphan may be left behind if an earlier migration raced with fork:
  copy_one_pte can duplicate a migration entry from parent to child, after
  remove_anon_migration_ptes has checked the child vma, but before it has
  removed it from the parent vma.  (If the process were later to fault on this
  orphaned entry, it would hit the same BUG from migration_entry_wait.)

  This could be fixed by locking anon_vma in copy_one_pte, but we'd rather
  not.  There's no such problem with file pages, because vma_prio_tree_add
  adds child vma after parent vma, and the page table locking at each end is
  enough to serialize.  Follow that example with anon_vma: add new vmas to the
  tail instead of the head.

  (There's no corresponding problem when inserting migration entries,
  because a missed pte will leave the page count and mapcount high, which is
  allowed for.  And there's no corresponding problem when migrating via swap,
  because a leftover swap entry will be correctly faulted.  But the swapless
  method has no refcounting of its entries.)

From: Ingo Molnar <mingo@elte.hu>

  pte_unmap_unlock() takes the pte pointer as an argument.

From: Hugh Dickins <hugh@veritas.com>

  Several times while testing swapless page migration, gcc has tried to exec
  a pointer instead of a string: smells like COW mappings are not being
  properly write-protected on fork.

  The protection in copy_one_pte looks very convincing, until at last you
  realize that the second arg to make_migration_entry is a boolean "write",
  and SWP_MIGRATION_READ is 30.

  Anyway, it's better done like in change_pte_range, using
  is_write_migration_entry and make_migration_entry_read.

From: Hugh Dickins <hugh@veritas.com>

  Remove unnecessary obfuscation from sys_swapon's range check on swap type,
  which blew up causing memory corruption once swapless migration made
  MAX_SWAPFILES no longer 2 ^ MAX_SWAPFILES_SHIFT.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
From: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
8351a6e478 [PATCH] page migration cleanup: move fallback handling into special function
Move the fallback code into a new fallback function and make the function
behave like any other migration function.  This requires retaking the lock if
pageout() drops it.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
2d1db3b117 [PATCH] page migration cleanup: pass "mapping" to migration functions
Change handling of address spaces.

Pass a pointer to the address space in which the page is migrated to all
migration function.  This avoids repeatedly having to retrieve the address
space pointer from the page and checking it for validity.  The old page
mapping will change once migration has gone to a certain step, so it is less
confusing to have the pointer always available.

Move the setting of the mapping and index for the new page into
migrate_pages().

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
c3fcf8a5da [PATCH] page migration cleanup: extract try_to_unmap from migration functions
Extract try_to_unmap and rename remove_references -> move_mapping

try_to_unmap() may significantly change the page state by for example setting
the dirty bit.  It is therefore best to unmap in migrate_pages() before
calling any migration functions.

migrate_page_remove_references() will then only move the new page in place of
the old page in the mapping.  Rename the function to
migrate_page_move_mapping().

This allows us to get rid of the special unmapping for the fallback path.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
5b5c7120e2 [PATCH] page migration cleanup: drop nr_refs in remove_references()
Drop nr_refs parameter from migrate_page_remove_references()

The nr_refs parameter is not really useful since the number of remaining
references is always

1 for anonymous pages without a mapping
2 for pages with a mapping
3 for pages with a mapping and PagePrivate set.

Remove the early check for the number of references since we are checking
page_mapcount() earlier.  Ultimately only the refcount matters after the
tree_lock has been obtained.

Signed-off-by: Christoph Lameter <clameter@sgi.coim>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
e7340f7330 [PATCH] page migration cleanup: remove useless definitions
Remove the export for migrate_page_remove_references() and migrate_page_copy()
that are unlikely to be used directly by filesystems implementing migration.
The export was useful when buffer_migrate_page() lived in fs/buffer.c but it
has now been moved to migrate.c in the migration reorg.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00