mm_take_all_locks holds off reclaim from an entire mm_struct. This allows
mmu notifiers to register into the mm at any time with the guarantee that
no mmu operation is in progress on the mm.
This operation locks against the VM for all pte/vma/mm related operations
that could ever happen on a certain mm. This includes vmtruncate,
try_to_unmap, and all page faults.
The caller must take the mmap_sem in write mode before calling
mm_take_all_locks(). The caller isn't allowed to release the mmap_sem
until mm_drop_all_locks() returns.
mmap_sem in write mode is required in order to block all operations that
could modify pagetables and free pages without need of altering the vma
layout (for example populate_range() with nonlinear vmas). It's also
needed in write mode to avoid new anon_vmas to be associated with existing
vmas.
A single task can't take more than one mm_take_all_locks() in a row or it
would deadlock.
mm_take_all_locks() and mm_drop_all_locks are expensive operations that
may have to take thousand of locks.
mm_take_all_locks() can fail if it's interrupted by signals.
When mmu_notifier_register returns, we must be sure that the driver is
notified if some task is in the middle of a vmtruncate for the 'mm' where
the mmu notifier was registered (mmu_notifier_invalidate_range_start/end
is run around the vmtruncation but mmu_notifier_register can run after
mmu_notifier_invalidate_range_start and before
mmu_notifier_invalidate_range_end). Same problem for rmap paths. And
we've to remove page pinning to avoid replicating the tlb_gather logic
inside KVM (and GRU doesn't work well with page pinning regardless of
needing tlb_gather), so without mm_take_all_locks when vmtruncate frees
the page, kvm would have no way to notice that it mapped into sptes a page
that is going into the freelist without a chance of any further
mmu_notifier notification.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Andrea Arcangeli <andrea@qumranet.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kanoj Sarcar <kanojsarcar@yahoo.com>
Cc: Roland Dreier <rdreier@cisco.com>
Cc: Steve Wise <swise@opengridcomputing.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Chris Wright <chrisw@redhat.com>
Cc: Marcelo Tosatti <marcelo@kvack.org>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Izik Eidus <izike@qumranet.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes a merge goof whereby ARCH_EP93XX got the "select HAVE_CLK" line
which belongs instead with ARCH_AT91.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SuSE's insserve initscript ordering program hits kernel BUG at mm/shmem.c:814
on 2.6.26. It's using posix_fadvise on directories, and the shmem_readpage
method added in 2.6.23 is letting POSIX_FADV_WILLNEED allocate useless pages
to a tmpfs directory, incrementing i_blocks count but never decrementing it.
Fix this by assigning shmem_aops (pointing to readpage and writepage and
set_page_dirty) only when it's needed, on a regular file or a long symlink.
Many thanks to Kel for outstanding bugreport and steps to reproduce it.
Reported-by: Kel Modderman <kel@otaku42.de>
Tested-by: Kel Modderman <kel@otaku42.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix compilation errors on avr32 and without CONFIG_SWAP, introduced by
ba92a43dba ("exec: remove some includes")
In file included from include/asm/tlb.h:24,
from fs/exec.c:55:
include/asm-generic/tlb.h: In function 'tlb_flush_mmu':
include/asm-generic/tlb.h:76: error: implicit declaration of function 'release_pages'
include/asm-generic/tlb.h: In function 'tlb_remove_page':
include/asm-generic/tlb.h:105: error: implicit declaration of function 'page_cache_release'
make[1]: *** [fs/exec.o] Error 1
This straightforward part-revert is nobody's favourite patch to address
the underlying tlb.h needs swap.h needs pagemap.h (but sparc won't like
that) mess; but appropriate to fix the build now before any overhaul.
Reported-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Reported-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Tested-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'cpus4096-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
cpu masks: optimize and clean up cpumask_of_cpu()
cpumask: export cpumask_of_cpu_map
cpumask: change cpumask_of_cpu_ptr to use new cpumask_of_cpu
cpumask: put cpumask_of_cpu_map in the initdata section
cpumask: make cpumask_of_cpu_map generic
There's a brown paper bag compile failure introduced by this patch
commit a013869248
Author: David Sterba <dsterba@suse.cz>
Date: Mon Jul 28 16:53:32 2008 +0200
ipwireless: Preallocate received packet buffers with MRU size
Really, it can't ever have been even compile tested. It looks like the
closing bracket is in the wrong place, so this is the fix.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clean up and optimize cpumask_of_cpu(), by sharing all the zero words.
Instead of stupidly generating all possible i=0...NR_CPUS 2^i patterns
creating a huge array of constant bitmasks, realize that the zero words
can be shared.
In other words, on a 64-bit architecture, we only ever need 64 of these
arrays - with a different bit set in one single world (with enough zero
words around it so that we can create any bitmask by just offsetting in
that big array). And then we just put enough zeroes around it that we
can point every single cpumask to be one of those things.
So when we have 4k CPU's, instead of having 4k arrays (of 4k bits each,
with one bit set in each array - 2MB memory total), we have exactly 64
arrays instead, each 8k bits in size (64kB total).
And then we just point cpumask(n) to the right position (which we can
calculate dynamically). Once we have the right arrays, getting
"cpumask(n)" ends up being:
static inline const cpumask_t *get_cpu_mask(unsigned int cpu)
{
const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
p -= cpu / BITS_PER_LONG;
return (const cpumask_t *)p;
}
This brings other advantages and simplifications as well:
- we are not wasting memory that is just filled with a single bit in
various different places
- we don't need all those games to re-create the arrays in some dense
format, because they're already going to be dense enough.
if we compile a kernel for up to 4k CPU's, "wasting" that 64kB of memory
is a non-issue (especially since by doing this "overlapping" trick we
probably get better cache behaviour anyway).
[ mingo@elte.hu:
Converted Linus's mails into a commit. See:
http://lkml.org/lkml/2008/7/27/156http://lkml.org/lkml/2008/7/28/320
Also applied a family filter - which also has the side-effect of leaving
out the bits where Linus calls me an idio... Oh, never mind ;-)
]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
dlm: fix uninitialized variable for search_rsb_list callers
dlm: release socket on error
dlm: fix basts for granted CW waiting PR/CW
dlm: check for null in device_write
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits)
powerpc: Disable 64K hugetlb support when doing 64K SPU mappings
powerpc/powermac: Fixup default serial port device for pmac_zilog
powerpc/powermac: Use sane default baudrate for SCC debugging
powerpc/mm: Implement _PAGE_SPECIAL & pte_special() for 64-bit
powerpc: Show processor cache information in sysfs
powerpc: Make core id information available to userspace
powerpc: Make core sibling information available to userspace
powerpc/vio: More fallout from dma_mapping_error API change
ibmveth: Fix multiple errors with dma_mapping_error conversion
powerpc/pseries: Fix CMO sysdev attribute API change fallout
powerpc: Enable tracehook for the architecture
powerpc: Add TIF_NOTIFY_RESUME support for tracehook
powerpc: Add asm/syscall.h with the tracehook entry points
powerpc: Make syscall tracing use tracehook.h helpers
powerpc: Call tracehook_signal_handler() when setting up signal frames
powerpc: Update cpu_sibling_maps dynamically
powerpc: register_cpu_online should be __cpuinit
powerpc: kill useless SMT code in prom_hold_cpus
powerpc: Fix 8xx build failure
powerpc: Fix vio build warnings
...
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (72 commits)
sh: SuperH Mobile CEU and camera platform data for AP325RXA
sh: Update smc911x platform data for AP325RXA
sh: SuperH Mobile LCDC platform data for AP325RXA
sh: Add SuperH Mobile CEU platform data for Migo-R
sh: Add SuperH Mobile LCDC platform data for Migo-R
sh: Move asid_cache() out of ifdef to fix SH-3/4 nommu build.
sh: Workaround for __put_user_asm() bug with gcc 4.x on big-endian.
sh: Wire up new syscalls.
sh: fix uImage Entry Point
sh_keysc: remove request_mem_region() and release_mem_region()
sh: Don't miss pending signals returning to user mode after signal processing
sh: Use clk_always_enable() on sh7366
sh: Use clk_always_enable() on sh7343 / SE77343
sh: Use clk_always_enable() on sh7722 / Migo-R / SE7722
sh: Use clk_always_enable() on sh7723 / ap325rxa
sh: Introduce clk_always_enable() function
sh: Show all clocks and their state in /proc/clocks
sh: Merge sh7343 and sh7722 clock code
sh: Add SuperH Mobile MSTPCR bits to clock framework
sh: Use arch_flags to simplify sh7722 siu clock code
...
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
net: missing bits of net-namespace / sysctl
ipcomp: Fix warnings after ipcomp consolidation.
dccp: Add check for truncated ICMPv6 DCCP error packets
dccp: Fix incorrect length check for ICMPv4 packets
dccp: Add check for sequence number in ICMPv6 message
dccp: Fix sequence number check for ICMPv4 packets
dccp: Bug-Fix - AWL was never updated
dccp: Allow to distinguish original and retransmitted packets
Add git pull command info and diffstat summary info so that we don't
have to search email archives for it repeatedly.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Noticed because of this warning:
drivers/base/memory.c:279: warning: initialization from incompatible pointer type
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
pm_idle_save resp. pm_idle_old can be NULL when the restore code in
acpi_processor_cst_has_changed() resp. cpuidle_uninstall_idle_handler()
is called. This can set pm_idle unconditinally to NULL, which causes the
kernel to panic when calling pm_idle in the x86 idle code. This was
covered by an extra check for !pm_idle in the x86 idle code, which was
removed during the x86 idle code refactoring.
Instead of restoring the pm_idle check in the x86 code prevent the
acpi/cpuidle code to set pm_idle to NULL.
Reported by: Dhaval Giani http://lkml.org/lkml/2008/7/2/309
Based on a debug patch from Ingo Molnar
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'i2c-for-linus' of git://aeryn.fluff.org.uk/bjdooks/linux:
i2c: Blackfin I2C Driver: Functional power management support
i2c: Documentation: upgrading clients HOWTO
i2c: S3C24XX I2C frequency scaling support.
i2c: i2c_gpio: keep probe resident for hotplugged devices.
i2c: S3C2410: Pass the I2C bus number via drivers platform data
ipwireless: Preallocate received packet buffers with MRU size
Packets are assembled from link size (~300 bytes) up to PPP MRU
(1500 by default). Try to preallocate full size rather than
repeatedly advance buffer size by 256 bytes.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ipwireless: Put packets to pool start
Put packets to pool start, try to reuse cached memory.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ipwireless: Increase PPP outgoing queue size
Increase default size of PPP outgoing queue. Currently set to 1, which
means that a packet quickly following another pushed by PPP must wait
until hardware actually sends the previous and PPP has to be waken up
by ppp_wakeup(). This slows down upstream.
Now PPP can push more packets at once which get buffered inside driver
and pushed immediatelly to hardware when previous packet is out.
Experiments show that size = 10 is quite good for all connection types
(GPRS/EDGE/UMTS) and gains 4 KB/sec of upload for UMTS for batch uploads.
Need for higher queue size than 10 occures in only < 0.1 % of cases.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ipwireless: Explicitly request io and mem regions
Documentation/pcmcia/driver-changes.txt says, that driver should call request_region
for used memory/io regions since PCMCIA does not do this (since 2.6.8).
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ipwireless: Do not return value from sending funcs
Do not return value from do_send_fragment and do_send_packet, it's not used.
The packet size checks are not useful too:
* zero length packet will never be sent, caller always passes packet_header
size which is either 1 or 3
* MTU check is done in caller, no need to repeat
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ipwireless: Misc cleanups
- remove likely() and some extra () in ifs
- use unsigned in for loops
- remove useless typecasts
- remove obvious comments
- add () around ?:
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PM_SUSPEND_MEM: Blackfin does not maintain register state through
Hibernate. Save and restore peripheral base initialization during
PM transitions.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Add a document describing how i2c clients on Linux 2.6 can be
moved from the old to the new driver model.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Change the i2c_gpio driver to use platform_driver_register()
instead of platform_driver_probe() to ensure that is can
attach to any devices that may be loaded after it has initialised.
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Allow the platform data to specify the bus bumber that the
new I2C bus will be given. This is to allow the use of the
board registration mechanism to specify the new style of
I2C device registration which allows boards to provide a
list of attached devices.
Note, as discussed on the mailing list, we have dropped
backwards compatibility of adding an dynamic bus number
as it should not affect most boards to have the bus pinned
to 0 if they have either not specified platform data for
driver. Any board supplying platform data will automatically
have the bus_num field set to 0, and anyone who needs the
driver on a different bus number can supply platform data
to set bus_num.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Please pull from git://git.kernel.org/pub/scm/linux/kernel/git/kkeil/ISDN-2.6.git master
This was a forgotten item in a printk from the old driver,
the DMA allocation use already the new interface.
Signed-off-by: Karsten Keil <kkeil@suse.de>
Add AP325RXA specific platform data for on-chip sh7723 CEU and ncm03j camera.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Pass board specific smc911x parameters using struct smc911x_platdata.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add Migo-R specific platform data for on-chip sh7722 CEU and ov772x camera.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
