This makes NFS follow the standard generic_file_llseek locking scheme.
Cc: Trond.Myklebust@netapp.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This gives ext4 the benefits of unlocked llseek.
Cc: tytso@mit.edu
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a generic_file_llseek variant to the VFS that allows passing in
the maximum file size of the file system, instead of always
using maxbytes from the superblock.
This can be used to eliminate some cut'n'paste seek code in ext4.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The i_mutex lock use of generic _file_llseek hurts. Independent processes
accessing the same file synchronize over a single lock, even though
they have no need for synchronization at all.
Under high utilization this can cause llseek to scale very poorly on larger
systems.
This patch does some rethinking of the llseek locking model:
First the 64bit f_pos is not necessarily atomic without locks
on 32bit systems. This can already cause races with read() today.
This was discussed on linux-kernel in the past and deemed acceptable.
The patch does not change that.
Let's look at the different seek variants:
SEEK_SET: Doesn't really need any locking.
If there's a race one writer wins, the other loses.
For 32bit the non atomic update races against read()
stay the same. Without a lock they can also happen
against write() now. The read() race was deemed
acceptable in past discussions, and I think if it's
ok for read it's ok for write too.
=> Don't need a lock.
SEEK_END: This behaves like SEEK_SET plus it reads
the maximum size too. Reading the maximum size would have the
32bit atomic problem. But luckily we already have a way to read
the maximum size without locking (i_size_read), so we
can just use that instead.
Without i_mutex there is no synchronization with write() anymore,
however since the write() update is atomic on 64bit it just behaves
like another racy SEEK_SET. On non atomic 32bit it's the same
as SEEK_SET.
=> Don't need a lock, but need to use i_size_read()
SEEK_CUR: This has a read-modify-write race window
on the same file. One could argue that any application
doing unsynchronized seeks on the same file is already broken.
But for the sake of not adding a regression here I'm
using the file->f_lock to synchronize this. Using this
lock is much better than the inode mutex because it doesn't
synchronize between processes.
=> So still need a lock, but can use a f_lock.
This patch implements this new scheme in generic_file_llseek.
I dropped generic_file_llseek_unlocked and changed all callers.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This doesn't change anything for the compiler, but hch thought it would
make the code clearer.
I moved the reference counting into its own little inline.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add inlines to all the submission path functions. While this increases
code size it also gives gcc a lot of optimization opportunities
in this critical hotpath.
In particular -- together with some other changes -- this
allows gcc to get rid of the unnecessary clearing of
sdio at the beginning and optimize the messy parameter passing.
Any non inlining of a function which takes a sdio parameter
would break this optimization because they cannot be done if the
address of a structure is taken.
Note that benefits are only seen with CONFIG_OPTIMIZE_INLINING
and CONFIG_CC_OPTIMIZE_FOR_SIZE both set to off.
This gives about 2.2% improvement on a large database benchmark
with a high IOPS rate.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Only a single b_private field in the map_bh buffer head is needed after
the submission path. Move map_bh separately to avoid storing
this information in the long term slab.
This avoids the weird 104 byte hole in struct dio_submit which also needed
to be memseted early.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
A direct slab call is slightly faster than kmalloc and can be better cached
per CPU. It also avoids rounding to the next kmalloc slab.
In addition this enforces cache line alignment for struct dio to avoid
any false sharing.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Fix most problems reported by pahole.
There is still a weird 104 byte hole after map_bh. I'm not sure what
causes this.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
There's nothing on the stack, even before my changes.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This large, but largely mechanic, patch moves all fields in struct dio
that are only used in the submission path into a separate on stack
data structure. This has the advantage that the memory is very likely
cache hot, which is not guaranteed for memory fresh out of kmalloc.
This also gives gcc more optimization potential because it can easier
determine that there are no external aliases for these variables.
The sdio initialization is a initialization now instead of memset.
This allows gcc to break sdio into individual fields and optimize
away unnecessary zeroing (after all the functions are inlined)
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
We need to move the inode to the end of the list to actually make the
spinning prevention explained in the comment above it work. With a
plain list_move it will simply stay in place as we're always reclaiming
from the head of the list.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruen@kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruen@kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
We are going to add more flags and having them in hex format
make it simpler
Acked-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruen@kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This was found by inspection while tracking a similar
bug in compat_statfs64, that has been fixed in mainline
since decemeber.
- This fixes a bug where not all of the f_spare fields
were cleared on mips and s390.
- Add the f_flags field to struct compat_statfs
- Copy f_flags to userspace in case someone cares.
- Use __clear_user to copy the f_spare field to userspace
to ensure that all of the elements of f_spare are cleared.
On some architectures f_spare is has 5 ints and on some
architectures f_spare only has 4 ints. Which makes
the previous technique of clearing each int individually
broken.
I don't expect anyone actually uses the old statfs system
call anymore but if they do let them benefit from having
the compat and the native version working the same.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
nfsiostat was failing to find mounted filesystems on kernels after
2.6.38 because of changes to show_vfsstat() by commit
c7f404b40a. This patch adds back the
"device" tag before the nfs server entry so scripts can parse the
mountstats file correctly.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
CC: stable@kernel.org [>=2.6.39]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Currently, when you call iov_iter_advance, then the pointer to the iovec
array can be incremented, but it does not decrement the nr_segs value in
the iov_iter struct. The result is a iov_iter struct with a nr_segs
value that goes beyond the end of the array.
While I'm not aware of anything that's specifically broken by this, it
seems odd and a bit dangerous not to decrement that value. If someone
were to trust the nr_segs value to be correct, then they could end up
walking off the end of the array.
Changing this might also provide some micro-optimization when dealing
with the last iovec in an array. Many of the other routines that deal
with iov_iter have optimized codepaths when nr_segs == 1.
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
* git://git.infradead.org/iommu-2.6:
intel-iommu: fix superpage support in pfn_to_dma_pte()
intel-iommu: set iommu_superpage on VM domains to lowest common denominator
intel-iommu: fix return value of iommu_unmap() API
MAINTAINERS: Update VT-d entry for drivers/pci -> drivers/iommu move
intel-iommu: Export a flag indicating that the IOMMU is used for iGFX.
intel-iommu: Workaround IOTLB hang on Ironlake GPU
intel-iommu: Fix AB-BA lockdep report
Commit 4b239f458 ("x86-64, mm: Put early page table high") causes a S4
regression since 2.6.39, namely the machine reboots occasionally at S4
resume. It doesn't happen always, overall rate is about 1/20. But,
like other bugs, once when this happens, it continues to happen.
This patch fixes the problem by essentially reverting the memory
assignment in the older way.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Yinghai Lu <yinghai.lu@oracle.com>
[ We'll hopefully find the real fix, but that's too late for 3.1 now ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix memory leak introduced by commit a6e50b409d
(dm snapshot: skip reading origin when overwriting complete chunk).
When allocating a set of jobs from kc->job_pool, job->master_job must be
set (to point to itself) so that the mempool item gets freed when the
master_job completes.
master_job was introduced by commit c6ea41fbbe
(dm kcopyd: preallocate sub jobs to avoid deadlock)
Reported-by: Michael Leun <ml@newton.leun.net>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
v2:
- register_syscore_ops(&s3c24xx_irq_syscore_ops) does not need to be
conditionally compiled out, it is already optimized out on !CONFIG_PM
- fix also s3c2412 and s3c2416 affected by the same build issue
v1:
s3c2440.c fails to build if !CONFIG_PM because in such case
s3c2410_pm_syscore_ops is not defined. Same error should happen also
in s3c2410.c and s3c2442.c
Signed-off-by: Domenico Andreoli <cavokz@gmail.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Offsets of the irq controller registers were calculated
correctly only for first GPIO bank. This patch fixes
calculation of the register offsets for all GPIO banks.
Reported-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
fib_rules: fix unresolved_rules counting
r8169: fix wrong eee setting for rlt8111evl
r8169: fix driver shutdown WoL regression.
ehea: Change maintainer to me
pptp: pptp_rcv_core() misses pskb_may_pull() call
tproxy: copy transparent flag when creating a time wait
pptp: fix skb leak in pptp_xmit()
bonding: use local function pointer of bond->recv_probe in bond_handle_frame
smsc911x: Add support for SMSC LAN89218
tg3: negate USE_PHYLIB flag check
netconsole: enable netconsole can make net_device refcnt incorrent
bluetooth: Properly clone LSM attributes to newly created child connections
l2tp: fix a potential skb leak in l2tp_xmit_skb()
bridge: fix hang on removal of bridge via netlink
x25: Prevent skb overreads when checking call user data
x25: Handle undersized/fragmented skbs
x25: Validate incoming call user data lengths
udplite: fast-path computation of checksum coverage
IPVS netns shutdown/startup dead-lock
netfilter: nf_conntrack: fix event flooding in GRE protocol tracker
Since 8-bit temperature values are now handled in 16-bit struct
members, values have to be cast to s8 for negative temperatures to be
properly handled. This is broken since kernel version 2.6.39
(commit bce26c58df86599c9570cee83eac58bdaae760e4.)
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: stable@kernel.org # 2.6.39+
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
I don't usually pay much attention to the stale "? " addresses in
stack backtraces, but this lucky report from Pawel Sikora hints that
mremap's move_ptes() has inadequate locking against page migration.
3.0 BUG_ON(!PageLocked(p)) in migration_entry_to_page():
kernel BUG at include/linux/swapops.h:105!
RIP: 0010:[<ffffffff81127b76>] [<ffffffff81127b76>]
migration_entry_wait+0x156/0x160
[<ffffffff811016a1>] handle_pte_fault+0xae1/0xaf0
[<ffffffff810feee2>] ? __pte_alloc+0x42/0x120
[<ffffffff8112c26b>] ? do_huge_pmd_anonymous_page+0xab/0x310
[<ffffffff81102a31>] handle_mm_fault+0x181/0x310
[<ffffffff81106097>] ? vma_adjust+0x537/0x570
[<ffffffff81424bed>] do_page_fault+0x11d/0x4e0
[<ffffffff81109a05>] ? do_mremap+0x2d5/0x570
[<ffffffff81421d5f>] page_fault+0x1f/0x30
mremap's down_write of mmap_sem, together with i_mmap_mutex or lock,
and pagetable locks, were good enough before page migration (with its
requirement that every migration entry be found) came in, and enough
while migration always held mmap_sem; but not enough nowadays, when
there's memory hotremove and compaction.
The danger is that move_ptes() lets a migration entry dodge around
behind remove_migration_pte()'s back, so it's in the old location when
looking at the new, then in the new location when looking at the old.
Either mremap's move_ptes() must additionally take anon_vma lock(), or
migration's remove_migration_pte() must stop peeking for is_swap_entry()
before it takes pagetable lock.
Consensus chooses the latter: we prefer to add overhead to migration
than to mremapping, which gets used by JVMs and by exec stack setup.
Reported-and-tested-by: Paweł Sikora <pluto@agmk.net>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently no type of alignment is specified for PCI expansion roms while
parsing the openfirmware tree. This causes calls to pci_map_rom() to fail.
IORESOURCE_SIZEALIGN is the default alignment used for rom resouces in
pci/probe.c, and has been verified to work with various cards on a ultra 10.
Signed-off-By: Kjetil Oftedal <oftedal@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
we should decrease ops->unresolved_rules when deleting a unresolved rule.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Correct the wrong parameter for setting EEE for RTL8111E-VL.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Due to commit 92fc43b415 ("r8169: modify the
flow of the hw reset."), rtl8169_hw_reset stomps during driver shutdown on
RxConfig bits which are needed for WOL on some versions of the hardware.
As these bits were formerly set from the r81{0x, 68}_pll_power_down methods,
factor them out for use in the driver shutdown (rtl_shutdown) handler.
I favored __rtl8169_get_wol() -hardware state indication- over
RTL_FEATURE_WOL as the latter has become a good candidate for removal.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Hayes <hayeswang@realtek.com>
Tested-by: Marc Ballarin <ballarin.marc@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Breno Leitao has passed the maintainership to me.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Cc: Breno Leitao <leitao@linux.vnet.ibm.com>
Acked-by: Breno Leitão <leitao@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/radeon/kms/atom: fix handling of FB scratch indices
drm/radeon/kms/DCE4.1: fix Select_CrtcSource EncodeMode setting for DP bridges (v2)
drm/radeon/kms/DCE4.1: ss is not supported on the internal pplls
drm/radeon/kms/DCE4.1: fix dig encoder to transmitter mapping
ttm: Fix error-path using an uninitialized value
The change in 8280b66 does not cover the case when v4l2_dev is already
NULL, fix that.
With a Kinect sensor, seen as an USB camera using GSPCA in this context,
a NULL pointer dereference BUG can be triggered by just unplugging the
device after the camera driver has been loaded.
Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
If target_level == 0, current code breaks out of the while-loop if
SUPERPAGE bit is set. We should also break out if PTE is not present.
If we don't do this, KVM calls to iommu_iova_to_phys() will cause
pfn_to_dma_pte() to create mapping for 4KiB pages.
Signed-off-by: Allen Kay <allen.m.kay@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
set dmar->iommu_superpage field to the smallest common denominator
of super page sizes supported by all active VT-d engines. Initialize
this field in intel_iommu_domain_init() API so intel_iommu_map() API
will be able to use iommu_superpage field to determine the appropriate
super page size to use.
Signed-off-by: Allen Kay <allen.m.kay@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
iommu_unmap() API expects IOMMU drivers to return the actual page order
of the address being unmapped. Previous code was just returning page
order passed in from the caller. This patch fixes this problem.
Signed-off-by: Allen Kay <allen.m.kay@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Commit 166e9278a3 ("x86/ia64: intel-iommu: move to drivers/iommu/")
moved the VT-d driver to drivers/iommu, but left the "F:" line in
MAINTAINERS pointing to drivers/pci, which breaks scripts/get_maintainer.pl.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
FB scratch indices are dword indices, but we were treating
them as byte indices. As such, we were getting the wrong
FB scratch data for non-0 indices. Fix the indices and
guard the indexing against indices larger than the scratch
allocation.
Fixes memory corruption on some boards if data was written
past the end of the FB scratch array.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reported-by: Dave Airlie <airlied@redhat.com>
Tested-by: Dave Airlie <airlied@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
e1000e uses paged frags, so any layer incorrectly pulling bytes from skb
can trigger a BUG in skb_pull()
[951.142737] [<ffffffff813d2f36>] skb_pull+0x15/0x17
[951.142737] [<ffffffffa0286824>] pptp_rcv_core+0x126/0x19a [pptp]
[951.152725] [<ffffffff813d17c4>] sk_receive_skb+0x69/0x105
[951.163558] [<ffffffffa0286993>] pptp_rcv+0xc8/0xdc [pptp]
[951.165092] [<ffffffffa02800a3>] gre_rcv+0x62/0x75 [gre]
[951.165092] [<ffffffff81410784>] ip_local_deliver_finish+0x150/0x1c1
[951.177599] [<ffffffff81410634>] ? ip_local_deliver_finish+0x0/0x1c1
[951.177599] [<ffffffff81410846>] NF_HOOK.clone.7+0x51/0x58
[951.177599] [<ffffffff81410996>] ip_local_deliver+0x51/0x55
[951.177599] [<ffffffff814105b9>] ip_rcv_finish+0x31a/0x33e
[951.177599] [<ffffffff8141029f>] ? ip_rcv_finish+0x0/0x33e
[951.204898] [<ffffffff81410846>] NF_HOOK.clone.7+0x51/0x58
[951.214651] [<ffffffff81410bb5>] ip_rcv+0x21b/0x246
pptp_rcv_core() is a nice example of a function assuming everything it
needs is available in skb head.
Reported-by: Bradley Peterson <despite@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
