Commit Graph

110282 Commits

Author SHA1 Message Date
Theodore Ts'o
c2ea3fde61 ext4: Remove old legacy block allocator
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-10 09:40:52 -04:00
Theodore Ts'o
240799cdf2 ext4: Use readahead when reading an inode from the inode table
With modern hard drives, reading 64k takes roughly the same time as
reading a 4k block.  So request readahead for adjacent inode table
blocks to reduce the time it takes when iterating over directories
(especially when doing this in htree sort order) in a cold cache case.
With this patch, the time it takes to run "git status" on a kernel
tree after flushing the caches via "echo 3 > /proc/sys/vm/drop_caches"
is reduced by 21%.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-09 23:53:47 -04:00
Theodore Ts'o
37515facd0 ext4: Improve the documentation for ext4's /proc tunables
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alex Tomas <bzzz@sun.com>
Cc: Andreas Dilger <adilger@sun.com>
2008-10-09 23:21:54 -04:00
Theodore Ts'o
5e8814f2f7 ext4: Combine proc file handling into a single set of functions
Previously mballoc created a separate set of functions for each proc
file.  This combines the tunables into a single set of functions which
gets used for all of the per-superblock proc files, saving
approximately 2k of compiled object code.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-23 18:07:35 -04:00
Theodore Ts'o
9f6200bbfc ext4: move /proc setup and teardown out of mballoc.c
...and into the core setup/teardown code in fs/ext4/super.c so that
other parts of ext4 can define tuning parameters.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-23 09:18:24 -04:00
Theodore Ts'o
f702ba0fd7 ext4: Don't use 'struct dentry' for internal lookups
This is a port of a patch from Linus which fixes a 200+ byte stack
usage problem in ext4_get_parent().

It's more efficient to pass down only the actual parts of the dentry
that matter: the parent inode and the name, instead of allocating a
struct dentry on the stack.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-22 15:21:01 -04:00
Theodore Ts'o
914258bf2c ext4/jbd2: Avoid WARN() messages when failing to write to the superblock
This fixes some very common warnings reported by kerneloops.org

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-06 21:35:40 -04:00
Eric Sandeen
730c213c79 ext4: use percpu data structures for lg_prealloc_list
lg_prealloc_list seems to cry out for a per-cpu data structure; on a large
smp system I think this should be better.  I've lightly tested this change
on a 4-cpu system.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-13 15:23:29 -04:00
Theodore Ts'o
8eea80d52b ext4: Renumber EXT4_IOC_MIGRATE
Pick an ioctl number for EXT4_IOC_MIGRATE that won't conflict with
other ext4 ioctl's.  Since there haven't been any major userspace
users of this ioctl, we can afford to change this now, to avoid
potential problems later.

Also, reorder the ioctl numbers in ext4.h to avoid this sort of
mistake in the future.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-13 19:54:35 -04:00
Aneesh Kumar K.V
4db46fc266 ext4: hook the ext3 migration interface to the EXT4_IOC_SETFLAGS ioctl
This patch hooks the ext3 to ext4 migrate interface to
EXT4_IOC_SETFLAGS ioctl. The userspace interface is via chattr +e.  We
only allow setting extent flags.  Clearing extent flag (migrating from
ext4 to ext3) is not supported.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-08 23:34:06 -04:00
Aneesh Kumar K.V
2a43a87800 ext4: elevate write count for migrate ioctl
The migrate ioctl writes to the filsystem, so we need to elevate the
write count.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-13 12:52:26 -04:00
Li Zefan
7ee1ec4ca3 ext4: add missing unlock in ext4_check_descriptors() on error path
If there group descriptors are corrupted we need unlock the block
group lock before returning from the function; else we will oops when
freeing a spinlock which is still being held.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 10:47:19 -04:00
Theodore Ts'o
05496769e5 jbd2: clean up how the journal device name is printed
Calculate the journal device name once and stash it away in the
journal_s structure.  This avoids needing to call bdevname()
everywhere and reduces stack usage by not needing to allocate an
on-stack buffer.  In addition, we eliminate the '/' that can appear in
device names (e.g. "cciss/c0d0p9" --- see kernel bugzilla #11321) that
can cause problems when creating proc directory names, and include the
inode number to support ocfs2 which creates multiple journals with
different inode numbers.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-16 14:36:17 -04:00
Alexey Dobriyan
899fc1a4cf ext4: fix #11321: create /proc/ext4/*/stats more carefully
ext4 creates per-suberblock directory in /proc/ext4/ . Name used as
basis is taken from bdevname, which, surprise, can contain slash.

However, proc while allowing to use proc_create("a/b", parent) form of
PDE creation, assumes that parent/a was already created.

bdevname in question is 'cciss/c0d0p9', directory is not created and all
this stuff goes directly into /proc (which is real bug).

Warning comes when _second_ partition is mounted.

http://bugzilla.kernel.org/show_bug.cgi?id=11321

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-14 10:21:33 -04:00
Frederic Bohe
c62a11fd95 Update flex_bg free blocks and free inodes counters when resizing.
This fixes a bug which prevented the newly created inodes after a
resize from being used on filesystems with flex_bg.

Signed-off-by: Frederic Bohe <frederic.bohe@bull.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 10:20:24 -04:00
Eric Sandeen
9d9f177572 ext4: Avoid printk floods in the face of directory corruption
Note: some people thinks this represents a security bug, since it
might make the system go away while it is printing a large number of
console messages, especially if a serial console is involved.  Hence,
it has been assigned CVE-2008-3528, but it requires that the attacker
either has physical access to your machine to insert a USB disk with a
corrupted filesystem image (at which point why not just hit the power
button), or is otherwise able to convince the system administrator to
mount an arbitrary filesystem image (at which point why not just
include a setuid shell or world-writable hard disk device file or some
such).  Me, I think they're just being silly. --tytso

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-ext4@vger.kernel.org
Cc: Eugene Teo <eugeneteo@kernel.sg>
2008-10-09 11:15:52 -04:00
Aneesh Kumar K.V
cf17fea657 ext4: Properly update i_disksize.
With delayed allocation we use i_data_sem to update i_disksize.  We need
to update i_disksize only if the new size specified is greater than the
current value and we need to make sure we don't race with other
i_disksize update.  With delayed allocation we will switch to the
write_begin function for non-delayed allocation if we are low on free
blocks.  This means the write_begin function for non-delayed allocation
also needs to use the same locking.

We also need to check and update i_disksize even if the new size is less
that inode.i_size because of delayed allocation.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-13 13:06:18 -04:00
Aneesh Kumar K.V
ae4d537211 ext4: truncate block allocated on a failed ext4_write_begin
For blocksize < pagesize we need to remove blocks that got allocated in
block_write_begin() if we fail with ENOSPC for later blocks.
block_write_begin() internally does this if it allocated pages locally.
This makes sure we don't have blocks outside inode.i_size during ENOSPC.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-13 13:10:25 -04:00
Aneesh Kumar K.V
df22291ff0 ext4: Retry block allocation if we have free blocks left
When we truncate files, the meta-data blocks released are not reused
untill we commit the truncate transaction.  That means delayed get_block
request will return ENOSPC even if we have free blocks left.  Force a
journal commit and retry block allocation if we get ENOSPC with free
blocks left.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 23:05:34 -04:00
Aneesh Kumar K.V
166348dd37 ext4: Don't add the inode to journal handle until after the block is allocated
Make sure we don't add the inode to the journal handle until after the
block allocation, so that a journal commit will not include the inode in
case of block allocation failure.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 23:08:40 -04:00
Aneesh Kumar K.V
68629f29c6 ext4: Fix ext4 nomballoc allocator for ENOSPC
We run into ENOSPC error on nonmballoc ext4, even when there is free blocks
on the filesystem.

The patch includes two changes:

a) Set reservation to NULL if we trying to allocate near group_target_block
from the goal group if the free block in the group is less than windows.
This should give us a better chance to allocate near group_target_block.
This also ensures that if we are not allocating near group_target_block
then we don't trun off reservation. This should enable us to allocate
with reservation from other groups that have large free blocks count.

b) we don't need to check the window size if the block reservation is off.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 23:09:17 -04:00
Aneesh Kumar K.V
5c79161689 ext4: Signed arithmetic fix
This patch converts some usage of ext4_fsblk_t to s64.  This is needed
so that some of the sign conversion works as expected in if loops.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-08 23:12:24 -04:00
Aneesh Kumar K.V
79f0be8d2e ext4: Switch to non delalloc mode when we are low on free blocks count.
The delayed allocation code allocates blocks during writepages(), which
can not handle block allocation failures.  To deal with this, we switch
away from delayed allocation mode when we are running low on free
blocks.  This also allows us to avoid needing to reserve a large number
of meta-data blocks in case all of the requested blocks are
discontiguous.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-08 23:13:30 -04:00
Aneesh Kumar K.V
6bc6e63fcd ext4: Add percpu dirty block accounting.
This patch adds dirty block accounting using percpu_counters.  Delayed
allocation block reservation is now done by updating dirty block
counter.  In a later patch we switch to non delalloc mode if the
filesystem free blocks is greater than 150% of total filesystem dirty
blocks

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao<cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-10 09:39:00 -04:00
Aneesh Kumar K.V
030ba6bc67 ext4: Retry block reservation
During block reservation if we don't have enough blocks left, retry
block reservation with smaller block counts.  This makes sure we try
fallocate and DIO with smaller request size and don't fail early.  The
delayed allocation reservation cannot try with smaller block count. So
retry block reservation to handle temporary disk full conditions.  Also
print free blocks details if we fail block allocation during writepages.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 23:14:50 -04:00
Aneesh Kumar K.V
a30d542a00 ext4: Make sure all the block allocation paths reserve blocks
With delayed allocation we need to make sure block are reserved before
we attempt to allocate them. Otherwise we get block allocation failure
(ENOSPC) during writepages which cannot be handled. This would mean
silent data loss (We do a printk stating data will be lost). This patch
updates the DIO and fallocate code path to do block reservation before
block allocation. This is needed to make sure parallel DIO and fallocate
request doesn't take block out of delayed reserve space.

When free blocks count go below a threshold we switch to a slow patch
which looks at other CPU's accumulated percpu counter values.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-09 10:56:23 -04:00
Aneesh Kumar K.V
c4a0c46ec9 ext4: invalidate pages if delalloc block allocation fails.
We are a bit agressive in invalidating all the pages. But
it is ok because we really don't know why the block allocation
failed and it is better to come of the writeback path
so that user can look for more info.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2008-08-19 21:08:18 -04:00
Theodore Ts'o
af5bc92dde ext4: Fix whitespace checkpatch warnings/errors
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 22:25:24 -04:00
Theodore Ts'o
e5f8eab885 ext4: Fix long long checkpatch warnings
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 22:25:04 -04:00
Theodore Ts'o
4776004f54 ext4: Add printk priority levels to clean up checkpatch warnings
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 23:00:52 -04:00
Mingming Cao
1f7c14c62c percpu counter: clean up percpu_counter_sum_and_set()
percpu_counter_sum_and_set() and percpu_counter_sum() is the same except
the former updates the global counter after accounting.  Since we are
taking the fbc->lock to calculate the precise value of the counter in
percpu_counter_sum() anyway, it should simply set fbc->count too, as the
percpu_counter_sum_and_set() does.

This patch merges these two interfaces into one.
 
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-09 12:50:59 -04:00
Linus Torvalds
3fa8749e58 Linux 2.6.27 2008-10-09 15:13:53 -07:00
Linus Torvalds
efc968d450 Don't allow splice() to files opened with O_APPEND
This is debatable, but while we're debating it, let's disallow the
combination of splice and an O_APPEND destination.

It's not entirely clear what the semantics of O_APPEND should be, and
POSIX apparently expects pwrite() to ignore O_APPEND, for example.  So
we could make up any semantics we want, including the old ones.

But Miklos convinced me that we should at least give it some thought,
and that accepting writes at arbitrary offsets is wrong at least for
IS_APPEND() files (which always have O_APPEND set, even if the reverse
isn't true: you can obviously have O_APPEND set on a regular file).

So disallow O_APPEND entirely for now.  I doubt anybody cares, and this
way we have one less gray area to worry about.

Reported-and-argued-for-by: Miklos Szeredi <miklos@szeredi.hu>
Acked-by: Jens Axboe <ens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-09 14:26:38 -07:00
Linus Torvalds
07f4055418 Merge branch 'hwmon-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6
* 'hwmon-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
  hwmon: (abituguru3) Enable DMI probing feature on Abit AT8 32X
  hwmon: (abituguru3) Enable reading from AUX3 fan on Abit AT8 32X
  hwmon: (adt7473) Fix some bogosity in documentation file
  hwmon: Define sysfs interface for energy consumption register
  hwmon: (it87) Prevent power-off on Shuttle SN68PT
  eeepc-laptop: Fix hwmon interface
2008-10-09 12:23:54 -07:00
Linus Torvalds
9283dfed51 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] correct broken links and email addresses
2008-10-09 12:23:35 -07:00
Matt Mackall
70096a561d SLOB: fix bogus ksize calculation fix
This fixes the previous fix, which was completely wrong on closer
inspection. This version has been manually tested with a user-space
test harness and generates sane values. A nearly identical patch has
been boot-tested.

The problem arose from changing how kmalloc/kfree handled alignment
padding without updating ksize to match. This brings it in sync.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-09 12:18:27 -07:00
Németh Márton
8d59225720 [CPUFREQ] correct broken links and email addresses
Replace the no longer working links and email address in the
documentation and in source code.

Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:40 -04:00
Alistair John Strachan
5e5cddbc3f hwmon: (abituguru3) Enable DMI probing feature on Abit AT8 32X
Enable driver checking of the DMI product name (when enabled) on
an Abit AT8 32X, instead of falling back to a manual probe. This
eliminates false negatives and eventually will help avoid
unnecessary bus probes on unsupported mainboards.

Signed-off-by: Alistair John Strachan <alistair@devzero.co.uk>
Tested-by: Daniel Exner <dex@dragonslave.de>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-10-09 15:33:59 +02:00
Alistair John Strachan
8748a71e8c hwmon: (abituguru3) Enable reading from AUX3 fan on Abit AT8 32X
The table for the Abit AT8 32X was incorrectly missing an entry
for the sixth ("AUX3") fan. Add this entry, exporting the fan
reading to userspace.

Closes lm-sensors.org ticket #2339.

Signed-off-by: Alistair John Strachan <alistair@devzero.co.uk>
Tested-by: Daniel Exner <dex@dragonslave.de>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-10-09 15:33:59 +02:00
Darrick J. Wong
c73c556c1a hwmon: (adt7473) Fix some bogosity in documentation file
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-10-09 15:33:58 +02:00
Darrick J. Wong
ddedc658fc hwmon: Define sysfs interface for energy consumption register
Describe the sysfs files that were introduced in the ibmaem driver.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-10-09 15:33:58 +02:00
Jean Delvare
98dd22c3e0 hwmon: (it87) Prevent power-off on Shuttle SN68PT
On the Shuttle SN68PT, FAN_CTL2 is apparently not connected to a fan,
but to something else. One user has reported instant system power-off
when changing the PWM2 duty cycle, so we disable it.

I use the board name string as the trigger in case the same board is
ever used in other systems.

This closes lm-sensors ticket #2349:
pwmconfig causes a hard poweroff
http://www.lm-sensors.org/ticket/2349

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-10-09 15:33:58 +02:00
Corentin Chary
04dcd84bc7 eeepc-laptop: Fix hwmon interface
Creates a name file in the sysfs directory, that
is needed for the libsensors library to work.
Also rename fan1_pwm to pwm1 and scale its value as needed.

This fixes bug #11520:
http://bugzilla.kernel.org/show_bug.cgi?id=11520

Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-10-09 15:33:57 +02:00
Linus Torvalds
69849375d6 Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  [MIPS] Sibyte: Register PIO PATA device only for Swarm and Litte Sur
2008-10-08 11:41:10 -07:00
Linus Torvalds
392eaef2e9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  tcp: Fix tcp_hybla zero congestion window growth with small rho and large cwnd.
  net: Fix netdev_run_todo dead-lock
  tcp: Fix possible double-ack w/ user dma
  net: only invoke dev->change_rx_flags when device is UP
  netrom: Fix sock_orphan() use in nr_release
  ax25: Quick fix for making sure unaccepted sockets get destroyed.
  Revert "ax25: Fix std timer socket destroy handling."
  [Bluetooth] Add reset quirk for A-Link BlueUSB21 dongle
  [Bluetooth] Add reset quirk for new Targus and Belkin dongles
  [Bluetooth] Fix double frees on error paths of btusb and bpa10x drivers
2008-10-08 11:40:19 -07:00
Ralf Baechle
8806048878 [MIPS] Sibyte: Register PIO PATA device only for Swarm and Litte Sur
Symbol name spaghetti which is too complicated to cleanup on this stage
of the release cycle breaks the build on BCM1480 platforms.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-10-08 19:19:28 +01:00
Daniele Lacamera
9d2c27e17b tcp: Fix tcp_hybla zero congestion window growth with small rho and large cwnd.
Because of rounding, in certain conditions, i.e. when in congestion
avoidance state rho is smaller than 1/128 of the current cwnd, TCP
Hybla congestion control starves and the cwnd is kept constant
forever.

This patch forces an increment by one segment after #send_cwnd calls
without increments(newreno behavior).

Signed-off-by: Daniele Lacamera <root@danielinux.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-07 15:58:17 -07:00
Herbert Xu
58ec3b4db9 net: Fix netdev_run_todo dead-lock
Benjamin Thery tracked down a bug that explains many instances
of the error

unregister_netdevice: waiting for %s to become free. Usage count = %d

It turns out that netdev_run_todo can dead-lock with itself if
a second instance of it is run in a thread that will then free
a reference to the device waited on by the first instance.

The problem is really quite silly.  We were trying to create
parallelism where none was required.  As netdev_run_todo always
follows a RTNL section, and that todo tasks can only be added
with the RTNL held, by definition you should only need to wait
for the very ones that you've added and be done with it.

There is no need for a second mutex or spinlock.

This is exactly what the following patch does.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-07 15:50:03 -07:00
David S. Miller
742201e7ba Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/holtmann/bluetooth-2.6 2008-10-07 15:32:20 -07:00
Ali Saidi
53240c2087 tcp: Fix possible double-ack w/ user dma
From: Ali Saidi <saidi@engin.umich.edu>

When TCP receive copy offload is enabled it's possible that
tcp_rcv_established() will cause two acks to be sent for a single
packet. In the case that a tcp_dma_early_copy() is successful,
copied_early is set to true which causes tcp_cleanup_rbuf() to be
called early which can send an ack. Further along in
tcp_rcv_established(), __tcp_ack_snd_check() is called and will
schedule a delayed ACK. If no packets are processed before the delayed
ack timer expires the packet will be acked twice.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-07 15:31:19 -07:00