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162116 commits

Author SHA1 Message Date
Chandra Seetharaman
6c10db72c9 [SCSI] scsi_dh: Reference count scsi_dh_attach
Problem reported: http://marc.info/?l=dm-devel&m=124585978305866&w=2

scsi_dh does not do a refernce count for attach/detach, and this affects
the way it is supposed to work with multipath when a device is not
in the dev_list of the hardware handler.

This patch adds a reference count that counts each attach.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:51:51 -05:00
Douglas Gilbert
b4567ca630 [SCSI] update scsi/constants.c
It has been 3 years since this file was sync-ed with
www.t10.org . Information taken from the last bunch
of drafts released in May 2009. More asc/ascq codes
are coming for thin provisioning; when approved and
allocated another patch could add them prior to this
patch going live.

Changelog:
   - add some new command names and rename two commands
   - sync asc/ascq table with www.t10.org/lists/asc-num.txt
   - correct bug in scsi_extd_sense_format() [second
     for loop]

Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:51:50 -05:00
Luiz Augusto von Dentz
9e726b1742 Bluetooth: Fix rejected connection not disconnecting ACL link
When using DEFER_SETUP on a RFCOMM socket, a SABM frame triggers
authorization which when rejected send a DM response. This is fine
according to the RFCOMM spec:

    the responding implementation may replace the "proper" response
    on the Multiplexer Control channel with a DM frame, sent on the
    referenced DLCI to indicate that the DLCI is not open, and that
    the responder would not grant a request to open it later either.

But some stacks doesn't seems to cope with this leaving DLCI 0 open after
receiving DM frame.

To fix it properly a timer was introduced to rfcomm_session which is used
to set a timeout when the last active DLC of a session is unlinked, this
will give the remote stack some time to reply with a proper DISC frame on
DLCI 0 avoiding both sides sending DISC to each other on stacks that
follow the specification and taking care of those who don't by taking
down DLCI 0.

Signed-off-by: Luiz Augusto von Dentz <luiz.dentz@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 15:05:58 -07:00
Magnus Damm
9d7302299e PM: Run-time PM platform device bus support
This patch adds default Runtime PM callbacks to the dev_pm_ops
belonging to the platform bus. The callbacks are weak symbols
that architecture specific code can override.

Allows Runtime PM even though CONFIG_PM_SLEEP=n.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-08-23 00:05:31 +02:00
Rafael J. Wysocki
5e928f77a0 PM: Introduce core framework for run-time PM of I/O devices (rev. 17)
Introduce a core framework for run-time power management of I/O
devices.  Add device run-time PM fields to 'struct dev_pm_info'
and device run-time PM callbacks to 'struct dev_pm_ops'.  Introduce
a run-time PM workqueue and define some device run-time PM helper
functions at the core level.  Document all these things.

Special thanks to Alan Stern for his help with the design and
multiple detailed reviews of the pereceding versions of this patch
and to Magnus Damm for testing feedback.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@igel.co.jp>
2009-08-23 00:04:44 +02:00
Gustavo F. Padovan
ef54fd937f Bluetooth: Full support for receiving L2CAP SREJ frames
Support for receiving of SREJ frames as specified by the state table.

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 15:03:43 -07:00
Rafael J. Wysocki
8400146d0d Merge branch 'master' into for-linus 2009-08-23 00:03:00 +02:00
Gustavo F. Padovan
8f17154f1f Bluetooth: Add support for L2CAP SREJ exception
When L2CAP loses an I-frame we send a SREJ frame to the transmitter side
requesting the lost packet. This patch implement all Recv I-frame events
on SREJ_SENT state table except the ones that deal with SendRej (the REJ
exception at receiver side is yet not implemented).

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 15:01:25 -07:00
Gustavo F. Padovan
fcc203c30d Bluetooth: Add support for FCS option to L2CAP
Implement CRC16 check for L2CAP packets. FCS is used by Streaming Mode and
Enhanced Retransmission Mode and is a extra check for the packet content.

Using CRC16 is the default, L2CAP won't use FCS only when both side send
a "No FCS" request.

Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:59:49 -07:00
Gustavo F. Padovan
6840ed0770 Bluetooth: Enable Streaming Mode for L2CAP
Streaming Mode is helpful for the Bluetooth streaming based profiles, such
as A2DP. It doesn't have any error control or flow control.

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:57:58 -07:00
Gustavo F. Padovan
e90bac061b Bluetooth: Add support for Retransmission and Monitor Timers
L2CAP uses retransmission and monitor timers to inquiry the other side
about unacked I-frames. After sending each I-frame we (re)start the
retransmission timer. If it expires, we start a monitor timer that send a
S-frame with P bit set and wait for S-frame with F bit set. If monitor
timer expires, try again, at a maximum of L2CAP_DEFAULT_MAX_TX.

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:56:15 -07:00
Gustavo F. Padovan
30afb5b2aa Bluetooth: Initial support for retransmission of packets with REJ frames
When receiving an I-frame with unexpected txSeq, receiver side start the
recovery procedure by sending a REJ S-frame to the transmitter side. So
the transmitter can re-send the lost I-frame.

This patch just adds a basic support for retransmission, it doesn't
mean that ERTM now has full support for packet retransmission.

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:55:20 -07:00
Gustavo F. Padovan
c74e560cd0 Bluetooth: Add support for Segmentation and Reassembly of SDUs
ERTM should use Segmentation and Reassembly to break down a SDU in many
PDUs on sending data to the other side.

On sending packets we queue all 'segments' until end of segmentation and
just the add them to the queue for sending. On receiving we create a new
SKB with the SDU reassembled.

Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:53:58 -07:00
Gustavo F. Padovan
1c2acffb76 Bluetooth: Add initial support for ERTM packets transfers
This patch adds support for ERTM transfers, without retransmission, with
txWindow up to 63 and with acknowledgement of packets received. Now the
packets are queued before call l2cap_do_send(), so packets couldn't be
sent at the time we call l2cap_sock_sendmsg(). They will be sent in
an asynchronous way on later calls of l2cap_ertm_send(). Besides if an
error occurs on calling l2cap_do_send() we disconnect the channel.

Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:53:01 -07:00
Gustavo F. Padovan
22121fc915 Bluetooth: Create separate l2cap_send_disconn_req() function
The code for sending a disconnect request was repeated several times
within L2CAP source code. So move this into its own function.

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:50:07 -07:00
Gustavo F. Padovan
f2fcfcd670 Bluetooth: Add configuration support for ERTM and Streaming mode
Add support to config_req and config_rsp to configure ERTM and Streaming
mode. If the remote device specifies ERTM or Streaming mode, then the
same mode is proposed. Otherwise ERTM or Basic mode is used. And in case
of a state 2 device, the remote device should propose the same mode. If
not, then the channel gets disconnected.

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:50:07 -07:00
Marcel Holtmann
65c7c49184 Bluetooth: Add L2CAP RFC option if ERTM is enabled
When trying to establish a connection with Enhanced Retransmission mode
enabled, the RFC option needs to be added to the configuration.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:50:07 -07:00
Marcel Holtmann
c6b03cf986 Bluetooth: Allow setting of L2CAP ERTM via socket option
To enable Enhanced Retransmission mode it needs to be set via a socket
option. A different mode can be set on a socket, but on listen() and
connect() the mode is checked and ERTM is only allowed if it is enabled
via the module parameter.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:50:07 -07:00
Marcel Holtmann
44dd46de32 Bluetooth: Add module option to enable L2CAP ERTM support
Since the Enhanced Retransmission mode for L2CAP is still under heavy
development disable it by default and provide a module option to enable
it manually for testing.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:50:07 -07:00
Marcel Holtmann
52d18347df Bluetooth: Coding style cleanup from previous rfcomm_init bug fix
The rfcomm_init bug fix went into the kernel premature before it got fully
reviewed and acknowledged by the Bluetooth maintainer. So fix up the coding
style now.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:49:36 -07:00
Thomas Gleixner
a6a67efd70 Bluetooth: Convert hdev->req_lock to a mutex
hdev->req_lock is used as mutex so make it a mutex.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:35:02 -07:00
Julia Lawall
5959809ded Bluetooth: Add missing kmalloc NULL tests to Marvell driver
Check that the result of kmalloc is not NULL before dereferencing it.
The patch also replaces kmalloc + memset by kzalloc.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression *x;
identifier f;
constant char *C;
@@

x = \(kmalloc\|kcalloc\|kzalloc\)(...);
... when != x == NULL
    when != x != NULL
    when != (x || ...)
(
kfree(x)
|
f(...,C,...,x,...)
|
*f(...,x,...)
|
*x->f
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:33:22 -07:00
Bing Zhao
3318b2362b Bluetooth: Fix incorrect alignment in Marvell BT-over-SDIO driver
The driver uses "u32" for alignment check and calculation which
works only on 32-bit system. It will crash the 64-bit system.
Replace "u32" with "unsigned long" to fix this issue.

Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:34 -07:00
Marcel Holtmann
9374253ffe Bluetooth: Remove Enter/Leave debug statements from Marvell driver
The Marvell Bluetooth driver is full of Enter/Leave debug statements and
all of them are really pointless and only clutter the code. Seems to be
some left-overs when they ported the driver from Windows. For the Linux
driver lets remove these.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:34 -07:00
Marcel Holtmann
e0721f99ba Bluetooth: Fix last few compiler warning within Marvell core driver
After fixing the driver to use skb_put properly for their HCI commands
only a few compiler warnings are left. Add proper casting for them.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:34 -07:00
Marcel Holtmann
91d697302b Bluetooth: Fix Marvell driver to use skb_put and hci_opcode_pack
The Marvell driver has some weird quirks on how to construct proper SKBs
with Bluetooth HCI commands. Fix it to use skb_put properly and also
use hci_opcode_pack instead of self-crafted macro.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:34 -07:00
Marcel Holtmann
60dee5ccd7 Bluetooth: Remove private device name of Marvell SDIO driver
For some reason the btmrvl_device struct has a name field that the SDIO
fills in, but then never ever uses again. That is totally pointless and
so just remove it.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:34 -07:00
Marcel Holtmann
9666fb356d Bluetooth: Fix module description strings for Marvell driver
Make the module description entries for the core and also the Marvell
SDIO driver match common practive inside the Bluetooth subsystem.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:34 -07:00
Marcel Holtmann
dcf47f3bc7 Bluetooth: Fix complicated assignment of firmware for Marvell devices
The Marvell Bluetooth SDIO driver has a really complicated concept on how
firmware names are assigned to specific device ids. Fix that by doing a
proper structure and assign it to the module device table.

And while at it fix various coding style weirdness that is still present
in this driver.

Signed-off-by: Marcel Holtman <marcel@holtmann.org>
2009-08-22 14:25:33 -07:00
Marcel Holtmann
4271e08d8b Bluetooth: Some coding style cleanup for Marvell core driver
The Marvell core Bluetooth driver has various weird casting and unneeded
braces in its code that makes it hard to read. Remove all of these to
make the code a little bit simpler.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:33 -07:00
Marcel Holtmann
542399037d Bluetooth: Remove pointless casts from Marvell debugfs support
The Marvell Bluetooth driver has debugfs support and they are casting
like there is no tomorrow. Remove all of them and magically the code
becomes more readable.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:33 -07:00
Marcel Holtmann
944fe798c6 Bluetooth: Remove pointless ifdef protection for Marvell header files
Both header files of the Marvell Bluetooth driver are private anyway and
if the driver happens to include them twice or they create a circular
dependency then the driver needs fixing. So just remove both pointless
ifdefs.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:33 -07:00
Marcel Holtmann
08b0b0ce8c Bluetooth: Fix compilation of Marvell driver without debugfs
The Makefile entry for the Marvell driver is broken when it comes to
handling the optional DEBUG_FS correctly. That must have been the reason
why they were using select in Kconfig in the first place. Fix this and
make it really optional.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:33 -07:00
Marcel Holtmann
e7a25f9839 Bluetooth: Fix Kconfig for Marvell Bluetooth driver
The Marvell driver selects DEBUG_FS and FW_LOADER for its core driver
and that is pointless. Don't select DEBUG_FS since it is either enabled
or not and it is not for the driver to enable it. Also FW_LOADER is
only used within the SDIO driver and so just have that one select the
FW_LOADER option.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:33 -07:00
Bing Zhao
196be0cd01 Bluetooth: Add documentation for Marvell Bluetooth driver
add btmrvl.txt to Documentation/

This patch incorporates a lot of comments given by
Nicolas Pitre <nico@marvell.com>. Many thanks to Nicolas Pitre.

Signed-off-by: Rahul Tank <rahult@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:32 -07:00
Bing Zhao
fb784f0508 Bluetooth: Add debugfs support to btmrvl driver
/debug/btmrvl/config/
/debug/btmrvl/status/

See Documentation/btmrvl.txt for details.

This patch incorporates a lot of comments given by
Nicolas Pitre <nico@marvell.com>. Many thanks to Nicolas Pitre.

Signed-off-by: Rahul Tank <rahult@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:32 -07:00
Bing Zhao
789221ecc8 Bluetooth: Add Marvell BT-over-SDIO driver
This driver supports Marvell Bluetooth enabled devices with SDIO
interface. Currently only SD8688 chip is supported.

The helper/firmware images of SD8688 can be downloaded from this tree:
git://git.infradead.org/users/dwmw2/linux-firmware.git

This patch incorporates a lot of comments given by
Nicolas Pitre <nico@marvell.com>. Many thanks to Nicolas Pitre.

Signed-off-by: Rahul Tank <rahult@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:32 -07:00
Bing Zhao
132ff4e5fa Bluetooth: Add btmrvl driver for Marvell Bluetooth devices
This driver provides basic definitions and library functions to
support Marvell Bluetooth enabled devices, such as 88W8688 WLAN/BT
combo chip.

This patch incorporates a lot of comments given by
Nicolas Pitre <nico@marvell.com>. Many thanks to Nicolas Pitre.

Signed-off-by: Rahul Tank <rahult@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:25:32 -07:00
Marcel Holtmann
edad638869 Bluetooth: Let HIDP grab the device reference for connections
The core exports the hci_conn_hold_device() and hci_conn_put_device()
functions for device reference of connections. Use this to ensure that
the uevents from the parent are send after the child ones.

Based on a report by Brian Rogers <brian@xyzw.org>

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:22:15 -07:00
Marcel Holtmann
9eba32b86d Bluetooth: Add extra device reference counting for connections
The device model itself has no real usable reference counting at the
moment and this causes problems if parents are deleted before their
children. The device model itself handles the memory details of this
correctly, but the uevent order is not consistent. This causes various
problems for systems like HAL or even X.

So until device_put() does a proper cleanup, the device for Bluetooth
connection will be protected with an extra reference counting to ensure
the correct order of uevents when connections are terminated.

This is not an automatic feature. Higher Bluetooth layers like HIDP or
BNEP should grab this new reference to ensure that their uevents are
send before the ones from the parent device.

Based on a report by Brian Rogers <brian@xyzw.org>

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:19:26 -07:00
Marcel Holtmann
364f63519d Bluetooth: Disconnect HIDRAW devices on disconnect
Currently the HID subsystem will create HIDRAW devices for the transport
driver, but it will not disconnect them. Until the HID subsytem gets
fixed, ensure that HIDRAW and HIDDEV devices are disconnected when the
Bluetooth HID device gets removed.

Based on a patch from Brian Rogers <brian@xyzw.org>

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:15:53 -07:00
Vikram Kandukuri
290ba20081 Bluetooth: Improve USB driver throughput by increasing the frame size
This patch increases the receive buffer size to HCI_MAX_FRAME_SIZE
which improves the RX throughput considerably.

Tested against BRM/Atheros/CSR USB Dongles with PAN profile using
iperf and chariot. This gave significant (around 40%) increase
in performance (increased from 0.8 to 1.5 Mb/s in Sheld room)

Signed-off-by: Vikram Kandukuri <vikram.kandukuri@atheros.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:12:37 -07:00
Vikram Kandukuri
981b1414d7 Bluetooth: Fix missing scheduling when VIRTUAL_CABLE_UNPLUG is received
There is a test case in PTS tool; PTS will send the VIRTUAL_CABLE_UNPLUG
command to IUT. Then IUT should disconnect the channel and kill the HID
session when it receives the command. The VIRTUAL_CABLE_UNPLUG command
is parsed by HID transport, but it is not scheduled to do so. Add a
call to hidp_schedule() to kill the session.

Signed-off-by: Jothikumar Mothilal <jothikumar.mothilal@atheros.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-08-22 14:12:17 -07:00
Marcel Holtmann
fd0b3ff707 Bluetooth: Add proper shutdown support to SCO sockets
The SCO sockets for Bluetooth audio setup and streaming are missing the
shutdown implementation. This hasn't been a problem so far, but with a
more deeper integration with PulseAudio it is important to shutdown SCO
sockets properly.

Also the Headset profile 1.2 has more detailed qualification tests that
require that SCO and RFCOMM channels are terminated in the right order. A
proper shutdown function is necessary for this.

Based on a report by Johan Hedberg <johan.hedberg@nokia.com>

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Johan Hedberg <johan.hedberg@nokia.com>
2009-08-22 14:11:46 -07:00
Linus Torvalds
3edf2fb9d8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: check saved state before restore
2009-08-22 12:14:01 -07:00
Linus Torvalds
e3054ea7f7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] mpt2sas: fix config request and diag reset deadlock
  [SCSI] mpt2sas: Bump driver version 01.100.04.00
  [SCSI] mpt2sas: fix oops because drv data points to NULL on resume from hibernate
  [SCSI] mpt2sas: fix crash due to Watchdog is active while OS in standby mode
  [SCSI] mpt2sas: fix infinite loop inside config request
  [SCSI] mpt2sas: Excessive log info causes sas iounit page time out
  [SCSI] mpt2sas: Raid 10 Value is showing as Raid 1E in /va/log/messages
  [SCSI] mpt2sas: Expander fix oops saying "Already part of another port"
  [SCSI] mpt2sas: Introduced check for enclosure_handle to avoid crash
2009-08-22 08:30:58 -07:00
Paul E. McKenney
b560d8ad85 rcu: Expunge lingering references to CONFIG_CLASSIC_RCU, optimize on !SMP
A couple of references to CONFIG_CLASSIC_RCU have survived.
Although these are harmless, it is past time for them to go.
The one in hardirq.h is strictly a readability problem.

The two in pagemap.h appear to disable a !SMP performance
optimization (which this patch re-enables).

This does raise the issue as to whether pagemap.h should really
be referring to the CPU implementation.  Long term, I intend to
make the RCU implementation driven by CONFIG_PREEMPT, at which
point these should change from defined(CONFIG_TREE_RCU) to
!defined(CONFIG_PREEMPT). In the meantime, is there something
else that could be done in pagemap.h?

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <20090822050851.GA8414@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-22 13:07:09 +02:00
Linus Torvalds
422bef879e Linux 2.6.31-rc7 2009-08-21 18:00:46 -07:00
Linus Torvalds
8e9d78edea Re-introduce page mapping check in mark_buffer_dirty()
In commit a8e7d49aa7 ("Fix race in
create_empty_buffers() vs __set_page_dirty_buffers()"), I removed a test
for a NULL page mapping unintentionally when some of the code inside
__set_page_dirty() was moved to the callers.

That removal generally didn't matter, since a filesystem would serialize
truncation (which clears the page mapping) against writing (which marks
the buffer dirty), so locking at a higher level (either per-page or an
inode at a time) should mean that the buffer page would be stable.  And
indeed, nothing bad seemed to happen.

Except it turns out that apparently reiserfs does something odd when
under load and writing out the journal, and we have a number of bugzilla
entries that look similar:

	http://bugzilla.kernel.org/show_bug.cgi?id=13556
	http://bugzilla.kernel.org/show_bug.cgi?id=13756
	http://bugzilla.kernel.org/show_bug.cgi?id=13876

and it looks like reiserfs depended on that check (the common theme
seems to be "data=journal", and a journal writeback during a truncate).

I suspect reiserfs should have some additional locking, but in the
meantime this should get us back to the pre-2.6.29 behavior.

Pattern-pointed-out-by: Roland Kletzing <devzero@web.de>
Cc: stable@kernel.org (2.6.29 and 2.6.30)
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-21 17:40:08 -07:00
H. Peter Anvin
5400743db5 x86, mtrr: make mtrr_aps_delayed_init static bool
mtr_aps_delayed_init was declared u32 and made global, but it only
ever takes boolean values and is only ever used in
arch/x86/kernel/cpu/mtrr/main.c.  Declare it "static bool" and remove
external references.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
2009-08-21 17:00:02 -07:00