Commit Graph

163745 Commits

Author SHA1 Message Date
Robin Getz
3f871feaf3 Blackfin: add an early shadow console
Add a memory based shadow console to keep a copy of the printk buffer in a
location which can be found externally.  This allows bootloaders to locate
and utilize the log buffer in case of silent (early/resume/etc...) crashes.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:31:43 -04:00
Mike Frysinger
53e18df745 Blackfin: add support for common FDPIC ptrace requests
The FDPIC arches support a standard set of ptrace requests so rather than
define our own custom API, hook up those requests for common code to
leverage.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:31:42 -04:00
Mike Frysinger
81c969a8bc Blackfin: push SRAM locks down into related ifdefs
Rather than defining the locks and initializing them all the time, only do
so when we actually need them (i.e. the SRAM regions exist).  This avoids
dead data and code bloat during runtime.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:31:41 -04:00
Sonic Zhang
9c954f8941 Blackfin: unify duplicated SMP checks in L2 cache kconfig
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:59 -04:00
Michael Hennerich
204844ebd0 Blackfin: rename PCF8574 driver config
The "TWI_KEYPAD" driver was renamed to "INPUT_PCF8574", so update the
defines in the board resources accordingly.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:57 -04:00
Robin Getz
2f812c0bd5 Blackfin: clean up early memory setup code
Remove code duplication, and only print out memory warnings when they are
an actual problem.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:54 -04:00
Mike Frysinger
a769094061 Blackfin: fix module reloc handling for all memory regions
The current module relocation code has spotty handling wrt different
memory regions (like L1 instruction).  Rather than try to fix each
little spot, use the new common memory functions to greatly simplify
everything and make sure it is always correct.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:52 -04:00
Mike Frysinger
459fec9073 Blackfin: cleanup module section checking
The current module section handling code has a lot of verbose statements
copied and pasted throughout which makes it pretty hard to digest at a
glance.  By unifying all of these up front, it is a lot easier to quickly
get an idea of what is actually going on.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:51 -04:00
Mike Frysinger
70deca9f9c Blackfin: convert malloc()/memset() to zalloc() in module code
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:49 -04:00
Mike Frysinger
dc6b1ac984 Blackfin: cleanup printk() usage in module code
Convert all printk() statements to use the common pr_xxx() funcs and use
the new pr_fmt() function to standardize all of the output.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:48 -04:00
Robin Getz
22532578ee Blackfin: reject outdated/unused/wrong relocation types
All kernel modules are required to be built with -mlong-calls and thus
should not generate any of these relocations.  If they do, it means the
module has not been compiled properly, so rather than trying to handle
them (and running into random run time errors) just error out on module
load to force the module to be compiled correctly.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:46 -04:00
Mike Frysinger
c014e15a2f Blackfin: convert ptrace to new memory functions
Now that we have a Blackfin memory function to figure out how to properly
access the different regions, drop the custom memory range checks in our
ptrace code and use that.  It makes the code nicer and fixes bugs where
the ptrace logic wasn't handling all the different regions.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:45 -04:00
Mike Frysinger
18070dd669 Blackfin: cleanup traps decode_address() a bit
Unify the address display to shrink the code, and add missing decoding of
a few special Blackfin-specific regions (L1 ROM and MMRs).

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:43 -04:00
Philippe Gerum
f4e129399c Blackfin: inline I-pipe bypass code in ret_from_exception
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:42 -04:00
Philippe Gerum
9ea7770fdb Blackfin: sanitize manual control of IPEND[4]
Cleanup is performed in two ways:

- remove extraneous updates of IPEND[4] w/ CONFIG_IPIPE,
  and document remaining use.

- substitute pop-reg-from-stack instructions with plain SP fixups in
  all save-RETI-then-discard patterns.

Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:40 -04:00
Philippe Gerum
7a7967dc1b Blackfin: document __ipipe_call_irqtail
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:38 -04:00
Philippe Gerum
70f4720232 Blackfin: allow EVT5 to preempt irqtail prologue (CONFIG_DEBUG_HWERR)
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:37 -04:00
Philippe Gerum
fc9afb997f Blackfin: reuse evt_evt14 handler to perform irqtail epilogue
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:36 -04:00
Philippe Gerum
9703a73c98 Blackfin: use generic name for EVT14 handler
The purpose of the EVT14 handler may depend on whether CONFIG_IPIPE is
enabled, albeit its implementation can be the same in both cases. When
the interrupt pipeline is enabled, EVT14 can be used to raise the core
priority level for the running code; when CONFIG_IPIPE is off, EVT14
can be used to lower this level before running softirq handlers.

Rename evt14_softirq to evt_evt14 to pick an identifier that fits
both, which allows to reuse the same vector setup code as well.

Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:34 -04:00
Philippe Gerum
6b8019c85e Blackfin: allow high priority domains to preempt schedule_tail()
ret_from_fork is always entered with hw interrupts off, which prevents
real-time domains to preempt the Linux kernel during part of the
initial context switch to the new task, which could in turn raise the
worst-case latency figures.

To avoid this, stall the root domain stage in the interrupt pipeline
to keep the scheduling tail code free from Linux-handled IRQs, then
enable hardware interrupts again.

Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:33 -04:00
Philippe Gerum
bc569f1a77 Blackfin: export show_stack() to modules
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:32 -04:00
Philippe Gerum
b9c7eb498d Blackfin: fix misnomer of some I-pipe helpers
__ipipe_{stall, unstall}_root_raw() identifiers may leave the reader
under the impression that only the virtual state is affected by these
operations, which is wrong. Pick names following the convention used
throughout the interrupt pipeline code.

Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:30 -04:00
Philippe Gerum
d8ca63955a Blackfin: checkpatch --file arch/blackfin/kernel/ipipe.c
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:29 -04:00
Robin Getz
ae4f073c40 Blackfin: make EVT3->EVT5 lowering more robust wrt IPEND[4]
We handle many exceptions at EVT5 (hardware error level) so that we can
catch exceptions in our exception handling code.  Today - if the global
interrupt enable bit (IPEND[4]) is set (interrupts disabled) our trap
handling code goes into a infinite loop, since we need interrupts to be
on to defer things to EVT5.

Normal kernel code should not trigger this for any reason as IPEND[4] gets
cleared early (when doing an interrupt context save) and the kernel stack
there should be sane (or something much worse is happening in the system).
But there have been a few times where this has happened, so this change
makes sure we dump a proper crash message even when things have gone south.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:28 -04:00
Barry Song
d4b834c139 Blackfin: bf537-stamp: add resources for AD1938 audio card
Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:26 -04:00
Yi Li
e68d1ebc30 Blackfin: bf537-stamp: declare SPI IRQ resources
Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:24 -04:00
Michael Hennerich
f39d56ec46 Blackfin: bf537-stamp: update ADP5588 header name
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:23 -04:00
Jens Rosenboom
3933fc952a ipv6: Ignore route option with ROUTER_PREF_INVALID
RFC4191 says that "If the Reserved (10) value is received, the Route
Information Option MUST be ignored.", so this patch makes us conform
to the RFC. This is different to the usage of the Default Router
Preference, where an invalid value must indeed be treated as
PREF_MEDIUM.

Signed-off-by: Jens Rosenboom <me@jayr.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-16 17:10:38 -07:00
Jiri Pirko
b9f602533e bonding: make ab_arp select active slaves as other modes
When I was implementing primary_passive option (formely named primary_lazy) I've
run into troubles with ab_arp. This is the only mode which is not using
bond_select_active_slave() function to select active slave and instead it
selects it itself. This seems to be not the right behaviour and it would be
better to do it in bond_select_active_slave() for all cases. This patch makes
this happen. Please review.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-16 17:04:58 -07:00
David S. Miller
c127bdf9f6 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 2009-09-16 17:01:24 -07:00
Theodore Ts'o
fb40ba0d98 ext4: Add a tracepoint for ext4_alloc_da_blocks()
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 19:30:40 -04:00
Theodore Ts'o
1b9c12f44c ext4: store EXT4_EXT_MIGRATE in i_state instead of i_flags
EXT4_EXT_MIGRATE is only intended to be used for an in-memory flag,
and the hex value assigned to it collides with FS_DIRECTIO_FL (which
is also stored in i_flags).  There's no reason for the
EXT4_EXT_MIGRATE bit to be stored in i_flags, so we switch it to use
i_state instead.

Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-17 08:32:22 -04:00
Johannes Berg
bbac31f4c0 cfg80211: fix SME connect
There's a check saying
	/* we're good if we have both BSSID and channel */
	if (wdev->conn->params.bssid && wdev->conn->params.channel) {

but that isn't true -- we need the BSS struct. This leads
to errors such as

    Trying to associate with 00:1b:53:11:dc:40 (SSID='TEST' freq=2412 MHz)
    ioctl[SIOCSIWFREQ]: No such file or directory
    ioctl[SIOCSIWESSID]: No such file or directory
    Association request to the driver failed
    Associated with 00:1b:53:11:dc:40

in wpa_supplicant, as reported by Holger.

Instead, we really need to have the BSS struct, and if we
don't, then we need to initiate a scan for it. But we may
already have the BSS struct here, so hang on to it if we
do and scan if we don't.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Tested-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-09-16 16:21:00 -04:00
Pavel Roskin
8c6c03fe23 rc80211_minstrel: fix contention window calculation
The contention window is supposed to be a power of two minus one, i.e.
15, 31, 63, 127...  minstrel_rate_init() forgets to subtract 1, so the
sequence becomes 15, 32, 66, 134...

Bug reported by Dan Halperin <dhalperi@cs.washington.edu>

Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-09-16 16:21:00 -04:00
Randy Dunlap
de32cce132 ssb/sdio: fix printk format warnings
Fix printk format warnings:

drivers/ssb/sdio.c:336: warning: format '%u' expects type 'unsigned int', but argument 7 has type 'size_t'
drivers/ssb/sdio.c:443: warning: format '%u' expects type 'unsigned int', but argument 7 has type 'size_t'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-09-16 16:21:00 -04:00
Christian Lamparter
f7f71173ea p54usb: add Zcomax XG-705A usbid
This patch adds a new usbid for Zcomax XG-705A to the device table.

Cc: stable@kernel.org
Reported-by: Jari Jaakola <jari.jaakola@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-09-16 16:20:59 -04:00
Huang Weiyi
d4e54e871f ASoC: remove unused #include <linux/version.h>
Remove unused #include <linux/version.h>('s) in
  sound/soc/codecs/ad1836.c
  sound/soc/codecs/ad1938.c
  sound/soc/codecs/wm8974.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2009-09-16 21:08:54 +01:00
Anirban Sinha
f4c3f03838 Fix ia64 build breakage in head.S
The "cleanup console_print()" patch in commit
353f6dd2de introduced an "extern"
declaration into an assembly language file.  Remove it.

Signed-off-by: Anirban Sinha <asinha@zeugmasystems.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-16 12:28:52 -07:00
Ingo Molnar
40d9d82c8a Merge branch 'tip/tracing/core4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/core 2009-09-16 21:16:37 +02:00
Eric Sandeen
fb0a387dcd ext4: limit block allocations for indirect-block files to < 2^32
Today, the ext4 allocator will happily allocate blocks past
2^32 for indirect-block files, which results in the block
numbers getting truncated, and corruption ensues.

This patch limits such allocations to < 2^32, and adds
BUG_ONs if we do get blocks larger than that.

This should address RH Bug 519471, ext4 bitmap allocator 
must limit blocks to < 2^32

* ext4_find_goal() is modified to choose a goal < UINT_MAX,
  so that our starting point is in an acceptable range.

* ext4_xattr_block_set() is modified such that the goal block
  is < UINT_MAX, as above.

* ext4_mb_regular_allocator() is modified so that the group
  search does not continue into groups which are too high

* ext4_mb_use_preallocated() has a check that we don't use
  preallocated space which is too far out

* ext4_alloc_blocks() and ext4_xattr_block_set() add some BUG_ONs

No attempt has been made to limit inode locations to < 2^32,
so we may wind up with blocks far from their inodes.  Doing
this much already will lead to some odd ENOSPC issues when the
"lower 32" gets full, and further restricting inodes could
make that even weirder.

For high inodes, choosing a goal of the original, % UINT_MAX,
may be a bit odd, but then we're in an odd situation anyway,
and I don't know of a better heuristic.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 14:45:10 -04:00
Akira Fujita
c40ce3c9ea ext4: Fix different block exchange issue in EXT4_IOC_MOVE_EXT
If logical block offset of original file which is passed to
EXT4_IOC_MOVE_EXT is different from donor file's,
a calculation error occurs in ext4_calc_swap_extents(),
therefore wrong block is exchanged between original file and donor file.
As a result, we hit ext4_error() in check_block_validity().
To detect the logical offset difference in EXT4_IOC_MOVE_EXT,
add checks to mext_calc_swap_extents() and handle it as error,
since data exchange must be done between the same blocks in EXT4_IOC_MOVE_EXT.

Reported-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 14:25:39 -04:00
Akira Fujita
347fa6f1c7 ext4: Add null extent check to ext_get_path
There is the possibility that path structure which is taken
by ext4_ext_find_extent() indicates null extents.
Because during data block exchanging in ext4_move_extents(),
constitution of an extent tree may be changed.
As a solution, the patch adds null extent check
to ext_get_path().

Reported-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 14:25:07 -04:00
Akira Fujita
2147b1a6a4 ext4: Replace BUG_ON() with ext4_error() in move_extents.c
Replace BUG_ON calls with a call to ext4_error()
to print an error message if EXT4_IOC_MOVE_EXT failed
with some kind of reasons.  This will help to debug.
Ted pointed this out, thanks.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 13:46:35 -04:00
Akira Fujita
e8505970af ext4: Replace get_ext_path macro with an inline funciton
Replace get_ext_path macro with an inline function,
since this macro looks like a function call but its arguments
get modified. Ted pointed this out, thanks.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 13:46:38 -04:00
Muralidharan Karicheri
85609c1ccd DaVinci: DM646x - platform changes for vpif capture and display drivers
VPIF display changes (Chaithrika)

Add platform device and resource structures. Also define a platform specific
clock setup function that can be accessed by the driver to configure the clock
and CPLD.

VPIF caputure changes (Murali)

1) Modify vpif_subdev_info to add board_info, routing information and
   vpif interface configuration. Remove addr since it is part of
   board_info

2) Add code to setup channel mode and input decoder path for vpif
   capture driver

Also incorporated comments against version v0 of the patch series and
added a spinlock to protect writes to common registers

Tested on DM6467 on channel 0 using TVP514x. Following bootargs used
for drivers:

   vpif_capture.ch0_bufsize=829440 vpif_display.ch2_bufsize=829440

Signed-off-by: Manjunath Hadli <mrh@ti.com>
Signed-off-by: Brijesh Jadav <brijesh.j@ti.com>
Signed-off-by: Chaithrika U S <chaithrika@ti.com>
Reviewed-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Muralidharan Karicheri <m-karicheri2@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-09-16 10:28:46 -07:00
Muralidharan Karicheri
51e68e27d3 davinci: DM355 - platform changes for vpfe capture
DM355 platform and board setup

This has platform and board setup changes to support vpfe capture
driver for DM355 EVMs.

Tested video capture on DM355 using tvp514x

Reviewed-by: Hans Verkuil <hverkuil@xs4all.nl>
Reviewed-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Reviewed-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Muralidharan Karicheri <m-karicheri2@ti.com>
Signed-off-by: Denys Dmytriyenko <denis@denix.org>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-09-16 10:25:45 -07:00
Muralidharan Karicheri
ab8e8df874 davinci: DM644x platform changes for vpfe capture
DM644x platform and board setup

This adds platform and board setup changes required to support
vpfe capture driver on DM644x

Tested video capture on DM6446 with tvp514x driver

Reviewed-by: Hans Verkuil <hverkuil@xs4all.nl>
Reviewed-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Reviewed-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Muralidharan Karicheri <m-karicheri2@ti.com>
Signed-off-by: Denys Dmytriyenko <denis@denix.org>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-09-16 10:25:26 -07:00
Jan Kara
56fcad29d4 ext3: Flush disk caches on fsync when needed
In case we fsync() a file and inode is not dirty, we don't force a transaction
to disk and hence don't flush disk caches. Thus file data could be just in disk
caches and not on persistent storage. Fix the problem by flushing disk caches
if we didn't force a transaction commit.

Signed-off-by: Jan Kara <jack@suse.cz>
2009-09-16 17:44:11 +02:00
Chris Mason
4f003fd32b ext3: Add locking to ext3_do_update_inode
I've been struggling with this off and on while I've been testing the
data=guarded work.  The symptom is corrupted orphan lists and inodes
with the wrong i_size stored on disk.  I was convinced the
data=guarded code was just missing a call to ext3_mark_inode_dirty, but
tracing showed the i_disksize I was sending to ext3_mark_inode_dirty
wasn't actually making it to the drive.

ext3_mark_inode_dirty can be called without locks held (atime updates
and a few others), so the data=guarded code uses locks while updating
the in-memory inode, and then calls ext3_mark_inode_dirty
without any locks held.

But, ext3_mark_inode_dirty has no internal locking to make sure that
only one CPU is updating the buffer head at a time.  Generally this
works out ok because everyone that changes the inode then calls
ext3_mark_inode_dirty themselves.  Even though it races, eventually
someone updates the buffer heads and things move on.

But there is still a risk of the wrong values getting in, and the
data=guarded code seems to hit the race very often.

Since everyone that changes the inode also logs it, it should be
possible to fix this with some memory barriers.  I'll leave that as an
exercise to the reader and lock the buffer head instead.

It it probably a good idea to have a different patch series for lockless
bit flipping on the ext3 i_state field.  ext3_do_update_inode &= clears
EXT3_STATE_NEW without any locks held.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2009-09-16 17:44:11 +02:00
Jan Kara
00171d3c7e ext3: Fix possible deadlock between ext3_truncate() and ext3_get_blocks()
During truncate we are sometimes forced to start a new transaction as the
amount of blocks to be journaled is both quite large and hard to predict. So
far we restarted a transaction while holding truncate_mutex and that violates
lock ordering because truncate_mutex ranks below transaction start (and it
can lead to a real deadlock with ext3_get_blocks() allocating new blocks
from ext3_writepage()).

Luckily, the problem is easy to fix: We just drop the truncate_mutex before
restarting the transaction and acquire it afterwards. We are safe to do this as
by the time ext3_truncate() is called, all the page cache for the truncated
part of the file is dropped and so writepage() cannot come and allocate new
blocks in the part of the file we are truncating. The rest of writers is
stopped by us holding i_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
2009-09-16 17:44:11 +02:00