Commit graph

209366 commits

Author SHA1 Message Date
Uwe Kleine-König
3b16bb539c mfd: New mc13783 function exposing flags
This is needed for the mc13783-adc driver to decide if a touch screen is
connected.  If so some channels are not available as generic hwmon inputs.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:28:03 +02:00
Axel Lin
789133b7b4 mfd: Check jz4740-adc kmalloc() result
If kmalloc() fails exit with -ENOMEM.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:28:02 +02:00
Axel Lin
48736c80e5 mfd: Fix jz4740-adc resource reclaim in probe error path
If mfd_add_devices() fail, we need to relese allocated resources.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:28:01 +02:00
Mark Brown
889135210b mfd: Add WM8321 support
The WM8321 is a PMIC for low power, high performance applications. From a
software point of view the device is identical to the WM8320, all the
differences between the two devices are visible only in hardware.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:28:00 +02:00
Sundar R Iyer
5981f4e65c mfd: Add stmpe auto sleep feature
Some STMPE devices support entering sleep mode automatically on a
specified timeout of inactivity on the I2C bus with the host system.

Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Sundar R Iyer <sundar.iyer@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:28:00 +02:00
Kulikov Vasiliy
3faeb35ccc touchscreen: Fix sign bug
platform_get_irq_byname() can return negative results, it is not seen to
unsigned ts_irq. Make it signed.

Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Acked-By: Luotao Fu <l.fu@pengutronix.de>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:59 +02:00
Hemanth V
31fc03df5d mfd: Add support for TWL6030 PWM
TWL6030 supports PWM (Pulse Width Modulator) which is used
to control charging LED. PWM allows for controlling brightness.
This patch implements the APIs required by leds-pwm driver.

Signed-off-by: Hemanth V <hemanthv@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:59 +02:00
Mark Brown
9accdc1bf2 mfd: Add additional WM8994 GPIO functions
Later revisions of the WM8994 add some more GPIO functions, define them
in the header file.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:58 +02:00
Lars-Peter Clausen
91f4debf5e mfd: Add JZ4740 ADC driver
This patch adds a MFD driver for the JZ4740 ADC unit. The driver is used to
demultiplex IRQs and synchronize access to shared registers between the
battery, hwmon and (future) touchscreen driver.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:58 +02:00
Mark Brown
b12c35e22d gpiolib: Implement set_debounce for WM831x GPIOs
The debounce times are approximate, they can be selected using the two
input functions.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:57 +02:00
Luotao Fu
f94add3bd4 input: STMPE touch controller support
This one adds a driver for STMPE touchscreen controllers.
This driver depends on the stmpexxx mfd core driver.

Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:56 +02:00
Rabin Vincent
76f1084531 input: Add STMPE keypad driver
Add an input driver for the keypad on STMPE I/O expanders.  This driver
uses the common support provided by the STMPE MFD driver.

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:56 +02:00
Rabin Vincent
03f822f5e5 gpio: Add STMPE GPIO driver
Add support for the GPIOs on STMPE I/O Expanders.

[l.fu@pengutronix.de: fix set direction input]
[l.fu@pengutronix.de: set GPIO alternate function while requesting]
Acked-by: Luotao Fu <l.fu@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:55 +02:00
Rabin Vincent
27e34995e1 mfd: Add STMPE I/O Expander support
Add support for the STMPE family of I/O Expanders from
STMicroelectronics.  These devices include upto 24 gpios and a varying
selection of blocks, including PWM, keypad, and touchscreen controllers.
This patch adds the MFD core.

[l.fu@pengutronix.de: fix stmpe811 enable hook]
[l.fu@pengutronix.de: add touchscreen platform data]
Acked-by: Luotao Fu <l.fu@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:24 +02:00
Axel Lin
d2d272a965 mfd: Properly free t7l66xb clk32k clock source
This patch includes below fixes to properly free clk32k clock source:
1. remove a redundant clk_put in t7l66xb_probe error path
2. add missing clk_disable(t7l66xb->clk32k) and clk_put(t7l66xb->clk32k)
   to properly free the clock source.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:23 +02:00
Samuel Ortiz
15742c8a42 mfd: More verbose MFD Kconfig entry
For people to be able to intellingibly decide if they want to enable MFD
drivers or not, we have to give them a much better description of what they
are.
2010-08-12 11:27:23 +02:00
Mark Brown
3cb46ac058 mfd: Staticise ab3550 register access functions
These are now exported via an ops table rather than referenced
directly and so should be staticised.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:22 +02:00
Julia Lawall
e2bde78713 mfd: Fix davinci memory leak
Error handling code following a kmalloc should free the allocated data.

The semantic match that finds the problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,f1,l;
position p1,p2;
expression *ptr != NULL;
@@

x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
(
x->f1 = E
|
 (x->f1 == NULL || ...)
|
 f(...,x->f1,...)
)
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:20 +02:00
Axel Lin
8af5fe3bc5 mfd: properly handle platform_device_add_resources fail in mfd_add_device
platform_device_add_resources may fail, thus add error checking for it.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:19 +02:00
Julia Lawall
25fe24f884 mfd: kzalloc doesn't return ERR_PTR
Use !x rather than IS_ERR(x) to test the result of kzalloc.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,E;
@@

x = \(kmalloc\|kzalloc\|kcalloc\)(...)
... when != x = E
- IS_ERR(x)
+ !x
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:19 +02:00
Linus Walleij
c0d4010e11 mfd: AB8500 mask off irrelevant bits from the SPI message
The registers on the AB8500 are only 8 bits wide, so the content
of the remaining bits is undefined. Let's mask off the undefined
stuff when returning a register in an SPI read.

Acked-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:18 +02:00
Dan Carpenter
eb6e8ddf06 mfd: Fix 88pm860x uninitialized variable and clean up
The original code had a compile warning:
drivers/mfd/88pm860x-core.c:431: warning: ‘ret’ may be used
	uninitialized in this function
It seems like the warning is valid if either pdata or pdata->touch is
NULL.

This patch checks pdata and pdata->touch at the beginning of the
function.  That means everything can be pulled in one indent level.
Now all the statements fit within the 80 character limit.

Also at that point the "use_gpadc" variable isn't needed and removing
it simplifies the logic.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Haojian Zhuang <hzhuang1@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:18 +02:00
Axel Lin
d281b80c46 mfd: Fix memory leak in ab3100_otp_probe
In current implementation, there is a memory leak if ab3100_otp_read fail.
And in the case of ab3100_otp_init_debugfs fail, it does not properly remove
sysfs entries.
This patch properly handle above failure cases.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:17 +02:00
Haojian Zhuang
21f1fc3860 mfd: Fix led resource in 88pm860x
Fix typo error in LED resource of 88pm860x.

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:17 +02:00
Haojian Zhuang
d0f7a6d6d1 mfd: Enable onkey on max8925
Enable onkey feature in max8925 driver.

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-08-12 11:27:16 +02:00
Sam Ravnborg
a64b44ead0 kconfig: fix tristate choice with minimal config
If a minimal config did not specify the value
of all choice values, the resulting configuration
could have wrong values.

Consider following example:
config M
        def_bool y
        option modules
choice
        prompt "choice list"
config A
        tristate "a"
config B
	tristate "b"
endchoice

With a defconfig like this:
CONFIG_M=y
CONFIG_A=y

The resulting configuration would have

    CONFIG_A=m

which was unexpected.

The problem was not not all choice values were set and thus
kconfig calculated a wrong value.

The fix is to set all choice values when we
read a defconfig files.

conf_set_all_new_symbols() is refactored such that
random choice values are now handled by a dedicated function.
And new choice values are set by set_all_choice_values().

This was not the minimal fix, but the fix that resulted
in the most readable code.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reported-by: Arve Hjønnevåg <arve@android.com>
Tested-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-08-12 10:55:02 +02:00
Sam Ravnborg
801690caf1 kconfig: fix savedefconfig for tristate choices
savedefconfig failed to save choice symbols equal to 'y'
for tristate choices.
This resulted in this value being lost.

In particular is fixes an issue where

	make ARCH=avr32 atngw100_defconfig
	make ARCH=avr32 savedefconfig
	cp defconfig arch/avr32/configs/atngw100_defconfig
	make ARCH=avr32 atngw100_defconfig
	diff -u .config .config.old

failed to produce an identical .config.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-08-12 10:55:02 +02:00
Randy Dunlap
cba86f2e20 phylib: available for any speed ethernet
Several gigabit network drivers (SB1250_MAC, TIGON3, FSL, GIANFAR,
UCC_GETH, MV643XX_ETH, XILINX_LL_TEMAC, S6GMAC, STMMAC_ETH, PASEMI_MAC,
and OCTEON_ETHERNET) select PHYLIB.  These drivers are not under
NET_ETHERNET (10/100 mbit), so this warning is generated (long, irrelevant
parts are omitted):

warning: (NET_DSA && NET && EXPERIMENTAL && NET_ETHERNET && !S390 || ... || SB1250_MAC && NETDEVICES && NETDEV_1000 && SIBYTE_SB1xxx_SOC || TIGON3 && NETDEVICES && NETDEV_1000 && PCI || FSL_PQ_MDIO && NETDEVICES && NETDEV_1000 && FSL_SOC || GIANFAR && NETDEVICES && NETDEV_1000 && FSL_SOC || UCC_GETH && NETDEVICES && NETDEV_1000 && QUICC_ENGINE || MV643XX_ETH && NETDEVICES && NETDEV_1000 && (MV64X60 || PPC32 || PLAT_ORION) || XILINX_LL_TEMAC && NETDEVICES && NETDEV_1000 && (PPC || MICROBLAZE) || S6GMAC && NETDEVICES && NETDEV_1000 && XTENSA_VARIANT_S6000 || STMMAC_ETH && NETDEV_1000 && NETDEVICES && CPU_SUBTYPE_ST40 || PASEMI_MAC && NETDEVICES && NETDEV_10000 && PPC_PASEMI && PCI || OCTEON_ETHERNET && STAGING && !STAGING_EXCLUDE_BUILD && CPU_CAVIUM_OCTEON) selects PHYLIB which has unmet direct dependencies (!S390 && NET_ETHERNET)

PHYLIB is used by non-10/100 mbit ethernet drivers, so change the dependencies
to be NETDEVICES instead of NET_ETHERNET.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-11 23:03:50 -07:00
Luca Barbieri
30246557a0 x86, asm: Refactor atomic64_386_32.S to support old binutils and be cleaner
The old code didn't work on binutils 2.12 because setting a symbol to
a register apparently requires a fairly recent version.

This commit refactors the code to use the C preprocessor instead, and
in the process makes the whole code a bit easier to understand.

The object code produced is unchanged as expected.

This fixes kernel bugzilla 16506.

Reported-by: Dieter Stussy <kd6lvw+software@kd6lvw.ampr.org>
Signed-off-by: Luca Barbieri <luca@luca-barbieri.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org> 2.6.35
LKML-Reference: <tip-*@git.kernel.org>
2010-08-11 21:03:28 -07:00
Mike Snitzer
959eb4e559 dm mpath: support discard
Enable discard support in the DM multipath target.

This discard support depends on a few discard-specific fixes to the
block layer's request stacking driver methods.

Discard requests are optional so don't allow a failed discard to trigger
path failures.  If there is a real problem with a given path the
barriers associated with the discard (either before or after the
discard) will cause path failure.  That said, unconditionally passing
discard failures up the stack is not ideal.  This must be fixed once DM
has more information about the nature of the underlying storage failure.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
2010-08-12 04:14:32 +01:00
Mikulas Patocka
7b76ec11fe dm stripe: support discards
The DM core will submit a discard bio to the stripe target for each
stripe in a striped DM device.  The stripe target will determine
stripe-specific portions of the supplied bio to be remapped into
individual (at most 'num_discard_requests' extents).  If a given
stripe-specific discard bio doesn't touch a particular stripe the bio
will be dropped.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:26 +01:00
Mike Snitzer
a79245b3e5 dm: split discard requests on target boundaries
Update __clone_and_map_discard to loop across all targets in a DM
device's table when it processes a discard bio.  If a discard crosses a
target boundary it must be split accordingly.

Update __issue_target_requests and __issue_target_request to allow a
cloned discard bio to have a custom start sector and size.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:24 +01:00
Mikulas Patocka
c96053b767 dm stripe: optimize sector division
Optimize sector division: If the number of stripes is a power of two,
we can do shift and mask instead of division.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:21 +01:00
Mikulas Patocka
65988525ab dm stripe: move sector translation to a function
Move sector to stripe translation into a function.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:14 +01:00
Mike Snitzer
38e1b257fd dm: error return error for discards
Have the error target respond to a discard request with a hard -EIO
rather than fail the request with -EOPNOTSUPP.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:14 +01:00
Mike Snitzer
3fd5d48027 dm delay: support discard
Enable discard support for the delay target.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:13 +01:00
Mike Snitzer
f8facb61b5 dm: zero silently drop discards
Have the zero target silently drop a discard rather than fail the
request with -EOPNOTSUPP.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:12 +01:00
Alasdair G Kergon
b441a262e7 dm: use dm_target_offset macro
Use new dm_target_offset() macro to avoid most references to ti->begin
in dm targets.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:11 +01:00
Mike Snitzer
56a67df766 dm: factor out max_io_len_target_boundary
Split max_io_len_target_boundary out of max_io_len so that the discard
support can make use of it without duplicating max_io_len code.

Avoiding max_io_len's split_io logic enables DM's discard support to
submit the entire discard request to a target.  But discards must still
be split on target boundaries.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:10 +01:00
Mike Snitzer
06a426cee9 dm: use common __issue_target_request for flush and discard support
Rename __flush_target to __issue_target_request now that it is used to
issue both flush and discard requests.

Introduce __issue_target_requests as a convenient wrapper to
__issue_target_request 'num_flush_requests' or 'num_discard_requests'
times per target.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:09 +01:00
Mike Snitzer
5ae89a8720 dm: linear support discard
Allow discards to be passed through to linear mappings if at least one
underlying device supports it.  Discards will be forwarded only to
devices that support them.

A target that supports discards should set num_discard_requests to
indicate how many times each discard request must be submitted to it.

Verify table's underlying devices support discards prior to setting the
associated DM device as capable of discards (via QUEUE_FLAG_DISCARD).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Joe Thornber <thornber@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:08 +01:00
Milan Broz
5ebaee6d29 dm crypt: simplify crypt_ctr
Allocate cipher strings indpendently of struct crypt_config and move
cipher parsing and allocation into a separate function to prepare for
supporting the cryptoapi format e.g. "xts(aes)".

No functional change in this patch.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:07 +01:00
Milan Broz
28513fccf0 dm crypt: simplify crypt_config destruction logic
Use just one label and reuse common destructor for crypt target.

Parse remaining argv arguments in logic order.

Also do not ignore error values from IV init and set key functions.

No functional change in this patch except changed return codes
based on above.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:06 +01:00
Peter Rajnoha
7e507eb643 dm: allow autoloading of dm mod
Add devname:mapper/control and MAPPER_CTRL_MINOR module alias
to support dm-mod module autoloading.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Peter Rajnoha <prajnoha@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:05 +01:00
Mike Snitzer
57cba5d365 dm: rename map_info flush_request to target_request_nr
'target_request_nr' is a more generic name that reflects the fact that
it will be used for both flush and discard support.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:04 +01:00
Will Drewry
26803b9f06 dm ioctl: refactor dm_table_complete
This change unifies the various checks and finalization that occurs on a
table prior to use.  By doing so, it allows table construction without
traversing the dm-ioctl interface.

Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:03 +01:00
Mikulas Patocka
b1d5552838 dm snapshot: implement merge
Implement merge method for the snapshot origin to improve read
performance.

Without merge method, dm asks the upper layers to submit smallest possible
bios --- one page. Submitting such small bios impacts performance negatively
when reading or writing the origin device.

Without this patch, CPU consumption when reading the origin on lvm on md-raid0
was 6 to 12%, with this patch, it drops to 1 to 4%.

Note: in my testing, it actually degraded performance in some settings, I
traced it to Maxtor disks having problems with > 512-sector requests.
Reducing the number of sectors to /sys/block/sd*/queue/max_sectors_kb to
256 fixed the read performance. I think we don't have to care about weird
disks that actually degrade performance because of large requests being
sent to them.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:02 +01:00
Mike Snitzer
4a0b4ddf26 dm: do not initialise full request queue when bio based
Change bio-based mapped devices no longer to have a fully initialized
request_queue (request_fn, elevator, etc).  This means bio-based DM
devices no longer register elevator sysfs attributes ('iosched/' tree
or 'scheduler' other than "none").

In contrast, a request-based DM device will continue to have a full
request_queue and will register elevator sysfs attributes.  Therefore
a user can determine a DM device's type by checking if elevator sysfs
attributes exist.

First allocate a minimalist request_queue structure for a DM device
(needed for both bio and request-based DM).

Initialization of a full request_queue is deferred until it is known
that the DM device is request-based, at the end of the table load
sequence.

Factor DM device's request_queue initialization:
- common to both request-based and bio-based into dm_init_md_queue().
- specific to request-based into dm_init_request_based_queue().

The md->type_lock mutex is used to protect md->queue, in addition to
md->type, during table_load().

A DM device's first table_load will establish the immutable md->type.
But md->queue initialization, based on md->type, may fail at that time
(because blk_init_allocated_queue cannot allocate memory).  Therefore
any subsequent table_load must (re)try dm_setup_md_queue independently of
establishing md->type.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:02 +01:00
Mike Snitzer
a5664dad7e dm ioctl: make bio or request based device type immutable
Determine whether a mapped device is bio-based or request-based when
loading its first (inactive) table and don't allow that to be changed
later.

This patch performs different device initialisation in each of the two
cases.  (We don't think it's necessary to add code to support changing
between the two types.)

Allowed md->type transitions:
  DM_TYPE_NONE to DM_TYPE_BIO_BASED
  DM_TYPE_NONE to DM_TYPE_REQUEST_BASED

We now prevent table_load from replacing the inactive table with a
conflicting type of table even after an explicit table_clear.

Introduce 'type_lock' into the struct mapped_device to protect md->type
and to prepare for the next patch that will change the queue
initialization and allocate memory while md->type_lock is held.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

 drivers/md/dm-ioctl.c    |   15 +++++++++++++++
 drivers/md/dm.c          |   37 ++++++++++++++++++++++++++++++-------
 drivers/md/dm.h          |    5 +++++
 include/linux/dm-ioctl.h |    4 ++--
 4 files changed, 52 insertions(+), 9 deletions(-)
2010-08-12 04:14:01 +01:00
Mikulas Patocka
708e929513 dm: skip second flush on bio unsupported error
When processing barriers, skip the second flush if processing the bio
failed with -EOPNOTSUPP.  This can happen with discard+barrier requests.
If the device doesn't support discard, there would be two useless
SYNCHRONIZE CACHE commands.  The first dm_flush cannot be so easily
optimized out, so we leave it there.

Previously, -EOPNOTSUPP could be received in dec_pending only with empty
barriers and we ignored that error, assuming the device not supporting
cache flushes has cache always consistent.  With the addition of discard
barriers, this -EOPNOTSUPP can also be generated by discards and we
must record it in md->barrier_error for process_barrier.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:14:00 +01:00