aio: fix uncorrent dirty pages accouting when truncating AIO ring buffer

https://bugzilla.kernel.org/show_bug.cgi?id=86831

Markus reported that when shutting down mysqld (with AIO support,
on a ext3 formatted Harddrive) leads to a negative number of dirty pages
(underrun to the counter). The negative number results in a drastic reduction
of the write performance because the page cache is not used, because the kernel
thinks it is still 2 ^ 32 dirty pages open.

Add a warn trace in __dec_zone_state will catch this easily:

static inline void __dec_zone_state(struct zone *zone, enum
	zone_stat_item item)
{
     atomic_long_dec(&zone->vm_stat[item]);
+    WARN_ON_ONCE(item == NR_FILE_DIRTY &&
	atomic_long_read(&zone->vm_stat[item]) < 0);
     atomic_long_dec(&vm_stat[item]);
}

[   21.341632] ------------[ cut here ]------------
[   21.346294] WARNING: CPU: 0 PID: 309 at include/linux/vmstat.h:242
cancel_dirty_page+0x164/0x224()
[   21.355296] Modules linked in: wutbox_cp sata_mv
[   21.359968] CPU: 0 PID: 309 Comm: kworker/0:1 Not tainted 3.14.21-WuT #80
[   21.366793] Workqueue: events free_ioctx
[   21.370760] [<c0016a64>] (unwind_backtrace) from [<c0012f88>]
(show_stack+0x20/0x24)
[   21.378562] [<c0012f88>] (show_stack) from [<c03f8ccc>]
(dump_stack+0x24/0x28)
[   21.385840] [<c03f8ccc>] (dump_stack) from [<c0023ae4>]
(warn_slowpath_common+0x84/0x9c)
[   21.393976] [<c0023ae4>] (warn_slowpath_common) from [<c0023bb8>]
(warn_slowpath_null+0x2c/0x34)
[   21.402800] [<c0023bb8>] (warn_slowpath_null) from [<c00c0688>]
(cancel_dirty_page+0x164/0x224)
[   21.411524] [<c00c0688>] (cancel_dirty_page) from [<c00c080c>]
(truncate_inode_page+0x8c/0x158)
[   21.420272] [<c00c080c>] (truncate_inode_page) from [<c00c0a94>]
(truncate_inode_pages_range+0x11c/0x53c)
[   21.429890] [<c00c0a94>] (truncate_inode_pages_range) from
[<c00c0f6c>] (truncate_pagecache+0x88/0xac)
[   21.439252] [<c00c0f6c>] (truncate_pagecache) from [<c00c0fec>]
(truncate_setsize+0x5c/0x74)
[   21.447731] [<c00c0fec>] (truncate_setsize) from [<c013b3a8>]
(put_aio_ring_file.isra.14+0x34/0x90)
[   21.456826] [<c013b3a8>] (put_aio_ring_file.isra.14) from
[<c013b424>] (aio_free_ring+0x20/0xcc)
[   21.465660] [<c013b424>] (aio_free_ring) from [<c013b4f4>]
(free_ioctx+0x24/0x44)
[   21.473190] [<c013b4f4>] (free_ioctx) from [<c003d8d8>]
(process_one_work+0x134/0x47c)
[   21.481132] [<c003d8d8>] (process_one_work) from [<c003e988>]
(worker_thread+0x130/0x414)
[   21.489350] [<c003e988>] (worker_thread) from [<c00448ac>]
(kthread+0xd4/0xec)
[   21.496621] [<c00448ac>] (kthread) from [<c000ec18>]
(ret_from_fork+0x14/0x20)
[   21.503884] ---[ end trace 79c4bf42c038c9a1 ]---

The cause is that we set the aio ring file pages as *DIRTY* via SetPageDirty
(bypasses the VFS dirty pages increment) when init, and aio fs uses
*default_backing_dev_info* as the backing dev, which does not disable
the dirty pages accounting capability.
So truncating aio ring file will contribute to accounting dirty pages (VFS
dirty pages decrement), then error occurs.

The original goal is keeping these pages in memory (can not be reclaimed
or swapped) in life-time via marking it dirty. But thinking more, we have
already pinned pages via elevating the page's refcount, which can already
achieve the goal, so the SetPageDirty seems unnecessary.

In order to fix the issue, using the __set_page_dirty_no_writeback instead
of the nop .set_page_dirty, and dropped the SetPageDirty (don't manually
set the dirty flags, don't disable set_page_dirty(), rely on default behaviour).

With the above change, the dirty pages accounting can work well. But as we
known, aio fs is an anonymous one, which should never cause any real write-back,
we can ignore the dirty pages (write back) accounting by disabling the dirty
pages (write back) accounting capability. So we introduce an aio private
backing dev info (disabled the ACCT_DIRTY/WRITEBACK/ACCT_WB capabilities) to
replace the default one.

Reported-by: Markus Königshaus <m.koenigshaus@wut.de>
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
ARM: mvebu: add missing of_node_put() call in coherency.c

There is a missing of_node_put() to decrement the device_node
reference counter after a of_find_matching_node() in coherency_init().

Fixes: 501f928e0097 ("ARM: mvebu: add a coherency_available() call")
Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1414423955-5933-4-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
spi: dw: Fix dynamic speed change.

An IOCTL call that calls spi_setup() and then dw_spi_setup() will
overwrite the persisted last transfer speed. On each transfer, the
SPI speed is compared to the last transfer speed to determine if the
clock divider registers need to be updated (did the speed change?).
This bug was observed with the spidev driver using spi-config to
update the max transfer speed.

This fix: Don't overwrite the persisted last transaction clock speed
when updating the SPI parameters in dw_spi_setup(). On the next
transaction, the new speed won't match the persisted last speed
and the hardware registers will be updated.
On initialization, the persisted last transaction clock
speed will be 0 but will be updated after the first SPI
transaction.

Move zeroed clock divider check into clock change test because
chip->clk_div is zero on startup and would cause a divide-by-zero
error. The calculation was wrong as well (can't support odd #).

Reported-by: Vlastimil Setka <setka@vsis.cz>
Signed-off-by: Vlastimil Setka <setka@vsis.cz>
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
USB: serial: cp210x: add IDs for CEL MeshConnect USB Stick

Signed-off-by: Preston Fick <pffick@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
usb: dwc3: ep0: fix for dead code

commit 6856d30 (usb: dwc3: ep0: return early
on NULL requests) tried to fix a minor corner
case where we could dereference a NULL pointer
but it also ended up introducing some dead code.

Unfortunately, that dead code, if reached, could
end up starving the endpoint request list because
a request would never be given back when it should.

Fix this by moving the check for empty request list
before its first use.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Merge tag 'fixes-for-v3.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-linus

Felipe writes:

usb: fixes for v3.18-rc5

Just one fix here on dwc3 which fixes a minor
bug caused by a fix that went in this v3.18-rc
cycle.

The corner case is minimal as it can only be
reproduced with back-to-back Setup transfers
(without starting data or status phase) by
means of a LeCroy USB Trainer, where we can
generate USB packets any way we like.

Signed-off-by: Felipe Balbi <balbi@ti.com>
iio: Fix IIO_EVENT_CODE_EXTRACT_DIR bit mask

The direction field is set on 7 bits, thus we need to AND it with 0111 111 mask
in order to retrieve it, that is 0x7F, not 0xCF as it is now.

Fixes: ade7ef7ba (staging:iio: Differential channel handling)
Signed-off-by: Cristina Ciocan <cristina.ciocan@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: accel: kxcjk-1013: Fix kxcjk10013_set_range

Currently, we get the new GSEL bits by OR-ing the old values
with the new ones. This only works first time when the old
values are 0.

Startup:
	* GSEL0 = 0, GSEL1 = 0

Set range to 4G: (GSEL0 = 1, GSEL1 = 0)
	* GSEL0 = 0 | 1 = 1
	* GSEL1 = 0 | 0 = 0
	* correct

Change range to 2G: (GSEL0 = 0, GSEL1 = 0)
	* GSEL0 = 1 | 0 = 1
	* GSEL1 = 0 | 0 = 0
	* wrong, GSEL0 should be 0

This has the nice effect that we can use the full scale range,
exported in in_accel_scale_available.

Fixes: a735e3d7f03 (iio: accel: kxcjk-1013: Set adjustable range)
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: adc: men_z188_adc: Add terminating entry for men_z188_ids

The mcb_device_id table is supposed to be zero-terminated.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: gyro: bmg160: Error handling when mode set fails

When mode set fails due to some transient failures, it will atleast
reset the state of runtime usage count and also let the runtime
suspend retry from the driver framework.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: gyro: bmg160: Don't let interrupt mode to be open drain

Change the mode to push/pull type instead of open drain as some
platforms fails to drive the GPIO pin with open drain.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: gyro: bmg160: Send x, y and z motion separately

This chip is capable to identify motion across x, y and z axes. So
send different events.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: gyro: bmg160: Fix iio_event_spec direction

Change event spec direction from
IIO_EV_DIR_RISING | IIO_EV_DIR_FALLING
to
IIO_EV_DIR_EITHER

Suggested-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: accel: bmc150: Error handling when mode set fails

When mode set fails due to some transient failures, it will atleast
reset the state of runtime usage count and also let the runtime
suspend retry from the driver framework.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: accel: bmc150: Send x, y and z motion separately

This chip is capable to identify motion across x, y and z axes. So
send different events.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: accel: bmc150: Fix iio_event_spec direction

Change event spec direction from
IIO_EV_DIR_RISING | IIO_EV_DIR_FALLING
to
IIO_EV_DIR_EITHER

Suggested-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: accel: bmc150: set low default thresholds

Set the threshold to low by default. With this thresholds any movement
on the device with this sensor will generate event.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Input: synaptics - adjust min/max on Thinkpad E540

The LEN2006 Synaptics touchpad (as found in Thinkpad E540) returns wrong
min max values.

touchpad-edge-detector output:
>  Touchpad SynPS/2 Synaptics TouchPad on /dev/input/event6
>  Move one finger around the touchpad to detect the actual edges
>  Kernel says:    x [1472..5674], y [1408..4684]
>  Touchpad sends: x [1264..5675], y [1171..4688]

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88211
Cc: stable@vger.kernel.org
Signed-off-by: Binyamin Sagal <bensagal@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
spi: Fix mapping from vmalloc-ed buffer to scatter list

We can only use page_address on memory that has been mapped using kmap,
when the buffer passed to the SPI has been allocated by vmalloc the page
has not necessarily been mapped through kmap. This means sometimes
page_address will return NULL causing the pointer we pass to sg_set_buf
to be invalid.

As we only call page_address so that we can pass a virtual address to
sg_set_buf which will then immediately call virt_to_page on it, fix this
by calling sg_set_page directly rather then relying on the sg_set_buf
helper.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
clk: at91: usb: fix at91rm9200 round and set rate

at91rm9200_clk_usb_set_rate might fail depending on the requested rate,
because the parent_rate / rate remainder is not necessarily zero.
Moreover, when rounding down the calculated rate we might alter the
divisor calculation and end up with an invalid divisor.

To solve those problems, accept a non zero remainder, and always round
division to the closest result.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: Andreas Henriksson <andreas.henriksson@endian.se>
Tested-by: Andreas Henriksson <andreas.henriksson@endian.se>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>