Commit 0337966d authored by Dmitry Torokhov's avatar Dmitry Torokhov
Browse files

Merge branch 'next' into for-linus

Prepare input updates for 4.12 merge window.
parents 7c5bb4ac 8a038b83
......@@ -2478,12 +2478,11 @@ S: D-90453 Nuernberg
S: Germany
N: Arnaldo Carvalho de Melo
E: acme@ghostprotocols.net
E: acme@kernel.org
E: arnaldo.melo@gmail.com
E: acme@redhat.com
W: http://oops.ghostprotocols.net:81/blog/
P: 1024D/9224DF01 D5DF E3BB E3C8 BCBB F8AD 841A B6AB 4681 9224 DF01
D: IPX, LLC, DCCP, cyc2x, wl3501_cs, net/ hacks
D: tools/, IPX, LLC, DCCP, cyc2x, wl3501_cs, net/ hacks
S: Brazil
N: Karsten Merker
......
......@@ -270,8 +270,8 @@ m68k/
- directory with info about Linux on Motorola 68k architecture.
mailbox.txt
- How to write drivers for the common mailbox framework (IPC).
md-cluster.txt
- info on shared-device RAID MD cluster.
md/
- directory with info about Linux Software RAID
media/
- info on media drivers: uAPI, kAPI and driver documentation.
memory-barriers.txt
......
What: /sys/block/zram<id>/num_reads
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The num_reads file is read-only and specifies the number of
reads (failed or successful) done on this device.
Now accessible via zram<id>/stat node.
What: /sys/block/zram<id>/num_writes
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The num_writes file is read-only and specifies the number of
writes (failed or successful) done on this device.
Now accessible via zram<id>/stat node.
What: /sys/block/zram<id>/invalid_io
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The invalid_io file is read-only and specifies the number of
non-page-size-aligned I/O requests issued to this device.
Now accessible via zram<id>/io_stat node.
What: /sys/block/zram<id>/failed_reads
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The failed_reads file is read-only and specifies the number of
failed reads happened on this device.
Now accessible via zram<id>/io_stat node.
What: /sys/block/zram<id>/failed_writes
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The failed_writes file is read-only and specifies the number of
failed writes happened on this device.
Now accessible via zram<id>/io_stat node.
What: /sys/block/zram<id>/notify_free
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The notify_free file is read-only. Depending on device usage
scenario it may account a) the number of pages freed because
of swap slot free notifications or b) the number of pages freed
because of REQ_DISCARD requests sent by bio. The former ones
are sent to a swap block device when a swap slot is freed, which
implies that this disk is being used as a swap disk. The latter
ones are sent by filesystem mounted with discard option,
whenever some data blocks are getting discarded.
Now accessible via zram<id>/io_stat node.
What: /sys/block/zram<id>/zero_pages
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The zero_pages file is read-only and specifies number of zero
filled pages written to this disk. No memory is allocated for
such pages.
Now accessible via zram<id>/mm_stat node.
What: /sys/block/zram<id>/orig_data_size
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The orig_data_size file is read-only and specifies uncompressed
size of data stored in this disk. This excludes zero-filled
pages (zero_pages) since no memory is allocated for them.
Unit: bytes
Now accessible via zram<id>/mm_stat node.
What: /sys/block/zram<id>/compr_data_size
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The compr_data_size file is read-only and specifies compressed
size of data stored in this disk. So, compression ratio can be
calculated using orig_data_size and this statistic.
Unit: bytes
Now accessible via zram<id>/mm_stat node.
What: /sys/block/zram<id>/mem_used_total
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The mem_used_total file is read-only and specifies the amount
of memory, including allocator fragmentation and metadata
overhead, allocated for this disk. So, allocator space
efficiency can be calculated using compr_data_size and this
statistic.
Unit: bytes
Now accessible via zram<id>/mm_stat node.
What: /sys/block/zram<id>/mem_used_max
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The mem_used_max file is read/write and specifies the amount
of maximum memory zram have consumed to store compressed data.
For resetting the value, you should write "0". Otherwise,
you could see -EINVAL.
Unit: bytes
Downgraded to write-only node: so it's possible to set new
value only; its current value is stored in zram<id>/mm_stat
node.
What: /sys/block/zram<id>/mem_limit
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The mem_limit file is read/write and specifies the maximum
amount of memory ZRAM can use to store the compressed data.
The limit could be changed in run time and "0" means disable
the limit. No limit is the initial state. Unit: bytes
Downgraded to write-only node: so it's possible to set new
value only; its current value is stored in zram<id>/mm_stat
node.
......@@ -20,3 +20,11 @@ Description: RDMA-CM based connections from HCA <hca> at port <port-num>
will be initiated with this RoCE type as default.
The possible RoCE types are either "IB/RoCE v1" or "RoCE v2".
This parameter has RW access.
What: /config/rdma_cm/<hca>/ports/<port-num>/default_roce_tos
Date: February 7, 2017
KernelVersion: 4.11.0
Description: RDMA-CM QPs from HCA <hca> at port <port-num>
will be created with this TOS as default.
This can be overridden by using the rdma_set_option API.
The possible RoCE TOS values are 0-255.
......@@ -22,41 +22,6 @@ Description:
device. The reset operation frees all the memory associated
with this device.
What: /sys/block/zram<id>/num_reads
Date: August 2010
Contact: Nitin Gupta <ngupta@vflare.org>
Description:
The num_reads file is read-only and specifies the number of
reads (failed or successful) done on this device.
What: /sys/block/zram<id>/num_writes
Date: August 2010
Contact: Nitin Gupta <ngupta@vflare.org>
Description:
The num_writes file is read-only and specifies the number of
writes (failed or successful) done on this device.
What: /sys/block/zram<id>/invalid_io
Date: August 2010
Contact: Nitin Gupta <ngupta@vflare.org>
Description:
The invalid_io file is read-only and specifies the number of
non-page-size-aligned I/O requests issued to this device.
What: /sys/block/zram<id>/failed_reads
Date: February 2014
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The failed_reads file is read-only and specifies the number of
failed reads happened on this device.
What: /sys/block/zram<id>/failed_writes
Date: February 2014
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The failed_writes file is read-only and specifies the number of
failed writes happened on this device.
What: /sys/block/zram<id>/max_comp_streams
Date: February 2014
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
......@@ -73,74 +38,24 @@ Description:
available and selected compression algorithms, change
compression algorithm selection.
What: /sys/block/zram<id>/notify_free
Date: August 2010
Contact: Nitin Gupta <ngupta@vflare.org>
Description:
The notify_free file is read-only. Depending on device usage
scenario it may account a) the number of pages freed because
of swap slot free notifications or b) the number of pages freed
because of REQ_DISCARD requests sent by bio. The former ones
are sent to a swap block device when a swap slot is freed, which
implies that this disk is being used as a swap disk. The latter
ones are sent by filesystem mounted with discard option,
whenever some data blocks are getting discarded.
What: /sys/block/zram<id>/zero_pages
Date: August 2010
Contact: Nitin Gupta <ngupta@vflare.org>
Description:
The zero_pages file is read-only and specifies number of zero
filled pages written to this disk. No memory is allocated for
such pages.
What: /sys/block/zram<id>/orig_data_size
Date: August 2010
Contact: Nitin Gupta <ngupta@vflare.org>
Description:
The orig_data_size file is read-only and specifies uncompressed
size of data stored in this disk. This excludes zero-filled
pages (zero_pages) since no memory is allocated for them.
Unit: bytes
What: /sys/block/zram<id>/compr_data_size
Date: August 2010
Contact: Nitin Gupta <ngupta@vflare.org>
Description:
The compr_data_size file is read-only and specifies compressed
size of data stored in this disk. So, compression ratio can be
calculated using orig_data_size and this statistic.
Unit: bytes
What: /sys/block/zram<id>/mem_used_total
Date: August 2010
Contact: Nitin Gupta <ngupta@vflare.org>
Description:
The mem_used_total file is read-only and specifies the amount
of memory, including allocator fragmentation and metadata
overhead, allocated for this disk. So, allocator space
efficiency can be calculated using compr_data_size and this
statistic.
Unit: bytes
What: /sys/block/zram<id>/mem_used_max
Date: August 2014
Contact: Minchan Kim <minchan@kernel.org>
Description:
The mem_used_max file is read/write and specifies the amount
of maximum memory zram have consumed to store compressed data.
For resetting the value, you should write "0". Otherwise,
you could see -EINVAL.
The mem_used_max file is write-only and is used to reset
the counter of maximum memory zram have consumed to store
compressed data. For resetting the value, you should write
"0". Otherwise, you could see -EINVAL.
Unit: bytes
What: /sys/block/zram<id>/mem_limit
Date: August 2014
Contact: Minchan Kim <minchan@kernel.org>
Description:
The mem_limit file is read/write and specifies the maximum
amount of memory ZRAM can use to store the compressed data. The
limit could be changed in run time and "0" means disable the
limit. No limit is the initial state. Unit: bytes
The mem_limit file is write-only and specifies the maximum
amount of memory ZRAM can use to store the compressed data.
The limit could be changed in run time and "0" means disable
the limit. No limit is the initial state. Unit: bytes
What: /sys/block/zram<id>/compact
Date: August 2015
......
What: /sys/bus/i2c/devices/.../trickle_charge_bypass
Date: Jan 2017
KernelVersion: 4.11
Contact: Enric Balletbo i Serra <eballetbo@gmail.com>
Description: Attribute for enable/disable the trickle charge bypass
The trickle_charge_bypass attribute allows the userspace to
enable/disable the Trickle charge FET bypass.
......@@ -170,6 +170,16 @@ Description:
Has all of the equivalent parameters as per voltageY. Units
after application of scale and offset are m/s^2.
What: /sys/bus/iio/devices/iio:deviceX/in_gravity_x_raw
What: /sys/bus/iio/devices/iio:deviceX/in_gravity_y_raw
What: /sys/bus/iio/devices/iio:deviceX/in_gravity_z_raw
KernelVersion: 4.11
Contact: linux-iio@vger.kernel.org
Description:
Gravity in direction x, y or z (may be arbitrarily assigned
but should match other such assignments on device).
Units after application of scale and offset are m/s^2.
What: /sys/bus/iio/devices/iio:deviceX/in_anglvel_x_raw
What: /sys/bus/iio/devices/iio:deviceX/in_anglvel_y_raw
What: /sys/bus/iio/devices/iio:deviceX/in_anglvel_z_raw
......@@ -805,7 +815,7 @@ Description:
attribute. E.g. if in_voltage0_raw_thresh_rising_value is set to 1200
and in_voltage0_raw_thresh_rising_hysteresis is set to 50. The event
will get activated once in_voltage0_raw goes above 1200 and will become
deactived again once the value falls below 1150.
deactivated again once the value falls below 1150.
What: /sys/.../events/in_accel_x_raw_roc_rising_value
What: /sys/.../events/in_accel_x_raw_roc_falling_value
......@@ -1245,7 +1255,8 @@ Description:
reflectivity of infrared or ultrasound emitted.
Often these sensors are unit less and as such conversion
to SI units is not possible. Higher proximity measurements
indicate closer objects, and vice versa.
indicate closer objects, and vice versa. Units after
application of scale and offset are meters.
What: /sys/.../iio:deviceX/in_illuminance_input
What: /sys/.../iio:deviceX/in_illuminance_raw
......
What: /sys/bus/iio/devices/triggerX/trigger_polarity
KernelVersion: 4.11
Contact: fabrice.gasnier@st.com
Description:
The STM32 ADC can be configured to use external trigger sources
(e.g. timers, pwm or exti gpio). Then, it can be tuned to start
conversions on external trigger by either:
- "rising-edge"
- "falling-edge"
- "both-edges".
Reading returns current trigger polarity.
Writing value before enabling conversions sets trigger polarity.
What: /sys/bus/iio/devices/triggerX/trigger_polarity_available
KernelVersion: 4.11
Contact: fabrice.gasnier@st.com
Description:
List all available trigger_polarity settings.
What /sys/bus/iio/devices/iio:deviceX/sensor_sensitivity
Date: January 2017
KernelVersion: 4.11
Contact: linux-iio@vger.kernel.org
Description:
Show or set the gain boost of the amp, from 0-31 range.
default 31
What /sys/bus/iio/devices/iio:deviceX/sensor_max_range
Date: January 2017
KernelVersion: 4.11
Contact: linux-iio@vger.kernel.org
Description:
Show or set the maximum range between the sensor and the
first object echoed in meters. Default value is 6.020.
This setting limits the time the driver is waiting for a
echo.
Showing the range of available values is represented as the
minimum value, the step and the maximum value, all enclosed
in square brackets.
Example:
[0.043 0.043 11.008]
What: /sys/bus/iio/devices/triggerX/master_mode_available
KernelVersion: 4.11
Contact: benjamin.gaignard@st.com
Description:
Reading returns the list possible master modes which are:
- "reset" : The UG bit from the TIMx_EGR register is used as trigger output (TRGO).
- "enable" : The Counter Enable signal CNT_EN is used as trigger output.
- "update" : The update event is selected as trigger output.
For instance a master timer can then be used as a prescaler for a slave timer.
- "compare_pulse" : The trigger output send a positive pulse when the CC1IF flag is to be set.
- "OC1REF" : OC1REF signal is used as trigger output.
- "OC2REF" : OC2REF signal is used as trigger output.
- "OC3REF" : OC3REF signal is used as trigger output.
- "OC4REF" : OC4REF signal is used as trigger output.
What: /sys/bus/iio/devices/triggerX/master_mode
KernelVersion: 4.11
Contact: benjamin.gaignard@st.com
Description:
Reading returns the current master modes.
Writing set the master mode
What: /sys/bus/iio/devices/triggerX/sampling_frequency
KernelVersion: 4.11
Contact: benjamin.gaignard@st.com
Description:
Reading returns the current sampling frequency.
Writing an value different of 0 set and start sampling.
Writing 0 stop sampling.
What: /sys/class/devfreq-event/event(x)/
Date: January 2017
Contact: Chanwoo Choi <cw00.choi@samsung.com>
Description:
Provide a place in sysfs for the devfreq-event objects.
This allows accessing various devfreq-event specific variables.
The name of devfreq-event object denoted as 'event(x)' which
includes the unique number of 'x' for each devfreq-event object.
What: /sys/class/devfreq-event/event(x)/name
Date: January 2017
Contact: Chanwoo Choi <cw00.choi@samsung.com>
Description:
The /sys/class/devfreq-event/event(x)/name attribute contains
the name of the devfreq-event object. This attribute is
read-only.
What: /sys/class/devfreq-event/event(x)/enable_count
Date: January 2017
Contact: Chanwoo Choi <cw00.choi@samsung.com>
Description:
The /sys/class/devfreq-event/event(x)/enable_count attribute
contains the reference count to enable the devfreq-event
object. If the device is enabled, the value of attribute is
greater than zero.
......@@ -23,6 +23,23 @@ Description:
If the LED does not support different brightness levels, this
should be 1.
What: /sys/class/leds/<led>/brightness_hw_changed
Date: January 2017
KernelVersion: 4.11
Description:
Last hardware set brightness level for this LED. Some LEDs
may be changed autonomously by hardware/firmware. Only LEDs
where this happens and the driver can detect this, will have
this file.
This file supports poll() to detect when the hardware changes
the brightness.
Reading this file will return the last brightness level set
by the hardware, this may be different from the current
brightness. Reading this file when no hw brightness change
event has happened will return an ENODATA error.
What: /sys/class/leds/<led>/trigger
Date: March 2006
KernelVersion: 2.6.17
......
......@@ -62,18 +62,18 @@ Description:
This value may be reset to 0 if the current protocol is altered.
What: /sys/class/rc/rcN/wakeup_protocols
Date: Feb 2014
KernelVersion: 3.15
Date: Feb 2017
KernelVersion: 4.11
Contact: Mauro Carvalho Chehab <m.chehab@samsung.com>
Description:
Reading this file returns a list of available protocols to use
for the wakeup filter, something like:
"rc5 rc6 nec jvc [sony]"
"rc-5 nec nec-x rc-6-0 rc-6-6a-24 [rc-6-6a-32] rc-6-mce"
Note that protocol variants are listed, so "nec", "sony",
"rc-5", "rc-6" have their different bit length encodings
listed if available.
The enabled wakeup protocol is shown in [] brackets.
Writing "+proto" will add a protocol to the list of enabled
wakeup protocols.
Writing "-proto" will remove a protocol from the list of enabled
wakeup protocols.
Only one protocol can be selected at a time.
Writing "proto" will use "proto" for wakeup events.
Writing "none" will disable wakeup.
Write fails with EINVAL if an invalid protocol combination or
......
......@@ -138,3 +138,20 @@ Contact: Mauro Carvalho Chehab <m.chehab@samsung.com>
Description: This attribute file will display what type of memory is
currently on this csrow. Normally, either buffered or
unbuffered memory (for example, Unbuffered-DDR3).
What: /sys/devices/system/edac/mc/mc*/(dimm|rank)*/dimm_ce_count
Date: October 2016
Contact: linux-edac@vger.kernel.org
Description: This attribute file displays the total count of correctable
errors that have occurred on this DIMM. This count is very important
to examine. CEs provide early indications that a DIMM is beginning
to fail. This count field should be monitored for non-zero values
and report such information to the system administrator.
What: /sys/devices/system/edac/mc/mc*/(dimm|rank)*/dimm_ue_count
Date: October 2016
Contact: linux-edac@vger.kernel.org
Description: This attribute file displays the total count of uncorrectable
errors that have occurred on this DIMM. If panic_on_ue is set, this
counter will not have a chance to increment, since EDAC will panic the
system
......@@ -12,3 +12,15 @@ Description: /sys/kernel/iommu_groups/ contains a number of sub-
file if the IOMMU driver has chosen to register a more
common name for the group.
Users:
What: /sys/kernel/iommu_groups/reserved_regions
Date: January 2017
KernelVersion: v4.11
Contact: Eric Auger <eric.auger@redhat.com>
Description: /sys/kernel/iommu_groups/reserved_regions list IOVA
regions that are reserved. Not necessarily all
reserved regions are listed. This is typically used to
output direct-mapped, MSI, non mappable regions. Each
region is described on a single line: the 1st field is
the base IOVA, the second is the end IOVA and the third
field describes the type of the region.
......@@ -2,7 +2,7 @@ What: /sys/devices/platform/hidma-*/chid
/sys/devices/platform/QCOM8061:*/chid
Date: Dec 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Contains the ID of the channel within the HIDMA instance.
It is used to associate a given HIDMA channel with the
......
......@@ -2,7 +2,7 @@ What: /sys/devices/platform/hidma-mgmt*/chanops/chan*/priority
/sys/devices/platform/QCOM8060:*/chanops/chan*/priority
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Contains either 0 or 1 and indicates if the DMA channel is a
low priority (0) or high priority (1) channel.
......@@ -11,7 +11,7 @@ What: /sys/devices/platform/hidma-mgmt*/chanops/chan*/weight
/sys/devices/platform/QCOM8060:*/chanops/chan*/weight
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Contains 0..15 and indicates the weight of the channel among
equal priority channels during round robin scheduling.
......@@ -20,7 +20,7 @@ What: /sys/devices/platform/hidma-mgmt*/chreset_timeout_cycles
/sys/devices/platform/QCOM8060:*/chreset_timeout_cycles
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Contains the platform specific cycle value to wait after a
reset command is issued. If the value is chosen too short,
......@@ -32,7 +32,7 @@ What: /sys/devices/platform/hidma-mgmt*/dma_channels
/sys/devices/platform/QCOM8060:*/dma_channels
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Contains the number of dma channels supported by one instance
of HIDMA hardware. The value may change from chip to chip.
......@@ -41,7 +41,7 @@ What: /sys/devices/platform/hidma-mgmt*/hw_version_major
/sys/devices/platform/QCOM8060:*/hw_version_major
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Version number major for the hardware.
......@@ -49,7 +49,7 @@ What: /sys/devices/platform/hidma-mgmt*/hw_version_minor
/sys/devices/platform/QCOM8060:*/hw_version_minor
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Version number minor for the hardware.
......@@ -57,7 +57,7 @@ What: /sys/devices/platform/hidma-mgmt*/max_rd_xactions
/sys/devices/platform/QCOM8060:*/max_rd_xactions
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Contains a value between 0 and 31. Maximum number of
read transactions that can be issued back to back.
......@@ -69,7 +69,7 @@ What: /sys/devices/platform/hidma-mgmt*/max_read_request
/sys/devices/platform/QCOM8060:*/max_read_request
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Size of each read request. The value needs to be a power
of two and can be between 128 and 1024.
......@@ -78,7 +78,7 @@ What: /sys/devices/platform/hidma-mgmt*/max_wr_xactions
/sys/devices/platform/QCOM8060:*/max_wr_xactions
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Contains a value between 0 and 31. Maximum number of
write transactions that can be issued back to back.
......@@ -91,7 +91,7 @@ What: /sys/devices/platform/hidma-mgmt*/max_write_request
/sys/devices/platform/QCOM8060:*/max_write_request
Date: Nov 2015
KernelVersion: 4.4
Contact: "Sinan Kaya <okaya@cudeaurora.org>"
Contact: "Sinan Kaya <okaya@codeaurora.org>"
Description:
Size of each write request. The value needs to be a power
of two and can be between 128 and 1024.
......@@ -42,7 +42,7 @@ requirements you pass the flag GFP_DMA to kmalloc.
Unfortunately the memory available for ISA DMA is scarce so unless you
allocate the memory during boot-up it's a good idea to also pass
__GFP_REPEAT and __GFP_NOWARN to make the allocater try a bit harder.
__GFP_REPEAT and __GFP_NOWARN to make the allocator try a bit harder.
(This scarcity also means that you should allocate the buffer as
early as possible and not release it until the driver is unloaded.)
......
......@@ -143,3 +143,13 @@ So, this provides a way for drivers to avoid those error messages on calls
where allocation failures are not a problem, and shouldn't bother the logs.
NOTE: At the moment DMA_ATTR_NO_WARN is only implemented on PowerPC.
DMA_ATTR_PRIVILEGED
------------------------------
Some advanced peripherals such as remote processors and GPUs perform
accesses to DMA buffers in both privileged "supervisor" and unprivileged
"user" modes. This attribute is used to indicate to the DMA-mapping
subsystem that the buffer is fully accessible at the elevated privilege