This time we have some more new material than we used to have during
the last couple of development cycles.
The most important part of it to me is the introduction of a unified
interface for accessing device properties provided by platform
firmware. It works with Device Trees and ACPI in a uniform way and
drivers using it need not worry about where the properties come
from as long as the platform firmware (either DT or ACPI) makes
them available. It covers both devices and "bare" device node
objects without struct device representation as that turns out to
be necessary in some cases. This has been in the works for quite
a few months (and development cycles) and has been approved by
all of the relevant maintainers.
On top of that, some drivers are switched over to the new interface
(at25, leds-gpio, gpio_keys_polled) and some additional changes are
made to the core GPIO subsystem to allow device drivers to manipulate
GPIOs in the "canonical" way on platforms that provide GPIO information
in their ACPI tables, but don't assign names to GPIO lines (in which
case the driver needs to do that on the basis of what it knows about
the device in question). That also has been approved by the GPIO
core maintainers and the rfkill driver is now going to use it.
Second is support for hardware P-states in the intel_pstate driver.
It uses CPUID to detect whether or not the feature is supported by
the processor in which case it will be enabled by default. However,
it can be disabled entirely from the kernel command line if necessary.
Next is support for a platform firmware interface based on ACPI
operation regions used by the PMIC (Power Management Integrated
Circuit) chips on the Intel Baytrail-T and Baytrail-T-CR platforms.
That interface is used for manipulating power resources and for
thermal management: sensor temperature reporting, trip point setting
and so on.
Also the ACPI core is now going to support the _DEP configuration
information in a limited way. Basically, _DEP it supposed to reflect
off-the-hierarchy dependencies between devices which may be very
indirect, like when AML for one device accesses locations in an
operation region handled by another device's driver (usually, the
device depended on this way is a serial bus or GPIO controller).
The support added this time is sufficient to make the ACPI battery
driver work on Asus T100A, but it is general enough to be able to
cover some other use cases in the future.
Finally, we have a new cpufreq driver for the Loongson1B processor.
In addition to the above, there are fixes and cleanups all over the
place as usual and a traditional ACPICA update to a recent upstream
release.
As far as the fixes go, the ACPI LPSS (Low-power Subsystem) driver
for Intel platforms should be able to handle power management of
the DMA engine correctly, the cpufreq-dt driver should interact
with the thermal subsystem in a better way and the ACPI backlight
driver should handle some more corner cases, among other things.
On top of the ACPICA update there are fixes for race conditions
in the ACPICA's interrupt handling code which might lead to some
random and strange looking failures on some systems.
In the cleanups department the most visible part is the series
of commits targeted at getting rid of the CONFIG_PM_RUNTIME
configuration option. That was triggered by a discussion
regarding the generic power domains code during which we realized
that trying to support certain combinations of PM config options
was painful and not really worth it, because nobody would use them
in production anyway. For this reason, we decided to make
CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and that lead to the
conclusion that the latter became redundant and CONFIG_PM could
be used instead of it. The material here makes that replacement
in a major part of the tree, but there will be at least one more
batch of that in the second part of the merge window.
Specifics:
- Support for retrieving device properties information from ACPI
_DSD device configuration objects and a unified device properties
interface for device drivers (and subsystems) on top of that.
As stated above, this works with Device Trees and ACPI and allows
device drivers to be written in a platform firmware (DT or ACPI)
agnostic way. The at25, leds-gpio and gpio_keys_polled drivers
are now going to use this new interface and the GPIO subsystem
is additionally modified to allow device drivers to assign names
to GPIO resources returned by ACPI _CRS objects (in case _DSD is
not present or does not provide the expected data). The changes
in this set are mostly from Mika Westerberg, Rafael J Wysocki,
Aaron Lu, and Darren Hart with some fixes from others (Fabio Estevam,
Geert Uytterhoeven).
- Support for Hardware Managed Performance States (HWP) as described
in Volume 3, section 14.4, of the Intel SDM in the intel_pstate
driver. CPUID is used to detect whether or not the feature is
supported by the processor. If supported, it will be enabled
automatically unless the intel_pstate=no_hwp switch is present in
the kernel command line. From Dirk Brandewie.
- New Intel Broadwell-H ID for intel_pstate (Dirk Brandewie).
- Support for firmware interface based on ACPI operation regions
used by the PMIC chips on the Intel Baytrail-T and Baytrail-T-CR
platforms for power resource control and thermal management
(Aaron Lu).
- Limited support for retrieving off-the-hierarchy dependencies
between devices from ACPI _DEP device configuration objects
and deferred probing support for the ACPI battery driver based
on the _DEP information to make that driver work on Asus T100A
(Lan Tianyu).
- New cpufreq driver for the Loongson1B processor (Kelvin Cheung).
- ACPICA update to upstream revision 20141107 which only affects
tools (Bob Moore).
- Fixes for race conditions in the ACPICA's interrupt handling
code and in the ACPI code related to system suspend and resume
(Lv Zheng and Rafael J Wysocki).
- ACPI core fix for an RCU-related issue in the ioremap() regions
management code that slowed down significantly after CPUs had
been allowed to enter idle states even if they'd had RCU callbakcs
queued and triggered some problems in certain proprietary graphics
driver (and elsewhere). The fix replaces synchronize_rcu() in
that code with synchronize_rcu_expedited() which makes the issue
go away. From Konstantin Khlebnikov.
- ACPI LPSS (Low-Power Subsystem) driver fix to handle power
management of the DMA engine included into the LPSS correctly.
The problem is that the DMA engine doesn't have ACPI PM support
of its own and it simply is turned off when the last LPSS device
having ACPI PM support goes into D3cold. To work around that,
the PM domain used by the ACPI LPSS driver is redesigned so at
least one device with ACPI PM support will be on as long as the
DMA engine is in use. From Andy Shevchenko.
- ACPI backlight driver fix to avoid using it on "Win8-compatible"
systems where it doesn't work and where it was used by default by
mistake (Aaron Lu).
- Assorted minor ACPI core fixes and cleanups from Tomasz Nowicki,
Sudeep Holla, Huang Rui, Hanjun Guo, Fabian Frederick, and
Ashwin Chaugule (mostly related to the upcoming ARM64 support).
- Intel RAPL (Running Average Power Limit) power capping driver
fixes and improvements including new processor IDs (Jacob Pan).
- Generic power domains modification to power up domains after
attaching devices to them to meet the expectations of device
drivers and bus types assuming devices to be accessible at
probe time (Ulf Hansson).
- Preliminary support for controlling device clocks from the
generic power domains core code and modifications of the
ARM/shmobile platform to use that feature (Ulf Hansson).
- Assorted minor fixes and cleanups of the generic power
domains core code (Ulf Hansson, Geert Uytterhoeven).
- Assorted minor fixes and cleanups of the device clocks control
code in the PM core (Geert Uytterhoeven, Grygorii Strashko).
- Consolidation of device power management Kconfig options by making
CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and removing the latter
which is now redundant (Rafael J Wysocki and Kevin Hilman). That
is the first batch of the changes needed for this purpose.
- Core device runtime power management support code cleanup related
to the execution of callbacks (Andrzej Hajda).
- cpuidle ARM support improvements (Lorenzo Pieralisi).
- cpuidle cleanup related to the CPUIDLE_FLAG_TIME_VALID flag and
a new MAINTAINERS entry for ARM Exynos cpuidle (Daniel Lezcano and
Bartlomiej Zolnierkiewicz).
- New cpufreq driver callback (->ready) to be executed when the
cpufreq core is ready to use a given policy object and cpufreq-dt
driver modification to use that callback for cooling device
registration (Viresh Kumar).
- cpufreq core fixes and cleanups (Viresh Kumar, Vince Hsu,
James Geboski, Tomeu Vizoso).
- Assorted fixes and cleanups in the cpufreq-pcc, intel_pstate,
cpufreq-dt, pxa2xx cpufreq drivers (Lenny Szubowicz, Ethan Zhao,
Stefan Wahren, Petr Cvek).
- OPP (Operating Performance Points) framework modification to
allow OPPs to be removed too and update of a few cpufreq drivers
(cpufreq-dt, exynos5440, imx6q, cpufreq) to remove OPPs (added
during initialization) on driver removal (Viresh Kumar).
- Hibernation core fixes and cleanups (Tina Ruchandani and
Markus Elfring).
- PM Kconfig fix related to CPU power management (Pankaj Dubey).
- cpupower tool fix (Prarit Bhargava).
/
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Merge tag 'pm+acpi-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management updates from Rafael Wysocki:
"This time we have some more new material than we used to have during
the last couple of development cycles.
The most important part of it to me is the introduction of a unified
interface for accessing device properties provided by platform
firmware. It works with Device Trees and ACPI in a uniform way and
drivers using it need not worry about where the properties come from
as long as the platform firmware (either DT or ACPI) makes them
available. It covers both devices and "bare" device node objects
without struct device representation as that turns out to be necessary
in some cases. This has been in the works for quite a few months (and
development cycles) and has been approved by all of the relevant
maintainers.
On top of that, some drivers are switched over to the new interface
(at25, leds-gpio, gpio_keys_polled) and some additional changes are
made to the core GPIO subsystem to allow device drivers to manipulate
GPIOs in the "canonical" way on platforms that provide GPIO
information in their ACPI tables, but don't assign names to GPIO lines
(in which case the driver needs to do that on the basis of what it
knows about the device in question). That also has been approved by
the GPIO core maintainers and the rfkill driver is now going to use
it.
Second is support for hardware P-states in the intel_pstate driver.
It uses CPUID to detect whether or not the feature is supported by the
processor in which case it will be enabled by default. However, it
can be disabled entirely from the kernel command line if necessary.
Next is support for a platform firmware interface based on ACPI
operation regions used by the PMIC (Power Management Integrated
Circuit) chips on the Intel Baytrail-T and Baytrail-T-CR platforms.
That interface is used for manipulating power resources and for
thermal management: sensor temperature reporting, trip point setting
and so on.
Also the ACPI core is now going to support the _DEP configuration
information in a limited way. Basically, _DEP it supposed to reflect
off-the-hierarchy dependencies between devices which may be very
indirect, like when AML for one device accesses locations in an
operation region handled by another device's driver (usually, the
device depended on this way is a serial bus or GPIO controller). The
support added this time is sufficient to make the ACPI battery driver
work on Asus T100A, but it is general enough to be able to cover some
other use cases in the future.
Finally, we have a new cpufreq driver for the Loongson1B processor.
In addition to the above, there are fixes and cleanups all over the
place as usual and a traditional ACPICA update to a recent upstream
release.
As far as the fixes go, the ACPI LPSS (Low-power Subsystem) driver for
Intel platforms should be able to handle power management of the DMA
engine correctly, the cpufreq-dt driver should interact with the
thermal subsystem in a better way and the ACPI backlight driver should
handle some more corner cases, among other things.
On top of the ACPICA update there are fixes for race conditions in the
ACPICA's interrupt handling code which might lead to some random and
strange looking failures on some systems.
In the cleanups department the most visible part is the series of
commits targeted at getting rid of the CONFIG_PM_RUNTIME configuration
option. That was triggered by a discussion regarding the generic
power domains code during which we realized that trying to support
certain combinations of PM config options was painful and not really
worth it, because nobody would use them in production anyway. For
this reason, we decided to make CONFIG_PM_SLEEP select
CONFIG_PM_RUNTIME and that lead to the conclusion that the latter
became redundant and CONFIG_PM could be used instead of it. The
material here makes that replacement in a major part of the tree, but
there will be at least one more batch of that in the second part of
the merge window.
Specifics:
- Support for retrieving device properties information from ACPI _DSD
device configuration objects and a unified device properties
interface for device drivers (and subsystems) on top of that. As
stated above, this works with Device Trees and ACPI and allows
device drivers to be written in a platform firmware (DT or ACPI)
agnostic way. The at25, leds-gpio and gpio_keys_polled drivers are
now going to use this new interface and the GPIO subsystem is
additionally modified to allow device drivers to assign names to
GPIO resources returned by ACPI _CRS objects (in case _DSD is not
present or does not provide the expected data). The changes in
this set are mostly from Mika Westerberg, Rafael J Wysocki, Aaron
Lu, and Darren Hart with some fixes from others (Fabio Estevam,
Geert Uytterhoeven).
- Support for Hardware Managed Performance States (HWP) as described
in Volume 3, section 14.4, of the Intel SDM in the intel_pstate
driver. CPUID is used to detect whether or not the feature is
supported by the processor. If supported, it will be enabled
automatically unless the intel_pstate=no_hwp switch is present in
the kernel command line. From Dirk Brandewie.
- New Intel Broadwell-H ID for intel_pstate (Dirk Brandewie).
- Support for firmware interface based on ACPI operation regions used
by the PMIC chips on the Intel Baytrail-T and Baytrail-T-CR
platforms for power resource control and thermal management (Aaron
Lu).
- Limited support for retrieving off-the-hierarchy dependencies
between devices from ACPI _DEP device configuration objects and
deferred probing support for the ACPI battery driver based on the
_DEP information to make that driver work on Asus T100A (Lan
Tianyu).
- New cpufreq driver for the Loongson1B processor (Kelvin Cheung).
- ACPICA update to upstream revision 20141107 which only affects
tools (Bob Moore).
- Fixes for race conditions in the ACPICA's interrupt handling code
and in the ACPI code related to system suspend and resume (Lv Zheng
and Rafael J Wysocki).
- ACPI core fix for an RCU-related issue in the ioremap() regions
management code that slowed down significantly after CPUs had been
allowed to enter idle states even if they'd had RCU callbakcs
queued and triggered some problems in certain proprietary graphics
driver (and elsewhere). The fix replaces synchronize_rcu() in that
code with synchronize_rcu_expedited() which makes the issue go
away. From Konstantin Khlebnikov.
- ACPI LPSS (Low-Power Subsystem) driver fix to handle power
management of the DMA engine included into the LPSS correctly. The
problem is that the DMA engine doesn't have ACPI PM support of its
own and it simply is turned off when the last LPSS device having
ACPI PM support goes into D3cold. To work around that, the PM
domain used by the ACPI LPSS driver is redesigned so at least one
device with ACPI PM support will be on as long as the DMA engine is
in use. From Andy Shevchenko.
- ACPI backlight driver fix to avoid using it on "Win8-compatible"
systems where it doesn't work and where it was used by default by
mistake (Aaron Lu).
- Assorted minor ACPI core fixes and cleanups from Tomasz Nowicki,
Sudeep Holla, Huang Rui, Hanjun Guo, Fabian Frederick, and Ashwin
Chaugule (mostly related to the upcoming ARM64 support).
- Intel RAPL (Running Average Power Limit) power capping driver fixes
and improvements including new processor IDs (Jacob Pan).
- Generic power domains modification to power up domains after
attaching devices to them to meet the expectations of device
drivers and bus types assuming devices to be accessible at probe
time (Ulf Hansson).
- Preliminary support for controlling device clocks from the generic
power domains core code and modifications of the ARM/shmobile
platform to use that feature (Ulf Hansson).
- Assorted minor fixes and cleanups of the generic power domains core
code (Ulf Hansson, Geert Uytterhoeven).
- Assorted minor fixes and cleanups of the device clocks control code
in the PM core (Geert Uytterhoeven, Grygorii Strashko).
- Consolidation of device power management Kconfig options by making
CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and removing the latter
which is now redundant (Rafael J Wysocki and Kevin Hilman). That
is the first batch of the changes needed for this purpose.
- Core device runtime power management support code cleanup related
to the execution of callbacks (Andrzej Hajda).
- cpuidle ARM support improvements (Lorenzo Pieralisi).
- cpuidle cleanup related to the CPUIDLE_FLAG_TIME_VALID flag and a
new MAINTAINERS entry for ARM Exynos cpuidle (Daniel Lezcano and
Bartlomiej Zolnierkiewicz).
- New cpufreq driver callback (->ready) to be executed when the
cpufreq core is ready to use a given policy object and cpufreq-dt
driver modification to use that callback for cooling device
registration (Viresh Kumar).
- cpufreq core fixes and cleanups (Viresh Kumar, Vince Hsu, James
Geboski, Tomeu Vizoso).
- Assorted fixes and cleanups in the cpufreq-pcc, intel_pstate,
cpufreq-dt, pxa2xx cpufreq drivers (Lenny Szubowicz, Ethan Zhao,
Stefan Wahren, Petr Cvek).
- OPP (Operating Performance Points) framework modification to allow
OPPs to be removed too and update of a few cpufreq drivers
(cpufreq-dt, exynos5440, imx6q, cpufreq) to remove OPPs (added
during initialization) on driver removal (Viresh Kumar).
- Hibernation core fixes and cleanups (Tina Ruchandani and Markus
Elfring).
- PM Kconfig fix related to CPU power management (Pankaj Dubey).
- cpupower tool fix (Prarit Bhargava)"
* tag 'pm+acpi-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (120 commits)
i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c
dmaengine / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
tools: cpupower: fix return checks for sysfs_get_idlestate_count()
drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
e1000e / igb / PM: Eliminate CONFIG_PM_RUNTIME
MMC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
MFD / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
misc / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
media / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
input / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
leds: leds-gpio: Fix multiple instances registration without 'label' property
iio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
hsi / OMAP / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
i2c-hid / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
drm / exynos / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
gpio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
hwrandom / exynos / PM: Use CONFIG_PM in #ifdef
block / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
USB / PM: Drop CONFIG_PM_RUNTIME from the USB core
PM: Merge the SET*_RUNTIME_PM_OPS() macros
...
This patch is the usual mix of driver updates (srp, ipr, scsi_debug, NCR5380,
fnic, 53c974, ses, wd719x, hpsa, megaraid_sas). Of those, wd7a9x is new and
53c974 is a rewrite of the old tmscsim driver and the extensive work by Finn
Thain rewrites all the NCR5380 based drivers. There's also extensive
infrastructure updates: a new logging infrastructure for sense information and
a rewrite of the tagged command queue API and an assortment of minor updates.
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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Merge tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This patch is the usual mix of driver updates (srp, ipr, scsi_debug,
NCR5380, fnic, 53c974, ses, wd719x, hpsa, megaraid_sas).
Of those, wd7a9x is new and 53c974 is a rewrite of the old tmscsim
driver and the extensive work by Finn Thain rewrites all the NCR5380
based drivers.
There's also extensive infrastructure updates: a new logging
infrastructure for sense information and a rewrite of the tagged
command queue API and an assortment of minor updates"
* tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (183 commits)
scsi: set fmt to NULL scsi_extd_sense_format() by default
libsas: remove task_collector mode
wd719x: remove dma_cache_sync call
scsi_debug: add Report supported opcodes+tmfs; Compare and write
scsi_debug: change SCSI command parser to table driven
scsi_debug: add Capacity Changed Unit Attention
scsi_debug: append inject error flags onto scsi_cmnd object
scsi_debug: pinpoint invalid field in sense data
wd719x: Add firmware documentation
wd719x: Introduce Western Digital WD7193/7197/7296 PCI SCSI card driver
eeprom-93cx6: Add (read-only) support for 8-bit mode
esas2r: fix an oversight in setting return value
esas2r: fix an error path in esas2r_ioctl_handler
esas2r: fir error handling in do_fm_api
scsi: add SPC-3 command definitions
scsi: rename SERVICE_ACTION_IN to SERVICE_ACTION_IN_16
scsi: remove scsi_driver owner field
scsi: move scsi_dispatch_cmd to scsi_lib.c
scsi: stop passing a gfp_mask argument down the command setup path
scsi: remove scsi_next_command
...
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so #ifdef blocks
depending on CONFIG_PM_RUNTIME may now be changed to depend on
CONFIG_PM.
Replace CONFIG_PM_RUNTIME with CONFIG_PM in the block device core.
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
bio integrity handling is broken on a system with LVM layered atop a
DIF/DIX SCSI drive because device mapper clones the bio, modifies the
clone, and sends the clone to the lower layers for processing.
However, the clone bio has bi_vcnt == 0, which means that when the sd
driver calls bio_integrity_process to attach DIX data, the
for_each_segment_all() call (which uses bi_vcnt) returns immediately
and random garbage is sent to the disk on a disk write. The disk of
course returns an error.
Therefore, teach bio_integrity_process() to use bio_for_each_segment()
to iterate the bio_vecs, since the per-bio iterator tracks which
bio_vecs are associated with that particular bio. The integrity
handling code is effectively part of the "driver" (it's not the bio
owner), so it must use the correct iterator function.
v2: Fix a compiler warning about abandoned local variables. This
patch supersedes "block: bio_integrity_process uses wrong bio_vec
iterator". Patch applies against 3.18-rc6.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
SPC-3 defines SERVICE ACTION IN(12) and SERVICE ACTION IN(16).
So rename SERVICE_ACTION_IN to SERVICE_ACTION_IN_16 to be
consistent with SPC and to allow for better distinction.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Tested-by: Robert Elliott <elliott@hp.com>
Reviewed-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Currently scsi piggy backs on the block layer to define the concept
of a tagged command. But we want to be able to have block-level host-wide
tags assigned even for untagged commands like the initial INQUIRY, so add
a new SCSI-level flag for commands that are tagged at the scsi level, so
that even commands without that set can have tags assigned to them. Note
that this alredy is the case for the blk-mq code path, and this just lets
the old path catch up with it.
We also set this flag based upon sdev->simple_tags instead of the block
queue flag, so that it is entirely independent of the block layer tagging,
and thus always correct even if a driver doesn't use block level tagging
yet.
Also remove the old blk_rq_tagged; it was only used by SCSI drivers, and
removing it forces them to look for the proper replacement.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
The queuecommand() callback functions in SCSI low-level drivers
need to know which hardware context has been selected by the
block layer. Since this information is not available in the
request structure, and since passing the hctx pointer directly to
the queuecommand callback function would require modification of
all SCSI LLDs, add a function to the block layer that allows to
query the hardware context index.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
For cloned bio, bio->bi_vcnt can't be used at all, and we
have resort to bio_segments() to figure out how many
segment there are in the bio.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Fix an error path in SCSI_IOCTL_SEND_COMMAND that calls
blk_put_request(rq) on an invalid IS_ERR(rq) pointer.
Fixes: a492f07545 ("block,scsi: fixup blk_get_request dead queue scenarios")
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
q->mq_usage_counter is a percpu_ref which is killed and drained when
the queue is frozen. On a CPU hotplug event, blk_mq_queue_reinit()
which involves freezing the queue is invoked on all existing queues.
Because percpu_ref killing and draining involve a RCU grace period,
doing the above on one queue after another may take a long time if
there are many queues on the system.
This patch splits out initiation of freezing and waiting for its
completion, and updates blk_mq_queue_reinit_notify() so that the
queues are frozen in parallel instead of one after another. Note that
freezing and unfreezing are moved from blk_mq_queue_reinit() to
blk_mq_queue_reinit_notify().
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Priority of a merged request is computed by ioprio_best(). If one of the
requests has undefined priority (IOPRIO_CLASS_NONE) and another request
has priority from IOPRIO_CLASS_BE, the function will return the
undefined priority which is wrong. Fix the function to properly return
priority of a request with the defined priority.
Fixes: d58cdfb89c
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
while compiling integer err was showing as a set but unused variable.
elevator_init_fn can be either cfq_init_queue or deadline_init_queue
or noop_init_queue.
all three of these functions are returning -ENOMEM if they fail to
allocate the queue.
so we should actually be returning the error code rather than
returning 0 always.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
When sg_scsi_ioctl() fails to prepare request to submit in
blk_rq_map_kern() we jump to a label where we just end up copying
(luckily zeroed-out) kernel buffer to userspace instead of reporting
error. Fix the problem by jumping to the right label.
CC: Jens Axboe <axboe@kernel.dk>
CC: linux-scsi@vger.kernel.org
CC: stable@vger.kernel.org
Coverity-id: 1226871
Signed-off-by: Jan Kara <jack@suse.cz>
Fixed up the, now unused, out label.
Signed-off-by: Jens Axboe <axboe@fb.com>
The problem is introduced by commit 764f612c6c3c231b(blk-merge:
don't compute bi_phys_segments from bi_vcnt for cloned bio),
and merge is needed if number of current segment isn't less than
max segments.
Strictly speaking, bio->bi_vcnt shouldn't be used here since
it may not be accurate in cases of both cloned bio or bio cloned
from, but bio_segments() is a bit expensive, and bi_vcnt is still
the biggest number, so the approach should work.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull core block layer changes from Jens Axboe:
"This is the core block IO pull request for 3.18. Apart from the new
and improved flush machinery for blk-mq, this is all mostly bug fixes
and cleanups.
- blk-mq timeout updates and fixes from Christoph.
- Removal of REQ_END, also from Christoph. We pass it through the
->queue_rq() hook for blk-mq instead, freeing up one of the request
bits. The space was overly tight on 32-bit, so Martin also killed
REQ_KERNEL since it's no longer used.
- blk integrity updates and fixes from Martin and Gu Zheng.
- Update to the flush machinery for blk-mq from Ming Lei. Now we
have a per hardware context flush request, which both cleans up the
code should scale better for flush intensive workloads on blk-mq.
- Improve the error printing, from Rob Elliott.
- Backing device improvements and cleanups from Tejun.
- Fixup of a misplaced rq_complete() tracepoint from Hannes.
- Make blk_get_request() return error pointers, fixing up issues
where we NULL deref when a device goes bad or missing. From Joe
Lawrence.
- Prep work for drastically reducing the memory consumption of dm
devices from Junichi Nomura. This allows creating clone bio sets
without preallocating a lot of memory.
- Fix a blk-mq hang on certain combinations of queue depths and
hardware queues from me.
- Limit memory consumption for blk-mq devices for crash dump
scenarios and drivers that use crazy high depths (certain SCSI
shared tag setups). We now just use a single queue and limited
depth for that"
* 'for-3.18/core' of git://git.kernel.dk/linux-block: (58 commits)
block: Remove REQ_KERNEL
blk-mq: allocate cpumask on the home node
bio-integrity: remove the needless fail handle of bip_slab creating
block: include func name in __get_request prints
block: make blk_update_request print prefix match ratelimited prefix
blk-merge: don't compute bi_phys_segments from bi_vcnt for cloned bio
block: fix alignment_offset math that assumes io_min is a power-of-2
blk-mq: Make bt_clear_tag() easier to read
blk-mq: fix potential hang if rolling wakeup depth is too high
block: add bioset_create_nobvec()
block: use bio_clone_fast() in blk_rq_prep_clone()
block: misplaced rq_complete tracepoint
sd: Honor block layer integrity handling flags
block: Replace strnicmp with strncasecmp
block: Add T10 Protection Information functions
block: Don't merge requests if integrity flags differ
block: Integrity checksum flag
block: Relocate bio integrity flags
block: Add a disk flag to block integrity profile
block: Add prefix to block integrity profile flags
...
All other allocs are done on the specific node, somehow the
cpumask for hw queue runs was missed. Fix that by using
zalloc_cpumask_var_node() in blk_mq_init_queue().
Signed-off-by: Jens Axboe <axboe@fb.com>
bip_slab is created with SLAB_PANIC, so the fail handler is unneeded.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
In __get_request calls to printk_ratelimited, include the function name so
the callbacks suppressed message matches the messages that are printed,
and add "dev" before the device name so it matches other block layer
messages.
Signed-off-by: Robert Elliott <elliott@hp.com>
Reviewed-by: Webb Scales <webbnh@hp.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull percpu updates from Tejun Heo:
"A lot of activities on percpu front. Notable changes are...
- percpu allocator now can take @gfp. If @gfp doesn't contain
GFP_KERNEL, it tries to allocate from what's already available to
the allocator and a work item tries to keep the reserve around
certain level so that these atomic allocations usually succeed.
This will replace the ad-hoc percpu memory pool used by
blk-throttle and also be used by the planned blkcg support for
writeback IOs.
Please note that I noticed a bug in how @gfp is interpreted while
preparing this pull request and applied the fix 6ae833c7fe
("percpu: fix how @gfp is interpreted by the percpu allocator")
just now.
- percpu_ref now uses longs for percpu and global counters instead of
ints. It leads to more sparse packing of the percpu counters on
64bit machines but the overhead should be negligible and this
allows using percpu_ref for refcnting pages and in-memory objects
directly.
- The switching between percpu and single counter modes of a
percpu_ref is made independent of putting the base ref and a
percpu_ref can now optionally be initialized in single or killed
mode. This allows avoiding percpu shutdown latency for cases where
the refcounted objects may be synchronously created and destroyed
in rapid succession with only a fraction of them reaching fully
operational status (SCSI probing does this when combined with
blk-mq support). It's also planned to be used to implement forced
single mode to detect underflow more timely for debugging.
There's a separate branch percpu/for-3.18-consistent-ops which cleans
up the duplicate percpu accessors. That branch causes a number of
conflicts with s390 and other trees. I'll send a separate pull
request w/ resolutions once other branches are merged"
* 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (33 commits)
percpu: fix how @gfp is interpreted by the percpu allocator
blk-mq, percpu_ref: start q->mq_usage_counter in atomic mode
percpu_ref: make INIT_ATOMIC and switch_to_atomic() sticky
percpu_ref: add PERCPU_REF_INIT_* flags
percpu_ref: decouple switching to percpu mode and reinit
percpu_ref: decouple switching to atomic mode and killing
percpu_ref: add PCPU_REF_DEAD
percpu_ref: rename things to prepare for decoupling percpu/atomic mode switch
percpu_ref: replace pcpu_ prefix with percpu_
percpu_ref: minor code and comment updates
percpu_ref: relocate percpu_ref_reinit()
Revert "blk-mq, percpu_ref: implement a kludge for SCSI blk-mq stall during probe"
Revert "percpu: free percpu allocation info for uniprocessor system"
percpu-refcount: make percpu_ref based on longs instead of ints
percpu-refcount: improve WARN messages
percpu: fix locking regression in the failure path of pcpu_alloc()
percpu-refcount: add @gfp to percpu_ref_init()
proportions: add @gfp to init functions
percpu_counter: add @gfp to percpu_counter_init()
percpu_counter: make percpu_counters_lock irq-safe
...
It isn't correct to figure out req->bi_phys_segments from bio->bi_vcnt
if the bio is cloned.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Tested-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The math in both blk_stack_limits() and queue_limit_alignment_offset()
assume that a block device's io_min (aka minimum_io_size) is always a
power-of-2. Fix the math such that it works for non-power-of-2 io_min.
This issue (of alignment_offset != 0) became apparent when testing
dm-thinp with a thinp blocksize that matches a RAID6 stripesize of
1280K. Commit fdfb4c8c1 ("dm thin: set minimum_io_size to pool's data
block size") unlocked the potential for alignment_offset != 0 due to
the dm-thin-pool's io_min possibly being a non-power-of-2.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
We currently divide the queue depth by 4 as our batch wakeup
count, but we split the wakeups over BT_WAIT_QUEUES number of
wait queues. This defaults to 8. If the product of the resulting
batch wake count and BT_WAIT_QUEUES is higher than the device
queue depth, we can get into a situation where a task goes to
sleep waiting for a request, but never gets woken up.
Reported-by: Bart Van Assche <bvanassche@acm.org>
Fixes: 4bb659b156
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
Users of bio_clone_fast() do not want bios with their own bvecs.
Allocating a bvec mempool as part of the bioset intended for such users
is a waste of memory.
bioset_create_nobvec() creates a bioset that doesn't have the bvec
mempool.
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Request cloning clones bios in the request to track the completion
of each bio.
For that purpose, we can use bio_clone_fast() instead of bio_clone()
to avoid unnecessary allocation and copy of bvecs.
This patch reduces memory footprint of request-based device-mapper
(about 1-4KB for each request) and is a preparation for further
reduction of memory usage by removing unused bvec mempool.
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The rq_complete tracepoint was never issued for empty requests,
causing the resulting blktrace information to never show any
completion for those request.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
The kernel used to contain two functions for length-delimited,
case-insensitive string comparison, strnicmp with correct semantics
and a slightly buggy strncasecmp. The latter is the POSIX name, so
strnicmp was renamed to strncasecmp, and strnicmp made into a wrapper
for the new strncasecmp to avoid breaking existing users.
To allow the compat wrapper strnicmp to be removed at some point in
the future, and to avoid the extra indirection cost, do
s/strnicmp/strncasecmp/g.
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
The T10 Protection Information format is also used by some devices that
do not go through the SCSI layer (virtual block devices, NVMe). Relocate
the relevant functions to a block layer library that can be used without
involving SCSI.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
We'd occasionally merge requests with conflicting integrity flags.
Introduce a merge helper which checks that the requests have compatible
integrity payloads.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Make the choice of checksum a per-I/O property by introducing a flag
that can be inspected by the SCSI layer. There are several reasons for
this:
1. It allows us to switch choice of checksum without unloading and
reloading the HBA driver.
2. During error recovery we need to be able to tell the HBA that
checksums read from disk should not be verified and converted to IP
checksums.
3. For error injection purposes we need to be able to write a bad guard
tag to storage. Since the storage device only supports T10 CRC we
need to be able to disable IP checksum conversion on the HBA.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Move flags affecting the integrity code out of the bio bi_flags and into
the block integrity payload.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
So far we have relied on the app tag size to determine whether a disk
has been formatted with T10 protection information or not. However, not
all target devices provide application tag storage.
Add a flag to the block integrity profile that indicates whether the
disk has been formatted with protection information.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@dev.mellanox.co.il>
Signed-off-by: Jens Axboe <axboe@fb.com>
Add a BLK_ prefix to the integrity profile flags. Also rename the flags
to be more consistent with the generate/verify terminology in the rest
of the integrity code.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Instead of the "operate" parameter we pass in a seed value and a pointer
to a function that can be used to process the integrity metadata. The
generation function is changed to have a return value to fit into this
scheme.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Now that the protection interval has been detached from the sector size
we need to be able to handle sizes that are different from 4K and
512. Make the interval calculation generic.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The protection interval is not necessarily tied to the logical block
size of a block device. Stop using the terms "sector" and "sectors".
Going forward we will use the term "seed" to describe the initial
reference tag value for a given I/O. "Interval" will be used to describe
the portion of the data buffer that a given piece of protection
information is associated with.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
bip_buf is not really needed so we can remove it.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
None of the filesystems appear interested in using the integrity tagging
feature. Potentially because very few storage devices actually permit
using the application tag space.
Remove the tagging functions.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
For commands like REQ_COPY we need a way to pass extra information along
with each bio. Like integrity metadata this information must be
available at the bottom of the stack so bi_private does not suffice.
Rename the existing bi_integrity field to bi_special and make it a union
so we can have different bio extensions for each class of command.
We previously used bi_integrity != NULL as a way to identify whether a
bio had integrity metadata or not. Introduce a REQ_INTEGRITY to be the
indicator now that bi_special can contain different things.
In addition, bio_integrity(bio) will now return a pointer to the
integrity payload (when applicable).
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
bdev_integrity_enabled() is only used by bio_integrity_enabled().
Combine these two functions.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch supports to run one single flush machinery for
each blk-mq dispatch queue, so that:
- current init_request and exit_request callbacks can
cover flush request too, then the buggy copying way of
initializing flush request's pdu can be fixed
- flushing performance gets improved in case of multi hw-queue
In fio sync write test over virtio-blk(4 hw queues, ioengine=sync,
iodepth=64, numjobs=4, bs=4K), it is observed that througput gets
increased a lot over my test environment:
- throughput: +70% in case of virtio-blk over null_blk
- throughput: +30% in case of virtio-blk over SSD image
The multi virtqueue feature isn't merged to QEMU yet, and patches for
the feature can be found in below tree:
git://kernel.ubuntu.com/ming/qemu.git v2.1.0-mq.4
And simply passing 'num_queues=4 vectors=5' should be enough to
enable multi queue(quad queue) feature for QEMU virtio-blk.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch adds 'blk_mq_ctx' parameter to blk_get_flush_queue(),
so that this function can find the corresponding blk_flush_queue
bound with current mq context since the flush queue will become
per hw-queue.
For legacy queue, the parameter can be simply 'NULL'.
For multiqueue case, the parameter should be set as the context
from which the related request is originated. With this context
info, the hw queue and related flush queue can be found easily.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Just figuring out flush queue at the entry of kicking off flush
machinery and request's completion handler, then pass it through.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Now mission of the two helpers is over, and just call
blk_alloc_flush_queue() and blk_free_flush_queue() directly.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch introduces 'struct blk_flush_queue' and puts all
flush machinery related fields into this structure, so that
- flush implementation details aren't exposed to driver
- it is easy to convert to per dispatch-queue flush machinery
This patch is basically a mechanical replacement.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch trys to use local variable to access flush request,
so that we can convert to per-queue flush machinery a bit easier.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Linus Torvalds