SError used to be cleared in ->postreset. This has small hotplug race
condition. If a device is plugged in after reset is complete but
postreset hasn't run yet, its hotplug event gets lost when SError is
cleared. This patch makes sata_link_resume() clear SError. This
kills the race condition and makes a lot of sense as some PMP and host
PHYs don't work properly without SError cleared.
This change makes sata_pmp_std_{pre|post}_reset()'s unnecessary as
they become identical to ata_std counterparts. It also simplifies
sata_pmp_hardreset() and ahci_vt8251_hardreset().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Implement sata_std_hardreset(), which simply wraps around
sata_link_hardreset(). sata_std_hardreset() becomes new standard
hardreset method for sata_port_ops and sata_sff_hardreset() moves from
ata_base_port_ops to ata_sff_port_ops, which is where it really
belongs.
ata_is_builtin_hardreset() is added so that both
ata_std_error_handler() and ata_sff_error_handler() skip both builtin
hardresets if SCR isn't accessible.
piix_sidpr_hardreset() in ata_piix.c is identical to
sata_std_hardreset() in functionality and got replaced with the
standard function.
Signed-off-by: Tejun Heo <htejun@gmail.com>
sata_sff_hardreset() contains link readiness wait logic which isn't
SFF specific. Move that part into sata_link_hardreset(), which now
takes two more parameters - @online and @check_ready. Both are
optional. The former is out parameter for link onlineness after
reset. The latter is used to wait for link readiness after hardreset.
Users of sata_link_hardreset() is updated to use new funtionality and
ahci_hardreset() is updated to use sata_link_hardreset() instead of
sata_sff_hardreset(). This doesn't really cause any behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Factor out waiting logic (which is common to all ATA controllers) from
ata_sff_wait_ready() into ata_wait_ready(). ata_wait_ready() takes
@check_ready function pointer and uses it to poll for readiness. This
allows non-SFF controllers to use ata_wait_ready() to wait for link
readiness.
This patch also implements ata_wait_after_reset() - generic version of
ata_sff_wait_after_reset() - using ata_wait_ready().
ata_sff_wait_ready() is reimplemented using ata_wait_ready() and
ata_sff_check_ready(). Functionality remains the same.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Previously, post-softreset readiness is waited as follows.
1. ata_sff_wait_after_reset() waits for 150ms and then for
ATA_TMOUT_FF_WAIT if status is 0xff and other conditions meet.
2. ata_bus_softreset() finishes with -ENODEV if status is still 0xff.
If not, continue to #3.
3. ata_bus_post_reset() waits readiness of dev0 and/or dev1 depending
on devmask using ata_sff_wait_ready().
And for post-hardreset readiness,
1. ata_sff_wait_after_reset() waits for 150ms and then for
ATA_TMOUT_FF_WAIT if status is 0xff and other conditions meet.
2. sata_sff_hardreset waits for device readiness using
ata_sff_wait_ready().
This patch merges and unifies post-reset readiness waits into
ata_sff_wait_ready() and ata_sff_wait_after_reset().
ATA_TMOUT_FF_WAIT handling is merged into ata_sff_wait_ready(). If TF
status is 0xff, link status is unknown and the port is SATA, it will
continue polling till ATA_TMOUT_FF_WAIT.
ata_sff_wait_after_reset() is updated to perform the following steps.
1. waits for 150ms.
2. waits for dev0 readiness using ata_sff_wait_ready(). Note that
this is done regardless of devmask, as ata_sff_wait_ready() handles
0xff status correctly, this preserves the original behavior except
that it may wait longer after softreset if link is online but
status is 0xff. This behavior change is very unlikely to cause any
actual difference and is intended. It brings softreset behavior to
that of hardreset.
3. waits for dev1 readiness just the same way ata_bus_post_reset() did.
Now both soft and hard resets call ata_sff_wait_after_reset() after
reset to wait for readiness after resets. As
ata_sff_wait_after_reset() contains calls to ->sff_dev_select(),
explicit call near the end of sata_sff_hardreset() is removed.
This change makes reset implementation simpler and more consistent.
While at it, make the magical 150ms wait post-reset wait duration a
constant and ata_sff_wait_ready() and ata_sff_wait_after_reset() take
@link instead of @ap. This is to make them consistent with other
reset helpers and ease core changes.
pata_scc is updated accordingly.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Separate out generic ATA portion from ata_sff_postreset() into
ata_std_postreset() and implement ata_sff_postreset() using the std
version.
ata_base_port_ops now has ata_std_postreset() for its postreset and
ata_sff_port_ops overrides it to ata_sff_postreset().
This change affects pdc_adma, ahci, sata_fsl and sata_sil24. pdc_adma
now specifies postreset to ata_sff_postreset() explicitly. sata_fsl
and sata_sil24 now use ata_std_postreset() which makes no difference
to them. ahci now calls ata_std_postreset() from its own postreset
method, which causes no behavior difference.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Separate out generic ATA portion from ata_sff_prereset() into
ata_std_prereset() and implement ata_sff_prereset() using the std
version. Waiting for device readiness is the only SFF specific part.
ata_base_port_ops now has ata_std_prereset() for its prereset and
ata_sff_port_ops overrides it to ata_sff_prereset(). This change can
affect pdc_adma, ahci, sata_fsl and sata_sil24. pdc_adma implements
its own prereset using ata_sff_prereset() and the rest has hardreset
and thus are unaffected by this change.
This change reflects real world situation. There is no generic way to
wait for device readiness for non-SFF controllers and some of them
don't have any mechanism for that. Non-sff drivers which don't have
hardreset should wrap ata_std_prereset() and wait for device readiness
itself but there's no such driver now and isn't likely to be popular
in the future either.
Signed-off-by: Tejun Heo <htejun@gmail.com>
->sff_irq_clear() is called only from SFF interrupt handler, so there
is no reason to initialize it for non-SFF controllers. Also,
ata_sff_irq_clear() can handle both BMDMA and non-BMDMA SFF
controllers.
This patch kills ata_noop_irq_clear() and removes it from base
port_ops and sets ->sff_irq_clear to ata_sff_irq_clear() in sff
port_ops instead of bmdma port_ops.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Add sff_ prefix to SFF specific port ops.
This rename is in preparation of separating SFF support out of libata
core layer. This patch strictly renames ops and doesn't introduce any
behavior difference.
Signed-off-by: Tejun Heo <htejun@gmail.com>
SFF functions have confusing names. Some have sff prefix, some have
bmdma, some std, some pci and some none. Unify the naming by...
* SFF functions which are common to both BMDMA and non-BMDMA are
prefixed with ata_sff_.
* SFF functions which are specific to BMDMA are prefixed with
ata_bmdma_.
* SFF functions which are specific to PCI but apply to both BMDMA and
non-BMDMA are prefixed with ata_pci_sff_.
* SFF functions which are specific to PCI and BMDMA are prefixed with
ata_pci_bmdma_.
* Drop generic prefixes from LLD specific routines. For example,
bfin_std_dev_select -> bfin_dev_select.
The following renames are noteworthy.
ata_qc_issue_prot() -> ata_sff_qc_issue()
ata_pci_default_filter() -> ata_bmdma_mode_filter()
ata_dev_try_classify() -> ata_sff_dev_classify()
This rename is in preparation of separating SFF support out of libata
core layer. This patch strictly renames functions and doesn't
introduce any behavior difference.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Currently whether a command should be retried after failure is
determined inside ata_eh_finish(). Add ATA_QCFLAG_RETRY and move the
logic into ata_eh_autopsy(). This makes things clearer and helps
extending retry determination logic.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_chk_status() just calls ops->check_status and it only adds
confusion with other status functions. Kill it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_pci_default_filter() doesn't really have anything to do with PCI.
It's generally applicable to BMDMA controllers. Move it out of
CONFIG_PCI.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* Move SFF related functions from libata-core.c to libata-sff.c.
ata_[bmdma_]sff_port_ops, ata_devchk(), ata_dev_try_classify(),
ata_std_dev_select(), ata_tf_to_host(), ata_busy_sleep(),
ata_wait_after_reset(), ata_wait_ready(), ata_bus_post_reset(),
ata_bus_softreset(), ata_bus_reset(), ata_std_softreset(),
sata_std_hardreset(), ata_fill_sg(), ata_fill_sg_dumb(),
ata_qc_prep(), ata_dump_qc_prep(), ata_data_xfer(),
ata_data_xfer_noirq(), ata_pio_sector(), ata_pio_sectors(),
atapi_send_cdb(), __atapi_pio_bytes(), atapi_pio_bytes(),
ata_hsm_ok_in_wq(), ata_hsm_qc_complete(), ata_hsm_move(),
ata_pio_task(), ata_qc_issue_prot(), ata_host_intr(),
ata_interrupt(), ata_std_ports()
* Make ata_pio_queue_task() global as it's now called from
libata-sff.c.
* Move SFF related stuff in include/linux/libata.h and
drivers/ata/libata.h into one place. While at it, move timing
constants into the global enum definition and fortify comments a
bit.
This patch strictly moves stuff around and as such doesn't cause any
functional difference.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Currently reset methods are not specified directly in the
ata_port_operations table. If a LLD wants to use custom reset
methods, it should construct and use a error_handler which uses those
reset methods. It's done this way for two reasons.
First, the ops table already contained too many methods and adding
four more of them would noticeably increase the amount of necessary
boilerplate code all over low level drivers.
Second, as ->error_handler uses those reset methods, it can get
confusing. ie. By overriding ->error_handler, those reset ops can be
made useless making layering a bit hazy.
Now that ops table uses inheritance, the first problem doesn't exist
anymore. The second isn't completely solved but is relieved by
providing default values - most drivers can just override what it has
implemented and don't have to concern itself about higher level
callbacks. In fact, there currently is no driver which actually
modifies error handling behavior. Drivers which override
->error_handler just wraps the standard error handler only to prepare
the controller for EH. I don't think making ops layering strict has
any noticeable benefit.
This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and
their PMP counterparts propoer ops. Default ops are provided in the
base ops tables and drivers are converted to override individual reset
methods instead of creating custom error_handler.
* ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs
aren't accessible. sata_promise doesn't need to use separate
error_handlers for PATA and SATA anymore.
* softreset is broken for sata_inic162x and sata_sx4. As libata now
always prefers hardreset, this doesn't really matter but the ops are
forced to NULL using ATA_OP_NULL for documentation purpose.
* pata_hpt374 needs to use different prereset for the first and second
PCI functions. This used to be done by branching from
hpt374_error_handler(). The proper way to do this is to use
separate ops and port_info tables for each function. Converted.
Signed-off-by: Tejun Heo <htejun@gmail.com>
libata core layer doesn't care about sht or ->irq_handler. Those are
only of interest to the LLD during initialization. This is confusing
and has caused several drivers to have duplicate unused initializers
for these fields.
Currently only sata_nv uses these fields. Make sata_nv use
->private_data, which is supposed to carry LLD-specific information,
instead and kill ->sht and ->irq_handler. nv_pi_priv structure is
defined and struct literals are used to initialize private_data.
Notational overhead is negligible.
Signed-off-by: Tejun Heo <htejun@gmail.com>
port_info->private_data is currently used for two purposes - to record
private data about the port_info or to specify host->private_data to
use when allocating ata_host.
This overloading is confusing and counter-intuitive in that
port_info->private_data becomes host->private_data instead of
port->private_data. In addition, port_info and host don't correspond
to each other 1-to-1. Currently, the first non-NULL
port_info->private_data is used.
This patch makes port_info->private_data just be what it is -
private_data for the port_info where LLD can jot down extra info.
libata no longer sets host->private_data to the first non-NULL
port_info->private_data, @host_priv argument is added to
ata_pci_init_one() instead. LLDs which use ata_pci_init_one() can use
this argument to pass in pointer to host private data. LLDs which
don't should use init-register model anyway and can initialize
host->private_data directly.
Adding @host_priv instead of using init-register model for LLDs which
use ata_pci_init_one() is suggested by Alan Cox.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
ata_pci_init_one() is the only function which uses ops->irq_handler
and pi->sht. Other initialization functions take the same information
as arguments. This causes confusion and duplicate unused entries in
structures.
Make ata_pci_init_one() take sht as an argument and use ata_interrupt
implicitly. All current users use ata_interrupt and if different irq
handler is necessary open coding ata_pci_init_one() using
ata_prepare_sff_host() and ata_activate_sff_host can be done under ten
lines including error handling and driver which requires custom
interrupt handler is likely to require custom initialization anyway.
As ata_pci_init_one() was the last user of ops->irq_handler, this
patch also kills the field.
Signed-off-by: Tejun Heo <htejun@gmail.com>
libata lets low level drivers build ata_port_operations table and
register it with libata core layer. This allows low level drivers
high level of flexibility but also burdens them with lots of
boilerplate entries.
This becomes worse for drivers which support related similar
controllers which differ slightly. They share most of the operations
except for a few. However, the driver still needs to list all
operations for each variant. This results in large number of
duplicate entries, which is not only inefficient but also error-prone
as it becomes very difficult to tell what the actual differences are.
This duplicate boilerplates all over the low level drivers also make
updating the core layer exteremely difficult and error-prone. When
compounded with multi-branched development model, it ends up
accumulating inconsistencies over time. Some of those inconsistencies
cause immediate problems and fixed. Others just remain there dormant
making maintenance increasingly difficult.
To rectify the problem, this patch implements ata_port_operations
inheritance. To allow LLDs to easily re-use their own ops tables
overriding only specific methods, this patch implements poor man's
class inheritance. An ops table has ->inherits field which can be set
to any ops table as long as it doesn't create a loop. When the host
is started, the inheritance chain is followed and any operation which
isn't specified is taken from the nearest ancestor which has it
specified. This operation is called finalization and done only once
per an ops table and the LLD doesn't have to do anything special about
it other than making the ops table non-const such that libata can
update it.
libata provides four base ops tables lower drivers can inherit from -
base, sata, pmp, sff and bmdma. To avoid overriding these ops
accidentaly, these ops are declared const and LLDs should always
inherit these instead of using them directly.
After finalization, all the ops table are identical before and after
the patch except for setting .irq_handler to ata_interrupt in drivers
which didn't use to. The .irq_handler doesn't have any actual effect
and the field will soon be removed by later patch.
* sata_sx4 is still using old style EH and currently doesn't take
advantage of ops inheritance.
Signed-off-by: Tejun Heo <htejun@gmail.com>
libata lets low level drivers build scsi_host_template and register it
to the SCSI layer. This allows low level drivers high level of
flexibility but also burdens them with lots of boilerplate entries.
This patch implements SHT initializers which can be used to initialize
all the boilerplate entries in a sht. Three variants of them are
implemented - BASE, BMDMA and NCQ - for different types of drivers.
Note that entries can be overriden by putting individual initializers
after the helper macro.
All sht tables are identical before and after this patch.
Signed-off-by: Tejun Heo <htejun@gmail.com>
->irq_clear() is used to clear IRQ bit of a SFF controller and isn't
useful for drivers which don't use libata SFF HSM implementation.
However, it's a required callback and many drivers implement their own
noop version as placeholder. This patch implements ata_noop_irq_clear
and use it to replace those custom placeholders.
Also, SFF drivers which don't support BMDMA don't need to use
ata_bmdma_irq_clear(). It becomes noop if BMDMA address isn't
initialized. Convert them to use ata_noop_irq_clear().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Over the time, ops in ata_port_operations has become a bit confusing.
Reorganize. SFF/BMDMA ops are separated into separate a group as they
will be taken out of ata_port_operations later.
Signed-off-by: Tejun Heo <htejun@gmail.com>
ata_ehi_schedule_probe() was created to hide details of link-resuming
reset magic. Now that all the softreset workarounds are gone,
scheduling probe is very simple - set probe_mask and request RESET.
Kill ata_ehi_schedule_probe() and open code it. This also increases
consistency as ata_ehi_schedule_probe() couldn't cover individual
device probings so they were open-coded even when the helper existed.
While at it, define ATA_ALL_DEVICES as mask of all possible devices on
a link and always use it when requesting probe on link level for
simplicity and consistency. Setting extra bits in the probe_mask
doesn't hurt anybody.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Some controllers can't reliably record the initial D2H FIS after SATA
link is brought online for whatever reason. Advanced controllers
which don't have traditional TF register based interface often have
this problem as they don't really have the TF registers to update
while the controller and link are being initialized.
SKIP_D2H_BSY works around the problem by skipping the wait for device
readiness before issuing SRST, so for such controllers libata issues
SRST blindly and hopes for the best.
Now that libata defaults to hardreset, this workaround is no longer
necessary. For controllers which have support for hardreset, SRST is
never issued by itself. It is only issued as follow-up SRST for
device classification and PMP initialization, so there's no need to
wait for it from prereset.
Kill ATA_LFLAG_SKIP_D2H_BSY.
Signed-off-by: Tejun Heo <htejun@gmail.com>
ATA_EHI_RESUME_LINK has two functions - promote reset to hardreset if
ATA_LFLAG_HRST_TO_RESUME is set and preventing EH from shortcutting
reset action when probing is requested. The former is gone now and
the latter can easily be achieved by making EH to perform at least one
reset if reset is requested, which also makes more sense than
depending on RESUME_LINK flag.
As ATA_EHI_RESUME_LINK was the only EHI reset modifier, this also
kills reset modifier handling.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Now that hardreset is the preferred method of resetting, there's no
need for ATA_LFLAG_HRST_TO_RESUME flag. Kill it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
When both soft and hard resets are available, libata preferred
softreset till now. The logic behind it was to be softer to devices;
however, this doesn't really help much. Rationales for the change:
* BIOS may freeze lock certain things during boot and softreset can't
unlock those. This by itself is okay but during operation PHY event
or other error conditions can trigger hardreset and the device may
end up with different configuration.
For example, after a hardreset, previously unlockable HPA can be
unlocked resulting in different device size and thus revalidation
failure. Similar condition can occur during or after resume.
* Certain ATAPI devices require hardreset to recover after certain
error conditions. On PATA, this is done by issuing the DEVICE RESET
command. On SATA, COMRESET has equivalent effect. The problem is
that DEVICE RESET needs its own execution protocol.
For SFF controllers with bare TF access, it can be easily
implemented but more advanced controllers (e.g. ahci and sata_sil24)
require specialized implementations. Simply using hardreset solves
the problem nicely.
* COMRESET initialization sequence is the norm in SATA land and many
SATA devices don't work properly if only SRST is used. For example,
some PMPs behave this way and libata works around by always issuing
hardreset if the host supports PMP.
Like the above example, libata has developed a number of mechanisms
aiming to promote softreset to hardreset if softreset is not going
to work. This approach is time consuming and error prone.
Also, note that, dependingon how you read the specs, it could be
argued that PMP fan-out ports require COMRESET to start operation.
In fact, all the PMPs on the market except one don't work properly
if COMRESET is not issued to fan-out ports after PMP reset.
* COMRESET is an integral part of SATA connection and any working
device should be able to handle COMRESET properly. After all, it's
the way to signal hardreset during reboot. This is the most used
and recommended (at least by the ahci spec) method of resetting
devices.
So, this patch makes libata prefer hardreset over softreset by making
the following changes.
* Rename ATA_EH_RESET_MASK to ATA_EH_RESET and use it whereever
ATA_EH_{SOFT|HARD}RESET used to be used. ATA_EH_{SOFT|HARD}RESET is
now only used to tell prereset whether soft or hard reset will be
issued.
* Strip out now unneeded promote-to-hardreset logics from
ata_eh_reset(), ata_std_prereset(), sata_pmp_std_prereset() and
other places.
Signed-off-by: Tejun Heo <htejun@gmail.com>
We were already doing what amounts to a get_phy_id from within
get_phy_device, and rather than duplicate this for the TBIPA
probing, we might as well just factor it out and make it available
instead.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
In order to not trip the clocksource watchdog, kgdb must touch the
clocksource watchdog on the return to normal system run state.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
polled console handling support, to access a console in an irq-less
way while in debug or irq context.
absolutely zero impact as long as CONFIG_CONSOLE_POLL is disabled.
(which is the default)
[ jan.kiszka@siemens.com: lots of cleanups ]
[ mingo@elte.hu: redesign, splitups, cleanups. ]
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
kgdb core code. Handles the protocol and the arch details.
[ mingo@elte.hu: heavily modified, simplified and cleaned up. ]
[ xemul@openvz.org: use find_task_by_pid_ns ]
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
add probe_kernel_read() and probe_kernel_write().
Uninlined and restricted to kernel range memory only, as suggested
by Linus.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Move documentation from semaphore.h to semaphore.c as requested by
Andrew Morton. Also reformat to kernel-doc style and add some more
notes about the implementation.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
By removing the negative values of 'count' and relying on the wait_list to
indicate whether we have any waiters, we can simplify the implementation
by removing the protection against an unlikely race condition. Thanks to
David Howells for his suggestions.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
ACPI currently emulates a timeout for semaphores with calls to
down_trylock and sleep. This produces horrible behaviour in terms of
fairness and excessive wakeups. Now that we have a unified semaphore
implementation, adding a real down_trylock is almost trivial.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility. Thanks to Peter Zijlstra for fixing the lockdep
warning. Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
quota.h currently relies on asm/semaphore.h (through some chain; it
doesn't actually include semaphore.h itself) to include wait.h. As
well as being bad practice to rely on an implicit include, subsequent
patches will break this. While I'm in this file, add atomic.h and
list.h, and sort the list of includes.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
double_spin_lock() has no callers, and it can't be used without additional
lockdep annotations, remove it.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In order to avoid the false positive from lockdep, each per-cpu base->lock has
the separate lock class and migrate_hrtimers() uses double_spin_lock().
This is overcomplicated: except for migrate_hrtimers() we never take 2 locks
at once, and migrate_hrtimers() can use spin_lock_nested().
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The back and forth typecasting of restart_block->args is horrible. We
added a separate union member for futex already. Do the same for
nanosleep.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Generic code is not supposed to include irq.h. Replace this include
> by linux/hardirq.h instead and add/replace an include of linux/irq.h
> in asm header files where necessary.
> This change should only matter for architectures that make use of
> GENERIC_CLOCKEVENTS.
> Architectures in question are mips, x86, arm, sh, powerpc, uml and sparc64.
>
> I did some cross compile tests for mips, x86_64, arm, powerpc and sparc64.
> This patch fixes also build breakages caused by the include replacement in
> tick-common.h.
I generally dislike adding optional linux/* includes in asm/* includes -
I'm nervous about this causing include loops.
However, there's a separate point to be discussed here.
That is, what interfaces are expected of every architecture in the kernel.
If generic code wants to be able to set the affinity of interrupts, then
that needs to become part of the interfaces listed in linux/interrupt.h
rather than linux/irq.h.
So what I suggest is this approach instead (against Linus' tree of a
couple of days ago) - we move irq_set_affinity() and irq_can_set_affinity()
to linux/interrupt.h, change the linux/irq.h includes to linux/interrupt.h
and include asm/irq_regs.h where needed (asm/irq_regs.h is supposed to be
rarely used include since not much touches the stacked parent context
registers.)
Build tested on ARM PXA family kernels and ARM's Realview platform
kernels which both use genirq.
[ tglx@linutronix.de: add GENERIC_HARDIRQ dependencies ]
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
ConnectX devices support checksum generation and verification of TCP
and UDP packets for UD IPoIB messages. This patch checks if the HCA
supports this and sets the IB_DEVICE_UD_IP_CSUM capability flag if it
does. It implements support for handling the IB_SEND_IP_CSUM send
flag and setting the csum_ok field in receive work completions.
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Ali Ayub <ali@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The struct mlx4_interface.event() method was supposed to get an enum
mlx4_dev_event, but the driver code was actually passing in the
hardware enum mlx4_event values. Fix up the callers of
mlx4_dispatch_event() so that they pass in the right type of value,
and fix up the event method in mlx4_ib so that it can handle the enum
mlx4_dev_event values.
This eliminates the need for the subtype parameter to the event
method, so remove it.
This also fixes the sparse warning
drivers/net/mlx4/intf.c:127:48: warning: mixing different enum types
drivers/net/mlx4/intf.c:127:48: int enum mlx4_event versus
drivers/net/mlx4/intf.c:127:48: int enum mlx4_dev_event
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Multi-line comments weren't all CodingStyle compliant
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Having the id field be an int was making more complex bus topologies
excessively difficult. For now, just convert it to a string, and
change all instances of "bus->id = val" to
snprintf(id, MII_BUS_ID_LEN, "%x", val).
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
[TCP]: Add return value indication to tcp_prune_ofo_queue().
PS3: gelic: fix the oops on the broken IE returned from the hypervisor
b43legacy: fix DMA mapping leakage
mac80211: remove message on receiving unexpected unencrypted frames
Update rt2x00 MAINTAINERS entry
Add rfkill to MAINTAINERS file
rfkill: Fix device type check when toggling states
b43legacy: Fix usage of struct device used for DMAing
ssb: Fix usage of struct device used for DMAing
MAINTAINERS: move to generic repository for iwlwifi
b43legacy: fix initvals loading on bcm4303
rtl8187: Add missing priv->vif assignments
netconsole: only set CON_PRINTBUFFER if the user specifies a netconsole
[CAN]: Update documentation of struct sockaddr_can
MAINTAINERS: isdn4linux@listserv.isdn4linux.de is subscribers-only
[TCP]: Fix never pruned tcp out-of-order queue.
[NET_SCHED] sch_api: fix qdisc_tree_decrease_qlen() loop
dev_set_net is called for
- just allocated devices
- devices moving from one namespace to another
release_net has proper check inside to distinguish these cases.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently vlan group is searched using one key - the ifindex.
We'll have to lookup the vlan_group by two keys - ifindex and
net. Turning the vlan_group lookup key to struct net_device
pointer will make this process easier.
Besides, this will eliminate one more place in the networking,
that assumes that indexes are unique in the kernel.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The THERMAL_MAX_TRIPS value is set to 10. It is too few for the Compaq AP550
machine which has 12 trip points.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Len Brown <lenb@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mb_cache_entry_alloc() was allocating cache entries with GFP_KERNEL. But
filesystems are calling this function while holding xattr_sem so possible
recursion into the fs violates locking ordering of xattr_sem and transaction
start / i_mutex for ext2-4. Change mb_cache_entry_alloc() so that filesystems
can specify desired gfp mask and use GFP_NOFS from all of them.
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Dave Jones <davej@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes DMA on architectures where DMA is nontrivial, like PPC64.
We must use the host-device's (PCI) struct device for any DMA
operation instead of the SSB device. For this we add a new
struct device pointer to the SSB device structure that will always
point to the right device for DMAing.
Without this patch b43 and b44 drivers won't work on complex-DMA
architectures, that for example need dev->archdata for DMA operations.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch remove the usage of a nonexisting kconfig variable.
Reported-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Robert P. J. Day spotted that my removal of the Sangoma drivers missed
a few bits.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The per node counters are used mainly for showing data through the sysfs API.
If that API is not compiled in then there is no point in keeping track of this
data. Disable counters for the number of slabs and the number of total slabs
if !SLUB_DEBUG. Incrementing the per node counters is also accessing a
potentially contended cacheline so this could actually be a performance
benefit to embedded systems.
SLABINFO support is also affected. It now must depends on SLUB_DEBUG (which
is on by default).
Patch also avoids a check for a NULL kmem_cache_node pointer in new_slab()
if the system is not compiled with NUMA support.
[penberg@cs.helsinki.fi: fix oops and move ->nr_slabs into CONFIG_SLUB_DEBUG]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (31 commits)
[BRIDGE]: Fix crash in __ip_route_output_key with bridge netfilter
[NETFILTER]: ipt_CLUSTERIP: fix race between clusterip_config_find_get and _entry_put
[IPV6] ADDRCONF: Don't generate temporary address for ip6-ip6 interface.
[IPV6] ADDRCONF: Ensure disabling multicast RS even if privacy extensions are disabled.
[IPV6]: Use appropriate sock tclass setting for routing lookup.
[IPV6]: IPv6 extension header structures need to be packed.
[IPV6]: Fix ipv6 address fetching in raw6_icmp_error().
[NET]: Return more appropriate error from eth_validate_addr().
[ISDN]: Do not validate ISDN net device address prior to interface-up
[NET]: Fix kernel-doc for skb_segment
[SOCK] sk_stamp: should be initialized to ktime_set(-1L, 0)
net: check for underlength tap writes
net: make struct tun_struct private to tun.c
[SCTP]: IPv4 vs IPv6 addresses mess in sctp_inet[6]addr_event.
[SCTP]: Fix compiler warning about const qualifiers
[SCTP]: Fix protocol violation when receiving an error lenght INIT-ACK
[SCTP]: Add check for hmac_algo parameter in sctp_verify_param()
[NET_SCHED] cls_u32: refcounting fix for u32_delete()
[DCCP]: Fix skb->cb conflicts with IP
[AX25]: Potential ax25_uid_assoc-s leaks on module unload.
...
This patch adds the ebtables nflog watcher to the kernel in order to
allow ebtables log through the nfnetlink_log backend.
Signed-off-by: Peter Warasin <peter@endian.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Connection tracking helpers (specifically FTP) need to be called
before NAT sequence numbers adjustments are performed to be able
to compare them against previously seen ones. We've introduced
two new hooks around 2.6.11 to maintain this ordering when NAT
modules were changed to get called from conntrack helpers directly.
The cost of netfilter hooks is quite high and sequence number
adjustments are only rarely needed however. Add a RCU-protected
sequence number adjustment function pointer and call it from
IPv4 conntrack after calling the helper.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Move the UDP-Lite conntrack checksum validation to a generic helper
similar to nf_checksum() and make it fall back to nf_checksum()
in case the full packet is to be checksummed and hardware checksums
are available. This is to be used by DCCP conntrack, which also
needs to verify partial checksums.
Signed-off-by: Patrick McHardy <kaber@trash.net>
The use of xt_sctp.h flagged up -Wshadow warnings in userspace, which
prompted me to look at it and clean it up. Basic operations have been
directly replaced by library calls (memcpy, memset is both available
in the kernel and userspace, and usually faster than a self-made
loop). The is_set and is_clear functions now use a processing time
shortcut, too.
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Commit 9335f047fe aka
"[NETFILTER]: ip_tables: per-netns FILTER, MANGLE, RAW"
added per-netns _view_ of iptables rules. They were shown to user, but
ignored by filtering code. Now that it's possible to at least ping loopback,
per-netns tables can affect filtering decisions.
netns is taken in case of
PRE_ROUTING, LOCAL_IN -- from in device,
POST_ROUTING, LOCAL_OUT -- from out device,
FORWARD -- from in device which should be equal to out device's netns.
This code is relatively new, so BUG_ON was plugged.
Wrappers were added to a) keep code the same from CONFIG_NET_NS=n users
(overwhelming majority), b) consolidate code in one place -- similar
changes will be done in ipv6 and arp netfilter code.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This expresses __skb_queue_tail() in terms of __skb_insert(),
using __skb_insert_before() as auxiliary function.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This expresses __skb_append in terms of __skb_queue_after, exploiting that
__skb_append(old, new, list) = __skb_queue_after(list, old, new).
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
By reordering, __skb_queue_after() is expressed in terms of __skb_insert().
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
By rearranging the order of declarations, __skb_dequeue() is expressed in terms of
* skb_peek() and
* __skb_unlink(),
thus in effect mirroring the analogue implementation of __skb_dequeue_tail().
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
struct ipv6_opt_hdr is the common structure for IPv6 extension
headers, and it is common to increment the pointer to get
the real content. On the other hand, since the structure
consists only of 1-byte next-header field and 1-byte length
field, size of that structure depends on architecture; 2 or 4.
Add "packed" attribute to get 2.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since NETDEV_REGISTER notifier chain is responsible for creating
inet6_dev{}, we do not need to call ipv6_find_idev() directly here.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The xfrm_get_policy() and xfrm_add_pol_expire() put some rather large structs
on the stack to work around the LSM API. This patch attempts to fix that
problem by changing the LSM API to require only the relevant "security"
pointers instead of the entire SPD entry; we do this for all of the
security_xfrm_policy*() functions to keep things consistent.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's no reason for this to be in the header, and it just hurts
recompile time.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Max Krasnyanskiy <maxk@qualcomm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'docs' of git://git.lwn.net/linux-2.6:
Add additional examples in Documentation/spinlocks.txt
Move sched-rt-group.txt to scheduler/
Documentation: move rpc-cache.txt to filesystems/
Documentation: move nfsroot.txt to filesystems/
Spell out behavior of atomic_dec_and_lock() in kerneldoc
Fix a typo in highres.txt
Fixes to the seq_file document
Fill out information on patch tags in SubmittingPatches
Add the seq_file documentation
git commit 54a0151041 ("asmlinkage_protect
replaces prevent_tail_call") causes this build failure on s390:
AS arch/s390/kernel/entry64.o
In file included from arch/s390/kernel/entry64.S:14:
include/linux/linkage.h:34: error: syntax error in macro parameter list
make[1]: *** [arch/s390/kernel/entry64.o] Error 1
make: *** [arch/s390/kernel] Error 2
and some other architectures. The reason is that some architectures add
the "-traditional" flag to the invocation of $(AS), which disables
variadic macro argument support.
So just surround the new define with an #ifndef __ASSEMBLY__ to prevent
any side effects on asm code.
Cc: Roland McGrath <roland@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Increase the PNP "number of devices" limit. We currently use an unsigned
char, which limits us to 256 devices per protocol. This patch changes that to
an unsigned int.
Not all backends can take advantage of this: we limit ISAPNP to 10 devices in
isapnp_cfg_begin(), and PNPBIOS is limited to 256 devices because the BIOS
interfaces use a one-byte device node number.
But there is no limit on the number of PNPACPI devices we may have. Large HP
Integrity machines have more than 256, which causes the current "unsigned char
number" to wrap around. This causes errors like this:
pnp: PnP ACPI init
kobject_add failed for 00:00 with -EEXIST, don't try to register things with the same name in the same directory.
Call Trace:
[<a000000100010720>] show_stack+0x40/0xa0
[<a0000001000107b0>] dump_stack+0x30/0x60
[<a0000001001dbdf0>] kobject_add+0x290/0x2c0
[<a0000001002bfd40>] device_add+0x160/0x860
[<a0000001002c0470>] device_register+0x30/0x60
[<a00000010026ba70>] __pnp_add_device+0x130/0x180
[<a00000010026bb70>] pnp_add_device+0xb0/0xe0
[<a0000001007f2730>] pnpacpi_add_device+0x510/0x5a0
[<a0000001007f2810>] pnpacpi_add_device_handler+0x50/0x80
This patch increases the limit to fix this PNPACPI problem. It should not
have any adverse effect on ISAPNP or PNPBIOS because their limits are still
enforced in the backends.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's really a pretty ugly thing to need, and some day it will hopefully
be obviated by teaching gcc about the magic calling conventions for the
low-level system call code, but in the meantime we can at least add big
honking comments about why we need these insane and strange macros.
I took my comments from my version of the macro, but I ended up deciding
to just pick Roland's version of the actual code instead (with his
prettier syntax that uses vararg macros). Thus the previous two commits
that actually implement it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The prevent_tail_call() macro works around the problem of the compiler
clobbering argument words on the stack, which for asmlinkage functions
is the caller's (user's) struct pt_regs. The tail/sibling-call
optimization is not the only way that the compiler can decide to use
stack argument words as scratch space, which we have to prevent.
Other optimizations can do it too.
Until we have new compiler support to make "asmlinkage" binding on the
compiler's own use of the stack argument frame, we have work around all
the manifestations of this issue that crop up.
More cases seem to be prevented by also keeping the incoming argument
variables live at the end of the function. This makes their original
stack slots attractive places to leave those variables, so the compiler
tends not clobber them for something else. It's still no guarantee, but
it handles some observed cases that prevent_tail_call() did not.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SKF_ADF_NLATTR searches for a netlink attribute, which avoids manually
parsing and walking attributes. It takes the offset at which to start
searching in the 'A' register and the attribute type in the 'X' register
and returns the offset in the 'A' register. When the attribute is not
found it returns zero.
A top-level attribute can be located using a filter like this
(example for nfnetlink, using struct nfgenmsg):
...
{
/* A = offset of first attribute */
.code = BPF_LD | BPF_IMM,
.k = sizeof(struct nlmsghdr) + sizeof(struct nfgenmsg)
},
{
/* X = CTA_PROTOINFO */
.code = BPF_LDX | BPF_IMM,
.k = CTA_PROTOINFO,
},
{
/* A = netlink attribute offset */
.code = BPF_LD | BPF_B | BPF_ABS,
.k = SKF_AD_OFF + SKF_AD_NLATTR
},
{
/* Exit if not found */
.code = BPF_JMP | BPF_JEQ | BPF_K,
.k = 0,
.jt = <error>
},
...
A nested attribute below the CTA_PROTOINFO attribute would then
be parsed like this:
...
{
/* A += sizeof(struct nlattr) */
.code = BPF_ALU | BPF_ADD | BPF_K,
.k = sizeof(struct nlattr),
},
{
/* X = CTA_PROTOINFO_TCP */
.code = BPF_LDX | BPF_IMM,
.k = CTA_PROTOINFO_TCP,
},
{
/* A = netlink attribute offset */
.code = BPF_LD | BPF_B | BPF_ABS,
.k = SKF_AD_OFF + SKF_AD_NLATTR
},
...
The data of an attribute can be loaded into 'A' like this:
...
{
/* X = A (attribute offset) */
.code = BPF_MISC | BPF_TAX,
},
{
/* A = skb->data[X + k] */
.code = BPF_LD | BPF_B | BPF_IND,
.k = sizeof(struct nlattr),
},
...
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sk_filter function is too big to be inlined. This saves 2296 bytes
of text on allyesconfig.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some minor style cleanups:
* Move __KERNEL__ definitions to one place in filter.h
* Use const for sk_filter_len
* Line wrapping
* Put EXPORT_SYMBOL next to function definition
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds support for block based I/O to SSB.
This is needed in order to efficiently support PIO data
transfers to the card.
The block-I/O support is only compiled, if it's selected by the
weird driver that needs it. So there's no overhead for sane devices.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Turn the SSB bus suspend mechanism upside down.
Instead of deciding by an internal reference count when to suspend/resume,
let the parent bus call us in their suspend/resume routine.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The 'disable_cb' callback is designed as an optimization to tell the host
we don't need callbacks now. As it is not reliable, the debug check is
overzealous: it can happen on two CPUs at the same time. Document this.
Even if it were reliable, the virtio_net driver doesn't disable
callbacks on transmit so the START_USE/END_USE debugging reentrance
protection can be easily tripped even on UP.
Thanks to Balaji Rao for the bug report and testing.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
CC: Balaji Rao <balajirrao@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Every current transport class calls transport_container_release but
ignores the return value. This is catastrophic if it returns an error
because the containers are part of a global list and the next action of
almost every transport class is to free the memory used by the
container.
Fix this by making transport_container_release a void, but making it BUG
if attribute_container_release returns an error ... this catches the
root cause of a system panic much earlier. If we don't do this, we get
an eventual BUG when the attribute container list notices the corruption
caused by the freed memory it's still referencing.
Also made attribute_container_release __must_check as a reminder.
Cc: Greg KH <greg@kroah.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This patch adds new three helper functions to copy data between an SG
list and a linear buffer.
- sg_copy_from_buffer copies data from linear buffer to an SG list
- sg_copy_to_buffer copies data from an SG list to a linear buffer
When the APIs copy data from a linear buffer to an SG list,
flush_kernel_dcache_page is called. It's not necessary for everyone
but it's a no-op on most architectures and in general the API is not
used in performance critical path.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tejun Heo