There are several ways a qc can get schedule for EH in new EH. This
patch implements one of them - completing a qc with ATA_QCFLAG_FAILED
set or with non-zero qc->err_mask. ALL such qc's are examined by EH.
New EH schedules a qc for EH from completion iff ->error_handler is
implemented, qc is marked as failed or qc->err_mask is non-zero and
the command is not an internal command (internal cmd is handled via
->post_internal_cmd). The EH scheduling itself is performed by asking
SCSI midlayer to schedule EH for the specified scmd.
For drivers implementing old-EH, nothing changes. As this change
makes ata_qc_complete() rather large, it's not inlined anymore and
__ata_qc_complete() is exported to other parts of libata for later
use.
Signed-off-by: Tejun Heo <htejun@gmail.com>
New EH framework has clear distinction about who owns a qc. Every qc
starts owned by normal execution path - PIO, interrupt or whatever.
When an exception condition occurs which affects the qc, the qc gets
scheduled for EH. Note that some events (say, link lost and regained,
command timeout) may schedule qc's which are not directly related but
could have been affected for EH too. Scheduling for EH is atomic
w.r.t. ap->host_set->lock and once schedule for EH, normal execution
path is not allowed to access the qc in whatever way. (PIO
synchronization acts a bit different and will be dealt with later)
This patch make ata_qc_from_tag() check whether a qc is active and
owned by normal path before returning it. If conditions don't match,
NULL is returned and thus access to the qc is denied.
__ata_qc_from_tag() is the original ata_qc_from_tag() and is used by
libata core/EH layers to access inactive/failed qc's.
This change is applied only if the associated LLDD implements new EH
as indicated by non-NULL ->error_handler
Signed-off-by: Tejun Heo <htejun@gmail.com>
New EH may issue internal commands to recover from error while failed
qc's are still hanging around. To allow such usage, reserve tag
ATA_MAX_QUEUE-1 for internal command. This also makes it easy to tell
whether a qc is for internal command or not. ata_tag_internal() test
implements this test.
To avoid breaking existing drivers, ata_exec_internal() uses
ATA_TAG_INTERNAL only for drivers which implement ->error_handler.
For drivers using old EH, tag 0 is used. Note that this makes
ata_tag_internal() test valid only when ->error_handler is
implemented. This is okay as drivers on old EH should not and does
not have any reason to use ata_tag_internal().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Add dev->ap which points back to the port the device belongs to. This
makes it unnecessary to pass @ap for silly reasons (e.g. printks).
Also, this change is necessary to accomodate later PM support which
will introduce ATA link inbetween port and device.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Use new SCR and on/offline functions. Note that for LLDD which know
it implements SCR callbacks, SCR functions are guaranteed to succeed
and ata_port_online() == !ata_port_offline().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Implement ata_scr_{valid|read|write|write_flush}() and
ata_port_{online|offline}(). These functions replace
scr_{read|write}() and sata_dev_present().
Major difference between between the new SCR functions and the old
ones is that the new ones have a way to signal error to the caller.
This makes handling SCR-available and SCR-unavailable cases in the
same path easier. Also, it eases later PM implementation where SCR
access can fail due to various reasons.
ata_port_{online|offline}() functions return 1 only when they are
affirmitive of the condition. e.g. if SCR is unaccessible or
presence cannot be determined for other reasons, these functions
return 0. So, ata_port_online() != !ata_port_offline(). This
distinction is useful in many exception handling cases.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Init ap->cbl to ATA_CBL_SATA in ata_host_init(). This is necessary
for soon-to-follow SCR handling function changes. LLDDs are free to
change ap->cbl during probing.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Add qc->result_tf and ATA_QCFLAG_RESULT_TF. This moves the
responsibility of loading result TF from post-compltion path to qc
execution path. qc->result_tf is loaded if explicitly requested or
the qc failsa. This allows more efficient completion implementation
and correct handling of result TF for controllers which don't have
global TF representation such as sil3124/32.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Make ata_do_reset() deal only with reset. postreset is now the
responsibility of the caller. This is simpler and eases later
prereset addition.
Signed-off-by: Tejun Heo <htejun@gmail.com>
It's not a very good idea to allocate memory during EH. Use
statically allocated buffer for dev->id[] and add 512byte buffer
ap->sector_buf. This buffer is owned by EH (or probing) and to be
used as temporary buffer for various purposes (IDENTIFY, NCQ log page
10h, PM GSCR block).
Signed-off-by: Tejun Heo <htejun@gmail.com>
ap->active_tag was cleared in ata_qc_free(). This left ap->active_tag
dangling after ata_qc_complete(). Spurious interrupts inbetween could
incorrectly access the qc. Clear active_tag in ata_qc_complete().
This change is necessary for later EH changes.
Signed-off-by: Tejun Heo <htejun@gmail.com>
ata_bus_probe() doesn't clear dev->class after ->phy_reset(). This
can result in falsely enabled devices if probing fails. Clear
dev->class to ATA_DEV_UNKNOWN after fetching it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
While moving ata_scsi_error() from LLDD sht to libata transportt,
EXPORT_SYMBOL_GPL() entry was left out. Kill it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Rename ata_down_sata_spd_limit() and friends to sata_down_spd_limit()
and likewise for simplicity & consistency.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Move ata_set_mode() failure handling outside of ap->ops->set_mode if
clause such that it can handle ap->ops->set_mode failures after it's
updated.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Devices which consumed all their changes used to be disabled every
iteration. This causes unnecessary noise in the console output.
Disable once and leave alone.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
As waiting for some register bits to change seems to be a common
operation shared by some controllers, implement helper function
ata_wait_register(). This function also takes care of register write
flushing.
Note that the condition is inverted, the wait is over when the masked
value does NOT match @val. As we're waiting for bits to change, this
test is more powerful and allows the function to be used in more
places.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
@verbose was added to ata_reset_fn_t because AHCI complained during
probing if no device was attached to the port. However, muting
failure message isn't the correct approach. Reset methods are
responsible for detecting no device condition and finishing
successfully. Now that AHCI softreset is fixed, kill @verbose.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make setting CBL type responsibility of probeinit. This allows using
only ap->cbl == ATA_CBL_SATA test in all other parts. Without this,
ata_down_sata_spd_limit() doesn't work during probe reset.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Overriding the whole EH code is a per-transport, not per-host thing.
Move ->eh_strategy_handler to the transport class, same as
->eh_timed_out.
Downside is that scsi_host_alloc can't check for the total lack of EH
anymore, but the transition period from old EH where we needed it is
long gone already.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Convert the ATAPI_ENABLE_DMADIR compile time option needed
by some SATA-PATA bridge to runtime module parameter.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make libata-core routines which will be used by EH implementation
extern.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
A lot of EH codes are about to be added to libata. Separate out
libata-eh.c. ata_scsi_timed_out(), ata_scsi_error(),
ata_qc_timeout(), ata_eng_timeout(), ata_eh_qc_complete() and
ata_eh_qc_retry() are moved. No code is changed by this patch.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The current code passes pointer to ap around and repeatedly performs
ata_qc_from_tag() to access the ongoing qc. This is unnatural and
makes EH synchronization cumbersome. Make PIO codes deal with qc
instead of ap.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_dev_set_mode() is now responsible for managing ATA_DFLAG_PIO.
Clear it before setting it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_dev_configure() should not clear dynamic device flags determined
elsewhere. Lower eight bits are reserved for feature flags, define
ATA_DFLAG_CFG_MASK and clear only those bits before configuring
device. Without this patch, ATA_DFLAG_PIO gets turned off during
revalidation making PIO mode unuseable.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Rename ATA_FLAG_PORT_DISABLED to ATA_FLAG_DISABLED for consistency.
(ATA_FLAG_* are always about ports).
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make sure ata_dev_revalidate() complains on failures and kill
revalidation failure message printed from ata_dev_set_mode().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_bus_probe() now marks failed devices properly and leaves
meaningful transfer mode masks. This patch makes ata_dev_xfermask()
consider disable devices when determining PIO mode to avoid violating
device selection timing.
While at it, move port-wide resttriction out of device iteration loop
and try to make the function look a bit prettier.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Improve ata_bus_probe() such that configuration failures are handled
better. Each device is given ATA_PROBE_MAX_TRIES chances, but any
non-transient error (revalidation failure with -ENODEV, configuration
failure with -EINVAL...) disables the device directly. Any IO error
results in SATA PHY speed down and ata_set_mode() failure lowers
transfer mode. The last try always puts a device into PIO-0.
After each failure, the whole port is reset to make sure that the
controller and all the devices are in a known and stable state. The
reset also applies SATA SPD configuration if necessary.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement ata_down_xfermask_limit(). This function manipulates
@dev->pio/mwdma/udma_mask such that the next lower transfer mode is
selected. This will be used to improve ata_bus_probe() failure
handling and later by EH.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some devices react badly if resets are performed back-to-back. Give
devices some time to breath and tell user that we're taking a nap.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make ata_drive_probe_reset() use SATA SPD configuration. Hardreset
will be force if speed renegotiation is necessary. Also, if a
hardreset fails, PHY speed is stepped down and hardreset is retried
until the lowest speed is reached.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ap->sata_spd_limit contrains SATA PHY speed of the port. It is
initialized to the configured value prior to probing thus preserving
BIOS configured value. hardreset is responsible for applying SPD
limit and sata_std_hardreset() is updated to do that. SATA SPD limit
will be used to enhance failure handling during probing and later by
EH.
This patch also normalizes some comments around affected code.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Don't overwrite SPD setting during hard reset. This change has the
(intended) side effect of honoring the BIOS configuration.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
When ata_set_mode() fails on a device, make ata_set_mode() return
error code and pointer to the device instead of disabling it directly.
This gives more control to higher level driving logic.
This patch does not change the end result (configured transfer mode)
although it may make libata repeat mode configuration to the peer of a
failing device. Later ata_bus_probe() rewrite will make full use of
this change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Merge ata_host_set_pio() and ata_host_set_dma() into ata_set_mode()
and use function-level *dev to iterate over devices. This eases
soon-to-follow ata_set_mode() interface change.
While at it, kill an unnecessary comment and normalize others.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make ata_set_mode() return without doing anything if there is no
device on the port. This is in preparation for ata_bus_probe()
changes.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch renames ata_dev_present() to ata_dev_enabled() and adds
ata_dev_disabled(). This is to discern the state where a device is
present but disabled from not-present state. This disctinction is
necessary when configuring transfer mode because device selection
timing must not be violated even if a device fails to configure.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Tejun Heo