Freezing is performed atomic w.r.t. host_set->lock and once frozen
LLDD is not allowed to access the port or any qc on it. Also, libata
makes sure that no new qc gets issued to a frozen port.
A frozen port is thawed after a reset operation completes
successfully, so reset methods must do its job while the port is
frozen. During initialization all ports get frozen before requesting
IRQ, so reset methods are always invoked on a frozen port.
Optional ->freeze and ->thaw operations notify LLDD that the port is
being frozen and thawed, respectively. LLDD can disable/enable
hardware interrupt in these callbacks if the controller's IRQ mask can
be changed dynamically. If the controller doesn't allow such
operation, LLDD can check for frozen state in the interrupt handler
and ack/clear interrupts unconditionally while frozen.
Signed-off-by: Tejun Heo <htejun@gmail.com>
ata_port_schedule_eh() directly schedules EH for @ap without
associated qc. Once EH scheduled, no further qc is allowed and EH
kicks in as soon as all currently active qc's are drained.
ata_port_abort() schedules all currently active commands for EH by
qc_completing them with ATA_QCFLAG_FAILED set. If ata_port_abort()
doesn't find any qc to abort, it directly schedule EH using
ata_port_schedule_eh().
These two functions provide ways to invoke EH for conditions which
aren't directly related to any specfic qc.
Signed-off-by: Tejun Heo <htejun@gmail.com>
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 ATA_FLAG_EH_{PENDING|FROZEN}, ATA_ATA_QCFLAG_{FAILED|SENSE_VALID}
and ops->freeze, thaw, error_handler, post_internal_cmd() for new EH.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Implement ata_{port|dev}_printk() which prefixes the message with
proper identification string. This change is necessary for later PM
support because devices and links should be identified differently
depending on how they are attached.
This also helps unifying device id strings. Currently, there are two
forms in use (P is the port number D device number) - 'ataP(D):', and
'ataP: dev D '. These macros also make it harder to forget proper ID
string (e.g. printing only port number when a device is in question).
Debug message handling can be integrated into these printk macros by
passing debug type and level via @lv.
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>
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>
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>
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>
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>
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>
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>
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>
Add a new qc flag ATA_QCFLAG_IO. This flag gets set for normal IO
commands originating from SCSI midlayer. This information will be
used by EH to determine transfer speed reconfiguration.
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>
* Reorder ATA_DFLAG_* such that feature flags determined by
ata_dev_configure() are on lower bits. Reserve lower eight bits
for this purpose and allocate dynamic flags from bit 8.
* Reorder ATA_FLAG_* such that feature flags determined during driver
initiailization are on bits 0:15, dynamic flags on 16:23 and LLDD
specific flags on 24:31.
* Kill trailing white space and lower-case an one line comment for
consistency.
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>
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>
For the time being we cannot use ata_dev_present() as it was renamed
to ata_dev_enabled() but we still need presence test. Implement
negation of the test. Conveniently, the negated result is needed in
more places. This is suggested by Jeff Garzik.
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>
Add a field to the host_set called 'flags' (was host_set_flags changed
to suit Jeff)
Add a simplex_claimed field so we can remember who owns the DMA channel
Add a ->mode_filter() hook to allow drivers to filter modes
Add docs for mode_filter and set_mode
Filter according to simplex state
Filter cable in core
This provides the needed framework to support all the mode rules found
in the PATA world. The simplex filter deals with 'to spec' simplex DMA
systems found in older chips. The cable filter avoids duplicating the
same rules in each chip driver with PATA. Finally the mode filter is
neccessary because drive/chip combinations have errata that forbid
certain modes with some drives or types of ATA object.
Drive speed setup remains per channel for now and the filters now use
the framework Tejun put into place which cleans them up a lot from the
older libata-pata patches.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some hardware doesn't want the usual mode setup logic running. This
allows the hardware driver to replace it for special cases in the least
invasive way possible.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This is the minimal patch set to enable the current code to be used with
a controller following SFF (ie any PATA and early SATA controllers)
safely without crashes if there is no BMDMA area or if BMDMA is not
assigned by the BIOS for some reason.
Simplex status is recorded but not acted upon in this change, this isn't
a problem with the current drivers as none of them are for simplex
hardware. A following diff will deal with that.
The flags in the probe structure remain ->host_set_flags although Jeff
asked me to rename them, simply because the rename would break the usual
Linux rules that old code should break when there are changes. not
compile and run and then blow up/eat your computer/etc. Renaming this
later is a trivial exercise once a better name is chosen.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
E.D.D. has no user in-tree and mostly useless. Kill it. For possible
out-of-tree users, add a nice warning message and error handling if
LLDD doesn't report any useable reset mechanism (and thus tries to use
E.D.D.).
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Remove some of the dependence on the host_set struct
in preparation for supporting SAS HBAs. Adds a struct device
pointer to the ata_port struct.
Signed-off-by: Brian King <brking@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
At the moment libata doesn't pass pm_message_t down ata_device_suspend.
This causes drives to be powered down when we just want a freeze,
causing unnecessary wear and tear. This patch gets pm_message_t passed
down so that it can be used to determine whether to power down the
drive.
Signed-off-by: Nigel Cunningham <nigel@suspend2.net>
drivers/scsi/libata-core.c | 5 +++--
drivers/scsi/libata-scsi.c | 4 ++--
drivers/scsi/scsi_sysfs.c | 2 +-
include/linux/libata.h | 4 ++--
include/scsi/scsi_host.h | 2 +-
5 files changed, 9 insertions(+), 8 deletions(-)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add per-dev pio/mwdma/udma_mask. All transfer mode limits used to be
applied to ap->*_mask which unnecessarily restricted other devices
sharing the port. This change will also benefit later EH speed down
and hotplug.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add some dummy noop functions for use by libata clients
that do not need to do anything. Future SAS patches will
utilize these functions.
Signed-off-by: Brian King <brking@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
SCSI midlayer has moved hostt->eh_timed_out to transport template. As
libata doesn't need full-blown transport support yet, implement
minimal transport for libata. No transport class or whatsoever, just
empty transport template with ->eh_timed_out hook.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Add ATA_BITS_*, ATA_MASK_* macros and reorder xfer_mask fields such
that higher transfer mode is placed at higher order bit. As thie
reordering breaks ata_mode_string(), this patch also rewrites
ata_mode_string().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement port_task. LLDD's can schedule a function to be executed
with context after specified delay. libata core takes care of
synchronization against EH. This is generalized form of pio_task and
packet_task which are tied to PIO hsm implementation.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_dev_revalidate() re-reads IDENTIFY PAGE of the given device and
makes sure it's the same device as the configured one. Once it's
verified that it's the same device, @dev is configured according to
newly read IDENTIFY PAGE. Note that revalidation currently doesn't
invoke transfer mode reconfiguration.
Criteria for 'same device'
* same class (of course)
* same model string
* same serial string
* if ATA, same n_sectors (to catch geometry parameter changes)
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
