None of the drives I have follows what the standard says about
transfer chunk size. Of the four SATA and six PATA ATAPI devices
tested, four ignore transfer chunk size completely and the ones which
honor it don't behave according to the spec when it's odd.
According to the spec, transfer chunk size can be odd if the amount of
data to transfer equals or is smaller than the chunk size and the
device can indicate the same odd number and transfer the whole thing
at one go with a pad byte appended. However, in reality, none of the
drives I have does that. They all indicate and transfer even number
of bytes one byte shorter than the chunk size first; then indicate and
transfer two bytes, which is clearly out of spec.
In addition to unnecessary second PIO data phase, this also creates a
weird problem when combined with SATA controllers which perform PIO
via DMA. Some of these controllers use actualy number of bytes
received to update DMA pointer so chunks which are sized 4n + 2 makes
DMA pointer off by two bytes. This causes data corruption and buffer
overruns.
This patch rounds nbytes up to the nearest even number such that ATAPI
devices don't split data transfer for the last odd byte. This
shouldn't confuse controllers which depend on transfer chunk size as
devices will report the rounded-up number, actually transfer that much
and padding buffer is there to receive them.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Sebastian Kemper reported that issuing CD/DVD commands under libata is
not fully compatible with ide-scsi. In particular, the
GPCMD_SET_STREAMING was being rejected at the host level in some
instances.
The reason is that libata-scsi insists upon the cmd_len field exactly
matching the SCSI opcode being issued, whereas ide-scsi tolerates
12-byte commands contained within a 16-byte (cmd_len) CDB.
There doesn't seem to be a good reason for us to not be compatible
there, so here is a patch to fix libata-scsi to permit SCSI opcodes so
long as they fit within whatever size CDB is provided.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Implement ATA_QCFLAG_QUIET which indicates that there's no need to
report if the command fails with AC_ERR_DEV and set it for passthrough
commands.
Combined with previous changes, this now makes device errors for all
direct commands reported directly to the issuer without going through
EH actions and reporting.
Note that EH is still invoked after non-IO device errors to determine
the nature of the error and resume command execution (some controller
requires special care after error to continue). It just performs
default maintenance after error, examines what's going on, realizes
that it's none of its business and reports the command failure without
logging any error messages.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ATA_QCFLAG_IO is used to mark commands which are used to perform
regluar IO transfers via block layer. These commands are assumed to
be valid and taken more seriously during error handling. Cache flush
is used by regular IO path and necessary for data integrity. Mark it
with ATA_QCFLAG_IO.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Device Initiated Power Management, which is defined
in SATA 2.5 can be enabled for disks which support it.
This patch enables DIPM when the user sets the link
power management policy to "min_power".
Additionally, libata drivers can define a function
(enable_pm) that will perform hardware specific actions to
enable whatever power management policy the user set up
for Host Initiated Power management (HIPM).
This power management policy will be activated after all
disks have been enumerated and intialized. Drivers should
also define disable_pm, which will turn off link power
management, but not change link power management policy.
Documentation/scsi/link_power_management_policy.txt has additional
information.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Some commands need post-processing after successful completion. This
was done in ata_scsi_qc_complete() till now but this has the following
problems.
* Post-command processing gets executed when qc is completed from EH.
Some qc's are retried from EH with zero err_mask and thus triggers
unnecessary/incorrect post-command processing.
* Command post processing doesn't belong to SAT layer.
* Link-wide revalidation was scheduled where device revalidation
suffices.
This patch moves post-command processing to success completion path of
ata_qc_complete() which is travelled iff the command is going to be
completed without passing through EH and updates post-command
processing such that device-specific action is used. While at it,
restructure code a bit for readability.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Tackle the relatively sane complaints of checkpatch --file.
The vast majority is indentation and whitespace changes, the rest are
* #include fixes
* printk KERN_xxx prefix addition
* BSS/initializer cleanups
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
LIBATA_MAX_PRD is the maximum number of DMA scatter/gather elements
permitted by the HBA's DMA engine. It's properly set to
q->max_hw_segments via the sg_tablesize parameter.
libata shouldn't call blk_queue_max_phys_segments. Now LIBATA_MAX_PRD
is equal to SCSI_MAX_PHYS_SEGMENTS by default (both is 128), so
everything is fine. But if they are changed, some code (like the scsi
mid layer, sg chaining, etc) might not work properly.
(Addition from Jens) The basic issue is that the physical segment
setting is purely a driver issue. And since SCSI is managing the sglist,
libata has no business changing the setting. All libata should care
about is the hw segment setting.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Fix libata docbook warnings.
Warning(linux-2.6.23-git8//drivers/ata/libata-scsi.c:3251): No description found for parameter 'dev'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After commands which can change device configuration, EH is scheduled
to revalidate and reconfigure the device. Host link was incorrectly
used unconditionally when scheduling EH action. This resulted in
bogus revalidation request and mismatched configuration between device
and driver. Fix it.
This bug was reported by Igor Durdanovic.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Igor Durdanovic <idurdanovic@comcast.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some controller variants snoop the ATAPI length value for Packet
transfers to do state machine and FIFO management. Thus we want to
set it properly, even for cases where it is otherwise meaningless.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
AN serves multiple purposes. For ATAPI, it's used for media change
notification. For PMP, for downstream PHY status change notification.
Implement sata_async_notification() which demultiplexes AN.
To avoid unnecessary port events, ATAPI AN is not enabled if PMP is
attached but SNTF is not available.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Kriten Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some pseudo devices fail PM commands unnecessarily aborting system
suspend. Implement ATA_HORKAGE_SKIP_PM which makes libata skip PM
commands for these devices.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Controllers which support PMP have various restrictions on which
combinations of commands are allowed to what number of devices
concurrently. This patch implements ops->qc_defer() which determines
whether a qc can be issued at the moment or should be deferred.
If the function returns ATA_DEFER_LINK, the qc will be deferred until
a qc completes on the link. If ATA_DEFER_PORT, until a qc completes
on any link. The defer conditions are advisory and in general
ATA_DEFER_LINK can be considered as lower priority deferring than
ATA_DEFER_PORT.
ops->qc_defer() replaces fixed ata_scmd_need_defer(). For standard
NCQ/non-NCQ exclusion, ata_std_qc_defer() is implemented. ahci and
sata_sil24 are converted to use ata_std_qc_defer().
ops->qc_defer() is heavier than the original mechanism because full qc
is prepped before determining to defer it, but various information is
needed to determine defer conditinos and fully translating a qc is the
only way to supply such information in generic manner.
IMHO, this shouldn't cause any noticeable performance issues as
* for most cases deferring occurs rarely (except for NCQ-aware
cmd-switching PMP)
* translation itself isn't that expensive
* once deferred the command won't be repeated until another command
completes which usually is a very long time cpu-wise.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update AN support in preparation of PMP support.
* s/ata_id_has_AN/ata_id_has_atapi_AN/
* add AN enabled reporting during configuration
* add err_mask to AN configuration failure reporting
* update LOCKING comment for ata_scsi_media_change_notify()
* check whether ATA dev is attached to SCSI dev ata_scsi_media_change_notify()
* set ATA_FLAG_AN in ahci and sata_sil24
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Kriten Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Clear ARRE, we don't do auto-reallocation on reads, just on writes.
Also, hardcode the size of the array using RW_RECOVERY_MPAGE_LEN,
following the style of the surrounding code.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* SAT specifies that FORMAT UNIT should be translated into a series
of READ and WRITE commands that zero the ATA device. That is far too
cumbersome to bother with.
Since we don't actually format the device, the old behavior of
always returning success was inaccurate. Change FORMAT UNIT from
returning success immediately (old behavior) to always returning
an error (new behavior).
* Add some comments around SYNCHRONIZE CACHE
* Shuffle scsi command code around a bit, so that things are close
to alphabetic order.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
A few pedantic apps care about missing or lame "mandatory" SCSI
commands, so
REQUEST SENSE -- as we autosense, R.S. just returns zeroes
SEND DIAGNOSTIC -- our default (no-op) self-test succeeds, all
other requests for testing fail.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
simple search-and-replace of direct scsi_cmnd access to
use the data buffer accessors.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This is a minimal patch needed to remove use of !use_sg
but it is not a complete clean up of the !use_sg paths.
Libata-core still has the qc->flags & ATA_QCFLAG_SG
and !qc->n_elem code paths. Perhaps an ata maintainer
would have a go at it.
- TODO: further cleanup of qc->flags & ATA_QCFLAG_SG
and !qc->n_elem code paths in libata-core
- TODO: Use scsi_dma_{map,unmap} where applicable.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
When we get an SDB FIS with the 'N' bit set, we should send
an event to user space to indicate that there has been a
media change. This will be done via the scsi device.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add support for issuing ATA_16 passthru commands to ATAPI devices
managed by libata. It requires the previous CDB length fix patch.
A boot/module parameter, "atapi_passthru16=0" can be used to globally
disable this feature, if ever desired.
tj: restructured __ata_scsi_queuecmd() according to Jeff's suggestion.
Signed-off-by: Mark Lord <liml@rtr.ca>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update hotplug to handle PMP links. When PMP is attached, the PMP
number corresponds to C of SCSI H:C:I:L. While at it, change argument
to ata_find_dev() to @devno from @id to avoid confusion with SCSI
device ID.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Multiple links and different number of devices per link should be
considered to iterate over links and devices. This patch implements
and uses link and device iterators - ata_port_for_each_link() and
ata_link_for_each_dev() - and ata_link_max_devices().
This change makes a lot of functions iterate over only possible
devices instead of from dev 0 to dev ATA_MAX_DEVICES. All such
changes have been examined and nothing should be broken.
While at it, add a separating comment before device helpers to
distinguish them better from link helpers and others.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Introduce ata_link. It abstracts PHY and sits between ata_port and
ata_device. This new level of abstraction is necessary to support
SATA Port Multiplier, which basically adds a bunch of links (PHYs) to
a ATA host port. Fields related to command execution, spd_limit and
EH are per-link and thus moved to ata_link.
This patch only defines the host link. Multiple link handling will be
added later. Also, a lot of ap->link derefences are added but many of
them will be removed as each part is converted to deal directly with
ata_link instead of ata_port.
This patch introduces no behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some of the code has been gradually transitioned to using the proper
struct request_queue, but there's lots left. So do a full sweet of
the kernel and get rid of this typedef and replace its uses with
the proper type.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
SCSI scan may fail due to memory allocation failure even if EH is not
in progress. Due to use of GFP_ATOMIC in SCSI scan path, allocation
failure isn't too rare especially while probing multiple devices at
once which is the case when a bunch of devices are connected to PMP.
This patch moves SCSI scan failure detetion logic from
ata_scsi_hotplug() to ata_scsi_scan_host() and implement synchronous
scan behavior. The synchronous path sleeps briefly and repeats SCSI
scan if some devices aren't attached properly. It contains robust
retry loop to minimize the chance of device misdetection during boot
and falls back to async retry if everything fails.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add ata_dumb_qc_prep and supporting logic so that a driver can just
specify it needs to be helped in this area. 64K entries are split
as with drivers/ide.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
In atapi_xlat(), prepare qc better before calling
ata_check_atapi_dma() such that ata_check_atapi_dma() can use info
from qc. While at it, reformat weird looking if/else block in the
function.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
INIT_DEV_PARAMS and SET_MULTI_MODE change the device parameters cached
by libata. Re-read IDENTIFY DEVICE info and update the cached device
paramters when seeing these commands.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Always enforce correct DEV bit since we know which drive the command
is targeted. SAT demands to ignore the DEV bit, too.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update the ATA passthru protocol numbers according to the new spec.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
With STANDBYDOWN tracking added, libata.spindown_compat isn't
necessary anymore. If userspace shutdown(8) issues STANDBYNOW, libata
warns. If userspace shutdown(8) doesn't issue STANDBYNOW, libata does
the right thing. Userspace can tell whether kernel supports spindown
by testing whether sysfs node manage_start_stop exists as before.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Our assumption that most distros issue STANDBYNOW seems wrong. The
upstream sysvinit and thus many distros including gentoo and opensuse
don't take any action for libata disks on spindown. We can skip
compat handling for these distros so that they don't need to update
anything to take advantage of kernel-side shutdown.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Unlocking ap->lock and ssleeping don't work because SCSI commands can
be issued from completion path without context. Reimplement delayed
completion by allowing translation functions to override
qc->scsidone(), storing the original completion function to
scmd->scsi_done() and overriding qc->scsidone() with a function which
schedules delayed invocation of scmd->scsi_done().
This isn't pretty at all but all the ugly parts are thankfully
contained in the stop translation path where the compat feature is
implemented.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Now that libata uses sd->manage_start_stop, libata spins down disk on
shutdown. In an attempt to compensate libata's previous shortcoming,
some distros sync and spin down disks attached via libata in their
shutdown(8). Some disks spin back up just to spin down again on
STANDBYNOW1 if the command is issued when the disk is spun down, so
this double spinning down causes problem.
This patch implements module parameter libata.spindown_compat which,
when set to one (default value), prevents libata from spinning down
disks on shutdown thus avoiding double spinning down. Note that
libata spins down disks for suspend to mem and disk, so with
libata.spindown_compat set to one, disks should be properly spun down
in all cases without modifying shutdown(8).
shutdown(8) should be fixed eventually. Some drive do spin up on
SYNCHRONZE_CACHE even when their cache is clean. Those disks
currently spin up briefly when sd tries to shutdown the device and
then the machine powers off immediately, which can't be good for the
head. We can't skip SYNCHRONIZE_CACHE during shudown as it can be
dangerous data integrity-wise.
So, this spindown_compat parameter is already scheduled for removal by
the end of the next year and here's what shutdown(8) should do.
* Check whether /sys/modules/libata/parameters/spindown_compat
exists. If it does, write 0 to it.
* For each libata harddisk {
* Check whether /sys/class/scsi_disk/h:c:i:l/manage_start_stop
exists. Iff it doesn't, synchronize cache and spin the disk
down as before.
}
The above procedure will make shutdown(8) work properly with kernels
before this change, ones with this workaround and later ones without
it.
To accelerate shutdown(8) updates, if the compat mode is in use, this
patch prints BIG FAT warning for five seconds during shutdown (the
optimal interval to annoy the user just the right amount discovered by
hours of tireless usability testing).
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Reimplement suspend/resume support using sdev->manage_start_stop.
* Device suspend/resume is now SCSI layer's responsibility and the
code is simplified a lot.
* DPM is dropped. This also simplifies code a lot. Suspend/resume
status is port-wide now.
* ata_scsi_device_suspend/resume() and ata_dev_ready() removed.
* Resume now has to wait for disk to spin up before proceeding. I
couldn't find easy way out as libata is in EH waiting for the
disk to be ready and sd is waiting for EH to complete to issue
START_STOP.
* sdev->manage_start_stop is set to 1 in ata_scsi_slave_config().
This fixes spindown on shutdown and suspend-to-disk.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Reorganize ata_host_alloc() and its subroutines into the following
three functions.
* ata_host_alloc() : allocates host and its ports. shost is not
registered automatically.
* ata_scsi_add_hosts() : allocates and adds shosts associated with an
ATA host. Used by ata_host_register().
* ata_host_register() : takes a fully initialized ata_host structure
and registers it to libata layer and probes it.
Only ata_host_alloc() and ata_host_register() are exported.
ata_device_add() is rewritten using the above functions. This patch
does not introduce any observable behavior change. Things worth
mentioning.
* print_id is assigned at registration time and LLDs are allowed to
overallocate ports and reduce host->n_ports during initialization.
ata_host_register() will throw away unused ports automatically.
* All SCSI host initialization stuff now resides in
ata_scsi_add_hosts() in libata-scsi.c, where it should be.
* ipr is now the only user of ata_host_init(). Either kill it by
converting ipr to use ata_host_alloc() and friends or rename and
move it to libata-scsi.c
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The READ/WRITE LONG commands are theoretically obsolete,
but the majority of drives in existance still implement them.
The WRITE_LONG and WRITE_LONG_ONCE commands are of particular
interest for fault injection testing -- eg. creating "media errors"
at specific locations on a disk.
The fussy bit is that these commands require a non-standard
sector size, usually 520 bytes instead of 512.
This patch adds support to libata for READ/WRITE LONG commands
issued via SG_IO/ATA_16.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Resending, with s/printk/DPRINTK/ as pointed out by Alan.
Fix libata to perform CDB len validation per device
rather than per host. This way, validation still works
when we have a mix of 12-byte and 16-byte devices on
a common host interface.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Preserve the LBA bit in the DevSel/Head register for HDIO_DRIVE_TASK.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
