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>
Conditionalize all PM related stuff in libata core layer using
CONFIG_PM.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_port has two different id fields - id and port_no. id is
system-wide 1-based unique id for the port while port_no is 0-based
host-wide port number. The former is primarily used to identify the
ATA port to the user in printk messages while the latter is used in
various places in libata core and LLDs to index the port inside the
host.
The two fields feel quite similar and sometimes ap->id is used in
place of ap->port_no, which is very difficult to spot. This patch
renames ap->id to ap->print_id to reduce the possibility of such bugs.
Some printk messages are adjusted such that id string (ata%u[.%u])
isn't printed twice and/or to use ata_*_printk() instead of hardcoded
id format.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix ata_scsi_change_queue_depth() such that...
* NCQ on/off is exactly determined using the same logic as the issue path.
* queue depth is adjusted to 1 if NCQ is not enabled.
* -EINVAL is returned if requested action is ignored due to limitations.
This fixes the bug which allows queue depth to be increased on
blacklisted NCQ hosts/devices.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix ata_scmd_need_defer() such that...
* whether NCQ is used or not is exactly determined using the same
criteria as the issue path.
* defer-check is performed in all cases.
This fixes race condition where turning off NCQ on the fly causes
non-NCQ commands sneak into NCQ phase.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_probe_ent_alloc() had a temporary hack such that devm_kzalloc()
was used for allocation if devres had been previously initialized on
the device; otherwise, plain kzalloc() was used. This was to make the
code useable from both the old and devres-aware libata drivers during
transition. This hack made ata_sas_port_alloc() unable to determine
how the probe_ent is allocated, causing double free in some cases.
Remove the now-unneeded hack and make ata_sas_port_alloc() use
devm_kfree().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
I was trying to use HDIO_DRIVE_TASK for something today,
and discovered that the libata implementation does not copy
over the upper four LBA bits from args[6].
This is serious, as any tools using this ioctl would have their
commands applied to the wrong sectors on the drive, possibly resulting
in disk corruption.
Ideally, newer apps should use SG_IO/ATA_16 directly,
avoiding this bug. But with libata poised to displace drivers/ide,
better compatibility here is a must.
This patch fixes libata to use the upper four LBA bits passed
in from the ioctl.
The original drivers/ide implementation copies over all bits
except for the master/slave select bit. With this patch,
libata will copy only the four high-order LBA bits,
just in case there are assumptions elsewhere in libata (?).
Signed-Off-By: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update libata core layer to use devres.
* ata_device_add() acquires all resources in managed mode.
* ata_host is allocated as devres associated with ata_host_release.
* Port attached status is handled as devres associated with
ata_host_attach_release().
* Initialization failure and host removal is handedl by releasing
devres group.
* Except for ata_scsi_release() removal, LLD interface remains the
same. Some functions use hacky is_managed test to support both
managed and unmanaged devices. These will go away once all LLDs are
updated to use devres.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
'hdparm -I' doesn't work with ATAPI devices and sg_sat is not widely
spread yet leaving no easy way to access ATAPI IDENTIFY data.
Implement HDIO_GET_IDENTITY such that at least 'hdparm -i' works.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
libata used two separate sets of variables to record request size and
current offset for ATA and ATAPI. This is confusing and fragile.
This patch replaces qc->nsect/cursect with qc->nbytes/curbytes and
kills them. Also, ata_pio_sector() is updated to use bytes for
qc->cursg_ofs instead of sectors. The field used to be used in bytes
for ATAPI and in sectors for ATA.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* Kill _OFS suffixes in ATA_ID_{SERNO|FW_REV|PROD}_OFS for consistency
with other ATA_ID_* constants.
* Kill ATA_SERNO_LEN
* Add and use ATA_ID_SERNO_LEN, ATA_ID_FW_REV_LEN and ATA_ID_PROD_LEN.
This change also makes ata_device_blacklisted() use proper length
for fwrev.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch makes the following needlessly global functions static:
- libata-core.c: ata_qc_complete_internal()
- libata-scsi.c: ata_scsi_qc_new()
- libata-scsi.c: ata_dump_status()
- libata-scsi.c: ata_to_sense_error()
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch introduces users of the round_jiffies() function: ATA subsystem
This delayed work is of the "about once a second" variety and can be rounded
to coincide with other wakers.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
libata's SCSI translation for the SCSI START STOP UNIT command with the
START bit clear (i.e. stopping the drive) appears to be incorrect. It
sends an ATA STANDBY command with the time period set to 0, which the code
comment says means "now", but the ATA standard says this means disable the
standby timer, which effectively does nothing. Change this to issue a
STANDBY IMMEDIATE command which will actually spin the drive down. The SAT
(SCSI/ATA Translation) standard revision 9 concurs with this choice.
Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
User applications using the HDIO_DRIVE_TASK ioctl through libata expect
specific ATA registers to be returned to userspace. Verified that
ata_task_ioctl correctly returns register values to the smartctl
application.
Signed-off-by: David Milburn <dmilburn@redhat.com>
Acked-by: Tejun Heo <htejun@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fixup the inialization of qc->n_elem. It currently gets
initialized to 1 for commands that do not transfer any data.
Fix this by initializing n_elem to 0 and only setting to 1
in ata_scsi_qc_new when there is data to transfer. This fixes
some problems seen with SATA devices attached to ipr adapters.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
libata depended on SCSI command to have the correct length when
tranlating it into an ATA command. This generally worked for commands
issued by SCSI HLD but user could issue arbitrary broken command using
sg interface.
Also, when building ATAPI command, full command size was always
copied. Because some ATAPI devices needs bytes after CDB cleared, if
upper layer doesn't clear bytes after CDB, such devices will
malfunction. This necessiated recent clear-garbage-after-CDB fix in
sg interfaces. However, scsi_execute() isn't fixed yet and HL-DT-ST
DVD-RAM GSA-H30N malfunctions on initialization commands issued from
SCSI.
This patch makes xlat functions always consider SCSI cmd_len. Each
translation function checks for proper cmd_len and ATAPI translaation
clears bytes after CDB.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Douglas Gilbert <dougg@torque.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
xlat function will be updated to consider qc->scsicmd->cmd_len and
many xlat functions deference qc->scsicmd already. It doesn't make
sense to pass qc->scsicmd->cmnd as @cdb separately. Kill the
argument.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Variable names in xlat functions are quite confusing now. 'scsicmd'
is used for CDB while qc->scsicmd points to struct scsi_cmnd while
'cmd' is used for struct scsi_cmnd.
This patch cleans up variable names in xlat functions such that 'scmd'
is used for struct scsi_cmnd and 'cdb' for CDB. Also, 'scmd' local
variable is added if qc->scsicmd is used multiple times.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Conflicts:
drivers/ata/libata-scsi.c
include/linux/libata.h
Futher merge of Linus's head and compilation fixups.
Signed-Off-By: David Howells <dhowells@redhat.com>
Conflicts:
drivers/infiniband/core/iwcm.c
drivers/net/chelsio/cxgb2.c
drivers/net/wireless/bcm43xx/bcm43xx_main.c
drivers/net/wireless/prism54/islpci_eth.c
drivers/usb/core/hub.h
drivers/usb/input/hid-core.c
net/core/netpoll.c
Fix up merge failures with Linus's head and fix new compilation failures.
Signed-Off-By: David Howells <dhowells@redhat.com>
Separate out rw ATA taskfile building from ata_scsi_rw_xlat() into
ata_build_rw_tf(). This will be used to improve media error handling.
Signed-off-by: Tejun Heo <htejun@gmail.com>
ata_scsi_dev_rescan() doesn't synchronize against SCSI device detach
and the target sdev might go away in the middle. Fix it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
* READ CAPACITY (16) implementation fixed. Result was shifted by two
bytes. Carlos Pardo spotted this problem and submitted preliminary
patch. Capacity => 2TB is handled correctly now. (verifid w/ fake
capacity)
* Use dev->n_sectors instead of re-reading directly from ID data.
* Define and use ATA_SCSI_RBUF_SET() which considers rbuf length.
This should be done for all simulation functions. Userland can
issue any simulated command with arbitrary buffer length.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Carlos Pardo <Carlos.Pardo@siliconimage.com>
Update ata_gen_ata_sense() to use desc format sense data to report the
first failed block. The first failed block is read from result_tf
using ata_tf_read_block() which can handle all three address formats.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* s/ata_gen_ata_desc_sense/ata_gen_passthru_sense/
* s/ata_gen_fixed_sense/ata_gen_ata_sense/
* make both functions static
* neither function has locking requirement, change it to None.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
sb[7] should contain the length of whole information sense data
descriptor while desc[1] should contain the number of following bytes
in the descriptor. ie. 14 for sb[7] but 12 for desc[1].
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Many drives support LBA48 even when its capacity is smaller than
1<<28, as LBA48 is required for many functionalities. FLUSH_EXT is
mandatory for drives w/ LBA48 support.
Interestingly, at least one of such drives (ST960812A) has problems
dealing with FLUSH_EXT. It eventually completes the command but takes
around 7 seconds to finish in many cases thus drastically slowing down
IO transactions. This seems to be a firmware bug which sneaked into
production probably because no other ATA driver including linux IDE
issues FLUSH_EXT to drives which report support for LBA48 & FLUSH_EXT
but is smaller than 1<<28 blocks.
This patch adds ATA_DFLAG_FLUSH_EXT which is set iff the drive
supports LBA48 & FLUSH_EXT and is larger than LBA28 limit. Both cache
flush paths are updated to issue FLUSH_EXT only when the flag is set.
Note that the changed behavior is more inline with the rest of libata.
libata prefers shorter commands whenever possible.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Danny Kukawka <dkukawka@novell.com>
Cc: Stefan Seyfried <seife@novell.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Move dev->max_sectors configuration from ata_scsi_dev_config() to
ata_dev_configure().
* more consistent.
* allows LLDs to peek at the default dev->max_sectors value.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make user scan wait for scan to complete. This way user can wait for
warm plug request to complete and is prevented from causing EH event
storm by repetitively issuing scan request while EH is in progress.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Fajun Chen <fajunchen@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fixes ata_sas_queuecmd to properly handle a failure from
__ata_scsi_queuecmd.
Signed-off-by: Brian King <brking@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Do not schedule EH for revalidation on wcache on/off if old EH. Old
EH cannot handle it and will result in WARN_ON()'s and oops.
This closes bug #7412.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.
For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.
To make this work, an extra flag is introduced into the management side of the
work_struct. This governs auto-release of the structure upon execution.
Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function. This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated.. This is a
problem if the auxiliary data is taken away (as done by the last patch).
However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems. But then the work function must itself release the
work_struct by calling work_release().
In most cases, automatic release is fine, so this is the default. Special
initiators exist for the non-auto-release case (ending in _NAR).
Signed-Off-By: David Howells <dhowells@redhat.com>
A curious thing happens, however, when ata_qc_new_init fails to get
an ata_queued_cmd:
First, ata_qc_new_init handles the failure like this:
cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
done(cmd);
Then, we return to ata_scsi_translate and do this:
err_mem:
cmd->result = (DID_ERROR << 16);
done(cmd);
It appears to me that first we set a status code indicating that we're
ok but the device queue is full and finish the command, but then
we blow away that status code and replace it with an error flag and
finish the command a second time! That does not seem to be desirable
behavior since we merely want the I/O to wait until a command slot
frees up, not send errors up the block layer.
In the err_mem case, we should simply exit out of ata_scsi_translate
instead.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make the HDIO_DRIVE_CMD ioctl in libata (ATA command pass through) return a
few ATA registers to userspace, following the same convention as the
drivers/ide implementation of the same ioctl. This is needed to support ATA
commands like CHECK POWER MODE, which return information in nsectors.
This fixes "hdparm -C" on SATA drives.
Forcing the sense data read via the cc flag causes spurious check conditions,
so we filter these out (following the ATA command pass-through specification
T10/04-262r7).
Signed-off-by: Eran Tromer <eran@tromer.org>
Acked-by: Tejun Heo <htejun@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The biggest change is that ata_host_set is renamed to ata_host.
* ata_host_set => ata_host
* ata_probe_ent->host_flags => ata_probe_ent->port_flags
* ata_probe_ent->host_set_flags => ata_probe_ent->_host_flags
* ata_host_stats => ata_port_stats
* ata_port->host => ata_port->scsi_host
* ata_port->host_set => ata_port->host
* ata_port_info->host_flags => ata_port_info->flags
* ata_(.*)host_set(.*)\(\) => ata_\1host\2()
The leading underscore in ata_probe_ent->_host_flags is to avoid
reusing ->host_flags for different purpose. Currently, the only user
of the field is libata-bmdma.c and probe_ent itself is scheduled to be
removed.
ata_port->host is reused for different purpose but this field is used
inside libata core proper and of different type.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>