Shut up
drivers/message/fusion/mptsas.c: In function 'mptsas_event_process':
drivers/message/fusion/mptsas.c:5015: warning: unused variable 'log_info'
for configs with CONFIG_SCSI_MPT2SAS_LOGGING unset.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Acked-by: "Desai, Kashyap" <Kashyap.Desai@lsi.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Bus reset is not required for SAS Controller. It is valid for mptspi
and mptfc, but for mptsas it is not required. It is an extra work for
Error handling escallation for mptsas. Removing bus reset from error
handling will eventually speedup Error handling for SAS controller.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
SAS1.0 Controller was not able to detect SAS2.0 Expanders due to Link
RATE detection was limited to 1.5 Gbps and 3.0 Gbps for SAS1
controllers. Added detection for 6.0 Gbps link. Now, user can mix-up
6.0 Gpbs links with SAS1.0 controller.
e.g SAS1.0 HBA <----> SAS2.0 Expander <------> SAS2.0 Expander <--------> SAS1.0 Drive.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Conflicts:
MAINTAINERS
arch/arm/mach-omap2/pm24xx.c
drivers/scsi/bfa/bfa_fcpim.c
Needed to update to apply fixes for which the old branch was too
outdated.
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.
The patch below presents a simple SCSI host lock push-down as an
equivalent transformation. No locking or other behavior should change
with this patch. All existing bugs and locking orders are preserved.
Additionally, add one parameter to queuecommand,
struct Scsi_Host *
and remove one parameter from queuecommand,
void (*done)(struct scsi_cmnd *)
Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.
Minimal code disturbance was attempted with this change. Most drivers
needed only two one-line modifications for their host lock push-down.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Adding function name in original debug prints and few more debug prints are
added.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Issue description:
In multipath topology, when device deletion is in transient state,
multipath driver can call blk_flush_queue() as part of path failure.
Before device get deleted from OS, Device may go OFFLINE as part of error
handling kicked off triggered from multipathing driver. Above condition hits
more frequently if device missing delay timer (which is LSI specific firmware
parameter) is non zero value.
root cause of this issue is Error handling thread is getting kicked off for
device which is not really present(in transient state of deleting).
This patch has solution for this issue. driver is now using eh_timed_out
callback. See below.
mptsas_transport_template->eh_timed_out = mptsas_eh_timed_out
Using mptsas_eh_timed_out function, driver can decide weather vdevice is
under Device missing delay or deleting state.
for either of those cases, there is BLK_EH_RESET_TIMER return to scsi mid
and error handling thread will not be kicked off for that particular scsi
command.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Printing Doorbell register in a case of hard reset and timeout
should be useful for figuring out the state of the system.
Signed-off-by: Kei Tokunaga <tokunaga.keiich@jp.fujitsu.com>
Acked-by: "Desai, Kashyap" <Kashyap.Desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch fixes mptsas disk hot-removal processing. The
hot-removal processing doesn't complete because of this condition.
drivers/message/fusion/mptsas.c:
mptsas_taskmgmt_complete()
if ((mptsas_find_vtarget(ioc, channel, id)) && !ioc->fw_events_off)
mptsas_queue_device_delete(...);
mptsas_queue_device_delete(), which must be called for
hot-removal, never gets called because mptsas_find_vtarget()
always returns 0 here. At that time, the vtarget has already
been freed in mptsas_target_destroy(), and also the scsi_device
has been marked as SDEV_DEL.
As a result of the issue, port deletion functions won't get
called and the device ends up being in an incomplete state.
(Some data structures and sysfs entries, which should be
removed in hot-removal, remain.) One side effect of this is
that a hot-addition of the device (bringing the device back
on) fails.
This patch just removes mptsas_find_vtarget() from the if-state
condition.
Signed-off-by: Kei Tokunaga <tokunaga.keiich@jp.fujitsu.com>
Acked-by: "Desai, Kashyap" <Kashyap.Desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Issue: SATA hotplug does not work sometimes.
At the time of ADD device/ADD phys disk, drive may fail to add SATA device
due to temporary SAS Address for SATA device generated by firmware. Final
SAS address for SATA driver will be generated only after disk spinup is
done. This may take some times for slow spining SATA drives.
At phy link up driver gets attached device sas address and stores into
phyinfo. At the time of ADD event driver will read sas device page0 using
channel and FW ID provided in ADD Device event. Here in case of SATA drives,
driver will see miss match in phyinfo->sas_address and latest sas address
read from SAS DEVICE PAGE0 and eventually device won't be added to OS.
Fix:
When Driver read SAS DEVICE PAGE0, it can identify Device type looking at
device_info. If device is SATA drive and sas address mismatch happens,
Driver will do same stuffs which happened at the time of LINK UP to get
correct piece of information from Pages. ( Find parent device and refresh
parent device phys either HBA refresh/Exp refresh)
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Issue:
target reset will be queued to driver's internal queue to get schedule
later. When driver add target into internal target_reset queue we will block IOs
on those target using scsi midlayer API. Now due to some cause driver is not
executing those target_reset list and it is always in block state.
Changes:
now we are clearing target_reset queue from all other Callback context
instead of only DeviceReset context.Now wherever driver is clearing
taskmgmt_in_progress flag it is considering target_reset queue cleanup
also.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Added sanity check before treating any device is a valid device.
It is possible that firmware can have device page0 in its table, but that
devicemay not be available in topology. Device will be available in topology
only if there is Bus Target mapping is done in firmware. Driver will always
check B_T mapping of firmware before reporting device to upper layer.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
device missing delay is 8 bit value in io unit pg1. Making correct variable
declaration for device_missing_delay.
The driver is storing the calculated device missing delay in IOC structure
as a u8 instead of a u16. It needs to be a u16 if the delay is > 255.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Added proper error handling after mpt_config.
Now check of MPI_IOCSTATUS_CONFIG_INVALID_PAGE is added.
If error is MPI_IOCSTATUS_CONFIG_INVALID_PAGE, driver will return -ENODEV.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
1) Corrected name string as "MPT SAS HOST"
2) Added proper check conditions for MPT_MGMT_STATUS_COMMAND_GOOD.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Current design of mptsas is as follow.
MPTSAS will do probe() if pci id matches for available card in
system, irrespective of mode of controller. If controller is I/T mode
or I mode, things are fine. If controller is only in T mode, mptsas is
not doing complete process of mptsas_probe(). It will only make
sure IOC structure is created and IOC reference is available for
mptstm driver. Now While removing module we should take care
case of Target mode only mptsas. If we are removing IOC which is
only in Target mode, We should only detach IOC instead of
following rest of the cleanup process which is only required for T
mode controller. Now For T mode controller, only part clean up is
done instead of complete cleanup. mpt_detach will call early in case
of Target mode only controller.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Message Unit Reset - instructs the IOC to reset the Reply Post and
Free FIFO's. All the Message Frames on Reply Free FIFO are
discarded. All posted buffers are freed, and event notification is
turned off. IOC doesnt reply to any outstanding request. This will
transfer IOC to READY state. Message unit ready is less expensive
operations than Hard Reset. soft reset will not force Firmware to
reload again, it only do clean up of Message units.
mpt_Soft_Hard_ResetHandler will first try for Soft Reset,if
it fails then go for big hammer reset which is Hard Reset.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Add support to set the sdev state to SDEV_BLOCK during device removal
to stop IOs comming to the deleting driver immediately.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Added new function mptsas_exp_manufacture_info, which will
obtain the REPORT_MANUFACTURING, and fill the details into the
sas_expander_device object when the expander port is created.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Normally In HBA reset path MPT driver will flush existing work in current work
queue (mpt/0) . This is just a dummy activity for MPT driver point of
view, since HBA reset will turn off Work queue events.
It means we will simply returns from work queue without doing anything.
But for the case where Work is already done (half the way), we have to have
that work to be done.
Considering above condition we stuck forever since Deadlock in scsi midlayer
and MPT driver. sd_sync_cache() will wait forever since HBA is not in
Running state, and it will never come into Running state since
sd_sync_cache() is called from HBA reset context.
Now new code will not wait for half cooked work to be finished
before returning from HBA reset.
Once we are out of HBA reset, EH thread will change host state to running from
recovery and work waiting for running state of HBA will be finished.
New code is turning ON firmware event from another special work called
Rescan toplogy.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
On Big endian system kernel will crash due to address translation
is not handle properly.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Check for phyinfo->phy before calling sas_port_delete_phy.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Do not set max_id value received from FW. Once SAS transport layer is
introduced max_id value is missleading to SCSI mid layer. Use max_id to
infinite value.
logic of can queue of scsi host is changed.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Fix two typos in mptsas_not_responding_devices. It was mutex_lock instead
of unlock.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: "Desai, Kashyap" <Kashyap.Desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Conflicts:
drivers/message/fusion/mptsas.c
fixed up conflict between req->data_len accessors and mptsas driver updates.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Several of the doc book in the previous patches had incorrect multi-line short
function descriptors. Fixed it all to be the correct single line descriptor.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Firmware is able to handle Broadcast primitives, but upstream driver does not
have support for broadcast primitive handling. Now this patch is mainly to
support broadcast primitives.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
FW will report Queue full event to Driver and driver will handle this queue
full event to SCSI Mid layer.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
1. Handle integrated Raid device(Add/Delete) and error condition and check
related to Raid device. is_logical_volume will represent logical volume
device.
2. Raid device dual port support is added. Main functions to support this
feature are mpt_raid_phys_disk_get_num_paths and mpt_raid_phys_disk_pg1.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Resending patch considering Grants G's code review.
Main goal to submit this patch is code cleaup.
1. Better driver debug prints and code indentation.
2. fault_reset_work_lock is not used anywhere. driver is using taskmgmt_lock
instead of fault_reset_work_lock.
3. setting pci_set_drvdata properly.
4. Ingore config request when IOC is in reset state.( ioc_reset_in_progress
is set).
5. Init/clear managment frame proprely.(INITIALIZE_MGMT_STATUS and
CLEAR_MGMT_STATUS)
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
1.) SAS topology Rescan is added. If Firmware is doing Reset and we get
Device add interrupt from Firmware, we will not receive it as part of Reset
is going ON. After Reset we will do special Rescan of SAS topology.
2.) Driver version changed from 3.04.08 to 3.04.09.
Added proper lock/unlock in mptsas_not_responding_devices() as per James'
comment.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
SAS topology scan is restructured. HBA firmware is generating more
events. Expander Events are added, Link status events are also added with
respect to SAS topology scan optimization.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Now Firmware events are handled by firmware event queue.
Previously it was handled in interrupt context/WorkQueue of Linux.
Firmware Event handling is restructured and optimized.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
1) rewrite of ioctl_cmds internal generated function that issue commands to
firmware, porting them to be single threaded using the generic MPT_MGMT
struct. All wait Queues are replace by completion Queue.
2) added seperate callback handler for ioctl task managment
(mptctl_taskmgmt_reply), to handle command that timeout
3) rewrite mptctl_bus_reset
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
1.) Added taskmgmt_quiesce_io flag in IOC and removed resetPending from
_MPT_SCSI_HOST struct.
2.) Reset from Scsi mid layer and internal Reset are seperate context.
Adding DeviceResetCtx for internal Device reset frame.
mptsas_taskmgmt_complete is optimized as part of implementation.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Rewrite of all internal generated functions that issue commands to firmware,
porting them to be single threaded using the generic MPT_MGMT
struct. Implemented using completion Queue.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
1) Previously we had mutliple #defines to use same values.
Now those #defines are optimized.
MPT_IOCTL_STATUS_* is removed and MPT_MGMT_STATUS_* are new
#defines.
2.) config path is optimized.
Instead of wait Queue and timer, using completion Q.
3.) mpt_timer_expired is not used.
[jejb: elide patch to eliminate mpt_timer_expired]
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
sas_discovery_quiesce_io flag is used to control IO start/resume functionality.
IO will be stoped while doing discovery of topology. Once discovery is completed
It will resume IO. Resending patch including James review.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
The reason for this change is there is a data corruption when four different
physical memory regions in the 36GB to 37GB region are
accessed. This is only affecting 1078.
The solution is we need to use different addressing when filling in
the scatter gather table for the effected memory regions. So instead
of snooping on all four different memory holes, we treat any physical
addresses in the 36GB address with the same algorithm.
The fix is explained below
1) Ensure that the message frames are NOT located in the trouble
region. There is no remapping available for message frames, they must
be allocated outside the problem region.
2) Ensure that Sense buffers are NOT in the trouble region. There is
no remapping available.
3) Walk through the SGE entries and if any are inside the trouble region
then they need to be remapped as discussed below.
1) Set the Local Address bit in the SGE Flags field.
MPI_SGE_FLAGS_LOCAL_ADDRESS
2) Ensure we are using 64-bit SGEs
3) Set MSb (Bit 63) of the 64-bit address, this will indicate buffer
location is Host Memory.
Signed-off-by: Kashyap Desai <kadesai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
In commit c3a4d78c58, while introducing
rq->resid_len, the default value of residue count was changed from
full count to zero. The conversion was done under the assumption that
when a request fails residue count wasn't defined. However, Boaz and
James pointed out that this wasn't true and the residue count should
be preserved for failed requests too.
This patchset restores the original behavior by setting rq->resid_len
to blk_rq_bytes(rq) on request start and restoring explicit clearing
in affected drivers. While at it, take advantage of the fact that
rq->resid_len is set to full count where applicable.
* ide-cd: rq->resid_len cleared on pc success
* mptsas: req->resid_len cleared on success
* sas_expander: rsp/req->resid_len cleared on success
* mpt2sas_transport: req->resid_len cleared on success
* ide-cd, ide-tape, mptsas, sas_host_smp, mpt2sas_transport, ub: take
advantage of initial full count to simplify code
Boaz Harrosh spotted bug in resid_len initialization. Fixed as
suggested.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Borislav Petkov <petkovbb@googlemail.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
With recent unification of fields, it's now guaranteed that
rq->data_len always equals blk_rq_bytes(). Convert all non-IDE direct
users to accessors. IDE will be converted in a separate patch.
Boaz: spotted incorrect data_len/resid_len conversion in osd.
[ Impact: convert direct rq->data_len usages to blk_rq_bytes() ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
rq->data_len served two purposes - the length of data buffer on issue
and the residual count on completion. This duality creates some
headaches.
First of all, block layer and low level drivers can't really determine
what rq->data_len contains while a request is executing. It could be
the total request length or it coulde be anything else one of the
lower layers is using to keep track of residual count. This
complicates things because blk_rq_bytes() and thus
[__]blk_end_request_all() relies on rq->data_len for PC commands.
Drivers which want to report residual count should first cache the
total request length, update rq->data_len and then complete the
request with the cached data length.
Secondly, it makes requests default to reporting full residual count,
ie. reporting that no data transfer occurred. The residual count is
an exception not the norm; however, the driver should clear
rq->data_len to zero to signify the normal cases while leaving it
alone means no data transfer occurred at all. This reverse default
behavior complicates code unnecessarily and renders block PC on some
drivers (ide-tape/floppy) unuseable.
This patch adds rq->resid_len which is used only for residual count.
While at it, remove now unnecessasry blk_rq_bytes() caching in
ide_pc_intr() as rq->data_len is not changed anymore.
Boaz : spotted missing conversion in osd
Sergei : spotted too early conversion to blk_rq_bytes() in ide-tape
[ Impact: cleanup residual count handling, report 0 resid by default ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Borislav Petkov