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167 Commits

Author SHA1 Message Date
James Bottomley
096cbc35ea Merge remote-tracking branch 'scsi-queue/drivers-for-3.19' into for-linus
Conflicts:
	drivers/scsi/scsi_debug.c

Agreed and tested resolution to a merge problem between a fix in scsi_debug
and a driver update

Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-12-08 07:42:25 -08:00
Christoph Hellwig
3af6b35261 scsi: remove scsi_driver owner field
The driver core driver structure has grown an owner field and now
requires it to be set for all modular drivers.  Set it up for
all scsi_driver instances and get rid of the now superflous
scsi_driver owner field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Shane M Seymour <shane.seymour@hp.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-24 20:01:28 +01:00
Christoph Hellwig
db5ed4dfd5 scsi: drop reason argument from ->change_queue_depth
Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-24 14:45:27 +01:00
Christoph Hellwig
c8b09f6fb6 scsi: don't set tagging state from scsi_adjust_queue_depth
Remove the tagged argument from scsi_adjust_queue_depth, and just let it
handle the queue depth.  For most drivers those two are fairly separate,
given that most modern drivers don't care about the SCSI "tagged" status
of a command at all, and many old drivers allow queuing of multiple
untagged commands in the driver.

Instead we start out with the ->simple_tags flag set before calling
->slave_configure, which is how all drivers actually looking at
->simple_tags except for one worke anyway.  The one other case looks
broken, but I've kept the behavior as-is for now.

Except for that we only change ->simple_tags from the ->change_queue_type,
and when rejecting a tag message in a single driver, so keeping this
churn out of scsi_adjust_queue_depth is a clear win.

Now that the usage of scsi_adjust_queue_depth is more obvious we can
also remove all the trivial instances in ->slave_alloc or ->slave_configure
that just set it to the cmd_per_lun default.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-11-12 11:19:43 +01:00
Christoph Hellwig
2ecb204d07 scsi: always assign block layer tags if enabled
Allow a driver to ask for block layer tags by setting .use_blk_tags in the
host template, in which case it will always see a valid value in
request->tag, similar to the behavior when using blk-mq.  This means even
SCSI "untagged" commands will now have a tag, which is especially useful
when using a host-wide tag map.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12 11:19:43 +01:00
Mark Knibbs
605c6dbef7 scsi: fix off-by-one LUN check in scsi_scan_host_selected()
The Scsi_Host structure max_lun field is the maximum allowed LUN plus 1. So
a LUN value is invalid if >= max_lun.

Signed-off-by: Mark Knibbs <markk@clara.co.uk>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-12 11:15:53 +01:00
Mark Knibbs
fb0d82f491 scsi: fix trivial typos in scsi_scan.c comment
Signed-off-by: Mark Knibbs <markk@clara.co.uk>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-12 11:15:52 +01:00
Subhash Jadavani
693ad5ba13 scsi: don't add scsi_device if its already visible
If LLD has added scsi device (by calling scsi_add_device) before scheduling
async scsi_scan_host then scsi_finish_async_scan() will end up calling
scsi_sysfs_add_sdev for scsi device which was already added by LLD.
This patch fixes this issue by skipping the call to scsi_sysfs_add_sdev()
if it's already visible to rest of the kernel.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-01 13:11:08 +02:00
Subhash Jadavani
45341ca3fc scsi: fix the type for well known LUs
Some devices may respond with wrong type for well-known logical units.
This patch forces well-known type for devices which doesn't report it
correct.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-01 13:11:03 +02:00
Alan Stern
50c4e96411 scsi: don't store LUN bits in CDB[1] for USB mass-storage devices
The SCSI specification requires that the second Command Data Byte
should contain the LUN value in its high-order bits if the recipient
device reports SCSI level 2 or below.  Nevertheless, some USB
mass-storage devices use those bits for other purposes in
vendor-specific commands.  Currently Linux has no way to send such
commands, because the SCSI stack always overwrites the LUN bits.

Testing shows that Windows 7 and XP do not store the LUN bits in the
CDB when sending commands to a USB device.  This doesn't matter if the
device uses the Bulk-Only or UAS transports (which virtually all
modern USB mass-storage devices do), as these have a separate
mechanism for sending the LUN value.

Therefore this patch introduces a flag in the Scsi_Host structure to
inform the SCSI midlayer that a transport does not require the LUN
bits to be stored in the CDB, and it makes usb-storage set this flag
for all devices using the Bulk-Only transport.  (UAS is handled by a
separate driver, but it doesn't really matter because no SCSI-2 or
lower device is at all likely to use UAS.)

The patch also cleans up the code responsible for storing the LUN
value by adding a bitflag to the scsi_device structure.  The test for
whether to stick the LUN value in the CDB can be made when the device
is probed, and stored for future use rather than being made over and
over in the fast path.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Tiziano Bacocco <tiziano.bacocco@gmail.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-09-15 16:01:58 -07:00
Janusz Dziemidowicz
0213436a2c scsi: do not issue SCSI RSOC command to Promise Vtrak E610f
Some devices don't like REPORT SUPPORTED OPERATION CODES and will
simply timeout causing sd_mod init to take a very very long time.
Introduce BLIST_NO_RSOC scsi scan flag, that stops RSOC from being
issued. Add it to Promise Vtrak E610f entry in scsi scan
blacklist. Fixes bug #79901 reported at
https://bugzilla.kernel.org/show_bug.cgi?id=79901

Fixes: 98dcc2946adb ("SCSI: sd: Update WRITE SAME heuristics")

Signed-off-by: Janusz Dziemidowicz <rraptorr@nails.eu.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-29 18:01:10 -04:00
Martin K. Petersen
c1d40a527e scsi: add a blacklist flag which enables VPD page inquiries
Despite supporting modern SCSI features some storage devices continue to
claim conformance to an older version of the SPC spec. This is done for
compatibility with legacy operating systems.

Linux by default will not attempt to read VPD pages on devices that
claim SPC-2 or older. Introduce a blacklist flag that can be used to
trigger VPD page inquiries on devices that are known to support them.

Reported-by: KY Srinivasan <kys@microsoft.com>
Tested-by: KY Srinivasan <kys@microsoft.com>
Reviewed-by: KY Srinivasan <kys@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25 17:16:41 -04:00
Christoph Hellwig
fd2eb9034e scsi: move the writeable field from struct scsi_device to struct scsi_cd
We currently set the field in common code based on the device type,
but then only use it in the cdrom driver which also overrides the
value previously set in the generic code.

Just leave this entirely to the CDROM driver to make everyones life
simpler.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-07-25 17:16:41 -04:00
Christoph Hellwig
d285203cf6 scsi: add support for a blk-mq based I/O path.
This patch adds support for an alternate I/O path in the scsi midlayer
which uses the blk-mq infrastructure instead of the legacy request code.

Use of blk-mq is fully transparent to drivers, although for now a host
template field is provided to opt out of blk-mq usage in case any unforseen
incompatibilities arise.

In general replacing the legacy request code with blk-mq is a simple and
mostly mechanical transformation.  The biggest exception is the new code
that deals with the fact the I/O submissions in blk-mq must happen from
process context, which slightly complicates the I/O completion handler.
The second biggest differences is that blk-mq is build around the concept
of preallocated requests that also include driver specific data, which
in SCSI context means the scsi_cmnd structure.  This completely avoids
dynamic memory allocations for the fast path through I/O submission.

Due the preallocated requests the MQ code path exclusively uses the
host-wide shared tag allocator instead of a per-LUN one.  This only
affects drivers actually using the block layer provided tag allocator
instead of their own.  Unlike the old path blk-mq always provides a tag,
although drivers don't have to use it.

For now the blk-mq path is disable by defauly and must be enabled using
the "use_blk_mq" module parameter.  Once the remaining work in the block
layer to make blk-mq more suitable for slow devices is complete I hope
to make it the default and eventually even remove the old code path.

Based on the earlier scsi-mq prototype by Nicholas Bellinger.

Thanks to Bart Van Assche and Robert Elliot for testing, benchmarking and
various sugestions and code contributions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
2014-07-25 17:16:28 -04:00
Hannes Reinecke
91921e016a scsi: use dev_printk variants where possible
Using dev_printk variants prefixes the logging message with
the originating device, which makes debugging easier.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17 22:07:42 +02:00
Hannes Reinecke
d9e5d61837 scsi_scan: Fixup scsilun_to_int()
scsilun_to_int() has an error which prevents it from generating
correct LUN numbers for 64bit values.
Also we should remove the misleading comment about portions of
the LUN being ignored; the initiator should treat the LUN as
an opaque value.
And, finally, the example given should use the correct
prefix (here: extended flat space addressing scheme).

This patch includes the modifications suggested by
Bart van Assche.

Cc: Bart van Assche <bvanassche@acm.org>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: James Bottomley <jbottomley@parallels.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17 22:07:39 +02:00
Hannes Reinecke
1abf635d2f scsi: use 64-bit value for 'max_luns'
Now that we're using 64-bit LUNs internally we need to increase
the size of max_luns to 64 bits, too.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17 22:07:38 +02:00
Hannes Reinecke
9cb78c16f5 scsi: use 64-bit LUNs
The SCSI standard defines 64-bit values for LUNs, and large arrays
employing large or hierarchical LUN numbers become more and more
common.

So update the linux SCSI stack to use 64-bit LUN numbers.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17 22:07:37 +02:00
Hannes Reinecke
22ffeb48b7 scsi_scan: Restrict sequential scan to 256 LUNs
Sequential scan for more than 256 LUNs is very fragile as
LUNs might not be numbered sequentially after that point.

SAM revisions later than SCSI-3 impose a structure on
LUNs larger than 256, making LUN numbers between 256
and 16384 illegal.
SCSI-3, however allows for plain 64-bit numbers with
no internal structure.

So restrict sequential LUN scan to 256 LUNs and add a
new blacklist flag 'BLIST_SCSI3LUN' to scan up to
max_lun devices.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17 22:07:35 +02:00
Hannes Reinecke
c309b35171 scsi: Remove CONFIG_SCSI_MULTI_LUN
Obsolete; either use 'max_lun' if the host supports only a
limited number of LUNs or BLIST_NOLUN if the target has
problems addressing more than one LUN.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17 22:07:35 +02:00
Linus Torvalds
b7e70ca9c7 Merge branch 'async-scsi-resume' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/isci
Pull async SCSI resume support from Dan Williams:
 "Allow disks and other devices to resume in parallel.

  This provides a tangible speed up for a non-esoteric use case (laptop
  resume):

    https://01.org/suspendresume/blogs/tebrandt/2013/hard-disk-resume-optimization-simpler-approach"

* 'async-scsi-resume' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/isci:
  scsi: async sd resume
2014-04-11 17:23:52 -07:00
Dan Williams
3c31b52f96 scsi: async sd resume
async_schedule() sd resume work to allow disks and other devices to
resume in parallel.

This moves the entirety of scsi_device resume to an async context to
ensure that scsi_device_resume() remains ordered with respect to the
completion of the start/stop command.  For the duration of the resume,
new command submissions (that do not originate from the scsi-core) will
be deferred (BLKPREP_DEFER).

It adds a new ASYNC_DOMAIN_EXCLUSIVE(scsi_sd_pm_domain) as a container
of these operations.  Like scsi_sd_probe_domain it is flushed at
sd_remove() time to ensure async ops do not continue past the
end-of-life of the sdev.  The implementation explicitly refrains from
reusing scsi_sd_probe_domain directly for this purpose as it is flushed
at the end of dpm_resume(), potentially defeating some of the benefit.
Given sdevs are quiesced it is permissible for these resume operations
to bleed past the async_synchronize_full() calls made by the driver
core.

We defer the resolution of which pm callback to call until
scsi_dev_type_{suspend|resume} time and guarantee that the callback
parameter is never NULL.  With this in place the type of resume
operation is encoded in the async function identifier.

There is a concern that async resume could trigger PSU overload.  In the
enterprise, storage enclosures enforce staggered spin-up regardless of
what the kernel does making async scanning safe by default.  Outside of
that context a user can disable asynchronous scanning via a kernel
command line or CONFIG_SCSI_SCAN_ASYNC.  Honor that setting when
deciding whether to do resume asynchronously.

Inspired by Todd's analysis and initial proposal [2]:
https://01.org/suspendresume/blogs/tebrandt/2013/hard-disk-resume-optimization-simpler-approach

Cc: Len Brown <len.brown@intel.com>
Cc: Phillip Susi <psusi@ubuntu.com>
[alan: bug fix and clean up suggestion]
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
[djbw: kick all resume work to the async queue]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2014-04-10 15:30:35 -07:00
Hannes Reinecke
b3ae8780b4 [SCSI] Add EVPD page 0x83 and 0x80 to sysfs
EVPD page 0x83 is used to uniquely identify the device.
So instead of having each and every program issue a separate
SG_IO call to retrieve this information it does make far more
sense to display it in sysfs.

Some older devices (most notably tapes) will only report reliable
information in page 0x80 (Unit Serial Number). So export this
in the sysfs attribute 'vpd_pg80'.

[jejb: checkpatch fix]
[hare: attach after transport configure]
[fengguang.wu@intel.com: spotted problems with the original now fixed]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-27 08:25:33 -07:00
James Bottomley
f2495e228f [SCSI] dual scan thread bug fix
In the highly unusual case where two threads are running concurrently through
the scanning code scanning the same target, we run into the situation where
one may allocate the target while the other is still using it.  In this case,
because the reap checks for STARGET_CREATED and kills the target without
reference counting, the second thread will do the wrong thing on reap.

Fix this by reference counting even creates and doing the STARGET_CREATED
check in the final put.

Tested-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org # delay backport for 2 months for field testing
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:18:59 -07:00
James Bottomley
e63ed0d7a9 [SCSI] fix our current target reap infrastructure
This patch eliminates the reap_ref and replaces it with a proper kref.
On last put of this kref, the target is removed from visibility in
sysfs.  The final call to scsi_target_reap() for the device is done from
__scsi_remove_device() and only if the device was made visible.  This
ensures that the target disappears as soon as the last device is gone
rather than waiting until final release of the device (which is often
too long).

Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org # delay backport by 2 months for field testing
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:18:59 -07:00
Martin K. Petersen
56f2a8016e [SCSI] Workaround for disks that report bad optimal transfer length
Not all disks fill out the VPD pages correctly. Add a blacklist flag
that allows us ignore the SBC-3 VPD pages for a given device. The
BLIST_SKIP_VPD_PAGES flag triggers our existing skip_vpd_pages
scsi_device parameter to bypass VPD scanning.

Also blacklist the offending Seagate drive model.

Reported-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-06-24 13:00:10 -07:00
Martin K. Petersen
0816c9251a [SCSI] Allow error handling timeout to be specified
Introduce eh_timeout which can be used for error handling purposes. This
was previously hardcoded to 10 seconds in the SCSI error handling
code. However, for some fast-fail scenarios it is necessary to be able
to tune this as it can take several iterations (bus device, target, bus,
controller) before we give up.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-06-04 11:16:24 -07:00
James Bottomley
fe709ed827 Merge SCSI misc branch into isci-for-3.6 tag 2012-10-02 08:55:12 +01:00
Martin K. Petersen
d974e4265d [SCSI] Disable DIF on Hitachi Ultrastar 15K300
Hitachi Ultrastar 15K300 is quirky. Disable T10 PI (DIF).

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-09-24 12:11:00 +04:00
James Bottomley
14216561e1 [SCSI] Fix 'Device not ready' issue on mpt2sas
This is a particularly nasty SCSI ATA Translation Layer (SATL) problem.

SAT-2 says (section 8.12.2)

        if the device is in the stopped state as the result of
        processing a START STOP UNIT command (see 9.11), then the SATL
        shall terminate the TEST UNIT READY command with CHECK CONDITION
        status with the sense key set to NOT READY and the additional
        sense code of LOGICAL UNIT NOT READY, INITIALIZING COMMAND
        REQUIRED;

mpt2sas internal SATL seems to implement this.  The result is very confusing
standby behaviour (using hdparm -y).  If you suspend a drive and then send
another command, usually it wakes up.  However, if the next command is a TEST
UNIT READY, the SATL sees that the drive is suspended and proceeds to follow
the SATL rules for this, returning NOT READY to all subsequent commands.  This
means that the ordering of TEST UNIT READY is crucial: if you send TUR and
then a command, you get a NOT READY to both back.  If you send a command and
then a TUR, you get GOOD status because the preceeding command woke the drive.

This bit us badly because

commit 85ef06d1d2
Author: Tejun Heo <tj@kernel.org>
Date:   Fri Jul 1 16:17:47 2011 +0200

    block: flush MEDIA_CHANGE from drivers on close(2)

Changed our ordering on TEST UNIT READY commands meaning that SATA drives
connected to an mpt2sas now suspend and refuse to wake (because the mpt2sas
SATL sees the suspend *before* the drives get awoken by the next ATA command)
resulting in lots of failed commands.

The standard is completely nuts forcing this inconsistent behaviour, but we
have to work around it.

The fix for this is twofold:

   1. Set the allow_restart flag so we wake the drive when we see it has been
      suspended

   2. Return all TEST UNIT READY status directly to the mid layer without any
      further error handling which prevents us causing error handling which
      may offline the device just because of a media check TUR.

Reported-by: Matthias Prager <linux@matthiasprager.de>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-08-22 09:42:54 +04:00
Dan Williams
e96eb23d82 [SCSI] Revert "[SCSI] fix async probe regression"
This reverts commit 43a8d39d01.

Commit 43a8d39d fixed the fact that wait_for_device_probe() was unable
to flush sd probe work.  Now that sd probe work is once again flushable
via wait_for_device_probe() this workaround is no longer needed.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 09:25:56 +01:00
Dan Williams
492d542273 [SCSI] cleanup usages of scsi_complete_async_scans
Now that scsi registers its async scan work with the async subsystem,
wait_for_device_probe() is sufficient for ensuring all scanning is
complete.

[jejb: fix merge problems with eea03c20ae Make wait_for_device_probe() also do scsi_complete_async_scans()]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 09:25:22 +01:00
Dan Williams
6cdd55205d [SCSI] queue async scan work to an async_schedule domain
This is preparation to enable async_synchronize_full() to be used as a
replacement for scsi_complete_async_scans(), i.e. to stop leaking scsi
internal details where they are not needed.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 09:09:27 +01:00
Dan Williams
3b661a92e8 [SCSI] fix hot unplug vs async scan race
The following crash results from cases where the end_device has been
removed before scsi_sysfs_add_sdev has had a chance to run.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
 IP: [<ffffffff8115e100>] sysfs_create_dir+0x32/0xb6
 ...
 Call Trace:
  [<ffffffff8125e4a8>] kobject_add_internal+0x120/0x1e3
  [<ffffffff81075149>] ? trace_hardirqs_on+0xd/0xf
  [<ffffffff8125e641>] kobject_add_varg+0x41/0x50
  [<ffffffff8125e70b>] kobject_add+0x64/0x66
  [<ffffffff8131122b>] device_add+0x12d/0x63a
  [<ffffffff814b65ea>] ? _raw_spin_unlock_irqrestore+0x47/0x56
  [<ffffffff8107de15>] ? module_refcount+0x89/0xa0
  [<ffffffff8132f348>] scsi_sysfs_add_sdev+0x4e/0x28a
  [<ffffffff8132dcbb>] do_scan_async+0x9c/0x145

...teach scsi_sysfs_add_devices() to check for deleted devices() before
trying to add them, and teach scsi_remove_target() how to remove targets
that have not been added via device_add().

Cc: <stable@vger.kernel.org>
Reported-by: Dariusz Majchrzak <dariusz.majchrzak@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:45 +01:00
Dan Williams
43a8d39d01 [SCSI] fix async probe regression
Commit a7a20d1 "[SCSI] sd: limit the scope of the async probe domain"
moved sd probe work out of reach of wait_for_device_probe().  Allow it
to be synced via scsi_complete_async_scans().

Reported-by: Meelis Roos <mroos@linux.ee>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-30 13:37:07 +04:00
Greg Kroah-Hartman
f7a0d426f3 Merge 3.3-rc7 into usb-next
This resolves the conflict with drivers/usb/host/ehci-fsl.h that
happened with changes in Linus's and this branch at the same time.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-12 09:13:31 -07:00
Huajun Li
267a6ad4ae [SCSI] scsi_scan: Fix 'Poison overwritten' warning caused by using freed 'shost'
In do_scan_async(), calling scsi_autopm_put_host(shost) may reference
freed shost, and cause Posison overwitten warning.
Yes, this case can happen, for example, an USB is disconnected just
when do_scan_async() thread starts to run, then scsi_host_put() called
in scsi_finish_async_scan() will lead to shost be freed(because the
refcount of shost->shost_gendev decreases to 1 after USB disconnects),
at this point, if references shost again, system will show following
warning msg.

To make scsi_autopm_put_host(shost) always reference a valid shost,
put it just before scsi_host_put() in function
scsi_finish_async_scan().

[  299.281565] =============================================================================
[  299.281634] BUG kmalloc-4096 (Tainted: G          I ): Poison overwritten
[  299.281682] -----------------------------------------------------------------------------
[  299.281684]
[  299.281752] INFO: 0xffff880056c305d0-0xffff880056c305d0. First byte
0x6a instead of 0x6b
[  299.281816] INFO: Allocated in scsi_host_alloc+0x4a/0x490 age=1688
cpu=1 pid=2004
[  299.281870] 	__slab_alloc+0x617/0x6c1
[  299.281901] 	__kmalloc+0x28c/0x2e0
[  299.281931] 	scsi_host_alloc+0x4a/0x490
[  299.281966] 	usb_stor_probe1+0x5b/0xc40 [usb_storage]
[  299.282010] 	storage_probe+0xa4/0xe0 [usb_storage]
[  299.282062] 	usb_probe_interface+0x172/0x330 [usbcore]
[  299.282105] 	driver_probe_device+0x257/0x3b0
[  299.282138] 	__driver_attach+0x103/0x110
[  299.282171] 	bus_for_each_dev+0x8e/0xe0
[  299.282201] 	driver_attach+0x26/0x30
[  299.282230] 	bus_add_driver+0x1c4/0x430
[  299.282260] 	driver_register+0xb6/0x230
[  299.282298] 	usb_register_driver+0xe5/0x270 [usbcore]
[  299.282337] 	0xffffffffa04ab03d
[  299.282364] 	do_one_initcall+0x47/0x230
[  299.282396] 	sys_init_module+0xa0f/0x1fe0
[  299.282429] INFO: Freed in scsi_host_dev_release+0x18a/0x1d0 age=85
cpu=0 pid=2008
[  299.282482] 	__slab_free+0x3c/0x2a1
[  299.282510] 	kfree+0x296/0x310
[  299.282536] 	scsi_host_dev_release+0x18a/0x1d0
[  299.282574] 	device_release+0x74/0x100
[  299.282606] 	kobject_release+0xc7/0x2a0
[  299.282637] 	kobject_put+0x54/0xa0
[  299.282668] 	put_device+0x27/0x40
[  299.282694] 	scsi_host_put+0x1d/0x30
[  299.282723] 	do_scan_async+0x1fc/0x2b0
[  299.282753] 	kthread+0xdf/0xf0
[  299.282782] 	kernel_thread_helper+0x4/0x10
[  299.282817] INFO: Slab 0xffffea00015b0c00 objects=7 used=7 fp=0x
      (null) flags=0x100000000004080
[  299.282882] INFO: Object 0xffff880056c30000 @offset=0 fp=0x          (null)
[  299.282884]
...

Signed-off-by: Huajun Li <huajun.li.lee@gmail.com>
Cc: stable@kernel.org
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-18 08:52:48 -06:00
Alan Stern
09b6b51b0b SCSI & usb-storage: add flags for VPD pages and REPORT LUNS
This patch (as1507) adds a skip_vpd_pages flag to struct scsi_device
and a no_report_luns flag to struct scsi_target.  The first is used to
control whether sd will look at VPD pages for information on block
provisioning, limits, and characteristics.  The second prevents
scsi_report_lun_scan() from issuing a REPORT LUNS command.

The patch also modifies usb-storage to set the new flag bits for all
USB devices and targets, and to stop adjusting the scsi_level value.

Historically we have seen that USB mass-storage devices often don't
support VPD pages or REPORT LUNS properly.  Until now we have avoided
these things by setting the scsi_level to SCSI_2 for all USB devices.
But this has the side effect of storing the LUN bits into the second
byte of each CDB, and now we have a report of a device which doesn't
like that.  The best solution is to stop abusing scsi_level and
instead have separate flags for VPD pages and REPORT LUNS.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Perry Wagle <wagle@mac.com>
CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-08 17:36:41 -08:00
Tejun Heo
09ac46c429 block: misc updates to blk_get_queue()
* blk_get_queue() is peculiar in that it returns 0 on success and 1 on
  failure instead of 0 / -errno or boolean.  Update it such that it
  returns %true on success and %false on failure.

* Make sure the caller checks for the return value.

* Separate out __blk_get_queue() which doesn't check whether @q is
  dead and put it in blk.h.  This will be used later.

This patch doesn't introduce any functional changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-12-14 00:33:38 +01:00
James Bottomley
4e6c82b361 [SCSI] fix WARNING: at drivers/scsi/scsi_lib.c:1704
On Mon, 2011-11-07 at 17:24 +1100, Stephen Rothwell wrote:
> Hi all,
>
> Starting some time last week I am getting the following during boot on
> our PPC970 blade:
>
> calling  .ipr_init+0x0/0x68 @ 1
> ipr: IBM Power RAID SCSI Device Driver version: 2.5.2 (April 27, 2011)
> ipr 0000:01:01.0: Found IOA with IRQ: 26
> ipr 0000:01:01.0: Starting IOA initialization sequence.
> ipr 0000:01:01.0: Adapter firmware version: 06160039
> ipr 0000:01:01.0: IOA initialized.
> scsi0 : IBM 572E Storage Adapter
> ------------[ cut here ]------------
> WARNING: at drivers/scsi/scsi_lib.c:1704
> Modules linked in:
> NIP: c00000000053b3d4 LR: c00000000053e5b0 CTR: c000000000541d70
> REGS: c0000000783c2f60 TRAP: 0700   Not tainted  (3.1.0-autokern1)
> MSR: 8000000000029032 <EE,ME,CE,IR,DR>  CR: 24002024  XER: 20000002
> TASK = c0000000783b8000[1] 'swapper' THREAD: c0000000783c0000 CPU: 0
> GPR00: 0000000000000001 c0000000783c31e0 c000000000cf38b0 c00000000239a9d0
> GPR04: c000000000cbe8f8 0000000000000000 c0000000783c3040 0000000000000000
> GPR08: c000000075daf488 c000000078a3b7ff c000000000bcacc8 0000000000000000
> GPR12: 0000000044002028 c000000007ffb000 0000000002e40000 000000000099b800
> GPR16: 0000000000000000 c000000000bba5fc c000000000a61db8 0000000000000000
> GPR20: 0000000001b77200 0000000000000000 c000000078990000 0000000000000001
> GPR24: c000000002396828 0000000000000000 0000000000000000 c000000078a3b938
> GPR28: fffffffffffffffa c0000000008ad2c0 c000000000c7faa8 c00000000239a9d0
> NIP [c00000000053b3d4] .scsi_free_queue+0x24/0x90
> LR [c00000000053e5b0] .scsi_alloc_sdev+0x280/0x2e0
> Call Trace:
> [c0000000783c31e0] [c000000000c7faa8] wireless_seq_fops+0x278d0/0x2eb88 (unreliable)
> [c0000000783c3270] [c00000000053e5b0] .scsi_alloc_sdev+0x280/0x2e0
> [c0000000783c3330] [c00000000053eba0] .scsi_probe_and_add_lun+0x390/0xb40
> [c0000000783c34a0] [c00000000053f7ec] .__scsi_scan_target+0x16c/0x650
> [c0000000783c35f0] [c00000000053fd90] .scsi_scan_channel+0xc0/0x100
> [c0000000783c36a0] [c00000000053fefc] .scsi_scan_host_selected+0x12c/0x1c0
> [c0000000783c3750] [c00000000083dcb4] .ipr_probe+0x2c0/0x390
> [c0000000783c3830] [c0000000003f50b4] .local_pci_probe+0x34/0x50
> [c0000000783c38a0] [c0000000003f5f78] .pci_device_probe+0x148/0x150
> [c0000000783c3950] [c0000000004e1e8c] .driver_probe_device+0xdc/0x210
> [c0000000783c39f0] [c0000000004e20cc] .__driver_attach+0x10c/0x110
> [c0000000783c3a80] [c0000000004e1228] .bus_for_each_dev+0x98/0xf0
> [c0000000783c3b30] [c0000000004e1bf8] .driver_attach+0x28/0x40
> [c0000000783c3bb0] [c0000000004e07d8] .bus_add_driver+0x218/0x340
> [c0000000783c3c60] [c0000000004e2a2c] .driver_register+0x9c/0x1b0
> [c0000000783c3d00] [c0000000003f62d4] .__pci_register_driver+0x64/0x140
> [c0000000783c3da0] [c000000000b99f88] .ipr_init+0x4c/0x68
> [c0000000783c3e20] [c00000000000ad24] .do_one_initcall+0x1a4/0x1e0
> [c0000000783c3ee0] [c000000000b512d0] .kernel_init+0x14c/0x1fc
> [c0000000783c3f90] [c000000000022468] .kernel_thread+0x54/0x70
> Instruction dump:
> ebe1fff8 7c0803a6 4e800020 7c0802a6 fba1ffe8 fbe1fff8 7c7f1b78 f8010010
> f821ff71 e8030398 3120ffff 7c090110 <0b000000> e86303b0 482de065 60000000
> ---[ end trace 759bed76a85e8dec ]---
> scsi 0:0:1:0: Direct-Access     IBM-ESXS MAY2036RC        T106 PQ: 0 ANSI: 5
> ------------[ cut here ]------------
>
> I get lots more of these.  The obvious commit to point the finger at
> is 3308511c93 ("[SCSI] Make scsi_free_queue() kill pending SCSI
> commands") but the root cause may be something different.

Caused by

commit f7c9c6bb14
Author: Anton Blanchard <anton@samba.org>
Date:   Thu Nov 3 08:56:22 2011 +1100

    [SCSI] Fix block queue and elevator memory leak in scsi_alloc_sdev

Doesn't completely do the teardown.  The true fix is to do a proper
teardown instead of hand rolling it

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: stable@kernel.org	#2.6.38+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-11-09 12:05:23 -06:00
Anton Blanchard
f7c9c6bb14 [SCSI] Fix block queue and elevator memory leak in scsi_alloc_sdev
When looking at memory consumption issues I noticed quite a
lot of memory in the kmalloc-2048 bucket:

  OBJS ACTIVE  USE OBJ SIZE  SLABS OBJ/SLAB CACHE SIZE NAME
  6561   6471  98%    2.30K    243       27     15552K kmalloc-2048

Over 15MB. slub debug shows that cfq is responsible for almost
all of it:

# sort -nr /sys/kernel/slab/kmalloc-2048/alloc_calls
6402 .cfq_init_queue+0xec/0x460 age=43423/43564/43655 pid=1 cpus=4,11,13

In scsi_alloc_sdev we do scsi_alloc_queue but if slave_alloc
fails we don't free it with scsi_free_queue.

The patch below fixes the issue:

  OBJS ACTIVE  USE OBJ SIZE  SLABS OBJ/SLAB CACHE SIZE NAME
   135     72  53%    2.30K      5       27       320K kmalloc-2048

# cat /sys/kernel/slab/kmalloc-2048/alloc_calls
3 .cfq_init_queue+0xec/0x460 age=3811/3876/3925 pid=1 cpus=4,11,13

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>		#2.6.38+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-11-03 11:19:50 +04:00
James Bottomley
e73e079bf1 [SCSI] Fix oops caused by queue refcounting failure
In certain circumstances, we can get an oops from a torn down device.
Most notably this is from CD roms trying to call scsi_ioctl.  The root
cause of the problem is the fact that after scsi_remove_device() has
been called, the queue is fully torn down.  This is actually wrong
since the queue can be used until the sdev release function is called.
Therefore, we add an extra reference to the queue which is released in
sdev->release, so the queue always exists.

Reported-by: Parag Warudkar <parag.lkml@gmail.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <jbottomley@parallels.com>
2011-06-02 18:34:43 +09:00
Jens Axboe
9937a5e2f3 scsi: remove performance regression due to async queue run
Commit c21e6beb removed our queue request_fn re-enter
protection, and defaulted to always running the queues from
kblockd to be safe. This was a known potential slow down,
but should be safe.

Unfortunately this is causing big performance regressions for
some, so we need to improve this logic. Looking into the details
of the re-enter, the real issue is on requeue of requests.

Requeue of requests upon seeing a BUSY condition from the device
ends up re-running the queue, causing traces like this:

scsi_request_fn()
        scsi_dispatch_cmd()
                scsi_queue_insert()
                        __scsi_queue_insert()
                                scsi_run_queue()
					scsi_request_fn()
						...

potentially causing the issue we want to avoid. So special
case the requeue re-run of the queue, but improve it to offload
the entire run of local queue and starved queue from a single
workqueue callback. This is a lot better than potentially
kicking off a workqueue run for each device seen.

This also fixes the issue of the local device going into recursion,
since the above mentioned commit never moved that queue run out
of line.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-17 11:04:44 +02:00
Kay Sievers
39aba963d9 driver core: remove CONFIG_SYSFS_DEPRECATED_V2 but keep it for block devices
This patch removes the old CONFIG_SYSFS_DEPRECATED_V2 config option,
but it keeps the logic around to handle block devices in the old manner
as some people like to run new kernel versions on old (pre 2007/2008)
distros.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: "James E.J. Bottomley" <James.Bottomley@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-22 10:16:43 -07:00
Alan Stern
bc4f24014d [SCSI] implement runtime Power Management
This patch (as1398b) adds runtime PM support to the SCSI layer.  Only
the machanism is provided; use of it is up to the various high-level
drivers, and the patch doesn't change any of them.  Except for sg --
the patch expicitly prevents a device from being runtime-suspended
while its sg device file is open.

The implementation is simplistic.  In general, hosts and targets are
automatically suspended when all their children are asleep, but for
them the runtime-suspend code doesn't actually do anything.  (A host's
runtime PM status is propagated up the device tree, though, so a
runtime-PM-aware lower-level driver could power down the host adapter
hardware at the appropriate times.)  There are comments indicating
where a transport class might be notified or some other hooks added.

LUNs are runtime-suspended by calling the drivers' existing suspend
handlers (and likewise for runtime-resume).  Somewhat arbitrarily, the
implementation delays for 100 ms before suspending an eligible LUN.
This is because there typically are occasions during bootup when the
same device file is opened and closed several times in quick
succession.

The way this all works is that the SCSI core increments a device's
PM-usage count when it is registered.  If a high-level driver does
nothing then the device will not be eligible for runtime-suspend
because of the elevated usage count.  If a high-level driver wants to
use runtime PM then it can call scsi_autopm_put_device() in its probe
routine to decrement the usage count and scsi_autopm_get_device() in
its remove routine to restore the original count.

Hosts, targets, and LUNs are not suspended while they are being probed
or removed, or while the error handler is running.  In fact, a fairly
large part of the patch consists of code to make sure that things
aren't suspended at such times.

[jejb: fix up compile issues in PM config variations]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-07-28 09:07:50 -05:00
Linus Torvalds
e2e2400bd4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6:
  [SCSI] fix race in scsi_target_reap
  [SCSI] aacraid: Eliminate use after free
  [SCSI] arcmsr: Support HW reset for EH and polling scheme for scsi device
  [SCSI] bfa: fix system crash when reading sysfs fc_host statistics
  [SCSI] iscsi_tcp: remove sk_sleep check
  [SCSI] ipr: improve interrupt service routine performance
  [SCSI] ipr: set the data list length in the request control block
  [SCSI] ipr: fix a register read to use the correct address for 64 bit adapters
  [SCSI] ipr: include the resource path in the IOA status area structure
  [SCSI] ipr: implement fixes for 64 bit adapter support
  [SCSI] be2iscsi: correct return value in mgmt_invalidate_icds()
2010-05-27 10:28:11 -07:00
Alan Stern
f9e8894ae5 [SCSI] fix race in scsi_target_reap
This patch (as1357) fixes a race in SCSI target allocation and
release.  Putting a target in the STARGET_DEL state isn't protected by
the host lock, so an old target structure could be reused by a new
device even though it's about to be deleted.  The cure is to change
the state while still holding the host lock.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-05-25 11:00:56 -05:00
Randy Dunlap
9f6aa5750d scsi_scan.c: fix/convert functions to use kernel-doc
scsi_scan.c: fix incorrectly formatted kernel-doc notation
& convert documentation of 2 functions into kernel-doc.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-24 07:31:20 -07:00
Alan Stern
12fb8c1574 [SCSI] don't kfree an initialized struct device
This patch (as1359) fixes a bug in scsi_alloc_target().  After a
device structure has been initialized (and especially after its name
has been set), it must not be freed directly.  One has to call
put_device() instead.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-04-11 09:24:15 -05:00
Tejun Heo
5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
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>
2010-03-30 22:02:32 +09:00