<feed xmlns='http://www.w3.org/2005/Atom'>
<title>BMC/Intel-BMC/linux.git/block/bio-integrity.c, branch dev-4.6</title>
<subtitle>Intel OpenBMC Linux kernel source tree (mirror)</subtitle>
<id>https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-4.6</id>
<link rel='self' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-4.6'/>
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<updated>2015-12-09T15:04:29+00:00</updated>
<entry>
<title>blk-integrity: checking for NULL instead of IS_ERR</title>
<updated>2015-12-09T15:04:29+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2015-12-09T10:21:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=7b6c0f8034d78390f9185e2ec2edb0a3e4ad244e'/>
<id>urn:sha1:7b6c0f8034d78390f9185e2ec2edb0a3e4ad244e</id>
<content type='text'>
We recently changed bio_integrity_alloc() to return ERR_PTRs instead of
NULL but these calls were missed.

Fixes: 06c1e3902aa7 ('blk-integrity: empty implementation when disabled')
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Reviewed-by: Johannes Thumshirn &lt;jthumshirn@suse.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>blk-integrity: empty implementation when disabled</title>
<updated>2015-12-03T16:32:21+00:00</updated>
<author>
<name>Keith Busch</name>
<email>keith.busch@intel.com</email>
</author>
<published>2015-12-03T16:32:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=06c1e3902aa74b7432a7e82bb4a5aca233a42839'/>
<id>urn:sha1:06c1e3902aa74b7432a7e82bb4a5aca233a42839</id>
<content type='text'>
This patch moves the blk_integrity_payload definition outside the
CONFIG_BLK_DEV_INTERITY dependency and provides empty function
implementations when the kernel configuration disables integrity
extensions. This simplifies drivers that make use of these to map user
data so they don't need to repeat the same configuration checks.

Signed-off-by: Keith Busch &lt;keith.busch@intel.com&gt;

Updated by Jens to pass an error pointer return from
bio_integrity_alloc(), otherwise if CONFIG_BLK_DEV_INTEGRITY isn't
set, we return a weird ENOMEM from __nvme_submit_user_cmd()
if a meta buffer is set.

Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>block: blk_flush_integrity() for bio-based drivers</title>
<updated>2015-10-21T20:43:44+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2015-10-21T17:20:23+00:00</published>
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<id>urn:sha1:5a48fc147d7f2718a5c7e73bc8c4067235791fc1</id>
<content type='text'>
Since they lack requests to pin the request_queue active, synchronous
bio-based drivers may have in-flight integrity work from
bio_integrity_endio() that is not flushed by blk_freeze_queue().  Flush
that work to prevent races to free the queue and the final usage of the
blk_integrity profile.

This is temporary unless/until bio-based drivers start to generically
take a q_usage_counter reference while a bio is in-flight.

Cc: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
[martin: fix the CONFIG_BLK_DEV_INTEGRITY=n case]
Tested-by: Ross Zwisler &lt;ross.zwisler@linux.intel.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>block: Reduce the size of struct blk_integrity</title>
<updated>2015-10-21T20:42:39+00:00</updated>
<author>
<name>Martin K. Petersen</name>
<email>martin.petersen@oracle.com</email>
</author>
<published>2015-10-21T17:19:38+00:00</published>
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<id>urn:sha1:a48f041d91bf1aee599fa2adb53b780ed20c2ee5</id>
<content type='text'>
The per-device properties in the blk_integrity structure were previously
unsigned short. However, most of the values fit inside a char. The only
exception is the data interval size and we can work around that by
storing it as a power of two.

This cuts the size of the dynamic portion of blk_integrity in half.

Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Reported-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Sagi Grimberg &lt;sagig@mellanox.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>block: Consolidate static integrity profile properties</title>
<updated>2015-10-21T20:42:38+00:00</updated>
<author>
<name>Martin K. Petersen</name>
<email>martin.petersen@oracle.com</email>
</author>
<published>2015-10-21T17:19:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=0f8087ecdeac921fc4920f1328f55c15080bc6aa'/>
<id>urn:sha1:0f8087ecdeac921fc4920f1328f55c15080bc6aa</id>
<content type='text'>
We previously made a complete copy of a device's data integrity profile
even though several of the fields inside the blk_integrity struct are
pointers to fixed template entries in t10-pi.c.

Split the static and per-device portions so that we can reference the
template directly.

Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Reported-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Sagi Grimberg &lt;sagig@mellanox.com&gt;
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>block: Refuse adding appending a gapped integrity page to a bio</title>
<updated>2015-09-11T15:03:45+00:00</updated>
<author>
<name>Sagi Grimberg</name>
<email>sagig@mellanox.com</email>
</author>
<published>2015-09-08T15:33:35+00:00</published>
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<id>urn:sha1:87a816df537e096d404add543ef47b796906c130</id>
<content type='text'>
This is only theoretical at the moment given that the only
subsystems that generate integrity payloads are the block layer
itself and the scsi target (which generate well aligned integrity
payloads). But when we will expose integrity meta-data to user-space,
we'll need to refuse appending a page with a gap (if the queue
virtual boundary is set).

Signed-off-by: Sagi Grimberg &lt;sagig@mellanox.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>block: add a bi_error field to struct bio</title>
<updated>2015-07-29T14:55:15+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2015-07-20T13:29:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=4246a0b63bd8f56a1469b12eafeb875b1041a451'/>
<id>urn:sha1:4246a0b63bd8f56a1469b12eafeb875b1041a451</id>
<content type='text'>
Currently we have two different ways to signal an I/O error on a BIO:

 (1) by clearing the BIO_UPTODATE flag
 (2) by returning a Linux errno value to the bi_end_io callback

The first one has the drawback of only communicating a single possible
error (-EIO), and the second one has the drawback of not beeing persistent
when bios are queued up, and are not passed along from child to parent
bio in the ever more popular chaining scenario.  Having both mechanisms
available has the additional drawback of utterly confusing driver authors
and introducing bugs where various I/O submitters only deal with one of
them, and the others have to add boilerplate code to deal with both kinds
of error returns.

So add a new bi_error field to store an errno value directly in struct
bio and remove the existing mechanisms to clean all this up.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Reviewed-by: NeilBrown &lt;neilb@suse.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>bio integrity: do not assume bio_integrity_pool exists if bioset exists</title>
<updated>2015-07-07T13:46:47+00:00</updated>
<author>
<name>Mike Snitzer</name>
<email>snitzer@redhat.com</email>
</author>
<published>2015-07-01T16:57:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=bb8bd38b9a1685334b73e8c62e128cbedb875867'/>
<id>urn:sha1:bb8bd38b9a1685334b73e8c62e128cbedb875867</id>
<content type='text'>
bio_integrity_alloc() and bio_integrity_free() assume that if a bio was
allocated from a bioset that that bioset also had its bio_integrity_pool
allocated using bioset_integrity_create().  This is a very bad
assumption given that bioset_create() and bioset_integrity_create() are
completely disjoint.  Not all callers of bioset_create() have been
trained to also call bioset_integrity_create() -- and they may not care
to be.

Fix this by falling back to kmalloc'ing 'struct bio_integrity_payload'
rather than force all bioset consumers to (wastefully) preallocate a
bio_integrity_pool that they very likely won't actually need (given the
niche nature of the current block integrity support).

Otherwise, a NULL pointer "Kernel BUG" with a trace like the following
will be observed (as seen on s390x using zfcp storage) because dm-io
doesn't use bioset_integrity_create() when creating its bioset:

    [  791.643338] Call Trace:
    [  791.643339] ([&lt;00000003df98b848&gt;] 0x3df98b848)
    [  791.643341]  [&lt;00000000002c5de8&gt;] bio_integrity_alloc+0x48/0xf8
    [  791.643348]  [&lt;00000000002c6486&gt;] bio_integrity_prep+0xae/0x2f0
    [  791.643349]  [&lt;0000000000371e38&gt;] blk_queue_bio+0x1c8/0x3d8
    [  791.643355]  [&lt;000000000036f8d0&gt;] generic_make_request+0xc0/0x100
    [  791.643357]  [&lt;000000000036f9b2&gt;] submit_bio+0xa2/0x198
    [  791.643406]  [&lt;000003ff801f9774&gt;] dispatch_io+0x15c/0x3b0 [dm_mod]
    [  791.643419]  [&lt;000003ff801f9b3e&gt;] dm_io+0x176/0x2f0 [dm_mod]
    [  791.643423]  [&lt;000003ff8074b28a&gt;] do_reads+0x13a/0x1a8 [dm_mirror]
    [  791.643425]  [&lt;000003ff8074b43a&gt;] do_mirror+0x142/0x298 [dm_mirror]
    [  791.643428]  [&lt;0000000000154fca&gt;] process_one_work+0x18a/0x3f8
    [  791.643432]  [&lt;000000000015598a&gt;] worker_thread+0x132/0x3b0
    [  791.643435]  [&lt;000000000015d49a&gt;] kthread+0xd2/0xd8
    [  791.643438]  [&lt;00000000005bc0ca&gt;] kernel_thread_starter+0x6/0xc
    [  791.643446]  [&lt;00000000005bc0c4&gt;] kernel_thread_starter+0x0/0xc

Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>block: remove management of bi_remaining when restoring original bi_end_io</title>
<updated>2015-05-22T14:58:55+00:00</updated>
<author>
<name>Mike Snitzer</name>
<email>snitzer@redhat.com</email>
</author>
<published>2015-05-22T13:14:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=326e1dbb57368087a36607aaebe9795b8d5453e5'/>
<id>urn:sha1:326e1dbb57368087a36607aaebe9795b8d5453e5</id>
<content type='text'>
Commit c4cf5261 ("bio: skip atomic inc/dec of -&gt;bi_remaining for
non-chains") regressed all existing callers that followed this pattern:
 1) saving a bio's original bi_end_io
 2) wiring up an intermediate bi_end_io
 3) restoring the original bi_end_io from intermediate bi_end_io
 4) calling bio_endio() to execute the restored original bi_end_io

The regression was due to BIO_CHAIN only ever getting set if
bio_inc_remaining() is called.  For the above pattern it isn't set until
step 3 above (step 2 would've needed to establish BIO_CHAIN).  As such
the first bio_endio(), in step 2 above, never decremented __bi_remaining
before calling the intermediate bi_end_io -- leaving __bi_remaining with
the value 1 instead of 0.  When bio_inc_remaining() occurred during step
3 it brought it to a value of 2.  When the second bio_endio() was
called, in step 4 above, it should've called the original bi_end_io but
it didn't because there was an extra reference that wasn't dropped (due
to atomic operations being optimized away since BIO_CHAIN wasn't set
upfront).

Fix this issue by removing the __bi_remaining management complexity for
all callers that use the above pattern -- bio_chain() is the only
interface that _needs_ to be concerned with __bi_remaining.  For the
above pattern callers just expect the bi_end_io they set to get called!
Remove bio_endio_nodec() and also remove all bio_inc_remaining() calls
that aren't associated with the bio_chain() interface.

Also, the bio_inc_remaining() interface has been moved local to bio.c.

Fixes: c4cf5261 ("bio: skip atomic inc/dec of -&gt;bi_remaining for non-chains")
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
<entry>
<title>block: fix regression where bio_integrity_process uses wrong bio_vec iterator</title>
<updated>2014-12-02T15:15:21+00:00</updated>
<author>
<name>Darrick J. Wong</name>
<email>darrick.wong@oracle.com</email>
</author>
<published>2014-11-26T01:40:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=594416a72032684792bb22510c538098db10b750'/>
<id>urn:sha1:594416a72032684792bb22510c538098db10b750</id>
<content type='text'>
bio integrity handling is broken on a system with LVM layered atop a
DIF/DIX SCSI drive because device mapper clones the bio, modifies the
clone, and sends the clone to the lower layers for processing.
However, the clone bio has bi_vcnt == 0, which means that when the sd
driver calls bio_integrity_process to attach DIX data, the
for_each_segment_all() call (which uses bi_vcnt) returns immediately
and random garbage is sent to the disk on a disk write.  The disk of
course returns an error.

Therefore, teach bio_integrity_process() to use bio_for_each_segment()
to iterate the bio_vecs, since the per-bio iterator tracks which
bio_vecs are associated with that particular bio.  The integrity
handling code is effectively part of the "driver" (it's not the bio
owner), so it must use the correct iterator function.

v2: Fix a compiler warning about abandoned local variables.  This
patch supersedes "block: bio_integrity_process uses wrong bio_vec
iterator".  Patch applies against 3.18-rc6.

Signed-off-by: Darrick J. Wong &lt;darrick.wong@oracle.com&gt;
Acked-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@fb.com&gt;
</content>
</entry>
</feed>
