linux-toradex.git/drivers/s390/block/scm_blk.c, branch v3.18.21

block: disable entropy contributions for nonrot devices

2014-10-04T16:55:32+00:00

Clear QUEUE_FLAG_ADD_RANDOM in all block drivers that set
QUEUE_FLAG_NONROT.

Historically, all block devices have automatically made entropy
contributions.  But as previously stated in commit e2e1a148 ("block: add
sysfs knob for turning off disk entropy contributions"):
    - On SSD disks, the completion times aren't as random as they
      are for rotational drives. So it's questionable whether they
      should contribute to the random pool in the first place.
    - Calling add_disk_randomness() has a lot of overhead.

There are more reliable sources for randomness than non-rotational block
devices.  From a security perspective it is better to err on the side of
caution than to allow entropy contributions from unreliable "random"
sources.

Signed-off-by: Mike Snitzer 
Signed-off-by: Jens Axboe

block: Convert bio_for_each_segment() to bvec_iter

2013-11-24T06:33:49+00:00

More prep work for immutable biovecs - with immutable bvecs drivers
won't be able to use the biovec directly, they'll need to use helpers
that take into account bio->bi_iter.bi_bvec_done.

This updates callers for the new usage without changing the
implementation yet.

Signed-off-by: Kent Overstreet 
Cc: Jens Axboe 
Cc: Geert Uytterhoeven 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: "Ed L. Cashin" 
Cc: Nick Piggin 
Cc: Lars Ellenberg 
Cc: Jiri Kosina 
Cc: Paul Clements 
Cc: Jim Paris 
Cc: Geoff Levand 
Cc: Yehuda Sadeh 
Cc: Sage Weil 
Cc: Alex Elder 
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris 
Cc: Philip Kelleher 
Cc: Konrad Rzeszutek Wilk 
Cc: Jeremy Fitzhardinge 
Cc: Neil Brown 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: linux390@de.ibm.com
Cc: Nagalakshmi Nandigama 
Cc: Sreekanth Reddy 
Cc: support@lsi.com
Cc: "James E.J. Bottomley" 
Cc: Greg Kroah-Hartman 
Cc: Alexander Viro 
Cc: Steven Whitehouse 
Cc: Herton Ronaldo Krzesinski 
Cc: Tejun Heo 
Cc: Andrew Morton 
Cc: Guo Chao 
Cc: Asai Thambi S P 
Cc: Selvan Mani 
Cc: Sam Bradshaw 
Cc: Matthew Wilcox 
Cc: Keith Busch 
Cc: Stephen Hemminger 
Cc: Quoc-Son Anh 
Cc: Sebastian Ott 
Cc: Nitin Gupta 
Cc: Minchan Kim 
Cc: Jerome Marchand 
Cc: Seth Jennings 
Cc: "Martin K. Petersen" 
Cc: Mike Snitzer 
Cc: Vivek Goyal 
Cc: "Darrick J. Wong" 
Cc: Chris Metcalf 
Cc: Jan Kara 
Cc: linux-m68k@lists.linux-m68k.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: drbd-user@lists.linbit.com
Cc: nbd-general@lists.sourceforge.net
Cc: cbe-oss-dev@lists.ozlabs.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: DL-MPTFusionLinux@lsi.com
Cc: linux-scsi@vger.kernel.org
Cc: devel@driverdev.osuosl.org
Cc: linux-fsdevel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: linux-mm@kvack.org
Acked-by: Geoff Levand

s390/scm_block: do not hide eadm subchannel dependency

2013-11-15T13:08:42+00:00

Stop hiding scm_block's dependency to the eadm subchannel driver
(by using functions provided by the eadm subchannel instead of
wrappers provided by the scm bus).

This will help userspace recognizing module dependencies (e.g. for
building a ramdisk). As a side effect we can get rid of some code
reimplementing refcounting between those modules.

Reported-by: Hendrik Brueckner 
Reviewed-by: Peter Oberparleiter 
Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky

s390/scm_blk: fix endless loop for requests != REQ_TYPE_FS

2013-11-06T13:32:22+00:00

The while loop only peeks at the top request in the queue but does
not yet consume it. Since we only handle fs requests, we need to
dequeue and complete all other request command types with error
just in case we would ever receive such an unforeseen request.

Signed-off-by: Steffen Maier 
Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky

block_device_operations->release() should return void

2013-05-07T06:16:21+00:00

The value passed is 0 in all but "it can never happen" cases (and those
only in a couple of drivers) *and* it would've been lost on the way
out anyway, even if something tried to pass something meaningful.
Just don't bother.

Signed-off-by: Al Viro

s390/scm_blk: fix memleak in init function

2013-04-26T07:07:17+00:00

If the allocation of a single request fails the already allocated
requests will not be freed.

Reviewed-by: Peter Oberparleiter 
Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky

s390/scm_blk: fix error return code in scm_blk_init()

2013-03-21T12:35:38+00:00

Fix to return a negative error code from the error handling
case instead of 0, as returned elsewhere in this function.

Signed-off-by: Wei Yongjun 
Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky

s390/scm_block: fix printk format string

2013-03-21T12:35:37+00:00

Use hex digits when referring to scm addresses.

Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky

s390/scm_blk: suspend writes

2013-03-07T08:52:23+00:00

Stop writing to scm after certain error conditions such as a concurrent
firmware upgrade. Resume to normal state once scm_blk_set_available is
called (due to an scm availability notification).

Reviewed-by: Peter Oberparleiter 
Signed-off-by: Sebastian Ott 
Signed-off-by: Peter Oberparleiter 
Signed-off-by: Martin Schwidefsky

s390/scm_blk: fix request number accounting

2013-03-07T08:52:20+00:00

If a block device driver cannot fetch all requests from the blocklayer
it's in his responsibility to call the request function at a later time.
Normally this would be done after the next irq for the underlying device
is handled. However in situations where we have no outstanding request
we have to schedule the request function for a later time.

This is determined using an internal counter of requests issued to the
hardware.

In some cases where we give a request back to the block layer unhandled
the number of queued requests was not adjusted. Fix this class of
failures by adjusting queued_requests in all functions used to give
a request back to the block layer.

Reviewed-by: Peter Oberparleiter 
Signed-off-by: Sebastian Ott 
Signed-off-by: Peter Oberparleiter 
Signed-off-by: Martin Schwidefsky