linux-stable.git/drivers/block, branch v3.18.6

rbd: fix rbd_dev_parent_get() when parent_overlap == 0

2015-02-06T06:36:04+00:00

commit ae43e9d05eb4bd324155292f889fbd001c4faea8 upstream.

The comment for rbd_dev_parent_get() said

    * We must get the reference before checking for the overlap to
    * coordinate properly with zeroing the parent overlap in
    * rbd_dev_v2_parent_info() when an image gets flattened.  We
    * drop it again if there is no overlap.

but the "drop it again if there is no overlap" part was missing from
the implementation.  This lead to absurd parent_ref values for images
with parent_overlap == 0, as parent_ref was incremented for each
img_request and virtually never decremented.

Fix this by leveraging the fact that refresh path calls
rbd_dev_v2_parent_info() under header_rwsem and use it for read in
rbd_dev_parent_get(), instead of messing around with atomics.  Get rid
of barriers in rbd_dev_v2_parent_info() while at it - I don't see what
they'd pair with now and I suspect we are in a pretty miserable
situation as far as proper locking goes regardless.

Signed-off-by: Ilya Dryomov 
Reviewed-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: drop parent_ref in rbd_dev_unprobe() unconditionally

2015-02-06T06:36:04+00:00

commit e69b8d414f948c242ad9f3eb2b7e24fba783dbbd upstream.

This effectively reverts the last hunk of 392a9dad7e77 ("rbd: detect
when clone image is flattened").

The problem with parent_overlap != 0 condition is that it's possible
and completely valid to have an image with parent_overlap == 0 whose
parent state needs to be cleaned up on unmap.  The next commit, which
drops the "clone image now standalone" logic, opens up another window
of opportunity to hit this, but even without it

    # cat parent-ref.sh
    #!/bin/bash
    rbd create --image-format 2 --size 1 foo
    rbd snap create foo@snap
    rbd snap protect foo@snap
    rbd clone foo@snap bar
    rbd resize --allow-shrink --size 0 bar
    rbd resize --size 1 bar
    DEV=$(rbd map bar)
    rbd unmap $DEV

leaves rbd_device/rbd_spec/etc and rbd_client along with ceph_client
hanging around.

My thinking behind calling rbd_dev_parent_put() unconditionally is that
there shouldn't be any requests in flight at that point in time as we
are deep into unmap sequence.  Hence, even if rbd_dev_unparent() caused
by flatten is delayed by in-flight requests, it will have finished by
the time we reach rbd_dev_unprobe() caused by unmap, thus turning
unconditional rbd_dev_parent_put() into a no-op.

Fixes: http://tracker.ceph.com/issues/10352

Signed-off-by: Ilya Dryomov 
Reviewed-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

drbd: Fix state change in case of connection timeout

2015-01-16T14:59:52+00:00

commit 9581f97a687724ea41cf2e145dda4751161198c1 upstream.

A connection timeout affects all volumes of a resource!
Under the following conditions:

 A resource with multiple volumes
  AND
 ko-count >=1
  AND
 a write request triggers the timeout (ko-count * timeout)

DRBD's internal state gets confused. That in turn may
lead to very miss leading follow up failures. E.g.
"BUG: scheduling while atomic"

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

drbd: merge_bvec_fn: properly remap bvm->bi_bdev

2015-01-16T14:59:52+00:00

commit 3b9d35d744bb5139f9fed57f38c019bb8c7d351c upstream.

This was not noticed for many years. Affects operation if
md raid is used a backing device for DRBD.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

zram: avoid kunmap_atomic() of a NULL pointer

2014-11-14T00:17:05+00:00

zram could kunmap_atomic() a NULL pointer in a rare situation: a zram
page becomes a full-zeroed page after a partial write io.  The current
code doesn't handle this case and performs kunmap_atomic() on a NULL
pointer, which panics the kernel.

This patch fixes this issue.

Signed-off-by: Weijie Yang 
Cc: Sergey Senozhatsky 
Cc: Dan Streetman 
Cc: Nitin Gupta 
Cc: Weijie Yang 
Acked-by: Jerome Marchand 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

2014-11-03T23:04:26+00:00

Pull ceph fixes from Sage Weil:
 "There is a GFP flag fix from Mike Christie, an error code fix from
  Jan, and fixes for two unnecessary allocations (kmalloc and workqueue)
  from Ilya.  All are well tested.

  Ilya has one other fix on the way but it didn't get tested in time"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  libceph: eliminate unnecessary allocation in process_one_ticket()
  rbd: Fix error recovery in rbd_obj_read_sync()
  libceph: use memalloc flags for net IO
  rbd: use a single workqueue for all devices

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

2014-10-31T22:00:48+00:00

Pull sparc update from David Miller:
 "Two changes:

  1) It makes no sense to execute a VTOC partition table request in the
     Sun virtual block device driver and fail to load if it doesn't
     succeed because a) we don't use the result at all and b) it won't
     succeed if there is an EFI partition on the disk, for example.

     We read the partition table via the normal means in the block layer
     anyways, so this is really completely useless, so just remove it.

     From Dwight Engen.

  2) Hook up new bpf system call"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sunvdc: don't call VD_OP_GET_VTOC
  sparc: Hook up bpf system call.

sunvdc: don't call VD_OP_GET_VTOC

2014-10-31T19:49:45+00:00

The VD_OP_GET_VTOC operation will succeed only if the vdisk backend has a
VTOC label, otherwise it will fail. In particular, it will return error
48 (ENOTSUP) if the disk has an EFI label. VTOC disk labels are already
handled by directly reading the disk in block/partitions/sun.c (enabled by
CONFIG_SUN_PARTITION which defaults to y on SPARC). Since port->label is
unused in the driver, remove the call and the field.

Signed-off-by: Dwight Engen 
Signed-off-by: David S. Miller

rbd: Fix error recovery in rbd_obj_read_sync()

2014-10-30T10:11:51+00:00

When we fail to allocate page vector in rbd_obj_read_sync() we just
basically ignore the problem and continue which will result in an oops
later. Fix the problem by returning proper error.

CC: Yehuda Sadeh 
CC: Sage Weil 
CC: ceph-devel@vger.kernel.org
CC: stable@vger.kernel.org
Coverity-id: 1226882
Signed-off-by: Jan Kara 
Signed-off-by: Ilya Dryomov

rbd: use a single workqueue for all devices

2014-10-30T10:11:25+00:00

Using one queue per device doesn't make much sense given that our
workfn processes "devices" and not "requests".  Switch to a single
workqueue for all devices.

Signed-off-by: Ilya Dryomov 
Reviewed-by: Sage Weil