linux-toradex.git/net/ceph, branch v3.12.16

libceph: fix preallocation check in get_reply()

2014-03-31T12:22:36+00:00

commit f2be82b0058e90b5d9ac2cb896b4914276fb50ef upstream.

The check that makes sure that we have enough memory allocated to read
in the entire header of the message in question is currently busted.
It compares front_len of the incoming message with iov_len field of
ceph_msg::front structure, which is used primarily to indicate the
amount of data already read in, and not the size of the allocated
buffer.  Under certain conditions (e.g. a short read from a socket
followed by that socket's shutdown and owning ceph_connection reset)
this results in a warning similar to

[85688.975866] libceph: get_reply front 198 > preallocated 122 (4#0)

and, through another bug, leads to forever hung tasks and forced
reboots.  Fix this by comparing front_len with front_alloc_len field of
struct ceph_msg, which stores the actual size of the buffer.

Fixes: http://tracker.ceph.com/issues/5425

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

libceph: rename front to front_len in get_reply()

2014-03-31T12:22:35+00:00

commit 3f0a4ac55fe036902e3666be740da63528ad8639 upstream.

Rename front local variable to front_len in get_reply() to make its
purpose more clear.

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

libceph: rename ceph_msg::front_max to front_alloc_len

2014-03-31T12:22:35+00:00

commit 3cea4c3071d4e55e9d7356efe9d0ebf92f0c2204 upstream.

Rename front_max field of struct ceph_msg to front_alloc_len to make
its purpose more clear.

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

libceph: resend all writes after the osdmap loses the full flag

2014-03-31T12:22:27+00:00

commit 9a1ea2dbff11547a8e664f143c1ffefc586a577a upstream.

With the current full handling, there is a race between osds and
clients getting the first map marked full. If the osd wins, it will
return -ENOSPC to any writes, but the client may already have writes
in flight. This results in the client getting the error and
propagating it up the stack. For rbd, the block layer turns this into
EIO, which can cause corruption in filesystems above it.

To avoid this race, osds are being changed to drop writes that came
from clients with an osdmap older than the last osdmap marked full.
In order for this to work, clients must resend all writes after they
encounter a full -> not full transition in the osdmap. osds will wait
for an updated map instead of processing a request from a client with
a newer map, so resent writes will not be dropped by the osd unless
there is another not full -> full transition.

This approach requires both osds and clients to be fixed to avoid the
race. Old clients talking to osds with this fix may hang instead of
returning EIO and potentially corrupting an fs. New clients talking to
old osds have the same behavior as before if they encounter this race.

Fixes: http://tracker.ceph.com/issues/6938

Reviewed-by: Sage Weil 
Signed-off-by: Josh Durgin 
Signed-off-by: Jiri Slaby

libceph: block I/O when PAUSE or FULL osd map flags are set

2014-03-31T12:22:27+00:00

commit d29adb34a94715174c88ca93e8aba955850c9bde upstream.

The PAUSEWR and PAUSERD flags are meant to stop the cluster from
processing writes and reads, respectively. The FULL flag is set when
the cluster determines that it is out of space, and will no longer
process writes.  PAUSEWR and PAUSERD are purely client-side settings
already implemented in userspace clients. The osd does nothing special
with these flags.

When the FULL flag is set, however, the osd responds to all writes
with -ENOSPC. For cephfs, this makes sense, but for rbd the block
layer translates this into EIO.  If a cluster goes from full to
non-full quickly, a filesystem on top of rbd will not behave well,
since some writes succeed while others get EIO.

Fix this by blocking any writes when the FULL flag is set in the osd
client. This is the same strategy used by userspace, so apply it by
default.  A follow-on patch makes this configurable.

__map_request() is called to re-target osd requests in case the
available osds changed.  Add a paused field to a ceph_osd_request, and
set it whenever an appropriate osd map flag is set.  Avoid queueing
paused requests in __map_request(), but force them to be resent if
they become unpaused.

Also subscribe to the next osd map from the monitor if any of these
flags are set, so paused requests can be unblocked as soon as
possible.

Fixes: http://tracker.ceph.com/issues/6079

Reviewed-by: Sage Weil 
Signed-off-by: Josh Durgin 
Signed-off-by: Jiri Slaby

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

2013-09-19T17:50:37+00:00

Pull ceph fixes from Sage Weil:
 "These fix several bugs with RBD from 3.11 that didn't get tested in
  time for the merge window: some error handling, a use-after-free, and
  a sequencing issue when unmapping and image races with a notify
  operation.

  There is also a patch fixing a problem with the new ceph + fscache
  code that just went in"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  fscache: check consistency does not decrement refcount
  rbd: fix error handling from rbd_snap_name()
  rbd: ignore unmapped snapshots that no longer exist
  rbd: fix use-after free of rbd_dev->disk
  rbd: make rbd_obj_notify_ack() synchronous
  rbd: complete notifies before cleaning up osd_client and rbd_dev
  libceph: add function to ensure notifies are complete

libceph: add function to ensure notifies are complete

2013-09-09T18:15:49+00:00

Without a way to flush the osd client's notify workqueue, a watch
event that is unregistered could continue receiving callbacks
indefinitely.

Unregistering the event simply means no new notifies are added to the
queue, but there may still be events in the queue that will call the
watch callback for the event. If the queue is flushed after the event
is unregistered, the caller can be sure no more watch callbacks will
occur for the canceled watch.

Signed-off-by: Josh Durgin 
Reviewed-by: Sage Weil 
Reviewed-by: Alex Elder

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

2013-09-09T16:13:22+00:00

Pull ceph updates from Sage Weil:
 "This includes both the first pile of Ceph patches (which I sent to
  torvalds@vger, sigh) and a few new patches that add support for
  fscache for Ceph.  That includes a few fscache core fixes that David
  Howells asked go through the Ceph tree.  (Thanks go to Milosz Tanski
  for putting this feature together)

  This first batch of patches (included here) had (has) several
  important RBD bug fixes, hole punch support, several different
  cleanups in the page cache interactions, improvements in the truncate
  code (new truncate mutex to avoid shenanigans with i_mutex), and a
  series of fixes in the synchronous striping read/write code.

  On top of that is a random collection of small fixes all across the
  tree (error code checks and error path cleanup, obsolete wq flags,
  etc)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (43 commits)
  ceph: use d_invalidate() to invalidate aliases
  ceph: remove ceph_lookup_inode()
  ceph: trivial buildbot warnings fix
  ceph: Do not do invalidate if the filesystem is mounted nofsc
  ceph: page still marked private_2
  ceph: ceph_readpage_to_fscache didn't check if marked
  ceph: clean PgPrivate2 on returning from readpages
  ceph: use fscache as a local presisent cache
  fscache: Netfs function for cleanup post readpages
  FS-Cache: Fix heading in documentation
  CacheFiles: Implement interface to check cache consistency
  FS-Cache: Add interface to check consistency of a cached object
  rbd: fix null dereference in dout
  rbd: fix buffer size for writes to images with snapshots
  libceph: use pg_num_mask instead of pgp_num_mask for pg.seed calc
  rbd: fix I/O error propagation for reads
  ceph: use vfs __set_page_dirty_nobuffers interface instead of doing it inside filesystem
  ceph: allow sync_read/write return partial successed size of read/write.
  ceph: fix bugs about handling short-read for sync read mode.
  ceph: remove useless variable revoked_rdcache
  ...

libceph: use pg_num_mask instead of pgp_num_mask for pg.seed calc

2013-09-04T05:08:10+00:00

Fix a typo that used the wrong bitmask for the pg.seed calculation.  This
is normally unnoticed because in most cases pg_num == pgp_num.  It is, however,
a bug that is easily corrected.

CC: stable@vger.kernel.org
Signed-off-by: Sage Weil 
Reviewed-by: Alex Elder

libceph: create_singlethread_workqueue() doesn't return ERR_PTRs

2013-08-27T19:26:31+00:00

create_singlethread_workqueue() returns NULL on error, and it doesn't
return ERR_PTRs.

I tweaked the error handling a little to be consistent with earlier in
the function.

Signed-off-by: Dan Carpenter 
Reviewed-by: Sage Weil