linux-toradex.git/drivers/block/rbd.c, branch v3.14.35 Linux kernel for Apalis and Colibri modules rbd: fix rbd_dev_parent_get() when parent_overlap == 0 2015-02-06T06:35:52+00:00 Ilya Dryomov idryomov@redhat.com 2015-01-19T15:13:43+00:00 b49e4a878abbfdb9c12e4170a61a9a01dbdd6328 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 <idryomov@redhat.com> Reviewed-by: Josh Durgin <jdurgin@redhat.com> Reviewed-by: Alex Elder <elder@linaro.org> [idryomov@redhat.com: backport to 3.14: context] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <idryomov@redhat.com>
Reviewed-by: Josh Durgin <jdurgin@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>
[idryomov@redhat.com: backport to 3.14: context]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rbd: drop parent_ref in rbd_dev_unprobe() unconditionally 2015-02-06T06:35:49+00:00 Ilya Dryomov idryomov@redhat.com 2015-01-19T09:06:14+00:00 1027dfa58f3655ee5a2309b44ce5be637fd621fd 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 <idryomov@redhat.com> Reviewed-by: Josh Durgin <jdurgin@redhat.com> Reviewed-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <idryomov@redhat.com>
Reviewed-by: Josh Durgin <jdurgin@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rbd: Fix error recovery in rbd_obj_read_sync() 2014-11-14T17:00:12+00:00 Jan Kara jack@suse.cz 2014-10-22T07:17:24+00:00 9b5d484b3846217256cf6b05883ac1469c32eebe commit a8d4205623ae965e36c68629db306ca0695a2771 upstream. 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 <yehuda@inktank.com> CC: Sage Weil <sage@inktank.com> CC: ceph-devel@vger.kernel.org Coverity-id: 1226882 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Ilya Dryomov <idryomov@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a8d4205623ae965e36c68629db306ca0695a2771 upstream.

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 <yehuda@inktank.com>
CC: Sage Weil <sage@inktank.com>
CC: ceph-devel@vger.kernel.org
Coverity-id: 1226882
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rbd: handle parent_overlap on writes correctly 2014-07-09T18:18:26+00:00 Ilya Dryomov ilya.dryomov@inktank.com 2014-06-10T09:53:29+00:00 caa1bc98057da9435a67aa6e508469b4b0238615 commit 9638556a276125553549fdfe349c464481ec2f39 upstream. The following check in rbd_img_obj_request_submit() rbd_dev->parent_overlap <= obj_request->img_offset allows the fall through to the non-layered write case even if both parent_overlap and obj_request->img_offset belong to the same RADOS object. This leads to data corruption, because the area to the left of parent_overlap ends up unconditionally zero-filled instead of being populated with parent data. Suppose we want to write 1M to offset 6M of image bar, which is a clone of foo@snap; object_size is 4M, parent_overlap is 5M: rbd_data.<id>.0000000000000001 ---------------------|----------------------|------------ | should be copyup'ed | should be zeroed out | write ... ---------------------|----------------------|------------ 4M 5M 6M parent_overlap obj_request->img_offset 4..5M should be copyup'ed from foo, yet it is zero-filled, just like 5..6M is. Given that the only striping mode kernel client currently supports is chunking (i.e. stripe_unit == object_size, stripe_count == 1), round parent_overlap up to the next object boundary for the purposes of the overlap check. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9638556a276125553549fdfe349c464481ec2f39 upstream.

The following check in rbd_img_obj_request_submit()

    rbd_dev->parent_overlap <= obj_request->img_offset

allows the fall through to the non-layered write case even if both
parent_overlap and obj_request->img_offset belong to the same RADOS
object.  This leads to data corruption, because the area to the left of
parent_overlap ends up unconditionally zero-filled instead of being
populated with parent data.  Suppose we want to write 1M to offset 6M
of image bar, which is a clone of foo@snap; object_size is 4M,
parent_overlap is 5M:

    rbd_data.<id>.0000000000000001
     ---------------------|----------------------|------------
    | should be copyup'ed | should be zeroed out | write ...
     ---------------------|----------------------|------------
   4M                    5M                     6M
                    parent_overlap    obj_request->img_offset

4..5M should be copyup'ed from foo, yet it is zero-filled, just like
5..6M is.

Given that the only striping mode kernel client currently supports is
chunking (i.e. stripe_unit == object_size, stripe_count == 1), round
parent_overlap up to the next object boundary for the purposes of the
overlap check.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rbd: use reference counts for image requests 2014-07-09T18:18:26+00:00 Alex Elder elder@linaro.org 2014-04-26T10:21:44+00:00 33e2582114901a0ad084a8d6f1a20e28a33243de commit 0f2d5be792b0466b06797f637cfbb0f64dbb408c upstream. Each image request contains a reference count, but to date it has not actually been used. (I think this was just an oversight.) A recent report involving rbd failing an assertion shed light on why and where we need to use these reference counts. Every OSD request associated with an object request uses rbd_osd_req_callback() as its callback function. That function will call a helper function (dependent on the type of OSD request) that will set the object request's "done" flag if the object request if appropriate. If that "done" flag is set, the object request is passed to rbd_obj_request_complete(). In rbd_obj_request_complete(), requests are processed in sequential order. So if an object request completes before one of its predecessors in the image request, the completion is deferred. Otherwise, if it's a completing object's "turn" to be completed, it is passed to rbd_img_obj_end_request(), which records the result of the operation, accumulates transferred bytes, and so on. Next, the successor to this request is checked and if it is marked "done", (deferred) completion processing is performed on that request, and so on. If the last object request in an image request is completed, rbd_img_request_complete() is called, which (typically) destroys the image request. There is a race here, however. The instant an object request is marked "done" it can be provided (by a thread handling completion of one of its predecessor operations) to rbd_img_obj_end_request(), which (for the last request) can then lead to the image request getting torn down. And this can happen *before* that object has itself entered rbd_img_obj_end_request(). As a result, once it *does* enter that function, the image request (and even the object request itself) may have been freed and become invalid. All that's necessary to avoid this is to properly count references to the image requests. We tear down an image request's object requests all at once--only when the entire image request has completed. So there's no need for an image request to count references for its object requests. However, we don't want an image request to go away until the last of its object requests has passed through rbd_img_obj_callback(). In other words, we don't want rbd_img_request_complete() to necessarily result in the image request being destroyed, because it may get called before we've finished processing on all of its object requests. So the fix is to add a reference to an image request for each of its object requests. The reference can be viewed as representing an object request that has not yet finished its call to rbd_img_obj_callback(). That is emphasized by getting the reference right after assigning that as the image object's callback function. The corresponding release of that reference is done at the end of rbd_img_obj_callback(), which every image object request passes through exactly once. Signed-off-by: Alex Elder <elder@linaro.org> Reviewed-by: Ilya Dryomov <ilya.dryomov@inktank.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0f2d5be792b0466b06797f637cfbb0f64dbb408c upstream.

Each image request contains a reference count, but to date it has
not actually been used.  (I think this was just an oversight.) A
recent report involving rbd failing an assertion shed light on why
and where we need to use these reference counts.

Every OSD request associated with an object request uses
rbd_osd_req_callback() as its callback function.  That function will
call a helper function (dependent on the type of OSD request) that
will set the object request's "done" flag if the object request if
appropriate.  If that "done" flag is set, the object request is
passed to rbd_obj_request_complete().

In rbd_obj_request_complete(), requests are processed in sequential
order.  So if an object request completes before one of its
predecessors in the image request, the completion is deferred.
Otherwise, if it's a completing object's "turn" to be completed, it
is passed to rbd_img_obj_end_request(), which records the result of
the operation, accumulates transferred bytes, and so on.  Next, the
successor to this request is checked and if it is marked "done",
(deferred) completion processing is performed on that request, and
so on.  If the last object request in an image request is completed,
rbd_img_request_complete() is called, which (typically) destroys
the image request.

There is a race here, however.  The instant an object request is
marked "done" it can be provided (by a thread handling completion of
one of its predecessor operations) to rbd_img_obj_end_request(),
which (for the last request) can then lead to the image request
getting torn down.  And this can happen *before* that object has
itself entered rbd_img_obj_end_request().  As a result, once it
*does* enter that function, the image request (and even the object
request itself) may have been freed and become invalid.

All that's necessary to avoid this is to properly count references
to the image requests.  We tear down an image request's object
requests all at once--only when the entire image request has
completed.  So there's no need for an image request to count
references for its object requests.  However, we don't want an
image request to go away until the last of its object requests
has passed through rbd_img_obj_callback().  In other words,
we don't want rbd_img_request_complete() to necessarily
result in the image request being destroyed, because it may
get called before we've finished processing on all of its
object requests.

So the fix is to add a reference to an image request for
each of its object requests.  The reference can be viewed
as representing an object request that has not yet finished
its call to rbd_img_obj_callback().  That is emphasized by
getting the reference right after assigning that as the image
object's callback function.  The corresponding release of that
reference is done at the end of rbd_img_obj_callback(), which
every image object request passes through exactly once.

Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rbd: fix error paths in rbd_img_request_fill() 2014-05-31T20:20:28+00:00 Ilya Dryomov ilya.dryomov@inktank.com 2014-03-04T09:57:17+00:00 524cf7932e479d835e5677b588b61836821e7dfe commit 42dd037c08c7cd6e3e9af7824b0c1d063f838885 upstream. Doing rbd_obj_request_put() in rbd_img_request_fill() error paths is not only insufficient, but also triggers an rbd_assert() in rbd_obj_request_destroy(): Assertion failure in rbd_obj_request_destroy() at line 1867: rbd_assert(obj_request->img_request == NULL); rbd_img_obj_request_add() adds obj_requests to the img_request, the opposite is rbd_img_obj_request_del(). Use it. Fixes: http://tracker.ceph.com/issues/7327 Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 42dd037c08c7cd6e3e9af7824b0c1d063f838885 upstream.

Doing rbd_obj_request_put() in rbd_img_request_fill() error paths is
not only insufficient, but also triggers an rbd_assert() in
rbd_obj_request_destroy():

    Assertion failure in rbd_obj_request_destroy() at line 1867:

    rbd_assert(obj_request->img_request == NULL);

rbd_img_obj_request_add() adds obj_requests to the img_request, the
opposite is rbd_img_obj_request_del().  Use it.

Fixes: http://tracker.ceph.com/issues/7327

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rbd: drop an unsafe assertion 2014-03-29T17:38:14+00:00 Alex Elder elder@linaro.org 2014-03-25T13:36:02+00:00 638c323c4d1f8eaf25224946e21ce8818f1bcee1 Olivier Bonvalet reported having repeated crashes due to a failed assertion he was hitting in rbd_img_obj_callback(): Assertion failure in rbd_img_obj_callback() at line 2165: rbd_assert(which >= img_request->next_completion); With a lot of help from Olivier with reproducing the problem we were able to determine the object and image requests had already been completed (and often freed) at the point the assertion failed. There was a great deal of discussion on the ceph-devel mailing list about this. The problem only arose when there were two (or more) object requests in an image request, and the problem was always seen when the second request was being completed. The problem is due to a race in the window between setting the "done" flag on an object request and checking the image request's next completion value. When the first object request completes, it checks to see if its successor request is marked "done", and if so, that request is also completed. In the process, the image request's next_completion value is updated to reflect that both the first and second requests are completed. By the time the second request is able to check the next_completion value, it has been set to a value *greater* than its own "which" value, which caused an assertion to fail. Fix this problem by skipping over any completion processing unless the completing object request is the next one expected. Test only for inequality (not >=), and eliminate the bad assertion. Tested-by: Olivier Bonvalet <ob@daevel.fr> Signed-off-by: Alex Elder <elder@linaro.org> Reviewed-by: Sage Weil <sage@inktank.com> Reviewed-by: Ilya Dryomov <ilya.dryomov@inktank.com> 
Olivier Bonvalet reported having repeated crashes due to a failed
assertion he was hitting in rbd_img_obj_callback():

    Assertion failure in rbd_img_obj_callback() at line 2165:
	rbd_assert(which >= img_request->next_completion);

With a lot of help from Olivier with reproducing the problem
we were able to determine the object and image requests had
already been completed (and often freed) at the point the
assertion failed.

There was a great deal of discussion on the ceph-devel mailing list
about this.  The problem only arose when there were two (or more)
object requests in an image request, and the problem was always
seen when the second request was being completed.

The problem is due to a race in the window between setting the
"done" flag on an object request and checking the image request's
next completion value.  When the first object request completes, it
checks to see if its successor request is marked "done", and if
so, that request is also completed.  In the process, the image
request's next_completion value is updated to reflect that both
the first and second requests are completed.  By the time the
second request is able to check the next_completion value, it
has been set to a value *greater* than its own "which" value,
which caused an assertion to fail.

Fix this problem by skipping over any completion processing
unless the completing object request is the next one expected.
Test only for inequality (not >=), and eliminate the bad
assertion.

Tested-by: Olivier Bonvalet <ob@daevel.fr>
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Sage Weil <sage@inktank.com>
Reviewed-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30T19:19:05+00:00 Linus Torvalds torvalds@linux-foundation.org 2014-01-30T19:19:05+00:00 f568849edac8611d603e00bd6cbbcfea09395ae6 Pull core block IO changes from Jens Axboe: "The major piece in here is the immutable bio_ve series from Kent, the rest is fairly minor. It was supposed to go in last round, but various issues pushed it to this release instead. The pull request contains: - Various smaller blk-mq fixes from different folks. Nothing major here, just minor fixes and cleanups. - Fix for a memory leak in the error path in the block ioctl code from Christian Engelmayer. - Header export fix from CaiZhiyong. - Finally the immutable biovec changes from Kent Overstreet. This enables some nice future work on making arbitrarily sized bios possible, and splitting more efficient. Related fixes to immutable bio_vecs: - dm-cache immutable fixup from Mike Snitzer. - btrfs immutable fixup from Muthu Kumar. - bio-integrity fix from Nic Bellinger, which is also going to stable" * 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits) xtensa: fixup simdisk driver to work with immutable bio_vecs block/blk-mq-cpu.c: use hotcpu_notifier() blk-mq: for_each_* macro correctness block: Fix memory leak in rw_copy_check_uvector() handling bio-integrity: Fix bio_integrity_verify segment start bug block: remove unrelated header files and export symbol blk-mq: uses page->list incorrectly blk-mq: use __smp_call_function_single directly btrfs: fix missing increment of bi_remaining Revert "block: Warn and free bio if bi_end_io is not set" block: Warn and free bio if bi_end_io is not set blk-mq: fix initializing request's start time block: blk-mq: don't export blk_mq_free_queue() block: blk-mq: make blk_sync_queue support mq block: blk-mq: support draining mq queue dm cache: increment bi_remaining when bi_end_io is restored block: fixup for generic bio chaining block: Really silence spurious compiler warnings block: Silence spurious compiler warnings block: Kill bio_pair_split() ... 
Pull core block IO changes from Jens Axboe:
 "The major piece in here is the immutable bio_ve series from Kent, the
  rest is fairly minor.  It was supposed to go in last round, but
  various issues pushed it to this release instead.  The pull request
  contains:

   - Various smaller blk-mq fixes from different folks.  Nothing major
     here, just minor fixes and cleanups.

   - Fix for a memory leak in the error path in the block ioctl code
     from Christian Engelmayer.

   - Header export fix from CaiZhiyong.

   - Finally the immutable biovec changes from Kent Overstreet.  This
     enables some nice future work on making arbitrarily sized bios
     possible, and splitting more efficient.  Related fixes to immutable
     bio_vecs:

        - dm-cache immutable fixup from Mike Snitzer.
        - btrfs immutable fixup from Muthu Kumar.

  - bio-integrity fix from Nic Bellinger, which is also going to stable"

* 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits)
  xtensa: fixup simdisk driver to work with immutable bio_vecs
  block/blk-mq-cpu.c: use hotcpu_notifier()
  blk-mq: for_each_* macro correctness
  block: Fix memory leak in rw_copy_check_uvector() handling
  bio-integrity: Fix bio_integrity_verify segment start bug
  block: remove unrelated header files and export symbol
  blk-mq: uses page->list incorrectly
  blk-mq: use __smp_call_function_single directly
  btrfs: fix missing increment of bi_remaining
  Revert "block: Warn and free bio if bi_end_io is not set"
  block: Warn and free bio if bi_end_io is not set
  blk-mq: fix initializing request's start time
  block: blk-mq: don't export blk_mq_free_queue()
  block: blk-mq: make blk_sync_queue support mq
  block: blk-mq: support draining mq queue
  dm cache: increment bi_remaining when bi_end_io is restored
  block: fixup for generic bio chaining
  block: Really silence spurious compiler warnings
  block: Silence spurious compiler warnings
  block: Kill bio_pair_split()
  ...
libceph: rename ceph_osd_request::r_{oloc,oid} to r_base_{oloc,oid} 2014-01-27T21:57:49+00:00 Ilya Dryomov ilya.dryomov@inktank.com 2014-01-27T15:40:20+00:00 3c972c95c68f455d80ff185aa440857be046bbe0 Rename ceph_osd_request::r_{oloc,oid} to r_base_{oloc,oid} before introducing r_target_{oloc,oid} needed for redirects. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com> 
Rename ceph_osd_request::r_{oloc,oid} to r_base_{oloc,oid} before
introducing r_target_{oloc,oid} needed for redirects.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: introduce and start using oid abstraction 2014-01-27T21:57:28+00:00 Ilya Dryomov ilya.dryomov@inktank.com 2014-01-27T15:40:18+00:00 4295f2217a5aa8ef2738e3a368db3c1ceab41212 In preparation for tiering support, which would require having two (base and target) object names for each osd request and also copying those names around, introduce struct ceph_object_id (oid) and a couple helpers to facilitate those copies and encapsulate the fact that object name is not necessarily a NUL-terminated string. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com> 
In preparation for tiering support, which would require having two
(base and target) object names for each osd request and also copying
those names around, introduce struct ceph_object_id (oid) and a couple
helpers to facilitate those copies and encapsulate the fact that object
name is not necessarily a NUL-terminated string.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>