mds: document EXCL -> (MIX or SYNC) transition decision

Previously (in w26f6a8e48ae575f17c850e28e969d55bceefbc0f), for reasons that
are somewhat obscured by passage of time, we did

+      if ((other_wanted & (CEPH_CAP_GRD|CEPH_CAP_GWR)) ||

But then we noticed that the loner may want to RD/WR and we are losing the
loner status for some other reason.  So just recently in
b48dfeba3f99451815a5e2a538bea15cd87220d2 we changed it to

+      if (((other_wanted|loner_wanted) & (CEPH_CAP_GRD|CEPH_CAP_GWR)) ||

Then we noticed that a non-loner wanting to read and a loner wanting to
read (i.e., no writers!) would lead to MIX, even when we want SYNC.
So in 07b36992da35e8b54acf76af6c893a0d86f048fb we changed to

+      if (((other_wanted|loner_wanted) & CEPH_CAP_GWR) ||

This appears to be correct.  The possible choices (wrt caps wanted):

loner  other   want
R      R       SYNC
R      R|W     MIX
R      W       MIX
R|W    R       MIX
R|W    R|W     MIX
R|W    W       MIX
W      R       MIX
W      R|W     MIX
W      W       MIX

Which means any writer -> we want MIX.  We only want SYNC when there is
nobody who wants to write.  Because you can't write in SYNC.  Which in
retrospect seems obvious.

Signed-off-by: Sage Weil <sage@inktank.com>
rgw_op: enforce minimum part size in multi-part uploads

Signed-off-by: caleb miles <caleb.miles@inktank.com>
crush-map.rst: add info about multiple crush heirarchies

Signed-off-by: Samuel Just <sam.just@inktank.com>
doc: correct meaning of 'pool' in crush

This was recently made less confusing by renaming the default crush
'pool' type to 'root'. Use this terminology everywhere as well.
This was not in argonaut, so perhaps this should delay being merged.

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>

Conflicts:

	doc/rados/operations/add-or-rm-osds.rst
	doc/rados/operations/crush-map.rst
doc: draft bobtail release notes

Signed-off-by: Sage Weil <sage@inktank.com>
Merge remote-tracking branch 'gh/next'
doc: fix typo in config file

The option is host, not hostname

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
doc/release-notes: 'mon max pool pg num'

Signed-off-by: Sage Weil <sage@inktank.com>
doc/release-notes: don't use format 2 rbd images until after osds upgrade

Signed-off-by: Sage Weil <sage@inktank.com>
osd: debug EMSGSIZE / OSD_WRITETOOBIG

Signed-off-by: Sage Weil <sage@inktank.com>
rgw: configurable exit timeout

Fixes: #3638

rgw exit timeout secs : number of seconds to wait for process
to exit cleanly before forcing exit. If set to 0, it'l wait
indefinitely.

Signed-off-by: Yehuda Sadeh <yehuda@inktank.com>
doc: Added javascript code block tag.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>
doc: Added authentication and mkcephfs settings for Bobtail.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>
doc: Updated CephFS Quick Start for Bobtail.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>
doc: Updated Block Device Quick Start for Bobtail.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>
doc: Updated the 5-minute Quick Start for Bobtail.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>
doc: Added REST Gateway link to 5-minute Quick Start.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>
Updated Getting Started index to include Gateway Quick Start.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>
doc: Added Gateway Quick Start configuration file.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>
doc: Added Gateway Quick Start.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>