libceph: start using oloc abstraction

Instead of relying on pool fields in ceph_file_layout (for mapping) and
ceph_pg (for enconding), start using ceph_object_locator (oloc)
abstraction.  Note that userspace oloc currently consists of pool, key,
nspace and hash fields, while this one contains only a pool.  This is
OK, because at this point we only send (i.e. encode) olocs and never
have to receive (i.e. decode) them.

This makes keeping a copy of ceph_file_layout in every osd request
unnecessary, so ceph_osd_request::r_file_layout field is nuked.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: move ceph_file_layout helpers to ceph_fs.h

Move ceph_file_layout helper macros and inline functions to ceph_fs.h.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: rename MAX_OBJ_NAME_SIZE to CEPH_MAX_OID_NAME_LEN

In preparation for adding oid abstraction, rename MAX_OBJ_NAME_SIZE to
CEPH_MAX_OID_NAME_LEN.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: introduce and start using oid abstraction

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>
libceph: replace ceph_calc_ceph_pg() with ceph_oloc_oid_to_pg()

Switch ceph_calc_ceph_pg() to new oloc and oid abstractions and rename
it to ceph_oloc_oid_to_pg() to make its purpose more clear.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: CEPH_OSD_FLAG_* enum update

Update CEPH_OSD_FLAG_* enum.  (We need CEPH_OSD_FLAG_IGNORE_OVERLAY to
support tiering).

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: add ceph_pg_pool_by_id()

"Lookup pool info by ID" function is hidden in osdmap.c.  Expose it to
the rest of libceph.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: follow {read,write}_tier fields on osd request submission

Overwrite ceph_osd_request::r_oloc.pool with read_tier for read ops and
write_tier for write and read+write ops (aka basic tiering support).
{read,write}_tier are part of pg_pool_t since v9.  This commit bumps
our pg_pool_t decode compat version from v7 to v9, all new fields
except for {read,write}_tier are ignored.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: rename ceph_osd_request::r_{oloc,oid} to r_base_{oloc,oid}

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: follow redirect replies from osds

Follow redirect replies from osds, for details see ceph.git commit
fbbe3ad1220799b7bb00ea30fce581c5eadaf034.

v1 (current) version of redirect reply consists of oloc and oid, which
expands to pool, key, nspace, hash and oid.  However, server-side code
that would populate anything other than pool doesn't exist yet, and
hence this commit adds support for pool redirects only.  To make sure
that future server-side updates don't break us, we decode all fields
and, if any of key, nspace, hash or oid have a non-default value, error
out with "corrupt osd_op_reply ..." message.

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

Announce our (limited, see previous commit) support for CACHEPOOL
feature.

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