We may first learn our fsid from any of the mon, osd, or mds maps
(whichever the monitor sends first).  Consolidate checks in a single
helper.  Initialize the client debugfs entry then, since we need the
fsid (and global_id) for the directory name.

Also remove dead mount code.
Signed-off-by: NSage Weil <sage@newdream.net>

When we open a monitor session, we send an initial AUTH message listing
the auth protocols we support, our entity name, and (possibly) a previously
assigned global_id.  The monitor chooses a protocol and responds with an
initial message.

Initially implement AUTH_NONE, a dummy protocol that provides no security,
but works within the new framework.  It generates 'authorizers' that are
used when connecting to (mds, osd) services that simply state our entity
name and global_id.

This is a wire protocol change.
Signed-off-by: NSage Weil <sage@newdream.net>

Unwind initializing if we get ENOMEM during client initialization.
Signed-off-by: NSage Weil <sage@newdream.net>

We want to ceph_con_close when we're done with the connection, before
the ref count reaches 0.  Once it does, do not call ceph_con_shutdown,
as that takes the con mutex and may sleep, and besides that is
unnecessary.
Signed-off-by: NSage Weil <sage@newdream.net>

The endian conversions don't quite work with the old union ceph_pg.  Just
make it a regular struct, and make each field __le.  This is simpler and it
has the added bonus of actually working.
Signed-off-by: NSage Weil <sage@newdream.net>

This simplifies much of the error handling during mount.  It also means
that we have the mount args before client creation, and we can initialize
based on those options.
Signed-off-by: NSage Weil <sage@newdream.net>

Pass the front_len we need when pulling a message off a msgpool,
and WARN if it is greater than the pool's size.  Then try to
allocate a new message (to continue without failing).
Signed-off-by: NSage Weil <sage@newdream.net>

This avoids the fugly pass by reference and makes the code a bit easier
to read.
Signed-off-by: NSage Weil <sage@newdream.net>

This ensures we don't submit the same request twice if we are kicking a
specific osd (as with an osd_reset), or when we hit a transient error and
resend.
Signed-off-by: NSage Weil <sage@newdream.net>

The peer_reset just takes longer (until we reconnect and discover the osd
dropped the session... which it will).
Signed-off-by: NSage Weil <sage@newdream.net>

If an osd has failed or returned and a request has been sent twice, it's
possible to get a reply and unregister the request while the request
message is queued for delivery.  Since the message references the caller's
page vector, we need to revoke it before completing.
Signed-off-by: NSage Weil <sage@newdream.net>

The osd request submission path registers the request, drops and retakes
the request_mutex, then sends it to the OSD.  A racing kick_requests could
sent it during that interval, causing the same msg to be sent twice and
BUGing in the msgr.

Fix by only sending the message if it hasn't been touched by other
threads.
Signed-off-by: NSage Weil <sage@newdream.net>

The OSD client is responsible for reading and writing data from/to the
object storage pool.  This includes determining where objects are
stored in the cluster, and ensuring that requests are retried or
redirected in the event of a node failure or data migration.

If an OSD does not respond before a timeout expires, keepalive
messages are sent across the lossless, ordered communications channel
to ensure that any break in the TCP is discovered.  If the session
does reset, a reconnection is attempted and affected requests are
resent (by the message transport layer).
Signed-off-by: NSage Weil <sage@newdream.net>