The auth_x protocol implements support for a kerberos-like mutual
authentication infrastructure used by Ceph.  We do not simply use vanilla
kerberos because of scalability and performance issues when dealing with
a large cluster of nodes providing a single logical service.

Auth_x provides mutual authentication of client and server and protects
against replay and man in the middle attacks.  It does not encrypt
the full session over the wire, however, so data payload may still be
snooped.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Inlucde struct version in encoding. This will streamline future protocol
changes.
Signed-off-by: Sage Weil <sage@newdream.net>

Add infrastructure to allow the mon_client to periodically renew its auth
credentials.  Also add a messenger callback that will force such a renewal
if a peer rejects our authenticator.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Helpers to encrypt/decrypt AES and base64.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Helper for decoding into a ceph_buffer, and other misc decoding helpers
we will need.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

We release all the pages, even if the osd response was
different than the number of pages written. This could only
happen due to truncation that arrives the osd in
different order, for which we want the pages released anyway.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

This fixes a bug where the read/write ops arrive the osd after
a following truncation request.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

We never truncate to a smaller size without contacting the MDS.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Include a type/version in ceph_entity_addr and filepath.  Include extra
byte in filepath encoding as necessary.
Signed-off-by: Sage Weil <sage@newdream.net>

Signed-off-by: Sage Weil <sage@newdream.net>

This includes treating all the data preallocation and revokation
at the same place, not having to have a special case for
the reserved pages.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>

Now doing it in the same callback that is also responsible for
allocating the 'front' part of the message. If we get a message
that we haven't got a corresponding tid for, mark it for skipping.

Moving the mutex unlock/lock from the osd alloc_msg callback
to the calling function in the messenger.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>

Both front and middle parts of the message are now being
allocated at the ceph_alloc_msg().
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>

Previously, if the MDS request was interrupted, we would unregister the
request and ignore any reply.  This could cause the caps or other cache
state to become out of sync.  (For instance, aborting dbench and doing
rm -r on clients would complain about a non-empty directory because the
client didn't realize it's aborted file create request completed.)

Even we don't unregister, we still can't process the reply normally because
we are no longer holding the caller's locks (like the dir i_mutex).

So, mark aborted operations with r_aborted, and in the reply handler, be
sure to process all the caps.  Do not process the namespace changes,
though, since we no longer will hold the dir i_mutex.  The dentry lease
state can also be ignored as it's more forgiving.
Signed-off-by: Sage Weil <sage@newdream.net>

CEPH_MDS_OP_CREATE was not correctly marked as a write operation.
Signed-off-by: Sage Weil <sage@newdream.net>

The variable client is initialized twice to the same (side effect-free)
expression.  Drop one initialization.

A simplified version of the semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)

// <smpl>
@forall@
idexpression *x;
identifier f!=ERR_PTR;
@@

x = f(...)
... when != x
(
x = f(...,<+...x...+>,...)
|
* x = f(...)
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Sage Weil <sage@newdream.net>

Signed-off-by: Sage Weil <sage@newdream.net>

The ceph_entity_addr erank field is obsolete; remove it.  Get rid of
trivial addr comparison helpers while we're at it.
Signed-off-by: Sage Weil <sage@newdream.net>

This fixes a bug, where we had the parent list have dentries with
offsets that are not monotonically increasing, which caused the ceph
dcache_readdir to skip entries.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

The function was broken in the case where there was more than one page
involved, broke the ceph sync_write case.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Use the ceph_pagelist to encode the MDS reconnect message.  We change the
message encoding (protocol change!) at the same time to make our life
easier (we don't know how many snaprealms we have when we start encoding).

An empty message implies the session is closed/does not exist.
Signed-off-by: Sage Weil <sage@newdream.net>

The ceph_pagelist is a simple list of whole pages, strung together via
their lru list_head.  It facilitates encoding to a "buffer" of unknown
size.  Allow its use in place of the ceph_msg page vector.

This will be used to fix the huge buffer preallocation woes of MDS
reconnection.
Signed-off-by: Sage Weil <sage@newdream.net>

Define supported and required feature set.  Fail connection if the server
requires features we do not support (TAG_FEATURES), or if the server does
not support features we require.
Signed-off-by: Sage Weil <sage@newdream.net>

Many (most?) message types include a transaction id.  By including it in
the fixed size header, we always have it available even when we are unable
to allocate memory for the (larger, variable sized) message body.  This
will allow us to error out the appropriate request instead of (silently)
dropping the reply.
Signed-off-by: Sage Weil <sage@newdream.net>

Signed-off-by: Sage Weil <sage@newdream.net>

When we issue an OSD read, we specify a vector of pages that the data is to
be read into.  The request may be sent multiple times, to multiple OSDs, if
the osdmap changes, which means we can get more than one reply.

Only read data into the page vector if the reply is coming from the
OSD we last sent the request to.  Keep track of which connection is using
the vector by taking a reference.  If another connection was already
using the vector before and a new reply comes in on the right connection,
revoke the pages from the other connection.
Signed-off-by: Sage Weil <sage@newdream.net>

Use a single mutex (previously out_mutex) to protect both read and write
activity from concurrent ceph_con_* calls.  Drop the mutex when doing
callbacks to avoid nested locking (the callback may need to call something
like ceph_con_close).
Signed-off-by: Sage Weil <sage@newdream.net>

Canceled or timed out osd requests were getting left in the request list
and never deallocated (until umount).  Unregister if they are canceled
(control-c) or time out.
Signed-off-by: Sage Weil <sage@newdream.net>

Signed-off-by: Sage Weil <sage@newdream.net>

Avoid confusing iterate_session_caps(), flag the session while we are
iterating so that __touch_cap does not rearrange items on the list.

All other modifiers of session->s_caps do so under the protection of
s_mutex.
Signed-off-by: Sage Weil <sage@newdream.net>

An incremental pg_temp wasn't being decoded properly (wrong bound on
for loop).

Also remove unused local variable, while we're at it.
Signed-off-by: Sage Weil <sage@newdream.net>

Both osdmap_decode() and osdmap_apply_incremental() should never return
NULL.
Signed-off-by: Sage Weil <sage@newdream.net>

We need to hold session s_mutex for __ceph_mdsc_drop_dentry_lease(), which
we don't, so skip it.  It was purely an optimization.
Signed-off-by: Sage Weil <sage@newdream.net>

This works around a bug in vfs_rename_dir() that rehashes the target
dentry.  Ensure such dentries always fail revalidation by timing out the
dentry lease and kicking it out of the current directory lease gen.

This can be reverted when the vfs bug is fixed.
Signed-off-by: Sage Weil <sage@newdream.net>

Set bdi congestion bit when amount of write data in flight exceeds adjustable
threshold.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Fixes a deadlock that is triggered due to kswapd,
while the page was locked and the iput couldn't tear
down the address space.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>

Signed-off-by: Sage Weil <sage@newdream.net>

Signed-off-by: Sage Weil <sage@newdream.net>