Commit Graph

14 Commits

Author SHA1 Message Date
John Baldwin
3b14c753ff Revert 195703 and 195821 as this special stop handling in NFS is now
implemented via VFCF_SBDRY rather than passing PBDRY to individual
sleep calls.
2013-03-13 21:06:03 +00:00
Rick Macklem
e2adc47dbb Add support for backchannels to the kernel RPC. Backchannels
are used by NFSv4.1 for callbacks. A backchannel is a connection
established by the client, but used for RPCs done by the server
on the client (callbacks). As a result, this patch mixes some
client side calls in the server side and vice versa. Some
definitions in the .c files were extracted out into a file called
krpc.h, so that they could be included in multiple .c files.
This code has been in projects/nfsv4.1-client for some time.
Although no one has given it a formal review, I believe kib@
has taken a look at it.
2012-12-08 00:29:16 +00:00
Rick Macklem
7b67bd9f3d This patch is believed to fix a problem in the kernel rpc for
non-interruptible NFS mounts, where a kernel thread will seem
to be stuck sleeping on "rpccon". The msleep() in clnt_vc_create()
that was waiting to a TCP connect to complete would return ERESTART,
since PCATCH was specified. Then the tsleep() in clnt_reconnect_call()
would sleep for 1 second and then try again and again and...
The patch changes the msleep() in clnt_vc_create() so it only sets
the PCATCH flag for interruptible cases.

Tested by:	pho
Reviewed by:	jhb
MFC after:	2 weeks
2011-04-27 18:19:26 +00:00
Marko Zec
0348c661d1 Fix NFS panics with options VIMAGE kernels by apropriately setting curvnet
context inside the RPC code.

Temporarily set td's cred to mount's cred before calling socreate() via
__rpc_nconf2socket().

Submitted by:	rmacklem (in part)
Reviewed by:	rmacklem, rwatson
Discussed with:	dfr, bz
Approved by:	re (rwatson), julian (mentor)
MFC after:	3 days
2009-08-24 10:09:30 +00:00
Konstantin Belousov
b35687df13 Use PBDRY flag for msleep(9) in NFS and NLM when sleeping thread owns
kernel resources that block other threads, like vnode locks. The SIGSTOP
sent to such thread (process, rather) shall not stop it until thread
releases the resources.

Tested by:	pho
Reviewed by:	jhb
Approved by:	re (kensmith)
2009-07-14 22:54:29 +00:00
Rick Macklem
72263475c4 Fix two known problems in clnt_rc.c, plus issues w.r.t. smp noted
during reading of the code. Change the code so that it never accesses
rc_connecting, rc_closed or rc_client when the rc_lock mutex is not held.
Also, it now performs the CLNT_CLOSE(client) and CLNT_RELEASE(client)
calls after the rc_lock mutex has been released, since those calls do
msleep()s with another mutex held. Change clnt_reconnect_call() so that
releasing the reference count is delayed until after the
"if (rc->rc_client == client)" check, so that rc_client cannot have been
recycled.

Tested by:	pho
Reviewed by:	dfr
Approved by:	kib (mentor)
2009-06-25 00:28:43 +00:00
Rick Macklem
dce35fe0ff For the case where another thread was doing a connect and that
connect failed, the thread would be left stuck in msleep()
indefinitely, since it would call msleep() again for the case
where rc_client == NULL. Change the loop criteria and the if just
after the loop, so that this case is handled correctly.

Reviewed by:	dfr
Approved by:	kib (mentor)
2009-06-10 19:02:09 +00:00
Doug Rabson
9719301922 Use the correct creds when reconnecting so that we have enough privilege to
bind reserved ports (if necessary).

Submitted by:	Jaakko Heinonen <jh at saualaht dot fi>
2009-02-05 11:48:10 +00:00
Doug Rabson
a9148abd9d Implement support for RPCSEC_GSS authentication to both the NFS client
and server. This replaces the RPC implementation of the NFS client and
server with the newer RPC implementation originally developed
(actually ported from the userland sunrpc code) to support the NFS
Lock Manager.  I have tested this code extensively and I believe it is
stable and that performance is at least equal to the legacy RPC
implementation.

The NFS code currently contains support for both the new RPC
implementation and the older legacy implementation inherited from the
original NFS codebase. The default is to use the new implementation -
add the NFS_LEGACYRPC option to fall back to the old code. When I
merge this support back to RELENG_7, I will probably change this so
that users have to 'opt in' to get the new code.

To use RPCSEC_GSS on either client or server, you must build a kernel
which includes the KGSSAPI option and the crypto device. On the
userland side, you must build at least a new libc, mountd, mount_nfs
and gssd. You must install new versions of /etc/rc.d/gssd and
/etc/rc.d/nfsd and add 'gssd_enable=YES' to /etc/rc.conf.

As long as gssd is running, you should be able to mount an NFS
filesystem from a server that requires RPCSEC_GSS authentication. The
mount itself can happen without any kerberos credentials but all
access to the filesystem will be denied unless the accessing user has
a valid ticket file in the standard place (/tmp/krb5cc_<uid>). There
is currently no support for situations where the ticket file is in a
different place, such as when the user logged in via SSH and has
delegated credentials from that login. This restriction is also
present in Solaris and Linux. In theory, we could improve this in
future, possibly using Brooks Davis' implementation of variant
symlinks.

Supporting RPCSEC_GSS on a server is nearly as simple. You must create
service creds for the server in the form 'nfs/<fqdn>@<REALM>' and
install them in /etc/krb5.keytab. The standard heimdal utility ktutil
makes this fairly easy. After the service creds have been created, you
can add a '-sec=krb5' option to /etc/exports and restart both mountd
and nfsd.

The only other difference an administrator should notice is that nfsd
doesn't fork to create service threads any more. In normal operation,
there will be two nfsd processes, one in userland waiting for TCP
connections and one in the kernel handling requests. The latter
process will create as many kthreads as required - these should be
visible via 'top -H'. The code has some support for varying the number
of service threads according to load but initially at least, nfsd uses
a fixed number of threads according to the value supplied to its '-n'
option.

Sponsored by:	Isilon Systems
MFC after:	1 month
2008-11-03 10:38:00 +00:00
Doug Rabson
8082cff418 Add a missing call to mtx_destroy() in clnt_reconnect_destroy().
Submitted by:	zachary.loafman at isilon.com
MFC after:	2 weeks
2008-08-13 12:04:54 +00:00
Doug Rabson
c675522fc4 Re-implement the client side of rpc.lockd in the kernel. This implementation
provides the correct semantics for flock(2) style locks which are used by the
lockf(1) command line tool and the pidfile(3) library. It also implements
recovery from server restarts and ensures that dirty cache blocks are written
to the server before obtaining locks (allowing multiple clients to use file
locking to safely share data).

Sponsored by:	Isilon Systems
PR:		94256
MFC after:	2 weeks
2008-06-26 10:21:54 +00:00
Doug Rabson
8d9278ba1c Fix some issues that showed up during Kris' testing.
Reported by:	kris
MFC after:	3 days
2008-04-11 10:34:59 +00:00
Doug Rabson
ee31b83a3a Minor changes to improve compatibility with older FreeBSD releases. 2008-03-28 09:50:32 +00:00
Doug Rabson
dfdcada31e Add the new kernel-mode NFS Lock Manager. To use it instead of the
user-mode lock manager, build a kernel with the NFSLOCKD option and
add '-k' to 'rpc_lockd_flags' in rc.conf.

Highlights include:

* Thread-safe kernel RPC client - many threads can use the same RPC
  client handle safely with replies being de-multiplexed at the socket
  upcall (typically driven directly by the NIC interrupt) and handed
  off to whichever thread matches the reply. For UDP sockets, many RPC
  clients can share the same socket. This allows the use of a single
  privileged UDP port number to talk to an arbitrary number of remote
  hosts.

* Single-threaded kernel RPC server. Adding support for multi-threaded
  server would be relatively straightforward and would follow
  approximately the Solaris KPI. A single thread should be sufficient
  for the NLM since it should rarely block in normal operation.

* Kernel mode NLM server supporting cancel requests and granted
  callbacks. I've tested the NLM server reasonably extensively - it
  passes both my own tests and the NFS Connectathon locking tests
  running on Solaris, Mac OS X and Ubuntu Linux.

* Userland NLM client supported. While the NLM server doesn't have
  support for the local NFS client's locking needs, it does have to
  field async replies and granted callbacks from remote NLMs that the
  local client has contacted. We relay these replies to the userland
  rpc.lockd over a local domain RPC socket.

* Robust deadlock detection for the local lock manager. In particular
  it will detect deadlocks caused by a lock request that covers more
  than one blocking request. As required by the NLM protocol, all
  deadlock detection happens synchronously - a user is guaranteed that
  if a lock request isn't rejected immediately, the lock will
  eventually be granted. The old system allowed for a 'deferred
  deadlock' condition where a blocked lock request could wake up and
  find that some other deadlock-causing lock owner had beaten them to
  the lock.

* Since both local and remote locks are managed by the same kernel
  locking code, local and remote processes can safely use file locks
  for mutual exclusion. Local processes have no fairness advantage
  compared to remote processes when contending to lock a region that
  has just been unlocked - the local lock manager enforces a strict
  first-come first-served model for both local and remote lockers.

Sponsored by:	Isilon Systems
PR:		95247 107555 115524 116679
MFC after:	2 weeks
2008-03-26 15:23:12 +00:00