Add RPC client transport switch support for replacing buffer management
 on a per-transport basis.

 In the current IPv4 socket transport implementation, RPC buffers are
 allocated as needed for each RPC message that is sent.  Some transport
 implementations may choose to use pre-allocated buffers for encoding,
 sending, receiving, and unmarshalling RPC messages, however.  For
 transports capable of direct data placement, the buffers can be carved
 out of a pre-registered area of memory rather than from a slab cache.

 Test-plan:
 Millions of fsx operations.  Performance characterization with "sio" and
 "iozone".  Use oprofile and other tools to look for significant regression
 in CPU utilization.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 This patch removes ths unused function xdr_decode_string().
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Acked-by: NNeil Brown <neilb@suse.de>
Acked-by: NCharles Lever <Charles.Lever@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 ...and make sure that the "intr" flag also enables SIGHUP and SIGTERM to
 interrupt RPC calls too (as per the Solaris implementation).
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 The NFSv4 model requires us to complete all RPC calls that might
 establish state on the server whether or not the user wants to
 interrupt it. We may also need to schedule new work (including
 new RPC calls) in order to cancel the new state.

 The asynchronous RPC model will allow us to ensure that RPC calls
 always complete, but in order to allow for "synchronous" RPC, we
 want to add the ability to wait for completion.
 The waits are, of course, interruptible.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Shrink the RPC task structure. Instead of storing separate pointers
 for task->tk_exit and task->tk_release, put them in a structure.

 Also pass the user data pointer as a parameter instead of passing it via
 task->tk_calldata. This enables us to nest callbacks.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

I submitted this one previously - svc_tcp_recvfrom currently returns
any errors to the caller, including ECONNRESET and the like.

This is something svc_recv isn't able to deal with:

	len = svsk->sk_recvfrom(rqstp);
	[...]
	if (len == 0 || len == -EAGAIN) {
		[...]
		return -EAGAIN;
	}

	[...]
	return len;

The nfsd main loop will exit when it sees an error code other than
EAGAIN.

The following patch fixes this problem

svc_recv is not equipped to deal with error codes other than EAGAIN,
and will propagate anything else (such as ECONNRESET) up to nfsd,
causing it to exit.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The hash.h hash_long function, when used on a 64 bit machine, ignores many
of the middle-order bits.  (The prime chosen it too bit-sparse).

IP addresses for clients of an NFS server are very likely to differ only in
the low-order bits.  As addresses are stored in network-byte-order, these
bits become middle-order bits in a little-endian 64bit 'long', and so do
not contribute to the hash.  Thus you can have the situation where all
clients appear on one hash chain.

So, until hash_long is fixed (or maybe forever), us a hash function that
works well on IP addresses - xor the bytes together.

Thanks to "Iozone" <capps@iozone.org> for identifying this problem.

Cc: "Iozone" <capps@iozone.org>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I noticed that some of 'struct proto_ops' used in the kernel may share
a cache line used by locks or other heavily modified data. (default
linker alignement is 32 bytes, and L1_CACHE_LINE is 64 or 128 at
least)

This patch makes sure a 'struct proto_ops' can be declared as const,
so that all cpus can share all parts of it without false sharing.

This is not mandatory : a driver can still use a read/write structure
if it needs to (and eventually a __read_mostly)

I made a global stubstitute to change all existing occurences to make
them const.

This should reduce the possibility of false sharing on SMP, and
speedup some socket system calls.
Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

 gss_create_upcall() should not error just because rpc.gssd closed the
 pipe on its end. Instead, it should requeue the pending requests and then
 retry.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 If we get something like the following,
 [  125.300636]  [<c04086e1>] schedule_timeout+0x54/0xa5
 [  125.305931]  [<c040866e>] io_schedule_timeout+0x29/0x33
 [  125.311495]  [<c02880c4>] blk_congestion_wait+0x70/0x85
 [  125.317058]  [<c014136b>] throttle_vm_writeout+0x69/0x7d
 [  125.322720]  [<c014714d>] shrink_zone+0xe0/0xfa
 [  125.327560]  [<c01471d4>] shrink_caches+0x6d/0x6f
 [  125.332581]  [<c01472a6>] try_to_free_pages+0xd0/0x1b5
 [  125.338056]  [<c013fa4b>] __alloc_pages+0x135/0x2e8
 [  125.343258]  [<c03b74ad>] tcp_sendmsg+0xaa0/0xb78
 [  125.348281]  [<c03d4666>] inet_sendmsg+0x48/0x53
 [  125.353212]  [<c0388716>] sock_sendmsg+0xb8/0xd3
 [  125.358147]  [<c0388773>] kernel_sendmsg+0x42/0x4f
 [  125.363259]  [<c038bc00>] sock_no_sendpage+0x5e/0x77
 [  125.368556]  [<c03ee7af>] xs_tcp_send_request+0x2af/0x375
 then the socket is blocked until memory is reclaimed, and no
 progress can ever be made.

 Try to access the emergency pools by using GFP_ATOMIC.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 The elements on rpci->in_upcall are tracked by the filp->private_data,
 which will ensure that they get released when the file is closed.

 The exception is if rpc_close_pipes() gets called first, since that
 sets rpci->ops to NULL.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 In __rpc_purge_upcall (net/sunrpc/rpc_pipe.c), the newer code to clean up
 the in_upcall list has a typo.
 Thanks to Vince Busam <vbusam@google.com> for spotting this!
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Being kernel-threads, nfsd servers don't get pre-empted (depending on
CONFIG).  If there is a steady stream of NFS requests that can be served
from cache, an nfsd thread may hold on to a cpu indefinitely, which isn't
very friendly.

So it is good to have a cond_resched in there (just before looking for a
new request to serve), to make sure we play nice.
Signed-off-by: NNeil Brown <neilb@suse.de>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Here is the patch that introduces the generic skb_checksum_complete
which also checks for hardware RX checksum faults.  If that happens,
it'll call netdev_rx_csum_fault which currently prints out a stack
trace with the device name.  In future it can turn off RX checksum.

I've converted every spot under net/ that does RX checksum checks to
use skb_checksum_complete or __skb_checksum_complete with the
exceptions of:

* Those places where checksums are done bit by bit.  These will call
netdev_rx_csum_fault directly.

* The following have not been completely checked/converted:

ipmr
ip_vs
netfilter
dccp

This patch is based on patches and suggestions from Stephen Hemminger
and David S. Miller.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the call to xprt_transmit() fails due to socket buffer space
exhaustion, we do not need to re-encode the RPC message when we
loop back through call_transmit.

Re-encoding can actually end up triggering the WARN_ON() in
call_decode() if we re-encode something like a read() request and
auth->au_rslack has changed.
It can also cause us to increment the RPCSEC_GSS sequence number
beyond the limits of the allowed window.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

->permission and ->lookup have a struct nameidata * argument these days to
pass down lookup intents.  Unfortunately some callers of lookup_hash don't
actually pass this one down.  For lookup_one_len() we don't have a struct
nameidata to pass down, but as this function is a library function only
used by filesystem code this is an acceptable limitation.  All other
callers should pass down the nameidata, so this patch changes the
lookup_hash interface to only take a struct nameidata argument and derives
the other two arguments to __lookup_hash from it.  All callers already have
the nameidata argument available so this is not a problem.

At the same time I'd like to deprecate the lookup_hash interface as there
are better exported interfaces for filesystem usage.  Before it can
actually be removed I need to fix up rpc_pipefs.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

From: Jesper Juhl <jesper.juhl@gmail.com>

This is the net/ part of the big kfree cleanup patch.

Remove pointless checks for NULL prior to calling kfree() in net/.
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Arnaldo Carvalho de Melo <acme@conectiva.com.br>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>

If an RPC socket is serving multiple programs, then the pg_authenticate of
the first program in the list is called, instead of pg_authenticate for the
program to be run.

This does not cause a problem with any programs in the current kernel, but
could confuse future code.

Also set pg_authenticate for nfsd_acl_program incase it ever gets used.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

 Fix some dprintk's so that NLM, NFS client, and RPC client compile
 cleanly if CONFIG_SYSCTL is disabled.

 Test plan:
 Compile kernel with CONFIG_NFS enabled and CONFIG_SYSCTL disabled.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 The sunrpc module should build properly even when CONFIG_SYSCTL is
 disabled.

 Reported by Jan-Benedict Glaw.

 Test plan:
 Compile kernel with CONFIG_NFS as a module and built-in, and CONFIG_SYSCTL
 enabled and disabled.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch rewrites various occurences of &sg[0] where sg is an array
of length one to simply sg.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch uses sg_set_buf/sg_init_one in some places where it was
duplicated.
Signed-off-by: NDavid Hardeman <david@2gen.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Greg KH <greg@kroah.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This reverts 747c5534 commit.

Convert nanoseconds to microseconds correctly.

Spotted by Steve Dickson <SteveD@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

 Remove some senseless wrappers.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Not only are the qop parameters that are passed around throughout the gssapi
 unused by any currently implemented mechanism, but there appears to be some
 doubt as to whether they will ever be used.  Let's just kill them off for now.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Add support for privacy to the krb5 rpcsec_gss mechanism.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 The code this was originally derived from processed wrap and mic tokens using
 the same functions.  This required some contortions, and more would be required
 with the addition of xdr_buf's, so it's better to separate out the two code
 paths.

 In preparation for adding privacy support, remove the last vestiges of the
 old wrap token code.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Factor out some code that will be shared by privacy crypto routines
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Add the code to the client side to handle privacy.  This is dead code until
 we actually add privacy support to krb5.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Various xdr encode routines use au_rslack to guess where the reply argument
 will end up, so we can set up the xdr_buf to recieve data into the right place
 for zero copy.

 Currently we calculate the au_rslack estimate when we check the verifier.
 Normally this only depends on the verifier size.  In the integrity case we add
 a few bytes to allow for a length and sequence number.

 It's a bit simpler to calculate only the verifier size when we check the
 verifier, and delay the full calculation till we unwrap.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 For privacy we need to allocate extra pages to hold encrypted page data when
 wrapping requests.  This allocation may fail, and we handle that case by
 waiting and retrying.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 For privacy, we need to allocate pages to store the encrypted data (passed
 in pages can't be used without the risk of corrupting data in the page cache).
 So we need a way to free that memory after the request has been transmitted.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Add support for privacy to generic gss-api code.  This is dead code until we
 have both a mechanism that supports privacy and code in the client or server
 that uses it.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>