Allow RPC client transport implementations to be loaded as needed, or
as they become available from distributors or third-party vendors.

Note that we leave the IP sockets implementation in sunrpc.o
permanently, as IP functionality is always available in any
kernel that runs NFS.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

To allow transport capabilities to be loaded dynamically, provide an API
for registering and unregistering the transports with the RPC client.
Eventually xprt_create_transport() will be changed to search the list of
registered transports when initializing a fresh transport.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

SUNRPC: add EXPORT_SYMBOL_GPL for generic transport functions

As a preface to allowing arbitrary transport modules to be loaded
dynamically, add EXPORT_SYMBOL_GPL for all generic transport functions
that a transport implementation might want to use.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Adds a flag word to the xdrbuf struct which indicates any bulk
disposition of the data. This enables RPC transport providers to
marshal it efficiently/appropriately, and may enable other
optimizations.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The previous patch introduced a bug when copying the server address.

Also clarify a copy into the auth_flavours array: currently the two
size calculations are equivalent, but we may decide to change the size
of auth_flavors[] at some point.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The user-visible nfs4_mount_data does not contain sufficient data to
describe new mount options, and also is now a legacy structure. Replace
it with the internal nfs_parsed_mount_data for nfsv4 in-kernel use.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The user-visible nfs_mount_data does not contain sufficient data to
describe new mount options, and also is now a legacy structure. Replace
it with the internal nfs_parsed_mount_data for nfsv[23] in-kernel use.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

In preparation for rearranging the nfs mount argument passing, make the
nfs_parsed_mount_data struct visible across nfs kernel files.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The rpcbind (v3+) netid is provided by each RPC client transport. This fixes
an omission in IPv6 rpcbind client support, and enables future extension.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Move the TCP/UDP rpcbind netid's from the rpcbind client to a global header.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Due to recent edict to remove or replace printk's that can flood the system
log.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Due to recent edict to remove or replace printk's that might flood the
system log.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Due to recent edict to replace or remove printk's that can be triggered en
masse by remote misbehavior.  Left a few that only occur just before a BUG.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

I got the 'mounthost=' option wrong - it shouldn't look for an address
value, but rather a hostname value.  However, the in-kernel mount client
and NFS client cannot resolve a hostname by themselves; they rely on
user-land to pass in the resolved address.

Create a new mount option that does take an address so that the mount
program's address can be passed in.  The mount hostname is now ignored
by the kernel.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

If no mount server port number is specified, the previous change to the
kernel mount client inadvertently allows the NFS server's port number to be
the used as the mount server's port number. If the user specifies an NFS
server port (-o port=x), the mount will fail.

The fix below sets the mount server's port to 0 if no mount server
port is specified by the user.
Signed-off-by: James Lentini <jlentini@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Simplify the in-kernel mount client by using autobind instead of an
explicit call to rpc_getport_sync.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The purpose of an RPC ping (a NULL request) is to determine whether the
remote end is operating and supports the RPC program and version of the
request.

If we do an RPC bind and the remote's rpcbind service says "this
program or service isn't supported" then we have our answer already,
and we should give up immediately.

This is good for the kernel mount client, as it will cause the request
to fail, and then allow an immediate retry with different options.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Add more new error code processing to the kernel's rpcbind client
and to call_bind_status() to distinguish two cases:

Case 1: the remote has replied that the program/version tuple is not
registered (returns EACCES)

Case 2: retry with a lesser rpcbind version (rpcb now returns EPFNOSUPPORT)

This change allows more specific error processing for each of these two
cases.  We now fail case 2 instead of retrying... it's a server
configuration error not to support even rpcbind version 2.  And don't
expose this new error code to user land -- convert it to EIO before
failing the RPC.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Add new error code processing to the kernel's rpcbind client and to
call_bind_status() to distinguish two cases:

Case 1: the remote has replied that the program/version tuple is not
registered (returns -EACCES)

Case 2: another process is already in the middle of binding on this
transport (now returns -EAGAIN)

This change allows more specific retry processing for each of these two
cases.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

When a server returns a bad rpcbind reply, make rpcbind client recovery logic
retry with an older protocol version.  Older versions are more likely to work
correctly.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Add better sanity checking of server replies to the GETVERSADDR reply
decoder.  Change the error return code: EIO is what other XDR decoding
routines return if there is a failure while decoding.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

/home/cel/linux/net/sunrpc/clnt.c: In function ‘rpc_show_tasks’:
/home/cel/linux/net/sunrpc/clnt.c:1538: warning:
	signed and unsigned type in conditional expression

This points out another case where a conditional expression returns a
signed value in one arm and an unsigned value in the other.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Check the length of the passed-in server name before trying to print it in
the log.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Noticed by Tom Talpey <tmt@netapp.com>:

OBTW, there's a nit on that memcpy, too. The r_addr is an array, so

memcpy(&map->r_addr

is passing the address of the array as a char **. It's the same as
map->r_addr, but technically the wrong type.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

/home/cel/linux/net/sunrpc/clnt.c: In function ‘rpc_bind_new_program’:
/home/cel/linux/net/sunrpc/clnt.c:445: warning:
	comparison between signed and unsigned

RPC version numbers are u32, not int.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Remove one of two identical dprintk's that occur when an RPC client is
created.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Fix some problems with rpcbind v3 and v4 queries from the in-kernel rpcbind
client:

1.  The r_addr argument must be a full universal address, not just an IP
address, and

2.  The universal address in r_addr is the address of the remote rpcbind
server, not the RPC service being requested

This addresses bugzilla.kernel.org report 8891 for 2.6.23-rc and greater.

In addition, if the rpcbind client is unable to start the rpcbind request,
make sure not to leak the xprt.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

"Universal addresses" are a string representation of an IP address and
port.  They are described fully in RFC 3530, section 2.2.  Add support
for generating them in the RPC client's socket transport module.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Finalize support for setting up RPC client transports to remote RPC
services addressed via IPv6.

Based on work done by Gilles Quillard at Bull Open Source.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Clone separate connect worker functions for connecting AF_INET6 sockets.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Prepare for introduction of IPv6 versions of same.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Finishing a socket connect is the same for IPv4 and IPv6, so split it out
into a helper.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Clone xs_bindresvport into two functions, one that can handle IPv4
addresses, and one that can handle IPv6 addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Prepare for introduction of IPv6-specific socket bind function.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

We could clone xs_set_port, but this is easier overall.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Prepare for adding IPv6 support to the RPC client by adding IPv6
capabilities to rpcbind.  Note that this is support on the query side
only; registering IPv6 addresses with the local portmapper will come
later.

Note we have to take care not to fall back to using version 2 of the
rpcbind protocol if we're dealing with IPv6 address.  Version 2 doesn't
support IPv6 at all.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Clone xs_format_ipv4_peer_addresses into an IPv6 version.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Prepare to add an IPv6 version of xs_format_peer_addresses by renaming it
to xs_format_ipv4_peer_addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>