Make better use of inode* dereferencing macros to hide dereferencing chains
(including NFS_PROTO and NFS_CLIENT).
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add some extra const qualifiers into NFS.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Generalise the nfs_client structure by:

 (1) Moving nfs_client to a more general place (nfs_fs_sb.h).

 (2) Renaming its maintenance routines to be non-NFS4 specific.

 (3) Move those maintenance routines to a new non-NFS4 specific file (client.c)
     and move the declarations to internal.h.

 (4) Make nfs_find/get_client() take a full sockaddr_in to include the port
     number (will be required for NFS2/3).

 (5) Make nfs_find/get_client() take the NFS protocol version (again will be
     required to differentiate NFS2, 3 & 4 client records).

Also:

 (6) Make nfs_client construction proceed akin to inodes, marking them as under
     construction and providing a function to indicate completion.

 (7) Make nfs_get_client() wait interruptibly if it finds a client that it can
     share, but that client is currently being constructed.

 (8) Make nfs4_create_client() use (6) and (7) instead of locking cl_sem.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add a set_capabilities NFS RPC op so that the server capabilities can be set.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add a lookup filehandle NFS RPC op so that a file handle can be looked up
without requiring dentries and inodes and other VFS stuff when doing an NFS4
pathwalk during mounting.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Rename nfs_server::nfs4_state to nfs_client as it will be used to represent the
client state for NFS2 and NFS3 also.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Rename struct nfs4_client to struct nfs_client so that it can become the basis
for a general client record for NFS2 and NFS3 in addition to NFS4.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

This is needed in order to handle any NFS4ERR_DELAY errors that might be
returned by the server. It also ensures that we map the NFSv4 errors before
they are returned to userland.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 71c12b3f0abc7501f6ed231a6d17bc9c05a238dc commit)

Use FL_ACCESS flag to test and/or wait for local locks before we try
requesting a lock from the server
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Use the new behaviour of {flock,posix}_file_lock(F_UNLCK) to determine if
we held a lock, and only send the RPC request to the server if this was the
case.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

As fs/nfs/inode.c is rather large, heterogenous and unwieldy, the attached
patch splits it up into a number of files:

 (*) fs/nfs/inode.c

     Strictly inode specific functions.

 (*) fs/nfs/super.c

     Superblock management functions for NFS and NFS4, normal access, clones
     and referrals.  The NFS4 superblock functions _could_ move out into a
     separate conditionally compiled file, but it's probably not worth it as
     there're so many common bits.

 (*) fs/nfs/namespace.c

     Some namespace-specific functions have been moved here.

 (*) fs/nfs/nfs4namespace.c

     NFS4-specific namespace functions (this could be merged into the previous
     file).  This file is conditionally compiled.

 (*) fs/nfs/internal.h

     Inter-file declarations, plus a few simple utility functions moved from
     fs/nfs/inode.c.

     Additionally, all the in-.c-file externs have been moved here, and those
     files they were moved from now includes this file.

For the most part, the functions have not been changed, only some multiplexor
functions have changed significantly.

I've also:

 (*) Added some extra banner comments above some functions.

 (*) Rearranged the function order within the files to be more logical and
     better grouped (IMO), though someone may prefer a different order.

 (*) Reduced the number of #ifdefs in .c files.

 (*) Added missing __init and __exit directives.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>

Respond to a moved error on NFS lookup by setting up the referral.
Note: We don't actually follow the referral during lookup/getattr, but
later when we detect fsid mismatch in inode revalidation (similar to the
processing done for cloning submounts). Referrals will have fake attributes
until they are actually followed or traversed.
Signed-off-by: NManoj Naik <manoj@almaden.ibm.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This is (similar to getattr bitmap) but includes fs_locations and
mounted_on_fileid attributes. Use this bitmap for encoding in fs_locations
requests.
Note: We can probably do better by requesting locations as part of fsinfo
itself.
Signed-off-by: NManoj Naik <manoj@almaden.ibm.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Per referral draft, only fs_locations, fsid, and mounted_on_fileid can be
requested in a GETATTR on referrals.
Signed-off-by: NManoj Naik <manoj@almaden.ibm.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Use component4-style formats for decoding list of servers and pathnames in
fs_locations.
Signed-off-by: NManoj Naik <manoj@almaden.ibm.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

NFSv4 allows for the fact that filesystems may be replicated across
several servers or that they may be migrated to a backup server in case of
failure of the primary server.
fs_locations is an NFSv4 operation for retrieving information about the
location of migrated and/or replicated filesystems.

Based on an initial implementation by Jiaying Zhang <jiayingz@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Whenever the directory changes, we want to make sure that we always
invalidate its page cache. Fix up update_changeattr() and
nfs_mark_for_revalidate() so that they do so.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

If the call to nfs_intent_set_file() fails to open a file in
nfs4_proc_create(), we should return an error.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Thanks to Frank Filz for pointing out that we list system.nfs4_acl extended
attribute even on filesystems where we don't actually support nfs4_acl.
This is inconsistent with the e.g. ext3 POSIX ACL behaviour, and seems to
annoy cp.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Currently this will not happen if we exit before rpc_new_task() was called.
Also fix up rpc_run_task() to do the same (for consistency).
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Currently it returns NULL, which usually gets interpreted as ENOMEM. In
fact it can mean a host of issues.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

In the case where we hold a delegation stateid, use that in for inside
SETATTR calls.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Same callback hierarchy inversion as for the NFS write calls. This patch is
not strictly speaking needed by the O_DIRECT code, but avoids confusing
differences between the asynchronous read and write code.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch inverts the callback hierarchy for NFS write calls.

Instead of having the NFSv2/v3/v4-specific code set up the RPC callback
ops, we allow the original caller to do so. This allows for more
flexibility w.r.t. how to set up and tear down the nfs_write_data
structure while still allowing the NFSv3/v4 code to perform error
handling.

The greater flexibility is needed by the asynchronous O_DIRECT code, which
wants to be able to hold on to the original nfs_write_data structures after
the WRITE RPC call has completed in order to be able to replay them if the
COMMIT call determines that the server has rebooted.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Make an inode or an nfs_server struct available in the logic that handles
JUKEBOX/DELAY type errors so the NFS client can account for them.

This patch is split out from the main nfs iostat patch to highlight minor
architectural changes required to support this statistic.

Test plan:
None.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

nfs4_open_revalidate: 'res' may be used uninitialized
nfs4_callback_compound: ‘hdr_res.nops’ may be used uninitialized
			'op_nr’ may be used uninitialized
encode_getattr_res: ‘savep’ may be used uninitialized
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

My previous "const static" vs "static const" cleanup missed a single case,
patch below takes care of it.
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

It turns out that nfs4_proc_get_root() may return raw NFSv4 errors instead of
mapping them to kernel errors.  Problem spotted by Neil Horman
<nhorman@tuxdriver.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

 Upon return of a write delegation, the server will almost always bump the
 change attribute. Ensure that we pick up that change so that we don't
 invalidate our data cache unnecessarily.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Use a cred from the nfs4_client->cl_state_owners list.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 In RFC3530, the RENEW operation is allowed to use either

 the same principal, RPC security flavour and (if RPCSEC_GSS), the same
  mechanism and service that was used for SETCLIENTID_CONFIRM

 OR

 Any principal, RPC security flavour and service combination that
 currently has an OPEN file on the server.

 Choose the latter since that doesn't require us to keep credentials for
 the same principal for the entire duration of the mount.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

 Use wait_on_bit() when waiting for state recovery to complete.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Cut down on the number of unnecessary RENEW requests on the wire.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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