NFS: remove unused variable nfs_rpcstat

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

nfs: make the rpc_stat per net namespace

Now that we're exposing the rpc stats on a per-network namespace basis,
move this struct into struct nfs_net and use that to make sure only the
per-network namespace stats are exposed.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

nfs: fix UAF on pathwalk running into umount

NFS ->d_revalidate(), ->permission() and ->get_link() need to access
some parts of nfs_server when called in RCU mode:
server->flags
server->caps
*(server->io_stats)
and, worst of all, call
server->nfs_client->rpc_ops->have_delegation
(the last one - as NFS_PROTO(inode)->have_delegation()). We really
don't want to RCU-delay the entire nfs_free_server() (it would have
to be done with schedule_work() from RCU callback, since it can't
be made to run from interrupt context), but actual freeing of
nfs_server and ->io_stats can be done via call_rcu() just fine.
nfs_client part is handled simply by making nfs_free_client() use
kfree_rcu().

Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

NFS/pNFS: Set the connect timeout for the pNFS flexfiles driver

Ensure that the connect timeout for the pNFS flexfiles driver is of the
same order as the I/O timeout, so that we can fail over quickly when
trying to read from a data server that is down.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Don't cleanup sysfs superblock entry if uninitialized

Its possible to end up in nfs_free_server() before the server's superblock
sysfs entry has been initialized, in which case calling kobject_put() will
emit a WARNING. Check if the kobject has been initialized before cleaning
it up.

Fixes: 1c7251187dc0 ("NFS: add superblock sysfs entries")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: add a sysfs link to the lockd rpc_client

After lockd is started, add a symlink for lockd's rpc_client under
NFS' superblock sysfs.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Add sysfs links to sunrpc clients for nfs_clients

For the general and state management nfs_client under each mount, create
symlinks to their respective rpc_client sysfs entries.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: add superblock sysfs entries

Create a sysfs directory for each mount that corresponds to the mount's
nfs_server struct. As the mount is being constructed, use the name
"server-n", but rename it to the "MAJOR:MINOR" of the mount after assigning
a device_id. The rename approach allows us to populate the mount's directory
with links to the various rpc_client objects during the mount's
construction. The naming convention (MAJOR:MINOR) can be used to reference
a particular NFS mount's sysfs tree.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Add an "xprtsec=" NFS mount option

After some discussion, we decided that controlling transport layer
security policy should be separate from the setting for the user
authentication flavor. To accomplish this, add a new NFS mount
option to select a transport layer security policy for RPC
operations associated with the mount point.

xprtsec=none - Transport layer security is forced off.

xprtsec=tls - Establish an encryption-only TLS session. If
the initial handshake fails, the mount fails.
If TLS is not available on a reconnect, drop
the connection and try again.

xprtsec=mtls - Both sides authenticate and an encrypted
session is created. If the initial handshake
fails, the mount fails. If TLS is not available
on a reconnect, drop the connection and try
again.

To support client peer authentication (mtls), the handshake daemon
will have configurable default authentication material (certificate
or pre-shared key). In the future, mount options can be added that
can provide this material on a per-mount basis.

Updates to mount.nfs (to support xprtsec=auto) and nfs(5) will be
sent under separate cover.

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

NFS: Have struct nfs_client carry a TLS policy field

The new field is used to match struct nfs_clients that have the same
TLS policy setting.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Avoid memcpy() run-time warning for struct sockaddr overflows

The 'nfs_server' and 'mount_server' structures include a union of
'struct sockaddr' (with the older 16 bytes max address size) and
'struct sockaddr_storage' which is large enough to hold all the
supported sa_family types (128 bytes max size). The runtime memcpy()
buffer overflow checker is seeing attempts to write beyond the 16
bytes as an overflow, but the actual expected size is that of 'struct
sockaddr_storage'. Plumb the use of 'struct sockaddr_storage' more
completely through-out NFS, which results in adjusting the memcpy()
buffers to the correct union members. Avoids this false positive run-time
warning under CONFIG_FORTIFY_SOURCE:

memcpy: detected field-spanning write (size 28) of single field "&ctx->nfs_server.address" at fs/nfs/namespace.c:178 (size 16)

Reported-by: kernel test robot <yujie.liu@intel.com>
Link: https://lore.kernel.org/all/202210110948.26b43120-yujie.liu@intel.com
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Allow setting rsize / wsize to a multiple of PAGE_SIZE

Previously, we required this to value to be a power of 2 for UDP related
reasons. This patch keeps the power of 2 rule for UDP but allows more
flexibility for TCP and RDMA.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.1 provide mount option to toggle trunking discovery

Introduce a new mount option -- trunkdiscovery,notrunkdiscovery -- to
toggle whether or not the client will engage in actively discovery
of trunking locations.

v2 make notrunkdiscovery default

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Fixes: 1976b2b31462 ("NFSv4.1 query for fs_location attr on a new file system")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Fix initialisation of nfs_client cl_flags field

For some long forgotten reason, the nfs_client cl_flags field is
initialised in nfs_get_client() instead of being initialised at
allocation time. This quirk was harmless until we moved the call to
nfs_create_rpc_client().

Fixes: dd99e9f98fbf ("NFSv4: Initialise connection to the server in nfs4_alloc_client()")
Cc: stable@vger.kernel.org # 4.8.x
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4.1 query for fs_location attr on a new file system

Query the server for other possible trunkable locations for a given
file system on a 4.1+ mount.

v2:
-- added missing static to nfs4_discover_trunking,
reported by the kernel test robot

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

nfs: Convert to new fscache volume/cookie API

Change the nfs filesystem to support fscache's indexing rewrite and
reenable caching in nfs.

The following changes have been made:

(1) The fscache_netfs struct is no more, and there's no need to register
the filesystem as a whole.

(2) The session cookie is now an fscache_volume cookie, allocated with
fscache_acquire_volume(). That takes three parameters: a string
representing the "volume" in the index, a string naming the cache to
use (or NULL) and a u64 that conveys coherency metadata for the
volume.

For nfs, I've made it render the volume name string as:

"nfs,<ver>,<family>,<address>,<port>,<fsidH>,<fsidL>*<,param>[,<uniq>]"

(3) The fscache_cookie_def is no more and needed information is passed
directly to fscache_acquire_cookie(). The cache no longer calls back
into the filesystem, but rather metadata changes are indicated at
other times.

fscache_acquire_cookie() is passed the same keying and coherency
information as before.

(4) fscache_enable/disable_cookie() have been removed.

Call fscache_use_cookie() and fscache_unuse_cookie() when a file is
opened or closed to prevent a cache file from being culled and to keep
resources to hand that are needed to do I/O.

If a file is opened for writing, we invalidate it with
FSCACHE_INVAL_DIO_WRITE in lieu of doing writeback to the cache,
thereby making it cease caching until all currently open files are
closed. This should give the same behaviour as the uptream code.
Making the cache store local modifications isn't straightforward for
NFS, so that's left for future patches.

(5) fscache_invalidate() now needs to be given uptodate auxiliary data and
a file size. It also takes a flag to indicate if this was due to a
DIO write.

(6) Call nfs_fscache_invalidate() with FSCACHE_INVAL_DIO_WRITE on a file
to which a DIO write is made.

(7) Call fscache_note_page_release() from nfs_release_page().

(8) Use a killable wait in nfs_vm_page_mkwrite() when waiting for
PG_fscache to be cleared.

(9) The functions to read and write data to/from the cache are stubbed out
pending a conversion to use netfslib.

Changes
=======
ver #3:
- Added missing =n fallback for nfs_fscache_release_file()[1][2].

ver #2:
- Use gfpflags_allow_blocking() rather than using flag directly.
- fscache_acquire_volume() now returns errors.
- Remove NFS_INO_FSCACHE as it's no longer used.
- Need to unuse a cookie on file-release, not inode-clear.

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Co-developed-by: David Howells <dhowells@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
cc: Trond Myklebust <trond.myklebust@hammerspace.com>
cc: Anna Schumaker <anna.schumaker@netapp.com>
cc: linux-nfs@vger.kernel.org
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/202112100804.nksO8K4u-lkp@intel.com/ [1]
Link: https://lore.kernel.org/r/202112100957.2oEDT20W-lkp@intel.com/ [2]
Link: https://lore.kernel.org/r/163819668938.215744.14448852181937731615.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163906979003.143852.2601189243864854724.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163967182112.1823006.7791504655391213379.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/164021575950.640689.12069642327533368467.stgit@warthog.procyon.org.uk/ # v4

NFS: Remove the nfs4_label from the nfs4_getattr_res

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Unexport nfs_probe_fsinfo()

All the callers are now in client.c so we can remove the
EXPORT_SYMBOL_GPL() and make it static.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Replace calls to nfs_probe_fsinfo() with nfs_probe_server()

Clean up. There are a few places where we want to probe the server, but
don't actually care about the fsinfo result. Change these to use
nfs_probe_server(), which handles the fattr allocation for us.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Move nfs_probe_destination() into the generic client

And rename it to nfs_probe_server(). I also change it to take the nfs_fh
as an argument so callers can choose what filehandle to probe.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

SUNRPC enforce creation of no more than max_connect xprts

If we are adding new transports via rpc_clnt_test_and_add_xprt()
then check if we've reached the limit. Currently only pnfs path
adds transports via that function but this is done in
preparation when the client would add new transports when
session trunking is detected. A warning is logged if the
limit is reached.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4 introduce max_connect mount options

This option will control up to how many xprts can the client
establish to the server with a distinct address (that means
nconnect connections are not counted towards this new limit).
This patch is setting up nfs structures to keeep track of the
max_connect limit (does not enforce it).

The default value is kept at 1 so that no current mounts that
don't want any additional connections would be effected. The
maximum value is set at 16.

Mounts to DS are not limited to default value of 1 but instead
set to the maximum default value of 16 (NFS_MAX_TRANSPORTS).

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Fix a potential NULL dereference in nfs_get_client()

None of the callers are expecting NULL returns from nfs_get_client() so
this code will lead to an Oops. It's better to return an error
pointer. I expect that this is dead code so hopefully no one is
affected.

Fixes: 31434f496abb ("nfs: check hostname in nfs_get_client")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Split attribute support out from the server capabilities

There are lots of attributes, and they are crowding out the bit space.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4: Add support for the NFSv4.2 "change_attr_type" attribute

The change_attr_type allows the server to provide a description of how
the change attribute will behave. This again will allow the client to
optimise its behaviour w.r.t. attribute revalidation.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Fix up the support for CONFIG_NFS_DISABLE_UDP_SUPPORT

Rather than removing the support in nfs_init_timeout_values(), we should
just fix up the validation checks in the mount option parsers.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: NFSv2/NFSv3: Use cred from fs_context during mount

There was refactoring done to use the fs_context for mounting done in:
62a55d088cd87: NFS: Additional refactoring for fs_context conversion

This made it so that the net_ns is fetched from the fs_context (the netns
that fsopen is called in). This change also makes it so that the credential
fetched during fsopen is used as well as the net_ns.

NFS has already had a number of changes to prepare it for user namespaces:
1a58e8a0e5c1: NFS: Store the credential of the mount process in the nfs_server
264d948ce7d0: NFS: Convert NFSv3 to use the container user namespace
c207db2f5da5: NFS: Convert NFSv2 to use the container user namespace

Previously, different credentials could be used for creation of the
fs_context versus creation of the nfs_server, as FSCONFIG_CMD_CREATE did
the actual credential check, and that's where current_creds() were fetched.
This meant that the user namespace which fsopen was called in could be a
non-init user namespace. This still requires that the user that calls
FSCONFIG_CMD_CREATE has CAP_SYS_ADMIN in the init user ns.

This roughly allows a privileged user to mount on behalf of an unprivileged
usernamespace, by forking off and calling fsopen in the unprivileged user
namespace. It can then pass back that fsfd to the privileged process which
can configure the NFS mount, and then it can call FSCONFIG_CMD_CREATE
before switching back into the mount namespace of the container, and finish
up the mounting process and call fsmount and move_mount.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Tested-by: Alban Crequy <alban.crequy@gmail.com>
Fixes: 62a55d088cd8 ("NFS: Additional refactoring for fs_context conversion")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Support larger readdir buffers

Support readdir buffers of up to 1MB in size so that we can read
large directories using few RPC calls.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

NFSv4.2: query the server for extended attribute support

Query the server for extended attribute support, and record it
as the NFS_CAP_XATTR flag in the server capabilities.

Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2: define limits and sizes for user xattr handling

Set limits for extended attributes (attribute value size and listxattr
buffer size), based on the fs-independent limits (XATTR_*_MAX).

Define the maximum XDR sizes for the RFC 8276 XATTR operations.
In the case of operations that carry a larger payload (SETXATTR,
GETXATTR, LISTXATTR), these exclude that payload, which is added
as separate pages, like other operations do.

Define, much like for read and write operations, the maximum overhead
sizes for get/set/listxattr, and use them to limit the maximum payload
size for those operations, in combination with the channel attributes.

Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

nfs: add minor version to nfs_server_key for fscache

An NFS client that mounts multiple exports from the same NFS
server with higher NFSv4 versions disabled (i.e. 4.2) and without
forcing a specific NFS version results in fscache index cookie
collisions and the following messages:
[ 570.004348] FS-Cache: Duplicate cookie detected

Each nfs_client structure should have its own fscache index cookie,
so add the minorversion to nfs_server_key.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=200145
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: allow deprecation of NFS UDP protocol

Add a kernel config CONFIG_NFS_DISABLE_UDP_SUPPORT to disallow NFS
UDP mounts and enable it by default.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Additional refactoring for fs_context conversion

Split out from commit "NFS: Add fs_context support."

This patch adds additional refactoring for the conversion of NFS to use
fs_context, namely:

(*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context.
nfs_clone_mount has had several fields removed, and nfs_mount_info
has been removed altogether.
(*) Various functions now take an fs_context as an argument instead
of nfs_mount_info, nfs_fs_context, etc.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: rename nfs_fs_context pointer arg in a few functions

Split out from commit "NFS: Add fs_context support."

Rename cfg to ctx in nfs_init_server(), nfs_verify_authflavors(),
and nfs_request_mount(). No functional changes.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Rename struct nfs_parsed_mount_data to struct nfs_fs_context

Rename struct nfs_parsed_mount_data to struct nfs_fs_context and rename
pointers to it to "ctx". At some point this will be pointed to by an
fs_context struct's fs_private pointer.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

nfs: don't pass nfs_subversion to ->create_server()

pick it from mount_info

Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4.1: Don't rebind to the same source port when reconnecting to the server

NFSv2, v3 and NFSv4 servers often have duplicate replay caches that look
at the source port when deciding whether or not an RPC call is a replay
of a previous call. This requires clients to perform strange TCP gymnastics
in order to ensure that when they reconnect to the server, they bind
to the same source port.

NFSv4.1 and NFSv4.2 have sessions that provide proper replay semantics,
that do not look at the source port of the connection. This patch therefore
ensures they can ignore the rebind requirement.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS/pnfs: Separate NFSv3 DS and MDS traffic

If a NFSv3 server is being used as both a DS and as a regular NFSv3 server,
we may want to keep the IO traffic on a separate TCP connection, since
it will typically have very different timeout characteristics.

This patch therefore sets up a flag to separate the two modes of operation
for the nfs_client.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Add a flag to tell nfs_client to set RPC_CLNT_CREATE_NOPING

Add a flag to tell the nfs_client it should set RPC_CLNT_CREATE_NOPING when
creating the rpc client.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Cleanup if nfs_match_client is interrupted

Don't bail out before cleaning up a new allocation if the wait for
searching for a matching nfs client is interrupted. Memory leaks.

Reported-by: syzbot+7fe11b49c1cc30e3fce2@syzkaller.appspotmail.com
Fixes: 950a578c6128 ("NFS: make nfs_match_client killable")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Allow multiple connections to a NFSv2 or NFSv3 server

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4: Allow multiple connections to NFSv4.x (x>0) servers

If the user specifies the -onconn=<number> mount option, and the transport
protocol is TCP, then set up <number> connections to the server. The
connections will all go to the same IP address.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Add sysfs support for per-container identifier

In order to identify containers to the NFS client, we add a per-net
sysfs attribute that udev can fill with the appropriate identifier.
The identifier could be a unique hostname, but in most cases it
will probably be a persisted uuid.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Cleanup - add nfs_clients_exit to mirror nfs_clients_init

Add a helper to clean up the struct nfs_net when it is being destroyed.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFS: Fix a double unlock from nfs_match,get_client

Now that nfs_match_client drops the nfs_client_lock, we should be
careful
to always return it in the same condition: locked.

Fixes: 950a578c6128 ("NFS: make nfs_match_client killable")
Reported-by: syzbot+228a82b263b5da91883d@syzkaller.appspotmail.com
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: make nfs_match_client killable

Actually we don't do anything with return value from
nfs_wait_client_init_complete in nfs_match_client, as a
consequence if we get a fatal signal and client is not
fully initialised, we'll loop to "again" label

This has been proven to cause soft lockups on some scenarios
(no-carrier but configured network interfaces)

Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Store the credential of the mount process in the nfs_server

Store the credential of the mount process so that we can determine
information such as the user namespace.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

SUNRPC: Cache cred of process creating the rpc_client

When converting kuids to AUTH_UNIX creds, etc we will want to use the
same user namespace as the process that created the rpc client.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Add a mount option "softerr" to allow clients to see ETIMEDOUT errors

Add a mount option that exposes the ETIMEDOUT errors that occur during
soft timeouts to the application. This allows aware applications to
distinguish between server disk IO errors and client timeout errors.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

lockd: Pass the user cred from knfsd when starting the lockd server

When starting up a new knfsd server, pass the user cred to the
supporting lockd server.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

NFS: Fix a typo in nfs_init_timeout_values()

Specifying a retrans=0 mount parameter to a NFS/TCP mount, is
inadvertently causing the NFS client to rewrite any specified
timeout parameter to the default of 60 seconds.

Fixes: a956beda19a6 ("NFS: Allow the mount option retrans=0")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS/SUNRPC: don't lookup machine credential until rpcauth_bindcred().

When NFS creates a machine credential, it is a "generic" credential,
not tied to any auth protocol, and is really just a container for
the princpal name.
This doesn't get linked to a genuine credential until rpcauth_bindcred()
is called.
The lookup always succeeds, so various places that test if the machine
credential is NULL, are pointless.

As a step towards getting rid of generic credentials, this patch gets
rid of generic machine credentials. The nfs_client and rpc_client
just hold a pointer to a constant principal name.
When a machine credential is wanted, a special static 'struct rpc_cred'
pointer is used. rpcauth_bindcred() recognizes this, finds the
principal from the client, and binds the correct credential.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4: add cl_root_cred for use when machine cred is not available.

NFSv4 state management tries a root credential when no machine
credential is available, as can happen with kerberos.
It does this by replacing the cl_machine_cred with a root credential.
This means that any user of the machine credential needs to take
a lock while getting a reference to the machine credential, which is
a little cumbersome.

So introduce an explicit cl_root_cred, and never free either
credential until client shutdown. This means that no locking
is needed to reference these credentials. Future patches
will make use of this.

This is only a temporary addition. both cl_machine_cred and
cl_root_cred will disappear later in the series.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS add support for asynchronous COPY

Change xdr to always send COPY asynchronously.

Keep the list copies send in a list under a server structure.
Once copy is sent, it waits on a completion structure that will
be signalled by the callback thread that receives CB_OFFLOAD.

If CB_OFFLOAD returned an error and even if it returned partial
bytes, ignore them (as we can't commit without a verifier to
match) and return an error.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Pass the inode down to the getattr() callback

Allow the getattr() callback to check things like whether or not we hold
a delegation so that it can adjust the attributes that it is asking for.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

proc: introduce proc_create_net{,_data}

Variants of proc_create{,_data} that directly take a struct seq_operations
and deal with network namespaces in ->open and ->release. All callers of
proc_create + seq_open_net converted over, and seq_{open,release}_net are
removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>

nfs: fix a deadlock in nfs client initialization

The following deadlock can occur between a process waiting for a client
to initialize in while walking the client list during nfsv4 server trunking
detection and another process waiting for the nfs_clid_init_mutex so it
can initialize that client:

Process 1 Process 2
--------- ---------
spin_lock(&nn->nfs_client_lock);
list_add_tail(&CLIENTA->cl_share_link,
&nn->nfs_client_list);
spin_unlock(&nn->nfs_client_lock);
spin_lock(&nn->nfs_client_lock);
list_add_tail(&CLIENTB->cl_share_link,
&nn->nfs_client_list);
spin_unlock(&nn->nfs_client_lock);
mutex_lock(&nfs_clid_init_mutex);
nfs41_walk_client_list(clp, result, cred);
nfs_wait_client_init_complete(CLIENTA);
(waiting for nfs_clid_init_mutex)

Make sure nfs_match_client() only evaluates clients that have completed
initialization in order to prevent that deadlock.

This patch also fixes v4.0 trunking behavior by not marking the client
NFS_CS_READY until the clientid has been confirmed.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs, nfs: convert nfs_client.cl_count from atomic_t to refcount_t

atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable nfs_client.cl_count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Fix uninitialized rpc_wait_queue

Michael Sterrett reports a NULL pointer dereference on NFSv3 mounts when
CONFIG_NFS_V4 is not set because the NFS UOC rpc_wait_queue has not been
initialized. Move the initialization of the queue out of the CONFIG_NFS_V4
conditional setion.

Fixes: 7d6ddf88c4db ("NFS: Add an iocounter wait function for async RPC tasks")
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

mount: copy the port field into the cloned nfs_server structure.

Doing this copy eliminates the "port=0" entry in
the /proc/mounts entries

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=69241

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

lockd: Introduce nlmclnt_operations

NFS would enjoy the ability to modify the behavior of the NLM client's
unlock RPC task in order to delay the transmission of the unlock until IO
that was submitted under that lock has completed. This ability can ensure
that the NLM client will always complete the transmission of an unlock even
if the waiting caller has been interrupted with fatal signal.

For this purpose, a pointer to a struct nlmclnt_operations can be assigned
in a nfs_module's nfs_rpc_ops that will install those nlmclnt_operations on
the nlm_host. The struct nlmclnt_operations defines three callback
operations that will be used in a following patch:

nlmclnt_alloc_call - used to call back after a successful allocation of
a struct nlm_rqst in nlmclnt_proc().

nlmclnt_unlock_prepare - used to call back during NLM unlock's
rpc_call_prepare. The NLM client defers calling rpc_call_start()
until this callback returns false.

nlmclnt_release_call - used to call back when the NLM client's struct
nlm_rqst is freed.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Add an iocounter wait function for async RPC tasks

By sleeping on a new NFS Unlock-On-Close waitqueue, rpc tasks may wait for
a lock context's iocounter to reach zero. The rpc waitqueue is only woken
when the open_context has the NFS_CONTEXT_UNLOCK flag set in order to
mitigate spurious wake-ups for any iocounter reaching zero.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: Convert to separately allocated bdi

Allocate struct backing_dev_info separately instead of embedding it
inside the superblock. This unifies handling of bdi among users.

CC: Anna Schumaker <anna.schumaker@netapp.com>
CC: linux-nfs@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

NFS: Clean up extra dprintk()s in client.c

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Clean up nfs_init_client()

We always call nfs_mark_client_ready() even if nfs_create_rpc_client()
returns an error, so we can rearrange nfs_init_client() to mark the
client ready from a single place.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

pNFS: return status from nfs4_pnfs_ds_connect

The nfs4_pnfs_ds_connect path can call rpc_create which can fail or it
can wait on another context to reach the same failure.

This checks that the rpc_create succeeded and returns the error to the
caller.

When an error is returned, both the files and flexfiles layouts will return
NULL from _prepare_ds(). The flexfiles layout will also return the layout
with the error NFS4ERR_NXIO.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Remove unused authflavour parameter from nfs_get_client()

This parameter hasn't been used since f8407299 (Linux 3.11-rc2), so
let's remove it from this function and callers.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Ignore connections that have cl_rpcclient uninitialized

cl_rpcclient starts as ERR_PTR(-EINVAL), and connections like that
are floating freely through the system. Most places check whether
pointer is valid before dereferencing it, but newly added code
in nfs_match_client does not.

Which causes crashes when more than one NFS mount point is present.

Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs: nfs: Make nfs boot time y2038 safe

boot_time is represented as a struct timespec.
struct timespec and CURRENT_TIME are not y2038 safe.
Overall, the plan is to use timespec64 and ktime_t for
all internal kernel representation of timestamps.
CURRENT_TIME will also be removed.

boot_time is used to construct the nfs client boot verifier.

Use ktime_t to represent boot_time and ktime_get_real() for
the boot_time value.

Following Trond's request https://lkml.org/lkml/2016/6/9/22 ,
use ktime_t instead of converting to struct timespec64.

Use higher and lower 32 bit parts of ktime_t for the boot
verifier.

Use the lower 32 bit part of ktime_t for the authsys_parms
stamp field.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

pnfs: add a new mechanism to select a layout driver according to an ordered list

Currently, the layout driver selection code always chooses the first one
from the list. That's not really ideal however, as the server can send
the list of layout types in any order that it likes. It's up to the
client to select the best one for its needs.

This patch adds an ordered list of preferred driver types and has the
selection code sort the list of available layout drivers according to it.
Any unrecognized layout type is sorted to the end of the list.

For now, the order of preference is hardcoded, but it should be possible
to make this configurable in the future.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS add xprt switch addrs test to match client

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

pnfs: track multiple layout types in fsinfo structure

Current NFSv4.1/pNFS client assumes that MDS supports only one layout
type. While it's true for most existing servers, nevertheless, this can
be change in the near future.

For now, this patch just plumbs in the ability to track a list of
layouts in the fsinfo structure. The existing behavior of the client
is preserved, by having it just select the first entry in the list.

Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Allow the mount option retrans=0

We should allow retrans=0 as just meaning that every timeout is a major
timeout, and that there is no increment in the timeout value.

For instance, this means that we would allow TCP users to specify a
flat timeout value of 60s, by specifying "timeo=600,retrans=0" in their
mount option string.

Siged-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Fix an Oops in the pNFS files and flexfiles connection setup to the DS

Chris Worley reports:
RIP: 0010:[<ffffffffa0245f80>] [<ffffffffa0245f80>] rpc_new_client+0x2a0/0x2e0 [sunrpc]
RSP: 0018:ffff880158f6f548 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff880234f8bc00 RCX: 000000000000ea60
RDX: 0000000000074cc0 RSI: 000000000000ea60 RDI: ffff880234f8bcf0
RBP: ffff880158f6f588 R08: 000000000001ac80 R09: ffff880237003300
R10: ffff880201171000 R11: ffffea0000d75200 R12: ffffffffa03afc60
R13: ffff880230c18800 R14: 0000000000000000 R15: ffff880158f6f680
FS: 00007f0e32673740(0000) GS:ffff88023fc40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000008 CR3: 0000000234886000 CR4: 00000000001406e0
Stack:
ffffffffa047a680 0000000000000000 ffff880158f6f598 ffff880158f6f680
ffff880158f6f680 ffff880234d11d00 ffff88023357f800 ffff880158f6f7d0
ffff880158f6f5b8 ffffffffa024660a ffff880158f6f5b8 ffffffffa02492ec
Call Trace:
[<ffffffffa024660a>] rpc_create_xprt+0x1a/0xb0 [sunrpc]
[<ffffffffa02492ec>] ? xprt_create_transport+0x13c/0x240 [sunrpc]
[<ffffffffa0246766>] rpc_create+0xc6/0x1a0 [sunrpc]
[<ffffffffa038e695>] nfs_create_rpc_client+0xf5/0x140 [nfs]
[<ffffffffa038f31a>] nfs_init_client+0x3a/0xd0 [nfs]
[<ffffffffa038f22f>] nfs_get_client+0x25f/0x310 [nfs]
[<ffffffffa025cef8>] ? rpc_ntop+0xe8/0x100 [sunrpc]
[<ffffffffa047512c>] nfs3_set_ds_client+0xcc/0x100 [nfsv3]
[<ffffffffa041fa10>] nfs4_pnfs_ds_connect+0x120/0x400 [nfsv4]
[<ffffffffa03d41c7>] nfs4_ff_layout_prepare_ds+0xe7/0x330 [nfs_layout_flexfiles]
[<ffffffffa03d1b1b>] ff_layout_pg_init_write+0xcb/0x280 [nfs_layout_flexfiles]
[<ffffffffa03a14dc>] __nfs_pageio_add_request+0x12c/0x490 [nfs]
[<ffffffffa03a1fa2>] nfs_pageio_add_request+0xc2/0x2a0 [nfs]
[<ffffffffa03a0365>] ? nfs_pageio_init+0x75/0x120 [nfs]
[<ffffffffa03a5b50>] nfs_do_writepage+0x120/0x270 [nfs]
[<ffffffffa03a5d31>] nfs_writepage_locked+0x61/0xc0 [nfs]
[<ffffffff813d4115>] ? __percpu_counter_add+0x55/0x70
[<ffffffffa03a6a9f>] nfs_wb_single_page+0xef/0x1c0 [nfs]
[<ffffffff811ca4a3>] ? __dec_zone_page_state+0x33/0x40
[<ffffffffa0395b21>] nfs_launder_page+0x41/0x90 [nfs]
[<ffffffff811baba0>] invalidate_inode_pages2_range+0x340/0x3a0
[<ffffffff811bac17>] invalidate_inode_pages2+0x17/0x20
[<ffffffffa039960e>] nfs_release+0x9e/0xb0 [nfs]
[<ffffffffa0399570>] ? nfs_open+0x60/0x60 [nfs]
[<ffffffffa0394dad>] nfs_file_release+0x3d/0x60 [nfs]
[<ffffffff81226e6c>] __fput+0xdc/0x1e0
[<ffffffff81226fbe>] ____fput+0xe/0x10
[<ffffffff810bf2e4>] task_work_run+0xc4/0xe0
[<ffffffff810a4188>] do_exit+0x2e8/0xb30
[<ffffffff8102471c>] ? do_audit_syscall_entry+0x6c/0x70
[<ffffffff811464e6>] ? __audit_syscall_exit+0x1e6/0x280
[<ffffffff810a4a5f>] do_group_exit+0x3f/0xa0
[<ffffffff810a4ad4>] SyS_exit_group+0x14/0x20
[<ffffffff8179b76e>] system_call_fastpath+0x12/0x71

Which seems to be due to a call to utsname() when in a task exit context
in order to determine the hostname to set in rpc_new_client().

In reality, what we want here is not the hostname of the current task, but
the hostname that was used to set up the metadata server.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

drop redundant ->owner initializations

it's not needed for file_operations of inodes located on fs defined
in the hosting module and for file_operations that go into procfs.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized. And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special. They are
not.

The changes are pretty straight-forward:

- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

- page_cache_get() -> get_page();

- page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nfs: get clone_blksize when probing fsinfo

NFSv42 CLONE operation is supposed to respect it.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Use RPC functions for matching sockaddrs

They already exist and do the exact same thing. Let's save ourselves
several lines of code!

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Remove the "NFS_CAP_CHANGE_ATTR" capability

Setting the change attribute has been mandatory for all NFS versions, since
commit 3a1556e8662c ("NFSv2/v3: Simulate the change attribute"). We should
therefore not have anything be conditional on it being set/unset.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: Use remove_proc_subtree() instead remove_proc_entry()

Thanks for Al Viro's comments of killing proc_fs_nfs completely.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: Remove unused argument in nfs_server_set_fsinfo()

Commit e38eb6506f "NFS: set_pnfs_layoutdriver() from nfs4_proc_fsinfo()"
have remove the using of mntfh from nfs_server_set_fsinfo().

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: Fix showing truncated fsid/dev in, /proc/net/nfsfs/volumes

A truncated fsid showing from /proc/fs/nfsfs/volumes as,
NV SERVER PORT DEV FSID FSC
v4 c0a80881 801 0:43 34931f044c2a439b no

It should be as,
NV SERVER PORT DEV FSID FSC
v4 c0a80881 801 0:43 34931f044c2a439b:954c5d830fa4be8c no

The max buffer length for storing "%llx:%llx" format should be
16 + 1 + 16 + 1 = 34 (16 for %llx, 1 for ':', 1 for '\0').

Also, for storing "%u:%u" of MAJOR() and MINOR() should be
8 + 1 + 3 + 1 = 13 (8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0').

v2, add comments for dev/fsid buffer and use sizeof in snprintf.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Remove CONFIG_NFS_V4 checks from nfs_idmap.h

The idmapper is completely internal to the NFS v4 module, so this macro
will always evaluate to true. This patch also removes unnecessary
includes of this file from the generic NFS client.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFSv4: Fix a race in NFSv4.1 server trunking discovery

We do not want to allow a race with another NFS mount to cause
nfs41_walk_client_list() to establish a lease on our nfs_client before
we're done checking for trunking.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: fix duplicate proc entries

Commit 65b38851a174
("NFS: Fix /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes")

updated the following function:
static int nfs_volume_list_open(struct inode *inode, struct file *file)

it used &nfs_server_list_ops instead of &nfs_volume_list_ops
which means cat /proc/fs/nfsfs/volumes = /proc/fs/nfsfs/servers

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Fixes: 65b38851a174 (NFS: Fix /proc/fs/nfsfs/servers and...)
Cc: stable@vger.kernel.org # 3.4.x+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: add __acquires and __releases annotations to seqfile start/stop routines

To make sparse happy...

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: fix kernel warning when removing proc entry

I saw the following kernel warning:

[ 1852.321222] ------------[ cut here ]------------
[ 1852.326527] WARNING: CPU: 0 PID: 118 at fs/proc/generic.c:521 remove_proc_entry+0x154/0x16b()
[ 1852.335630] remove_proc_entry: removing non-empty directory 'fs/nfsfs', leaking at least 'volumes'
[ 1852.344084] CPU: 0 PID: 118 Comm: kworker/u8:2 Not tainted 3.16.0+ #540
[ 1852.350036] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1852.354992] Workqueue: netns cleanup_net
[ 1852.358701] 0000000000000000 ffff880116f2fbd0 ffffffff819c03e9 ffff880116f2fc18
[ 1852.366474] ffff880116f2fc08 ffffffff810744ee ffffffff811e0e6e ffff8800d4e96238
[ 1852.373507] ffffffff81dbe665 ffff8800d46a5948 0000000000000005 ffff880116f2fc68
[ 1852.380224] Call Trace:
[ 1852.381976] [<ffffffff819c03e9>] dump_stack+0x4d/0x66
[ 1852.385495] [<ffffffff810744ee>] warn_slowpath_common+0x7a/0x93
[ 1852.389869] [<ffffffff811e0e6e>] ? remove_proc_entry+0x154/0x16b
[ 1852.393987] [<ffffffff8107457b>] warn_slowpath_fmt+0x4c/0x4e
[ 1852.397999] [<ffffffff811e0e6e>] remove_proc_entry+0x154/0x16b
[ 1852.402034] [<ffffffff8129c73d>] nfs_fs_proc_net_exit+0x53/0x56
[ 1852.406136] [<ffffffff812a103b>] nfs_net_exit+0x12/0x1d
[ 1852.409774] [<ffffffff81785bc9>] ops_exit_list+0x44/0x55
[ 1852.413529] [<ffffffff81786389>] cleanup_net+0xee/0x182
[ 1852.417198] [<ffffffff81088c9e>] process_one_work+0x209/0x40d
[ 1852.502320] [<ffffffff81088bf7>] ? process_one_work+0x162/0x40d
[ 1852.587629] [<ffffffff810890c1>] worker_thread+0x1f0/0x2c7
[ 1852.673291] [<ffffffff81088ed1>] ? process_scheduled_works+0x2f/0x2f
[ 1852.759470] [<ffffffff8108e079>] kthread+0xc9/0xd1
[ 1852.843099] [<ffffffff8109427f>] ? finish_task_switch+0x3a/0xce
[ 1852.926518] [<ffffffff8108dfb0>] ? __kthread_parkme+0x61/0x61
[ 1853.008565] [<ffffffff819cbeac>] ret_from_fork+0x7c/0xb0
[ 1853.076477] [<ffffffff8108dfb0>] ? __kthread_parkme+0x61/0x61
[ 1853.140653] ---[ end trace 69c4c6617f78e32d ]---

It looks wrong that we add "/proc/net/nfsfs" in nfs_fs_proc_net_init()
while remove "/proc/fs/nfsfs" in nfs_fs_proc_net_exit().

Fixes: commit 65b38851a17 (NFS: Fix /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes)
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Dan Aloni <dan@kernelim.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
[Trond: replace uses of remove_proc_entry() with remove_proc_subtree()
as suggested by Al Viro]
Cc: stable@vger.kernel.org # 3.4.x : 65b38851a17: NFS: Fix /proc/fs/nfsfs/servers
Cc: stable@vger.kernel.org # 3.4.x
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Fix /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes

The usage of pid_ns->child_reaper->nsproxy->net_ns in
nfs_server_list_open and nfs_client_list_open is not safe.

/proc for a pid namespace can remain mounted after the all of the
process in that pid namespace have exited. There are also times
before the initial process in a pid namespace has started or after the
initial process in a pid namespace has exited where
pid_ns->child_reaper can be NULL or stale. Making the idiom
pid_ns->child_reaper->nsproxy a double whammy of problems.

Luckily all that needs to happen is to move /proc/fs/nfsfs/servers and
/proc/fs/nfsfs/volumes under /proc/net to /proc/net/nfsfs/servers and
/proc/net/nfsfs/volumes and add a symlink from the original location,
and to use seq_open_net as it has been designed.

Cc: stable@vger.kernel.org
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

NFS: add checks for returned value of try_module_get()

There is a couple of places in client code where returned value
of try_module_get() is ignored. As a result there is a small chance
to premature unload module because of unbalanced refcounting.

The patch adds error handling in that places.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs4: copy acceptor name from context to nfs_client

The current CB_COMPOUND handling code tries to compare the principal
name of the request with the cl_hostname in the client. This is not
guaranteed to ever work, particularly if the client happened to mount
a CNAME of the server or a non-fqdn.

Fix this by instead comparing the cr_principal string with the acceptor
name that we get from gssd. In the event that gssd didn't send one
down (i.e. it was too old), then we fall back to trying to use the
cl_hostname as we do today.

Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: check hostname in nfs_get_client

We reference cl_hostname in many places. Add a check to make
sure it exists.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: cache parsed auth_info in nfs_server

Cache the auth_info structure in nfs_server and pass these values to submounts.

This lays the groundwork for supporting multiple sec= options.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: separate passed security flavs from selected

When filling parsed_mount_data, store the parsed sec= mount option in
the new struct nfs_auth_info and the chosen flavor in selected_flavor.

This patch lays the groundwork for supporting multiple sec= options.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Add nfs4_update_server

New function nfs4_update_server() moves an nfs_server to a different
nfs_client. This is done as part of migration recovery.

Though it may be appealing to think of them as the same thing,
migration recovery is not the same as following a referral.

For a referral, the client has not descended into the file system
yet: it has no nfs_server, no super block, no inodes or open state.
It is enough to simply instantiate the nfs_server and super block,
and perform a referral mount.

For a migration, however, we have all of those things already, and
they have to be moved to a different nfs_client. No local namespace
changes are needed here.

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

NFSv4: Ensure that we disable the resend timeout for NFSv4

The spec states that the client should not resend requests because
the server will disconnect if it needs to drop an RPC request.

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

NFS Remove unused authflavour parameter from init_client

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Set NFS_CS_MIGRATION for NFSv4 mounts

NFS_CS_MIGRATION makes sense only for NFSv4 mounts. Introduced by
commit 89652617 (NFS: Introduce "migration" mount option) Fri Sep 14
17:24:11 2012.

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

NFS:Add labels to client function prototypes

After looking at all of the nfsv4 operations the label structure has been added
to the prototypes of the functions which can transmit label data.

Signed-off-by: Matthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: Set the RPC_CLNT_CREATE_INFINITE_SLOTS flag for NFSv4.1 transports

This ensures that the RPC layer doesn't override the NFS session
negotiation.

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

nfs: idr_destroy() no longer needs idr_remove_all()

idr_destroy() can destroy idr by itself and idr_remove_all() is being
deprecated. Drop reference to idr_remove_all(). Note that the code
wasn't completely correct before because idr_remove() on all entries
doesn't necessarily release all idr_layers which could lead to memory
leak.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NFS: avoid NULL dereference in nfs_destroy_server

In rare circumstances, nfs_clone_server() of a v2 or v3 server can get
an error between setting server->destory (to nfs_destroy_server), and
calling nfs_start_lockd (which will set server->nlm_host).

If this happens, nfs_clone_server will call nfs_free_server which
will call nfs_destroy_server and thence nlmclnt_done(NULL). This
causes the NULL to be dereferenced.

So add a guard to only call nlmclnt_done() if ->nlm_host is not NULL.

The other guards there are irrelevant as nlm_host can only be non-NULL
if one of these flags are set - so remove those tests. (Thanks to Trond
for this suggestion).

This is suitable for any stable kernel since 2.6.25.

Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Get rid of unnecessary asserts

If the nfs_client fails to initialise correctly, then it will
return an error condition.

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

NFS: Remove unnecessary semicolons (fs/nfs/client.c)

There are some unnecessary semicolons in function find_nfs_version. Just remove them.

Signed-off-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS41: fix error of setting blocklayoutdriver

After commit e38eb650 (NFS: set_pnfs_layoutdriver() from
nfs4_proc_fsinfo()), set_pnfs_layoutdriver() is called inside
nfs4_proc_fsinfo(), but pnfs_blksize is not set. It causes setting
blocklayoutdriver failure and pnfsblock mount failure.

Cc: stable <stable@vger.kernel.org> [since v3.5]
Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Discover NFSv4 server trunking when mounting

"Server trunking" is a fancy named for a multi-homed NFS server.
Trunking might occur if a client sends NFS requests for a single
workload to multiple network interfaces on the same server. There
are some implications for NFSv4 state management that make it useful
for a client to know if a single NFSv4 server instance is
multi-homed. (Note this is only a consideration for NFSv4, not for
legacy versions of NFS, which are stateless).

If a client cares about server trunking, no NFSv4 operations can
proceed until that client determines who it is talking to. Thus
server IP trunking discovery must be done when the client first
encounters an unfamiliar server IP address.

The nfs_get_client() function walks the nfs_client_list and matches
on server IP address. The outcome of that walk tells us immediately
if we have an unfamiliar server IP address. It invokes
nfs_init_client() in this case. Thus, nfs4_init_client() is a good
spot to perform trunking discovery.

Discovery requires a client to establish a fresh client ID, so our
client will now send SETCLIENTID or EXCHANGE_ID as the first NFS
operation after a successful ping, rather than waiting for an
application to perform an operation that requires NFSv4 state.

The exact process for detecting trunking is different for NFSv4.0 and
NFSv4.1, so a minorversion-specific init_client callout method is
introduced.

CLID_INUSE recovery is important for the trunking discovery process.
CLID_INUSE is a sign the server recognizes the client's nfs_client_id4
id string, but the client is using the wrong principal this time for
the SETCLIENTID operation. The SETCLIENTID must be retried with a
series of different principals until one works, and then the rest of
trunking discovery can proceed.

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

NFS: Introduce "migration" mount option

Currently, the Linux client uses a unique nfs_client_id4.id string
when identifying itself to distinct NFS servers.

To support transparent state migration, the Linux client will have to
use the same nfs_client_id4 string for all servers it communicates
with (also known as the "uniform client string" approach). Otherwise
NFS servers can not recognize that open and lock state need to be
merged after a file system transition.

Unfortunately, there are some NFSv4.0 servers currently in the field
that do not tolerate the uniform client string approach.

Thus, by default, our NFSv4.0 mounts will continue to use the current
approach, and we introduce a mount option that switches them to use
the uniform model. Client administrators must identify which servers
can be mounted with this option. Eventually most NFSv4.0 servers will
be able to handle the uniform approach, and we can change the default.

The first mount of a server controls the behavior for all subsequent
mounts for the lifetime of that set of mounts of that server. After
the last mount of that server is gone, the client erases the data
structure that tracks the lease. A subsequent lease may then honor
a different "migration" setting.

This patch adds only the infrastructure for parsing the new mount
option. Support for uniform client strings is added in a subsequent
patch.

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

SUNRPC: Introduce rpc_clone_client_set_auth()

An ULP is supposed to be able to replace a GSS rpc_auth object with
another GSS rpc_auth object using rpcauth_create(). However,
rpcauth_create() in 3.5 reliably fails with -EEXIST in this case.
This is because when gss_create() attempts to create the upcall pipes,
sometimes they are already there. For example if a pipe FS mount
event occurs, or a previous GSS flavor was in use for this rpc_clnt.

It turns out that's not the only problem here. While working on a
fix for the above problem, we noticed that replacing an rpc_clnt's
rpc_auth is not safe, since dereferencing the cl_auth field is not
protected in any way.

So we're deprecating the ability of rpcauth_create() to switch an
rpc_clnt's security flavor during normal operation. Instead, let's
add a fresh API that clones an rpc_clnt and gives the clone a new
flavor before it's used.

This makes immediate use of the new __rpc_clone_client() helper.

This can be used in a similar fashion to rpcauth_create() when a
client is hunting for the correct security flavor. Instead of
replacing an rpc_clnt's security flavor in a loop, the ULP replaces
the whole rpc_clnt.

To fix the -EEXIST problem, any ULP logic that relies on replacing
an rpc_clnt's rpc_auth with rpcauth_create() must be changed to use
this API instead.

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

NFS: Fix a regression when loading the NFS v4 module

Some systems have a modprobe.d/nfs.conf file that sets an nfs4 alias
pointing to nfs.ko, rather than nfs4.ko. This can prevent the v4 module
from loading on mount, since the kernel sees that something named "nfs4"
has already been loaded. To work around this, I've renamed the modules
to "nfsv2.ko" "nfsv3.ko" and "nfsv4.ko".

I also had to move the nfs4_fs_type back to nfs.ko to ensure that `mount
-t nfs4` still works.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Convert v4 into a module

This patch exports symbols needed by the v4 module. In addition, I also
switch over to using IS_ENABLED() to check if CONFIG_NFS_V4 or
CONFIG_NFS_V4_MODULE are set.

The module (nfs4.ko) will be created in the same directory as nfs.ko and
will be automatically loaded the first time you try to mount over NFS v4.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Convert v3 into a module

This patch exports symbols and moves over the final structures needed by
the v3 module. In addition, I also switch over to using IS_ENABLED() to
check if CONFIG_NFS_V3 or CONFIG_NFS_V3_MODULE are set.

The module (nfs3.ko) will be created in the same directory as nfs.ko and
will be automatically loaded the first time you try to mount over NFS v3.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Convert v2 into a module

The module (nfs2.ko) will be created in the same directory as nfs.ko and
will be automatically loaded the first time you try to mount over NFS v2.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Only initialize the ACL client in the v3 case

v2 and v4 don't use it, so I create two new nfs_rpc_ops functions to
initialize the ACL client only when we are using v3.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Add version registering framework

This patch adds in the code to track multiple versions of the NFS
protocol. I created default structures for v2, v3 and v4 so that each
version can continue to work while I convert them into kernel modules.
I also removed the const parameter from the rpc_version array so that I
can change it at runtime.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Split out NFS v4 client functions

These functions are only needed by NFS v4, so they can be moved into a
v4 specific file.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Split out NFS v4 server creating code

These functions are specific to NFS v4 and can be moved to nfs4client.c
to keep them out of the generic client.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Initialize the NFS v4 client from init_nfs_v4()

And split these functions out of the generic client into a v4 specific
file.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Create an alloc_client rpc_op

This gives NFS v4 a way to set up callbacks and sessions without v2 or
v3 having to do them as well.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Create a free_client rpc_op

NFS v4 needs a way to shut down callbacks and sessions, but v2 and v3
don't.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Use nfs4_destroy_server() to clean up NFS v4

I can use this function to return delegations and unset the pnfs layout
driver rather than continuing to do these things in the generic client.
With this change, we no longer need an nfs4_kill_super().

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: set_pnfs_layoutdriver() from nfs4_proc_fsinfo()

The generic client doesn't need to know about pnfs layout drivers, so
this should be done in the v4 code.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: Fix umount when filelayout DS is also the MDS

Currently there is a 'chicken and egg' issue when the DS is also the mounted
MDS. The nfs_match_client() reference from nfs4_set_ds_client bumps the
cl_count, the nfs_client is not freed at umount, and nfs4_deviceid_purge_client
is not called to dereference the MDS usage of a deviceid which holds a
reference to the DS nfs_client. The result is the umount program returns,
but the nfs_client is not freed, and the cl_session hearbeat continues.

The MDS (and all other nfs mounts) lose their last nfs_client reference in
nfs_free_server when the last nfs_server (fsid) is umounted.
The file layout DS lose their last nfs_client reference in destroy_ds
when the last deviceid referencing the data server is put and destroy_ds is
called. This is triggered by a call to nfs4_deviceid_purge_client which
removes references to a pNFS deviceid used by an MDS mount.

The fix is to track how many pnfs enabled filesystems are mounted from
this server, and then to purge the device id cache once that count reaches
zero.

Reported-by: Jorge Mora <Jorge.Mora@netapp.com>
Reported-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Remove incorrect BUG_ON in nfs_found_client

It is perfectly valid for nfs_get_client() to return a nfs_client that
is in the process of setting up the NFSv4.1 session.

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

NFSv4.1: Add DESTROY_CLIENTID

Ensure that we destroy our lease on last unmount

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

NFS: Add memory barriers to the nfs_client->cl_cons_state initialisation

Ensure that a process that uses the nfs_client->cl_cons_state test
for whether the initialisation process is finished does not read
stale data.

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

NFSv4: Fix a race in the net namespace mount notification

Since the struct nfs_client gets added to the global nfs_client_list
before it is initialised, it is possible that rpc_pipefs_event can
end up trying to create idmapper entries on such a thing.

The solution is to have the mount notification wait for the
initialisation of each nfs_client to complete, and then to
skip any entries for which the it failed.

Reported-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

NFSv4.1: Fix session initialisation races

Session initialisation is not complete until the lease manager
has run. We need to ensure that both nfs4_init_session and
nfs4_init_ds_session do so, and that they check for any resulting
errors in clp->cl_cons_state.

Only after this is done, can nfs4_ds_connect check the contents
of clp->cl_exchange_flags.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Andy Adamson <andros@netapp.com>

NFS: EXCHANGE_ID should save the server major and minor ID

Save the server major and minor ID results from EXCHANGE_ID, as they
are needed for detecting server trunking.

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

NFS: Add nfs_client behavior flags

"noresvport" and "discrtry" can be passed to nfs_create_rpc_client()
by setting flags in the passed-in nfs_client. This change makes it
easy to add new flags.

Note that these settings are now "sticky" over the lifetime of a
struct nfs_client, and may even be copied when an nfs_client is
cloned.

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

NFS: Refactor nfs_get_client(): initialize nfs_client

Clean up: Continue to rationalize the locking in nfs_get_client() by
moving the logic that handles the case where a matching server IP
address is not found.

When we support server trunking detection, client initialization may
return a different nfs_client struct than was passed to it. Change
the synopsis of the init_client methods to return an nfs_client.

The client initialization logic in nfs_get_client() is not much more
than a wrapper around ->init_client. It's simpler to keep the little
bits of error handling in the version-specific init_client methods.

No behavior change is expected.

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

NFS: Refactor nfs_get_client(): add nfs_found_client()

Clean up: Code that takes and releases nfs_client_lock remains in
nfs_get_client(). Logic that handles a pre-existing nfs_client is
moved to a separate function.

No behavior change is expected.

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

NFS: Always use the same SETCLIENTID boot verifier

Currently our NFS client assigns a unique SETCLIENTID boot verifier
for each server IP address it knows about. It's set to CURRENT_TIME
when the struct nfs_client for that server IP is created.

During the SETCLIENTID operation, our client also presents an
nfs_client_id4 string to servers, as an identifier on which the server
can hang all of this client's NFSv4 state. Our client's
nfs_client_id4 string is unique for each server IP address.

An NFSv4 server is obligated to wipe all NFSv4 state associated with
an nfs_client_id4 string when the client presents the same
nfs_client_id4 string along with a changed SETCLIENTID boot verifier.

When our client unmounts the last of a server's shares, it destroys
that server's struct nfs_client. The next time the client mounts that
NFS server, it creates a fresh struct nfs_client with a fresh boot
verifier. On seeing the fresh verifer, the server wipes any previous
NFSv4 state associated with that nfs_client_id4.

However, NFSv4.1 clients are supposed to present the same
nfs_client_id4 string to all servers. And, to support Transparent
State Migration, the same nfs_client_id4 string should be presented
to all NFSv4.0 servers so they recognize that migrated state for this
client belongs with state a server may already have for this client.
(This is known as the Uniform Client String model).

If the nfs_client_id4 string is the same but the boot verifier changes
for each server IP address, SETCLIENTID and EXCHANGE_ID operations
from such a client could unintentionally result in a server wiping a
client's previously obtained lease.

Thus, if our NFS client is going to use a fixed nfs_client_id4 string,
either for NFSv4.0 or NFSv4.1 mounts, our NFS client should use a
boot verifier that does not change depending on server IP address.
Replace our current per-nfs_client boot verifier with a per-nfs_net
boot verifier.

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

NFS: Use proper naming conventions for the nfs_client.net field

Clean up: When naming fields and data types, follow established
conventions to facilitate accurate grep/cscope searches.

Introduced by commit e50a7a1a "NFS: make NFS client allocated per
network namespace context," Tue Jan 10, 2012.

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

NFS: Use proper naming conventions for nfs_client.impl_id field

Clean up: When naming fields and data types, follow established
conventions to facilitate accurate grep/cscope searches.

Additionally, for consistency, move the impl_id field into the NFSv4-
specific part of the nfs_client, and free that memory in the logic
that shuts down NFSv4 nfs_clients.

Introduced by commit 7d2ed9ac "NFSv4: parse and display server
implementation ids," Fri Feb 17, 2012.

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

NFS: Use proper naming conventions for NFSv4.1 server scope fields

Clean up: When naming fields and data types, follow established
conventions to facilitate accurate grep/cscope searches.

Additionally, for consistency, move the scope field into the NFSv4-
specific part of the nfs_client, and free that memory in the logic
that shuts down NFSv4 nfs_clients.

Introduced by commit 99fe60d0 "nfs41: exchange_id operation", April
1 2009.

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

NFSv4.1 data server timeo and retrans module parameters

Set the recovery parameters for data servers.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Make v2 configurable

With this patch NFS v2 can be disabled during Kconfig. I default the
option to "y" to match the current behavior.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv2/v3: Simulate the change attribute

Use the ctime to simulate a change attribute for NFSv2 and NFSv3.

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

NFS: Honor the authflavor set in the clone mount data

The authflavor is set in an nfs_clone_mount structure and passed to the
xdev_mount() functions where it was promptly ignored. Instead, use it
to initialize an rpc_clnt for the cloned server.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Remove all #inclusions of asm/system.h

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it. Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`

Signed-off-by: David Howells <dhowells@redhat.com>

NFS: Only define some function when v4.1 is enabled

Now that the nfs4_cb_match_client() function is static, gcc notices that
it is only used when CONFIG_NFS_V4_1 is enabled.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Fix a number of sparse warnings

Fix a number of "warning: symbol 'foo' was not declared. Should it be
static?" conditions.

Fix 2 cases of "warning: Using plain integer as NULL pointer"

fs/nfs/delegation.c:263:31: warning: restricted fmode_t degrades to integer
- We want to allow upgrades to a WRITE delegation, but should otherwise
consider servers that hand out duplicate delegations to be borken.

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

NFS: Make clientaddr= optional

For NFSv4 mounts, the clientaddr= mount option has always been
required. Now we have rpc_localaddr() in the kernel, which was
modeled after the same logic in the mount.nfs command that constructs
the clientaddr= mount option. If user space doesn't provide a
clientaddr= mount option, the kernel can now construct its own.

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

SUNRPC: Use RCU to dereference the rpc_clnt.cl_xprt field

A migration event will replace the rpc_xprt used by an rpc_clnt. To
ensure this can be done safely, all references to cl_xprt must now use
a form of rcu_dereference().

Special care is taken with rpc_peeraddr2str(), which returns a pointer
to memory whose lifetime is the same as the rpc_xprt.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[ cel: fix lockdep splats and layering violations ]
[ cel: forward ported to 3.4 ]
[ cel: remove rpc_max_reqs(), add rpc_net_ns() ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4: parse and display server implementation ids

Shows the implementation ids in /proc/self/mountstats. This doesn't break
the nfs-utils mountstats tool.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: Don't call nfs4_deviceid_purge_client() unless we're NFSv4.1

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

NFS: Ensure struct nfs_client holds a reference to the net namespace

Otherwise we have no guarantee that the net namespace won't just
disappear from underneath us once the task that created it
is destroyed.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>

NFS: fix nfs4_find_client_sessionid() arguments list

It's not compilable in case of CONFIG_NFS_V4_1 is not set.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Initialise the nfs_net->nfs_client_lock

Ensure that we initialise the nfs_net->nfs_client_lock spinlock.
Also ensure that nfs_server_remove_lists() doesn't try to
dereference server->nfs_client before that is initialised.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>

LockD: make nlm hosts network namespace aware

This object depends on RPC client, and thus on network namespace.
So let's make it's allocation and lookup in network namespace context.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

security: trim security.h

Trim security.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>

NFS: search for client session id in proper network namespace

Network namespace is taken from request transport and passed as a part of
cb_process_state structure.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: make nfs_client_lock per net ns

This patch makes nfs_clients_lock allocated per network namespace. All items it
protects are already network namespace aware.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: make cb_ident_idr per net ns

This patch makes ID's infrastructure network namespace aware. This was done
mainly because of nfs_client_lock, which is desired to be per network
namespace, but protects NFS clients ID's.

NOTE: NFS client's net pointer have to be set prior to ID initialization,
proper assignment was moved.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: make nfs_volume_list per net ns

This patch splits global list of NFS servers into per-net-ns array of lists.
This looks more strict and clearer.
BTW, this patch also makes "/proc/fs/nfsfs/volumes" content depends on /proc
mount owner pid namespace. See below for details.

NOTE: few words about how was /proc/fs/nfsfs/ entries content show per network
namespace done. This is a little bit tricky and not the best is could be. But
it's cheap (proper fix for /proc conteinerization is a hard nut to crack).
The idea is simple: take proper network namespace from pid namespace
child reaper nsproxy of /proc/ mount creator.
This actually means, that if there are 2 containers with different net
namespace sharing pid namespace, then read of /proc/fs/nfsfs/ entries will
always return content, taken from net namespace of pid namespace creator task
(and thus second namespace set wil be unvisible).

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: make nfs_client_list per net ns

This patch splits global list of NFS clients into per-net-ns array of lists.
This looks more strict and clearer.
BTW, this patch also makes "/proc/fs/nfsfs/servers" entry content depends on
/proc mount owner pid namespace. See below for details.

NOTE: few words about how was /proc/fs/nfsfs/ entries content show per network
namespace done. This is a little bit tricky and not the best is could be. But
it's cheap (proper fix for /proc conteinerization is a hard nut to crack).
The idea is simple: take proper network namespace from pid namespace
child reaper nsproxy of /proc/ mount creator.
This actually means, that if there are 2 containers with different net
namespace sharing pid namespace, then read of /proc/fs/nfsfs/ entries will
always return content, taken from net namespace of pid namespace creator task
(and thus second namespace set wil be unvisible).

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

SUNRPC: constify the rpc_program

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

NFS: remove unused nfs4_find_client_no_ident function

Looks like this function survived after some cleanup patch without a reason.
Now it's not called or referenced and I believe, that it can be simply removed.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4: Replace lock_owner->ld_id with an ida based allocator

Again, We're unlikely to ever need more than 2^31 simultaneous lock
owners, so let's replace the custom allocator.

Now that there are no more users, we can also get rid of the custom
allocator code.

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

NFSv4: Replace state_owner->so_owner_id with an ida based allocator

We're unlikely to ever need more than 2^31 simultaneous open owners,
so let's replace the custom allocator with the generic ida allocator.

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

NFS: idmap PipeFS notifier introduced

v2:
1) Added "nfs_idmap_init" and "nfs_idmap_quit" definitions for kernels built
without CONFIG_NFS_V4 option set.

This patch subscribes NFS clients to RPC pipefs notifications. Idmap notifier
is registering on NFS module load. This notifier callback is responsible for
creation/destruction of PipeFS idmap pipe dentry for NFS4 clients.

Since ipdmap pipe is created in rpc client pipefs directory, we have make sure,
that this directory has been created already. IOW RPC client notifier callback
has been called already. To achive this, PipeFS notifier priorities has been
introduced (RPC clients notifier priority is greater than NFS idmap one).
But this approach gives another problem: unlink for RPC client directory will
be called before NFS idmap pipe unlink on UMOUNT event and will fail, because
directory is not empty.
The solution, introduced in this patch, is to try to remove client directory
once again after idmap pipe was unlinked. This looks like ugly hack, so
probably it should be replaced in some more elegant way.

Note that no locking required in notifier callback because PipeFS superblock
pointer is passed as an argument from it's creation or destruction routine and
thus we can be sure about it's validity.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: pass NFS client owner network namespace to RPC client creation routine

This patch replaces static "init_net" with nfs_client->net pointer in RPC
client creation calls.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: make NFS client allocated per network namespace context

This patch adds new net variable to nfs_client structure. This variable is set
on NFS client creation and cheched during matching NFS client search.
Initially current->nsproxy->net_ns is used as network namespace owner for new
NFS client to create. This network namespace pointer is set during mount
options parsing and thus can be passed from user-spave utils in future if will
be necessary.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

module_param: make bool parameters really bool (drivers & misc)

module_param(bool) used to counter-intuitively take an int. In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option. For this version
it'll simply give a warning, but it'll break next kernel version.

Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

NFSv4: Change the default setting of the nfs4_disable_idmapping parameter

Now that the use of numeric uids/gids is officially sanctioned in
RFC3530bis, it is time to change the default here to 'enabled'.

By doing so, we ensure that NFSv4 copies the behaviour of NFSv3 when we're
using the default AUTH_SYS authentication (i.e. when the client uses the
numeric uids/gids as authentication tokens), so that when new files are
created, they will appear to have the correct user/group.
It also fixes a number of backward compatibility issues when migrating
from NFSv3 to NFSv4 on a platform where the server uses different uid/gid
mappings than the client.

Note also that this setting has been successfully tested against servers
that do not support numeric uids/gids at several Connectathon/Bakeathon
events at this point, and the fall back to using string names/groups has
been shown to work well in all those test cases.

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

NFS: Cache state owners after files are closed

Servers have a finite amount of memory to store NFSv4 open and lock
owners. Moreover, servers may have a difficult time determining when
they can reap their state owner table, thanks to gray areas in the
NFSv4 protocol specification. Thus clients should be careful to reuse
state owners when possible.

Currently Linux is not too careful. When a user has closed all her
files on one mount point, the state owner's reference count goes to
zero, and it is released. The next OPEN allocates a new one. A
workload that serially opens and closes files can run through a large
number of open owners this way.

When a state owner's reference count goes to zero, slap it onto a free
list for that nfs_server, with an expiry time. Garbage collect before
looking for a state owner. This makes state owners for active users
available for re-use.

Now that there can be unused state owners remaining at umount time,
purge the state owner free list when a server is destroyed. Also be
sure not to reclaim unused state owners during state recovery.

This change has benefits for the client as well. For some workloads,
this approach drops the number of OPEN_CONFIRM calls from the same as
the number of OPEN calls, down to just one. This reduces wire traffic
and thus open(2) latency. Before this patch, untarring a kernel
source tarball shows the OPEN_CONFIRM call counter steadily increasing
through the test. With the patch, the OPEN_CONFIRM count remains at 1
throughout the entire untar.

As long as the expiry time is kept short, I don't think garbage
collection should be terribly expensive, although it does bounce the
clp->cl_lock around a bit.

[ At some point we should rationalize the use of the nfs_server
->destroy method. ]

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[Trond: Fixed a garbage collection race and a few efficiency issues]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

SUNRPC: Clean up the RPCSEC_GSS service ticket requests

Instead of hacking specific service names into gss_encode_v1_msg, we should
just allow the caller to specify the service name explicitly.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>

Check validity of cl_rpcclient in nfs_server_list_show

As soon as the nfs_client gets created, its cl_rpcclient is set to
ERR_PTR(-EINVAL). The rpc client structure is allocated later. Check
if the client is ready before using the cl_rpcclient pointer.

Signed-off-by: Malahal Naineni <malahal@us.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs: fix bug about IPv6 address scope checking

The result from ipv6_addr_scope() always not be a single SCOPE,
so we can't use equal to compare the result with IPV6_ADDR_SCOPE_LINKLOCAL
at nfs_sockaddr_match_ipaddr6.

This patch fixs the problem, and lets checking address before scope_id.

Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs: fix bug about IPv6 address scope checking

The result from ipv6_addr_scope() is a set of flags, not a single value,
so we can't just compare the result with IPV6_ADDR_SCOPE_LINKLOCAL.

This patch fixs the problem, and checks for unequal addresses before
scope_id.

Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

pnfsblock: add device operations

Signed-off-by: Jim Rees <rees@umich.edu>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
[upcall bugfixes]
Signed-off-by: Peng Tao <peng_tao@emc.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

pnfs: ask for layout_blksize and save it in nfs_server

Block layout needs it to determine IO size.

Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Tao Guo <glorioustao@gmail.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Jim Rees <rees@umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

pnfs: add set-clear layoutdriver interface

To allow layout driver to issue getdevicelist at mount time, and clean up
at umount time.

[fixup non NFS_V4_1 set_pnfs_layoutdriver definition]
[pnfs: pass mntfh down the init_pnfs path]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Jim Rees <rees@umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Convert nfs4_set_ds_client to EXPORT_SYMBOL_GPL

This is not part of an external ABI...

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

NFS: move pnfs layouts to nfs_server structure

Layouts should be tracked per nfs_server (aka superblock)
instead of per struct nfs_client, which may have multiple FSIDs associated
with it.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: use scope from exchange_id to skip reclaim

can be skipped if the "eir_server_scope" from the exchange_id proc differs from
previous calls.

Also, in the future server_scope will be useful for determining whether client
trunking is available

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: purge deviceid cache on nfs_free_client

Use the pnfs_layoutdriver_type both as a qualifier for the deviceid,
distinguishing deviceid from different layout types on the server,
and for freeing the layout-driver allocated structure containing the
nfs4_deviceid_node.

[BUG in _deviceid_purge_client]
[layout_driver MUST set free_deviceid_node if using dev-cache]
[let ver < 4.1 compile]
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
[removed EXPORT_SYMBOL_GPL(nfs4_deviceid_purge_client)]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

NFSv4: Send unmapped uid/gids to the server when using auth_sys

The new behaviour is enabled using the new module parameter
'nfs4_disable_idmapping'.

Note that if the server rejects an unmapped uid or gid, then
the client will automatically switch back to using the idmapper.

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

NFSv4.1: data server connection

Introduce a data server set_client and init session following the
nfs4_set_client and nfs4_init_session convention.

Once a new nfs_client is on the nfs_client_list, the nfs_client cl_cons_state
serializes access to creating an nfs_client struct with matching properties.

Use the new nfs_get_client() that initializes new clients.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: add MDS mount DS only check

The DS only role cannot be used to mount.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: new flag for lease time check

Data servers cannot send nfs4_proc_get_lease_time. but still need to setup
state renewal. Add the NFS_CS_CHECK_LEASE_TIME bit to indicate if the lease
time can be checked.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: new flag for state renewal check

Data servers not sharing a session with the mount MDS always have an empty
cl_superblocks list.
Replace the cl_superblocks empty list check to see if it is time to shut down
renewd with the NFS_CS_STOP_RENEW bit which is not set by such a data server.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS move nfs_client initialization into nfs_get_client

Now nfs_get_client returns an nfs_client ready to be used no matter if it was
found or created.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS do not find client in NFSv4 pg_authenticate

The information required to find the nfs_client cooresponding to the incoming
back channel request is contained in the NFS layer. Perform minimal checking
in the RPC layer pg_authenticate method, and push more detailed checking into
the NFS layer where the nfs_client can be found.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Move cl_delegations to the nfs_server struct

Delegations are per-inode, not per-nfs_client. When a server file
system is migrated, delegations on the client must be moved from the
source to the destination nfs_server. Make it easier to manage a
mount point's delegation list across a migration event by moving the
list to the nfs_server struct.

Clean up: I added documenting comments to public functions I changed
in this patch. For consistency I added comments to all the other
public functions in fs/nfs/delegation.c.

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

NFS: Allow walking nfs_client.cl_superblocks list outside client.c

We're about to move some fields from struct nfs_client to struct
nfs_server. There is a many-to-one relationship between nfs_servers
and nfs_clients. After these fields are moved to the nfs_server
struct, to visit all of the data in these fields that is owned by one
nfs_client, code will need to visit each nfs_server on the
cl_superblocks list for that nfs_client.

To serialize changes to the cl_superblocks list during these little
expeditions, protect the list with RCU.

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

pnfs: layout roc code

A layout can request return-on-close. How this interacts with the
forgetful model of never sending LAYOUTRETURNS is a bit ambiguous.
We forget any layouts marked roc, and wait for them to be completely
forgotten before continuing with the close. In addition, to compensate
for races with any inflight LAYOUTGETs, and the fact that we do not get
any layout stateid back from the server, we set the barrier to the worst
case scenario of current_seqid + number of outstanding LAYOUTGETS.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS refactor nfs_find_client and reference client across callback processing

Fixes a bug where the nfs_client could be freed during callback processing.
Refactor nfs_find_client to use minorversion specific means to locate the
correct nfs_client structure.

In the NFS layer, V4.0 clients are found using the callback_ident field in the
CB_COMPOUND header. V4.1 clients are found using the sessionID in the
CB_SEQUENCE operation which is also compared against the sessionID associated
with the back channel thread after a successful CREATE_SESSION.

Each of these methods finds the one an only nfs_client associated
with the incoming callback request - so nfs_find_client_next is not needed.

In the RPC layer, the pg_authenticate call needs to find the nfs_client. For
the v4.0 callback service, the callback identifier has not been decoded so a
search by address, version, and minorversion is used. The sessionid for the
sessions based callback service has (usually) not been set for the
pg_authenticate on a CB_NULL call which can be sent prior to the return
of a CREATE_SESSION call, so the sessionid associated with the back channel
thread is not used to find the client in pg_authenticate for CB_NULL calls.

Pass the referenced nfs_client to each CB_COMPOUND operation being proceesed
via the new cb_process_state structure. The reference is held across
cb_compound processing.

Use the new cb_process_state struct to move the NFS4ERR_RETRY_UNCACHED_REP
processing from process_op into nfs4_callback_sequence where it belongs.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS implement v4.0 callback_ident

Use the small id to pointer translator service to provide a unique callback
identifier per SETCLIENTID call used to identify the v4.0 callback service
associated with the clientid.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS do not clear minor version at nfs_client free

Resetting the client minor version operations causes nfs4_destroy_callback
to fail to shutdown the NFSv4.1 callback service.

There is no reason to reset the client minorversion operations when the
nfs_client struct is being freed.

Remove the minorverion reset and rename the function.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: pnfs: filelayout: add driver's LAYOUTGET and GETDEVICEINFO infrastructure

Implement the driver's io_ops->alloc_lseg and free_lseg functions,
which integrate into the deviceid cache and calls out to
nfs4_proc_getdeviceinfo when necessary.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Dean Hildebrand <dhildebz@umich.edu>
Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: Mike Sager <sager@netapp.com>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: client needs to maintain list of inodes with active layouts

In particular, server reboot will invalidate all layouts.

Note that in order to have an active layout, we must get a successful response
from the server. To avoid adding that machinery, this patch just includes a
stub that fakes up a successful return. Since the layout is never referenced
for io, this is not a problem.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Dean Hildebrand <dhildebz@umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: set layout driver

Put in the infrastructure that uses information returned from the
server at mount to select a layout driver module.

In this patch, a stub is used that always returns "no driver found".

Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Dean Hildebrand <dhildebz@umich.edu>
Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Revalidate caches on lock

Instead of blindly zapping the caches, attempt to revalidate them if
the server has indicated that it uses high resolution timestamps.

NFSv4 should be able to always revalidate the cache since the
protocol requires the update of the change attribute on modification of
the data. In reality, there are servers (the Linux NFS server
for example) that do not obey this requirement and use ctime as the
basis for change attribute. Long term, the server needs to be fixed.
At this time, and to be on the safe side, continue zapping caches if
the server indicates that it does not have a high resolution timestamp.

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

NFS: Readdir plus in v4

By requsting more attributes during a readdir, we can mimic the readdir plus
operation that was in NFSv3.

To test, I ran the command `ls -lU --color=none` on directories with various
numbers of files. Without readdir plus, I see this:

n files | 100 | 1,000 | 10,000 | 100,000 | 1,000,000
--------+-----------+-----------+-----------+-----------+----------
real | 0m00.153s | 0m00.589s | 0m05.601s | 0m56.691s | 9m59.128s
user | 0m00.007s | 0m00.007s | 0m00.077s | 0m00.703s | 0m06.800s
sys | 0m00.010s | 0m00.070s | 0m00.633s | 0m06.423s | 1m10.005s
access | 3 | 1 | 1 | 4 | 31
getattr | 2 | 1 | 1 | 1 | 1
lookup | 104 | 1,003 | 10,003 | 100,003 | 1,000,003
readdir | 2 | 16 | 158 | 1,575 | 15,749
total | 111 | 1,021 | 10,163 | 101,583 | 1,015,784

With readdir plus enabled, I see this:

n files | 100 | 1,000 | 10,000 | 100,000 | 1,000,000
--------+-----------+-----------+-----------+-----------+----------
real | 0m00.115s | 0m00.206s | 0m01.079s | 0m12.521s | 2m07.528s
user | 0m00.003s | 0m00.003s | 0m00.040s | 0m00.290s | 0m03.296s
sys | 0m00.007s | 0m00.020s | 0m00.120s | 0m01.357s | 0m17.556s
access | 3 | 1 | 1 | 1 | 7
getattr | 2 | 1 | 1 | 1 | 1
lookup | 4 | 3 | 3 | 3 | 3
readdir | 6 | 62 | 630 | 6,300 | 62,993
total | 15 | 67 | 635 | 6,305 | 63,004

Readdir plus disabled has about a 16x increase in the number of rpc calls and
is 4 - 5 times slower on large directories.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: readdir with vmapped pages

We can use vmapped pages to read more information from the network at once.
This will reduce the number of calls needed to complete a readdir.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
[trondmy: Added #include for linux/vmalloc.h> in fs/nfs/dir.c]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

sunrpc: Add net to rpc_create_args

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfs: introduce mount option '-olocal_lock' to make locks local

NFS clients since 2.6.12 support flock locks by emulating fcntl byte-range
locks. Due to this, some windows applications which seem to use both flock
(share mode lock mapped as flock by Samba) and fcntl locks sequentially on
the same file, can't lock as they falsely assume the file is already locked.
The problem was reported on a setup with windows clients accessing excel files
on a Samba exported share which is originally a NFS mount from a NetApp filer.

Older NFS clients (< 2.6.12) did not see this problem as flock locks were
considered local. To support legacy flock behavior, this patch adds a mount
option "-olocal_lock=" which can take the following values:

'none' - Neither flock locks nor POSIX locks are local
'flock' - flock locks are local
'posix' - fcntl/POSIX locks are local
'all' - Both flock locks and POSIX locks are local

Testing:

- This patch was tested by using -olocal_lock option with different values
and the NLM calls were noted from the network packet captured.

'none' - NLM calls were seen during both flock() and fcntl(), flock lock
was granted, fcntl was denied
'flock' - no NLM calls for flock(), NLM call was seen for fcntl(),
granted
'posix' - NLM call was seen for flock() - granted, no NLM call for fcntl()
'all' - no NLM calls were seen during both flock() and fcntl()

- No bugs were seen during NFSv4 locking/unlocking in general and NFSv4
reboot recovery.

Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Fix a typo in nfs_sockaddr_match_ipaddr6

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

NFSv41: Cleanup for nfs4_alloc_session.

There is no reason to change the nfs_client state every time we allocate a
new session. Move that line into nfs4_init_client_minor_version.

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

NFSv41: Clean up the NFSv4.1 minor version specific operations

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

NFSv4.1: Ensure that we initialise the session when following a referral

Put the code that is common to both the referral and ordinary mount cases
into a common helper routine.

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

NFS: Reduce the stack footprint of nfs_create_server

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

NFSv4: Eliminate nfs4_path_walk()

All we really want is the ability to retrieve the root file handle. We no
longer need the ability to walk down the path, since that is now done in
nfs_follow_remote_path().

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

NFS: rsize and wsize settings ignored on v4 mounts

NFSv4 mounts ignore the rsize and wsize mount options, and always use
the default transfer size for both. This seems to be because all
NFSv4 mounts are now cloned, and the cloning logic doesn't copy the
rsize and wsize settings from the parent nfs_server.

I tested Fedora's 2.6.32.11-99 and it seems to have this problem as
well, so I'm guessing that .33, .32, and perhaps older kernels have
this issue as well.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Stable <stable@kernel.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4: fix delegated locking

Arnaud Giersch reports that NFSv4 locking is broken when we hold a
delegation since commit 8e469ebd6dc32cbaf620e134d79f740bf0ebab79 (NFSv4:
Don't allow posix locking against servers that don't support it).

According to Arnaud, the lock succeeds the first time he opens the file
(since we cannot do a delegated open) but then fails after we start using
delegated opens.

The following patch fixes it by ensuring that locking behaviour is
governed by a per-filesystem capability flag that is initially set, but
gets cleared if the server ever returns an OPEN without the
NFS4_OPEN_RESULT_LOCKTYPE_POSIX flag being set.

Reported-by: Arnaud Giersch <arnaud.giersch@iut-bm.univ-fcomte.fr>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

nfs: kill renewd before clearing client minor version

renewd should be synchronously killed before we destroy the session in
nfs4_clear_minor_version

Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
[Trond.Myklebust@netapp.com: clean up to remove 'unused function
warning when !CONFIG_NFS_V4]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: V2 adjust max_rqst_sz, max_resp_sz w.r.t to rsize, wsize

The v4.1 client should take into account the desired rsize, wsize when
negotiating the max size in CREATE_SESSION. Accordingly, it should use
rsize, wsize that are smaller than the session negotiated values.

Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs: Avoid overrun when copying client IP address string

As seen in <http://bugs.debian.org/549002>, nfs4_init_client() can
overrun the source string when copying the client IP address from
nfs_parsed_mount_data::client_address to nfs_client::cl_ipaddr. Since
these are both treated as null-terminated strings elsewhere, the copy
should be done with strlcpy() not memcpy().

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Propagate 'fsc' mount option through automounts

Propagate the NFS 'fsc' mount option through NFS automounts of various types.

This is now required as commit:

commit c02d7adf8c5429727a98bad1d039bccad4c61c50
Author: Trond Myklebust <Trond.Myklebust@netapp.com>
Date: Mon Jun 22 15:09:14 2009 -0400

NFSv4: Replace nfs4_path_walk() with VFS path lookup in a private namespace

uses VFS-driven automounting to reach all submounts barring the root, thus
preventing fscaching from being enabled on any submount other than the root.

This patch gets around that by propagating the NFS_OPTION_FSCACHE flag across
automounts. If a uniquifier is supplied to a mount then this is propagated to
all automounts of that mount too.

Signed-off-by: David Howells <dhowells@redhat.com>
[Trond: Fixed up the definition of nfs_fscache_get_super_cookie for the
case of #undef CONFIG_NFS_FSCACHE]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Get rid of the NFS_MOUNT_VER3 and NFS_MOUNT_TCP flags

Keep it in the case of the legacy binary mount interface, but purge it from
the nfs_server structure.

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

seq_file: constify seq_operations

Make all seq_operations structs const, to help mitigate against
revectoring user-triggerable function pointers.

This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nfs: initialize the backing_dev_info when creating the server

NFS may free the server structure without ever having used the
bdi, so we either need to flag the bdi as being uninitialized or
initialize it up front. This does the latter.

This fixes a crash with mounting more than one NFS file system,
should people ever need that kind of obscure NFS functionality.

Tested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

writeback: add name to backing_dev_info

This enables us to track who does what and print info. Its main use
is catching dirty inodes on the default_backing_dev_info, so we can
fix that up.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

nfs: remove superfluous BUG_ON()s
Subject: [PATCH] nfs: remove superfluous BUG_ON()s

Remove duplicated BUG_ON()s from nfs[4]_create_server()
(we make the same checks earlier in both functions).

This takes care of the following entries from Dan's list:

fs/nfs/client.c +1078 nfs_create_server(47) warning: variable derefenced before check 'server->nfs_client'
fs/nfs/client.c +1079 nfs_create_server(48) warning: variable derefenced before check 'server->nfs_client->rpc_ops'
fs/nfs/client.c +1363 nfs4_create_server(43) warning: variable derefenced before check 'server->nfs_client'
fs/nfs/client.c +1364 nfs4_create_server(44) warning: variable derefenced before check 'server->nfs_

Reported-by: Dan Carpenter <error27@gmail.com>
Cc: corbet@lwn.net
Cc: eteo@redhat.com
Cc: Julia Lawall <julia@diku.dk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4: Add 'server capability' flags for NFSv4 recommended attributes

If the NFSv4 server doesn't support a POSIX attribute, the generic NFS code
needs to know that, so that it don't keep trying to poll for it.

However, by the same count, if the NFSv4 server does support that
attribute, then we should ensure that the inode metadata is appropriately
labelled as being untrusted. For instance, if we don't know the correct
value of the file's uid, we should certainly not be caching ACLs or ACCESS
results.

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

NFSv4: Fix an NFSv4 mount regression

Commit 008f55d0e019943323c20a03493a2ba5672a4cc8 (nfs41: recover lease in
_nfs4_lookup_root) forces the state manager to always run on mount. This is
a bug in the case of NFSv4.0, which doesn't require us to send a
setclientid until we want to grab file state.

In any case, this is completely the wrong place to be doing state
management. Moving that code into nfs4_init_session...

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

NFS: Return error code from nfs_callback_up() to user space

If the kernel cannot start the NFSv4 callback service during a mount
request, it returns -ENOMEM to user space, resulting in this message:

mount.nfs4: Cannot allocate memory

Adjust nfs_alloc_client() and nfs_get_client() to pass NFSv4 callback
start-up errors back to user space so a less mysterious error message
can be displayed by the mount command.

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

nfs41: Setup the backchannel

The NFS v4.1 callback service has already been setup, and
rpc_xprt->serv points to the svc_serv structure describing it.
Invoke the xprt_setup_backchannel() initialization to pre-
allocate the necessary backchannel structures.

Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: change nfs4_put_session(nfs4_session**) to nfs4_destroy_session(nfs_session*)]
Signed-off-by: Alexandros Batsakis <Alexandros.Batsakis@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[moved xprt_setup_backchannel from nfs4_init_session to nfs4_init_backchannel]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

nfs41: Allow NFSv4 and NFSv4.1 callback services to coexist

Tracks the nfs_callback_info for both versions, enabling the callback
service for v4 and v4.1 to run concurrently and be stopped independently
of each other.

Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

nfs41: minorversion support for nfs4_{init,destroy}_callback

move nfs4_init_callback into nfs4_init_client_minor_version
and nfs4_destroy_callback into nfs4_clear_client_minor_version

as these need to happen also when auto-negotiating the minorversion
once the callback service for nfs41 becomes different than for nfs4.0

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Fix checkpatch warning]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Type check arguments of nfs_callback_up]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Backchannel: Remove FIXME comment]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

nfs41: Refactor nfs4_{init,destroy}_callback for nfs4.0

Refactor-out code to bring the callback service up and down.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>

nfs41: recover lease in _nfs4_lookup_root

This creates the nfsv4.1 session on mount.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: add session setup to the state manager

At mount, nfs_alloc_client sets the cl_state NFS4CLNT_LEASE_EXPIRED bit
and nfs4_alloc_session sets the NFS4CLNT_SESSION_SETUP bit, so both bits are
set when nfs4_lookup_root calls nfs4_recover_expired_lease which schedules
the nfs4_state_manager and waits for it to complete.

Place the session setup after the clientid establishment in nfs4_state_manager
so that the session is setup right after the clientid has been established
without rescheduling the state manager.

Unlike nfsv4.0, the nfs_client struct is not ready to use until the session
has been established. Postpone marking the nfs_client struct to NFS_CS_READY
until after a successful CREATE_SESSION call so that other threads cannot use
the client until the session is established.

If the EXCHANGE_ID call fails and the session has not been setup (the
NFS4CLNT_SESSION_SETUP bit is set), mark the client with the error and return.

If the session setup CREATE_SESSION call fails with NFS4ERR_STALE_CLIENTID
which could occur due to server reboot or network partition inbetween the
EXCHANGE_ID and CREATE_SESSION call, reset the NFS4CLNT_LEASE_EXPIRED and
NFS4CLNT_SESSION_SETUP bits and try again.

If the CREATE_SESSION call fails with other errors, mark the client with
the error and return.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

[nfs41: NFS_CS_SESSION_SETUP cl_cons_state for back channel setup]
On session setup, the CREATE_SESSION reply races with the server back channel
probe which needs to succeed to setup the back channel. Set a new
cl_cons_state NFS_CS_SESSION_SETUP just prior to the CREATE_SESSION call
and add it as a valid state to nfs_find_client so that the client back channel
can find the nfs_client struct and won't drop the server backchannel probe.
Use a new cl_cons_state so that NFSv4.0 back channel behaviour which only
sets NFS_CS_READY is unchanged.
Adjust waiting on the nfs_client_active_wq accordingly.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

[nfs41: rename NFS_CS_SESSION_SETUP to NFS_CS_SESSION_INITING]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: set NFS_CL_SESSION_INITING in alloc_session]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: move session setup into a function]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[moved nfs4_proc_create_session declaration here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: use session attributes for rsize and wsize

Set the mount points rsize and wsize to the negotiated session fore channel
maximum response and requeset size. These values will be bound checked in
nfs_server_set_fsinfo.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[move nfs4_session_set_rwsize into CONFIG_NFS_V4]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: introduce nfs4_call_sync

Use nfs4_call_sync rather than rpc_call_sync to provide
for a nfs41 sessions-enabled interface for sessions manipulation.

The nfs41 rpc logic uses the rpc_call_prepare method to
recover and create the session, as well as selecting a free slot id
and the rpc_call_done to free the slot and update slot table
related metadata.

In the coming patches we'll add rpc prepare and done routines
for setting up the sequence op and processing the sequence result.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_call_sync]
As per 11-14-08 review.
Squash into "nfs41: introduce nfs4_call_sync" and "nfs41: nfs4_setup_sequence"
Define two functions one for v4 and one for v41
add a pointer to struct nfs4_client to the correct one.
Signed-off-by: Andy Adamson <andros@netapp.com>
[added BUG() in _nfs4_call_sync_session if !CONFIG_NFS_V4_1]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: check for session not minorversion]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[group minorversion specific stuff together]
Signed-off-by: Alexandros Batsakis <Alexandros.Batsakis@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: fixup nfs4_clear_client_minor_version]
[introduce nfs4_init_client_minor_version() in this patch]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[cleaned-up patch: got rid of nfs_call_sync_t, dprintks, cosmetics, extra server defs]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: sessions client infrastructure

NFSv4.1 Sessions basic data types, initialization, and destruction.

The session is always associated with a struct nfs_client that holds
the exchange_id results.

Signed-off-by: Rahul Iyer <iyer@netapp.com>
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[remove extraneous rpc_clnt pointer, use the struct nfs_client cl_rpcclient.
remove the rpc_clnt parameter from nfs4 nfs4_init_session]
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Use the presence of a session to determine behaviour instead of the
minorversion number.]
Signed-off-by: Andy Adamson <andros@netapp.com>
[constified nfs4_has_session's struct nfs_client parameter]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Rename nfs4_put_session() to nfs4_destroy_session() and call it from nfs4_free_client() not nfs4_free_server().
Also get rid of nfs4_get_session() and the ref_count in nfs4_session struct as keeping track of nfs_client should be sufficient]
Signed-off-by: Alexandros Batsakis <Alexandros.Batsakis@netapp.com>
[nfs41: pass rsize and wsize into nfs4_init_session]
Signed-off-by: Andy Adamson <andros@netapp.com>
[separated out removal of rpc_clnt parameter from nfs4_init_session ot a
patch of its own]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Pass the nfs_client pointer into nfs4_alloc_session]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: don't assign to session->clp->cl_session in nfs4_destroy_session]
[nfs41: fixup nfs4_clear_client_minor_version]
[introduce nfs4_clear_client_minor_version() in this patch]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Refactor nfs4_init_session]
Moved session allocation into nfs4_init_client_minor_version, called from
nfs4_init_client.
Leave rwise and wsize initialization in nfs4_init_session, called from
nfs4_init_server.
Reverted moving of nfs_fsid definition to nfs_fs_sb.h
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Move NFS4_MAX_SLOT_TABLE define from under CONFIG_NFS_V4_1]
[Fix comile error when CONFIG_NFS_V4_1 is not set.]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[moved nfs4_init_slot_table definition to "create_session operation"]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: alloc session with GFP_KERNEL]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: Use mount minorversion option

Use the mount minorversion option to initialize the nfs_client cl_minorversion
and match it in nfs_match_client() when looking up a nfs_client.

[nfs41: remove ifdefs around nfs_client_initdata.minorversion]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: nfs_client.cl_minorversion

This field is set to the nfsv4 minor version for this mount.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>

Note: This patch sets the referral to the same minorversion as the
current mount. Revisit in future patch.

Signed-off-by: Andy Adamson <andros@netapp.com>
[removed cl_minorversion assignment in nfs_set_client]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[always define nfs_client.cl_minorversion]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Add mount options to enable local caching on NFS

Add NFS mount options to allow the local caching support to be enabled.

The attached patch makes it possible for the NFS filesystem to be told to make
use of the network filesystem local caching service (FS-Cache).

To be able to use this, a recent nfsutils package is required.

There are three variant NFS mount options that can be added to a mount command
to control caching for a mount. Only the last one specified takes effect:

(*) Adding "fsc" will request caching.

(*) Adding "fsc=<string>" will request caching and also specify a uniquifier.

(*) Adding "nofsc" will disable caching.

For example:

mount warthog:/ /a -o fsc

The cache of a particular superblock (NFS FSID) will be shared between all
mounts of that volume, provided they have the same connection parameters and
are not marked 'nosharecache'.

Where it is otherwise impossible to distinguish superblocks because all the
parameters are identical, but the 'nosharecache' option is supplied, a
uniquifying string must be supplied, else only the first mount will be
permitted to use the cache.

If there's a key collision, then the second mount will disable caching and give
a warning into the kernel log.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>

NFS: Display local caching state

Display the local caching state in /proc/fs/nfsfs/volumes.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>

NFS: Define and create server-level objects

Define and create server-level cache index objects (as managed by nfs_client
structs).

Each server object is created in the NFS top-level index object and is itself
an index into which superblock-level objects are inserted.

Ideally there would be one superblock-level object per server, and the former
would be folded into the latter; however, since the "nosharecache" option
exists this isn't possible.

The server object key is a sequence consisting of:

(1) NFS version

(2) Server address family (eg: AF_INET or AF_INET6)

(3) Server port.

(4) Server IP address.

The key blob is of variable length, depending on the length of (4).

The server object is given no coherency data to carry in the auxiliary data
permitted by the cache.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>

proc 2/2: remove struct proc_dir_entry::owner

Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.

We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.

But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.

->read_proc/->write_proc were just fixed to not require ->owner for
protection.

rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.

Removing ->owner will also make PDE smaller.

So, let's nuke it.

Kudos to Jeff Layton for reminding about this, let's say, oversight.

http://bugzilla.kernel.org/show_bug.cgi?id=12454

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

NFS: Simplify logic to compare socket addresses in client.c

Callback requests from IPv4 servers are now always guaranteed to be
AF_INET, and never mapped IPv4 AF_INET6 addresses. Both
nfs_match_client() and nfs_find_client() can now share the same
address comparison logic, so fold them together.

We can also dispense with of most of the conditional compilation
in here.

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

NFS: Fix the fix to Bugzilla #11061, when IPv6 isn't defined...

Stephen Rothwell reports:

Today's linux-next build (powerpc ppc64_defconfig) failed like this:

fs/built-in.o: In function `.nfs_get_client':
client.c:(.text+0x115010): undefined reference to `.__ipv6_addr_type'

Fix by moving the IPV6 specific parts of commit
d7371c41b0cda782256b1df759df4e8d4724584c ("Bug 11061, NFS mounts dropped")
into the '#ifdef IPV6..." section.

Also fix up a couple of formatting issues.

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

Bug 11061, NFS mounts dropped

Addresses: http://bugzilla.kernel.org/show_bug.cgi?id=11061

sockaddr structures can't be reliably compared using memcmp() because
there are padding bytes in the structure which can't be guaranteed to
be the same even when the sockaddr structures refer to the same
socket. Instead compare all the relevant fields. In the case of IPv6
sin6_flowinfo is not compared because it only affects QoS and
sin6_scope_id is only compared if the address is "link local" because
"link local" addresses need only be unique to a specific link.

Signed-off-by: Ian Dall <ian@beware.dropbear.id.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4: Fix up delegation callbacks

Currently, the callback server is listening on IPv6 if it is enabled. This
means that IPv4 addresses will always be mapped.

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

NFSv4: Remove nfs_client->cl_sem

Now that we're using the flags to indicate state that needs to be
recovered, as well as having implemented proper refcounting and spinlocking
on the state and open_owners, we can get rid of nfs_client->cl_sem. The
only remaining case that was dubious was the file locking, and that case is
now covered by the nfsi->rwsem.

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

NLM: allow lockd requests from an unprivileged port

If the admin has specified the "noresvport" option for an NFS mount
point, the kernel's NFS client uses an unprivileged source port for
the main NFS transport. The kernel's lockd client should use an
unprivileged port in this case as well.

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

NFS: add "[no]resvport" mount option

The standard default security setting for NFS is AUTH_SYS. An NFS
client connects to NFS servers via a privileged source port and a
fixed standard destination port (2049). The client sends raw uid and
gid numbers to identify users making NFS requests, and the server
assumes an appropriate authority on the client has vetted these
values because the source port is privileged.

On Linux, by default in-kernel RPC services use a privileged port in
the range between 650 and 1023 to avoid using source ports of well-
known IP services. Using such a small range limits the number of NFS
mount points and the number of unique NFS servers to which a client
can connect concurrently.

An NFS client can use unprivileged source ports to expand the range of
source port numbers, allowing more concurrent server connections and
more NFS mount points. Servers must explicitly allow NFS connections
from unprivileged ports for this to work.

In the past, bumping the value of the sunrpc.max_resvport sysctl on
the client would permit the NFS client to use unprivileged ports.
Bumping this setting also changes the maximum port number used by
other in-kernel RPC services, some of which still required a port
number less than 1023.

This is exacerbated by the way source port numbers are chosen by the
Linux RPC client, which starts at the top of the range and works
downwards. It means that bumping the maximum means all RPC services
requesting a source port will likely get an unprivileged port instead
of a privileged one.

Changing this setting effects all NFS mount points on a client. A
sysadmin could not selectively choose which mount points would use
non-privileged ports and which could not.

Lastly, this mechanism of expanding the limit on the number of NFS
mount points was entirely undocumented.

To address the need for the NFS client to use a large range of source
ports without interfering with the activity of other in-kernel RPC
services, we introduce a new NFS mount option. This option explicitly
tells only the NFS client to use a non-privileged source port when
communicating with the NFS server for one specific mount point.

This new mount option is called "resvport," like the similar NFS mount
option on FreeBSD and Mac OS X. A sister patch for nfs-utils will be
submitted that documents this new option in nfs(5).

The default setting for this new mount option requires the NFS client
to use a privileged port, as before. Explicitly specifying the
"noresvport" mount option allows the NFS client to use an unprivileged
source port for this mount point when connecting to the NFS server
port.

This mount option is supported only for text-based NFS mounts.

[ Sidebar: it is widely known that security mechanisms based on the
use of privileged source ports are ineffective. However, the NFS
client can combine the use of unprivileged ports with the use of
secure authentication mechanisms, such as Kerberos. This allows a
large number of connections and mount points while ensuring a useful
level of security.

Eventually we may change the default setting for this option
depending on the security flavor used for the mount. For example,
if the mount is using only AUTH_SYS, then the default setting will
be "resvport;" if the mount is using a strong security flavor such
as krb5, the default setting will be "noresvport." ]

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[Trond.Myklebust@netapp.com: Fixed a bug whereby nfs4_init_client()
was being called with incorrect arguments.]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: move nfs_server flag initialization

Make it possible for the NFSv4 mount set up logic to pass mount option
flags down the stack to nfs_create_rpc_client().

This is immediately useful if we want NFS mount options to modulate
settings of the underlying RPC transport, but it may be useful at some
later point if other parts of the NFSv4 mount initialization logic
want to know what the mount options are.

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

NFS: expand flags passed to nfs_create_rpc_client()

The nfs_create_rpc_client() function sets up an RPC client for an NFS
mount point. Add an option that allows it to set up an RPC transport
from an unprivileged port.

Instead of having nfs_create_rpc_client()'s callers retain local
knowledge about how to set up an RPC client, create a couple of flag
arguments to control the use of RPC_CLNT_CREATE flags.

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

NFS: Don't apply NFS_MOUNT_FLAGMASK to text-based mounts

The point of introducing text-based mounts was to allow us to add
functionality without having to worry about legacy binary mount formats.
The mask should be there in order to ensure that binary formats don't start
enabling features that they cannot support. There is no justification for
applying it to the text mount path.

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

NFS: Clean up nfs_sb_active/nfs_sb_deactive

Instead of causing umount requests to block on server->active_wq while the
asynchronous sillyrename deletes are executing, we can use the sb->s_active
counter to obtain a reference to the super_block, and then release that
reference in nfs_async_unlink_release().

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

NFS: set transport defaults after mount option parsing is finished

Move the UDP/TCP default timeo/retrans settings for text mounts to
nfs_init_timeout_values(), which was were they were always being
initialised (and sanity checked) for binary mounts.
Document the default timeout values using appropriate #defines.

Ensure that we initialise and sanity check the transport protocols that
may have been specified by the user.

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

nfs: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs: use proc_create to setup de->proc_fops

Use proc_create() to make sure that ->proc_fops be setup before gluing PDE to
main tree.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

proc: remove proc_root_fs

Use creation by full path instead: "fs/foo".

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NFSv4: Reintroduce machine creds

We need to try to ensure that we always use the same credentials whenever
we re-establish the clientid on the server. If not, the server won't
recognise that we're the same client, and so may not allow us to recover
state.

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

NFS: Save the values of the "mount*=" mount options

Save the value of the mountproto= mountport= mountvers= and mountaddr=
options so that these values can be displayed later via
nfs_show_options().

This preserves the intent of the original mount options, should the file
system need to be remounted based on what's displayed in /proc/mounts.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Save the value of the "port=" mount option

During a remount based on the mount options displayed in /proc/mounts, we
want to preserve the original behavior of the mount request. Let's save
the original setting of the "port=" mount option in the mount's nfs_server
structure.

This allows us to simplify the default behavior of port setting for NFSv4
mounts: by default, NFSv2/3 mounts first try an RPC bind to determine the
NFS server's port, unless the user specified the "port=" mount option;
Users can force the client to skip the RPC bind by explicitly specifying
"port=<value>".

NFSv4, by contrast, assumes the NFS server port is 2049 and skips the RPC
bind, unless the user specifies "port=". Users can force an RPC bind for
NFSv4 by explicitly specifying "port=0".

I added a couple of extra comments to clarify this behavior.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

SUNRPC: Add a (empty for the moment) destructor for rpc_wait_queues

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

NFSv4: Iterate through all nfs_clients when the server recalls a delegation

The same delegation may have been handed out to more than one nfs_client.
Ensure that if a recall occurs, we return all instances.

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

NLM: Introduce an arguments structure for nlmclnt_init()

Clean up: pass 5 arguments to nlmclnt_init() in a structure similar to the
new nfs_client_initdata structure.

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

NFS: Invoke nlmclnt_init during NFS mount processing

Cache an appropriate nlm_host structure in the NFS client's mount point
metadata for later use.

Note that there is no need to set NFS_MOUNT_NONLM in the error case -- if
nfs_start_lockd() returns a non-zero value, its callers ensure that the
mount request fails outright.

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

NFS: Fix the 'proto=' mount option

Currently, if you have a server mounted using networking protocol, you
cannot specify a different value using the 'proto=' option on another
mountpoint.

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

NFS: Support per-mountpoint timeout parameters.

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

NFS: Ensure that we respect NFS_MAX_TCP_TIMEOUT

It isn't sufficient just to limit timeout->to_initval, we also need to
limit to_maxval.

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

NFS: Support non-IPv4 addresses in nfs_parsed_mount_data

Replace the nfs_server and mount_server address fields in the
nfs_parsed_mount_data structure with a "struct sockaddr_storage"
instead of a "struct sockaddr_in".

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>

NFS: Adjust nfs_clone_mount structure to store "struct sockaddr *"

Change the addr field in the nfs_clone_mount structure to store a "struct
sockaddr *" to support non-IPv4 addresses in the NFS client.

Note this is mostly a cosmetic change, and does not actually allow
referrals using IPv6 addresses. The existing referral code assumes that
the server returns a string that represents an IPv4 address. This code
needs to support hostnames and IPv6 addresses as well as IPv4 addresses,
thus it will need to be reorganized completely (to handle DNS resolution
in user space).

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>

NFS: Change nfs4_set_client() to accept struct sockaddr *

Adjust the arguments and callers of nfs4_set_client() to pass a "struct
sockaddr *" instead of a "struct sockaddr_in *" to support non-IPv4
addresses in the NFS client.

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>

NFS: Change nfs_get_client() to take sockaddr *

Adjust arguments and callers of nfs_get_client() to pass a
"struct sockaddr *" instead of "struct sockaddr_in *" to support
non-IPv4 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>

NFS: Change nfs_find_client() to take "struct sockaddr *"

Adjust arguments and callers of nfs_find_client() to pass a
"struct sockaddr *" instead of "struct sockaddr_in *" to support non-IPv4
addresses.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>

Trond: Also fix up protocol version number argument in nfs_find_client() to
use the correct u32 type.

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

NFS: Expand server address storage in nfs_client struct

Prepare for managing larger addresses in the NFS client by widening the
nfs_client struct's cl_addr field.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>

(Modified to work with the new parameters for nfs_alloc_client)
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Add support for AF_INET6 addresses in __nfs_find_client()

Introduce AF_INET6-specific address checking to __nfs_find_client().

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

NFS: eliminate NIPQUAD(clp->cl_addr.sin_addr)

To ensure the NFS client displays IPv6 addresses properly, replace
address family-specific NIPQUAD() invocations with a call to the RPC
client to get a formatted string representing the remote peer's
address.

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>

NFS: Remove the redundant nfs_client->cl_nfsversion

We can get the same information from the rpc_ops structure instead.

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

NFS: Clean up the nfs_find_client function.

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

NFS: Clean up the nfs_client initialisation

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

NFS: Clean up address comparison in __nfs_find_client()

The address comparison in the __nfs_find_client() function is deceptive.
It uses a memcmp() to check a pair of u32 fields for equality. Not only is
this inefficient, but usually memcmp() is used for comparing two *whole*
sockaddr_in's (which includes comparisons of the address family and port
number), so it's easy to mistake the comparison here for a whole sockaddr
comparison, which it isn't.

So for clarity and efficiency, we replace the memcmp() with a simple test
for equality between the two s_addr fields. This should have no
behavioral effect.

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

NFS: Stop sillyname renames and unmounts from racing

Added an active/deactive mechanism to the nfs_server structure
allowing async operations to hold off umount until the
operations are done.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv2/v3: Fix a memory leak when using -onolock

Neil Brown said:
> Hi Trond,
>
> We found that a machine which made moderately heavy use of
> 'automount' was leaking some nfs data structures - particularly the
> 4K allocated by rpc_alloc_iostats.
> It turns out that this only happens with filesystems with -onolock
> set.

> The problem is that if NFS_MOUNT_NONLM is set, nfs_start_lockd doesn't
> set server->destroy, so when the filesystem is unmounted, the
> ->client_acl is not shutdown, and so several resources are still
> held. Multiple mount/umount cycles will slowly eat away memory
> several pages at a time.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NeilBrown <neilb@suse.de>

NFS: Switch from intr mount option to TASK_KILLABLE

By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr'
mount option. We have to use _killable everywhere instead of _interruptible
as we get rid of rpc_clnt_sigmask/sigunmask.

Signed-off-by: Liam R. Howlett <howlett@gmail.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>

mm: bdi init hooks

provide BDI constructor/destructor hooks

[akpm@linux-foundation.org: compile fix]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NFS: support RDMA mounts

Adds hooks to the string-based NFS mount to support an "rdma" protocol option.

Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS/SUNRPC: use transport protocol naming

Instead of an { address family, raw IP protocol number }-tuple, use the
newly-defined RPC identifier when creating clients in the upper layers.

Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: use in-kernel mount argument structure for nfsv4 mounts

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>

NFS: use in-kernel mount argument structure for nfsv[23] mounts

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>

NFS: Fix an Oops in encode_lookup()

It doesn't look as if the NFS file name limit is being initialised correctly
in the struct nfs_server. Make sure that we limit whatever is being set in
nfs_probe_fsinfo() and nfs_init_server().

Also ensure that readdirplus and nfs4_path_walk respect our file name
limits.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Make NFS client use seq_list_xxx helpers

This includes /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes entries.

Both need to show the header and use the list_head.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NFSv4: Reduce the chances of an open_owner identifier collision

Currently we just use a 32-bit counter.

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

NFSv4: Don't reuse expired nfs4_state_owner structs

That just confuses certain NFSv4 servers.

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

SUNRPC: Remove redundant calls to rpciod_up()/rpciod_down()

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

Detach sched.h from mm.h

First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.

This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly

Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).

Cross-compile tested on

all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig

as well as my two usual configs.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

header cleaning: don't include smp_lock.h when not used

Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NFS: Added support to turn off the NFSv3 READDIRPLUS RPC.

READDIRPLUS can be a performance hindrance when the client is working with
large directories. In addition, some servers still have bugs in their
implementations (e.g. Tru64 returns wrong values for the fsid).

Add a mount flag to enable users to turn it off at mount time following the
implementation in Apple's NFS client.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: disconnect before retrying NFSv4 requests over TCP

RFC3530 section 3.1.1 states an NFSv4 client MUST NOT send a request
twice on the same connection unless it is the NULL procedure. Section
3.1.1 suggests that the client should disconnect and reconnect if it
wants to retry a request.

Implement this by adding an rpc_clnt flag that an ULP can use to
specify that the underlying transport should be disconnected on a
major timeout. The NFSv4 client asserts this new flag, and requests
no retries after a minor retransmit timeout.

Note that disconnecting on a retransmit is in general not safe to do
if the RPC client does not reuse the TCP port number when reconnecting.

See http://bugzilla.linux-nfs.org/show_bug.cgi?id=6

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

[PATCH] mark struct file_operations const 6

Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NFSv4: Fix Oops in nfs4_create_referral_server

The filehandle that is passed into nfs4_create_referral_server is
not initialised. The expectation is that nfs4_create_referral_server will
initialise it, and return it to the caller.

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

WorkStruct: Pass the work_struct pointer instead of context data

Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.

For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.

To make this work, an extra flag is introduced into the management side of the
work_struct. This governs auto-release of the structure upon execution.

Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function. This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated.. This is a
problem if the auxiliary data is taken away (as done by the last patch).

However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems. But then the work function must itself release the
work_struct by calling work_release().

In most cases, automatic release is fine, so this is the default. Special
initiators exist for the non-auto-release case (ending in _NAR).


Signed-Off-By: David Howells <dhowells@redhat.com>

WorkStruct: Separate delayable and non-delayable events.

Separate delayable work items from non-delayable work items be splitting them
into a separate structure (delayed_work), which incorporates a work_struct and
the timer_list removed from work_struct.

The work_struct struct is huge, and this limits it's usefulness. On a 64-bit
architecture it's nearly 100 bytes in size. This reduces that by half for the
non-delayable type of event.

Signed-Off-By: David Howells <dhowells@redhat.com>

[PATCH] NFS: Fix NFSv4 callback regression

The change in semantics for nfs_find_client() introduced by David breaks the
NFSv4 callback channel.

Also, replace another completely broken BUG_ON() in nfs_find_client(). In
initialised clients, clp->cl_cons_state == 0, and callers of that function
should in any case never want to see clients that are uninitialised.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] nfs4: initialize cl_ipaddr

David forgot to do this. I'm not sure if this is the right place to put
it....

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>