Convert nfs_map_name_to_uid to return a kuid_t value.
Convert nfs_map_name_to_gid to return a kgid_t value.
Convert nfs_map_uid_to_name to take a kuid_t paramater.
Convert nfs_map_gid_to_name to take a kgid_t paramater.

Tweak nfs_fattr_map_owner_to_name to use a kuid_t intermediate value.
Tweak nfs_fattr_map_group_to_name to use a kgid_t intermediate value.

Which makes these functions properly handle kuids and kgids, including
erroring of the generated kuid or kgid is invalid.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NMichael Kerrisk <mtk.manpages@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NDave Jones <davej@redhat.com>

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

When compiled without NFS v4 configured these function won't be defined
and the compiler will yell.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch removes the old hashmap-based caching and instead uses a
"request key actor" to place an upcall to the legacy idmapper rather
than going through /sbin/request-key.  This will only be used as a
fallback if /etc/request-key.conf isn't configured to use nfsidmap.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch removes the CONFIG_NFS_USE_NEW_IDMAPPER compile option.
First, the idmapper will attempt to map the id using /sbin/request-key
and nfsidmap.  If this fails (if /etc/request-key.conf is not configured
properly) then the idmapper will call the legacy code to perform the
mapping.  I left a comment stating where the legacy code begins to make
it easier for somebody to remove in the future.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

...so that we can do the uid/gid mapping outside the asynchronous RPC
context.
This fixes a bug in the current NFSv4 atomic open code where the client
isn't able to determine what the true uid/gid fields of the file are,
(because the asynchronous nature of the OPEN call denies it the ability
to do an upcall) and so fills them with default values, marking the
inode as needing revalidation.
Unfortunately, in some cases, the VFS will do some additional sanity
checks on the file, and may override the server's decision to allow
the open because it sees the wrong owner/group fields.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

...instead of the nfs_client.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch creates a new idmapper system that uses the request-key function to
place a call into userspace to map user and group ids to names.  The old
idmapper was single threaded, which prevented more than one request from running
at a single time.  This means that a user would have to wait for an upcall to
finish before accessing a cached result.

The upcall result is stored on a keyring of type id_resolver.  See the file
Documentation/filesystems/nfs/idmapper.txt for instructions.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
[Trond: fix up the return value of nfs_idmap_lookup_name and clean up code]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

fix the following 'make headers_check' warning:

  usr/include/linux/nfs_idmap.h:55: found __[us]{8,16,32,64} type without #include <linux/types.h>
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>

Return an error when starting the idmapping pipe so that we can detect it
failing.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

 If someone changes the uid/gid mapping in userland, then we do eventually
 want those changes to be propagated to the kernel. Currently the kernel
 assumes that it may cache entries forever.

 Add an expiration time + garbage collector for idmap entries.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!