Dynamic slot allocation in NFSv4.1 depends on the client being able to
track the server's target value for the highest slotid in the
slot table.  See the reference in Section 2.10.6.1 of RFC5661.

To avoid ordering problems in the case where 2 SEQUENCE replies contain
conflicting updates to this target value, we also introduce a generation
counter, to track whether or not an RPC containing a SEQUENCE operation
was launched before or after the last update.

Also rename the nfs4_slot_table target_max_slots field to
'target_highest_slotid' to avoid confusion with a slot
table size or number of slots.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Replace the session pointer + slotid with a pointer to the
allocated slot.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Instead of doing slot table pointer gymnastics every time we want to
know which slot we're using.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move the session pointer into the slot table, then have struct nfs4_slot
point to that slot table.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Convert the ones that are not trivial to check into WARN_ON_ONCE().
Remove checks for things such as NFS2_MAXPATHLEN, which are trivially
done by the caller.

Add a comment to the case of nfs3_xdr_enc_setacl3args. What is being
done there is just wrong...
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We currently make no distinction in attribute requests between normal OPENs
and OPEN with CLAIM_PREVIOUS.  This offers more possibility of failures in
the GETATTR response which foils OPEN reclaim attempts.

Reduce the requested attributes to the bare minimum needed to update the
reclaim open stateid and split nfs4_opendata_to_nfs4_state processing
accordingly.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Don't put an ACCESS op in OPEN compound if O_EXCL, because ACCESS
will return permission denied for all bits until close.

Fixes a regression due to commit 6168f62c (NFSv4: Add ACCESS operation to
OPEN compound)
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The OPEN operation has no way to differentiate an open for read and an
open for execution - both look like read to the server. This allowed
users to read files that didn't have READ access but did have EXEC access,
which is obviously wrong.

This patch adds an ACCESS call to the OPEN compound to handle the
difference between OPENs for reading and execution.  Since we're going
through the trouble of calling ACCESS, we check all possible access bits
and cache the results hopefully avoiding an ACCESS call in the future.
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We want to be able to pass on the information that the page was not
dirtied under a lock. Instead of adding a flag parameter, do this
by passing a pointer to a 'struct nfs_lock_owner' that may be NULL.

Also reuse this structure in struct nfs_lock_context to carry the
fl_owner_t and pid_t.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

If decode_getfh failed, nfs4_xdr_dec_open would return 0 since the last
decode_* call must have succeeded.

Cc: stable@vger.kernel.org
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Pass the checks made by decode_getacl back to __nfs4_get_acl_uncached
so that it knows if the acl has been truncated.

The current overflow checking is broken, resulting in Oopses on
user-triggered nfs4_getfacl calls, and is opaque to the point
where several attempts at fixing it have failed.
This patch tries to clean up the code in addition to fixing the
Oopses by ensuring that the overflow checks are performed in
a single place (decode_getacl). If the overflow check failed,
we will still be able to report the acl length, but at least
we will no longer attempt to cache the acl or copy the
truncated contents to user space.
Reported-by: NSachin Prabhu <sprabhu@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: NSachin Prabhu <sprabhu@redhat.com>

Instead of using the private field xdr->p from struct xdr_stream,
use the public xdr_stream_pos().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Resetting the cursor xdr->p to a previous value is not a safe
practice: if the xdr_stream has crossed out of the initial iovec,
then a bunch of other fields would need to be reset too.

Fix this issue by using xdr_enter_page() so that the buffer gets
page aligned at the bitmap _before_ we decode it.

Also fix the confusion of the ACL length with the page buffer length
by not adding the base offset to the ACL length...
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org

Otherwise we break backwards compatibility when v4 becomes a modules.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

fl_type is not a bitmap.
Reported-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The 'committed' field is not needed once we have put the struct nfs_page
on the right list.

Also correct the type of the verifier: it is not an array of __be32, but
simply an 8 byte long opaque array.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The verifier returned by the GETDEVICELIST operation is not a write
verifier, but a nfs4_verifier.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Use the xdr_stream position counter as the basis for the calculation
instead of assuming that we can calculate an offset to the start
of the iovec.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

xdr_read_pages will already do all of the buffer overflow checks that are
currently being open-coded in the various callers. This patch simplifies
the existing code by replacing the open coded checks.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Fix an incorrect use of 'likely()'. The FATTR4_WORD2_MDSTHRESHOLD
bit is only expected in NFSv4.1 OPEN calls, and so is actually
rather _unlikely_.

decode_attr_mdsthreshold needs to clear FATTR4_WORD2_MDSTHRESHOLD
from the attribute bitmap after it has decoded the data.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Andy Adamson <andros@netapp.com>

The open recovery code does not need to request a new value for the
mdsthreshold, and so does not allocate a struct nfs4_threshold.
The problem is that encode_getfattr_open() will still request an
mdsthreshold, and so we end up Oopsing in decode_attr_mdsthreshold.

This patch fixes encode_getfattr_open so that it doesn't request an
mdsthreshold when the caller isn't asking for one. It also fixes
decode_attr_mdsthreshold so that it errors if the server returns
an mdsthreshold that we didn't ask for (instead of Oopsing).
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Andy Adamson <andros@netapp.com>

If the EXCHGID4_FLAG_CONFIRMED_R flag is set, the client is in theory
supposed to already know the correct value of the seqid, in which case
RFC5661 states that it should ignore the value returned.

Also ensure that if the sanity check in nfs4_check_cl_exchange_flags
fails, then we must not change the nfs_client fields.

Finally, clean up the code: we don't need to retest the value of
'status' unless it can change.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ensure that we destroy our lease on last unmount
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For backward compatibility with nfs-utils.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Weston Andros Adamson <dros@netapp.com>

This patch adds the BIND_CONN_TO_SESSION operation which is needed for
upcoming SP4_MACH_CRED work and useful for recovering from broken connections
without destroying the session.
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We only support one layout type per file system, so one threshold_item4 per
mdsthreshold4.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Save the server major and minor ID results from EXCHANGE_ID, as they
are needed for detecting server trunking.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

No attributes are supposed to change during a COMMIT call, so there
is no need to request post-op attributes.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Get rid of the post-op GETATTR on the directory in order to reduce
the amount of processing done on the server.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Get rid of the post-op GETATTR on the directory in order to reduce
the amount of processing done on the server.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Get rid of the post-op GETATTR on the directory in order to reduce
the amount of processing done on the server.

The cost is that if we later need to stat() the directory, then we
know that the ctime and mtime are likely to be invalid.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In order to retrieve cache consistency attributes before
anyone else has a chance to change the inode, we need to
put the GETATTR op _before_ the DELEGRETURN op.

We can then use that as part of a 'nfs_post_op_update_inode_force_wcc()'
call, to ensure that we update the attributes without clearing our
cached data.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Commits don't need the vectors of pages, etc. that writes do. Split out
a separate structure for the commit operation.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Whenever lookup sees wrongsec do a secinfo and retry the lookup to find
attributes of the file or directory, such as "is this a referral
mountpoint?".  This also allows me to remove handling -NFS4ERR_WRONSEC
as part of getattr xdr decoding.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

I was using the same decoder function for SECINFO and SECINFO_NO_NAME,
so it was returning an error when it tried to decode an OP_SECINFO_NO_NAME
header as OP_SECINFO.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When attempting to cache ACLs returned from the server, if the bitmap
size + the ACL size is greater than a PAGE_SIZE but the ACL size itself
is smaller than a PAGE_SIZE, we can read past the buffer page boundary.
Signed-off-by: NSachin Prabhu <sprabhu@redhat.com>
Reported-by: NJian Li <jiali@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Bug noticed in commit
bf118a34

When calling GETACL, if the size of the bitmap array, the length
attribute and the acl returned by the server is greater than the
allocated buffer(args.acl_len), we can Oops with a General Protection
fault at _copy_from_pages() when we attempt to read past the pages
allocated.

This patch allocates an extra PAGE for the bitmap and checks to see that
the bitmap + attribute_length + ACLs don't exceed the buffer space
allocated to it.
Signed-off-by: NSachin Prabhu <sprabhu@redhat.com>
Reported-by: NJian Li <jiali@redhat.com>
[Trond: Fixed a size_t vs unsigned int printk() warning]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>