nfs42: client needs to strip file mode's suid/sgid bit after ALLOCATE op

The Linux NFS server strips the SUID and SGID from the file mode
on ALLOCATE op.

Modify _nfs42_proc_fallocate to add NFS_INO_REVAL_FORCED to
nfs_set_cache_invalid's argument to force update of the file
mode suid/sgid bit.

Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4.2: fix handling of COPY ERR_OFFLOAD_NO_REQ

If the client sent a synchronous copy and the server replied with
ERR_OFFLOAD_NO_REQ indicating that it wants an asynchronous
copy instead, the client should retry with asynchronous copy.

Fixes: 539f57b3e0fd ("NFS handle COPY ERR_OFFLOAD_NO_REQS")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4.2: fix error handling in nfs42_proc_getxattr

There is a slight issue with error handling code inside
nfs42_proc_getxattr(). If page allocating loop fails then we free the
failing page array element which is NULL but __free_page() can't deal with
NULL args.

Found by Linux Verification Center (linuxtesting.org).

Fixes: a1f26739ccdc ("NFSv4.2: improve page handling for GETXATTR")
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2: SETXATTR should update ctime

Otherwise, `stat` will report a stale value to users.

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

nfs42: do not fail with EIO if ssc returns NFS4ERR_OFFLOAD_DENIED

The NFSv4.2 server even if supports intra-SSC might prefer that for
a particular file a classic copy is performed. As returning ENOTSUPP
will clear the SSC capability of the server by the client, server
might return NFS4ERR_OFFLOAD_DENIED (well, spec talks about remote
servers there).

Update nfs42_proc_copy to handle NFS4ERR_OFFLOAD_DENIED as ENOTSUPP,
but without clearing NFS_CAP_COPY bit.

Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4.2: Fixup CLONE dest file size for zero-length count

When holding a delegation, the NFS client optimizes away setting the
attributes of a file from the GETATTR in the compound after CLONE, and for
a zero-length CLONE we will end up setting the inode's size to zero in
nfs42_copy_dest_done(). Handle this case by computing the resulting count
from the server's reported size after CLONE's GETATTR.

Suggested-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: 94d202d5ca39 ("NFSv42: Copy offload should update the file size when appropriate")
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4.2: Add a tracepoint for listxattr

This can be defined as simply an NFS4_INODE_EVENT() since we don't have
the name of a specific xattr to list. This roughly matches readdir,
which also uses an NFS4_INODE_EVENT() tracepoint.

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

NFSv4.2: Add tracepoints for getxattr, setxattr, and removexattr

These functions take similar arguments, and can share a tracepoint class
for common formatting.

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

_nfs42_proc_copy(): use ->f_mapping instead of file_inode()->i_mapping

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

NFSv4.2: Update mode bits after ALLOCATE and DEALLOCATE

The fallocate call invalidates suid and sgid bits as part of normal
operation. We need to mark the mode bits as invalid when using fallocate
with an suid so these will be updated the next time the user looks at them.

This fixes xfstests generic/683 and generic/684.

Reported-by: Yue Cui <cuiyue-fnst@fujitsu.com>
Fixes: 913eca1aea87 ("NFS: Fallocate should use the nfs4_fattr_bitmap")
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4/pnfs: Ensure pNFS allocation modes are consistent with nfsiod

Ensure that pNFS allocations that can be called from rpciod/nfsiod
callback can fail in low memory mode, so that the threads don't block
and loop forever.

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

NFSv4.2/copyoffload: Convert GFP_NOFS to GFP_KERNEL

There doesn't seem to be any reason why the copy offload code can't use
GFP_KERNEL. It can't get called by direct reclaim.

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

NFSv4/flexfiles: Convert GFP_NOFS to GFP_KERNEL

Assume that the higher layers will have set memalloc_nofs_save/restore
as appropriate.

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

NFSv4.2: fix reference count leaks in _nfs42_proc_copy_notify()

[You don't often get email from xiongx18@fudan.edu.cn. Learn why this is important at http://aka.ms/LearnAboutSenderIdentification.]

The reference counting issue happens in two error paths in the
function _nfs42_proc_copy_notify(). In both error paths, the function
simply returns the error code and forgets to balance the refcount of
object `ctx`, bumped by get_nfs_open_context() earlier, which may
cause refcount leaks.

Fix it by balancing refcount of the `ctx` object before the function
returns in both error paths.

Signed-off-by: Xin Xiong <xiongx18@fudan.edu.cn>
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv42: Fallocate and clone should also request 'blocks used'

Both fallocate and clone can end up updating the blocks used attribute.

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

NFSv42: Fix pagecache invalidation after COPY/CLONE

The mechanism in use to allow the client to see the results of COPY/CLONE
is to drop those pages from the pagecache. This forces the client to read
those pages once more from the server. However, truncate_pagecache_range()
zeros out partial pages instead of dropping them. Let us instead use
invalidate_inode_pages2_range() with full-page offsets to ensure the client
properly sees the results of COPY/CLONE operations.

Cc: <stable@vger.kernel.org> # v4.7+
Fixes: 2e72448b07dc ("NFS: Add COPY nfs operation")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2 add tracepoint to OFFLOAD_CANCEL

Add tracepoint to OFFLOAD_CANCEL operation.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2 add tracepoint to COPY_NOTIFY

Add a tracepoint to COPY_NOTIFY operation.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2 add tracepoint to CLONE

Add a tracepoint to the CLONE operation.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2 add tracepoint to COPY

Add a tracepoint to the COPY operation.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2 add tracepoints to FALLOCATE and DEALLOCATE

Add a tracepoint to the FALLOCATE/DEALLOCATE operations.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2 add tracepoint to SEEK

Add a tracepoint to the SEEK operation.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv42: Don't force attribute revalidation of the copy offload source

When a copy offload is performed, we do not expect the source file to
change other than perhaps to see the atime be updated.

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

NFSv42: Copy offload should update the file size when appropriate

If the result of a copy offload or clone operation is to grow the
destination file size, then we should update it. The reason is that when
a client holds a delegation, it is authoritative for the file size.

Fixes: 16abd2a0c124 ("NFSv4.2: fix client's attribute cache management for copy_file_range")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2 fix handling of sr_eof in SEEK's reply

Currently the client ignores the value of the sr_eof of the SEEK
operation. According to the spec, if the server didn't find the
requested extent and reached the end of the file, the server
would return sr_eof=true. In case the request for DATA and no
data was found (ie in the middle of the hole), then the lseek
expects that ENXIO would be returned.

Fixes: 1c6dcbe5ceff8 ("NFS: Implement SEEK")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2: Always flush out writes in nfs42_proc_fallocate()

Whether we're allocating or delallocating space, we should flush out the
pending writes in order to avoid races with attribute updates.

Fixes: 1e564d3dbd68 ("NFSv4.2: Fix a race in nfs42_proc_deallocate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Fix attribute bitmask in _nfs42_proc_fallocate()

We can't use nfs4_fattr_bitmap as a bitmask, because it hasn't been
filtered to represent the attributes supported by the server. Instead,
let's revert to using server->cache_consistency_bitmask after adding in
the missing SPACE_USED attribute.

Fixes: 913eca1aea87 ("NFS: Fallocate should use the nfs4_fattr_bitmap")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Fix open coded versions of nfs_set_cache_invalid() in NFSv4

nfs_set_cache_invalid() has code to handle delegations, and other
optimisations, so let's use it when appropriate.

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

NFSv4.2: fix error return on memory allocation failure

Currently when an alloc_page fails the error return is not set in
variable err and a garbage initialized value is returned. Fix this
by setting err to -ENOMEM before taking the error return path.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: a1f26739ccdc ("NFSv4.2: improve page handling for GETXATTR")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2: improve page handling for GETXATTR

XDRBUF_SPARSE_PAGES can cause problems for the RDMA transport,
and it's easy enough to allocate enough pages for the request
up front, so do that.

Also, since we've allocated the pages anyway, use the full
page aligned length for the receive buffer. This will allow
caching of valid replies that are too large for the caller,
but that still fit in the allocated pages.

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

NFS: Fix rpcrdma_inline_fixup() crash with new LISTXATTRS operation

By switching to an XFS-backed export, I am able to reproduce the
ibcomp worker crash on my client with xfstests generic/013.

For the failing LISTXATTRS operation, xdr_inline_pages() is called
with page_len=12 and buflen=128.

- When ->send_request() is called, rpcrdma_marshal_req() does not
set up a Reply chunk because buflen is smaller than the inline
threshold. Thus rpcrdma_convert_iovs() does not get invoked at
all and the transport's XDRBUF_SPARSE_PAGES logic is not invoked
on the receive buffer.

- During reply processing, rpcrdma_inline_fixup() tries to copy
received data into rq_rcv_buf->pages because page_len is positive.
But there are no receive pages because rpcrdma_marshal_req() never
allocated them.

The result is that the ibcomp worker faults and dies. Sometimes that
causes a visible crash, and sometimes it results in a transport hang
without other symptoms.

RPC/RDMA's XDRBUF_SPARSE_PAGES support is not entirely correct, and
should eventually be fixed or replaced. However, my preference is
that upper-layer operations should explicitly allocate their receive
buffers (using GFP_KERNEL) when possible, rather than relying on
XDRBUF_SPARSE_PAGES.

Reported-by: Olga kornievskaia <kolga@netapp.com>
Suggested-by: Olga kornievskaia <kolga@netapp.com>
Fixes: c10a75145feb ("NFSv4.2: add the extended attribute proc functions.")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Olga kornievskaia <kolga@netapp.com>
Reviewed-by: Frank van der Linden <fllinden@amazon.com>
Tested-by: Olga kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Fix rpcrdma_inline_fixup() crash with new LISTXATTRS operation

By switching to an XFS-backed export, I am able to reproduce the
ibcomp worker crash on my client with xfstests generic/013.

For the failing LISTXATTRS operation, xdr_inline_pages() is called
with page_len=12 and buflen=128.

- When ->send_request() is called, rpcrdma_marshal_req() does not
set up a Reply chunk because buflen is smaller than the inline
threshold. Thus rpcrdma_convert_iovs() does not get invoked at
all and the transport's XDRBUF_SPARSE_PAGES logic is not invoked
on the receive buffer.

- During reply processing, rpcrdma_inline_fixup() tries to copy
received data into rq_rcv_buf->pages because page_len is positive.
But there are no receive pages because rpcrdma_marshal_req() never
allocated them.

The result is that the ibcomp worker faults and dies. Sometimes that
causes a visible crash, and sometimes it results in a transport hang
without other symptoms.

RPC/RDMA's XDRBUF_SPARSE_PAGES support is not entirely correct, and
should eventually be fixed or replaced. However, my preference is
that upper-layer operations should explicitly allocate their receive
buffers (using GFP_KERNEL) when possible, rather than relying on
XDRBUF_SPARSE_PAGES.

Reported-by: Olga kornievskaia <kolga@netapp.com>
Suggested-by: Olga kornievskaia <kolga@netapp.com>
Fixes: c10a75145feb ("NFSv4.2: add the extended attribute proc functions.")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Olga kornievskaia <kolga@netapp.com>
Reviewed-by: Frank van der Linden <fllinden@amazon.com>
Tested-by: Olga kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4.2: fix client's attribute cache management for copy_file_range

After client is done with the COPY operation, it needs to invalidate
its pagecache (as it did no reading or writing of the data locally)
and it needs to invalidate it's attributes just like it would have
for a read on the source file and write on the destination file.

Once the linux server started giving out read delegations to
read+write opens, the destination file of the copy_file range
started having delegations and not doing syncup on close of the
file leading to xfstest failures for generic/430,431,432,433,565.

v2: changing cache_validity needs to be protected by the i_lock.

Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Fixes: 2e72448b07dc ("NFS: Add COPY nfs operation")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Add tracepoints for layouterror and layoutstats.

Allow tracing of the NFSv4.2 layouterror and layoutstats operations.

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

NFSv4.2: add client side xattr caching.

Implement client side caching for NFSv4.2 extended attributes. The cache
is a per-inode hashtable, with name/value entries. There is one special
entry for the listxattr cache.

NFS inodes have a pointer to a cache structure. The cache structure is
allocated on demand, freed when the cache is invalidated.

Memory shrinkers keep the size in check. Large entries (> PAGE_SIZE)
are collected by a separate shrinker, and freed more aggressively
than others.

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

NFSv4.2: add the extended attribute proc functions.

Implement the extended attribute procedures for NFSv4.2 extended
attribute support (RFC 8276).

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

NFS: Fix memory leaks

In _nfs42_proc_copy(), 'res->commit_res.verf' is allocated through
kzalloc() if 'args->sync' is true. In the following code, if
'res->synchronous' is false, handle_async_copy() will be invoked. If an
error occurs during the invocation, the following code will not be executed
and the error will be returned . However, the allocated
'res->commit_res.verf' is not deallocated, leading to a memory leak. This
is also true if the invocation of process_copy_commit() returns an error.

To fix the above leaks, redirect the execution to the 'out' label if an
error is encountered.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4.x recover from pre-mature loss of openstateid

Ever since the commit 0e0cb35b417f, it's possible to lose an open stateid
while retrying a CLOSE due to ERR_OLD_STATEID. Once that happens,
operations that require openstateid fail with EAGAIN which is propagated
to the application then tests like generic/446 and generic/168 fail with
"Resource temporarily unavailable".

Instead of returning this error, initiate state recovery when possible to
recover the open stateid and then try calling nfs4_select_rw_stateid()
again.

Fixes: 0e0cb35b417f ("NFSv4: Handle NFS4ERR_OLD_STATEID in CLOSE/OPEN_DOWNGRADE")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4: Make _nfs42_proc_copy_notify() static

Fix sparse warning:

fs/nfs/nfs42proc.c:527:5: warning:
symbol '_nfs42_proc_copy_notify' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Fallocate should use the nfs4_fattr_bitmap

Changing a sparse file could have an effect not only on the file size,
but also on the number of blocks used by the file in the underlying
filesystem. The server's cache_consistency_bitmap doesn't update the
SPACE_USED attribute, so let's switch to the nfs4_fattr_bitmap to catch
this update whenever we do an ALLOCATE or DEALLOCATE.

This patch fixes xfstests generic/568, which tests that fallocating an
unaligned range allocates all blocks touched by that range. Without this
patch, `stat` reports 0 bytes used immediately after the fallocate.
Adding a `sleep 5` to the test also catches the update, but it's better
to do so when we know something has changed.

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

NFS based on file size issue sync copy or fallback to generic copy offload

For small file sizes, it make sense to issue a synchronous copy (and
save an RPC callback operation). Also, for the inter copy offload,
copy len must be larger than the cost of doing a mount between the
destination and source server (14RPCs are sent during 4.x mount).

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

NFS: handle source server reboot

When the source server reboots after a server-to-server copy was
issued, we need to retry the copy from COPY_NOTIFY. We need to
detect that the source server rebooted and there is a copy waiting
on a destination server and wake it up.

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

NFS: also send OFFLOAD_CANCEL to source server

In case of copy is cancelled, also send OFFLOAD_CANCEL to the source
server.

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

NFS: COPY handle ERR_OFFLOAD_DENIED

If server sends ERR_OFFLOAD_DENIED error, the client must fall
back on doing copy the normal way. Return ENOTSUPP to the vfs and
fallback to regular copy.

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

NFS: for "inter" copy treat ESTALE as ENOTSUPP

If the client sends an "inter" copy to the destination server but
it only supports "intra" copy, it can return ESTALE (since it
doesn't know anything about the file handle from the other server
and does not recognize the special case of "inter" copy). Translate
this error as ENOTSUPP and also send OFFLOAD_CANCEL to the source
server so that it can clean up state.

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

NFS: add ca_source_server<> to COPY

Support only one source server address: the same address that
the client and source server use.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

NFS: add COPY_NOTIFY operation

Try using the delegation stateid, then the open stateid.

Only NL4_NETATTR, No support for NL4_NAME and NL4_URL.
Allow only one source server address to be returned for now.

To distinguish between same server copy offload ("intra") and
a copy between different server ("inter"), do a check of server
owner identity and also make sure server is capable of doing
a copy offload.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

NFSv4.1 fix incorrect return value in copy_file_range

According to the NFSv4.2 spec if the input and output file is the
same file, operation should fail with EINVAL. However, linux
copy_file_range() system call has no such restrictions. Therefore,
in such case let's return EOPNOTSUPP and allow VFS to fallback
to doing do_splice_direct(). Also when copy_file_range is called
on an NFSv4.0 or 4.1 mount (ie., a server that doesn't support
COPY functionality), we also need to return EOPNOTSUPP and
fallback to a regular copy.

Fixes xfstest generic/075, generic/091, generic/112, generic/263
for all NFSv4.x versions.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.2: Add client support for the generic 'layouterror' RPC call

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

NFSv4.2 copy do not allocate memory under the lock

Bruce pointed out that we shouldn't allocate memory while holding
a lock in the nfs4_callback_offload() and handle_async_copy()
that deal with a racing CB_OFFLOAD and reply to COPY case.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS recover from destination server reboot for copies

Mark the destination state to indicate a server-side copy is
happening. On detecting a reboot and recovering open state check
if any state is engaged in a server-side copy, if so, find the
copy and mark it and then signal the waiting thread. Upon wakeup,
if copy was marked then propage EAGAIN to the nfsd_copy_file_range
and restart the copy from scratch.

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

NFS add a simple sync nfs4_proc_commit after async COPY

A COPY with unstable write data needs a simple sync commit.
Filehandle value is gotten as a part of the inner loop so in
case of a reboot retry it should get the new value.

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

NFS handle COPY ERR_OFFLOAD_NO_REQS

If client sent async COPY and server replied with
ERR_OFFLOAD_NO_REQS, client should retry with a synchronous copy.

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

NFS send OFFLOAD_CANCEL when COPY killed

When COPY is killed by the user send OFFLOAD_CANCEL to server
processing the copy.

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

NFS handle COPY reply CB_OFFLOAD call race

It's possible that server replies back with CB_OFFLOAD call and
COPY reply at the same time such that client will process
CB_OFFLOAD before reply to COPY. For that keep a list of pending
callback stateids received and then before waiting on completion
check the pending list.

Cleanup any pending copies on the client shutdown.

Signed-off-by: Olga Kornievskaia <kolga@netapp.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>

NFSv4: Always clear the pNFS layout when handling ESTALE

If we get an ESTALE error in response to an RPC call operating on the
file on the MDS, we should immediately cancel the layout for that file.

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

NFS: Pass "privileged" value to nfs4_init_sequence()

We currently have a separate function just to set this, but I think it
makes more sense to set it at the same time as the other values in
nfs4_init_sequence()

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

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFSv4.2 fix size storage for nfs42_proc_copy

Return size of COPY is u64 but it was assigned to an "int" status.

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

NFS fix COMMIT after COPY

Fix a typo in the commit e092693443b995c8e3a565a73b5fdb05f1260f9b
"NFS append COMMIT after synchronous COPY"

Reported-by: Eryu Guan <eguan@redhat.com>
Fixes: e092693443b ("NFS append COMMIT after synchronous COPY")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Tested-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS append COMMIT after synchronous COPY

Instead of messing with the commit path which has been causing issues,
add a COMMIT op after the COPY and ask for stable copies in the first
space.

It saves a round trip, since after the COPY, the client sends a COMMIT
anyway.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

pNFS: Ensure we commit the layout if it has been invalidated

If the layout is being invalidated on the server, then we must
invoke nfs_commit_inode() to ensure any commits to the DS get
cleared out.

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

NFS: Clean up nfs42_layoutstat_done()

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

NFSv4: Fix reboot recovery in copy offload

Copy offload code needs to be hooked into the code for handling
NFS4ERR_BAD_STATEID by ensuring that we set the "stateid" field
in struct nfs4_exception.

Reported-by: Olga Kornievskaia <aglo@umich.edu>
Fixes: 2e72448b07dc3 ("NFS: Add COPY nfs operation")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Use nfs4_setup_sequence() everywhere

This does the right thing depending on if we have a session, rather than
needing to handle this manually in multiple places.

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

NFS: Change nfs4_get_session() to take an nfs_client structure

pNFS only has access to the nfs_client structure, and not the
nfs_server, so we need to make this change so the function can be used
by pNFS as well.

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

NFS: Move nfs4_get_session() into nfs4_session.h

This puts session related functions together in the same space. I only
keep one version of this function, since this variable will always be
NULL when using NFS v4.0.

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

pNFS/flexfiles: Minor refactoring before adding iostats to layoutreturn

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

NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic

The caller of rpc_run_task also gets a reference that must be put.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

pNFS: Handle NFS4ERR_OLD_STATEID correctly in LAYOUTSTAT calls

We normally want to update the stateid and then retry,

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

NFSv4.2: LAYOUTSTATS may return NFS4ERR_ADMIN/DELEG_REVOKED

We should handle those errors in the same way we handle the other
stateid errors: by invalidating the faulty layout stateid.

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

pNFS: Cleanup - don't open code pnfs_mark_layout_stateid_invalid()

Ensure nfs42_layoutstat_done() layoutget don't open code layout stateid
invalidation.

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

NFSv4.2: llseek(SEEK_HOLE) and llseek(SEEK_DATA) don't require data sync

We want to ensure that we write the cached data to the server, but
don't require it be synced to disk. If the server reboots, we will
get a stateid error, which will cause us to retry anyway.

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

NFSv4.2: Fix writeback races in nfs4_copy_file_range

We need to ensure that any writes to the destination file are serialised
with the copy, meaning that the writeback has to occur under the inode lock.

Also relax the writeback requirement on the source, and rely on the
stateid checking to tell us if the source rebooted. Add the helper
nfs_filemap_write_and_wait_range() to call pnfs_sync_inode() as
is appropriate for pNFS servers that may need a layoutcommit.

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

NFSv4.2: Fix a race in nfs42_proc_deallocate()

When punching holes in a file, we want to ensure the operation is
serialised w.r.t. other writes, meaning that we want to call
nfs_sync_inode() while holding the inode lock.

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

pnfs: only tear down lsegs that precede seqid in LAYOUTRETURN args

LAYOUTRETURN is "special" in that servers and clients are expected to
work with old stateids. When the client sends a LAYOUTRETURN with an old
stateid in it then the server is expected to only tear down layout
segments that were present when that seqid was current. Ensure that the
client handles its accounting accordingly.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Add COPY nfs operation

This adds the copy_range file_ops function pointer used by the
sys_copy_range() function call. This patch only implements sync copies,
so if an async copy happens we decode the stateid and ignore it.

Signed-off-by: Anna Schumaker <bjschuma@netapp.com>

nfs4: fix stateid handling for the NFS v4.2 operations

The newly added NFS v4.2 operations (ALLOCATE, DEALLOCATE, SEEK and CLONE)
use a helper called nfs42_set_rw_stateid to select a stateid that is sent
to the server. But they don't set the inode and state fields in the
nfs4_exception structure, and this don't partake in the stateid recovery
protocol. Because of this they will simply return errors insted of trying
to recover a stateid when the server return a BAD_STATEID error.

Additionally CLONE has the problem that it operates on two files and thus
two stateids, and thus needs to call the exception handler twice to
recover stateids.

While we're at it stop grabbing an addititional reference to the open
context in all these operations - having the file open guarantees that
the open context won't go away.

All this can be produces with the generic/168 and generic/170 tests in
xfstests which stress the CLONE stateid handling.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

wrappers for ->i_mutex access

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

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

NFS42: handle layoutstats stateid error

When server returns layoutstats stateid error, we should
invalidate client's layout so that next IO can trigger new
layoutget.

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

NFS: Properly set NFS v4.2 NFSDBG_FACILITY

NFS v4.2 operations can work outside of pNFS, so dprintk() output
shouldn't be placed under NFSDBG_PNFS.

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

nfs: pass on count for CLONE operations

Currently we pass uninitialized stack garbage in the count parameter.
The value is usually large enought to clone whole files and thus let
simple tests pass, but it makes the tests for range clones very unhappy.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs42: add CLONE proc functions

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

nfs: fix v4.2 SEEK on files over 2 gigs

We're incorrectly assigning a loff_t return to an int. If SEEK_HOLE or
SEEK_DATA returns an offset over 2^31 then the application will see a
weird lseek() result (usually -EIO).

Cc: stable@vger.kernel.org
Fixes: bdcc2cd14e4e "NFSv4.2: handle NFS-specific llseek errors"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFSv4.2: handle NFS-specific llseek errors

Handle NFS-specific llseek errors instead of letting them leak out to
userspace.

Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFSv4.2: LAYOUTSTATS is optional to implement

Make it so, by checking the return value for NFS4ERR_MOTSUPP and
caching the information as a server capability.

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

nfs42: serialize LAYOUTSTATS calls of the same file

There is no need to report concurrently.

Reviewed-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

pnfs: add pnfs_report_layoutstat helper function

Reviewed-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

pNFS: fill in nfs42_layoutstat_ops

Reviewed-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFSv.2/pnfs Add a LAYOUTSTATS rpc function

Reviewed-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFS: Reduce time spent holding the i_mutex during fallocate()

At the very least, we should not be taking the i_mutex until after
checking if the server even supports ALLOCATE or DEALLOCATE, allowing
v4.0 or v4.1 to exit without potentially waiting on a lock.

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

NFS: Don't zap caches on fallocate()

This patch adds a GETATTR to the end of ALLOCATE and DEALLOCATE
operations so we can set the updated inode size and change attribute
directly. DEALLOCATE will still need to release pagecache pages, so
nfs42_proc_deallocate() now calls truncate_pagecache_range() before
contacting the server.

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

nfs: Add DEALLOCATE support

This patch adds support for using the NFS v4.2 operation DEALLOCATE to
punch holes in a file.

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

nfs: Add ALLOCATE support

This patch adds support for using the NFS v4.2 operation ALLOCATE to
preallocate data in a file.

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

NFS: Use nfs_server_capable() for checknig NFS_CAP_SEEK

This should make the code easier to maintain in the future.

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

NFS: Implement SEEK

The SEEK operation is used when an application makes an lseek call with
either the SEEK_HOLE or SEEK_DATA flags set. I fall back on
nfs_file_llseek() if the server does not have SEEK support.

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