NFSv4.1/pnfs: fix NFS with TLS in pnfs

Currently, even though xprtsec=tls is specified and used for operations
to MDS, any operations that go to DS travel over unencrypted connection.
Or additionally, if more than 1 DS can serve the data, then trunked
connections are also done unencrypted.

IN GETDEVINCEINFO, we get an entry for the DS which carries a protocol
type (which is TCP), then nfs4_set_ds_client() gets called with TCP
instead of TCP with TLS.

Currently, each trunked connection is created and uses clp->cl_hostname
value which if TLS is used would get passed up in the handshake upcall,
but instead we need to pass in the appropriate trunked address value.

Fixes: c8407f2e560c ("NFS: Add an "xprtsec=" NFS mount option")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

pNFS: Fix assignment of xprtdata.cred

The comma at the end of the line was leftover from an earlier refactor
of the _nfs4_pnfs_v3_ds_connect() function. This is technically valid C,
so the compilers didn't catch it, but if I'm understanding how it works
correctly it assigns the return value of rpc_clnt_add_xprtr() to
xprtdata.cred.

Reported-by: Olga Kornievskaia <kolga@netapp.com>
Fixes: a12f996d3413 ("NFSv4/pNFS: Use connections to a DS that are all of the same protocol family")
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

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: Convert buffered writes to use folios

Mostly mechanical conversion of struct page and functions into struct
folio equivalents.
The lack of support for folios in write_cache_pages(), means we still
only support order 0 folio allocations. However the rest of the
writeback code should now be ready for order n > 0.

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

fs/nfs/pnfs_nfs.c: fix spelling typo and syntax error in comment

Fix spelling typo and syntax error in comment.

Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: k2ci <kernel-bot@kylinos.cn>
Signed-off-by: Jiangshan Yi <yijiangshan@kylinos.cn>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: nfsiod should not block forever in mempool_alloc()

The concern is that since nfsiod is sometimes required to kick off a
commit, it can get locked up waiting forever in mempool_alloc() instead
of failing gracefully and leaving the commit until later.

Try to allocate from the slab first, with GFP_KERNEL | __GFP_NORETRY,
then fall back to a non-blocking attempt to allocate from the memory
pool.

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

NFS: Fix up commit deadlocks

If O_DIRECT bumps the commit_info rpcs_out field, then that could lead
to fsync() hangs. The fix is to ensure that O_DIRECT calls
nfs_commit_end().

Fixes: 723c921e7dfc ("sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

pnfs/flexfiles: Fix misplaced barrier in nfs4_ff_layout_prepare_ds

_nfs4_pnfs_v3/v4_ds_connect do
some work
smp_wmb
ds->ds_clp = clp;

And nfs4_ff_layout_prepare_ds currently does
smp_rmb
if(ds->ds_clp)
...

This patch places the smp_rmb after the if. This ensures that following
reads only happen once nfs4_ff_layout_prepare_ds has checked that data
has been properly initialized.

Fixes: d67ae825a59d6 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Baptiste Lepers <baptiste.lepers@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4/pNFS: Return an error if _nfs4_pnfs_v3_ds_connect can't load NFSv3

Currently we fail to return an error if the NFSv3 module failed to load
when we're trying to connect to a pNFS data server.

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

NFSv4/pNFS: Don't call _nfs4_pnfs_v3_ds_connect multiple times

After we grab the lock in nfs4_pnfs_ds_connect(), there is no check for
whether or not ds->ds_clp has already been initialised, so we can end up
adding the same transports multiple times.

Fixes: fc821d59209d ("pnfs/NFSv4.1: Add multipath capabilities to pNFS flexfiles servers over NFSv3")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS/pNFS: Don't leak DS commits in pnfs_generic_retry_commit()

We must ensure that we pass a layout segment to nfs_retry_commit() when
we're cleaning up after pnfs_bucket_alloc_ds_commits(). Otherwise,
requests that should be committed to the DS will get committed to the
MDS.
Do so by ensuring that pnfs_bucket_get_committing() always tries to
return a layout segment when it returns a non-empty page list.

Fixes: c84bea59449a ("NFS/pNFS: Simplify bucket layout segment reference counting")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS/pNFS: Don't call pnfs_free_bucket_lseg() before removing the request

In pnfs_generic_clear_request_commit(), we try calling
pnfs_free_bucket_lseg() before we remove the request from the DS bucket.
That will always fail, since the point is to test for whether or not
that bucket is empty.

Fixes: c84bea59449a ("NFS/pNFS: Simplify bucket layout segment reference counting")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

pNFS: Clean up open coded xdr string decoding

Use the existing xdr_stream_decode_string_dup() to safely decode into
kmalloced strings.

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

NFSv4/pNFS: Store the transport type in struct nfs4_pnfs_ds_addr

We want to enable RDMA and UDP as valid transport methods if a
GETDEVICEINFO call specifies it. Do so by adding a parser for the
netid that translates it to an appropriate argument for the RPC
transport layer.

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

pNFS: Add helpers for allocation/free of struct nfs4_pnfs_ds_addr

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

NFSv4/pNFS: Use connections to a DS that are all of the same protocol family

If the pNFS metadata server advertises multiple addresses for the same
data server, we should try to connect to just one protocol family and
transport type on the assumption that homogeneity will improve performance.

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

NFS/pnfs: Don't use RPC_TASK_CRED_NOREF with pnfs

When we're doing pnfs then the credential being used for the RPC call
is not necessarily the same as the one used in the open context, so
don't use RPC_TASK_CRED_NOREF.

Fixes: 612965072020 ("NFSv4: Avoid referencing the cred unnecessarily during NFSv4 I/O")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

pNFS: Fix RCU lock leakage

Another brown paper bag moment. pnfs_alloc_ds_commits_list() is leaking
the RCU lock.

Fixes: a9901899b649 ("pNFS: Add infrastructure for cleaning up per-layout commit structures")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS/pNFS: Fix pnfs_layout_mark_request_commit() invalid layout segment handling

Fix up pnfs_layout_mark_request_commit() to alway reschedule the write
if the layout segment is invalid. Also minor cleanup.

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

NFS/pNFS: Simplify bucket layout segment reference counting

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

NFS/pNFS: Clean up pNFS commit operations

Move the pNFS commit related operations into a separate structure
that can be carried by the pnfs_ds_commit_info.

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

NFS: Remove bucket array from struct pnfs_ds_commit_info

Remove the unused bucket array in struct pnfs_ds_commit_info.

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

NFS/pNFS: Add a helper pnfs_generic_search_commit_reqs()

Lift filelayout_search_commit_reqs() into the generic pnfs/nfs code,
and add support for commit arrays.

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

pNFS: Enable per-layout segment commit structures

Enable adding and lookup of per-layout segment commits in filelayout
and flexfilelayout.

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

pNFS: Add infrastructure for cleaning up per-layout commit structures

Ensure that both the file and flexfiles layout types clean up when
freeing the layout segments.

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

pNFS: Support per-layout segment commits in pnfs_generic_commit_pagelist()

Add support for scanning the full list of per-layout segment commit
arrays to pnfs_generic_commit_pagelist().

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

pNFS: Support per-layout segment commits in pnfs_generic_recover_commit_reqs()

Add support for scanning the full list of per-layout segment commit
arrays to pnfs_generic_recover_commit_reqs().

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

NFSv4/pNFS: Scan the full list of commit arrays when committing

Add support for scanning the full list of per-layout segment commit
arrays to pnfs_generic_scan_commit_lists()

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

pNFS: Add a helper to allocate the array of buckets

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

NFS/pNFS: Refactor pnfs_generic_commit_pagelist()

Refactor pnfs_generic_commit_pagelist() to simplify the conversion
to layout segment based commit lists.

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

NFS/pnfs: Fix pnfs_generic_prepare_to_resend_writes()

Instead of making assumptions about the commit verifier contents, change
the commit code to ensure we always check that the verifier was set
by the XDR code.

Fixes: f54bcf2ecee9 ("pnfs: Prepare for flexfiles by pulling out common code")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

pNFS/flexfiles: Turn off soft RPC calls

The pNFS/flexfiles I/O requests are sent with the SOFTCONN flag set, so
they automatically time out if the connection breaks. It should
therefore not be necessary to have the soft flag set in addition.

Fixes: 5f01d9539496 ("nfs41: create NFSv3 DS connection if specified")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

treewide: Add SPDX license identifier for missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFS/NFSD/SUNRPC: replace generic creds with 'struct cred'.

SUNRPC has two sorts of credentials, both of which appear as
"struct rpc_cred".
There are "generic credentials" which are supplied by clients
such as NFS and passed in 'struct rpc_message' to indicate
which user should be used to authorize the request, and there
are low-level credentials such as AUTH_NULL, AUTH_UNIX, AUTH_GSS
which describe the credential to be sent over the wires.

This patch replaces all the generic credentials by 'struct cred'
pointers - the credential structure used throughout Linux.

For machine credentials, there is a special 'struct cred *' pointer
which is statically allocated and recognized where needed as
having a special meaning. A look-up of a low-level cred will
map this to a machine credential.

Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFSv4: Fix locking in pnfs_generic_recover_commit_reqs

The use of the inode->i_lock was converted to a mutex, but we forgot
to remove the old inode unlock/lock() pair that allowed the layout
segment to be put inside the loop.

Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Fixes: e824f99adaaf1 ("NFSv4: Use a mutex to protect the per-inode commit...")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API

The old wait_on_atomic_t() is going to get removed, use the more
flexible wait_var_event() API instead.

No change in functionality.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

fs, nfs: convert nfs4_pnfs_ds.ds_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 nfs4_pnfs_ds.ds_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: Remove pnfs_generic_transfer_commit_list()

It's pretty much a duplicate of nfs_scan_commit_list() that also
clears the PG_COMMIT_TO_DS flag.

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

NFS: nfs_lock_and_join_requests and nfs_scan_commit_list can deadlock

Since the commit list is not ordered, it is possible for nfs_scan_commit_list
to hold a request that nfs_lock_and_join_requests() is waiting for, while
at the same time trying to grab a request that nfs_lock_and_join_requests
already holds.

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

NFS: Wait for requests that are locked on the commit list

If a request is on the commit list, but is locked, we will currently skip
it, which can lead to livelocking when the commit count doesn't reduce
to zero.

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

NFSv4/pnfs: Replace pnfs_put_lseg_locked() with pnfs_put_lseg()

Now that we no longer hold the inode->i_lock when manipulating the
commit lists, it is safe to call pnfs_put_lseg() again.

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

NFSv4: Use a mutex to protect the per-inode commit lists

The commit lists can get very large, so using the inode->i_lock can
end up affecting general metadata performance.

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

Revert commit 722f0b891198 ("pNFS: Don't send COMMITs to the DSes if...")

Doing the test without taking any locks is racy, and so really it makes
more sense to do it in the flexfiles code (which is the only case that
cares).

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

NFS: Fix another COMMIT race in pNFS

We must make sure that cinfo->ds->ncommitting is in sync with the
commit list, since it is checked as part of pnfs_commit_list().

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

NFS: Fix a COMMIT race in pNFS

We must make sure that cinfo->ds->nwritten is in sync with the
commit list, since it is checked as part of pnfs_scan_commit_lists().

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

pNFS: Fix NULL dereference in pnfs_generic_alloc_ds_commits

Signed-off-by: Fred Isaman <fred.isaman@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

pNFS: Fix a typo in pnfs_generic_alloc_ds_commits

If the layout segment is invalid, we want to just resend the remaining
writes.

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

pNFS: Don't send COMMITs to the DSes if the server invalidated our layout

If the layout was invalidated, then assume we should requeue all the
pending writes for the DS in question.

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

pNFS: unexport nfs4_pnfs_v3_ds_connect_unload

It is not used outside the NFSv4 module.

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

NFS: fix usage of mempools.

When passed GFP flags that allow sleeping (such as
GFP_NOIO), mempool_alloc() will never return NULL, it will
wait until memory is available.

This means that we don't need to handle failure, but that we
do need to ensure one thread doesn't call mempool_alloc()
twice on the one pool without queuing or freeing the first
allocation. If multiple threads did this during times of
high memory pressure, the pool could be exhausted and a
deadlock could result.

pnfs_generic_alloc_ds_commits() attempts to allocate from
the nfs_commit_mempool while already holding an allocation
from that pool. This is not safe. So change
nfs_commitdata_alloc() to take a flag that indicates whether
failure is acceptable.

In pnfs_generic_alloc_ds_commits(), accept failure and
handle it as we currently do. Else where, do not accept
failure, and do not handle it.

Even when failure is acceptable, we want to succeed if
possible. That means both
- using an entry from the pool if there is one
- waiting for direct reclaim is there isn't.

We call mempool_alloc(GFP_NOWAIT) to achieve the first, then
kmem_cache_alloc(GFP_NOIO|__GFP_NORETRY) to achieve the
second. Each of these can fail, but together they do the
best they can without blocking indefinitely.

The objects returned by kmem_cache_alloc() will still be freed
by mempool_free(). This is safe as mempool_alloc() uses
exactly the same function to allocate objects (since the mempool
was created with mempool_create_slab_pool()). The object returned
by mempool_alloc() and kmem_cache_alloc() are indistinguishable
so mempool_free() will handle both identically, either adding to the
pool or calling kmem_cache_free().

Also, don't test for failure when allocating from
nfs_wdata_mempool.

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

pNFS/flexfiles: never nfs4_mark_deviceid_unavailable

The flexfiles layout should never mark a device unavailable.

Move nfs4_mark_deviceid_unavailable out of nfs4_pnfs_ds_connect and call
directly from files layout where it's still needed.

The flexfiles driver still handles marked devices in error paths, but will
now print a rate limited warning.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.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 pnfs data server multipath session trunking

Try all multipath addresses for a data server. The first address that
successfully connects and creates a session is the DS mount address.
All subsequent addresses are tested for session trunking and
added as aliases.

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

nfs4: flexfiles: respect noresvport when establishing connections to DSes

Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs4: clnt: respect noresvport when establishing connections to DSes

result:

$ mount -o vers=4.1 dcache-lab007:/ /pnfs
$ cp /etc/profile /pnfs
tcp 0 0 131.169.185.68:1005 131.169.191.141:32049 ESTABLISHED
tcp 0 0 131.169.185.68:751 131.169.191.144:2049 ESTABLISHED
$

$ mount -o vers=4.1,noresvport dcache-lab007:/ /pnfs
$ cp /etc/profile /pnfs
tcp 0 0 131.169.185.68:34894 131.169.191.141:32049 ESTABLISHED
tcp 0 0 131.169.185.68:35722 131.169.191.144:2049 ESTABLISHED
$

Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

pNFS: Files and flexfiles always need to commit before layoutcommit

So ensure that we mark the layout for commit once the write is done,
and then ensure that the commit to ds is finished before sending
layoutcommit.

Note that by doing this, we're able to optimise away the commit
for the case of servers that don't need layoutcommit in order to
return updated attributes.

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

pnfs_nfs: fix _cancel_empty_pagelist

pnfs_generic_commit_cancel_empty_pagelist calls nfs_commitdata_release,
but that is wrong: nfs_commitdata_release puts the open context, something
that isn't valid until nfs_init_commit is called, which is never the case
when pnfs_generic_commit_cancel_empty_pagelist is called.

This was introduced in "nfs: avoid race that crashes nfs_init_commit".

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

nfs: avoid race that crashes nfs_init_commit

Since the patch "NFS: Allow multiple commit requests in flight per file"
we can run multiple simultaneous commits on the same inode. This
introduced a race over collecting pages to commit that made it possible
to call nfs_init_commit() with an empty list - which causes crashes like
the one below.

The fix is to catch this race and avoid calling nfs_init_commit and
initiate_commit when there is no work to do.

Here is the crash:

[600522.076832] BUG: unable to handle kernel NULL pointer dereference at 0000000000000040
[600522.078475] IP: [<ffffffffa0479e72>] nfs_init_commit+0x22/0x130 [nfs]
[600522.078745] PGD 4272b1067 PUD 4272cb067 PMD 0
[600522.078972] Oops: 0000 [#1] SMP
[600522.079204] Modules linked in: nfsv3 nfs_layout_flexfiles rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache dcdbas ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw vmw_vsock_vmci_transport vsock bonding ipmi_devintf ipmi_msghandler coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel ppdev vmw_balloon parport_pc parport acpi_cpufreq vmw_vmci i2c_piix4 shpchp nfsd auth_rpcgss nfs_acl lockd grace sunrpc xfs libcrc32c vmwgfx drm_kms_helper ttm drm crc32c_intel serio_raw vmxnet3
[600522.081380] vmw_pvscsi ata_generic pata_acpi
[600522.081809] CPU: 3 PID: 15667 Comm: /usr/bin/python Not tainted 4.1.9-100.pd.88.el7.x86_64 #1
[600522.082281] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/30/2014
[600522.082814] task: ffff8800bbbfa780 ti: ffff88042ae84000 task.ti: ffff88042ae84000
[600522.083378] RIP: 0010:[<ffffffffa0479e72>] [<ffffffffa0479e72>] nfs_init_commit+0x22/0x130 [nfs]
[600522.083973] RSP: 0018:ffff88042ae87438 EFLAGS: 00010246
[600522.084571] RAX: 0000000000000000 RBX: ffff880003485e40 RCX: ffff88042ae87588
[600522.085188] RDX: 0000000000000000 RSI: ffff88042ae874b0 RDI: ffff880003485e40
[600522.085756] RBP: ffff88042ae87448 R08: ffff880003486010 R09: ffff88042ae874b0
[600522.086332] R10: 0000000000000000 R11: 0000000000000005 R12: ffff88042ae872d0
[600522.086905] R13: ffff88042ae874b0 R14: ffff880003485e40 R15: ffff88042704c840
[600522.087484] FS: 00007f4728ff2740(0000) GS:ffff88043fd80000(0000) knlGS:0000000000000000
[600522.088070] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[600522.088663] CR2: 0000000000000040 CR3: 000000042b6aa000 CR4: 00000000001406e0
[600522.089327] Stack:
[600522.089926] 0000000000000001 ffff88042ae87588 ffff88042ae874f8 ffffffffa04f09fa
[600522.090549] 0000000000017840 0000000000017840 ffff88042ae87588 ffff8803258d9930
[600522.091169] ffff88042ae87578 ffffffffa0563d80 0000000000000000 ffff88042704c840
[600522.091789] Call Trace:
[600522.092420] [<ffffffffa04f09fa>] pnfs_generic_commit_pagelist+0x1da/0x320 [nfsv4]
[600522.093052] [<ffffffffa0563d80>] ? ff_layout_commit_prepare_v3+0x30/0x30 [nfs_layout_flexfiles]
[600522.093696] [<ffffffffa0562645>] ff_layout_commit_pagelist+0x15/0x20 [nfs_layout_flexfiles]
[600522.094359] [<ffffffffa047bc78>] nfs_generic_commit_list+0xe8/0x120 [nfs]
[600522.095032] [<ffffffffa047bd6a>] nfs_commit_inode+0xba/0x110 [nfs]
[600522.095719] [<ffffffffa046ac54>] nfs_release_page+0x44/0xd0 [nfs]
[600522.096410] [<ffffffff811a8122>] try_to_release_page+0x32/0x50
[600522.097109] [<ffffffff811bd4f1>] shrink_page_list+0x961/0xb30
[600522.097812] [<ffffffff811bdced>] shrink_inactive_list+0x1cd/0x550
[600522.098530] [<ffffffff811bea65>] shrink_lruvec+0x635/0x840
[600522.099250] [<ffffffff811bed60>] shrink_zone+0xf0/0x2f0
[600522.099974] [<ffffffff811bf312>] do_try_to_free_pages+0x192/0x470
[600522.100709] [<ffffffff811bf6ca>] try_to_free_pages+0xda/0x170
[600522.101464] [<ffffffff811b2198>] __alloc_pages_nodemask+0x588/0x970
[600522.102235] [<ffffffff811fbbd5>] alloc_pages_vma+0xb5/0x230
[600522.103000] [<ffffffff813a1589>] ? cpumask_any_but+0x39/0x50
[600522.103774] [<ffffffff811d6115>] wp_page_copy.isra.55+0x95/0x490
[600522.104558] [<ffffffff810e3438>] ? __wake_up+0x48/0x60
[600522.105357] [<ffffffff811d7d3b>] do_wp_page+0xab/0x4f0
[600522.106137] [<ffffffff810a1bbb>] ? release_task+0x36b/0x470
[600522.106902] [<ffffffff8126dbd7>] ? eventfd_ctx_read+0x67/0x1c0
[600522.107659] [<ffffffff811da2a8>] handle_mm_fault+0xc78/0x1900
[600522.108431] [<ffffffff81067ef1>] __do_page_fault+0x181/0x420
[600522.109173] [<ffffffff811446a6>] ? __audit_syscall_exit+0x1e6/0x280
[600522.109893] [<ffffffff810681c0>] do_page_fault+0x30/0x80
[600522.110594] [<ffffffff81024f36>] ? syscall_trace_leave+0xc6/0x120
[600522.111288] [<ffffffff81790a58>] page_fault+0x28/0x30
[600522.111947] Code: 5d c3 0f 1f 80 00 00 00 00 0f 1f 44 00 00 55 4c 8d 87 d0 01 00 00 48 89 e5 53 48 89 fb 48 83 ec 08 4c 8b 0e 49 8b 41 18 4c 39 ce <48> 8b 40 40 4c 8b 50 30 74 24 48 8b 87 d0 01 00 00 48 8b 7e 08
[600522.113343] RIP [<ffffffffa0479e72>] nfs_init_commit+0x22/0x130 [nfs]
[600522.114003] RSP <ffff88042ae87438>
[600522.114636] CR2: 0000000000000040

Fixes: af7cf057 (NFS: Allow multiple commit requests in flight per file)
CC: stable@vger.kernel.org
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Save struct inode * inside nfs_commit_info to clarify usage of i_lock

Commit ea2cf22 created nfs_commit_info and saved &inode->i_lock inside
this NFS specific structure. This obscures the usage of i_lock.
Instead, save struct inode * so later it's clear the spinlock taken is
i_lock.

Should be no functional change.

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

pnfs/NFSv4.1: Add multipath capabilities to pNFS flexfiles servers over NFSv3

This adds multipathing to pNFS over NFSv3 as described in the flexfiles
draft spec.
Ideally, we'd like to do the same for pNFS files, but the NFSv4.1 protocol
requires a call to EXCHANGE_ID in order to test that the connection can do
session trunking.

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

NFSv4.1/pNFS: Don't queue up a new commit if the layout segment is invalid

If the layout segment is invalid, then we should not be adding more
write requests to the commit list. Instead, those writes should be
replayed after requesting a new layout.

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

NFS: Allow multiple commit requests in flight per file

Allow synchronous RPC calls to wait for pending RPC calls to finish,
but also allow asynchronous ones to just fire off another commit.

With this patch, the xfstests generic/074 test completes in 226s
instead of 242s

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

NFS41: fix list splice type

We want to move commiting pages to pages list instead.
Otherwise it causes pnfs small writes crash like:

[34560.037692] BUG: unable to handle kernel NULL pointer dereference at 0000000000000068
[34560.038557] IP: [<ffffffffa05423d6>] nfs_init_commit+0x26/0x130 [nfs]
[34560.039400] PGD 69f5a067 PUD 69f59067 PMD 0
[34560.040207] Oops: 0000 [#1] SMP
[34560.041014] Modules linked in: nfsv3(OE) nfs_layout_flexfiles(OE) nfsv4(OE) nfs(OE) fscache(E) rpcsec_gss_krb5(E) xt_addrtype(E) xt_conntrack(E) ipt_MASQUERADE(E) nf_nat_masquerade_ipv4(E) iptable_nat(E) nf_conntrack_ipv4(E) nf_defrag_ipv4(E) nf_nat_ipv4(E) iptable_filter(E) ip_tables(E) x_tables(E) nf_nat(E) nf_conntrack(E) bridge(E) stp(E) llc(E) dm_thin_pool(E) dm_persistent_data(E) dm_bio_prison(E) dm_bufio(E) ppdev(E) vmw_balloon(E) coretemp(E) crc32_pclmul(E) ghash_clmulni_intel(E) aesni_intel(E) aes_x86_64(E) glue_helper(E) lrw(E) gf128mul(E) ablk_helper(E) cryptd(E) psmouse(E) serio_raw(E) vmw_vmci(E) i2c_piix4(E) shpchp(E) parport_pc(E) parport(E) mac_hid(E) nfsd(E) auth_rpcgss(E) nfs_acl(E) lockd(E) grace(E) sunrpc(E) xfs(E) libcrc32c(E) hid_generic(E) usbhid(E) hid(E) e1000(E) mptspi(E)
[34560.045106] mptscsih(E) mptbase(E) vmwgfx(E) drm_kms_helper(E) ttm(E) drm(E) autofs4(E) [last unloaded: fscache]
[34560.045897] CPU: 0 PID: 130543 Comm: bash Tainted: G OE 4.2.0-rc5-dp-00057-gf993a93 #11
[34560.046699] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014
[34560.047525] task: ffff880031b0a980 ti: ffff880045fec000 task.ti: ffff880045fec000
[34560.048264] RIP: 0010:[<ffffffffa05423d6>] [<ffffffffa05423d6>] nfs_init_commit+0x26/0x130 [nfs]
[34560.049000] RSP: 0018:ffff880045fefc18 EFLAGS: 00010246
[34560.049717] RAX: 0000000000000000 RBX: ffff8800208fbc80 RCX: ffff880045fefd50
[34560.050396] RDX: ffff880031c19ec0 RSI: ffff880045fefc88 RDI: ffff8800208fbc80
[34560.051041] RBP: ffff880045fefc28 R08: ffff8800208fbe68 R09: ffff880045fefc88
[34560.051666] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880045fefc78
[34560.052247] R13: ffff880045fefc88 R14: ffff880045fefa90 R15: ffff880045fefd50
[34560.052825] FS: 00007fa02d58c740(0000) GS:ffff88006d600000(0000) knlGS:0000000000000000
[34560.053410] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[34560.053992] CR2: 0000000000000068 CR3: 000000003b37a000 CR4: 00000000001406f0
[34560.054615] Stack:
[34560.055200] ffff8800208fbc80 ffff8800208fbc80 ffff880045fefcc8 ffffffffa05c1a5b
[34560.055800] ffff880045fefcc8 ffff880045fefd50 0000000045fefcb8 ffff880045fefd40
[34560.056418] ffff8800420608e0 ffffffffa04f3910 0000000100000001 ffff880045fefd50
[34560.057013] Call Trace:
[34560.057672] [<ffffffffa05c1a5b>] pnfs_generic_commit_pagelist+0x1cb/0x300 [nfsv4]
[34560.058277] [<ffffffffa04f3910>] ? ff_layout_commit_pagelist+0x20/0x20 [nfs_layout_flexfiles]
[34560.058907] [<ffffffffa04f3905>] ff_layout_commit_pagelist+0x15/0x20 [nfs_layout_flexfiles]
[34560.059557] [<ffffffffa0543fc1>] nfs_generic_commit_list+0xb1/0xf0 [nfs]
[34560.060214] [<ffffffffa0543e47>] ? nfs_scan_commit+0x37/0xa0 [nfs]
[34560.060825] [<ffffffffa0544081>] nfs_commit_inode+0x81/0x150 [nfs]
[34560.061432] [<ffffffffa05443ae>] nfs_wb_all+0x1ae/0x400 [nfs]
[34560.062035] [<ffffffffa05380ad>] nfs_getattr+0x33d/0x510 [nfs]
[34560.062630] [<ffffffff8122499c>] vfs_getattr_nosec+0x2c/0x40
[34560.063223] [<ffffffff81224a66>] vfs_getattr+0x26/0x30
[34560.063818] [<ffffffff81224b35>] vfs_fstatat+0x65/0xa0
[34560.064413] [<ffffffff81224f3f>] SYSC_newstat+0x1f/0x40
[34560.065016] [<ffffffff8102b176>] ? do_audit_syscall_entry+0x66/0x70
[34560.065626] [<ffffffff8102c773>] ? syscall_trace_enter_phase1+0x113/0x170
[34560.066245] [<ffffffff81003017>] ? trace_hardirqs_on_thunk+0x17/0x19
[34560.066868] [<ffffffff812251ae>] SyS_newstat+0xe/0x10
[34560.067533] [<ffffffff817a5df2>] entry_SYSCALL_64_fastpath+0x16/0x7a
[34560.068173] Code: 0f 1f 44 00 00 0f 1f 44 00 00 55 4c 8d 87 e8 01 00 00 48 89 e5 53 48 89 fb 48 83 ec 08 4c 8b 0e 49 8b 41 18 4c 39 ce 48 8b 40 40 <4c> 8b 50 68 74 24 48 8b 87 e8 01 00 00 48 8b 7e 08 4d 89 41 08
[34560.069609] RIP [<ffffffffa05423d6>] nfs_init_commit+0x26/0x130 [nfs]
[34560.070295] RSP <ffff880045fefc18>
[34560.071008] CR2: 0000000000000068
[34560.073207] ---[ end trace f85f873260977406 ]---

[fixes 27571297a7e(pNFS: Tighten up locking around DS commit buckets)]
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFSv4.1/pNFS: Fix borken function _same_data_server_addrs_locked()

- Switch back to using list_for_each_entry(). Fixes an incorrect test
for list NULL termination.
- Do not assume that lists are sorted.
- Finally, consider an existing entry to match if it consists of a subset
of the addresses in the new entry.

Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

pNFS: Tighten up locking around DS commit buckets

I'm not aware of any bugreports around this issue, but the locking
around the pnfs_commit_bucket is inconsistent at best. This patch
tightens it up by ensuring that the 'bucket->committing' list is always
changed atomically w.r.t. the 'bucket->clseg' layout segment tracking.

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

NFSv4.1/pnfs: Fix atomicity of commit list updates

pnfs_layout_mark_request_commit() needs to ensure that it adds the
request to the commit list atomically with all the other updates
in order to prevent corruption to buckets[ds_commit_idx].wlseg
due to races with pnfs_generic_clear_request_commit().

Fixes: 338d00cfef07d ("pnfs: Refactor the *_layout_mark_request_commit...")
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

NFSv4.1/pnfs: Separate out metadata and data consistency for pNFS

The LAYOUTCOMMIT operation means different things to different layout types.
For blocks and objects, it is both a data and metadata consistency operation.
For files and flexfiles, it is only a metadata consistency operation.

This patch separates out the 2 cases, allowing the files/flexfiles layout
drivers to optimise away the data consistency calls to layoutcommit.

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

nfs: do not export discarded symbols

The function nfs4_pnfs_v3_ds_connect_unload is exported so it can be
used by other modules, but is also marked '__exit' and will be
discarded when built into the kernel, as pointed out by this
linker error:

`nfs4_pnfs_v3_ds_connect_unload' referenced in section `___ksymtab_gpl+nfs4_pnfs_v3_ds_connect_unload' of fs/built-in.o: defined in discarded section `.exit.text' of fs/built-in.o

This removes the __exit annotation to make it safe to call this function.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 5f01d9539496 ("nfs41: create NFSv3 DS connection if specified")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

pnfs: Refactor the *_layout_mark_request_commit to use pnfs_layout_mark_request_commit

The File Layout's filelayout_mark_request_commit() is almost the
Flex File Layout's ff_layout_mark_request_commit(). And that can
be reduced by calling into nfs_request_add_commit_list().

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

pnfs: pass ds_commit_idx through the commit path

Pass ds_commit_idx through the nfs commit path. It's used to select
the commit bucket when using pnfs and is ignored when not using pnfs.
Several functions had to be changed: nfs_retry_commit,
nfs_mark_request_commit, pnfs_mark_request_commit and the pnfs layout
driver .mark_request_commit functions.

Signed-off-by: Tom Haynes <loghyr@primarydata.com>

nfs/filelayout: use pnfs_error_mark_layout_for_return

Instead of calling layoutreturn directly, call pnfs_error_mark_layout_for_return
to mark layouts for return and let generic code return layout when
layout segments are freed.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

Conflicts:
fs/nfs/filelayout/filelayout.c

nfs: allow different protocol in nfs_initiate_commit

pnfs flexfile layout client may want to use NFSv3 ops rather
than the default MDS v4 ops.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

nfs41: create NFSv3 DS connection if specified

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

nfs41: allow LD to choose DS connection version/minor_version

flexfile layout may need to set such when making DS connections.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

nfs41: allow LD to choose DS connection auth flavor

flexfile layout may use different auth flavor as specified by MDS.

Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

nfs41: pull nfs4_ds_connect from file layout to generic pnfs

It can be reused by flexfiles layout client.

Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

nfs41: pull decode_ds_addr from file layout to generic pnfs

It can be reused by flexfile layout.

Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

nfs41: pull data server cache from file layout to generic pnfs

Also pull nfs4_pnfs_ds_addr and nfs4_pnfs_ds to generic pnfs.

They can all be reused by flexfile layout as well.

Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

pnfs: Do not grab the commit_info lock twice when rescheduling writes

Acked-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>

pnfs: Prepare for flexfiles by pulling out common code

The flexfilelayout driver will share some common code
with the filelayout driver. This set of changes refactors
that common code out to avoid any module depenencies.

Signed-off-by: Tom Haynes <loghyr@primarydata.com>