In order to ensure atomicity of updates, we merge the old layout segments
into the new ones, and then invalidate the old ones.

Also ensure that we order the list of layout segments so that
RO segments are preferred over RW.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Allow advanced users to set the layoutstats timer in order to lengthen
or shorten the period between layoutstat transmissions to the server.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Keep the full list of mirrors in the struct nfs4_ff_layout_mirror so that
they can be shared among the layout segments that use them.
Also ensure that we send out only one copy of the layoutstats per mirror.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

When we start sharing mirrors between several lsegs, we won't be able to
keep it.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We do want to share mirrors between layout segments, so add a refcount
to enable that.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We do not want to update inode attributes with DS values.

Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Make sure that we also handle RPC level connection and protocol
negotiation errors.
Reported-by: NTom Haynes <loghyr@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We want to ensure that the stopwatches for the busy timer and the
aggregate timer are consistent. This means that they need to use
the same start/stop times.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Otherwise we break fstest case tests/read_write/mctime.t

Does files layout need the same fix as well?

Cc: stable@vger.kernel.org # v4.0+
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We already know that pg_lseg is NULL here.
Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Prevent a potential deadlock.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Turned out I misinterpreted the spec...

Cc: Tom Haynes <thomas.haynes@primarydata.com>
Reported-by: NJean Spector <jean@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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

hdr->good_bytes needs to be set to the length of the request, not
zero.

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

This patch ensures that we record the value of 'ffl_flags' from
the layout, and then checks for the presence of the
FF_FLAGS_NO_LAYOUTCOMMIT flag before deciding whether or not to
call pnfs_set_layoutcommit().

The effect is that servers now can decide whether or not they want
the client to call layoutcommit before returning a writeable layout.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

It looks as if xchg() and cmpxchg() are not available for 64-bit integers on sparc32:

> New breakage seen in linux-next today:
>
> ERROR: "__xchg_called_with_bad_pointer" [fs/nfs/flexfilelayout/nfs_layout_flexfiles.ko] undefined!
> ERROR: "__cmpxchg_called_with_bad_pointer" [fs/nfs/flexfilelayout/nfs_layout_flexfiles.ko] undefined!
> make[2]: *** [__modpost] Error 1
> make[1]: *** [modules] Error 2

Given that mirror ktime manipulation is already under mirror->lock, let's make use of the fact.
Reported-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

A ds can be associated with more than one mirror, but we currently skip
setting a mirror's credentials if we find that it's already set up with
a connected client.

The upshot is that we can end up sending DS writes with MDS credentials
instead of properly setting them up. Fix nfs4_ff_layout_prepare_ds to
always verify that the mirror's credentials are set up, even when we
have a DS that's already connected.
Reported-by: NTom Haynes <thomas.haynes@primarydata.com>
Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we have two tasks racing to update a mirror's credentials, then they
can end up leaking one (or more) sets of credentials. The first task
will set mirror->cred and then the second task will just overwrite it.

Use a cmpxchg to ensure that the creds are only set once. If we get to
the point where we would set mirror->cred and find that they're already
set, then we just release the creds that were just found.
Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

As a simple scheme, report every minute if IO is still going on.
Reviewed-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Reviewed-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

It fills in the generic part of LAYOUTSTATS call. One thing to note
is that we don't really track if IO is continuous or not. So just fake
to use the completed bytes for it.

Still missing flexfiles specific part, which will be included in the next patch.
Reviewed-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

So that we can report cumulative time since the beginning
of statistics collection of the layout.
Reviewed-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Reviewed-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Reviewed-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Use kernel.h macro definition.

Thanks to Julia Lawall for Coccinelle scripting support.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This file is only used internally to the NFS v4 module, so it doesn't
need to be in the global include path.  I also renamed it from
nfs_idmap.h to nfs4idmap.h to emphasize that it's an NFSv4-only include
file.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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: NTrond Myklebust <trond.myklebust@primarydata.com>

pnfs_set_layoutcommit() and pnfs_commit_set_layoutcommit() are 100% identical
except for the function arguments. Refactor to eliminate the difference.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Make it easier to grep for these functions by name.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Use of synchronize_rcu() when unmounting and potentially freeing a lot
of deviceids is problematic. There really is no reason why we can't just
use kfree_rcu() here.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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

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

Found by 0-DAY kernel test infrastructure:

fs/nfs/flexfilelayout/flexfilelayoutdev.c:520:13-16: ERROR: reference preceded by free on line 518
fs/nfs/flexfilelayout/flexfilelayoutdev.c:520:26-29: ERROR: reference preceded by free on line 518
fs/nfs/flexfilelayout/flexfilelayoutdev.c:520:39-42: ERROR: reference preceded by free on line 518
fs/nfs/flexfilelayout/flexfilelayoutdev.c:521:3-6: ERROR: reference preceded by free on line 518
Reported-by: NJulia Lawall <julia.lawall@lip6.fr>
Signed-off-by: NTom Haynes <loghyr@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The flexfile layout is a new layout that extends the
file layout. It is currently being drafted as a specification at
https://datatracker.ietf.org/doc/draft-ietf-nfsv4-layout-types/Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>
Signed-off-by: NTom Haynes <loghyr@primarydata.com>
Signed-off-by: NTao Peng <bergwolf@primarydata.com>