Commit Graph

495417 Commits

Author SHA1 Message Date
Trond Myklebust
4efdd92c92 SUNRPC: Remove TCP client connection reset hack
Instead we rely on SO_REUSEPORT to provide the reconnection semantics
that we need for NFSv2/v3.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:30 -05:00
Trond Myklebust
de84d89030 SUNRPC: TCP/UDP always close the old socket before reconnecting
It is not safe to call xs_reset_transport() from inside xs_udp_setup_socket()
or xs_tcp_setup_socket(), since they do not own the correct locks. Instead,
do it in xs_connect().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:30 -05:00
Trond Myklebust
718ba5b873 SUNRPC: Add helpers to prevent socket create from racing
The socket lock is currently held by the task that is requesting the
connection be established. While that is efficient in the case where
the connection happens quickly, it is racy in the case where it doesn't.
What we really want is for the connect helper to be able to block access
to the socket while it is being set up.

This patch does so by arranging to transfer the socket lock from the
task that is requesting the connect attempt, and then releasing that
lock once everything is done.
This scheme also gives us automatic protection against collisions with
the RPC close code, so we can kill the cancel_delayed_work_sync()
call in xs_close().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:29 -05:00
Trond Myklebust
6cc7e90836 SUNRPC: Ensure xs_reset_transport() resets the close connection flags
Otherwise, we may end up looping.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:28 -05:00
Trond Myklebust
76698b2358 SUNRPC: Do not clear the source port in xs_reset_transport
Now that we can reuse bound ports after a close, we never really want to
clear the transport's source port after it has been set. Doing so really
messes up the NFSv3 DRC on the server.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:28 -05:00
Trond Myklebust
3913c78c3a SUNRPC: Handle EADDRINUSE on connect
Now that we're setting SO_REUSEPORT, we still need to handle the
case where a connect() is attempted, but the old socket is still
lingering.
Essentially, all we want to do here is handle the error by waiting
a few seconds and then retrying.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:27 -05:00
Trond Myklebust
4dda9c8a5e SUNRPC: Set SO_REUSEPORT socket option for TCP connections
When using TCP, we need the ability to reuse port numbers after
a disconnection, so that the NFSv3 server knows that we're the same
client. Currently we use a hack to work around the TCP socket's
TIME_WAIT: we send an RST instead of closing, which doesn't
always work...
The SO_REUSEPORT option added in Linux 3.9 allows us to bind multiple
TCP connections to the same source address+port combination, and thus
to use ordinary TCP close() instead of the current hack.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 18:52:11 -05:00
Trond Myklebust
bc3203cdca NFS: RDMA Client Sparse Fixes
This patch fixes a sparse warning in the initial submission.
 
 Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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Merge tag 'nfs-rdma-for-3.20-part-2' of git://git.linux-nfs.org/projects/anna/nfs-rdma

NFS: RDMA Client Sparse Fixes

This patch fixes a sparse warning in the initial submission.

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

* tag 'nfs-rdma-for-3.20-part-2' of git://git.linux-nfs.org/projects/anna/nfs-rdma:
  xprtrdma: Address sparse complaint in rpcr_to_rdmar()
2015-02-08 10:37:34 -05:00
Trond Myklebust
4ef2e4f84c NFSv4.1: Fix pnfs_put_lseg races
pnfs_layoutreturn_free_lseg_async() can also race with inode put in
the general case. We can now fix this, and also simplify the code.

Cc: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-05 23:44:18 -05:00
Trond Myklebust
e4af440aaf NFSv4.1: pnfs_send_layoutreturn should use GFP_NOFS
In we want to be able to call pnfs_send_layoutreturn() from within the
writeback path, we really want it to use GFP_NOFS in order to prevent
recursion.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-05 22:16:50 -05:00
Trond Myklebust
5a0ec8acb9 NFSv4.1: Pin the inode and super block in asynchronous layoutreturns
If we're sending an asynchronous layoutreturn, then we need to ensure
that the inode and the super block remain pinned.

Cc: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Peng Tao <tao.peng@primarydata.com>
2015-02-05 22:16:45 -05:00
Trond Myklebust
472e259449 NFSv4.1: Pin the inode and super block in asynchronous layoutcommit
If we're sending an asynchronous layoutcommit, then we need to ensure
that the inode and the super block remain pinned.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Peng Tao <tao.peng@primarydata.com>
2015-02-05 22:16:33 -05:00
Trond Myklebust
ea7c38fef0 NFSv4: Ensure we reference the inode for return-on-close in delegreturn
If we have to do a return-on-close in the delegreturn code, then
we must ensure that the inode and super block remain referenced.

Cc: Peng Tao <tao.peng@primarydata.com>
Cc: stable@vger.kernel.org # 3.17.x
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Peng Tao <tao.peng@primarydata.com>
2015-02-05 21:31:06 -05:00
Chuck Lever
b625a61698 xprtrdma: Address sparse complaint in rpcr_to_rdmar()
With "make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__":

linux-2.6/net/sunrpc/xprtrdma/xprt_rdma.h:273:30: warning: incorrect
  type in initializer (different base types)
linux-2.6/net/sunrpc/xprtrdma/xprt_rdma.h:273:30: expected restricted
  __be32 [usertype] *buffer
linux-2.6/net/sunrpc/xprtrdma/xprt_rdma.h:273:30:    got unsigned int
  [usertype] *rq_buffer

As far as I can tell this is a false positive.

Reported-by: kbuild-all@01.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2015-02-05 15:38:29 -05:00
Trond Myklebust
6ae373394c NFSv4.1: Ask for no delegation on OPEN if using O_DIRECT
If we're using NFSv4.1, then we have the ability to let the server know
whether or not we believe that returning a delegation as part of our OPEN
request would be useful.
The feature needs to be used with care, since the client sending the request
doesn't necessarily know how other clients are using that file, and how
they may be affected by the delegation.
For this reason, our initial use of the feature will be to let the server
know when the client believes that handing out a delegation would not be
useful.
The first application for this function is when opening the file using
O_DIRECT.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-04 10:35:32 -05:00
Trond Myklebust
0e3b137fbf NFS: Add Anna Schumaker as co-maintainer for the NFS client
Anna has essentially been performing the duties of co-maintainer for
the past several years. In recognition of those efforts, I'd like to
add her to the maintainers file.

Cc: Anna Schumaker <anna.schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-04 10:35:31 -05:00
Trond Myklebust
03a9a42a1a SUNRPC: NULL utsname dereference on NFS umount during namespace cleanup
Fix an Oopsable condition when nsm_mon_unmon is called as part of the
namespace cleanup, which now apparently happens after the utsname
has been freed.

Link: http://lkml.kernel.org/r/20150125220604.090121ae@neptune.home
Reported-by: Bruno Prémont <bonbons@linux-vserver.org>
Cc: stable@vger.kernel.org # 3.18
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-03 16:40:17 -05:00
Trond Myklebust
e2c63e091e Merge branch 'flexfiles'
* flexfiles: (53 commits)
  pnfs: lookup new lseg at lseg boundary
  nfs41: .init_read and .init_write can be called with valid pg_lseg
  pnfs: Update documentation on the Layout Drivers
  pnfs/flexfiles: Add the FlexFile Layout Driver
  nfs: count DIO good bytes correctly with mirroring
  nfs41: wait for LAYOUTRETURN before retrying LAYOUTGET
  nfs: add a helper to set NFS_ODIRECT_RESCHED_WRITES to direct writes
  nfs41: add NFS_LAYOUT_RETRY_LAYOUTGET to layout header flags
  nfs/flexfiles: send layoutreturn before freeing lseg
  nfs41: introduce NFS_LAYOUT_RETURN_BEFORE_CLOSE
  nfs41: allow async version layoutreturn
  nfs41: add range to layoutreturn args
  pnfs: allow LD to ask to resend read through pnfs
  nfs: add nfs_pgio_current_mirror helper
  nfs: only reset desc->pg_mirror_idx when mirroring is supported
  nfs41: add a debug warning if we destroy an unempty layout
  pnfs: fail comparison when bucket verifier not set
  nfs: mirroring support for direct io
  nfs: add mirroring support to pgio layer
  pnfs: pass ds_commit_idx through the commit path
  ...

Conflicts:
	fs/nfs/pnfs.c
	fs/nfs/pnfs.h
2015-02-03 16:01:27 -05:00
Weston Andros Adamson
7c13789e3e pnfs: lookup new lseg at lseg boundary
Before mirroring support was added, the pageio descriptor's pg_lseg was
set to null when an RPC was sent. Because of this, pg_init was called
at lseg boundaries with pg_lseg = NULL, and it could be set to the new
lseg.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:54 -08:00
Peng Tao
cb5d04bc39 nfs41: .init_read and .init_write can be called with valid pg_lseg
With pgio refactoring in v3.15, .init_read and .init_write can be
called with valid pgio->pg_lseg. file layout was fixed at that time
by commit c6194271f (pnfs: filelayout: support non page aligned
layouts). But the generic helper still needs to be fixed.

Cc: stable@vger.kernel.org # 3.15+
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:53 -08:00
Tom Haynes
8f9cdcb26b pnfs: Update documentation on the Layout Drivers
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:53 -08:00
Tom Haynes
d67ae825a5 pnfs/flexfiles: Add the FlexFile Layout Driver
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: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
Signed-off-by: Tao Peng <bergwolf@primarydata.com>
2015-02-03 11:06:52 -08:00
Peng Tao
5fadeb47dc nfs: count DIO good bytes correctly with mirroring
When resending to MDS, we might resend multiple mirroring
requests to MDS. As a result, nfs_direct_good_bytes() ends
up counting bytes multiple times, causing application to
get wrong return results in read/write syscalls.

Fix it by tracking start of a dreq and checking the range of
pgio header.

Cc: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:52 -08:00
Peng Tao
aa8a45ee97 nfs41: wait for LAYOUTRETURN before retrying LAYOUTGET
Also take care to stop waiting if someone clears retry bit.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:51 -08:00
Peng Tao
012fa16dca nfs: add a helper to set NFS_ODIRECT_RESCHED_WRITES to direct writes
To allow pnfs LD to ask direct writes to be resend.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:51 -08:00
Peng Tao
c829013dca nfs41: add NFS_LAYOUT_RETRY_LAYOUTGET to layout header flags
Use it to indicate that LD wants to retry layoutget. LD can set
it whenever it wants the common pnfs code to return and retry
pnfs path through a new layout.

The bit gets cleared when client does a new layoutget, when client
closes the file (ROC case), or when kernel needs to evict the inode
(non-ROC case).

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:50 -08:00
Peng Tao
27b6f53987 nfs/flexfiles: send layoutreturn before freeing lseg
Otherwise we'll lose error tracking information when
encoding layoutreturn.

pnfs_put_lseg may be called from rpc callbacks. So we should not
call pnfs_send_layoutreturn directly because it can deadlock in
the rpc layer.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:50 -08:00
Peng Tao
193e3aa2cc nfs41: introduce NFS_LAYOUT_RETURN_BEFORE_CLOSE
When it is set, generic pnfs would try to send layoutreturn right
before last close/delegation_return regard less NFS_LAYOUT_ROC is
set or not. LD can then make sure layoutreturn is always sent
rather than being omitted.

The difference against NFS_LAYOUT_RETURN is that
NFS_LAYOUT_RETURN_BEFORE_CLOSE does not block usage of the layout so
LD can set it and expect generic layer to try pnfs path at the
same time.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:50 -08:00
Peng Tao
6c16605d6e nfs41: allow async version layoutreturn
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:49 -08:00
Peng Tao
15eb67c153 nfs41: add range to layoutreturn args
So that callers can specify which range to return.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:49 -08:00
Peng Tao
ceb11e13df pnfs: allow LD to ask to resend read through pnfs
If current IO cannot be completed due to some transient errors,
LD may want to ask generic layer to resend the request through
pnfs again.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:48 -08:00
Peng Tao
48d635f14a nfs: add nfs_pgio_current_mirror helper
Let it return current nfs_pgio_mirror in use depending on pg_mirror_count.
For read, we always use pg_mirrors[0], so this effectively gives us freedom
to use pg_mirror_idx to track the actual mirror to read from through out the
IO stack.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:48 -08:00
Peng Tao
47af81f295 nfs: only reset desc->pg_mirror_idx when mirroring is supported
so that we don't reset desc->pg_mirror_idx for read unnecessarily.
Remove WARN_ON_ONCE from __nfs_pageio_add_request to allow LD to
set pg_mirror_idx for read where pg_mirror_count is always 1.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:47 -08:00
Peng Tao
566f873763 nfs41: add a debug warning if we destroy an unempty layout
So that we can detect the case if some layout segments are still
pinned which is surely a bug that we need to fix.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:47 -08:00
Weston Andros Adamson
80c76fe314 pnfs: fail comparison when bucket verifier not set
This skips the WARN_ON_ONCE, but doesnt change behavior (the memcmp would
fail).

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:46 -08:00
Weston Andros Adamson
0a00b77b33 nfs: mirroring support for direct io
The current mirroring code only notices short writes to the first
mirror. This patch keeps per-mirror byte counts and only considers
a byte to be written once all mirrors report so.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:46 -08:00
Weston Andros Adamson
a7d42ddb30 nfs: add mirroring support to pgio layer
This patch adds mirrored write support to the pgio layer. The default
is to use one mirror, but pgio callers may define callbacks to change
this to any value up to the (arbitrarily selected) limit of 16.

The basic idea is to break out members of nfs_pageio_descriptor that cannot
be shared between mirrored DSes and put them in a new structure.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:45 -08:00
Weston Andros Adamson
b57ff1303a 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>
2015-02-03 11:06:45 -08:00
Weston Andros Adamson
6cccbb6f52 nfs: rename pgio header ds_idx to ds_commit_idx
'ds_commit_idx' is a better name - it is used to select the right
commit bucket for pnfs.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:44 -08:00
Weston Andros Adamson
309a1d65b1 nfs: handle overlapping reqs in lock_and_join
This is needed for mirrored DS support, where multuple requests
cover the same range.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:44 -08:00
Weston Andros Adamson
180bb5ec06 pnfs: release lseg in pnfs_generic_pg_cleanup
This is needed to support mirrored writes - the first write can't just
trash the lseg, we need to keep it around until all mirrors have
written.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:44 -08:00
Weston Andros Adamson
2176bf4269 nfs: introduce pg_cleanup op for pgio descriptors
Add a new operation to nfs_pageio_ops that is called on nfs_pageio_complete.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:43 -08:00
Peng Tao
c220106fb4 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
2015-02-03 11:06:43 -08:00
Peng Tao
e736a5b98c nfs41: clear NFS_LAYOUT_RETURN if layoutreturn is sent or failed to send
So that pnfs path is not disabled for ever.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:42 -08:00
Peng Tao
aa1e0e3a8e nfs41: send layoutreturn in last put_lseg
If current lseg is the last lseg marked with NFS_LSEG_LAYOUTRETURN,
send layoutreturn.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:42 -08:00
Peng Tao
ce6ab4f238 nfs41: don't use a layout if it is marked for returning
And if we are to return the same type of layouts, don't bother
sending more layoutgets.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:41 -08:00
Peng Tao
016256df3a nfs41: add a helper to mark layout for return
It marks all matching layout segments as NFS_LSEG_LAYOUTRETURN,
which is an indicator for pnfs_put_lseg() to send layoutreturn,
and also prevents pnfs_update_layout() from using the returning
segments. Once it is set, it never gets cleared.

It also sets proper io failure bit so that pnfs path can be retried
after PNFS_LAYOUTGET_RETRY_TIMEOUT second.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:41 -08:00
Peng Tao
f40eb5d044 nfs41: make a helper function to send layoutreturn
It allows to specify different iomode to return.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:41 -08:00
Peng Tao
4579d6b897 nfs41: pass iomode through layoutreturn args
So that it is possible to return a specific iomode layouts.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:40 -08:00
Peng Tao
aabff4ddca nfs: save server READ/WRITE/COMMIT status
Flexfiles layout would want to use them to report DS IO status.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:40 -08:00