Commit graph

1208 commits

Author SHA1 Message Date
Chuck Lever
c35ca60d49 xprtrdma: Delete rpcrdma_recv_buffer_put()
Clean up: The name recv_buffer_put() is a vestige of older code,
and the function is just a wrapper for the newer rpcrdma_rep_put().
In most of the existing call sites, a pointer to the owning
rpcrdma_buffer is already available.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-26 09:24:12 -04:00
Chuck Lever
35d8b10a25 xprtrdma: Fix cwnd update ordering
After a reconnect, the reply handler is opening the cwnd (and thus
enabling more RPC Calls to be sent) /before/ rpcrdma_post_recvs()
can post enough Receive WRs to receive their replies. This causes an
RNR and the new connection is lost immediately.

The race is most clearly exposed when KASAN and disconnect injection
are enabled. This slows down rpcrdma_rep_create() enough to allow
the send side to post a bunch of RPC Calls before the Receive
completion handler can invoke ib_post_recv().

Fixes: 2ae50ad68c ("xprtrdma: Close window between waking RPC senders and posting Receives")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-26 09:24:05 -04:00
Chuck Lever
9e3ca33b62 xprtrdma: Improve locking around rpcrdma_rep creation
Defensive clean up: Protect the rb_all_reps list during rep
creation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-26 09:23:40 -04:00
Chuck Lever
8b5292be68 xprtrdma: Improve commentary around rpcrdma_reps_unmap()
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-26 09:23:19 -04:00
Chuck Lever
eaf86e8cc8 xprtrdma: Improve locking around rpcrdma_rep destruction
Currently rpcrdma_reps_destroy() assumes that, at transport
tear-down, the content of the rb_free_reps list is the same as the
content of the rb_all_reps list. Although that is usually true,
using the rb_all_reps list should be more reliable because of
the way it's managed. And, rpcrdma_reps_unmap() uses rb_all_reps;
these two functions should both traverse the "all" list.

Ensure that all rpcrdma_reps are always destroyed whether they are
on the rep free list or not.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-26 09:22:29 -04:00
Chuck Lever
5030c9a938 xprtrdma: Put flushed Receives on free list instead of destroying them
Defer destruction of an rpcrdma_rep until transport tear-down to
preserve the rb_all_reps list while Receives flush.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-26 09:21:49 -04:00
Chuck Lever
15788d1d10 xprtrdma: Do not refresh Receive Queue while it is draining
Currently the Receive completion handler refreshes the Receive Queue
whenever a successful Receive completion occurs.

On disconnect, xprtrdma drains the Receive Queue. The first few
Receive completions after a disconnect are typically successful,
until the first flushed Receive.

This means the Receive completion handler continues to post more
Receive WRs after the drain sentinel has been posted. The late-
posted Receives flush after the drain sentinel has completed,
leading to a crash later in rpcrdma_xprt_disconnect().

To prevent this crash, xprtrdma has to ensure that the Receive
handler stops posting Receives before ib_drain_rq() posts its
drain sentinel.

Suggested-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-26 09:21:44 -04:00
Chuck Lever
32e6b68167 xprtrdma: Avoid Receive Queue wrapping
Commit e340c2d6ef ("xprtrdma: Reduce the doorbell rate (Receive)")
increased the number of Receive WRs that are posted by the client,
but did not increase the size of the Receive Queue allocated during
transport set-up.

This is usually not an issue because RPCRDMA_BACKWARD_WRS is defined
as (32) when SUNRPC_BACKCHANNEL is defined. In cases where it isn't,
there is a real risk of Receive Queue wrapping.

Fixes: e340c2d6ef ("xprtrdma: Reduce the doorbell rate (Receive)")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-26 09:21:36 -04:00
Chuck Lever
8727f78855 svcrdma: Pass a useful error code to the send_err tracepoint
Capture error codes in @ret, which is passed to the send_err
tracepoint, so that they can be logged when something goes awry.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-04-14 12:09:27 -04:00
Chuck Lever
c7731d5e05 svcrdma: Rename goto labels in svc_rdma_sendto()
Clean up: Make the goto labels consistent with other similar
functions.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-04-14 12:09:27 -04:00
Chuck Lever
351461f332 svcrdma: Don't leak send_ctxt on Send errors
Address a rare send_ctxt leak in the svc_rdma_sendto() error paths.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-04-14 12:09:27 -04:00
Chuck Lever
7638e0bfae SUNRPC: Move fault injection call sites
I've hit some crashes that occur in the xprt_rdma_inject_disconnect
path. It appears that, for some provides, rdma_disconnect() can
take so long that the transport can disconnect and release its
hardware resources while rdma_disconnect() is still running,
resulting in a UAF in the provider.

The transport's fault injection method may depend on the stability
of transport data structures. That means it needs to be invoked
only from contexts that hold the transport write lock.

Fixes: 4a06825839 ("SUNRPC: Transport fault injection")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-14 09:36:29 -04:00
Chuck Lever
e3eded5e81 svcrdma: Clean up dto_q critical section in svc_rdma_recvfrom()
This, to me, seems less cluttered and less redundant. I was hoping
it could help reduce lock contention on the dto_q lock by reducing
the size of the critical section, but alas, the only improvement is
readability.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-31 15:58:48 -04:00
Chuck Lever
5533c4f4b9 svcrdma: Remove svc_rdma_recv_ctxt::rc_pages and ::rc_arg
These fields are no longer used.

The size of struct svc_rdma_recv_ctxt is now less than 300 bytes on
x86_64, down from 2440 bytes.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-31 15:57:48 -04:00
Chuck Lever
9af723be86 svcrdma: Remove sc_read_complete_q
Now that svc_rdma_recvfrom() waits for Read completion,
sc_read_complete_q is no longer used.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-31 15:57:48 -04:00
Chuck Lever
7d81ee8722 svcrdma: Single-stage RDMA Read
Currently the generic RPC server layer calls svc_rdma_recvfrom()
twice to retrieve an RPC message that uses Read chunks. I'm not
exactly sure why this design was chosen originally.

Instead, let's wait for the Read chunk completion inline in the
first call to svc_rdma_recvfrom().

The goal is to eliminate some page allocator churn.
rdma_read_complete() replaces pages in the second svc_rqst by
calling put_page() repeatedly while the upper layer waits for the
request to be constructed, which adds unnecessary NFS WRITE round-
trip latency.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
2021-03-31 15:57:39 -04:00
Chuck Lever
82011c80b3 SUNRPC: Move svc_xprt_received() call sites
Currently, XPT_BUSY is not cleared until xpo_recvfrom returns.
That effectively blocks the receipt and handling of the next RPC
message until the current one has been taken off the transport.
This strict ordering is a requirement for socket transports.

For our kernel RPC/RDMA transport implementation, however, dequeuing
an ingress message is nothing more than a list_del(). The transport
can safely be marked un-busy as soon as that is done.

To keep the changes simpler, this patch just moves the
svc_xprt_received() call site from svc_handle_xprt() into the
transports, so that the actual optimization can be done in a
subsequent patch.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 13:22:13 -04:00
Chuck Lever
cc93ce9529 svcrdma: Retain the page backing rq_res.head[0].iov_base
svc_rdma_sendto() now waits for the NIC hardware to finish with
the pages backing rq_res. We still have to release the page array
in some cases, but now it's always safe to immediately re-use the
page backing rq_res's head buffer.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 13:22:13 -04:00
Chuck Lever
579900670a svcrdma: Remove unused sc_pages field
Clean up. This significantly reduces the size of struct
svc_rdma_send_ctxt.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 13:22:13 -04:00
Chuck Lever
2a1e4f21d8 svcrdma: Normalize Send page handling
Currently svc_rdma_sendto() migrates xdr_buf pages into a separate
page list and NULLs out a bunch of entries in rq_pages while the
pages are under I/O. The Send completion handler then frees those
pages later.

Instead, let's wait for the Send completion, then handle page
releasing in the nfsd thread. I'd like to avoid the cost of 250+
put_page() calls in the Send completion handler, which is single-
threaded.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 13:22:13 -04:00
Chuck Lever
e844d307d4 svcrdma: Add a "deferred close" helper
Refactor a bit of commonly used logic so that every site that wants
a close deferred to an nfsd thread does all the right things
(set_bit(XPT_CLOSE) then enqueue).

Also, once XPT_CLOSE is set on a transport, it is never cleared. If
XPT_CLOSE is already set, then the close is already being handled
and the enqueue can be skipped.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 13:22:13 -04:00
Chuck Lever
c558d47596 svcrdma: Maintain a Receive water mark
Post more Receives when the number of pending Receives drops below
a water mark. The batch mechanism is disabled if the underlying
device cannot support a reasonably-sized Receive Queue.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 13:22:13 -04:00
Chuck Lever
7b748c30cc svcrdma: Use svc_rdma_refresh_recvs() in wc_receive
Replace svc_rdma_post_recv() with the new batch receive mechanism.
For the moment it is posting just a single Receive WR at a time,
so no change in behavior is expected.

Since svc_rdma_wc_receive() was the last call site for
svc_rdma_post_recv(), it is removed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 13:22:13 -04:00
Chuck Lever
77f0a2aa5c svcrdma: Add a batch Receive posting mechanism
Introduce a server-side mechanism similar to commit e340c2d6ef
("xprtrdma: Reduce the doorbell rate (Receive)") to post Receive
WRs in batch. Its first consumer is svc_rdma_post_recvs(), which
posts the initial set of Receive WRs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 13:22:13 -04:00
Chuck Lever
c6b7ed8f94 svcrdma: Remove stale comment for svc_rdma_wc_receive()
xprt pinning was removed in commit 365e9992b9 ("svcrdma: Remove
transport reference counting"), but this comment was not updated
to reflect that change.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 10:19:05 -04:00
Chuck Lever
270f25edcc svcrdma: Provide an explanatory comment in CMA event handler
Clean up: explain why svc_xprt_enqueue() is invoked in the event
handler even though no xpt_flags bits are toggled here.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 10:19:05 -04:00
Chuck Lever
072db263e1 svcrdma: RPCDBG_FACILITY is no longer used
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22 10:19:05 -04:00
Chuck Lever
bade4be69a svcrdma: Revert "svcrdma: Reduce Receive doorbell rate"
I tested commit 43042b90ca ("svcrdma: Reduce Receive doorbell
rate") with mlx4 (IB) and software iWARP and didn't find any
issues. However, I recently got my hardware iWARP setup back on
line (FastLinQ) and it's crashing hard on this commit (confirmed
via bisect).

The failure mode is complex.
 - After a connection is established, the first Receive completes
   normally.
 - But the second and third Receives have garbage in their Receive
   buffers. The server responds with ERR_VERS as a result.
 - When the client tears down the connection to retry, a couple
   of posted Receives flush twice, and that corrupts the recv_ctxt
   free list.
 - __svc_rdma_free then faults or loops infinitely while destroying
   the xprt's recv_ctxts.

Since 43042b90ca ("svcrdma: Reduce Receive doorbell rate") does
not fix a bug but is a scalability enhancement, it's safe and
appropriate to revert it while working on a replacement.

Fixes: 43042b90ca ("svcrdma: Reduce Receive doorbell rate")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-11 15:26:07 -05:00
Timo Rothenpieler
6820bf7786 svcrdma: disable timeouts on rdma backchannel
This brings it in line with the regular tcp backchannel, which also has
all those timeouts disabled.

Prevents the backchannel from timing out, getting some async operations
like server side copying getting stuck indefinitely on the client side.

Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org>
Fixes: 5d252f90a8 ("svcrdma: Add class for RDMA backwards direction transport")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-06 16:41:48 -05:00
Linus Torvalds
1c9077cdec NFS Client Updates for Linux 5.12
- New Features:
   - Support for eager writes, and the write=eager and write=wait mount options
 
 - Other Bugfixes and Cleanups:
   - Fix typos in some comments
   - Fix up fall-through warnings for Clang
   - Cleanups to the NFS readpage codepath
   - Remove FMR support in rpcrdma_convert_iovs()
   - Various other cleanups to xprtrdma
   - Fix xprtrdma pad optimization for servers that don't support RFC 8797
   - Improvements to rpcrdma tracepoints
   - Fix up nfs4_bitmask_adjust()
   - Optimize sparse writes past the end of files
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Merge tag 'nfs-for-5.12-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS Client Updates from Anna Schumaker:
 "New Features:
   - Support for eager writes, and the write=eager and write=wait mount
     options

- Other Bugfixes and Cleanups:
   - Fix typos in some comments
   - Fix up fall-through warnings for Clang
   - Cleanups to the NFS readpage codepath
   - Remove FMR support in rpcrdma_convert_iovs()
   - Various other cleanups to xprtrdma
   - Fix xprtrdma pad optimization for servers that don't support
     RFC 8797
   - Improvements to rpcrdma tracepoints
   - Fix up nfs4_bitmask_adjust()
   - Optimize sparse writes past the end of files"

* tag 'nfs-for-5.12-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (27 commits)
  NFS: Support the '-owrite=' option in /proc/self/mounts and mountinfo
  NFS: Set the stable writes flag when initialising the super block
  NFS: Add mount options supporting eager writes
  NFS: Add support for eager writes
  NFS: 'flags' field should be unsigned in struct nfs_server
  NFS: Don't set NFS_INO_INVALID_XATTR if there is no xattr cache
  NFS: Always clear an invalid mapping when attempting a buffered write
  NFS: Optimise sparse writes past the end of file
  NFS: Fix documenting comment for nfs_revalidate_file_size()
  NFSv4: Fixes for nfs4_bitmask_adjust()
  xprtrdma: Clean up rpcrdma_prepare_readch()
  rpcrdma: Capture bytes received in Receive completion tracepoints
  xprtrdma: Pad optimization, revisited
  rpcrdma: Fix comments about reverse-direction operation
  xprtrdma: Refactor invocations of offset_in_page()
  xprtrdma: Simplify rpcrdma_convert_kvec() and frwr_map()
  xprtrdma: Remove FMR support in rpcrdma_convert_iovs()
  NFS: Add nfs_pageio_complete_read() and remove nfs_readpage_async()
  NFS: Call readpage_async_filler() from nfs_readpage_async()
  NFS: Refactor nfs_readpage() and nfs_readpage_async() to use nfs_readdesc
  ...
2021-02-26 09:17:24 -08:00
Linus Torvalds
7c70f3a748 Optimization:
- Cork the socket while there are queued replies
 
 Fixes:
 
 - DRC shutdown ordering
 - svc_rdma_accept() lockdep splat
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Merge tag 'nfsd-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull more nfsd updates from Chuck Lever:
 "Here are a few additional NFSD commits for the merge window:

 Optimization:
   - Cork the socket while there are queued replies

  Fixes:
   - DRC shutdown ordering
   - svc_rdma_accept() lockdep splat"

* tag 'nfsd-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  SUNRPC: Further clean up svc_tcp_sendmsg()
  SUNRPC: Remove redundant socket flags from svc_tcp_sendmsg()
  SUNRPC: Use TCP_CORK to optimise send performance on the server
  svcrdma: Hold private mutex while invoking rdma_accept()
  nfsd: register pernet ops last, unregister first
2021-02-22 13:29:55 -08:00
Chuck Lever
0ac24c320c svcrdma: Hold private mutex while invoking rdma_accept()
RDMA core mutex locking was restructured by commit d114c6feed
("RDMA/cma: Add missing locking to rdma_accept()") [Aug 2020]. When
lock debugging is enabled, the RPC/RDMA server trips over the new
lockdep assertion in rdma_accept() because it doesn't call
rdma_accept() from its CM event handler.

As a temporary fix, have svc_rdma_accept() take the handler_mutex
explicitly. In the meantime, let's consider how to restructure the
RPC/RDMA transport to invoke rdma_accept() from the proper context.

Calls to svc_rdma_accept() are serialized with calls to
svc_rdma_free() by the generic RPC server layer.

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/linux-rdma/20210209154014.GO4247@nvidia.com/
Fixes: d114c6feed ("RDMA/cma: Add missing locking to rdma_accept()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-02-15 10:45:00 -05:00
Chuck Lever
586a0787ce xprtrdma: Clean up rpcrdma_prepare_readch()
Since commit 9ed5af268e ("SUNRPC: Clean up the handling of page
padding in rpc_prepare_reply_pages()") [Dec 2020] the NFS client
passes payload data to the transport with the padding in xdr->pages
instead of in the send buffer's tail kvec. There's no need for the
extra logic to advance the base of the tail kvec because the upper
layer no longer places XDR padding there.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-02-05 15:54:03 -05:00
Chuck Lever
2324fbedc2 xprtrdma: Pad optimization, revisited
The NetApp Linux team discovered that with NFS/RDMA servers that do
not support RFC 8797, the Linux client is forming NFSv4.x WRITE
requests incorrectly.

In this case, the Linux NFS client disables implicit chunk round-up
for odd-length Read and Write chunks. The goal was to support old
servers that needed that padding to be sent explicitly by clients.

In that case the Linux NFS included the tail kvec in the Read chunk,
since the tail contains any needed padding. That meant a separate
memory registration is needed for the tail kvec, adding to the cost
of forming such requests. To avoid that cost for a mere 3 bytes of
zeroes that are always ignored by receivers, we try to use implicit
roundup when possible.

For NFSv4.x, the tail kvec also sometimes contains a trailing
GETATTR operation. The Linux NFS client unintentionally includes
that GETATTR operation in the Read chunk as well as inline.

The fix is simply to /never/ include the tail kvec when forming a
data payload Read chunk. The padding is thus now always present.

Note that since commit 9ed5af268e ("SUNRPC: Clean up the handling
of page padding in rpc_prepare_reply_pages()") [Dec 2020] the NFS
client passes payload data to the transport with the padding in
xdr->pages instead of in the send buffer's tail kvec. So now the
Linux NFS client appends XDR padding to all odd-sized Read chunks.
This shouldn't be a problem because:

 - RFC 8166-compliant servers are supposed to work with or without
   that XDR padding in Read chunks.

 - Since the padding is now in the same memory region as the data
   payload, a separate memory registration is not needed. In
   addition, the link layer extends data in RDMA Read responses to
   4-byte boundaries anyway. Thus there is now no savings when the
   padding is not included.

Because older kernels include the payload's XDR padding in the
tail kvec, a fix there will be more complicated. Thus backporting
this patch is not recommended.

Reported by: Olga Kornievskaia <Olga.Kornievskaia@netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-02-05 11:16:56 -05:00
Chuck Lever
84dff5eb86 rpcrdma: Fix comments about reverse-direction operation
During the final stages of publication of RFC 8167, reviewers
requested that we use the term "reverse direction" rather than
"backwards direction". Update comments to reflect this preference.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-02-05 11:16:56 -05:00
Chuck Lever
67b16625d1 xprtrdma: Refactor invocations of offset_in_page()
Clean up so that offset_in_page() is invoked less often in the
most common case, which is mapping xdr->pages.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-02-05 11:16:56 -05:00
Chuck Lever
54e6aec57c xprtrdma: Simplify rpcrdma_convert_kvec() and frwr_map()
Clean up.

Remove a conditional branch from the SGL set-up loop in frwr_map():
Instead of using either sg_set_page() or sg_set_buf(), initialize
the mr_page field properly when rpcrdma_convert_kvec() converts the
kvec to an SGL entry. frwr_map() can then invoke sg_set_page()
unconditionally.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-02-05 11:16:55 -05:00
Chuck Lever
9929f4adce xprtrdma: Remove FMR support in rpcrdma_convert_iovs()
Support for FMR was removed by commit ba69cd122e ("xprtrdma:
Remove support for FMR memory registration") [Dec 2018]. That means
the buffer-splitting behavior of rpcrdma_convert_kvec(), added by
commit 821c791a0b ("xprtrdma: Segment head and tail XDR buffers
on page boundaries") [Mar 2016], is no longer necessary. FRWR
memory registration handles this case with aplomb.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2021-02-05 11:16:55 -05:00
Chuck Lever
dd2d055b27 svcrdma: DMA-sync the receive buffer in svc_rdma_recvfrom()
The Receive completion handler doesn't look at the contents of the
Receive buffer. The DMA sync isn't terribly expensive but it's one
less thing that needs to be done by the Receive completion handler,
which is single-threaded (per svc_xprt). This helps scalability.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-01-25 09:36:28 -05:00
Chuck Lever
43042b90ca svcrdma: Reduce Receive doorbell rate
This is similar to commit e340c2d6ef ("xprtrdma: Reduce the
doorbell rate (Receive)") which added Receive batching to the
client.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25 09:36:28 -05:00
Chuck Lever
c6226ff9a6 svcrdma: Deprecate stat variables that are no longer used
Clean up. We are not permitted to remove old proc files. Instead,
convert these variables to stubs that are only ever allowed to
display a value of zero.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25 09:36:28 -05:00
Chuck Lever
1e7e557316 svcrdma: Restore read and write stats
Now that we have an efficient mechanism to update these two stats,
let's start maintaining them again.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25 09:36:28 -05:00
Chuck Lever
22df5a2246 svcrdma: Convert rdma_stat_sq_starve to a per-CPU counter
Avoid the overhead of a memory bus lock cycle for counting a value
that is hardly every used.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25 09:36:28 -05:00
Chuck Lever
df971cd853 svcrdma: Convert rdma_stat_recv to a per-CPU counter
Receives are frequent events. Avoid the overhead of a memory bus
lock cycle for counting a value that is hardly every used.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25 09:36:28 -05:00
Chuck Lever
59a00257c6 svcrdma: Refactor svc_rdma_init() and svc_rdma_clean_up()
Setting up the proc variables is about to get more complicated.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25 09:36:28 -05:00
Linus Torvalds
74f602dc96 NFS client updates for Linux 5.11
Highlights include:
 
 Features:
 - NFSv3: Add emulation of lookupp() to improve open_by_filehandle()
   support.
 - A series of patches to improve readdir performance, particularly with
   large directories.
 - Basic support for using NFS/RDMA with the pNFS files and flexfiles
   drivers.
 - Micro-optimisations for RDMA.
 - RDMA tracing improvements.
 
 Bugfixes:
 - Fix a long standing bug with xs_read_xdr_buf() when receiving partial
   pages (Dan Aloni).
 - Various fixes for getxattr and listxattr, when used over non-TCP
   transports.
 - Fixes for containerised NFS from Sargun Dhillon.
 - switch nfsiod to be an UNBOUND workqueue (Neil Brown).
 - READDIR should not ask for security label information if there is no
   LSM policy. (Olga Kornievskaia)
 - Avoid using interval-based rebinding with TCP in lockd (Calum Mackay).
 - A series of RPC and NFS layer fixes to support the NFSv4.2 READ_PLUS code.
 - A couple of fixes for pnfs/flexfiles read failover
 
 Cleanups:
 - Various cleanups for the SUNRPC xdr code in conjunction with the
   READ_PLUS fixes.
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Merge tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Features:

   - NFSv3: Add emulation of lookupp() to improve open_by_filehandle()
     support

   - A series of patches to improve readdir performance, particularly
     with large directories

   - Basic support for using NFS/RDMA with the pNFS files and flexfiles
     drivers

   - Micro-optimisations for RDMA

   - RDMA tracing improvements

  Bugfixes:

   - Fix a long standing bug with xs_read_xdr_buf() when receiving
     partial pages (Dan Aloni)

   - Various fixes for getxattr and listxattr, when used over non-TCP
     transports

   - Fixes for containerised NFS from Sargun Dhillon

   - switch nfsiod to be an UNBOUND workqueue (Neil Brown)

   - READDIR should not ask for security label information if there is
     no LSM policy (Olga Kornievskaia)

   - Avoid using interval-based rebinding with TCP in lockd (Calum
     Mackay)

   - A series of RPC and NFS layer fixes to support the NFSv4.2
     READ_PLUS code

   - A couple of fixes for pnfs/flexfiles read failover

  Cleanups:

   - Various cleanups for the SUNRPC xdr code in conjunction with the
     READ_PLUS fixes"

* tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (90 commits)
  NFS/pNFS: Fix a typo in ff_layout_resend_pnfs_read()
  pNFS/flexfiles: Avoid spurious layout returns in ff_layout_choose_ds_for_read
  NFSv4/pnfs: Add tracing for the deviceid cache
  fs/lockd: convert comma to semicolon
  NFSv4.2: fix error return on memory allocation failure
  NFSv4.2/pnfs: Don't use READ_PLUS with pNFS yet
  NFSv4.2: Deal with potential READ_PLUS data extent buffer overflow
  NFSv4.2: Don't error when exiting early on a READ_PLUS buffer overflow
  NFSv4.2: Handle hole lengths that exceed the READ_PLUS read buffer
  NFSv4.2: decode_read_plus_hole() needs to check the extent offset
  NFSv4.2: decode_read_plus_data() must skip padding after data segment
  NFSv4.2: Ensure we always reset the result->count in decode_read_plus()
  SUNRPC: When expanding the buffer, we may need grow the sparse pages
  SUNRPC: Cleanup - constify a number of xdr_buf helpers
  SUNRPC: Clean up open coded setting of the xdr_stream 'nwords' field
  SUNRPC: _copy_to/from_pages() now check for zero length
  SUNRPC: Cleanup xdr_shrink_bufhead()
  SUNRPC: Fix xdr_expand_hole()
  SUNRPC: Fixes for xdr_align_data()
  SUNRPC: _shift_data_left/right_pages should check the shift length
  ...
2020-12-17 12:15:03 -08:00
Trond Myklebust
edffb84cc8 NFSoRDmA Client updates for Linux 5.11
Cleanups and improvements:
   - Remove use of raw kernel memory addresses in tracepoints
   - Replace dprintk() call sites in ERR_CHUNK path
   - Trace unmap sync calls
   - Optimize MR DMA-unmapping
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Merge tag 'nfs-rdma-for-5.11-1' of git://git.linux-nfs.org/projects/anna/linux-nfs into linux-next

NFSoRDmA Client updates for Linux 5.11

Cleanups and improvements:
  - Remove use of raw kernel memory addresses in tracepoints
  - Replace dprintk() call sites in ERR_CHUNK path
  - Trace unmap sync calls
  - Optimize MR DMA-unmapping

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-15 20:08:41 -05:00
Chuck Lever
15261b9126 xprtrdma: Fix XDRBUF_SPARSE_PAGES support
Olga K. observed that rpcrdma_marsh_req() allocates sparse pages
only when it has determined that a Reply chunk is necessary. There
are plenty of cases where no Reply chunk is needed, but the
XDRBUF_SPARSE_PAGES flag is set. The result would be a crash in
rpcrdma_inline_fixup() when it tries to copy parts of the received
Reply into a missing page.

To avoid crashing, handle sparse page allocation up front.

Until XATTR support was added, this issue did not appear often
because the only SPARSE_PAGES consumer always expected a reply large
enough to always require a Reply chunk.

Reported-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:07 -05:00
Trond Myklebust
d5aa6b22e2 SUNRPC: xprt_load_transport() needs to support the netid "rdma6"
According to RFC5666, the correct netid for an IPv6 addressed RDMA
transport is "rdma6", which we've supported as a mount option since
Linux-4.7. The problem is when we try to load the module "xprtrdma6",
that will fail, since there is no modulealias of that name.

Fixes: 181342c5eb ("xprtrdma: Add rdma6 option to support NFS/RDMA IPv6")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-02 14:05:52 -05:00
Chuck Lever
d7cc739726 svcrdma: support multiple Read chunks per RPC
An efficient way to handle multiple Read chunks is to post them all
together and then take a single completion. This is also how the
code is already structured: when the Read completion fires, all
portions of the incoming RPC message are available to be assembled.

The difficult problem is setting up the Read sink buffers so that
the server pulls the client's data into place, making subsequent
pull-up unnecessary. There are several cases:

* No Read chunks. No-op.

* One data item Read chunk. This is the fast case, where the inline
  part of the RPC-over-RDMA message becomes the head and tail, and
  the data item chunk is placed in buf->pages.

* A Position-zero Read chunk. Treated like TCP: the Read chunk is
  pulled into contiguous pages.

+ A Position-zero Read chunk with data item chunks. Treated like
  TCP: all of the Read chunks are pulled into contiguous pages.

+ Multiple data item chunks. Treated like TCP: the inline part is
  copied and the data item chunks are pulled into contiguous pages.

The "*" cases are already supported. This patch adds support for the
"+" cases.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:23 -05:00
Chuck Lever
d96962e6d0 svcrdma: Use the new parsed chunk list when pulling Read chunks
As a pre-requisite for handling multiple Read chunks in each Read
list, convert svc_rdma_recv_read_chunk() to use the new parsed Read
chunk list.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:23 -05:00
Chuck Lever
bafe9c27d5 svcrdma: Rename info::ri_chunklen
I'm about to change the purpose of ri_chunklen: Instead of tracking
the number of bytes in one Read chunk, it will track the total
number of bytes in the Read list. Rename it for clarity.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:23 -05:00
Chuck Lever
b704be09dc svcrdma: Clean up chunk tracepoints
We already have trace_svcrdma_decode_rseg(), which records each
ingress Read segment. Instead of reporting those again when they
are about to be posted as RDMA Reads, let's fire one tracepoint
before posting each type of chunk.

So we'll get:

        nfsd-1998  [002]   321.666615: svcrdma_decode_rseg:  cq.id=4 cid=42 segno=0 position=0 192@0x013ca9ebfae14000:0xb0010b05
        nfsd-1998  [002]   321.666615: svcrdma_decode_rseg:  cq.id=4 cid=42 segno=1 position=0 7688@0x013ca9ebf914e000:0xb0010a05
        nfsd-1998  [002]   321.666615: svcrdma_decode_rseg:  cq.id=4 cid=42 segno=2 position=0 28@0x013ca9ebfae15000:0xb0010905
        nfsd-1998  [002]   321.666622: svcrdma_decode_rqst:  cq.id=4 cid=42 xid=0x013ca9eb vers=1 credits=128 proc=RDMA_NOMSG hdrlen=100

        nfsd-1998  [002]   321.666642: svcrdma_post_read_chunk: cq.id=3 cid=112 sqecount=3

kworker/2:1H-221   [002]   321.673949: svcrdma_wc_read:      cq.id=3 cid=112 status=SUCCESS (0/0x0)

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:23 -05:00
Chuck Lever
7954c8503b svcrdma: Remove chunk list pointers
Clean up: These pointers are no longer used.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:23 -05:00
Chuck Lever
41bc163ffe svcrdma: Support multiple Write chunks in svc_rdma_send_reply_chunk
Refactor svc_rdma_send_reply_chunk() so that it Sends only the parts
of rq_res that do not contain a result payload.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:23 -05:00
Chuck Lever
2371bcc056 svcrdma: Support multiple Write chunks in svc_rdma_map_reply_msg()
Refactor: svc_rdma_map_reply_msg() is restructured to DMA map only
the parts of rq_res that do not contain a result payload.

This change has been tested to confirm that it does not cause a
regression in the no Write chunk and single Write chunk cases.
Multiple Write chunks have not been tested.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:23 -05:00
Chuck Lever
9d0b09d5ef svcrdma: Support multiple write chunks when pulling up
When counting the number of SGEs needed to construct a Send request,
do not count result payloads. And, when copying the Reply message
into the pull-up buffer, result payloads are not to be copied to the
Send buffer.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
6911f3e10c svcrdma: Use parsed chunk lists to encode Reply transport headers
Refactor: Instead of re-parsing the ingress RPC Call transport
header when constructing the egress RPC Reply transport header, use
the new parsed Write list and Reply chunk, which are version-
agnostic and already XDR decoded.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
7a1cbfa180 svcrdma: Use parsed chunk lists to construct RDMA Writes
Refactor: Instead of re-parsing the ingress RPC Call transport
header when constructing RDMA Writes, use the new parsed chunk lists
for the Write list and Reply chunk, which are version-agnostic and
already XDR-decoded.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
58b2e0fefa svcrdma: Use parsed chunk lists to detect reverse direction replies
Refactor: Don't duplicate header decoding smarts here. Instead, use
the new parsed chunk lists.

Note that the XID sanity test is also removed. The XID is already
looked up by the cb handler, and is rejected if it's not recognized.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
eb3de6a49d svcrdma: Use parsed chunk lists to derive the inv_rkey
Refactor: Don't duplicate header decoding smarts here. Instead, use
the new parsed chunk lists.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
78147ca8b4 svcrdma: Add a "parsed chunk list" data structure
This simple data structure binds the location of each data payload
inside of an RPC message to the chunk that will be used to push it
to or pull it from the client.

There are several benefits to this small additional overhead:

 * It enables support for more than one chunk in incoming Read and
   Write lists.

 * It translates the version-specific on-the-wire format into a
   generic in-memory structure, enabling support for multiple
   versions of the RPC/RDMA transport protocol.

 * It enables the server to re-organize a chunk list if it needs to
   adjust where Read chunk data lands in server memory without
   altering the contents of the XDR-encoded Receive buffer.

Construction of these lists is done while sanity checking each
incoming RPC/RDMA header. Subsequent patches will make use of the
generated data structures.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
ded380f100 svcrdma: Clean up svc_rdma_encode_reply_chunk()
Refactor: Match the control flow of svc_rdma_encode_write_list().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
f6ad77590a svcrdma: Post RDMA Writes while XDR encoding replies
The only RPC/RDMA ordering requirement between RDMA Writes and RDMA
Sends is that the responder must post the Writes on the Send queue
before posting the Send that conveys the RPC Reply for that Write
payload.

The Linux NFS server implementation now has a transport method that
can post result Payload Writes earlier than svc_rdma_sendto:

   ->xpo_result_payload()

This gets RDMA Writes going earlier so they are more likely to be
complete at the remote end before the Send completes.

Some care must be taken with pulled-up Replies. We don't want to
push the Write chunk and then send the same payload data via Send.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
76e5492b16 NFSD: Invoke svc_encode_result_payload() in "read" NFSD encoders
Have the NFSD encoders annotate the boundaries of every
direct-data-placement eligible result data payload. Then change
svcrdma to use that annotation instead of the xdr->page_len
when handling Write chunks.

For NFSv4 on RDMA, that enables the ability to recognize multiple
result payloads per compound. This is a pre-requisite for supporting
multiple Write chunks per RPC transaction.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:22 -05:00
Chuck Lever
03493bca08 SUNRPC: Rename svc_encode_read_payload()
Clean up: "result payload" is a less confusing name for these
payloads. "READ payload" reflects only the NFS usage.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:21 -05:00
Chuck Lever
ab1394ee7a svcrdma: Refactor the RDMA Write path
Refactor for subsequent changes.

Constify the xdr_buf argument to ensure the code here does not
modify it, and to enable callers to pass in a
"const struct xdr_buf *".

At the same time, rename the helper functions, which emit RDMA
Writes, not RDMA Sends, and add documenting comments.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:21 -05:00
Chuck Lever
51bad8cc13 svcrdma: Const-ify the xdr_buf arguments
Clean up: Ensure the code in rw.c does not modify the argument, and
enable callers to also use "const struct xdr_buf *".

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:21 -05:00
Chuck Lever
e5decb2eb5 svcrdma: Catch another Reply chunk overflow case
When space in the Reply chunk runs out in the middle of a segment,
we end up passing a zero-length SGL to rdma_rw_ctx_init(), and it
oopses.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30 13:00:21 -05:00
Chuck Lever
7a03aeb66c xprtrdma: Micro-optimize MR DMA-unmapping
Now that rpcrdma_ep is no longer part of rpcrdma_xprt, there are
four or five serial address dereferences needed to get to the
IB device needed for DMA unmapping.

Instead, let's use the same pattern that regbufs use: cache a
pointer to the device in the MR, and use that as the indication
that unmapping is necessary.

This also guarantees that the exact same device is used for DMA
mapping and unmapping, even if the r_xprt's ep has been replaced. I
don't think this can happen today, but future changes might break
this assumption.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:57:39 -05:00
Chuck Lever
ef2be5918f xprtrdma: Move rpcrdma_mr_put()
Clean up: This function is now invoked only in frwr_ops.c. The move
enables deduplication of the trace_xprtrdma_mr_unmap() call site.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:52:18 -05:00
Chuck Lever
8e24e191d4 xprtrdma: Trace unmap_sync calls
->buf_free is called nearly once per RPC. Only rarely does
xprt_rdma_free() have to do anything, thus tracing every one of
these calls seems unnecessary. Instead, just throw a trace event
when that one occasional RPC still has MRs that need to be
released.

xprt_rdma_free() is further micro-optimized to reduce the amount of
work done in the common case.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:49:12 -05:00
Chuck Lever
7703db978d xprtrdma: Display the task ID when reporting MR events
Tie each MR event to the requesting rpc_task to make it easier to
follow MR ownership and control flow.

MR unmapping and recycling can happen in the background, after an
MR's mr_req field is stale, so set up a separate tracepoint class
for those events.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:46:54 -05:00
Chuck Lever
0307cdec7c xprtrdma: Clean up trace_xprtrdma_nomrs()
- Rename it following the "_err" suffix convention
- Replace display of kernel memory addresses
- Tie MR exhaustion to a peer IP address, similar to the createmrs
   tracepoint

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:44:05 -05:00
Chuck Lever
d11e934606 xprtrdma: Clean up xprtrdma callback tracepoints
- Replace displayed kernel memory addresses
- Tie the XID and event with the peer's IP address

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:40:38 -05:00
Chuck Lever
03ffd92494 xprtrdma: Clean up tracepoints in the reply path
Replace unnecessary display of kernel memory addresses.

Also, there are no longer any trace_xprtrdma_defer_cmp() call sites.
And remove the trace_xprtrdma_leaked_rep() tracepoint because there
doesn't seem to be an overwhelming need to have a tracepoint for
catching a software bug that has long since been fixed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:36:00 -05:00
Chuck Lever
3a9568fedc xprtrdma: Clean up reply parsing error tracepoints
- Rename the tracepoints with the "_err" suffix to indicate these
  are rare error events
- Replace display of kernel memory addresses
- Tie the XID and error to a connection IP address instead

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:32:31 -05:00
Chuck Lever
36a55edfc3 xprtrdma: Clean up trace_xprtrdma_post_linv
- Replace the display of kernel memory addresses
- Add "_err" to the end of its name to indicate that it's a
  tracepoint that fires only when there's an error

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:26:06 -05:00
Chuck Lever
5ecef9c843 xprtrdma: Introduce FRWR completion IDs
Set up a completion ID in each rpcrdma_frwr. The ID is used to match
an incoming completion to a transport (CQ) and other MR-related
activity.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:23:29 -05:00
Chuck Lever
b2e7467f26 xprtrdma: Introduce Send completion IDs
Set up a completion ID in each rpcrdma_req. The ID is used to match
an incoming Send completion to a transport and to a previous
ib_post_send().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:21:12 -05:00
Chuck Lever
af5865d278 xprtrdma: Introduce Receive completion IDs
Set up a completion ID in each rpcrdma_rep. The ID is used to match
an incoming Receive completion to a transport and to a previous
ib_post_recv().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:18:58 -05:00
Chuck Lever
3821e232eb xprtrdma: Replace dprintk call sites in ERR_CHUNK path
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11 10:12:30 -05:00
Linus Torvalds
24717cfbbb The one new feature this time, from Anna Schumaker, is READ_PLUS, which
has the same arguments as READ but allows the server to return an array
 of data and hole extents.
 
 Otherwise it's a lot of cleanup and bugfixes.
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Merge tag 'nfsd-5.10' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "The one new feature this time, from Anna Schumaker, is READ_PLUS,
  which has the same arguments as READ but allows the server to return
  an array of data and hole extents.

  Otherwise it's a lot of cleanup and bugfixes"

* tag 'nfsd-5.10' of git://linux-nfs.org/~bfields/linux: (43 commits)
  NFSv4.2: Fix NFS4ERR_STALE error when doing inter server copy
  SUNRPC: fix copying of multiple pages in gss_read_proxy_verf()
  sunrpc: raise kernel RPC channel buffer size
  svcrdma: fix bounce buffers for unaligned offsets and multiple pages
  nfsd: remove unneeded break
  net/sunrpc: Fix return value for sysctl sunrpc.transports
  NFSD: Encode a full READ_PLUS reply
  NFSD: Return both a hole and a data segment
  NFSD: Add READ_PLUS hole segment encoding
  NFSD: Add READ_PLUS data support
  NFSD: Hoist status code encoding into XDR encoder functions
  NFSD: Map nfserr_wrongsec outside of nfsd_dispatch
  NFSD: Remove the RETURN_STATUS() macro
  NFSD: Call NFSv2 encoders on error returns
  NFSD: Fix .pc_release method for NFSv2
  NFSD: Remove vestigial typedefs
  NFSD: Refactor nfsd_dispatch() error paths
  NFSD: Clean up nfsd_dispatch() variables
  NFSD: Clean up stale comments in nfsd_dispatch()
  NFSD: Clean up switch statement in nfsd_dispatch()
  ...
2020-10-22 09:44:27 -07:00
Dan Aloni
c327a310ec svcrdma: fix bounce buffers for unaligned offsets and multiple pages
This was discovered using O_DIRECT at the client side, with small
unaligned file offsets or IOs that span multiple file pages.

Fixes: e248aa7be8 ("svcrdma: Remove max_sge check at connect time")
Signed-off-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-16 15:15:04 -04:00
Randy Dunlap
1cc5213baa net: sunrpc: delete repeated words
Drop duplicate words in net/sunrpc/.
Also fix "Anyone" to be "Any one".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-09-25 18:01:26 -04:00
Julia Lawall
ed38c33f1c xprtrdma: drop double zeroing
sg_init_table zeroes its first argument, so the allocation of that argument
doesn't have to.

the semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,n,flags;
@@

x =
- kcalloc
+ kmalloc_array
  (n,sizeof(*x),flags)
...
sg_init_table(x,n)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-21 12:15:25 -04:00
Chuck Lever
ac1ae53421 SUNRPC: Hoist trace_xprtrdma_op_setport into generic code
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-21 10:21:09 -04:00
Chuck Lever
7806948753 SUNRPC: Remove debugging instrumentation from xprt_release
These instruments don't appear to add any substantial value.

We already have this at the termination of each RPC:

          iozone-2617  [002]   975.713126: rpc_stats_latency:    task:418@5 xid=0x260eab5d nfsv3 LOOKUP backlog=15 rtt=32 execute=58
          iozone-2617  [002]   975.713127: xprt_release_cong:    task:418@5 snd_task:4294967295 cong=256 cwnd=16384
          iozone-2617  [002]   975.713127: xprt_put_cong:        task:418@5 snd_task:4294967295 cong=0 cwnd=16384

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-21 10:21:08 -04:00
Chuck Lever
06e234c613 SUNRPC: Hoist trace_xprtrdma_op_allocate into generic code
Introduce a tracepoint in call_allocate that reports the exact
sizes in the RPC buffer allocation request and the status of the
result. This helps catch problems with XDR buffer provisioning,
and replaces transport-specific debugging instrumentation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-21 10:21:08 -04:00
Linus Torvalds
ab29a807a7 NFS client bugfixes for Linux 5.9
Highlights include:
 
 Bugfixes:
 - Fix an NFS/RDMA resource leak
 - Fix the error handling during delegation recall
 - NFSv4.0 needs to return the delegation on a zero-stateid SETATTR
 - Stop printk reading past end of string
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Merge tag 'nfs-for-5.9-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:

 - Fix an NFS/RDMA resource leak

 - Fix the error handling during delegation recall

 - NFSv4.0 needs to return the delegation on a zero-stateid SETATTR

 - Stop printk reading past end of string

* tag 'nfs-for-5.9-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: stop printk reading past end of string
  NFS: Zero-stateid SETATTR should first return delegation
  NFSv4.1 handle ERR_DELAY error reclaiming locking state on delegation recall
  xprtrdma: Release in-flight MRs on disconnect
2020-09-09 11:14:20 -07:00
Chuck Lever
5de55ce951 xprtrdma: Release in-flight MRs on disconnect
Dan Aloni reports that when a server disconnects abruptly, a few
memory regions are left DMA mapped. Over time this leak could pin
enough I/O resources to slow or even deadlock an NFS/RDMA client.

I found that if a transport disconnects before pending Send and
FastReg WRs can be posted, the to-be-registered MRs are stranded on
the req's rl_registered list and never released -- since they
weren't posted, there's no Send completion to DMA unmap them.

Reported-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-08-26 15:29:21 -04:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds
7a6b60441f Highlights:
- Support for user extended attributes on NFS (RFC 8276)
 - Further reduce unnecessary NFSv4 delegation recalls
 
 Notable fixes:
 
 - Fix recent krb5p regression
 - Address a few resource leaks and a rare NULL dereference
 
 Other:
 
 - De-duplicate RPC/RDMA error handling and other utility functions
 - Replace storage and display of kernel memory addresses by tracepoints
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Merge tag 'nfsd-5.9' of git://git.linux-nfs.org/projects/cel/cel-2.6

Pull NFS server updates from Chuck Lever:
 "Highlights:
   - Support for user extended attributes on NFS (RFC 8276)
   - Further reduce unnecessary NFSv4 delegation recalls

  Notable fixes:
   - Fix recent krb5p regression
   - Address a few resource leaks and a rare NULL dereference

  Other:
   - De-duplicate RPC/RDMA error handling and other utility functions
   - Replace storage and display of kernel memory addresses by tracepoints"

* tag 'nfsd-5.9' of git://git.linux-nfs.org/projects/cel/cel-2.6: (38 commits)
  svcrdma: CM event handler clean up
  svcrdma: Remove transport reference counting
  svcrdma: Fix another Receive buffer leak
  SUNRPC: Refresh the show_rqstp_flags() macro
  nfsd: netns.h: delete a duplicated word
  SUNRPC: Fix ("SUNRPC: Add "@len" parameter to gss_unwrap()")
  nfsd: avoid a NULL dereference in __cld_pipe_upcall()
  nfsd4: a client's own opens needn't prevent delegations
  nfsd: Use seq_putc() in two functions
  svcrdma: Display chunk completion ID when posting a rw_ctxt
  svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send()
  svcrdma: Introduce Send completion IDs
  svcrdma: Record Receive completion ID in svc_rdma_decode_rqst
  svcrdma: Introduce Receive completion IDs
  svcrdma: Introduce infrastructure to support completion IDs
  svcrdma: Add common XDR encoders for RDMA and Read segments
  svcrdma: Add common XDR decoders for RDMA and Read segments
  SUNRPC: Add helpers for decoding list discriminators symbolically
  svcrdma: Remove declarations for functions long removed
  svcrdma: Clean up trace_svcrdma_send_failed() tracepoint
  ...
2020-08-09 13:58:04 -07:00
Chuck Lever
b297fed699 svcrdma: CM event handler clean up
Now that there's a core tracepoint that reports these events, there's
no need to maintain dprintk() call sites in each arm of the switch
statements.

We also refresh the documenting comments.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-28 10:18:15 -04:00
Chuck Lever
365e9992b9 svcrdma: Remove transport reference counting
Jason tells me that a ULP cannot rely on getting an ESTABLISHED
and DISCONNECTED event pair for each connection, so transport
reference counting in the CM event handler will never be reliable.

Now that we have ib_drain_qp(), svcrdma should no longer need to
hold transport references while Sends and Receives are posted. So
remove the get/put call sites in the CM event handlers.

This eliminates a significant source of locked memory bus traffic.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-28 10:18:14 -04:00
Chuck Lever
64d2642251 svcrdma: Fix another Receive buffer leak
During a connection tear down, the Receive queue is flushed before
the device resources are freed. Typically, all the Receives flush
with IB_WR_FLUSH_ERR.

However, any pending successful Receives flush with IB_WR_SUCCESS,
and the server automatically posts a fresh Receive to replace the
completing one. This happens even after the connection has closed
and the RQ is drained. Receives that are posted after the RQ is
drained appear never to complete, causing a Receive resource leak.
The leaked Receive buffer is left DMA-mapped.

To prevent these late-posted recv_ctxt's from leaking, block new
Receive posting after XPT_CLOSE is set.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-28 10:18:13 -04:00
Colin Ian King
912288442c xprtrdma: fix incorrect header size calculations
Currently the header size calculations are using an assignment
operator instead of a += operator when accumulating the header
size leading to incorrect sizes.  Fix this by using the correct
operator.

Addresses-Coverity: ("Unused value")
Fixes: 302d3deb20 ("xprtrdma: Prevent inline overflow")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-07-15 13:01:01 -04:00
Chuck Lever
6787f0bea2 svcrdma: Display chunk completion ID when posting a rw_ctxt
Re-use the post_rw tracepoint (safely) to trace cc_info lifetime
events, including completion IDs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13 17:28:24 -04:00
Chuck Lever
17f70f8dd5 svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send()
First, refactor: Dereference the svc_rdma_send_ctxt inside
svc_rdma_send() instead of at every call site.

Then, it can be passed into trace_svcrdma_post_send() to get the
proper completion ID.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13 17:28:24 -04:00
Chuck Lever
3ac56c2fb1 svcrdma: Introduce Send completion IDs
Set up a completion ID in each svc_rdma_send_ctxt. The ID is used
to match an incoming Send completion to a transport and to a
previous ib_post_send().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13 17:28:24 -04:00