Commit Graph

152 Commits

Author SHA1 Message Date
Chuck Lever 4201c74647 svcrdma: Introduce svc_rdma_send_ctxt
svc_rdma_op_ctxt's are pre-allocated and maintained on a per-xprt
free list. This eliminates the overhead of calling kmalloc / kfree,
both of which grab a globally shared lock that disables interrupts.
Introduce a replacement to svc_rdma_op_ctxt's that is built
especially for the svcrdma Send path.

Subsequent patches will take advantage of this new structure by
allocating real resources which are then cached in these objects.
The allocations are freed when the transport is torn down.

I've renamed the structure so that static type checking can be used
to ensure that uses of op_ctxt and send_ctxt are not confused. As an
additional clean up, structure fields are renamed to conform with
kernel coding conventions.

Additional clean ups:
- Handle svc_rdma_send_ctxt_get allocation failure at each call
  site, rather than pre-allocating and hoping we guessed correctly
- All send_ctxt_put call-sites request page freeing, so remove
  the @free_pages argument
- All send_ctxt_put call-sites unmap SGEs, so fold that into
  svc_rdma_send_ctxt_put

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11 15:48:57 -04:00
Chuck Lever 3316f06311 svcrdma: Persistently allocate and DMA-map Receive buffers
The current Receive path uses an array of pages which are allocated
and DMA mapped when each Receive WR is posted, and then handed off
to the upper layer in rqstp::rq_arg. The page flip releases unused
pages in the rq_pages pagelist. This mechanism introduces a
significant amount of overhead.

So instead, kmalloc the Receive buffer, and leave it DMA-mapped
while the transport remains connected. This confers a number of
benefits:

* Each Receive WR requires only one receive SGE, no matter how large
  the inline threshold is. This helps the server-side NFS/RDMA
  transport operate on less capable RDMA devices.

* The Receive buffer is left allocated and mapped all the time. This
  relieves svc_rdma_post_recv from the overhead of allocating and
  DMA-mapping a fresh buffer.

* svc_rdma_wc_receive no longer has to DMA unmap the Receive buffer.
  It has to DMA sync only the number of bytes that were received.

* svc_rdma_build_arg_xdr no longer has to free a page in rq_pages
  for each page in the Receive buffer, making it a constant-time
  function.

* The Receive buffer is now plugged directly into the rq_arg's
  head[0].iov_vec, and can be larger than a page without spilling
  over into rq_arg's page list. This enables simplification of
  the RDMA Read path in subsequent patches.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11 15:48:57 -04:00
Chuck Lever 2c577bfea8 svcrdma: Remove sc_rq_depth
Clean up: No need to retain rq_depth in struct svcrdma_xprt, it is
used only in svc_rdma_accept().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11 15:48:57 -04:00
Chuck Lever ecf85b2384 svcrdma: Introduce svc_rdma_recv_ctxt
svc_rdma_op_ctxt's are pre-allocated and maintained on a per-xprt
free list. This eliminates the overhead of calling kmalloc / kfree,
both of which grab a globally shared lock that disables interrupts.
To reduce contention further, separate the use of these objects in
the Receive and Send paths in svcrdma.

Subsequent patches will take advantage of this separation by
allocating real resources which are then cached in these objects.
The allocations are freed when the transport is torn down.

I've renamed the structure so that static type checking can be used
to ensure that uses of op_ctxt and recv_ctxt are not confused. As an
additional clean up, structure fields are renamed to conform with
kernel coding conventions.

As a final clean up, helpers related to recv_ctxt are moved closer
to the functions that use them.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11 15:48:57 -04:00
Chuck Lever bd2abef333 svcrdma: Trace key RDMA API events
This includes:
  * Posting on the Send and Receive queues
  * Send, Receive, Read, and Write completion
  * Connect upcalls
  * QP errors

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11 15:48:57 -04:00
Chuck Lever 98895edbe3 svcrdma: Trace key RPC/RDMA protocol events
This includes:
  * Transport accept and tear-down
  * Decisions about using Write and Reply chunks
  * Each RDMA segment that is handled
  * Whenever an RDMA_ERR is sent

As a clean-up, I've standardized the order of the includes, and
removed some now redundant dprintk call sites.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11 15:48:57 -04:00
Chuck Lever 8dafcbee41 svcrdma: Use passed-in net namespace when creating RDMA listener
Ensure each RDMA listener and its children transports are created in
the same net namespace as the user that started the NFS service.
This is similar to how listener sockets are created in
svc_create_socket, required for enabling support for containers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11 15:48:57 -04:00
Chuck Lever bcf3ffd405 svcrdma: Add proper SPDX tags for NetApp-contributed source
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11 15:48:57 -04:00
Chuck Lever ece200ddd5 sunrpc: Save remote presentation address in svc_xprt for trace events
TP_printk defines a format string that is passed to user space for
converting raw trace event records to something human-readable.

My user space's printf (Oracle Linux 7), however, does not have a
%pI format specifier. The result is that what is supposed to be an
IP address in the output of "trace-cmd report" is just a string that
says the field couldn't be displayed.

To fix this, adopt the same approach as the client: maintain a pre-
formated presentation address for occasions when %pI is not
available.

The location of the trace_svc_send trace point is adjusted so that
rqst->rq_xprt is not NULL when the trace event is recorded.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-04-03 15:08:11 -04:00
Chuck Lever 989f881ebf svc: Simplify ->xpo_secure_port
Clean up: Instead of returning a value that is used to set or clear
a bit, just make ->xpo_secure_port mangle that bit, and return void.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-04-03 15:08:09 -04:00
Chuck Lever 97cc326450 svcrdma: Consult max_qp_init_rd_atom when accepting connections
The target needs to return the lesser of the client's Inbound RDMA
Read Queue Depth (IRD), provided in the connection parameters, and
the local device's Outbound RDMA Read Queue Depth (ORD). The latter
limit is max_qp_init_rd_atom, not max_qp_rd_atom.

The svcrdma_ord value caps the ORD value for iWARP transports, which
do not exchange ORD/IRD values at connection time. Since no other
Linux kernel RDMA-enabled storage target sees fit to provide this
cap, I'm removing it here too.

initiator_depth is a u8, so ensure the computed ORD value does not
overflow that field.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-03-20 17:32:13 -04:00
Chuck Lever 0c4398ff8b svcrdma: Use pr_err to report Receive errors
Clean up: Other completion handlers use pr_err, not pr_warn.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-03-20 17:32:12 -04:00
Chuck Lever 482725027f svcrdma: Post Receives in the Receive completion handler
This change improves Receive efficiency by posting Receives only
on the same CPU that handles Receive completion. Improved latency
and throughput has been noted with this change.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-01-18 11:52:51 -05:00
Chuck Lever 77a08867a6 svcrdma: Enqueue after setting XPT_CLOSE in completion handlers
I noticed the server was sometimes not closing the connection after
a flushed Send. For example, if the client responds with an RNR NAK
to a Reply from the server, that client might be deadlocked, and
thus wouldn't send any more traffic. Thus the server wouldn't have
any opportunity to notice the XPT_CLOSE bit has been set.

Enqueue the transport so that svcxprt notices the bit even if there
is no more transport activity after a flushed completion, QP access
error, or device removal event.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-By: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-11-07 16:44:02 -05:00
Chuck Lever 26fb2254dd svcrdma: Estimate Send Queue depth properly
The rdma_rw API adjusts max_send_wr upwards during the
rdma_create_qp() call. If the ULP actually wants to take advantage
of these extra resources, it must increase the size of its send
completion queue (created before rdma_create_qp is called) and
increase its send queue accounting limit.

Use the new rdma_rw_mr_factor API to figure out the correct value
to use for the Send Queue and Send Completion Queue depths.

And, ensure that the chosen Send Queue depth for a newly created
transport does not overrun the QP WR limit of the underlying device.

Lastly, there's no longer a need to carry the Send Queue depth in
struct svcxprt_rdma, since the value is used only in the
svc_rdma_accept() path.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-09-05 15:15:31 -04:00
Chuck Lever 5a25bfd28c svcrdma: Limit RQ depth
Ensure that the chosen Receive Queue depth for a newly created
transport does not overrun the QP WR limit of the underlying device.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-09-05 15:15:30 -04:00
Chuck Lever 2412e92760 sunrpc: Const-ify instances of struct svc_xprt_ops
Close an attack vector by moving the arrays of server-side transport
methods to read-only memory.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-08-24 22:13:50 -04:00
Chuck Lever 9450ca8e2f svcrdma: Clean up after converting svc_rdma_recvfrom to rdma_rw API
Clean up: Registration mode details are now handled by the rdma_rw
API, and thus can be removed from svcrdma.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-07-12 15:54:59 -04:00
Chuck Lever 0d956e694a svcrdma: Clean-up svc_rdma_unmap_dma
There's no longer a need to compare each SGE's lkey with the PD's
local_dma_lkey. Now that FRWR is gone, all DMA mappings are for
pages that were registered with this key.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-07-12 15:54:58 -04:00
Chuck Lever 463e63d701 svcrdma: Remove frmr cache
Clean up: Now that the svc_rdma_recvfrom path uses the rdma_rw API,
the details of Read sink buffer registration are dealt with by the
kernel's RDMA core. This cache is no longer used, and can be
removed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-07-12 15:54:58 -04:00
Chuck Lever c84dc900d7 svcrdma: Remove unused Read completion handlers
Clean up:

The generic RDMA R/W API conversion of svc_rdma_recvfrom replaced
the Register, Read, and Invalidate completion handlers. Remove the
old ones, which are no longer used.

These handlers shared some helper code with svc_rdma_wc_send. Fold
the wc_common helper back into the one remaining completion handler.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-07-12 15:54:57 -04:00
Chuck Lever cafc739892 svcrdma: Use generic RDMA R/W API in RPC Call path
The current svcrdma recvfrom code path has a lot of detail about
registration mode and the type of port (iWARP, IB, etc).

Instead, use the RDMA core's generic R/W API. This shares code with
other RDMA-enabled ULPs that manages the gory details of buffer
registration and the posting of RDMA Read Work Requests.

Since the Read list marshaling code is being replaced, I took the
opportunity to replace C structure-based XDR encoding code with more
portable code that uses pointer arithmetic.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-07-12 15:54:56 -04:00
Chuck Lever 2cf32924c6 svcrdma: Remove the req_map cache
req_maps are no longer used by the send path and can thus be removed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 17:25:55 -04:00
Chuck Lever 68cc4636bb svcrdma: Remove unused RDMA Write completion handler
Clean up. All RDMA Write completions are now handled by
svc_rdma_wc_write_ctx.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 17:25:55 -04:00
Chuck Lever 9a6a180b78 svcrdma: Use rdma_rw API in RPC reply path
The current svcrdma sendto code path posts one RDMA Write WR at a
time. Each of these Writes typically carries a small number of pages
(for instance, up to 30 pages for mlx4 devices). That means a 1MB
NFS READ reply requires 9 ib_post_send() calls for the Write WRs,
and one for the Send WR carrying the actual RPC Reply message.

Instead, use the new rdma_rw API. The details of Write WR chain
construction and memory registration are taken care of in the RDMA
core. svcrdma can focus on the details of the RPC-over-RDMA
protocol. This gives three main benefits:

1. All Write WRs for one RDMA segment are posted in a single chain.
As few as one ib_post_send() for each Write chunk.

2. The Write path can now use FRWR to register the Write buffers.
If the device's maximum page list depth is large, this means a
single Write WR is needed for each RPC's Write chunk data.

3. The new code introduces support for RPCs that carry both a Write
list and a Reply chunk. This combination can be used for an NFSv4
READ where the data payload is large, and thus is removed from the
Payload Stream, but the Payload Stream is still larger than the
inline threshold.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 17:25:55 -04:00
Chuck Lever f13193f50b svcrdma: Introduce local rdma_rw API helpers
The plan is to replace the local bespoke code that constructs and
posts RDMA Read and Write Work Requests with calls to the rdma_rw
API. This shares code with other RDMA-enabled ULPs that manages the
gory details of buffer registration and posting Work Requests.

Some design notes:

 o The structure of RPC-over-RDMA transport headers is flexible,
   allowing multiple segments per Reply with arbitrary alignment,
   each with a unique R_key. Write and Send WRs continue to be
   built and posted in separate code paths. However, one whole
   chunk (with one or more RDMA segments apiece) gets exactly
   one ib_post_send and one work completion.

 o svc_xprt reference counting is modified, since a chain of
   rdma_rw_ctx structs generates one completion, no matter how
   many Write WRs are posted.

 o The current code builds the transport header as it is construct-
   ing Write WRs. I've replaced that with marshaling of transport
   header data items in a separate step. This is because the exact
   structure of client-provided segments may not align with the
   components of the server's reply xdr_buf, or the pages in the
   page list. Thus parts of each client-provided segment may be
   written at different points in the send path.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 17:25:55 -04:00
Chuck Lever b623589dba svcrdma: Eliminate RPCRDMA_SQ_DEPTH_MULT
The Send Queue depth is temporarily reduced to 1 SQE per credit. The
new rdma_rw API does an internal computation, during QP creation, to
increase the depth of the Send Queue to handle RDMA Read and Write
operations.

This change has to come before the NFSD code paths are updated to
use the rdma_rw API. Without this patch, rdma_rw_init_qp() increases
the size of the SQ too much, resulting in memory allocation failures
during QP creation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 17:25:54 -04:00
Chuck Lever 23abec20aa svcrdma: set XPT_CONG_CTRL flag for bc xprt
Same change as Kinglong Mee's fix for the TCP backchannel service.

Fixes: 5283b03ee5 ("nfs/nfsd/sunrpc: enforce transport...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-03-28 21:25:55 -04:00
Linus Torvalds 8313064c2e The nfsd update this round is mainly a lot of miscellaneous cleanups and
bugfixes.
 
 A couple changes could theoretically break working setups on upgrade.  I
 don't expect complaints in practice, but they seem worth calling out
 just in case:
 
 	- NFS security labels are now off by default; a new
 	  security_label export flag reenables it per export.  But,
 	  having them on by default is a disaster, as it generally only
 	  makes sense if all your clients and servers have similar
 	  enough selinux policies.  Thanks to Jason Tibbitts for
 	  pointing this out.
 
 	- NFSv4/UDP support is off.  It was never really supported, and
 	  the spec explicitly forbids it.  We only ever left it on out
 	  of laziness; thanks to Jeff Layton for finally fixing that.
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Merge tag 'nfsd-4.11' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "The nfsd update this round is mainly a lot of miscellaneous cleanups
  and bugfixes.

  A couple changes could theoretically break working setups on upgrade.
  I don't expect complaints in practice, but they seem worth calling out
  just in case:

   - NFS security labels are now off by default; a new security_label
     export flag reenables it per export. But, having them on by default
     is a disaster, as it generally only makes sense if all your clients
     and servers have similar enough selinux policies. Thanks to Jason
     Tibbitts for pointing this out.

   - NFSv4/UDP support is off. It was never really supported, and the
     spec explicitly forbids it. We only ever left it on out of
     laziness; thanks to Jeff Layton for finally fixing that"

* tag 'nfsd-4.11' of git://linux-nfs.org/~bfields/linux: (34 commits)
  nfsd: Fix display of the version string
  nfsd: fix configuration of supported minor versions
  sunrpc: don't register UDP port with rpcbind when version needs congestion control
  nfs/nfsd/sunrpc: enforce transport requirements for NFSv4
  sunrpc: flag transports as having congestion control
  sunrpc: turn bitfield flags in svc_version into bools
  nfsd: remove superfluous KERN_INFO
  nfsd: special case truncates some more
  nfsd: minor nfsd_setattr cleanup
  NFSD: Reserve adequate space for LOCKT operation
  NFSD: Get response size before operation for all RPCs
  nfsd/callback: Drop a useless data copy when comparing sessionid
  nfsd/callback: skip the callback tag
  nfsd/callback: Cleanup callback cred on shutdown
  nfsd/idmap: return nfserr_inval for 0-length names
  SUNRPC/Cache: Always treat the invalid cache as unexpired
  SUNRPC: Drop all entries from cache_detail when cache_purge()
  svcrdma: Poll CQs in "workqueue" mode
  svcrdma: Combine list fields in struct svc_rdma_op_ctxt
  svcrdma: Remove unused sc_dto_q field
  ...
2017-02-28 15:39:09 -08:00
Jeff Layton 362142b258 sunrpc: flag transports as having congestion control
NFSv4 requires a transport protocol with congestion control in most
cases.

On an IP network, that means that NFSv4 over UDP should be forbidden.

The situation with RDMA is a bit more nuanced, but most RDMA transports
are suitable for this. For now, we assume that all RDMA transports are
suitable, but we may need to revise that at some point.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-24 16:55:46 -05:00
Chuck Lever 81fa3275f9 svcrdma: Poll CQs in "workqueue" mode
svcrdma calls svc_xprt_put() in its completion handlers, which
currently run in IRQ context.

However, svc_xprt_put() is meant to be invoked in process context,
not in IRQ context. After the last transport reference is gone, it
directly calls a transport release function that expects to run in
process context.

Change the CQ polling modes to IB_POLL_WORKQUEUE so that svcrdma
invokes svc_xprt_put() only in process context. As an added benefit,
bottom half-disabled spin locking can be eliminated from I/O paths.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08 14:42:01 -05:00
Chuck Lever a3ab867fa6 svcrdma: Combine list fields in struct svc_rdma_op_ctxt
Clean up: The free list and the dto_q list fields are never used at
the same time. Reduce the size of struct svc_rdma_op_ctxt by
combining these fields.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08 14:42:00 -05:00
Chuck Lever aba7d14ba1 svcrdma: Remove unused sc_dto_q field
Clean up. Commit be99bb1140 ("svcrdma: Use new CQ API for
RPC-over-RDMA server send CQs") removed code that used the sc_dto_q
field, but neglected to remove sc_dto_q at the same time.

Fixes: be99bb1140 ("svcrdma: Use new CQ API for RPC-over- ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08 14:41:59 -05:00
Chuck Lever 98fc21d3bf svcrdma: Clean up RPC-over-RDMA Reply header encoder
Replace C structure-based XDR decoding with pointer arithmetic.
Pointer arithmetic is considered more portable, and is used
throughout the kernel's existing XDR encoders. The gcc optimizer
generates similar assembler code either way.

Byte-swapping before a memory store on x86 typically results in an
instruction pipeline stall. Avoid byte-swapping when encoding a new
header.

svcrdma currently doesn't alter a connection's credit grant value
after the connection has been accepted, so it is effectively a
constant. Cache the byte-swapped value in a separate field.

Christoph suggested pulling the header encoding logic into the only
function that uses it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08 14:41:41 -05:00
Peter Zijlstra 2c935bc572 locking/atomic, kref: Add kref_read()
Since we need to change the implementation, stop exposing internals.

Provide kref_read() to read the current reference count; typically
used for debug messages.

Kills two anti-patterns:

	atomic_read(&kref->refcount)
	kref->refcount.counter

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
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>
2017-01-14 11:37:18 +01:00
Linus Torvalds 759b2656b2 The one new feature is support for a new NFSv4.2 mode_umask attribute
that makes ACL inheritance a little more useful in environments that
 default to restrictive umasks.  Requires client-side support, also on
 its way for 4.10.
 
 Other than that, miscellaneous smaller fixes and cleanup, especially to
 the server rdma code.
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Merge tag 'nfsd-4.10' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "The one new feature is support for a new NFSv4.2 mode_umask attribute
  that makes ACL inheritance a little more useful in environments that
  default to restrictive umasks. Requires client-side support, also on
  its way for 4.10.

  Other than that, miscellaneous smaller fixes and cleanup, especially
  to the server rdma code"

[ The client side of the umask attribute was merged yesterday ]

* tag 'nfsd-4.10' of git://linux-nfs.org/~bfields/linux:
  nfsd: add support for the umask attribute
  sunrpc: use DEFINE_SPINLOCK()
  svcrdma: Further clean-up of svc_rdma_get_inv_rkey()
  svcrdma: Break up dprintk format in svc_rdma_accept()
  svcrdma: Remove unused variable in rdma_copy_tail()
  svcrdma: Remove unused variables in xprt_rdma_bc_allocate()
  svcrdma: Remove svc_rdma_op_ctxt::wc_status
  svcrdma: Remove DMA map accounting
  svcrdma: Remove BH-disabled spin locking in svc_rdma_send()
  svcrdma: Renovate sendto chunk list parsing
  svcauth_gss: Close connection when dropping an incoming message
  svcrdma: Clear xpt_bc_xps in xprt_setup_rdma_bc() error exit arm
  nfsd: constify reply_cache_stats_operations structure
  nfsd: update workqueue creation
  sunrpc: GFP_KERNEL should be GFP_NOFS in crypto code
  nfsd: catch errors in decode_fattr earlier
  nfsd: clean up supported attribute handling
  nfsd: fix error handling for clients that fail to return the layout
  nfsd: more robust allocation failure handling in nfsd_reply_cache_init
2016-12-16 10:48:28 -08:00
Chuck Lever 0725745020 svcrdma: Break up dprintk format in svc_rdma_accept()
The current code results in:

Nov  7 14:50:19 klimt kernel: svcrdma: newxprt->sc_cm_id=ffff88085590c800,
 newxprt->sc_pd=ffff880852a7ce00#012    cm_id->device=ffff88084dd20000,
 sc_pd->device=ffff88084dd20000#012    cap.max_send_wr = 272#012
 cap.max_recv_wr = 34#012    cap.max_send_sge = 32#012
 cap.max_recv_sge = 32
Nov  7 14:50:19 klimt kernel: svcrdma: new connection ffff880855908000
 accepted with the following attributes:#012    local_ip        :
 10.0.0.5#012    local_port#011     : 20049#012    remote_ip       :
 10.0.0.2#012    remote_port     : 59909#012    max_sge         : 32#012
 max_sge_rd      : 30#012    sq_depth        : 272#012    max_requests    :
 32#012    ord             : 16

Split up the output over multiple dprintks and take the opportunity
to fix the display of IPv6 addresses.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30 17:31:16 -05:00
Chuck Lever 96a58f9c19 svcrdma: Remove svc_rdma_op_ctxt::wc_status
Clean up: Completion status is already reported in the individual
completion handlers. Save a few bytes in struct svc_rdma_op_ctxt.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30 17:31:14 -05:00
Chuck Lever dd6fd213b0 svcrdma: Remove DMA map accounting
Clean up: sc_dma_used is not required for correct operation. It is
simply a debugging tool to report when svcrdma has leaked DMA maps.

However, manipulating an atomic has a measurable CPU cost, and DMA
map accounting specific to svcrdma will be meaningless once svcrdma
is converted to use the new generic r/w API.

A similar kind of debug accounting can be done simply by enabling
the IOMMU or by using CONFIG_DMA_API_DEBUG, CONFIG_IOMMU_DEBUG, and
CONFIG_IOMMU_LEAK.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30 17:31:13 -05:00
Chuck Lever e4eb42cecc svcrdma: Remove BH-disabled spin locking in svc_rdma_send()
svcrdma's current SQ accounting algorithm takes sc_lock and disables
bottom-halves while posting all RDMA Read, Write, and Send WRs.

This is relatively heavyweight serialization. And note that Write and
Send are already fully serialized by the xpt_mutex.

Using a single atomic_t should be all that is necessary to guarantee
that ib_post_send() is called only when there is enough space on the
send queue. This is what the other RDMA-enabled storage targets do.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30 17:31:13 -05:00
Scott Mayhew ea08e39230 sunrpc: svc_age_temp_xprts_now should not call setsockopt non-tcp transports
This fixes the following panic that can occur with NFSoRDMA.

general protection fault: 0000 [#1] SMP
Modules linked in: rpcrdma ib_isert iscsi_target_mod ib_iser libiscsi
scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp
scsi_tgt ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm
mlx5_ib ib_core intel_powerclamp coretemp kvm_intel kvm sg ioatdma
ipmi_devintf ipmi_ssif dcdbas iTCO_wdt iTCO_vendor_support pcspkr
irqbypass sb_edac shpchp dca crc32_pclmul ghash_clmulni_intel edac_core
lpc_ich aesni_intel lrw gf128mul glue_helper ablk_helper mei_me mei
ipmi_si cryptd wmi ipmi_msghandler acpi_pad acpi_power_meter nfsd
auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod
crc_t10dif crct10dif_generic mgag200 i2c_algo_bit drm_kms_helper
syscopyarea sysfillrect sysimgblt ahci fb_sys_fops ttm libahci mlx5_core
tg3 crct10dif_pclmul drm crct10dif_common
ptp i2c_core libata crc32c_intel pps_core fjes dm_mirror dm_region_hash
dm_log dm_mod
CPU: 1 PID: 120 Comm: kworker/1:1 Not tainted 3.10.0-514.el7.x86_64 #1
Hardware name: Dell Inc. PowerEdge R320/0KM5PX, BIOS 2.4.2 01/29/2015
Workqueue: events check_lifetime
task: ffff88031f506dd0 ti: ffff88031f584000 task.ti: ffff88031f584000
RIP: 0010:[<ffffffff8168d847>]  [<ffffffff8168d847>]
_raw_spin_lock_bh+0x17/0x50
RSP: 0018:ffff88031f587ba8  EFLAGS: 00010206
RAX: 0000000000020000 RBX: 20041fac02080072 RCX: ffff88031f587fd8
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 20041fac02080072
RBP: ffff88031f587bb0 R08: 0000000000000008 R09: ffffffff8155be77
R10: ffff880322a59b00 R11: ffffea000bf39f00 R12: 20041fac02080072
R13: 000000000000000d R14: ffff8800c4fbd800 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff880322a40000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3c52d4547e CR3: 00000000019ba000 CR4: 00000000001407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
20041fac02080002 ffff88031f587bd0 ffffffff81557830 20041fac02080002
ffff88031f587c78 ffff88031f587c40 ffffffff8155ae08 000000010157df32
0000000800000001 ffff88031f587c20 ffffffff81096acb ffffffff81aa37d0
Call Trace:
[<ffffffff81557830>] lock_sock_nested+0x20/0x50
[<ffffffff8155ae08>] sock_setsockopt+0x78/0x940
[<ffffffff81096acb>] ? lock_timer_base.isra.33+0x2b/0x50
[<ffffffff8155397d>] kernel_setsockopt+0x4d/0x50
[<ffffffffa0386284>] svc_age_temp_xprts_now+0x174/0x1e0 [sunrpc]
[<ffffffffa03b681d>] nfsd_inetaddr_event+0x9d/0xd0 [nfsd]
[<ffffffff81691ebc>] notifier_call_chain+0x4c/0x70
[<ffffffff810b687d>] __blocking_notifier_call_chain+0x4d/0x70
[<ffffffff810b68b6>] blocking_notifier_call_chain+0x16/0x20
[<ffffffff815e8538>] __inet_del_ifa+0x168/0x2d0
[<ffffffff815e8cef>] check_lifetime+0x25f/0x270
[<ffffffff810a7f3b>] process_one_work+0x17b/0x470
[<ffffffff810a8d76>] worker_thread+0x126/0x410
[<ffffffff810a8c50>] ? rescuer_thread+0x460/0x460
[<ffffffff810b052f>] kthread+0xcf/0xe0
[<ffffffff810b0460>] ? kthread_create_on_node+0x140/0x140
[<ffffffff81696418>] ret_from_fork+0x58/0x90
[<ffffffff810b0460>] ? kthread_create_on_node+0x140/0x140
Code: ca 75 f1 5d c3 0f 1f 80 00 00 00 00 eb d9 66 0f 1f 44 00 00 0f 1f
44 00 00 55 48 89 e5 53 48 89 fb e8 7e 04 a0 ff b8 00 00 02 00 <f0> 0f
c1 03 89 c2 c1 ea 10 66 39 c2 75 03 5b 5d c3 83 e2 fe 0f
RIP  [<ffffffff8168d847>] _raw_spin_lock_bh+0x17/0x50
RSP <ffff88031f587ba8>

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Fixes: c3d4879e ("sunrpc: Add a function to close temporary transports immediately")
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-14 10:30:58 -05:00
Linus Torvalds 2778556474 Some RDMA work and some good bugfixes, and two new features that could
benefit from user testing:
 
 Anna Schumacker contributed a simple NFSv4.2 COPY implementation.  COPY
 is already supported on the client side, so a call to copy_file_range()
 on a recent client should now result in a server-side copy that doesn't
 require all the data to make a round trip to the client and back.
 
 Jeff Layton implemented callbacks to notify clients when contended locks
 become available, which should reduce latency on workloads with
 contended locks.
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Merge tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Some RDMA work and some good bugfixes, and two new features that could
  benefit from user testing:

   - Anna Schumacker contributed a simple NFSv4.2 COPY implementation.
     COPY is already supported on the client side, so a call to
     copy_file_range() on a recent client should now result in a
     server-side copy that doesn't require all the data to make a round
     trip to the client and back.

   - Jeff Layton implemented callbacks to notify clients when contended
     locks become available, which should reduce latency on workloads
     with contended locks"

* tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linux:
  NFSD: Implement the COPY call
  nfsd: handle EUCLEAN
  nfsd: only WARN once on unmapped errors
  exportfs: be careful to only return expected errors.
  nfsd4: setclientid_confirm with unmatched verifier should fail
  nfsd: randomize SETCLIENTID reply to help distinguish servers
  nfsd: set the MAY_NOTIFY_LOCK flag in OPEN replies
  nfs: add a new NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK constant
  nfsd: add a LRU list for blocked locks
  nfsd: have nfsd4_lock use blocking locks for v4.1+ locks
  nfsd: plumb in a CB_NOTIFY_LOCK operation
  NFSD: fix corruption in notifier registration
  svcrdma: support Remote Invalidation
  svcrdma: Server-side support for rpcrdma_connect_private
  rpcrdma: RDMA/CM private message data structure
  svcrdma: Skip put_page() when send_reply() fails
  svcrdma: Tail iovec leaves an orphaned DMA mapping
  nfsd: fix dprintk in nfsd4_encode_getdeviceinfo
  nfsd: eliminate cb_minorversion field
  nfsd: don't set a FL_LAYOUT lease for flexfiles layouts
2016-10-13 21:04:42 -07:00
Christoph Hellwig ed082d36a7 IB/core: add support to create a unsafe global rkey to ib_create_pd
Instead of exposing ib_get_dma_mr to ULPs and letting them use it more or
less unchecked, this moves the capability of creating a global rkey into
the RDMA core, where it can be easily audited.  It also prints a warning
everytime this feature is used as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-09-23 13:47:44 -04:00
Chuck Lever 25d55296dd svcrdma: support Remote Invalidation
Support Remote Invalidation. A private message is exchanged with
the client upon RDMA transport connect that indicates whether
Send With Invalidation may be used by the server to send RPC
replies. The invalidate_rkey is arbitrarily chosen from among
rkeys present in the RPC-over-RDMA header's chunk lists.

Send With Invalidate improves performance only when clients can
recognize, while processing an RPC reply, that an rkey has already
been invalidated. That has been submitted as a separate change.

In the future, the RPC-over-RDMA protocol might support Remote
Invalidation properly. The protocol needs to enable signaling
between peers to indicate when Remote Invalidation can be used
for each individual RPC.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-23 10:18:54 -04:00
Chuck Lever cc9d83408b svcrdma: Server-side support for rpcrdma_connect_private
Prepare to receive an RDMA-CM private message when handling a new
connection attempt, and send a similar message as part of connection
acceptance.

Both sides can communicate their various implementation limits.
Implementations that don't support this sideband protocol ignore it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-23 10:18:54 -04:00
Chuck Lever cace564f8b svcrdma: Tail iovec leaves an orphaned DMA mapping
The ctxt's count field is overloaded to mean the number of pages in
the ctxt->page array and the number of SGEs in the ctxt->sge array.
Typically these two numbers are the same.

However, when an inline RPC reply is constructed from an xdr_buf
with a tail iovec, the head and tail often occupy the same page,
but each are DMA mapped independently. In that case, ->count equals
the number of pages, but it does not equal the number of SGEs.
There's one more SGE, for the tail iovec. Hence there is one more
DMA mapping than there are pages in the ctxt->page array.

This isn't a real problem until the server's iommu is enabled. Then
each RPC reply that has content in that iovec orphans a DMA mapping
that consists of real resources.

krb5i and krb5p always populate that tail iovec. After a couple
million sent krb5i/p RPC replies, the NFS server starts behaving
erratically. Reboot is needed to clear the problem.

Fixes: 9d11b51ce7 ("svcrdma: Fix send_reply() scatter/gather set-up")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-23 10:18:52 -04:00
Chuck Lever 76ee8fd64a svcrdma: Drain QP before freeing svcrdma_xprt
If the server has forced a disconnect, the associated QP has not
been moved to the Error state, and thus Receives are still posted.

Ensure Receives (and any other outstanding WRs) are drained to
release resources that can be freed during teardown of the
svcrdma_xprt.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-05-13 15:53:06 -04:00
Chuck Lever 0319aafc95 svcrdma: Post Receives only for forward channel requests
Since backward direction support was added, the rq_depth was
increased to accommodate both forward and backward Receives.

But only forward Receives need to be posted after a connection
has been accepted. Receives for backward replies are posted as
needed by svc_rdma_bc_sendto().

This doesn't break anything, but it means some resources are
wasted.

Fixes: 03fe993153 ('svcrdma: Define maximum number of ...')
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-05-13 15:53:06 -04:00
Shirley Ma 696190eaf1 svcrdma: Support IPv6 with NFS/RDMA
Allow both IPv4 and IPv6 to bind same port at the same time,
restricts use of the IPv6 socket to IPv6 communication.

Changes from v1:
 - Check rdma_set_afonly return value (suggested by Leon Romanovsky)

Changes from v2:
 - Acked-by: Leon Romanovsky <leonro@mellanox.com>

Signed-off-by: Shirley Ma <shirley.ma@oracle.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-05-13 15:53:05 -04:00
Chuck Lever be99bb1140 svcrdma: Use new CQ API for RPC-over-RDMA server send CQs
Calling ib_poll_cq() to sort through WCs during a completion is a
common pattern amongst RDMA consumers. Since commit 14d3a3b249
("IB: add a proper completion queue abstraction"), WC sorting can
be handled by the IB core.

By converting to this new API, svcrdma is made a better neighbor to
other RDMA consumers, as it allows the core to schedule the delivery
of completions more fairly amongst all active consumers.

This new API also aims each completion at a function that is
specific to the WR's opcode. Thus the ctxt->wr_op field and the
switch in process_context is replaced by a set of methods that
handle each completion type.

Because each ib_cqe carries a pointer to a completion method, the
core can now post operations on a consumer's QP, and handle the
completions itself.

The server's rdma_stat_sq_poll and rdma_stat_sq_prod metrics are no
longer updated.

As a clean up, the cq_event_handler, the dto_tasklet, and all
associated locking is removed, as they are no longer referenced or
used.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-03-01 13:06:43 -08:00