Trond Myklebust reports an NFSD crash in svc_rdma_sendto(). Further
investigation shows that the crash occurred while NFSD was handling
a deferred request.
This patch addresses two inter-related issues that prevent request
deferral from working correctly for RPC/RDMA requests:
1. Prevent the crash by ensuring that the original
svc_rqst::rq_xprt_ctxt value is available when the request is
revisited. Otherwise svc_rdma_sendto() does not have a Receive
context available with which to construct its reply.
2. Possibly since before commit 71641d99ce ("svcrdma: Properly
compute .len and .buflen for received RPC Calls"),
svc_rdma_recvfrom() did not include the transport header in the
returned xdr_buf. There should have been no need for svc_defer()
and friends to save and restore that header, as of that commit.
This issue is addressed in a backport-friendly way by simply
having svc_rdma_recvfrom() set rq_xprt_hlen to zero
unconditionally, just as svc_tcp_recvfrom() does. This enables
svc_deferred_recv() to correctly reconstruct an RPC message
received via RPC/RDMA.
Reported-by: Trond Myklebust <trondmy@hammerspace.com>
Link: https://lore.kernel.org/linux-nfs/82662b7190f26fb304eb0ab1bb04279072439d4e.camel@hammerspace.com/
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org>
Highlights include:
Features:
- Switch NFS to use readahead instead of the obsolete readpages.
- Readdir fixes to improve cacheability of large directories when there
are multiple readers and writers.
- Readdir performance improvements when doing a seekdir() immediately
after opening the directory (common when re-exporting NFS).
- NFS swap improvements from Neil Brown.
- Loosen up memory allocation to permit direct reclaim and write back
in cases where there is no danger of deadlocking the writeback code or
NFS swap.
- Avoid sillyrename when the NFSv4 server claims to support the
necessary features to recover the unlinked but open file after reboot.
Bugfixes:
- Patch from Olga to add a mount option to control NFSv4.1 session
trunking discovery, and default it to being off.
- Fix a lockup in nfs_do_recoalesce().
- Two fixes for list iterator variables being used when pointing to the
list head.
- Fix a kernel memory scribble when reading from a non-socket transport
in /sys/kernel/sunrpc.
- Fix a race where reconnecting to a server could leave the TCP socket
stuck forever in the connecting state.
- Patch from Neil to fix a shutdown race which can leave the SUNRPC
transport timer primed after we free the struct xprt itself.
- Patch from Xin Xiong to fix reference count leaks in the NFSv4.2 copy
offload.
- Sunrpc patch from Olga to avoid resending a task on an offlined
transport.
Cleanups:
- Patches from Dave Wysochanski to clean up the fscache code
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Merge tag 'nfs-for-5.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Features:
- Switch NFS to use readahead instead of the obsolete readpages.
- Readdir fixes to improve cacheability of large directories when
there are multiple readers and writers.
- Readdir performance improvements when doing a seekdir() immediately
after opening the directory (common when re-exporting NFS).
- NFS swap improvements from Neil Brown.
- Loosen up memory allocation to permit direct reclaim and write back
in cases where there is no danger of deadlocking the writeback code
or NFS swap.
- Avoid sillyrename when the NFSv4 server claims to support the
necessary features to recover the unlinked but open file after
reboot.
Bugfixes:
- Patch from Olga to add a mount option to control NFSv4.1 session
trunking discovery, and default it to being off.
- Fix a lockup in nfs_do_recoalesce().
- Two fixes for list iterator variables being used when pointing to
the list head.
- Fix a kernel memory scribble when reading from a non-socket
transport in /sys/kernel/sunrpc.
- Fix a race where reconnecting to a server could leave the TCP
socket stuck forever in the connecting state.
- Patch from Neil to fix a shutdown race which can leave the SUNRPC
transport timer primed after we free the struct xprt itself.
- Patch from Xin Xiong to fix reference count leaks in the NFSv4.2
copy offload.
- Sunrpc patch from Olga to avoid resending a task on an offlined
transport.
Cleanups:
- Patches from Dave Wysochanski to clean up the fscache code"
* tag 'nfs-for-5.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (91 commits)
NFSv4/pNFS: Fix another issue with a list iterator pointing to the head
NFS: Don't loop forever in nfs_do_recoalesce()
SUNRPC: Don't return error values in sysfs read of closed files
SUNRPC: Do not dereference non-socket transports in sysfs
NFSv4.1: don't retry BIND_CONN_TO_SESSION on session error
SUNRPC don't resend a task on an offlined transport
NFS: replace usage of found with dedicated list iterator variable
SUNRPC: avoid race between mod_timer() and del_timer_sync()
pNFS/files: Ensure pNFS allocation modes are consistent with nfsiod
pNFS/flexfiles: Ensure pNFS allocation modes are consistent with nfsiod
NFSv4/pnfs: Ensure pNFS allocation modes are consistent with nfsiod
NFS: Avoid writeback threads getting stuck in mempool_alloc()
NFS: nfsiod should not block forever in mempool_alloc()
SUNRPC: Make the rpciod and xprtiod slab allocation modes consistent
SUNRPC: Fix unx_lookup_cred() allocation
NFS: Fix memory allocation in rpc_alloc_task()
NFS: Fix memory allocation in rpc_malloc()
SUNRPC: Improve accuracy of socket ENOBUFS determination
SUNRPC: Replace internal use of SOCKWQ_ASYNC_NOSPACE
SUNRPC: Fix socket waits for write buffer space
...
rpc tasks can be marked as RPC_TASK_SWAPPER. This causes GFP_MEMALLOC
to be used for some allocations. This is needed in some cases, but not
in all where it is currently provided, and in some where it isn't
provided.
Currently *all* tasks associated with a rpc_client on which swap is
enabled get the flag and hence some GFP_MEMALLOC support.
GFP_MEMALLOC is provided for ->buf_alloc() but only swap-writes need it.
However xdr_alloc_bvec does not get GFP_MEMALLOC - though it often does
need it.
xdr_alloc_bvec is called while the XPRT_LOCK is held. If this blocks,
then it blocks all other queued tasks. So this allocation needs
GFP_MEMALLOC for *all* requests, not just writes, when the xprt is used
for any swap writes.
Similarly, if the transport is not connected, that will block all
requests including swap writes, so memory allocations should get
GFP_MEMALLOC if swap writes are possible.
So with this patch:
1/ we ONLY set RPC_TASK_SWAPPER for swap writes.
2/ __rpc_execute() sets PF_MEMALLOC while handling any task
with RPC_TASK_SWAPPER set, or when handling any task that
holds the XPRT_LOCKED lock on an xprt used for swap.
This removes the need for the RPC_IS_SWAPPER() test
in ->buf_alloc handlers.
3/ xprt_prepare_transmit() sets PF_MEMALLOC after locking
any task to a swapper xprt. __rpc_execute() will clear it.
3/ PF_MEMALLOC is set for all the connect workers.
Reviewed-by: Chuck Lever <chuck.lever@oracle.com> (for xprtrdma parts)
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When memory is short, new worker threads cannot be created and we depend
on the minimum one rpciod thread to be able to handle everything. So it
must not block waiting for memory.
xprt_dynamic_alloc_slot can block indefinitely. This can tie up all
workqueue threads and NFS can deadlock. So when called from a
workqueue, set __GFP_NORETRY.
The rdma alloc_slot already does not block. However it sets the error
to -EAGAIN suggesting this will trigger a sleep. It does not. As we
can see in call_reserveresult(), only -ENOMEM causes a sleep. -EAGAIN
causes immediate retry.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When memory is short, new worker threads cannot be created and we depend
on the minimum one rpciod thread to be able to handle everything.
So it must not block waiting for memory.
mempools are particularly a problem as memory can only be released back
to the mempool by an async rpc task running. If all available
workqueue threads are waiting on the mempool, no thread is available to
return anything.
rpc_malloc() can block, and this might cause deadlocks.
So check RPC_IS_ASYNC(), rather than RPC_IS_SWAPPER() to determine if
blocking is acceptable.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If there are failures then we must not leave the non-NULL pointers with
the error value, otherwise `rpcrdma_ep_destroy` gets confused and tries
free them, resulting in an Oops.
Signed-off-by: Dan Aloni <dan.aloni@vastdata.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Deprecated. dprintk is no longer used in xprtrdma.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Deprecated. This information is available via tracepoints.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
support for a filehandle format deprecated 20 years ago, and further
xdr-related cleanup from Chuck.
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Merge tag 'nfsd-5.16' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"A slow cycle for nfsd: mainly cleanup, including Neil's patch dropping
support for a filehandle format deprecated 20 years ago, and further
xdr-related cleanup from Chuck"
* tag 'nfsd-5.16' of git://linux-nfs.org/~bfields/linux: (26 commits)
nfsd4: remove obselete comment
nfsd: document server-to-server-copy parameters
NFSD:fix boolreturn.cocci warning
nfsd: update create verifier comment
SUNRPC: Change return value type of .pc_encode
SUNRPC: Replace the "__be32 *p" parameter to .pc_encode
NFSD: Save location of NFSv4 COMPOUND status
SUNRPC: Change return value type of .pc_decode
SUNRPC: Replace the "__be32 *p" parameter to .pc_decode
SUNRPC: De-duplicate .pc_release() call sites
SUNRPC: Simplify the SVC dispatch code path
SUNRPC: Capture value of xdr_buf::page_base
SUNRPC: Add trace event when alloc_pages_bulk() makes no progress
svcrdma: Split svcrmda_wc_{read,write} tracepoints
svcrdma: Split the svcrdma_wc_send() tracepoint
svcrdma: Split the svcrdma_wc_receive() tracepoint
NFSD: Have legacy NFSD WRITE decoders use xdr_stream_subsegment()
SUNRPC: xdr_stream_subsegment() must handle non-zero page_bases
NFSD: Initialize pointer ni with NULL and not plain integer 0
NFSD: simplify struct nfsfh
...
This minor fix-up keeps GCC from complaining that "last' may be used
uninitialized", which breaks some build workflows that have been running
with all warnings treated as errors.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up: this field is no longer used.
xprt_rdma_pad_optimize is also no longer used, but is left in place
because it is part of the kernel/userspace API.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This is a buffer to be left persistently registered while a
connection is up. Connection tear-down will automatically DMA-unmap,
invalidate, and dereg the MR. A persistently registered buffer is
lower in cost to provide, and it can never be coalesced into the
RDMA segment that carries the data payload.
An RPC that provisions a Write chunk with a non-aligned length now
uses this MR rather than the tail buffer of the RPC's rq_rcv_buf.
Reviewed-By: Tom Talpey <tom@talpey.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
There are currently three separate purposes being served by single
tracepoints. Split them up, as was done with wc_send.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There are currently three separate purposes being served by a single
tracepoint here. They need to be split up.
svcrdma_wc_send:
- status is always zero, so there's no value in recording it.
- vendor_err is meaningless unless status is not zero, so
there's no value in recording it.
- This tracepoint is needed only when developing modifications,
so it should be left disabled most of the time.
svcrdma_wc_send_flush:
- As above, needed only rarely, and not an error.
svcrdma_wc_send_err:
- This tracepoint can be left persistently enabled because
completion errors are run-time problems (except for FLUSHED_ERR).
- Tracepoint name now ends in _err to reflect its purpose.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There are currently three separate purposes being served by a single
tracepoint here. They need to be split up.
svcrdma_wc_recv:
- status is always zero, so there's no value in recording it.
- vendor_err is meaningless unless status is not zero, so
there's no value in recording it.
- This tracepoint is needed only when developing modifications,
so it should be left disabled most of the time.
svcrdma_wc_recv_flush:
- As above, needed only rarely, and not an error.
svcrdma_wc_recv_err:
- received is always zero, so there's no value in recording it.
- This tracepoint can be left enabled because completion
errors are run-time problems (except for FLUSHED_ERR).
- Tracepoint name now ends in _err to reflect its purpose.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
- New Features:
- Better client responsiveness when server isn't replying
- Use refcount_t in sunrpc rpc_client refcount tracking
- Add srcaddr and dst_port to the sunrpc sysfs info files
- Add basic support for connection sharing between servers with multiple NICs`
- Bugfixes and Cleanups:
- Sunrpc tracepoint cleanups
- Disconnect after ib_post_send() errors to avoid deadlocks
- Fix for tearing down rpcrdma_reps
- Fix a potential pNFS layoutget livelock loop
- pNFS layout barrier fixes
- Fix a potential memory corruption in rpc_wake_up_queued_task_set_status()
- Fix reconnection locking
- Fix return value of get_srcport()
- Remove rpcrdma_post_sends()
- Remove pNFS dead code
- Remove copy size restriction for inter-server copies
- Overhaul the NFS callback service
- Clean up sunrpc TCP socket shutdowns
- Always provide aligned buffers to RPC read layers
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Merge tag 'nfs-for-5.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"New Features:
- Better client responsiveness when server isn't replying
- Use refcount_t in sunrpc rpc_client refcount tracking
- Add srcaddr and dst_port to the sunrpc sysfs info files
- Add basic support for connection sharing between servers with multiple NICs`
Bugfixes and Cleanups:
- Sunrpc tracepoint cleanups
- Disconnect after ib_post_send() errors to avoid deadlocks
- Fix for tearing down rpcrdma_reps
- Fix a potential pNFS layoutget livelock loop
- pNFS layout barrier fixes
- Fix a potential memory corruption in rpc_wake_up_queued_task_set_status()
- Fix reconnection locking
- Fix return value of get_srcport()
- Remove rpcrdma_post_sends()
- Remove pNFS dead code
- Remove copy size restriction for inter-server copies
- Overhaul the NFS callback service
- Clean up sunrpc TCP socket shutdowns
- Always provide aligned buffers to RPC read layers"
* tag 'nfs-for-5.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (39 commits)
NFS: Always provide aligned buffers to the RPC read layers
NFSv4.1 add network transport when session trunking is detected
SUNRPC enforce creation of no more than max_connect xprts
NFSv4 introduce max_connect mount options
SUNRPC add xps_nunique_destaddr_xprts to xprt_switch_info in sysfs
SUNRPC keep track of number of transports to unique addresses
NFSv3: Delete duplicate judgement in nfs3_async_handle_jukebox
SUNRPC: Tweak TCP socket shutdown in the RPC client
SUNRPC: Simplify socket shutdown when not reusing TCP ports
NFSv4.2: remove restriction of copy size for inter-server copy.
NFS: Clean up the synopsis of callback process_op()
NFS: Extract the xdr_init_encode/decode() calls from decode_compound
NFS: Remove unused callback void decoder
NFS: Add a private local dispatcher for NFSv4 callback operations
SUNRPC: Eliminate the RQ_AUTHERR flag
SUNRPC: Set rq_auth_stat in the pg_authenticate() callout
SUNRPC: Add svc_rqst::rq_auth_stat
SUNRPC: Add dst_port to the sysfs xprt info file
SUNRPC: Add srcaddr as a file in sysfs
sunrpc: Fix return value of get_srcport()
...
svc_xprt_free() already "puts" the bc_xprt before calling the
transport's "free" method. No need to do it twice.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Relieve contention on sc_rw_ctxt_lock by converting rdma->sc_rw_ctxts
to an llist.
The goal is to reduce the average overhead of Send completions,
because a transport's completion handlers are single-threaded on
one CPU core. This change reduces CPU utilization of each Send
completion by 2-3% on my server.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-By: Tom Talpey <tom@talpey.com>
/proc/lock_stat indicates the the sc_send_lock is heavily
contended when the server is under load from a single client.
To address this, convert the send_ctxt free list to an llist.
Returning an item to the send_ctxt cache is now waitless, which
reduces the instruction path length in the single-threaded Send
handler (svc_rdma_wc_send).
The goal is to enable the ib_comp_wq worker to handle a higher
RPC/RDMA Send completion rate given the same CPU resources. This
change reduces CPU utilization of Send completion by 2-3% on my
server.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-By: Tom Talpey <tom@talpey.com>
Because wake_up() takes an IRQ-safe lock, it can be expensive,
especially to call inside of a single-threaded completion handler.
What's more, the Send wait queue almost never has waiters, so
most of the time, this is an expensive no-op.
As always, the goal is to reduce the average overhead of each
completion, because a transport's completion handlers are single-
threaded on one CPU core. This change reduces CPU utilization of
the Send completion thread by 2-3% on my server.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-By: Tom Talpey <tom@talpey.com>
The xprtrdma client code currently relies on the task that initiated the
connect to hold the XPRT_LOCK for the duration of the connection
attempt. If the task is woken early, due to some other event, then that
lock could get released early.
Avoid races by using the same mechanism that the socket code uses of
transferring lock ownership to the RDMA connect worker itself. That
frees us to call rpcrdma_xprt_disconnect() directly since we're now
guaranteed exclusion w.r.t. other callers.
Fixes: 4cf44be6f1 ("xprtrdma: Fix recursion into rpcrdma_xprt_disconnect()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up.
Now that there is only one registration mode, there is only one
target "post_send" method: frwr_send(). rpcrdma_post_sends() no
longer adds much value, especially since all of its call sites
ignore the return code value except to check if it's non-zero.
Just have them call frwr_send() directly instead.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Unlike xprtrdma_post_send(), this one can be left enabled all the
time, and should almost never fire. But we do want to know about
immediate errors when they happen.
Note that there is already a similar post_linv_err tracepoint.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In the vast majority of cases, rc=0. Don't record that in the
post_recvs tracepoint. Instead, add a separate tracepoint that can
be left enabled all the time to capture the very rare immediate
errors returned by ib_post_recv().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Ensure the tear-down completion is awoken only /after/ we've stopped
fiddling with rpcrdma_rep objects in rpcrdma_post_recvs().
Fixes: 15788d1d10 ("xprtrdma: Do not refresh Receive Queue while it is draining")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
ib_post_send() does not disconnect the QP when it returns an
immediate error. Thus, the code that posts LocalInv has to
explicitly disconnect after an immediate error. This is just
like the frwr_send() callers handle it.
If a disconnect isn't done here, the transport deadlocks.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Highlights include:
Stable fixes:
- Two sunrpc fixes for deadlocks involving privileged rpc_wait_queues
Bugfixes
- SUNRPC: Avoid a KASAN slab-out-of-bounds bug in xdr_set_page_base()
- SUNRPC: prevent port reuse on transports which don't request it.
- NFSv3: Fix memory leak in posix_acl_create()
- NFS: Various fixes to attribute revalidation timeouts
- NFSv4: Fix handling of non-atomic change attribute updates
- NFSv4: If a server is down, don't cause mounts to other servers to
hang as well
- pNFS: Fix an Oops in pnfs_mark_request_commit() when doing O_DIRECT
- NFS: Fix mount failures due to incorrect setting of the has_sec_mnt_opts
filesystem flag
- NFS: Ensure nfs_readpage returns promptly when an internal error occurs
- NFS: Fix fscache read from NFS after cache error
- pNFS: Various bugfixes around the LAYOUTGET operation
Features
- Multiple patches to add support for fcntl() leases over NFSv4.
- A sysfs interface to display more information about the various
transport connections used by the RPC client
- A sysfs interface to allow a suitably privileged user to offline a
transport that may no longer point to a valid server
- A sysfs interface to allow a suitably privileged user to change the
server IP address used by the RPC client
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Merge tag 'nfs-for-5.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Features:
- Multiple patches to add support for fcntl() leases over NFSv4.
- A sysfs interface to display more information about the various
transport connections used by the RPC client
- A sysfs interface to allow a suitably privileged user to offline a
transport that may no longer point to a valid server
- A sysfs interface to allow a suitably privileged user to change the
server IP address used by the RPC client
Stable fixes:
- Two sunrpc fixes for deadlocks involving privileged rpc_wait_queues
Bugfixes:
- SUNRPC: Avoid a KASAN slab-out-of-bounds bug in xdr_set_page_base()
- SUNRPC: prevent port reuse on transports which don't request it.
- NFSv3: Fix memory leak in posix_acl_create()
- NFS: Various fixes to attribute revalidation timeouts
- NFSv4: Fix handling of non-atomic change attribute updates
- NFSv4: If a server is down, don't cause mounts to other servers to
hang as well
- pNFS: Fix an Oops in pnfs_mark_request_commit() when doing O_DIRECT
- NFS: Fix mount failures due to incorrect setting of the
has_sec_mnt_opts filesystem flag
- NFS: Ensure nfs_readpage returns promptly when an internal error
occurs
- NFS: Fix fscache read from NFS after cache error
- pNFS: Various bugfixes around the LAYOUTGET operation"
* tag 'nfs-for-5.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (46 commits)
NFSv4/pNFS: Return an error if _nfs4_pnfs_v3_ds_connect can't load NFSv3
NFSv4/pNFS: Don't call _nfs4_pnfs_v3_ds_connect multiple times
NFSv4/pnfs: Clean up layout get on open
NFSv4/pnfs: Fix layoutget behaviour after invalidation
NFSv4/pnfs: Fix the layout barrier update
NFS: Fix fscache read from NFS after cache error
NFS: Ensure nfs_readpage returns promptly when internal error occurs
sunrpc: remove an offlined xprt using sysfs
sunrpc: provide showing transport's state info in the sysfs directory
sunrpc: display xprt's queuelen of assigned tasks via sysfs
sunrpc: provide multipath info in the sysfs directory
NFSv4.1 identify and mark RPC tasks that can move between transports
sunrpc: provide transport info in the sysfs directory
SUNRPC: take a xprt offline using sysfs
sunrpc: add dst_attr attributes to the sysfs xprt directory
SUNRPC for TCP display xprt's source port in sysfs xprt_info
SUNRPC query transport's source port
SUNRPC display xprt's main value in sysfs's xprt_info
SUNRPC mark the first transport
sunrpc: add add sysfs directory per xprt under each xprt_switch
...
We need to keep track of the type for a given transport.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
- add tracepoints for callbacks and for client creation and
destruction
- cache the mounts used for server-to-server copies
- expose callback information in /proc/fs/nfsd/clients/*/info
- don't hold locks unnecessarily while waiting for commits
- update NLM to use xdr_stream, as we have for NFSv2/v3/v4
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Merge tag 'nfsd-5.14' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
- add tracepoints for callbacks and for client creation and destruction
- cache the mounts used for server-to-server copies
- expose callback information in /proc/fs/nfsd/clients/*/info
- don't hold locks unnecessarily while waiting for commits
- update NLM to use xdr_stream, as we have for NFSv2/v3/v4
* tag 'nfsd-5.14' of git://linux-nfs.org/~bfields/linux: (69 commits)
nfsd: fix NULL dereference in nfs3svc_encode_getaclres
NFSD: Prevent a possible oops in the nfs_dirent() tracepoint
nfsd: remove redundant assignment to pointer 'this'
nfsd: Reduce contention for the nfsd_file nf_rwsem
lockd: Update the NLMv4 SHARE results encoder to use struct xdr_stream
lockd: Update the NLMv4 nlm_res results encoder to use struct xdr_stream
lockd: Update the NLMv4 TEST results encoder to use struct xdr_stream
lockd: Update the NLMv4 void results encoder to use struct xdr_stream
lockd: Update the NLMv4 FREE_ALL arguments decoder to use struct xdr_stream
lockd: Update the NLMv4 SHARE arguments decoder to use struct xdr_stream
lockd: Update the NLMv4 SM_NOTIFY arguments decoder to use struct xdr_stream
lockd: Update the NLMv4 nlm_res arguments decoder to use struct xdr_stream
lockd: Update the NLMv4 UNLOCK arguments decoder to use struct xdr_stream
lockd: Update the NLMv4 CANCEL arguments decoder to use struct xdr_stream
lockd: Update the NLMv4 LOCK arguments decoder to use struct xdr_stream
lockd: Update the NLMv4 TEST arguments decoder to use struct xdr_stream
lockd: Update the NLMv4 void arguments decoder to use struct xdr_stream
lockd: Update the NLMv1 SHARE results encoder to use struct xdr_stream
lockd: Update the NLMv1 nlm_res results encoder to use struct xdr_stream
lockd: Update the NLMv1 TEST results encoder to use struct xdr_stream
...
Fix some spelling mistakes in comments:
succes ==> success
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Commit 9ed5af268e ("SUNRPC: Clean up the handling of page padding
in rpc_prepare_reply_pages()") [Dec 2020] affects RPC Replies that
have a data payload (i.e., Write chunks).
rpcrdma_prepare_readch(), as its name suggests, sets up Read chunks
which are data payloads within RPC Calls. Those payloads are
constructed by xdr_write_pages(), which continues to stuff the call
buffer's tail kvec with the payload's XDR roundup. Thus removing
the tail buffer logic in rpcrdma_prepare_readch() was the wrong
thing to do.
Fixes: 586a0787ce ("xprtrdma: Clean up rpcrdma_prepare_readch()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Ensure that we fix the XPRT_CONGESTED starvation issue for RDMA as well
as socket based transports.
Ensure we always initialise the request after waking up from the backlog
list.
Fixes: e877a88d1f ("SUNRPC in case of backlog, hand free slots directly to waiting task")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Highlights include:
Stable fixes:
- Add validation of the UDP retrans parameter to prevent shift out-of-bounds
- Don't discard pNFS layout segments that are marked for return
Bugfixes:
- Fix a NULL dereference crash in xprt_complete_bc_request() when the
NFSv4.1 server misbehaves.
- Fix the handling of NFS READDIR cookie verifiers
- Sundry fixes to ensure attribute revalidation works correctly when the
server does not return post-op attributes.
- nfs4_bitmask_adjust() must not change the server global bitmasks
- Fix major timeout handling in the RPC code.
- NFSv4.2 fallocate() fixes.
- Fix the NFSv4.2 SEEK_HOLE/SEEK_DATA end-of-file handling
- Copy offload attribute revalidation fixes
- Fix an incorrect filehandle size check in the pNFS flexfiles driver
- Fix several RDMA transport setup/teardown races
- Fix several RDMA queue wrapping issues
- Fix a misplaced memory read barrier in sunrpc's call_decode()
Features:
- Micro optimisation of the TCP transmission queue using TCP_CORK
- statx() performance improvements by further splitting up the tracking
of invalid cached file metadata.
- Support the NFSv4.2 "change_attr_type" attribute and use it to
optimise handling of change attribute updates.
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Merge tag 'nfs-for-5.13-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable fixes:
- Add validation of the UDP retrans parameter to prevent shift
out-of-bounds
- Don't discard pNFS layout segments that are marked for return
Bugfixes:
- Fix a NULL dereference crash in xprt_complete_bc_request() when the
NFSv4.1 server misbehaves.
- Fix the handling of NFS READDIR cookie verifiers
- Sundry fixes to ensure attribute revalidation works correctly when
the server does not return post-op attributes.
- nfs4_bitmask_adjust() must not change the server global bitmasks
- Fix major timeout handling in the RPC code.
- NFSv4.2 fallocate() fixes.
- Fix the NFSv4.2 SEEK_HOLE/SEEK_DATA end-of-file handling
- Copy offload attribute revalidation fixes
- Fix an incorrect filehandle size check in the pNFS flexfiles driver
- Fix several RDMA transport setup/teardown races
- Fix several RDMA queue wrapping issues
- Fix a misplaced memory read barrier in sunrpc's call_decode()
Features:
- Micro optimisation of the TCP transmission queue using TCP_CORK
- statx() performance improvements by further splitting up the
tracking of invalid cached file metadata.
- Support the NFSv4.2 'change_attr_type' attribute and use it to
optimise handling of change attribute updates"
* tag 'nfs-for-5.13-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (85 commits)
xprtrdma: Fix a NULL dereference in frwr_unmap_sync()
sunrpc: Fix misplaced barrier in call_decode
NFSv4.2: Remove ifdef CONFIG_NFSD from NFSv4.2 client SSC code.
xprtrdma: Move fr_mr field to struct rpcrdma_mr
xprtrdma: Move the Work Request union to struct rpcrdma_mr
xprtrdma: Move fr_linv_done field to struct rpcrdma_mr
xprtrdma: Move cqe to struct rpcrdma_mr
xprtrdma: Move fr_cid to struct rpcrdma_mr
xprtrdma: Remove the RPC/RDMA QP event handler
xprtrdma: Don't display r_xprt memory addresses in tracepoints
xprtrdma: Add an rpcrdma_mr_completion_class
xprtrdma: Add tracepoints showing FastReg WRs and remote invalidation
xprtrdma: Avoid Send Queue wrapping
xprtrdma: Do not wake RPC consumer on a failed LocalInv
xprtrdma: Do not recycle MR after FastReg/LocalInv flushes
xprtrdma: Clarify use of barrier in frwr_wc_localinv_done()
xprtrdma: Rename frwr_release_mr()
xprtrdma: rpcrdma_mr_pop() already does list_del_init()
xprtrdma: Delete rpcrdma_recv_buffer_put()
xprtrdma: Fix cwnd update ordering
...
The normal mechanism that invalidates and unmaps MRs is
frwr_unmap_async(). frwr_unmap_sync() is used only when an RPC
Reply bearing Write or Reply chunks has been lost (ie, almost
never).
Coverity found that after commit 9a301cafc8 ("xprtrdma: Move
fr_linv_done field to struct rpcrdma_mr"), the while() loop in
frwr_unmap_sync() exits only once @mr is NULL, unconditionally
causing subsequent dereferences of @mr to Oops.
I've tested this fix by creating a client that skips invoking
frwr_unmap_async() when RPC Replies complete. That forces all
invalidation tasks to fall upon frwr_unmap_sync(). Simple workloads
with this fix applied to the adulterated client work as designed.
Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1504556 ("Null pointer dereferences")
Fixes: 9a301cafc8 ("xprtrdma: Move fr_linv_done field to struct rpcrdma_mr")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up: The last remaining field in struct rpcrdma_frwr has been
removed, so the struct can be eliminated.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up: Move more of struct rpcrdma_frwr into its parent.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up.
- Simplify variable initialization in the completion handlers.
- Move another field out of struct rpcrdma_frwr.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up (for several purposes):
- The MR's cid is initialized sooner so that tracepoints can show
something reasonable even if the MR is never posted.
- The MR's res.id doesn't change so the cid won't change either.
Initializing the cid once is sufficient.
- struct rpcrdma_frwr is going away soon.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up: The handler only recorded a trace event. If indeed no
action is needed by the RPC/RDMA consumer, then the event can be
ignored.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The Send signaling logic is a little subtle, so add some
observability around it. For every xprtrdma_mr_fastreg event, there
should be an xprtrdma_mr_localinv or xprtrdma_mr_reminv event.
When these tracepoints are enabled, we can see exactly when an MR is
DMA-mapped, registered, invalidated (either locally or remotely) and
then DMA-unmapped.
kworker/u25:2-190 [000] 787.979512: xprtrdma_mr_map: task:351@5 mr.id=4 nents=2 5608@0x8679e0c8f6f56000:0x00000503 (TO_DEVICE)
kworker/u25:2-190 [000] 787.979515: xprtrdma_chunk_read: task:351@5 pos=148 5608@0x8679e0c8f6f56000:0x00000503 (last)
kworker/u25:2-190 [000] 787.979519: xprtrdma_marshal: task:351@5 xid=0x8679e0c8: hdr=52 xdr=148/5608/0 read list/inline
kworker/u25:2-190 [000] 787.979525: xprtrdma_mr_fastreg: task:351@5 mr.id=4 nents=2 5608@0x8679e0c8f6f56000:0x00000503 (TO_DEVICE)
kworker/u25:2-190 [000] 787.979526: xprtrdma_post_send: task:351@5 cq.id=0 cid=73 (2 SGEs)
...
kworker/5:1H-219 [005] 787.980567: xprtrdma_wc_receive: cq.id=1 cid=161 status=SUCCESS (0/0x0) received=164
kworker/5:1H-219 [005] 787.980571: xprtrdma_post_recvs: peer=[192.168.100.55]:20049 r_xprt=0xffff8884974d4000: 0 new recvs, 70 active (rc 0)
kworker/5:1H-219 [005] 787.980573: xprtrdma_reply: task:351@5 xid=0x8679e0c8 credits=64
kworker/5:1H-219 [005] 787.980576: xprtrdma_mr_reminv: task:351@5 mr.id=4 nents=2 5608@0x8679e0c8f6f56000:0x00000503 (TO_DEVICE)
kworker/5:1H-219 [005] 787.980577: xprtrdma_mr_unmap: mr.id=4 nents=2 5608@0x8679e0c8f6f56000:0x00000503 (TO_DEVICE)
Note that I've moved the xprtrdma_post_send tracepoint so that event
always appears after the xprtrdma_mr_fastreg tracepoint. Otherwise
the event log looks counterintuitive (FastReg is always supposed to
happen before Send).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Send WRs can be signalled or unsignalled. A signalled Send WR
always has a matching Send completion, while a unsignalled Send
has a completion only if the Send WR fails.
xprtrdma has a Send account mechanism that is designed to reduce
the number of signalled Send WRs. This in turn mitigates the
interrupt rate of the underlying device.
RDMA consumers can't leave all Sends unsignaled, however, because
providers rely on Send completions to maintain their Send Queue head
and tail pointers. xprtrdma counts the number of unsignaled Send WRs
that have been posted to ensure that Sends are signalled often
enough to prevent the Send Queue from wrapping.
This mechanism neglected to account for FastReg WRs, which are
posted on the Send Queue but never signalled. As a result, the
Send Queue wrapped on occasion, resulting in duplication completions
of FastReg and LocalInv WRs.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Throw away any reply where the LocalInv flushes or could not be
posted. The registered memory region is in an unknown state until
the disconnect completes.
rpcrdma_xprt_disconnect() will find and release the MR. No need to
put it back on the MR free list in this case.
The client retransmits pending RPC requests once it reestablishes a
fresh connection, so a replacement reply should be forthcoming on
the next connection instance.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Better not to touch MRs involved in a flush or post error until the
Send and Receive Queues are drained and the transport is fully
quiescent. Simply don't insert such MRs back onto the free list.
They remain on mr_all and will be released when the connection is
torn down.
I had thought that recycling would prevent hardware resources from
being tied up for a long time. However, since v5.7, a transport
disconnect destroys the QP and other hardware-owned resources. The
MRs get cleaned up nicely at that point.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up: The comment and the placement of the memory barrier is
confusing. Humans want to read the function statements from head
to tail.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up: To be consistent with other functions in this source file,
follow the naming convention of putting the object being acted upon
before the action itself.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The rpcrdma_mr_pop() earlier in the function has already cleared
out mr_list, so it must not be done again in the error path.
Fixes: 847568942f ("xprtrdma: Remove fr_state")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Linus Torvalds