tsh_size was added to accommodate transports that send a pre-amble
before each RPC message. However, this assumes the pre-amble is
fixed in size, which isn't true for some transports. That makes
tsh_size not very generic.
Also I'd like to make the estimation of RPC send and receive
buffer sizes more precise. tsh_size doesn't currently appear to be
accounted for at all by call_allocate.
Therefore let's just remove the tsh_size concept, and make the only
transports that have a non-zero tsh_size employ a direct approach.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Transport disconnect processing does a "wake pending tasks" at
various points.
Suppose an RPC Reply is being processed. The RPC task that Reply
goes with is waiting on the pending queue. If a disconnect wake-up
happens before reply processing is done, that reply, even if it is
good, is thrown away, and the RPC has to be sent again.
This window apparently does not exist for socket transports because
there is a lock held while a reply is being received which prevents
the wake-up call until after reply processing is done.
To resolve this, all RPC replies being processed on an RPC-over-RDMA
transport have to complete before pending tasks are awoken due to a
transport disconnect.
Callers that already hold the transport write lock may invoke
->ops->close directly. Others use a generic helper that schedules
a close when the write lock can be taken safely.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
already supported COPY, by copying a limited amount of data and then
returning a short result, letting the client resend. The asynchronous
protocol should offer better performance at the expense of some
complexity.
The other highlight is Trond's work to convert the duplicate reply cache
to a red-black tree, and to move it and some other server caches to RCU.
(Previously these have meant taking global spinlocks on every RPC.)
Otherwise, some RDMA work and miscellaneous bugfixes.
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Merge tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Olga added support for the NFSv4.2 asynchronous copy protocol. We
already supported COPY, by copying a limited amount of data and then
returning a short result, letting the client resend. The asynchronous
protocol should offer better performance at the expense of some
complexity.
The other highlight is Trond's work to convert the duplicate reply
cache to a red-black tree, and to move it and some other server caches
to RCU. (Previously these have meant taking global spinlocks on every
RPC)
Otherwise, some RDMA work and miscellaneous bugfixes"
* tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux: (30 commits)
lockd: fix access beyond unterminated strings in prints
nfsd: Fix an Oops in free_session()
nfsd: correctly decrement odstate refcount in error path
svcrdma: Increase the default connection credit limit
svcrdma: Remove try_module_get from backchannel
svcrdma: Remove ->release_rqst call in bc reply handler
svcrdma: Reduce max_send_sges
nfsd: fix fall-through annotations
knfsd: Improve lookup performance in the duplicate reply cache using an rbtree
knfsd: Further simplify the cache lookup
knfsd: Simplify NFS duplicate replay cache
knfsd: Remove dead code from nfsd_cache_lookup
SUNRPC: Simplify TCP receive code
SUNRPC: Replace the cache_detail->hash_lock with a regular spinlock
SUNRPC: Remove non-RCU protected lookup
NFS: Fix up a typo in nfs_dns_ent_put
NFS: Lockless DNS lookups
knfsd: Lockless lookup of NFSv4 identities.
SUNRPC: Lockless server RPCSEC_GSS context lookup
knfsd: Allow lockless lookups of the exports
...
Since commit ffe1f0df58 ("rpcrdma: Merge svcrdma and xprtrdma
modules into one"), the forward and backchannel components are part
of the same kernel module. A separate try_module_get() call in the
backchannel code is no longer necessary.
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>
Similar to a change made in the client's forward channel reply
handler: The xprt_release_rqst_cong() call is not necessary.
Also, release xprt->recv_lock when taking xprt->transport_lock
to avoid disabling and enabling BH's while holding another
spin lock.
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>
Stable bugfixes:
- Reset credit grant properly after a disconnect
Other bugfixes and cleanups:
- xprt_release_rqst_cong is called outside of transport_lock
- Create more MRs at a time and toss out old ones during recovery
- Various improvements to the RDMA connection and disconnection code:
- Improve naming of trace events, functions, and variables
- Add documenting comments
- Fix metrics and stats reporting
- Fix a tracepoint sparse warning
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Merge tag 'nfs-rdma-for-4.20-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
NFS RDMA client updates for Linux 4.20
Stable bugfixes:
- Reset credit grant properly after a disconnect
Other bugfixes and cleanups:
- xprt_release_rqst_cong is called outside of transport_lock
- Create more MRs at a time and toss out old ones during recovery
- Various improvements to the RDMA connection and disconnection code:
- Improve naming of trace events, functions, and variables
- Add documenting comments
- Fix metrics and stats reporting
- Fix a tracepoint sparse warning
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
On a fresh connection, an RPC/RDMA client is supposed to send only
one RPC Call until it gets a credit grant in the first RPC Reply
from the server [RFC 8166, Section 3.3.3].
There is a bug in the Linux client's credit accounting mechanism
introduced by commit e7ce710a88 ("xprtrdma: Avoid deadlock when
credit window is reset"). On connect, it simply dumps all pending
RPC Calls onto the new connection.
Servers have been tolerant of this bad behavior. Currently no server
implementation ever changes its credit grant over reconnects, and
servers always repost enough Receives before connections are fully
established.
To correct this issue, ensure that the client resets both the credit
grant _and_ the congestion window when handling a reconnect.
Fixes: e7ce710a88 ("xprtrdma: Avoid deadlock when credit ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Treat socket write space handling in the same way we now treat transport
congestion: by denying the XPRT_LOCK until the transport signals that it
has free buffer space.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we shift to using the transmit queue, then the task that holds the
write lock will not necessarily be the same as the one being transmitted.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Highlights include:
Stable fixes:
- Fix a 1-byte stack overflow in nfs_idmap_read_and_verify_message
- Fix a hang due to incorrect error returns in rpcrdma_convert_iovs()
- Revert an incorrect change to the NFSv4.1 callback channel
- Fix a bug in the NFSv4.1 sequence error handling
Features and optimisations:
- Support for piggybacking a LAYOUTGET operation to the OPEN compound
- RDMA performance enhancements to deal with transport congestion
- Add proper SPDX tags for NetApp-contributed RDMA source
- Do not request delegated file attributes (size+change) from the server
- Optimise away a GETATTR in the lookup revalidate code when doing NFSv4 OPEN
- Optimise away unnecessary lookups for rename targets
- Misc performance improvements when freeing NFSv4 delegations
Bugfixes and cleanups:
- Try to fail quickly if proto=rdma
- Clean up RDMA receive trace points
- Fix sillyrename to return the delegation when appropriate
- Misc attribute revalidation fixes
- Immediately clear the pNFS layout on a file when the server returns ESTALE
- Return NFS4ERR_DELAY when delegation/layout recalls fail due to igrab()
- Fix the client behaviour on NFS4ERR_SEQ_FALSE_RETRY
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Merge tag 'nfs-for-4.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable fixes:
- Fix a 1-byte stack overflow in nfs_idmap_read_and_verify_message
- Fix a hang due to incorrect error returns in rpcrdma_convert_iovs()
- Revert an incorrect change to the NFSv4.1 callback channel
- Fix a bug in the NFSv4.1 sequence error handling
Features and optimisations:
- Support for piggybacking a LAYOUTGET operation to the OPEN compound
- RDMA performance enhancements to deal with transport congestion
- Add proper SPDX tags for NetApp-contributed RDMA source
- Do not request delegated file attributes (size+change) from the
server
- Optimise away a GETATTR in the lookup revalidate code when doing
NFSv4 OPEN
- Optimise away unnecessary lookups for rename targets
- Misc performance improvements when freeing NFSv4 delegations
Bugfixes and cleanups:
- Try to fail quickly if proto=rdma
- Clean up RDMA receive trace points
- Fix sillyrename to return the delegation when appropriate
- Misc attribute revalidation fixes
- Immediately clear the pNFS layout on a file when the server returns
ESTALE
- Return NFS4ERR_DELAY when delegation/layout recalls fail due to
igrab()
- Fix the client behaviour on NFS4ERR_SEQ_FALSE_RETRY"
* tag 'nfs-for-4.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (80 commits)
skip LAYOUTRETURN if layout is invalid
NFSv4.1: Fix the client behaviour on NFS4ERR_SEQ_FALSE_RETRY
NFSv4: Fix a typo in nfs41_sequence_process
NFSv4: Revert commit 5f83d86cf5 ("NFSv4.x: Fix wraparound issues..")
NFSv4: Return NFS4ERR_DELAY when a layout recall fails due to igrab()
NFSv4: Return NFS4ERR_DELAY when a delegation recall fails due to igrab()
NFSv4.0: Remove transport protocol name from non-UCS client ID
NFSv4.0: Remove cl_ipaddr from non-UCS client ID
NFSv4: Fix a compiler warning when CONFIG_NFS_V4_1 is undefined
NFS: Filter cache invalidation when holding a delegation
NFS: Ignore NFS_INO_REVAL_FORCED in nfs_check_inode_attributes()
NFS: Improve caching while holding a delegation
NFS: Fix attribute revalidation
NFS: fix up nfs_setattr_update_inode
NFSv4: Ensure the inode is clean when we set a delegation
NFSv4: Ignore NFS_INO_REVAL_FORCED in nfs4_proc_access
NFSv4: Don't ask for delegated attributes when adding a hard link
NFSv4: Don't ask for delegated attributes when revalidating the inode
NFS: Pass the inode down to the getattr() callback
NFSv4: Don't request size+change attribute if they are delegated to us
...
While sending each RPC Reply, svc_rdma_sendto allocates and DMA-
maps a separate buffer where the RPC/RDMA transport header is
constructed. The buffer is unmapped and released in the Send
completion handler. This is significant per-RPC overhead,
especially for small RPCs.
Instead, allocate and DMA-map a buffer, and cache it in each
svc_rdma_send_ctxt. This buffer and its mapping can be re-used
for each RPC, saving the cost of memory allocation and DMA
mapping.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Now that the send_wr is part of the svc_rdma_send_ctxt,
svc_rdma_post_send_wr is nearly empty.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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>
Clean up: Since there's already a svc_rdma_op_ctxt being passed
around with the running count of mapped SGEs, drop unneeded
parameters to svc_rdma_post_send_wr().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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>
Refactor: xprtrdma needs to have better control over when RPCs are
awoken from the backlog queue, so replace xprt_free_slot with a
transport op callout.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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>
- fix a number of races in the NFSv4+ state code.
- fix some shutdown crashes in multiple-network-namespace cases.
- relax our 4.1 session limits; if you've an artificially low limit
to the number of 4.1 clients that can mount simultaneously, try
upgrading.
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Merge tag 'nfsd-4.15' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Lots of good bugfixes, including:
- fix a number of races in the NFSv4+ state code
- fix some shutdown crashes in multiple-network-namespace cases
- relax our 4.1 session limits; if you've an artificially low limit
to the number of 4.1 clients that can mount simultaneously, try
upgrading"
* tag 'nfsd-4.15' of git://linux-nfs.org/~bfields/linux: (22 commits)
SUNRPC: Improve ordering of transport processing
nfsd: deal with revoked delegations appropriately
svcrdma: Enqueue after setting XPT_CLOSE in completion handlers
nfsd: use nfs->ns.inum as net ID
rpc: remove some BUG()s
svcrdma: Preserve CB send buffer across retransmits
nfds: avoid gettimeofday for nfssvc_boot time
fs, nfsd: convert nfs4_file.fi_ref from atomic_t to refcount_t
fs, nfsd: convert nfs4_cntl_odstate.co_odcount from atomic_t to refcount_t
fs, nfsd: convert nfs4_stid.sc_count from atomic_t to refcount_t
lockd: double unregister of inetaddr notifiers
nfsd4: catch some false session retries
nfsd4: fix cached replies to solo SEQUENCE compounds
sunrcp: make function _svc_create_xprt static
SUNRPC: Fix tracepoint storage issues with svc_recv and svc_rqst_status
nfsd: use ARRAY_SIZE
nfsd: give out fewer session slots as limit approaches
nfsd: increase DRC cache limit
nfsd: remove unnecessary nofilehandle checks
nfs_common: convert int to bool
...
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This further reduces contention with the transport_lock, and allows us
to convert to using a non-bh-safe spinlock, since the list is now never
accessed from a bh context.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
After transport instance creation, these function pointers never
change. Mark them as constant to prevent their use as an attack
vector for code injections.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Replace C structure-based XDR decoding with pointer arithmetic.
Pointer arithmetic is considered more portable.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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>
Introduce a helper to DMA-map a reply's transport header before
sending it. This will in part replace the map vector cache.
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>
Clean up: Move the ib_send_wr off the stack, and move common code
to post a Send Work Request into a helper.
This is a refactoring change only.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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
...
Removing linux/phy.h from net/dsa.h reveals a build error in the sunrpc
code:
net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function 'xprt_rdma_bc_put':
net/sunrpc/xprtrdma/svc_rdma_backchannel.c:277:2: error: implicit declaration of function 'module_put' [-Werror=implicit-function-declaration]
net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function 'xprt_setup_rdma_bc':
net/sunrpc/xprtrdma/svc_rdma_backchannel.c:348:7: error: implicit declaration of function 'try_module_get' [-Werror=implicit-function-declaration]
Fix this by adding linux/module.h to svc_rdma_backchannel.c
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace C structure-based XDR decoding with pointer arithmetic.
Pointer arithmetic is considered more portable.
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>
Clean up.
/linux-2.6/net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function
‘xprt_rdma_bc_allocate’:
linux-2.6/net/sunrpc/xprtrdma/svc_rdma_backchannel.c:169:23: warning:
variable ‘rdma’ set but not used [-Wunused-but-set-variable]
struct svcxprt_rdma *rdma;
^
Fixes: 5d252f90a8 ("svcrdma: Add class for RDMA backwards ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Logic copied from xs_setup_bc_tcp().
Fixes: 39a9beab5a ('rpc: share one xps between all backchannels')
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The underlying transport releases the page pointed to by rq_buffer
during xprt_rdma_bc_send_request. When the backchannel reply arrives,
rq_rbuffer then points to freed memory.
Fixes: 68778945e4 ('SUNRPC: Separate buffer pointers for RPC ...')
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Highlights include:
Stable bugfixes:
- sunrpc: fix writ espace race causing stalls
- NFS: Fix inode corruption in nfs_prime_dcache()
- NFSv4: Don't report revoked delegations as valid in
nfs_have_delegation()
- NFSv4: nfs4_copy_delegation_stateid() must fail if the delegation is
invalid
- NFSv4: Open state recovery must account for file permission changes
- NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic
Features:
- Add support for tracking multiple layout types with an ordered list
- Add support for using multiple backchannel threads on the client
- Add support for pNFS file layout session trunking
- Delay xprtrdma use of DMA API (for device driver removal)
- Add support for xprtrdma remote invalidation
- Add support for larger xprtrdma inline thresholds
- Use a scatter/gather list for sending xprtrdma RPC calls
- Add support for the CB_NOTIFY_LOCK callback
- Improve hashing sunrpc auth_creds by using both uid and gid
Bugfixes:
- Fix xprtrdma use of DMA API
- Validate filenames before adding to the dcache
- Fix corruption of xdr->nwords in xdr_copy_to_scratch
- Fix setting buffer length in xdr_set_next_buffer()
- Don't deadlock the state manager on the SEQUENCE status flags
- Various delegation and stateid related fixes
- Retry operations if an interrupted slot receives EREMOTEIO
- Make nfs boot time y2038 safe
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Merge tag 'nfs-for-4.9-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"Highlights include:
Stable bugfixes:
- sunrpc: fix writ espace race causing stalls
- NFS: Fix inode corruption in nfs_prime_dcache()
- NFSv4: Don't report revoked delegations as valid in nfs_have_delegation()
- NFSv4: nfs4_copy_delegation_stateid() must fail if the delegation is invalid
- NFSv4: Open state recovery must account for file permission changes
- NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic
Features:
- Add support for tracking multiple layout types with an ordered list
- Add support for using multiple backchannel threads on the client
- Add support for pNFS file layout session trunking
- Delay xprtrdma use of DMA API (for device driver removal)
- Add support for xprtrdma remote invalidation
- Add support for larger xprtrdma inline thresholds
- Use a scatter/gather list for sending xprtrdma RPC calls
- Add support for the CB_NOTIFY_LOCK callback
- Improve hashing sunrpc auth_creds by using both uid and gid
Bugfixes:
- Fix xprtrdma use of DMA API
- Validate filenames before adding to the dcache
- Fix corruption of xdr->nwords in xdr_copy_to_scratch
- Fix setting buffer length in xdr_set_next_buffer()
- Don't deadlock the state manager on the SEQUENCE status flags
- Various delegation and stateid related fixes
- Retry operations if an interrupted slot receives EREMOTEIO
- Make nfs boot time y2038 safe"
* tag 'nfs-for-4.9-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (100 commits)
NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic
fs: nfs: Make nfs boot time y2038 safe
sunrpc: replace generic auth_cred hash with auth-specific function
sunrpc: add RPCSEC_GSS hash_cred() function
sunrpc: add auth_unix hash_cred() function
sunrpc: add generic_auth hash_cred() function
sunrpc: add hash_cred() function to rpc_authops struct
Retry operation on EREMOTEIO on an interrupted slot
pNFS: Fix atime updates on pNFS clients
sunrpc: queue work on system_power_efficient_wq
NFSv4.1: Even if the stateid is OK, we may need to recover the open modes
NFSv4: If recovery failed for a specific open stateid, then don't retry
NFSv4: Fix retry issues with nfs41_test/free_stateid
NFSv4: Open state recovery must account for file permission changes
NFSv4: Mark the lock and open stateids as invalid after freeing them
NFSv4: Don't test open_stateid unless it is set
NFSv4: nfs4_do_handle_exception() handle revoke/expiry of a single stateid
NFS: Always call nfs_inode_find_state_and_recover() when revoking a delegation
NFSv4: Fix a race when updating an open_stateid
NFSv4: Fix a race in nfs_inode_reclaim_delegation()
...
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>
xprtrdma needs to allocate the Call and Reply buffers separately.
TBH, the reliance on using a single buffer for the pair of XDR
buffers is transport implementation-specific.
Instead of passing just the rq_buffer into the buf_free method, pass
the task structure and let buf_free take care of freeing both
XDR buffers at once.
There's a micro-optimization here. In the common case, both
xprt_release and the transport's buf_free method were checking if
rq_buffer was NULL. Now the check is done only once per RPC.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
xprtrdma needs to allocate the Call and Reply buffers separately.
TBH, the reliance on using a single buffer for the pair of XDR
buffers is transport implementation-specific.
Transports that want to allocate separate Call and Reply buffers
will ignore the "size" argument anyway. Don't bother passing it.
The buf_alloc method can't return two pointers. Instead, make the
method's return value an error code, and set the rq_buffer pointer
in the method itself.
This gives call_allocate an opportunity to terminate an RPC instead
of looping forever when a permanent problem occurs. If a request is
just bogus, or the transport is in a state where it can't allocate
resources for any request, there needs to be a way to kill the RPC
right there and not loop.
This immediately fixes a rare problem in the backchannel send path,
which loops if the server happens to send a CB request whose
call+reply size is larger than a page (which it shouldn't do yet).
One more issue: looks like xprt_inject_disconnect was incorrectly
placed in the failure path in call_allocate. It needs to be in the
success path, as it is for other call-sites.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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>
Clean up: Most svc_rdma_post_recv() call sites close the transport
connection when a receive cannot be posted. Wrap that in a common
helper.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Tested-by: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The NFS server's XDR encoders adds an XDR pad for content in the
xdr_buf page list at the beginning of the xdr_buf's tail buffer.
On RDMA transports, Write chunks are sent separately and without an
XDR pad.
If a Write chunk is being sent, strip off the pad in the tail buffer
so that inline content following the Write chunk remains XDR-aligned
when it is sent to the client.
BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=294
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We now alwasy have a per-PD local_dma_lkey available. Make use of that
fact in svc_rdma and stop registering our own MR.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
To support the server-side of an NFSv4.1 backchannel on RDMA
connections, add a transport class that enables backward
direction messages on an existing forward channel connection.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Chuck Lever