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>
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>
Extra resources for handling backchannel requests have to be
pre-allocated when a transport instance is created. Set up
additional fields in svcxprt_rdma to track these resources.
The max_requests fields are elements of the RPC-over-RDMA
protocol, so they should be u32. To ensure that unsigned
arithmetic is used everywhere, some other fields in the
svcxprt_rdma struct are updated.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
svc_rdma_post_recv() allocates pages for receive buffers on-demand.
It uses GFP_KERNEL so the allocator tries hard, and may sleep. But
I'm about to add a call to svc_rdma_post_recv() from a function
that may not sleep.
Since all svc_rdma_post_recv() call sites can tolerate its failure,
allow it to fail if the page allocator returns nothing. Longer term,
receive buffers, being a finite resource per-connection, should be
pre-allocated and re-used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
To ensure this allocation cannot fail and will not sleep,
pre-allocate the req_map structures per-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>
When the maximum payload size of NFS READ and WRITE was increased
by commit cc9a903d91 ("svcrdma: Change maximum server payload back
to RPCSVC_MAXPAYLOAD"), the size of struct svc_rdma_op_ctxt
increased to over 6KB (on x86_64). That makes allocating one of
these from a kmem_cache more likely to fail in situations when
system memory is exhausted.
Since I'm about to add a caller where this allocation must always
work _and_ it cannot sleep, pre-allocate ctxts for each connection.
Another motivation for this change is that NFSv4.x servers are
required by specification not to drop NFS requests. Pre-allocating
memory resources reduces the likelihood of a drop.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Pull NFS client updates from Trond Myklebust:
"Highlights include:
New features:
- RDMA client backchannel from Chuck
- Support for NFSv4.2 file CLONE using the btrfs ioctl
Bugfixes + cleanups:
- Move socket data receive out of the bottom halves and into a
workqueue
- Refactor NFSv4 error handling so synchronous and asynchronous RPC
handles errors identically.
- Fix a panic when blocks or object layouts reads return a bad data
length
- Fix nfsroot so it can handle a 1024 byte long path.
- Fix bad usage of page offset in bl_read_pagelist
- Various NFSv4 callback cleanups+fixes
- Fix GETATTR bitmap verification
- Support hexadecimal number for sunrpc debug sysctl files"
* tag 'nfs-for-4.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (53 commits)
Sunrpc: Supports hexadecimal number for sysctl files of sunrpc debug
nfs: Fix GETATTR bitmap verification
nfs: Remove unused xdr page offsets in getacl/setacl arguments
fs/nfs: remove unnecessary new_valid_dev check
SUNRPC: fix variable type
NFS: Enable client side NFSv4.1 backchannel to use other transports
pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS
pNFS/flexfiles: When mirrored, retry failed reads by switching mirrors
SUNRPC: Remove the TCP-only restriction in bc_svc_process()
svcrdma: Add backward direction service for RPC/RDMA transport
xprtrdma: Handle incoming backward direction RPC calls
xprtrdma: Add support for sending backward direction RPC replies
xprtrdma: Pre-allocate Work Requests for backchannel
xprtrdma: Pre-allocate backward rpc_rqst and send/receive buffers
SUNRPC: Abstract backchannel operations
xprtrdma: Saving IRQs no longer needed for rb_lock
xprtrdma: Remove reply tasklet
xprtrdma: Use workqueue to process RPC/RDMA replies
xprtrdma: Replace send and receive arrays
xprtrdma: Refactor reply handler error handling
...
Pull inifiniband/rdma updates from Doug Ledford:
"This is a fairly sizeable set of changes. I've put them through a
decent amount of testing prior to sending the pull request due to
that.
There are still a few fixups that I know are coming, but I wanted to
go ahead and get the big, sizable chunk into your hands sooner rather
than waiting for those last few fixups.
Of note is the fact that this creates what is intended to be a
temporary area in the drivers/staging tree specifically for some
cleanups and additions that are coming for the RDMA stack. We
deprecated two drivers (ipath and amso1100) and are waiting to hear
back if we can deprecate another one (ehca). We also put Intel's new
hfi1 driver into this area because it needs to be refactored and a
transfer library created out of the factored out code, and then it and
the qib driver and the soft-roce driver should all be modified to use
that library.
I expect drivers/staging/rdma to be around for three or four kernel
releases and then to go away as all of the work is completed and final
deletions of deprecated drivers are done.
Summary of changes for 4.3:
- Create drivers/staging/rdma
- Move amso1100 driver to staging/rdma and schedule for deletion
- Move ipath driver to staging/rdma and schedule for deletion
- Add hfi1 driver to staging/rdma and set TODO for move to regular
tree
- Initial support for namespaces to be used on RDMA devices
- Add RoCE GID table handling to the RDMA core caching code
- Infrastructure to support handling of devices with differing read
and write scatter gather capabilities
- Various iSER updates
- Kill off unsafe usage of global mr registrations
- Update SRP driver
- Misc mlx4 driver updates
- Support for the mr_alloc verb
- Support for a netlink interface between kernel and user space cache
daemon to speed path record queries and route resolution
- Ininitial support for safe hot removal of verbs devices"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (136 commits)
IB/ipoib: Suppress warning for send only join failures
IB/ipoib: Clean up send-only multicast joins
IB/srp: Fix possible protection fault
IB/core: Move SM class defines from ib_mad.h to ib_smi.h
IB/core: Remove unnecessary defines from ib_mad.h
IB/hfi1: Add PSM2 user space header to header_install
IB/hfi1: Add CSRs for CONFIG_SDMA_VERBOSITY
mlx5: Fix incorrect wc pkey_index assignment for GSI messages
IB/mlx5: avoid destroying a NULL mr in reg_user_mr error flow
IB/uverbs: reject invalid or unknown opcodes
IB/cxgb4: Fix if statement in pick_local_ip6adddrs
IB/sa: Fix rdma netlink message flags
IB/ucma: HW Device hot-removal support
IB/mlx4_ib: Disassociate support
IB/uverbs: Enable device removal when there are active user space applications
IB/uverbs: Explicitly pass ib_dev to uverbs commands
IB/uverbs: Fix race between ib_uverbs_open and remove_one
IB/uverbs: Fix reference counting usage of event files
IB/core: Make ib_dealloc_pd return void
IB/srp: Create an insecure all physical rkey only if needed
...
Both commit 0380a3f375 ("svcrdma: Add a separate "max data segs"
macro for svcrdma") and commit 7e5be28827 ("svcrdma: advertise
the correct max payload") are incorrect. This commit reverts both
changes, restoring the server's maximum payload size to 1MB.
Commit 7e5be28827 based the server's maximum payload on the
_client's_ RPCRDMA_MAX_DATA_SEGS value. That was wrong.
Commit 0380a3f375 tried to fix this so that the client maximum
payload size could be raised without affecting the server, but
managed to confuse matters more on the server side.
More importantly, limiting the advertised maximum payload size was
meant to be a workaround, not the actual fix. We need to revisit
https://bugzilla.linux-nfs.org/show_bug.cgi?id=270
A Linux client on a platform with 64KB pages can overrun and crash
an x86_64 NFS/RDMA server when the r/wsize is 1MB. An x86/64 Linux
client seems to work fine using 1MB reads and writes when the Linux
server's maximum payload size is restored to 1MB.
BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=270
Fixes: 0380a3f375 ("svcrdma: Add a separate "max data segs" macro")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Commit 0bf4828983 ("svcrdma: refactor marshalling logic") removed
the last call site for svc_rdma_fastreg().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Kernel coding conventions frown upon having large nontrivial
functions in header files, and the preference these days is to
allow the compiler to make inlining decisions if possible.
As these functions are re-homed into a .c file, be sure that
comparisons with fields in struct rpcrdma_msg are with be32
constants.
This is a refactoring change; no behavior change is intended.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The server and client maximum are architecturally independent.
Allow changing one without affecting the other.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
At the 2015 LSF/MM, it was requested that memory allocation
call sites that request GFP_KERNEL allocations in a loop should be
annotated with __GFP_NOFAIL.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Fields in struct rpcrdma_msg are __be32. Don't byte-swap these
fields when decoding RPC calls and then swap them back for the
reply. For the most part, they can be left alone.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
svc_rdma_xdr_decode_deferred_req() indexes an array with an
un-byte-swapped value off the wire. Fortunately this function
isn't used anywhere, so simply remove it.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Pull nfsd updates from Bruce Fields:
"The main change is the pNFS block server support from Christoph, which
allows an NFS client connected to shared disk to do block IO to the
shared disk in place of NFS reads and writes. This also requires xfs
patches, which should arrive soon through the xfs tree, barring
unexpected problems. Support for other filesystems is also possible
if there's interest.
Thanks also to Chuck Lever for continuing work to get NFS/RDMA into
shape"
* 'for-3.20' of git://linux-nfs.org/~bfields/linux: (32 commits)
nfsd: default NFSv4.2 to on
nfsd: pNFS block layout driver
exportfs: add methods for block layout exports
nfsd: add trace events
nfsd: update documentation for pNFS support
nfsd: implement pNFS layout recalls
nfsd: implement pNFS operations
nfsd: make find_any_file available outside nfs4state.c
nfsd: make find/get/put file available outside nfs4state.c
nfsd: make lookup/alloc/unhash_stid available outside nfs4state.c
nfsd: add fh_fsid_match helper
nfsd: move nfsd_fh_match to nfsfh.h
fs: add FL_LAYOUT lease type
fs: track fl_owner for leases
nfs: add LAYOUT_TYPE_MAX enum value
nfsd: factor out a helper to decode nfstime4 values
sunrpc/lockd: fix references to the BKL
nfsd: fix year-2038 nfs4 state problem
svcrdma: Handle additional inline content
svcrdma: Move read list XDR round-up logic
...
Currently the Linux server can not decode RDMA_NOMSG type requests.
Operations whose length exceeds the fixed size of RDMA SEND buffers,
like large NFSv4 CREATE(NF4LNK) operations, must be conveyed via
RDMA_NOMSG.
For an RDMA_MSG type request, the client sends the RPC/RDMA, RPC
headers, and some or all of the NFS arguments via RDMA SEND.
For an RDMA_NOMSG type request, the client sends just the RPC/RDMA
header via RDMA SEND. The request's read list contains elements for
the entire RPC message, including the RPC header.
NFSD expects the RPC/RMDA header and RPC header to be contiguous in
page zero of the XDR buffer. Add logic in the RDMA READ path to make
the read list contents land where the server prefers, when the
incoming message is a type RDMA_NOMSG message.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Chuck Lever
Christoph Hellwig
Linus Torvalds
Sagi Grimberg
Steve Wise