Also, a minor comment grammar fix in the same file.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The cl_chatty flag alows us to control whether a given rpc client leaves
"server X not responding, timed out"
messages in the syslog. Such messages make sense for ordinary nfs
clients (where an unresponsive server means applications on the
mountpoint are probably hanging), but not for the callback client (which
can fail more commonly, with the only result just of disabling some
optimizations).
Previously cl_chatty was removed, do to lack of users; reinstate it, and
use it for the nfsd's callback client.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Recent changes to the RPC client's transport connect logic make connect
status values ECONNREFUSED and ECONNRESET impossible.
Clean up xprt_connect_status() to account for these changes.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: move the logic that displays each task to its own function.
This removes indentation and makes future changes easier.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: don't display the rpc_show_tasks column header unless there is at
least one task to display. As far as I can tell, it is safe to let the
list_for_each_entry macro decide that each list is empty.
scripts/checkpatch.pl also wants a KERN_FOO at the start of any newly added
printk() calls, so this and subsequent patches will also add KERN_INFO.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The RPC client uses a finite state machine to move RPC tasks through each
step of an RPC request. Each state is contained in a function in
net/sunrpc/clnt.c, and named call_foo.
Some of the functions named call_foo have changed over the past few years and
are no longer states in the FSM. These include: call_encode, call_header,
and call_verify. As a clean up, rename the functions that have changed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Improve debugging messages in call_start() and call_verify() by having
them show the RPC procedure name instead of the procedure number.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Since the credentials may be allocated during the call to rpc_new_task(),
which again may be called by a memory allocator...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The special 'ENOMEM' case that was previously flagged as non-fatal is
bogus: auth_gss always returns EAGAIN for non-fatal errors, and may in fact
return ENOMEM in the special case where xdr_buf_read_netobj runs out of
preallocated buffer space (invariably a _fatal_ error, since there is no
provision for preallocating larger buffers).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
All errors from call_encode(), with exception of EAGAIN are fatal, so we
should immediately return instead of proceeding to xprt_transmit().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Now that rpcb_next_version has been split into an IPv4 version and an IPv6
version, we Oops when rpcb_call_async attempts to look up the IPv6-specific
RPC procedure in rpcb_next_version.
Fix the Oops simply by having rpcb_getport_async pass the correct RPC
procedure as an argument.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is wrong to be freeing up the rpcbind arguments if the call to
rpcb_call_async() fails, since they should already have been freed up by
rpcb_map_release().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
To return garbage_args, the accept_stat must be 0, and we must have a
verifier. So we shouldn't be resetting the write pointer as we reject
the call.
Also, we must add the two placeholder words here regardless of success
of the unwrap, to ensure the output buffer is left in a consistent state
for svcauth_gss_release().
This fixes a BUG() in svcauth_gss.c:svcauth_gss_release().
Thanks to Aime Le Rouzic for bug report, debugging help, and testing.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Tested-by: Aime Le Rouzic <aime.le-rouzic@bull.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the WR context pool to be shared across mount points. This
reduces the RDMA transport memory footprint significantly since
idle mounts don't consume WR context memory.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Create a kmem cache to hold WR contexts. Next we will convert
the WR context get and put services to use this kmem cache.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
When adapters have differing IRD limits, the RDMA transport will fail to
connect properly. The RDMA transport should use the client's advertised
inbound read limit when computing its outbound read limit. For iWARP
transports, there is currently no standard for exchanging IRD/ORD
during connection establishment so the 'responder_resources' field in the
connect event is the local device's limit. The RDMA transport can be
configured to use a smaller ORD by writing the desired number to the
/proc/sys/sunrpc/svc_rdma/max_outbound_read_requests file.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
At the time __svc_rdma_free is called, we are guaranteed that all references
to this transport are gone. There is, therefore, no need to protect the
resource lists with a spin lock.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Add a dma map count in order to verify that all DMA mapping resources
have been freed when the transport is closed.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Separate DMA unmap from context destruction and perform DMA unmapping
in the SQ/RQ CQ reap functions. This is necessary to support software
based RDMA implementations that actually copy the data in their
ib_dma_unmap callback functions and architectures that don't have
cache coherent I/O busses.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Modify the RDMA_READ processing to use the reply and chunk list mapping data
types. Also add a special purpose 'hdr_count' field in in the context to hold
the header page count instead of overloading the SGE length field and
corrupting the DMA map length.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Use the new svc_rdma_req_map data type for mapping the client side memory
to the server side memory. Move the DMA mapping to the context pointed to
by each WR individually so that it is unmapped after the WR completes.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Create a new data structure to hold the remote client address space
to local server address space mapping.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Initialize the value used for the confounder to a random value
rather than starting from zero.
Allow for confounders of length 8 or 16 (which will be needed for AES).
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The gss_krb5_crypto.o object belongs in the rpcsec_gss_krb5 module.
Also, there is no need to export symbols from gss_krb5_crypto.c
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
cleanup:
Document token header size with a #define instead of open-coding it.
Don't needlessly increment "ptr" past the beginning of the header
which makes the values passed to functions more understandable and
eliminates the need for extra "krb5_hdr" pointer.
Clean up some intersecting white-space issues flagged by checkpatch.pl.
This leaves the checksum length hard-coded at 8 for DES. A later patch
cleans that up.
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Since we no longer make any distinction between shutdown signals with
nfsd, then it becomes easier to just standardize on a particular signal
to use to bring it down (SIGINT, in this case).
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This patch is rather large, but I couldn't figure out a way to break it
up that would remain bisectable. It does several things:
- change svc_thread_fn typedef to better match what kthread_create expects
- change svc_pool_map_set_cpumask to be more kthread friendly. Make it
take a task arg and and get rid of the "oldmask"
- have svc_set_num_threads call kthread_create directly
- eliminate __svc_create_thread
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This removes the BKL from the RPC service creation codepath. The BKL
really isn't adequate for this job since some of this info needs
protection across sleeps.
Also, add some comments to try and clarify how the locking should work
and to make it clear that the BKL isn't necessary as long as there is
adequate locking between tasks when touching the svc_serv fields.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This patch removes CVS keywords that weren't updated for a long time
from comments.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* Pass reference to cpumask variable instead of using stack.
For inclusion into sched-devel/latest tree.
Based on:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
+ sched-devel/latest .../mingo/linux-2.6-sched-devel.git
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* 'for-2.6.26' of git://linux-nfs.org/~bfields/linux: (25 commits)
svcrdma: Verify read-list fits within RPCSVC_MAXPAGES
svcrdma: Change svc_rdma_send_error return type to void
svcrdma: Copy transport address and arm CQ before calling rdma_accept
svcrdma: Set rqstp transport address in rdma_read_complete function
svcrdma: Use ib verbs version of dma_unmap
svcrdma: Cleanup queued, but unprocessed I/O in svc_rdma_free
svcrdma: Move the QP and cm_id destruction to svc_rdma_free
svcrdma: Add reference for each SQ/RQ WR
svcrdma: Move destroy to kernel thread
svcrdma: Shrink scope of spinlock on RQ CQ
svcrdma: Use standard Linux lists for context cache
svcrdma: Simplify RDMA_READ deferral buffer management
svcrdma: Remove unused READ_DONE context flags bit
svcrdma: Return error from rdma_read_xdr so caller knows to free context
svcrdma: Fix error handling during listening endpoint creation
svcrdma: Free context on post_recv error in send_reply
svcrdma: Free context on ib_post_recv error
svcrdma: Add put of connection ESTABLISHED reference in rdma_cma_handler
svcrdma: Fix return value in svc_rdma_send
svcrdma: Fix race with dto_tasklet in svc_rdma_send
...
A RDMA read-list cannot contain more elements than RPCSVC_MAXPAGES or
it will overflow the DTO context. Verify this when processing the
protocol header.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
The svc_rdma_send_error function is called when an RPCRDMA protocol
error is detected. This function attempts to post an error reply message.
Since an error posting to a transport in error is ignored, change
the return type to void.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
This race was found by inspection. Messages can be received from the peer
immediately following the rdma_accept call, however, the CQ have not yet
been armed and the transport address has not yet been set.
Set the transport address in the connect request handler and arm the CQ
prior to calling rdma_accept.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
The rdma_read_complete function needs to copy the rqstp transport address
from the transport. Failure to do so can result in using the wrong
authentication method for the RPC or bug checking if the rqstp address
is not valid.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Use the ib_verbs version of the dma_unmap service in the
svc_rdma_put_context function. This should support providers
using software rdma.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
When the transport is closing, the DTO tasklet may queue data
that never gets processed. Clean up resources associated with
this I/O.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Move the destruction of the QP and CM_ID to the free path so that the
QP cleanup code doesn't race with the dto_tasklet handling flushed WR.
The QP reference is not needed because we now have a reference for
every WR.
Also add a guard in the SQ and RQ completion handlers to ignore
calls generated by some providers when the QP is destroyed.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Some providers may wait while destroying adapter resources.
Since it is possible that the last reference is put on the
dto_tasklet, the actual destroy must be scheduled as a work item.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
The rq_cq_reap function is only called from the dto_tasklet. The
only resource shared with other threads is the sc_rq_dto_q. Move the
spin lock to protect only this list.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Replace the one-off linked list implementation used to implement the
context cache with the standard Linux list_head lists. Add a context
counter to catch resource leaks. A WARN_ON will be added later to
ensure that we've freed all contexts.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
An NFS_WRITE requires a set of RDMA_READ requests to fetch the write
data from the client. There are two principal pieces of data that
need to be tracked: the list of pages that comprise the completed RPC
and the SGE of dma mapped pages to refer to this list of pages. Previously
this whole bit was managed as a linked list of contexts with the
context containing the page list buried in this list. This patch
simplifies this processing by not keeping a linked list, but rather only
a pionter from the last submitted RDMA_READ's context to the context
that maps the set of pages that describe the RPC. This significantly
simplifies this code path. SGE contexts are cleaned up inline in the DTO
path instead of at read completion time.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
The rdma_read_xdr function did not discriminate between no read-list and
an error posting the read-list. This results in a leak of a page if there
is an error posting the read-list.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
A listening endpoint isn't known to the generic transport switch until
the svc_create_xprt function returns without error. Calling
svc_xprt_put within the xpo_create function causes the module reference
count to be erroneously decremented.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
If an error is encountered trying to post a recv buffer in send_reply,
free the passed in context. Return an error to the caller so it is
aware that the request was not posted.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
If there is an error posting the recv WR to the RQ, free the
context associated with the WR. This would leak a context when
asynchronous errors occurred on the transport while conccurent threads
were processing their RPC.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
The svcrdma transport takes a reference when it gets the ESTABLISHED
event from the provider. This reference is supposed to be removed when
the DISCONNECT event is received, however, the call to svc_xprt_put
was missing in the switch statement. This results in the memory
associated with the transport never being freed.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Fix the return value on close to -ENOTCONN so caller knows to free context.
Also if a thread is waiting for free SQ space, check for close when waking
to avoid posting WR to a closing transport.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
The svc_rdma_send function will attempt to reap SQ WR to make room for
a new request if it finds the SQ full. This function races with the
dto_tasklet that also reaps SQ WR. To avoid polling and arming the CQ
unnecessarily move the test_and_clear_bit of the RDMAXPRT_SQ_PENDING
flag and arming of the CQ to the sq_cq_reap function.
Refactor the rq_cq_reap function to match sq_cq_reap so that the
code is easier to follow.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
The svcrdma transport provider currently allocates receive buffers
to the RQ through the xpo_release_rqst method. This approach is overly
complicated since it means that the rqstp rq_xprt_ctxt has to be
selectively set based on whether the RPC is going to be processed
immediately or deferred. Instead, just post the receive buffer when
we are certain that we are replying in the send_reply function.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Remove a redundant check for the XPT_DEAD bit in the svc_xprt_enqueue
function. This same bit is checked below while holding the pool lock
and prints a debug message if found to be dead.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Commit f15364bd4c ("IPv6 support for NFS
server export caches") dropped a couple spaces, rendering the output
here difficult to read.
(However note that we expect the output to be parsed only by humans, not
machines, so this shouldn't have broken any userland software.)
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Apparently this causes Solaris 10 servers to refuse our NFSv4 SETCLIENTID
calls. Fall back to root creds for now, since most servers that care are
very likely to have root squashing enabled.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Simply replace proc_create and further data assigned with proc_create_data.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
iwlwifi: Allow building iwl3945 without iwl4965.
wireless: Fix compile error with wifi & leds
tcp: Fix slab corruption with ipv6 and tcp6fuzz
ipv4/ipv6 compat: Fix SSM applications on 64bit kernels.
[IPSEC]: Use digest_null directly for auth
sunrpc: fix missing kernel-doc
can: Fix copy_from_user() results interpretation
Revert "ipv6: Fix typo in net/ipv6/Kconfig"
tipc: endianness annotations
ipv6: result of csum_fold() is already 16bit, no need to cast
[XFRM] AUDIT: Fix flowlabel text format ambibuity.
Fix missing sunrpc kernel-doc:
Warning(linux-2.6.25-git7//net/sunrpc/xprt.c:451): No description found for parameter 'action'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (80 commits)
SUNRPC: Invalidate the RPCSEC_GSS session if the server dropped the request
make nfs_automount_list static
NFS: remove duplicate flags assignment from nfs_validate_mount_data
NFS - fix potential NULL pointer dereference v2
SUNRPC: Don't change the RPCSEC_GSS context on a credential that is in use
SUNRPC: Fix a race in gss_refresh_upcall()
SUNRPC: Don't disconnect more than once if retransmitting NFSv4 requests
SUNRPC: Remove the unused export of xprt_force_disconnect
SUNRPC: remove XS_SENDMSG_RETRY
SUNRPC: Protect creds against early garbage collection
NFSv4: Attempt to use machine credentials in SETCLIENTID calls
NFSv4: Reintroduce machine creds
NFSv4: Don't use cred->cr_ops->cr_name in nfs4_proc_setclientid()
nfs: fix printout of multiword bitfields
nfs: return negative error value from nfs{,4}_stat_to_errno
NLM/lockd: Ensure client locking calls use correct credentials
NFS: Remove the buggy lock-if-signalled case from do_setlk()
NLM/lockd: Fix a race when cancelling a blocking lock
NLM/lockd: Ensure that nlmclnt_cancel() returns results of the CANCEL call
NLM: Remove the signal masking in nlmclnt_proc/nlmclnt_cancel
...
RFC 2203 requires the server to drop the request if it believes the
RPCSEC_GSS context is out of sequence. The problem is that we have no way
on the client to know why the server dropped the request. In order to avoid
spinning forever trying to resend the request, the safe approach is
therefore to always invalidate the RPCSEC_GSS context on every major
timeout.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Suppress a harmless compiler warning.
Index rq_pages[] with an unsigned type. Make "pages" unsigned as well,
as it never represents a value less than zero.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Suppress a harmless compiler warning in the RPC server related
to array indices.
ARRAY_SIZE() returns a size_t, so use unsigned type for a loop index when
looping over arrays.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Update the RPC server's TCP record marker decoder to match the
constructs used by the RPC client's TCP socket transport.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Use the 2.6 method for disabling TCP Nagle in the kernel's RPC server.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that the nfs4 callback thread uses the kthread API, there are no
more users of svc_create_thread(). Remove it.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
g_make_token_header() and g_token_size() add two too many, and
therefore their callers pass in "(logical_value - 2)" rather
than "logical_value" as hard-coded values which causes confusion.
This dates back to the original g_make_token_header which took an
optional token type (token_id) value and added it to the token.
This was removed, but the routine always adds room for the token_id
rather than not.
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Consistently use unsigned (u32 vs. s32) for seqnum.
In get_mic function, send the local copy of seq_send,
rather than the context version.
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
net/sunrpc/svc.c: In function '__svc_create_thread':
net/sunrpc/svc.c:587: warning: 'oldmask.bits[0u]' may be used uninitialized in this function
Cc: Neil Brown <neilb@suse.de>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Tom Tucker <tom@opengridcomputing.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
cleanup: When adding new encryption types, the checksum length
can be different for each enctype. Face the fact that the
current code only supports DES which has a checksum length of 8.
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
cleanup: Fix grammer/typos to use "too" instead of "to"
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
SVCRDMA: Add check for XPT_CLOSE in svc_rdma_send
The svcrdma transport can crash if a send is waiting for an
empty SQ slot and the connection is closed due to an asynchronous error.
The crash is caused when svc_rdma_send attempts to send on a deleted
QP.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
In function svcauth_gss_accept() (net/sunrpc/auth_gss/svcauth_gss.c) the
code that handles GSS integrity and decryption failures should be
returning GARBAGE_ARGS as specified in RFC 2203, sections 5.3.3.4.2 and
5.3.3.4.3.
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: Harshula Jayasuriya <harshula@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
svc_recv() calls alloc_page(), and if it fails it does a 500ms
uninterruptible sleep and then reattempts. There doesn't seem to be any
real reason for this to be uninterruptible, so change it to an
interruptible sleep. Also check for kthread_stop() and signalled() after
setting the task state to avoid races that might lead to sleeping after
kthread_stop() wakes up the task.
I've done some very basic smoke testing with this, but obviously it's
hard to test the actual changes since this all depends on an
alloc_page() call failing.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This field is set once and never used; probably some artifact of an
earlier implementation idea.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This adds IPv6 support to the interfaces that are used to express nfsd
exports. All addressed are stored internally as IPv6; backwards
compatibility is maintained using mapped addresses.
Thanks to Bruce Fields, Brian Haley, Neil Brown and Hideaki Joshifuji
for comments
Signed-off-by: Aurelien Charbon <aurelien.charbon@bull.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Brian Haley <brian.haley@hp.com>
Cc: YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@linux-ipv6.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
When using kthreads that call into svc_recv, we want to make sure that
they do not block there for a long time when we're trying to take down
the kthread.
This patch changes svc_recv() to check kthread_should_stop() at the same
places that it checks to see if it's signalled(). Also check just before
svc_recv() tries to schedule(). By making sure that we check it just
after setting the task state we can avoid having to use any locking or
signalling to ensure it doesn't block for a long time.
There's still a chance of a 500ms sleep if alloc_page() fails, but
that should be a rare occurrence and isn't a terribly long time in
the context of a kthread being taken down.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Needed since the plan is to not have a svc_create_thread helper and to
have current users of that function just call kthread_run directly.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
When a server rejects our credential with an AUTH_REJECTEDCRED or similar,
we need to refresh the credential and then retry the request.
However, we do want to allow any requests that are in flight to finish
executing, so that we can at least attempt to process the replies that
depend on this instance of the credential.
The solution is to ensure that gss_refresh() looks up an entirely new
RPCSEC_GSS credential instead of attempting to create a context for the
existing invalid credential.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the downcall completes before we get the spin_lock then we currently
fail to refresh the credential.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv4 requires us to ensure that we break the TCP connection before we're
allowed to retransmit a request. However in the case where we're
retransmitting several requests that have been sent on the same
connection, we need to ensure that we don't interfere with the attempt to
reconnect and/or break the connection again once it has been established.
We therefore introduce a 'connection' cookie that is bumped every time a
connection is broken. This allows requests to track if they need to force a
disconnection.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The condition for exiting from the loop in xs_tcp_send_request() should be
that we find we're not making progress (i.e. number of bytes sent is 0).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We need to try to ensure that we always use the same credentials whenever
we re-establish the clientid on the server. If not, the server won't
recognise that we're the same client, and so may not allow us to recover
state.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
With the recent change to generic creds, we can no longer use
cred->cr_ops->cr_name to distinguish between RPCSEC_GSS principals and
AUTH_SYS/AUTH_NULL identities. Replace it with the rpc_authops->au_name
instead...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to ensure that req->rq_private_buf.len is updated before
req->rq_received, so that call_decode() doesn't use an old value for
req->rq_rcv_buf.len.
In 'call_decode()' itself, instead of using task->tk_status (which is set
using req->rq_received) must use the actual value of
req->rq_private_buf.len when deciding whether or not the received RPC reply
is too short.
Finally ensure that we set req->rq_rcv_buf.len to zero when retrying a
request. A typo meant that we were resetting req->rq_private_buf.len in
call_decode(), and then clobbering that value with the old rq_rcv_buf.len
again in xprt_transmit().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
..and always destroy using a 'soft' RPC call. Destroying GSS credentials
isn't mandatory; the server can always cope with a few credentials not
getting destroyed in a timely fashion.
This actually fixes a hang situation. Basically, some servers will decide
that the client is crazy if it tries to destroy an RPC context for which
they have sent an RPCSEC_GSS_CREDPROBLEM, and so will refuse to talk to it
for a while.
The regression therefor probably was introduced by commit
0df7fb74fb.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The rest of the networking layer uses SOCK_ASYNC_NOSPACE to signal whether
or not we have someone waiting for buffer memory. Convert the SUNRPC layer
to use the same idiom.
Remove the unlikely()s in xs_udp_write_space and xs_tcp_write_space. In
fact, the most common case will be that there is nobody waiting for buffer
space.
SOCK_NOSPACE is there to tell the TCP layer whether or not the cwnd was
limited by the application window. Ensure that we follow the same idiom as
the rest of the networking layer here too.
Finally, ensure that we clear SOCK_ASYNC_NOSPACE once we wake up, so that
write_space() doesn't keep waking things up on xprt->pending.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
call_verify() can, under certain circumstances, free the RPC slot. In that
case, our cached pointer 'req = task->tk_rqstp' is invalid. Bug was
introduced in commit 220bcc2afd (SUNRPC:
Don't call xprt_release in call refresh).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* Use new node_to_cpumask_ptr. This creates a pointer to the
cpumask for a given node. This definition is in mm patch:
asm-generic-add-node_to_cpumask_ptr-macro.patch
* Use new set_cpus_allowed_ptr function.
Depends on:
[mm-patch]: asm-generic-add-node_to_cpumask_ptr-macro.patch
[sched-devel]: sched: add new set_cpus_allowed_ptr function
[x86/latest]: x86: add cpus_scnprintf function
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Greg Banks <gnb@melbourne.sgi.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.26: (1090 commits)
[NET]: Fix and allocate less memory for ->priv'less netdevices
[IPV6]: Fix dangling references on error in fib6_add().
[NETLABEL]: Fix NULL deref in netlbl_unlabel_staticlist_gen() if ifindex not found
[PKT_SCHED]: Fix datalen check in tcf_simp_init().
[INET]: Uninline the __inet_inherit_port call.
[INET]: Drop the inet_inherit_port() call.
SCTP: Initialize partial_bytes_acked to 0, when all of the data is acked.
[netdrvr] forcedeth: internal simplifications; changelog removal
phylib: factor out get_phy_id from within get_phy_device
PHY: add BCM5464 support to broadcom PHY driver
cxgb3: Fix __must_check warning with dev_dbg.
tc35815: Statistics cleanup
natsemi: fix MMIO for PPC 44x platforms
[TIPC]: Cleanup of TIPC reference table code
[TIPC]: Optimized initialization of TIPC reference table
[TIPC]: Remove inlining of reference table locking routines
e1000: convert uint16_t style integers to u16
ixgb: convert uint16_t style integers to u16
sb1000.c: make const arrays static
sb1000.c: stop inlining largish static functions
...
Add a new IB_WR_SEND_WITH_INV send opcode that can be used to mark a
"send with invalidate" work request as defined in the iWARP verbs and
the InfiniBand base memory management extensions. Also put "imm_data"
and a new "invalidate_rkey" member in a new "ex" union in struct
ib_send_wr. The invalidate_rkey member can be used to pass in an
R_Key/STag to be invalidated. Add this new union to struct
ib_uverbs_send_wr. Add code to copy the invalidate_rkey field in
ib_uverbs_post_send().
Fix up low-level drivers to deal with the change to struct ib_send_wr,
and just remove the imm_data initialization from net/sunrpc/xprtrdma/,
since that code never does any send with immediate operations.
Also, move the existing IB_DEVICE_SEND_W_INV flag to a new bit, since
the iWARP drivers currently in the tree set the bit. The amso1100
driver at least will silently fail to honor the IB_SEND_INVALIDATE bit
if passed in as part of userspace send requests (since it does not
implement kernel bypass work request queueing). Remove the flag from
all existing drivers that set it until we know which ones are OK.
The values chosen for the new flag is not consecutive to avoid clashing
with flags defined in the XRC patches, which are not merged yet but
which are already in use and are likely to be merged soon.
This resurrects a patch sent long ago by Mikkel Hagen <mhagen@iol.unh.edu>.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Commit 510deb0d was supposed to move the xprt_create_transport() call in
rpc_create(), but neglected to remove the old call site. This resulted in
a transport leak after every rpc_create() call.
This leak is present in 2.6.24 and 2.6.25.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fix a problem in _copy_to_pages(), whereby it may call flush_dcache_page()
with an invalid pointer due to the fact that 'pgto' gets incremented
beyond the end of the page array. Fix is to exit the loop without this
unnecessary increment of pgto.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The RDMACTXT_F_LAST_CTXT bit was getting set incorrectly
when the last chunk in the read-list spanned multiple pages. This
resulted in a kernel panic when the wrong context was used to
build the RPC iovec page list.
RDMA_READ is used to fetch RPC data from the client for
NFS_WRITE requests. A scatter-gather is used to map the
advertised client side buffer to the server-side iovec and
associated page list.
WR contexts are used to convey which scatter-gather entries are
handled by each WR. When the write data is large, a single RPC may
require multiple RDMA_READ requests so the contexts for a single RPC
are chained together in a linked list. The last context in this list
is marked with a bit RDMACTXT_F_LAST_CTXT so that when this WR completes,
the CQ handler code can enqueue the RPC for processing.
The code in rdma_read_xdr was setting this bit on the last two
contexts on this list when the last read-list chunk spanned multiple
pages. This caused the svc_rdma_recvfrom logic to incorrectly build
the RPC and caused the kernel to crash because the second-to-last
context doesn't contain the iovec page list.
Modified the condition that sets this bit so that it correctly detects
the last context for the RPC.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Tested-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The iWARP protocol limits RDMA read requests to a single scatter
entry. NFS/RDMA has code in rdma_read_max_sge() that is supposed to
limit the sge_count for RDMA read requests to 1, but the code to do
that is inside an #ifdef RDMA_TRANSPORT_IWARP block. In the mainline
kernel at least, RDMA_TRANSPORT_IWARP is an enum and not a
preprocessor #define, so the #ifdef'ed code is never compiled.
In my test of a kernel build with -j8 on an NFS/RDMA mount, this
problem eventually leads to trouble starting with:
svcrdma: Error posting send = -22
svcrdma : RDMA_READ error = -22
and things go downhill from there.
The trivial fix is to delete the #ifdef guard. The check seems to be
a remnant of when the NFS/RDMA code was not merged and needed to
compile against multiple kernel versions, although I don't think it
ever worked as intended. In any case now that the code is upstream
there's no need to test whether the RDMA_TRANSPORT_IWARP constant is
defined or not.
Without this patch, my kernel build on an NFS/RDMA mount using NetEffect
adapters quickly and 100% reproducibly failed with an error like:
ld: final link failed: Software caused connection abort
With the patch applied I was able to complete a kernel build on the
same setup.
(Tom Tucker says this is "actually an _ancient_ remnant when it had to
compile against iWARP vs. non-iWARP enabled OFA trees.")
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Acked-by: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The NFSv4 protocol allows clients to negotiate security protocols on the
fly in the case where an administrator on the server changes the export
settings and/or in the case where we may have a filesystem migration event.
Instead of having the NFS client code cache credentials that are tied to a
particular AUTH method it is therefore preferable to have a generic credential
that can be converted into whatever AUTH is in use by the RPC client when
the read/write/sillyrename/... is put on the wire.
We do this by means of the new "generic" credential, which basically just
caches the minimal information that is needed to look up an RPCSEC_GSS,
AUTH_SYS, or AUTH_NULL credential.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We need the ability to treat 'generic' creds specially, since they want to
bind instances of the auth cred instead of binding themselves.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add an rpc credential that is not tied to any particular auth mechanism,
but that can be cached by NFS, and later used to look up a cred for
whichever auth mechanism that turns out to be valid when the RPC call is
being made.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The current RPCAUTH_LOOKUP_ROOTCREDS flag only works for AUTH_SYS
authentication, and then only as a special case in the code. This patch
removes the auth_sys special casing, and replaces it with generic code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The assertion that checks for sge context overflow is
incorrectly hard-coded to 32. This causes a kernel bug
check when using big-data mounts. Changed the BUG_ON to
use the computed value RPCSVC_MAXPAGES.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
RDMA connection shutdown on an SMP machine can cause a kernel crash due
to the transport close path racing with the I/O tasklet.
Additional transport references were added as follows:
- A reference when on the DTO Q to avoid having the transport
deleted while queued for I/O.
- A reference while there is a QP able to generate events.
- A reference until the DISCONNECTED event is received on the CM ID
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
NFS: Fix dentry revalidation for NFSv4 referrals and mountpoint crossings
NFS: Fix the fsid revalidation in nfs_update_inode()
SUNRPC: Fix a nfs4 over rdma transport oops
NFS: Fix an f_mode/f_flags confusion in fs/nfs/write.c
Prevent an RPC oops when freeing a dynamically allocated RDMA
buffer, used in certain special-case large metadata operations.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: James Lentini <jlentini@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that we've tightened up the locking rules for RPC queue wakeups, we can
remove the RCU-safe kfree calls...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is designed to replace the timeout timer in the individual rpc_tasks.
By putting the timer function in the wait queue, we will eventually be able
to reduce the total number of timers in use by the RPC subsystem.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Use proc_create() to make sure that ->proc_fops be setup before gluing
PDE to main tree.
Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An audit of the current RPC timeout functions shows that they don't really
ever need to run in the softirq context. As long as the softirq is
able to signal that the wakeup is due to a timeout (which it can do by
setting task->tk_status to -ETIMEDOUT) then the callback functions can just
run as standard task->tk_callback functions (in the rpciod/process
context).
The only possible border-line case would be xprt_timer() for the case of
UDP, when the callback is used to reduce the size of the transport
congestion window. In testing, however, the effect of moving that update
to a callback would appear to be minor.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In all cases where we currently use rpc_wake_up_task(), we almost always
know on which waitqueue the rpc_task is actually sleeping. This will allows
us to simplify the queue locking in a future patch.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
All RPC timeout callback functions are expected to wake the task up. We can
enforce this by moving the wakeup back into rpc_run_timer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
A lot of the work done by the rpc_release() callback is inappropriate for
rpciod as it will often involve things like starting a new rpc call in
order to clean up state after an interrupted NFSv4 open() call, or
calls to mntput(), etc.
This patch allows the caller of rpc_run_task() to specify that the
rpc_release callback should run on a different workqueue than the default
rpciod_workqueue.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Sorry for the noise, but here's the v3 of this compilation fix :)
There are some places, which declare the char buf[...] on the stack
to push it later into dprintk(). Since the dprintk sometimes (if the
CONFIG_SYSCTL=n) becomes an empty do { } while (0) stub, these buffers
cause gcc to produce appropriate warnings.
Wrap these buffers with RPC_IFDEBUG macro, as Trond proposed, to
compile them out when not needed.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* Add path_put() functions for releasing a reference to the dentry and
vfsmount of a struct path in the right order
* Switch from path_release(nd) to path_put(&nd->path)
* Rename dput_path() to path_put_conditional()
[akpm@linux-foundation.org: fix cifs]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.
Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
<dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
struct path in every place where the stack can be traversed
- it reduces the overall code size:
without patch series:
text data bss dec hex filename
5321639 858418 715768 6895825 6938d1 vmlinux
with patch series:
text data bss dec hex filename
5320026 858418 715768 6894212 693284 vmlinux
This patch:
Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use updated file list for docbook files and
fix kernel-doc warnings in sunrpc:
Warning(linux-2.6.24-git12//net/sunrpc/rpc_pipe.c:689): No description found for parameter 'rpc_client'
Warning(linux-2.6.24-git12//net/sunrpc/rpc_pipe.c:765): No description found for parameter 'flags'
Warning(linux-2.6.24-git12//net/sunrpc/clnt.c:584): No description found for parameter 'tk_ops'
Warning(linux-2.6.24-git12//net/sunrpc/clnt.c:618): No description found for parameter 'bufsize'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
net/sunrpc/xprtrdma/svc_rdma_sendto.c:160: warning: format '%llx'
expects type 'long long unsigned int', but argument 3 has type 'u64'
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: When looping over RPC version and procedure numbers, use
unsigned index variables.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Move the initialzation in __svc_create_thread that happens prior to
thread creation to a new function. Export the function to allow
services to have better control over the svc_rqst structs.
Also rearrange the rqstp initialization to prevent NULL pointer
dereferences in svc_exit_thread in case allocations fail.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Add the svcrdma module to the xprtrdma makefile.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This logic parses the ONCRDMA protocol headers that
precede the actual RPC header. It is placed in a separate
file to keep all protocol aware code in a single place.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This file implements the RDMA transport sendto function. A RPC reply
on an RDMA transport consists of some number of RDMA_WRITE requests
followed by an RDMA_SEND request. The sendto function parses the
ONCRPC RDMA reply header to determine how to send the reply back to
the client. The send queue is sized so as to be able to send complete
replies for requests in most cases. In the event that there are not
enough SQ WR slots to reply, e.g. big data, the send will block the
NFSD thread. The I/O callback functions in svc_rdma_transport.c that
reap WR completions wake any waiters blocked on the SQ. In general,
the goal is not to block NFSD threads and the has_wspace method
stall requests when the SQ is nearly full.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This file implements the RDMA transport recvfrom function. The function
dequeues work reqeust completion contexts from an I/O list that it shares
with the I/O tasklet in svc_rdma_transport.c. For ONCRPC RDMA, an RPC may
not be complete when it is received. Instead, the RDMA header that precedes
the RPC message informs the transport where to get the RPC data from on
the client and where to place it in the RPC message before it is delivered
to the server. The svc_rdma_recvfrom function therefore, parses this RDMA
header and issues any necessary RDMA operations to fetch the remainder of
the RPC from the client.
Special handling is required when the request involves an RDMA_READ.
In this case, recvfrom submits the RDMA_READ requests to the underlying
transport driver and then returns 0. When the transport
completes the last RDMA_READ for the request, it enqueues it on a
read completion queue and enqueues the transport. The recvfrom code
favors this queue over the regular DTO queue when satisfying reads.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This file implements the core transport data management and I/O
path. The I/O path for RDMA involves receiving callbacks on interrupt
context. Since all the svc transport locks are _bh locks we enqueue the
transport on a list, schedule a tasklet to dequeue data indications from
the RDMA completion queue. The tasklet in turn takes _bh locks to
enqueue receive data indications on a list for the transport. The
svc_rdma_recvfrom transport function dequeues data from this list in an
NFSD thread context.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
![](/assets/img/avatar_default.png "\\\\"J. Bruce Fields\\\"){kind=avatar}
\\\"J. Bruce Fields\\\