A problem was reported via email, where a large (130000+) accumulation
of NFSv4 opens on an NFSv4 mount caused significant lock contention
on the mutex used to protect the client mount's open/lock state.
Although the root cause for the accumulation of opens was not
resolved, it is obvious that the NFSv4 client is not designed to
handle 100000+ opens efficiently. When searching for an open,
usually for a match by file handle, a linear search of all opens
is done.
This patch adds a table of hash lists for the opens, hashed on
file handle. This table will be used by future commits to
search for an open based on file handle more efficiently.
MFC after: 2 weeks
Recent discussion on the nfsv4@ietf.org mailing list confirmed
that an NFSv4 server should reply to an RPC in less than 1second.
If an NFSv4 RPC requires a delegation be recalled,
the server will attempt a CB_RECALL callback.
If the client is not responsive, the RPC reply will be delayed
until the callback times out.
Without this patch, the timeout is set to 4 seconds (set in
ticks, but used as seconds), resulting in the RPC reply taking over 4sec.
This patch redefines the constant as being in milliseconds and it
implements that for a value of 800msec, to ensure the RPC
reply is sent in less than 1second.
This patch only affects mounts from clients when delegations
are enabled on the server and the client is unresponsive to callbacks.
MFC after: 2 weeks
There is a NFSv4 file attribute called TimeCreate
that can be used for va_birthtime.
r362175 added some support for use of TimeCreate.
This patch completes support of va_birthtime by adding
support for setting this attribute to the server.
It also eanbles the client to
acquire and set the attribute for a NFSv4
server that supports the attribute.
Reviewed by: markj
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D30156
When loading attributes from the cache, the NFS client is careful to
copy only the fields that it initialized. After fetching attributes
from the server, however, it would copy the entire vattr structure
initialized from the RPC response, so uninitialized stack bytes would
end up being copied to userspace. In particular, va_birthtime (v2 and
v3) and va_gen (v3) had this problem.
Use a common subroutine to copy fields provided by the NFS client, and
ensure that we provide a dummy va_gen for the v3 case.
Reviewed by: rmacklem
Reported by: KMSAN
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D30090
For a pNFS mount, the NFSv4.1/4.2 client uses compound RPCs that
have both Open and LayoutGet operations in them.
If the pNFS server were tp reply NFSERR_DELAY for one of these
compounds, the retry after a delay cannot be handled by
newnfs_request(), since there is a reference held on the open
state for the Open operation in them.
Fix this by adding these RPCs to the "don't do delay here"
list in newnfs_request().
This patch is only needed if the mount is using pNFS (the "pnfs"
mount option) and probably only matters if the MDS server
is issuing delegations as well as pNFS layouts.
Found by code inspection.
MFC after: 2 weeks
Commit 4281bfec36 patched the server so that the
callback session slot would be free'd for reuse when
a callback attempt fails.
However, this can often result in the sequence# for
the session slot to be advanced such that the client
end will reply NFSERR_SEQMISORDERED.
To avoid the NFSERR_SEQMISORDERED client reply,
this patch negates the sequence# advance for the
case where the callback has failed.
The common case is a failed back channel, where
the callback cannot be sent to the client, and
not advancing the sequence# is correct for this
case. For the uncommon case where the client's
reply to the callback is lost, not advancing the
sequence# will indicate to the client that the
next callback is a retry and not a new callback.
But, since the FreeBSD server always sets "csa_cachethis"
false in the callback sequence operation, a retry
and a new callback should be handled the same way
by the client, so this should not matter.
Until you have this patch in your NFSv4.1/4.2 server,
you should consider avoiding the use of delegations.
Even with this patch, interoperation with the
Linux NFSv4.1/4.2 client in kernel versions prior
to 5.3 can result in frequent 15second delays if
delegations are enabled. This occurs because, for
kernels prior to 5.3, the Linux client does a TCP
reconnect every time it sees multiple concurrent
callbacks and then it takes 15seconds to recover
the back channel after doing so.
MFC after: 2 weeks
After a vnode is recycled it can no longer be
acquired via vfs_hash_get() and, as such,
a delegation for the vnode cannot be recalled.
In the unlikely event that a delegation still
exists when the vnode is being recycled, return
the delegation since it will no longer be
recallable.
Until you have this patch in your NFSv4 client,
you should consider avoiding the use of delegations.
MFC after: 2 weeks
This reverts commit 9edaceca81.
It turns out that the Linux client intentionally does an NFSv4.1
RPC with only a Sequence operation in it and with "seqid + 1"
for the slot. This is used to re-synchronize the slot's seqid
and the client expects the NFS4ERR_SEQ_MISORDERED error reply.
As such, revert the patch, so that the server remains RFC5661
compliant.
Recent testing of network partitioning a FreeBSD NFSv4.1
server from a Linux NFSv4.1 client identified problems
with both the FreeBSD server and Linux client.
Sometimes, after some Linux NFSv4.1/4.2 clients establish
a new TCP connection, they will advance the sequence number
for a session slot by 2 instead of 1.
RFC5661 specifies that a server should reply
NFS4ERR_SEQ_MISORDERED for this case.
This might result in a system call error in the client and
seems to disable future use of the slot by the client.
Since advancing the sequence number by 2 seems harmless,
allow this case if vfs.nfs.linuxseqsesshack is non-zero.
Note that, if the order of RPCs is actually reversed,
a subsequent RPC with a smaller sequence number value
for the slot will be received. This will result in
a NFS4ERR_SEQ_MISORDERED reply.
This has not been observed during testing.
Setting vfs.nfs.linuxseqsesshack to 0 will provide
RFC5661 compliant behaviour.
This fix affects the fairly rare case where a NFSv4
Linux client does a TCP reconnect and then apparently
erroneously increments the sequence number for the
session slot twice during the reconnect cycle.
PR: 254816
MFC after: 2 weeks
During a recent testing event, it was reported that the NFSv4.1/4.2
server erroneously bound the back channel to a new TCP connection.
RFC5661 specifies that the fore channel is implicitly bound to a
new TCP connection when an RPC with Sequence (almost any of them)
is done on it. For the back channel to be bound to the new TCP
connection, an explicit BindConnectionToSession must be done as
the first RPC on the new connection.
Since new TCP connections are created by the "reconnect" layer
(sys/rpc/clnt_rc.c) of the krpc, this patch adds an optional
upcall done by the krpc whenever a new connection is created.
The patch also adds the specific upcall function that does a
BindConnectionToSession and configures the krpc to call it
when required.
This is necessary for correct interoperability with NFSv4.1/NFSv4.2
servers when the nfscbd daemon is running.
If doing NFSv4.1/NFSv4.2 mounts without this patch, it is
recommended that the nfscbd daemon not be running and that
the "pnfs" mount option not be specified.
PR: 254840
Comments by: asomers
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D29475
Recent testing of network partitioning a FreeBSD NFSv4.1
server from a Linux NFSv4.1 client identified problems
with both the FreeBSD server and Linux client.
Commit 05a39c2c1c fixed replying with the cached reply in
in the session slot if same session slot sequence#.
However, the code uses the reply and, as such,
will fail for a subsequent retry of the RPC.
A subsequent retry would be an extremely rare event,
but this patch fixes this, so long as m_copym(..M_NOWAIT)
does not fail, which should also be a rare event.
This fix affects the exceedingly rare case where a NFSv4
client retries a non-idempotent RPC, such as a lock
operation, multiple times. Note that retries only occur
after the client has needed to create a new TCP connection,
with a new TCP connection for each retry.
MFC after: 2 weeks
Commit 01ae8969a9 stopped the NFSv4.1/4.2 server from implicitly
binding the back channel to a new TCP connection so that it
conforms to RFC5661, for NFSv4.1/4.2. An effect of this
for the Linux NFS client is that it will do a
BindConnectionToSession when it sees NFSV4SEQ_CBPATHDOWN
set in a sequence reply. This will fix the back channel, but the
first attempt at a callback like CB_RECALL will already have
failed. Without this patch, a CB_RECALL will not be retried
and that can result in a 5 minute delay until the delegation
times out.
This patch modifies the code so that it will retry the
CB_RECALL every couple of seconds, often avoiding the
5 minute delay.
This is not critical for correct behaviour, but avoids
the 5 minute delay for the case where the Linux client
re-binds the back channel via BindConnectionToSession.
MFC after: 2 weeks
During a recent NFSv4 testing event a test server caused a hang
where "umount -N" failed. The renew thread was sleeping on "nfsv4lck"
and the "umount" was sleeping, waiting for the renew thread to
terminate.
This is the first of two patches that is hoped to fix the renew thread
so that it will terminate when "umount -N" is done on the mount.
nfsv4_lock() checks for forced dismount, but only after it wakes up
from msleep(). Without this patch, a wakeup() call was required.
This patch adds a 1second timeout on the msleep(), so that it will
wake up and see the forced dismount flag. Normally a wakeup()
will occur in less than 1second, but if a premature return from
msleep() does occur, it will simply loop around and msleep() again.
While here, replace the nfsmsleep() wrapper that was used for portability
with the actual msleep() call and make the same change for nfsv4_getref().
MFC after: 2 weeks
During a recent virtual NFSv4 testing event, a bug in the FreeBSD client
was detected when doing I/O DS operations on a Flexible File Layout pNFS
server. For an NFSv3 DS, the Read/Write/Commit nfsstats were incremented
instead of the ReadDS/WriteDS/CommitDS counts.
This patch fixes this.
Only the RPC counts reported by nfsstat(1) were affected by this bug,
the I/O operations were performed correctly.
MFC after: 2 weeks
We provide these for compat with other queue.h headers since some software
assumes it exists (e.g. the libevent contrib code), but we are not
encouraging their use (NULL should be used instead).
This fixes the following warning (which should arguable be an error since
it results in a function call to an undefined function):
.../contrib/libevent/buffer.c:495:16: warning: implicit declaration of function 'LIST_END' is invalid in C99 [-Wimplicit-function-declaration]
cbent != LIST_END(&buffer->callbacks);
^
.../contrib/libevent/buffer.c:495:13: warning: comparison between pointer and integer ('struct evbuffer_cb_entry *' and 'int') [-Wpointer-integer-compare]
cbent != LIST_END(&buffer->callbacks);
~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Reviewed By: jhb
Differential Revision: https://reviews.freebsd.org/D27151
Commit 774a36851e fixed the NFS server so that it could handle
ERELOOKUP returns from VOP calls by redoing the operation/RPC.
However, for NFSv4.0, redoing an Open would increment
the open_owner's seqid multiple times, breaking the protocol.
This patch sets a new flag called ND_ERELOOKUP on the RPC when
a redo is in progress. Then the code that increments the seqid
avoids the seqid increment/check when the flag is set, since
it indicates this has already been done for the Open.
r367672 modified UFS such that certain VOPs, such as
VOP_CREATE() will intermittently return ERELOOKUP.
When this happens, the entire system call, or NFS
operation in the case of the NFS server, must be redone.
This patch adds that support to the NFS server by rolling
back the state of the NFS request arguments and NFS
reply arguments mbuf lists to the condition they were
in before the operation and then redoing the operation.
Tested by: pho
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D27875
When using NFS-over-TLS, an NFS client can optionally provide an X.509
certificate to the server during the TLS handshake. For some situations,
such as different NFS servers or different certificates being mapped
to different user credentials on the NFS server, there may be a need
for different mounts to provide different certificates.
This new mount option called "tlscertname" may be used to specify a
non-default certificate be provided. This alernate certificate will
be stored in /etc/rpc.tlsclntd in a file with a name based on what is
provided by this mount option.
The argument is a void * so there's no need to cast it to caddr_t.
Update documentation to match function decleration.
Reviewed by: freqlabs
Obtained from: CheriBSD
MFC after: 1 week
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D27093
FreeBSD's NFS exporter has long exported some unused statistics fields.
Revision r366992 removed them from nfsstat. This revision renames those
fields in the kernel's exported structures to make it clear to other
consumers that they are unused.
Reported by: emaste
Reviewed by: emaste
Sponsored by: Axcient
Differential Revision: https://reviews.freebsd.org/D27258
The pointer to vnode is already stored into f_vnode, so f_data can be
reused. Fix all found users of f_data for DTYPE_VNODE.
Provide finit_vnode() helper to initialize file of DTYPE_VNODE type.
Reviewed by: markj (previous version)
Discussed with: freqlabs (openzfs chunk)
Tested by: pho (previous version)
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D26346
An Internet Draft titled "Towards Remote Procedure Call Encryption By Default"
(soon to be an RFC I think) describes how Sun RPC is to use TLS with NFS
as a specific application case.
Various commits prepared the NFS code to use KERN_TLS, mainly enabling use
of ext_pgs mbufs for large RPC messages.
r364475 added TLS support to the kernel RPC.
This commit (which is the final one for kernel changes required to do
NFS over TLS) adds support for three export flags:
MNT_EXTLS - Requires a TLS connection.
MNT_EXTLSCERT - Requires a TLS connection where the client presents a valid
X.509 certificate during TLS handshake.
MNT_EXTLSCERTUSER - Requires a TLS connection where the client presents a
valid X.509 certificate with "user@domain" in the otherName
field of the SubjectAltName during TLS handshake.
Without these export options, clients are permitted, but not required, to
use TLS.
For the client, a new nmount(2) option called "tls" makes the client do
a STARTTLS Null RPC and TLS handshake for all TCP connections used for the
mount. The CLSET_TLS client control option is used to indicate to the kernel RPC
that this should be done.
Unless the above export flags or "tls" option is used, semantics should
not change for the NFS client nor server.
For NFS over TLS to work, the userspace daemons rpctlscd(8) { for client }
or rpctlssd(8) daemon { for server } must be running.
This is a partial revert of r363210, since the "use_ext" argument added
by that commit is not actually useful.
This patch should not result in any semantics change.
For NFSv4.0, the server creates a server->client TCP connection for callbacks.
If the client mount on the server is using TLS, enable TLS for this callback
TCP connection.
TLS connections from clients will not be supported until the kernel RPC
changes are committed.
Since this changes the internal ABI between the NFS kernel modules that
will require a version bump, delete newnfs_trimtrailing(), which is no
longer used.
Since LCL_TLSCB is not yet set, these changes should not have any semantic
affect at this time.
and getxattr operations.
This patch optionally enables generation of read, readlink and getxattr replies
in ext_pgs mbufs. Since neither of ND_EXTPG or ND_TLS are currently ever set,
there is no change in semantics at this time.
It also corrects the message in a couple of panic()s that should never occur.
This is another in the series of commits that add support to the NFS client
and server for building RPC messages in ext_pgs mbufs with anonymous pages.
This is useful so that the entire mbuf list does not need to be
copied before calling sosend() when NFS over TLS is enabled.
Use of ext_pgs mbufs will not be enabled until the kernel RPC is updated
to handle TLS.
trying to set it.
r362490 added support for setting of the TimeCreate (va_birthtime) attribute,
but it does so without checking to see if the server supports the attribute.
This could result in NFSERR_ATTRNOTSUPP error replies to the Setattr operation.
This patch adds code to check that the server supports TimeCreate before
attempting to do a Setattr of it to avoid these error returns.
This patch uses a slightly different algorithm for nfsrv_adj()
since ext_pgs mbuf lists are not permitted to have m_len == 0 mbufs.
As such, the code now frees mbufs after the adjustment in the list instead
of setting their m_len field to 0.
Since mbuf(s) may be trimmed off the tail of the list, the function now
returns a pointer to the last mbuf in the list. This saves the caller
from needing to use m_last() to find the last mbuf.
It also implies that it might return a nul list, which required a check for
that in nfsrvd_readlink().
This is another in the series of commits that add support to the NFS client
and server for building RPC messages in ext_pgs mbufs with anonymous pages.
This is useful so that the entire mbuf list does not need to be
copied before calling sosend() when NFS over TLS is enabled.
Use of ext_pgs mbufs will not be enabled until the kernel RPC is updated
to handle TLS.
This patch uses a slightly different algorithm for nfsm_uiombuflist() for
the non-ext_pgs case, where a variable called "mcp" is maintained, pointing to
the current location that mbuf data can be filled into. This avoids use of
mtod(mp, char *) + mp->m_len to calculate the location, since this does
not work for ext_pgs mbufs and I think it makes the algorithm more readable.
This change should not result in semantic changes for the non-ext_pgs case.
The patch also deletes come unneeded code.
It also adds support for anonymous page ext_pgs mbufs to nfsm_split().
This is another in the series of commits that add support to the NFS client
and server for building RPC messages in ext_pgs mbufs with anonymous pages.
This is useful so that the entire mbuf list does not need to be
copied before calling sosend() when NFS over TLS is enabled.
At this time for this case, use of ext_pgs mbufs cannot be enabled, since
ktls_encrypt() replaces the unencrypted data with encrypted data in place.
Until such time as this can be enabled, there should be no semantic change.
Also, note that this code is only used by the NFS client for a mirrored pNFS
server.
This is another in the series of commits that add support to the NFS client
and server for building RPC messages in ext_pgs mbufs with anonymous pages.
This is useful so that the entire mbuf list does not need to be
copied before calling sosend() when NFS over TLS is enabled.
Since ND_EXTPG is never set yet, there is no semantic change at this time.
Also, add a new function nfsm_add_ext_pgs() which will either add a page
or add a new ext_pgs mbuf with a page to the mbuf list. Used by nfsm_strtom().
This is another in the series of commits that add support to the NFS client
and server for building RPC messages in ext_pgs mbufs with anonymous pages.
This is useful so that the entire mbuf list does not need to be
copied before calling sosend() when NFS over TLS is enabled.
Since ND_EXTPG is never set yet, there is no semantic change at this time.
This is another in the series of commits that add support to the NFS client
and server for building RPC messages in ext_pgs mbufs with anonymous pages.
This is useful so that the entire mbuf list does not need to be
copied before calling sosend() when NFS over TLS is enabled.
Since ND_EXTPG is never set yet, there is no semantic change at this time.
This is the first of a series of commits that add support to the NFS client
and server for building RPC messages in ext_pgs mbufs with anonymous pages.
This is useful so that the entire mbuf list does not need to be
copied before calling sosend() when NFS over TLS is enabled.
Since ND_EXTPG is never set yet, there is no semantic change at this time.
should be used.
For KERN_TLS (and possibly some other future network interface) the mbuf
list passed into sosend() must be ext_pgs mbufs. The krpc could simply
copy all the mbuf data into ext_pgs mbufs before calling sosend(), but
that would be inefficient for large RPC messages.
This patch adds an argument to nfscl_reqstart() to indicate that it should
fill the RPC message into ext_pgs mbufs.
It also adds fields to "struct nfsrv_descript" needed for building NFS RPC
messages in ext_pgs mbufs, along with new flags for this.
Since the argument is always "false", this commit should not result in any
semantic change. However, this commit prepares the code
for future commits that will add support for building of NFS RPC messages
in ext_pgs mbufs.
These macro definitions are no longer needed as the NFS OSX port is long
dead. The vfs_statfs macro conflicts with the vfsops field of the same
name.
Submitted by: shivank@
Reviewed by: rmacklem
MFC after: 2 weeks
Sponsored by: Google, Inc. (GSoC 2020)
Differential Revision: https://reviews.freebsd.org/D25263
Since mnt_flags was upgraded to 64bits there has been a quirk in
"struct export_args", since it hold a copy of mnt_flags
in ex_flags, which is an "int" (32bits).
This happens to currently work, since all the flag bits used in ex_flags are
defined in the low order 32bits. However, new export flags cannot be defined.
Also, ex_anon is a "struct xucred", which limits it to 16 additional groups.
This patch revises "struct export_args" to make ex_flags 64bits and replaces
ex_anon with ex_uid, ex_ngroups and ex_groups (which points to a
groups list, so it can be malloc'd up to NGROUPS in size.
This requires that the VFS_CHECKEXP() arguments change, so I also modified the
last "secflavors" argument to be an array pointer, so that the
secflavors could be copied in VFS_CHECKEXP() while the export entry is locked.
(Without this patch VFS_CHECKEXP() returns a pointer to the secflavors
array and then it is used after being unlocked, which is potentially
a problem if the exports entry is changed.
In practice this does not occur when mountd is run with "-S",
but I think it is worth fixing.)
This patch also deleted the vfs_oexport_conv() function, since
do_mount_update() does the conversion, as required by the old vfs_cmount()
calls.
Reviewed by: kib, freqlabs
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D25088
Comparing fsid_t objects requires internal knowledge of the fsid structure
and yet this is duplicated across a number of places in the code.
Simplify by creating a fsidcmp function (macro).
Reviewed by: mjg, rmacklem
Approved by: mav (mentor)
MFC after: 1 week
Sponsored by: iXsystems, Inc.
Differential Revision: https://reviews.freebsd.org/D24749
mbuf lists.
This function is currently trivial, but will that will change when
support for building NFS messages in ext_pgs mbufs is added.
Adding support for ext_pgs mbufs is needed for KERN_TLS, which will
be used to implement nfs-over-tls.
The NFS function called newnfs_trimleading() has not been used by the
code in long time. To give you a clue, it still had a K&R style function
declaration.
Delete it, since it is just cruft, as a part of the NFS mbuf handling
cleanup in preparation for adding ext_pgs mbuf support.
The ext_pgs mbuf support for the build/send side is needed by
nfs-over-tls.
r360514 prepared the NFS code for changes to handle ext_pgs mbufs on
the receive side. However, at this time, KERN_TLS does not pass
ext_pgs mbufs up through soreceive(). As such, as this time, only
the send/build side of the NFS mbuf code needs to handle ext_pgs mbufs.
Revert r360514 since the rather extensive changes required for receive
side ext_pgs mbufs are not yet needed.
This avoids unnecessary churn of the sources.
Factoring some of the code in nfsm_dissct() out into separate functions
allows these functions to be used elsewhere in the NFS mbuf handling code.
Other uses of these functions will be done in future commits.
It also makes it easier to add support for ext_pgs mbufs, which is needed
for nfs-over-tls under development in base/projects/nfs-over-tls.
Although the algorithm in nfsm_dissct() is somewhat re-written by this
patch, the semantics of nfsm_dissct() should not have changed.
The NFS code had a bunch of Mac OS/X accessor functions named uio_XXX
left over from the port to Mac OS/X. Since that port is long forgotten,
replace the calls with the code generated by the FreeBSD macros for these
in nfskpiport.h. This allows the macros to be deleted from nfskpiport.h
and I think makes the code more readable.
This patch should not result in any semantic change.
