We recently received a patch for fs/exportfs/expfs.c, but there
isn't a subsystem maintainer listed for fs/exportfs:

Christian Brauner <brauner@kernel.org> (commit_signer:2/2=100%,authored:1/2=50%,added_lines:3/6=50%,removed_lines:2/6=33%)
Al Viro <viro@zeniv.linux.org.uk> (commit_signer:1/2=50%,authored:1/2=50%,added_lines:3/6=50%,removed_lines:4/6=67%)
Miklos Szeredi <mszeredi@redhat.com> (commit_signer:1/2=50%)
Amir Goldstein <amir73il@gmail.com> (commit_signer:1/2=50%)
linux-kernel@vger.kernel.org (open list)

Neil says:
> Looking at recent commits, patches come in through multiple
> different trees.
> nfsd certainly has an interest in expfs.c.  The only other user is
> name_to_handle/open_by_handle API.
> I see it as primarily nfsd functionality which is useful enough to
> be exported directly to user-space.
> (It was created by me when I was nfsd maintainer - does that
> count?)
Suggested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Jeff Layton <jlayton@kernel.org>

Add a missing SPDX header.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

fh_match() is costly, especially when filehandles are large (as is
the case for NFSv4). It needs to be used sparingly when searching
data structures. Unfortunately, with common workloads, I see
multiple thousands of objects stored in file_hashtbl[], which has
just 256 buckets, making its bucket hash chains quite lengthy.

Walking long hash chains with the state_lock held blocks other
activity that needs that lock. Sizable hash chains are a common
occurrance once the server has handed out some delegations, for
example -- IIUC, each delegated file is held open on the server by
an nfs4_file object.

To help mitigate the cost of searching with fh_match(), replace the
nfs4_file hash table with an rhashtable, which can dynamically
resize its bucket array to minimize hash chain length.

The result of this modification is an improvement in the latency of
NFSv4 operations, and the reduction of nfsd CPU utilization due to
eliminating the cost of multiple calls to fh_match() and reducing
the CPU cache misses incurred while walking long hash chains in the
nfs4_file hash table.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

find_file() is now the only caller of find_file_locked(), so just
fold these two together.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

Remove the call to find_file_locked() in insert_nfs4_file(). Tracing
shows that over 99% of these calls return NULL. Thus it is not worth
the expense of the extra bucket list traversal. insert_file() already
deals correctly with the case where the item is already in the hash
bucket.

Since nfsd4_file_hash_insert() is now just a wrapper around
insert_file(), move the meat of insert_file() into
nfsd4_file_hash_insert() and get rid of it.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>

Refactor to relocate hash deletion operation to a helper function
that is close to most other nfs4_file data structure operations.

The "noinline" annotation will become useful in a moment when the
hlist_del_rcu() is replaced with a more complex rhash remove
operation. It also guarantees that hash remove operations can be
traced with "-p function -l remove_nfs4_file_locked".

This also simplifies the organization of forward declarations: the
to-be-added rhashtable and its param structure will be defined
/after/ put_nfs4_file().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

Name this function more consistently. I'm going to use nfsd4_file_
and nfsd4_file_hash_ for these helpers.

Change the @fh parameter to be const pointer for better type safety.

Finally, move the hash insertion operation to the caller. This is
typical for most other "init_object" type helpers, and it is where
most of the other nfs4_file hash table operations are located.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

Enable callers to use const pointers for type safety.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

Enable callers to use const pointers where they are able to.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>

Delegation revocation is an exceptional event that is not otherwise
visible externally (eg, no network traffic is emitted). Generate a
trace record when it occurs so that revocation can be observed or
other activity can be triggered. Example:

nfsd-1104  [005]  1912.002544: nfsd_stid_revoke:        client 633c9343:4e82788d stateid 00000003:00000001 ref=2 type=DELEG

Trace infrastructure is provided for subsequent additional tracing
related to nfs4_stid activity.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

Handing out a delegation stateid is recorded with the
nfsd_deleg_read tracepoint, but there isn't a matching tracepoint
for recording when the stateid is returned.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

Remove the lame-duck dprintk()s around nfs4_preprocess_stateid_op()
call sites.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>

Record what we've learned recently about the NFSD filecache in a
documenting comment so our future selves don't forget what all this
is for.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

NFSv4 operations manage the lifetime of nfsd_file items they use by
means of NFSv4 OPEN and CLOSE. Hence there's no need for them to be
garbage collected.

Introduce a mechanism to enable garbage collection for nfsd_file
items used only by NFSv2/3 callers.

Note that the change in nfsd_file_put() ensures that both CLOSE and
DELEGRETURN will actually close out and free an nfsd_file on last
reference of a non-garbage-collected file.

Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=394Suggested-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

This reverts commit 5e138c4a.

That commit attempted to make files available to other users as soon
as all NFSv4 clients were done with them, rather than waiting until
the filecache LRU had garbage collected them.

It gets the reference counting wrong, for one thing.

But it also misses that DELEGRETURN should release a file in the
same fashion. In fact, any nfsd_file_put() on an file held open
by an NFSv4 client needs potentially to release the file
immediately...

Clear the way for implementing that idea.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>

In a moment I'm going to introduce separate nfsd_file types, one of
which is garbage-collected; the other, not. The garbage-collected
variety is to be used by NFSv2 and v3, and the non-garbage-collected
variety is to be used by NFSv4.

nfsd_commit() is invoked by both NFSv3 and NFSv4 consumers. We want
nfsd_commit() to find and use the correct variety of cached
nfsd_file object for the NFS version that is in use.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>

We had a report of this:

    BUG: sleeping function called from invalid context at fs/nfsd/filecache.c:440

...with a stack trace showing nfsd_file_put being called from
nfs4_show_open. This code has always tried to call fput while holding a
spinlock, but we recently changed this to use the filecache, and that
started triggering the might_sleep() in nfsd_file_put.

states_start takes and holds the cl_lock while iterating over the
client's states, and we can't sleep with that held.

Have the various nfs4_show_* functions instead hold the fi_lock instead
of taking a nfsd_file reference.

Fixes: 78599c42 ("nfsd4: add file to display list of client's opens")
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2138357Reported-by: Zhi Li <yieli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

expfs.c has a bunch of dprintk statements which are unusable due to:
 #define dprintk(fmt, args...) do{}while(0)
Use pr_debug so that they can be enabled dynamically.
Also make some minor changes to the debug statements to fix some
incorrect types, and remove __func__ which can be handled by dynamic
debug separately.
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

rpc.nfsd stopped supporting NFSv2 a year ago. Take the next logical
step toward deprecating it and allow NFSv2 support to be compiled out.

Add a new CONFIG_NFSD_V2 option that can be turned off and rework the
CONFIG_NFSD_V?_ACL option dependencies. Add a description that
discourages enabling it.

Also, change the description of CONFIG_NFSD to state that the always-on
version is now 3 instead of 2.

Finally, add an #ifdef around "case 2:" in __write_versions. When NFSv2
is disabled at compile time, this should make the kernel ignore attempts
to disable it at runtime, but still error out when trying to enable it.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

nfserrno() is common to all nfs versions, but nfsproc.c is specifically
for NFSv2. Move it to vfs.c, and the prototype to vfs.h.

While we're in here, remove the #ifdef EDQUOT check in this function.
It's apparently a holdover from the initial merge of the nfsd code in
1997. No other place in the kernel checks that that symbol is defined
before using it, so I think we can dispense with it here.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

The kernel currently errors out if you attempt to enable or disable a
version that it doesn't recognize. Change it to ignore attempts to
disable an unrecognized version. If we don't support it, then there is
no harm in doing so.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

For some reason, the NFSv2 GETACL result encoder was fully converted
to use the new nfs_stream_encode_acl(), but the NFSv3 equivalent was
not similarly converted.

Fixes: 20798dfe ("NFSD: Update the NFSv3 GETACL result encoder to use struct xdr_stream")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

The xdr_stream conversion inadvertently left some code that set the
page_len of the send buffer. The XDR stream encoders should handle
this automatically now.

This oversight adds garbage past the end of the Reply message.
Clients typically ignore the garbage, but NFSD does not need to send
it, as it leaks stale memory contents onto the wire.

Fixes: f8cba473 ("NFSD: Update the NFSv2 GETACL result encoder to use struct xdr_stream")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Clean up after commit 22700f3c ("SUNRPC: Improve ordering of
transport processing").
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Variable host_err is assigned a value that is never read, it is being
re-assigned a value in every different execution path in the following
switch statement. The assignment is redundant and can be removed.

Cleans up clang-scan warning:
warning: Value stored to 'host_err' is never read [deadcode.DeadStores]
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Chuck had suggested reverting READ_PLUS so it returns a single DATA
segment covering the requested read range. This prepares the server for
a future "sparse read" function so support can easily be added without
needing to rip out the old READ_PLUS code at the same time.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Pull vfs fix from Al Viro:
 "Amir's copy_file_range() fix"

* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: fix copy_file_range() averts filesystem freeze protection

Pull USB fixes from Greg KH:
 "Here are some small USB fixes for 6.1-rc7 that resolve some reported
  problems:

   - cdnsp driver fixes for reported problems

   - dwc3 fixes for some small reported problems

   - uvc gadget driver fix for reported regression

  All of these have been in linux-next with no reported problems"

* tag 'usb-6.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: cdnsp: fix issue with ZLP - added TD_SIZE = 1
  usb: dwc3: gadget: Clear ep descriptor last
  usb: dwc3: exynos: Fix remove() function
  usb: cdnsp: Fix issue with Clear Feature Halt Endpoint
  usb: dwc3: gadget: Disable GUSB2PHYCFG.SUSPHY for End Transfer
  usb: gadget: uvc: also use try_format in set_format

Pull char/misc driver fixes from Greg KH:
 "Here are some small driver fixes for 6.1-rc7, they include:

   - build warning fix for the vdso when using new versions of grep

   - iio driver fixes for reported issues

   - small nvmem driver fixes

   - fpga Kconfig fix

   - interconnect dt binding fix

  All of these have been in linux-next with no reported issues"

* tag 'char-misc-6.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  lib/vdso: use "grep -E" instead of "egrep"
  nvmem: lan9662-otp: Change return type of lan9662_otp_wait_flag_clear()
  nvmem: rmem: Fix return value check in rmem_read()
  fpga: m10bmc-sec: Fix kconfig dependencies
  dt-bindings: iio: adc: Remove the property "aspeed,trim-data-valid"
  iio: adc: aspeed: Remove the trim valid dts property.
  iio: core: Fix entry not deleted when iio_register_sw_trigger_type() fails
  iio: accel: bma400: Fix memory leak in bma400_get_steps_reg()
  iio: light: rpr0521: add missing Kconfig dependencies
  iio: health: afe4404: Fix oob read in afe4404_[read|write]_raw
  iio: health: afe4403: Fix oob read in afe4403_read_raw
  iio: light: apds9960: fix wrong register for gesture gain
  dt-bindings: interconnect: qcom,msm8998-bwmon: Correct SC7280 CPU compatible

Pull timer fix from Borislav Petkov:

 - Return the proper timer register width (31 bits) for a 32-bit signed
   register in order to avoid a timer interrupt storm on ARM XGene-1
   hardware running in NO_HZ mode

* tag 'timers_urgent_for_v6.1_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/drivers/arm_arch_timer: Fix XGene-1 TVAL register math error

Pull objtool fix from Borislav Petkov:

 - Handle different output of readelf on different distros running
   ppc64le which confuses faddr2line's function offsets conversion

* tag 'objtool_urgent_for_v6.1_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  scripts/faddr2line: Fix regression in name resolution on ppc64le

Pull x86 fixes from Borislav Petkov:

 - ioremap: mask out the bits which are not part of the physical address
   *after* the size computation is done to prevent any hypothetical
   ioremap failures

 - Change the MSR save/restore functionality during suspend to rely on
   flags denoting that the related MSRs are actually supported vs
   reading them and assuming they are (an Atom one allows reading but
   not writing, thus breaking this scheme at resume time)

 - prevent IV reuse in the AES-GCM communication scheme between SNP
   guests and the AMD secure processor

* tag 'x86_urgent_for_v6.1_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ioremap: Fix page aligned size calculation in __ioremap_caller()
  x86/pm: Add enumeration check before spec MSRs save/restore setup
  x86/tsx: Add a feature bit for TSX control MSR support
  virt/sev-guest: Prevent IV reuse in the SNP guest driver

Pull perf fixes from Borislav Petkov:
 "Two more fixes to the perf sigtrap handling:

   - output the address in the sample only when it has been requested

   - handle the case where user-only events can hit in kernel and thus
     upset the sigtrap sanity checking"

* tag 'perf_urgent_for_v6.1_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Consider OS filter fail
  perf: Fixup SIGTRAP and sample_flags interaction

Pull kvm fixes from Paolo Bonzini:
 "x86:

   - Fixes for Xen emulation. While nobody should be enabling it in the
     kernel (the only public users of the feature are the selftests),
     the bug effectively allows userspace to read arbitrary memory.

   - Correctness fixes for nested hypervisors that do not intercept INIT
     or SHUTDOWN on AMD; the subsequent CPU reset can cause a
     use-after-free when it disables virtualization extensions. While
     downgrading the panic to a WARN is quite easy, the full fix is a
     bit more laborious; there are also tests. This is the bulk of the
     pull request.

   - Fix race condition due to incorrect mmu_lock use around
     make_mmu_pages_available().

  Generic:

   - Obey changes to the kvm.halt_poll_ns module parameter in VMs not
     using KVM_CAP_HALT_POLL, restoring behavior from before the
     introduction of the capability"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Update gfn_to_pfn_cache khva when it moves within the same page
  KVM: x86/xen: Only do in-kernel acceleration of hypercalls for guest CPL0
  KVM: x86/xen: Validate port number in SCHEDOP_poll
  KVM: x86/mmu: Fix race condition in direct_page_fault
  KVM: x86: remove exit_int_info warning in svm_handle_exit
  KVM: selftests: add svm part to triple_fault_test
  KVM: x86: allow L1 to not intercept triple fault
  kvm: selftests: add svm nested shutdown test
  KVM: selftests: move idt_entry to header
  KVM: x86: forcibly leave nested mode on vCPU reset
  KVM: x86: add kvm_leave_nested
  KVM: x86: nSVM: harden svm_free_nested against freeing vmcb02 while still in use
  KVM: x86: nSVM: leave nested mode on vCPU free
  KVM: Obey kvm.halt_poll_ns in VMs not using KVM_CAP_HALT_POLL
  KVM: Avoid re-reading kvm->max_halt_poll_ns during halt-polling
  KVM: Cap vcpu->halt_poll_ns before halting rather than after

Pull cifs fixes from Steve French:
 "Two small cifs/smb3 client fixes:

   - an unlock missing in an error path in copychunk_range found by
     xfstest 476

   - a fix for a use after free in a debug code path"

* tag '6.1-rc6-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix missing unlock in cifs_file_copychunk_range()
  cifs: Use after free in debug code

Merge tag 'kbuild-fixes-v6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Fix CC_HAS_ASM_GOTO_TIED_OUTPUT test in Kconfig

 - Fix noisy "No such file or directory" message when
   KBUILD_BUILD_VERSION is passed

 - Include rust/ in source tarballs

 - Fix missing FORCE for ARCH=nios2 builds

* tag 'kbuild-fixes-v6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  nios2: add FORCE for vmlinuz.gz
  scripts: add rust in scripts/Makefile.package
  kbuild: fix "cat: .version: No such file or directory"
  init/Kconfig: fix CC_HAS_ASM_GOTO_TIED_OUTPUT test with dash

Add FORCE to placate a warning from make:

arch/nios2/boot/Makefile:24: FORCE prerequisite is missing

Fixes: 2fc8483f ("nios2: Build infrastructure")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>

Pull nfsd fix from Chuck Lever:

 - Fix rare data corruption on READ operations

* tag 'nfsd-6.1-6' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: Fix reads with a non-zero offset that don't end on a page boundary

Pull power supply fixes from Sebastian Reichel:

 - rk817: Two error handling fixes

 - ip5xxx: fix inter overflow in current calculation

 - ab8500: fix thermal zone probing

* tag 'for-v6.1-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply:
  power: supply: ab8500: Defer thermal zone probe
  power: supply: ip5xxx: Fix integer overflow in current_now calculation
  power: supply: rk817: Change rk817_chg_cur_to_reg to int
  power: supply: rk817: check correct variable