When the user turns off all minor versions of NFSv4, that should be
equivalent to turning off NFSv4 support, so a mount attempt using NFSv4
should get RPC_PROG_MISMATCH, not NFSERR_MINOR_VERS_MISMATCH.

Allow the user to use either '4.0' or '4' to enable or disable minor
version 0.  Other minor versions are still enabled or disabled using the
'4.x' format.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

NFSv4 requires a transport "that is specified to avoid network
congestion" (RFC 7530, section 3.1, paragraph 2).  In practical terms,
that means that you should not run NFSv4 over UDP. The server has never
enforced that requirement, however.

This patchset fixes this by adding a new flag to the svc_version that
states that it has these transport requirements. With that, we can check
that the transport has XPT_CONG_CTRL set before processing an RPC. If it
doesn't we reject it with RPC_PROG_MISMATCH.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

NFSv4 requires a transport protocol with congestion control in most
cases.

On an IP network, that means that NFSv4 over UDP should be forbidden.

The situation with RDMA is a bit more nuanced, but most RDMA transports
are suitable for this. For now, we assume that all RDMA transports are
suitable, but we may need to revise that at some point.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

It's just simpler to read this way, IMO. Also, no need to explicitly
set vs_hidden to false in the nfsacl ones.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

dprintk already provides a KERN_* prefix; this KERN_INFO just shows up
as some odd characters in the output.

Simplify the message a bit while we're there.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Both the NFS protocols and the Linux VFS use a setattr operation with a
bitmap of attributes to set to set various file attributes including the
file size and the uid/gid.

The Linux syscalls never mix size updates with unrelated updates like
the uid/gid, and some file systems like XFS and GFS2 rely on the fact
that truncates don't update random other attributes, and many other file
systems handle the case but do not update the other attributes in the
same transaction.  NFSD on the other hand passes the attributes it gets
on the wire more or less directly through to the VFS, leading to updates
the file systems don't expect.  XFS at least has an assert on the
allowed attributes, which caught an unusual NFS client setting the size
and group at the same time.

To handle this issue properly this splits the notify_change call in
nfsd_setattr into two separate ones.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Tested-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Simplify exit paths, size_change use.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

After tightening the OP_LOCKT reply size estimate, we can get warnings
like:

[11512.783519] RPC request reserved 124 but used 152
[11512.813624] RPC request reserved 108 but used 136
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

NFSD usess PAGE_SIZE as the reply size estimate for RPCs which don't
support op_rsize_bop(), A PAGE_SIZE (4096) is larger than many real
response sizes, eg, access (op_encode_hdr_size + 2), seek
(op_encode_hdr_size + 3).

This patch just adds op_rsize_bop() for all RPCs getting response size.

An overestimate is generally safe but the tighter estimates are probably
better.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The callback tag is NULL, and hdr->nops is unused too right now, but.
But if we were to ever test with a nonzero callback tag, nops will get a
bad value.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The rpccred gotten from rpc_lookup_machine_cred() should be put when
state is shutdown.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Tigran Mkrtchyan's new pynfs testcases for zero length principals fail:

SATT16   st_setattr.testEmptyPrincipal                            : FAILURE
           Setting empty owner should return NFS4ERR_INVAL,
           instead got NFS4ERR_BADOWNER
SATT17   st_setattr.testEmptyGroupPrincipal                       : FAILURE
           Setting empty owner_group should return NFS4ERR_INVAL,
           instead got NFS4ERR_BADOWNER

This patch checks the principal and returns nfserr_inval directly.  It
could check after decoding in nfs4xdr.c, but it's simpler to do it in
nfsd_map_xxxx.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This patch incorrectly attempted nested mnt_want_write, and incorrectly
disabled nfsd's owner override for truncate.  We'll fix those problems
and make another attempt soon, for the moment I think the safest is to
revert.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

When the first time pynfs runs after rpc/nfsd startup, always get the warning,

"Got error: Connection closed"

I found the problem is caused by,
1. A new startup of nfsd, rpc.mountd, etc,
2. A rpc request from client (pynfs test, or normal mounting),
3. An ip_map cache is created but invalid, so upcall to rpc.mountd,
4. rpc.mountd process the ip_map upcall, before write the valid data to nfsd,
   do auth_reload(), and check_useipaddr(),
5. For the first time, old_use_ipaddr = -1, it causes rpc.mountd do write_flush    that doing cache_clean,
6. The ip_map cache will be treat as expired and clean,
7. When rpc.mountd write the valid data to nfsd, a new ip_map is created
   and updated, the cache_check of old ip_map(doing the upcall) will
   return -ETIMEDOUT.
8. RPC layer return SVC_CLOSE and close the xprt after commit 4d712ef1
   "svcauth_gss: Close connection when dropping an incoming message"

NeilBrown suggest in another email,

"If CACHE_VALID is not set, then there is no data in the cache item,
 so there is nothing to expire. So it would be nice if cache items that
 don't have CACHE_VALID are never treated as expired."

v3, change the order of the two patches
v2, change the checking of CACHE_PENDING to CACHE_VALID
Reviewed-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

User always free the cache_detail after sunrpc_destroy_cache_detail(),
so, it must cleanup up entries that left in the cache_detail,
otherwise, NULL reference may be caused when using the left entries.

Also, NeriBrown suggests "write a stand-alone cache_purge()."

v3, move the cache_fresh_unlocked() out of write lock,
v2, a stand-alone cache_purge(), not only for sunrpc_destroy_cache_detail
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Reviewed-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

svcrdma calls svc_xprt_put() in its completion handlers, which
currently run in IRQ context.

However, svc_xprt_put() is meant to be invoked in process context,
not in IRQ context. After the last transport reference is gone, it
directly calls a transport release function that expects to run in
process context.

Change the CQ polling modes to IB_POLL_WORKQUEUE so that svcrdma
invokes svc_xprt_put() only in process context. As an added benefit,
bottom half-disabled spin locking can be eliminated from I/O paths.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Clean up: The free list and the dto_q list fields are never used at
the same time. Reduce the size of struct svc_rdma_op_ctxt by
combining these fields.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Clean up. Commit be99bb11 ("svcrdma: Use new CQ API for
RPC-over-RDMA server send CQs") removed code that used the sc_dto_q
field, but neglected to remove sc_dto_q at the same time.

Fixes: be99bb11 ("svcrdma: Use new CQ API for RPC-over- ...")
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Replace C structure-based XDR decoding with pointer arithmetic.
Pointer arithmetic is considered more portable.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Replace C structure-based XDR decoding with pointer arithmetic.
Pointer arithmetic is considered more portable.

Rename the "decode" functions. Nothing is decoded here, they
perform only transport header sanity checking. Use existing XDR
naming conventions to help readability.

Straight-line the hot path:
 - relocate the dprintk call sites out of line
 - remove unnecessary byte-swapping
 - reduce count of conditional branches

Deprecate RDMA_MSGP. It's not properly spec'd by RFC5666, and
therefore never used by any V1 client.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Replace C structure-based XDR decoding with pointer arithmetic.
Pointer arithmetic is considered more portable, and is used
throughout the kernel's existing XDR encoders. The gcc optimizer
generates similar assembler code either way.

Byte-swapping before a memory store on x86 typically results in an
instruction pipeline stall. Avoid byte-swapping when encoding a new
header.

svcrdma currently doesn't alter a connection's credit grant value
after the connection has been accepted, so it is effectively a
constant. Cache the byte-swapped value in a separate field.

Christoph suggested pulling the header encoding logic into the only
function that uses it.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Commit 5fdca653 ("svcrdma: Renovate sendto chunk list parsing")
missed a spot. svc_rdma_xdr_get_reply_hdr_len() also assumes the
Write list has only one Write chunk. There's no harm in making this
code more general.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

If you change the set of filesystems that are exported, then
the contents of various directories in the NFSv4 pseudo-root
is likely to change.  However the change-id of those
directories is currently tied to the underlying directory,
so the client may not see the changes in a timely fashion.

This patch changes the change-id number to be derived from the
"flush_time" of the export cache.  Whenever any changes are
made to the set of exported filesystems, this flush_time is
updated.  The result is that clients see changes to the set
of exported filesystems much more quickly, often immediately.
Signed-off-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Pull irq fixes from Thomas Gleixner:

 - Prevent double activation of interrupt lines, which causes problems
   on certain interrupt controllers

 - Handle the fallout of the above because x86 (ab)uses the activation
   function to reconfigure interrupts under the hood.

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/irq: Make irq activate operations symmetric
  irqdomain: Avoid activating interrupts more than once

Pull KVM fix from Radim Krčmář:
 "Fix a regression that prevented migration between hosts with different
  XSAVE features even if the missing features were not used by the guest
  (for stable)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: do not save guest-unsupported XSAVE state

Pull char/misc driver fixes from Greg KH:
 "Here are two bugfixes that resolve some reported issues. One in the
  firmware loader, that should fix the much-reported problem of crashes
  with it. The other is a hyperv fix for a reported regression.

  Both have been in linux-next for a week or so with no reported issues"

* tag 'char-misc-4.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()
  firmware: fix NULL pointer dereference in __fw_load_abort()

Pull staging/IIO fixes from Greg KH:
 "Here are a few small IIO and one staging driver fix for 4.10-rc7. They
  fix some reported issues with the drivers.

  All of them have been in linux-next for a week or so with no reported
  issues"

* tag 'staging-4.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: greybus: timesync: validate platform state callback
  iio: dht11: Use usleep_range instead of msleep for start signal
  iio: adc: palmas_gpadc: retrieve a valid iio_dev in suspend/resume
  iio: health: max30100: fixed parenthesis around FIFO count check
  iio: health: afe4404: retrieve a valid iio_dev in suspend/resume
  iio: health: afe4403: retrieve a valid iio_dev in suspend/resume

Pull USB fixes from Greg KH:
 "Here are some small USB fixes for some reported issues, and the usual
  number of new device ids for 4.10-rc7.

  All of these, except the last new device id, have been in linux-next
  for a while with no reported issues"

* tag 'usb-4.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: serial: pl2303: add ATEN device ID
  usb: gadget: f_fs: Assorted buffer overflow checks.
  USB: Add quirk for WORLDE easykey.25 MIDI keyboard
  usb: musb: Fix external abort on non-linefetch for musb_irq_work()
  usb: musb: Fix host mode error -71 regression
  USB: serial: option: add device ID for HP lt2523 (Novatel E371)
  USB: serial: qcserial: add Dell DW5570 QDL

Pull SCSI fix from James Bottomley:
 "A single fix this time: a fix for a virtqueue removal bug which only
  appears to affect S390, but which results in the queue hanging forever
  thus causing the machine to fail shutdown"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: virtio_scsi: Reject commands when virtqueue is broken

Pull virtio/vhost fixes from Michael S. Tsirkin:
 "Last minute fixes:

   - ARM DMA fix revert

   - vhost endian-ness fix

   - MAINTAINERS: email address change for Amit"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  MAINTAINERS: update email address for Amit Shah
  vhost: fix initialization for vq->is_le
  Revert "vring: Force use of DMA API for ARM-based systems with legacy devices"

Pull VFIO fix from Alex Williamson:
 "Fix an error path in SPAPR IOMMU backend (Alexey Kardashevskiy)"

* tag 'vfio-v4.10-rc7' of git://github.com/awilliam/linux-vfio:
  vfio/spapr: Fix missing mutex unlock when creating a window

Merge fixes from Andrew Morton:
 "8 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, fs: check for fatal signals in do_generic_file_read()
  fs: break out of iomap_file_buffered_write on fatal signals
  base/memory, hotplug: fix a kernel oops in show_valid_zones()
  mm/memory_hotplug.c: check start_pfn in test_pages_in_a_zone()
  jump label: pass kbuild_cflags when checking for asm goto support
  shmem: fix sleeping from atomic context
  kasan: respect /proc/sys/kernel/traceoff_on_warning
  zswap: disable changing params if init fails

do_generic_file_read() can be told to perform a large request from
userspace.  If the system is under OOM and the reading task is the OOM
victim then it has an access to memory reserves and finishing the full
request can lead to the full memory depletion which is dangerous.  Make
sure we rather go with a short read and allow the killed task to
terminate.

Link: http://lkml.kernel.org/r/20170201092706.9966-3-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Tetsuo has noticed that an OOM stress test which performs large write
requests can cause the full memory reserves depletion.  He has tracked
this down to the following path

	__alloc_pages_nodemask+0x436/0x4d0
	alloc_pages_current+0x97/0x1b0
	__page_cache_alloc+0x15d/0x1a0          mm/filemap.c:728
	pagecache_get_page+0x5a/0x2b0           mm/filemap.c:1331
	grab_cache_page_write_begin+0x23/0x40   mm/filemap.c:2773
	iomap_write_begin+0x50/0xd0             fs/iomap.c:118
	iomap_write_actor+0xb5/0x1a0            fs/iomap.c:190
	? iomap_write_end+0x80/0x80             fs/iomap.c:150
	iomap_apply+0xb3/0x130                  fs/iomap.c:79
	iomap_file_buffered_write+0x68/0xa0     fs/iomap.c:243
	? iomap_write_end+0x80/0x80
	xfs_file_buffered_aio_write+0x132/0x390 [xfs]
	? remove_wait_queue+0x59/0x60
	xfs_file_write_iter+0x90/0x130 [xfs]
	__vfs_write+0xe5/0x140
	vfs_write+0xc7/0x1f0
	? syscall_trace_enter+0x1d0/0x380
	SyS_write+0x58/0xc0
	do_syscall_64+0x6c/0x200
	entry_SYSCALL64_slow_path+0x25/0x25

the oom victim has access to all memory reserves to make a forward
progress to exit easier.  But iomap_file_buffered_write and other
callers of iomap_apply loop to complete the full request.  We need to
check for fatal signals and back off with a short write instead.

As the iomap_apply delegates all the work down to the actor we have to
hook into those.  All callers that work with the page cache are calling
iomap_write_begin so we will check for signals there.  dax_iomap_actor
has to handle the situation explicitly because it copies data to the
userspace directly.  Other callers like iomap_page_mkwrite work on a
single page or iomap_fiemap_actor do not allocate memory based on the
given len.

Fixes: 68a9f5e7 ("xfs: implement iomap based buffered write path")
Link: http://lkml.kernel.org/r/20170201092706.9966-2-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Reported-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>	[4.8+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Reading a sysfs "memoryN/valid_zones" file leads to the following oops
when the first page of a range is not backed by struct page.
show_valid_zones() assumes that 'start_pfn' is always valid for
page_zone().

 BUG: unable to handle kernel paging request at ffffea017a000000
 IP: show_valid_zones+0x6f/0x160

This issue may happen on x86-64 systems with 64GiB or more memory since
their memory block size is bumped up to 2GiB.  [1] An example of such
systems is desribed below.  0x3240000000 is only aligned by 1GiB and
this memory block starts from 0x3200000000, which is not backed by
struct page.

 BIOS-e820: [mem 0x0000003240000000-0x000000603fffffff] usable

Since test_pages_in_a_zone() already checks holes, fix this issue by
extending this function to return 'valid_start' and 'valid_end' for a
given range.  show_valid_zones() then proceeds with the valid range.

[1] 'Commit bdee237c ("x86: mm: Use 2GB memory block size on
    large-memory x86-64 systems")'

Link: http://lkml.kernel.org/r/20170127222149.30893-3-toshi.kani@hpe.comSigned-off-by: NToshi Kani <toshi.kani@hpe.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Zhang Zhen <zhenzhang.zhang@huawei.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>	[4.4+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "fix a kernel oops when reading sysfs valid_zones", v2.

A sysfs memory file is created for each 2GiB memory block on x86-64 when
the system has 64GiB or more memory.  [1] When the start address of a
memory block is not backed by struct page, i.e.  a memory range is not
aligned by 2GiB, reading its 'valid_zones' attribute file leads to a
kernel oops.  This issue was observed on multiple x86-64 systems with
more than 64GiB of memory.  This patch-set fixes this issue.

Patch 1 first fixes an issue in test_pages_in_a_zone(), which does not
test the start section.

Patch 2 then fixes the kernel oops by extending test_pages_in_a_zone()
to return valid [start, end).

Note for stable kernels: The memory block size change was made by commit
bdee237c ("x86: mm: Use 2GB memory block size on large-memory x86-64
systems"), which was accepted to 3.9.  However, this patch-set depends
on (and fixes) the change to test_pages_in_a_zone() made by commit
5f0f2887 ("mm/memory_hotplug.c: check for missing sections in
test_pages_in_a_zone()"), which was accepted to 4.4.

So, I recommend that we backport it up to 4.4.

[1] 'Commit bdee237c ("x86: mm: Use 2GB memory block size on
    large-memory x86-64 systems")'

This patch (of 2):

test_pages_in_a_zone() does not check 'start_pfn' when it is aligned by
section since 'sec_end_pfn' is set equal to 'pfn'.  Since this function
is called for testing the range of a sysfs memory file, 'start_pfn' is
always aligned by section.

Fix it by properly setting 'sec_end_pfn' to the next section pfn.

Also make sure that this function returns 1 only when the range belongs
to a zone.

Link: http://lkml.kernel.org/r/20170127222149.30893-2-toshi.kani@hpe.comSigned-off-by: NToshi Kani <toshi.kani@hpe.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Greg KH <greg@kroah.com>
Cc: <stable@vger.kernel.org>	[4.4+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>