When switching to the new iovec accessors, a negation got subtly
dropped, leading to 9p being remarkably broken (here with kvmtool):

[    7.430941] VFS: Mounted root (9p filesystem) on device 0:15.
[    7.432080] devtmpfs: mounted
[    7.432717] Freeing unused kernel memory: 1344K
[    7.433658] Run /virt/init as init process
  Warning: unable to translate guest address 0x7e00902ff000 to host
  Warning: unable to translate guest address 0x7e00902fefc0 to host
  Warning: unable to translate guest address 0x7e00902ff000 to host
  Warning: unable to translate guest address 0x7e008febef80 to host
  Warning: unable to translate guest address 0x7e008febf000 to host
  Warning: unable to translate guest address 0x7e008febef00 to host
  Warning: unable to translate guest address 0x7e008febf000 to host
[    7.436376] Kernel panic - not syncing: Requested init /virt/init failed (error -8).
[    7.437554] CPU: 29 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc8-02267-g00e23707442a #291
[    7.439006] Hardware name: linux,dummy-virt (DT)
[    7.439902] Call trace:
[    7.440387]  dump_backtrace+0x0/0x148
[    7.441104]  show_stack+0x14/0x20
[    7.441768]  dump_stack+0x90/0xb4
[    7.442425]  panic+0x120/0x27c
[    7.443036]  kernel_init+0xa4/0x100
[    7.443725]  ret_from_fork+0x10/0x18
[    7.444444] SMP: stopping secondary CPUs
[    7.445391] Kernel Offset: disabled
[    7.446169] CPU features: 0x0,23000438
[    7.446974] Memory Limit: none
[    7.447645] ---[ end Kernel panic - not syncing: Requested init /virt/init failed (error -8). ]---

Restoring the missing "!" brings the guest back to life.

Fixes: 00e23707

 ("iov_iter: Use accessor function")
Reported-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

sunrpc patches from nfs tree conflict with calling conventions change done
in iov_iter work.  Trivial fixup...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

backmerge to do fixup of iov_iter_kvec() conflict

Send probes to all the unprobed fileservers in a fileserver list on all
addresses simultaneously in an attempt to find out the fastest route whilst
not getting stuck for 20s on any server or address that we don't get a
reply from.

This alleviates the problem whereby attempting to access a new server can
take a long time because the rotation algorithm ends up rotating through
all servers and addresses until it finds one that responds.

Signed-off-by: David Howells <dhowells@redhat.com>

In some circumstances, the callback interest pointer is NULL, so in such a
case we can't dereference it when checking to see if the callback is
broken.  This causes an oops in some circumstances.

Fix this by replacing the function that worked out the aggregate break
counter with one that actually does the comparison, and then make that
return true (ie. broken) if there is no callback interest as yet (ie. the
pointer is NULL).

Fixes: 68251f0a

 ("afs: Fix whole-volume callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>

Eliminate the address pointer from the address list cursor as it's
redundant (ac->addrs[ac->index] can be used to find the same address) and
address lists must be replaced rather than being rearranged, so is of
limited value.

Signed-off-by: David Howells <dhowells@redhat.com>

Provide an option to allow the file or volume location server cursor to be
dumped if the rotation routine falls off the end without managing to
contact a server.

Signed-off-by: David Howells <dhowells@redhat.com>

Implement support for talking to YFS-variant fileservers in the cache
manager and the filesystem client.  These implement upgraded services on
the same port as their AFS services.

YFS fileservers provide expanded capabilities over AFS.

Signed-off-by: David Howells <dhowells@redhat.com>

Expand fields in various data structures to support the expanded
information that YFS is capable of returning.

Signed-off-by: David Howells <dhowells@redhat.com>

Get the target vnode in afs_rmdir() and validate it before we attempt the
deletion, The vnode pointer will be passed through to the delivery function
in a later patch so that the delivery function can mark it deleted.

Signed-off-by: David Howells <dhowells@redhat.com>

Calculate the callback expiration time at the point of operation reply
delivery, using the reply time queried from AF_RXRPC on that call as a
base.

Signed-off-by: David Howells <dhowells@redhat.com>

The FS.FetchStatus reply delivery function was updating inode of the
directory in which a lookup had been done with the status of the looked up
file.  This corrupts some of the directory state.

Fixes: 5cf9dd55

 ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>

Implement the YFS cache manager service which gives extra capabilities on
top of AFS.  This is done by listening for an additional service on the
same port and indicating that anyone requesting an upgrade should be
upgraded to the YFS port.

Signed-off-by: David Howells <dhowells@redhat.com>

Remove unnecessary details of a broken callback, such as version, expiry
and type, from the afs_callback_break struct as they're not actually used
and make the list take more memory.

Signed-off-by: David Howells <dhowells@redhat.com>

Call the function to commit the status on a new file, dir or symlink so
that the access rights for the caller's key are cached for that object.

Without this, the next access to the file will cause a FetchStatus
operation to be emitted to retrieve the access rights.

Signed-off-by: David Howells <dhowells@redhat.com>

Increase the sizes of the volume ID to 64 bits and the vnode ID (inode
number equivalent) to 96 bits to allow the support of YFS.

This requires the iget comparator to check the vnode->fid rather than i_ino
and i_generation as i_ino is not sufficiently capacious.  It also requires
this data to be placed into the vnode cache key for fscache.

For the moment, just discard the top 32 bits of the vnode ID when returning
it though stat.

Signed-off-by: David Howells <dhowells@redhat.com>

When writing a new page, clear space in the page rather than attempting to
load it from the server if the space is beyond the EOF.

Signed-off-by: David Howells <dhowells@redhat.com>

Add a couple of tracepoints to log the production of I/O errors within the AFS
filesystem.

Signed-off-by: David Howells <dhowells@redhat.com>

Fix afs_deliver_to_call() to handle -EIO being returned by the operation
delivery function, indicating that the call found itself in the wrong
state, by printing an error and aborting the call.

Currently, an assertion failure will occur.  This can happen, say, if the
delivery function falls off the end without calling afs_extract_data() with
the want_more parameter set to false to collect the end of the Rx phase of
a call.

The assertion failure looks like:

	AFS: Assertion failed
	4 == 7 is false
	0x4 == 0x7 is false
	------------[ cut here ]------------
	kernel BUG at fs/afs/rxrpc.c:462!

and is matched in the trace buffer by a line like:

kworker/7:3-3226 [007] ...1 85158.030203: afs_io_error: c=0003be0c r=-5 CM_REPLY

Fixes: 98bf40cd

 ("afs: Protect call->state changes against signals")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>

Currently the TTL on VL server and address lists isn't set in all
circumstances and may be set to poor choices in others, since the TTL is
derived from the SRV/AFSDB DNS record if and when available.

Fix the TTL by limiting the range to a minimum and maximum from the current
time.  At some point these can be made into sysctl knobs.  Further, use the
TTL we obtained from the upcall to set the expiry on negative results too;
in future a mechanism can be added to force reloading of such data.

Signed-off-by: David Howells <dhowells@redhat.com>

Track VL servers as independent entities rather than lumping all their
addresses together into one set and implement server-level rotation by:

 (1) Add the concept of a VL server list, where each server has its own
     separate address list.  This code is similar to the FS server list.

 (2) Use the DNS resolver to retrieve a set of servers and their associated
     addresses, ports, preference and weight ratings.

 (3) In the case of a legacy DNS resolver or an address list given directly
     through /proc/net/afs/cells, create a list containing just a dummy
     server record and attach all the addresses to that.

 (4) Implement a simple rotation policy, for the moment ignoring the
     priorities and weights assigned to the servers.

 (5) Show the address list through /proc/net/afs/<cell>/vlservers.  This
     also displays the source and status of the data as indicated by the
     upcall.

Signed-off-by: David Howells <dhowells@redhat.com>

Improve the error handling in FS server rotation by:

 (1) Cache the latest useful error value for the fs operation as a whole in
     struct afs_fs_cursor separately from the error cached in the
     afs_addr_cursor struct.  The one in the address cursor gets clobbered
     occasionally.  Copy over the error to the fs operation only when it's
     something we'd be interested in passing to userspace.

 (2) Make it so that EDESTADDRREQ is the default that is seen only if no
     addresses are available to be accessed.

 (3) When calling utility functions, such as checking a volume status or
     probing a fileserver, don't let a successful result clobber the cached
     error in the cursor; instead, stash the result in a temporary variable
     until it has been assessed.

 (4) Don't return ETIMEDOUT or ETIME if a better error, such as
     ENETUNREACH, is already cached.

 (5) On leaving the rotation loop, turn any remote abort code into a more
     useful error than ECONNABORTED.

Fixes: d2ddc776

 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>

afs_extract_data sets up a temporary iov_iter and passes it to AF_RXRPC
each time it is called to describe the remaining buffer to be filled.

Instead:

 (1) Put an iterator in the afs_call struct.

 (2) Set the iterator for each marshalling stage to load data into the
     appropriate places.  A number of convenience functions are provided to
     this end (eg. afs_extract_to_buf()).

     This iterator is then passed to afs_extract_data().

 (3) Use the new ITER_DISCARD iterator to discard any excess data provided
     by FetchData.

Signed-off-by: David Howells <dhowells@redhat.com>

Include the site of detection of AFS protocol errors in trace lines to
better be able to determine what went wrong.

Signed-off-by: David Howells <dhowells@redhat.com>

Add a new iterator, ITER_DISCARD, that can only be used in READ mode and
just discards any data copied to it.

This is useful in a network filesystem for discarding any unwanted data
sent by a server.

Signed-off-by: David Howells <dhowells@redhat.com>

In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>

Use accessor functions to access an iterator's type and direction.  This
allows for the possibility of using some other method of determining the
type of iterator than if-chains with bitwise-AND conditions.

Signed-off-by: David Howells <dhowells@redhat.com>

Remove the undefinition of READ and WRITE because these constants may be
used elsewhere in subsequently included header files, thus breaking them.

These constants don't actually appear to be used in the driver, so the
undefinition seems pointless.

Fixes: 4562236b

 ("drm/amd/dc: Add dc display driver (v2)")
Signed-off-by: David Howells <dhowells@redhat.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We no longer need to worry about whether or not the entry is hashed in
order to figure out if the contents are valid. We only care whether or
not the refcount is non-zero.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

The filehandle has a length which is defined as a 32-bit
"unsigned integer".  Change sign of the length appropriately.

Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

net/sched/cls_api.c has overlapping changes to a call to
nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL
to the 5th argument, and another (from 'net-next') added cb->extack
instead of NULL to the 6th argument.

net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to
code which moved (to mr_table_dump)) in 'net-next'.  Thanks to David
Ahern for the heads up.

Signed-off-by: David S. Miller <davem@davemloft.net>

This reverts commit 6fe94878

.

It is causing more serious regressions than the RCU warning
it is fixing.

Signed-off-by: David S. Miller <davem@davemloft.net>

There is no need to have the 'struct rocker_desc_info *desc_info'
variable static since new value always be assigned before use it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

David writes:
  "Networking

   1) Fix gro_cells leak in xfrm layer, from Li RongQing.

   2) BPF selftests change RLIMIT_MEMLOCK blindly, don't do that.  From
      Eric Dumazet.

   3) AF_XDP calls synchronize_net() under RCU lock, fix from Björn
      Töpel.

   4) Out of bounds packet access in _decode_session6(), from Alexei
      Starovoitov.

   5) Several ethtool bugs, where we copy a struct into the kernel twice
      and our validations of the values in the first copy can be
      invalidated by the second copy due to asynchronous updates to the
      memory by the user.  From Wenwen Wang.

   6) Missing netlink attribute validation in cls_api, from Davide
      Caratti.

   7) LLC SAP sockets neet to be SOCK_RCU FREE, from Cong Wang.

   8) rxrpc operates on wrong kvec, from Yue Haibing.

   9) A regression was introduced by the disassosciation of route
      neighbour references in rt6_probe(), causing probe for
      neighbourless routes to not be properly rate limited.  Fix from
      Sabrina Dubroca.

   10) Unsafe RCU locking in tipc, from Tung Nguyen.

   11) Use after free in inet6_mc_check(), from Eric Dumazet.

   12) PMTU from icmp packets should update the SCTP transport pathmtu,
       from Xin Long.

   13) Missing peer put on error in rxrpc, from David Howells.

   14) Fix pedit in nfp driver, from Pieter Jansen van Vuuren.

   15) Fix overflowing shift statement in qla3xxx driver, from Nathan
       Chancellor.

   16) Fix Spectre v1 in ptp code, from Gustavo A. R. Silva.

   17) udp6_unicast_rcv_skb() interprets udpv6_queue_rcv_skb() return
       value in an inverted manner, fix from Paolo Abeni.

   18) Fix missed unresolved entries in ipmr dumps, from Nikolay
       Aleksandrov.

   19) Fix NAPI handling under high load, we can completely miss events
       when NAPI has to loop more than one time in a cycle.  From Heiner
       Kallweit."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (49 commits)
  ip6_tunnel: Fix encapsulation layout
  tipc: fix info leak from kernel tipc_event
  net: socket: fix a missing-check bug
  net: sched: Fix for duplicate class dump
  r8169: fix NAPI handling under high load
  net: ipmr: fix unresolved entry dumps
  net: mscc: ocelot: Fix comment in ocelot_vlant_wait_for_completion()
  sctp: fix the data size calculation in sctp_data_size
  virtio_net: avoid using netif_tx_disable() for serializing tx routine
  udp6: fix encap return code for resubmitting
  mlxsw: core: Fix use-after-free when flashing firmware during init
  sctp: not free the new asoc when sctp_wait_for_connect returns err
  sctp: fix race on sctp_id2asoc
  r8169: re-enable MSI-X on RTL8168g
  net: bpfilter: use get_pid_task instead of pid_task
  ptp: fix Spectre v1 vulnerability
  net: qla3xxx: Remove overflowing shift statement
  geneve, vxlan: Don't set exceptions if skb->len < mtu
  geneve, vxlan: Don't check skb_dst() twice
  sctp: get pr_assoc and pr_stream all status with SCTP_PR_SCTP_ALL instead
  ...

David writes:
  "Sparc fixes:

   The main bit here is fixing how fallback system calls are handled in
   the sparc vDSO.

   Unfortunately, I fat fingered the commit and some perf debugging
   hacks slipped into the vDSO fix, which I revert in the very next
   commit."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: Revert unintended perf changes.
  sparc: vDSO: Silence an uninitialized variable warning
  sparc: Fix syscall fallback bugs in VDSO.

Dave writes:
  "drm fixes for 4.19 final

   Just a last set of misc core fixes for final.

   4 fixes, one use after free, one fb integration fix, one EDID fix,
   and one laptop panel quirk,"

* tag 'drm-fixes-2018-10-19' of git://anongit.freedesktop.org/drm/drm:
  drm/edid: VSDB yCBCr420 Deep Color mode bit definitions
  drm: fix use of freed memory in drm_mode_setcrtc
  drm: fb-helper: Reject all pixel format changing requests
  drm/edid: Add 6 bpc quirk for BOE panel in HP Pavilion 15-n233sl

Doug writes:
  "Really final for-rc pull request for 4.19

   Ok, so last week I thought we had sent our final pull request for
   4.19.  Well, wouldn't ya know someone went and found a couple Spectre
   v1 fixes were needed :-/.  So, a couple *very* small specter patches
   for this (hopefully) final -rc week."

* tag 'for-gkh' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/ucma: Fix Spectre v1 vulnerability
  IB/ucm: Fix Spectre v1 vulnerability