The user interface exposes a new capability KVM_CAP_PPC_IRQ_XIVE to
let QEMU connect the vCPU presenters to the XIVE KVM device if
required. The capability is not advertised for now as the full support
for the XIVE native exploitation mode is not yet available. When this
is case, the capability will be advertised on PowerNV Hypervisors
only. Nested guests (pseries KVM Hypervisor) are not supported.

Internally, the interface to the new KVM device is protected with a
new interrupt mode: KVMPPC_IRQ_XIVE.
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

This is the basic framework for the new KVM device supporting the XIVE
native exploitation mode. The user interface exposes a new KVM device
to be created by QEMU, only available when running on a L0 hypervisor.
Support for nested guests is not available yet.

The XIVE device reuses the device structure of the XICS-on-XIVE device
as they have a lot in common. That could possibly change in the future
if the need arise.
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

I do not see any consistency about headers_install of <linux/kvm_para.h>
and <asm/kvm_para.h>.

According to my analysis of Linux 5.1-rc1, there are 3 groups:

 [1] Both <linux/kvm_para.h> and <asm/kvm_para.h> are exported

    alpha, arm, hexagon, mips, powerpc, s390, sparc, x86

 [2] <asm/kvm_para.h> is exported, but <linux/kvm_para.h> is not

    arc, arm64, c6x, h8300, ia64, m68k, microblaze, nios2, openrisc,
    parisc, sh, unicore32, xtensa

 [3] Neither <linux/kvm_para.h> nor <asm/kvm_para.h> is exported

    csky, nds32, riscv

This does not match to the actual KVM support. At least, [2] is
half-baked.

Nor do arch maintainers look like they care about this. For example,
commit 0add5371 ("microblaze: Add missing kvm_para.h to Kbuild")
exported <asm/kvm_para.h> to user-space in order to fix an in-kernel
build error.

We have two ways to make this consistent:

 [A] export both <linux/kvm_para.h> and <asm/kvm_para.h> for all
     architectures, irrespective of the KVM support

 [B] Match the header export of <linux/kvm_para.h> and <asm/kvm_para.h>
     to the KVM support

My first attempt was [A] because the code looks cleaner, but Paolo
suggested [B].

So, this commit goes with [B].

For most architectures, <asm/kvm_para.h> was moved to the kernel-space.
I changed include/uapi/linux/Kbuild so that it checks generated
asm/kvm_para.h as well as check-in ones.

After this commit, there will be two groups:

 [1] Both <linux/kvm_para.h> and <asm/kvm_para.h> are exported

    arm, arm64, mips, powerpc, s390, x86

 [2] Neither <linux/kvm_para.h> nor <asm/kvm_para.h> is exported

    alpha, arc, c6x, csky, h8300, hexagon, ia64, m68k, microblaze,
    nds32, nios2, openrisc, parisc, riscv, sh, sparc, unicore32, xtensa
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Large enterprise clients often run applications out of networked file
systems where the IT mandated layout of project volumes can end up
leading to paths that are longer than 128 characters.  Bumping this up
to the next order of two solves this problem in all but the most
egregious case while still fitting into a 512b slab.

[oleg@redhat.com: update comment, per Kees]
Link: http://lkml.kernel.org/r/20181112160956.GA28472@redhat.comSigned-off-by: NOleg Nesterov <oleg@redhat.com>
Reported-by: NBen Woodard <woodard@redhat.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NKees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add an autofs file system mount option that can be used to provide a
generic indicator to applications that the mount entry should be ignored
when displaying mount information.

In other OSes that provide autofs and that provide a mount list to user
space based on the kernel mount list a no-op mount option ("ignore" is
the one use on the most common OS) is allowed so that autofs file system
users can optionally use it.

The idea is that it be used by user space programs to exclude autofs
mounts from consideration when reading the mounts list.

Prior to the change to link /etc/mtab to /proc/self/mounts all I needed
to do to achieve this was to use mount(2) and not update the mtab but
now that no longer works.

I know the symlinking happened a long time ago and I considered doing
this then but, at the time I couldn't remember the commonly used option
name and thought persuading the various utility maintainers would be too
hard.

But now I have a RHEL request to do this for compatibility for a widely
used product so I want to go ahead with it and try and enlist the help
of some utility package maintainers.

Clearly, without the option nothing can be done so it's at least a
start.

Link: http://lkml.kernel.org/r/154725123970.11260.6113771566924907275.stgit@pluto-themaw-netSigned-off-by: NIan Kent <raven@themaw.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

<linux/kernel.h> tends to be cluttered because we often put various sort
of unrelated stuff in it.  So, we have split out a sensible chunk of
code into a separate header from time to time.

This commit splits out the *_MAX and *_MIN defines.

The standard header <limits.h> contains various MAX, MIN constants
including numerial limits.  [1]

I think it makes sense to move in-kernel MAX, MIN constants into
include/linux/limits.h.

We already have include/uapi/linux/limits.h to contain some user-space
constants.  I changed its include guard to _UAPI_LINUX_LIMITS_H.  This
change has no impact to the user-space because
scripts/headers_install.sh rips off the '_UAPI' prefix from the include
guards of exported headers.

[1] http://pubs.opengroup.org/onlinepubs/009604499/basedefs/limits.h.html

Link: http://lkml.kernel.org/r/1549156242-20806-2-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Cc: Alex Elder <elder@linaro.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is basically a direct port of bfe4037e, which implements a
one-shot poll command through aio. Description below is based on that
commit as well. However, instead of adding a POLL command and relying
on io_cancel(2) to remove it, we mimic the epoll(2) interface of
having a command to add a poll notification, IORING_OP_POLL_ADD,
and one to remove it again, IORING_OP_POLL_REMOVE.

To poll for a file descriptor the application should submit an sqe of
type IORING_OP_POLL. It will poll the fd for the events specified in the
poll_events field.

Unlike poll or epoll without EPOLLONESHOT this interface always works in
one shot mode, that is once the sqe is completed, it will have to be
resubmitted.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Based-on-code-from: Christoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Android uses ashmem for sharing memory regions.  We are looking forward
to migrating all usecases of ashmem to memfd so that we can possibly
remove the ashmem driver in the future from staging while also
benefiting from using memfd and contributing to it.  Note staging
drivers are also not ABI and generally can be removed at anytime.

One of the main usecases Android has is the ability to create a region
and mmap it as writeable, then add protection against making any
"future" writes while keeping the existing already mmap'ed
writeable-region active.  This allows us to implement a usecase where
receivers of the shared memory buffer can get a read-only view, while
the sender continues to write to the buffer.  See CursorWindow
documentation in Android for more details:

  https://developer.android.com/reference/android/database/CursorWindow

This usecase cannot be implemented with the existing F_SEAL_WRITE seal.
To support the usecase, this patch adds a new F_SEAL_FUTURE_WRITE seal
which prevents any future mmap and write syscalls from succeeding while
keeping the existing mmap active.

A better way to do F_SEAL_FUTURE_WRITE seal was discussed [1] last week
where we don't need to modify core VFS structures to get the same
behavior of the seal.  This solves several side-effects pointed by Andy.
self-tests are provided in later patch to verify the expected semantics.

[1] https://lore.kernel.org/lkml/20181111173650.GA256781@google.com/

Thanks a lot to Andy for suggestions to improve code.

Link: http://lkml.kernel.org/r/20190112203816.85534-2-joel@joelfernandes.orgSigned-off-by: NJoel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: NJohn Stultz <john.stultz@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Marc-Andr Lureau <marcandre.lureau@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

PG_balloon was introduced to implement page migration/compaction for
pages inflated in virtio-balloon.  Nowadays, it is only a marker that a
page is part of virtio-balloon and therefore logically offline.

We also want to make use of this flag in other balloon drivers - for
inflated pages or when onlining a section but keeping some pages offline
(e.g.  used right now by XEN and Hyper-V via set_online_page_callback()).

We are going to expose this flag to dump tools like makedumpfile.  But
instead of exposing PG_balloon, let's generalize the concept of marking
pages as logically offline, so it can be reused for other purposes later
on.

Rename PG_balloon to PG_offline.  This is an indicator that the page is
logically offline, the content stale and that it should not be touched
(e.g.  a hypervisor would have to allocate backing storage in order for
the guest to dump an unused page).  We can then e.g.  exclude such pages
from dumps.

We replace and reuse KPF_BALLOON (23), as this shouldn't really harm
(and for now the semantics stay the same).  In following patches, we
will make use of this bit also in other balloon drivers.  While at it,
document PGTABLE.

[akpm@linux-foundation.org: fix comment text, per David]
Link: http://lkml.kernel.org/r/20181119101616.8901-3-david@redhat.comSigned-off-by: NDavid Hildenbrand <david@redhat.com>
Acked-by: NKonstantin Khlebnikov <koct9i@gmail.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NPankaj gupta <pagupta@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

By default IPv6 socket with IPV6_ROUTER_ALERT socket option set will
receive all IPv6 RA packets from all namespaces.
IPV6_ROUTER_ALERT_ISOLATE socket option restricts packets received by
the socket to be only from the socket's namespace.
Signed-off-by: NMaxim Martynov <maxim@arista.com>
Signed-off-by: NFrancesco Ruggeri <fruggeri@arista.com>
Reviewed-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add flag 'FWMARK' to enable use of firewall connmarks as tin selector.
The connmark (skbuff->mark) needs to be in the range 1->tin_cnt ie.
for diffserv3 the mark needs to be 1->3.

Background

Typically CAKE uses DSCP as the basis for tin selection.  DSCP values
are relatively easily changed as part of the egress path, usually with
iptables & the mangle table, ingress is more challenging.  CAKE is often
used on the WAN interface of a residential gateway where passthrough of
DSCP from the ISP is either missing or set to unhelpful values thus use
of ingress DSCP values for tin selection isn't helpful in that
environment.

An approach to solving the ingress tin selection problem is to use
CAKE's understanding of tc filters.  Naive tc filters could match on
source/destination port numbers and force tin selection that way, but
multiple filters don't scale particularly well as each filter must be
traversed whether it matches or not. e.g. a simple example to map 3
firewall marks to tins:

MAJOR=$( tc qdisc show dev $DEV | head -1 | awk '{print $3}' )
tc filter add dev $DEV parent $MAJOR protocol all handle 0x01 fw action skbedit priority ${MAJOR}1
tc filter add dev $DEV parent $MAJOR protocol all handle 0x02 fw action skbedit priority ${MAJOR}2
tc filter add dev $DEV parent $MAJOR protocol all handle 0x03 fw action skbedit priority ${MAJOR}3

Another option is to use eBPF cls_act with tc filters e.g.

MAJOR=$( tc qdisc show dev $DEV | head -1 | awk '{print $3}' )
tc filter add dev $DEV parent $MAJOR bpf da obj my-bpf-fwmark-to-class.o

This has the disadvantages of a) needing someone to write & maintain
the bpf program, b) a bpf toolchain to compile it and c) needing to
hardcode the major number in the bpf program so it matches the cake
instance (or forcing the cake instance to a particular major number)
since the major number cannot be passed to the bpf program via tc
command line.

As already hinted at by the previous examples, it would be helpful
to associate tins with something that survives the Internet path and
ideally allows tin selection on both egress and ingress.  Netfilter's
conntrack permits setting an identifying mark on a connection which
can also be restored to an ingress packet with tc action connmark e.g.

tc filter add dev eth0 parent ffff: protocol all prio 10 u32 \
	match u32 0 0 flowid 1:1 action connmark action mirred egress redirect dev ifb1

Since tc's connmark action has restored any connmark into skb->mark,
any of the previous solutions are based upon it and in one form or
another copy that mark to the skb->priority field where again CAKE
picks this up.

This change cuts out at least one of the (less intuitive &
non-scalable) middlemen and permit direct access to skb->mark.
Signed-off-by: NKevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
Signed-off-by: NToke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a new bpf helper BPF_FUNC_skb_ecn_set_ce
"int bpf_skb_ecn_set_ce(struct sk_buff *skb)". It is added to
BPF_PROG_TYPE_CGROUP_SKB typed bpf_prog which currently can
be attached to the ingress and egress path. The helper is needed
because his type of bpf_prog cannot modify the skb directly.

This helper is used to set the ECN field of ECN capable IP packets to ce
(congestion encountered) in the IPv6 or IPv4 header of the skb. It can be
used by a bpf_prog to manage egress or ingress network bandwdith limit
per cgroupv2 by inducing an ECN response in the TCP sender.
This works best when using DCTCP.
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

This enables an application to do IO, without ever entering the kernel.
By using the SQ ring to fill in new sqes and watching for completions
on the CQ ring, we can submit and reap IOs without doing a single system
call. The kernel side thread will poll for new submissions, and in case
of HIPRI/polled IO, it'll also poll for completions.

By default, we allow 1 second of active spinning. This can by changed
by passing in a different grace period at io_uring_register(2) time.
If the thread exceeds this idle time without having any work to do, it
will set:

sq_ring->flags |= IORING_SQ_NEED_WAKEUP.

The application will have to call io_uring_enter() to start things back
up again. If IO is kept busy, that will never be needed. Basically an
application that has this feature enabled will guard it's
io_uring_enter(2) call with:

read_barrier();
if (*sq_ring->flags & IORING_SQ_NEED_WAKEUP)
	io_uring_enter(fd, 0, 0, IORING_ENTER_SQ_WAKEUP);

instead of calling it unconditionally.

It's mandatory to use fixed files with this feature. Failure to do so
will result in the application getting an -EBADF CQ entry when
submitting IO.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We normally have to fget/fput for each IO we do on a file. Even with
the batching we do, the cost of the atomic inc/dec of the file usage
count adds up.

This adds IORING_REGISTER_FILES, and IORING_UNREGISTER_FILES opcodes
for the io_uring_register(2) system call. The arguments passed in must
be an array of __s32 holding file descriptors, and nr_args should hold
the number of file descriptors the application wishes to pin for the
duration of the io_uring instance (or until IORING_UNREGISTER_FILES is
called).

When used, the application must set IOSQE_FIXED_FILE in the sqe->flags
member. Then, instead of setting sqe->fd to the real fd, it sets sqe->fd
to the index in the array passed in to IORING_REGISTER_FILES.

Files are automatically unregistered when the io_uring instance is torn
down. An application need only unregister if it wishes to register a new
set of fds.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If we have fixed user buffers, we can map them into the kernel when we
setup the io_uring. That avoids the need to do get_user_pages() for
each and every IO.

To utilize this feature, the application must call io_uring_register()
after having setup an io_uring instance, passing in
IORING_REGISTER_BUFFERS as the opcode. The argument must be a pointer to
an iovec array, and the nr_args should contain how many iovecs the
application wishes to map.

If successful, these buffers are now mapped into the kernel, eligible
for IO. To use these fixed buffers, the application must use the
IORING_OP_READ_FIXED and IORING_OP_WRITE_FIXED opcodes, and then
set sqe->index to the desired buffer index. sqe->addr..sqe->addr+seq->len
must point to somewhere inside the indexed buffer.

The application may register buffers throughout the lifetime of the
io_uring instance. It can call io_uring_register() with
IORING_UNREGISTER_BUFFERS as the opcode to unregister the current set of
buffers, and then register a new set. The application need not
unregister buffers explicitly before shutting down the io_uring
instance.

It's perfectly valid to setup a larger buffer, and then sometimes only
use parts of it for an IO. As long as the range is within the originally
mapped region, it will work just fine.

For now, buffers must not be file backed. If file backed buffers are
passed in, the registration will fail with -1/EOPNOTSUPP. This
restriction may be relaxed in the future.

RLIMIT_MEMLOCK is used to check how much memory we can pin. A somewhat
arbitrary 1G per buffer size is also imposed.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add support for a polled io_uring instance. When a read or write is
submitted to a polled io_uring, the application must poll for
completions on the CQ ring through io_uring_enter(2). Polled IO may not
generate IRQ completions, hence they need to be actively found by the
application itself.

To use polling, io_uring_setup() must be used with the
IORING_SETUP_IOPOLL flag being set. It is illegal to mix and match
polled and non-polled IO on an io_uring.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add a new fsync opcode, which either syncs a range if one is passed,
or the whole file if the offset and length fields are both cleared
to zero.  A flag is provided to use fdatasync semantics, that is only
force out metadata which is required to retrieve the file data, but
not others like metadata.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The submission queue (SQ) and completion queue (CQ) rings are shared
between the application and the kernel. This eliminates the need to
copy data back and forth to submit and complete IO.

IO submissions use the io_uring_sqe data structure, and completions
are generated in the form of io_uring_cqe data structures. The SQ
ring is an index into the io_uring_sqe array, which makes it possible
to submit a batch of IOs without them being contiguous in the ring.
The CQ ring is always contiguous, as completion events are inherently
unordered, and hence any io_uring_cqe entry can point back to an
arbitrary submission.

Two new system calls are added for this:

io_uring_setup(entries, params)
	Sets up an io_uring instance for doing async IO. On success,
	returns a file descriptor that the application can mmap to
	gain access to the SQ ring, CQ ring, and io_uring_sqes.

io_uring_enter(fd, to_submit, min_complete, flags, sigset, sigsetsize)
	Initiates IO against the rings mapped to this fd, or waits for
	them to complete, or both. The behavior is controlled by the
	parameters passed in. If 'to_submit' is non-zero, then we'll
	try and submit new IO. If IORING_ENTER_GETEVENTS is set, the
	kernel will wait for 'min_complete' events, if they aren't
	already available. It's valid to set IORING_ENTER_GETEVENTS
	and 'min_complete' == 0 at the same time, this allows the
	kernel to return already completed events without waiting
	for them. This is useful only for polling, as for IRQ
	driven IO, the application can just check the CQ ring
	without entering the kernel.

With this setup, it's possible to do async IO with a single system
call. Future developments will enable polled IO with this interface,
and polled submission as well. The latter will enable an application
to do IO without doing ANY system calls at all.

For IRQ driven IO, an application only needs to enter the kernel for
completions if it wants to wait for them to occur.

Each io_uring is backed by a workqueue, to support buffered async IO
as well. We will only punt to an async context if the command would
need to wait for IO on the device side. Any data that can be accessed
directly in the page cache is done inline. This avoids the slowness
issue of usual threadpools, since cached data is accessed as quickly
as a sync interface.

Sample application: http://git.kernel.dk/cgit/fio/plain/t/io_uring.cReviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Return bpf program run_time_ns and run_cnt via bpf_prog_info
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Return the Page Aligned Request bit in the ATS Capability Register.

As per PCIe spec r4.0, sec 10.5.1.2, if the Page Aligned Request bit is
set, it indicates the Untranslated Addresses generated by the device are
always aligned to a 4096 byte boundary.

An IOMMU that can only translate page-aligned addresses can only be used
with devices that always produce aligned Untranslated Addresses. This
interface will be used by drivers for such IOMMUs to determine whether
devices can use the ATS service.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Suggested-by: NAshok Raj <ashok.raj@intel.com>
Signed-off-by: NKuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Return the PRG Response PASID Required bit in the Page Request
Status Register.

As per PCIe spec r4.0, sec 10.5.2.3, if this bit is Set, the device
expects a PASID TLP Prefix on PRG Response Messages when the
corresponding Page Requests had a PASID TLP Prefix. If Clear, the device
does not expect PASID TLP Prefixes on any PRG Response Message, and the
device behavior is undefined if the device receives a PRG Response Message
with a PASID TLP Prefix. Also the device behavior is undefined if this
bit is Set and the device receives a PRG Response Message with no PASID TLP
Prefix when the corresponding Page Requests had a PASID TLP Prefix.

This function will be used by drivers like IOMMU, if it is required to
check the status of the PRG Response PASID Required bit before enabling
the PASID support of the device.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Suggested-by: NAshok Raj <ashok.raj@intel.com>
Signed-off-by: NKuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The current implementation scales the local alpha and beta
variables in the calculate_probability function by the same
amount for all values of drop probability below 1%.

RFC 8033 suggests using additional cases for auto-tuning
alpha and beta when the drop probability is less than 1%.

In order to add more auto-tuning cases, MAX_PROB must be
scaled by u64 instead of u32 to prevent underflow when
scaling the local alpha and beta variables in the
calculate_probability function.
Signed-off-by: NMohit P. Tahiliani <tahiliani@nitk.edu.in>
Signed-off-by: NDhaval Khandla <dhavaljkhandla26@gmail.com>
Signed-off-by: NHrishikesh Hiraskar <hrishihiraskar@gmail.com>
Signed-off-by: NManish Kumar B <bmanish15597@gmail.com>
Signed-off-by: NSachin D. Patil <sdp.sachin@gmail.com>
Signed-off-by: NLeslie Monis <lesliemonis@gmail.com>
Acked-by: NDave Taht <dave.taht@gmail.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Support for a new command that can be used eg. as a command

  $ btrfs device scan --forget [dev]'
(the final name may change though)

to undo the effects of 'btrfs device scan [dev]'. For this purpose
this patch proposes to use ioctl #5 as it was empty and is next to the
SCAN ioctl.

The new ioctl BTRFS_IOC_FORGET_DEV works only on the control device
(/dev/btrfs-control) to unregister one or all devices, devices that are
not mounted.

The argument is struct btrfs_ioctl_vol_args, ::name specifies the device
path. To unregister all device, the path is an empty string.

Again, the devices are removed only if they aren't part of a mounte
filesystem.

This new ioctl provides:

- release of unwanted btrfs_fs_devices and btrfs_devices structures
  from memory if the device is not going to be mounted

- ability to mount filesystem in degraded mode, when one devices is
  corrupted like in split brain raid1

- running test cases which would require reloading the kernel module
  but this is not possible eg. due to mounted filesystem or built-in
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: NDavid Sterba <dsterba@suse.com>

The way to define __ETHTOOL_LINK_MODE_MASK_NBITS seems to be overly
complicated, go with a standard approach instead.
Whilst we're at it, move the comment to the right place.

v2:
- rebased
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the only way to clear the forwarding cache was to delete the
entries one by one using the MRT_DEL_MFC socket option or to destroy and
recreate the socket.

Create a new socket option which with the use of optional flags can
clear any combination of multicast entries (static or not static) and
multicast vifs (static or not static).

Calling the new socket option MRT_FLUSH with the flags MRT_FLUSH_MFC and
MRT_FLUSH_VIFS will clear all entries and vifs on the socket except for
static entries.
Signed-off-by: NCallum Sinclair <callum.sinclair@alliedtelesis.co.nz>
Signed-off-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename devlink health attributes for better reflect the attributes use.
Add COUNT prefix on error counter attribute and recovery counter
attribute.

Fixes: 7afe335a ("devlink: Add health get command")
Signed-off-by: NAya Levin <ayal@mellanox.com>
Signed-off-by: NEran Ben Elisha <eranbe@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no need to have DM core split discards on behalf of a DM target
now that blk_queue_split() handles splitting discards based on the
queue_limits.  A DM target just needs to set max_discard_sectors,
discard_granularity, etc, in queue_limits.
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

We already have a ЅPDX header, so no need to duplicate the information.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>

Added support for 50Gbps per lane link modes. Define various 50G, 100G
and 200G link modes using it.
Signed-off-by: NAya Levin <ayal@mellanox.com>
Reviewed-by: NEran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

media: add support for RCMM infrared remote controls.
Signed-off-by: NPatrick Lerda <patrick9876@free.fr>
Signed-off-by: NSean Young <sean@mess.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>

The formats added in this patch include:
 V4L2_PIX_FMT_AYUV32
 V4L2_PIX_FMT_XYUV32
 V4L2_PIX_FMT_VUYA32
 V4L2_PIX_FMT_VUYX32

These formats enable the trasmission of alpha channel data to other
drivers and userspace applications in addition to YUV data. For
example, buffers generated by drivers in one of these formats
can be used by the Weston compositor to display as a texture or
flipped directly onto the overlay planes with the help of a DRM
driver.
Signed-off-by: NVivek Kasireddy <vivek.kasireddy@intel.com>
Signed-off-by: NHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>

Now that we have 3 mmap flags shared by all architectures,
let's move them into the common header.

This will help discourage future architectures from duplicating code.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

Add devlink flash update command. Advanced NICs have firmware
stored in flash and often cryptographically secured. Updating
that flash is handled by management firmware. Ethtool has a
flash update command which served us well, however, it has two
shortcomings:
 - it takes rtnl_lock unnecessarily - really flash update has
   nothing to do with networking, so using a networking device
   as a handle is suboptimal, which leads us to the second one:
 - it requires a functioning netdev - in case device enters an
   error state and can't spawn a netdev (e.g. communication
   with the device fails) there is no netdev to use as a handle
   for flashing.

Devlink already has the ability to report the firmware versions,
now with the ability to update the firmware/flash we will be
able to recover devices in bad state.

To enable updates of sub-components of the FW allow passing
component name.  This name should correspond to one of the
versions reported in devlink info.

v1: - replace target id with component name (Jiri).
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we have a separate header for struct __kernel_timespec,
include it directly without relying on userspace to do it.
Reported-by: NRan Rozenstein <ranro@mellanox.com>
Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sys/time.h is the mandated include for many time related
defines. However, linux/time.h overlaps sys/time.h
significantly and this makes including both from userspace
or one from the other impossible.

This also means that userspace can get away with including
sys/time.h whenever it needs linux/time.h and this is what's
been happening in the user world usually.

But, we have new data types that we plan to use in the uapi time
interfaces also defined in the linux/time.h. But, we are unable
to use these types when sys/time.h is included.

Hence, move the new types to a new header, time_types.h.
We intend to eventually have all the uapi defines that the kernel
uses defined in this header.
Note that the plan is to replace uapi interfaces with timeval to
use __kernel_old_timeval, timespec to use __kernel_old_timespec etc.
Reported-by: NRan Rozenstein <ranro@mellanox.com>
Fixes: 9718475e ("socket: Add SO_TIMESTAMPING_NEW")
Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds all needed plumbing in preparation to allowing
bpf programs to do IP encapping via bpf_lwt_push_encap. Actual
implementation is added in the next patch in the patchset.

Of note:
- bpf_lwt_push_encap can now be called from BPF_PROG_TYPE_LWT_XMIT
  prog types in addition to BPF_PROG_TYPE_LWT_IN;
- if the skb being encapped has GSO set, encapsulation is limited
  to IPIP/IP+GRE/IP+GUE (both IPv4 and IPv6);
- as route lookups are different for ingress vs egress, the single
  external bpf_lwt_push_encap BPF helper is routed internally to
  either bpf_lwt_in_push_encap or bpf_lwt_xmit_push_encap BPF_CALLs,
  depending on prog type.

v8 changes: fixed a typo.
Signed-off-by: NPeter Oskolkov <posk@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

The 802.3bz specification, based on previous by the NBASET alliance,
defines the 2.5GBaseT and 5GBaseT link modes for ethernet traffic on
cat5e, cat6 and cat7 cables.

These mode integrate with the already defined C45 MDIO PMA/PMD registers
set that added 10G support, by defining some previously reserved bits,
and adding a new register (2.5G/5G Extended abilities).

This commit adds the required definitions in include/uapi/linux/mdio.h
to support these modes, and detect when a link-partner advertises them.

It also adds support for these mode in the generic C45 PHY
infrastructure.
Signed-off-by: NMaxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: NHeiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow filesystems to return ENOSYS from opendir, preventing the kernel from
sending opendir and releasedir messages in the future. This avoids
userspace transitions when filesystems don't need to keep track of state
per directory handle.

A new capability flag, FUSE_NO_OPENDIR_SUPPORT, parallels
FUSE_NO_OPEN_SUPPORT, indicating the new semantics for returning ENOSYS
from opendir.
Signed-off-by: NChad Austin <chadaustin@fb.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>

Field idiag_ext in struct inet_diag_req_v2 used as bitmap of requested
extensions has only 8 bits. Thus extensions starting from DCTCPINFO
cannot be requested directly. Some of them included into response
unconditionally or hook into some of lower 8 bits.

Extension INET_DIAG_CLASS_ID has not way to request from the beginning.

This patch bundle it with INET_DIAG_TCLASS (ipv6 tos), fixes space
reservation, and documents behavior for other extensions.

Also this patch adds fallback to reporting socket priority. This filed
is more widely used for traffic classification because ipv4 sockets
automatically maps TOS to priority and default qdisc pfifo_fast knows
about that. But priority could be changed via setsockopt SO_PRIORITY so
INET_DIAG_TOS isn't enough for predicting class.

Also cgroup2 obsoletes net_cls classid (it always zero), but we cannot
reuse this field for reporting cgroup2 id because it is 64-bit (ino+gen).

So, after this patch INET_DIAG_CLASS_ID will report socket priority
for most common setup when net_cls isn't set and/or cgroup2 in use.

Fixes: 0888e372 ("net: inet: diag: expose sockets cgroup classid")
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a helper function BPF_FUNC_tcp_sock and it
is currently available for cg_skb and sched_(cls|act):

struct bpf_tcp_sock *bpf_tcp_sock(struct bpf_sock *sk);

int cg_skb_foo(struct __sk_buff *skb) {
	struct bpf_tcp_sock *tp;
	struct bpf_sock *sk;
	__u32 snd_cwnd;

	sk = skb->sk;
	if (!sk)
		return 1;

	tp = bpf_tcp_sock(sk);
	if (!tp)
		return 1;

	snd_cwnd = tp->snd_cwnd;
	/* ... */

	return 1;
}

A 'struct bpf_tcp_sock' is also added to the uapi bpf.h to provide
read-only access.  bpf_tcp_sock has all the existing tcp_sock's fields
that has already been exposed by the bpf_sock_ops.
i.e. no new tcp_sock's fields are exposed in bpf.h.

This helper returns a pointer to the tcp_sock.  If it is not a tcp_sock
or it cannot be traced back to a tcp_sock by sk_to_full_sk(), it
returns NULL.  Hence, the caller needs to check for NULL before
accessing it.

The current use case is to expose members from tcp_sock
to allow a cg_skb_bpf_prog to provide per cgroup traffic
policing/shaping.
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>