netmap: disable passthrough with no hypervisor support

The netmap passthrough subsystem requires proper support in the
hypervisor. In particular, two PCI device ids (from the Red Hat
PCI vendor id 0

netmap: disable passthrough with no hypervisor support

The netmap passthrough subsystem requires proper support in the
hypervisor. In particular, two PCI device ids (from the Red Hat
PCI vendor id 0x1b36) need to be assigned to the two netmap
virtual devices. We then disable these devices until the ids have
not been assigned, in order to avoid conflicts with other
virtual devices emulated by upstream QEMU.

PR: 241774
MFC after: 3 days

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Merge ^/head r351317 through r351731.

netmap: import changes from upstream (SHA 137f537eae513)

- Rework option processing.
- Use larger integers for memory size values in the
memory management code.

MFC after: 2 weeks

Merge ^/head r344178 through r344512.

MFhead@r344270

netmap: don't schedule kqueue notify task when kqueue is not used

This change adds a counter (kqueue_users) to keep track of how many
kqueue users are referencing a given struct nm_selinfo.
In this

netmap: don't schedule kqueue notify task when kqueue is not used

This change adds a counter (kqueue_users) to keep track of how many
kqueue users are referencing a given struct nm_selinfo.
In this way, nm_os_selwakeup() can schedule the kevent notification
task only when kqueue is actually being used.
This is important to avoid wasting CPU in the common case where
kqueue is not used.

Reviewed by: Aleksandr Fedorov <aleksandr.fedorov@itglobal.com>
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D19177

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Merge ^/head r343712 through r343806.

netmap: refactor logging macros and pipes

Changelist:
- Replace ND, D and RD macros with nm_prdis, nm_prinf, nm_prerr
and nm_prlim, to avoid possible naming conflicts.
- Add netmap_kri

netmap: refactor logging macros and pipes

Changelist:
- Replace ND, D and RD macros with nm_prdis, nm_prinf, nm_prerr
and nm_prlim, to avoid possible naming conflicts.
- Add netmap_krings_mode_commit() helper function and use that
to reduce code duplication.
- Refactor pipes control code to export some functions that
can be reused by the veth driver (on Linux) and epair(4).
- Add check to reject API requests with version less than 11.
- Small code refactoring for the null adapter.

MFC after: 1 week

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Merge ^/head r343571 through r343711.

netmap: upgrade sync-kloop support

Add SYNC_KLOOP_MODE option, and add support for direct mode, where application
executes the TXSYNC and RXSYNC in the context of the ioeventfd wake up callback.

MF

netmap: upgrade sync-kloop support

Add SYNC_KLOOP_MODE option, and add support for direct mode, where application
executes the TXSYNC and RXSYNC in the context of the ioeventfd wake up callback.

MFC after: 5 days

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netmap: fix lock order reversal related to kqueue usage

When using poll(), select() or kevent() on netmap file descriptors,
netmap executes the equivalent of NIOCTXSYNC and NIOCRXSYNC commands,
befo

netmap: fix lock order reversal related to kqueue usage

When using poll(), select() or kevent() on netmap file descriptors,
netmap executes the equivalent of NIOCTXSYNC and NIOCRXSYNC commands,
before collecting the events that are ready. In other words, the
poll/kevent callback has side effects. This is done to avoid the
overhead of two system call per iteration (e.g., poll() + ioctl(NIOC*XSYNC)).

When the kqueue subsystem invokes the kqueue(9) f_event callback
(netmap_knrw), it holds the lock of the struct knlist object associated
to the netmap port (the lock is provided at initialization, by calling
knlist_init_mtx).
However, netmap_knrw() may need to wake up another netmap port (or even
the same one), which means that it may need to call knote().
Since knote() needs the lock of the struct knlist object associated to
the to-be-wake-up netmap port, it is possible to have a lock order reversal
problem (AB/BA deadlock).

This change prevents the deadlock by executing the knote() call in a
per-selinfo taskqueue, where it is possible to hold a mutex.

Reviewed by: aleksandr.fedorov_itglobal.com
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D18956

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Merge ^/head r343320 through r343570.

netmap: improvements to the netmap kloop (CSB mode)

Changelist:
- Add the proper memory barriers in the kloop ring processing
functions.
- Fix memory barriers usage in the user helpers

netmap: improvements to the netmap kloop (CSB mode)

Changelist:
- Add the proper memory barriers in the kloop ring processing
functions.
- Fix memory barriers usage in the user helpers (nm_sync_kloop_appl_write,
nm_sync_kloop_appl_read).
- Fix nm_kr_txempty() helper to look at rhead rather than rcur. This
is important since the kloop can read a value of rcur which is ahead
of the value of rhead (see explanation in nm_sync_kloop_appl_write)
- Remove obsolete ptnetmap_guest_write_kring_csb() and
ptnet_guest_read_kring_csb(), and update if_ptnet(4) to use those.
- Prepare in advance the arguments for netmap_sync_kloop_[tr]x_ring(),
to make the kloop faster.
- Provide kernel and user implementation for nm_ldld_barrier() and
nm_ldst_barrier()

MFC after: 2 weeks

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netmap: fix knote() argument to match the mutex state

The nm_os_selwakeup function needs to call knote() to wake up kqueue(9)
users. However, this function can be called from different code paths,
w

netmap: fix knote() argument to match the mutex state

The nm_os_selwakeup function needs to call knote() to wake up kqueue(9)
users. However, this function can be called from different code paths,
with different lock requirements.
This patch fixes the knote() call argument to match the relavant lock state.
Also, comments have been updated to reflect current code.

PR: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=219846
Reported by: Aleksandr Fedorov <aleksandr.fedorov@itglobal.com>
Reviewed by: markj
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D18876

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netmap: move buf_size validation code to its own function

This code validates the netmap buf_size against the interface MTU
and maximum descriptor size, to make sure the values are consistent.
Movin

netmap: move buf_size validation code to its own function

This code validates the netmap buf_size against the interface MTU
and maximum descriptor size, to make sure the values are consistent.
Moving this functionality to its own function is needed because this
function is also called by Linux-specific code.

MFC after: 3 days

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Merge ^/head r340918 through r341763.

netmap: align codebase to the current upstream (760279cfb2730a585)

Changelist:
- Replace netmap passthrough host support with a more general
mechanism to call TXSYNC/RXSYNC from an in-kernel e

netmap: align codebase to the current upstream (760279cfb2730a585)

Changelist:
- Replace netmap passthrough host support with a more general
mechanism to call TXSYNC/RXSYNC from an in-kernel event-loop.
No kernel threads are used to use this feature: the application
is required to spawn a thread (or a process) and issue a
SYNC_KLOOP_START (NIOCCTRL) command in the thread body. The
kernel loop is executed by the ioctl implementation, which returns
to userspace only when a different thread calls SYNC_KLOOP_STOP
or the netmap file descriptor is closed.
- Update the if_ptnet driver to cope with the new data structures,
and prune all the obsolete ptnetmap code.
- Add support for "null" netmap ports, useful to allocate netmap_if,
netmap_ring and netmap buffers to be used by specialized applications
(e.g. hypervisors). TXSYNC/RXSYNC on these ports have no effect.
- Various fixes and code refactoring.

Sponsored by: Sunny Valley Networks
Differential Revision: https://reviews.freebsd.org/D18015

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Merge ^/head r339015 through r339669.

netmap: align codebase to the current upstream (sha 8374e1a7e6941)

Changelist:
- Move large parts of VALE code to a new file and header netmap_bdg.[ch].
This is useful to reuse the code wi

netmap: align codebase to the current upstream (sha 8374e1a7e6941)

Changelist:
- Move large parts of VALE code to a new file and header netmap_bdg.[ch].
This is useful to reuse the code within upcoming projects.
- Improvements and bug fixes to pipes and monitors.
- Introduce nm_os_onattach(), nm_os_onenter() and nm_os_onexit() to
handle differences between FreeBSD and Linux.
- Introduce some new helper functions to handle more host rings and fake
rings (netmap_all_rings(), netmap_real_rings(), ...)
- Added new sysctl to enable/disable hw checksum in emulated netmap mode.
- nm_inject: add support for NS_MOREFRAG

Approved by: gnn (mentor)
Differential Revision: https://reviews.freebsd.org/D17364

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netmap: Make memory pools NUMA-aware

Each netmap adapter associated with a physical adapter is attached to a
netmap memory pool. contigmalloc() is used to allocate physically
contiguous memory for

netmap: Make memory pools NUMA-aware

Each netmap adapter associated with a physical adapter is attached to a
netmap memory pool. contigmalloc() is used to allocate physically
contiguous memory for the pool, but ideally we would ensure that all
such memory is allocated from the NUMA domain local to the adapter.

Augment netmap's memory pools with a NUMA domain ID, similar to how
IOMMU groups are handled in the Linux port. That is, when attaching to
a physical adapter, ensure that the associated memory pools are local to
the adapter's associated memory domain, creating new pools as needed.

Some types of ifnets do not have any defined NUMA affinity; in this case
the domain ID in question is the sentinel value -1.

Add a sysctl, dev.netmap.port_numa_affinity, which can be used to enable
the new behaviour. Keep it disabled by now to avoid surprises in case
netmap applications are relying on zero-copy optimizations to forward
packets between ports belonging to different NUMA domains.

Reviewed by: vmaffione
MFC after: 2 weeks
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D46666

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netmap: Address errors on memory free in netmap_generic

netmap_generic keeps a pool of mbufs for handling transfers, these mbufs
have an external buffer attached to them.

If some cases other parts

netmap: Address errors on memory free in netmap_generic

netmap_generic keeps a pool of mbufs for handling transfers, these mbufs
have an external buffer attached to them.

If some cases other parts of the network stack can chain these mbufs,
when this happens the normal pool destructor function can end up
free'ing the pool mbufs twice:

- A first time if a pool mbuf has been chained with another mbuf when
its chain is freed
- A second time when its entry in the pool is freed

Additionally, if other parts of the stack demote a pool mbuf its
interface reference will be cleared. In this case we deference a NULL
pointer when trying to free the mbuf through the destructor. Store a
reference to the adapter in ext_arg1 with the destructor callback so we
can find the correct adapter when free'ing a pool mbuf.

This change enables using netmap with epair interfaces.

Reviewed By: vmaffione
MFC after: 1 week
Relnotes: yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D44371

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netmap: Ignore errors in CSB_WRITE()

The CSB_WRITE() and _READ() macros respectively write to and read from
userspace memory and so can in principle fault. However, we do not
check for errors and w

netmap: Ignore errors in CSB_WRITE()

The CSB_WRITE() and _READ() macros respectively write to and read from
userspace memory and so can in principle fault. However, we do not
check for errors and will proceed blindly if they fail. Add assertions
to verify that they do not.

This is in preparation for annotating copyin() and related functions
with __result_use_check.

Reviewed by: vmaffione
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D43200

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sys: Remove $FreeBSD$: one-line .h pattern

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

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netmap: Fix queue stalls with generic interfaces

In emulated mode, the FreeBSD netmap port attempts to perform zero-copy
transmission. This works as follows: the kernel ring is populated with
mbuf

netmap: Fix queue stalls with generic interfaces

In emulated mode, the FreeBSD netmap port attempts to perform zero-copy
transmission. This works as follows: the kernel ring is populated with
mbuf headers to which netmap buffers are attached. When transmitting,
the mbuf refcount is initialized to 2, and when the counter value has
been decremented to 1 netmap infers that the driver has freed the mbuf
and thus transmission is complete.

This scheme does not generalize to the situation where netmap is
attaching to a software interface which may transmit packets among
multiple "queues", as is the case with bridge or lagg interfaces. In
that case, we would be relying on backing hardware drivers to free
transmitted mbufs promptly, but this isn't guaranteed; a driver may
reasonably defer freeing a small number of transmitted buffers
indefinitely. If such a buffer ends up at the tail of a netmap transmit
ring, further transmits can end up blocked indefinitely.

Fix the problem by removing the zero-copy scheme (which is also not
implemented in the Linux port of netmap). Instead, the kernel ring is
populated with regular mbuf clusters into which netmap buffers are
copied by nm_os_generic_xmit_frame(). The refcounting scheme is
preserved, and this lets us avoid allocating a fresh cluster per
transmitted packet in the common case. If the transmit ring is full, a
callout is used to free the "stuck" mbuf, avoiding the queue deadlock
described above.

Furthermore, when recycling mbuf clusters, be sure to fully reinitialize
the mbuf header instead of simply re-setting M_PKTHDR. Some software
interfaces, like if_vlan, may set fields in the header which should be
reset before the mbuf is reused.

Reviewed by: vmaffione
MFC after: 1 month
Sponsored by: Zenarmor
Sponsored by: OPNsense
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D38065

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