xref: /openbsd-src/share/man/man9/ifiq_input.9 (revision 41ce3b17e73f6b7d2d9e1a3d961e4bab2d895cb5)
1*41ce3b17Snaddy.\" $OpenBSD: ifiq_input.9,v 1.4 2022/03/31 17:27:23 naddy Exp $
26cb86191Sdlg.\"
36cb86191Sdlg.\" Copyright (c) 2020 David Gwynne <dlg@openbsd.org>
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17*41ce3b17Snaddy.Dd $Mdocdate: March 31 2022 $
186cb86191Sdlg.Dt IFIQ_INPUT 9
196cb86191Sdlg.Os
206cb86191Sdlg.Sh NAME
216cb86191Sdlg.Nm ifiq_input ,
226cb86191Sdlg.Nm ifiq_enqueue
236cb86191Sdlg.Nd network interface input queue (ifiqueue) API
246cb86191Sdlg.Sh SYNOPSIS
256cb86191Sdlg.In net/if_var.h
266cb86191Sdlg.Ft int
276cb86191Sdlg.Fn ifiq_input "struct ifiqueue *ifiq" "struct mbuf_list *ml"
286cb86191Sdlg.Ft void
296cb86191Sdlg.Fn ifiq_enqueue "struct ifiqueue *ifiq" "struct mbuf *m"
306cb86191Sdlg.Sh DESCRIPTION
316cb86191SdlgThe network interface input queue (ifiqueue) API provides functions
326cb86191Sdlgfor network drivers to queue received packets for processing by the
336cb86191Sdlgnetwork stack.
346cb86191Sdlg.Bl -tag -width Ds
356cb86191Sdlg.It Fn ifiq_input "struct ifiqueue *ifq" "struct mbuf_list *ml"
366cb86191SdlgEnqueue the list of mbufs in
376cb86191Sdlg.Fa ml
386cb86191Sdlgon the
396cb86191Sdlg.Fa ifiq
406cb86191Sdlginterface input queue and notify the network stack to process them.
41*41ce3b17SnaddyIf the queue rejects the packets, they will be freed
42a672f2afSjmcand counted as drops.
436cb86191Sdlg.It Fn ifiq_enqueue "struct ifiqueue *ifq" "struct mbuf *m"
446cb86191SdlgEnqueue the mbuf
456cb86191Sdlg.Fa m
466cb86191Sdlgon the
476cb86191Sdlg.Fa ifiq
486cb86191Sdlginterface input queue and notify the network stack to process it.
496cb86191Sdlg.El
506cb86191Sdlg.Sh CONTEXT
51a672f2afSjmc.Fn ifiq_input
526cb86191Sdlgand
536cb86191Sdlg.Fn ifiq_enqueue
546cb86191Sdlgcan be called during autoconf, from process context, or from interrupt context.
556cb86191Sdlg.Sh RETURN VALUES
566cb86191Sdlg.Fn ifiq_input
576cb86191Sdlgreturns a non-zero value if mbufs are queued too rapidly for the
586cb86191Sdlgstack to process.
596cb86191SdlgIf possible, the caller should attempt to reduce the number of mbufs
60a672f2afSjmcbeing generated in the future.
61a672f2afSjmcFor example, if mbufs are being received from
626cb86191Sdlghardware managed with the interface RX ring API,
635c51f77dSdlg.Xr if_rxr_livelocked 9
646cb86191Sdlgcan be called to indicate to the hardware that backpressure is required.
656cb86191Sdlg.Sh SEE ALSO
665c51f77dSdlg.Xr if_rxr_livelocked 9
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