xref: /illumos-gate/usr/src/man/man9f/mac_rx.9f (revision d5b563f27eb78296f57dddced6755afe7445c4b9)
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12.\" Copyright (c) 2017, Joyent, Inc.
13.\" Copyright 2022 Oxide Compuer Company
14.\" Copyright 2023 Peter Tribble
15.\"
16.Dd July 17, 2023
17.Dt MAC_RX 9F
18.Os
19.Sh NAME
20.Nm mac_rx ,
21.Nm mac_rx_ring
22.Nd deliver frames from a driver to the system
23.Sh SYNOPSIS
24.In sys/mac_provider.h
25.Ft void
26.Fo mac_rx
27.Fa "mac_handle_t mh"
28.Fa "mac_resource_handle_t mrh"
29.Fa "mblk_t *mp_chain"
30.Fc
31.Ft void
32.Fo mac_rx_ring
33.Fa "mac_handle_t mh"
34.Fa "mac_ring_handle_t mring"
35.Fa "mblk_t *mp_chain"
36.Fa "uint64_t mr_gen"
37.Fc
38.Sh INTERFACE LEVEL
39illumos DDI specific
40.Pp
41The
42.Fn mac_rx_ring
43function point is
44.Sy Uncommitted -
45API and ABI stability is not guaranteed.
46.Sh PARAMETERS
47.Bl -tag -width Fa
48.It Fa mh
49The MAC handle obtained from a call to
50.Xr mac_register 9F .
51.It Fa mrh
52A reserved parameter that should be passed as
53.Dv NULL .
54.It Fa mring
55A pointer to the ring handle that was passed to the driver in the
56.Xr mr_rget 9E
57entry point.
58.It Fa mp_chain
59A series of one or more
60.Xr mblk 9S
61structures chained together by their
62.Sy b_next
63member.
64.It Fa mr_gen
65The generation number for the current ring.
66The generation comes from the
67.Xr mri_start 9E
68entry point.
69.El
70.Sh DESCRIPTION
71The
72.Fn mac_rx
73function is used by device drivers to deliver frames that a device
74driver has received to the rest of the operating system.
75This will generally be called at the end of a device driver's interrupt handler
76after it is has converted all of the incoming data into a chain of
77.Xr mblk 9S
78structures.
79For a full description of the process that the device driver should take as part
80of receiving data, see the
81.Sx Receiving Data
82section of
83.Xr mac 9E .
84.Pp
85Device drivers should ensure that they are not holding any of their own
86locks when they call the
87.Fn mac_rx
88function.
89.Pp
90Device drivers should not call the
91.Fn mac_rx
92function after each individual mblk_t is assembled.
93Rather, the device driver should batch up as many frames as it is willing to
94process in a given interrupt or are available.
95.Pp
96The
97.Fn mac_rx_ring
98function is similar to the
99.Fa mac_rx
100function; however, it should be called by device drivers that have
101negotiated the
102.Dv MAC_CAPAB_RINGS
103capability and indicated that it supports receive groups.
104Device drivers that have negotiated this capability must not call the
105.Fn mac_rx
106function, but use the
107.Fn mac_rx_ring
108function instead.
109The driver should pass the ring handle in
110.Fa mring
111for the ring in question that it processed.
112If more than one ring was processed during an interrupt, then the driver
113must call
114.Fn mac_rx_ring
115once for each ring and ensure that the
116.Fa mr_gen
117argument matches what was passed to the driver during the
118.Xr mri_start 9E
119entry point for each ring.
120If the value of
121.Fa mr_gen
122does not match what the operating system expects, all of the packets
123will be dropped.
124This is used to make sure that the system is receiving what it considers
125valid data from the device driver.
126.Pp
127When a driver supporting the
128.Dv MAC_CAPAB_RINGS
129capability is asked to poll via their
130.Xr mri_poll 9E
131entry point, then the driver should not call the
132.Fn mac_rx_ring
133function to deliver packets and instead returns them during the
134.Xr mri_poll 9E
135call.
136.Sh CONTEXT
137The
138.Fn mac_rx
139function can be called from
140.Sy user ,
141.Sy kernel ,
142or
143.Sy interrupt
144context.
145.Sh SEE ALSO
146.Xr mac 9E ,
147.Xr mac_capab_rings 9E ,
148.Xr mr_rget 9E ,
149.Xr mri_poll 9E ,
150.Xr mri_start 9E ,
151.Xr mac_register 9F ,
152.Xr mblk 9S
153