xref: /illumos-gate/usr/src/man/man9f/mac_rx.9f (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
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12.\" Copyright (c) 2017, Joyent, Inc.
13.\" Copyright 2022 Oxide Compuer Company
14.\"
15.Dd July 2, 2022
16.Dt MAC_RX 9F
17.Os
18.Sh NAME
19.Nm mac_rx ,
20.Nm mac_ring_rx
21.Nd deliver frames from a driver to the system
22.Sh SYNOPSIS
23.In sys/mac_provider.h
24.Ft void
25.Fo mac_rx
26.Fa "mac_handle_t mh"
27.Fa "mac_resource_handle_t mrh"
28.Fa "mblk_t *mp_chain"
29.Fc
30.Ft void
31.Fo mac_rx_ring
32.Fa "mac_handle_t mh"
33.Fa "mac_ring_handle_t mring"
34.Fa "mblk_t *mp_chain"
35.Fa "uint64_t mr_gen"
36.Fc
37.Sh INTERFACE LEVEL
38illumos DDI specific
39.Pp
40The
41.Fn mac_rx_ring
42function point is
43.Sy Uncommitted -
44API and ABI stability is not guaranteed.
45.Sh PARAMETERS
46.Bl -tag -width Fa
47.It Fa mh
48The MAC handle obtained from a call to
49.Xr mac_register 9F .
50.It Fa mrh
51A reserved parameter that should be passed as
52.Dv NULL .
53.It Fa mring
54A pointer to the ring handle that was passed to the driver in the
55.Xr mr_rget 9E
56entry point.
57.It Fa mp_chain
58A series of one or more
59.Xr mblk 9S
60structures chained together by their
61.Sy b_next
62member.
63.It Fa mr_gen
64The generation number for the current ring.
65The generation comes from the
66.Xr mri_start 9E
67entry point.
68.El
69.Sh DESCRIPTION
70The
71.Fn mac_rx
72function is used by device drivers to deliver frames that a device
73driver has received to the rest of the operating system.
74This will generally be called at the end of a device driver's interrupt handler
75after it is has converted all of the incoming data into a chain of
76.Xr mblk 9S
77structures.
78For a full description of the process that the device driver should take as part
79of receiving data, see the
80.Sx Receiving Data
81section of
82.Xr mac 9E .
83.Pp
84Device drivers should ensure that they are not holding any of their own
85locks when they call the
86.Fn mac_rx
87function.
88.Pp
89Device drivers should not call the
90.Fn mac_rx
91function after each individual mblk_t is assembled.
92Rather, the device driver should batch up as many frames as it is willing to
93process in a given interrupt or are available.
94.Pp
95The
96.Fn mac_rx_ring
97function is similar to the
98.Fa mac_rx
99function; however, it should be called by device drivers that have
100negotiated the
101.Dv MAC_CAPAB_RINGS
102capability and indicated that it supports receive groups.
103Device drivers that have negotiated this capability must not call the
104.Fn mac_rx
105function, but use the
106.Fn mac_rx_ring
107function instead.
108The driver should pass the ring handle in
109.Fa mring
110for the ring in question that it processed.
111If more than one ring was processed during an interrupt, then the driver
112must call
113.Fn mac_ring_rx
114once for each ring and ensure that the
115.Fa mr_gen
116argument matches what was passed to the driver during the
117.Xr mri_start 9E
118entry point for each ring.
119If the value of
120.Fa mr_gen
121does not match what the operating system expects, all of the packets
122will be dropped.
123This is used to make sure that the system is receiving what it considers
124valid data from the device driver.
125.Pp
126When a driver supporting the
127.Dv MAC_CAPAB_RINGS
128capability is asked to poll via their
129.Xr mri_poll 9E
130entry point, then the driver should not call the
131.Fn mac_ring_rx
132function to deliver packets and instead returns them during the
133.Xr mri_poll 9E
134call.
135.Sh CONTEXT
136The
137.Fn mac_rx
138function can be called from
139.Sy user ,
140.Sy kernel ,
141or
142.Sy interrupt
143context.
144.Sh SEE ALSO
145.Xr mac 9E ,
146.Xr mac_capab_rings 9E ,
147.Xr mr_rget 9E ,
148.Xr mri_poll 9E ,
149.Xr mri_start 9E ,
150.Xr mac_register 9F ,
151.Xr mblk 9S
152