xref: /illumos-gate/usr/src/man/man9e/mi_enable.9e (revision 0250c53ad267726f2438e3c6556199a0bbf588a2)
1.\"
2.\" This file and its contents are supplied under the terms of the
3.\" Common Development and Distribution License ("CDDL"), version 1.0.
4.\" You may only use this file in accordance with the terms of version
5.\" 1.0 of the CDDL.
6.\"
7.\" A full copy of the text of the CDDL should have accompanied this
8.\" source.  A copy of the CDDL is also available via the Internet at
9.\" http://www.illumos.org/license/CDDL.
10.\"
11.\"
12.\" Copyright (c) 2017, Joyent, Inc.
13.\" Copyright 2022 Oxide Computer Company
14.\"
15.Dd July 2, 2022
16.Dt MI_ENABLE 9E
17.Os
18.Sh NAME
19.Nm mi_enable ,
20.Nm mi_disable
21.Nd MAC interrupt enable and disable entry points
22.Sh SYNOPSIS
23.In sys/mac_provider.h
24.Ft int
25.Fo prefix_intr_enable
26.Fa "mac_intr_handle_t driver"
27.Fc
28.Ft int
29.Fo prefix_intr_disable
30.Fa "mac_intr_handle_t driver"
31.Fc
32.Sh INTERFACE LEVEL
33.Sy Uncommitted -
34This interface is still evolving.
35API and ABI stability is not guaranteed.
36.Sh PARAMETERS
37.Bl -tag -width Fa
38.It Fa driver
39A pointer to the mac interrupt's private data that was passed in via the
40.Vt mi_handle
41member of the
42.Xr mac_intr 9S
43structure.
44.El
45.Sh DESCRIPTION
46The
47.Fn mi_enable
48and
49.Fn mi_disable
50entry points are used by the MAC framework when it wishes to disable the
51generation of interrupts for the ring and poll on the it through the
52.Xr mri_poll 9E
53entry point.
54.Pp
55These entry points should enable and disable the generation of the
56interrupt for the ring that is represented by
57.Fa driver .
58The
59.Fa driver
60argument corresponds to what the driver set in the
61.Fa mri_intr
62member while filling out the
63.Xr mac_ring_info 9S
64structure and generally is used to point to a specific ring.
65.Pp
66Importantly, this entry point is not asking to enable and disable the
67underlying device-level interrupt such as a PCIe MSI or MSI-X, which may
68be being used by multiple rings.
69Drivers must not implement this in terms of the DDI interrupt functions
70such as
71.Xr ddi_intr_enable 9F
72and
73.Xr ddi_intr_disable 9F .
74.Pp
75Instead this should be implemented through device specific means such as
76writing to registers or sending control messages to enable or disable
77the generation of interrupts for the specified ring.
78.Pp
79When manipulating the device's control of interrupts, the driver should
80be careful to serialize these changes with the ongoing processing of
81interrupts through the interrupt handler and the
82.Xr mri_poll 9E
83entry point.
84These should all be protected by the same mutex which is scoped to the
85ring itself when the ability to turn on and off interrupt generation may
86be manipulated on a per-ring basis.
87Failure to properly synchronize this may lead to the driver mistakenly
88delivering the same packet twice through both its interrupt handler and
89its
90.Xr mri_poll 9E
91entry point.
92.Sh RETURN VALUES
93Upon successful completion, the
94.Fn mi_enable
95and
96.Fn mi_disable
97entry points should return
98.Sy 0 .
99Otherwise the appropriate error number should be returned.
100.Sh SEE ALSO
101.Xr mac 9E ,
102.Xr mac_capab_rings 9E ,
103.Xr mri_poll 9E ,
104.Xr ddi_intr_disable 9F ,
105.Xr ddi_intr_enable 9F ,
106.Xr mac_intr 9S ,
107.Xr mac_ring_info 9S
108