xref: /illumos-gate/usr/src/man/man9s/cb_ops.9s (revision 66597161e2ba69a84fa138bce7ac02a1e6b9746c)
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17.Dd July 9, 2018
18.Dt CB_OPS 9S
19.Os
20.Sh NAME
21.Nm cb_ops
22.Nd character/block entry points structure
23.Sh SYNOPSIS
24.In sys/conf.h
25.In sys/ddi.h
26.In sys/sunddi.h
27.Sh INTERFACE LEVEL
28illumos DDI specific (illumos DDI)
29.Sh DESCRIPTION
30The
31.Nm
32structure contains all entry points for drivers that support
33both character and block entry points.
34All leaf device drivers that support
35direct user process access to a device should declare a
36.Nm
37structure.
38.Pp
39All drivers that safely allow multiple threads of execution in the driver at
40the same time must set the
41.Dv D_MP
42flag in the
43.Fa cb_flag
44field.
45See
46.Xr open 9E .
47.Pp
48If the driver properly handles 64-bit offsets, it should also set the
49.Dv D_64BIT
50flag in the
51.Fa cb_flag
52field.
53This specifies that the driver
54will use the
55.Fa uio_loffset
56field of the
57.Xr uio 9S
58structure.
59.Pp
60If the driver returns
61.Er EINTR
62from
63.Xr open 9E ,
64it should also set the
65.Dv D_OPEN_RETURNS_EINTR
66flag in the
67.Fa cb_flag
68field.
69This lets the
70framework know that it is safe for the driver to return
71.Er EINTR
72when waiting, to provide exclusion for a last-reference
73.Xr close 9E
74call to complete before calling
75.Xr open 9E .
76.Pp
77The
78.Xr mt-streams 9F
79function describes other flags that can be set in the
80.Fa cb_flag
81field.
82.Pp
83The
84.Fa cb_rev
85is the
86.Vt cb_ops
87structure revision number.
88This field must
89be set to
90.Dv CB_REV .
91.Pp
92.Pf Non- Ns Sy STREAMS
93drivers should set
94.Fa cb_str
95to
96.Sy NULL .
97.Pp
98The following
99.Sy DDI/DKI
100or
101.Sy DKI Ns -only
102or
103.Sy DDI Ns -only
104functions are provided in the character/block driver operations structure.
105.Bl -column "block/char" "Function" "Description"
106.It block/char	Function	Description
107.It b/c	XXopen	DDI/DKI
108.It b/c	XXclose	DDI/DKI
109.It b	XXstrategy	DDI/DKI
110.It b	XXprint	DDI/DKI
111.It b	XXdump	DDI(Sun)
112.It c	XXread	DDI/DKI
113.It c	XXwrite	DDI/DKI
114.It c	XXioctl	DDI/DKI
115.It c	XXdevmap	DDI(Sun)
116.It c	XXmmap	DKI
117.It c	XXsegmap	DKI
118.It c	XXchpoll	DDI/DKI
119.It c	XXprop_op	DDI(Sun)
120.It c	XXaread	DDI(Sun)
121.It c	XXawrite	DDI(Sun)
122.El
123.Sh STRUCTURE MEMBERS
124.Bd -literal -offset 2n
125int  (*cb_open)(dev_t *devp, int flag, int otyp, cred_t *credp);
126int  (*cb_close)(dev_t dev, int flag, int otyp, cred_t *credp);
127int  (*cb_strategy)(struct buf *bp);
128int  (*cb_print)(dev_t dev, char *str);
129int  (*cb_dump)(dev_t dev, caddr_t addr, daddr_t blkno, int nblk);
130int  (*cb_read)(dev_t dev, struct uio *uiop, cred_t *credp);
131int  (*cb_write)(dev_t dev, struct uio *uiop, cred_t *credp);
132int  (*cb_ioctl)(dev_t dev, int cmd, intptr_t arg, int mode,
133       cred_t *credp, int *rvalp);
134int  (*cb_devmap)(dev_t dev, devmap_cookie_t dhp, offset_t off,
135       size_t len, size_t *maplen, uint_t model);
136int  (*cb_mmap)(dev_t dev, off_t off, int prot);
137int  (*cb_segmap)(dev_t dev, off_t off, struct as *asp,
138       caddr_t *addrp, off_t len, unsigned int prot,
139       unsigned int maxprot, unsigned int flags, cred_t *credp);
140int  (*cb_chpoll)(dev_t dev, short events, int anyyet,
141       short *reventsp, struct pollhead **phpp);
142int  (*cb_prop_op)(dev_t dev, dev_info_t *dip,
143       ddi_prop_op_t prop_op, int mod_flags,
144       char *name, caddr_t valuep, int *length);
145struct streamtab *cb_str;   /* streams information */
146int  cb_flag;
147int  cb_rev;
148int  (*cb_aread)(dev_t dev, struct aio_req *aio, cred_t *credp);
149int  (*cb_awrite)(dev_t dev, struct aio_req *aio, cred_t *credp);
150.Ed
151.Sh SEE ALSO
152.Xr aread 9E ,
153.Xr awrite 9E ,
154.Xr chpoll 9E ,
155.Xr close 9E ,
156.Xr dump 9E ,
157.Xr ioctl 9E ,
158.Xr mmap 9E ,
159.Xr open 9E ,
160.Xr print 9E ,
161.Xr prop_op 9E ,
162.Xr read 9E ,
163.Xr segmap 9E ,
164.Xr strategy 9E ,
165.Xr write 9E ,
166.Xr nochpoll 9F ,
167.Xr nodev 9F ,
168.Xr nulldev 9F ,
169.Xr dev_ops 9S ,
170.Xr qinit 9S
171.Rs
172.%T Writing Device Drivers
173.Re
174.Rs
175.%T STREAMS Programming Guide
176.Re
177