5 * Our DIR and SIZE overlap in order to simulteneously provide
6 * a non-zero _IOC_NONE (for binary compatibility) and
7 * 14 bits of size as on i386. Here's the layout:
10 * 0x80000000 DIR = WRITE
11 * 0x40000000 DIR = READ
12 * 0x20000000 DIR = NONE
13 * 0x3FFF0000 SIZE (overlaps NONE bit)
19 #define _IOC_TYPEBITS 8
20 #define _IOC_SIZEBITS 13 /* Actually 14, see below. */
21 #define _IOC_DIRBITS 3
23 #define _IOC_NRMASK ((1 << _IOC_NRBITS)-1)
24 #define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1)
25 #define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1)
26 #define _IOC_XSIZEMASK ((1 << (_IOC_SIZEBITS+1))-1)
27 #define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1)
29 #define _IOC_NRSHIFT 0
30 #define _IOC_TYPESHIFT (_IOC_NRSHIFT + _IOC_NRBITS)
31 #define _IOC_SIZESHIFT (_IOC_TYPESHIFT + _IOC_TYPEBITS)
32 #define _IOC_DIRSHIFT (_IOC_SIZESHIFT + _IOC_SIZEBITS)
38 #define _IOC(dir,type,nr,size) \
39 (((dir) << _IOC_DIRSHIFT) | \
40 ((type) << _IOC_TYPESHIFT) | \
41 ((nr) << _IOC_NRSHIFT) | \
42 ((size) << _IOC_SIZESHIFT))
44 #define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0)
45 #define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),sizeof(size))
46 #define _IOW(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
47 #define _IOWR(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size))
49 /* Used to decode ioctl numbers in drivers despite the leading underscore... */
50 #define _IOC_DIR(nr) \
51 ( (((((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK) & (_IOC_WRITE|_IOC_READ)) != 0)? \
52 (((nr) >> _IOC_DIRSHIFT) & (_IOC_WRITE|_IOC_READ)): \
53 (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK) )
54 #define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
55 #define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
56 #define _IOC_SIZE(nr) \
57 ((((((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK) & (_IOC_WRITE|_IOC_READ)) == 0)? \
58 0: (((nr) >> _IOC_SIZESHIFT) & _IOC_XSIZEMASK))
60 /* ...and for the PCMCIA and sound. */
61 #define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT)
62 #define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT)
63 #define IOC_INOUT ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
64 #define IOCSIZE_MASK (_IOC_XSIZEMASK << _IOC_SIZESHIFT)
65 #define IOCSIZE_SHIFT (_IOC_SIZESHIFT)
67 #endif /* !(_SPARC_IOCTL_H) */