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1da177e4 LT |
1 | /* |
2 | * This file is subject to the terms and conditions of the GNU General Public | |
3 | * License. See the file "COPYING" in the main directory of this archive | |
4 | * for more details. | |
5 | * | |
6 | * Copyright (C) 1995, 96, 99, 2001 Ralf Baechle | |
7 | */ | |
8 | #ifndef _ASM_IOCTL_H | |
9 | #define _ASM_IOCTL_H | |
10 | ||
11 | /* | |
12 | * The original linux ioctl numbering scheme was just a general | |
13 | * "anything goes" setup, where more or less random numbers were | |
14 | * assigned. Sorry, I was clueless when I started out on this. | |
15 | * | |
16 | * On the alpha, we'll try to clean it up a bit, using a more sane | |
17 | * ioctl numbering, and also trying to be compatible with OSF/1 in | |
18 | * the process. I'd like to clean it up for the i386 as well, but | |
19 | * it's so painful recognizing both the new and the old numbers.. | |
20 | * | |
21 | * The same applies for for the MIPS ABI; in fact even the macros | |
22 | * from Linux/Alpha fit almost perfectly. | |
23 | */ | |
24 | ||
25 | #define _IOC_NRBITS 8 | |
26 | #define _IOC_TYPEBITS 8 | |
27 | #define _IOC_SIZEBITS 13 | |
28 | #define _IOC_DIRBITS 3 | |
29 | ||
30 | #define _IOC_NRMASK ((1 << _IOC_NRBITS)-1) | |
31 | #define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1) | |
32 | #define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1) | |
33 | #define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1) | |
34 | ||
35 | #define _IOC_NRSHIFT 0 | |
36 | #define _IOC_TYPESHIFT (_IOC_NRSHIFT+_IOC_NRBITS) | |
37 | #define _IOC_SIZESHIFT (_IOC_TYPESHIFT+_IOC_TYPEBITS) | |
38 | #define _IOC_DIRSHIFT (_IOC_SIZESHIFT+_IOC_SIZEBITS) | |
39 | ||
1da177e4 LT |
40 | /* |
41 | * Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit. | |
42 | * And this turns out useful to catch old ioctl numbers in header | |
43 | * files for us. | |
44 | */ | |
45 | #define _IOC_NONE 1U | |
46 | #define _IOC_READ 2U | |
47 | #define _IOC_WRITE 4U | |
48 | ||
49 | /* | |
50 | * The following are included for compatibility | |
51 | */ | |
52 | #define _IOC_VOID 0x20000000 | |
53 | #define _IOC_OUT 0x40000000 | |
54 | #define _IOC_IN 0x80000000 | |
55 | #define _IOC_INOUT (IOC_IN|IOC_OUT) | |
56 | ||
21a151d8 | 57 | #define _IOC(dir, type, nr, size) \ |
1da177e4 LT |
58 | (((dir) << _IOC_DIRSHIFT) | \ |
59 | ((type) << _IOC_TYPESHIFT) | \ | |
60 | ((nr) << _IOC_NRSHIFT) | \ | |
61 | ((size) << _IOC_SIZESHIFT)) | |
62 | ||
63 | /* provoke compile error for invalid uses of size argument */ | |
64 | extern unsigned int __invalid_size_argument_for_IOC; | |
65 | #define _IOC_TYPECHECK(t) \ | |
66 | ((sizeof(t) == sizeof(t[1]) && \ | |
67 | sizeof(t) < (1 << _IOC_SIZEBITS)) ? \ | |
68 | sizeof(t) : __invalid_size_argument_for_IOC) | |
69 | ||
70 | /* used to create numbers */ | |
21a151d8 RB |
71 | #define _IO(type, nr) _IOC(_IOC_NONE, (type), (nr), 0) |
72 | #define _IOR(type, nr, size) _IOC(_IOC_READ, (type), (nr), (_IOC_TYPECHECK(size))) | |
73 | #define _IOW(type, nr, size) _IOC(_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size))) | |
74 | #define _IOWR(type, nr, size) _IOC(_IOC_READ|_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size))) | |
75 | #define _IOR_BAD(type, nr, size) _IOC(_IOC_READ, (type), (nr), sizeof(size)) | |
76 | #define _IOW_BAD(type, nr, size) _IOC(_IOC_WRITE, (type), (nr), sizeof(size)) | |
77 | #define _IOWR_BAD(type, nr, size) _IOC(_IOC_READ|_IOC_WRITE, (type), (nr), sizeof(size)) | |
1da177e4 LT |
78 | |
79 | ||
80 | /* used to decode them.. */ | |
81 | #define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK) | |
82 | #define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK) | |
83 | #define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK) | |
84 | #define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK) | |
85 | ||
86 | /* ...and for the drivers/sound files... */ | |
87 | ||
88 | #define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT) | |
89 | #define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT) | |
90 | #define IOC_INOUT ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT) | |
91 | #define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT) | |
92 | #define IOCSIZE_SHIFT (_IOC_SIZESHIFT) | |
93 | ||
94 | #endif /* _ASM_IOCTL_H */ |