1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 3 #ifndef _OSAL_IOCTL_H 4 #define _OSAL_IOCTL_H 5 6 /* ioctl command encoding: 32 bits total, command in lower 16 bits, 7 * size of the parameter structure in the lower 14 bits of the 8 * upper 16 bits. 9 * Encoding the size of the parameter structure in the ioctl request 10 * is useful for catching programs compiled with old versions 11 * and to avoid overwriting user space outside the user buffer area. 12 * The highest 2 bits are reserved for indicating the ``access mode''. 13 * NOTE: This limits the max parameter size to 16kB -1 ! 14 */ 15 16 /* 17 * The following is for compatibility across the various Linux 18 * platforms. The generic ioctl numbering scheme doesn't really enforce 19 * a type field. De facto, however, the top 8 bits of the lower 16 20 * bits are indeed used as a type field, so we might just as well make 21 * this explicit here. Please be sure to use the decoding macros 22 * below from now on. 23 */ 24 #define _IOC_NRBITS 8 25 #define _IOC_TYPEBITS 8 26 27 /* 28 * Let any architecture override either of the following before 29 * including this file. 30 */ 31 #ifndef _IOC_SIZEBITS 32 #define _IOC_SIZEBITS 14 33 #endif 34 35 #ifndef _IOC_DIRBITS 36 #define _IOC_DIRBITS 2 37 #endif 38 39 #define _IOC_NRMASK ((1 << _IOC_NRBITS)-1) 40 #define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1) 41 #define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1) 42 #define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1) 43 44 #define _IOC_NRSHIFT 0 45 #define _IOC_TYPESHIFT (_IOC_NRSHIFT+_IOC_NRBITS) 46 #define _IOC_SIZESHIFT (_IOC_TYPESHIFT+_IOC_TYPEBITS) 47 #define _IOC_DIRSHIFT (_IOC_SIZESHIFT+_IOC_SIZEBITS) 48 49 /* 50 * Direction bits, which any architecture can choose to override 51 * before including this file. 52 */ 53 #ifndef _IOC_NONE 54 #define _IOC_NONE 0U 55 #endif 56 57 #ifndef _IOC_WRITE 58 #define _IOC_WRITE 1U 59 #endif 60 61 #ifndef _IOC_READ 62 #define _IOC_READ 2U 63 #endif 64 65 #define _IOC(dir, type, nr, size) \ 66 (((dir) << _IOC_DIRSHIFT) | \ 67 ((type) << _IOC_TYPESHIFT) | \ 68 ((nr) << _IOC_NRSHIFT) | \ 69 ((size) << _IOC_SIZESHIFT)) 70 71 #ifdef __CHECKER__ 72 #define _IOC_TYPECHECK(t) (sizeof(t)) 73 #else 74 #ifndef _IOC_TYPECHECK 75 /* provoke compile error for invalid uses of size argument */ 76 extern unsigned int __invalid_size_argument_for_IOC; 77 #define _IOC_TYPECHECK(t) \ 78 ((sizeof(t) == sizeof(t[1]) && \ 79 sizeof(t) < (1 << _IOC_SIZEBITS)) \ 80 ? sizeof(t) \ 81 : __invalid_size_argument_for_IOC) 82 #endif 83 #endif 84 85 /* used to create numbers */ 86 #define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0) 87 #define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),(_IOC_TYPECHECK(size))) 88 #define _IOW(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),(_IOC_TYPECHECK(size))) 89 #define _IOWR(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),(_IOC_TYPECHECK(size))) 90 #define _IOR_BAD(type,nr,size) _IOC(_IOC_READ,(type),(nr),sizeof(size)) 91 #define _IOW_BAD(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),sizeof(size)) 92 #define _IOWR_BAD(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size)) 93 94 /* used to decode ioctl numbers.. */ 95 #define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK) 96 #define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK) 97 #define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK) 98 #define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK) 99 100 #define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT) 101 #define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT) 102 #define IOC_INOUT ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT) 103 #define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT) 104 #define IOCSIZE_SHIFT (_IOC_SIZESHIFT) 105 106 #endif /* _OSAL_IOCTL_H */ 107