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Diffstat (limited to 'include/asm-m68k/ioctl.h')
| -rw-r--r-- | include/asm-m68k/ioctl.h | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/include/asm-m68k/ioctl.h b/include/asm-m68k/ioctl.h new file mode 100644 index 000000000000..fd68914ab292 --- /dev/null +++ b/include/asm-m68k/ioctl.h @@ -0,0 +1,80 @@ +/* $Id: ioctl.h,v 1.3 1997/04/16 15:10:07 jes Exp $ + * + * linux/ioctl.h for Linux by H.H. Bergman. + */ + +#ifndef _M68K_IOCTL_H +#define _M68K_IOCTL_H + +/* ioctl command encoding: 32 bits total, command in lower 16 bits, + * size of the parameter structure in the lower 14 bits of the + * upper 16 bits. + * Encoding the size of the parameter structure in the ioctl request + * is useful for catching programs compiled with old versions + * and to avoid overwriting user space outside the user buffer area. + * The highest 2 bits are reserved for indicating the ``access mode''. + * NOTE: This limits the max parameter size to 16kB -1 ! + */ + +/* + * I don't really have any idea about what this should look like, so + * for the time being, this is heavily based on the PC definitions. + */ + +/* + * The following is for compatibility across the various Linux + * platforms. The i386 ioctl numbering scheme doesn't really enforce + * a type field. De facto, however, the top 8 bits of the lower 16 + * bits are indeed used as a type field, so we might just as well make + * this explicit here. Please be sure to use the decoding macros + * below from now on. + */ +#define _IOC_NRBITS 8 +#define _IOC_TYPEBITS 8 +#define _IOC_SIZEBITS 14 +#define _IOC_DIRBITS 2 + +#define _IOC_NRMASK ((1 << _IOC_NRBITS)-1) +#define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1) +#define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1) +#define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1) + +#define _IOC_NRSHIFT 0 +#define _IOC_TYPESHIFT (_IOC_NRSHIFT+_IOC_NRBITS) +#define _IOC_SIZESHIFT (_IOC_TYPESHIFT+_IOC_TYPEBITS) +#define _IOC_DIRSHIFT (_IOC_SIZESHIFT+_IOC_SIZEBITS) + +/* + * Direction bits. + */ +#define _IOC_NONE 0U +#define _IOC_WRITE 1U +#define _IOC_READ 2U + +#define _IOC(dir,type,nr,size) \ + (((dir) << _IOC_DIRSHIFT) | \ + ((type) << _IOC_TYPESHIFT) | \ + ((nr) << _IOC_NRSHIFT) | \ + ((size) << _IOC_SIZESHIFT)) + +/* used to create numbers */ +#define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0) +#define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),sizeof(size)) +#define _IOW(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),sizeof(size)) +#define _IOWR(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size)) + +/* used to decode ioctl numbers.. */ +#define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK) +#define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK) +#define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK) +#define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK) + +/* ...and for the drivers/sound files... */ + +#define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT) +#define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT) +#define IOC_INOUT ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT) +#define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT) +#define IOCSIZE_SHIFT (_IOC_SIZESHIFT) + +#endif /* _M68K_IOCTL_H */ |