diff options
Diffstat (limited to 'include/asm-alpha/ioctl.h')
-rw-r--r-- | include/asm-alpha/ioctl.h | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/include/asm-alpha/ioctl.h b/include/asm-alpha/ioctl.h new file mode 100644 index 000000000000..fc63727f4178 --- /dev/null +++ b/include/asm-alpha/ioctl.h @@ -0,0 +1,66 @@ +#ifndef _ALPHA_IOCTL_H +#define _ALPHA_IOCTL_H + +/* + * The original linux ioctl numbering scheme was just a general + * "anything goes" setup, where more or less random numbers were + * assigned. Sorry, I was clueless when I started out on this. + * + * On the alpha, we'll try to clean it up a bit, using a more sane + * ioctl numbering, and also trying to be compatible with OSF/1 in + * the process. I'd like to clean it up for the i386 as well, but + * it's so painful recognizing both the new and the old numbers.. + */ + +#define _IOC_NRBITS 8 +#define _IOC_TYPEBITS 8 +#define _IOC_SIZEBITS 13 +#define _IOC_DIRBITS 3 + +#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 _IOC_NONE could be 0, but OSF/1 gives it a bit. + * And this turns out useful to catch old ioctl numbers in header + * files for us. + */ +#define _IOC_NONE 1U +#define _IOC_READ 2U +#define _IOC_WRITE 4U + +#define _IOC(dir,type,nr,size) \ + ((unsigned int) \ + (((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 them.. */ +#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 /* _ALPHA_IOCTL_H */ |