patch-1.3.22 linux/include/asm-i386/ioctl.h

• Lines: 89
• Date: Tue Aug 29 10:15:53 1995
• Orig file: v1.3.21/linux/include/asm-i386/ioctl.h
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.21/linux/include/asm-i386/ioctl.h linux/include/asm-i386/ioctl.h
@@ -0,0 +1,88 @@
+/* $Id: ioctl.h,v 1.5 1993/07/19 21:53:50 root Exp root $
+ *
+ * linux/ioctl.h for Linux by H.H. Bergman.
+ */
+
+#ifndef _ASMI386_IOCTL_H
+#define _ASMI386_IOCTL_H
+
+#include <asm/page.h>		/* for PAGE_SIZE */
+
+/* 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 !
+ */
+
+#define IOC_VOID	0x00000000	/* param in size field */
+#define IOC_IN		0x40000000	/* user --> kernel */
+#define IOC_OUT		0x80000000	/* kernel --> user */
+#define IOC_INOUT	(IOC_IN | IOC_OUT)	/* both */
+#define IOCSIZE_MASK	0x3fff0000	/* size (max 16k-1 bytes) */
+#define IOCSIZE_SHIFT	16		/* how to get the size */
+#define IOCSIZE_MAX	((PAGE_SIZE-1)&(IOCSIZE_MASK >> IOCSIZE_SHIFT))
+#define IOCCMD_MASK	0x0000ffff	/* command code */
+#define IOCCMD_SHIFT	0
+#define IOCPARM_MASK IOCCMD_MASK
+#define IOCPARM_SHIFT IOCCMD_SHIFT
+
+#define IOC_SIZE(cmd)	(((cmd) & IOCSIZE_MASK) >> IOCSIZE_SHIFT)
+#define IOCBASECMD(cmd)	((cmd) & ~IOCPARM_MASK)
+#define IOCGROUP(cmd)	(((cmd) >> 8) & 0xFF)
+
+/* _IO(magic, subcode); size field is zero and the 
+ * subcode determines the command.
+ */
+#define _IO(c,d)	(IOC_VOID | ((c)<<8) | (d)) /* param encoded */
+
+/* _IOXX(magic, subcode, arg_t); where arg_t is the type of the
+ * (last) argument field in the ioctl call, if present.
+ */
+#define _IOW(c,d,t)	(IOC_IN | ((sizeof(t)<<16) & IOCSIZE_MASK) | \
+				  ((c)<<8) | (d))
+#define _IOR(c,d,t)	(IOC_OUT | ((sizeof(t)<<16) & IOCSIZE_MASK) | \
+				   ((c)<<8) | (d))
+/* WR rather than RW to avoid conflict with stdio.h */
+#define _IOWR(c,d,t)	(IOC_INOUT | ((sizeof(t)<<16) & IOCSIZE_MASK) | \
+				     ((c)<<8) | (d))
+
+/*
+ * 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_READ	1U
+#define _IOC_WRITE	2U
+
+/* used to decode ioctl numbers.. */
+#define _IOC_DIR(nr)		(((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
+#define _IOC_NR(nr)		(((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
+#define _IOC_SIZE(nr)		(((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
+
+#endif /* _ASMI386_IOCTL_H */