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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-09 15:58:38 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-09 15:58:38 +0900
commit50e0d10232db05c6776afcf6098459bff47e8b15 (patch)
tree0e89971de6d960c8946cc9351d73b297347a0260 /include/uapi/asm-generic/ioctl.h
parent8711798772641b2f593beebebcab5b1ec2309f0c (diff)
parentc37d6154c0b9163c27e53cc1d0be3867b4abd760 (diff)
Merge tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic updates from Arnd Bergmann: "This has three changes for asm-generic that did not really fit into any other branch as normal asm-generic changes do. One is a fix for a build warning, the other two are more interesting: * A patch from Mark Brown to allow using the common clock infrastructure on all architectures, so we can use the clock API in architecture independent device drivers. * The UAPI split patches from David Howells for the asm-generic files. There are other architecture specific series that are going through the arch maintainer tree and that depend on this one. There may be a few small merge conflicts between Mark's patch and the following arch header file split patches. In each case the solution will be to keep the new "generic-y += clkdev.h" line, even if it ends up being the only line in the Kbuild file." * tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: UAPI: (Scripted) Disintegrate include/asm-generic asm-generic: Add default clkdev.h asm-generic: xor: mark static functions as __maybe_unused
Diffstat (limited to 'include/uapi/asm-generic/ioctl.h')
-rw-r--r--include/uapi/asm-generic/ioctl.h98
1 files changed, 98 insertions, 0 deletions
diff --git a/include/uapi/asm-generic/ioctl.h b/include/uapi/asm-generic/ioctl.h
new file mode 100644
index 00000000000..7e7c11b5214
--- /dev/null
+++ b/include/uapi/asm-generic/ioctl.h
@@ -0,0 +1,98 @@
+#ifndef _UAPI_ASM_GENERIC_IOCTL_H
+#define _UAPI_ASM_GENERIC_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 !
+ */
+
+/*
+ * The following is for compatibility across the various Linux
+ * platforms. The generic 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
+
+/*
+ * Let any architecture override either of the following before
+ * including this file.
+ */
+
+#ifndef _IOC_SIZEBITS
+# define _IOC_SIZEBITS 14
+#endif
+
+#ifndef _IOC_DIRBITS
+# define _IOC_DIRBITS 2
+#endif
+
+#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, which any architecture can choose to override
+ * before including this file.
+ */
+
+#ifndef _IOC_NONE
+# define _IOC_NONE 0U
+#endif
+
+#ifndef _IOC_WRITE
+# define _IOC_WRITE 1U
+#endif
+
+#ifndef _IOC_READ
+# define _IOC_READ 2U
+#endif
+
+#define _IOC(dir,type,nr,size) \
+ (((dir) << _IOC_DIRSHIFT) | \
+ ((type) << _IOC_TYPESHIFT) | \
+ ((nr) << _IOC_NRSHIFT) | \
+ ((size) << _IOC_SIZESHIFT))
+
+#ifndef __KERNEL__
+#define _IOC_TYPECHECK(t) (sizeof(t))
+#endif
+
+/* used to create numbers */
+#define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0)
+#define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),(_IOC_TYPECHECK(size)))
+#define _IOW(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),(_IOC_TYPECHECK(size)))
+#define _IOWR(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),(_IOC_TYPECHECK(size)))
+#define _IOR_BAD(type,nr,size) _IOC(_IOC_READ,(type),(nr),sizeof(size))
+#define _IOW_BAD(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
+#define _IOWR_BAD(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 /* _UAPI_ASM_GENERIC_IOCTL_H */