Commit Graph

3 Commits

Author SHA1 Message Date
Laura Abbott
c6517b7815 doc: ioctl: Add some clarifications to botching-up-ioctls
- The guide currently says to pad the structure to a multiple of
  64-bits. This is not necessary in cases where the structure contains
  no 64-bit types. Clarify this concept to avoid unnecessary padding.
- When using __u64 to hold user pointers, blindly trying to do a cast to
  a void __user * may generate a warning on 32-bit systems about a cast
  from an integer to a pointer of different size. There is a macro to
  deal with this which hides an ugly double cast. Add a reference to
  this macro.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-09-06 06:00:22 -06:00
Masanari Iida
d53a7b8ff6 Doc: ioctl: Fix typos in Documentation/ioctl
This patch fix some spelling typos in Documentation/ioctl.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-11-20 16:52:50 -07:00
Michael Ellerman
efe4a77221 Documentation: add How to avoid botching up ioctls
I pointed some folks at this and they wondered why it wasn't in the
kernel Documentation directory. So now it is.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-09 09:13:40 -07:00