user/sven/linux.git/include/uapi/linux/blkpg.h, branch v4.9.33Linux Kernel
https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.9.332015-09-29T20:37:04Zmtd: provide proper 32/64-bit compat_ioctl() support for BLKPG2015-09-29T20:37:04ZBrian Norriscomputersforpeace@gmail.com2015-09-21T20:26:59Zurn:sha1:53bb724f94f57b67213e08a4c155c8c5eb74c644
After a bit of poking around wondering why my 32-bit user-space can't
seem to send a proper ioctl(BLKPG) to an MTD on my 64-bit kernel
(ARM64), I noticed that struct blkpg_ioctl_arg is actually pretty
unsuitable for use in the ioctl() ABI, due to its use of raw pointers,
and its lack of alignment/packing restrictions (32-bit arch'es tend to
pack the 4 fields into 4 32-bit words, whereas 64-bit arch'es would add
padding after the third int, and make this 6 32-bit words).
Anyway, this means BLKPG deserves some special compat_ioctl handling. Do
the conversion in a small shim for MTD.
block/compat_ioctl.c already has compat support for the block subsystem,
but it does so by a re-marshalling data to/from user-space (see
compat_blkpg_ioctl()). Personally, I think this approach is cleaner.
Tested only on MTD, with an ARM32 user space on an ARM64 kernel.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
UAPI: (Scripted) Disintegrate include/linux2012-10-13T09:46:48ZDavid Howellsdhowells@redhat.com2012-10-13T09:46:48Zurn:sha1:607ca46e97a1b6594b29647d98a32d545c24bdff
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>