K 10
svn:author
V 6
karels
K 8
svn:date
V 27
2023-08-18T12:42:09.743394Z
K 7
svn:log
V 770
md driver compat32: fix structure padding for arm, powerpc

Because the 32-bit md_ioctl structure contains 64-bit members, arm
and powerpc add padding to a multiple of 8.  i386 doesn't do this.
The md_ioctl32 definition was correct for amd64/i386 without padding,
but wrong for arm64 and powerpc64.  Make __packed__ conditional on
__amd64__, and test for the expected size on non-amd64.  Note that
mdconfig is used in the ATF test suite.  Note, I verified the
structure size for powerpc, but was unable to test.

Reviewed by:	jrtc27
Differential Revision:	https://reviews.freebsd.org/D41339
Discussed with:	jhibbits

(cherry picked from commit 58a46cfd751ac726ddca8544bf73a290b0154a57)

Git Hash:   55b79ced0048e9015053ccfd96cf7f38be49ecbf
Git Author: karels@FreeBSD.org
END