Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r256448, r257029;

Make di_blocks unsigned in UFS1 as is the case already for UFS2.
Most of the code between UFS1 and UFS2 is shared so this change
is pretty safe. Not only this makes UFS1 and 2 consistent but it
also matches what NetBSD and MacOS X have for some years now.

UFS2: make di_extsize unsigned.
di_extsize is the EA size and as such it should be unsigned.
Adjust related types for consistency.

Reviewed by: mckusick

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

When running with the -d option, instrument fsck_ffs to track the number,
data type, and running time of its I/O operations.

No functional changes.

Mechanical whitespace cleanup.

MFC after: 3 weeks

Use __FBSDID() to quiet GCC 3.3 warnings.

Add a source file where EXTATTR checks will happen and hook it in even
if it doesn't do anything yet.

Sponsored by: DARPA & NAI Labs.