overall_stats: forward port to kernel 3.4+

by replacing deprecated functions with native add/sub for 64bit data types

Signed-off-by: faux123 <reioux@gmail.com>
Patch upstream to 3.4.11

Signed-off-by: Zarboz <zarboz@gmail.com>
Clean
Finishing 3.4.11 cleanup
Patching upstream 3.0.11->3.0.12

Signed-off-by: Zarboz <zarboz@gmail.com>
Patching upstream 3.4.12->3.4.13

Signed-off-by: Zarboz <zarboz@gmail.com>
3.4.13
Patching upstream 3.0.13->3.0.14

Signed-off-by: Zarboz <zarboz@gmail.com>
Patching upstream 3.4.14->3.4.15

Signed-off-by: Bryan Smith <zarboz@mint>
Patching upstream 3.4.15->3.4.16

Signed-off-by: Bryan Smith <zarboz@gmail.com>
patching upstream to 3.0.17

Signed-off-by: Bryan Smith <zarboz@gmail.com>

Signed-off-by: Bryan Smith <zarboz@gmail.com>
increasing readahead

Signed-off-by: Bryan Smith <zarboz@gmail.com>