This removes the internal ide-cd buffer and falls back to read-ahead block layer
capabilities. Thorough testing (cd burning, dvd read, raw read) gives with the
bufferless mode marginally better performance in addition to simplified code.
bufferless:
dd: reading `/dev/hdc': Input/output error
6238+0 records in
6238+0 records out
204406784 bytes (204 MB) copied, 259.891 s, 787 kB/s
real 4m21.598s
user 0m0.014s
sys 0m0.744s
with the old buffer (2.6.25-rc1):
dd: reading `/dev/hdc': Input/output error
6238+0 records in
6238+0 records out
204406784 bytes (204 MB) copied, 262.893 s, 778 kB/s
real 4m22.938s
user 0m0.009s
sys 0m0.771s
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
968c496413