UDF: alternate anchor block detection
From: Amit Sahrawat
Date: Mon Oct 03 2011 - 07:47:18 EST
While mounting UDF media, when the primary AVDP is not found at block
256, UDF code tries to read-in the alternate AVDP.
In the function udf_find_anchor, udf_scan_anchors is called 3 times,
where each call to udf_scan_anchors read 12 blocks.
In case there is no alternate AVDP stored, a total of 36 blocks are
read before mount fails - causing time delay for Mount Failure.
1) After first call to udf_scan_anchors and before the second call
there is varconv conversion, for the older drivers, which skips 7
blocks after every 32 blocks. What are these older drivers? Do we
still require this code?
2) After varconv conversion, why is there a third call to
udf_scan_anchors? In the 1st call and 3rd call to udf_scan_anchors,
exactly same blocks are read, so this 3rd call seems to be redundant.
I suggest this modified code for udf_find_anchor :-
lastblock = udf_scan_anchors(sb,udf_variable_to_fixed(sbi->s_last_block),fileset);
/* VARCONV didn't help. Clear it. */
Please share your opinion to the above '2' points.
Thanks & Regards,
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/