question about:raid1 fix_read_error

Hi,Neil
I readed the code of raid1:fix_read_error().I find some problem:
1:In order to find other correct data, your code only judge :

				rdev &&
			    test_bit(In_sync, &rdev->flags) &&
			    is_badblock(rdev, sect, s,
					&first_bad, &bad_sectors) == 0 &&
			    sync_page_io(rdev, sect, s<<9,
					 conf->tmppage, READ, false))
 	But the spare disk which is woring ? you can use spare disk is read_balance().
	If you can using spare disk why you set bad blocks?
2: about set bad blocks,when did not find correct data.
	You only:
	struct md_rdev *rdev = conf->mirrors[read_disk].rdev;
			if (!rdev_set_badblocks(rdev, sect, s, 0))
				md_error(mddev, rdev);
	But the other disks which you try to find.
	If you did not set all disks,then in read_balance will read other disk which call in fix_read_error.But the result is the same,
	read error and  set badsectors.

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majianpeng
2012-04-11