Hi,
在 2025/09/02 20:25, John Garry 写道:
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 408c26398321..35c6498b4917 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -3211,6 +3211,7 @@ static int raid1_set_limits(struct mddev *mddev)
md_init_stacking_limits(&lim);
lim.max_write_zeroes_sectors = 0;
+ lim.max_hw_wzeroes_unmap_sectors = 0;
It would be better if we documented why we cannot support this on
raid1/10, yet we can on raid0.
I am looking through the history of why max_write_zeroes_sectors is set
to zero. I have gone as far back as 5026d7a9b, and this tells us that
the retry mechanism for WRITE SAME causes an issue where mirrors are
offlined (and so we disabled the support); and this was simply copied
for write zeroes in 3deff1a70.
Yes, we don't support it for now, and I think it is not too hard to
support write zeros, and finaly to support unmap zeros. BTW, raid5
discard is in the same suituation.
However, I feel this is not related to this set, perhaps a seperate
patch to add comments, I can accept that.
Thanks,
Kuai
