On 9/10/20 1:17 AM, Zdenek Kabelac wrote:
Dne 09. 09. 20 v 18:47 Zhao Heming napsal(a):
report LV is usable for upper layer.
leave issues
- this patch doesn't contain dm table comparison. So if the disk
is removed then re-inserted, but the re-inserted disk
major:minor is changed, the code doesn't have ability to detect.
- raid10: removing any 2 disks will think as array broken.
Signed-off-by: Zhao Heming <heming.zhao@xxxxxxxx>
---
v2:
- remove dm table parsing code in _lv_is_usable()
- add new status bit NOT_USABLE_LV.
note, I chose the first available bit 0x0000000080000000
- _lvusable_disp() uses lv_is_usable() to return usable status
dm_list_iterate_items(lvseg, &lv->segments) {
for (s = 0; s < lvseg->area_count; ++s) {
if (seg_type(lvseg, s) == AREA_PV) {
- if (is_missing_pv(seg_pv(lvseg, s)))
+ pv = seg_pv(lvseg, s);
+ if (!(pv->dev) && is_missing_pv(pv)) {
lv->status |= PARTIAL_LV;
+ lv->status |= NOT_USABLE_LV;
+ }
}
}
}
Hi
As it can be seen here - there is big intersection with meaning of
PARTIAL_LV.
And the question is - what does it mean in the context of various segment
types.
I believe we need to discuss with Heinz - whether we want to mark
Raid LVs partial in case they are actually 'only leg-pertial' and should
be actually activatable without partial activation - which is ATM abused for this purpose.
ATM I'm not sure we want to introduce new flags, which has only slight
deviation from current partial flag - which should deserve closer look
of its meaning.
We'll try to find something with Heinz to agree with.
Ok, wait for feedback from Heinz.
I agree with you. the PARTIAL_LV is more closer to the new bit NOT_USABLE_LV.
There is another bit MISSING_PV, which is set when pv is missing or the pv is not workable.
From my understanding, we could reuse the PARTIAL_LV to show different meaning according to different context. For example, in raid env, the top layer LV will be set PARTIAL_LV when the raid array not usable (e.g. raid0 missing a disk). Other cases, within raid limit, top layer raid LV won't be set. if following the rule, there will no need to set the new bit NOT_USABLE_LV.
Heming
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