24b034a69e
~forever. This requires a number of things:
1) If we can't create a DAG, set desc->numStripes to 0 in
rf_SelectAlgorithm. This will ensure that we don't attempt to free
any dagArray[] elements in rf_StateCleanup.
2) Modify rf_State_CreateDAG() to not panic in the event of a DAG
failure. Instead, set the bp->b_flags and bp->b_error, and set things
up to skip to rf_State_Cleanup().
3) Need to mark desc->status as "bad" so that we actually stop looking
for a different DAG. (which we won't find... no matter how many times
we try).
4) rf_State_LastState() will then do the biodone(), and return EIO for
the IO in question.
5) Remove some " || 1 "'s from ProcessNode(). These were for
debugging, and we don't need the failure notices spewing
over and over again as the failing DAGs are processed.
6) Needed to change
if (asmap->numDataFailed + asmap->numParityFailed > 1)
to
if ((asmap->numDataFailed + asmap->numParityFailed > 1) ||
(raidPtr->numFailures > 1)){
in rf_raid5.c so that it doesn't try to return
rf_CreateNonRedundantWriteDAG as the creation function.
7) Note that we can't apply the above change to the RAID 1 code as
with the silly "fake 2-D" RAID 1 sets, it is possible to have 2 failed
components in the RAID 1 set, and that would stop them from working.
(I really don't know why/how those "fake 2-D" RAID 1 sets even work
with all the "single-fault" assumptions present in the rest of the
code.)
8) Needed to protect rf_RAID0DagSelect() in a similar way -- it should
return NULL as the createFunc.
9) No point printing out "Multiple disks failed..." a zillion times.