Martchus
/
mdadm
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Allow creation of a RAID6 with a single missing device. 

This did not work before as we couldn't mark it clean as there would
be some parity blocks out of sync, and raid6 will not assemble a
dirty degraded array.
So make such arrays doubly degraded (the last device becomes a spare)
and clean.
This commit is contained in:
Neil Brown 2008-04-28 16:30:09 +10:00
parent 3cdfb6a712
commit 6fb79233b0
2 changed files with 19 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
ChangeLog
View File

@ -6,6 +6,7 @@ Changes Prior to this release
- For v0.90 superblocks, print the 'Events' count as a real count,
not 2 numbers separated by a dot.
- Updates some URLs in the man page.
- Allow creation of a RAID6 with exactly one missing device.
Changes Prior to 2.6.4 release
- Make "--create --auto=mdp" work for non-standard device names.

20
Create.c
View File

@ -63,6 +63,7 @@ int Create(struct supertype *st, char *mddev, int mdfd,
int fail=0, warn=0;
struct stat stb;
int first_missing = subdevs * 2;
int second_missing = subdevs * 2;
int missing_disks = 0;
int insert_point = subdevs * 2; /* where to insert a missing drive */
int pass;
@ -203,6 +204,8 @@ int Create(struct supertype *st, char *mddev, int mdfd,
if (strcasecmp(dname, "missing")==0) {
if (first_missing > dnum)
first_missing = dnum;
if (second_missing > dnum && dnum > first_missing)
second_missing = dnum;
missing_disks ++;
continue;
}
@ -341,6 +344,18 @@ int Create(struct supertype *st, char *mddev, int mdfd,
break;
}
}
/* For raid6, if creating with 1 missing drive, make a good drive
* into a spare, else the create will fail
*/
if (assume_clean == 0 && force == 0 && first_missing < raiddisks &&
second_missing >= raiddisks && level == 6) {
insert_point = raiddisks - 1;
if (insert_point == first_missing)
insert_point--;
sparedisks ++;
info.array.active_disks--;
missing_disks++;
}
if (level <= 0 && first_missing != subdevs * 2) {
fprintf(stderr,
@ -360,11 +375,12 @@ int Create(struct supertype *st, char *mddev, int mdfd,
if (fstat(mdfd, &stb)==0)
info.array.md_minor = minor(stb.st_rdev);
info.array.not_persistent = 0;
/*** FIX: Need to do something about RAID-6 here ***/
if ( ( (level == 4 || level == 5) &&
(insert_point < raiddisks || first_missing < raiddisks) )
||
( level == 6 && missing_disks == 2)
( level == 6 && (insert_point < raiddisks
|| second_missing < raiddisks))
||
assume_clean
)