Add the RAID 6 recovery, in order to use a RAID 6 filesystem even if some
disks (up to two) are missing. This code use the md RAID 6 code already
present in grub.
Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The original code which handles the recovery of a RAID 6 disks array
assumes that all reads are multiple of 1 << GRUB_DISK_SECTOR_BITS and it
assumes that all the I/O is done via the struct grub_diskfilter_segment.
This is not true for the btrfs code. In order to reuse the native
grub_raid6_recover() code, it is modified to not call
grub_diskfilter_read_node() directly, but to call an handler passed
as an argument.
Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Add support for recovery for a RAID 5 btrfs profile. In addition
it is added some code as preparatory work for RAID 6 recovery code.
Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Move the code in charge to read the data from disk into a separate
function. This helps to separate the error handling logic (which
depends on the different raid profiles) from the read from disk
logic. Refactoring this code increases the general readability too.
This is a preparatory patch, to help the adding of the RAID 5/6 recovery code.
Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
A portion of the logging code is moved outside of internal for(;;). The part
that is left inside is the one which depends on the internal for(;;) index.
This is a preparatory patch. The next one will refactor the code inside
the for(;;) into an another function.
Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Currently read from missing device triggers rescan. However, it is never
recorded that the device is missing. So, each read of a missing device
triggers rescan again and again. This behavior causes a lot of unneeded
rescans leading to huge slowdowns.
This patch fixes above mentioned issue. Information about missing devices
is stored in the data->devices_attached[] array as NULL value in dev
member. Rescan is triggered only if no information is found for a given
device. This means that only first time read triggers rescan.
The patch drops premature return. This way data->devices_attached[] is
filled even when a given device is missing.
Signed-off-by: Goffredo Baroncelli <kreikack@inwind.it>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The caller knows better if this error is fatal or not, i.e. another disk is
available or not.
This is a preparatory patch.
Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This helper is used in a few places to help the debugging. As
conservative approach the error is only logged.
This does not impact the error handling.
Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Goffredo Baroncelli