Hi All,
the aim of this patches set is to provide support for a BTRFS raid5/6 filesystem in GRUB. The first patch, implements the basic support for raid5/6. I.e this works when all the disks are present. The next 5 patches, are preparatory ones. The 7th patch implements the raid5 recovery for btrfs (i.e. handling the disappearing of 1 disk). The 8th patch makes the code for handling the raid6 recovery more generic. The last one implements the raid6 recovery for btrfs (i.e. handling the disappearing up to two disks). I tested the code in grub-emu, and it works both with all the disks, and with some disks missing. I checked the crc32 calculated from grub and from linux and these matched. Finally I checked if the support for md raid6 still works properly, and it does (with all drives and with up to 2 drives missing) Comments are welcome. Changelog v1: initial support for btrfs raid5/6. No recovery allowed v2: full support for btrfs raid5/6. Recovery allowed v3: some minor cleanup suggested by Daniel Kiper; reusing the original raid6 recovery code of grub v4: Several spell fix; better description of the RAID layout in btrfs, and the variables which describes the stripe positioning; split the patch #5 in two (#5 and #6) v5: Several spell fix; improved code comment in patch #1, small clean up in the code v6: Small cleanup; improved the wording in the RAID6 layout description; in the function raid6_recover_read_buffer() avoid a unnecessary memcpy in case of invalid data; v7: - patch 2,3,5,6,8 received an Review-by Daniel, and were unchanged from the last time (only minor cleanup in the commit description requested by Daniel) - patch 7 received some small update rearranging a for(), and some bracket around if() - patch 4, received an update message which explains better why NULL is stored in data->devices_attached[] - patch 9, received a blank line to separate better a code line from a previous comment. A description of 'parities_pos' was added - patch 1, received a major update about the variable meaning description in the comment. However I suspect that we need some further review to reach a fully agreement about this text. NB: the update are relate only to comments v8: - patch 2,5,6,8 received an Review-by Daniel, and were unchanged from the last time (only minor cleanup in the commit description requested by Daniel) - patch 1 received some adjustement to the variables description due to the different terminology between BTRFS and other RAID implementatio. Added a description for the "nparities" variable. - patch 3 removed some unnecessary curly brackets (change request by Daniel) - patch 4 received an improved commit description about why and how the function find_device() is changed - patch 7 received an update which transforms a i = 0; while(i..) i++; in for( i = 0..... ; i++); - patch 9 received an update to the comment v9: - patch 1: update comments - patch 4: update commit messages - patch 7: added a comment about accessing an array of structs after another structs; changed if(err == GRUB_ERR_NONE) in if(!err) changed if(err != GRUB_ERR_NONE) in if(err) BR G.Baroncelli -- gpg @keyserver.linux.it: Goffredo Baroncelli <kreijackATinwind.it> Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5 _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel