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 old md RAID 6 code already
present in grub.
Signed-off-by: Goffredo Baroncelli <kreij...@inwind.it>
---
grub-core/fs/btrfs.c | 45 +++++++++++++++++++++++++++++++++++++++-----
1 file changed, 40 insertions(+), 5 deletions(-)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 5fcaad86f..3d71b954e 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -30,6 +30,7 @@
#include <grub/i18n.h>
#include <grub/btrfs.h>
#include <grub/crypto.h>
+#include <grub/diskfilter.h>
GRUB_MOD_LICENSE ("GPLv3+");
@@ -695,11 +696,35 @@ rebuild_raid5 (struct raid56_buffer *buffers,
grub_uint64_t nstripes,
csize);
}
+static grub_err_t
+raid6_recover_read_buffer (void *data, int disk_nr,
+ grub_uint64_t addr __attribute__ ((unused)),
+ void *dest, grub_size_t size)
+{
+ struct raid56_buffer *buffers = data;
+
+ grub_memcpy(dest, buffers[disk_nr].buf, size);
+
+ grub_errno = buffers[disk_nr].data_is_valid ? GRUB_ERR_NONE :
+ GRUB_ERR_READ_ERROR;
+ return grub_errno;
+}
+
+static void
+rebuild_raid6 (struct raid56_buffer *buffers, grub_uint64_t nstripes,
+ grub_uint64_t csize, grub_uint64_t parities_pos, void *dest,
+ grub_uint64_t stripen)
+
+{
+ grub_raid6_recover_gen (buffers, nstripes, stripen, parities_pos,
+ dest, 0, csize, raid6_recover_read_buffer, 0);
+}
+
static grub_err_t
raid56_read_retry (struct grub_btrfs_data *data,
struct grub_btrfs_chunk_item *chunk,
grub_uint64_t stripe_offset, grub_uint64_t stripen,
- grub_uint64_t csize, void *buf)
+ grub_uint64_t csize, void *buf, grub_uint64_t parities_pos)
{
struct raid56_buffer *buffers = NULL;
@@ -780,6 +805,15 @@ raid56_read_retry (struct grub_btrfs_data *data,
ret = GRUB_ERR_READ_ERROR;
goto cleanup;
}
+ else if (failed_devices > 2 && (chunk_type & GRUB_BTRFS_CHUNK_TYPE_RAID6))
+ {
+ grub_dprintf ("btrfs",
+ "not enough disks for raid6: total %" PRIuGRUB_UINT64_T
+ ", missing %" PRIuGRUB_UINT64_T "\n",
+ nstripes, failed_devices);
+ ret = GRUB_ERR_READ_ERROR;
+ goto cleanup;
+ }
else
{
grub_dprintf ("btrfs",
@@ -796,7 +830,7 @@ raid56_read_retry (struct grub_btrfs_data *data,
}
else
{
- grub_dprintf ("btrfs", "called rebuild_raid6(), NOT IMPLEMENTED\n");
+ rebuild_raid6 (buffers, nstripes, csize, parities_pos, buf, stripen);
}
cleanup:
@@ -891,8 +925,9 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
int is_raid56;
grub_uint64_t parities_pos = 0;
- is_raid56 = !!(grub_le_to_cpu64 (chunk->type) &
- GRUB_BTRFS_CHUNK_TYPE_RAID5);
+ is_raid56 = !!(grub_le_to_cpu64 (chunk->type) &
+ (GRUB_BTRFS_CHUNK_TYPE_RAID5|
+ GRUB_BTRFS_CHUNK_TYPE_RAID6));
if (grub_le_to_cpu64 (chunk->size) <= off)
{
@@ -1089,7 +1124,7 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
csize, buf);
if (err != GRUB_ERR_NONE)
err = raid56_read_retry (data, chunk, stripe_offset,
- stripen, csize, buf);
+ stripen, csize, buf, parities_pos);
}
if (err == GRUB_ERR_NONE)
--
2.17.0
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