btrfs: Make more generic the code for RAID 6 rebuilding

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>
This commit is contained in:
Goffredo Baroncelli 2018-10-22 19:29:38 +02:00 committed by Daniel Kiper
parent 94854d9c3d
commit fa926cb4b4
2 changed files with 43 additions and 18 deletions

View file

@ -74,14 +74,26 @@ mod_255 (unsigned x)
}
static grub_err_t
grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
char *buf, grub_disk_addr_t sector, grub_size_t size)
raid6_recover_read_node (void *data, int disknr,
grub_uint64_t sector,
void *buf, grub_size_t size)
{
struct grub_diskfilter_segment *array = data;
return grub_diskfilter_read_node (&array->nodes[disknr],
(grub_disk_addr_t)sector,
size >> GRUB_DISK_SECTOR_BITS, buf);
}
grub_err_t
grub_raid6_recover_gen (void *data, grub_uint64_t nstripes, int disknr, int p,
char *buf, grub_uint64_t sector, grub_size_t size,
int layout, raid_recover_read_t read_func)
{
int i, q, pos;
int bad1 = -1, bad2 = -1;
char *pbuf = 0, *qbuf = 0;
size <<= GRUB_DISK_SECTOR_BITS;
pbuf = grub_zalloc (size);
if (!pbuf)
goto quit;
@ -91,17 +103,17 @@ grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
goto quit;
q = p + 1;
if (q == (int) array->node_count)
if (q == (int) nstripes)
q = 0;
pos = q + 1;
if (pos == (int) array->node_count)
if (pos == (int) nstripes)
pos = 0;
for (i = 0; i < (int) array->node_count - 2; i++)
for (i = 0; i < (int) nstripes - 2; i++)
{
int c;
if (array->layout & GRUB_RAID_LAYOUT_MUL_FROM_POS)
if (layout & GRUB_RAID_LAYOUT_MUL_FROM_POS)
c = pos;
else
c = i;
@ -109,8 +121,7 @@ grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
bad1 = c;
else
{
if (! grub_diskfilter_read_node (&array->nodes[pos], sector,
size >> GRUB_DISK_SECTOR_BITS, buf))
if (!read_func (data, pos, sector, buf, size))
{
grub_crypto_xor (pbuf, pbuf, buf, size);
grub_raid_block_mulx (c, buf, size);
@ -128,7 +139,7 @@ grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
}
pos++;
if (pos == (int) array->node_count)
if (pos == (int) nstripes)
pos = 0;
}
@ -139,16 +150,14 @@ grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
if (bad2 < 0)
{
/* One bad device */
if ((! grub_diskfilter_read_node (&array->nodes[p], sector,
size >> GRUB_DISK_SECTOR_BITS, buf)))
if (!read_func (data, p, sector, buf, size))
{
grub_crypto_xor (buf, buf, pbuf, size);
goto quit;
}
grub_errno = GRUB_ERR_NONE;
if (grub_diskfilter_read_node (&array->nodes[q], sector,
size >> GRUB_DISK_SECTOR_BITS, buf))
if (read_func (data, q, sector, buf, size))
goto quit;
grub_crypto_xor (buf, buf, qbuf, size);
@ -160,14 +169,12 @@ grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
/* Two bad devices */
unsigned c;
if (grub_diskfilter_read_node (&array->nodes[p], sector,
size >> GRUB_DISK_SECTOR_BITS, buf))
if (read_func (data, p, sector, buf, size))
goto quit;
grub_crypto_xor (pbuf, pbuf, buf, size);
if (grub_diskfilter_read_node (&array->nodes[q], sector,
size >> GRUB_DISK_SECTOR_BITS, buf))
if (read_func (data, q, sector, buf, size))
goto quit;
grub_crypto_xor (qbuf, qbuf, buf, size);
@ -190,6 +197,15 @@ quit:
return grub_errno;
}
static grub_err_t
grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
char *buf, grub_disk_addr_t sector, grub_size_t size)
{
return grub_raid6_recover_gen (array, array->node_count, disknr, p, buf,
sector, size << GRUB_DISK_SECTOR_BITS,
array->layout, raid6_recover_read_node);
}
GRUB_MOD_INIT(raid6rec)
{
grub_raid6_init_table ();

View file

@ -189,6 +189,15 @@ typedef grub_err_t (*grub_raid6_recover_func_t) (struct grub_diskfilter_segment
extern grub_raid5_recover_func_t grub_raid5_recover_func;
extern grub_raid6_recover_func_t grub_raid6_recover_func;
typedef grub_err_t (* raid_recover_read_t)(void *data, int disk_nr,
grub_uint64_t addr, void *dest,
grub_size_t size);
extern grub_err_t
grub_raid6_recover_gen (void *data, grub_uint64_t nstripes, int disknr, int p,
char *buf, grub_uint64_t sector, grub_size_t size,
int layout, raid_recover_read_t read_func);
grub_err_t grub_diskfilter_vg_register (struct grub_diskfilter_vg *vg);
grub_err_t