mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-22 12:14:01 +08:00
md/raid5: finish support for DDF/raid6
DDF requires RAID6 calculations over different devices in a different order. For md/raid6, we calculate over just the data devices, starting immediately after the 'Q' block. For ddf/raid6 we calculate over all devices, using zeros in place of the P and Q blocks. This requires unfortunately complex loops... Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
parent
99c0fb5f92
commit
67cc2b8165
@ -136,6 +136,10 @@ static inline void raid5_set_bi_hw_segments(struct bio *bio, unsigned int cnt)
|
||||
/* Find first data disk in a raid6 stripe */
|
||||
static inline int raid6_d0(struct stripe_head *sh)
|
||||
{
|
||||
if (sh->ddf_layout)
|
||||
/* ddf always start from first device */
|
||||
return 0;
|
||||
/* md starts just after Q block */
|
||||
if (sh->qd_idx == sh->disks - 1)
|
||||
return 0;
|
||||
else
|
||||
@ -152,13 +156,15 @@ static inline int raid6_next_disk(int disk, int raid_disks)
|
||||
* 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
|
||||
* is raid_disks-1. This help does that mapping.
|
||||
*/
|
||||
static int raid6_idx_to_slot(int idx, struct stripe_head *sh, int *count)
|
||||
static int raid6_idx_to_slot(int idx, struct stripe_head *sh,
|
||||
int *count, int syndrome_disks)
|
||||
{
|
||||
int slot;
|
||||
|
||||
if (idx == sh->pd_idx)
|
||||
return sh->disks - 2;
|
||||
return syndrome_disks;
|
||||
if (idx == sh->qd_idx)
|
||||
return sh->disks - 1;
|
||||
return syndrome_disks + 1;
|
||||
slot = (*count)++;
|
||||
return slot;
|
||||
}
|
||||
@ -1267,6 +1273,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector,
|
||||
unsigned long chunk_number;
|
||||
unsigned int chunk_offset;
|
||||
int pd_idx, qd_idx;
|
||||
int ddf_layout = 0;
|
||||
sector_t new_sector;
|
||||
int sectors_per_chunk = conf->chunk_size >> 9;
|
||||
int raid_disks = previous ? conf->previous_raid_disks
|
||||
@ -1386,6 +1393,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector,
|
||||
qd_idx = 0;
|
||||
} else if (*dd_idx >= pd_idx)
|
||||
(*dd_idx) += 2; /* D D P Q D */
|
||||
ddf_layout = 1;
|
||||
break;
|
||||
|
||||
case ALGORITHM_ROTATING_N_RESTART:
|
||||
@ -1400,6 +1408,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector,
|
||||
qd_idx = 0;
|
||||
} else if (*dd_idx >= pd_idx)
|
||||
(*dd_idx) += 2; /* D D P Q D */
|
||||
ddf_layout = 1;
|
||||
break;
|
||||
|
||||
case ALGORITHM_ROTATING_N_CONTINUE:
|
||||
@ -1407,6 +1416,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector,
|
||||
pd_idx = raid_disks - 1 - (stripe % raid_disks);
|
||||
qd_idx = (pd_idx + raid_disks - 1) % raid_disks;
|
||||
*dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
|
||||
ddf_layout = 1;
|
||||
break;
|
||||
|
||||
case ALGORITHM_LEFT_ASYMMETRIC_6:
|
||||
@ -1454,6 +1464,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector,
|
||||
if (sh) {
|
||||
sh->pd_idx = pd_idx;
|
||||
sh->qd_idx = qd_idx;
|
||||
sh->ddf_layout = ddf_layout;
|
||||
}
|
||||
/*
|
||||
* Finally, compute the new sector number
|
||||
@ -1642,9 +1653,10 @@ static void compute_parity6(struct stripe_head *sh, int method)
|
||||
{
|
||||
raid5_conf_t *conf = sh->raid_conf;
|
||||
int i, pd_idx, qd_idx, d0_idx, disks = sh->disks, count;
|
||||
int syndrome_disks = sh->ddf_layout ? disks : (disks - 2);
|
||||
struct bio *chosen;
|
||||
/**** FIX THIS: This could be very bad if disks is close to 256 ****/
|
||||
void *ptrs[disks];
|
||||
void *ptrs[syndrome_disks+2];
|
||||
|
||||
pd_idx = sh->pd_idx;
|
||||
qd_idx = sh->qd_idx;
|
||||
@ -1687,23 +1699,28 @@ static void compute_parity6(struct stripe_head *sh, int method)
|
||||
}
|
||||
|
||||
/* Note that unlike RAID-5, the ordering of the disks matters greatly.*/
|
||||
/* FIX: Is this ordering of drives even remotely optimal? */
|
||||
|
||||
for (i = 0; i < disks; i++)
|
||||
ptrs[i] = (void *)raid6_empty_zero_page;
|
||||
|
||||
count = 0;
|
||||
i = d0_idx;
|
||||
do {
|
||||
int slot = raid6_idx_to_slot(i, sh, &count);
|
||||
int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
|
||||
|
||||
ptrs[slot] = page_address(sh->dev[i].page);
|
||||
if (slot < sh->disks - 2 &&
|
||||
if (slot < syndrome_disks &&
|
||||
!test_bit(R5_UPTODATE, &sh->dev[i].flags)) {
|
||||
printk(KERN_ERR "block %d/%d not uptodate "
|
||||
"on parity calc\n", i, count);
|
||||
BUG();
|
||||
}
|
||||
|
||||
i = raid6_next_disk(i, disks);
|
||||
} while (i != d0_idx);
|
||||
BUG_ON(count+2 != disks);
|
||||
BUG_ON(count != syndrome_disks);
|
||||
|
||||
raid6_call.gen_syndrome(disks, STRIPE_SIZE, ptrs);
|
||||
raid6_call.gen_syndrome(syndrome_disks+2, STRIPE_SIZE, ptrs);
|
||||
|
||||
switch(method) {
|
||||
case RECONSTRUCT_WRITE:
|
||||
@ -1761,24 +1778,28 @@ static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero)
|
||||
static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2)
|
||||
{
|
||||
int i, count, disks = sh->disks;
|
||||
int syndrome_disks = sh->ddf_layout ? disks : disks-2;
|
||||
int d0_idx = raid6_d0(sh);
|
||||
int faila = -1, failb = -1;
|
||||
/**** FIX THIS: This could be very bad if disks is close to 256 ****/
|
||||
void *ptrs[disks];
|
||||
void *ptrs[syndrome_disks+2];
|
||||
|
||||
for (i = 0; i < disks ; i++)
|
||||
ptrs[i] = (void *)raid6_empty_zero_page;
|
||||
count = 0;
|
||||
i = d0_idx;
|
||||
do {
|
||||
int slot;
|
||||
slot = raid6_idx_to_slot(i, sh, &count);
|
||||
int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
|
||||
|
||||
ptrs[slot] = page_address(sh->dev[i].page);
|
||||
|
||||
if (i == dd_idx1)
|
||||
faila = slot;
|
||||
if (i == dd_idx2)
|
||||
failb = slot;
|
||||
i = raid6_next_disk(i, disks);
|
||||
} while (i != d0_idx);
|
||||
BUG_ON(count+2 != disks);
|
||||
BUG_ON(count != syndrome_disks);
|
||||
|
||||
BUG_ON(faila == failb);
|
||||
if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; }
|
||||
@ -1787,9 +1808,9 @@ static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2)
|
||||
(unsigned long long)sh->sector, dd_idx1, dd_idx2,
|
||||
faila, failb);
|
||||
|
||||
if ( failb == disks-1 ) {
|
||||
if (failb == syndrome_disks+1) {
|
||||
/* Q disk is one of the missing disks */
|
||||
if ( faila == disks-2 ) {
|
||||
if (faila == syndrome_disks) {
|
||||
/* Missing P+Q, just recompute */
|
||||
compute_parity6(sh, UPDATE_PARITY);
|
||||
return;
|
||||
@ -1804,12 +1825,13 @@ static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2)
|
||||
}
|
||||
|
||||
/* We're missing D+P or D+D; */
|
||||
if (failb == disks-2) {
|
||||
if (failb == syndrome_disks) {
|
||||
/* We're missing D+P. */
|
||||
raid6_datap_recov(disks, STRIPE_SIZE, faila, ptrs);
|
||||
raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE, faila, ptrs);
|
||||
} else {
|
||||
/* We're missing D+D. */
|
||||
raid6_2data_recov(disks, STRIPE_SIZE, faila, failb, ptrs);
|
||||
raid6_2data_recov(syndrome_disks+2, STRIPE_SIZE, faila, failb,
|
||||
ptrs);
|
||||
}
|
||||
|
||||
/* Both the above update both missing blocks */
|
||||
|
@ -201,6 +201,7 @@ struct stripe_head {
|
||||
sector_t sector; /* sector of this row */
|
||||
short pd_idx; /* parity disk index */
|
||||
short qd_idx; /* 'Q' disk index for raid6 */
|
||||
short ddf_layout;/* use DDF ordering to calculate Q */
|
||||
unsigned long state; /* state flags */
|
||||
atomic_t count; /* nr of active thread/requests */
|
||||
spinlock_t lock;
|
||||
|
Loading…
Reference in New Issue
Block a user