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md/raid6: remove synchronous infrastructure
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These routines have been replaced by there asynchronous counterparts.

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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Yuri Tikhonov authored and Dan Williams committed Aug 30, 2009
1 parent 6c0069c commit b774ef4
Showing 1 changed file with 0 additions and 254 deletions.
254 changes: 0 additions & 254 deletions drivers/md/raid5.c
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Original file line number Diff line number Diff line change
Expand Up @@ -1927,253 +1927,6 @@ static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous)
}



/*
* Copy data between a page in the stripe cache, and one or more bion
* The page could align with the middle of the bio, or there could be
* several bion, each with several bio_vecs, which cover part of the page
* Multiple bion are linked together on bi_next. There may be extras
* at the end of this list. We ignore them.
*/
static void copy_data(int frombio, struct bio *bio,
struct page *page,
sector_t sector)
{
char *pa = page_address(page);
struct bio_vec *bvl;
int i;
int page_offset;

if (bio->bi_sector >= sector)
page_offset = (signed)(bio->bi_sector - sector) * 512;
else
page_offset = (signed)(sector - bio->bi_sector) * -512;
bio_for_each_segment(bvl, bio, i) {
int len = bio_iovec_idx(bio,i)->bv_len;
int clen;
int b_offset = 0;

if (page_offset < 0) {
b_offset = -page_offset;
page_offset += b_offset;
len -= b_offset;
}

if (len > 0 && page_offset + len > STRIPE_SIZE)
clen = STRIPE_SIZE - page_offset;
else clen = len;

if (clen > 0) {
char *ba = __bio_kmap_atomic(bio, i, KM_USER0);
if (frombio)
memcpy(pa+page_offset, ba+b_offset, clen);
else
memcpy(ba+b_offset, pa+page_offset, clen);
__bio_kunmap_atomic(ba, KM_USER0);
}
if (clen < len) /* hit end of page */
break;
page_offset += len;
}
}

#define check_xor() do { \
if (count == MAX_XOR_BLOCKS) { \
xor_blocks(count, STRIPE_SIZE, dest, ptr);\
count = 0; \
} \
} while(0)

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[syndrome_disks+2];

pd_idx = sh->pd_idx;
qd_idx = sh->qd_idx;
d0_idx = raid6_d0(sh);

pr_debug("compute_parity, stripe %llu, method %d\n",
(unsigned long long)sh->sector, method);

switch(method) {
case READ_MODIFY_WRITE:
BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */
case RECONSTRUCT_WRITE:
for (i= disks; i-- ;)
if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) {
chosen = sh->dev[i].towrite;
sh->dev[i].towrite = NULL;

if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
wake_up(&conf->wait_for_overlap);

BUG_ON(sh->dev[i].written);
sh->dev[i].written = chosen;
}
break;
case CHECK_PARITY:
BUG(); /* Not implemented yet */
}

for (i = disks; i--;)
if (sh->dev[i].written) {
sector_t sector = sh->dev[i].sector;
struct bio *wbi = sh->dev[i].written;
while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) {
copy_data(1, wbi, sh->dev[i].page, sector);
wbi = r5_next_bio(wbi, sector);
}

set_bit(R5_LOCKED, &sh->dev[i].flags);
set_bit(R5_UPTODATE, &sh->dev[i].flags);
}

/* Note that unlike RAID-5, the ordering of the disks matters greatly.*/

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, syndrome_disks);

ptrs[slot] = page_address(sh->dev[i].page);
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 != syndrome_disks);

raid6_call.gen_syndrome(syndrome_disks+2, STRIPE_SIZE, ptrs);

switch(method) {
case RECONSTRUCT_WRITE:
set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags);
set_bit(R5_LOCKED, &sh->dev[pd_idx].flags);
set_bit(R5_LOCKED, &sh->dev[qd_idx].flags);
break;
case UPDATE_PARITY:
set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags);
break;
}
}


/* Compute one missing block */
static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero)
{
int i, count, disks = sh->disks;
void *ptr[MAX_XOR_BLOCKS], *dest, *p;
int qd_idx = sh->qd_idx;

pr_debug("compute_block_1, stripe %llu, idx %d\n",
(unsigned long long)sh->sector, dd_idx);

if ( dd_idx == qd_idx ) {
/* We're actually computing the Q drive */
compute_parity6(sh, UPDATE_PARITY);
} else {
dest = page_address(sh->dev[dd_idx].page);
if (!nozero) memset(dest, 0, STRIPE_SIZE);
count = 0;
for (i = disks ; i--; ) {
if (i == dd_idx || i == qd_idx)
continue;
p = page_address(sh->dev[i].page);
if (test_bit(R5_UPTODATE, &sh->dev[i].flags))
ptr[count++] = p;
else
printk("compute_block() %d, stripe %llu, %d"
" not present\n", dd_idx,
(unsigned long long)sh->sector, i);

check_xor();
}
if (count)
xor_blocks(count, STRIPE_SIZE, dest, ptr);
if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
}
}

/* Compute two missing blocks */
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[syndrome_disks+2];

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, 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 != syndrome_disks);

BUG_ON(faila == failb);
if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; }

pr_debug("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n",
(unsigned long long)sh->sector, dd_idx1, dd_idx2,
faila, failb);

if (failb == syndrome_disks+1) {
/* Q disk is one of the missing disks */
if (faila == syndrome_disks) {
/* Missing P+Q, just recompute */
compute_parity6(sh, UPDATE_PARITY);
return;
} else {
/* We're missing D+Q; recompute D from P */
compute_block_1(sh, ((dd_idx1 == sh->qd_idx) ?
dd_idx2 : dd_idx1),
0);
compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */
return;
}
}

/* We're missing D+P or D+D; */
if (failb == syndrome_disks) {
/* We're missing D+P. */
raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE, faila, ptrs);
} else {
/* We're missing D+D. */
raid6_2data_recov(syndrome_disks+2, STRIPE_SIZE, faila, failb,
ptrs);
}

/* Both the above update both missing blocks */
set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags);
set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags);
}

static void
schedule_reconstruction(struct stripe_head *sh, struct stripe_head_state *s,
int rcw, int expand)
Expand Down Expand Up @@ -2331,13 +2084,6 @@ static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, in

static void end_reshape(raid5_conf_t *conf);

static int page_is_zero(struct page *p)
{
char *a = page_address(p);
return ((*(u32*)a) == 0 &&
memcmp(a, a+4, STRIPE_SIZE-4)==0);
}

static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous,
struct stripe_head *sh)
{
Expand Down

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