Skip to content

Commit

Permalink
[PATCH] md: factor out part of raid10d into a separate function.
Browse files Browse the repository at this point in the history 
raid10d has toooo many nested block, so take the fix_read_error functionality
out into a separate function.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
  • Loading branch information
NeilBrown authored and Linus Torvalds committed Oct 3, 2006
1 parent b5c124a commit 6814d53
Showing 1 changed file with 115 additions and 98 deletions.
213 changes: 115 additions & 98 deletions drivers/md/raid10.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1350,9 +1350,119 @@ static void recovery_request_write(mddev_t *mddev, r10bio_t *r10_bio)
*
* 1. Retries failed read operations on working mirrors.
* 2. Updates the raid superblock when problems encounter.
* 3. Performs writes following reads for array syncronising.
* 3. Performs writes following reads for array synchronising.
*/

static void fix_read_error(conf_t *conf, mddev_t *mddev, r10bio_t *r10_bio)
{
int sect = 0; /* Offset from r10_bio->sector */
int sectors = r10_bio->sectors;
mdk_rdev_t*rdev;
while(sectors) {
int s = sectors;
int sl = r10_bio->read_slot;
int success = 0;
int start;

if (s > (PAGE_SIZE>>9))
s = PAGE_SIZE >> 9;

rcu_read_lock();
do {
int d = r10_bio->devs[sl].devnum;
rdev = rcu_dereference(conf->mirrors[d].rdev);
if (rdev &&
test_bit(In_sync, &rdev->flags)) {
atomic_inc(&rdev->nr_pending);
rcu_read_unlock();
success = sync_page_io(rdev->bdev,
r10_bio->devs[sl].addr +
sect + rdev->data_offset,
s<<9,
conf->tmppage, READ);
rdev_dec_pending(rdev, mddev);
rcu_read_lock();
if (success)
break;
}
sl++;
if (sl == conf->copies)
sl = 0;
} while (!success && sl != r10_bio->read_slot);
rcu_read_unlock();

if (!success) {
/* Cannot read from anywhere -- bye bye array */
int dn = r10_bio->devs[r10_bio->read_slot].devnum;
md_error(mddev, conf->mirrors[dn].rdev);
break;
}

start = sl;
/* write it back and re-read */
rcu_read_lock();
while (sl != r10_bio->read_slot) {
int d;
if (sl==0)
sl = conf->copies;
sl--;
d = r10_bio->devs[sl].devnum;
rdev = rcu_dereference(conf->mirrors[d].rdev);
if (rdev &&
test_bit(In_sync, &rdev->flags)) {
atomic_inc(&rdev->nr_pending);
rcu_read_unlock();
atomic_add(s, &rdev->corrected_errors);
if (sync_page_io(rdev->bdev,
r10_bio->devs[sl].addr +
sect + rdev->data_offset,
s<<9, conf->tmppage, WRITE)
== 0)
/* Well, this device is dead */
md_error(mddev, rdev);
rdev_dec_pending(rdev, mddev);
rcu_read_lock();
}
}
sl = start;
while (sl != r10_bio->read_slot) {
int d;
if (sl==0)
sl = conf->copies;
sl--;
d = r10_bio->devs[sl].devnum;
rdev = rcu_dereference(conf->mirrors[d].rdev);
if (rdev &&
test_bit(In_sync, &rdev->flags)) {
char b[BDEVNAME_SIZE];
atomic_inc(&rdev->nr_pending);
rcu_read_unlock();
if (sync_page_io(rdev->bdev,
r10_bio->devs[sl].addr +
sect + rdev->data_offset,
s<<9, conf->tmppage, READ) == 0)
/* Well, this device is dead */
md_error(mddev, rdev);
else
printk(KERN_INFO
"raid10:%s: read error corrected"
" (%d sectors at %llu on %s)\n",
mdname(mddev), s,
(unsigned long long)sect+
rdev->data_offset,
bdevname(rdev->bdev, b));

rdev_dec_pending(rdev, mddev);
rcu_read_lock();
}
}
rcu_read_unlock();

sectors -= s;
sect += s;
}
}

static void raid10d(mddev_t *mddev)
{
r10bio_t *r10_bio;
Expand Down Expand Up @@ -1413,105 +1523,12 @@ static void raid10d(mddev_t *mddev)
* This is all done synchronously while the array is
* frozen.
*/
int sect = 0; /* Offset from r10_bio->sector */
int sectors = r10_bio->sectors;
freeze_array(conf);
if (mddev->ro == 0) while(sectors) {
int s = sectors;
int sl = r10_bio->read_slot;
int success = 0;

if (s > (PAGE_SIZE>>9))
s = PAGE_SIZE >> 9;

rcu_read_lock();
do {
int d = r10_bio->devs[sl].devnum;
rdev = rcu_dereference(conf->mirrors[d].rdev);
if (rdev &&
test_bit(In_sync, &rdev->flags)) {
atomic_inc(&rdev->nr_pending);
rcu_read_unlock();
success = sync_page_io(rdev->bdev,
r10_bio->devs[sl].addr +
sect + rdev->data_offset,
s<<9,
conf->tmppage, READ);
rdev_dec_pending(rdev, mddev);
rcu_read_lock();
if (success)
break;
}
sl++;
if (sl == conf->copies)
sl = 0;
} while (!success && sl != r10_bio->read_slot);
rcu_read_unlock();

if (success) {
int start = sl;
/* write it back and re-read */
rcu_read_lock();
while (sl != r10_bio->read_slot) {
int d;
if (sl==0)
sl = conf->copies;
sl--;
d = r10_bio->devs[sl].devnum;
rdev = rcu_dereference(conf->mirrors[d].rdev);
if (rdev &&
test_bit(In_sync, &rdev->flags)) {
atomic_inc(&rdev->nr_pending);
rcu_read_unlock();
atomic_add(s, &rdev->corrected_errors);
if (sync_page_io(rdev->bdev,
r10_bio->devs[sl].addr +
sect + rdev->data_offset,
s<<9, conf->tmppage, WRITE) == 0)
/* Well, this device is dead */
md_error(mddev, rdev);
rdev_dec_pending(rdev, mddev);
rcu_read_lock();
}
}
sl = start;
while (sl != r10_bio->read_slot) {
int d;
if (sl==0)
sl = conf->copies;
sl--;
d = r10_bio->devs[sl].devnum;
rdev = rcu_dereference(conf->mirrors[d].rdev);
if (rdev &&
test_bit(In_sync, &rdev->flags)) {
atomic_inc(&rdev->nr_pending);
rcu_read_unlock();
if (sync_page_io(rdev->bdev,
r10_bio->devs[sl].addr +
sect + rdev->data_offset,
s<<9, conf->tmppage, READ) == 0)
/* Well, this device is dead */
md_error(mddev, rdev);
else
printk(KERN_INFO "raid10:%s: read error corrected (%d sectors at %llu on %s)\n",
mdname(mddev), s, (unsigned long long)(sect+rdev->data_offset), bdevname(rdev->bdev, b));

rdev_dec_pending(rdev, mddev);
rcu_read_lock();
}
}
rcu_read_unlock();
} else {
/* Cannot read from anywhere -- bye bye array */
md_error(mddev, conf->mirrors[r10_bio->devs[r10_bio->read_slot].devnum].rdev);
break;
}
sectors -= s;
sect += s;
if (mddev->ro == 0) {
freeze_array(conf);
fix_read_error(conf, mddev, r10_bio);
unfreeze_array(conf);
}

unfreeze_array(conf);

bio = r10_bio->devs[r10_bio->read_slot].bio;
r10_bio->devs[r10_bio->read_slot].bio =
mddev->ro ? IO_BLOCKED : NULL;
Expand Down

0 comments on commit 6814d53

Please sign in to comment.