*/
set_bit(R10BIO_Uptodate, &r10_bio->state);
raid_end_bio_io(r10_bio);
+ rdev_dec_pending(conf->mirrors[dev].rdev, conf->mddev);
} else {
/*
- * oops, read error:
+ * oops, read error - keep the refcount on the rdev
*/
char b[BDEVNAME_SIZE];
if (printk_ratelimit())
bdevname(conf->mirrors[dev].rdev->bdev,b), (unsigned long long)r10_bio->sector);
reschedule_retry(r10_bio);
}
-
- rdev_dec_pending(conf->mirrors[dev].rdev, conf->mddev);
}
static void raid10_end_write_request(struct bio *bio, int error)
static int read_balance(conf_t *conf, r10bio_t *r10_bio)
{
const sector_t this_sector = r10_bio->sector;
- int disk, slot, nslot;
+ int disk, slot;
const int sectors = r10_bio->sectors;
- sector_t new_distance, current_distance;
+ sector_t new_distance, best_dist;
mdk_rdev_t *rdev;
+ int do_balance;
+ int best_slot;
raid10_find_phys(conf, r10_bio);
rcu_read_lock();
+retry:
+ best_slot = -1;
+ best_dist = MaxSector;
+ do_balance = 1;
/*
* Check if we can balance. We can balance on the whole
* device if no resync is going on (recovery is ok), or below
* above the resync window.
*/
if (conf->mddev->recovery_cp < MaxSector
- && (this_sector + sectors >= conf->next_resync)) {
- /* make sure that disk is operational */
- slot = 0;
- disk = r10_bio->devs[slot].devnum;
+ && (this_sector + sectors >= conf->next_resync))
+ do_balance = 0;
- while ((rdev = rcu_dereference(conf->mirrors[disk].rdev)) == NULL ||
- r10_bio->devs[slot].bio == IO_BLOCKED ||
- !test_bit(In_sync, &rdev->flags)) {
- slot++;
- if (slot == conf->copies) {
- slot = 0;
- disk = -1;
- break;
- }
- disk = r10_bio->devs[slot].devnum;
- }
- goto rb_out;
- }
-
-
- /* make sure the disk is operational */
- slot = 0;
- disk = r10_bio->devs[slot].devnum;
- while ((rdev=rcu_dereference(conf->mirrors[disk].rdev)) == NULL ||
- r10_bio->devs[slot].bio == IO_BLOCKED ||
- !test_bit(In_sync, &rdev->flags)) {
- slot ++;
- if (slot == conf->copies) {
- disk = -1;
- goto rb_out;
- }
+ for (slot = 0; slot < conf->copies ; slot++) {
+ if (r10_bio->devs[slot].bio == IO_BLOCKED)
+ continue;
disk = r10_bio->devs[slot].devnum;
- }
-
-
- current_distance = abs(r10_bio->devs[slot].addr -
- conf->mirrors[disk].head_position);
-
- /* Find the disk whose head is closest,
- * or - for far > 1 - find the closest to partition beginning */
-
- for (nslot = slot; nslot < conf->copies; nslot++) {
- int ndisk = r10_bio->devs[nslot].devnum;
-
-
- if ((rdev=rcu_dereference(conf->mirrors[ndisk].rdev)) == NULL ||
- r10_bio->devs[nslot].bio == IO_BLOCKED ||
- !test_bit(In_sync, &rdev->flags))
+ rdev = rcu_dereference(conf->mirrors[disk].rdev);
+ if (rdev == NULL)
+ continue;
+ if (!test_bit(In_sync, &rdev->flags))
continue;
+ if (!do_balance)
+ break;
+
/* This optimisation is debatable, and completely destroys
* sequential read speed for 'far copies' arrays. So only
* keep it for 'near' arrays, and review those later.
*/
- if (conf->near_copies > 1 && !atomic_read(&rdev->nr_pending)) {
- disk = ndisk;
- slot = nslot;
+ if (conf->near_copies > 1 && !atomic_read(&rdev->nr_pending))
break;
- }
/* for far > 1 always use the lowest address */
if (conf->far_copies > 1)
- new_distance = r10_bio->devs[nslot].addr;
+ new_distance = r10_bio->devs[slot].addr;
else
- new_distance = abs(r10_bio->devs[nslot].addr -
- conf->mirrors[ndisk].head_position);
- if (new_distance < current_distance) {
- current_distance = new_distance;
- disk = ndisk;
- slot = nslot;
+ new_distance = abs(r10_bio->devs[slot].addr -
+ conf->mirrors[disk].head_position);
+ if (new_distance < best_dist) {
+ best_dist = new_distance;
+ best_slot = slot;
}
}
+ if (slot == conf->copies)
+ slot = best_slot;
-rb_out:
- r10_bio->read_slot = slot;
-/* conf->next_seq_sect = this_sector + sectors;*/
-
- if (disk >= 0 && (rdev=rcu_dereference(conf->mirrors[disk].rdev))!= NULL)
- atomic_inc(&conf->mirrors[disk].rdev->nr_pending);
- else
+ if (slot >= 0) {
+ disk = r10_bio->devs[slot].devnum;
+ rdev = rcu_dereference(conf->mirrors[disk].rdev);
+ if (!rdev)
+ goto retry;
+ atomic_inc(&rdev->nr_pending);
+ if (test_bit(Faulty, &rdev->flags)) {
+ /* Cannot risk returning a device that failed
+ * before we inc'ed nr_pending
+ */
+ rdev_dec_pending(rdev, conf->mddev);
+ goto retry;
+ }
+ r10_bio->read_slot = slot;
+ } else
disk = -1;
rcu_read_unlock();
int max_read_errors = atomic_read(&mddev->max_corr_read_errors);
int d = r10_bio->devs[r10_bio->read_slot].devnum;
- rcu_read_lock();
- rdev = rcu_dereference(conf->mirrors[d].rdev);
- if (rdev) { /* If rdev is not NULL */
- char b[BDEVNAME_SIZE];
- int cur_read_error_count = 0;
+ /* still own a reference to this rdev, so it cannot
+ * have been cleared recently.
+ */
+ rdev = conf->mirrors[d].rdev;
- bdevname(rdev->bdev, b);
+ if (test_bit(Faulty, &rdev->flags))
+ /* drive has already been failed, just ignore any
+ more fix_read_error() attempts */
+ return;
- if (test_bit(Faulty, &rdev->flags)) {
- rcu_read_unlock();
- /* drive has already been failed, just ignore any
- more fix_read_error() attempts */
- return;
- }
+ check_decay_read_errors(mddev, rdev);
+ atomic_inc(&rdev->read_errors);
+ if (atomic_read(&rdev->read_errors) > max_read_errors) {
+ char b[BDEVNAME_SIZE];
+ bdevname(rdev->bdev, b);
- check_decay_read_errors(mddev, rdev);
- atomic_inc(&rdev->read_errors);
- cur_read_error_count = atomic_read(&rdev->read_errors);
- if (cur_read_error_count > max_read_errors) {
- rcu_read_unlock();
- printk(KERN_NOTICE
- "md/raid10:%s: %s: Raid device exceeded "
- "read_error threshold "
- "[cur %d:max %d]\n",
- mdname(mddev),
- b, cur_read_error_count, max_read_errors);
- printk(KERN_NOTICE
- "md/raid10:%s: %s: Failing raid "
- "device\n", mdname(mddev), b);
- md_error(mddev, conf->mirrors[d].rdev);
- return;
- }
+ printk(KERN_NOTICE
+ "md/raid10:%s: %s: Raid device exceeded "
+ "read_error threshold [cur %d:max %d]\n",
+ mdname(mddev), b,
+ atomic_read(&rdev->read_errors), max_read_errors);
+ printk(KERN_NOTICE
+ "md/raid10:%s: %s: Failing raid device\n",
+ mdname(mddev), b);
+ md_error(mddev, conf->mirrors[d].rdev);
+ return;
}
- rcu_read_unlock();
while(sectors) {
int s = sectors;
"write failed"
" (%d sectors at %llu on %s)\n",
mdname(mddev), s,
- (unsigned long long)(sect+
- rdev->data_offset),
+ (unsigned long long)(
+ sect + rdev->data_offset),
bdevname(rdev->bdev, b));
printk(KERN_NOTICE "md/raid10:%s: %s: failing "
"drive\n",
"corrected sectors"
" (%d sectors at %llu on %s)\n",
mdname(mddev), s,
- (unsigned long long)(sect+
- rdev->data_offset),
+ (unsigned long long)(
+ sect + rdev->data_offset),
bdevname(rdev->bdev, b));
printk(KERN_NOTICE "md/raid10:%s: %s: failing drive\n",
mdname(mddev),
"md/raid10:%s: read error corrected"
" (%d sectors at %llu on %s)\n",
mdname(mddev), s,
- (unsigned long long)(sect+
- rdev->data_offset),
+ (unsigned long long)(
+ sect + rdev->data_offset),
bdevname(rdev->bdev, b));
}
else if (test_bit(R10BIO_IsRecover, &r10_bio->state))
recovery_request_write(mddev, r10_bio);
else {
- int mirror;
+ int slot = r10_bio->read_slot;
+ int mirror = r10_bio->devs[slot].devnum;
/* we got a read error. Maybe the drive is bad. Maybe just
* the block and we can fix it.
* We freeze all other IO, and try reading the block from
fix_read_error(conf, mddev, r10_bio);
unfreeze_array(conf);
}
+ rdev_dec_pending(conf->mirrors[mirror].rdev, mddev);
bio = r10_bio->devs[r10_bio->read_slot].bio;
r10_bio->devs[r10_bio->read_slot].bio =
git.openpandora.org / pandora-kernel.git / blobdiff